/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp

Bug Summary

File:	tools/clang/lib/AST/ExprConstant.cpp
Warning:	line 5215, column 32 Access to field 'Index' results in a dereference of a null pointer (loaded from field 'CurrentCall')
Annotated Source Code

Press '?' to see keyboard shortcuts
Show analyzer invocation
clang -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name ExprConstant.cpp -analyzer-store=region -analyzer-opt-analyze-nested-blocks -analyzer-eagerly-assume -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=cplusplus -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -mrelocation-model pic -pic-level 2 -mthread-model posix -relaxed-aliasing -fmath-errno -masm-verbose -mconstructor-aliases -munwind-tables -fuse-init-array -target-cpu x86-64 -dwarf-column-info -debugger-tuning=gdb -momit-leaf-frame-pointer -ffunction-sections -fdata-sections -resource-dir /usr/lib/llvm-7/lib/clang/7.0.0 -D _DEBUG -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I /build/llvm-toolchain-snapshot-7~svn326551/build-llvm/tools/clang/lib/AST -I /build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST -I /build/llvm-toolchain-snapshot-7~svn326551/tools/clang/include -I /build/llvm-toolchain-snapshot-7~svn326551/build-llvm/tools/clang/include -I /build/llvm-toolchain-snapshot-7~svn326551/build-llvm/include -I /build/llvm-toolchain-snapshot-7~svn326551/include -U NDEBUG -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/7.3.0/../../../../include/c++/7.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/7.3.0/../../../../include/x86_64-linux-gnu/c++/7.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/7.3.0/../../../../include/x86_64-linux-gnu/c++/7.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/7.3.0/../../../../include/c++/7.3.0/backward -internal-isystem /usr/include/clang/7.0.0/include/ -internal-isystem /usr/local/include -internal-isystem /usr/lib/llvm-7/lib/clang/7.0.0/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -O2 -Wno-unused-parameter -Wwrite-strings -Wno-missing-field-initializers -Wno-long-long -Wno-maybe-uninitialized -Wno-comment -std=c++11 -fdeprecated-macro -fdebug-compilation-dir /build/llvm-toolchain-snapshot-7~svn326551/build-llvm/tools/clang/lib/AST -ferror-limit 19 -fmessage-length 0 -fvisibility-inlines-hidden -fobjc-runtime=gcc -fno-common -fdiagnostics-show-option -vectorize-loops -vectorize-slp -analyzer-checker optin.performance.Padding -analyzer-output=html -analyzer-config stable-report-filename=true -o /tmp/scan-build-2018-03-02-155150-1477-1 -x c++ /build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp
1//===--- ExprConstant.cpp - Expression Constant Evaluator -----------------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file implements the Expr constant evaluator.
11//
12// Constant expression evaluation produces four main results:
13//
14//  * A success/failure flag indicating whether constant folding was successful.
15//    This is the 'bool' return value used by most of the code in this file. A
16//    'false' return value indicates that constant folding has failed, and any
17//    appropriate diagnostic has already been produced.
18//
19//  * An evaluated result, valid only if constant folding has not failed.
20//
21//  * A flag indicating if evaluation encountered (unevaluated) side-effects.
22//    These arise in cases such as (sideEffect(), 0) and (sideEffect() || 1),
23//    where it is possible to determine the evaluated result regardless.
24//
25//  * A set of notes indicating why the evaluation was not a constant expression
26//    (under the C++11 / C++1y rules only, at the moment), or, if folding failed
27//    too, why the expression could not be folded.
28//
29// If we are checking for a potential constant expression, failure to constant
30// fold a potential constant sub-expression will be indicated by a 'false'
31// return value (the expression could not be folded) and no diagnostic (the
32// expression is not necessarily non-constant).
33//
34//===----------------------------------------------------------------------===//

36#include "clang/AST/APValue.h"
37#include "clang/AST/ASTContext.h"
38#include "clang/AST/ASTDiagnostic.h"
39#include "clang/AST/ASTLambda.h"
40#include "clang/AST/CharUnits.h"
41#include "clang/AST/Expr.h"
42#include "clang/AST/RecordLayout.h"
43#include "clang/AST/StmtVisitor.h"
44#include "clang/AST/TypeLoc.h"
45#include "clang/Basic/Builtins.h"
46#include "clang/Basic/TargetInfo.h"
47#include "llvm/Support/raw_ostream.h"
48#include <cstring>
49#include <functional>

51#define DEBUG_TYPE"exprconstant" "exprconstant"

53using namespace clang;
54using llvm::APSInt;
55using llvm::APFloat;

57static bool IsGlobalLValue(APValue::LValueBase B);

59namespace {
struct LValue;
struct CallStackFrame;
struct EvalInfo;

static QualType getType(APValue::LValueBase B) {
  if (!B) return QualType();
  if (const ValueDecl *D = B.dyn_cast<const ValueDecl*>())
    // FIXME: It's unclear where we're supposed to take the type from, and
    // this actually matters for arrays of unknown bound. Using the type of
    // the most recent declaration isn't clearly correct in general. Eg:
    //
    // extern int arr[]; void f() { extern int arr[3]; };
    // constexpr int *p = &arr[1]; // valid?
    return cast<ValueDecl>(D->getMostRecentDecl())->getType();

  const Expr *Base = B.get<const Expr*>();

  // For a materialized temporary, the type of the temporary we materialized
  // may not be the type of the expression.
  if (const MaterializeTemporaryExpr *MTE =
          dyn_cast<MaterializeTemporaryExpr>(Base)) {
    SmallVector<const Expr *, 2> CommaLHSs;
    SmallVector<SubobjectAdjustment, 2> Adjustments;
    const Expr *Temp = MTE->GetTemporaryExpr();
    const Expr *Inner = Temp->skipRValueSubobjectAdjustments(CommaLHSs,
                                                             Adjustments);
    // Keep any cv-qualifiers from the reference if we generated a temporary
    // for it directly. Otherwise use the type after adjustment.
    if (!Adjustments.empty())
      return Inner->getType();
  }

  return Base->getType();
}

/// Get an LValue path entry, which is known to not be an array index, as a
/// field or base class.
static
APValue::BaseOrMemberType getAsBaseOrMember(APValue::LValuePathEntry E) {
  APValue::BaseOrMemberType Value;
  Value.setFromOpaqueValue(E.BaseOrMember);
  return Value;
}

/// Get an LValue path entry, which is known to not be an array index, as a
/// field declaration.
static const FieldDecl *getAsField(APValue::LValuePathEntry E) {
  return dyn_cast<FieldDecl>(getAsBaseOrMember(E).getPointer());
}
/// Get an LValue path entry, which is known to not be an array index, as a
/// base class declaration.
static const CXXRecordDecl *getAsBaseClass(APValue::LValuePathEntry E) {
  return dyn_cast<CXXRecordDecl>(getAsBaseOrMember(E).getPointer());
}
/// Determine whether this LValue path entry for a base class names a virtual
/// base class.
static bool isVirtualBaseClass(APValue::LValuePathEntry E) {
  return getAsBaseOrMember(E).getInt();
}

/// Given a CallExpr, try to get the alloc_size attribute. May return null.
static const AllocSizeAttr *getAllocSizeAttr(const CallExpr *CE) {
  const FunctionDecl *Callee = CE->getDirectCallee();
  return Callee ? Callee->getAttr<AllocSizeAttr>() : nullptr;
}

/// Attempts to unwrap a CallExpr (with an alloc_size attribute) from an Expr.
/// This will look through a single cast.
///
/// Returns null if we couldn't unwrap a function with alloc_size.
static const CallExpr *tryUnwrapAllocSizeCall(const Expr *E) {
  if (!E->getType()->isPointerType())
    return nullptr;

  E = E->IgnoreParens();
  // If we're doing a variable assignment from e.g. malloc(N), there will
  // probably be a cast of some kind. Ignore it.
  if (const auto *Cast = dyn_cast<CastExpr>(E))
    E = Cast->getSubExpr()->IgnoreParens();

  if (const auto *CE = dyn_cast<CallExpr>(E))
    return getAllocSizeAttr(CE) ? CE : nullptr;
  return nullptr;
}

/// Determines whether or not the given Base contains a call to a function
/// with the alloc_size attribute.
static bool isBaseAnAllocSizeCall(APValue::LValueBase Base) {
  const auto *E = Base.dyn_cast<const Expr *>();
  return E && E->getType()->isPointerType() && tryUnwrapAllocSizeCall(E);
}

/// The bound to claim that an array of unknown bound has.
/// The value in MostDerivedArraySize is undefined in this case. So, set it
/// to an arbitrary value that's likely to loudly break things if it's used.
static const uint64_t AssumedSizeForUnsizedArray =
    std::numeric_limits<uint64_t>::max() / 2;

/// Determines if an LValue with the given LValueBase will have an unsized
/// array in its designator.
/// Find the path length and type of the most-derived subobject in the given
/// path, and find the size of the containing array, if any.
static unsigned
findMostDerivedSubobject(ASTContext &Ctx, APValue::LValueBase Base,
                         ArrayRef<APValue::LValuePathEntry> Path,
                         uint64_t &ArraySize, QualType &Type, bool &IsArray,
                         bool &FirstEntryIsUnsizedArray) {
  // This only accepts LValueBases from APValues, and APValues don't support
  // arrays that lack size info.
  assert(!isBaseAnAllocSizeCall(Base) &&(static_cast <bool> (!isBaseAnAllocSizeCall(Base) &&
 "Unsized arrays shouldn't appear here") ? void (0) : __assert_fail
 ("!isBaseAnAllocSizeCall(Base) && \"Unsized arrays shouldn't appear here\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 170, __extension__ __PRETTY_FUNCTION__))
         "Unsized arrays shouldn't appear here")(static_cast <bool> (!isBaseAnAllocSizeCall(Base) &&
 "Unsized arrays shouldn't appear here") ? void (0) : __assert_fail
 ("!isBaseAnAllocSizeCall(Base) && \"Unsized arrays shouldn't appear here\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 170, __extension__ __PRETTY_FUNCTION__));
  unsigned MostDerivedLength = 0;
  Type = getType(Base);

  for (unsigned I = 0, N = Path.size(); I != N; ++I) {
    if (Type->isArrayType()) {
      const ArrayType *AT = Ctx.getAsArrayType(Type);
      Type = AT->getElementType();
      MostDerivedLength = I + 1;
      IsArray = true;

      if (auto *CAT = dyn_cast<ConstantArrayType>(AT)) {
        ArraySize = CAT->getSize().getZExtValue();
      } else {
        assert(I == 0 && "unexpected unsized array designator")(static_cast <bool> (I == 0 && "unexpected unsized array designator"
) ? void (0) : __assert_fail ("I == 0 && \"unexpected unsized array designator\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 184, __extension__ __PRETTY_FUNCTION__));
        FirstEntryIsUnsizedArray = true;
        ArraySize = AssumedSizeForUnsizedArray;
      }
    } else if (Type->isAnyComplexType()) {
      const ComplexType *CT = Type->castAs<ComplexType>();
      Type = CT->getElementType();
      ArraySize = 2;
      MostDerivedLength = I + 1;
      IsArray = true;
    } else if (const FieldDecl *FD = getAsField(Path[I])) {
      Type = FD->getType();
      ArraySize = 0;
      MostDerivedLength = I + 1;
      IsArray = false;
    } else {
      // Path[I] describes a base class.
      ArraySize = 0;
      IsArray = false;
    }
  }
  return MostDerivedLength;
}

// The order of this enum is important for diagnostics.
enum CheckSubobjectKind {
  CSK_Base, CSK_Derived, CSK_Field, CSK_ArrayToPointer, CSK_ArrayIndex,
  CSK_This, CSK_Real, CSK_Imag
};

/// A path from a glvalue to a subobject of that glvalue.
struct SubobjectDesignator {
  /// True if the subobject was named in a manner not supported by C++11. Such
  /// lvalues can still be folded, but they are not core constant expressions
  /// and we cannot perform lvalue-to-rvalue conversions on them.
  unsigned Invalid : 1;

  /// Is this a pointer one past the end of an object?
  unsigned IsOnePastTheEnd : 1;

  /// Indicator of whether the first entry is an unsized array.
  unsigned FirstEntryIsAnUnsizedArray : 1;

  /// Indicator of whether the most-derived object is an array element.
  unsigned MostDerivedIsArrayElement : 1;

  /// The length of the path to the most-derived object of which this is a
  /// subobject.
  unsigned MostDerivedPathLength : 28;

  /// The size of the array of which the most-derived object is an element.
  /// This will always be 0 if the most-derived object is not an array
  /// element. 0 is not an indicator of whether or not the most-derived object
  /// is an array, however, because 0-length arrays are allowed.
  ///
  /// If the current array is an unsized array, the value of this is
  /// undefined.
  uint64_t MostDerivedArraySize;

  /// The type of the most derived object referred to by this address.
  QualType MostDerivedType;

  typedef APValue::LValuePathEntry PathEntry;

  /// The entries on the path from the glvalue to the designated subobject.
  SmallVector<PathEntry, 8> Entries;

  SubobjectDesignator() : Invalid(true) {}

  explicit SubobjectDesignator(QualType T)
      : Invalid(false), IsOnePastTheEnd(false),
        FirstEntryIsAnUnsizedArray(false), MostDerivedIsArrayElement(false),
        MostDerivedPathLength(0), MostDerivedArraySize(0),
        MostDerivedType(T) {}

  SubobjectDesignator(ASTContext &Ctx, const APValue &V)
      : Invalid(!V.isLValue() || !V.hasLValuePath()), IsOnePastTheEnd(false),
        FirstEntryIsAnUnsizedArray(false), MostDerivedIsArrayElement(false),
        MostDerivedPathLength(0), MostDerivedArraySize(0) {
    assert(V.isLValue() && "Non-LValue used to make an LValue designator?")(static_cast <bool> (V.isLValue() && "Non-LValue used to make an LValue designator?"
) ? void (0) : __assert_fail ("V.isLValue() && \"Non-LValue used to make an LValue designator?\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 263, __extension__ __PRETTY_FUNCTION__));
    if (!Invalid) {
      IsOnePastTheEnd = V.isLValueOnePastTheEnd();
      ArrayRef<PathEntry> VEntries = V.getLValuePath();
      Entries.insert(Entries.end(), VEntries.begin(), VEntries.end());
      if (V.getLValueBase()) {
        bool IsArray = false;
        bool FirstIsUnsizedArray = false;
        MostDerivedPathLength = findMostDerivedSubobject(
            Ctx, V.getLValueBase(), V.getLValuePath(), MostDerivedArraySize,
            MostDerivedType, IsArray, FirstIsUnsizedArray);
        MostDerivedIsArrayElement = IsArray;
        FirstEntryIsAnUnsizedArray = FirstIsUnsizedArray;
      }
    }
  }

  void setInvalid() {
    Invalid = true;
    Entries.clear();
  }

  /// Determine whether the most derived subobject is an array without a
  /// known bound.
  bool isMostDerivedAnUnsizedArray() const {
    assert(!Invalid && "Calling this makes no sense on invalid designators")(static_cast <bool> (!Invalid && "Calling this makes no sense on invalid designators"
) ? void (0) : __assert_fail ("!Invalid && \"Calling this makes no sense on invalid designators\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 288, __extension__ __PRETTY_FUNCTION__));
    return Entries.size() == 1 && FirstEntryIsAnUnsizedArray;
  }

  /// Determine what the most derived array's size is. Results in an assertion
  /// failure if the most derived array lacks a size.
  uint64_t getMostDerivedArraySize() const {
    assert(!isMostDerivedAnUnsizedArray() && "Unsized array has no size")(static_cast <bool> (!isMostDerivedAnUnsizedArray() &&
 "Unsized array has no size") ? void (0) : __assert_fail ("!isMostDerivedAnUnsizedArray() && \"Unsized array has no size\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 295, __extension__ __PRETTY_FUNCTION__));
    return MostDerivedArraySize;
  }

  /// Determine whether this is a one-past-the-end pointer.
  bool isOnePastTheEnd() const {
    assert(!Invalid)(static_cast <bool> (!Invalid) ? void (0) : __assert_fail
 ("!Invalid", "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 301, __extension__ __PRETTY_FUNCTION__));
    if (IsOnePastTheEnd)
      return true;
    if (!isMostDerivedAnUnsizedArray() && MostDerivedIsArrayElement &&
        Entries[MostDerivedPathLength - 1].ArrayIndex == MostDerivedArraySize)
      return true;
    return false;
  }

  /// Check that this refers to a valid subobject.
  bool isValidSubobject() const {
    if (Invalid)
      return false;
    return !isOnePastTheEnd();
  }
  /// Check that this refers to a valid subobject, and if not, produce a
  /// relevant diagnostic and set the designator as invalid.
  bool checkSubobject(EvalInfo &Info, const Expr *E, CheckSubobjectKind CSK);

  /// Update this designator to refer to the first element within this array.
  void addArrayUnchecked(const ConstantArrayType *CAT) {
    PathEntry Entry;
    Entry.ArrayIndex = 0;
    Entries.push_back(Entry);

    // This is a most-derived object.
    MostDerivedType = CAT->getElementType();
    MostDerivedIsArrayElement = true;
    MostDerivedArraySize = CAT->getSize().getZExtValue();
    MostDerivedPathLength = Entries.size();
  }
  /// Update this designator to refer to the first element within the array of
  /// elements of type T. This is an array of unknown size.
  void addUnsizedArrayUnchecked(QualType ElemTy) {
    PathEntry Entry;
    Entry.ArrayIndex = 0;
    Entries.push_back(Entry);

    MostDerivedType = ElemTy;
    MostDerivedIsArrayElement = true;
    // The value in MostDerivedArraySize is undefined in this case. So, set it
    // to an arbitrary value that's likely to loudly break things if it's
    // used.
    MostDerivedArraySize = AssumedSizeForUnsizedArray;
    MostDerivedPathLength = Entries.size();
  }
  /// Update this designator to refer to the given base or member of this
  /// object.
  void addDeclUnchecked(const Decl *D, bool Virtual = false) {
    PathEntry Entry;
    APValue::BaseOrMemberType Value(D, Virtual);
    Entry.BaseOrMember = Value.getOpaqueValue();
    Entries.push_back(Entry);

    // If this isn't a base class, it's a new most-derived object.
    if (const FieldDecl *FD = dyn_cast<FieldDecl>(D)) {
      MostDerivedType = FD->getType();
      MostDerivedIsArrayElement = false;
      MostDerivedArraySize = 0;
      MostDerivedPathLength = Entries.size();
    }
  }
  /// Update this designator to refer to the given complex component.
  void addComplexUnchecked(QualType EltTy, bool Imag) {
    PathEntry Entry;
    Entry.ArrayIndex = Imag;
    Entries.push_back(Entry);

    // This is technically a most-derived object, though in practice this
    // is unlikely to matter.
    MostDerivedType = EltTy;
    MostDerivedIsArrayElement = true;
    MostDerivedArraySize = 2;
    MostDerivedPathLength = Entries.size();
  }
  void diagnoseUnsizedArrayPointerArithmetic(EvalInfo &Info, const Expr *E);
  void diagnosePointerArithmetic(EvalInfo &Info, const Expr *E,
                                 const APSInt &N);
  /// Add N to the address of this subobject.
  void adjustIndex(EvalInfo &Info, const Expr *E, APSInt N) {
    if (Invalid || !N) return;
    uint64_t TruncatedN = N.extOrTrunc(64).getZExtValue();
    if (isMostDerivedAnUnsizedArray()) {
      diagnoseUnsizedArrayPointerArithmetic(Info, E);
      // Can't verify -- trust that the user is doing the right thing (or if
      // not, trust that the caller will catch the bad behavior).
      // FIXME: Should we reject if this overflows, at least?
      Entries.back().ArrayIndex += TruncatedN;
      return;
    }

    // [expr.add]p4: For the purposes of these operators, a pointer to a
    // nonarray object behaves the same as a pointer to the first element of
    // an array of length one with the type of the object as its element type.
    bool IsArray = MostDerivedPathLength == Entries.size() &&
                   MostDerivedIsArrayElement;
    uint64_t ArrayIndex =
        IsArray ? Entries.back().ArrayIndex : (uint64_t)IsOnePastTheEnd;
    uint64_t ArraySize =
        IsArray ? getMostDerivedArraySize() : (uint64_t)1;

    if (N < -(int64_t)ArrayIndex || N > ArraySize - ArrayIndex) {
      // Calculate the actual index in a wide enough type, so we can include
      // it in the note.
      N = N.extend(std::max<unsigned>(N.getBitWidth() + 1, 65));
      (llvm::APInt&)N += ArrayIndex;
      assert(N.ugt(ArraySize) && "bounds check failed for in-bounds index")(static_cast <bool> (N.ugt(ArraySize) && "bounds check failed for in-bounds index"
) ? void (0) : __assert_fail ("N.ugt(ArraySize) && \"bounds check failed for in-bounds index\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 407, __extension__ __PRETTY_FUNCTION__));
      diagnosePointerArithmetic(Info, E, N);
      setInvalid();
      return;
    }

    ArrayIndex += TruncatedN;
    assert(ArrayIndex <= ArraySize &&(static_cast <bool> (ArrayIndex <= ArraySize &&
 "bounds check succeeded for out-of-bounds index") ? void (0)
 : __assert_fail ("ArrayIndex <= ArraySize && \"bounds check succeeded for out-of-bounds index\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 415, __extension__ __PRETTY_FUNCTION__))
           "bounds check succeeded for out-of-bounds index")(static_cast <bool> (ArrayIndex <= ArraySize &&
 "bounds check succeeded for out-of-bounds index") ? void (0)
 : __assert_fail ("ArrayIndex <= ArraySize && \"bounds check succeeded for out-of-bounds index\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 415, __extension__ __PRETTY_FUNCTION__));

    if (IsArray)
      Entries.back().ArrayIndex = ArrayIndex;
    else
      IsOnePastTheEnd = (ArrayIndex != 0);
  }
};

/// A stack frame in the constexpr call stack.
struct CallStackFrame {
  EvalInfo &Info;

  /// Parent - The caller of this stack frame.
  CallStackFrame *Caller;

  /// Callee - The function which was called.
  const FunctionDecl *Callee;

  /// This - The binding for the this pointer in this call, if any.
  const LValue *This;

  /// Arguments - Parameter bindings for this function call, indexed by
  /// parameters' function scope indices.
  APValue *Arguments;

  // Note that we intentionally use std::map here so that references to
  // values are stable.
  typedef std::map<const void*, APValue> MapTy;
  typedef MapTy::const_iterator temp_iterator;
  /// Temporaries - Temporary lvalues materialized within this stack frame.
  MapTy Temporaries;

  /// CallLoc - The location of the call expression for this call.
  SourceLocation CallLoc;

  /// Index - The call index of this call.
  unsigned Index;

  // FIXME: Adding this to every 'CallStackFrame' may have a nontrivial impact
  // on the overall stack usage of deeply-recursing constexpr evaluataions.
  // (We should cache this map rather than recomputing it repeatedly.)
  // But let's try this and see how it goes; we can look into caching the map
  // as a later change.

  /// LambdaCaptureFields - Mapping from captured variables/this to
  /// corresponding data members in the closure class.
  llvm::DenseMap<const VarDecl *, FieldDecl *> LambdaCaptureFields;
  FieldDecl *LambdaThisCaptureField;

  CallStackFrame(EvalInfo &Info, SourceLocation CallLoc,
                 const FunctionDecl *Callee, const LValue *This,
                 APValue *Arguments);
  ~CallStackFrame();

  APValue *getTemporary(const void *Key) {
    MapTy::iterator I = Temporaries.find(Key);
    return I == Temporaries.end() ? nullptr : &I->second;
  }
  APValue &createTemporary(const void *Key, bool IsLifetimeExtended);
};

/// Temporarily override 'this'.
class ThisOverrideRAII {
public:
  ThisOverrideRAII(CallStackFrame &Frame, const LValue *NewThis, bool Enable)
      : Frame(Frame), OldThis(Frame.This) {
    if (Enable)
      Frame.This = NewThis;
  }
  ~ThisOverrideRAII() {
    Frame.This = OldThis;
  }
private:
  CallStackFrame &Frame;
  const LValue *OldThis;
};

/// A partial diagnostic which we might know in advance that we are not going
/// to emit.
class OptionalDiagnostic {
  PartialDiagnostic *Diag;

public:
  explicit OptionalDiagnostic(PartialDiagnostic *Diag = nullptr)
    : Diag(Diag) {}

  template<typename T>
  OptionalDiagnostic &operator<<(const T &v) {
    if (Diag)
      *Diag << v;
    return *this;
  }

  OptionalDiagnostic &operator<<(const APSInt &I) {
    if (Diag) {
      SmallVector<char, 32> Buffer;
      I.toString(Buffer);
      *Diag << StringRef(Buffer.data(), Buffer.size());
    }
    return *this;
  }

  OptionalDiagnostic &operator<<(const APFloat &F) {
    if (Diag) {
      // FIXME: Force the precision of the source value down so we don't
      // print digits which are usually useless (we don't really care here if
      // we truncate a digit by accident in edge cases).  Ideally,
      // APFloat::toString would automatically print the shortest 
      // representation which rounds to the correct value, but it's a bit
      // tricky to implement.
      unsigned precision =
          llvm::APFloat::semanticsPrecision(F.getSemantics());
      precision = (precision * 59 + 195) / 196;
      SmallVector<char, 32> Buffer;
      F.toString(Buffer, precision);
      *Diag << StringRef(Buffer.data(), Buffer.size());
    }
    return *this;
  }
};

/// A cleanup, and a flag indicating whether it is lifetime-extended.
class Cleanup {
  llvm::PointerIntPair<APValue*, 1, bool> Value;

public:
  Cleanup(APValue *Val, bool IsLifetimeExtended)
      : Value(Val, IsLifetimeExtended) {}

  bool isLifetimeExtended() const { return Value.getInt(); }
  void endLifetime() {
    *Value.getPointer() = APValue();
  }
};

/// EvalInfo - This is a private struct used by the evaluator to capture
/// information about a subexpression as it is folded.  It retains information
/// about the AST context, but also maintains information about the folded
/// expression.
///
/// If an expression could be evaluated, it is still possible it is not a C
/// "integer constant expression" or constant expression.  If not, this struct
/// captures information about how and why not.
///
/// One bit of information passed *into* the request for constant folding
/// indicates whether the subexpression is "evaluated" or not according to C
/// rules.  For example, the RHS of (0 && foo()) is not evaluated.  We can
/// evaluate the expression regardless of what the RHS is, but C only allows
/// certain things in certain situations.
struct EvalInfo {
  ASTContext &Ctx;

  /// EvalStatus - Contains information about the evaluation.
  Expr::EvalStatus &EvalStatus;

  /// CurrentCall - The top of the constexpr call stack.
  CallStackFrame *CurrentCall;

  /// CallStackDepth - The number of calls in the call stack right now.
  unsigned CallStackDepth;

  /// NextCallIndex - The next call index to assign.
  unsigned NextCallIndex;

  /// StepsLeft - The remaining number of evaluation steps we're permitted
  /// to perform. This is essentially a limit for the number of statements
  /// we will evaluate.
  unsigned StepsLeft;

  /// BottomFrame - The frame in which evaluation started. This must be
  /// initialized after CurrentCall and CallStackDepth.
  CallStackFrame BottomFrame;

  /// A stack of values whose lifetimes end at the end of some surrounding
  /// evaluation frame.
  llvm::SmallVector<Cleanup, 16> CleanupStack;

  /// EvaluatingDecl - This is the declaration whose initializer is being
  /// evaluated, if any.
  APValue::LValueBase EvaluatingDecl;

  /// EvaluatingDeclValue - This is the value being constructed for the
  /// declaration whose initializer is being evaluated, if any.
  APValue *EvaluatingDeclValue;

  /// EvaluatingObject - Pair of the AST node that an lvalue represents and
  /// the call index that that lvalue was allocated in.
  typedef std::pair<APValue::LValueBase, unsigned> EvaluatingObject;

  /// EvaluatingConstructors - Set of objects that are currently being
  /// constructed.
  llvm::DenseSet<EvaluatingObject> EvaluatingConstructors;

  struct EvaluatingConstructorRAII {
    EvalInfo &EI;
    EvaluatingObject Object;
    bool DidInsert;
    EvaluatingConstructorRAII(EvalInfo &EI, EvaluatingObject Object)
        : EI(EI), Object(Object) {
      DidInsert = EI.EvaluatingConstructors.insert(Object).second;
    }
    ~EvaluatingConstructorRAII() {
      if (DidInsert) EI.EvaluatingConstructors.erase(Object);
    }
  };

  bool isEvaluatingConstructor(APValue::LValueBase Decl, unsigned CallIndex) {
    return EvaluatingConstructors.count(EvaluatingObject(Decl, CallIndex));
  }

  /// The current array initialization index, if we're performing array
  /// initialization.
  uint64_t ArrayInitIndex = -1;

  /// HasActiveDiagnostic - Was the previous diagnostic stored? If so, further
  /// notes attached to it will also be stored, otherwise they will not be.
  bool HasActiveDiagnostic;

  /// \brief Have we emitted a diagnostic explaining why we couldn't constant
  /// fold (not just why it's not strictly a constant expression)?
  bool HasFoldFailureDiagnostic;

  /// \brief Whether or not we're currently speculatively evaluating.
  bool IsSpeculativelyEvaluating;

  enum EvaluationMode {
    /// Evaluate as a constant expression. Stop if we find that the expression
    /// is not a constant expression.
    EM_ConstantExpression,

    /// Evaluate as a potential constant expression. Keep going if we hit a
    /// construct that we can't evaluate yet (because we don't yet know the
    /// value of something) but stop if we hit something that could never be
    /// a constant expression.
    EM_PotentialConstantExpression,

    /// Fold the expression to a constant. Stop if we hit a side-effect that
    /// we can't model.
    EM_ConstantFold,

    /// Evaluate the expression looking for integer overflow and similar
    /// issues. Don't worry about side-effects, and try to visit all
    /// subexpressions.
    EM_EvaluateForOverflow,

    /// Evaluate in any way we know how. Don't worry about side-effects that
    /// can't be modeled.
    EM_IgnoreSideEffects,

    /// Evaluate as a constant expression. Stop if we find that the expression
    /// is not a constant expression. Some expressions can be retried in the
    /// optimizer if we don't constant fold them here, but in an unevaluated
    /// context we try to fold them immediately since the optimizer never
    /// gets a chance to look at it.
    EM_ConstantExpressionUnevaluated,

    /// Evaluate as a potential constant expression. Keep going if we hit a
    /// construct that we can't evaluate yet (because we don't yet know the
    /// value of something) but stop if we hit something that could never be
    /// a constant expression. Some expressions can be retried in the
    /// optimizer if we don't constant fold them here, but in an unevaluated
    /// context we try to fold them immediately since the optimizer never
    /// gets a chance to look at it.
    EM_PotentialConstantExpressionUnevaluated,

    /// Evaluate as a constant expression. In certain scenarios, if:
    /// - we find a MemberExpr with a base that can't be evaluated, or
    /// - we find a variable initialized with a call to a function that has
    ///   the alloc_size attribute on it
    /// then we may consider evaluation to have succeeded.
    ///
    /// In either case, the LValue returned shall have an invalid base; in the
    /// former, the base will be the invalid MemberExpr, in the latter, the
    /// base will be either the alloc_size CallExpr or a CastExpr wrapping
    /// said CallExpr.
    EM_OffsetFold,
  } EvalMode;

  /// Are we checking whether the expression is a potential constant
  /// expression?
  bool checkingPotentialConstantExpression() const {
    return EvalMode == EM_PotentialConstantExpression ||
           EvalMode == EM_PotentialConstantExpressionUnevaluated;
  }

  /// Are we checking an expression for overflow?
  // FIXME: We should check for any kind of undefined or suspicious behavior
  // in such constructs, not just overflow.
  bool checkingForOverflow() { return EvalMode == EM_EvaluateForOverflow; }

  EvalInfo(const ASTContext &C, Expr::EvalStatus &S, EvaluationMode Mode)
    : Ctx(const_cast<ASTContext &>(C)), EvalStatus(S), CurrentCall(nullptr),
      CallStackDepth(0), NextCallIndex(1),
      StepsLeft(getLangOpts().ConstexprStepLimit),
      BottomFrame(*this, SourceLocation(), nullptr, nullptr, nullptr),
      EvaluatingDecl((const ValueDecl *)nullptr),
      EvaluatingDeclValue(nullptr), HasActiveDiagnostic(false),
      HasFoldFailureDiagnostic(false), IsSpeculativelyEvaluating(false),
      EvalMode(Mode) {}

  void setEvaluatingDecl(APValue::LValueBase Base, APValue &Value) {
    EvaluatingDecl = Base;
    EvaluatingDeclValue = &Value;
    EvaluatingConstructors.insert({Base, 0});
  }

  const LangOptions &getLangOpts() const { return Ctx.getLangOpts(); }

  bool CheckCallLimit(SourceLocation Loc) {
    // Don't perform any constexpr calls (other than the call we're checking)
    // when checking a potential constant expression.
    if (checkingPotentialConstantExpression() && CallStackDepth > 1)
      return false;
    if (NextCallIndex == 0) {
      // NextCallIndex has wrapped around.
      FFDiag(Loc, diag::note_constexpr_call_limit_exceeded);
      return false;
    }
    if (CallStackDepth <= getLangOpts().ConstexprCallDepth)
      return true;
    FFDiag(Loc, diag::note_constexpr_depth_limit_exceeded)
      << getLangOpts().ConstexprCallDepth;
    return false;
  }

  CallStackFrame *getCallFrame(unsigned CallIndex) {
    assert(CallIndex && "no call index in getCallFrame")(static_cast <bool> (CallIndex && "no call index in getCallFrame"
) ? void (0) : __assert_fail ("CallIndex && \"no call index in getCallFrame\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 742, __extension__ __PRETTY_FUNCTION__));
    // We will eventually hit BottomFrame, which has Index 1, so Frame can't
    // be null in this loop.
    CallStackFrame *Frame = CurrentCall;
    while (Frame->Index > CallIndex)
      Frame = Frame->Caller;
    return (Frame->Index == CallIndex) ? Frame : nullptr;
  }

  bool nextStep(const Stmt *S) {
    if (!StepsLeft) {
      FFDiag(S->getLocStart(), diag::note_constexpr_step_limit_exceeded);
      return false;
    }
    --StepsLeft;
    return true;
  }

private:
  /// Add a diagnostic to the diagnostics list.
  PartialDiagnostic &addDiag(SourceLocation Loc, diag::kind DiagId) {
    PartialDiagnostic PD(DiagId, Ctx.getDiagAllocator());
    EvalStatus.Diag->push_back(std::make_pair(Loc, PD));
    return EvalStatus.Diag->back().second;
  }

  /// Add notes containing a call stack to the current point of evaluation.
  void addCallStack(unsigned Limit);

private:
  OptionalDiagnostic Diag(SourceLocation Loc, diag::kind DiagId,
                          unsigned ExtraNotes, bool IsCCEDiag) {
  
    if (EvalStatus.Diag) {
      // If we have a prior diagnostic, it will be noting that the expression
      // isn't a constant expression. This diagnostic is more important,
      // unless we require this evaluation to produce a constant expression.
      //
      // FIXME: We might want to show both diagnostics to the user in
      // EM_ConstantFold mode.
      if (!EvalStatus.Diag->empty()) {
        switch (EvalMode) {
        case EM_ConstantFold:
        case EM_IgnoreSideEffects:
        case EM_EvaluateForOverflow:
          if (!HasFoldFailureDiagnostic)
            break;
          // We've already failed to fold something. Keep that diagnostic.
          LLVM_FALLTHROUGH[[clang::fallthrough]];
        case EM_ConstantExpression:
        case EM_PotentialConstantExpression:
        case EM_ConstantExpressionUnevaluated:
        case EM_PotentialConstantExpressionUnevaluated:
        case EM_OffsetFold:
          HasActiveDiagnostic = false;
          return OptionalDiagnostic();
        }
      }

      unsigned CallStackNotes = CallStackDepth - 1;
      unsigned Limit = Ctx.getDiagnostics().getConstexprBacktraceLimit();
      if (Limit)
        CallStackNotes = std::min(CallStackNotes, Limit + 1);
      if (checkingPotentialConstantExpression())
        CallStackNotes = 0;

      HasActiveDiagnostic = true;
      HasFoldFailureDiagnostic = !IsCCEDiag;
      EvalStatus.Diag->clear();
      EvalStatus.Diag->reserve(1 + ExtraNotes + CallStackNotes);
      addDiag(Loc, DiagId);
      if (!checkingPotentialConstantExpression())
        addCallStack(Limit);
      return OptionalDiagnostic(&(*EvalStatus.Diag)[0].second);
    }
    HasActiveDiagnostic = false;
    return OptionalDiagnostic();
  }
public:
  // Diagnose that the evaluation could not be folded (FF => FoldFailure)
  OptionalDiagnostic
  FFDiag(SourceLocation Loc,
        diag::kind DiagId = diag::note_invalid_subexpr_in_const_expr,
        unsigned ExtraNotes = 0) {
    return Diag(Loc, DiagId, ExtraNotes, false);
  }
  
  OptionalDiagnostic FFDiag(const Expr *E, diag::kind DiagId
                            = diag::note_invalid_subexpr_in_const_expr,
                          unsigned ExtraNotes = 0) {
    if (EvalStatus.Diag)
      return Diag(E->getExprLoc(), DiagId, ExtraNotes, /*IsCCEDiag*/false);
    HasActiveDiagnostic = false;
    return OptionalDiagnostic();
  }

  /// Diagnose that the evaluation does not produce a C++11 core constant
  /// expression.
  ///
  /// FIXME: Stop evaluating if we're in EM_ConstantExpression or
  /// EM_PotentialConstantExpression mode and we produce one of these.
  OptionalDiagnostic CCEDiag(SourceLocation Loc, diag::kind DiagId
                               = diag::note_invalid_subexpr_in_const_expr,
                             unsigned ExtraNotes = 0) {
    // Don't override a previous diagnostic. Don't bother collecting
    // diagnostics if we're evaluating for overflow.
    if (!EvalStatus.Diag || !EvalStatus.Diag->empty()) {
      HasActiveDiagnostic = false;
      return OptionalDiagnostic();
    }
    return Diag(Loc, DiagId, ExtraNotes, true);
  }
  OptionalDiagnostic CCEDiag(const Expr *E, diag::kind DiagId
                               = diag::note_invalid_subexpr_in_const_expr,
                             unsigned ExtraNotes = 0) {
    return CCEDiag(E->getExprLoc(), DiagId, ExtraNotes);
  }
  /// Add a note to a prior diagnostic.
  OptionalDiagnostic Note(SourceLocation Loc, diag::kind DiagId) {
    if (!HasActiveDiagnostic)
      return OptionalDiagnostic();
    return OptionalDiagnostic(&addDiag(Loc, DiagId));
  }

  /// Add a stack of notes to a prior diagnostic.
  void addNotes(ArrayRef<PartialDiagnosticAt> Diags) {
    if (HasActiveDiagnostic) {
      EvalStatus.Diag->insert(EvalStatus.Diag->end(),
                              Diags.begin(), Diags.end());
    }
  }

  /// Should we continue evaluation after encountering a side-effect that we
  /// couldn't model?
  bool keepEvaluatingAfterSideEffect() {
    switch (EvalMode) {
    case EM_PotentialConstantExpression:
    case EM_PotentialConstantExpressionUnevaluated:
    case EM_EvaluateForOverflow:
    case EM_IgnoreSideEffects:
      return true;

    case EM_ConstantExpression:
    case EM_ConstantExpressionUnevaluated:
    case EM_ConstantFold:
    case EM_OffsetFold:
      return false;
    }
    llvm_unreachable("Missed EvalMode case")::llvm::llvm_unreachable_internal("Missed EvalMode case", "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 890);
  }

  /// Note that we have had a side-effect, and determine whether we should
  /// keep evaluating.
  bool noteSideEffect() {
    EvalStatus.HasSideEffects = true;
    return keepEvaluatingAfterSideEffect();
  }

  /// Should we continue evaluation after encountering undefined behavior?
  bool keepEvaluatingAfterUndefinedBehavior() {
    switch (EvalMode) {
    case EM_EvaluateForOverflow:
    case EM_IgnoreSideEffects:
    case EM_ConstantFold:
    case EM_OffsetFold:
      return true;

    case EM_PotentialConstantExpression:
    case EM_PotentialConstantExpressionUnevaluated:
    case EM_ConstantExpression:
    case EM_ConstantExpressionUnevaluated:
      return false;
    }
    llvm_unreachable("Missed EvalMode case")::llvm::llvm_unreachable_internal("Missed EvalMode case", "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 915);
  }

  /// Note that we hit something that was technically undefined behavior, but
  /// that we can evaluate past it (such as signed overflow or floating-point
  /// division by zero.)
  bool noteUndefinedBehavior() {
    EvalStatus.HasUndefinedBehavior = true;
    return keepEvaluatingAfterUndefinedBehavior();
  }

  /// Should we continue evaluation as much as possible after encountering a
  /// construct which can't be reduced to a value?
  bool keepEvaluatingAfterFailure() {
    if (!StepsLeft)
      return false;

    switch (EvalMode) {
    case EM_PotentialConstantExpression:
    case EM_PotentialConstantExpressionUnevaluated:
    case EM_EvaluateForOverflow:
      return true;

    case EM_ConstantExpression:
    case EM_ConstantExpressionUnevaluated:
    case EM_ConstantFold:
    case EM_IgnoreSideEffects:
    case EM_OffsetFold:
      return false;
    }
    llvm_unreachable("Missed EvalMode case")::llvm::llvm_unreachable_internal("Missed EvalMode case", "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 945);
  }

  /// Notes that we failed to evaluate an expression that other expressions
  /// directly depend on, and determine if we should keep evaluating. This
  /// should only be called if we actually intend to keep evaluating.
  ///
  /// Call noteSideEffect() instead if we may be able to ignore the value that
  /// we failed to evaluate, e.g. if we failed to evaluate Foo() in:
  ///
  /// (Foo(), 1)      // use noteSideEffect
  /// (Foo() || true) // use noteSideEffect
  /// Foo() + 1       // use noteFailure
  LLVM_NODISCARD[[clang::warn_unused_result]] bool noteFailure() {
    // Failure when evaluating some expression often means there is some
    // subexpression whose evaluation was skipped. Therefore, (because we
    // don't track whether we skipped an expression when unwinding after an
    // evaluation failure) every evaluation failure that bubbles up from a
    // subexpression implies that a side-effect has potentially happened. We
    // skip setting the HasSideEffects flag to true until we decide to
    // continue evaluating after that point, which happens here.
    bool KeepGoing = keepEvaluatingAfterFailure();
    EvalStatus.HasSideEffects |= KeepGoing;
    return KeepGoing;
  }

  class ArrayInitLoopIndex {
    EvalInfo &Info;
    uint64_t OuterIndex;

  public:
    ArrayInitLoopIndex(EvalInfo &Info)
        : Info(Info), OuterIndex(Info.ArrayInitIndex) {
      Info.ArrayInitIndex = 0;
    }
    ~ArrayInitLoopIndex() { Info.ArrayInitIndex = OuterIndex; }

    operator uint64_t&() { return Info.ArrayInitIndex; }
  };
};

/// Object used to treat all foldable expressions as constant expressions.
struct FoldConstant {
  EvalInfo &Info;
  bool Enabled;
  bool HadNoPriorDiags;
  EvalInfo::EvaluationMode OldMode;

  explicit FoldConstant(EvalInfo &Info, bool Enabled)
    : Info(Info),
      Enabled(Enabled),
      HadNoPriorDiags(Info.EvalStatus.Diag &&
                      Info.EvalStatus.Diag->empty() &&
                      !Info.EvalStatus.HasSideEffects),
      OldMode(Info.EvalMode) {
    if (Enabled &&
        (Info.EvalMode == EvalInfo::EM_ConstantExpression ||
         Info.EvalMode == EvalInfo::EM_ConstantExpressionUnevaluated))
      Info.EvalMode = EvalInfo::EM_ConstantFold;
  }
  void keepDiagnostics() { Enabled = false; }
  ~FoldConstant() {
    if (Enabled && HadNoPriorDiags && !Info.EvalStatus.Diag->empty() &&
        !Info.EvalStatus.HasSideEffects)
      Info.EvalStatus.Diag->clear();
    Info.EvalMode = OldMode;
  }
};

/// RAII object used to treat the current evaluation as the correct pointer
/// offset fold for the current EvalMode
struct FoldOffsetRAII {
  EvalInfo &Info;
  EvalInfo::EvaluationMode OldMode;
  explicit FoldOffsetRAII(EvalInfo &Info)
      : Info(Info), OldMode(Info.EvalMode) {
    if (!Info.checkingPotentialConstantExpression())
      Info.EvalMode = EvalInfo::EM_OffsetFold;
  }

  ~FoldOffsetRAII() { Info.EvalMode = OldMode; }
};

/// RAII object used to optionally suppress diagnostics and side-effects from
/// a speculative evaluation.
class SpeculativeEvaluationRAII {
  EvalInfo *Info = nullptr;
  Expr::EvalStatus OldStatus;
  bool OldIsSpeculativelyEvaluating;

  void moveFromAndCancel(SpeculativeEvaluationRAII &&Other) {
    Info = Other.Info;
    OldStatus = Other.OldStatus;
    OldIsSpeculativelyEvaluating = Other.OldIsSpeculativelyEvaluating;
    Other.Info = nullptr;
  }

  void maybeRestoreState() {
    if (!Info)
      return;

    Info->EvalStatus = OldStatus;
    Info->IsSpeculativelyEvaluating = OldIsSpeculativelyEvaluating;
  }

public:
  SpeculativeEvaluationRAII() = default;

  SpeculativeEvaluationRAII(
      EvalInfo &Info, SmallVectorImpl<PartialDiagnosticAt> *NewDiag = nullptr)
      : Info(&Info), OldStatus(Info.EvalStatus),
        OldIsSpeculativelyEvaluating(Info.IsSpeculativelyEvaluating) {
    Info.EvalStatus.Diag = NewDiag;
    Info.IsSpeculativelyEvaluating = true;
  }

  SpeculativeEvaluationRAII(const SpeculativeEvaluationRAII &Other) = delete;
  SpeculativeEvaluationRAII(SpeculativeEvaluationRAII &&Other) {
    moveFromAndCancel(std::move(Other));
  }

  SpeculativeEvaluationRAII &operator=(SpeculativeEvaluationRAII &&Other) {
    maybeRestoreState();
    moveFromAndCancel(std::move(Other));
    return *this;
  }

  ~SpeculativeEvaluationRAII() { maybeRestoreState(); }
};

/// RAII object wrapping a full-expression or block scope, and handling
/// the ending of the lifetime of temporaries created within it.
template<bool IsFullExpression>
class ScopeRAII {
  EvalInfo &Info;
  unsigned OldStackSize;
public:
  ScopeRAII(EvalInfo &Info)
      : Info(Info), OldStackSize(Info.CleanupStack.size()) {}
  ~ScopeRAII() {
    // Body moved to a static method to encourage the compiler to inline away
    // instances of this class.
    cleanup(Info, OldStackSize);
  }
private:
  static void cleanup(EvalInfo &Info, unsigned OldStackSize) {
    unsigned NewEnd = OldStackSize;
    for (unsigned I = OldStackSize, N = Info.CleanupStack.size();
         I != N; ++I) {
      if (IsFullExpression && Info.CleanupStack[I].isLifetimeExtended()) {
        // Full-expression cleanup of a lifetime-extended temporary: nothing
        // to do, just move this cleanup to the right place in the stack.
        std::swap(Info.CleanupStack[I], Info.CleanupStack[NewEnd]);
        ++NewEnd;
      } else {
        // End the lifetime of the object.
        Info.CleanupStack[I].endLifetime();
      }
    }
    Info.CleanupStack.erase(Info.CleanupStack.begin() + NewEnd,
                            Info.CleanupStack.end());
  }
};
typedef ScopeRAII<false> BlockScopeRAII;
typedef ScopeRAII<true> FullExpressionRAII;
1110}

1112bool SubobjectDesignator::checkSubobject(EvalInfo &Info, const Expr *E,
                                       CheckSubobjectKind CSK) {
if (Invalid)
  return false;
if (isOnePastTheEnd()) {
  Info.CCEDiag(E, diag::note_constexpr_past_end_subobject)
    << CSK;
  setInvalid();
  return false;
}
// Note, we do not diagnose if isMostDerivedAnUnsizedArray(), because there
// must actually be at least one array element; even a VLA cannot have a
// bound of zero. And if our index is nonzero, we already had a CCEDiag.
return true;
1126}

1128void SubobjectDesignator::diagnoseUnsizedArrayPointerArithmetic(EvalInfo &Info,
                                                              const Expr *E) {
Info.CCEDiag(E, diag::note_constexpr_unsized_array_indexed);
// Do not set the designator as invalid: we can represent this situation,
// and correct handling of __builtin_object_size requires us to do so.
1133}

1135void SubobjectDesignator::diagnosePointerArithmetic(EvalInfo &Info,
                                                  const Expr *E,
                                                  const APSInt &N) {
// If we're complaining, we must be able to statically determine the size of
// the most derived array.
if (MostDerivedPathLength == Entries.size() && MostDerivedIsArrayElement)
  Info.CCEDiag(E, diag::note_constexpr_array_index)
    << N << /*array*/ 0
    << static_cast<unsigned>(getMostDerivedArraySize());
else
  Info.CCEDiag(E, diag::note_constexpr_array_index)
    << N << /*non-array*/ 1;
setInvalid();
1148}

1150CallStackFrame::CallStackFrame(EvalInfo &Info, SourceLocation CallLoc,
                             const FunctionDecl *Callee, const LValue *This,
                             APValue *Arguments)
  : Info(Info), Caller(Info.CurrentCall), Callee(Callee), This(This),
    Arguments(Arguments), CallLoc(CallLoc), Index(Info.NextCallIndex++) {
Info.CurrentCall = this;
++Info.CallStackDepth;
1157}

1159CallStackFrame::~CallStackFrame() {
assert(Info.CurrentCall == this && "calls retired out of order")(static_cast <bool> (Info.CurrentCall == this &&
 "calls retired out of order") ? void (0) : __assert_fail ("Info.CurrentCall == this && \"calls retired out of order\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 1160, __extension__ __PRETTY_FUNCTION__));
--Info.CallStackDepth;
Info.CurrentCall = Caller;
1163}

1165APValue &CallStackFrame::createTemporary(const void *Key,
                                       bool IsLifetimeExtended) {
APValue &Result = Temporaries[Key];
assert(Result.isUninit() && "temporary created multiple times")(static_cast <bool> (Result.isUninit() && "temporary created multiple times"
) ? void (0) : __assert_fail ("Result.isUninit() && \"temporary created multiple times\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 1168, __extension__ __PRETTY_FUNCTION__));
Info.CleanupStack.push_back(Cleanup(&Result, IsLifetimeExtended));
return Result;
1171}

1173static void describeCall(CallStackFrame *Frame, raw_ostream &Out);

1175void EvalInfo::addCallStack(unsigned Limit) {
// Determine which calls to skip, if any.
unsigned ActiveCalls = CallStackDepth - 1;
unsigned SkipStart = ActiveCalls, SkipEnd = SkipStart;
if (Limit && Limit < ActiveCalls) {
  SkipStart = Limit / 2 + Limit % 2;
  SkipEnd = ActiveCalls - Limit / 2;
}

// Walk the call stack and add the diagnostics.
unsigned CallIdx = 0;
for (CallStackFrame *Frame = CurrentCall; Frame != &BottomFrame;
     Frame = Frame->Caller, ++CallIdx) {
  // Skip this call?
  if (CallIdx >= SkipStart && CallIdx < SkipEnd) {
    if (CallIdx == SkipStart) {
      // Note that we're skipping calls.
      addDiag(Frame->CallLoc, diag::note_constexpr_calls_suppressed)
        << unsigned(ActiveCalls - Limit);
    }
    continue;
  }

  // Use a different note for an inheriting constructor, because from the
  // user's perspective it's not really a function at all.
  if (auto *CD = dyn_cast_or_null<CXXConstructorDecl>(Frame->Callee)) {
    if (CD->isInheritingConstructor()) {
      addDiag(Frame->CallLoc, diag::note_constexpr_inherited_ctor_call_here)
        << CD->getParent();
      continue;
    }
  }

  SmallVector<char, 128> Buffer;
  llvm::raw_svector_ostream Out(Buffer);
  describeCall(Frame, Out);
  addDiag(Frame->CallLoc, diag::note_constexpr_call_here) << Out.str();
}
1213}

1215namespace {
struct ComplexValue {
private:
  bool IsInt;

public:
  APSInt IntReal, IntImag;
  APFloat FloatReal, FloatImag;

  ComplexValue() : FloatReal(APFloat::Bogus()), FloatImag(APFloat::Bogus()) {}

  void makeComplexFloat() { IsInt = false; }
  bool isComplexFloat() const { return !IsInt; }
  APFloat &getComplexFloatReal() { return FloatReal; }
  APFloat &getComplexFloatImag() { return FloatImag; }

  void makeComplexInt() { IsInt = true; }
  bool isComplexInt() const { return IsInt; }
  APSInt &getComplexIntReal() { return IntReal; }
  APSInt &getComplexIntImag() { return IntImag; }

  void moveInto(APValue &v) const {
    if (isComplexFloat())
      v = APValue(FloatReal, FloatImag);
    else
      v = APValue(IntReal, IntImag);
  }
  void setFrom(const APValue &v) {
    assert(v.isComplexFloat() || v.isComplexInt())(static_cast <bool> (v.isComplexFloat() || v.isComplexInt
()) ? void (0) : __assert_fail ("v.isComplexFloat() || v.isComplexInt()"
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 1243, __extension__ __PRETTY_FUNCTION__));
    if (v.isComplexFloat()) {
      makeComplexFloat();
      FloatReal = v.getComplexFloatReal();
      FloatImag = v.getComplexFloatImag();
    } else {
      makeComplexInt();
      IntReal = v.getComplexIntReal();
      IntImag = v.getComplexIntImag();
    }
  }
};

struct LValue {
  APValue::LValueBase Base;
  CharUnits Offset;
  unsigned InvalidBase : 1;
  unsigned CallIndex : 31;
  SubobjectDesignator Designator;
  bool IsNullPtr;

  const APValue::LValueBase getLValueBase() const { return Base; }
  CharUnits &getLValueOffset() { return Offset; }
  const CharUnits &getLValueOffset() const { return Offset; }
  unsigned getLValueCallIndex() const { return CallIndex; }
  SubobjectDesignator &getLValueDesignator() { return Designator; }
  const SubobjectDesignator &getLValueDesignator() const { return Designator;}
  bool isNullPointer() const { return IsNullPtr;}

  void moveInto(APValue &V) const {
    if (Designator.Invalid)
      V = APValue(Base, Offset, APValue::NoLValuePath(), CallIndex,
                  IsNullPtr);
    else {
      assert(!InvalidBase && "APValues can't handle invalid LValue bases")(static_cast <bool> (!InvalidBase && "APValues can't handle invalid LValue bases"
) ? void (0) : __assert_fail ("!InvalidBase && \"APValues can't handle invalid LValue bases\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 1277, __extension__ __PRETTY_FUNCTION__));
      V = APValue(Base, Offset, Designator.Entries,
                  Designator.IsOnePastTheEnd, CallIndex, IsNullPtr);
    }
  }
  void setFrom(ASTContext &Ctx, const APValue &V) {
    assert(V.isLValue() && "Setting LValue from a non-LValue?")(static_cast <bool> (V.isLValue() && "Setting LValue from a non-LValue?"
) ? void (0) : __assert_fail ("V.isLValue() && \"Setting LValue from a non-LValue?\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 1283, __extension__ __PRETTY_FUNCTION__));
    Base = V.getLValueBase();
    Offset = V.getLValueOffset();
    InvalidBase = false;
    CallIndex = V.getLValueCallIndex();
    Designator = SubobjectDesignator(Ctx, V);
    IsNullPtr = V.isNullPointer();
  }

  void set(APValue::LValueBase B, unsigned I = 0, bool BInvalid = false) {
1293#ifndef NDEBUG
    // We only allow a few types of invalid bases. Enforce that here.
    if (BInvalid) {
      const auto *E = B.get<const Expr *>();
      assert((isa<MemberExpr>(E) || tryUnwrapAllocSizeCall(E)) &&(static_cast <bool> ((isa<MemberExpr>(E) || tryUnwrapAllocSizeCall
(E)) && "Unexpected type of invalid base") ? void (0)
 : __assert_fail ("(isa<MemberExpr>(E) || tryUnwrapAllocSizeCall(E)) && \"Unexpected type of invalid base\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 1298, __extension__ __PRETTY_FUNCTION__))
             "Unexpected type of invalid base")(static_cast <bool> ((isa<MemberExpr>(E) || tryUnwrapAllocSizeCall
(E)) && "Unexpected type of invalid base") ? void (0)
 : __assert_fail ("(isa<MemberExpr>(E) || tryUnwrapAllocSizeCall(E)) && \"Unexpected type of invalid base\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 1298, __extension__ __PRETTY_FUNCTION__));
    }
1300#endif

    Base = B;
    Offset = CharUnits::fromQuantity(0);
    InvalidBase = BInvalid;
    CallIndex = I;
    Designator = SubobjectDesignator(getType(B));
    IsNullPtr = false;
  }

  void setNull(QualType PointerTy, uint64_t TargetVal) {
    Base = (Expr *)nullptr;
    Offset = CharUnits::fromQuantity(TargetVal);
    InvalidBase = false;
    CallIndex = 0;
    Designator = SubobjectDesignator(PointerTy->getPointeeType());
    IsNullPtr = true;
  }

  void setInvalid(APValue::LValueBase B, unsigned I = 0) {
    set(B, I, true);
  }

  // Check that this LValue is not based on a null pointer. If it is, produce
  // a diagnostic and mark the designator as invalid.
  bool checkNullPointer(EvalInfo &Info, const Expr *E,
                        CheckSubobjectKind CSK) {
    if (Designator.Invalid)
      return false;
    if (IsNullPtr) {
      Info.CCEDiag(E, diag::note_constexpr_null_subobject)
        << CSK;
      Designator.setInvalid();
      return false;
    }
    return true;
  }

  // Check this LValue refers to an object. If not, set the designator to be
  // invalid and emit a diagnostic.
  bool checkSubobject(EvalInfo &Info, const Expr *E, CheckSubobjectKind CSK) {
    return (CSK == CSK_ArrayToPointer || checkNullPointer(Info, E, CSK)) &&
           Designator.checkSubobject(Info, E, CSK);
  }

  void addDecl(EvalInfo &Info, const Expr *E,
               const Decl *D, bool Virtual = false) {
    if (checkSubobject(Info, E, isa<FieldDecl>(D) ? CSK_Field : CSK_Base))
      Designator.addDeclUnchecked(D, Virtual);
  }
  void addUnsizedArray(EvalInfo &Info, const Expr *E, QualType ElemTy) {
    if (!Designator.Entries.empty()) {
      Info.CCEDiag(E, diag::note_constexpr_unsupported_unsized_array);
      Designator.setInvalid();
      return;
    }
    if (checkSubobject(Info, E, CSK_ArrayToPointer)) {
      assert(getType(Base)->isPointerType() || getType(Base)->isArrayType())(static_cast <bool> (getType(Base)->isPointerType() ||
 getType(Base)->isArrayType()) ? void (0) : __assert_fail (
"getType(Base)->isPointerType() || getType(Base)->isArrayType()"
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 1357, __extension__ __PRETTY_FUNCTION__));
      Designator.FirstEntryIsAnUnsizedArray = true;
      Designator.addUnsizedArrayUnchecked(ElemTy);
    }
  }
  void addArray(EvalInfo &Info, const Expr *E, const ConstantArrayType *CAT) {
    if (checkSubobject(Info, E, CSK_ArrayToPointer))
      Designator.addArrayUnchecked(CAT);
  }
  void addComplex(EvalInfo &Info, const Expr *E, QualType EltTy, bool Imag) {
    if (checkSubobject(Info, E, Imag ? CSK_Imag : CSK_Real))
      Designator.addComplexUnchecked(EltTy, Imag);
  }
  void clearIsNullPointer() {
    IsNullPtr = false;
  }
  void adjustOffsetAndIndex(EvalInfo &Info, const Expr *E,
                            const APSInt &Index, CharUnits ElementSize) {
    // An index of 0 has no effect. (In C, adding 0 to a null pointer is UB,
    // but we're not required to diagnose it and it's valid in C++.)
    if (!Index)
      return;

    // Compute the new offset in the appropriate width, wrapping at 64 bits.
    // FIXME: When compiling for a 32-bit target, we should use 32-bit
    // offsets.
    uint64_t Offset64 = Offset.getQuantity();
    uint64_t ElemSize64 = ElementSize.getQuantity();
    uint64_t Index64 = Index.extOrTrunc(64).getZExtValue();
    Offset = CharUnits::fromQuantity(Offset64 + ElemSize64 * Index64);

    if (checkNullPointer(Info, E, CSK_ArrayIndex))
      Designator.adjustIndex(Info, E, Index);
    clearIsNullPointer();
  }
  void adjustOffset(CharUnits N) {
    Offset += N;
    if (N.getQuantity())
      clearIsNullPointer();
  }
};

struct MemberPtr {
  MemberPtr() {}
  explicit MemberPtr(const ValueDecl *Decl) :
    DeclAndIsDerivedMember(Decl, false), Path() {}

  /// The member or (direct or indirect) field referred to by this member
  /// pointer, or 0 if this is a null member pointer.
  const ValueDecl *getDecl() const {
    return DeclAndIsDerivedMember.getPointer();
  }
  /// Is this actually a member of some type derived from the relevant class?
  bool isDerivedMember() const {
    return DeclAndIsDerivedMember.getInt();
  }
  /// Get the class which the declaration actually lives in.
  const CXXRecordDecl *getContainingRecord() const {
    return cast<CXXRecordDecl>(
        DeclAndIsDerivedMember.getPointer()->getDeclContext());
  }

  void moveInto(APValue &V) const {
    V = APValue(getDecl(), isDerivedMember(), Path);
  }
  void setFrom(const APValue &V) {
    assert(V.isMemberPointer())(static_cast <bool> (V.isMemberPointer()) ? void (0) : __assert_fail
 ("V.isMemberPointer()", "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 1423, __extension__ __PRETTY_FUNCTION__));
    DeclAndIsDerivedMember.setPointer(V.getMemberPointerDecl());
    DeclAndIsDerivedMember.setInt(V.isMemberPointerToDerivedMember());
    Path.clear();
    ArrayRef<const CXXRecordDecl*> P = V.getMemberPointerPath();
    Path.insert(Path.end(), P.begin(), P.end());
  }

  /// DeclAndIsDerivedMember - The member declaration, and a flag indicating
  /// whether the member is a member of some class derived from the class type
  /// of the member pointer.
  llvm::PointerIntPair<const ValueDecl*, 1, bool> DeclAndIsDerivedMember;
  /// Path - The path of base/derived classes from the member declaration's
  /// class (exclusive) to the class type of the member pointer (inclusive).
  SmallVector<const CXXRecordDecl*, 4> Path;

  /// Perform a cast towards the class of the Decl (either up or down the
  /// hierarchy).
  bool castBack(const CXXRecordDecl *Class) {
    assert(!Path.empty())(static_cast <bool> (!Path.empty()) ? void (0) : __assert_fail
 ("!Path.empty()", "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 1442, __extension__ __PRETTY_FUNCTION__));
    const CXXRecordDecl *Expected;
    if (Path.size() >= 2)
      Expected = Path[Path.size() - 2];
    else
      Expected = getContainingRecord();
    if (Expected->getCanonicalDecl() != Class->getCanonicalDecl()) {
      // C++11 [expr.static.cast]p12: In a conversion from (D::*) to (B::*),
      // if B does not contain the original member and is not a base or
      // derived class of the class containing the original member, the result
      // of the cast is undefined.
      // C++11 [conv.mem]p2 does not cover this case for a cast from (B::*) to
      // (D::*). We consider that to be a language defect.
      return false;
    }
    Path.pop_back();
    return true;
  }
  /// Perform a base-to-derived member pointer cast.
  bool castToDerived(const CXXRecordDecl *Derived) {
    if (!getDecl())
      return true;
    if (!isDerivedMember()) {
      Path.push_back(Derived);
      return true;
    }
    if (!castBack(Derived))
      return false;
    if (Path.empty())
      DeclAndIsDerivedMember.setInt(false);
    return true;
  }
  /// Perform a derived-to-base member pointer cast.
  bool castToBase(const CXXRecordDecl *Base) {
    if (!getDecl())
      return true;
    if (Path.empty())
      DeclAndIsDerivedMember.setInt(true);
    if (isDerivedMember()) {
      Path.push_back(Base);
      return true;
    }
    return castBack(Base);
  }
};

/// Compare two member pointers, which are assumed to be of the same type.
static bool operator==(const MemberPtr &LHS, const MemberPtr &RHS) {
  if (!LHS.getDecl() || !RHS.getDecl())
    return !LHS.getDecl() && !RHS.getDecl();
  if (LHS.getDecl()->getCanonicalDecl() != RHS.getDecl()->getCanonicalDecl())
    return false;
  return LHS.Path == RHS.Path;
}
1496}

1498static bool Evaluate(APValue &Result, EvalInfo &Info, const Expr *E);
1499static bool EvaluateInPlace(APValue &Result, EvalInfo &Info,
                          const LValue &This, const Expr *E,
                          bool AllowNonLiteralTypes = false);
1502static bool EvaluateLValue(const Expr *E, LValue &Result, EvalInfo &Info,
                         bool InvalidBaseOK = false);
1504static bool EvaluatePointer(const Expr *E, LValue &Result, EvalInfo &Info,
                          bool InvalidBaseOK = false);
1506static bool EvaluateMemberPointer(const Expr *E, MemberPtr &Result,
                                EvalInfo &Info);
1508static bool EvaluateTemporary(const Expr *E, LValue &Result, EvalInfo &Info);
1509static bool EvaluateInteger(const Expr *E, APSInt &Result, EvalInfo &Info);
1510static bool EvaluateIntegerOrLValue(const Expr *E, APValue &Result,
                                  EvalInfo &Info);
1512static bool EvaluateFloat(const Expr *E, APFloat &Result, EvalInfo &Info);
1513static bool EvaluateComplex(const Expr *E, ComplexValue &Res, EvalInfo &Info);
1514static bool EvaluateAtomic(const Expr *E, const LValue *This, APValue &Result,
                         EvalInfo &Info);
1516static bool EvaluateAsRValue(EvalInfo &Info, const Expr *E, APValue &Result);

1518//===----------------------------------------------------------------------===//
1519// Misc utilities
1520//===----------------------------------------------------------------------===//

1522/// Negate an APSInt in place, converting it to a signed form if necessary, and
1523/// preserving its value (by extending by up to one bit as needed).
1524static void negateAsSigned(APSInt &Int) {
if (Int.isUnsigned() || Int.isMinSignedValue()) {
  Int = Int.extend(Int.getBitWidth() + 1);
  Int.setIsSigned(true);
}
Int = -Int;
1530}

1532/// Produce a string describing the given constexpr call.
1533static void describeCall(CallStackFrame *Frame, raw_ostream &Out) {
unsigned ArgIndex = 0;
bool IsMemberCall = isa<CXXMethodDecl>(Frame->Callee) &&
                    !isa<CXXConstructorDecl>(Frame->Callee) &&
                    cast<CXXMethodDecl>(Frame->Callee)->isInstance();

if (!IsMemberCall)
  Out << *Frame->Callee << '(';

if (Frame->This && IsMemberCall) {
  APValue Val;
  Frame->This->moveInto(Val);
  Val.printPretty(Out, Frame->Info.Ctx,
                  Frame->This->Designator.MostDerivedType);
  // FIXME: Add parens around Val if needed.
  Out << "->" << *Frame->Callee << '(';
  IsMemberCall = false;
}

for (FunctionDecl::param_const_iterator I = Frame->Callee->param_begin(),
     E = Frame->Callee->param_end(); I != E; ++I, ++ArgIndex) {
  if (ArgIndex > (unsigned)IsMemberCall)
    Out << ", ";

  const ParmVarDecl *Param = *I;
  const APValue &Arg = Frame->Arguments[ArgIndex];
  Arg.printPretty(Out, Frame->Info.Ctx, Param->getType());

  if (ArgIndex == 0 && IsMemberCall)
    Out << "->" << *Frame->Callee << '(';
}

Out << ')';
1566}

1568/// Evaluate an expression to see if it had side-effects, and discard its
1569/// result.
1570/// \return \c true if the caller should keep evaluating.
1571static bool EvaluateIgnoredValue(EvalInfo &Info, const Expr *E) {
APValue Scratch;
if (!Evaluate(Scratch, Info, E))
  // We don't need the value, but we might have skipped a side effect here.
  return Info.noteSideEffect();
return true;
1577}

1579/// Should this call expression be treated as a string literal?
1580static bool IsStringLiteralCall(const CallExpr *E) {
unsigned Builtin = E->getBuiltinCallee();
return (Builtin == Builtin::BI__builtin___CFStringMakeConstantString ||
        Builtin == Builtin::BI__builtin___NSStringMakeConstantString);
1584}

1586static bool IsGlobalLValue(APValue::LValueBase B) {
// C++11 [expr.const]p3 An address constant expression is a prvalue core
// constant expression of pointer type that evaluates to...

// ... a null pointer value, or a prvalue core constant expression of type
// std::nullptr_t.
if (!B) return true;

if (const ValueDecl *D = B.dyn_cast<const ValueDecl*>()) {
  // ... the address of an object with static storage duration,
  if (const VarDecl *VD = dyn_cast<VarDecl>(D))
    return VD->hasGlobalStorage();
  // ... the address of a function,
  return isa<FunctionDecl>(D);
}

const Expr *E = B.get<const Expr*>();
switch (E->getStmtClass()) {
default:
  return false;
case Expr::CompoundLiteralExprClass: {
  const CompoundLiteralExpr *CLE = cast<CompoundLiteralExpr>(E);
  return CLE->isFileScope() && CLE->isLValue();
}
case Expr::MaterializeTemporaryExprClass:
  // A materialized temporary might have been lifetime-extended to static
  // storage duration.
  return cast<MaterializeTemporaryExpr>(E)->getStorageDuration() == SD_Static;
// A string literal has static storage duration.
case Expr::StringLiteralClass:
case Expr::PredefinedExprClass:
case Expr::ObjCStringLiteralClass:
case Expr::ObjCEncodeExprClass:
case Expr::CXXTypeidExprClass:
case Expr::CXXUuidofExprClass:
  return true;
case Expr::CallExprClass:
  return IsStringLiteralCall(cast<CallExpr>(E));
// For GCC compatibility, &&label has static storage duration.
case Expr::AddrLabelExprClass:
  return true;
// A Block literal expression may be used as the initialization value for
// Block variables at global or local static scope.
case Expr::BlockExprClass:
  return !cast<BlockExpr>(E)->getBlockDecl()->hasCaptures();
case Expr::ImplicitValueInitExprClass:
  // FIXME:
  // We can never form an lvalue with an implicit value initialization as its
  // base through expression evaluation, so these only appear in one case: the
  // implicit variable declaration we invent when checking whether a constexpr
  // constructor can produce a constant expression. We must assume that such
  // an expression might be a global lvalue.
  return true;
}
1640}

1642static void NoteLValueLocation(EvalInfo &Info, APValue::LValueBase Base) {
assert(Base && "no location for a null lvalue")(static_cast <bool> (Base && "no location for a null lvalue"
) ? void (0) : __assert_fail ("Base && \"no location for a null lvalue\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 1643, __extension__ __PRETTY_FUNCTION__));
const ValueDecl *VD = Base.dyn_cast<const ValueDecl*>();
if (VD)
  Info.Note(VD->getLocation(), diag::note_declared_at);
else
  Info.Note(Base.get<const Expr*>()->getExprLoc(),
            diag::note_constexpr_temporary_here);
1650}

1652/// Check that this reference or pointer core constant expression is a valid
1653/// value for an address or reference constant expression. Return true if we
1654/// can fold this expression, whether or not it's a constant expression.
1655static bool CheckLValueConstantExpression(EvalInfo &Info, SourceLocation Loc,
                                        QualType Type, const LValue &LVal) {
bool IsReferenceType = Type->isReferenceType();

APValue::LValueBase Base = LVal.getLValueBase();
const SubobjectDesignator &Designator = LVal.getLValueDesignator();

// Check that the object is a global. Note that the fake 'this' object we
// manufacture when checking potential constant expressions is conservatively
// assumed to be global here.
if (!IsGlobalLValue(Base)) {
  if (Info.getLangOpts().CPlusPlus11) {
    const ValueDecl *VD = Base.dyn_cast<const ValueDecl*>();
    Info.FFDiag(Loc, diag::note_constexpr_non_global, 1)
      << IsReferenceType << !Designator.Entries.empty()
      << !!VD << VD;
    NoteLValueLocation(Info, Base);
  } else {
    Info.FFDiag(Loc);
  }
  // Don't allow references to temporaries to escape.
  return false;
}
assert((Info.checkingPotentialConstantExpression() ||(static_cast <bool> ((Info.checkingPotentialConstantExpression
() || LVal.getLValueCallIndex() == 0) && "have call index for global lvalue"
) ? void (0) : __assert_fail ("(Info.checkingPotentialConstantExpression() || LVal.getLValueCallIndex() == 0) && \"have call index for global lvalue\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 1680, __extension__ __PRETTY_FUNCTION__))
        LVal.getLValueCallIndex() == 0) &&(static_cast <bool> ((Info.checkingPotentialConstantExpression
() || LVal.getLValueCallIndex() == 0) && "have call index for global lvalue"
) ? void (0) : __assert_fail ("(Info.checkingPotentialConstantExpression() || LVal.getLValueCallIndex() == 0) && \"have call index for global lvalue\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 1680, __extension__ __PRETTY_FUNCTION__))
       "have call index for global lvalue")(static_cast <bool> ((Info.checkingPotentialConstantExpression
() || LVal.getLValueCallIndex() == 0) && "have call index for global lvalue"
) ? void (0) : __assert_fail ("(Info.checkingPotentialConstantExpression() || LVal.getLValueCallIndex() == 0) && \"have call index for global lvalue\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 1680, __extension__ __PRETTY_FUNCTION__));

if (const ValueDecl *VD = Base.dyn_cast<const ValueDecl*>()) {
  if (const VarDecl *Var = dyn_cast<const VarDecl>(VD)) {
    // Check if this is a thread-local variable.
    if (Var->getTLSKind())
      return false;

    // A dllimport variable never acts like a constant.
    if (Var->hasAttr<DLLImportAttr>())
      return false;
  }
  if (const auto *FD = dyn_cast<const FunctionDecl>(VD)) {
    // __declspec(dllimport) must be handled very carefully:
    // We must never initialize an expression with the thunk in C++.
    // Doing otherwise would allow the same id-expression to yield
    // different addresses for the same function in different translation
    // units.  However, this means that we must dynamically initialize the
    // expression with the contents of the import address table at runtime.
    //
    // The C language has no notion of ODR; furthermore, it has no notion of
    // dynamic initialization.  This means that we are permitted to
    // perform initialization with the address of the thunk.
    if (Info.getLangOpts().CPlusPlus && FD->hasAttr<DLLImportAttr>())
      return false;
  }
}

// Allow address constant expressions to be past-the-end pointers. This is
// an extension: the standard requires them to point to an object.
if (!IsReferenceType)
  return true;

// A reference constant expression must refer to an object.
if (!Base) {
  // FIXME: diagnostic
  Info.CCEDiag(Loc);
  return true;
}

// Does this refer one past the end of some object?
if (!Designator.Invalid && Designator.isOnePastTheEnd()) {
  const ValueDecl *VD = Base.dyn_cast<const ValueDecl*>();
  Info.FFDiag(Loc, diag::note_constexpr_past_end, 1)
    << !Designator.Entries.empty() << !!VD << VD;
  NoteLValueLocation(Info, Base);
}

return true;
1729}

1731/// Member pointers are constant expressions unless they point to a
1732/// non-virtual dllimport member function.
1733static bool CheckMemberPointerConstantExpression(EvalInfo &Info,
                                               SourceLocation Loc,
                                               QualType Type,
                                               const APValue &Value) {
const ValueDecl *Member = Value.getMemberPointerDecl();
const auto *FD = dyn_cast_or_null<CXXMethodDecl>(Member);
if (!FD)
  return true;
return FD->isVirtual() || !FD->hasAttr<DLLImportAttr>();
1742}

1744/// Check that this core constant expression is of literal type, and if not,
1745/// produce an appropriate diagnostic.
1746static bool CheckLiteralType(EvalInfo &Info, const Expr *E,
                           const LValue *This = nullptr) {
if (!E->isRValue() || E->getType()->isLiteralType(Info.Ctx))
  return true;

// C++1y: A constant initializer for an object o [...] may also invoke
// constexpr constructors for o and its subobjects even if those objects
// are of non-literal class types.
//
// C++11 missed this detail for aggregates, so classes like this:
//   struct foo_t { union { int i; volatile int j; } u; };
// are not (obviously) initializable like so:
//   __attribute__((__require_constant_initialization__))
//   static const foo_t x = {{0}};
// because "i" is a subobject with non-literal initialization (due to the
// volatile member of the union). See:
//   http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#1677
// Therefore, we use the C++1y behavior.
if (This && Info.EvaluatingDecl == This->getLValueBase())
  return true;

// Prvalue constant expressions must be of literal types.
if (Info.getLangOpts().CPlusPlus11)
  Info.FFDiag(E, diag::note_constexpr_nonliteral)
    << E->getType();
else
  Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr);
return false;
1774}

1776/// Check that this core constant expression value is a valid value for a
1777/// constant expression. If not, report an appropriate diagnostic. Does not
1778/// check that the expression is of literal type.
1779static bool CheckConstantExpression(EvalInfo &Info, SourceLocation DiagLoc,
                                  QualType Type, const APValue &Value) {
if (Value.isUninit()) {
  Info.FFDiag(DiagLoc, diag::note_constexpr_uninitialized)
    << true << Type;
  return false;
}

// We allow _Atomic(T) to be initialized from anything that T can be
// initialized from.
if (const AtomicType *AT = Type->getAs<AtomicType>())
  Type = AT->getValueType();

// Core issue 1454: For a literal constant expression of array or class type,
// each subobject of its value shall have been initialized by a constant
// expression.
if (Value.isArray()) {
  QualType EltTy = Type->castAsArrayTypeUnsafe()->getElementType();
  for (unsigned I = 0, N = Value.getArrayInitializedElts(); I != N; ++I) {
    if (!CheckConstantExpression(Info, DiagLoc, EltTy,
                                 Value.getArrayInitializedElt(I)))
      return false;
  }
  if (!Value.hasArrayFiller())
    return true;
  return CheckConstantExpression(Info, DiagLoc, EltTy,
                                 Value.getArrayFiller());
}
if (Value.isUnion() && Value.getUnionField()) {
  return CheckConstantExpression(Info, DiagLoc,
                                 Value.getUnionField()->getType(),
                                 Value.getUnionValue());
}
if (Value.isStruct()) {
  RecordDecl *RD = Type->castAs<RecordType>()->getDecl();
  if (const CXXRecordDecl *CD = dyn_cast<CXXRecordDecl>(RD)) {
    unsigned BaseIndex = 0;
    for (CXXRecordDecl::base_class_const_iterator I = CD->bases_begin(),
           End = CD->bases_end(); I != End; ++I, ++BaseIndex) {
      if (!CheckConstantExpression(Info, DiagLoc, I->getType(),
                                   Value.getStructBase(BaseIndex)))
        return false;
    }
  }
  for (const auto *I : RD->fields()) {
    if (I->isUnnamedBitfield())
      continue;

    if (!CheckConstantExpression(Info, DiagLoc, I->getType(),
                                 Value.getStructField(I->getFieldIndex())))
      return false;
  }
}

if (Value.isLValue()) {
  LValue LVal;
  LVal.setFrom(Info.Ctx, Value);
  return CheckLValueConstantExpression(Info, DiagLoc, Type, LVal);
}

if (Value.isMemberPointer())
  return CheckMemberPointerConstantExpression(Info, DiagLoc, Type, Value);

// Everything else is fine.
return true;
1844}

1846static const ValueDecl *GetLValueBaseDecl(const LValue &LVal) {
return LVal.Base.dyn_cast<const ValueDecl*>();
1848}

1850static bool IsLiteralLValue(const LValue &Value) {
if (Value.CallIndex)
  return false;
const Expr *E = Value.Base.dyn_cast<const Expr*>();
return E && !isa<MaterializeTemporaryExpr>(E);
1855}

1857static bool IsWeakLValue(const LValue &Value) {
const ValueDecl *Decl = GetLValueBaseDecl(Value);
return Decl && Decl->isWeak();
1860}

1862static bool isZeroSized(const LValue &Value) {
const ValueDecl *Decl = GetLValueBaseDecl(Value);
if (Decl && isa<VarDecl>(Decl)) {
  QualType Ty = Decl->getType();
  if (Ty->isArrayType())
    return Ty->isIncompleteType() ||
           Decl->getASTContext().getTypeSize(Ty) == 0;
}
return false;
1871}

1873static bool EvalPointerValueAsBool(const APValue &Value, bool &Result) {
// A null base expression indicates a null pointer.  These are always
// evaluatable, and they are false unless the offset is zero.
if (!Value.getLValueBase()) {
  Result = !Value.getLValueOffset().isZero();
  return true;
}

// We have a non-null base.  These are generally known to be true, but if it's
// a weak declaration it can be null at runtime.
Result = true;
const ValueDecl *Decl = Value.getLValueBase().dyn_cast<const ValueDecl*>();
return !Decl || !Decl->isWeak();
1886}

1888static bool HandleConversionToBool(const APValue &Val, bool &Result) {
switch (Val.getKind()) {
case APValue::Uninitialized:
  return false;
case APValue::Int:
  Result = Val.getInt().getBoolValue();
  return true;
case APValue::Float:
  Result = !Val.getFloat().isZero();
  return true;
case APValue::ComplexInt:
  Result = Val.getComplexIntReal().getBoolValue() ||
           Val.getComplexIntImag().getBoolValue();
  return true;
case APValue::ComplexFloat:
  Result = !Val.getComplexFloatReal().isZero() ||
           !Val.getComplexFloatImag().isZero();
  return true;
case APValue::LValue:
  return EvalPointerValueAsBool(Val, Result);
case APValue::MemberPointer:
  Result = Val.getMemberPointerDecl();
  return true;
case APValue::Vector:
case APValue::Array:
case APValue::Struct:
case APValue::Union:
case APValue::AddrLabelDiff:
  return false;
}

llvm_unreachable("unknown APValue kind")::llvm::llvm_unreachable_internal("unknown APValue kind", "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 1919);
1920}

1922static bool EvaluateAsBooleanCondition(const Expr *E, bool &Result,
                                     EvalInfo &Info) {
assert(E->isRValue() && "missing lvalue-to-rvalue conv in bool condition")(static_cast <bool> (E->isRValue() && "missing lvalue-to-rvalue conv in bool condition"
) ? void (0) : __assert_fail ("E->isRValue() && \"missing lvalue-to-rvalue conv in bool condition\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 1924, __extension__ __PRETTY_FUNCTION__));
APValue Val;
if (!Evaluate(Val, Info, E))
  return false;
return HandleConversionToBool(Val, Result);
1929}

1931template<typename T>
1932static bool HandleOverflow(EvalInfo &Info, const Expr *E,
                         const T &SrcValue, QualType DestType) {
Info.CCEDiag(E, diag::note_constexpr_overflow)
  << SrcValue << DestType;
return Info.noteUndefinedBehavior();
1937}

1939static bool HandleFloatToIntCast(EvalInfo &Info, const Expr *E,
                               QualType SrcType, const APFloat &Value,
                               QualType DestType, APSInt &Result) {
unsigned DestWidth = Info.Ctx.getIntWidth(DestType);
// Determine whether we are converting to unsigned or signed.
bool DestSigned = DestType->isSignedIntegerOrEnumerationType();

Result = APSInt(DestWidth, !DestSigned);
bool ignored;
if (Value.convertToInteger(Result, llvm::APFloat::rmTowardZero, &ignored)
    & APFloat::opInvalidOp)
  return HandleOverflow(Info, E, Value, DestType);
return true;
1952}

1954static bool HandleFloatToFloatCast(EvalInfo &Info, const Expr *E,
                                 QualType SrcType, QualType DestType,
                                 APFloat &Result) {
APFloat Value = Result;
bool ignored;
if (Result.convert(Info.Ctx.getFloatTypeSemantics(DestType),
                   APFloat::rmNearestTiesToEven, &ignored)
    & APFloat::opOverflow)
  return HandleOverflow(Info, E, Value, DestType);
return true;
1964}

1966static APSInt HandleIntToIntCast(EvalInfo &Info, const Expr *E,
                               QualType DestType, QualType SrcType,
                               const APSInt &Value) {
unsigned DestWidth = Info.Ctx.getIntWidth(DestType);
APSInt Result = Value;
// Figure out if this is a truncate, extend or noop cast.
// If the input is signed, do a sign extend, noop, or truncate.
Result = Result.extOrTrunc(DestWidth);
Result.setIsUnsigned(DestType->isUnsignedIntegerOrEnumerationType());
return Result;
1976}

1978static bool HandleIntToFloatCast(EvalInfo &Info, const Expr *E,
                               QualType SrcType, const APSInt &Value,
                               QualType DestType, APFloat &Result) {
Result = APFloat(Info.Ctx.getFloatTypeSemantics(DestType), 1);
if (Result.convertFromAPInt(Value, Value.isSigned(),
                            APFloat::rmNearestTiesToEven)
    & APFloat::opOverflow)
  return HandleOverflow(Info, E, Value, DestType);
return true;
1987}

1989static bool truncateBitfieldValue(EvalInfo &Info, const Expr *E,
                                APValue &Value, const FieldDecl *FD) {
assert(FD->isBitField() && "truncateBitfieldValue on non-bitfield")(static_cast <bool> (FD->isBitField() && "truncateBitfieldValue on non-bitfield"
) ? void (0) : __assert_fail ("FD->isBitField() && \"truncateBitfieldValue on non-bitfield\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 1991, __extension__ __PRETTY_FUNCTION__));

if (!Value.isInt()) {
  // Trying to store a pointer-cast-to-integer into a bitfield.
  // FIXME: In this case, we should provide the diagnostic for casting
  // a pointer to an integer.
  assert(Value.isLValue() && "integral value neither int nor lvalue?")(static_cast <bool> (Value.isLValue() && "integral value neither int nor lvalue?"
) ? void (0) : __assert_fail ("Value.isLValue() && \"integral value neither int nor lvalue?\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 1997, __extension__ __PRETTY_FUNCTION__));
  Info.FFDiag(E);
  return false;
}

APSInt &Int = Value.getInt();
unsigned OldBitWidth = Int.getBitWidth();
unsigned NewBitWidth = FD->getBitWidthValue(Info.Ctx);
if (NewBitWidth < OldBitWidth)
  Int = Int.trunc(NewBitWidth).extend(OldBitWidth);
return true;
2008}

2010static bool EvalAndBitcastToAPInt(EvalInfo &Info, const Expr *E,
                                llvm::APInt &Res) {
APValue SVal;
if (!Evaluate(SVal, Info, E))
  return false;
if (SVal.isInt()) {
  Res = SVal.getInt();
  return true;
}
if (SVal.isFloat()) {
  Res = SVal.getFloat().bitcastToAPInt();
  return true;
}
if (SVal.isVector()) {
  QualType VecTy = E->getType();
  unsigned VecSize = Info.Ctx.getTypeSize(VecTy);
  QualType EltTy = VecTy->castAs<VectorType>()->getElementType();
  unsigned EltSize = Info.Ctx.getTypeSize(EltTy);
  bool BigEndian = Info.Ctx.getTargetInfo().isBigEndian();
  Res = llvm::APInt::getNullValue(VecSize);
  for (unsigned i = 0; i < SVal.getVectorLength(); i++) {
    APValue &Elt = SVal.getVectorElt(i);
    llvm::APInt EltAsInt;
    if (Elt.isInt()) {
      EltAsInt = Elt.getInt();
    } else if (Elt.isFloat()) {
      EltAsInt = Elt.getFloat().bitcastToAPInt();
    } else {
      // Don't try to handle vectors of anything other than int or float
      // (not sure if it's possible to hit this case).
      Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr);
      return false;
    }
    unsigned BaseEltSize = EltAsInt.getBitWidth();
    if (BigEndian)
      Res |= EltAsInt.zextOrTrunc(VecSize).rotr(i*EltSize+BaseEltSize);
    else
      Res |= EltAsInt.zextOrTrunc(VecSize).rotl(i*EltSize);
  }
  return true;
}
// Give up if the input isn't an int, float, or vector.  For example, we
// reject "(v4i16)(intptr_t)&a".
Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr);
return false;
2055}

2057/// Perform the given integer operation, which is known to need at most BitWidth
2058/// bits, and check for overflow in the original type (if that type was not an
2059/// unsigned type).
2060template<typename Operation>
2061static bool CheckedIntArithmetic(EvalInfo &Info, const Expr *E,
                               const APSInt &LHS, const APSInt &RHS,
                               unsigned BitWidth, Operation Op,
                               APSInt &Result) {
if (LHS.isUnsigned()) {
  Result = Op(LHS, RHS);
  return true;
}

APSInt Value(Op(LHS.extend(BitWidth), RHS.extend(BitWidth)), false);
Result = Value.trunc(LHS.getBitWidth());
if (Result.extend(BitWidth) != Value) {
  if (Info.checkingForOverflow())
    Info.Ctx.getDiagnostics().Report(E->getExprLoc(),
                                     diag::warn_integer_constant_overflow)
        << Result.toString(10) << E->getType();
  else
    return HandleOverflow(Info, E, Value, E->getType());
}
return true;
2081}

2083/// Perform the given binary integer operation.
2084static bool handleIntIntBinOp(EvalInfo &Info, const Expr *E, const APSInt &LHS,
                            BinaryOperatorKind Opcode, APSInt RHS,
                            APSInt &Result) {
switch (Opcode) {
default:
  Info.FFDiag(E);
  return false;
case BO_Mul:
  return CheckedIntArithmetic(Info, E, LHS, RHS, LHS.getBitWidth() * 2,
                              std::multiplies<APSInt>(), Result);
case BO_Add:
  return CheckedIntArithmetic(Info, E, LHS, RHS, LHS.getBitWidth() + 1,
                              std::plus<APSInt>(), Result);
case BO_Sub:
  return CheckedIntArithmetic(Info, E, LHS, RHS, LHS.getBitWidth() + 1,
                              std::minus<APSInt>(), Result);
case BO_And: Result = LHS & RHS; return true;
case BO_Xor: Result = LHS ^ RHS; return true;
case BO_Or:  Result = LHS | RHS; return true;
case BO_Div:
case BO_Rem:
  if (RHS == 0) {
    Info.FFDiag(E, diag::note_expr_divide_by_zero);
    return false;
  }
  Result = (Opcode == BO_Rem ? LHS % RHS : LHS / RHS);
  // Check for overflow case: INT_MIN / -1 or INT_MIN % -1. APSInt supports
  // this operation and gives the two's complement result.
  if (RHS.isNegative() && RHS.isAllOnesValue() &&
      LHS.isSigned() && LHS.isMinSignedValue())
    return HandleOverflow(Info, E, -LHS.extend(LHS.getBitWidth() + 1),
                          E->getType());
  return true;
case BO_Shl: {
  if (Info.getLangOpts().OpenCL)
    // OpenCL 6.3j: shift values are effectively % word size of LHS.
    RHS &= APSInt(llvm::APInt(RHS.getBitWidth(),
                  static_cast<uint64_t>(LHS.getBitWidth() - 1)),
                  RHS.isUnsigned());
  else if (RHS.isSigned() && RHS.isNegative()) {
    // During constant-folding, a negative shift is an opposite shift. Such
    // a shift is not a constant expression.
    Info.CCEDiag(E, diag::note_constexpr_negative_shift) << RHS;
    RHS = -RHS;
    goto shift_right;
  }
shift_left:
  // C++11 [expr.shift]p1: Shift width must be less than the bit width of
  // the shifted type.
  unsigned SA = (unsigned) RHS.getLimitedValue(LHS.getBitWidth()-1);
  if (SA != RHS) {
    Info.CCEDiag(E, diag::note_constexpr_large_shift)
      << RHS << E->getType() << LHS.getBitWidth();
  } else if (LHS.isSigned()) {
    // C++11 [expr.shift]p2: A signed left shift must have a non-negative
    // operand, and must not overflow the corresponding unsigned type.
    if (LHS.isNegative())
      Info.CCEDiag(E, diag::note_constexpr_lshift_of_negative) << LHS;
    else if (LHS.countLeadingZeros() < SA)
      Info.CCEDiag(E, diag::note_constexpr_lshift_discards);
  }
  Result = LHS << SA;
  return true;
}
case BO_Shr: {
  if (Info.getLangOpts().OpenCL)
    // OpenCL 6.3j: shift values are effectively % word size of LHS.
    RHS &= APSInt(llvm::APInt(RHS.getBitWidth(),
                  static_cast<uint64_t>(LHS.getBitWidth() - 1)),
                  RHS.isUnsigned());
  else if (RHS.isSigned() && RHS.isNegative()) {
    // During constant-folding, a negative shift is an opposite shift. Such a
    // shift is not a constant expression.
    Info.CCEDiag(E, diag::note_constexpr_negative_shift) << RHS;
    RHS = -RHS;
    goto shift_left;
  }
shift_right:
  // C++11 [expr.shift]p1: Shift width must be less than the bit width of the
  // shifted type.
  unsigned SA = (unsigned) RHS.getLimitedValue(LHS.getBitWidth()-1);
  if (SA != RHS)
    Info.CCEDiag(E, diag::note_constexpr_large_shift)
      << RHS << E->getType() << LHS.getBitWidth();
  Result = LHS >> SA;
  return true;
}

case BO_LT: Result = LHS < RHS; return true;
case BO_GT: Result = LHS > RHS; return true;
case BO_LE: Result = LHS <= RHS; return true;
case BO_GE: Result = LHS >= RHS; return true;
case BO_EQ: Result = LHS == RHS; return true;
case BO_NE: Result = LHS != RHS; return true;
}
2179}

2181/// Perform the given binary floating-point operation, in-place, on LHS.
2182static bool handleFloatFloatBinOp(EvalInfo &Info, const Expr *E,
                                APFloat &LHS, BinaryOperatorKind Opcode,
                                const APFloat &RHS) {
switch (Opcode) {
default:
  Info.FFDiag(E);
  return false;
case BO_Mul:
  LHS.multiply(RHS, APFloat::rmNearestTiesToEven);
  break;
case BO_Add:
  LHS.add(RHS, APFloat::rmNearestTiesToEven);
  break;
case BO_Sub:
  LHS.subtract(RHS, APFloat::rmNearestTiesToEven);
  break;
case BO_Div:
  LHS.divide(RHS, APFloat::rmNearestTiesToEven);
  break;
}

if (LHS.isInfinity() || LHS.isNaN()) {
  Info.CCEDiag(E, diag::note_constexpr_float_arithmetic) << LHS.isNaN();
  return Info.noteUndefinedBehavior();
}
return true;
2208}

2210/// Cast an lvalue referring to a base subobject to a derived class, by
2211/// truncating the lvalue's path to the given length.
2212static bool CastToDerivedClass(EvalInfo &Info, const Expr *E, LValue &Result,
                             const RecordDecl *TruncatedType,
                             unsigned TruncatedElements) {
SubobjectDesignator &D = Result.Designator;

// Check we actually point to a derived class object.
if (TruncatedElements == D.Entries.size())
  return true;
assert(TruncatedElements >= D.MostDerivedPathLength &&(static_cast <bool> (TruncatedElements >= D.MostDerivedPathLength
 && "not casting to a derived class") ? void (0) : __assert_fail
 ("TruncatedElements >= D.MostDerivedPathLength && \"not casting to a derived class\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 2221, __extension__ __PRETTY_FUNCTION__))
       "not casting to a derived class")(static_cast <bool> (TruncatedElements >= D.MostDerivedPathLength
 && "not casting to a derived class") ? void (0) : __assert_fail
 ("TruncatedElements >= D.MostDerivedPathLength && \"not casting to a derived class\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 2221, __extension__ __PRETTY_FUNCTION__));
if (!Result.checkSubobject(Info, E, CSK_Derived))
  return false;

// Truncate the path to the subobject, and remove any derived-to-base offsets.
const RecordDecl *RD = TruncatedType;
for (unsigned I = TruncatedElements, N = D.Entries.size(); I != N; ++I) {
  if (RD->isInvalidDecl()) return false;
  const ASTRecordLayout &Layout = Info.Ctx.getASTRecordLayout(RD);
  const CXXRecordDecl *Base = getAsBaseClass(D.Entries[I]);
  if (isVirtualBaseClass(D.Entries[I]))
    Result.Offset -= Layout.getVBaseClassOffset(Base);
  else
    Result.Offset -= Layout.getBaseClassOffset(Base);
  RD = Base;
}
D.Entries.resize(TruncatedElements);
return true;
2239}

2241static bool HandleLValueDirectBase(EvalInfo &Info, const Expr *E, LValue &Obj,
                                 const CXXRecordDecl *Derived,
                                 const CXXRecordDecl *Base,
                                 const ASTRecordLayout *RL = nullptr) {
if (!RL) {
  if (Derived->isInvalidDecl()) return false;
  RL = &Info.Ctx.getASTRecordLayout(Derived);
}

Obj.getLValueOffset() += RL->getBaseClassOffset(Base);
Obj.addDecl(Info, E, Base, /*Virtual*/ false);
return true;
2253}

2255static bool HandleLValueBase(EvalInfo &Info, const Expr *E, LValue &Obj,
                           const CXXRecordDecl *DerivedDecl,
                           const CXXBaseSpecifier *Base) {
const CXXRecordDecl *BaseDecl = Base->getType()->getAsCXXRecordDecl();

if (!Base->isVirtual())
  return HandleLValueDirectBase(Info, E, Obj, DerivedDecl, BaseDecl);

SubobjectDesignator &D = Obj.Designator;
if (D.Invalid)
  return false;

// Extract most-derived object and corresponding type.
DerivedDecl = D.MostDerivedType->getAsCXXRecordDecl();
if (!CastToDerivedClass(Info, E, Obj, DerivedDecl, D.MostDerivedPathLength))
  return false;

// Find the virtual base class.
if (DerivedDecl->isInvalidDecl()) return false;
const ASTRecordLayout &Layout = Info.Ctx.getASTRecordLayout(DerivedDecl);
Obj.getLValueOffset() += Layout.getVBaseClassOffset(BaseDecl);
Obj.addDecl(Info, E, BaseDecl, /*Virtual*/ true);
return true;
2278}

2280static bool HandleLValueBasePath(EvalInfo &Info, const CastExpr *E,
                               QualType Type, LValue &Result) {
for (CastExpr::path_const_iterator PathI = E->path_begin(),
                                   PathE = E->path_end();
     PathI != PathE; ++PathI) {
  if (!HandleLValueBase(Info, E, Result, Type->getAsCXXRecordDecl(),
                        *PathI))
    return false;
  Type = (*PathI)->getType();
}
return true;
2291}

2293/// Update LVal to refer to the given field, which must be a member of the type
2294/// currently described by LVal.
2295static bool HandleLValueMember(EvalInfo &Info, const Expr *E, LValue &LVal,
                             const FieldDecl *FD,
                             const ASTRecordLayout *RL = nullptr) {
if (!RL) {
  if (FD->getParent()->isInvalidDecl()) return false;
  RL = &Info.Ctx.getASTRecordLayout(FD->getParent());
}

unsigned I = FD->getFieldIndex();
LVal.adjustOffset(Info.Ctx.toCharUnitsFromBits(RL->getFieldOffset(I)));
LVal.addDecl(Info, E, FD);
return true;
2307}

2309/// Update LVal to refer to the given indirect field.
2310static bool HandleLValueIndirectMember(EvalInfo &Info, const Expr *E,
                                     LValue &LVal,
                                     const IndirectFieldDecl *IFD) {
for (const auto *C : IFD->chain())
  if (!HandleLValueMember(Info, E, LVal, cast<FieldDecl>(C)))
    return false;
return true;
2317}

2319/// Get the size of the given type in char units.
2320static bool HandleSizeof(EvalInfo &Info, SourceLocation Loc,
                       QualType Type, CharUnits &Size) {
// sizeof(void), __alignof__(void), sizeof(function) = 1 as a gcc
// extension.
if (Type->isVoidType() || Type->isFunctionType()) {
  Size = CharUnits::One();
  return true;
}

if (Type->isDependentType()) {
  Info.FFDiag(Loc);
  return false;
}

if (!Type->isConstantSizeType()) {
  // sizeof(vla) is not a constantexpr: C99 6.5.3.4p2.
  // FIXME: Better diagnostic.
  Info.FFDiag(Loc);
  return false;
}

Size = Info.Ctx.getTypeSizeInChars(Type);
return true;
2343}

2345/// Update a pointer value to model pointer arithmetic.
2346/// \param Info - Information about the ongoing evaluation.
2347/// \param E - The expression being evaluated, for diagnostic purposes.
2348/// \param LVal - The pointer value to be updated.
2349/// \param EltTy - The pointee type represented by LVal.
2350/// \param Adjustment - The adjustment, in objects of type EltTy, to add.
2351static bool HandleLValueArrayAdjustment(EvalInfo &Info, const Expr *E,
                                      LValue &LVal, QualType EltTy,
                                      APSInt Adjustment) {
CharUnits SizeOfPointee;
if (!HandleSizeof(Info, E->getExprLoc(), EltTy, SizeOfPointee))
  return false;

LVal.adjustOffsetAndIndex(Info, E, Adjustment, SizeOfPointee);
return true;
2360}

2362static bool HandleLValueArrayAdjustment(EvalInfo &Info, const Expr *E,
                                      LValue &LVal, QualType EltTy,
                                      int64_t Adjustment) {
return HandleLValueArrayAdjustment(Info, E, LVal, EltTy,
                                   APSInt::get(Adjustment));
2367}

2369/// Update an lvalue to refer to a component of a complex number.
2370/// \param Info - Information about the ongoing evaluation.
2371/// \param LVal - The lvalue to be updated.
2372/// \param EltTy - The complex number's component type.
2373/// \param Imag - False for the real component, true for the imaginary.
2374static bool HandleLValueComplexElement(EvalInfo &Info, const Expr *E,
                                     LValue &LVal, QualType EltTy,
                                     bool Imag) {
if (Imag) {
  CharUnits SizeOfComponent;
  if (!HandleSizeof(Info, E->getExprLoc(), EltTy, SizeOfComponent))
    return false;
  LVal.Offset += SizeOfComponent;
}
LVal.addComplex(Info, E, EltTy, Imag);
return true;
2385}

2387static bool handleLValueToRValueConversion(EvalInfo &Info, const Expr *Conv,
                                         QualType Type, const LValue &LVal,
                                         APValue &RVal);

2391/// Try to evaluate the initializer for a variable declaration.
2392///
2393/// \param Info   Information about the ongoing evaluation.
2394/// \param E      An expression to be used when printing diagnostics.
2395/// \param VD     The variable whose initializer should be obtained.
2396/// \param Frame  The frame in which the variable was created. Must be null
2397///               if this variable is not local to the evaluation.
2398/// \param Result Filled in with a pointer to the value of the variable.
2399static bool evaluateVarDeclInit(EvalInfo &Info, const Expr *E,
                              const VarDecl *VD, CallStackFrame *Frame,
                              APValue *&Result) {

// If this is a parameter to an active constexpr function call, perform
// argument substitution.
if (const ParmVarDecl *PVD = dyn_cast<ParmVarDecl>(VD)) {
  // Assume arguments of a potential constant expression are unknown
  // constant expressions.
  if (Info.checkingPotentialConstantExpression())
    return false;
  if (!Frame || !Frame->Arguments) {
    Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr);
    return false;
  }
  Result = &Frame->Arguments[PVD->getFunctionScopeIndex()];
  return true;
}

// If this is a local variable, dig out its value.
if (Frame) {
  Result = Frame->getTemporary(VD);
  if (!Result) {
    // Assume variables referenced within a lambda's call operator that were
    // not declared within the call operator are captures and during checking
    // of a potential constant expression, assume they are unknown constant
    // expressions.
    assert(isLambdaCallOperator(Frame->Callee) &&(static_cast <bool> (isLambdaCallOperator(Frame->Callee
) && (VD->getDeclContext() != Frame->Callee || VD
->isInitCapture()) && "missing value for local variable"
) ? void (0) : __assert_fail ("isLambdaCallOperator(Frame->Callee) && (VD->getDeclContext() != Frame->Callee || VD->isInitCapture()) && \"missing value for local variable\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 2428, __extension__ __PRETTY_FUNCTION__))
           (VD->getDeclContext() != Frame->Callee || VD->isInitCapture()) &&(static_cast <bool> (isLambdaCallOperator(Frame->Callee
) && (VD->getDeclContext() != Frame->Callee || VD
->isInitCapture()) && "missing value for local variable"
) ? void (0) : __assert_fail ("isLambdaCallOperator(Frame->Callee) && (VD->getDeclContext() != Frame->Callee || VD->isInitCapture()) && \"missing value for local variable\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 2428, __extension__ __PRETTY_FUNCTION__))
           "missing value for local variable")(static_cast <bool> (isLambdaCallOperator(Frame->Callee
) && (VD->getDeclContext() != Frame->Callee || VD
->isInitCapture()) && "missing value for local variable"
) ? void (0) : __assert_fail ("isLambdaCallOperator(Frame->Callee) && (VD->getDeclContext() != Frame->Callee || VD->isInitCapture()) && \"missing value for local variable\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 2428, __extension__ __PRETTY_FUNCTION__));
    if (Info.checkingPotentialConstantExpression())
      return false;
    // FIXME: implement capture evaluation during constant expr evaluation.
    Info.FFDiag(E->getLocStart(),
         diag::note_unimplemented_constexpr_lambda_feature_ast)
        << "captures not currently allowed";
    return false;
  }
  return true;
}

// Dig out the initializer, and use the declaration which it's attached to.
const Expr *Init = VD->getAnyInitializer(VD);
if (!Init || Init->isValueDependent()) {
  // If we're checking a potential constant expression, the variable could be
  // initialized later.
  if (!Info.checkingPotentialConstantExpression())
    Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr);
  return false;
}

// If we're currently evaluating the initializer of this declaration, use that
// in-flight value.
if (Info.EvaluatingDecl.dyn_cast<const ValueDecl*>() == VD) {
  Result = Info.EvaluatingDeclValue;
  return true;
}

// Never evaluate the initializer of a weak variable. We can't be sure that
// this is the definition which will be used.
if (VD->isWeak()) {
  Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr);
  return false;
}

// Check that we can fold the initializer. In C++, we will have already done
// this in the cases where it matters for conformance.
SmallVector<PartialDiagnosticAt, 8> Notes;
if (!VD->evaluateValue(Notes)) {
  Info.FFDiag(E, diag::note_constexpr_var_init_non_constant,
            Notes.size() + 1) << VD;
  Info.Note(VD->getLocation(), diag::note_declared_at);
  Info.addNotes(Notes);
  return false;
} else if (!VD->checkInitIsICE()) {
  Info.CCEDiag(E, diag::note_constexpr_var_init_non_constant,
               Notes.size() + 1) << VD;
  Info.Note(VD->getLocation(), diag::note_declared_at);
  Info.addNotes(Notes);
}

Result = VD->getEvaluatedValue();
return true;
2482}

2484static bool IsConstNonVolatile(QualType T) {
Qualifiers Quals = T.getQualifiers();
return Quals.hasConst() && !Quals.hasVolatile();
2487}

2489/// Get the base index of the given base class within an APValue representing
2490/// the given derived class.
2491static unsigned getBaseIndex(const CXXRecordDecl *Derived,
                           const CXXRecordDecl *Base) {
Base = Base->getCanonicalDecl();
unsigned Index = 0;
for (CXXRecordDecl::base_class_const_iterator I = Derived->bases_begin(),
       E = Derived->bases_end(); I != E; ++I, ++Index) {
  if (I->getType()->getAsCXXRecordDecl()->getCanonicalDecl() == Base)
    return Index;
}

llvm_unreachable("base class missing from derived class's bases list")::llvm::llvm_unreachable_internal("base class missing from derived class's bases list"
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 2501);
2502}

2504/// Extract the value of a character from a string literal.
2505static APSInt extractStringLiteralCharacter(EvalInfo &Info, const Expr *Lit,
                                          uint64_t Index) {
// FIXME: Support MakeStringConstant
if (const auto *ObjCEnc = dyn_cast<ObjCEncodeExpr>(Lit)) {
  std::string Str;
  Info.Ctx.getObjCEncodingForType(ObjCEnc->getEncodedType(), Str);
  assert(Index <= Str.size() && "Index too large")(static_cast <bool> (Index <= Str.size() && "Index too large"
) ? void (0) : __assert_fail ("Index <= Str.size() && \"Index too large\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 2511, __extension__ __PRETTY_FUNCTION__));
  return APSInt::getUnsigned(Str.c_str()[Index]);
}

if (auto PE = dyn_cast<PredefinedExpr>(Lit))
  Lit = PE->getFunctionName();
const StringLiteral *S = cast<StringLiteral>(Lit);
const ConstantArrayType *CAT =
    Info.Ctx.getAsConstantArrayType(S->getType());
assert(CAT && "string literal isn't an array")(static_cast <bool> (CAT && "string literal isn't an array"
) ? void (0) : __assert_fail ("CAT && \"string literal isn't an array\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 2520, __extension__ __PRETTY_FUNCTION__));
QualType CharType = CAT->getElementType();
assert(CharType->isIntegerType() && "unexpected character type")(static_cast <bool> (CharType->isIntegerType() &&
 "unexpected character type") ? void (0) : __assert_fail ("CharType->isIntegerType() && \"unexpected character type\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 2522, __extension__ __PRETTY_FUNCTION__));

APSInt Value(S->getCharByteWidth() * Info.Ctx.getCharWidth(),
             CharType->isUnsignedIntegerType());
if (Index < S->getLength())
  Value = S->getCodeUnit(Index);
return Value;
2529}

2531// Expand a string literal into an array of characters.
2532static void expandStringLiteral(EvalInfo &Info, const Expr *Lit,
                              APValue &Result) {
const StringLiteral *S = cast<StringLiteral>(Lit);
const ConstantArrayType *CAT =
    Info.Ctx.getAsConstantArrayType(S->getType());
assert(CAT && "string literal isn't an array")(static_cast <bool> (CAT && "string literal isn't an array"
) ? void (0) : __assert_fail ("CAT && \"string literal isn't an array\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 2537, __extension__ __PRETTY_FUNCTION__));
QualType CharType = CAT->getElementType();
assert(CharType->isIntegerType() && "unexpected character type")(static_cast <bool> (CharType->isIntegerType() &&
 "unexpected character type") ? void (0) : __assert_fail ("CharType->isIntegerType() && \"unexpected character type\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 2539, __extension__ __PRETTY_FUNCTION__));

unsigned Elts = CAT->getSize().getZExtValue();
Result = APValue(APValue::UninitArray(),
                 std::min(S->getLength(), Elts), Elts);
APSInt Value(S->getCharByteWidth() * Info.Ctx.getCharWidth(),
             CharType->isUnsignedIntegerType());
if (Result.hasArrayFiller())
  Result.getArrayFiller() = APValue(Value);
for (unsigned I = 0, N = Result.getArrayInitializedElts(); I != N; ++I) {
  Value = S->getCodeUnit(I);
  Result.getArrayInitializedElt(I) = APValue(Value);
}
2552}

2554// Expand an array so that it has more than Index filled elements.
2555static void expandArray(APValue &Array, unsigned Index) {
unsigned Size = Array.getArraySize();
assert(Index < Size)(static_cast <bool> (Index < Size) ? void (0) : __assert_fail
 ("Index < Size", "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 2557, __extension__ __PRETTY_FUNCTION__));

// Always at least double the number of elements for which we store a value.
unsigned OldElts = Array.getArrayInitializedElts();
unsigned NewElts = std::max(Index+1, OldElts * 2);
NewElts = std::min(Size, std::max(NewElts, 8u));

// Copy the data across.
APValue NewValue(APValue::UninitArray(), NewElts, Size);
for (unsigned I = 0; I != OldElts; ++I)
  NewValue.getArrayInitializedElt(I).swap(Array.getArrayInitializedElt(I));
for (unsigned I = OldElts; I != NewElts; ++I)
  NewValue.getArrayInitializedElt(I) = Array.getArrayFiller();
if (NewValue.hasArrayFiller())
  NewValue.getArrayFiller() = Array.getArrayFiller();
Array.swap(NewValue);
2573}

2575/// Determine whether a type would actually be read by an lvalue-to-rvalue
2576/// conversion. If it's of class type, we may assume that the copy operation
2577/// is trivial. Note that this is never true for a union type with fields
2578/// (because the copy always "reads" the active member) and always true for
2579/// a non-class type.
2580static bool isReadByLvalueToRvalueConversion(QualType T) {
CXXRecordDecl *RD = T->getBaseElementTypeUnsafe()->getAsCXXRecordDecl();
if (!RD || (RD->isUnion() && !RD->field_empty()))
  return true;
if (RD->isEmpty())
  return false;

for (auto *Field : RD->fields())
  if (isReadByLvalueToRvalueConversion(Field->getType()))
    return true;

for (auto &BaseSpec : RD->bases())
  if (isReadByLvalueToRvalueConversion(BaseSpec.getType()))
    return true;

return false;
2596}

2598/// Diagnose an attempt to read from any unreadable field within the specified
2599/// type, which might be a class type.
2600static bool diagnoseUnreadableFields(EvalInfo &Info, const Expr *E,
                                   QualType T) {
CXXRecordDecl *RD = T->getBaseElementTypeUnsafe()->getAsCXXRecordDecl();
if (!RD)
  return false;

if (!RD->hasMutableFields())
  return false;

for (auto *Field : RD->fields()) {
  // If we're actually going to read this field in some way, then it can't
  // be mutable. If we're in a union, then assigning to a mutable field
  // (even an empty one) can change the active member, so that's not OK.
  // FIXME: Add core issue number for the union case.
  if (Field->isMutable() &&
      (RD->isUnion() || isReadByLvalueToRvalueConversion(Field->getType()))) {
    Info.FFDiag(E, diag::note_constexpr_ltor_mutable, 1) << Field;
    Info.Note(Field->getLocation(), diag::note_declared_at);
    return true;
  }

  if (diagnoseUnreadableFields(Info, E, Field->getType()))
    return true;
}

for (auto &BaseSpec : RD->bases())
  if (diagnoseUnreadableFields(Info, E, BaseSpec.getType()))
    return true;

// All mutable fields were empty, and thus not actually read.
return false;
2631}

2633/// Kinds of access we can perform on an object, for diagnostics.
2634enum AccessKinds {
AK_Read,
AK_Assign,
AK_Increment,
AK_Decrement
2639};

2641namespace {
2642/// A handle to a complete object (an object that is not a subobject of
2643/// another object).
2644struct CompleteObject {
/// The value of the complete object.
APValue *Value;
/// The type of the complete object.
QualType Type;
bool LifetimeStartedInEvaluation;

CompleteObject() : Value(nullptr) {}
CompleteObject(APValue *Value, QualType Type,
               bool LifetimeStartedInEvaluation)
    : Value(Value), Type(Type),
      LifetimeStartedInEvaluation(LifetimeStartedInEvaluation) {
  assert(Value && "missing value for complete object")(static_cast <bool> (Value && "missing value for complete object"
) ? void (0) : __assert_fail ("Value && \"missing value for complete object\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 2656, __extension__ __PRETTY_FUNCTION__));
}

explicit operator bool() const { return Value; }
2660};
2661} // end anonymous namespace

2663/// Find the designated sub-object of an rvalue.
2664template<typename SubobjectHandler>
2665typename SubobjectHandler::result_type
2666findSubobject(EvalInfo &Info, const Expr *E, const CompleteObject &Obj,
            const SubobjectDesignator &Sub, SubobjectHandler &handler) {
if (Sub.Invalid)
  // A diagnostic will have already been produced.
  return handler.failed();
if (Sub.isOnePastTheEnd() || Sub.isMostDerivedAnUnsizedArray()) {
  if (Info.getLangOpts().CPlusPlus11)
    Info.FFDiag(E, Sub.isOnePastTheEnd()
                       ? diag::note_constexpr_access_past_end
                       : diag::note_constexpr_access_unsized_array)
        << handler.AccessKind;
  else
    Info.FFDiag(E);
  return handler.failed();
}

APValue *O = Obj.Value;
QualType ObjType = Obj.Type;
const FieldDecl *LastField = nullptr;
const bool MayReadMutableMembers =
    Obj.LifetimeStartedInEvaluation && Info.getLangOpts().CPlusPlus14;

// Walk the designator's path to find the subobject.
for (unsigned I = 0, N = Sub.Entries.size(); /**/; ++I) {
  if (O->isUninit()) {
    if (!Info.checkingPotentialConstantExpression())
      Info.FFDiag(E, diag::note_constexpr_access_uninit) << handler.AccessKind;
    return handler.failed();
  }

  if (I == N) {
    // If we are reading an object of class type, there may still be more
    // things we need to check: if there are any mutable subobjects, we
    // cannot perform this read. (This only happens when performing a trivial
    // copy or assignment.)
    if (ObjType->isRecordType() && handler.AccessKind == AK_Read &&
        !MayReadMutableMembers && diagnoseUnreadableFields(Info, E, ObjType))
      return handler.failed();

    if (!handler.found(*O, ObjType))
      return false;

    // If we modified a bit-field, truncate it to the right width.
    if (handler.AccessKind != AK_Read &&
        LastField && LastField->isBitField() &&
        !truncateBitfieldValue(Info, E, *O, LastField))
      return false;

    return true;
  }

  LastField = nullptr;
  if (ObjType->isArrayType()) {
    // Next subobject is an array element.
    const ConstantArrayType *CAT = Info.Ctx.getAsConstantArrayType(ObjType);
    assert(CAT && "vla in literal type?")(static_cast <bool> (CAT && "vla in literal type?"
) ? void (0) : __assert_fail ("CAT && \"vla in literal type?\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 2721, __extension__ __PRETTY_FUNCTION__));
    uint64_t Index = Sub.Entries[I].ArrayIndex;
    if (CAT->getSize().ule(Index)) {
      // Note, it should not be possible to form a pointer with a valid
      // designator which points more than one past the end of the array.
      if (Info.getLangOpts().CPlusPlus11)
        Info.FFDiag(E, diag::note_constexpr_access_past_end)
          << handler.AccessKind;
      else
        Info.FFDiag(E);
      return handler.failed();
    }

    ObjType = CAT->getElementType();

    // An array object is represented as either an Array APValue or as an
    // LValue which refers to a string literal.
    if (O->isLValue()) {
      assert(I == N - 1 && "extracting subobject of character?")(static_cast <bool> (I == N - 1 && "extracting subobject of character?"
) ? void (0) : __assert_fail ("I == N - 1 && \"extracting subobject of character?\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 2739, __extension__ __PRETTY_FUNCTION__));
      assert(!O->hasLValuePath() || O->getLValuePath().empty())(static_cast <bool> (!O->hasLValuePath() || O->getLValuePath
().empty()) ? void (0) : __assert_fail ("!O->hasLValuePath() || O->getLValuePath().empty()"
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 2740, __extension__ __PRETTY_FUNCTION__));
      if (handler.AccessKind != AK_Read)
        expandStringLiteral(Info, O->getLValueBase().get<const Expr *>(),
                            *O);
      else
        return handler.foundString(*O, ObjType, Index);
    }

    if (O->getArrayInitializedElts() > Index)
      O = &O->getArrayInitializedElt(Index);
    else if (handler.AccessKind != AK_Read) {
      expandArray(*O, Index);
      O = &O->getArrayInitializedElt(Index);
    } else
      O = &O->getArrayFiller();
  } else if (ObjType->isAnyComplexType()) {
    // Next subobject is a complex number.
    uint64_t Index = Sub.Entries[I].ArrayIndex;
    if (Index > 1) {
      if (Info.getLangOpts().CPlusPlus11)
        Info.FFDiag(E, diag::note_constexpr_access_past_end)
          << handler.AccessKind;
      else
        Info.FFDiag(E);
      return handler.failed();
    }

    bool WasConstQualified = ObjType.isConstQualified();
    ObjType = ObjType->castAs<ComplexType>()->getElementType();
    if (WasConstQualified)
      ObjType.addConst();

    assert(I == N - 1 && "extracting subobject of scalar?")(static_cast <bool> (I == N - 1 && "extracting subobject of scalar?"
) ? void (0) : __assert_fail ("I == N - 1 && \"extracting subobject of scalar?\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 2772, __extension__ __PRETTY_FUNCTION__));
    if (O->isComplexInt()) {
      return handler.found(Index ? O->getComplexIntImag()
                                 : O->getComplexIntReal(), ObjType);
    } else {
      assert(O->isComplexFloat())(static_cast <bool> (O->isComplexFloat()) ? void (0)
 : __assert_fail ("O->isComplexFloat()", "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 2777, __extension__ __PRETTY_FUNCTION__));
      return handler.found(Index ? O->getComplexFloatImag()
                                 : O->getComplexFloatReal(), ObjType);
    }
  } else if (const FieldDecl *Field = getAsField(Sub.Entries[I])) {
    // In C++14 onwards, it is permitted to read a mutable member whose
    // lifetime began within the evaluation.
    // FIXME: Should we also allow this in C++11?
    if (Field->isMutable() && handler.AccessKind == AK_Read &&
        !MayReadMutableMembers) {
      Info.FFDiag(E, diag::note_constexpr_ltor_mutable, 1)
        << Field;
      Info.Note(Field->getLocation(), diag::note_declared_at);
      return handler.failed();
    }

    // Next subobject is a class, struct or union field.
    RecordDecl *RD = ObjType->castAs<RecordType>()->getDecl();
    if (RD->isUnion()) {
      const FieldDecl *UnionField = O->getUnionField();
      if (!UnionField ||
          UnionField->getCanonicalDecl() != Field->getCanonicalDecl()) {
        Info.FFDiag(E, diag::note_constexpr_access_inactive_union_member)
          << handler.AccessKind << Field << !UnionField << UnionField;
        return handler.failed();
      }
      O = &O->getUnionValue();
    } else
      O = &O->getStructField(Field->getFieldIndex());

    bool WasConstQualified = ObjType.isConstQualified();
    ObjType = Field->getType();
    if (WasConstQualified && !Field->isMutable())
      ObjType.addConst();

    if (ObjType.isVolatileQualified()) {
      if (Info.getLangOpts().CPlusPlus) {
        // FIXME: Include a description of the path to the volatile subobject.
        Info.FFDiag(E, diag::note_constexpr_access_volatile_obj, 1)
          << handler.AccessKind << 2 << Field;
        Info.Note(Field->getLocation(), diag::note_declared_at);
      } else {
        Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr);
      }
      return handler.failed();
    }

    LastField = Field;
  } else {
    // Next subobject is a base class.
    const CXXRecordDecl *Derived = ObjType->getAsCXXRecordDecl();
    const CXXRecordDecl *Base = getAsBaseClass(Sub.Entries[I]);
    O = &O->getStructBase(getBaseIndex(Derived, Base));

    bool WasConstQualified = ObjType.isConstQualified();
    ObjType = Info.Ctx.getRecordType(Base);
    if (WasConstQualified)
      ObjType.addConst();
  }
}
2837}

2839namespace {
2840struct ExtractSubobjectHandler {
EvalInfo &Info;
APValue &Result;

static const AccessKinds AccessKind = AK_Read;

typedef bool result_type;
bool failed() { return false; }
bool found(APValue &Subobj, QualType SubobjType) {
  Result = Subobj;
  return true;
}
bool found(APSInt &Value, QualType SubobjType) {
  Result = APValue(Value);
  return true;
}
bool found(APFloat &Value, QualType SubobjType) {
  Result = APValue(Value);
  return true;
}
bool foundString(APValue &Subobj, QualType SubobjType, uint64_t Character) {
  Result = APValue(extractStringLiteralCharacter(
      Info, Subobj.getLValueBase().get<const Expr *>(), Character));
  return true;
}
2865};
2866} // end anonymous namespace

2868const AccessKinds ExtractSubobjectHandler::AccessKind;

2870/// Extract the designated sub-object of an rvalue.
2871static bool extractSubobject(EvalInfo &Info, const Expr *E,
                           const CompleteObject &Obj,
                           const SubobjectDesignator &Sub,
                           APValue &Result) {
ExtractSubobjectHandler Handler = { Info, Result };
return findSubobject(Info, E, Obj, Sub, Handler);
2877}

2879namespace {
2880struct ModifySubobjectHandler {
EvalInfo &Info;
APValue &NewVal;
const Expr *E;

typedef bool result_type;
static const AccessKinds AccessKind = AK_Assign;

bool checkConst(QualType QT) {
  // Assigning to a const object has undefined behavior.
  if (QT.isConstQualified()) {
    Info.FFDiag(E, diag::note_constexpr_modify_const_type) << QT;
    return false;
  }
  return true;
}

bool failed() { return false; }
bool found(APValue &Subobj, QualType SubobjType) {
  if (!checkConst(SubobjType))
    return false;
  // We've been given ownership of NewVal, so just swap it in.
  Subobj.swap(NewVal);
  return true;
}
bool found(APSInt &Value, QualType SubobjType) {
  if (!checkConst(SubobjType))
    return false;
  if (!NewVal.isInt()) {
    // Maybe trying to write a cast pointer value into a complex?
    Info.FFDiag(E);
    return false;
  }
  Value = NewVal.getInt();
  return true;
}
bool found(APFloat &Value, QualType SubobjType) {
  if (!checkConst(SubobjType))
    return false;
  Value = NewVal.getFloat();
  return true;
}
bool foundString(APValue &Subobj, QualType SubobjType, uint64_t Character) {
  llvm_unreachable("shouldn't encounter string elements with ExpandArrays")::llvm::llvm_unreachable_internal("shouldn't encounter string elements with ExpandArrays"
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 2923);
}
2925};
2926} // end anonymous namespace

2928const AccessKinds ModifySubobjectHandler::AccessKind;

2930/// Update the designated sub-object of an rvalue to the given value.
2931static bool modifySubobject(EvalInfo &Info, const Expr *E,
                          const CompleteObject &Obj,
                          const SubobjectDesignator &Sub,
                          APValue &NewVal) {
ModifySubobjectHandler Handler = { Info, NewVal, E };
return findSubobject(Info, E, Obj, Sub, Handler);
2937}

2939/// Find the position where two subobject designators diverge, or equivalently
2940/// the length of the common initial subsequence.
2941static unsigned FindDesignatorMismatch(QualType ObjType,
                                     const SubobjectDesignator &A,
                                     const SubobjectDesignator &B,
                                     bool &WasArrayIndex) {
unsigned I = 0, N = std::min(A.Entries.size(), B.Entries.size());
for (/**/; I != N; ++I) {
  if (!ObjType.isNull() &&
      (ObjType->isArrayType() || ObjType->isAnyComplexType())) {
    // Next subobject is an array element.
    if (A.Entries[I].ArrayIndex != B.Entries[I].ArrayIndex) {
      WasArrayIndex = true;
      return I;
    }
    if (ObjType->isAnyComplexType())
      ObjType = ObjType->castAs<ComplexType>()->getElementType();
    else
      ObjType = ObjType->castAsArrayTypeUnsafe()->getElementType();
  } else {
    if (A.Entries[I].BaseOrMember != B.Entries[I].BaseOrMember) {
      WasArrayIndex = false;
      return I;
    }
    if (const FieldDecl *FD = getAsField(A.Entries[I]))
      // Next subobject is a field.
      ObjType = FD->getType();
    else
      // Next subobject is a base class.
      ObjType = QualType();
  }
}
WasArrayIndex = false;
return I;
2973}

2975/// Determine whether the given subobject designators refer to elements of the
2976/// same array object.
2977static bool AreElementsOfSameArray(QualType ObjType,
                                 const SubobjectDesignator &A,
                                 const SubobjectDesignator &B) {
if (A.Entries.size() != B.Entries.size())
  return false;

bool IsArray = A.MostDerivedIsArrayElement;
if (IsArray && A.MostDerivedPathLength != A.Entries.size())
  // A is a subobject of the array element.
  return false;

// If A (and B) designates an array element, the last entry will be the array
// index. That doesn't have to match. Otherwise, we're in the 'implicit array
// of length 1' case, and the entire path must match.
bool WasArrayIndex;
unsigned CommonLength = FindDesignatorMismatch(ObjType, A, B, WasArrayIndex);
return CommonLength >= A.Entries.size() - IsArray;
2994}

2996/// Find the complete object to which an LValue refers.
2997static CompleteObject findCompleteObject(EvalInfo &Info, const Expr *E,
                                       AccessKinds AK, const LValue &LVal,
                                       QualType LValType) {
if (!LVal.Base) {
  Info.FFDiag(E, diag::note_constexpr_access_null) << AK;
  return CompleteObject();
}

CallStackFrame *Frame = nullptr;
if (LVal.CallIndex) {
  Frame = Info.getCallFrame(LVal.CallIndex);
  if (!Frame) {
    Info.FFDiag(E, diag::note_constexpr_lifetime_ended, 1)
      << AK << LVal.Base.is<const ValueDecl*>();
    NoteLValueLocation(Info, LVal.Base);
    return CompleteObject();
  }
}

// C++11 DR1311: An lvalue-to-rvalue conversion on a volatile-qualified type
// is not a constant expression (even if the object is non-volatile). We also
// apply this rule to C++98, in order to conform to the expected 'volatile'
// semantics.
if (LValType.isVolatileQualified()) {
  if (Info.getLangOpts().CPlusPlus)
    Info.FFDiag(E, diag::note_constexpr_access_volatile_type)
      << AK << LValType;
  else
    Info.FFDiag(E);
  return CompleteObject();
}

// Compute value storage location and type of base object.
APValue *BaseVal = nullptr;
QualType BaseType = getType(LVal.Base);
bool LifetimeStartedInEvaluation = Frame;

if (const ValueDecl *D = LVal.Base.dyn_cast<const ValueDecl*>()) {
  // In C++98, const, non-volatile integers initialized with ICEs are ICEs.
  // In C++11, constexpr, non-volatile variables initialized with constant
  // expressions are constant expressions too. Inside constexpr functions,
  // parameters are constant expressions even if they're non-const.
  // In C++1y, objects local to a constant expression (those with a Frame) are
  // both readable and writable inside constant expressions.
  // In C, such things can also be folded, although they are not ICEs.
  const VarDecl *VD = dyn_cast<VarDecl>(D);
  if (VD) {
    if (const VarDecl *VDef = VD->getDefinition(Info.Ctx))
      VD = VDef;
  }
  if (!VD || VD->isInvalidDecl()) {
    Info.FFDiag(E);
    return CompleteObject();
  }

  // Accesses of volatile-qualified objects are not allowed.
  if (BaseType.isVolatileQualified()) {
    if (Info.getLangOpts().CPlusPlus) {
      Info.FFDiag(E, diag::note_constexpr_access_volatile_obj, 1)
        << AK << 1 << VD;
      Info.Note(VD->getLocation(), diag::note_declared_at);
    } else {
      Info.FFDiag(E);
    }
    return CompleteObject();
  }

  // Unless we're looking at a local variable or argument in a constexpr call,
  // the variable we're reading must be const.
  if (!Frame) {
    if (Info.getLangOpts().CPlusPlus14 &&
        VD == Info.EvaluatingDecl.dyn_cast<const ValueDecl *>()) {
      // OK, we can read and modify an object if we're in the process of
      // evaluating its initializer, because its lifetime began in this
      // evaluation.
    } else if (AK != AK_Read) {
      // All the remaining cases only permit reading.
      Info.FFDiag(E, diag::note_constexpr_modify_global);
      return CompleteObject();
    } else if (VD->isConstexpr()) {
      // OK, we can read this variable.
    } else if (BaseType->isIntegralOrEnumerationType()) {
      // In OpenCL if a variable is in constant address space it is a const value.
      if (!(BaseType.isConstQualified() ||
            (Info.getLangOpts().OpenCL &&
             BaseType.getAddressSpace() == LangAS::opencl_constant))) {
        if (Info.getLangOpts().CPlusPlus) {
          Info.FFDiag(E, diag::note_constexpr_ltor_non_const_int, 1) << VD;
          Info.Note(VD->getLocation(), diag::note_declared_at);
        } else {
          Info.FFDiag(E);
        }
        return CompleteObject();
      }
    } else if (BaseType->isFloatingType() && BaseType.isConstQualified()) {
      // We support folding of const floating-point types, in order to make
      // static const data members of such types (supported as an extension)
      // more useful.
      if (Info.getLangOpts().CPlusPlus11) {
        Info.CCEDiag(E, diag::note_constexpr_ltor_non_constexpr, 1) << VD;
        Info.Note(VD->getLocation(), diag::note_declared_at);
      } else {
        Info.CCEDiag(E);
      }
    } else if (BaseType.isConstQualified() && VD->hasDefinition(Info.Ctx)) {
      Info.CCEDiag(E, diag::note_constexpr_ltor_non_constexpr) << VD;
      // Keep evaluating to see what we can do.
    } else {
      // FIXME: Allow folding of values of any literal type in all languages.
      if (Info.checkingPotentialConstantExpression() &&
          VD->getType().isConstQualified() && !VD->hasDefinition(Info.Ctx)) {
        // The definition of this variable could be constexpr. We can't
        // access it right now, but may be able to in future.
      } else if (Info.getLangOpts().CPlusPlus11) {
        Info.FFDiag(E, diag::note_constexpr_ltor_non_constexpr, 1) << VD;
        Info.Note(VD->getLocation(), diag::note_declared_at);
      } else {
        Info.FFDiag(E);
      }
      return CompleteObject();
    }
  }

  if (!evaluateVarDeclInit(Info, E, VD, Frame, BaseVal))
    return CompleteObject();
} else {
  const Expr *Base = LVal.Base.dyn_cast<const Expr*>();

  if (!Frame) {
    if (const MaterializeTemporaryExpr *MTE =
            dyn_cast<MaterializeTemporaryExpr>(Base)) {
      assert(MTE->getStorageDuration() == SD_Static &&(static_cast <bool> (MTE->getStorageDuration() == SD_Static
 && "should have a frame for a non-global materialized temporary"
) ? void (0) : __assert_fail ("MTE->getStorageDuration() == SD_Static && \"should have a frame for a non-global materialized temporary\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 3129, __extension__ __PRETTY_FUNCTION__))
             "should have a frame for a non-global materialized temporary")(static_cast <bool> (MTE->getStorageDuration() == SD_Static
 && "should have a frame for a non-global materialized temporary"
) ? void (0) : __assert_fail ("MTE->getStorageDuration() == SD_Static && \"should have a frame for a non-global materialized temporary\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 3129, __extension__ __PRETTY_FUNCTION__));

      // Per C++1y [expr.const]p2:
      //  an lvalue-to-rvalue conversion [is not allowed unless it applies to]
      //   - a [...] glvalue of integral or enumeration type that refers to
      //     a non-volatile const object [...]
      //   [...]
      //   - a [...] glvalue of literal type that refers to a non-volatile
      //     object whose lifetime began within the evaluation of e.
      //
      // C++11 misses the 'began within the evaluation of e' check and
      // instead allows all temporaries, including things like:
      //   int &&r = 1;
      //   int x = ++r;
      //   constexpr int k = r;
      // Therefore we use the C++14 rules in C++11 too.
      const ValueDecl *VD = Info.EvaluatingDecl.dyn_cast<const ValueDecl*>();
      const ValueDecl *ED = MTE->getExtendingDecl();
      if (!(BaseType.isConstQualified() &&
            BaseType->isIntegralOrEnumerationType()) &&
          !(VD && VD->getCanonicalDecl() == ED->getCanonicalDecl())) {
        Info.FFDiag(E, diag::note_constexpr_access_static_temporary, 1) << AK;
        Info.Note(MTE->getExprLoc(), diag::note_constexpr_temporary_here);
        return CompleteObject();
      }

      BaseVal = Info.Ctx.getMaterializedTemporaryValue(MTE, false);
      assert(BaseVal && "got reference to unevaluated temporary")(static_cast <bool> (BaseVal && "got reference to unevaluated temporary"
) ? void (0) : __assert_fail ("BaseVal && \"got reference to unevaluated temporary\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 3156, __extension__ __PRETTY_FUNCTION__));
      LifetimeStartedInEvaluation = true;
    } else {
      Info.FFDiag(E);
      return CompleteObject();
    }
  } else {
    BaseVal = Frame->getTemporary(Base);
    assert(BaseVal && "missing value for temporary")(static_cast <bool> (BaseVal && "missing value for temporary"
) ? void (0) : __assert_fail ("BaseVal && \"missing value for temporary\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 3164, __extension__ __PRETTY_FUNCTION__));
  }

  // Volatile temporary objects cannot be accessed in constant expressions.
  if (BaseType.isVolatileQualified()) {
    if (Info.getLangOpts().CPlusPlus) {
      Info.FFDiag(E, diag::note_constexpr_access_volatile_obj, 1)
        << AK << 0;
      Info.Note(Base->getExprLoc(), diag::note_constexpr_temporary_here);
    } else {
      Info.FFDiag(E);
    }
    return CompleteObject();
  }
}

// During the construction of an object, it is not yet 'const'.
// FIXME: This doesn't do quite the right thing for const subobjects of the
// object under construction.
if (Info.isEvaluatingConstructor(LVal.getLValueBase(), LVal.CallIndex)) {
  BaseType = Info.Ctx.getCanonicalType(BaseType);
  BaseType.removeLocalConst();
  LifetimeStartedInEvaluation = true;
}

// In C++14, we can't safely access any mutable state when we might be
// evaluating after an unmodeled side effect.
//
// FIXME: Not all local state is mutable. Allow local constant subobjects
// to be read here (but take care with 'mutable' fields).
if ((Frame && Info.getLangOpts().CPlusPlus14 &&
     Info.EvalStatus.HasSideEffects) ||
    (AK != AK_Read && Info.IsSpeculativelyEvaluating))
  return CompleteObject();

return CompleteObject(BaseVal, BaseType, LifetimeStartedInEvaluation);
3200}

3202/// \brief Perform an lvalue-to-rvalue conversion on the given glvalue. This
3203/// can also be used for 'lvalue-to-lvalue' conversions for looking up the
3204/// glvalue referred to by an entity of reference type.
3205///
3206/// \param Info - Information about the ongoing evaluation.
3207/// \param Conv - The expression for which we are performing the conversion.
3208///               Used for diagnostics.
3209/// \param Type - The type of the glvalue (before stripping cv-qualifiers in the
3210///               case of a non-class type).
3211/// \param LVal - The glvalue on which we are attempting to perform this action.
3212/// \param RVal - The produced value will be placed here.
3213static bool handleLValueToRValueConversion(EvalInfo &Info, const Expr *Conv,
                                         QualType Type,
                                         const LValue &LVal, APValue &RVal) {
if (LVal.Designator.Invalid)
  return false;

// Check for special cases where there is no existing APValue to look at.
const Expr *Base = LVal.Base.dyn_cast<const Expr*>();
if (Base && !LVal.CallIndex && !Type.isVolatileQualified()) {
  if (const CompoundLiteralExpr *CLE = dyn_cast<CompoundLiteralExpr>(Base)) {
    // In C99, a CompoundLiteralExpr is an lvalue, and we defer evaluating the
    // initializer until now for such expressions. Such an expression can't be
    // an ICE in C, so this only matters for fold.
    if (Type.isVolatileQualified()) {
      Info.FFDiag(Conv);
      return false;
    }
    APValue Lit;
    if (!Evaluate(Lit, Info, CLE->getInitializer()))
      return false;
    CompleteObject LitObj(&Lit, Base->getType(), false);
    return extractSubobject(Info, Conv, LitObj, LVal.Designator, RVal);
  } else if (isa<StringLiteral>(Base) || isa<PredefinedExpr>(Base)) {
    // We represent a string literal array as an lvalue pointing at the
    // corresponding expression, rather than building an array of chars.
    // FIXME: Support ObjCEncodeExpr, MakeStringConstant
    APValue Str(Base, CharUnits::Zero(), APValue::NoLValuePath(), 0);
    CompleteObject StrObj(&Str, Base->getType(), false);
    return extractSubobject(Info, Conv, StrObj, LVal.Designator, RVal);
  }
}

CompleteObject Obj = findCompleteObject(Info, Conv, AK_Read, LVal, Type);
return Obj && extractSubobject(Info, Conv, Obj, LVal.Designator, RVal);
3247}

3249/// Perform an assignment of Val to LVal. Takes ownership of Val.
3250static bool handleAssignment(EvalInfo &Info, const Expr *E, const LValue &LVal,
                           QualType LValType, APValue &Val) {
if (LVal.Designator.Invalid)
  return false;

if (!Info.getLangOpts().CPlusPlus14) {
  Info.FFDiag(E);
  return false;
}

CompleteObject Obj = findCompleteObject(Info, E, AK_Assign, LVal, LValType);
return Obj && modifySubobject(Info, E, Obj, LVal.Designator, Val);
3262}
3263
3264namespace {
3265struct CompoundAssignSubobjectHandler {
EvalInfo &Info;
const Expr *E;
QualType PromotedLHSType;
BinaryOperatorKind Opcode;
const APValue &RHS;

static const AccessKinds AccessKind = AK_Assign;

typedef bool result_type;

bool checkConst(QualType QT) {
  // Assigning to a const object has undefined behavior.
  if (QT.isConstQualified()) {
    Info.FFDiag(E, diag::note_constexpr_modify_const_type) << QT;
    return false;
  }
  return true;
}

bool failed() { return false; }
bool found(APValue &Subobj, QualType SubobjType) {
  switch (Subobj.getKind()) {
  case APValue::Int:
    return found(Subobj.getInt(), SubobjType);
  case APValue::Float:
    return found(Subobj.getFloat(), SubobjType);
  case APValue::ComplexInt:
  case APValue::ComplexFloat:
    // FIXME: Implement complex compound assignment.
    Info.FFDiag(E);
    return false;
  case APValue::LValue:
    return foundPointer(Subobj, SubobjType);
  default:
    // FIXME: can this happen?
    Info.FFDiag(E);
    return false;
  }
}
bool found(APSInt &Value, QualType SubobjType) {
  if (!checkConst(SubobjType))
    return false;

  if (!SubobjType->isIntegerType() || !RHS.isInt()) {
    // We don't support compound assignment on integer-cast-to-pointer
    // values.
    Info.FFDiag(E);
    return false;
  }

  APSInt LHS = HandleIntToIntCast(Info, E, PromotedLHSType,
                                  SubobjType, Value);
  if (!handleIntIntBinOp(Info, E, LHS, Opcode, RHS.getInt(), LHS))
    return false;
  Value = HandleIntToIntCast(Info, E, SubobjType, PromotedLHSType, LHS);
  return true;
}
bool found(APFloat &Value, QualType SubobjType) {
  return checkConst(SubobjType) &&
         HandleFloatToFloatCast(Info, E, SubobjType, PromotedLHSType,
                                Value) &&
         handleFloatFloatBinOp(Info, E, Value, Opcode, RHS.getFloat()) &&
         HandleFloatToFloatCast(Info, E, PromotedLHSType, SubobjType, Value);
}
bool foundPointer(APValue &Subobj, QualType SubobjType) {
  if (!checkConst(SubobjType))
    return false;

  QualType PointeeType;
  if (const PointerType *PT = SubobjType->getAs<PointerType>())
    PointeeType = PT->getPointeeType();

  if (PointeeType.isNull() || !RHS.isInt() ||
      (Opcode != BO_Add && Opcode != BO_Sub)) {
    Info.FFDiag(E);
    return false;
  }

  APSInt Offset = RHS.getInt();
  if (Opcode == BO_Sub)
    negateAsSigned(Offset);

  LValue LVal;
  LVal.setFrom(Info.Ctx, Subobj);
  if (!HandleLValueArrayAdjustment(Info, E, LVal, PointeeType, Offset))
    return false;
  LVal.moveInto(Subobj);
  return true;
}
bool foundString(APValue &Subobj, QualType SubobjType, uint64_t Character) {
  llvm_unreachable("shouldn't encounter string elements here")::llvm::llvm_unreachable_internal("shouldn't encounter string elements here"
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 3356);
}
3358};
3359} // end anonymous namespace

3361const AccessKinds CompoundAssignSubobjectHandler::AccessKind;

3363/// Perform a compound assignment of LVal <op>= RVal.
3364static bool handleCompoundAssignment(
  EvalInfo &Info, const Expr *E,
  const LValue &LVal, QualType LValType, QualType PromotedLValType,
  BinaryOperatorKind Opcode, const APValue &RVal) {
if (LVal.Designator.Invalid)
  return false;

if (!Info.getLangOpts().CPlusPlus14) {
  Info.FFDiag(E);
  return false;
}

CompleteObject Obj = findCompleteObject(Info, E, AK_Assign, LVal, LValType);
CompoundAssignSubobjectHandler Handler = { Info, E, PromotedLValType, Opcode,
                                           RVal };
return Obj && findSubobject(Info, E, Obj, LVal.Designator, Handler);
3380}

3382namespace {
3383struct IncDecSubobjectHandler {
EvalInfo &Info;
const UnaryOperator *E;
AccessKinds AccessKind;
APValue *Old;
3388
typedef bool result_type;

bool checkConst(QualType QT) {
  // Assigning to a const object has undefined behavior.
  if (QT.isConstQualified()) {
    Info.FFDiag(E, diag::note_constexpr_modify_const_type) << QT;
    return false;
  }
  return true;
}

bool failed() { return false; }
bool found(APValue &Subobj, QualType SubobjType) {
  // Stash the old value. Also clear Old, so we don't clobber it later
  // if we're post-incrementing a complex.
  if (Old) {
    *Old = Subobj;
    Old = nullptr;
  }

  switch (Subobj.getKind()) {
  case APValue::Int:
    return found(Subobj.getInt(), SubobjType);
  case APValue::Float:
    return found(Subobj.getFloat(), SubobjType);
  case APValue::ComplexInt:
    return found(Subobj.getComplexIntReal(),
                 SubobjType->castAs<ComplexType>()->getElementType()
                   .withCVRQualifiers(SubobjType.getCVRQualifiers()));
  case APValue::ComplexFloat:
    return found(Subobj.getComplexFloatReal(),
                 SubobjType->castAs<ComplexType>()->getElementType()
                   .withCVRQualifiers(SubobjType.getCVRQualifiers()));
  case APValue::LValue:
    return foundPointer(Subobj, SubobjType);
  default:
    // FIXME: can this happen?
    Info.FFDiag(E);
    return false;
  }
}
bool found(APSInt &Value, QualType SubobjType) {
  if (!checkConst(SubobjType))
    return false;

  if (!SubobjType->isIntegerType()) {
    // We don't support increment / decrement on integer-cast-to-pointer
    // values.
    Info.FFDiag(E);
    return false;
  }

  if (Old) *Old = APValue(Value);

  // bool arithmetic promotes to int, and the conversion back to bool
  // doesn't reduce mod 2^n, so special-case it.
  if (SubobjType->isBooleanType()) {
    if (AccessKind == AK_Increment)
      Value = 1;
    else
      Value = !Value;
    return true;
  }

  bool WasNegative = Value.isNegative();
  if (AccessKind == AK_Increment) {
    ++Value;
3456
    if (!WasNegative && Value.isNegative() && E->canOverflow()) {
      APSInt ActualValue(Value, /*IsUnsigned*/true);
      return HandleOverflow(Info, E, ActualValue, SubobjType);
    }
  } else {
    --Value;
3463
    if (WasNegative && !Value.isNegative() && E->canOverflow()) {
      unsigned BitWidth = Value.getBitWidth();
      APSInt ActualValue(Value.sext(BitWidth + 1), /*IsUnsigned*/false);
      ActualValue.setBit(BitWidth);
      return HandleOverflow(Info, E, ActualValue, SubobjType);
    }
  }
  return true;
}
bool found(APFloat &Value, QualType SubobjType) {
  if (!checkConst(SubobjType))
    return false;

  if (Old) *Old = APValue(Value);

  APFloat One(Value.getSemantics(), 1);
  if (AccessKind == AK_Increment)
    Value.add(One, APFloat::rmNearestTiesToEven);
  else
    Value.subtract(One, APFloat::rmNearestTiesToEven);
  return true;
}
bool foundPointer(APValue &Subobj, QualType SubobjType) {
  if (!checkConst(SubobjType))
    return false;

  QualType PointeeType;
  if (const PointerType *PT = SubobjType->getAs<PointerType>())
    PointeeType = PT->getPointeeType();
  else {
    Info.FFDiag(E);
    return false;
  }

  LValue LVal;
  LVal.setFrom(Info.Ctx, Subobj);
  if (!HandleLValueArrayAdjustment(Info, E, LVal, PointeeType,
                                   AccessKind == AK_Increment ? 1 : -1))
    return false;
  LVal.moveInto(Subobj);
  return true;
}
bool foundString(APValue &Subobj, QualType SubobjType, uint64_t Character) {
  llvm_unreachable("shouldn't encounter string elements here")::llvm::llvm_unreachable_internal("shouldn't encounter string elements here"
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 3507);
}
3509};
3510} // end anonymous namespace

3512/// Perform an increment or decrement on LVal.
3513static bool handleIncDec(EvalInfo &Info, const Expr *E, const LValue &LVal,
                       QualType LValType, bool IsIncrement, APValue *Old) {
if (LVal.Designator.Invalid)
  return false;

if (!Info.getLangOpts().CPlusPlus14) {
  Info.FFDiag(E);
  return false;
}
3522
AccessKinds AK = IsIncrement ? AK_Increment : AK_Decrement;
CompleteObject Obj = findCompleteObject(Info, E, AK, LVal, LValType);
IncDecSubobjectHandler Handler = {Info, cast<UnaryOperator>(E), AK, Old};
return Obj && findSubobject(Info, E, Obj, LVal.Designator, Handler);
3527}
3528
3529/// Build an lvalue for the object argument of a member function call.
3530static bool EvaluateObjectArgument(EvalInfo &Info, const Expr *Object,
                                 LValue &This) {
if (Object->getType()->isPointerType())
  return EvaluatePointer(Object, This, Info);

if (Object->isGLValue())
  return EvaluateLValue(Object, This, Info);

if (Object->getType()->isLiteralType(Info.Ctx))
  return EvaluateTemporary(Object, This, Info);

Info.FFDiag(Object, diag::note_constexpr_nonliteral) << Object->getType();
return false;
3543}

3545/// HandleMemberPointerAccess - Evaluate a member access operation and build an
3546/// lvalue referring to the result.
3547///
3548/// \param Info - Information about the ongoing evaluation.
3549/// \param LV - An lvalue referring to the base of the member pointer.
3550/// \param RHS - The member pointer expression.
3551/// \param IncludeMember - Specifies whether the member itself is included in
3552///        the resulting LValue subobject designator. This is not possible when
3553///        creating a bound member function.
3554/// \return The field or method declaration to which the member pointer refers,
3555///         or 0 if evaluation fails.
3556static const ValueDecl *HandleMemberPointerAccess(EvalInfo &Info,
                                                QualType LVType,
                                                LValue &LV,
                                                const Expr *RHS,
                                                bool IncludeMember = true) {
MemberPtr MemPtr;
if (!EvaluateMemberPointer(RHS, MemPtr, Info))
  return nullptr;

// C++11 [expr.mptr.oper]p6: If the second operand is the null pointer to
// member value, the behavior is undefined.
if (!MemPtr.getDecl()) {
  // FIXME: Specific diagnostic.
  Info.FFDiag(RHS);
  return nullptr;
}

if (MemPtr.isDerivedMember()) {
  // This is a member of some derived class. Truncate LV appropriately.
  // The end of the derived-to-base path for the base object must match the
  // derived-to-base path for the member pointer.
  if (LV.Designator.MostDerivedPathLength + MemPtr.Path.size() >
      LV.Designator.Entries.size()) {
    Info.FFDiag(RHS);
    return nullptr;
  }
  unsigned PathLengthToMember =
      LV.Designator.Entries.size() - MemPtr.Path.size();
  for (unsigned I = 0, N = MemPtr.Path.size(); I != N; ++I) {
    const CXXRecordDecl *LVDecl = getAsBaseClass(
        LV.Designator.Entries[PathLengthToMember + I]);
    const CXXRecordDecl *MPDecl = MemPtr.Path[I];
    if (LVDecl->getCanonicalDecl() != MPDecl->getCanonicalDecl()) {
      Info.FFDiag(RHS);
      return nullptr;
    }
  }

  // Truncate the lvalue to the appropriate derived class.
  if (!CastToDerivedClass(Info, RHS, LV, MemPtr.getContainingRecord(),
                          PathLengthToMember))
    return nullptr;
} else if (!MemPtr.Path.empty()) {
  // Extend the LValue path with the member pointer's path.
  LV.Designator.Entries.reserve(LV.Designator.Entries.size() +
                                MemPtr.Path.size() + IncludeMember);

  // Walk down to the appropriate base class.
  if (const PointerType *PT = LVType->getAs<PointerType>())
    LVType = PT->getPointeeType();
  const CXXRecordDecl *RD = LVType->getAsCXXRecordDecl();
  assert(RD && "member pointer access on non-class-type expression")(static_cast <bool> (RD && "member pointer access on non-class-type expression"
) ? void (0) : __assert_fail ("RD && \"member pointer access on non-class-type expression\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 3607, __extension__ __PRETTY_FUNCTION__));
  // The first class in the path is that of the lvalue.
  for (unsigned I = 1, N = MemPtr.Path.size(); I != N; ++I) {
    const CXXRecordDecl *Base = MemPtr.Path[N - I - 1];
    if (!HandleLValueDirectBase(Info, RHS, LV, RD, Base))
      return nullptr;
    RD = Base;
  }
  // Finally cast to the class containing the member.
  if (!HandleLValueDirectBase(Info, RHS, LV, RD,
                              MemPtr.getContainingRecord()))
    return nullptr;
}

// Add the member. Note that we cannot build bound member functions here.
if (IncludeMember) {
  if (const FieldDecl *FD = dyn_cast<FieldDecl>(MemPtr.getDecl())) {
    if (!HandleLValueMember(Info, RHS, LV, FD))
      return nullptr;
  } else if (const IndirectFieldDecl *IFD =
               dyn_cast<IndirectFieldDecl>(MemPtr.getDecl())) {
    if (!HandleLValueIndirectMember(Info, RHS, LV, IFD))
      return nullptr;
  } else {
    llvm_unreachable("can't construct reference to bound member function")::llvm::llvm_unreachable_internal("can't construct reference to bound member function"
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 3631);
  }
}

return MemPtr.getDecl();
3636}

3638static const ValueDecl *HandleMemberPointerAccess(EvalInfo &Info,
                                                const BinaryOperator *BO,
                                                LValue &LV,
                                                bool IncludeMember = true) {
assert(BO->getOpcode() == BO_PtrMemD || BO->getOpcode() == BO_PtrMemI)(static_cast <bool> (BO->getOpcode() == BO_PtrMemD ||
 BO->getOpcode() == BO_PtrMemI) ? void (0) : __assert_fail
 ("BO->getOpcode() == BO_PtrMemD || BO->getOpcode() == BO_PtrMemI"
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 3642, __extension__ __PRETTY_FUNCTION__));

if (!EvaluateObjectArgument(Info, BO->getLHS(), LV)) {
  if (Info.noteFailure()) {
    MemberPtr MemPtr;
    EvaluateMemberPointer(BO->getRHS(), MemPtr, Info);
  }
  return nullptr;
}

return HandleMemberPointerAccess(Info, BO->getLHS()->getType(), LV,
                                 BO->getRHS(), IncludeMember);
3654}

3656/// HandleBaseToDerivedCast - Apply the given base-to-derived cast operation on
3657/// the provided lvalue, which currently refers to the base object.
3658static bool HandleBaseToDerivedCast(EvalInfo &Info, const CastExpr *E,
                                  LValue &Result) {
SubobjectDesignator &D = Result.Designator;
if (D.Invalid || !Result.checkNullPointer(Info, E, CSK_Derived))
  return false;

QualType TargetQT = E->getType();
if (const PointerType *PT = TargetQT->getAs<PointerType>())
  TargetQT = PT->getPointeeType();

// Check this cast lands within the final derived-to-base subobject path.
if (D.MostDerivedPathLength + E->path_size() > D.Entries.size()) {
  Info.CCEDiag(E, diag::note_constexpr_invalid_downcast)
    << D.MostDerivedType << TargetQT;
  return false;
}

// Check the type of the final cast. We don't need to check the path,
// since a cast can only be formed if the path is unique.
unsigned NewEntriesSize = D.Entries.size() - E->path_size();
const CXXRecordDecl *TargetType = TargetQT->getAsCXXRecordDecl();
const CXXRecordDecl *FinalType;
if (NewEntriesSize == D.MostDerivedPathLength)
  FinalType = D.MostDerivedType->getAsCXXRecordDecl();
else
  FinalType = getAsBaseClass(D.Entries[NewEntriesSize - 1]);
if (FinalType->getCanonicalDecl() != TargetType->getCanonicalDecl()) {
  Info.CCEDiag(E, diag::note_constexpr_invalid_downcast)
    << D.MostDerivedType << TargetQT;
  return false;
}

// Truncate the lvalue to the appropriate derived class.
return CastToDerivedClass(Info, E, Result, TargetType, NewEntriesSize);
3692}

3694namespace {
3695enum EvalStmtResult {
/// Evaluation failed.
ESR_Failed,
/// Hit a 'return' statement.
ESR_Returned,
/// Evaluation succeeded.
ESR_Succeeded,
/// Hit a 'continue' statement.
ESR_Continue,
/// Hit a 'break' statement.
ESR_Break,
/// Still scanning for 'case' or 'default' statement.
ESR_CaseNotFound
3708};
3709}

3711static bool EvaluateVarDecl(EvalInfo &Info, const VarDecl *VD) {
// We don't need to evaluate the initializer for a static local.
if (!VD->hasLocalStorage())
  return true;

LValue Result;
Result.set(VD, Info.CurrentCall->Index);
APValue &Val = Info.CurrentCall->createTemporary(VD, true);

const Expr *InitE = VD->getInit();
if (!InitE) {
  Info.FFDiag(VD->getLocStart(), diag::note_constexpr_uninitialized)
    << false << VD->getType();
  Val = APValue();
  return false;
}

if (InitE->isValueDependent())
  return false;

if (!EvaluateInPlace(Val, Info, Result, InitE)) {
  // Wipe out any partially-computed value, to allow tracking that this
  // evaluation failed.
  Val = APValue();
  return false;
}

return true;
3739}

3741static bool EvaluateDecl(EvalInfo &Info, const Decl *D) {
bool OK = true;

if (const VarDecl *VD = dyn_cast<VarDecl>(D))
  OK &= EvaluateVarDecl(Info, VD);

if (const DecompositionDecl *DD = dyn_cast<DecompositionDecl>(D))
  for (auto *BD : DD->bindings())
    if (auto *VD = BD->getHoldingVar())
      OK &= EvaluateDecl(Info, VD);

return OK;
3753}


3756/// Evaluate a condition (either a variable declaration or an expression).
3757static bool EvaluateCond(EvalInfo &Info, const VarDecl *CondDecl,
                       const Expr *Cond, bool &Result) {
FullExpressionRAII Scope(Info);
if (CondDecl && !EvaluateDecl(Info, CondDecl))
  return false;
return EvaluateAsBooleanCondition(Cond, Result, Info);
3763}

3765namespace {
3766/// \brief A location where the result (returned value) of evaluating a
3767/// statement should be stored.
3768struct StmtResult {
/// The APValue that should be filled in with the returned value.
APValue &Value;
/// The location containing the result, if any (used to support RVO).
const LValue *Slot;
3773};
3774}

3776static EvalStmtResult EvaluateStmt(StmtResult &Result, EvalInfo &Info,
                                 const Stmt *S,
                                 const SwitchCase *SC = nullptr);

3780/// Evaluate the body of a loop, and translate the result as appropriate.
3781static EvalStmtResult EvaluateLoopBody(StmtResult &Result, EvalInfo &Info,
                                     const Stmt *Body,
                                     const SwitchCase *Case = nullptr) {
BlockScopeRAII Scope(Info);
switch (EvalStmtResult ESR = EvaluateStmt(Result, Info, Body, Case)) {
case ESR_Break:
  return ESR_Succeeded;
case ESR_Succeeded:
case ESR_Continue:
  return ESR_Continue;
case ESR_Failed:
case ESR_Returned:
case ESR_CaseNotFound:
  return ESR;
}
llvm_unreachable("Invalid EvalStmtResult!")::llvm::llvm_unreachable_internal("Invalid EvalStmtResult!", "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 3796);
3797}

3799/// Evaluate a switch statement.
3800static EvalStmtResult EvaluateSwitch(StmtResult &Result, EvalInfo &Info,
                                   const SwitchStmt *SS) {
BlockScopeRAII Scope(Info);

// Evaluate the switch condition.
APSInt Value;
{
  FullExpressionRAII Scope(Info);
  if (const Stmt *Init = SS->getInit()) {
    EvalStmtResult ESR = EvaluateStmt(Result, Info, Init);
    if (ESR != ESR_Succeeded)
      return ESR;
  }
  if (SS->getConditionVariable() &&
      !EvaluateDecl(Info, SS->getConditionVariable()))
    return ESR_Failed;
  if (!EvaluateInteger(SS->getCond(), Value, Info))
    return ESR_Failed;
}

// Find the switch case corresponding to the value of the condition.
// FIXME: Cache this lookup.
const SwitchCase *Found = nullptr;
for (const SwitchCase *SC = SS->getSwitchCaseList(); SC;
     SC = SC->getNextSwitchCase()) {
  if (isa<DefaultStmt>(SC)) {
    Found = SC;
    continue;
  }

  const CaseStmt *CS = cast<CaseStmt>(SC);
  APSInt LHS = CS->getLHS()->EvaluateKnownConstInt(Info.Ctx);
  APSInt RHS = CS->getRHS() ? CS->getRHS()->EvaluateKnownConstInt(Info.Ctx)
                            : LHS;
  if (LHS <= Value && Value <= RHS) {
    Found = SC;
    break;
  }
}

if (!Found)
  return ESR_Succeeded;

// Search the switch body for the switch case and evaluate it from there.
switch (EvalStmtResult ESR = EvaluateStmt(Result, Info, SS->getBody(), Found)) {
case ESR_Break:
  return ESR_Succeeded;
case ESR_Succeeded:
case ESR_Continue:
case ESR_Failed:
case ESR_Returned:
  return ESR;
case ESR_CaseNotFound:
  // This can only happen if the switch case is nested within a statement
  // expression. We have no intention of supporting that.
  Info.FFDiag(Found->getLocStart(), diag::note_constexpr_stmt_expr_unsupported);
  return ESR_Failed;
}
llvm_unreachable("Invalid EvalStmtResult!")::llvm::llvm_unreachable_internal("Invalid EvalStmtResult!", "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 3858);
3859}

3861// Evaluate a statement.
3862static EvalStmtResult EvaluateStmt(StmtResult &Result, EvalInfo &Info,
                                 const Stmt *S, const SwitchCase *Case) {
if (!Info.nextStep(S))
  return ESR_Failed;

// If we're hunting down a 'case' or 'default' label, recurse through
// substatements until we hit the label.
if (Case) {
  // FIXME: We don't start the lifetime of objects whose initialization we
  // jump over. However, such objects must be of class type with a trivial
  // default constructor that initialize all subobjects, so must be empty,
  // so this almost never matters.
  switch (S->getStmtClass()) {
  case Stmt::CompoundStmtClass:
    // FIXME: Precompute which substatement of a compound statement we
    // would jump to, and go straight there rather than performing a
    // linear scan each time.
  case Stmt::LabelStmtClass:
  case Stmt::AttributedStmtClass:
  case Stmt::DoStmtClass:
    break;

  case Stmt::CaseStmtClass:
  case Stmt::DefaultStmtClass:
    if (Case == S)
      Case = nullptr;
    break;

  case Stmt::IfStmtClass: {
    // FIXME: Precompute which side of an 'if' we would jump to, and go
    // straight there rather than scanning both sides.
    const IfStmt *IS = cast<IfStmt>(S);

    // Wrap the evaluation in a block scope, in case it's a DeclStmt
    // preceded by our switch label.
    BlockScopeRAII Scope(Info);

    EvalStmtResult ESR = EvaluateStmt(Result, Info, IS->getThen(), Case);
    if (ESR != ESR_CaseNotFound || !IS->getElse())
      return ESR;
    return EvaluateStmt(Result, Info, IS->getElse(), Case);
  }

  case Stmt::WhileStmtClass: {
    EvalStmtResult ESR =
        EvaluateLoopBody(Result, Info, cast<WhileStmt>(S)->getBody(), Case);
    if (ESR != ESR_Continue)
      return ESR;
    break;
  }

  case Stmt::ForStmtClass: {
    const ForStmt *FS = cast<ForStmt>(S);
    EvalStmtResult ESR =
        EvaluateLoopBody(Result, Info, FS->getBody(), Case);
    if (ESR != ESR_Continue)
      return ESR;
    if (FS->getInc()) {
      FullExpressionRAII IncScope(Info);
      if (!EvaluateIgnoredValue(Info, FS->getInc()))
        return ESR_Failed;
    }
    break;
  }

  case Stmt::DeclStmtClass:
    // FIXME: If the variable has initialization that can't be jumped over,
    // bail out of any immediately-surrounding compound-statement too.
  default:
    return ESR_CaseNotFound;
  }
}

switch (S->getStmtClass()) {
default:
  if (const Expr *E = dyn_cast<Expr>(S)) {
    // Don't bother evaluating beyond an expression-statement which couldn't
    // be evaluated.
    FullExpressionRAII Scope(Info);
    if (!EvaluateIgnoredValue(Info, E))
      return ESR_Failed;
    return ESR_Succeeded;
  }

  Info.FFDiag(S->getLocStart());
  return ESR_Failed;

case Stmt::NullStmtClass:
  return ESR_Succeeded;

case Stmt::DeclStmtClass: {
  const DeclStmt *DS = cast<DeclStmt>(S);
  for (const auto *DclIt : DS->decls()) {
    // Each declaration initialization is its own full-expression.
    // FIXME: This isn't quite right; if we're performing aggregate
    // initialization, each braced subexpression is its own full-expression.
    FullExpressionRAII Scope(Info);
    if (!EvaluateDecl(Info, DclIt) && !Info.noteFailure())
      return ESR_Failed;
  }
  return ESR_Succeeded;
}

case Stmt::ReturnStmtClass: {
  const Expr *RetExpr = cast<ReturnStmt>(S)->getRetValue();
  FullExpressionRAII Scope(Info);
  if (RetExpr &&
      !(Result.Slot
            ? EvaluateInPlace(Result.Value, Info, *Result.Slot, RetExpr)
            : Evaluate(Result.Value, Info, RetExpr)))
    return ESR_Failed;
  return ESR_Returned;
}

case Stmt::CompoundStmtClass: {
  BlockScopeRAII Scope(Info);

  const CompoundStmt *CS = cast<CompoundStmt>(S);
  for (const auto *BI : CS->body()) {
    EvalStmtResult ESR = EvaluateStmt(Result, Info, BI, Case);
    if (ESR == ESR_Succeeded)
      Case = nullptr;
    else if (ESR != ESR_CaseNotFound)
      return ESR;
  }
  return Case ? ESR_CaseNotFound : ESR_Succeeded;
}

case Stmt::IfStmtClass: {
  const IfStmt *IS = cast<IfStmt>(S);

  // Evaluate the condition, as either a var decl or as an expression.
  BlockScopeRAII Scope(Info);
  if (const Stmt *Init = IS->getInit()) {
    EvalStmtResult ESR = EvaluateStmt(Result, Info, Init);
    if (ESR != ESR_Succeeded)
      return ESR;
  }
  bool Cond;
  if (!EvaluateCond(Info, IS->getConditionVariable(), IS->getCond(), Cond))
    return ESR_Failed;

  if (const Stmt *SubStmt = Cond ? IS->getThen() : IS->getElse()) {
    EvalStmtResult ESR = EvaluateStmt(Result, Info, SubStmt);
    if (ESR != ESR_Succeeded)
      return ESR;
  }
  return ESR_Succeeded;
}

case Stmt::WhileStmtClass: {
  const WhileStmt *WS = cast<WhileStmt>(S);
  while (true) {
    BlockScopeRAII Scope(Info);
    bool Continue;
    if (!EvaluateCond(Info, WS->getConditionVariable(), WS->getCond(),
                      Continue))
      return ESR_Failed;
    if (!Continue)
      break;

    EvalStmtResult ESR = EvaluateLoopBody(Result, Info, WS->getBody());
    if (ESR != ESR_Continue)
      return ESR;
  }
  return ESR_Succeeded;
}

case Stmt::DoStmtClass: {
  const DoStmt *DS = cast<DoStmt>(S);
  bool Continue;
  do {
    EvalStmtResult ESR = EvaluateLoopBody(Result, Info, DS->getBody(), Case);
    if (ESR != ESR_Continue)
      return ESR;
    Case = nullptr;

    FullExpressionRAII CondScope(Info);
    if (!EvaluateAsBooleanCondition(DS->getCond(), Continue, Info))
      return ESR_Failed;
  } while (Continue);
  return ESR_Succeeded;
}

case Stmt::ForStmtClass: {
  const ForStmt *FS = cast<ForStmt>(S);
  BlockScopeRAII Scope(Info);
  if (FS->getInit()) {
    EvalStmtResult ESR = EvaluateStmt(Result, Info, FS->getInit());
    if (ESR != ESR_Succeeded)
      return ESR;
  }
  while (true) {
    BlockScopeRAII Scope(Info);
    bool Continue = true;
    if (FS->getCond() && !EvaluateCond(Info, FS->getConditionVariable(),
                                       FS->getCond(), Continue))
      return ESR_Failed;
    if (!Continue)
      break;

    EvalStmtResult ESR = EvaluateLoopBody(Result, Info, FS->getBody());
    if (ESR != ESR_Continue)
      return ESR;

    if (FS->getInc()) {
      FullExpressionRAII IncScope(Info);
      if (!EvaluateIgnoredValue(Info, FS->getInc()))
        return ESR_Failed;
    }
  }
  return ESR_Succeeded;
}

case Stmt::CXXForRangeStmtClass: {
  const CXXForRangeStmt *FS = cast<CXXForRangeStmt>(S);
  BlockScopeRAII Scope(Info);

  // Initialize the __range variable.
  EvalStmtResult ESR = EvaluateStmt(Result, Info, FS->getRangeStmt());
  if (ESR != ESR_Succeeded)
    return ESR;

  // Create the __begin and __end iterators.
  ESR = EvaluateStmt(Result, Info, FS->getBeginStmt());
  if (ESR != ESR_Succeeded)
    return ESR;
  ESR = EvaluateStmt(Result, Info, FS->getEndStmt());
  if (ESR != ESR_Succeeded)
    return ESR;

  while (true) {
    // Condition: __begin != __end.
    {
      bool Continue = true;
      FullExpressionRAII CondExpr(Info);
      if (!EvaluateAsBooleanCondition(FS->getCond(), Continue, Info))
        return ESR_Failed;
      if (!Continue)
        break;
    }

    // User's variable declaration, initialized by *__begin.
    BlockScopeRAII InnerScope(Info);
    ESR = EvaluateStmt(Result, Info, FS->getLoopVarStmt());
    if (ESR != ESR_Succeeded)
      return ESR;

    // Loop body.
    ESR = EvaluateLoopBody(Result, Info, FS->getBody());
    if (ESR != ESR_Continue)
      return ESR;

    // Increment: ++__begin
    if (!EvaluateIgnoredValue(Info, FS->getInc()))
      return ESR_Failed;
  }

  return ESR_Succeeded;
}

case Stmt::SwitchStmtClass:
  return EvaluateSwitch(Result, Info, cast<SwitchStmt>(S));

case Stmt::ContinueStmtClass:
  return ESR_Continue;

case Stmt::BreakStmtClass:
  return ESR_Break;

case Stmt::LabelStmtClass:
  return EvaluateStmt(Result, Info, cast<LabelStmt>(S)->getSubStmt(), Case);

case Stmt::AttributedStmtClass:
  // As a general principle, C++11 attributes can be ignored without
  // any semantic impact.
  return EvaluateStmt(Result, Info, cast<AttributedStmt>(S)->getSubStmt(),
                      Case);

case Stmt::CaseStmtClass:
case Stmt::DefaultStmtClass:
  return EvaluateStmt(Result, Info, cast<SwitchCase>(S)->getSubStmt(), Case);
}
4145}

4147/// CheckTrivialDefaultConstructor - Check whether a constructor is a trivial
4148/// default constructor. If so, we'll fold it whether or not it's marked as
4149/// constexpr. If it is marked as constexpr, we will never implicitly define it,
4150/// so we need special handling.
4151static bool CheckTrivialDefaultConstructor(EvalInfo &Info, SourceLocation Loc,
                                         const CXXConstructorDecl *CD,
                                         bool IsValueInitialization) {
if (!CD->isTrivial() || !CD->isDefaultConstructor())
  return false;

// Value-initialization does not call a trivial default constructor, so such a
// call is a core constant expression whether or not the constructor is
// constexpr.
if (!CD->isConstexpr() && !IsValueInitialization) {
  if (Info.getLangOpts().CPlusPlus11) {
    // FIXME: If DiagDecl is an implicitly-declared special member function,
    // we should be much more explicit about why it's not constexpr.
    Info.CCEDiag(Loc, diag::note_constexpr_invalid_function, 1)
      << /*IsConstexpr*/0 << /*IsConstructor*/1 << CD;
    Info.Note(CD->getLocation(), diag::note_declared_at);
  } else {
    Info.CCEDiag(Loc, diag::note_invalid_subexpr_in_const_expr);
  }
}
return true;
4172}

4174/// CheckConstexprFunction - Check that a function can be called in a constant
4175/// expression.
4176static bool CheckConstexprFunction(EvalInfo &Info, SourceLocation CallLoc,
                                 const FunctionDecl *Declaration,
                                 const FunctionDecl *Definition,
                                 const Stmt *Body) {
// Potential constant expressions can contain calls to declared, but not yet
// defined, constexpr functions.
if (Info.checkingPotentialConstantExpression() && !Definition &&
    Declaration->isConstexpr())
  return false;

// Bail out with no diagnostic if the function declaration itself is invalid.
// We will have produced a relevant diagnostic while parsing it.
if (Declaration->isInvalidDecl())
  return false;

// Can we evaluate this function call?
if (Definition && Definition->isConstexpr() &&
    !Definition->isInvalidDecl() && Body)
  return true;

if (Info.getLangOpts().CPlusPlus11) {
  const FunctionDecl *DiagDecl = Definition ? Definition : Declaration;
  
  // If this function is not constexpr because it is an inherited
  // non-constexpr constructor, diagnose that directly.
  auto *CD = dyn_cast<CXXConstructorDecl>(DiagDecl);
  if (CD && CD->isInheritingConstructor()) {
    auto *Inherited = CD->getInheritedConstructor().getConstructor();
    if (!Inherited->isConstexpr()) 
      DiagDecl = CD = Inherited;
  }

  // FIXME: If DiagDecl is an implicitly-declared special member function
  // or an inheriting constructor, we should be much more explicit about why
  // it's not constexpr.
  if (CD && CD->isInheritingConstructor())
    Info.FFDiag(CallLoc, diag::note_constexpr_invalid_inhctor, 1)
      << CD->getInheritedConstructor().getConstructor()->getParent();
  else
    Info.FFDiag(CallLoc, diag::note_constexpr_invalid_function, 1)
      << DiagDecl->isConstexpr() << (bool)CD << DiagDecl;
  Info.Note(DiagDecl->getLocation(), diag::note_declared_at);
} else {
  Info.FFDiag(CallLoc, diag::note_invalid_subexpr_in_const_expr);
}
return false;
4222}

4224/// Determine if a class has any fields that might need to be copied by a
4225/// trivial copy or move operation.
4226static bool hasFields(const CXXRecordDecl *RD) {
if (!RD || RD->isEmpty())
  return false;
for (auto *FD : RD->fields()) {
  if (FD->isUnnamedBitfield())
    continue;
  return true;
}
for (auto &Base : RD->bases())
  if (hasFields(Base.getType()->getAsCXXRecordDecl()))
    return true;
return false;
4238}

4240namespace {
4241typedef SmallVector<APValue, 8> ArgVector;
4242}

4244/// EvaluateArgs - Evaluate the arguments to a function call.
4245static bool EvaluateArgs(ArrayRef<const Expr*> Args, ArgVector &ArgValues,
                       EvalInfo &Info) {
bool Success = true;
for (ArrayRef<const Expr*>::iterator I = Args.begin(), E = Args.end();
     I != E; ++I) {
  if (!Evaluate(ArgValues[I - Args.begin()], Info, *I)) {
    // If we're checking for a potential constant expression, evaluate all
    // initializers even if some of them fail.
    if (!Info.noteFailure())
      return false;
    Success = false;
  }
}
return Success;
4259}

4261/// Evaluate a function call.
4262static bool HandleFunctionCall(SourceLocation CallLoc,
                             const FunctionDecl *Callee, const LValue *This,
                             ArrayRef<const Expr*> Args, const Stmt *Body,
                             EvalInfo &Info, APValue &Result,
                             const LValue *ResultSlot) {
ArgVector ArgValues(Args.size());
if (!EvaluateArgs(Args, ArgValues, Info))
  return false;

if (!Info.CheckCallLimit(CallLoc))
  return false;

CallStackFrame Frame(Info, CallLoc, Callee, This, ArgValues.data());

// For a trivial copy or move assignment, perform an APValue copy. This is
// essential for unions, where the operations performed by the assignment
// operator cannot be represented as statements.
//
// Skip this for non-union classes with no fields; in that case, the defaulted
// copy/move does not actually read the object.
const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(Callee);
if (MD && MD->isDefaulted() &&
    (MD->getParent()->isUnion() ||
     (MD->isTrivial() && hasFields(MD->getParent())))) {
  assert(This &&(static_cast <bool> (This && (MD->isCopyAssignmentOperator
() || MD->isMoveAssignmentOperator())) ? void (0) : __assert_fail
 ("This && (MD->isCopyAssignmentOperator() || MD->isMoveAssignmentOperator())"
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 4287, __extension__ __PRETTY_FUNCTION__))
         (MD->isCopyAssignmentOperator() || MD->isMoveAssignmentOperator()))(static_cast <bool> (This && (MD->isCopyAssignmentOperator
() || MD->isMoveAssignmentOperator())) ? void (0) : __assert_fail
 ("This && (MD->isCopyAssignmentOperator() || MD->isMoveAssignmentOperator())"
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 4287, __extension__ __PRETTY_FUNCTION__));
  LValue RHS;
  RHS.setFrom(Info.Ctx, ArgValues[0]);
  APValue RHSValue;
  if (!handleLValueToRValueConversion(Info, Args[0], Args[0]->getType(),
                                      RHS, RHSValue))
    return false;
  if (!handleAssignment(Info, Args[0], *This, MD->getThisType(Info.Ctx),
                        RHSValue))
    return false;
  This->moveInto(Result);
  return true;
} else if (MD && isLambdaCallOperator(MD)) {
  // We're in a lambda; determine the lambda capture field maps.
  MD->getParent()->getCaptureFields(Frame.LambdaCaptureFields,
                                    Frame.LambdaThisCaptureField);
}

StmtResult Ret = {Result, ResultSlot};
EvalStmtResult ESR = EvaluateStmt(Ret, Info, Body);
if (ESR == ESR_Succeeded) {
  if (Callee->getReturnType()->isVoidType())
    return true;
  Info.FFDiag(Callee->getLocEnd(), diag::note_constexpr_no_return);
}
return ESR == ESR_Returned;
4313}

4315/// Evaluate a constructor call.
4316static bool HandleConstructorCall(const Expr *E, const LValue &This,
                                APValue *ArgValues,
                                const CXXConstructorDecl *Definition,
                                EvalInfo &Info, APValue &Result) {
SourceLocation CallLoc = E->getExprLoc();
if (!Info.CheckCallLimit(CallLoc))
  return false;

const CXXRecordDecl *RD = Definition->getParent();
if (RD->getNumVBases()) {
  Info.FFDiag(CallLoc, diag::note_constexpr_virtual_base) << RD;
  return false;
}

EvalInfo::EvaluatingConstructorRAII EvalObj(
    Info, {This.getLValueBase(), This.CallIndex});
CallStackFrame Frame(Info, CallLoc, Definition, &This, ArgValues);

// FIXME: Creating an APValue just to hold a nonexistent return value is
// wasteful.
APValue RetVal;
StmtResult Ret = {RetVal, nullptr};

// If it's a delegating constructor, delegate.
if (Definition->isDelegatingConstructor()) {
  CXXConstructorDecl::init_const_iterator I = Definition->init_begin();
  {
    FullExpressionRAII InitScope(Info);
    if (!EvaluateInPlace(Result, Info, This, (*I)->getInit()))
      return false;
  }
  return EvaluateStmt(Ret, Info, Definition->getBody()) != ESR_Failed;
}

// For a trivial copy or move constructor, perform an APValue copy. This is
// essential for unions (or classes with anonymous union members), where the
// operations performed by the constructor cannot be represented by
// ctor-initializers.
//
// Skip this for empty non-union classes; we should not perform an
// lvalue-to-rvalue conversion on them because their copy constructor does not
// actually read them.
if (Definition->isDefaulted() && Definition->isCopyOrMoveConstructor() &&
    (Definition->getParent()->isUnion() ||
     (Definition->isTrivial() && hasFields(Definition->getParent())))) {
  LValue RHS;
  RHS.setFrom(Info.Ctx, ArgValues[0]);
  return handleLValueToRValueConversion(
      Info, E, Definition->getParamDecl(0)->getType().getNonReferenceType(),
      RHS, Result);
}

// Reserve space for the struct members.
if (!RD->isUnion() && Result.isUninit())
  Result = APValue(APValue::UninitStruct(), RD->getNumBases(),
                   std::distance(RD->field_begin(), RD->field_end()));

if (RD->isInvalidDecl()) return false;
const ASTRecordLayout &Layout = Info.Ctx.getASTRecordLayout(RD);

// A scope for temporaries lifetime-extended by reference members.
BlockScopeRAII LifetimeExtendedScope(Info);

bool Success = true;
unsigned BasesSeen = 0;
4381#ifndef NDEBUG
CXXRecordDecl::base_class_const_iterator BaseIt = RD->bases_begin();
4383#endif
for (const auto *I : Definition->inits()) {
  LValue Subobject = This;
  LValue SubobjectParent = This;
  APValue *Value = &Result;

  // Determine the subobject to initialize.
  FieldDecl *FD = nullptr;
  if (I->isBaseInitializer()) {
    QualType BaseType(I->getBaseClass(), 0);
4393#ifndef NDEBUG
    // Non-virtual base classes are initialized in the order in the class
    // definition. We have already checked for virtual base classes.
    assert(!BaseIt->isVirtual() && "virtual base for literal type")(static_cast <bool> (!BaseIt->isVirtual() &&
 "virtual base for literal type") ? void (0) : __assert_fail (
"!BaseIt->isVirtual() && \"virtual base for literal type\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 4396, __extension__ __PRETTY_FUNCTION__));
    assert(Info.Ctx.hasSameType(BaseIt->getType(), BaseType) &&(static_cast <bool> (Info.Ctx.hasSameType(BaseIt->getType
(), BaseType) && "base class initializers not in expected order"
) ? void (0) : __assert_fail ("Info.Ctx.hasSameType(BaseIt->getType(), BaseType) && \"base class initializers not in expected order\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 4398, __extension__ __PRETTY_FUNCTION__))
           "base class initializers not in expected order")(static_cast <bool> (Info.Ctx.hasSameType(BaseIt->getType
(), BaseType) && "base class initializers not in expected order"
) ? void (0) : __assert_fail ("Info.Ctx.hasSameType(BaseIt->getType(), BaseType) && \"base class initializers not in expected order\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 4398, __extension__ __PRETTY_FUNCTION__));
    ++BaseIt;
4400#endif
    if (!HandleLValueDirectBase(Info, I->getInit(), Subobject, RD,
                                BaseType->getAsCXXRecordDecl(), &Layout))
      return false;
    Value = &Result.getStructBase(BasesSeen++);
  } else if ((FD = I->getMember())) {
    if (!HandleLValueMember(Info, I->getInit(), Subobject, FD, &Layout))
      return false;
    if (RD->isUnion()) {
      Result = APValue(FD);
      Value = &Result.getUnionValue();
    } else {
      Value = &Result.getStructField(FD->getFieldIndex());
    }
  } else if (IndirectFieldDecl *IFD = I->getIndirectMember()) {
    // Walk the indirect field decl's chain to find the object to initialize,
    // and make sure we've initialized every step along it.
    auto IndirectFieldChain = IFD->chain();
    for (auto *C : IndirectFieldChain) {
      FD = cast<FieldDecl>(C);
      CXXRecordDecl *CD = cast<CXXRecordDecl>(FD->getParent());
      // Switch the union field if it differs. This happens if we had
      // preceding zero-initialization, and we're now initializing a union
      // subobject other than the first.
      // FIXME: In this case, the values of the other subobjects are
      // specified, since zero-initialization sets all padding bits to zero.
      if (Value->isUninit() ||
          (Value->isUnion() && Value->getUnionField() != FD)) {
        if (CD->isUnion())
          *Value = APValue(FD);
        else
          *Value = APValue(APValue::UninitStruct(), CD->getNumBases(),
                           std::distance(CD->field_begin(), CD->field_end()));
      }
      // Store Subobject as its parent before updating it for the last element
      // in the chain.
      if (C == IndirectFieldChain.back())
        SubobjectParent = Subobject;
      if (!HandleLValueMember(Info, I->getInit(), Subobject, FD))
        return false;
      if (CD->isUnion())
        Value = &Value->getUnionValue();
      else
        Value = &Value->getStructField(FD->getFieldIndex());
    }
  } else {
    llvm_unreachable("unknown base initializer kind")::llvm::llvm_unreachable_internal("unknown base initializer kind"
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 4446);
  }

  // Need to override This for implicit field initializers as in this case
  // This refers to innermost anonymous struct/union containing initializer,
  // not to currently constructed class.
  const Expr *Init = I->getInit();
  ThisOverrideRAII ThisOverride(*Info.CurrentCall, &SubobjectParent,
                                isa<CXXDefaultInitExpr>(Init));
  FullExpressionRAII InitScope(Info);
  if (!EvaluateInPlace(*Value, Info, Subobject, Init) ||
      (FD && FD->isBitField() &&
       !truncateBitfieldValue(Info, Init, *Value, FD))) {
    // If we're checking for a potential constant expression, evaluate all
    // initializers even if some of them fail.
    if (!Info.noteFailure())
      return false;
    Success = false;
  }
}

return Success &&
       EvaluateStmt(Ret, Info, Definition->getBody()) != ESR_Failed;
4469}

4471static bool HandleConstructorCall(const Expr *E, const LValue &This,
                                ArrayRef<const Expr*> Args,
                                const CXXConstructorDecl *Definition,
                                EvalInfo &Info, APValue &Result) {
ArgVector ArgValues(Args.size());
if (!EvaluateArgs(Args, ArgValues, Info))
  return false;

return HandleConstructorCall(E, This, ArgValues.data(), Definition,
                             Info, Result);
4481}

4483//===----------------------------------------------------------------------===//
4484// Generic Evaluation
4485//===----------------------------------------------------------------------===//
4486namespace {

4488template <class Derived>
4489class ExprEvaluatorBase
: public ConstStmtVisitor<Derived, bool> {
4491private:
Derived &getDerived() { return static_cast<Derived&>(*this); }
bool DerivedSuccess(const APValue &V, const Expr *E) {
  return getDerived().Success(V, E);
}
bool DerivedZeroInitialization(const Expr *E) {
  return getDerived().ZeroInitialization(E);
}

// Check whether a conditional operator with a non-constant condition is a
// potential constant expression. If neither arm is a potential constant
// expression, then the conditional operator is not either.
template<typename ConditionalOperator>
void CheckPotentialConstantConditional(const ConditionalOperator *E) {
  assert(Info.checkingPotentialConstantExpression())(static_cast <bool> (Info.checkingPotentialConstantExpression
()) ? void (0) : __assert_fail ("Info.checkingPotentialConstantExpression()"
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 4505, __extension__ __PRETTY_FUNCTION__));

  // Speculatively evaluate both arms.
  SmallVector<PartialDiagnosticAt, 8> Diag;
  {
    SpeculativeEvaluationRAII Speculate(Info, &Diag);
    StmtVisitorTy::Visit(E->getFalseExpr());
    if (Diag.empty())
      return;
  }

  {
    SpeculativeEvaluationRAII Speculate(Info, &Diag);
    Diag.clear();
    StmtVisitorTy::Visit(E->getTrueExpr());
    if (Diag.empty())
      return;
  }

  Error(E, diag::note_constexpr_conditional_never_const);
}


template<typename ConditionalOperator>
bool HandleConditionalOperator(const ConditionalOperator *E) {
  bool BoolResult;
  if (!EvaluateAsBooleanCondition(E->getCond(), BoolResult, Info)) {
    if (Info.checkingPotentialConstantExpression() && Info.noteFailure()) {
      CheckPotentialConstantConditional(E);
      return false;
    }
    if (Info.noteFailure()) {
      StmtVisitorTy::Visit(E->getTrueExpr());
      StmtVisitorTy::Visit(E->getFalseExpr());
    }
    return false;
  }

  Expr *EvalExpr = BoolResult ? E->getTrueExpr() : E->getFalseExpr();
  return StmtVisitorTy::Visit(EvalExpr);
}

4547protected:
EvalInfo &Info;
typedef ConstStmtVisitor<Derived, bool> StmtVisitorTy;
typedef ExprEvaluatorBase ExprEvaluatorBaseTy;

OptionalDiagnostic CCEDiag(const Expr *E, diag::kind D) {
  return Info.CCEDiag(E, D);
}

bool ZeroInitialization(const Expr *E) { return Error(E); }

4558public:
ExprEvaluatorBase(EvalInfo &Info) : Info(Info) {}

EvalInfo &getEvalInfo() { return Info; }

/// Report an evaluation error. This should only be called when an error is
/// first discovered. When propagating an error, just return false.
bool Error(const Expr *E, diag::kind D) {
  Info.FFDiag(E, D);
  return false;
}
bool Error(const Expr *E) {
  return Error(E, diag::note_invalid_subexpr_in_const_expr);
}

bool VisitStmt(const Stmt *) {
  llvm_unreachable("Expression evaluator should not be called on stmts")::llvm::llvm_unreachable_internal("Expression evaluator should not be called on stmts"
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 4574);
}
bool VisitExpr(const Expr *E) {
  return Error(E);
}

bool VisitParenExpr(const ParenExpr *E)
  { return StmtVisitorTy::Visit(E->getSubExpr()); }
bool VisitUnaryExtension(const UnaryOperator *E)
  { return StmtVisitorTy::Visit(E->getSubExpr()); }
bool VisitUnaryPlus(const UnaryOperator *E)
  { return StmtVisitorTy::Visit(E->getSubExpr()); }
bool VisitChooseExpr(const ChooseExpr *E)
  { return StmtVisitorTy::Visit(E->getChosenSubExpr()); }
bool VisitGenericSelectionExpr(const GenericSelectionExpr *E)
  { return StmtVisitorTy::Visit(E->getResultExpr()); }
bool VisitSubstNonTypeTemplateParmExpr(const SubstNonTypeTemplateParmExpr *E)
  { return StmtVisitorTy::Visit(E->getReplacement()); }
bool VisitCXXDefaultArgExpr(const CXXDefaultArgExpr *E)
  { return StmtVisitorTy::Visit(E->getExpr()); }
bool VisitCXXDefaultInitExpr(const CXXDefaultInitExpr *E) {
  // The initializer may not have been parsed yet, or might be erroneous.
  if (!E->getExpr())
    return Error(E);
  return StmtVisitorTy::Visit(E->getExpr());
}
// We cannot create any objects for which cleanups are required, so there is
// nothing to do here; all cleanups must come from unevaluated subexpressions.
bool VisitExprWithCleanups(const ExprWithCleanups *E)
  { return StmtVisitorTy::Visit(E->getSubExpr()); }

bool VisitCXXReinterpretCastExpr(const CXXReinterpretCastExpr *E) {
  CCEDiag(E, diag::note_constexpr_invalid_cast) << 0;
  return static_cast<Derived*>(this)->VisitCastExpr(E);
}
bool VisitCXXDynamicCastExpr(const CXXDynamicCastExpr *E) {
  CCEDiag(E, diag::note_constexpr_invalid_cast) << 1;
  return static_cast<Derived*>(this)->VisitCastExpr(E);
}

bool VisitBinaryOperator(const BinaryOperator *E) {
  switch (E->getOpcode()) {
  default:
    return Error(E);

  case BO_Comma:
    VisitIgnoredValue(E->getLHS());
    return StmtVisitorTy::Visit(E->getRHS());

  case BO_PtrMemD:
  case BO_PtrMemI: {
    LValue Obj;
    if (!HandleMemberPointerAccess(Info, E, Obj))
      return false;
    APValue Result;
    if (!handleLValueToRValueConversion(Info, E, E->getType(), Obj, Result))
      return false;
    return DerivedSuccess(Result, E);
  }
  }
}

bool VisitBinaryConditionalOperator(const BinaryConditionalOperator *E) {
  // Evaluate and cache the common expression. We treat it as a temporary,
  // even though it's not quite the same thing.
  if (!Evaluate(Info.CurrentCall->createTemporary(E->getOpaqueValue(), false),
                Info, E->getCommon()))
    return false;

  return HandleConditionalOperator(E);
}

bool VisitConditionalOperator(const ConditionalOperator *E) {
  bool IsBcpCall = false;
  // If the condition (ignoring parens) is a __builtin_constant_p call,
  // the result is a constant expression if it can be folded without
  // side-effects. This is an important GNU extension. See GCC PR38377
  // for discussion.
  if (const CallExpr *CallCE =
        dyn_cast<CallExpr>(E->getCond()->IgnoreParenCasts()))
    if (CallCE->getBuiltinCallee() == Builtin::BI__builtin_constant_p)
      IsBcpCall = true;

  // Always assume __builtin_constant_p(...) ? ... : ... is a potential
  // constant expression; we can't check whether it's potentially foldable.
  if (Info.checkingPotentialConstantExpression() && IsBcpCall)
    return false;

  FoldConstant Fold(Info, IsBcpCall);
  if (!HandleConditionalOperator(E)) {
    Fold.keepDiagnostics();
    return false;
  }

  return true;
}

bool VisitOpaqueValueExpr(const OpaqueValueExpr *E) {
  if (APValue *Value = Info.CurrentCall->getTemporary(E))
    return DerivedSuccess(*Value, E);

  const Expr *Source = E->getSourceExpr();
  if (!Source)
    return Error(E);
  if (Source == E) { // sanity checking.
    assert(0 && "OpaqueValueExpr recursively refers to itself")(static_cast <bool> (0 && "OpaqueValueExpr recursively refers to itself"
) ? void (0) : __assert_fail ("0 && \"OpaqueValueExpr recursively refers to itself\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 4679, __extension__ __PRETTY_FUNCTION__));
    return Error(E);
  }
  return StmtVisitorTy::Visit(Source);
}

bool VisitCallExpr(const CallExpr *E) {
  APValue Result;
  if (!handleCallExpr(E, Result, nullptr))
    return false;
  return DerivedSuccess(Result, E);
}

bool handleCallExpr(const CallExpr *E, APValue &Result,
                   const LValue *ResultSlot) {
  const Expr *Callee = E->getCallee()->IgnoreParens();
  QualType CalleeType = Callee->getType();

  const FunctionDecl *FD = nullptr;
  LValue *This = nullptr, ThisVal;
  auto Args = llvm::makeArrayRef(E->getArgs(), E->getNumArgs());
  bool HasQualifier = false;

  // Extract function decl and 'this' pointer from the callee.
  if (CalleeType->isSpecificBuiltinType(BuiltinType::BoundMember)) {
    const ValueDecl *Member = nullptr;
    if (const MemberExpr *ME = dyn_cast<MemberExpr>(Callee)) {
      // Explicit bound member calls, such as x.f() or p->g();
      if (!EvaluateObjectArgument(Info, ME->getBase(), ThisVal))
        return false;
      Member = ME->getMemberDecl();
      This = &ThisVal;
      HasQualifier = ME->hasQualifier();
    } else if (const BinaryOperator *BE = dyn_cast<BinaryOperator>(Callee)) {
      // Indirect bound member calls ('.*' or '->*').
      Member = HandleMemberPointerAccess(Info, BE, ThisVal, false);
      if (!Member) return false;
      This = &ThisVal;
    } else
      return Error(Callee);

    FD = dyn_cast<FunctionDecl>(Member);
    if (!FD)
      return Error(Callee);
  } else if (CalleeType->isFunctionPointerType()) {
    LValue Call;
    if (!EvaluatePointer(Callee, Call, Info))
      return false;

    if (!Call.getLValueOffset().isZero())
      return Error(Callee);
    FD = dyn_cast_or_null<FunctionDecl>(
                           Call.getLValueBase().dyn_cast<const ValueDecl*>());
    if (!FD)
      return Error(Callee);
    // Don't call function pointers which have been cast to some other type.
    // Per DR (no number yet), the caller and callee can differ in noexcept.
    if (!Info.Ctx.hasSameFunctionTypeIgnoringExceptionSpec(
      CalleeType->getPointeeType(), FD->getType())) {
      return Error(E);
    }

    // Overloaded operator calls to member functions are represented as normal
    // calls with '*this' as the first argument.
    const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD);
    if (MD && !MD->isStatic()) {
      // FIXME: When selecting an implicit conversion for an overloaded
      // operator delete, we sometimes try to evaluate calls to conversion
      // operators without a 'this' parameter!
      if (Args.empty())
        return Error(E);

      if (!EvaluateObjectArgument(Info, Args[0], ThisVal))
        return false;
      This = &ThisVal;
      Args = Args.slice(1);
    } else if (MD && MD->isLambdaStaticInvoker()) {   
      // Map the static invoker for the lambda back to the call operator.
      // Conveniently, we don't have to slice out the 'this' argument (as is
      // being done for the non-static case), since a static member function
      // doesn't have an implicit argument passed in.
      const CXXRecordDecl *ClosureClass = MD->getParent();
      assert((static_cast <bool> (ClosureClass->captures_begin() ==
 ClosureClass->captures_end() && "Number of captures must be zero for conversion to function-ptr"
) ? void (0) : __assert_fail ("ClosureClass->captures_begin() == ClosureClass->captures_end() && \"Number of captures must be zero for conversion to function-ptr\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 4763, __extension__ __PRETTY_FUNCTION__))
          ClosureClass->captures_begin() == ClosureClass->captures_end() &&(static_cast <bool> (ClosureClass->captures_begin() ==
 ClosureClass->captures_end() && "Number of captures must be zero for conversion to function-ptr"
) ? void (0) : __assert_fail ("ClosureClass->captures_begin() == ClosureClass->captures_end() && \"Number of captures must be zero for conversion to function-ptr\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 4763, __extension__ __PRETTY_FUNCTION__))
          "Number of captures must be zero for conversion to function-ptr")(static_cast <bool> (ClosureClass->captures_begin() ==
 ClosureClass->captures_end() && "Number of captures must be zero for conversion to function-ptr"
) ? void (0) : __assert_fail ("ClosureClass->captures_begin() == ClosureClass->captures_end() && \"Number of captures must be zero for conversion to function-ptr\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 4763, __extension__ __PRETTY_FUNCTION__));

      const CXXMethodDecl *LambdaCallOp =
          ClosureClass->getLambdaCallOperator();

      // Set 'FD', the function that will be called below, to the call
      // operator.  If the closure object represents a generic lambda, find
      // the corresponding specialization of the call operator.

      if (ClosureClass->isGenericLambda()) {
        assert(MD->isFunctionTemplateSpecialization() &&(static_cast <bool> (MD->isFunctionTemplateSpecialization
() && "A generic lambda's static-invoker function must be a "
 "template specialization") ? void (0) : __assert_fail ("MD->isFunctionTemplateSpecialization() && \"A generic lambda's static-invoker function must be a \" \"template specialization\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 4775, __extension__ __PRETTY_FUNCTION__))
               "A generic lambda's static-invoker function must be a "(static_cast <bool> (MD->isFunctionTemplateSpecialization
() && "A generic lambda's static-invoker function must be a "
 "template specialization") ? void (0) : __assert_fail ("MD->isFunctionTemplateSpecialization() && \"A generic lambda's static-invoker function must be a \" \"template specialization\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 4775, __extension__ __PRETTY_FUNCTION__))
               "template specialization")(static_cast <bool> (MD->isFunctionTemplateSpecialization
() && "A generic lambda's static-invoker function must be a "
 "template specialization") ? void (0) : __assert_fail ("MD->isFunctionTemplateSpecialization() && \"A generic lambda's static-invoker function must be a \" \"template specialization\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 4775, __extension__ __PRETTY_FUNCTION__));
        const TemplateArgumentList *TAL = MD->getTemplateSpecializationArgs();
        FunctionTemplateDecl *CallOpTemplate =
            LambdaCallOp->getDescribedFunctionTemplate();
        void *InsertPos = nullptr;
        FunctionDecl *CorrespondingCallOpSpecialization =
            CallOpTemplate->findSpecialization(TAL->asArray(), InsertPos);
        assert(CorrespondingCallOpSpecialization &&(static_cast <bool> (CorrespondingCallOpSpecialization &&
 "We must always have a function call operator specialization "
 "that corresponds to our static invoker specialization") ? void
 (0) : __assert_fail ("CorrespondingCallOpSpecialization && \"We must always have a function call operator specialization \" \"that corresponds to our static invoker specialization\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 4784, __extension__ __PRETTY_FUNCTION__))
               "We must always have a function call operator specialization "(static_cast <bool> (CorrespondingCallOpSpecialization &&
 "We must always have a function call operator specialization "
 "that corresponds to our static invoker specialization") ? void
 (0) : __assert_fail ("CorrespondingCallOpSpecialization && \"We must always have a function call operator specialization \" \"that corresponds to our static invoker specialization\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 4784, __extension__ __PRETTY_FUNCTION__))
               "that corresponds to our static invoker specialization")(static_cast <bool> (CorrespondingCallOpSpecialization &&
 "We must always have a function call operator specialization "
 "that corresponds to our static invoker specialization") ? void
 (0) : __assert_fail ("CorrespondingCallOpSpecialization && \"We must always have a function call operator specialization \" \"that corresponds to our static invoker specialization\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 4784, __extension__ __PRETTY_FUNCTION__));
        FD = cast<CXXMethodDecl>(CorrespondingCallOpSpecialization);
      } else
        FD = LambdaCallOp;
    }

    
  } else
    return Error(E);

  if (This && !This->checkSubobject(Info, E, CSK_This))
    return false;

  // DR1358 allows virtual constexpr functions in some cases. Don't allow
  // calls to such functions in constant expressions.
  if (This && !HasQualifier &&
      isa<CXXMethodDecl>(FD) && cast<CXXMethodDecl>(FD)->isVirtual())
    return Error(E, diag::note_constexpr_virtual_call);

  const FunctionDecl *Definition = nullptr;
  Stmt *Body = FD->getBody(Definition);

  if (!CheckConstexprFunction(Info, E->getExprLoc(), FD, Definition, Body) ||
      !HandleFunctionCall(E->getExprLoc(), Definition, This, Args, Body, Info,
                          Result, ResultSlot))
    return false;

  return true;
}

bool VisitCompoundLiteralExpr(const CompoundLiteralExpr *E) {
  return StmtVisitorTy::Visit(E->getInitializer());
}
bool VisitInitListExpr(const InitListExpr *E) {
  if (E->getNumInits() == 0)
    return DerivedZeroInitialization(E);
  if (E->getNumInits() == 1)
    return StmtVisitorTy::Visit(E->getInit(0));
  return Error(E);
}
bool VisitImplicitValueInitExpr(const ImplicitValueInitExpr *E) {
  return DerivedZeroInitialization(E);
}
bool VisitCXXScalarValueInitExpr(const CXXScalarValueInitExpr *E) {
  return DerivedZeroInitialization(E);
}
bool VisitCXXNullPtrLiteralExpr(const CXXNullPtrLiteralExpr *E) {
  return DerivedZeroInitialization(E);
}

/// A member expression where the object is a prvalue is itself a prvalue.
bool VisitMemberExpr(const MemberExpr *E) {
  assert(!E->isArrow() && "missing call to bound member function?")(static_cast <bool> (!E->isArrow() && "missing call to bound member function?"
) ? void (0) : __assert_fail ("!E->isArrow() && \"missing call to bound member function?\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 4836, __extension__ __PRETTY_FUNCTION__));

  APValue Val;
  if (!Evaluate(Val, Info, E->getBase()))
    return false;

  QualType BaseTy = E->getBase()->getType();

  const FieldDecl *FD = dyn_cast<FieldDecl>(E->getMemberDecl());
  if (!FD) return Error(E);
  assert(!FD->getType()->isReferenceType() && "prvalue reference?")(static_cast <bool> (!FD->getType()->isReferenceType
() && "prvalue reference?") ? void (0) : __assert_fail
 ("!FD->getType()->isReferenceType() && \"prvalue reference?\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 4846, __extension__ __PRETTY_FUNCTION__));
  assert(BaseTy->castAs<RecordType>()->getDecl()->getCanonicalDecl() ==(static_cast <bool> (BaseTy->castAs<RecordType>
()->getDecl()->getCanonicalDecl() == FD->getParent()
->getCanonicalDecl() && "record / field mismatch")
 ? void (0) : __assert_fail ("BaseTy->castAs<RecordType>()->getDecl()->getCanonicalDecl() == FD->getParent()->getCanonicalDecl() && \"record / field mismatch\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 4848, __extension__ __PRETTY_FUNCTION__))
         FD->getParent()->getCanonicalDecl() && "record / field mismatch")(static_cast <bool> (BaseTy->castAs<RecordType>
()->getDecl()->getCanonicalDecl() == FD->getParent()
->getCanonicalDecl() && "record / field mismatch")
 ? void (0) : __assert_fail ("BaseTy->castAs<RecordType>()->getDecl()->getCanonicalDecl() == FD->getParent()->getCanonicalDecl() && \"record / field mismatch\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 4848, __extension__ __PRETTY_FUNCTION__));

  CompleteObject Obj(&Val, BaseTy, true);
  SubobjectDesignator Designator(BaseTy);
  Designator.addDeclUnchecked(FD);

  APValue Result;
  return extractSubobject(Info, E, Obj, Designator, Result) &&
         DerivedSuccess(Result, E);
}

bool VisitCastExpr(const CastExpr *E) {
  switch (E->getCastKind()) {
  default:
    break;

  case CK_AtomicToNonAtomic: {
    APValue AtomicVal;
    // This does not need to be done in place even for class/array types:
    // atomic-to-non-atomic conversion implies copying the object
    // representation.
    if (!Evaluate(AtomicVal, Info, E->getSubExpr()))
      return false;
    return DerivedSuccess(AtomicVal, E);
  }

  case CK_NoOp:
  case CK_UserDefinedConversion:
    return StmtVisitorTy::Visit(E->getSubExpr());

  case CK_LValueToRValue: {
    LValue LVal;
    if (!EvaluateLValue(E->getSubExpr(), LVal, Info))
      return false;
    APValue RVal;
    // Note, we use the subexpression's type in order to retain cv-qualifiers.
    if (!handleLValueToRValueConversion(Info, E, E->getSubExpr()->getType(),
                                        LVal, RVal))
      return false;
    return DerivedSuccess(RVal, E);
  }
  }

  return Error(E);
}

bool VisitUnaryPostInc(const UnaryOperator *UO) {
  return VisitUnaryPostIncDec(UO);
}
bool VisitUnaryPostDec(const UnaryOperator *UO) {
  return VisitUnaryPostIncDec(UO);
}
bool VisitUnaryPostIncDec(const UnaryOperator *UO) {
  if (!Info.getLangOpts().CPlusPlus14 && !Info.keepEvaluatingAfterFailure())
    return Error(UO);

  LValue LVal;
  if (!EvaluateLValue(UO->getSubExpr(), LVal, Info))
    return false;
  APValue RVal;
  if (!handleIncDec(this->Info, UO, LVal, UO->getSubExpr()->getType(),
                    UO->isIncrementOp(), &RVal))
    return false;
  return DerivedSuccess(RVal, UO);
}

bool VisitStmtExpr(const StmtExpr *E) {
  // We will have checked the full-expressions inside the statement expression
  // when they were completed, and don't need to check them again now.
  if (Info.checkingForOverflow())
    return Error(E);

  BlockScopeRAII Scope(Info);
  const CompoundStmt *CS = E->getSubStmt();
  if (CS->body_empty())
    return true;

  for (CompoundStmt::const_body_iterator BI = CS->body_begin(),
                                         BE = CS->body_end();
       /**/; ++BI) {
    if (BI + 1 == BE) {
      const Expr *FinalExpr = dyn_cast<Expr>(*BI);
      if (!FinalExpr) {
        Info.FFDiag((*BI)->getLocStart(),
                  diag::note_constexpr_stmt_expr_unsupported);
        return false;
      }
      return this->Visit(FinalExpr);
    }

    APValue ReturnValue;
    StmtResult Result = { ReturnValue, nullptr };
    EvalStmtResult ESR = EvaluateStmt(Result, Info, *BI);
    if (ESR != ESR_Succeeded) {
      // FIXME: If the statement-expression terminated due to 'return',
      // 'break', or 'continue', it would be nice to propagate that to
      // the outer statement evaluation rather than bailing out.
      if (ESR != ESR_Failed)
        Info.FFDiag((*BI)->getLocStart(),
                  diag::note_constexpr_stmt_expr_unsupported);
      return false;
    }
  }

  llvm_unreachable("Return from function from the loop above.")::llvm::llvm_unreachable_internal("Return from function from the loop above."
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 4952);
}

/// Visit a value which is evaluated, but whose value is ignored.
void VisitIgnoredValue(const Expr *E) {
  EvaluateIgnoredValue(Info, E);
}

/// Potentially visit a MemberExpr's base expression.
void VisitIgnoredBaseExpression(const Expr *E) {
  // While MSVC doesn't evaluate the base expression, it does diagnose the
  // presence of side-effecting behavior.
  if (Info.getLangOpts().MSVCCompat && !E->HasSideEffects(Info.Ctx))
    return;
  VisitIgnoredValue(E);
}
4968};

4970}

4972//===----------------------------------------------------------------------===//
4973// Common base class for lvalue and temporary evaluation.
4974//===----------------------------------------------------------------------===//
4975namespace {
4976template<class Derived>
4977class LValueExprEvaluatorBase
: public ExprEvaluatorBase<Derived> {
4979protected:
LValue &Result;
bool InvalidBaseOK;
typedef LValueExprEvaluatorBase LValueExprEvaluatorBaseTy;
typedef ExprEvaluatorBase<Derived> ExprEvaluatorBaseTy;

bool Success(APValue::LValueBase B) {
  Result.set(B);
  return true;
}

bool evaluatePointer(const Expr *E, LValue &Result) {
  return EvaluatePointer(E, Result, this->Info, InvalidBaseOK);
}

4994public:
LValueExprEvaluatorBase(EvalInfo &Info, LValue &Result, bool InvalidBaseOK)
    : ExprEvaluatorBaseTy(Info), Result(Result),
      InvalidBaseOK(InvalidBaseOK) {}

bool Success(const APValue &V, const Expr *E) {
  Result.setFrom(this->Info.Ctx, V);
  return true;
}

bool VisitMemberExpr(const MemberExpr *E) {
  // Handle non-static data members.
  QualType BaseTy;
  bool EvalOK;
  if (E->isArrow()) {
    EvalOK = evaluatePointer(E->getBase(), Result);
    BaseTy = E->getBase()->getType()->castAs<PointerType>()->getPointeeType();
  } else if (E->getBase()->isRValue()) {
    assert(E->getBase()->getType()->isRecordType())(static_cast <bool> (E->getBase()->getType()->
isRecordType()) ? void (0) : __assert_fail ("E->getBase()->getType()->isRecordType()"
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 5012, __extension__ __PRETTY_FUNCTION__));
    EvalOK = EvaluateTemporary(E->getBase(), Result, this->Info);
    BaseTy = E->getBase()->getType();
  } else {
    EvalOK = this->Visit(E->getBase());
    BaseTy = E->getBase()->getType();
  }
  if (!EvalOK) {
    if (!InvalidBaseOK)
      return false;
    Result.setInvalid(E);
    return true;
  }

  const ValueDecl *MD = E->getMemberDecl();
  if (const FieldDecl *FD = dyn_cast<FieldDecl>(E->getMemberDecl())) {
    assert(BaseTy->getAs<RecordType>()->getDecl()->getCanonicalDecl() ==(static_cast <bool> (BaseTy->getAs<RecordType>
()->getDecl()->getCanonicalDecl() == FD->getParent()
->getCanonicalDecl() && "record / field mismatch")
 ? void (0) : __assert_fail ("BaseTy->getAs<RecordType>()->getDecl()->getCanonicalDecl() == FD->getParent()->getCanonicalDecl() && \"record / field mismatch\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 5029, __extension__ __PRETTY_FUNCTION__))
           FD->getParent()->getCanonicalDecl() && "record / field mismatch")(static_cast <bool> (BaseTy->getAs<RecordType>
()->getDecl()->getCanonicalDecl() == FD->getParent()
->getCanonicalDecl() && "record / field mismatch")
 ? void (0) : __assert_fail ("BaseTy->getAs<RecordType>()->getDecl()->getCanonicalDecl() == FD->getParent()->getCanonicalDecl() && \"record / field mismatch\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 5029, __extension__ __PRETTY_FUNCTION__));
    (void)BaseTy;
    if (!HandleLValueMember(this->Info, E, Result, FD))
      return false;
  } else if (const IndirectFieldDecl *IFD = dyn_cast<IndirectFieldDecl>(MD)) {
    if (!HandleLValueIndirectMember(this->Info, E, Result, IFD))
      return false;
  } else
    return this->Error(E);

  if (MD->getType()->isReferenceType()) {
    APValue RefValue;
    if (!handleLValueToRValueConversion(this->Info, E, MD->getType(), Result,
                                        RefValue))
      return false;
    return Success(RefValue, E);
  }
  return true;
}

bool VisitBinaryOperator(const BinaryOperator *E) {
  switch (E->getOpcode()) {
  default:
    return ExprEvaluatorBaseTy::VisitBinaryOperator(E);

  case BO_PtrMemD:
  case BO_PtrMemI:
    return HandleMemberPointerAccess(this->Info, E, Result);
  }
}

bool VisitCastExpr(const CastExpr *E) {
  switch (E->getCastKind()) {
  default:
    return ExprEvaluatorBaseTy::VisitCastExpr(E);

  case CK_DerivedToBase:
  case CK_UncheckedDerivedToBase:
    if (!this->Visit(E->getSubExpr()))
      return false;

    // Now figure out the necessary offset to add to the base LV to get from
    // the derived class to the base class.
    return HandleLValueBasePath(this->Info, E, E->getSubExpr()->getType(),
                                Result);
  }
}
5076};
5077}

5079//===----------------------------------------------------------------------===//
5080// LValue Evaluation
5081//
5082// This is used for evaluating lvalues (in C and C++), xvalues (in C++11),
5083// function designators (in C), decl references to void objects (in C), and
5084// temporaries (if building with -Wno-address-of-temporary).
5085//
5086// LValue evaluation produces values comprising a base expression of one of the
5087// following types:
5088// - Declarations
5089//  * VarDecl
5090//  * FunctionDecl
5091// - Literals
5092//  * CompoundLiteralExpr in C (and in global scope in C++)
5093//  * StringLiteral
5094//  * CXXTypeidExpr
5095//  * PredefinedExpr
5096//  * ObjCStringLiteralExpr
5097//  * ObjCEncodeExpr
5098//  * AddrLabelExpr
5099//  * BlockExpr
5100//  * CallExpr for a MakeStringConstant builtin
5101// - Locals and temporaries
5102//  * MaterializeTemporaryExpr
5103//  * Any Expr, with a CallIndex indicating the function in which the temporary
5104//    was evaluated, for cases where the MaterializeTemporaryExpr is missing
5105//    from the AST (FIXME).
5106//  * A MaterializeTemporaryExpr that has static storage duration, with no
5107//    CallIndex, for a lifetime-extended temporary.
5108// plus an offset in bytes.
5109//===----------------------------------------------------------------------===//
5110namespace {
5111class LValueExprEvaluator
: public LValueExprEvaluatorBase<LValueExprEvaluator> {
5113public:
LValueExprEvaluator(EvalInfo &Info, LValue &Result, bool InvalidBaseOK) :
  LValueExprEvaluatorBaseTy(Info, Result, InvalidBaseOK) {}

bool VisitVarDecl(const Expr *E, const VarDecl *VD);
bool VisitUnaryPreIncDec(const UnaryOperator *UO);

bool VisitDeclRefExpr(const DeclRefExpr *E);
bool VisitPredefinedExpr(const PredefinedExpr *E) { return Success(E); }
bool VisitMaterializeTemporaryExpr(const MaterializeTemporaryExpr *E);
bool VisitCompoundLiteralExpr(const CompoundLiteralExpr *E);
bool VisitMemberExpr(const MemberExpr *E);
bool VisitStringLiteral(const StringLiteral *E) { return Success(E); }
bool VisitObjCEncodeExpr(const ObjCEncodeExpr *E) { return Success(E); }
bool VisitCXXTypeidExpr(const CXXTypeidExpr *E);
bool VisitCXXUuidofExpr(const CXXUuidofExpr *E);
bool VisitArraySubscriptExpr(const ArraySubscriptExpr *E);
bool VisitUnaryDeref(const UnaryOperator *E);
bool VisitUnaryReal(const UnaryOperator *E);
bool VisitUnaryImag(const UnaryOperator *E);
bool VisitUnaryPreInc(const UnaryOperator *UO) {
  return VisitUnaryPreIncDec(UO);
}
bool VisitUnaryPreDec(const UnaryOperator *UO) {
  return VisitUnaryPreIncDec(UO);
}
bool VisitBinAssign(const BinaryOperator *BO);
bool VisitCompoundAssignOperator(const CompoundAssignOperator *CAO);

bool VisitCastExpr(const CastExpr *E) {
  switch (E->getCastKind()) {
  default:
    return LValueExprEvaluatorBaseTy::VisitCastExpr(E);

  case CK_LValueBitCast:
    this->CCEDiag(E, diag::note_constexpr_invalid_cast) << 2;
    if (!Visit(E->getSubExpr()))
      return false;
    Result.Designator.setInvalid();
    return true;

  case CK_BaseToDerived:
    if (!Visit(E->getSubExpr()))
      return false;
    return HandleBaseToDerivedCast(Info, E, Result);
  }
}
5160};
5161} // end anonymous namespace

5163/// Evaluate an expression as an lvalue. This can be legitimately called on
5164/// expressions which are not glvalues, in three cases:
5165///  * function designators in C, and
5166///  * "extern void" objects
5167///  * @selector() expressions in Objective-C
5168static bool EvaluateLValue(const Expr *E, LValue &Result, EvalInfo &Info,
                         bool InvalidBaseOK) {
assert(E->isGLValue() || E->getType()->isFunctionType() ||(static_cast <bool> (E->isGLValue() || E->getType
()->isFunctionType() || E->getType()->isVoidType() ||
 isa<ObjCSelectorExpr>(E)) ? void (0) : __assert_fail (
"E->isGLValue() || E->getType()->isFunctionType() || E->getType()->isVoidType() || isa<ObjCSelectorExpr>(E)"
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 5171, __extension__ __PRETTY_FUNCTION__))
       E->getType()->isVoidType() || isa<ObjCSelectorExpr>(E))(static_cast <bool> (E->isGLValue() || E->getType
()->isFunctionType() || E->getType()->isVoidType() ||
 isa<ObjCSelectorExpr>(E)) ? void (0) : __assert_fail (
"E->isGLValue() || E->getType()->isFunctionType() || E->getType()->isVoidType() || isa<ObjCSelectorExpr>(E)"
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 5171, __extension__ __PRETTY_FUNCTION__));
return LValueExprEvaluator(Info, Result, InvalidBaseOK).Visit(E);
5173}

5175bool LValueExprEvaluator::VisitDeclRefExpr(const DeclRefExpr *E) {
if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(E->getDecl()))
1
Taking false branch→
  return Success(FD);
if (const VarDecl *VD = dyn_cast<VarDecl>(E->getDecl()))
2
←
Assuming 'VD' is non-null→
3
←
Taking true branch→
  return VisitVarDecl(E, VD);
4
←
Calling 'LValueExprEvaluator::VisitVarDecl'→
if (const BindingDecl *BD = dyn_cast<BindingDecl>(E->getDecl()))
  return Visit(BD->getBinding());
return Error(E);
5183}


5186bool LValueExprEvaluator::VisitVarDecl(const Expr *E, const VarDecl *VD) {

// If we are within a lambda's call operator, check whether the 'VD' referred
// to within 'E' actually represents a lambda-capture that maps to a
// data-member/field within the closure object, and if so, evaluate to the
// field or what the field refers to.
if (Info.CurrentCall && isLambdaCallOperator(Info.CurrentCall->Callee)) {
5
←
Assuming pointer value is null→
  if (auto *FD = Info.CurrentCall->LambdaCaptureFields.lookup(VD)) {
    if (Info.checkingPotentialConstantExpression())
      return false;
    // Start with 'Result' referring to the complete closure object...
    Result = *Info.CurrentCall->This;
    // ... then update it to refer to the field of the closure object
    // that represents the capture.
    if (!HandleLValueMember(Info, E, Result, FD))
      return false;
    // And if the field is of reference type, update 'Result' to refer to what
    // the field refers to.
    if (FD->getType()->isReferenceType()) {
      APValue RVal;
      if (!handleLValueToRValueConversion(Info, E, FD->getType(), Result,
                                          RVal))
        return false;
      Result.setFrom(Info.Ctx, RVal);
    }
    return true;
  }
}
CallStackFrame *Frame = nullptr;
if (VD->hasLocalStorage() && Info.CurrentCall->Index > 1) {
6
←
Access to field 'Index' results in a dereference of a null pointer (loaded from field 'CurrentCall')
  // Only if a local variable was declared in the function currently being
  // evaluated, do we expect to be able to find its value in the current
  // frame. (Otherwise it was likely declared in an enclosing context and
  // could either have a valid evaluatable value (for e.g. a constexpr
  // variable) or be ill-formed (and trigger an appropriate evaluation
  // diagnostic)).
  if (Info.CurrentCall->Callee &&
      Info.CurrentCall->Callee->Equals(VD->getDeclContext())) {
    Frame = Info.CurrentCall;
  }
}

if (!VD->getType()->isReferenceType()) {
  if (Frame) {
    Result.set(VD, Frame->Index);
    return true;
  }
  return Success(VD);
}

APValue *V;
if (!evaluateVarDeclInit(Info, E, VD, Frame, V))
  return false;
if (V->isUninit()) {
  if (!Info.checkingPotentialConstantExpression())
    Info.FFDiag(E, diag::note_constexpr_use_uninit_reference);
  return false;
}
return Success(*V, E);
5245}

5247bool LValueExprEvaluator::VisitMaterializeTemporaryExpr(
  const MaterializeTemporaryExpr *E) {
// Walk through the expression to find the materialized temporary itself.
SmallVector<const Expr *, 2> CommaLHSs;
SmallVector<SubobjectAdjustment, 2> Adjustments;
const Expr *Inner = E->GetTemporaryExpr()->
    skipRValueSubobjectAdjustments(CommaLHSs, Adjustments);

// If we passed any comma operators, evaluate their LHSs.
for (unsigned I = 0, N = CommaLHSs.size(); I != N; ++I)
  if (!EvaluateIgnoredValue(Info, CommaLHSs[I]))
    return false;

// A materialized temporary with static storage duration can appear within the
// result of a constant expression evaluation, so we need to preserve its
// value for use outside this evaluation.
APValue *Value;
if (E->getStorageDuration() == SD_Static) {
  Value = Info.Ctx.getMaterializedTemporaryValue(E, true);
  *Value = APValue();
  Result.set(E);
} else {
  Value = &Info.CurrentCall->
      createTemporary(E, E->getStorageDuration() == SD_Automatic);
  Result.set(E, Info.CurrentCall->Index);
}

QualType Type = Inner->getType();

// Materialize the temporary itself.
if (!EvaluateInPlace(*Value, Info, Result, Inner) ||
    (E->getStorageDuration() == SD_Static &&
     !CheckConstantExpression(Info, E->getExprLoc(), Type, *Value))) {
  *Value = APValue();
  return false;
}

// Adjust our lvalue to refer to the desired subobject.
for (unsigned I = Adjustments.size(); I != 0; /**/) {
  --I;
  switch (Adjustments[I].Kind) {
  case SubobjectAdjustment::DerivedToBaseAdjustment:
    if (!HandleLValueBasePath(Info, Adjustments[I].DerivedToBase.BasePath,
                              Type, Result))
      return false;
    Type = Adjustments[I].DerivedToBase.BasePath->getType();
    break;

  case SubobjectAdjustment::FieldAdjustment:
    if (!HandleLValueMember(Info, E, Result, Adjustments[I].Field))
      return false;
    Type = Adjustments[I].Field->getType();
    break;

  case SubobjectAdjustment::MemberPointerAdjustment:
    if (!HandleMemberPointerAccess(this->Info, Type, Result,
                                   Adjustments[I].Ptr.RHS))
      return false;
    Type = Adjustments[I].Ptr.MPT->getPointeeType();
    break;
  }
}

return true;
5311}

5313bool
5314LValueExprEvaluator::VisitCompoundLiteralExpr(const CompoundLiteralExpr *E) {
assert((!Info.getLangOpts().CPlusPlus || E->isFileScope()) &&(static_cast <bool> ((!Info.getLangOpts().CPlusPlus || E
->isFileScope()) && "lvalue compound literal in c++?"
) ? void (0) : __assert_fail ("(!Info.getLangOpts().CPlusPlus || E->isFileScope()) && \"lvalue compound literal in c++?\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 5316, __extension__ __PRETTY_FUNCTION__))
       "lvalue compound literal in c++?")(static_cast <bool> ((!Info.getLangOpts().CPlusPlus || E
->isFileScope()) && "lvalue compound literal in c++?"
) ? void (0) : __assert_fail ("(!Info.getLangOpts().CPlusPlus || E->isFileScope()) && \"lvalue compound literal in c++?\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 5316, __extension__ __PRETTY_FUNCTION__));
// Defer visiting the literal until the lvalue-to-rvalue conversion. We can
// only see this when folding in C, so there's no standard to follow here.
return Success(E);
5320}

5322bool LValueExprEvaluator::VisitCXXTypeidExpr(const CXXTypeidExpr *E) {
if (!E->isPotentiallyEvaluated())
  return Success(E);

Info.FFDiag(E, diag::note_constexpr_typeid_polymorphic)
  << E->getExprOperand()->getType()
  << E->getExprOperand()->getSourceRange();
return false;
5330}

5332bool LValueExprEvaluator::VisitCXXUuidofExpr(const CXXUuidofExpr *E) {
return Success(E);
5334}

5336bool LValueExprEvaluator::VisitMemberExpr(const MemberExpr *E) {
// Handle static data members.
if (const VarDecl *VD = dyn_cast<VarDecl>(E->getMemberDecl())) {
  VisitIgnoredBaseExpression(E->getBase());
  return VisitVarDecl(E, VD);
}

// Handle static member functions.
if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(E->getMemberDecl())) {
  if (MD->isStatic()) {
    VisitIgnoredBaseExpression(E->getBase());
    return Success(MD);
  }
}

// Handle non-static data members.
return LValueExprEvaluatorBaseTy::VisitMemberExpr(E);
5353}

5355bool LValueExprEvaluator::VisitArraySubscriptExpr(const ArraySubscriptExpr *E) {
// FIXME: Deal with vectors as array subscript bases.
if (E->getBase()->getType()->isVectorType())
  return Error(E);

bool Success = true;
if (!evaluatePointer(E->getBase(), Result)) {
  if (!Info.noteFailure())
    return false;
  Success = false;
}

APSInt Index;
if (!EvaluateInteger(E->getIdx(), Index, Info))
  return false;

return Success &&
       HandleLValueArrayAdjustment(Info, E, Result, E->getType(), Index);
5373}

5375bool LValueExprEvaluator::VisitUnaryDeref(const UnaryOperator *E) {
return evaluatePointer(E->getSubExpr(), Result);
5377}

5379bool LValueExprEvaluator::VisitUnaryReal(const UnaryOperator *E) {
if (!Visit(E->getSubExpr()))
  return false;
// __real is a no-op on scalar lvalues.
if (E->getSubExpr()->getType()->isAnyComplexType())
  HandleLValueComplexElement(Info, E, Result, E->getType(), false);
return true;
5386}

5388bool LValueExprEvaluator::VisitUnaryImag(const UnaryOperator *E) {
assert(E->getSubExpr()->getType()->isAnyComplexType() &&(static_cast <bool> (E->getSubExpr()->getType()->
isAnyComplexType() && "lvalue __imag__ on scalar?") ?
 void (0) : __assert_fail ("E->getSubExpr()->getType()->isAnyComplexType() && \"lvalue __imag__ on scalar?\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 5390, __extension__ __PRETTY_FUNCTION__))
       "lvalue __imag__ on scalar?")(static_cast <bool> (E->getSubExpr()->getType()->
isAnyComplexType() && "lvalue __imag__ on scalar?") ?
 void (0) : __assert_fail ("E->getSubExpr()->getType()->isAnyComplexType() && \"lvalue __imag__ on scalar?\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 5390, __extension__ __PRETTY_FUNCTION__));
if (!Visit(E->getSubExpr()))
  return false;
HandleLValueComplexElement(Info, E, Result, E->getType(), true);
return true;
5395}

5397bool LValueExprEvaluator::VisitUnaryPreIncDec(const UnaryOperator *UO) {
if (!Info.getLangOpts().CPlusPlus14 && !Info.keepEvaluatingAfterFailure())
  return Error(UO);

if (!this->Visit(UO->getSubExpr()))
  return false;

return handleIncDec(
    this->Info, UO, Result, UO->getSubExpr()->getType(),
    UO->isIncrementOp(), nullptr);
5407}

5409bool LValueExprEvaluator::VisitCompoundAssignOperator(
  const CompoundAssignOperator *CAO) {
if (!Info.getLangOpts().CPlusPlus14 && !Info.keepEvaluatingAfterFailure())
  return Error(CAO);

APValue RHS;

// The overall lvalue result is the result of evaluating the LHS.
if (!this->Visit(CAO->getLHS())) {
  if (Info.noteFailure())
    Evaluate(RHS, this->Info, CAO->getRHS());
  return false;
}

if (!Evaluate(RHS, this->Info, CAO->getRHS()))
  return false;

return handleCompoundAssignment(
    this->Info, CAO,
    Result, CAO->getLHS()->getType(), CAO->getComputationLHSType(),
    CAO->getOpForCompoundAssignment(CAO->getOpcode()), RHS);
5430}

5432bool LValueExprEvaluator::VisitBinAssign(const BinaryOperator *E) {
if (!Info.getLangOpts().CPlusPlus14 && !Info.keepEvaluatingAfterFailure())
  return Error(E);

APValue NewVal;

if (!this->Visit(E->getLHS())) {
  if (Info.noteFailure())
    Evaluate(NewVal, this->Info, E->getRHS());
  return false;
}

if (!Evaluate(NewVal, this->Info, E->getRHS()))
  return false;

return handleAssignment(this->Info, E, Result, E->getLHS()->getType(),
                        NewVal);
5449}

5451//===----------------------------------------------------------------------===//
5452// Pointer Evaluation
5453//===----------------------------------------------------------------------===//

5455/// \brief Attempts to compute the number of bytes available at the pointer
5456/// returned by a function with the alloc_size attribute. Returns true if we
5457/// were successful. Places an unsigned number into `Result`.
5458///
5459/// This expects the given CallExpr to be a call to a function with an
5460/// alloc_size attribute.
5461static bool getBytesReturnedByAllocSizeCall(const ASTContext &Ctx,
                                          const CallExpr *Call,
                                          llvm::APInt &Result) {
const AllocSizeAttr *AllocSize = getAllocSizeAttr(Call);

// alloc_size args are 1-indexed, 0 means not present.
assert(AllocSize && AllocSize->getElemSizeParam() != 0)(static_cast <bool> (AllocSize && AllocSize->
getElemSizeParam() != 0) ? void (0) : __assert_fail ("AllocSize && AllocSize->getElemSizeParam() != 0"
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 5467, __extension__ __PRETTY_FUNCTION__));
unsigned SizeArgNo = AllocSize->getElemSizeParam() - 1;
unsigned BitsInSizeT = Ctx.getTypeSize(Ctx.getSizeType());
if (Call->getNumArgs() <= SizeArgNo)
  return false;

auto EvaluateAsSizeT = [&](const Expr *E, APSInt &Into) {
  if (!E->EvaluateAsInt(Into, Ctx, Expr::SE_AllowSideEffects))
    return false;
  if (Into.isNegative() || !Into.isIntN(BitsInSizeT))
    return false;
  Into = Into.zextOrSelf(BitsInSizeT);
  return true;
};

APSInt SizeOfElem;
if (!EvaluateAsSizeT(Call->getArg(SizeArgNo), SizeOfElem))
  return false;

if (!AllocSize->getNumElemsParam()) {
  Result = std::move(SizeOfElem);
  return true;
}

APSInt NumberOfElems;
// Argument numbers start at 1
unsigned NumArgNo = AllocSize->getNumElemsParam() - 1;
if (!EvaluateAsSizeT(Call->getArg(NumArgNo), NumberOfElems))
  return false;

bool Overflow;
llvm::APInt BytesAvailable = SizeOfElem.umul_ov(NumberOfElems, Overflow);
if (Overflow)
  return false;

Result = std::move(BytesAvailable);
return true;
5504}

5506/// \brief Convenience function. LVal's base must be a call to an alloc_size
5507/// function.
5508static bool getBytesReturnedByAllocSizeCall(const ASTContext &Ctx,
                                          const LValue &LVal,
                                          llvm::APInt &Result) {
assert(isBaseAnAllocSizeCall(LVal.getLValueBase()) &&(static_cast <bool> (isBaseAnAllocSizeCall(LVal.getLValueBase
()) && "Can't get the size of a non alloc_size function"
) ? void (0) : __assert_fail ("isBaseAnAllocSizeCall(LVal.getLValueBase()) && \"Can't get the size of a non alloc_size function\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 5512, __extension__ __PRETTY_FUNCTION__))
       "Can't get the size of a non alloc_size function")(static_cast <bool> (isBaseAnAllocSizeCall(LVal.getLValueBase
()) && "Can't get the size of a non alloc_size function"
) ? void (0) : __assert_fail ("isBaseAnAllocSizeCall(LVal.getLValueBase()) && \"Can't get the size of a non alloc_size function\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 5512, __extension__ __PRETTY_FUNCTION__));
const auto *Base = LVal.getLValueBase().get<const Expr *>();
const CallExpr *CE = tryUnwrapAllocSizeCall(Base);
return getBytesReturnedByAllocSizeCall(Ctx, CE, Result);
5516}

5518/// \brief Attempts to evaluate the given LValueBase as the result of a call to
5519/// a function with the alloc_size attribute. If it was possible to do so, this
5520/// function will return true, make Result's Base point to said function call,
5521/// and mark Result's Base as invalid.
5522static bool evaluateLValueAsAllocSize(EvalInfo &Info, APValue::LValueBase Base,
                                    LValue &Result) {
if (Base.isNull())
  return false;

// Because we do no form of static analysis, we only support const variables.
//
// Additionally, we can't support parameters, nor can we support static
// variables (in the latter case, use-before-assign isn't UB; in the former,
// we have no clue what they'll be assigned to).
const auto *VD =
    dyn_cast_or_null<VarDecl>(Base.dyn_cast<const ValueDecl *>());
if (!VD || !VD->isLocalVarDecl() || !VD->getType().isConstQualified())
  return false;

const Expr *Init = VD->getAnyInitializer();
if (!Init)
  return false;

const Expr *E = Init->IgnoreParens();
if (!tryUnwrapAllocSizeCall(E))
  return false;

// Store E instead of E unwrapped so that the type of the LValue's base is
// what the user wanted.
Result.setInvalid(E);

QualType Pointee = E->getType()->castAs<PointerType>()->getPointeeType();
Result.addUnsizedArray(Info, E, Pointee);
return true;
5552}

5554namespace {
5555class PointerExprEvaluator
: public ExprEvaluatorBase<PointerExprEvaluator> {
LValue &Result;
bool InvalidBaseOK;

bool Success(const Expr *E) {
  Result.set(E);
  return true;
}

bool evaluateLValue(const Expr *E, LValue &Result) {
  return EvaluateLValue(E, Result, Info, InvalidBaseOK);
}

bool evaluatePointer(const Expr *E, LValue &Result) {
  return EvaluatePointer(E, Result, Info, InvalidBaseOK);
}

bool visitNonBuiltinCallExpr(const CallExpr *E);
5574public:

PointerExprEvaluator(EvalInfo &info, LValue &Result, bool InvalidBaseOK)
    : ExprEvaluatorBaseTy(info), Result(Result),
      InvalidBaseOK(InvalidBaseOK) {}

bool Success(const APValue &V, const Expr *E) {
  Result.setFrom(Info.Ctx, V);
  return true;
}
bool ZeroInitialization(const Expr *E) {
  auto TargetVal = Info.Ctx.getTargetNullPointerValue(E->getType());
  Result.setNull(E->getType(), TargetVal);
  return true;
}

bool VisitBinaryOperator(const BinaryOperator *E);
bool VisitCastExpr(const CastExpr* E);
bool VisitUnaryAddrOf(const UnaryOperator *E);
bool VisitObjCStringLiteral(const ObjCStringLiteral *E)
    { return Success(E); }
bool VisitObjCBoxedExpr(const ObjCBoxedExpr *E) {
  if (Info.noteFailure())
    EvaluateIgnoredValue(Info, E->getSubExpr());
  return Error(E);
}
bool VisitAddrLabelExpr(const AddrLabelExpr *E)
    { return Success(E); }
bool VisitCallExpr(const CallExpr *E);
bool VisitBuiltinCallExpr(const CallExpr *E, unsigned BuiltinOp);
bool VisitBlockExpr(const BlockExpr *E) {
  if (!E->getBlockDecl()->hasCaptures())
    return Success(E);
  return Error(E);
}
bool VisitCXXThisExpr(const CXXThisExpr *E) {
  // Can't look at 'this' when checking a potential constant expression.
  if (Info.checkingPotentialConstantExpression())
    return false;
  if (!Info.CurrentCall->This) {
    if (Info.getLangOpts().CPlusPlus11)
      Info.FFDiag(E, diag::note_constexpr_this) << E->isImplicit();
    else
      Info.FFDiag(E);
    return false;
  }
  Result = *Info.CurrentCall->This;
  // If we are inside a lambda's call operator, the 'this' expression refers
  // to the enclosing '*this' object (either by value or reference) which is
  // either copied into the closure object's field that represents the '*this'
  // or refers to '*this'.
  if (isLambdaCallOperator(Info.CurrentCall->Callee)) {
    // Update 'Result' to refer to the data member/field of the closure object
    // that represents the '*this' capture.
    if (!HandleLValueMember(Info, E, Result,
                           Info.CurrentCall->LambdaThisCaptureField)) 
      return false;
    // If we captured '*this' by reference, replace the field with its referent.
    if (Info.CurrentCall->LambdaThisCaptureField->getType()
            ->isPointerType()) {
      APValue RVal;
      if (!handleLValueToRValueConversion(Info, E, E->getType(), Result,
                                          RVal))
        return false;

      Result.setFrom(Info.Ctx, RVal);
    }
  }
  return true;
}

// FIXME: Missing: @protocol, @selector
5646};
5647} // end anonymous namespace

5649static bool EvaluatePointer(const Expr* E, LValue& Result, EvalInfo &Info,
                          bool InvalidBaseOK) {
assert(E->isRValue() && E->getType()->hasPointerRepresentation())(static_cast <bool> (E->isRValue() && E->
getType()->hasPointerRepresentation()) ? void (0) : __assert_fail
 ("E->isRValue() && E->getType()->hasPointerRepresentation()"
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 5651, __extension__ __PRETTY_FUNCTION__));
return PointerExprEvaluator(Info, Result, InvalidBaseOK).Visit(E);
5653}

5655bool PointerExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) {
if (E->getOpcode() != BO_Add &&
    E->getOpcode() != BO_Sub)
  return ExprEvaluatorBaseTy::VisitBinaryOperator(E);

const Expr *PExp = E->getLHS();
const Expr *IExp = E->getRHS();
if (IExp->getType()->isPointerType())
  std::swap(PExp, IExp);

bool EvalPtrOK = evaluatePointer(PExp, Result);
if (!EvalPtrOK && !Info.noteFailure())
  return false;

llvm::APSInt Offset;
if (!EvaluateInteger(IExp, Offset, Info) || !EvalPtrOK)
  return false;

if (E->getOpcode() == BO_Sub)
  negateAsSigned(Offset);

QualType Pointee = PExp->getType()->castAs<PointerType>()->getPointeeType();
return HandleLValueArrayAdjustment(Info, E, Result, Pointee, Offset);
5678}

5680bool PointerExprEvaluator::VisitUnaryAddrOf(const UnaryOperator *E) {
return evaluateLValue(E->getSubExpr(), Result);
5682}

5684bool PointerExprEvaluator::VisitCastExpr(const CastExpr* E) {
const Expr* SubExpr = E->getSubExpr();

switch (E->getCastKind()) {
default:
  break;

case CK_BitCast:
case CK_CPointerToObjCPointerCast:
case CK_BlockPointerToObjCPointerCast:
case CK_AnyPointerToBlockPointerCast:
case CK_AddressSpaceConversion:
  if (!Visit(SubExpr))
    return false;
  // Bitcasts to cv void* are static_casts, not reinterpret_casts, so are
  // permitted in constant expressions in C++11. Bitcasts from cv void* are
  // also static_casts, but we disallow them as a resolution to DR1312.
  if (!E->getType()->isVoidPointerType()) {
    Result.Designator.setInvalid();
    if (SubExpr->getType()->isVoidPointerType())
      CCEDiag(E, diag::note_constexpr_invalid_cast)
        << 3 << SubExpr->getType();
    else
      CCEDiag(E, diag::note_constexpr_invalid_cast) << 2;
  }
  if (E->getCastKind() == CK_AddressSpaceConversion && Result.IsNullPtr)
    ZeroInitialization(E);
  return true;

case CK_DerivedToBase:
case CK_UncheckedDerivedToBase:
  if (!evaluatePointer(E->getSubExpr(), Result))
    return false;
  if (!Result.Base && Result.Offset.isZero())
    return true;

  // Now figure out the necessary offset to add to the base LV to get from
  // the derived class to the base class.
  return HandleLValueBasePath(Info, E, E->getSubExpr()->getType()->
                                castAs<PointerType>()->getPointeeType(),
                              Result);

case CK_BaseToDerived:
  if (!Visit(E->getSubExpr()))
    return false;
  if (!Result.Base && Result.Offset.isZero())
    return true;
  return HandleBaseToDerivedCast(Info, E, Result);

case CK_NullToPointer:
  VisitIgnoredValue(E->getSubExpr());
  return ZeroInitialization(E);

case CK_IntegralToPointer: {
  CCEDiag(E, diag::note_constexpr_invalid_cast) << 2;

  APValue Value;
  if (!EvaluateIntegerOrLValue(SubExpr, Value, Info))
    break;

  if (Value.isInt()) {
    unsigned Size = Info.Ctx.getTypeSize(E->getType());
    uint64_t N = Value.getInt().extOrTrunc(Size).getZExtValue();
    Result.Base = (Expr*)nullptr;
    Result.InvalidBase = false;
    Result.Offset = CharUnits::fromQuantity(N);
    Result.CallIndex = 0;
    Result.Designator.setInvalid();
    Result.IsNullPtr = false;
    return true;
  } else {
    // Cast is of an lvalue, no need to change value.
    Result.setFrom(Info.Ctx, Value);
    return true;
  }
}

case CK_ArrayToPointerDecay: {
  if (SubExpr->isGLValue()) {
    if (!evaluateLValue(SubExpr, Result))
      return false;
  } else {
    Result.set(SubExpr, Info.CurrentCall->Index);
    if (!EvaluateInPlace(Info.CurrentCall->createTemporary(SubExpr, false),
                         Info, Result, SubExpr))
      return false;
  }
  // The result is a pointer to the first element of the array.
  auto *AT = Info.Ctx.getAsArrayType(SubExpr->getType());
  if (auto *CAT = dyn_cast<ConstantArrayType>(AT))
    Result.addArray(Info, E, CAT);
  else
    Result.addUnsizedArray(Info, E, AT->getElementType());
  return true;
}

case CK_FunctionToPointerDecay:
  return evaluateLValue(SubExpr, Result);

case CK_LValueToRValue: {
  LValue LVal;
  if (!evaluateLValue(E->getSubExpr(), LVal))
    return false;

  APValue RVal;
  // Note, we use the subexpression's type in order to retain cv-qualifiers.
  if (!handleLValueToRValueConversion(Info, E, E->getSubExpr()->getType(),
                                      LVal, RVal))
    return InvalidBaseOK &&
           evaluateLValueAsAllocSize(Info, LVal.Base, Result);
  return Success(RVal, E);
}
}

return ExprEvaluatorBaseTy::VisitCastExpr(E);
5799}

5801static CharUnits GetAlignOfType(EvalInfo &Info, QualType T) {
// C++ [expr.alignof]p3:
//     When alignof is applied to a reference type, the result is the
//     alignment of the referenced type.
if (const ReferenceType *Ref = T->getAs<ReferenceType>())
  T = Ref->getPointeeType();

// __alignof is defined to return the preferred alignment.
if (T.getQualifiers().hasUnaligned())
  return CharUnits::One();
return Info.Ctx.toCharUnitsFromBits(
  Info.Ctx.getPreferredTypeAlign(T.getTypePtr()));
5813}

5815static CharUnits GetAlignOfExpr(EvalInfo &Info, const Expr *E) {
E = E->IgnoreParens();

// The kinds of expressions that we have special-case logic here for
// should be kept up to date with the special checks for those
// expressions in Sema.

// alignof decl is always accepted, even if it doesn't make sense: we default
// to 1 in those cases.
if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E))
  return Info.Ctx.getDeclAlign(DRE->getDecl(),
                               /*RefAsPointee*/true);

if (const MemberExpr *ME = dyn_cast<MemberExpr>(E))
  return Info.Ctx.getDeclAlign(ME->getMemberDecl(),
                               /*RefAsPointee*/true);

return GetAlignOfType(Info, E->getType());
5833}

5835// To be clear: this happily visits unsupported builtins. Better name welcomed.
5836bool PointerExprEvaluator::visitNonBuiltinCallExpr(const CallExpr *E) {
if (ExprEvaluatorBaseTy::VisitCallExpr(E))
  return true;

if (!(InvalidBaseOK && getAllocSizeAttr(E)))
  return false;

Result.setInvalid(E);
QualType PointeeTy = E->getType()->castAs<PointerType>()->getPointeeType();
Result.addUnsizedArray(Info, E, PointeeTy);
return true;
5847}

5849bool PointerExprEvaluator::VisitCallExpr(const CallExpr *E) {
if (IsStringLiteralCall(E))
  return Success(E);

if (unsigned BuiltinOp = E->getBuiltinCallee())
  return VisitBuiltinCallExpr(E, BuiltinOp);

return visitNonBuiltinCallExpr(E);
5857}

5859bool PointerExprEvaluator::VisitBuiltinCallExpr(const CallExpr *E,
                                              unsigned BuiltinOp) {
switch (BuiltinOp) {
case Builtin::BI__builtin_addressof:
  return evaluateLValue(E->getArg(0), Result);
case Builtin::BI__builtin_assume_aligned: {
  // We need to be very careful here because: if the pointer does not have the
  // asserted alignment, then the behavior is undefined, and undefined
  // behavior is non-constant.
  if (!evaluatePointer(E->getArg(0), Result))
    return false;

  LValue OffsetResult(Result);
  APSInt Alignment;
  if (!EvaluateInteger(E->getArg(1), Alignment, Info))
    return false;
  CharUnits Align = CharUnits::fromQuantity(Alignment.getZExtValue());

  if (E->getNumArgs() > 2) {
    APSInt Offset;
    if (!EvaluateInteger(E->getArg(2), Offset, Info))
      return false;

    int64_t AdditionalOffset = -Offset.getZExtValue();
    OffsetResult.Offset += CharUnits::fromQuantity(AdditionalOffset);
  }

  // If there is a base object, then it must have the correct alignment.
  if (OffsetResult.Base) {
    CharUnits BaseAlignment;
    if (const ValueDecl *VD =
        OffsetResult.Base.dyn_cast<const ValueDecl*>()) {
      BaseAlignment = Info.Ctx.getDeclAlign(VD);
    } else {
      BaseAlignment =
        GetAlignOfExpr(Info, OffsetResult.Base.get<const Expr*>());
    }

    if (BaseAlignment < Align) {
      Result.Designator.setInvalid();
      // FIXME: Add support to Diagnostic for long / long long.
      CCEDiag(E->getArg(0),
              diag::note_constexpr_baa_insufficient_alignment) << 0
        << (unsigned)BaseAlignment.getQuantity()
        << (unsigned)Align.getQuantity();
      return false;
    }
  }

  // The offset must also have the correct alignment.
  if (OffsetResult.Offset.alignTo(Align) != OffsetResult.Offset) {
    Result.Designator.setInvalid();

    (OffsetResult.Base
         ? CCEDiag(E->getArg(0),
                   diag::note_constexpr_baa_insufficient_alignment) << 1
         : CCEDiag(E->getArg(0),
                   diag::note_constexpr_baa_value_insufficient_alignment))
      << (int)OffsetResult.Offset.getQuantity()
      << (unsigned)Align.getQuantity();
    return false;
  }

  return true;
}

case Builtin::BIstrchr:
case Builtin::BIwcschr:
case Builtin::BImemchr:
case Builtin::BIwmemchr:
  if (Info.getLangOpts().CPlusPlus11)
    Info.CCEDiag(E, diag::note_constexpr_invalid_function)
      << /*isConstexpr*/0 << /*isConstructor*/0
      << (std::string("'") + Info.Ctx.BuiltinInfo.getName(BuiltinOp) + "'");
  else
    Info.CCEDiag(E, diag::note_invalid_subexpr_in_const_expr);
  LLVM_FALLTHROUGH[[clang::fallthrough]];
case Builtin::BI__builtin_strchr:
case Builtin::BI__builtin_wcschr:
case Builtin::BI__builtin_memchr:
case Builtin::BI__builtin_char_memchr:
case Builtin::BI__builtin_wmemchr: {
  if (!Visit(E->getArg(0)))
    return false;
  APSInt Desired;
  if (!EvaluateInteger(E->getArg(1), Desired, Info))
    return false;
  uint64_t MaxLength = uint64_t(-1);
  if (BuiltinOp != Builtin::BIstrchr &&
      BuiltinOp != Builtin::BIwcschr &&
      BuiltinOp != Builtin::BI__builtin_strchr &&
      BuiltinOp != Builtin::BI__builtin_wcschr) {
    APSInt N;
    if (!EvaluateInteger(E->getArg(2), N, Info))
      return false;
    MaxLength = N.getExtValue();
  }

  QualType CharTy = E->getArg(0)->getType()->getPointeeType();

  // Figure out what value we're actually looking for (after converting to
  // the corresponding unsigned type if necessary).
  uint64_t DesiredVal;
  bool StopAtNull = false;
  switch (BuiltinOp) {
  case Builtin::BIstrchr:
  case Builtin::BI__builtin_strchr:
    // strchr compares directly to the passed integer, and therefore
    // always fails if given an int that is not a char.
    if (!APSInt::isSameValue(HandleIntToIntCast(Info, E, CharTy,
                                                E->getArg(1)->getType(),
                                                Desired),
                             Desired))
      return ZeroInitialization(E);
    StopAtNull = true;
    LLVM_FALLTHROUGH[[clang::fallthrough]];
  case Builtin::BImemchr:
  case Builtin::BI__builtin_memchr:
  case Builtin::BI__builtin_char_memchr:
    // memchr compares by converting both sides to unsigned char. That's also
    // correct for strchr if we get this far (to cope with plain char being
    // unsigned in the strchr case).
    DesiredVal = Desired.trunc(Info.Ctx.getCharWidth()).getZExtValue();
    break;

  case Builtin::BIwcschr:
  case Builtin::BI__builtin_wcschr:
    StopAtNull = true;
    LLVM_FALLTHROUGH[[clang::fallthrough]];
  case Builtin::BIwmemchr:
  case Builtin::BI__builtin_wmemchr:
    // wcschr and wmemchr are given a wchar_t to look for. Just use it.
    DesiredVal = Desired.getZExtValue();
    break;
  }

  for (; MaxLength; --MaxLength) {
    APValue Char;
    if (!handleLValueToRValueConversion(Info, E, CharTy, Result, Char) ||
        !Char.isInt())
      return false;
    if (Char.getInt().getZExtValue() == DesiredVal)
      return true;
    if (StopAtNull && !Char.getInt())
      break;
    if (!HandleLValueArrayAdjustment(Info, E, Result, CharTy, 1))
      return false;
  }
  // Not found: return nullptr.
  return ZeroInitialization(E);
}

default:
  return visitNonBuiltinCallExpr(E);
}
6014}

6016//===----------------------------------------------------------------------===//
6017// Member Pointer Evaluation
6018//===----------------------------------------------------------------------===//

6020namespace {
6021class MemberPointerExprEvaluator
: public ExprEvaluatorBase<MemberPointerExprEvaluator> {
MemberPtr &Result;

bool Success(const ValueDecl *D) {
  Result = MemberPtr(D);
  return true;
}
6029public:

MemberPointerExprEvaluator(EvalInfo &Info, MemberPtr &Result)
  : ExprEvaluatorBaseTy(Info), Result(Result) {}

bool Success(const APValue &V, const Expr *E) {
  Result.setFrom(V);
  return true;
}
bool ZeroInitialization(const Expr *E) {
  return Success((const ValueDecl*)nullptr);
}

bool VisitCastExpr(const CastExpr *E);
bool VisitUnaryAddrOf(const UnaryOperator *E);
6044};
6045} // end anonymous namespace

6047static bool EvaluateMemberPointer(const Expr *E, MemberPtr &Result,
                                EvalInfo &Info) {
assert(E->isRValue() && E->getType()->isMemberPointerType())(static_cast <bool> (E->isRValue() && E->
getType()->isMemberPointerType()) ? void (0) : __assert_fail
 ("E->isRValue() && E->getType()->isMemberPointerType()"
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 6049, __extension__ __PRETTY_FUNCTION__));
return MemberPointerExprEvaluator(Info, Result).Visit(E);
6051}

6053bool MemberPointerExprEvaluator::VisitCastExpr(const CastExpr *E) {
switch (E->getCastKind()) {
default:
  return ExprEvaluatorBaseTy::VisitCastExpr(E);

case CK_NullToMemberPointer:
  VisitIgnoredValue(E->getSubExpr());
  return ZeroInitialization(E);

case CK_BaseToDerivedMemberPointer: {
  if (!Visit(E->getSubExpr()))
    return false;
  if (E->path_empty())
    return true;
  // Base-to-derived member pointer casts store the path in derived-to-base
  // order, so iterate backwards. The CXXBaseSpecifier also provides us with
  // the wrong end of the derived->base arc, so stagger the path by one class.
  typedef std::reverse_iterator<CastExpr::path_const_iterator> ReverseIter;
  for (ReverseIter PathI(E->path_end() - 1), PathE(E->path_begin());
       PathI != PathE; ++PathI) {
    assert(!(*PathI)->isVirtual() && "memptr cast through vbase")(static_cast <bool> (!(*PathI)->isVirtual() &&
 "memptr cast through vbase") ? void (0) : __assert_fail ("!(*PathI)->isVirtual() && \"memptr cast through vbase\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 6073, __extension__ __PRETTY_FUNCTION__));
    const CXXRecordDecl *Derived = (*PathI)->getType()->getAsCXXRecordDecl();
    if (!Result.castToDerived(Derived))
      return Error(E);
  }
  const Type *FinalTy = E->getType()->castAs<MemberPointerType>()->getClass();
  if (!Result.castToDerived(FinalTy->getAsCXXRecordDecl()))
    return Error(E);
  return true;
}

case CK_DerivedToBaseMemberPointer:
  if (!Visit(E->getSubExpr()))
    return false;
  for (CastExpr::path_const_iterator PathI = E->path_begin(),
       PathE = E->path_end(); PathI != PathE; ++PathI) {
    assert(!(*PathI)->isVirtual() && "memptr cast through vbase")(static_cast <bool> (!(*PathI)->isVirtual() &&
 "memptr cast through vbase") ? void (0) : __assert_fail ("!(*PathI)->isVirtual() && \"memptr cast through vbase\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 6089, __extension__ __PRETTY_FUNCTION__));
    const CXXRecordDecl *Base = (*PathI)->getType()->getAsCXXRecordDecl();
    if (!Result.castToBase(Base))
      return Error(E);
  }
  return true;
}
6096}

6098bool MemberPointerExprEvaluator::VisitUnaryAddrOf(const UnaryOperator *E) {
// C++11 [expr.unary.op]p3 has very strict rules on how the address of a
// member can be formed.
return Success(cast<DeclRefExpr>(E->getSubExpr())->getDecl());
6102}

6104//===----------------------------------------------------------------------===//
6105// Record Evaluation
6106//===----------------------------------------------------------------------===//

6108namespace {
class RecordExprEvaluator
: public ExprEvaluatorBase<RecordExprEvaluator> {
  const LValue &This;
  APValue &Result;
public:

  RecordExprEvaluator(EvalInfo &info, const LValue &This, APValue &Result)
    : ExprEvaluatorBaseTy(info), This(This), Result(Result) {}

  bool Success(const APValue &V, const Expr *E) {
    Result = V;
    return true;
  }
  bool ZeroInitialization(const Expr *E) {
    return ZeroInitialization(E, E->getType());
  }
  bool ZeroInitialization(const Expr *E, QualType T);

  bool VisitCallExpr(const CallExpr *E) {
    return handleCallExpr(E, Result, &This);
  }
  bool VisitCastExpr(const CastExpr *E);
  bool VisitInitListExpr(const InitListExpr *E);
  bool VisitCXXConstructExpr(const CXXConstructExpr *E) {
    return VisitCXXConstructExpr(E, E->getType());
  }
  bool VisitLambdaExpr(const LambdaExpr *E);
  bool VisitCXXInheritedCtorInitExpr(const CXXInheritedCtorInitExpr *E);
  bool VisitCXXConstructExpr(const CXXConstructExpr *E, QualType T);
  bool VisitCXXStdInitializerListExpr(const CXXStdInitializerListExpr *E);
};
6140}

6142/// Perform zero-initialization on an object of non-union class type.
6143/// C++11 [dcl.init]p5:
6144///  To zero-initialize an object or reference of type T means:
6145///    [...]
6146///    -- if T is a (possibly cv-qualified) non-union class type,
6147///       each non-static data member and each base-class subobject is
6148///       zero-initialized
6149static bool HandleClassZeroInitialization(EvalInfo &Info, const Expr *E,
                                        const RecordDecl *RD,
                                        const LValue &This, APValue &Result) {
assert(!RD->isUnion() && "Expected non-union class type")(static_cast <bool> (!RD->isUnion() && "Expected non-union class type"
) ? void (0) : __assert_fail ("!RD->isUnion() && \"Expected non-union class type\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 6152, __extension__ __PRETTY_FUNCTION__));
const CXXRecordDecl *CD = dyn_cast<CXXRecordDecl>(RD);
Result = APValue(APValue::UninitStruct(), CD ? CD->getNumBases() : 0,
                 std::distance(RD->field_begin(), RD->field_end()));

if (RD->isInvalidDecl()) return false;
const ASTRecordLayout &Layout = Info.Ctx.getASTRecordLayout(RD);

if (CD) {
  unsigned Index = 0;
  for (CXXRecordDecl::base_class_const_iterator I = CD->bases_begin(),
         End = CD->bases_end(); I != End; ++I, ++Index) {
    const CXXRecordDecl *Base = I->getType()->getAsCXXRecordDecl();
    LValue Subobject = This;
    if (!HandleLValueDirectBase(Info, E, Subobject, CD, Base, &Layout))
      return false;
    if (!HandleClassZeroInitialization(Info, E, Base, Subobject,
                                       Result.getStructBase(Index)))
      return false;
  }
}

for (const auto *I : RD->fields()) {
  // -- if T is a reference type, no initialization is performed.
  if (I->getType()->isReferenceType())
    continue;

  LValue Subobject = This;
  if (!HandleLValueMember(Info, E, Subobject, I, &Layout))
    return false;

  ImplicitValueInitExpr VIE(I->getType());
  if (!EvaluateInPlace(
        Result.getStructField(I->getFieldIndex()), Info, Subobject, &VIE))
    return false;
}

return true;
6190}

6192bool RecordExprEvaluator::ZeroInitialization(const Expr *E, QualType T) {
const RecordDecl *RD = T->castAs<RecordType>()->getDecl();
if (RD->isInvalidDecl()) return false;
if (RD->isUnion()) {
  // C++11 [dcl.init]p5: If T is a (possibly cv-qualified) union type, the
  // object's first non-static named data member is zero-initialized
  RecordDecl::field_iterator I = RD->field_begin();
  if (I == RD->field_end()) {
    Result = APValue((const FieldDecl*)nullptr);
    return true;
  }

  LValue Subobject = This;
  if (!HandleLValueMember(Info, E, Subobject, *I))
    return false;
  Result = APValue(*I);
  ImplicitValueInitExpr VIE(I->getType());
  return EvaluateInPlace(Result.getUnionValue(), Info, Subobject, &VIE);
}

if (isa<CXXRecordDecl>(RD) && cast<CXXRecordDecl>(RD)->getNumVBases()) {
  Info.FFDiag(E, diag::note_constexpr_virtual_base) << RD;
  return false;
}

return HandleClassZeroInitialization(Info, E, RD, This, Result);
6218}

6220bool RecordExprEvaluator::VisitCastExpr(const CastExpr *E) {
switch (E->getCastKind()) {
default:
  return ExprEvaluatorBaseTy::VisitCastExpr(E);

case CK_ConstructorConversion:
  return Visit(E->getSubExpr());

case CK_DerivedToBase:
case CK_UncheckedDerivedToBase: {
  APValue DerivedObject;
  if (!Evaluate(DerivedObject, Info, E->getSubExpr()))
    return false;
  if (!DerivedObject.isStruct())
    return Error(E->getSubExpr());

  // Derived-to-base rvalue conversion: just slice off the derived part.
  APValue *Value = &DerivedObject;
  const CXXRecordDecl *RD = E->getSubExpr()->getType()->getAsCXXRecordDecl();
  for (CastExpr::path_const_iterator PathI = E->path_begin(),
       PathE = E->path_end(); PathI != PathE; ++PathI) {
    assert(!(*PathI)->isVirtual() && "record rvalue with virtual base")(static_cast <bool> (!(*PathI)->isVirtual() &&
 "record rvalue with virtual base") ? void (0) : __assert_fail
 ("!(*PathI)->isVirtual() && \"record rvalue with virtual base\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 6241, __extension__ __PRETTY_FUNCTION__));
    const CXXRecordDecl *Base = (*PathI)->getType()->getAsCXXRecordDecl();
    Value = &Value->getStructBase(getBaseIndex(RD, Base));
    RD = Base;
  }
  Result = *Value;
  return true;
}
}
6250}

6252bool RecordExprEvaluator::VisitInitListExpr(const InitListExpr *E) {
if (E->isTransparent())
  return Visit(E->getInit(0));

const RecordDecl *RD = E->getType()->castAs<RecordType>()->getDecl();
if (RD->isInvalidDecl()) return false;
const ASTRecordLayout &Layout = Info.Ctx.getASTRecordLayout(RD);

if (RD->isUnion()) {
  const FieldDecl *Field = E->getInitializedFieldInUnion();
  Result = APValue(Field);
  if (!Field)
    return true;

  // If the initializer list for a union does not contain any elements, the
  // first element of the union is value-initialized.
  // FIXME: The element should be initialized from an initializer list.
  //        Is this difference ever observable for initializer lists which
  //        we don't build?
  ImplicitValueInitExpr VIE(Field->getType());
  const Expr *InitExpr = E->getNumInits() ? E->getInit(0) : &VIE;

  LValue Subobject = This;
  if (!HandleLValueMember(Info, InitExpr, Subobject, Field, &Layout))
    return false;

  // Temporarily override This, in case there's a CXXDefaultInitExpr in here.
  ThisOverrideRAII ThisOverride(*Info.CurrentCall, &This,
                                isa<CXXDefaultInitExpr>(InitExpr));

  return EvaluateInPlace(Result.getUnionValue(), Info, Subobject, InitExpr);
}

auto *CXXRD = dyn_cast<CXXRecordDecl>(RD);
if (Result.isUninit())
  Result = APValue(APValue::UninitStruct(), CXXRD ? CXXRD->getNumBases() : 0,
                   std::distance(RD->field_begin(), RD->field_end()));
unsigned ElementNo = 0;
bool Success = true;

// Initialize base classes.
if (CXXRD) {
  for (const auto &Base : CXXRD->bases()) {
    assert(ElementNo < E->getNumInits() && "missing init for base class")(static_cast <bool> (ElementNo < E->getNumInits()
 && "missing init for base class") ? void (0) : __assert_fail
 ("ElementNo < E->getNumInits() && \"missing init for base class\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 6295, __extension__ __PRETTY_FUNCTION__));
    const Expr *Init = E->getInit(ElementNo);

    LValue Subobject = This;
    if (!HandleLValueBase(Info, Init, Subobject, CXXRD, &Base))
      return false;

    APValue &FieldVal = Result.getStructBase(ElementNo);
    if (!EvaluateInPlace(FieldVal, Info, Subobject, Init)) {
      if (!Info.noteFailure())
        return false;
      Success = false;
    }
    ++ElementNo;
  }
}

// Initialize members.
for (const auto *Field : RD->fields()) {
  // Anonymous bit-fields are not considered members of the class for
  // purposes of aggregate initialization.
  if (Field->isUnnamedBitfield())
    continue;

  LValue Subobject = This;

  bool HaveInit = ElementNo < E->getNumInits();

  // FIXME: Diagnostics here should point to the end of the initializer
  // list, not the start.
  if (!HandleLValueMember(Info, HaveInit ? E->getInit(ElementNo) : E,
                          Subobject, Field, &Layout))
    return false;

  // Perform an implicit value-initialization for members beyond the end of
  // the initializer list.
  ImplicitValueInitExpr VIE(HaveInit ? Info.Ctx.IntTy : Field->getType());
  const Expr *Init = HaveInit ? E->getInit(ElementNo++) : &VIE;

  // Temporarily override This, in case there's a CXXDefaultInitExpr in here.
  ThisOverrideRAII ThisOverride(*Info.CurrentCall, &This,
                                isa<CXXDefaultInitExpr>(Init));

  APValue &FieldVal = Result.getStructField(Field->getFieldIndex());
  if (!EvaluateInPlace(FieldVal, Info, Subobject, Init) ||
      (Field->isBitField() && !truncateBitfieldValue(Info, Init,
                                                     FieldVal, Field))) {
    if (!Info.noteFailure())
      return false;
    Success = false;
  }
}

return Success;
6349}

6351bool RecordExprEvaluator::VisitCXXConstructExpr(const CXXConstructExpr *E,
                                              QualType T) {
// Note that E's type is not necessarily the type of our class here; we might
// be initializing an array element instead.
const CXXConstructorDecl *FD = E->getConstructor();
if (FD->isInvalidDecl() || FD->getParent()->isInvalidDecl()) return false;

bool ZeroInit = E->requiresZeroInitialization();
if (CheckTrivialDefaultConstructor(Info, E->getExprLoc(), FD, ZeroInit)) {
  // If we've already performed zero-initialization, we're already done.
  if (!Result.isUninit())
    return true;

  // We can get here in two different ways:
  //  1) We're performing value-initialization, and should zero-initialize
  //     the object, or
  //  2) We're performing default-initialization of an object with a trivial
  //     constexpr default constructor, in which case we should start the
  //     lifetimes of all the base subobjects (there can be no data member
  //     subobjects in this case) per [basic.life]p1.
  // Either way, ZeroInitialization is appropriate.
  return ZeroInitialization(E, T);
}

const FunctionDecl *Definition = nullptr;
auto Body = FD->getBody(Definition);

if (!CheckConstexprFunction(Info, E->getExprLoc(), FD, Definition, Body))
  return false;

// Avoid materializing a temporary for an elidable copy/move constructor.
if (E->isElidable() && !ZeroInit)
  if (const MaterializeTemporaryExpr *ME
        = dyn_cast<MaterializeTemporaryExpr>(E->getArg(0)))
    return Visit(ME->GetTemporaryExpr());

if (ZeroInit && !ZeroInitialization(E, T))
  return false;

auto Args = llvm::makeArrayRef(E->getArgs(), E->getNumArgs());
return HandleConstructorCall(E, This, Args,
                             cast<CXXConstructorDecl>(Definition), Info,
                             Result);
6394}

6396bool RecordExprEvaluator::VisitCXXInheritedCtorInitExpr(
  const CXXInheritedCtorInitExpr *E) {
if (!Info.CurrentCall) {
  assert(Info.checkingPotentialConstantExpression())(static_cast <bool> (Info.checkingPotentialConstantExpression
()) ? void (0) : __assert_fail ("Info.checkingPotentialConstantExpression()"
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 6399, __extension__ __PRETTY_FUNCTION__));
  return false;
}

const CXXConstructorDecl *FD = E->getConstructor();
if (FD->isInvalidDecl() || FD->getParent()->isInvalidDecl())
  return false;

const FunctionDecl *Definition = nullptr;
auto Body = FD->getBody(Definition);

if (!CheckConstexprFunction(Info, E->getExprLoc(), FD, Definition, Body))
  return false;

return HandleConstructorCall(E, This, Info.CurrentCall->Arguments,
                             cast<CXXConstructorDecl>(Definition), Info,
                             Result);
6416}

6418bool RecordExprEvaluator::VisitCXXStdInitializerListExpr(
  const CXXStdInitializerListExpr *E) {
const ConstantArrayType *ArrayType =
    Info.Ctx.getAsConstantArrayType(E->getSubExpr()->getType());

LValue Array;
if (!EvaluateLValue(E->getSubExpr(), Array, Info))
  return false;

// Get a pointer to the first element of the array.
Array.addArray(Info, E, ArrayType);

// FIXME: Perform the checks on the field types in SemaInit.
RecordDecl *Record = E->getType()->castAs<RecordType>()->getDecl();
RecordDecl::field_iterator Field = Record->field_begin();
if (Field == Record->field_end())
  return Error(E);

// Start pointer.
if (!Field->getType()->isPointerType() ||
    !Info.Ctx.hasSameType(Field->getType()->getPointeeType(),
                          ArrayType->getElementType()))
  return Error(E);

// FIXME: What if the initializer_list type has base classes, etc?
Result = APValue(APValue::UninitStruct(), 0, 2);
Array.moveInto(Result.getStructField(0));

if (++Field == Record->field_end())
  return Error(E);

if (Field->getType()->isPointerType() &&
    Info.Ctx.hasSameType(Field->getType()->getPointeeType(),
                         ArrayType->getElementType())) {
  // End pointer.
  if (!HandleLValueArrayAdjustment(Info, E, Array,
                                   ArrayType->getElementType(),
                                   ArrayType->getSize().getZExtValue()))
    return false;
  Array.moveInto(Result.getStructField(1));
} else if (Info.Ctx.hasSameType(Field->getType(), Info.Ctx.getSizeType()))
  // Length.
  Result.getStructField(1) = APValue(APSInt(ArrayType->getSize()));
else
  return Error(E);

if (++Field != Record->field_end())
  return Error(E);

return true;
6468}

6470bool RecordExprEvaluator::VisitLambdaExpr(const LambdaExpr *E) {
const CXXRecordDecl *ClosureClass = E->getLambdaClass();
if (ClosureClass->isInvalidDecl()) return false;

if (Info.checkingPotentialConstantExpression()) return true;

const size_t NumFields =
    std::distance(ClosureClass->field_begin(), ClosureClass->field_end());

assert(NumFields == (size_t)std::distance(E->capture_init_begin(),(static_cast <bool> (NumFields == (size_t)std::distance
(E->capture_init_begin(), E->capture_init_end()) &&
 "The number of lambda capture initializers should equal the number of "
 "fields within the closure type") ? void (0) : __assert_fail
 ("NumFields == (size_t)std::distance(E->capture_init_begin(), E->capture_init_end()) && \"The number of lambda capture initializers should equal the number of \" \"fields within the closure type\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 6482, __extension__ __PRETTY_FUNCTION__))
                                          E->capture_init_end()) &&(static_cast <bool> (NumFields == (size_t)std::distance
(E->capture_init_begin(), E->capture_init_end()) &&
 "The number of lambda capture initializers should equal the number of "
 "fields within the closure type") ? void (0) : __assert_fail
 ("NumFields == (size_t)std::distance(E->capture_init_begin(), E->capture_init_end()) && \"The number of lambda capture initializers should equal the number of \" \"fields within the closure type\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 6482, __extension__ __PRETTY_FUNCTION__))
       "The number of lambda capture initializers should equal the number of "(static_cast <bool> (NumFields == (size_t)std::distance
(E->capture_init_begin(), E->capture_init_end()) &&
 "The number of lambda capture initializers should equal the number of "
 "fields within the closure type") ? void (0) : __assert_fail
 ("NumFields == (size_t)std::distance(E->capture_init_begin(), E->capture_init_end()) && \"The number of lambda capture initializers should equal the number of \" \"fields within the closure type\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 6482, __extension__ __PRETTY_FUNCTION__))
       "fields within the closure type")(static_cast <bool> (NumFields == (size_t)std::distance
(E->capture_init_begin(), E->capture_init_end()) &&
 "The number of lambda capture initializers should equal the number of "
 "fields within the closure type") ? void (0) : __assert_fail
 ("NumFields == (size_t)std::distance(E->capture_init_begin(), E->capture_init_end()) && \"The number of lambda capture initializers should equal the number of \" \"fields within the closure type\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 6482, __extension__ __PRETTY_FUNCTION__));

Result = APValue(APValue::UninitStruct(), /*NumBases*/0, NumFields);
// Iterate through all the lambda's closure object's fields and initialize
// them.
auto *CaptureInitIt = E->capture_init_begin();
const LambdaCapture *CaptureIt = ClosureClass->captures_begin();
bool Success = true;
for (const auto *Field : ClosureClass->fields()) {
  assert(CaptureInitIt != E->capture_init_end())(static_cast <bool> (CaptureInitIt != E->capture_init_end
()) ? void (0) : __assert_fail ("CaptureInitIt != E->capture_init_end()"
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 6491, __extension__ __PRETTY_FUNCTION__));
  // Get the initializer for this field
  Expr *const CurFieldInit = *CaptureInitIt++;
  
  // If there is no initializer, either this is a VLA or an error has
  // occurred.
  if (!CurFieldInit)
    return Error(E);

  APValue &FieldVal = Result.getStructField(Field->getFieldIndex());
  if (!EvaluateInPlace(FieldVal, Info, This, CurFieldInit)) {
    if (!Info.keepEvaluatingAfterFailure())
      return false;
    Success = false;
  }
  ++CaptureIt;
}
return Success;
6509}

6511static bool EvaluateRecord(const Expr *E, const LValue &This,
                         APValue &Result, EvalInfo &Info) {
assert(E->isRValue() && E->getType()->isRecordType() &&(static_cast <bool> (E->isRValue() && E->
getType()->isRecordType() && "can't evaluate expression as a record rvalue"
) ? void (0) : __assert_fail ("E->isRValue() && E->getType()->isRecordType() && \"can't evaluate expression as a record rvalue\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 6514, __extension__ __PRETTY_FUNCTION__))
       "can't evaluate expression as a record rvalue")(static_cast <bool> (E->isRValue() && E->
getType()->isRecordType() && "can't evaluate expression as a record rvalue"
) ? void (0) : __assert_fail ("E->isRValue() && E->getType()->isRecordType() && \"can't evaluate expression as a record rvalue\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 6514, __extension__ __PRETTY_FUNCTION__));
return RecordExprEvaluator(Info, This, Result).Visit(E);
6516}

6518//===----------------------------------------------------------------------===//
6519// Temporary Evaluation
6520//
6521// Temporaries are represented in the AST as rvalues, but generally behave like
6522// lvalues. The full-object of which the temporary is a subobject is implicitly
6523// materialized so that a reference can bind to it.
6524//===----------------------------------------------------------------------===//
6525namespace {
6526class TemporaryExprEvaluator
: public LValueExprEvaluatorBase<TemporaryExprEvaluator> {
6528public:
TemporaryExprEvaluator(EvalInfo &Info, LValue &Result) :
  LValueExprEvaluatorBaseTy(Info, Result, false) {}

/// Visit an expression which constructs the value of this temporary.
bool VisitConstructExpr(const Expr *E) {
  Result.set(E, Info.CurrentCall->Index);
  return EvaluateInPlace(Info.CurrentCall->createTemporary(E, false),
                         Info, Result, E);
}

bool VisitCastExpr(const CastExpr *E) {
  switch (E->getCastKind()) {
  default:
    return LValueExprEvaluatorBaseTy::VisitCastExpr(E);

  case CK_ConstructorConversion:
    return VisitConstructExpr(E->getSubExpr());
  }
}
bool VisitInitListExpr(const InitListExpr *E) {
  return VisitConstructExpr(E);
}
bool VisitCXXConstructExpr(const CXXConstructExpr *E) {
  return VisitConstructExpr(E);
}
bool VisitCallExpr(const CallExpr *E) {
  return VisitConstructExpr(E);
}
bool VisitCXXStdInitializerListExpr(const CXXStdInitializerListExpr *E) {
  return VisitConstructExpr(E);
}
bool VisitLambdaExpr(const LambdaExpr *E) {
  return VisitConstructExpr(E);
}
6563};
6564} // end anonymous namespace

6566/// Evaluate an expression of record type as a temporary.
6567static bool EvaluateTemporary(const Expr *E, LValue &Result, EvalInfo &Info) {
assert(E->isRValue() && E->getType()->isRecordType())(static_cast <bool> (E->isRValue() && E->
getType()->isRecordType()) ? void (0) : __assert_fail ("E->isRValue() && E->getType()->isRecordType()"
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 6568, __extension__ __PRETTY_FUNCTION__));
return TemporaryExprEvaluator(Info, Result).Visit(E);
6570}

6572//===----------------------------------------------------------------------===//
6573// Vector Evaluation
6574//===----------------------------------------------------------------------===//

6576namespace {
class VectorExprEvaluator
: public ExprEvaluatorBase<VectorExprEvaluator> {
  APValue &Result;
public:

  VectorExprEvaluator(EvalInfo &info, APValue &Result)
    : ExprEvaluatorBaseTy(info), Result(Result) {}

  bool Success(ArrayRef<APValue> V, const Expr *E) {
    assert(V.size() == E->getType()->castAs<VectorType>()->getNumElements())(static_cast <bool> (V.size() == E->getType()->castAs
<VectorType>()->getNumElements()) ? void (0) : __assert_fail
 ("V.size() == E->getType()->castAs<VectorType>()->getNumElements()"
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 6586, __extension__ __PRETTY_FUNCTION__));
    // FIXME: remove this APValue copy.
    Result = APValue(V.data(), V.size());
    return true;
  }
  bool Success(const APValue &V, const Expr *E) {
    assert(V.isVector())(static_cast <bool> (V.isVector()) ? void (0) : __assert_fail
 ("V.isVector()", "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 6592, __extension__ __PRETTY_FUNCTION__));
    Result = V;
    return true;
  }
  bool ZeroInitialization(const Expr *E);

  bool VisitUnaryReal(const UnaryOperator *E)
    { return Visit(E->getSubExpr()); }
  bool VisitCastExpr(const CastExpr* E);
  bool VisitInitListExpr(const InitListExpr *E);
  bool VisitUnaryImag(const UnaryOperator *E);
  // FIXME: Missing: unary -, unary ~, binary add/sub/mul/div,
  //                 binary comparisons, binary and/or/xor,
  //                 shufflevector, ExtVectorElementExpr
};
6607} // end anonymous namespace

6609static bool EvaluateVector(const Expr* E, APValue& Result, EvalInfo &Info) {
assert(E->isRValue() && E->getType()->isVectorType() &&"not a vector rvalue")(static_cast <bool> (E->isRValue() && E->
getType()->isVectorType() &&"not a vector rvalue")
 ? void (0) : __assert_fail ("E->isRValue() && E->getType()->isVectorType() &&\"not a vector rvalue\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 6610, __extension__ __PRETTY_FUNCTION__));
return VectorExprEvaluator(Info, Result).Visit(E);
6612}

6614bool VectorExprEvaluator::VisitCastExpr(const CastExpr *E) {
const VectorType *VTy = E->getType()->castAs<VectorType>();
unsigned NElts = VTy->getNumElements();

const Expr *SE = E->getSubExpr();
QualType SETy = SE->getType();

switch (E->getCastKind()) {
case CK_VectorSplat: {
  APValue Val = APValue();
  if (SETy->isIntegerType()) {
    APSInt IntResult;
    if (!EvaluateInteger(SE, IntResult, Info))
      return false;
    Val = APValue(std::move(IntResult));
  } else if (SETy->isRealFloatingType()) {
    APFloat FloatResult(0.0);
    if (!EvaluateFloat(SE, FloatResult, Info))
      return false;
    Val = APValue(std::move(FloatResult));
  } else {
    return Error(E);
  }

  // Splat and create vector APValue.
  SmallVector<APValue, 4> Elts(NElts, Val);
  return Success(Elts, E);
}
case CK_BitCast: {
  // Evaluate the operand into an APInt we can extract from.
  llvm::APInt SValInt;
  if (!EvalAndBitcastToAPInt(Info, SE, SValInt))
    return false;
  // Extract the elements
  QualType EltTy = VTy->getElementType();
  unsigned EltSize = Info.Ctx.getTypeSize(EltTy);
  bool BigEndian = Info.Ctx.getTargetInfo().isBigEndian();
  SmallVector<APValue, 4> Elts;
  if (EltTy->isRealFloatingType()) {
    const llvm::fltSemantics &Sem = Info.Ctx.getFloatTypeSemantics(EltTy);
    unsigned FloatEltSize = EltSize;
    if (&Sem == &APFloat::x87DoubleExtended())
      FloatEltSize = 80;
    for (unsigned i = 0; i < NElts; i++) {
      llvm::APInt Elt;
      if (BigEndian)
        Elt = SValInt.rotl(i*EltSize+FloatEltSize).trunc(FloatEltSize);
      else
        Elt = SValInt.rotr(i*EltSize).trunc(FloatEltSize);
      Elts.push_back(APValue(APFloat(Sem, Elt)));
    }
  } else if (EltTy->isIntegerType()) {
    for (unsigned i = 0; i < NElts; i++) {
      llvm::APInt Elt;
      if (BigEndian)
        Elt = SValInt.rotl(i*EltSize+EltSize).zextOrTrunc(EltSize);
      else
        Elt = SValInt.rotr(i*EltSize).zextOrTrunc(EltSize);
      Elts.push_back(APValue(APSInt(Elt, EltTy->isSignedIntegerType())));
    }
  } else {
    return Error(E);
  }
  return Success(Elts, E);
}
default:
  return ExprEvaluatorBaseTy::VisitCastExpr(E);
}
6682}

6684bool
6685VectorExprEvaluator::VisitInitListExpr(const InitListExpr *E) {
const VectorType *VT = E->getType()->castAs<VectorType>();
unsigned NumInits = E->getNumInits();
unsigned NumElements = VT->getNumElements();

QualType EltTy = VT->getElementType();
SmallVector<APValue, 4> Elements;

// The number of initializers can be less than the number of
// vector elements. For OpenCL, this can be due to nested vector
// initialization. For GCC compatibility, missing trailing elements 
// should be initialized with zeroes.
unsigned CountInits = 0, CountElts = 0;
while (CountElts < NumElements) {
  // Handle nested vector initialization.
  if (CountInits < NumInits 
      && E->getInit(CountInits)->getType()->isVectorType()) {
    APValue v;
    if (!EvaluateVector(E->getInit(CountInits), v, Info))
      return Error(E);
    unsigned vlen = v.getVectorLength();
    for (unsigned j = 0; j < vlen; j++) 
      Elements.push_back(v.getVectorElt(j));
    CountElts += vlen;
  } else if (EltTy->isIntegerType()) {
    llvm::APSInt sInt(32);
    if (CountInits < NumInits) {
      if (!EvaluateInteger(E->getInit(CountInits), sInt, Info))
        return false;
    } else // trailing integer zero.
      sInt = Info.Ctx.MakeIntValue(0, EltTy);
    Elements.push_back(APValue(sInt));
    CountElts++;
  } else {
    llvm::APFloat f(0.0);
    if (CountInits < NumInits) {
      if (!EvaluateFloat(E->getInit(CountInits), f, Info))
        return false;
    } else // trailing float zero.
      f = APFloat::getZero(Info.Ctx.getFloatTypeSemantics(EltTy));
    Elements.push_back(APValue(f));
    CountElts++;
  }
  CountInits++;
}
return Success(Elements, E);
6731}

6733bool
6734VectorExprEvaluator::ZeroInitialization(const Expr *E) {
const VectorType *VT = E->getType()->getAs<VectorType>();
QualType EltTy = VT->getElementType();
APValue ZeroElement;
if (EltTy->isIntegerType())
  ZeroElement = APValue(Info.Ctx.MakeIntValue(0, EltTy));
else
  ZeroElement =
      APValue(APFloat::getZero(Info.Ctx.getFloatTypeSemantics(EltTy)));

SmallVector<APValue, 4> Elements(VT->getNumElements(), ZeroElement);
return Success(Elements, E);
6746}

6748bool VectorExprEvaluator::VisitUnaryImag(const UnaryOperator *E) {
VisitIgnoredValue(E->getSubExpr());
return ZeroInitialization(E);
6751}

6753//===----------------------------------------------------------------------===//
6754// Array Evaluation
6755//===----------------------------------------------------------------------===//

6757namespace {
class ArrayExprEvaluator
: public ExprEvaluatorBase<ArrayExprEvaluator> {
  const LValue &This;
  APValue &Result;
public:

  ArrayExprEvaluator(EvalInfo &Info, const LValue &This, APValue &Result)
    : ExprEvaluatorBaseTy(Info), This(This), Result(Result) {}

  bool Success(const APValue &V, const Expr *E) {
    assert((V.isArray() || V.isLValue()) &&(static_cast <bool> ((V.isArray() || V.isLValue()) &&
 "expected array or string literal") ? void (0) : __assert_fail
 ("(V.isArray() || V.isLValue()) && \"expected array or string literal\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 6769, __extension__ __PRETTY_FUNCTION__))
           "expected array or string literal")(static_cast <bool> ((V.isArray() || V.isLValue()) &&
 "expected array or string literal") ? void (0) : __assert_fail
 ("(V.isArray() || V.isLValue()) && \"expected array or string literal\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 6769, __extension__ __PRETTY_FUNCTION__));
    Result = V;
    return true;
  }

  bool ZeroInitialization(const Expr *E) {
    const ConstantArrayType *CAT =
        Info.Ctx.getAsConstantArrayType(E->getType());
    if (!CAT)
      return Error(E);

    Result = APValue(APValue::UninitArray(), 0,
                     CAT->getSize().getZExtValue());
    if (!Result.hasArrayFiller()) return true;

    // Zero-initialize all elements.
    LValue Subobject = This;
    Subobject.addArray(Info, E, CAT);
    ImplicitValueInitExpr VIE(CAT->getElementType());
    return EvaluateInPlace(Result.getArrayFiller(), Info, Subobject, &VIE);
  }

  bool VisitCallExpr(const CallExpr *E) {
    return handleCallExpr(E, Result, &This);
  }
  bool VisitInitListExpr(const InitListExpr *E);
  bool VisitArrayInitLoopExpr(const ArrayInitLoopExpr *E);
  bool VisitCXXConstructExpr(const CXXConstructExpr *E);
  bool VisitCXXConstructExpr(const CXXConstructExpr *E,
                             const LValue &Subobject,
                             APValue *Value, QualType Type);
};
6801} // end anonymous namespace

6803static bool EvaluateArray(const Expr *E, const LValue &This,
                        APValue &Result, EvalInfo &Info) {
assert(E->isRValue() && E->getType()->isArrayType() && "not an array rvalue")(static_cast <bool> (E->isRValue() && E->
getType()->isArrayType() && "not an array rvalue")
 ? void (0) : __assert_fail ("E->isRValue() && E->getType()->isArrayType() && \"not an array rvalue\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 6805, __extension__ __PRETTY_FUNCTION__));
return ArrayExprEvaluator(Info, This, Result).Visit(E);
6807}

6809// Return true iff the given array filler may depend on the element index.
6810static bool MaybeElementDependentArrayFiller(const Expr *FillerExpr) {
// For now, just whitelist non-class value-initialization and initialization
// lists comprised of them.
if (isa<ImplicitValueInitExpr>(FillerExpr))
  return false;
if (const InitListExpr *ILE = dyn_cast<InitListExpr>(FillerExpr)) {
  for (unsigned I = 0, E = ILE->getNumInits(); I != E; ++I) {
    if (MaybeElementDependentArrayFiller(ILE->getInit(I)))
      return true;
  }
  return false;
}
return true;
6823}

6825bool ArrayExprEvaluator::VisitInitListExpr(const InitListExpr *E) {
const ConstantArrayType *CAT = Info.Ctx.getAsConstantArrayType(E->getType());
if (!CAT)
  return Error(E);

// C++11 [dcl.init.string]p1: A char array [...] can be initialized by [...]
// an appropriately-typed string literal enclosed in braces.
if (E->isStringLiteralInit()) {
  LValue LV;
  if (!EvaluateLValue(E->getInit(0), LV, Info))
    return false;
  APValue Val;
  LV.moveInto(Val);
  return Success(Val, E);
}

bool Success = true;

assert((!Result.isArray() || Result.getArrayInitializedElts() == 0) &&(static_cast <bool> ((!Result.isArray() || Result.getArrayInitializedElts
() == 0) && "zero-initialized array shouldn't have any initialized elts"
) ? void (0) : __assert_fail ("(!Result.isArray() || Result.getArrayInitializedElts() == 0) && \"zero-initialized array shouldn't have any initialized elts\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 6844, __extension__ __PRETTY_FUNCTION__))
       "zero-initialized array shouldn't have any initialized elts")(static_cast <bool> ((!Result.isArray() || Result.getArrayInitializedElts
() == 0) && "zero-initialized array shouldn't have any initialized elts"
) ? void (0) : __assert_fail ("(!Result.isArray() || Result.getArrayInitializedElts() == 0) && \"zero-initialized array shouldn't have any initialized elts\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 6844, __extension__ __PRETTY_FUNCTION__));
APValue Filler;
if (Result.isArray() && Result.hasArrayFiller())
  Filler = Result.getArrayFiller();

unsigned NumEltsToInit = E->getNumInits();
unsigned NumElts = CAT->getSize().getZExtValue();
const Expr *FillerExpr = E->hasArrayFiller() ? E->getArrayFiller() : nullptr;

// If the initializer might depend on the array index, run it for each
// array element.
if (NumEltsToInit != NumElts && MaybeElementDependentArrayFiller(FillerExpr))
  NumEltsToInit = NumElts;

DEBUG(llvm::dbgs() << "The number of elements to initialize: " <<do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("exprconstant")) { llvm::dbgs() << "The number of elements to initialize: "
 << NumEltsToInit << ".\n"; } } while (false)
      NumEltsToInit << ".\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("exprconstant")) { llvm::dbgs() << "The number of elements to initialize: "
 << NumEltsToInit << ".\n"; } } while (false);

Result = APValue(APValue::UninitArray(), NumEltsToInit, NumElts);

// If the array was previously zero-initialized, preserve the
// zero-initialized values.
if (!Filler.isUninit()) {
  for (unsigned I = 0, E = Result.getArrayInitializedElts(); I != E; ++I)
    Result.getArrayInitializedElt(I) = Filler;
  if (Result.hasArrayFiller())
    Result.getArrayFiller() = Filler;
}

LValue Subobject = This;
Subobject.addArray(Info, E, CAT);
for (unsigned Index = 0; Index != NumEltsToInit; ++Index) {
  const Expr *Init =
      Index < E->getNumInits() ? E->getInit(Index) : FillerExpr;
  if (!EvaluateInPlace(Result.getArrayInitializedElt(Index),
                       Info, Subobject, Init) ||
      !HandleLValueArrayAdjustment(Info, Init, Subobject,
                                   CAT->getElementType(), 1)) {
    if (!Info.noteFailure())
      return false;
    Success = false;
  }
}

if (!Result.hasArrayFiller())
  return Success;

// If we get here, we have a trivial filler, which we can just evaluate
// once and splat over the rest of the array elements.
assert(FillerExpr && "no array filler for incomplete init list")(static_cast <bool> (FillerExpr && "no array filler for incomplete init list"
) ? void (0) : __assert_fail ("FillerExpr && \"no array filler for incomplete init list\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 6892, __extension__ __PRETTY_FUNCTION__));
return EvaluateInPlace(Result.getArrayFiller(), Info, Subobject,
                       FillerExpr) && Success;
6895}

6897bool ArrayExprEvaluator::VisitArrayInitLoopExpr(const ArrayInitLoopExpr *E) {
if (E->getCommonExpr() &&
    !Evaluate(Info.CurrentCall->createTemporary(E->getCommonExpr(), false),
              Info, E->getCommonExpr()->getSourceExpr()))
  return false;

auto *CAT = cast<ConstantArrayType>(E->getType()->castAsArrayTypeUnsafe());

uint64_t Elements = CAT->getSize().getZExtValue();
Result = APValue(APValue::UninitArray(), Elements, Elements);

LValue Subobject = This;
Subobject.addArray(Info, E, CAT);

bool Success = true;
for (EvalInfo::ArrayInitLoopIndex Index(Info); Index != Elements; ++Index) {
  if (!EvaluateInPlace(Result.getArrayInitializedElt(Index),
                       Info, Subobject, E->getSubExpr()) ||
      !HandleLValueArrayAdjustment(Info, E, Subobject,
                                   CAT->getElementType(), 1)) {
    if (!Info.noteFailure())
      return false;
    Success = false;
  }
}

return Success;
6924}

6926bool ArrayExprEvaluator::VisitCXXConstructExpr(const CXXConstructExpr *E) {
return VisitCXXConstructExpr(E, This, &Result, E->getType());
6928}

6930bool ArrayExprEvaluator::VisitCXXConstructExpr(const CXXConstructExpr *E,
                                             const LValue &Subobject,
                                             APValue *Value,
                                             QualType Type) {
bool HadZeroInit = !Value->isUninit();

if (const ConstantArrayType *CAT = Info.Ctx.getAsConstantArrayType(Type)) {
  unsigned N = CAT->getSize().getZExtValue();

  // Preserve the array filler if we had prior zero-initialization.
  APValue Filler =
    HadZeroInit && Value->hasArrayFiller() ? Value->getArrayFiller()
                                           : APValue();

  *Value = APValue(APValue::UninitArray(), N, N);

  if (HadZeroInit)
    for (unsigned I = 0; I != N; ++I)
      Value->getArrayInitializedElt(I) = Filler;

  // Initialize the elements.
  LValue ArrayElt = Subobject;
  ArrayElt.addArray(Info, E, CAT);
  for (unsigned I = 0; I != N; ++I)
    if (!VisitCXXConstructExpr(E, ArrayElt, &Value->getArrayInitializedElt(I),
                               CAT->getElementType()) ||
        !HandleLValueArrayAdjustment(Info, E, ArrayElt,
                                     CAT->getElementType(), 1))
      return false;

  return true;
}

if (!Type->isRecordType())
  return Error(E);

return RecordExprEvaluator(Info, Subobject, *Value)
           .VisitCXXConstructExpr(E, Type);
6968}

6970//===----------------------------------------------------------------------===//
6971// Integer Evaluation
6972//
6973// As a GNU extension, we support casting pointers to sufficiently-wide integer
6974// types and back in constant folding. Integer values are thus represented
6975// either as an integer-valued APValue, or as an lvalue-valued APValue.
6976//===----------------------------------------------------------------------===//

6978namespace {
6979class IntExprEvaluator
: public ExprEvaluatorBase<IntExprEvaluator> {
APValue &Result;
6982public:
IntExprEvaluator(EvalInfo &info, APValue &result)
  : ExprEvaluatorBaseTy(info), Result(result) {}

bool Success(const llvm::APSInt &SI, const Expr *E, APValue &Result) {
  assert(E->getType()->isIntegralOrEnumerationType() &&(static_cast <bool> (E->getType()->isIntegralOrEnumerationType
() && "Invalid evaluation result.") ? void (0) : __assert_fail
 ("E->getType()->isIntegralOrEnumerationType() && \"Invalid evaluation result.\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 6988, __extension__ __PRETTY_FUNCTION__))
         "Invalid evaluation result.")(static_cast <bool> (E->getType()->isIntegralOrEnumerationType
() && "Invalid evaluation result.") ? void (0) : __assert_fail
 ("E->getType()->isIntegralOrEnumerationType() && \"Invalid evaluation result.\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 6988, __extension__ __PRETTY_FUNCTION__));
  assert(SI.isSigned() == E->getType()->isSignedIntegerOrEnumerationType() &&(static_cast <bool> (SI.isSigned() == E->getType()->
isSignedIntegerOrEnumerationType() && "Invalid evaluation result."
) ? void (0) : __assert_fail ("SI.isSigned() == E->getType()->isSignedIntegerOrEnumerationType() && \"Invalid evaluation result.\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 6990, __extension__ __PRETTY_FUNCTION__))
         "Invalid evaluation result.")(static_cast <bool> (SI.isSigned() == E->getType()->
isSignedIntegerOrEnumerationType() && "Invalid evaluation result."
) ? void (0) : __assert_fail ("SI.isSigned() == E->getType()->isSignedIntegerOrEnumerationType() && \"Invalid evaluation result.\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 6990, __extension__ __PRETTY_FUNCTION__));
  assert(SI.getBitWidth() == Info.Ctx.getIntWidth(E->getType()) &&(static_cast <bool> (SI.getBitWidth() == Info.Ctx.getIntWidth
(E->getType()) && "Invalid evaluation result.") ? void
 (0) : __assert_fail ("SI.getBitWidth() == Info.Ctx.getIntWidth(E->getType()) && \"Invalid evaluation result.\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 6992, __extension__ __PRETTY_FUNCTION__))
         "Invalid evaluation result.")(static_cast <bool> (SI.getBitWidth() == Info.Ctx.getIntWidth
(E->getType()) && "Invalid evaluation result.") ? void
 (0) : __assert_fail ("SI.getBitWidth() == Info.Ctx.getIntWidth(E->getType()) && \"Invalid evaluation result.\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 6992, __extension__ __PRETTY_FUNCTION__));
  Result = APValue(SI);
  return true;
}
bool Success(const llvm::APSInt &SI, const Expr *E) {
  return Success(SI, E, Result);
}

bool Success(const llvm::APInt &I, const Expr *E, APValue &Result) {
  assert(E->getType()->isIntegralOrEnumerationType() &&(static_cast <bool> (E->getType()->isIntegralOrEnumerationType
() && "Invalid evaluation result.") ? void (0) : __assert_fail
 ("E->getType()->isIntegralOrEnumerationType() && \"Invalid evaluation result.\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 7002, __extension__ __PRETTY_FUNCTION__)) 
         "Invalid evaluation result.")(static_cast <bool> (E->getType()->isIntegralOrEnumerationType
() && "Invalid evaluation result.") ? void (0) : __assert_fail
 ("E->getType()->isIntegralOrEnumerationType() && \"Invalid evaluation result.\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 7002, __extension__ __PRETTY_FUNCTION__));
  assert(I.getBitWidth() == Info.Ctx.getIntWidth(E->getType()) &&(static_cast <bool> (I.getBitWidth() == Info.Ctx.getIntWidth
(E->getType()) && "Invalid evaluation result.") ? void
 (0) : __assert_fail ("I.getBitWidth() == Info.Ctx.getIntWidth(E->getType()) && \"Invalid evaluation result.\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 7004, __extension__ __PRETTY_FUNCTION__))
         "Invalid evaluation result.")(static_cast <bool> (I.getBitWidth() == Info.Ctx.getIntWidth
(E->getType()) && "Invalid evaluation result.") ? void
 (0) : __assert_fail ("I.getBitWidth() == Info.Ctx.getIntWidth(E->getType()) && \"Invalid evaluation result.\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 7004, __extension__ __PRETTY_FUNCTION__));
  Result = APValue(APSInt(I));
  Result.getInt().setIsUnsigned(
                          E->getType()->isUnsignedIntegerOrEnumerationType());
  return true;
}
bool Success(const llvm::APInt &I, const Expr *E) {
  return Success(I, E, Result);
}

bool Success(uint64_t Value, const Expr *E, APValue &Result) {
  assert(E->getType()->isIntegralOrEnumerationType() &&(static_cast <bool> (E->getType()->isIntegralOrEnumerationType
() && "Invalid evaluation result.") ? void (0) : __assert_fail
 ("E->getType()->isIntegralOrEnumerationType() && \"Invalid evaluation result.\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 7016, __extension__ __PRETTY_FUNCTION__)) 
         "Invalid evaluation result.")(static_cast <bool> (E->getType()->isIntegralOrEnumerationType
() && "Invalid evaluation result.") ? void (0) : __assert_fail
 ("E->getType()->isIntegralOrEnumerationType() && \"Invalid evaluation result.\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 7016, __extension__ __PRETTY_FUNCTION__));
  Result = APValue(Info.Ctx.MakeIntValue(Value, E->getType()));
  return true;
}
bool Success(uint64_t Value, const Expr *E) {
  return Success(Value, E, Result);
}

bool Success(CharUnits Size, const Expr *E) {
  return Success(Size.getQuantity(), E);
}

bool Success(const APValue &V, const Expr *E) {
  if (V.isLValue() || V.isAddrLabelDiff()) {
    Result = V;
    return true;
  }
  return Success(V.getInt(), E);
}

bool ZeroInitialization(const Expr *E) { return Success(0, E); }

//===--------------------------------------------------------------------===//
//                            Visitor Methods
//===--------------------------------------------------------------------===//

bool VisitIntegerLiteral(const IntegerLiteral *E) {
  return Success(E->getValue(), E);
}
bool VisitCharacterLiteral(const CharacterLiteral *E) {
  return Success(E->getValue(), E);
}

bool CheckReferencedDecl(const Expr *E, const Decl *D);
bool VisitDeclRefExpr(const DeclRefExpr *E) {
  if (CheckReferencedDecl(E, E->getDecl()))
    return true;

  return ExprEvaluatorBaseTy::VisitDeclRefExpr(E);
}
bool VisitMemberExpr(const MemberExpr *E) {
  if (CheckReferencedDecl(E, E->getMemberDecl())) {
    VisitIgnoredBaseExpression(E->getBase());
    return true;
  }

  return ExprEvaluatorBaseTy::VisitMemberExpr(E);
}

bool VisitCallExpr(const CallExpr *E);
bool VisitBuiltinCallExpr(const CallExpr *E, unsigned BuiltinOp);
bool VisitBinaryOperator(const BinaryOperator *E);
bool VisitOffsetOfExpr(const OffsetOfExpr *E);
bool VisitUnaryOperator(const UnaryOperator *E);

bool VisitCastExpr(const CastExpr* E);
bool VisitUnaryExprOrTypeTraitExpr(const UnaryExprOrTypeTraitExpr *E);

bool VisitCXXBoolLiteralExpr(const CXXBoolLiteralExpr *E) {
  return Success(E->getValue(), E);
}

bool VisitObjCBoolLiteralExpr(const ObjCBoolLiteralExpr *E) {
  return Success(E->getValue(), E);
}

bool VisitArrayInitIndexExpr(const ArrayInitIndexExpr *E) {
  if (Info.ArrayInitIndex == uint64_t(-1)) {
    // We were asked to evaluate this subexpression independent of the
    // enclosing ArrayInitLoopExpr. We can't do that.
    Info.FFDiag(E);
    return false;
  }
  return Success(Info.ArrayInitIndex, E);
}
  
// Note, GNU defines __null as an integer, not a pointer.
bool VisitGNUNullExpr(const GNUNullExpr *E) {
  return ZeroInitialization(E);
}

bool VisitTypeTraitExpr(const TypeTraitExpr *E) {
  return Success(E->getValue(), E);
}

bool VisitArrayTypeTraitExpr(const ArrayTypeTraitExpr *E) {
  return Success(E->getValue(), E);
}

bool VisitExpressionTraitExpr(const ExpressionTraitExpr *E) {
  return Success(E->getValue(), E);
}

bool VisitUnaryReal(const UnaryOperator *E);
bool VisitUnaryImag(const UnaryOperator *E);

bool VisitCXXNoexceptExpr(const CXXNoexceptExpr *E);
bool VisitSizeOfPackExpr(const SizeOfPackExpr *E);

// FIXME: Missing: array subscript of vector, member of vector
7116};
7117} // end anonymous namespace

7119/// EvaluateIntegerOrLValue - Evaluate an rvalue integral-typed expression, and
7120/// produce either the integer value or a pointer.
7121///
7122/// GCC has a heinous extension which folds casts between pointer types and
7123/// pointer-sized integral types. We support this by allowing the evaluation of
7124/// an integer rvalue to produce a pointer (represented as an lvalue) instead.
7125/// Some simple arithmetic on such values is supported (they are treated much
7126/// like char*).
7127static bool EvaluateIntegerOrLValue(const Expr *E, APValue &Result,
                                  EvalInfo &Info) {
assert(E->isRValue() && E->getType()->isIntegralOrEnumerationType())(static_cast <bool> (E->isRValue() && E->
getType()->isIntegralOrEnumerationType()) ? void (0) : __assert_fail
 ("E->isRValue() && E->getType()->isIntegralOrEnumerationType()"
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 7129, __extension__ __PRETTY_FUNCTION__));
return IntExprEvaluator(Info, Result).Visit(E);
7131}

7133static bool EvaluateInteger(const Expr *E, APSInt &Result, EvalInfo &Info) {
APValue Val;
if (!EvaluateIntegerOrLValue(E, Val, Info))
  return false;
if (!Val.isInt()) {
  // FIXME: It would be better to produce the diagnostic for casting
  //        a pointer to an integer.
  Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr);
  return false;
}
Result = Val.getInt();
return true;
7145}

7147/// Check whether the given declaration can be directly converted to an integral
7148/// rvalue. If not, no diagnostic is produced; there are other things we can
7149/// try.
7150bool IntExprEvaluator::CheckReferencedDecl(const Expr* E, const Decl* D) {
// Enums are integer constant exprs.
if (const EnumConstantDecl *ECD = dyn_cast<EnumConstantDecl>(D)) {
  // Check for signedness/width mismatches between E type and ECD value.
  bool SameSign = (ECD->getInitVal().isSigned()
                   == E->getType()->isSignedIntegerOrEnumerationType());
  bool SameWidth = (ECD->getInitVal().getBitWidth()
                    == Info.Ctx.getIntWidth(E->getType()));
  if (SameSign && SameWidth)
    return Success(ECD->getInitVal(), E);
  else {
    // Get rid of mismatch (otherwise Success assertions will fail)
    // by computing a new value matching the type of E.
    llvm::APSInt Val = ECD->getInitVal();
    if (!SameSign)
      Val.setIsSigned(!ECD->getInitVal().isSigned());
    if (!SameWidth)
      Val = Val.extOrTrunc(Info.Ctx.getIntWidth(E->getType()));
    return Success(Val, E);
  }
}
return false;
7172}

7174/// EvaluateBuiltinClassifyType - Evaluate __builtin_classify_type the same way
7175/// as GCC.
7176static int EvaluateBuiltinClassifyType(const CallExpr *E,
                                     const LangOptions &LangOpts) {
// The following enum mimics the values returned by GCC.
// FIXME: Does GCC differ between lvalue and rvalue references here?
enum gcc_type_class {
  no_type_class = -1,
  void_type_class, integer_type_class, char_type_class,
  enumeral_type_class, boolean_type_class,
  pointer_type_class, reference_type_class, offset_type_class,
  real_type_class, complex_type_class,
  function_type_class, method_type_class,
  record_type_class, union_type_class,
  array_type_class, string_type_class,
  lang_type_class
};

// If no argument was supplied, default to "no_type_class". This isn't
// ideal, however it is what gcc does.
if (E->getNumArgs() == 0)
  return no_type_class;

QualType CanTy = E->getArg(0)->getType().getCanonicalType();
const BuiltinType *BT = dyn_cast<BuiltinType>(CanTy);

switch (CanTy->getTypeClass()) {
7201#define TYPE(ID, BASE)
7202#define DEPENDENT_TYPE(ID, BASE) case Type::ID:
7203#define NON_CANONICAL_TYPE(ID, BASE) case Type::ID:
7204#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(ID, BASE) case Type::ID:
7205#include "clang/AST/TypeNodes.def"
    llvm_unreachable("CallExpr::isBuiltinClassifyType(): unimplemented type")::llvm::llvm_unreachable_internal("CallExpr::isBuiltinClassifyType(): unimplemented type"
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 7206);

case Type::Builtin:
  switch (BT->getKind()) {
7210#define BUILTIN_TYPE(ID, SINGLETON_ID)
7211#define SIGNED_TYPE(ID, SINGLETON_ID) case BuiltinType::ID: return integer_type_class;
7212#define FLOATING_TYPE(ID, SINGLETON_ID) case BuiltinType::ID: return real_type_class;
7213#define PLACEHOLDER_TYPE(ID, SINGLETON_ID) case BuiltinType::ID: break;
7214#include "clang/AST/BuiltinTypes.def"
  case BuiltinType::Void:
    return void_type_class;

  case BuiltinType::Bool:
    return boolean_type_class;

  case BuiltinType::Char_U: // gcc doesn't appear to use char_type_class
  case BuiltinType::UChar:
  case BuiltinType::UShort:
  case BuiltinType::UInt:
  case BuiltinType::ULong:
  case BuiltinType::ULongLong:
  case BuiltinType::UInt128:
    return integer_type_class;

  case BuiltinType::NullPtr:
    return pointer_type_class;

  case BuiltinType::WChar_U:
  case BuiltinType::Char16:
  case BuiltinType::Char32:
  case BuiltinType::ObjCId:
  case BuiltinType::ObjCClass:
  case BuiltinType::ObjCSel:
7239#define IMAGE_TYPE(ImgType, Id, SingletonId, Access, Suffix) \
  case BuiltinType::Id:
7241#include "clang/Basic/OpenCLImageTypes.def"
  case BuiltinType::OCLSampler:
  case BuiltinType::OCLEvent:
  case BuiltinType::OCLClkEvent:
  case BuiltinType::OCLQueue:
  case BuiltinType::OCLReserveID:
  case BuiltinType::Dependent:
    llvm_unreachable("CallExpr::isBuiltinClassifyType(): unimplemented type")::llvm::llvm_unreachable_internal("CallExpr::isBuiltinClassifyType(): unimplemented type"
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 7248);
  };
  break;

case Type::Enum:
  return LangOpts.CPlusPlus ? enumeral_type_class : integer_type_class;
  break;

case Type::Pointer:
  return pointer_type_class;
  break;

case Type::MemberPointer:
  if (CanTy->isMemberDataPointerType())
    return offset_type_class;
  else {
    // We expect member pointers to be either data or function pointers,
    // nothing else.
    assert(CanTy->isMemberFunctionPointerType())(static_cast <bool> (CanTy->isMemberFunctionPointerType
()) ? void (0) : __assert_fail ("CanTy->isMemberFunctionPointerType()"
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 7266, __extension__ __PRETTY_FUNCTION__));
    return method_type_class;
  }

case Type::Complex:
  return complex_type_class;

case Type::FunctionNoProto:
case Type::FunctionProto:
  return LangOpts.CPlusPlus ? function_type_class : pointer_type_class;

case Type::Record:
  if (const RecordType *RT = CanTy->getAs<RecordType>()) {
    switch (RT->getDecl()->getTagKind()) {
    case TagTypeKind::TTK_Struct:
    case TagTypeKind::TTK_Class:
    case TagTypeKind::TTK_Interface:
      return record_type_class;

    case TagTypeKind::TTK_Enum:
      return LangOpts.CPlusPlus ? enumeral_type_class : integer_type_class;

    case TagTypeKind::TTK_Union:
      return union_type_class;
    }
  }
  llvm_unreachable("CallExpr::isBuiltinClassifyType(): unimplemented type")::llvm::llvm_unreachable_internal("CallExpr::isBuiltinClassifyType(): unimplemented type"
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 7292);

case Type::ConstantArray:
case Type::VariableArray:
case Type::IncompleteArray:
  return LangOpts.CPlusPlus ? array_type_class : pointer_type_class;

case Type::BlockPointer:
case Type::LValueReference:
case Type::RValueReference:
case Type::Vector:
case Type::ExtVector:
case Type::Auto:
case Type::DeducedTemplateSpecialization:
case Type::ObjCObject:
case Type::ObjCInterface:
case Type::ObjCObjectPointer:
case Type::Pipe:
case Type::Atomic:
  llvm_unreachable("CallExpr::isBuiltinClassifyType(): unimplemented type")::llvm::llvm_unreachable_internal("CallExpr::isBuiltinClassifyType(): unimplemented type"
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 7311);
}

llvm_unreachable("CallExpr::isBuiltinClassifyType(): unimplemented type")::llvm::llvm_unreachable_internal("CallExpr::isBuiltinClassifyType(): unimplemented type"
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 7314);
7315}

7317/// EvaluateBuiltinConstantPForLValue - Determine the result of
7318/// __builtin_constant_p when applied to the given lvalue.
7319///
7320/// An lvalue is only "constant" if it is a pointer or reference to the first
7321/// character of a string literal.
7322template<typename LValue>
7323static bool EvaluateBuiltinConstantPForLValue(const LValue &LV) {
const Expr *E = LV.getLValueBase().template dyn_cast<const Expr*>();
return E && isa<StringLiteral>(E) && LV.getLValueOffset().isZero();
7326}

7328/// EvaluateBuiltinConstantP - Evaluate __builtin_constant_p as similarly to
7329/// GCC as we can manage.
7330static bool EvaluateBuiltinConstantP(ASTContext &Ctx, const Expr *Arg) {
QualType ArgType = Arg->getType();

// __builtin_constant_p always has one operand. The rules which gcc follows
// are not precisely documented, but are as follows:
//
//  - If the operand is of integral, floating, complex or enumeration type,
//    and can be folded to a known value of that type, it returns 1.
//  - If the operand and can be folded to a pointer to the first character
//    of a string literal (or such a pointer cast to an integral type), it
//    returns 1.
//
// Otherwise, it returns 0.
//
// FIXME: GCC also intends to return 1 for literals of aggregate types, but
// its support for this does not currently work.
if (ArgType->isIntegralOrEnumerationType()) {
  Expr::EvalResult Result;
  if (!Arg->EvaluateAsRValue(Result, Ctx) || Result.HasSideEffects)
    return false;

  APValue &V = Result.Val;
  if (V.getKind() == APValue::Int)
    return true;
  if (V.getKind() == APValue::LValue)
    return EvaluateBuiltinConstantPForLValue(V);
} else if (ArgType->isFloatingType() || ArgType->isAnyComplexType()) {
  return Arg->isEvaluatable(Ctx);
} else if (ArgType->isPointerType() || Arg->isGLValue()) {
  LValue LV;
  Expr::EvalStatus Status;
  EvalInfo Info(Ctx, Status, EvalInfo::EM_ConstantFold);
  if ((Arg->isGLValue() ? EvaluateLValue(Arg, LV, Info)
                        : EvaluatePointer(Arg, LV, Info)) &&
      !Status.HasSideEffects)
    return EvaluateBuiltinConstantPForLValue(LV);
}

// Anything else isn't considered to be sufficiently constant.
return false;
7370}

7372/// Retrieves the "underlying object type" of the given expression,
7373/// as used by __builtin_object_size.
7374static QualType getObjectType(APValue::LValueBase B) {
if (const ValueDecl *D = B.dyn_cast<const ValueDecl*>()) {
  if (const VarDecl *VD = dyn_cast<VarDecl>(D))
    return VD->getType();
} else if (const Expr *E = B.get<const Expr*>()) {
  if (isa<CompoundLiteralExpr>(E))
    return E->getType();
}

return QualType();
7384}

7386/// A more selective version of E->IgnoreParenCasts for
7387/// tryEvaluateBuiltinObjectSize. This ignores some casts/parens that serve only
7388/// to change the type of E.
7389/// Ex. For E = `(short*)((char*)(&foo))`, returns `&foo`
7390///
7391/// Always returns an RValue with a pointer representation.
7392static const Expr *ignorePointerCastsAndParens(const Expr *E) {
assert(E->isRValue() && E->getType()->hasPointerRepresentation())(static_cast <bool> (E->isRValue() && E->
getType()->hasPointerRepresentation()) ? void (0) : __assert_fail
 ("E->isRValue() && E->getType()->hasPointerRepresentation()"
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 7393, __extension__ __PRETTY_FUNCTION__));

auto *NoParens = E->IgnoreParens();
auto *Cast = dyn_cast<CastExpr>(NoParens);
if (Cast == nullptr)
  return NoParens;

// We only conservatively allow a few kinds of casts, because this code is
// inherently a simple solution that seeks to support the common case.
auto CastKind = Cast->getCastKind();
if (CastKind != CK_NoOp && CastKind != CK_BitCast &&
    CastKind != CK_AddressSpaceConversion)
  return NoParens;

auto *SubExpr = Cast->getSubExpr();
if (!SubExpr->getType()->hasPointerRepresentation() || !SubExpr->isRValue())
  return NoParens;
return ignorePointerCastsAndParens(SubExpr);
7411}

7413/// Checks to see if the given LValue's Designator is at the end of the LValue's
7414/// record layout. e.g.
7415///   struct { struct { int a, b; } fst, snd; } obj;
7416///   obj.fst   // no
7417///   obj.snd   // yes
7418///   obj.fst.a // no
7419///   obj.fst.b // no
7420///   obj.snd.a // no
7421///   obj.snd.b // yes
7422///
7423/// Please note: this function is specialized for how __builtin_object_size
7424/// views "objects".
7425///
7426/// If this encounters an invalid RecordDecl or otherwise cannot determine the
7427/// correct result, it will always return true.
7428static bool isDesignatorAtObjectEnd(const ASTContext &Ctx, const LValue &LVal) {
assert(!LVal.Designator.Invalid)(static_cast <bool> (!LVal.Designator.Invalid) ? void (
0) : __assert_fail ("!LVal.Designator.Invalid", "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 7429, __extension__ __PRETTY_FUNCTION__));

auto IsLastOrInvalidFieldDecl = [&Ctx](const FieldDecl *FD, bool &Invalid) {
  const RecordDecl *Parent = FD->getParent();
  Invalid = Parent->isInvalidDecl();
  if (Invalid || Parent->isUnion())
    return true;
  const ASTRecordLayout &Layout = Ctx.getASTRecordLayout(Parent);
  return FD->getFieldIndex() + 1 == Layout.getFieldCount();
};

auto &Base = LVal.getLValueBase();
if (auto *ME = dyn_cast_or_null<MemberExpr>(Base.dyn_cast<const Expr *>())) {
  if (auto *FD = dyn_cast<FieldDecl>(ME->getMemberDecl())) {
    bool Invalid;
    if (!IsLastOrInvalidFieldDecl(FD, Invalid))
      return Invalid;
  } else if (auto *IFD = dyn_cast<IndirectFieldDecl>(ME->getMemberDecl())) {
    for (auto *FD : IFD->chain()) {
      bool Invalid;
      if (!IsLastOrInvalidFieldDecl(cast<FieldDecl>(FD), Invalid))
        return Invalid;
    }
  }
}

unsigned I = 0;
QualType BaseType = getType(Base);
if (LVal.Designator.FirstEntryIsAnUnsizedArray) {
  // If we don't know the array bound, conservatively assume we're looking at
  // the final array element.
  ++I;
  if (BaseType->isIncompleteArrayType())
    BaseType = Ctx.getAsArrayType(BaseType)->getElementType();
  else
    BaseType = BaseType->castAs<PointerType>()->getPointeeType();
}

for (unsigned E = LVal.Designator.Entries.size(); I != E; ++I) {
  const auto &Entry = LVal.Designator.Entries[I];
  if (BaseType->isArrayType()) {
    // Because __builtin_object_size treats arrays as objects, we can ignore
    // the index iff this is the last array in the Designator.
    if (I + 1 == E)
      return true;
    const auto *CAT = cast<ConstantArrayType>(Ctx.getAsArrayType(BaseType));
    uint64_t Index = Entry.ArrayIndex;
    if (Index + 1 != CAT->getSize())
      return false;
    BaseType = CAT->getElementType();
  } else if (BaseType->isAnyComplexType()) {
    const auto *CT = BaseType->castAs<ComplexType>();
    uint64_t Index = Entry.ArrayIndex;
    if (Index != 1)
      return false;
    BaseType = CT->getElementType();
  } else if (auto *FD = getAsField(Entry)) {
    bool Invalid;
    if (!IsLastOrInvalidFieldDecl(FD, Invalid))
      return Invalid;
    BaseType = FD->getType();
  } else {
    assert(getAsBaseClass(Entry) && "Expecting cast to a base class")(static_cast <bool> (getAsBaseClass(Entry) && "Expecting cast to a base class"
) ? void (0) : __assert_fail ("getAsBaseClass(Entry) && \"Expecting cast to a base class\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 7491, __extension__ __PRETTY_FUNCTION__));
    return false;
  }
}
return true;
7496}

7498/// Tests to see if the LValue has a user-specified designator (that isn't
7499/// necessarily valid). Note that this always returns 'true' if the LValue has
7500/// an unsized array as its first designator entry, because there's currently no
7501/// way to tell if the user typed *foo or foo[0].
7502static bool refersToCompleteObject(const LValue &LVal) {
if (LVal.Designator.Invalid)
  return false;

if (!LVal.Designator.Entries.empty())
  return LVal.Designator.isMostDerivedAnUnsizedArray();

if (!LVal.InvalidBase)
  return true;

// If `E` is a MemberExpr, then the first part of the designator is hiding in
// the LValueBase.
const auto *E = LVal.Base.dyn_cast<const Expr *>();
return !E || !isa<MemberExpr>(E);
7516}

7518/// Attempts to detect a user writing into a piece of memory that's impossible
7519/// to figure out the size of by just using types.
7520static bool isUserWritingOffTheEnd(const ASTContext &Ctx, const LValue &LVal) {
const SubobjectDesignator &Designator = LVal.Designator;
// Notes:
// - Users can only write off of the end when we have an invalid base. Invalid
//   bases imply we don't know where the memory came from.
// - We used to be a bit more aggressive here; we'd only be conservative if
//   the array at the end was flexible, or if it had 0 or 1 elements. This
//   broke some common standard library extensions (PR30346), but was
//   otherwise seemingly fine. It may be useful to reintroduce this behavior
//   with some sort of whitelist. OTOH, it seems that GCC is always
//   conservative with the last element in structs (if it's an array), so our
//   current behavior is more compatible than a whitelisting approach would
//   be.
return LVal.InvalidBase &&
       Designator.Entries.size() == Designator.MostDerivedPathLength &&
       Designator.MostDerivedIsArrayElement &&
       isDesignatorAtObjectEnd(Ctx, LVal);
7537}

7539/// Converts the given APInt to CharUnits, assuming the APInt is unsigned.
7540/// Fails if the conversion would cause loss of precision.
7541static bool convertUnsignedAPIntToCharUnits(const llvm::APInt &Int,
                                          CharUnits &Result) {
auto CharUnitsMax = std::numeric_limits<CharUnits::QuantityType>::max();
if (Int.ugt(CharUnitsMax))
  return false;
Result = CharUnits::fromQuantity(Int.getZExtValue());
return true;
7548}

7550/// Helper for tryEvaluateBuiltinObjectSize -- Given an LValue, this will
7551/// determine how many bytes exist from the beginning of the object to either
7552/// the end of the current subobject, or the end of the object itself, depending
7553/// on what the LValue looks like + the value of Type.
7554///
7555/// If this returns false, the value of Result is undefined.
7556static bool determineEndOffset(EvalInfo &Info, SourceLocation ExprLoc,
                             unsigned Type, const LValue &LVal,
                             CharUnits &EndOffset) {
bool DetermineForCompleteObject = refersToCompleteObject(LVal);

auto CheckedHandleSizeof = [&](QualType Ty, CharUnits &Result) {
  if (Ty.isNull() || Ty->isIncompleteType() || Ty->isFunctionType())
    return false;
  return HandleSizeof(Info, ExprLoc, Ty, Result);
};

// We want to evaluate the size of the entire object. This is a valid fallback
// for when Type=1 and the designator is invalid, because we're asked for an
// upper-bound.
if (!(Type & 1) || LVal.Designator.Invalid || DetermineForCompleteObject) {
  // Type=3 wants a lower bound, so we can't fall back to this.
  if (Type == 3 && !DetermineForCompleteObject)
    return false;

  llvm::APInt APEndOffset;
  if (isBaseAnAllocSizeCall(LVal.getLValueBase()) &&
      getBytesReturnedByAllocSizeCall(Info.Ctx, LVal, APEndOffset))
    return convertUnsignedAPIntToCharUnits(APEndOffset, EndOffset);

  if (LVal.InvalidBase)
    return false;

  QualType BaseTy = getObjectType(LVal.getLValueBase());
  return CheckedHandleSizeof(BaseTy, EndOffset);
}

// We want to evaluate the size of a subobject.
const SubobjectDesignator &Designator = LVal.Designator;

// The following is a moderately common idiom in C:
//
// struct Foo { int a; char c[1]; };
// struct Foo *F = (struct Foo *)malloc(sizeof(struct Foo) + strlen(Bar));
// strcpy(&F->c[0], Bar);
//
// In order to not break too much legacy code, we need to support it.
if (isUserWritingOffTheEnd(Info.Ctx, LVal)) {
  // If we can resolve this to an alloc_size call, we can hand that back,
  // because we know for certain how many bytes there are to write to.
  llvm::APInt APEndOffset;
  if (isBaseAnAllocSizeCall(LVal.getLValueBase()) &&
      getBytesReturnedByAllocSizeCall(Info.Ctx, LVal, APEndOffset))
    return convertUnsignedAPIntToCharUnits(APEndOffset, EndOffset);

  // If we cannot determine the size of the initial allocation, then we can't
  // given an accurate upper-bound. However, we are still able to give
  // conservative lower-bounds for Type=3.
  if (Type == 1)
    return false;
}

CharUnits BytesPerElem;
if (!CheckedHandleSizeof(Designator.MostDerivedType, BytesPerElem))
  return false;

// According to the GCC documentation, we want the size of the subobject
// denoted by the pointer. But that's not quite right -- what we actually
// want is the size of the immediately-enclosing array, if there is one.
int64_t ElemsRemaining;
if (Designator.MostDerivedIsArrayElement &&
    Designator.Entries.size() == Designator.MostDerivedPathLength) {
  uint64_t ArraySize = Designator.getMostDerivedArraySize();
  uint64_t ArrayIndex = Designator.Entries.back().ArrayIndex;
  ElemsRemaining = ArraySize <= ArrayIndex ? 0 : ArraySize - ArrayIndex;
} else {
  ElemsRemaining = Designator.isOnePastTheEnd() ? 0 : 1;
}

EndOffset = LVal.getLValueOffset() + BytesPerElem * ElemsRemaining;
return true;
7631}

7633/// \brief Tries to evaluate the __builtin_object_size for @p E. If successful,
7634/// returns true and stores the result in @p Size.
7635///
7636/// If @p WasError is non-null, this will report whether the failure to evaluate
7637/// is to be treated as an Error in IntExprEvaluator.
7638static bool tryEvaluateBuiltinObjectSize(const Expr *E, unsigned Type,
                                       EvalInfo &Info, uint64_t &Size) {
// Determine the denoted object.
LValue LVal;
{
  // The operand of __builtin_object_size is never evaluated for side-effects.
  // If there are any, but we can determine the pointed-to object anyway, then
  // ignore the side-effects.
  SpeculativeEvaluationRAII SpeculativeEval(Info);
  FoldOffsetRAII Fold(Info);

  if (E->isGLValue()) {
    // It's possible for us to be given GLValues if we're called via
    // Expr::tryEvaluateObjectSize.
    APValue RVal;
    if (!EvaluateAsRValue(Info, E, RVal))
      return false;
    LVal.setFrom(Info.Ctx, RVal);
  } else if (!EvaluatePointer(ignorePointerCastsAndParens(E), LVal, Info,
                              /*InvalidBaseOK=*/true))
    return false;
}

// If we point to before the start of the object, there are no accessible
// bytes.
if (LVal.getLValueOffset().isNegative()) {
  Size = 0;
  return true;
}

CharUnits EndOffset;
if (!determineEndOffset(Info, E->getExprLoc(), Type, LVal, EndOffset))
  return false;

// If we've fallen outside of the end offset, just pretend there's nothing to
// write to/read from.
if (EndOffset <= LVal.getLValueOffset())
  Size = 0;
else
  Size = (EndOffset - LVal.getLValueOffset()).getQuantity();
return true;
7679}

7681bool IntExprEvaluator::VisitCallExpr(const CallExpr *E) {
if (unsigned BuiltinOp = E->getBuiltinCallee())
  return VisitBuiltinCallExpr(E, BuiltinOp);

return ExprEvaluatorBaseTy::VisitCallExpr(E);
7686}

7688bool IntExprEvaluator::VisitBuiltinCallExpr(const CallExpr *E,
                                          unsigned BuiltinOp) {
switch (unsigned BuiltinOp = E->getBuiltinCallee()) {
default:
  return ExprEvaluatorBaseTy::VisitCallExpr(E);

case Builtin::BI__builtin_object_size: {
  // The type was checked when we built the expression.
  unsigned Type =
      E->getArg(1)->EvaluateKnownConstInt(Info.Ctx).getZExtValue();
  assert(Type <= 3 && "unexpected type")(static_cast <bool> (Type <= 3 && "unexpected type"
) ? void (0) : __assert_fail ("Type <= 3 && \"unexpected type\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 7698, __extension__ __PRETTY_FUNCTION__));

  uint64_t Size;
  if (tryEvaluateBuiltinObjectSize(E->getArg(0), Type, Info, Size))
    return Success(Size, E);

  if (E->getArg(0)->HasSideEffects(Info.Ctx))
    return Success((Type & 2) ? 0 : -1, E);

  // Expression had no side effects, but we couldn't statically determine the
  // size of the referenced object.
  switch (Info.EvalMode) {
  case EvalInfo::EM_ConstantExpression:
  case EvalInfo::EM_PotentialConstantExpression:
  case EvalInfo::EM_ConstantFold:
  case EvalInfo::EM_EvaluateForOverflow:
  case EvalInfo::EM_IgnoreSideEffects:
  case EvalInfo::EM_OffsetFold:
    // Leave it to IR generation.
    return Error(E);
  case EvalInfo::EM_ConstantExpressionUnevaluated:
  case EvalInfo::EM_PotentialConstantExpressionUnevaluated:
    // Reduce it to a constant now.
    return Success((Type & 2) ? 0 : -1, E);
  }

  llvm_unreachable("unexpected EvalMode")::llvm::llvm_unreachable_internal("unexpected EvalMode", "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 7724);
}

case Builtin::BI__builtin_bswap16:
case Builtin::BI__builtin_bswap32:
case Builtin::BI__builtin_bswap64: {
  APSInt Val;
  if (!EvaluateInteger(E->getArg(0), Val, Info))
    return false;

  return Success(Val.byteSwap(), E);
}

case Builtin::BI__builtin_classify_type:
  return Success(EvaluateBuiltinClassifyType(E, Info.getLangOpts()), E);

// FIXME: BI__builtin_clrsb
// FIXME: BI__builtin_clrsbl
// FIXME: BI__builtin_clrsbll

case Builtin::BI__builtin_clz:
case Builtin::BI__builtin_clzl:
case Builtin::BI__builtin_clzll:
case Builtin::BI__builtin_clzs: {
  APSInt Val;
  if (!EvaluateInteger(E->getArg(0), Val, Info))
    return false;
  if (!Val)
    return Error(E);

  return Success(Val.countLeadingZeros(), E);
}

case Builtin::BI__builtin_constant_p:
  return Success(EvaluateBuiltinConstantP(Info.Ctx, E->getArg(0)), E);

case Builtin::BI__builtin_ctz:
case Builtin::BI__builtin_ctzl:
case Builtin::BI__builtin_ctzll:
case Builtin::BI__builtin_ctzs: {
  APSInt Val;
  if (!EvaluateInteger(E->getArg(0), Val, Info))
    return false;
  if (!Val)
    return Error(E);

  return Success(Val.countTrailingZeros(), E);
}

case Builtin::BI__builtin_eh_return_data_regno: {
  int Operand = E->getArg(0)->EvaluateKnownConstInt(Info.Ctx).getZExtValue();
  Operand = Info.Ctx.getTargetInfo().getEHDataRegisterNumber(Operand);
  return Success(Operand, E);
}

case Builtin::BI__builtin_expect:
  return Visit(E->getArg(0));

case Builtin::BI__builtin_ffs:
case Builtin::BI__builtin_ffsl:
case Builtin::BI__builtin_ffsll: {
  APSInt Val;
  if (!EvaluateInteger(E->getArg(0), Val, Info))
    return false;

  unsigned N = Val.countTrailingZeros();
  return Success(N == Val.getBitWidth() ? 0 : N + 1, E);
}

case Builtin::BI__builtin_fpclassify: {
  APFloat Val(0.0);
  if (!EvaluateFloat(E->getArg(5), Val, Info))
    return false;
  unsigned Arg;
  switch (Val.getCategory()) {
  case APFloat::fcNaN: Arg = 0; break;
  case APFloat::fcInfinity: Arg = 1; break;
  case APFloat::fcNormal: Arg = Val.isDenormal() ? 3 : 2; break;
  case APFloat::fcZero: Arg = 4; break;
  }
  return Visit(E->getArg(Arg));
}

case Builtin::BI__builtin_isinf_sign: {
  APFloat Val(0.0);
  return EvaluateFloat(E->getArg(0), Val, Info) &&
         Success(Val.isInfinity() ? (Val.isNegative() ? -1 : 1) : 0, E);
}

case Builtin::BI__builtin_isinf: {
  APFloat Val(0.0);
  return EvaluateFloat(E->getArg(0), Val, Info) &&
         Success(Val.isInfinity() ? 1 : 0, E);
}

case Builtin::BI__builtin_isfinite: {
  APFloat Val(0.0);
  return EvaluateFloat(E->getArg(0), Val, Info) &&
         Success(Val.isFinite() ? 1 : 0, E);
}

case Builtin::BI__builtin_isnan: {
  APFloat Val(0.0);
  return EvaluateFloat(E->getArg(0), Val, Info) &&
         Success(Val.isNaN() ? 1 : 0, E);
}

case Builtin::BI__builtin_isnormal: {
  APFloat Val(0.0);
  return EvaluateFloat(E->getArg(0), Val, Info) &&
         Success(Val.isNormal() ? 1 : 0, E);
}

case Builtin::BI__builtin_parity:
case Builtin::BI__builtin_parityl:
case Builtin::BI__builtin_parityll: {
  APSInt Val;
  if (!EvaluateInteger(E->getArg(0), Val, Info))
    return false;

  return Success(Val.countPopulation() % 2, E);
}

case Builtin::BI__builtin_popcount:
case Builtin::BI__builtin_popcountl:
case Builtin::BI__builtin_popcountll: {
  APSInt Val;
  if (!EvaluateInteger(E->getArg(0), Val, Info))
    return false;

  return Success(Val.countPopulation(), E);
}

case Builtin::BIstrlen:
case Builtin::BIwcslen:
  // A call to strlen is not a constant expression.
  if (Info.getLangOpts().CPlusPlus11)
    Info.CCEDiag(E, diag::note_constexpr_invalid_function)
      << /*isConstexpr*/0 << /*isConstructor*/0
      << (std::string("'") + Info.Ctx.BuiltinInfo.getName(BuiltinOp) + "'");
  else
    Info.CCEDiag(E, diag::note_invalid_subexpr_in_const_expr);
  LLVM_FALLTHROUGH[[clang::fallthrough]];
case Builtin::BI__builtin_strlen:
case Builtin::BI__builtin_wcslen: {
  // As an extension, we support __builtin_strlen() as a constant expression,
  // and support folding strlen() to a constant.
  LValue String;
  if (!EvaluatePointer(E->getArg(0), String, Info))
    return false;

  QualType CharTy = E->getArg(0)->getType()->getPointeeType();

  // Fast path: if it's a string literal, search the string value.
  if (const StringLiteral *S = dyn_cast_or_null<StringLiteral>(
          String.getLValueBase().dyn_cast<const Expr *>())) {
    // The string literal may have embedded null characters. Find the first
    // one and truncate there.
    StringRef Str = S->getBytes();
    int64_t Off = String.Offset.getQuantity();
    if (Off >= 0 && (uint64_t)Off <= (uint64_t)Str.size() &&
        S->getCharByteWidth() == 1 &&
        // FIXME: Add fast-path for wchar_t too.
        Info.Ctx.hasSameUnqualifiedType(CharTy, Info.Ctx.CharTy)) {
      Str = Str.substr(Off);

      StringRef::size_type Pos = Str.find(0);
      if (Pos != StringRef::npos)
        Str = Str.substr(0, Pos);

      return Success(Str.size(), E);
    }

    // Fall through to slow path to issue appropriate diagnostic.
  }

  // Slow path: scan the bytes of the string looking for the terminating 0.
  for (uint64_t Strlen = 0; /**/; ++Strlen) {
    APValue Char;
    if (!handleLValueToRValueConversion(Info, E, CharTy, String, Char) ||
        !Char.isInt())
      return false;
    if (!Char.getInt())
      return Success(Strlen, E);
    if (!HandleLValueArrayAdjustment(Info, E, String, CharTy, 1))
      return false;
  }
}

case Builtin::BIstrcmp:
case Builtin::BIwcscmp:
case Builtin::BIstrncmp:
case Builtin::BIwcsncmp:
case Builtin::BImemcmp:
case Builtin::BIwmemcmp:
  // A call to strlen is not a constant expression.
  if (Info.getLangOpts().CPlusPlus11)
    Info.CCEDiag(E, diag::note_constexpr_invalid_function)
      << /*isConstexpr*/0 << /*isConstructor*/0
      << (std::string("'") + Info.Ctx.BuiltinInfo.getName(BuiltinOp) + "'");
  else
    Info.CCEDiag(E, diag::note_invalid_subexpr_in_const_expr);
  LLVM_FALLTHROUGH[[clang::fallthrough]];
case Builtin::BI__builtin_strcmp:
case Builtin::BI__builtin_wcscmp:
case Builtin::BI__builtin_strncmp:
case Builtin::BI__builtin_wcsncmp:
case Builtin::BI__builtin_memcmp:
case Builtin::BI__builtin_wmemcmp: {
  LValue String1, String2;
  if (!EvaluatePointer(E->getArg(0), String1, Info) ||
      !EvaluatePointer(E->getArg(1), String2, Info))
    return false;

  QualType CharTy = E->getArg(0)->getType()->getPointeeType();

  uint64_t MaxLength = uint64_t(-1);
  if (BuiltinOp != Builtin::BIstrcmp &&
      BuiltinOp != Builtin::BIwcscmp &&
      BuiltinOp != Builtin::BI__builtin_strcmp &&
      BuiltinOp != Builtin::BI__builtin_wcscmp) {
    APSInt N;
    if (!EvaluateInteger(E->getArg(2), N, Info))
      return false;
    MaxLength = N.getExtValue();
  }
  bool StopAtNull = (BuiltinOp != Builtin::BImemcmp &&
                     BuiltinOp != Builtin::BIwmemcmp &&
                     BuiltinOp != Builtin::BI__builtin_memcmp &&
                     BuiltinOp != Builtin::BI__builtin_wmemcmp);
  for (; MaxLength; --MaxLength) {
    APValue Char1, Char2;
    if (!handleLValueToRValueConversion(Info, E, CharTy, String1, Char1) ||
        !handleLValueToRValueConversion(Info, E, CharTy, String2, Char2) ||
        !Char1.isInt() || !Char2.isInt())
      return false;
    if (Char1.getInt() != Char2.getInt())
      return Success(Char1.getInt() < Char2.getInt() ? -1 : 1, E);
    if (StopAtNull && !Char1.getInt())
      return Success(0, E);
    assert(!(StopAtNull && !Char2.getInt()))(static_cast <bool> (!(StopAtNull && !Char2.getInt
())) ? void (0) : __assert_fail ("!(StopAtNull && !Char2.getInt())"
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 7964, __extension__ __PRETTY_FUNCTION__));
    if (!HandleLValueArrayAdjustment(Info, E, String1, CharTy, 1) ||
        !HandleLValueArrayAdjustment(Info, E, String2, CharTy, 1))
      return false;
  }
  // We hit the strncmp / memcmp limit.
  return Success(0, E);
}

case Builtin::BI__atomic_always_lock_free:
case Builtin::BI__atomic_is_lock_free:
case Builtin::BI__c11_atomic_is_lock_free: {
  APSInt SizeVal;
  if (!EvaluateInteger(E->getArg(0), SizeVal, Info))
    return false;

  // For __atomic_is_lock_free(sizeof(_Atomic(T))), if the size is a power
  // of two less than the maximum inline atomic width, we know it is
  // lock-free.  If the size isn't a power of two, or greater than the
  // maximum alignment where we promote atomics, we know it is not lock-free
  // (at least not in the sense of atomic_is_lock_free).  Otherwise,
  // the answer can only be determined at runtime; for example, 16-byte
  // atomics have lock-free implementations on some, but not all,
  // x86-64 processors.

  // Check power-of-two.
  CharUnits Size = CharUnits::fromQuantity(SizeVal.getZExtValue());
  if (Size.isPowerOfTwo()) {
    // Check against inlining width.
    unsigned InlineWidthBits =
        Info.Ctx.getTargetInfo().getMaxAtomicInlineWidth();
    if (Size <= Info.Ctx.toCharUnitsFromBits(InlineWidthBits)) {
      if (BuiltinOp == Builtin::BI__c11_atomic_is_lock_free ||
          Size == CharUnits::One() ||
          E->getArg(1)->isNullPointerConstant(Info.Ctx,
                                              Expr::NPC_NeverValueDependent))
        // OK, we will inline appropriately-aligned operations of this size,
        // and _Atomic(T) is appropriately-aligned.
        return Success(1, E);

      QualType PointeeType = E->getArg(1)->IgnoreImpCasts()->getType()->
        castAs<PointerType>()->getPointeeType();
      if (!PointeeType->isIncompleteType() &&
          Info.Ctx.getTypeAlignInChars(PointeeType) >= Size) {
        // OK, we will inline operations on this object.
        return Success(1, E);
      }
    }
  }

  return BuiltinOp == Builtin::BI__atomic_always_lock_free ?
      Success(0, E) : Error(E);
}
case Builtin::BIomp_is_initial_device:
  // We can decide statically which value the runtime would return if called.
  return Success(Info.getLangOpts().OpenMPIsDevice ? 0 : 1, E);
}
8021}

8023static bool HasSameBase(const LValue &A, const LValue &B) {
if (!A.getLValueBase())
  return !B.getLValueBase();
if (!B.getLValueBase())
  return false;

if (A.getLValueBase().getOpaqueValue() !=
    B.getLValueBase().getOpaqueValue()) {
  const Decl *ADecl = GetLValueBaseDecl(A);
  if (!ADecl)
    return false;
  const Decl *BDecl = GetLValueBaseDecl(B);
  if (!BDecl || ADecl->getCanonicalDecl() != BDecl->getCanonicalDecl())
    return false;
}

return IsGlobalLValue(A.getLValueBase()) ||
       A.getLValueCallIndex() == B.getLValueCallIndex();
8041}

8043/// \brief Determine whether this is a pointer past the end of the complete
8044/// object referred to by the lvalue.
8045static bool isOnePastTheEndOfCompleteObject(const ASTContext &Ctx,
                                          const LValue &LV) {
// A null pointer can be viewed as being "past the end" but we don't
// choose to look at it that way here.
if (!LV.getLValueBase())
  return false;

// If the designator is valid and refers to a subobject, we're not pointing
// past the end.
if (!LV.getLValueDesignator().Invalid &&
    !LV.getLValueDesignator().isOnePastTheEnd())
  return false;

// A pointer to an incomplete type might be past-the-end if the type's size is
// zero.  We cannot tell because the type is incomplete.
QualType Ty = getType(LV.getLValueBase());
if (Ty->isIncompleteType())
  return true;

// We're a past-the-end pointer if we point to the byte after the object,
// no matter what our type or path is.
auto Size = Ctx.getTypeSizeInChars(Ty);
return LV.getLValueOffset() == Size;
8068}

8070namespace {

8072/// \brief Data recursive integer evaluator of certain binary operators.
8073///
8074/// We use a data recursive algorithm for binary operators so that we are able
8075/// to handle extreme cases of chained binary operators without causing stack
8076/// overflow.
8077class DataRecursiveIntBinOpEvaluator {
struct EvalResult {
  APValue Val;
  bool Failed;

  EvalResult() : Failed(false) { }

  void swap(EvalResult &RHS) {
    Val.swap(RHS.Val);
    Failed = RHS.Failed;
    RHS.Failed = false;
  }
};

struct Job {
  const Expr *E;
  EvalResult LHSResult; // meaningful only for binary operator expression.
  enum { AnyExprKind, BinOpKind, BinOpVisitedLHSKind } Kind;

  Job() = default;
  Job(Job &&) = default;

  void startSpeculativeEval(EvalInfo &Info) {
    SpecEvalRAII = SpeculativeEvaluationRAII(Info);
  }

private:
  SpeculativeEvaluationRAII SpecEvalRAII;
};

SmallVector<Job, 16> Queue;

IntExprEvaluator &IntEval;
EvalInfo &Info;
APValue &FinalResult;

8113public:
DataRecursiveIntBinOpEvaluator(IntExprEvaluator &IntEval, APValue &Result)
  : IntEval(IntEval), Info(IntEval.getEvalInfo()), FinalResult(Result) { }

/// \brief True if \param E is a binary operator that we are going to handle
/// data recursively.
/// We handle binary operators that are comma, logical, or that have operands
/// with integral or enumeration type.
static bool shouldEnqueue(const BinaryOperator *E) {
  return E->getOpcode() == BO_Comma ||
         E->isLogicalOp() ||
         (E->isRValue() &&
          E->getType()->isIntegralOrEnumerationType() &&
          E->getLHS()->getType()->isIntegralOrEnumerationType() &&
          E->getRHS()->getType()->isIntegralOrEnumerationType());
}

bool Traverse(const BinaryOperator *E) {
  enqueue(E);
  EvalResult PrevResult;
  while (!Queue.empty())
    process(PrevResult);

  if (PrevResult.Failed) return false;

  FinalResult.swap(PrevResult.Val);
  return true;
}

8142private:
bool Success(uint64_t Value, const Expr *E, APValue &Result) {
  return IntEval.Success(Value, E, Result);
}
bool Success(const APSInt &Value, const Expr *E, APValue &Result) {
  return IntEval.Success(Value, E, Result);
}
bool Error(const Expr *E) {
  return IntEval.Error(E);
}
bool Error(const Expr *E, diag::kind D) {
  return IntEval.Error(E, D);
}

OptionalDiagnostic CCEDiag(const Expr *E, diag::kind D) {
  return Info.CCEDiag(E, D);
}

// \brief Returns true if visiting the RHS is necessary, false otherwise.
bool VisitBinOpLHSOnly(EvalResult &LHSResult, const BinaryOperator *E,
                       bool &SuppressRHSDiags);

bool VisitBinOp(const EvalResult &LHSResult, const EvalResult &RHSResult,
                const BinaryOperator *E, APValue &Result);

void EvaluateExpr(const Expr *E, EvalResult &Result) {
  Result.Failed = !Evaluate(Result.Val, Info, E);
  if (Result.Failed)
    Result.Val = APValue();
}

void process(EvalResult &Result);

void enqueue(const Expr *E) {
  E = E->IgnoreParens();
  Queue.resize(Queue.size()+1);
  Queue.back().E = E;
  Queue.back().Kind = Job::AnyExprKind;
}
8181};

8183}

8185bool DataRecursiveIntBinOpEvaluator::
     VisitBinOpLHSOnly(EvalResult &LHSResult, const BinaryOperator *E,
                       bool &SuppressRHSDiags) {
if (E->getOpcode() == BO_Comma) {
  // Ignore LHS but note if we could not evaluate it.
  if (LHSResult.Failed)
    return Info.noteSideEffect();
  return true;
}

if (E->isLogicalOp()) {
  bool LHSAsBool;
  if (!LHSResult.Failed && HandleConversionToBool(LHSResult.Val, LHSAsBool)) {
    // We were able to evaluate the LHS, see if we can get away with not
    // evaluating the RHS: 0 && X -> 0, 1 || X -> 1
    if (LHSAsBool == (E->getOpcode() == BO_LOr)) {
      Success(LHSAsBool, E, LHSResult.Val);
      return false; // Ignore RHS
    }
  } else {
    LHSResult.Failed = true;

    // Since we weren't able to evaluate the left hand side, it
    // might have had side effects.
    if (!Info.noteSideEffect())
      return false;

    // We can't evaluate the LHS; however, sometimes the result
    // is determined by the RHS: X && 0 -> 0, X || 1 -> 1.
    // Don't ignore RHS and suppress diagnostics from this arm.
    SuppressRHSDiags = true;
  }

  return true;
}

assert(E->getLHS()->getType()->isIntegralOrEnumerationType() &&(static_cast <bool> (E->getLHS()->getType()->isIntegralOrEnumerationType
() && E->getRHS()->getType()->isIntegralOrEnumerationType
()) ? void (0) : __assert_fail ("E->getLHS()->getType()->isIntegralOrEnumerationType() && E->getRHS()->getType()->isIntegralOrEnumerationType()"
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 8222, __extension__ __PRETTY_FUNCTION__))
       E->getRHS()->getType()->isIntegralOrEnumerationType())(static_cast <bool> (E->getLHS()->getType()->isIntegralOrEnumerationType
() && E->getRHS()->getType()->isIntegralOrEnumerationType
()) ? void (0) : __assert_fail ("E->getLHS()->getType()->isIntegralOrEnumerationType() && E->getRHS()->getType()->isIntegralOrEnumerationType()"
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 8222, __extension__ __PRETTY_FUNCTION__));

if (LHSResult.Failed && !Info.noteFailure())
  return false; // Ignore RHS;

return true;
8228}

8230static void addOrSubLValueAsInteger(APValue &LVal, const APSInt &Index,
                                  bool IsSub) {
// Compute the new offset in the appropriate width, wrapping at 64 bits.
// FIXME: When compiling for a 32-bit target, we should use 32-bit
// offsets.
assert(!LVal.hasLValuePath() && "have designator for integer lvalue")(static_cast <bool> (!LVal.hasLValuePath() && "have designator for integer lvalue"
) ? void (0) : __assert_fail ("!LVal.hasLValuePath() && \"have designator for integer lvalue\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 8235, __extension__ __PRETTY_FUNCTION__));
CharUnits &Offset = LVal.getLValueOffset();
uint64_t Offset64 = Offset.getQuantity();
uint64_t Index64 = Index.extOrTrunc(64).getZExtValue();
Offset = CharUnits::fromQuantity(IsSub ? Offset64 - Index64
                                       : Offset64 + Index64);
8241}

8243bool DataRecursiveIntBinOpEvaluator::
     VisitBinOp(const EvalResult &LHSResult, const EvalResult &RHSResult,
                const BinaryOperator *E, APValue &Result) {
if (E->getOpcode() == BO_Comma) {
  if (RHSResult.Failed)
    return false;
  Result = RHSResult.Val;
  return true;
}

if (E->isLogicalOp()) {
  bool lhsResult, rhsResult;
  bool LHSIsOK = HandleConversionToBool(LHSResult.Val, lhsResult);
  bool RHSIsOK = HandleConversionToBool(RHSResult.Val, rhsResult);
  
  if (LHSIsOK) {
    if (RHSIsOK) {
      if (E->getOpcode() == BO_LOr)
        return Success(lhsResult || rhsResult, E, Result);
      else
        return Success(lhsResult && rhsResult, E, Result);
    }
  } else {
    if (RHSIsOK) {
      // We can't evaluate the LHS; however, sometimes the result
      // is determined by the RHS: X && 0 -> 0, X || 1 -> 1.
      if (rhsResult == (E->getOpcode() == BO_LOr))
        return Success(rhsResult, E, Result);
    }
  }
  
  return false;
}

assert(E->getLHS()->getType()->isIntegralOrEnumerationType() &&(static_cast <bool> (E->getLHS()->getType()->isIntegralOrEnumerationType
() && E->getRHS()->getType()->isIntegralOrEnumerationType
()) ? void (0) : __assert_fail ("E->getLHS()->getType()->isIntegralOrEnumerationType() && E->getRHS()->getType()->isIntegralOrEnumerationType()"
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 8278, __extension__ __PRETTY_FUNCTION__))
       E->getRHS()->getType()->isIntegralOrEnumerationType())(static_cast <bool> (E->getLHS()->getType()->isIntegralOrEnumerationType
() && E->getRHS()->getType()->isIntegralOrEnumerationType
()) ? void (0) : __assert_fail ("E->getLHS()->getType()->isIntegralOrEnumerationType() && E->getRHS()->getType()->isIntegralOrEnumerationType()"
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 8278, __extension__ __PRETTY_FUNCTION__));

if (LHSResult.Failed || RHSResult.Failed)
  return false;

const APValue &LHSVal = LHSResult.Val;
const APValue &RHSVal = RHSResult.Val;

// Handle cases like (unsigned long)&a + 4.
if (E->isAdditiveOp() && LHSVal.isLValue() && RHSVal.isInt()) {
  Result = LHSVal;
  addOrSubLValueAsInteger(Result, RHSVal.getInt(), E->getOpcode() == BO_Sub);
  return true;
}

// Handle cases like 4 + (unsigned long)&a
if (E->getOpcode() == BO_Add &&
    RHSVal.isLValue() && LHSVal.isInt()) {
  Result = RHSVal;
  addOrSubLValueAsInteger(Result, LHSVal.getInt(), /*IsSub*/false);
  return true;
}

if (E->getOpcode() == BO_Sub && LHSVal.isLValue() && RHSVal.isLValue()) {
  // Handle (intptr_t)&&A - (intptr_t)&&B.
  if (!LHSVal.getLValueOffset().isZero() ||
      !RHSVal.getLValueOffset().isZero())
    return false;
  const Expr *LHSExpr = LHSVal.getLValueBase().dyn_cast<const Expr*>();
  const Expr *RHSExpr = RHSVal.getLValueBase().dyn_cast<const Expr*>();
  if (!LHSExpr || !RHSExpr)
    return false;
  const AddrLabelExpr *LHSAddrExpr = dyn_cast<AddrLabelExpr>(LHSExpr);
  const AddrLabelExpr *RHSAddrExpr = dyn_cast<AddrLabelExpr>(RHSExpr);
  if (!LHSAddrExpr || !RHSAddrExpr)
    return false;
  // Make sure both labels come from the same function.
  if (LHSAddrExpr->getLabel()->getDeclContext() !=
      RHSAddrExpr->getLabel()->getDeclContext())
    return false;
  Result = APValue(LHSAddrExpr, RHSAddrExpr);
  return true;
}

// All the remaining cases expect both operands to be an integer
if (!LHSVal.isInt() || !RHSVal.isInt())
  return Error(E);

// Set up the width and signedness manually, in case it can't be deduced
// from the operation we're performing.
// FIXME: Don't do this in the cases where we can deduce it.
APSInt Value(Info.Ctx.getIntWidth(E->getType()),
             E->getType()->isUnsignedIntegerOrEnumerationType());
if (!handleIntIntBinOp(Info, E, LHSVal.getInt(), E->getOpcode(),
                       RHSVal.getInt(), Value))
  return false;
return Success(Value, E, Result);
8335}

8337void DataRecursiveIntBinOpEvaluator::process(EvalResult &Result) {
Job &job = Queue.back();

switch (job.Kind) {
  case Job::AnyExprKind: {
    if (const BinaryOperator *Bop = dyn_cast<BinaryOperator>(job.E)) {
      if (shouldEnqueue(Bop)) {
        job.Kind = Job::BinOpKind;
        enqueue(Bop->getLHS());
        return;
      }
    }
    
    EvaluateExpr(job.E, Result);
    Queue.pop_back();
    return;
  }
    
  case Job::BinOpKind: {
    const BinaryOperator *Bop = cast<BinaryOperator>(job.E);
    bool SuppressRHSDiags = false;
    if (!VisitBinOpLHSOnly(Result, Bop, SuppressRHSDiags)) {
      Queue.pop_back();
      return;
    }
    if (SuppressRHSDiags)
      job.startSpeculativeEval(Info);
    job.LHSResult.swap(Result);
    job.Kind = Job::BinOpVisitedLHSKind;
    enqueue(Bop->getRHS());
    return;
  }
    
  case Job::BinOpVisitedLHSKind: {
    const BinaryOperator *Bop = cast<BinaryOperator>(job.E);
    EvalResult RHS;
    RHS.swap(Result);
    Result.Failed = !VisitBinOp(job.LHSResult, RHS, Bop, Result.Val);
    Queue.pop_back();
    return;
  }
}

llvm_unreachable("Invalid Job::Kind!")::llvm::llvm_unreachable_internal("Invalid Job::Kind!", "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 8380);
8381}

8383namespace {
8384/// Used when we determine that we should fail, but can keep evaluating prior to
8385/// noting that we had a failure.
8386class DelayedNoteFailureRAII {
EvalInfo &Info;
bool NoteFailure;

8390public:
DelayedNoteFailureRAII(EvalInfo &Info, bool NoteFailure = true)
    : Info(Info), NoteFailure(NoteFailure) {}
~DelayedNoteFailureRAII() {
  if (NoteFailure) {
    bool ContinueAfterFailure = Info.noteFailure();
    (void)ContinueAfterFailure;
    assert(ContinueAfterFailure &&(static_cast <bool> (ContinueAfterFailure && "Shouldn't have kept evaluating on failure."
) ? void (0) : __assert_fail ("ContinueAfterFailure && \"Shouldn't have kept evaluating on failure.\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 8398, __extension__ __PRETTY_FUNCTION__))
           "Shouldn't have kept evaluating on failure.")(static_cast <bool> (ContinueAfterFailure && "Shouldn't have kept evaluating on failure."
) ? void (0) : __assert_fail ("ContinueAfterFailure && \"Shouldn't have kept evaluating on failure.\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 8398, __extension__ __PRETTY_FUNCTION__));
  }
}
8401};
8402}

8404bool IntExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) {
// We don't call noteFailure immediately because the assignment happens after
// we evaluate LHS and RHS.
if (!Info.keepEvaluatingAfterFailure() && E->isAssignmentOp())
  return Error(E);

DelayedNoteFailureRAII MaybeNoteFailureLater(Info, E->isAssignmentOp());
if (DataRecursiveIntBinOpEvaluator::shouldEnqueue(E))
  return DataRecursiveIntBinOpEvaluator(*this, Result).Traverse(E);

QualType LHSTy = E->getLHS()->getType();
QualType RHSTy = E->getRHS()->getType();

if (LHSTy->isAnyComplexType() || RHSTy->isAnyComplexType()) {
  ComplexValue LHS, RHS;
  bool LHSOK;
  if (E->isAssignmentOp()) {
    LValue LV;
    EvaluateLValue(E->getLHS(), LV, Info);
    LHSOK = false;
  } else if (LHSTy->isRealFloatingType()) {
    LHSOK = EvaluateFloat(E->getLHS(), LHS.FloatReal, Info);
    if (LHSOK) {
      LHS.makeComplexFloat();
      LHS.FloatImag = APFloat(LHS.FloatReal.getSemantics());
    }
  } else {
    LHSOK = EvaluateComplex(E->getLHS(), LHS, Info);
  }
  if (!LHSOK && !Info.noteFailure())
    return false;

  if (E->getRHS()->getType()->isRealFloatingType()) {
    if (!EvaluateFloat(E->getRHS(), RHS.FloatReal, Info) || !LHSOK)
      return false;
    RHS.makeComplexFloat();
    RHS.FloatImag = APFloat(RHS.FloatReal.getSemantics());
  } else if (!EvaluateComplex(E->getRHS(), RHS, Info) || !LHSOK)
    return false;

  if (LHS.isComplexFloat()) {
    APFloat::cmpResult CR_r =
      LHS.getComplexFloatReal().compare(RHS.getComplexFloatReal());
    APFloat::cmpResult CR_i =
      LHS.getComplexFloatImag().compare(RHS.getComplexFloatImag());

    if (E->getOpcode() == BO_EQ)
      return Success((CR_r == APFloat::cmpEqual &&
                      CR_i == APFloat::cmpEqual), E);
    else {
      assert(E->getOpcode() == BO_NE &&(static_cast <bool> (E->getOpcode() == BO_NE &&
 "Invalid complex comparison.") ? void (0) : __assert_fail ("E->getOpcode() == BO_NE && \"Invalid complex comparison.\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 8455, __extension__ __PRETTY_FUNCTION__))
             "Invalid complex comparison.")(static_cast <bool> (E->getOpcode() == BO_NE &&
 "Invalid complex comparison.") ? void (0) : __assert_fail ("E->getOpcode() == BO_NE && \"Invalid complex comparison.\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 8455, __extension__ __PRETTY_FUNCTION__));
      return Success(((CR_r == APFloat::cmpGreaterThan ||
                       CR_r == APFloat::cmpLessThan ||
                       CR_r == APFloat::cmpUnordered) ||
                      (CR_i == APFloat::cmpGreaterThan ||
                       CR_i == APFloat::cmpLessThan ||
                       CR_i == APFloat::cmpUnordered)), E);
    }
  } else {
    if (E->getOpcode() == BO_EQ)
      return Success((LHS.getComplexIntReal() == RHS.getComplexIntReal() &&
                      LHS.getComplexIntImag() == RHS.getComplexIntImag()), E);
    else {
      assert(E->getOpcode() == BO_NE &&(static_cast <bool> (E->getOpcode() == BO_NE &&
 "Invalid compex comparison.") ? void (0) : __assert_fail ("E->getOpcode() == BO_NE && \"Invalid compex comparison.\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 8469, __extension__ __PRETTY_FUNCTION__))
             "Invalid compex comparison.")(static_cast <bool> (E->getOpcode() == BO_NE &&
 "Invalid compex comparison.") ? void (0) : __assert_fail ("E->getOpcode() == BO_NE && \"Invalid compex comparison.\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 8469, __extension__ __PRETTY_FUNCTION__));
      return Success((LHS.getComplexIntReal() != RHS.getComplexIntReal() ||
                      LHS.getComplexIntImag() != RHS.getComplexIntImag()), E);
    }
  }
}

if (LHSTy->isRealFloatingType() &&
    RHSTy->isRealFloatingType()) {
  APFloat RHS(0.0), LHS(0.0);

  bool LHSOK = EvaluateFloat(E->getRHS(), RHS, Info);
  if (!LHSOK && !Info.noteFailure())
    return false;

  if (!EvaluateFloat(E->getLHS(), LHS, Info) || !LHSOK)
    return false;

  APFloat::cmpResult CR = LHS.compare(RHS);

  switch (E->getOpcode()) {
  default:
    llvm_unreachable("Invalid binary operator!")::llvm::llvm_unreachable_internal("Invalid binary operator!",
 "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 8491);
  case BO_LT:
    return Success(CR == APFloat::cmpLessThan, E);
  case BO_GT:
    return Success(CR == APFloat::cmpGreaterThan, E);
  case BO_LE:
    return Success(CR == APFloat::cmpLessThan || CR == APFloat::cmpEqual, E);
  case BO_GE:
    return Success(CR == APFloat::cmpGreaterThan || CR == APFloat::cmpEqual,
                   E);
  case BO_EQ:
    return Success(CR == APFloat::cmpEqual, E);
  case BO_NE:
    return Success(CR == APFloat::cmpGreaterThan
                   || CR == APFloat::cmpLessThan
                   || CR == APFloat::cmpUnordered, E);
  }
}

if (LHSTy->isPointerType() && RHSTy->isPointerType()) {
  if (E->getOpcode() == BO_Sub || E->isComparisonOp()) {
    LValue LHSValue, RHSValue;

    bool LHSOK = EvaluatePointer(E->getLHS(), LHSValue, Info);
    if (!LHSOK && !Info.noteFailure())
      return false;

    if (!EvaluatePointer(E->getRHS(), RHSValue, Info) || !LHSOK)
      return false;

    // Reject differing bases from the normal codepath; we special-case
    // comparisons to null.
    if (!HasSameBase(LHSValue, RHSValue)) {
      if (E->getOpcode() == BO_Sub) {
        // Handle &&A - &&B.
        if (!LHSValue.Offset.isZero() || !RHSValue.Offset.isZero())
          return Error(E);
        const Expr *LHSExpr = LHSValue.Base.dyn_cast<const Expr*>();
        const Expr *RHSExpr = RHSValue.Base.dyn_cast<const Expr*>();
        if (!LHSExpr || !RHSExpr)
          return Error(E);
        const AddrLabelExpr *LHSAddrExpr = dyn_cast<AddrLabelExpr>(LHSExpr);
        const AddrLabelExpr *RHSAddrExpr = dyn_cast<AddrLabelExpr>(RHSExpr);
        if (!LHSAddrExpr || !RHSAddrExpr)
          return Error(E);
        // Make sure both labels come from the same function.
        if (LHSAddrExpr->getLabel()->getDeclContext() !=
            RHSAddrExpr->getLabel()->getDeclContext())
          return Error(E);
        return Success(APValue(LHSAddrExpr, RHSAddrExpr), E);
      }
      // Inequalities and subtractions between unrelated pointers have
      // unspecified or undefined behavior.
      if (!E->isEqualityOp())
        return Error(E);
      // A constant address may compare equal to the address of a symbol.
      // The one exception is that address of an object cannot compare equal
      // to a null pointer constant.
      if ((!LHSValue.Base && !LHSValue.Offset.isZero()) ||
          (!RHSValue.Base && !RHSValue.Offset.isZero()))
        return Error(E);
      // It's implementation-defined whether distinct literals will have
      // distinct addresses. In clang, the result of such a comparison is
      // unspecified, so it is not a constant expression. However, we do know
      // that the address of a literal will be non-null.
      if ((IsLiteralLValue(LHSValue) || IsLiteralLValue(RHSValue)) &&
          LHSValue.Base && RHSValue.Base)
        return Error(E);
      // We can't tell whether weak symbols will end up pointing to the same
      // object.
      if (IsWeakLValue(LHSValue) || IsWeakLValue(RHSValue))
        return Error(E);
      // We can't compare the address of the start of one object with the
      // past-the-end address of another object, per C++ DR1652.
      if ((LHSValue.Base && LHSValue.Offset.isZero() &&
           isOnePastTheEndOfCompleteObject(Info.Ctx, RHSValue)) ||
          (RHSValue.Base && RHSValue.Offset.isZero() &&
           isOnePastTheEndOfCompleteObject(Info.Ctx, LHSValue)))
        return Error(E);
      // We can't tell whether an object is at the same address as another
      // zero sized object.
      if ((RHSValue.Base && isZeroSized(LHSValue)) ||
          (LHSValue.Base && isZeroSized(RHSValue)))
        return Error(E);
      // Pointers with different bases cannot represent the same object.
      // (Note that clang defaults to -fmerge-all-constants, which can
      // lead to inconsistent results for comparisons involving the address
      // of a constant; this generally doesn't matter in practice.)
      return Success(E->getOpcode() == BO_NE, E);
    }

    const CharUnits &LHSOffset = LHSValue.getLValueOffset();
    const CharUnits &RHSOffset = RHSValue.getLValueOffset();

    SubobjectDesignator &LHSDesignator = LHSValue.getLValueDesignator();
    SubobjectDesignator &RHSDesignator = RHSValue.getLValueDesignator();

    if (E->getOpcode() == BO_Sub) {
      // C++11 [expr.add]p6:
      //   Unless both pointers point to elements of the same array object, or
      //   one past the last element of the array object, the behavior is
      //   undefined.
      if (!LHSDesignator.Invalid && !RHSDesignator.Invalid &&
          !AreElementsOfSameArray(getType(LHSValue.Base),
                                  LHSDesignator, RHSDesignator))
        CCEDiag(E, diag::note_constexpr_pointer_subtraction_not_same_array);

      QualType Type = E->getLHS()->getType();
      QualType ElementType = Type->getAs<PointerType>()->getPointeeType();

      CharUnits ElementSize;
      if (!HandleSizeof(Info, E->getExprLoc(), ElementType, ElementSize))
        return false;

      // As an extension, a type may have zero size (empty struct or union in
      // C, array of zero length). Pointer subtraction in such cases has
      // undefined behavior, so is not constant.
      if (ElementSize.isZero()) {
        Info.FFDiag(E, diag::note_constexpr_pointer_subtraction_zero_size)
          << ElementType;
        return false;
      }

      // FIXME: LLVM and GCC both compute LHSOffset - RHSOffset at runtime,
      // and produce incorrect results when it overflows. Such behavior
      // appears to be non-conforming, but is common, so perhaps we should
      // assume the standard intended for such cases to be undefined behavior
      // and check for them.

      // Compute (LHSOffset - RHSOffset) / Size carefully, checking for
      // overflow in the final conversion to ptrdiff_t.
      APSInt LHS(
        llvm::APInt(65, (int64_t)LHSOffset.getQuantity(), true), false);
      APSInt RHS(
        llvm::APInt(65, (int64_t)RHSOffset.getQuantity(), true), false);
      APSInt ElemSize(
        llvm::APInt(65, (int64_t)ElementSize.getQuantity(), true), false);
      APSInt TrueResult = (LHS - RHS) / ElemSize;
      APSInt Result = TrueResult.trunc(Info.Ctx.getIntWidth(E->getType()));

      if (Result.extend(65) != TrueResult &&
          !HandleOverflow(Info, E, TrueResult, E->getType()))
        return false;
      return Success(Result, E);
    }

    // C++11 [expr.rel]p3:
    //   Pointers to void (after pointer conversions) can be compared, with a
    //   result defined as follows: If both pointers represent the same
    //   address or are both the null pointer value, the result is true if the
    //   operator is <= or >= and false otherwise; otherwise the result is
    //   unspecified.
    // We interpret this as applying to pointers to *cv* void.
    if (LHSTy->isVoidPointerType() && LHSOffset != RHSOffset &&
        E->isRelationalOp())
      CCEDiag(E, diag::note_constexpr_void_comparison);

    // C++11 [expr.rel]p2:
    // - If two pointers point to non-static data members of the same object,
    //   or to subobjects or array elements fo such members, recursively, the
    //   pointer to the later declared member compares greater provided the
    //   two members have the same access control and provided their class is
    //   not a union.
    //   [...]
    // - Otherwise pointer comparisons are unspecified.
    if (!LHSDesignator.Invalid && !RHSDesignator.Invalid &&
        E->isRelationalOp()) {
      bool WasArrayIndex;
      unsigned Mismatch =
        FindDesignatorMismatch(getType(LHSValue.Base), LHSDesignator,
                               RHSDesignator, WasArrayIndex);
      // At the point where the designators diverge, the comparison has a
      // specified value if:
      //  - we are comparing array indices
      //  - we are comparing fields of a union, or fields with the same access
      // Otherwise, the result is unspecified and thus the comparison is not a
      // constant expression.
      if (!WasArrayIndex && Mismatch < LHSDesignator.Entries.size() &&
          Mismatch < RHSDesignator.Entries.size()) {
        const FieldDecl *LF = getAsField(LHSDesignator.Entries[Mismatch]);
        const FieldDecl *RF = getAsField(RHSDesignator.Entries[Mismatch]);
        if (!LF && !RF)
          CCEDiag(E, diag::note_constexpr_pointer_comparison_base_classes);
        else if (!LF)
          CCEDiag(E, diag::note_constexpr_pointer_comparison_base_field)
            << getAsBaseClass(LHSDesignator.Entries[Mismatch])
            << RF->getParent() << RF;
        else if (!RF)
          CCEDiag(E, diag::note_constexpr_pointer_comparison_base_field)
            << getAsBaseClass(RHSDesignator.Entries[Mismatch])
            << LF->getParent() << LF;
        else if (!LF->getParent()->isUnion() &&
                 LF->getAccess() != RF->getAccess())
          CCEDiag(E, diag::note_constexpr_pointer_comparison_differing_access)
            << LF << LF->getAccess() << RF << RF->getAccess()
            << LF->getParent();
      }
    }

    // The comparison here must be unsigned, and performed with the same
    // width as the pointer.
    unsigned PtrSize = Info.Ctx.getTypeSize(LHSTy);
    uint64_t CompareLHS = LHSOffset.getQuantity();
    uint64_t CompareRHS = RHSOffset.getQuantity();
    assert(PtrSize <= 64 && "Unexpected pointer width")(static_cast <bool> (PtrSize <= 64 && "Unexpected pointer width"
) ? void (0) : __assert_fail ("PtrSize <= 64 && \"Unexpected pointer width\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 8695, __extension__ __PRETTY_FUNCTION__));
    uint64_t Mask = ~0ULL >> (64 - PtrSize);
    CompareLHS &= Mask;
    CompareRHS &= Mask;

    // If there is a base and this is a relational operator, we can only
    // compare pointers within the object in question; otherwise, the result
    // depends on where the object is located in memory.
    if (!LHSValue.Base.isNull() && E->isRelationalOp()) {
      QualType BaseTy = getType(LHSValue.Base);
      if (BaseTy->isIncompleteType())
        return Error(E);
      CharUnits Size = Info.Ctx.getTypeSizeInChars(BaseTy);
      uint64_t OffsetLimit = Size.getQuantity();
      if (CompareLHS > OffsetLimit || CompareRHS > OffsetLimit)
        return Error(E);
    }

    switch (E->getOpcode()) {
    default: llvm_unreachable("missing comparison operator")::llvm::llvm_unreachable_internal("missing comparison operator"
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 8714);
    case BO_LT: return Success(CompareLHS < CompareRHS, E);
    case BO_GT: return Success(CompareLHS > CompareRHS, E);
    case BO_LE: return Success(CompareLHS <= CompareRHS, E);
    case BO_GE: return Success(CompareLHS >= CompareRHS, E);
    case BO_EQ: return Success(CompareLHS == CompareRHS, E);
    case BO_NE: return Success(CompareLHS != CompareRHS, E);
    }
  }
}

if (LHSTy->isMemberPointerType()) {
  assert(E->isEqualityOp() && "unexpected member pointer operation")(static_cast <bool> (E->isEqualityOp() && "unexpected member pointer operation"
) ? void (0) : __assert_fail ("E->isEqualityOp() && \"unexpected member pointer operation\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 8726, __extension__ __PRETTY_FUNCTION__));
  assert(RHSTy->isMemberPointerType() && "invalid comparison")(static_cast <bool> (RHSTy->isMemberPointerType() &&
 "invalid comparison") ? void (0) : __assert_fail ("RHSTy->isMemberPointerType() && \"invalid comparison\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 8727, __extension__ __PRETTY_FUNCTION__));

  MemberPtr LHSValue, RHSValue;

  bool LHSOK = EvaluateMemberPointer(E->getLHS(), LHSValue, Info);
  if (!LHSOK && !Info.noteFailure())
    return false;

  if (!EvaluateMemberPointer(E->getRHS(), RHSValue, Info) || !LHSOK)
    return false;

  // C++11 [expr.eq]p2:
  //   If both operands are null, they compare equal. Otherwise if only one is
  //   null, they compare unequal.
  if (!LHSValue.getDecl() || !RHSValue.getDecl()) {
    bool Equal = !LHSValue.getDecl() && !RHSValue.getDecl();
    return Success(E->getOpcode() == BO_EQ ? Equal : !Equal, E);
  }

  //   Otherwise if either is a pointer to a virtual member function, the
  //   result is unspecified.
  if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(LHSValue.getDecl()))
    if (MD->isVirtual())
      CCEDiag(E, diag::note_constexpr_compare_virtual_mem_ptr) << MD;
  if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(RHSValue.getDecl()))
    if (MD->isVirtual())
      CCEDiag(E, diag::note_constexpr_compare_virtual_mem_ptr) << MD;

  //   Otherwise they compare equal if and only if they would refer to the
  //   same member of the same most derived object or the same subobject if
  //   they were dereferenced with a hypothetical object of the associated
  //   class type.
  bool Equal = LHSValue == RHSValue;
  return Success(E->getOpcode() == BO_EQ ? Equal : !Equal, E);
}

if (LHSTy->isNullPtrType()) {
  assert(E->isComparisonOp() && "unexpected nullptr operation")(static_cast <bool> (E->isComparisonOp() && "unexpected nullptr operation"
) ? void (0) : __assert_fail ("E->isComparisonOp() && \"unexpected nullptr operation\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 8764, __extension__ __PRETTY_FUNCTION__));
  assert(RHSTy->isNullPtrType() && "missing pointer conversion")(static_cast <bool> (RHSTy->isNullPtrType() &&
 "missing pointer conversion") ? void (0) : __assert_fail ("RHSTy->isNullPtrType() && \"missing pointer conversion\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 8765, __extension__ __PRETTY_FUNCTION__));
  // C++11 [expr.rel]p4, [expr.eq]p3: If two operands of type std::nullptr_t
  // are compared, the result is true of the operator is <=, >= or ==, and
  // false otherwise.
  BinaryOperator::Opcode Opcode = E->getOpcode();
  return Success(Opcode == BO_EQ || Opcode == BO_LE || Opcode == BO_GE, E);
}

assert((!LHSTy->isIntegralOrEnumerationType() ||(static_cast <bool> ((!LHSTy->isIntegralOrEnumerationType
() || !RHSTy->isIntegralOrEnumerationType()) && "DataRecursiveIntBinOpEvaluator should have handled integral types"
) ? void (0) : __assert_fail ("(!LHSTy->isIntegralOrEnumerationType() || !RHSTy->isIntegralOrEnumerationType()) && \"DataRecursiveIntBinOpEvaluator should have handled integral types\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 8775, __extension__ __PRETTY_FUNCTION__))
        !RHSTy->isIntegralOrEnumerationType()) &&(static_cast <bool> ((!LHSTy->isIntegralOrEnumerationType
() || !RHSTy->isIntegralOrEnumerationType()) && "DataRecursiveIntBinOpEvaluator should have handled integral types"
) ? void (0) : __assert_fail ("(!LHSTy->isIntegralOrEnumerationType() || !RHSTy->isIntegralOrEnumerationType()) && \"DataRecursiveIntBinOpEvaluator should have handled integral types\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 8775, __extension__ __PRETTY_FUNCTION__))
       "DataRecursiveIntBinOpEvaluator should have handled integral types")(static_cast <bool> ((!LHSTy->isIntegralOrEnumerationType
() || !RHSTy->isIntegralOrEnumerationType()) && "DataRecursiveIntBinOpEvaluator should have handled integral types"
) ? void (0) : __assert_fail ("(!LHSTy->isIntegralOrEnumerationType() || !RHSTy->isIntegralOrEnumerationType()) && \"DataRecursiveIntBinOpEvaluator should have handled integral types\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 8775, __extension__ __PRETTY_FUNCTION__));
// We can't continue from here for non-integral types.
return ExprEvaluatorBaseTy::VisitBinaryOperator(E);
8778}

8780/// VisitUnaryExprOrTypeTraitExpr - Evaluate a sizeof, alignof or vec_step with
8781/// a result as the expression's type.
8782bool IntExprEvaluator::VisitUnaryExprOrTypeTraitExpr(
                                  const UnaryExprOrTypeTraitExpr *E) {
switch(E->getKind()) {
case UETT_AlignOf: {
  if (E->isArgumentType())
    return Success(GetAlignOfType(Info, E->getArgumentType()), E);
  else
    return Success(GetAlignOfExpr(Info, E->getArgumentExpr()), E);
}

case UETT_VecStep: {
  QualType Ty = E->getTypeOfArgument();

  if (Ty->isVectorType()) {
    unsigned n = Ty->castAs<VectorType>()->getNumElements();

    // The vec_step built-in functions that take a 3-component
    // vector return 4. (OpenCL 1.1 spec 6.11.12)
    if (n == 3)
      n = 4;

    return Success(n, E);
  } else
    return Success(1, E);
}

case UETT_SizeOf: {
  QualType SrcTy = E->getTypeOfArgument();
  // C++ [expr.sizeof]p2: "When applied to a reference or a reference type,
  //   the result is the size of the referenced type."
  if (const ReferenceType *Ref = SrcTy->getAs<ReferenceType>())
    SrcTy = Ref->getPointeeType();

  CharUnits Sizeof;
  if (!HandleSizeof(Info, E->getExprLoc(), SrcTy, Sizeof))
    return false;
  return Success(Sizeof, E);
}
case UETT_OpenMPRequiredSimdAlign:
  assert(E->isArgumentType())(static_cast <bool> (E->isArgumentType()) ? void (0)
 : __assert_fail ("E->isArgumentType()", "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 8821, __extension__ __PRETTY_FUNCTION__));
  return Success(
      Info.Ctx.toCharUnitsFromBits(
                  Info.Ctx.getOpenMPDefaultSimdAlign(E->getArgumentType()))
          .getQuantity(),
      E);
}

llvm_unreachable("unknown expr/type trait")::llvm::llvm_unreachable_internal("unknown expr/type trait", "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 8829);
8830}

8832bool IntExprEvaluator::VisitOffsetOfExpr(const OffsetOfExpr *OOE) {
CharUnits Result;
unsigned n = OOE->getNumComponents();
if (n == 0)
  return Error(OOE);
QualType CurrentType = OOE->getTypeSourceInfo()->getType();
for (unsigned i = 0; i != n; ++i) {
  OffsetOfNode ON = OOE->getComponent(i);
  switch (ON.getKind()) {
  case OffsetOfNode::Array: {
    const Expr *Idx = OOE->getIndexExpr(ON.getArrayExprIndex());
    APSInt IdxResult;
    if (!EvaluateInteger(Idx, IdxResult, Info))
      return false;
    const ArrayType *AT = Info.Ctx.getAsArrayType(CurrentType);
    if (!AT)
      return Error(OOE);
    CurrentType = AT->getElementType();
    CharUnits ElementSize = Info.Ctx.getTypeSizeInChars(CurrentType);
    Result += IdxResult.getSExtValue() * ElementSize;
    break;
  }

  case OffsetOfNode::Field: {
    FieldDecl *MemberDecl = ON.getField();
    const RecordType *RT = CurrentType->getAs<RecordType>();
    if (!RT)
      return Error(OOE);
    RecordDecl *RD = RT->getDecl();
    if (RD->isInvalidDecl()) return false;
    const ASTRecordLayout &RL = Info.Ctx.getASTRecordLayout(RD);
    unsigned i = MemberDecl->getFieldIndex();
    assert(i < RL.getFieldCount() && "offsetof field in wrong type")(static_cast <bool> (i < RL.getFieldCount() &&
 "offsetof field in wrong type") ? void (0) : __assert_fail (
"i < RL.getFieldCount() && \"offsetof field in wrong type\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 8864, __extension__ __PRETTY_FUNCTION__));
    Result += Info.Ctx.toCharUnitsFromBits(RL.getFieldOffset(i));
    CurrentType = MemberDecl->getType().getNonReferenceType();
    break;
  }

  case OffsetOfNode::Identifier:
    llvm_unreachable("dependent __builtin_offsetof")::llvm::llvm_unreachable_internal("dependent __builtin_offsetof"
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 8871);

  case OffsetOfNode::Base: {
    CXXBaseSpecifier *BaseSpec = ON.getBase();
    if (BaseSpec->isVirtual())
      return Error(OOE);

    // Find the layout of the class whose base we are looking into.
    const RecordType *RT = CurrentType->getAs<RecordType>();
    if (!RT)
      return Error(OOE);
    RecordDecl *RD = RT->getDecl();
    if (RD->isInvalidDecl()) return false;
    const ASTRecordLayout &RL = Info.Ctx.getASTRecordLayout(RD);

    // Find the base class itself.
    CurrentType = BaseSpec->getType();
    const RecordType *BaseRT = CurrentType->getAs<RecordType>();
    if (!BaseRT)
      return Error(OOE);
    
    // Add the offset to the base.
    Result += RL.getBaseClassOffset(cast<CXXRecordDecl>(BaseRT->getDecl()));
    break;
  }
  }
}
return Success(Result, OOE);
8899}

8901bool IntExprEvaluator::VisitUnaryOperator(const UnaryOperator *E) {
switch (E->getOpcode()) {
default:
  // Address, indirect, pre/post inc/dec, etc are not valid constant exprs.
  // See C99 6.6p3.
  return Error(E);
case UO_Extension:
  // FIXME: Should extension allow i-c-e extension expressions in its scope?
  // If so, we could clear the diagnostic ID.
  return Visit(E->getSubExpr());
case UO_Plus:
  // The result is just the value.
  return Visit(E->getSubExpr());
case UO_Minus: {
  if (!Visit(E->getSubExpr()))
    return false;
  if (!Result.isInt()) return Error(E);
  const APSInt &Value = Result.getInt();
  if (Value.isSigned() && Value.isMinSignedValue() && E->canOverflow() &&
      !HandleOverflow(Info, E, -Value.extend(Value.getBitWidth() + 1),
                      E->getType()))
    return false;
  return Success(-Value, E);
}
case UO_Not: {
  if (!Visit(E->getSubExpr()))
    return false;
  if (!Result.isInt()) return Error(E);
  return Success(~Result.getInt(), E);
}
case UO_LNot: {
  bool bres;
  if (!EvaluateAsBooleanCondition(E->getSubExpr(), bres, Info))
    return false;
  return Success(!bres, E);
}
}
8938}

8940/// HandleCast - This is used to evaluate implicit or explicit casts where the
8941/// result type is integer.
8942bool IntExprEvaluator::VisitCastExpr(const CastExpr *E) {
const Expr *SubExpr = E->getSubExpr();
QualType DestType = E->getType();
QualType SrcType = SubExpr->getType();

switch (E->getCastKind()) {
case CK_BaseToDerived:
case CK_DerivedToBase:
case CK_UncheckedDerivedToBase:
case CK_Dynamic:
case CK_ToUnion:
case CK_ArrayToPointerDecay:
case CK_FunctionToPointerDecay:
case CK_NullToPointer:
case CK_NullToMemberPointer:
case CK_BaseToDerivedMemberPointer:
case CK_DerivedToBaseMemberPointer:
case CK_ReinterpretMemberPointer:
case CK_ConstructorConversion:
case CK_IntegralToPointer:
case CK_ToVoid:
case CK_VectorSplat:
case CK_IntegralToFloating:
case CK_FloatingCast:
case CK_CPointerToObjCPointerCast:
case CK_BlockPointerToObjCPointerCast:
case CK_AnyPointerToBlockPointerCast:
case CK_ObjCObjectLValueCast:
case CK_FloatingRealToComplex:
case CK_FloatingComplexToReal:
case CK_FloatingComplexCast:
case CK_FloatingComplexToIntegralComplex:
case CK_IntegralRealToComplex:
case CK_IntegralComplexCast:
case CK_IntegralComplexToFloatingComplex:
case CK_BuiltinFnToFnPtr:
case CK_ZeroToOCLEvent:
case CK_ZeroToOCLQueue:
case CK_NonAtomicToAtomic:
case CK_AddressSpaceConversion:
case CK_IntToOCLSampler:
  llvm_unreachable("invalid cast kind for integral value")::llvm::llvm_unreachable_internal("invalid cast kind for integral value"
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 8983);

case CK_BitCast:
case CK_Dependent:
case CK_LValueBitCast:
case CK_ARCProduceObject:
case CK_ARCConsumeObject:
case CK_ARCReclaimReturnedObject:
case CK_ARCExtendBlockObject:
case CK_CopyAndAutoreleaseBlockObject:
  return Error(E);

case CK_UserDefinedConversion:
case CK_LValueToRValue:
case CK_AtomicToNonAtomic:
case CK_NoOp:
  return ExprEvaluatorBaseTy::VisitCastExpr(E);

case CK_MemberPointerToBoolean:
case CK_PointerToBoolean:
case CK_IntegralToBoolean:
case CK_FloatingToBoolean:
case CK_BooleanToSignedIntegral:
case CK_FloatingComplexToBoolean:
case CK_IntegralComplexToBoolean: {
  bool BoolResult;
  if (!EvaluateAsBooleanCondition(SubExpr, BoolResult, Info))
    return false;
  uint64_t IntResult = BoolResult;
  if (BoolResult && E->getCastKind() == CK_BooleanToSignedIntegral)
    IntResult = (uint64_t)-1;
  return Success(IntResult, E);
}

case CK_IntegralCast: {
  if (!Visit(SubExpr))
    return false;

  if (!Result.isInt()) {
    // Allow casts of address-of-label differences if they are no-ops
    // or narrowing.  (The narrowing case isn't actually guaranteed to
    // be constant-evaluatable except in some narrow cases which are hard
    // to detect here.  We let it through on the assumption the user knows
    // what they are doing.)
    if (Result.isAddrLabelDiff())
      return Info.Ctx.getTypeSize(DestType) <= Info.Ctx.getTypeSize(SrcType);
    // Only allow casts of lvalues if they are lossless.
    return Info.Ctx.getTypeSize(DestType) == Info.Ctx.getTypeSize(SrcType);
  }

  return Success(HandleIntToIntCast(Info, E, DestType, SrcType,
                                    Result.getInt()), E);
}

case CK_PointerToIntegral: {
  CCEDiag(E, diag::note_constexpr_invalid_cast) << 2;

  LValue LV;
  if (!EvaluatePointer(SubExpr, LV, Info))
    return false;

  if (LV.getLValueBase()) {
    // Only allow based lvalue casts if they are lossless.
    // FIXME: Allow a larger integer size than the pointer size, and allow
    // narrowing back down to pointer width in subsequent integral casts.
    // FIXME: Check integer type's active bits, not its type size.
    if (Info.Ctx.getTypeSize(DestType) != Info.Ctx.getTypeSize(SrcType))
      return Error(E);

    LV.Designator.setInvalid();
    LV.moveInto(Result);
    return true;
  }

  uint64_t V;
  if (LV.isNullPointer())
    V = Info.Ctx.getTargetNullPointerValue(SrcType);
  else
    V = LV.getLValueOffset().getQuantity();

  APSInt AsInt = Info.Ctx.MakeIntValue(V, SrcType);
  return Success(HandleIntToIntCast(Info, E, DestType, SrcType, AsInt), E);
}

case CK_IntegralComplexToReal: {
  ComplexValue C;
  if (!EvaluateComplex(SubExpr, C, Info))
    return false;
  return Success(C.getComplexIntReal(), E);
}

case CK_FloatingToIntegral: {
  APFloat F(0.0);
  if (!EvaluateFloat(SubExpr, F, Info))
    return false;

  APSInt Value;
  if (!HandleFloatToIntCast(Info, E, SrcType, F, DestType, Value))
    return false;
  return Success(Value, E);
}
}

llvm_unreachable("unknown cast resulting in integral value")::llvm::llvm_unreachable_internal("unknown cast resulting in integral value"
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 9086);
9087}

9089bool IntExprEvaluator::VisitUnaryReal(const UnaryOperator *E) {
if (E->getSubExpr()->getType()->isAnyComplexType()) {
  ComplexValue LV;
  if (!EvaluateComplex(E->getSubExpr(), LV, Info))
    return false;
  if (!LV.isComplexInt())
    return Error(E);
  return Success(LV.getComplexIntReal(), E);
}

return Visit(E->getSubExpr());
9100}

9102bool IntExprEvaluator::VisitUnaryImag(const UnaryOperator *E) {
if (E->getSubExpr()->getType()->isComplexIntegerType()) {
  ComplexValue LV;
  if (!EvaluateComplex(E->getSubExpr(), LV, Info))
    return false;
  if (!LV.isComplexInt())
    return Error(E);
  return Success(LV.getComplexIntImag(), E);
}

VisitIgnoredValue(E->getSubExpr());
return Success(0, E);
9114}

9116bool IntExprEvaluator::VisitSizeOfPackExpr(const SizeOfPackExpr *E) {
return Success(E->getPackLength(), E);
9118}

9120bool IntExprEvaluator::VisitCXXNoexceptExpr(const CXXNoexceptExpr *E) {
return Success(E->getValue(), E);
9122}

9124//===----------------------------------------------------------------------===//
9125// Float Evaluation
9126//===----------------------------------------------------------------------===//

9128namespace {
9129class FloatExprEvaluator
: public ExprEvaluatorBase<FloatExprEvaluator> {
APFloat &Result;
9132public:
FloatExprEvaluator(EvalInfo &info, APFloat &result)
  : ExprEvaluatorBaseTy(info), Result(result) {}

bool Success(const APValue &V, const Expr *e) {
  Result = V.getFloat();
  return true;
}

bool ZeroInitialization(const Expr *E) {
  Result = APFloat::getZero(Info.Ctx.getFloatTypeSemantics(E->getType()));
  return true;
}

bool VisitCallExpr(const CallExpr *E);

bool VisitUnaryOperator(const UnaryOperator *E);
bool VisitBinaryOperator(const BinaryOperator *E);
bool VisitFloatingLiteral(const FloatingLiteral *E);
bool VisitCastExpr(const CastExpr *E);

bool VisitUnaryReal(const UnaryOperator *E);
bool VisitUnaryImag(const UnaryOperator *E);

// FIXME: Missing: array subscript of vector, member of vector
9157};
9158} // end anonymous namespace

9160static bool EvaluateFloat(const Expr* E, APFloat& Result, EvalInfo &Info) {
assert(E->isRValue() && E->getType()->isRealFloatingType())(static_cast <bool> (E->isRValue() && E->
getType()->isRealFloatingType()) ? void (0) : __assert_fail
 ("E->isRValue() && E->getType()->isRealFloatingType()"
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 9161, __extension__ __PRETTY_FUNCTION__));
return FloatExprEvaluator(Info, Result).Visit(E);
9163}

9165static bool TryEvaluateBuiltinNaN(const ASTContext &Context,
                                QualType ResultTy,
                                const Expr *Arg,
                                bool SNaN,
                                llvm::APFloat &Result) {
const StringLiteral *S = dyn_cast<StringLiteral>(Arg->IgnoreParenCasts());
if (!S) return false;

const llvm::fltSemantics &Sem = Context.getFloatTypeSemantics(ResultTy);

llvm::APInt fill;

// Treat empty strings as if they were zero.
if (S->getString().empty())
  fill = llvm::APInt(32, 0);
else if (S->getString().getAsInteger(0, fill))
  return false;

if (Context.getTargetInfo().isNan2008()) {
  if (SNaN)
    Result = llvm::APFloat::getSNaN(Sem, false, &fill);
  else
    Result = llvm::APFloat::getQNaN(Sem, false, &fill);
} else {
  // Prior to IEEE 754-2008, architectures were allowed to choose whether
  // the first bit of their significand was set for qNaN or sNaN. MIPS chose
  // a different encoding to what became a standard in 2008, and for pre-
  // 2008 revisions, MIPS interpreted sNaN-2008 as qNan and qNaN-2008 as
  // sNaN. This is now known as "legacy NaN" encoding.
  if (SNaN)
    Result = llvm::APFloat::getQNaN(Sem, false, &fill);
  else
    Result = llvm::APFloat::getSNaN(Sem, false, &fill);
}

return true;
9201}

9203bool FloatExprEvaluator::VisitCallExpr(const CallExpr *E) {
switch (E->getBuiltinCallee()) {
default:
  return ExprEvaluatorBaseTy::VisitCallExpr(E);

case Builtin::BI__builtin_huge_val:
case Builtin::BI__builtin_huge_valf:
case Builtin::BI__builtin_huge_vall:
case Builtin::BI__builtin_huge_valf128:
case Builtin::BI__builtin_inf:
case Builtin::BI__builtin_inff:
case Builtin::BI__builtin_infl:
case Builtin::BI__builtin_inff128: {
  const llvm::fltSemantics &Sem =
    Info.Ctx.getFloatTypeSemantics(E->getType());
  Result = llvm::APFloat::getInf(Sem);
  return true;
}

case Builtin::BI__builtin_nans:
case Builtin::BI__builtin_nansf:
case Builtin::BI__builtin_nansl:
case Builtin::BI__builtin_nansf128:
  if (!TryEvaluateBuiltinNaN(Info.Ctx, E->getType(), E->getArg(0),
                             true, Result))
    return Error(E);
  return true;

case Builtin::BI__builtin_nan:
case Builtin::BI__builtin_nanf:
case Builtin::BI__builtin_nanl:
case Builtin::BI__builtin_nanf128:
  // If this is __builtin_nan() turn this into a nan, otherwise we
  // can't constant fold it.
  if (!TryEvaluateBuiltinNaN(Info.Ctx, E->getType(), E->getArg(0),
                             false, Result))
    return Error(E);
  return true;

case Builtin::BI__builtin_fabs:
case Builtin::BI__builtin_fabsf:
case Builtin::BI__builtin_fabsl:
case Builtin::BI__builtin_fabsf128:
  if (!EvaluateFloat(E->getArg(0), Result, Info))
    return false;

  if (Result.isNegative())
    Result.changeSign();
  return true;

// FIXME: Builtin::BI__builtin_powi
// FIXME: Builtin::BI__builtin_powif
// FIXME: Builtin::BI__builtin_powil

case Builtin::BI__builtin_copysign:
case Builtin::BI__builtin_copysignf:
case Builtin::BI__builtin_copysignl:
case Builtin::BI__builtin_copysignf128: {
  APFloat RHS(0.);
  if (!EvaluateFloat(E->getArg(0), Result, Info) ||
      !EvaluateFloat(E->getArg(1), RHS, Info))
    return false;
  Result.copySign(RHS);
  return true;
}
}
9269}

9271bool FloatExprEvaluator::VisitUnaryReal(const UnaryOperator *E) {
if (E->getSubExpr()->getType()->isAnyComplexType()) {
  ComplexValue CV;
  if (!EvaluateComplex(E->getSubExpr(), CV, Info))
    return false;
  Result = CV.FloatReal;
  return true;
}

return Visit(E->getSubExpr());
9281}

9283bool FloatExprEvaluator::VisitUnaryImag(const UnaryOperator *E) {
if (E->getSubExpr()->getType()->isAnyComplexType()) {
  ComplexValue CV;
  if (!EvaluateComplex(E->getSubExpr(), CV, Info))
    return false;
  Result = CV.FloatImag;
  return true;
}

VisitIgnoredValue(E->getSubExpr());
const llvm::fltSemantics &Sem = Info.Ctx.getFloatTypeSemantics(E->getType());
Result = llvm::APFloat::getZero(Sem);
return true;
9296}

9298bool FloatExprEvaluator::VisitUnaryOperator(const UnaryOperator *E) {
switch (E->getOpcode()) {
default: return Error(E);
case UO_Plus:
  return EvaluateFloat(E->getSubExpr(), Result, Info);
case UO_Minus:
  if (!EvaluateFloat(E->getSubExpr(), Result, Info))
    return false;
  Result.changeSign();
  return true;
}
9309}

9311bool FloatExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) {
if (E->isPtrMemOp() || E->isAssignmentOp() || E->getOpcode() == BO_Comma)
  return ExprEvaluatorBaseTy::VisitBinaryOperator(E);

APFloat RHS(0.0);
bool LHSOK = EvaluateFloat(E->getLHS(), Result, Info);
if (!LHSOK && !Info.noteFailure())
  return false;
return EvaluateFloat(E->getRHS(), RHS, Info) && LHSOK &&
       handleFloatFloatBinOp(Info, E, Result, E->getOpcode(), RHS);
9321}

9323bool FloatExprEvaluator::VisitFloatingLiteral(const FloatingLiteral *E) {
Result = E->getValue();
return true;
9326}

9328bool FloatExprEvaluator::VisitCastExpr(const CastExpr *E) {
const Expr* SubExpr = E->getSubExpr();

switch (E->getCastKind()) {
default:
  return ExprEvaluatorBaseTy::VisitCastExpr(E);

case CK_IntegralToFloating: {
  APSInt IntResult;
  return EvaluateInteger(SubExpr, IntResult, Info) &&
         HandleIntToFloatCast(Info, E, SubExpr->getType(), IntResult,
                              E->getType(), Result);
}

case CK_FloatingCast: {
  if (!Visit(SubExpr))
    return false;
  return HandleFloatToFloatCast(Info, E, SubExpr->getType(), E->getType(),
                                Result);
}

case CK_FloatingComplexToReal: {
  ComplexValue V;
  if (!EvaluateComplex(SubExpr, V, Info))
    return false;
  Result = V.getComplexFloatReal();
  return true;
}
}
9357}

9359//===----------------------------------------------------------------------===//
9360// Complex Evaluation (for float and integer)
9361//===----------------------------------------------------------------------===//

9363namespace {
9364class ComplexExprEvaluator
: public ExprEvaluatorBase<ComplexExprEvaluator> {
ComplexValue &Result;

9368public:
ComplexExprEvaluator(EvalInfo &info, ComplexValue &Result)
  : ExprEvaluatorBaseTy(info), Result(Result) {}

bool Success(const APValue &V, const Expr *e) {
  Result.setFrom(V);
  return true;
}

bool ZeroInitialization(const Expr *E);

//===--------------------------------------------------------------------===//
//                            Visitor Methods
//===--------------------------------------------------------------------===//

bool VisitImaginaryLiteral(const ImaginaryLiteral *E);
bool VisitCastExpr(const CastExpr *E);
bool VisitBinaryOperator(const BinaryOperator *E);
bool VisitUnaryOperator(const UnaryOperator *E);
bool VisitInitListExpr(const InitListExpr *E);
9388};
9389} // end anonymous namespace

9391static bool EvaluateComplex(const Expr *E, ComplexValue &Result,
                          EvalInfo &Info) {
assert(E->isRValue() && E->getType()->isAnyComplexType())(static_cast <bool> (E->isRValue() && E->
getType()->isAnyComplexType()) ? void (0) : __assert_fail (
"E->isRValue() && E->getType()->isAnyComplexType()"
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 9393, __extension__ __PRETTY_FUNCTION__));
return ComplexExprEvaluator(Info, Result).Visit(E);
9395}

9397bool ComplexExprEvaluator::ZeroInitialization(const Expr *E) {
QualType ElemTy = E->getType()->castAs<ComplexType>()->getElementType();
if (ElemTy->isRealFloatingType()) {
  Result.makeComplexFloat();
  APFloat Zero = APFloat::getZero(Info.Ctx.getFloatTypeSemantics(ElemTy));
  Result.FloatReal = Zero;
  Result.FloatImag = Zero;
} else {
  Result.makeComplexInt();
  APSInt Zero = Info.Ctx.MakeIntValue(0, ElemTy);
  Result.IntReal = Zero;
  Result.IntImag = Zero;
}
return true;
9411}

9413bool ComplexExprEvaluator::VisitImaginaryLiteral(const ImaginaryLiteral *E) {
const Expr* SubExpr = E->getSubExpr();

if (SubExpr->getType()->isRealFloatingType()) {
  Result.makeComplexFloat();
  APFloat &Imag = Result.FloatImag;
  if (!EvaluateFloat(SubExpr, Imag, Info))
    return false;

  Result.FloatReal = APFloat(Imag.getSemantics());
  return true;
} else {
  assert(SubExpr->getType()->isIntegerType() &&(static_cast <bool> (SubExpr->getType()->isIntegerType
() && "Unexpected imaginary literal.") ? void (0) : __assert_fail
 ("SubExpr->getType()->isIntegerType() && \"Unexpected imaginary literal.\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 9426, __extension__ __PRETTY_FUNCTION__))
         "Unexpected imaginary literal.")(static_cast <bool> (SubExpr->getType()->isIntegerType
() && "Unexpected imaginary literal.") ? void (0) : __assert_fail
 ("SubExpr->getType()->isIntegerType() && \"Unexpected imaginary literal.\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 9426, __extension__ __PRETTY_FUNCTION__));

  Result.makeComplexInt();
  APSInt &Imag = Result.IntImag;
  if (!EvaluateInteger(SubExpr, Imag, Info))
    return false;

  Result.IntReal = APSInt(Imag.getBitWidth(), !Imag.isSigned());
  return true;
}
9436}

9438bool ComplexExprEvaluator::VisitCastExpr(const CastExpr *E) {

switch (E->getCastKind()) {
case CK_BitCast:
case CK_BaseToDerived:
case CK_DerivedToBase:
case CK_UncheckedDerivedToBase:
case CK_Dynamic:
case CK_ToUnion:
case CK_ArrayToPointerDecay:
case CK_FunctionToPointerDecay:
case CK_NullToPointer:
case CK_NullToMemberPointer:
case CK_BaseToDerivedMemberPointer:
case CK_DerivedToBaseMemberPointer:
case CK_MemberPointerToBoolean:
case CK_ReinterpretMemberPointer:
case CK_ConstructorConversion:
case CK_IntegralToPointer:
case CK_PointerToIntegral:
case CK_PointerToBoolean:
case CK_ToVoid:
case CK_VectorSplat:
case CK_IntegralCast:
case CK_BooleanToSignedIntegral:
case CK_IntegralToBoolean:
case CK_IntegralToFloating:
case CK_FloatingToIntegral:
case CK_FloatingToBoolean:
case CK_FloatingCast:
case CK_CPointerToObjCPointerCast:
case CK_BlockPointerToObjCPointerCast:
case CK_AnyPointerToBlockPointerCast:
case CK_ObjCObjectLValueCast:
case CK_FloatingComplexToReal:
case CK_FloatingComplexToBoolean:
case CK_IntegralComplexToReal:
case CK_IntegralComplexToBoolean:
case CK_ARCProduceObject:
case CK_ARCConsumeObject:
case CK_ARCReclaimReturnedObject:
case CK_ARCExtendBlockObject:
case CK_CopyAndAutoreleaseBlockObject:
case CK_BuiltinFnToFnPtr:
case CK_ZeroToOCLEvent:
case CK_ZeroToOCLQueue:
case CK_NonAtomicToAtomic:
case CK_AddressSpaceConversion:
case CK_IntToOCLSampler:
  llvm_unreachable("invalid cast kind for complex value")::llvm::llvm_unreachable_internal("invalid cast kind for complex value"
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 9487);

case CK_LValueToRValue:
case CK_AtomicToNonAtomic:
case CK_NoOp:
  return ExprEvaluatorBaseTy::VisitCastExpr(E);

case CK_Dependent:
case CK_LValueBitCast:
case CK_UserDefinedConversion:
  return Error(E);

case CK_FloatingRealToComplex: {
  APFloat &Real = Result.FloatReal;
  if (!EvaluateFloat(E->getSubExpr(), Real, Info))
    return false;

  Result.makeComplexFloat();
  Result.FloatImag = APFloat(Real.getSemantics());
  return true;
}

case CK_FloatingComplexCast: {
  if (!Visit(E->getSubExpr()))
    return false;

  QualType To = E->getType()->getAs<ComplexType>()->getElementType();
  QualType From
    = E->getSubExpr()->getType()->getAs<ComplexType>()->getElementType();

  return HandleFloatToFloatCast(Info, E, From, To, Result.FloatReal) &&
         HandleFloatToFloatCast(Info, E, From, To, Result.FloatImag);
}

case CK_FloatingComplexToIntegralComplex: {
  if (!Visit(E->getSubExpr()))
    return false;

  QualType To = E->getType()->getAs<ComplexType>()->getElementType();
  QualType From
    = E->getSubExpr()->getType()->getAs<ComplexType>()->getElementType();
  Result.makeComplexInt();
  return HandleFloatToIntCast(Info, E, From, Result.FloatReal,
                              To, Result.IntReal) &&
         HandleFloatToIntCast(Info, E, From, Result.FloatImag,
                              To, Result.IntImag);
}

case CK_IntegralRealToComplex: {
  APSInt &Real = Result.IntReal;
  if (!EvaluateInteger(E->getSubExpr(), Real, Info))
    return false;

  Result.makeComplexInt();
  Result.IntImag = APSInt(Real.getBitWidth(), !Real.isSigned());
  return true;
}

case CK_IntegralComplexCast: {
  if (!Visit(E->getSubExpr()))
    return false;

  QualType To = E->getType()->getAs<ComplexType>()->getElementType();
  QualType From
    = E->getSubExpr()->getType()->getAs<ComplexType>()->getElementType();

  Result.IntReal = HandleIntToIntCast(Info, E, To, From, Result.IntReal);
  Result.IntImag = HandleIntToIntCast(Info, E, To, From, Result.IntImag);
  return true;
}

case CK_IntegralComplexToFloatingComplex: {
  if (!Visit(E->getSubExpr()))
    return false;

  QualType To = E->getType()->castAs<ComplexType>()->getElementType();
  QualType From
    = E->getSubExpr()->getType()->castAs<ComplexType>()->getElementType();
  Result.makeComplexFloat();
  return HandleIntToFloatCast(Info, E, From, Result.IntReal,
                              To, Result.FloatReal) &&
         HandleIntToFloatCast(Info, E, From, Result.IntImag,
                              To, Result.FloatImag);
}
}

llvm_unreachable("unknown cast resulting in complex value")::llvm::llvm_unreachable_internal("unknown cast resulting in complex value"
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 9573);
9574}

9576bool ComplexExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) {
if (E->isPtrMemOp() || E->isAssignmentOp() || E->getOpcode() == BO_Comma)
  return ExprEvaluatorBaseTy::VisitBinaryOperator(E);

// Track whether the LHS or RHS is real at the type system level. When this is
// the case we can simplify our evaluation strategy.
bool LHSReal = false, RHSReal = false;

bool LHSOK;
if (E->getLHS()->getType()->isRealFloatingType()) {
  LHSReal = true;
  APFloat &Real = Result.FloatReal;
  LHSOK = EvaluateFloat(E->getLHS(), Real, Info);
  if (LHSOK) {
    Result.makeComplexFloat();
    Result.FloatImag = APFloat(Real.getSemantics());
  }
} else {
  LHSOK = Visit(E->getLHS());
}
if (!LHSOK && !Info.noteFailure())
  return false;

ComplexValue RHS;
if (E->getRHS()->getType()->isRealFloatingType()) {
  RHSReal = true;
  APFloat &Real = RHS.FloatReal;
  if (!EvaluateFloat(E->getRHS(), Real, Info) || !LHSOK)
    return false;
  RHS.makeComplexFloat();
  RHS.FloatImag = APFloat(Real.getSemantics());
} else if (!EvaluateComplex(E->getRHS(), RHS, Info) || !LHSOK)
  return false;

assert(!(LHSReal && RHSReal) &&(static_cast <bool> (!(LHSReal && RHSReal) &&
 "Cannot have both operands of a complex operation be real.")
 ? void (0) : __assert_fail ("!(LHSReal && RHSReal) && \"Cannot have both operands of a complex operation be real.\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 9611, __extension__ __PRETTY_FUNCTION__))
       "Cannot have both operands of a complex operation be real.")(static_cast <bool> (!(LHSReal && RHSReal) &&
 "Cannot have both operands of a complex operation be real.")
 ? void (0) : __assert_fail ("!(LHSReal && RHSReal) && \"Cannot have both operands of a complex operation be real.\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 9611, __extension__ __PRETTY_FUNCTION__));
switch (E->getOpcode()) {
default: return Error(E);
case BO_Add:
  if (Result.isComplexFloat()) {
    Result.getComplexFloatReal().add(RHS.getComplexFloatReal(),
                                     APFloat::rmNearestTiesToEven);
    if (LHSReal)
      Result.getComplexFloatImag() = RHS.getComplexFloatImag();
    else if (!RHSReal)
      Result.getComplexFloatImag().add(RHS.getComplexFloatImag(),
                                       APFloat::rmNearestTiesToEven);
  } else {
    Result.getComplexIntReal() += RHS.getComplexIntReal();
    Result.getComplexIntImag() += RHS.getComplexIntImag();
  }
  break;
case BO_Sub:
  if (Result.isComplexFloat()) {
    Result.getComplexFloatReal().subtract(RHS.getComplexFloatReal(),
                                          APFloat::rmNearestTiesToEven);
    if (LHSReal) {
      Result.getComplexFloatImag() = RHS.getComplexFloatImag();
      Result.getComplexFloatImag().changeSign();
    } else if (!RHSReal) {
      Result.getComplexFloatImag().subtract(RHS.getComplexFloatImag(),
                                            APFloat::rmNearestTiesToEven);
    }
  } else {
    Result.getComplexIntReal() -= RHS.getComplexIntReal();
    Result.getComplexIntImag() -= RHS.getComplexIntImag();
  }
  break;
case BO_Mul:
  if (Result.isComplexFloat()) {
    // This is an implementation of complex multiplication according to the
    // constraints laid out in C11 Annex G. The implemention uses the
    // following naming scheme:
    //   (a + ib) * (c + id)
    ComplexValue LHS = Result;
    APFloat &A = LHS.getComplexFloatReal();
    APFloat &B = LHS.getComplexFloatImag();
    APFloat &C = RHS.getComplexFloatReal();
    APFloat &D = RHS.getComplexFloatImag();
    APFloat &ResR = Result.getComplexFloatReal();
    APFloat &ResI = Result.getComplexFloatImag();
    if (LHSReal) {
      assert(!RHSReal && "Cannot have two real operands for a complex op!")(static_cast <bool> (!RHSReal && "Cannot have two real operands for a complex op!"
) ? void (0) : __assert_fail ("!RHSReal && \"Cannot have two real operands for a complex op!\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 9658, __extension__ __PRETTY_FUNCTION__));
      ResR = A * C;
      ResI = A * D;
    } else if (RHSReal) {
      ResR = C * A;
      ResI = C * B;
    } else {
      // In the fully general case, we need to handle NaNs and infinities
      // robustly.
      APFloat AC = A * C;
      APFloat BD = B * D;
      APFloat AD = A * D;
      APFloat BC = B * C;
      ResR = AC - BD;
      ResI = AD + BC;
      if (ResR.isNaN() && ResI.isNaN()) {
        bool Recalc = false;
        if (A.isInfinity() || B.isInfinity()) {
          A = APFloat::copySign(
              APFloat(A.getSemantics(), A.isInfinity() ? 1 : 0), A);
          B = APFloat::copySign(
              APFloat(B.getSemantics(), B.isInfinity() ? 1 : 0), B);
          if (C.isNaN())
            C = APFloat::copySign(APFloat(C.getSemantics()), C);
          if (D.isNaN())
            D = APFloat::copySign(APFloat(D.getSemantics()), D);
          Recalc = true;
        }
        if (C.isInfinity() || D.isInfinity()) {
          C = APFloat::copySign(
              APFloat(C.getSemantics(), C.isInfinity() ? 1 : 0), C);
          D = APFloat::copySign(
              APFloat(D.getSemantics(), D.isInfinity() ? 1 : 0), D);
          if (A.isNaN())
            A = APFloat::copySign(APFloat(A.getSemantics()), A);
          if (B.isNaN())
            B = APFloat::copySign(APFloat(B.getSemantics()), B);
          Recalc = true;
        }
        if (!Recalc && (AC.isInfinity() || BD.isInfinity() ||
                        AD.isInfinity() || BC.isInfinity())) {
          if (A.isNaN())
            A = APFloat::copySign(APFloat(A.getSemantics()), A);
          if (B.isNaN())
            B = APFloat::copySign(APFloat(B.getSemantics()), B);
          if (C.isNaN())
            C = APFloat::copySign(APFloat(C.getSemantics()), C);
          if (D.isNaN())
            D = APFloat::copySign(APFloat(D.getSemantics()), D);
          Recalc = true;
        }
        if (Recalc) {
          ResR = APFloat::getInf(A.getSemantics()) * (A * C - B * D);
          ResI = APFloat::getInf(A.getSemantics()) * (A * D + B * C);
        }
      }
    }
  } else {
    ComplexValue LHS = Result;
    Result.getComplexIntReal() =
      (LHS.getComplexIntReal() * RHS.getComplexIntReal() -
       LHS.getComplexIntImag() * RHS.getComplexIntImag());
    Result.getComplexIntImag() =
      (LHS.getComplexIntReal() * RHS.getComplexIntImag() +
       LHS.getComplexIntImag() * RHS.getComplexIntReal());
  }
  break;
case BO_Div:
  if (Result.isComplexFloat()) {
    // This is an implementation of complex division according to the
    // constraints laid out in C11 Annex G. The implemention uses the
    // following naming scheme:
    //   (a + ib) / (c + id)
    ComplexValue LHS = Result;
    APFloat &A = LHS.getComplexFloatReal();
    APFloat &B = LHS.getComplexFloatImag();
    APFloat &C = RHS.getComplexFloatReal();
    APFloat &D = RHS.getComplexFloatImag();
    APFloat &ResR = Result.getComplexFloatReal();
    APFloat &ResI = Result.getComplexFloatImag();
    if (RHSReal) {
      ResR = A / C;
      ResI = B / C;
    } else {
      if (LHSReal) {
        // No real optimizations we can do here, stub out with zero.
        B = APFloat::getZero(A.getSemantics());
      }
      int DenomLogB = 0;
      APFloat MaxCD = maxnum(abs(C), abs(D));
      if (MaxCD.isFinite()) {
        DenomLogB = ilogb(MaxCD);
        C = scalbn(C, -DenomLogB, APFloat::rmNearestTiesToEven);
        D = scalbn(D, -DenomLogB, APFloat::rmNearestTiesToEven);
      }
      APFloat Denom = C * C + D * D;
      ResR = scalbn((A * C + B * D) / Denom, -DenomLogB,
                    APFloat::rmNearestTiesToEven);
      ResI = scalbn((B * C - A * D) / Denom, -DenomLogB,
                    APFloat::rmNearestTiesToEven);
      if (ResR.isNaN() && ResI.isNaN()) {
        if (Denom.isPosZero() && (!A.isNaN() || !B.isNaN())) {
          ResR = APFloat::getInf(ResR.getSemantics(), C.isNegative()) * A;
          ResI = APFloat::getInf(ResR.getSemantics(), C.isNegative()) * B;
        } else if ((A.isInfinity() || B.isInfinity()) && C.isFinite() &&
                   D.isFinite()) {
          A = APFloat::copySign(
              APFloat(A.getSemantics(), A.isInfinity() ? 1 : 0), A);
          B = APFloat::copySign(
              APFloat(B.getSemantics(), B.isInfinity() ? 1 : 0), B);
          ResR = APFloat::getInf(ResR.getSemantics()) * (A * C + B * D);
          ResI = APFloat::getInf(ResI.getSemantics()) * (B * C - A * D);
        } else if (MaxCD.isInfinity() && A.isFinite() && B.isFinite()) {
          C = APFloat::copySign(
              APFloat(C.getSemantics(), C.isInfinity() ? 1 : 0), C);
          D = APFloat::copySign(
              APFloat(D.getSemantics(), D.isInfinity() ? 1 : 0), D);
          ResR = APFloat::getZero(ResR.getSemantics()) * (A * C + B * D);
          ResI = APFloat::getZero(ResI.getSemantics()) * (B * C - A * D);
        }
      }
    }
  } else {
    if (RHS.getComplexIntReal() == 0 && RHS.getComplexIntImag() == 0)
      return Error(E, diag::note_expr_divide_by_zero);

    ComplexValue LHS = Result;
    APSInt Den = RHS.getComplexIntReal() * RHS.getComplexIntReal() +
      RHS.getComplexIntImag() * RHS.getComplexIntImag();
    Result.getComplexIntReal() =
      (LHS.getComplexIntReal() * RHS.getComplexIntReal() +
       LHS.getComplexIntImag() * RHS.getComplexIntImag()) / Den;
    Result.getComplexIntImag() =
      (LHS.getComplexIntImag() * RHS.getComplexIntReal() -
       LHS.getComplexIntReal() * RHS.getComplexIntImag()) / Den;
  }
  break;
}

return true;
9798}

9800bool ComplexExprEvaluator::VisitUnaryOperator(const UnaryOperator *E) {
// Get the operand value into 'Result'.
if (!Visit(E->getSubExpr()))
  return false;

switch (E->getOpcode()) {
default:
  return Error(E);
case UO_Extension:
  return true;
case UO_Plus:
  // The result is always just the subexpr.
  return true;
case UO_Minus:
  if (Result.isComplexFloat()) {
    Result.getComplexFloatReal().changeSign();
    Result.getComplexFloatImag().changeSign();
  }
  else {
    Result.getComplexIntReal() = -Result.getComplexIntReal();
    Result.getComplexIntImag() = -Result.getComplexIntImag();
  }
  return true;
case UO_Not:
  if (Result.isComplexFloat())
    Result.getComplexFloatImag().changeSign();
  else
    Result.getComplexIntImag() = -Result.getComplexIntImag();
  return true;
}
9830}

9832bool ComplexExprEvaluator::VisitInitListExpr(const InitListExpr *E) {
if (E->getNumInits() == 2) {
  if (E->getType()->isComplexType()) {
    Result.makeComplexFloat();
    if (!EvaluateFloat(E->getInit(0), Result.FloatReal, Info))
      return false;
    if (!EvaluateFloat(E->getInit(1), Result.FloatImag, Info))
      return false;
  } else {
    Result.makeComplexInt();
    if (!EvaluateInteger(E->getInit(0), Result.IntReal, Info))
      return false;
    if (!EvaluateInteger(E->getInit(1), Result.IntImag, Info))
      return false;
  }
  return true;
}
return ExprEvaluatorBaseTy::VisitInitListExpr(E);
9850}

9852//===----------------------------------------------------------------------===//
9853// Atomic expression evaluation, essentially just handling the NonAtomicToAtomic
9854// implicit conversion.
9855//===----------------------------------------------------------------------===//

9857namespace {
9858class AtomicExprEvaluator :
  public ExprEvaluatorBase<AtomicExprEvaluator> {
const LValue *This;
APValue &Result;
9862public:
AtomicExprEvaluator(EvalInfo &Info, const LValue *This, APValue &Result)
    : ExprEvaluatorBaseTy(Info), This(This), Result(Result) {}

bool Success(const APValue &V, const Expr *E) {
  Result = V;
  return true;
}

bool ZeroInitialization(const Expr *E) {
  ImplicitValueInitExpr VIE(
      E->getType()->castAs<AtomicType>()->getValueType());
  // For atomic-qualified class (and array) types in C++, initialize the
  // _Atomic-wrapped subobject directly, in-place.
  return This ? EvaluateInPlace(Result, Info, *This, &VIE)
              : Evaluate(Result, Info, &VIE);
}

bool VisitCastExpr(const CastExpr *E) {
  switch (E->getCastKind()) {
  default:
    return ExprEvaluatorBaseTy::VisitCastExpr(E);
  case CK_NonAtomicToAtomic:
    return This ? EvaluateInPlace(Result, Info, *This, E->getSubExpr())
                : Evaluate(Result, Info, E->getSubExpr());
  }
}
9889};
9890} // end anonymous namespace

9892static bool EvaluateAtomic(const Expr *E, const LValue *This, APValue &Result,
                         EvalInfo &Info) {
assert(E->isRValue() && E->getType()->isAtomicType())(static_cast <bool> (E->isRValue() && E->
getType()->isAtomicType()) ? void (0) : __assert_fail ("E->isRValue() && E->getType()->isAtomicType()"
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 9894, __extension__ __PRETTY_FUNCTION__));
return AtomicExprEvaluator(Info, This, Result).Visit(E);
9896}

9898//===----------------------------------------------------------------------===//
9899// Void expression evaluation, primarily for a cast to void on the LHS of a
9900// comma operator
9901//===----------------------------------------------------------------------===//

9903namespace {
9904class VoidExprEvaluator
: public ExprEvaluatorBase<VoidExprEvaluator> {
9906public:
VoidExprEvaluator(EvalInfo &Info) : ExprEvaluatorBaseTy(Info) {}

bool Success(const APValue &V, const Expr *e) { return true; }

bool ZeroInitialization(const Expr *E) { return true; }

bool VisitCastExpr(const CastExpr *E) {
  switch (E->getCastKind()) {
  default:
    return ExprEvaluatorBaseTy::VisitCastExpr(E);
  case CK_ToVoid:
    VisitIgnoredValue(E->getSubExpr());
    return true;
  }
}

bool VisitCallExpr(const CallExpr *E) {
  switch (E->getBuiltinCallee()) {
  default:
    return ExprEvaluatorBaseTy::VisitCallExpr(E);
  case Builtin::BI__assume:
  case Builtin::BI__builtin_assume:
    // The argument is not evaluated!
    return true;
  }
}
9933};
9934} // end anonymous namespace

9936static bool EvaluateVoid(const Expr *E, EvalInfo &Info) {
assert(E->isRValue() && E->getType()->isVoidType())(static_cast <bool> (E->isRValue() && E->
getType()->isVoidType()) ? void (0) : __assert_fail ("E->isRValue() && E->getType()->isVoidType()"
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 9937, __extension__ __PRETTY_FUNCTION__));
return VoidExprEvaluator(Info).Visit(E);
9939}

9941//===----------------------------------------------------------------------===//
9942// Top level Expr::EvaluateAsRValue method.
9943//===----------------------------------------------------------------------===//

9945static bool Evaluate(APValue &Result, EvalInfo &Info, const Expr *E) {
// In C, function designators are not lvalues, but we evaluate them as if they
// are.
QualType T = E->getType();
if (E->isGLValue() || T->isFunctionType()) {
  LValue LV;
  if (!EvaluateLValue(E, LV, Info))
    return false;
  LV.moveInto(Result);
} else if (T->isVectorType()) {
  if (!EvaluateVector(E, Result, Info))
    return false;
} else if (T->isIntegralOrEnumerationType()) {
  if (!IntExprEvaluator(Info, Result).Visit(E))
    return false;
} else if (T->hasPointerRepresentation()) {
  LValue LV;
  if (!EvaluatePointer(E, LV, Info))
    return false;
  LV.moveInto(Result);
} else if (T->isRealFloatingType()) {
  llvm::APFloat F(0.0);
  if (!EvaluateFloat(E, F, Info))
    return false;
  Result = APValue(F);
} else if (T->isAnyComplexType()) {
  ComplexValue C;
  if (!EvaluateComplex(E, C, Info))
    return false;
  C.moveInto(Result);
} else if (T->isMemberPointerType()) {
  MemberPtr P;
  if (!EvaluateMemberPointer(E, P, Info))
    return false;
  P.moveInto(Result);
  return true;
} else if (T->isArrayType()) {
  LValue LV;
  LV.set(E, Info.CurrentCall->Index);
  APValue &Value = Info.CurrentCall->createTemporary(E, false);
  if (!EvaluateArray(E, LV, Value, Info))
    return false;
  Result = Value;
} else if (T->isRecordType()) {
  LValue LV;
  LV.set(E, Info.CurrentCall->Index);
  APValue &Value = Info.CurrentCall->createTemporary(E, false);
  if (!EvaluateRecord(E, LV, Value, Info))
    return false;
  Result = Value;
} else if (T->isVoidType()) {
  if (!Info.getLangOpts().CPlusPlus11)
    Info.CCEDiag(E, diag::note_constexpr_nonliteral)
      << E->getType();
  if (!EvaluateVoid(E, Info))
    return false;
} else if (T->isAtomicType()) {
  QualType Unqual = T.getAtomicUnqualifiedType();
  if (Unqual->isArrayType() || Unqual->isRecordType()) {
    LValue LV;
    LV.set(E, Info.CurrentCall->Index);
    APValue &Value = Info.CurrentCall->createTemporary(E, false);
    if (!EvaluateAtomic(E, &LV, Value, Info))
      return false;
  } else {
    if (!EvaluateAtomic(E, nullptr, Result, Info))
      return false;
  }
} else if (Info.getLangOpts().CPlusPlus11) {
  Info.FFDiag(E, diag::note_constexpr_nonliteral) << E->getType();
  return false;
} else {
  Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr);
  return false;
}

return true;
10022}

10024/// EvaluateInPlace - Evaluate an expression in-place in an APValue. In some
10025/// cases, the in-place evaluation is essential, since later initializers for
10026/// an object can indirectly refer to subobjects which were initialized earlier.
10027static bool EvaluateInPlace(APValue &Result, EvalInfo &Info, const LValue &This,
                          const Expr *E, bool AllowNonLiteralTypes) {
assert(!E->isValueDependent())(static_cast <bool> (!E->isValueDependent()) ? void (
0) : __assert_fail ("!E->isValueDependent()", "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 10029, __extension__ __PRETTY_FUNCTION__));

if (!AllowNonLiteralTypes && !CheckLiteralType(Info, E, &This))
  return false;

if (E->isRValue()) {
  // Evaluate arrays and record types in-place, so that later initializers can
  // refer to earlier-initialized members of the object.
  QualType T = E->getType();
  if (T->isArrayType())
    return EvaluateArray(E, This, Result, Info);
  else if (T->isRecordType())
    return EvaluateRecord(E, This, Result, Info);
  else if (T->isAtomicType()) {
    QualType Unqual = T.getAtomicUnqualifiedType();
    if (Unqual->isArrayType() || Unqual->isRecordType())
      return EvaluateAtomic(E, &This, Result, Info);
  }
}

// For any other type, in-place evaluation is unimportant.
return Evaluate(Result, Info, E);
10051}

10053/// EvaluateAsRValue - Try to evaluate this expression, performing an implicit
10054/// lvalue-to-rvalue cast if it is an lvalue.
10055static bool EvaluateAsRValue(EvalInfo &Info, const Expr *E, APValue &Result) {
if (E->getType().isNull())
  return false;

if (!CheckLiteralType(Info, E))
  return false;

if (!::Evaluate(Result, Info, E))
  return false;

if (E->isGLValue()) {
  LValue LV;
  LV.setFrom(Info.Ctx, Result);
  if (!handleLValueToRValueConversion(Info, E, E->getType(), LV, Result))
    return false;
}

// Check this core constant expression is a constant expression.
return CheckConstantExpression(Info, E->getExprLoc(), E->getType(), Result);
10074}

10076static bool FastEvaluateAsRValue(const Expr *Exp, Expr::EvalResult &Result,
                               const ASTContext &Ctx, bool &IsConst) {
// Fast-path evaluations of integer literals, since we sometimes see files
// containing vast quantities of these.
if (const IntegerLiteral *L = dyn_cast<IntegerLiteral>(Exp)) {
  Result.Val = APValue(APSInt(L->getValue(),
                              L->getType()->isUnsignedIntegerType()));
  IsConst = true;
  return true;
}

// This case should be rare, but we need to check it before we check on
// the type below.
if (Exp->getType().isNull()) {
  IsConst = false;
  return true;
}

// FIXME: Evaluating values of large array and record types can cause
// performance problems. Only do so in C++11 for now.
if (Exp->isRValue() && (Exp->getType()->isArrayType() ||
                        Exp->getType()->isRecordType()) &&
    !Ctx.getLangOpts().CPlusPlus11) {
  IsConst = false;
  return true;
}
return false;
10103}


10106/// EvaluateAsRValue - Return true if this is a constant which we can fold using
10107/// any crazy technique (that has nothing to do with language standards) that
10108/// we want to.  If this function returns true, it returns the folded constant
10109/// in Result. If this expression is a glvalue, an lvalue-to-rvalue conversion
10110/// will be applied to the result.
10111bool Expr::EvaluateAsRValue(EvalResult &Result, const ASTContext &Ctx) const {
bool IsConst;
if (FastEvaluateAsRValue(this, Result, Ctx, IsConst))
  return IsConst;

EvalInfo Info(Ctx, Result, EvalInfo::EM_IgnoreSideEffects);
return ::EvaluateAsRValue(Info, this, Result.Val);
10118}

10120bool Expr::EvaluateAsBooleanCondition(bool &Result,
                                    const ASTContext &Ctx) const {
EvalResult Scratch;
return EvaluateAsRValue(Scratch, Ctx) &&
       HandleConversionToBool(Scratch.Val, Result);
10125}

10127static bool hasUnacceptableSideEffect(Expr::EvalStatus &Result,
                                    Expr::SideEffectsKind SEK) {
return (SEK < Expr::SE_AllowSideEffects && Result.HasSideEffects) ||
       (SEK < Expr::SE_AllowUndefinedBehavior && Result.HasUndefinedBehavior);
10131}

10133bool Expr::EvaluateAsInt(APSInt &Result, const ASTContext &Ctx,
                       SideEffectsKind AllowSideEffects) const {
if (!getType()->isIntegralOrEnumerationType())
  return false;

EvalResult ExprResult;
if (!EvaluateAsRValue(ExprResult, Ctx) || !ExprResult.Val.isInt() ||
    hasUnacceptableSideEffect(ExprResult, AllowSideEffects))
  return false;

Result = ExprResult.Val.getInt();
return true;
10145}

10147bool Expr::EvaluateAsFloat(APFloat &Result, const ASTContext &Ctx,
                         SideEffectsKind AllowSideEffects) const {
if (!getType()->isRealFloatingType())
  return false;

EvalResult ExprResult;
if (!EvaluateAsRValue(ExprResult, Ctx) || !ExprResult.Val.isFloat() ||
    hasUnacceptableSideEffect(ExprResult, AllowSideEffects))
  return false;

Result = ExprResult.Val.getFloat();
return true;
10159}

10161bool Expr::EvaluateAsLValue(EvalResult &Result, const ASTContext &Ctx) const {
EvalInfo Info(Ctx, Result, EvalInfo::EM_ConstantFold);

LValue LV;
if (!EvaluateLValue(this, LV, Info) || Result.HasSideEffects ||
    !CheckLValueConstantExpression(Info, getExprLoc(),
                                   Ctx.getLValueReferenceType(getType()), LV))
  return false;

LV.moveInto(Result.Val);
return true;
10172}

10174bool Expr::EvaluateAsInitializer(APValue &Value, const ASTContext &Ctx,
                               const VarDecl *VD,
                          SmallVectorImpl<PartialDiagnosticAt> &Notes) const {
// FIXME: Evaluating initializers for large array and record types can cause
// performance problems. Only do so in C++11 for now.
if (isRValue() && (getType()->isArrayType() || getType()->isRecordType()) &&
    !Ctx.getLangOpts().CPlusPlus11)
  return false;

Expr::EvalStatus EStatus;
EStatus.Diag = &Notes;

EvalInfo InitInfo(Ctx, EStatus, VD->isConstexpr()
                                    ? EvalInfo::EM_ConstantExpression
                                    : EvalInfo::EM_ConstantFold);
InitInfo.setEvaluatingDecl(VD, Value);

LValue LVal;
LVal.set(VD);

// C++11 [basic.start.init]p2:
//  Variables with static storage duration or thread storage duration shall be
//  zero-initialized before any other initialization takes place.
// This behavior is not present in C.
if (Ctx.getLangOpts().CPlusPlus && !VD->hasLocalStorage() &&
    !VD->getType()->isReferenceType()) {
  ImplicitValueInitExpr VIE(VD->getType());
  if (!EvaluateInPlace(Value, InitInfo, LVal, &VIE,
                       /*AllowNonLiteralTypes=*/true))
    return false;
}

if (!EvaluateInPlace(Value, InitInfo, LVal, this,
                     /*AllowNonLiteralTypes=*/true) ||
    EStatus.HasSideEffects)
  return false;

return CheckConstantExpression(InitInfo, VD->getLocation(), VD->getType(),
                               Value);
10213}

10215/// isEvaluatable - Call EvaluateAsRValue to see if this expression can be
10216/// constant folded, but discard the result.
10217bool Expr::isEvaluatable(const ASTContext &Ctx, SideEffectsKind SEK) const {
EvalResult Result;
return EvaluateAsRValue(Result, Ctx) &&
       !hasUnacceptableSideEffect(Result, SEK);
10221}

10223APSInt Expr::EvaluateKnownConstInt(const ASTContext &Ctx,
                  SmallVectorImpl<PartialDiagnosticAt> *Diag) const {
EvalResult EvalResult;
EvalResult.Diag = Diag;
bool Result = EvaluateAsRValue(EvalResult, Ctx);
(void)Result;
assert(Result && "Could not evaluate expression")(static_cast <bool> (Result && "Could not evaluate expression"
) ? void (0) : __assert_fail ("Result && \"Could not evaluate expression\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 10229, __extension__ __PRETTY_FUNCTION__));
assert(EvalResult.Val.isInt() && "Expression did not evaluate to integer")(static_cast <bool> (EvalResult.Val.isInt() && "Expression did not evaluate to integer"
) ? void (0) : __assert_fail ("EvalResult.Val.isInt() && \"Expression did not evaluate to integer\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 10230, __extension__ __PRETTY_FUNCTION__));

return EvalResult.Val.getInt();
10233}

10235void Expr::EvaluateForOverflow(const ASTContext &Ctx) const {
bool IsConst;
EvalResult EvalResult;
if (!FastEvaluateAsRValue(this, EvalResult, Ctx, IsConst)) {
  EvalInfo Info(Ctx, EvalResult, EvalInfo::EM_EvaluateForOverflow);
  (void)::EvaluateAsRValue(Info, this, EvalResult.Val);
}
10242}

10244bool Expr::EvalResult::isGlobalLValue() const {
assert(Val.isLValue())(static_cast <bool> (Val.isLValue()) ? void (0) : __assert_fail
 ("Val.isLValue()", "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 10245, __extension__ __PRETTY_FUNCTION__));
return IsGlobalLValue(Val.getLValueBase());
10247}


10250/// isIntegerConstantExpr - this recursive routine will test if an expression is
10251/// an integer constant expression.

10253/// FIXME: Pass up a reason why! Invalid operation in i-c-e, division by zero,
10254/// comma, etc

10256// CheckICE - This function does the fundamental ICE checking: the returned
10257// ICEDiag contains an ICEKind indicating whether the expression is an ICE,
10258// and a (possibly null) SourceLocation indicating the location of the problem.
10259//
10260// Note that to reduce code duplication, this helper does no evaluation
10261// itself; the caller checks whether the expression is evaluatable, and
10262// in the rare cases where CheckICE actually cares about the evaluated
10263// value, it calls into Evaluate.

10265namespace {

10267enum ICEKind {
/// This expression is an ICE.
IK_ICE,
/// This expression is not an ICE, but if it isn't evaluated, it's
/// a legal subexpression for an ICE. This return value is used to handle
/// the comma operator in C99 mode, and non-constant subexpressions.
IK_ICEIfUnevaluated,
/// This expression is not an ICE, and is not a legal subexpression for one.
IK_NotICE
10276};

10278struct ICEDiag {
ICEKind Kind;
SourceLocation Loc;

ICEDiag(ICEKind IK, SourceLocation l) : Kind(IK), Loc(l) {}
10283};

10285}

10287static ICEDiag NoDiag() { return ICEDiag(IK_ICE, SourceLocation()); }

10289static ICEDiag Worst(ICEDiag A, ICEDiag B) { return A.Kind >= B.Kind ? A : B; }

10291static ICEDiag CheckEvalInICE(const Expr* E, const ASTContext &Ctx) {
Expr::EvalResult EVResult;
if (!E->EvaluateAsRValue(EVResult, Ctx) || EVResult.HasSideEffects ||
    !EVResult.Val.isInt())
  return ICEDiag(IK_NotICE, E->getLocStart());

return NoDiag();
10298}

10300static ICEDiag CheckICE(const Expr* E, const ASTContext &Ctx) {
assert(!E->isValueDependent() && "Should not see value dependent exprs!")(static_cast <bool> (!E->isValueDependent() &&
 "Should not see value dependent exprs!") ? void (0) : __assert_fail
 ("!E->isValueDependent() && \"Should not see value dependent exprs!\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 10301, __extension__ __PRETTY_FUNCTION__));
if (!E->getType()->isIntegralOrEnumerationType())
  return ICEDiag(IK_NotICE, E->getLocStart());

switch (E->getStmtClass()) {
10306#define ABSTRACT_STMT(Node)
10307#define STMT(Node, Base) case Expr::Node##Class:
10308#define EXPR(Node, Base)
10309#include "clang/AST/StmtNodes.inc"
case Expr::PredefinedExprClass:
case Expr::FloatingLiteralClass:
case Expr::ImaginaryLiteralClass:
case Expr::StringLiteralClass:
case Expr::ArraySubscriptExprClass:
case Expr::OMPArraySectionExprClass:
case Expr::MemberExprClass:
case Expr::CompoundAssignOperatorClass:
case Expr::CompoundLiteralExprClass:
case Expr::ExtVectorElementExprClass:
case Expr::DesignatedInitExprClass:
case Expr::ArrayInitLoopExprClass:
case Expr::ArrayInitIndexExprClass:
case Expr::NoInitExprClass:
case Expr::DesignatedInitUpdateExprClass:
case Expr::ImplicitValueInitExprClass:
case Expr::ParenListExprClass:
case Expr::VAArgExprClass:
case Expr::AddrLabelExprClass:
case Expr::StmtExprClass:
case Expr::CXXMemberCallExprClass:
case Expr::CUDAKernelCallExprClass:
case Expr::CXXDynamicCastExprClass:
case Expr::CXXTypeidExprClass:
case Expr::CXXUuidofExprClass:
case Expr::MSPropertyRefExprClass:
case Expr::MSPropertySubscriptExprClass:
case Expr::CXXNullPtrLiteralExprClass:
case Expr::UserDefinedLiteralClass:
case Expr::CXXThisExprClass:
case Expr::CXXThrowExprClass:
case Expr::CXXNewExprClass:
case Expr::CXXDeleteExprClass:
case Expr::CXXPseudoDestructorExprClass:
case Expr::UnresolvedLookupExprClass:
case Expr::TypoExprClass:
case Expr::DependentScopeDeclRefExprClass:
case Expr::CXXConstructExprClass:
case Expr::CXXInheritedCtorInitExprClass:
case Expr::CXXStdInitializerListExprClass:
case Expr::CXXBindTemporaryExprClass:
case Expr::ExprWithCleanupsClass:
case Expr::CXXTemporaryObjectExprClass:
case Expr::CXXUnresolvedConstructExprClass:
case Expr::CXXDependentScopeMemberExprClass:
case Expr::UnresolvedMemberExprClass:
case Expr::ObjCStringLiteralClass:
case Expr::ObjCBoxedExprClass:
case Expr::ObjCArrayLiteralClass:
case Expr::ObjCDictionaryLiteralClass:
case Expr::ObjCEncodeExprClass:
case Expr::ObjCMessageExprClass:
case Expr::ObjCSelectorExprClass:
case Expr::ObjCProtocolExprClass:
case Expr::ObjCIvarRefExprClass:
case Expr::ObjCPropertyRefExprClass:
case Expr::ObjCSubscriptRefExprClass:
case Expr::ObjCIsaExprClass:
case Expr::ObjCAvailabilityCheckExprClass:
case Expr::ShuffleVectorExprClass:
case Expr::ConvertVectorExprClass:
case Expr::BlockExprClass:
case Expr::NoStmtClass:
case Expr::OpaqueValueExprClass:
case Expr::PackExpansionExprClass:
case Expr::SubstNonTypeTemplateParmPackExprClass:
case Expr::FunctionParmPackExprClass:
case Expr::AsTypeExprClass:
case Expr::ObjCIndirectCopyRestoreExprClass:
case Expr::MaterializeTemporaryExprClass:
case Expr::PseudoObjectExprClass:
case Expr::AtomicExprClass:
case Expr::LambdaExprClass:
case Expr::CXXFoldExprClass:
case Expr::CoawaitExprClass:
case Expr::DependentCoawaitExprClass:
case Expr::CoyieldExprClass:
  return ICEDiag(IK_NotICE, E->getLocStart());

case Expr::InitListExprClass: {
  // C++03 [dcl.init]p13: If T is a scalar type, then a declaration of the
  // form "T x = { a };" is equivalent to "T x = a;".
  // Unless we're initializing a reference, T is a scalar as it is known to be
  // of integral or enumeration type.
  if (E->isRValue())
    if (cast<InitListExpr>(E)->getNumInits() == 1)
      return CheckICE(cast<InitListExpr>(E)->getInit(0), Ctx);
  return ICEDiag(IK_NotICE, E->getLocStart());
}

case Expr::SizeOfPackExprClass:
case Expr::GNUNullExprClass:
  // GCC considers the GNU __null value to be an integral constant expression.
  return NoDiag();

case Expr::SubstNonTypeTemplateParmExprClass:
  return
    CheckICE(cast<SubstNonTypeTemplateParmExpr>(E)->getReplacement(), Ctx);

case Expr::ParenExprClass:
  return CheckICE(cast<ParenExpr>(E)->getSubExpr(), Ctx);
case Expr::GenericSelectionExprClass:
  return CheckICE(cast<GenericSelectionExpr>(E)->getResultExpr(), Ctx);
case Expr::IntegerLiteralClass:
case Expr::CharacterLiteralClass:
case Expr::ObjCBoolLiteralExprClass:
case Expr::CXXBoolLiteralExprClass:
case Expr::CXXScalarValueInitExprClass:
case Expr::TypeTraitExprClass:
case Expr::ArrayTypeTraitExprClass:
case Expr::ExpressionTraitExprClass:
case Expr::CXXNoexceptExprClass:
  return NoDiag();
case Expr::CallExprClass:
case Expr::CXXOperatorCallExprClass: {
  // C99 6.6/3 allows function calls within unevaluated subexpressions of
  // constant expressions, but they can never be ICEs because an ICE cannot
  // contain an operand of (pointer to) function type.
  const CallExpr *CE = cast<CallExpr>(E);
  if (CE->getBuiltinCallee())
    return CheckEvalInICE(E, Ctx);
  return ICEDiag(IK_NotICE, E->getLocStart());
}
case Expr::DeclRefExprClass: {
  if (isa<EnumConstantDecl>(cast<DeclRefExpr>(E)->getDecl()))
    return NoDiag();
  const ValueDecl *D = cast<DeclRefExpr>(E)->getDecl();
  if (Ctx.getLangOpts().CPlusPlus &&
      D && IsConstNonVolatile(D->getType())) {
    // Parameter variables are never constants.  Without this check,
    // getAnyInitializer() can find a default argument, which leads
    // to chaos.
    if (isa<ParmVarDecl>(D))
      return ICEDiag(IK_NotICE, cast<DeclRefExpr>(E)->getLocation());

    // C++ 7.1.5.1p2
    //   A variable of non-volatile const-qualified integral or enumeration
    //   type initialized by an ICE can be used in ICEs.
    if (const VarDecl *Dcl = dyn_cast<VarDecl>(D)) {
      if (!Dcl->getType()->isIntegralOrEnumerationType())
        return ICEDiag(IK_NotICE, cast<DeclRefExpr>(E)->getLocation());

      const VarDecl *VD;
      // Look for a declaration of this variable that has an initializer, and
      // check whether it is an ICE.
      if (Dcl->getAnyInitializer(VD) && VD->checkInitIsICE())
        return NoDiag();
      else
        return ICEDiag(IK_NotICE, cast<DeclRefExpr>(E)->getLocation());
    }
  }
  return ICEDiag(IK_NotICE, E->getLocStart());
}
case Expr::UnaryOperatorClass: {
  const UnaryOperator *Exp = cast<UnaryOperator>(E);
  switch (Exp->getOpcode()) {
  case UO_PostInc:
  case UO_PostDec:
  case UO_PreInc:
  case UO_PreDec:
  case UO_AddrOf:
  case UO_Deref:
  case UO_Coawait:
    // C99 6.6/3 allows increment and decrement within unevaluated
    // subexpressions of constant expressions, but they can never be ICEs
    // because an ICE cannot contain an lvalue operand.
    return ICEDiag(IK_NotICE, E->getLocStart());
  case UO_Extension:
  case UO_LNot:
  case UO_Plus:
  case UO_Minus:
  case UO_Not:
  case UO_Real:
  case UO_Imag:
    return CheckICE(Exp->getSubExpr(), Ctx);
  }

  // OffsetOf falls through here.
  LLVM_FALLTHROUGH[[clang::fallthrough]];
}
case Expr::OffsetOfExprClass: {
  // Note that per C99, offsetof must be an ICE. And AFAIK, using
  // EvaluateAsRValue matches the proposed gcc behavior for cases like
  // "offsetof(struct s{int x[4];}, x[1.0])".  This doesn't affect
  // compliance: we should warn earlier for offsetof expressions with
  // array subscripts that aren't ICEs, and if the array subscripts
  // are ICEs, the value of the offsetof must be an integer constant.
  return CheckEvalInICE(E, Ctx);
}
case Expr::UnaryExprOrTypeTraitExprClass: {
  const UnaryExprOrTypeTraitExpr *Exp = cast<UnaryExprOrTypeTraitExpr>(E);
  if ((Exp->getKind() ==  UETT_SizeOf) &&
      Exp->getTypeOfArgument()->isVariableArrayType())
    return ICEDiag(IK_NotICE, E->getLocStart());
  return NoDiag();
}
case Expr::BinaryOperatorClass: {
  const BinaryOperator *Exp = cast<BinaryOperator>(E);
  switch (Exp->getOpcode()) {
  case BO_PtrMemD:
  case BO_PtrMemI:
  case BO_Assign:
  case BO_MulAssign:
  case BO_DivAssign:
  case BO_RemAssign:
  case BO_AddAssign:
  case BO_SubAssign:
  case BO_ShlAssign:
  case BO_ShrAssign:
  case BO_AndAssign:
  case BO_XorAssign:
  case BO_OrAssign:
  case BO_Cmp: // FIXME: Re-enable once we can evaluate this.
    // C99 6.6/3 allows assignments within unevaluated subexpressions of
    // constant expressions, but they can never be ICEs because an ICE cannot
    // contain an lvalue operand.
    return ICEDiag(IK_NotICE, E->getLocStart());

  case BO_Mul:
  case BO_Div:
  case BO_Rem:
  case BO_Add:
  case BO_Sub:
  case BO_Shl:
  case BO_Shr:
  case BO_LT:
  case BO_GT:
  case BO_LE:
  case BO_GE:
  case BO_EQ:
  case BO_NE:
  case BO_And:
  case BO_Xor:
  case BO_Or:
  case BO_Comma: {
    ICEDiag LHSResult = CheckICE(Exp->getLHS(), Ctx);
    ICEDiag RHSResult = CheckICE(Exp->getRHS(), Ctx);
    if (Exp->getOpcode() == BO_Div ||
        Exp->getOpcode() == BO_Rem) {
      // EvaluateAsRValue gives an error for undefined Div/Rem, so make sure
      // we don't evaluate one.
      if (LHSResult.Kind == IK_ICE && RHSResult.Kind == IK_ICE) {
        llvm::APSInt REval = Exp->getRHS()->EvaluateKnownConstInt(Ctx);
        if (REval == 0)
          return ICEDiag(IK_ICEIfUnevaluated, E->getLocStart());
        if (REval.isSigned() && REval.isAllOnesValue()) {
          llvm::APSInt LEval = Exp->getLHS()->EvaluateKnownConstInt(Ctx);
          if (LEval.isMinSignedValue())
            return ICEDiag(IK_ICEIfUnevaluated, E->getLocStart());
        }
      }
    }
    if (Exp->getOpcode() == BO_Comma) {
      if (Ctx.getLangOpts().C99) {
        // C99 6.6p3 introduces a strange edge case: comma can be in an ICE
        // if it isn't evaluated.
        if (LHSResult.Kind == IK_ICE && RHSResult.Kind == IK_ICE)
          return ICEDiag(IK_ICEIfUnevaluated, E->getLocStart());
      } else {
        // In both C89 and C++, commas in ICEs are illegal.
        return ICEDiag(IK_NotICE, E->getLocStart());
      }
    }
    return Worst(LHSResult, RHSResult);
  }
  case BO_LAnd:
  case BO_LOr: {
    ICEDiag LHSResult = CheckICE(Exp->getLHS(), Ctx);
    ICEDiag RHSResult = CheckICE(Exp->getRHS(), Ctx);
    if (LHSResult.Kind == IK_ICE && RHSResult.Kind == IK_ICEIfUnevaluated) {
      // Rare case where the RHS has a comma "side-effect"; we need
      // to actually check the condition to see whether the side
      // with the comma is evaluated.
      if ((Exp->getOpcode() == BO_LAnd) !=
          (Exp->getLHS()->EvaluateKnownConstInt(Ctx) == 0))
        return RHSResult;
      return NoDiag();
    }

    return Worst(LHSResult, RHSResult);
  }
  }
  LLVM_FALLTHROUGH[[clang::fallthrough]];
}
case Expr::ImplicitCastExprClass:
case Expr::CStyleCastExprClass:
case Expr::CXXFunctionalCastExprClass:
case Expr::CXXStaticCastExprClass:
case Expr::CXXReinterpretCastExprClass:
case Expr::CXXConstCastExprClass:
case Expr::ObjCBridgedCastExprClass: {
  const Expr *SubExpr = cast<CastExpr>(E)->getSubExpr();
  if (isa<ExplicitCastExpr>(E)) {
    if (const FloatingLiteral *FL
          = dyn_cast<FloatingLiteral>(SubExpr->IgnoreParenImpCasts())) {
      unsigned DestWidth = Ctx.getIntWidth(E->getType());
      bool DestSigned = E->getType()->isSignedIntegerOrEnumerationType();
      APSInt IgnoredVal(DestWidth, !DestSigned);
      bool Ignored;
      // If the value does not fit in the destination type, the behavior is
      // undefined, so we are not required to treat it as a constant
      // expression.
      if (FL->getValue().convertToInteger(IgnoredVal,
                                          llvm::APFloat::rmTowardZero,
                                          &Ignored) & APFloat::opInvalidOp)
        return ICEDiag(IK_NotICE, E->getLocStart());
      return NoDiag();
    }
  }
  switch (cast<CastExpr>(E)->getCastKind()) {
  case CK_LValueToRValue:
  case CK_AtomicToNonAtomic:
  case CK_NonAtomicToAtomic:
  case CK_NoOp:
  case CK_IntegralToBoolean:
  case CK_IntegralCast:
    return CheckICE(SubExpr, Ctx);
  default:
    return ICEDiag(IK_NotICE, E->getLocStart());
  }
}
case Expr::BinaryConditionalOperatorClass: {
  const BinaryConditionalOperator *Exp = cast<BinaryConditionalOperator>(E);
  ICEDiag CommonResult = CheckICE(Exp->getCommon(), Ctx);
  if (CommonResult.Kind == IK_NotICE) return CommonResult;
  ICEDiag FalseResult = CheckICE(Exp->getFalseExpr(), Ctx);
  if (FalseResult.Kind == IK_NotICE) return FalseResult;
  if (CommonResult.Kind == IK_ICEIfUnevaluated) return CommonResult;
  if (FalseResult.Kind == IK_ICEIfUnevaluated &&
      Exp->getCommon()->EvaluateKnownConstInt(Ctx) != 0) return NoDiag();
  return FalseResult;
}
case Expr::ConditionalOperatorClass: {
  const ConditionalOperator *Exp = cast<ConditionalOperator>(E);
  // If the condition (ignoring parens) is a __builtin_constant_p call,
  // then only the true side is actually considered in an integer constant
  // expression, and it is fully evaluated.  This is an important GNU
  // extension.  See GCC PR38377 for discussion.
  if (const CallExpr *CallCE
      = dyn_cast<CallExpr>(Exp->getCond()->IgnoreParenCasts()))
    if (CallCE->getBuiltinCallee() == Builtin::BI__builtin_constant_p)
      return CheckEvalInICE(E, Ctx);
  ICEDiag CondResult = CheckICE(Exp->getCond(), Ctx);
  if (CondResult.Kind == IK_NotICE)
    return CondResult;

  ICEDiag TrueResult = CheckICE(Exp->getTrueExpr(), Ctx);
  ICEDiag FalseResult = CheckICE(Exp->getFalseExpr(), Ctx);

  if (TrueResult.Kind == IK_NotICE)
    return TrueResult;
  if (FalseResult.Kind == IK_NotICE)
    return FalseResult;
  if (CondResult.Kind == IK_ICEIfUnevaluated)
    return CondResult;
  if (TrueResult.Kind == IK_ICE && FalseResult.Kind == IK_ICE)
    return NoDiag();
  // Rare case where the diagnostics depend on which side is evaluated
  // Note that if we get here, CondResult is 0, and at least one of
  // TrueResult and FalseResult is non-zero.
  if (Exp->getCond()->EvaluateKnownConstInt(Ctx) == 0)
    return FalseResult;
  return TrueResult;
}
case Expr::CXXDefaultArgExprClass:
  return CheckICE(cast<CXXDefaultArgExpr>(E)->getExpr(), Ctx);
case Expr::CXXDefaultInitExprClass:
  return CheckICE(cast<CXXDefaultInitExpr>(E)->getExpr(), Ctx);
case Expr::ChooseExprClass: {
  return CheckICE(cast<ChooseExpr>(E)->getChosenSubExpr(), Ctx);
}
}

llvm_unreachable("Invalid StmtClass!")::llvm::llvm_unreachable_internal("Invalid StmtClass!", "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 10683);
10684}

10686/// Evaluate an expression as a C++11 integral constant expression.
10687static bool EvaluateCPlusPlus11IntegralConstantExpr(const ASTContext &Ctx,
                                                  const Expr *E,
                                                  llvm::APSInt *Value,
                                                  SourceLocation *Loc) {
if (!E->getType()->isIntegralOrEnumerationType()) {
  if (Loc) *Loc = E->getExprLoc();
  return false;
}

APValue Result;
if (!E->isCXX11ConstantExpr(Ctx, &Result, Loc))
  return false;

if (!Result.isInt()) {
  if (Loc) *Loc = E->getExprLoc();
  return false;
}

if (Value) *Value = Result.getInt();
return true;
10707}

10709bool Expr::isIntegerConstantExpr(const ASTContext &Ctx,
                               SourceLocation *Loc) const {
if (Ctx.getLangOpts().CPlusPlus11)
  return EvaluateCPlusPlus11IntegralConstantExpr(Ctx, this, nullptr, Loc);

ICEDiag D = CheckICE(this, Ctx);
if (D.Kind != IK_ICE) {
  if (Loc) *Loc = D.Loc;
  return false;
}
return true;
10720}

10722bool Expr::isIntegerConstantExpr(llvm::APSInt &Value, const ASTContext &Ctx,
                               SourceLocation *Loc, bool isEvaluated) const {
if (Ctx.getLangOpts().CPlusPlus11)
  return EvaluateCPlusPlus11IntegralConstantExpr(Ctx, this, &Value, Loc);

if (!isIntegerConstantExpr(Ctx, Loc))
  return false;
// The only possible side-effects here are due to UB discovered in the
// evaluation (for instance, INT_MAX + 1). In such a case, we are still
// required to treat the expression as an ICE, so we produce the folded
// value.
if (!EvaluateAsInt(Value, Ctx, SE_AllowSideEffects))
  llvm_unreachable("ICE cannot be evaluated!")::llvm::llvm_unreachable_internal("ICE cannot be evaluated!",
 "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 10734);
return true;
10736}

10738bool Expr::isCXX98IntegralConstantExpr(const ASTContext &Ctx) const {
return CheckICE(this, Ctx).Kind == IK_ICE;
10740}

10742bool Expr::isCXX11ConstantExpr(const ASTContext &Ctx, APValue *Result,
                             SourceLocation *Loc) const {
// We support this checking in C++98 mode in order to diagnose compatibility
// issues.
assert(Ctx.getLangOpts().CPlusPlus)(static_cast <bool> (Ctx.getLangOpts().CPlusPlus) ? void
 (0) : __assert_fail ("Ctx.getLangOpts().CPlusPlus", "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 10746, __extension__ __PRETTY_FUNCTION__));

// Build evaluation settings.
Expr::EvalStatus Status;
SmallVector<PartialDiagnosticAt, 8> Diags;
Status.Diag = &Diags;
EvalInfo Info(Ctx, Status, EvalInfo::EM_ConstantExpression);

APValue Scratch;
bool IsConstExpr = ::EvaluateAsRValue(Info, this, Result ? *Result : Scratch);

if (!Diags.empty()) {
  IsConstExpr = false;
  if (Loc) *Loc = Diags[0].first;
} else if (!IsConstExpr) {
  // FIXME: This shouldn't happen.
  if (Loc) *Loc = getExprLoc();
}

return IsConstExpr;
10766}

10768bool Expr::EvaluateWithSubstitution(APValue &Value, ASTContext &Ctx,
                                  const FunctionDecl *Callee,
                                  ArrayRef<const Expr*> Args,
                                  const Expr *This) const {
Expr::EvalStatus Status;
EvalInfo Info(Ctx, Status, EvalInfo::EM_ConstantExpressionUnevaluated);

LValue ThisVal;
const LValue *ThisPtr = nullptr;
if (This) {
10778#ifndef NDEBUG
  auto *MD = dyn_cast<CXXMethodDecl>(Callee);
  assert(MD && "Don't provide `this` for non-methods.")(static_cast <bool> (MD && "Don't provide `this` for non-methods."
) ? void (0) : __assert_fail ("MD && \"Don't provide `this` for non-methods.\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 10780, __extension__ __PRETTY_FUNCTION__));
  assert(!MD->isStatic() && "Don't provide `this` for static methods.")(static_cast <bool> (!MD->isStatic() && "Don't provide `this` for static methods."
) ? void (0) : __assert_fail ("!MD->isStatic() && \"Don't provide `this` for static methods.\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 10781, __extension__ __PRETTY_FUNCTION__));
10782#endif
  if (EvaluateObjectArgument(Info, This, ThisVal))
    ThisPtr = &ThisVal;
  if (Info.EvalStatus.HasSideEffects)
    return false;
}

ArgVector ArgValues(Args.size());
for (ArrayRef<const Expr*>::iterator I = Args.begin(), E = Args.end();
     I != E; ++I) {
  if ((*I)->isValueDependent() ||
      !Evaluate(ArgValues[I - Args.begin()], Info, *I))
    // If evaluation fails, throw away the argument entirely.
    ArgValues[I - Args.begin()] = APValue();
  if (Info.EvalStatus.HasSideEffects)
    return false;
}

// Build fake call to Callee.
CallStackFrame Frame(Info, Callee->getLocation(), Callee, ThisPtr,
                     ArgValues.data());
return Evaluate(Value, Info, this) && !Info.EvalStatus.HasSideEffects;
10804}

10806bool Expr::isPotentialConstantExpr(const FunctionDecl *FD,
                                 SmallVectorImpl<
                                   PartialDiagnosticAt> &Diags) {
// FIXME: It would be useful to check constexpr function templates, but at the
// moment the constant expression evaluator cannot cope with the non-rigorous
// ASTs which we build for dependent expressions.
if (FD->isDependentContext())
  return true;

Expr::EvalStatus Status;
Status.Diag = &Diags;

EvalInfo Info(FD->getASTContext(), Status,
              EvalInfo::EM_PotentialConstantExpression);

const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD);
const CXXRecordDecl *RD = MD ? MD->getParent()->getCanonicalDecl() : nullptr;

// Fabricate an arbitrary expression on the stack and pretend that it
// is a temporary being used as the 'this' pointer.
LValue This;
ImplicitValueInitExpr VIE(RD ? Info.Ctx.getRecordType(RD) : Info.Ctx.IntTy);
This.set(&VIE, Info.CurrentCall->Index);

ArrayRef<const Expr*> Args;

APValue Scratch;
if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(FD)) {
  // Evaluate the call as a constant initializer, to allow the construction
  // of objects of non-literal types.
  Info.setEvaluatingDecl(This.getLValueBase(), Scratch);
  HandleConstructorCall(&VIE, This, Args, CD, Info, Scratch);
} else {
  SourceLocation Loc = FD->getLocation();
  HandleFunctionCall(Loc, FD, (MD && MD->isInstance()) ? &This : nullptr,
                     Args, FD->getBody(), Info, Scratch, nullptr);
}

return Diags.empty();
10845}

10847bool Expr::isPotentialConstantExprUnevaluated(Expr *E,
                                            const FunctionDecl *FD,
                                            SmallVectorImpl<
                                              PartialDiagnosticAt> &Diags) {
Expr::EvalStatus Status;
Status.Diag = &Diags;

EvalInfo Info(FD->getASTContext(), Status,
              EvalInfo::EM_PotentialConstantExpressionUnevaluated);

// Fabricate a call stack frame to give the arguments a plausible cover story.
ArrayRef<const Expr*> Args;
ArgVector ArgValues(0);
bool Success = EvaluateArgs(Args, ArgValues, Info);
(void)Success;
assert(Success &&(static_cast <bool> (Success && "Failed to set up arguments for potential constant evaluation"
) ? void (0) : __assert_fail ("Success && \"Failed to set up arguments for potential constant evaluation\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 10863, __extension__ __PRETTY_FUNCTION__))
       "Failed to set up arguments for potential constant evaluation")(static_cast <bool> (Success && "Failed to set up arguments for potential constant evaluation"
) ? void (0) : __assert_fail ("Success && \"Failed to set up arguments for potential constant evaluation\""
, "/build/llvm-toolchain-snapshot-7~svn326551/tools/clang/lib/AST/ExprConstant.cpp"
, 10863, __extension__ __PRETTY_FUNCTION__));
CallStackFrame Frame(Info, SourceLocation(), FD, nullptr, ArgValues.data());

APValue ResultScratch;
Evaluate(ResultScratch, Info, E);
return Diags.empty();
10869}

10871bool Expr::tryEvaluateObjectSize(uint64_t &Result, ASTContext &Ctx,
                               unsigned Type) const {
if (!getType()->isPointerType())
  return false;

Expr::EvalStatus Status;
EvalInfo Info(Ctx, Status, EvalInfo::EM_ConstantFold);
return tryEvaluateBuiltinObjectSize(this, Type, Info, Result);
10879}