LLVM  9.0.0svn
DebugLocEntry.h
Go to the documentation of this file.
1 //===-- llvm/CodeGen/DebugLocEntry.h - Entry in debug_loc list -*- C++ -*--===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #ifndef LLVM_LIB_CODEGEN_ASMPRINTER_DEBUGLOCENTRY_H
10 #define LLVM_LIB_CODEGEN_ASMPRINTER_DEBUGLOCENTRY_H
11 
12 #include "DebugLocStream.h"
13 #include "llvm/Config/llvm-config.h"
14 #include "llvm/IR/Constants.h"
15 #include "llvm/IR/DebugInfo.h"
16 #include "llvm/MC/MCSymbol.h"
18 #include "llvm/Support/Debug.h"
19 
20 namespace llvm {
21 class AsmPrinter;
22 
23 /// A single location or constant.
24 class DbgValueLoc {
25  /// Any complex address location expression for this DbgValueLoc.
26  const DIExpression *Expression;
27 
28  /// Type of entry that this represents.
29  enum EntryType { E_Location, E_Integer, E_ConstantFP, E_ConstantInt };
30  enum EntryType EntryKind;
31 
32  /// Either a constant,
33  union {
34  int64_t Int;
35  const ConstantFP *CFP;
36  const ConstantInt *CIP;
37  } Constant;
38 
39  /// Or a location in the machine frame.
40  MachineLocation Loc;
41 
42 public:
43  DbgValueLoc(const DIExpression *Expr, int64_t i)
44  : Expression(Expr), EntryKind(E_Integer) {
45  Constant.Int = i;
46  }
47  DbgValueLoc(const DIExpression *Expr, const ConstantFP *CFP)
48  : Expression(Expr), EntryKind(E_ConstantFP) {
49  Constant.CFP = CFP;
50  }
51  DbgValueLoc(const DIExpression *Expr, const ConstantInt *CIP)
52  : Expression(Expr), EntryKind(E_ConstantInt) {
53  Constant.CIP = CIP;
54  }
56  : Expression(Expr), EntryKind(E_Location), Loc(Loc) {
57  assert(cast<DIExpression>(Expr)->isValid());
58  }
59 
60  bool isLocation() const { return EntryKind == E_Location; }
61  bool isInt() const { return EntryKind == E_Integer; }
62  bool isConstantFP() const { return EntryKind == E_ConstantFP; }
63  bool isConstantInt() const { return EntryKind == E_ConstantInt; }
64  int64_t getInt() const { return Constant.Int; }
65  const ConstantFP *getConstantFP() const { return Constant.CFP; }
66  const ConstantInt *getConstantInt() const { return Constant.CIP; }
67  MachineLocation getLoc() const { return Loc; }
68  bool isFragment() const { return getExpression()->isFragment(); }
69  const DIExpression *getExpression() const { return Expression; }
70  friend bool operator==(const DbgValueLoc &, const DbgValueLoc &);
71  friend bool operator<(const DbgValueLoc &, const DbgValueLoc &);
72 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
73  LLVM_DUMP_METHOD void dump() const {
74  if (isLocation()) {
75  llvm::dbgs() << "Loc = { reg=" << Loc.getReg() << " ";
76  if (Loc.isIndirect())
77  llvm::dbgs() << "+0";
78  llvm::dbgs() << "} ";
79  } else if (isConstantInt())
80  Constant.CIP->dump();
81  else if (isConstantFP())
82  Constant.CFP->dump();
83  if (Expression)
84  Expression->dump();
85  }
86 #endif
87 };
88 
89 /// This struct describes location entries emitted in the .debug_loc
90 /// section.
92  /// Begin and end symbols for the address range that this location is valid.
93  const MCSymbol *Begin;
94  const MCSymbol *End;
95 
96  /// A nonempty list of locations/constants belonging to this entry,
97  /// sorted by offset.
99 
100 public:
101  /// Create a location list entry for the range [\p Begin, \p End).
102  ///
103  /// \param Vals One or more values describing (parts of) the variable.
104  DebugLocEntry(const MCSymbol *Begin, const MCSymbol *End,
106  : Begin(Begin), End(End) {
107  addValues(Vals);
108  }
109 
110  /// Attempt to merge this DebugLocEntry with Next and return
111  /// true if the merge was successful. Entries can be merged if they
112  /// share the same Loc/Constant and if Next immediately follows this
113  /// Entry.
114  bool MergeRanges(const DebugLocEntry &Next) {
115  // If this and Next are describing the same variable, merge them.
116  if ((End == Next.Begin && Values == Next.Values)) {
117  End = Next.End;
118  return true;
119  }
120  return false;
121  }
122 
123  const MCSymbol *getBeginSym() const { return Begin; }
124  const MCSymbol *getEndSym() const { return End; }
125  ArrayRef<DbgValueLoc> getValues() const { return Values; }
127  Values.append(Vals.begin(), Vals.end());
128  sortUniqueValues();
129  assert((Values.size() == 1 || all_of(Values, [](DbgValueLoc V) {
130  return V.isFragment();
131  })) && "must either have a single value or multiple pieces");
132  }
133 
134  // Sort the pieces by offset.
135  // Remove any duplicate entries by dropping all but the first.
137  llvm::sort(Values);
138  Values.erase(std::unique(Values.begin(), Values.end(),
139  [](const DbgValueLoc &A, const DbgValueLoc &B) {
140  return A.getExpression() == B.getExpression();
141  }),
142  Values.end());
143  }
144 
145  /// Lower this entry into a DWARF expression.
146  void finalize(const AsmPrinter &AP,
148  const DIBasicType *BT,
149  DwarfCompileUnit &TheCU);
150 };
151 
152 /// Compare two DbgValueLocs for equality.
153 inline bool operator==(const DbgValueLoc &A,
154  const DbgValueLoc &B) {
155  if (A.EntryKind != B.EntryKind)
156  return false;
157 
158  if (A.Expression != B.Expression)
159  return false;
160 
161  switch (A.EntryKind) {
162  case DbgValueLoc::E_Location:
163  return A.Loc == B.Loc;
164  case DbgValueLoc::E_Integer:
165  return A.Constant.Int == B.Constant.Int;
166  case DbgValueLoc::E_ConstantFP:
167  return A.Constant.CFP == B.Constant.CFP;
168  case DbgValueLoc::E_ConstantInt:
169  return A.Constant.CIP == B.Constant.CIP;
170  }
171  llvm_unreachable("unhandled EntryKind");
172 }
173 
174 /// Compare two fragments based on their offset.
175 inline bool operator<(const DbgValueLoc &A,
176  const DbgValueLoc &B) {
177  return A.getExpression()->getFragmentInfo()->OffsetInBits <
178  B.getExpression()->getFragmentInfo()->OffsetInBits;
179 }
180 
181 }
182 
183 #endif
const ConstantInt * CIP
Definition: DebugLocEntry.h:36
bool MergeRanges(const DebugLocEntry &Next)
Attempt to merge this DebugLocEntry with Next and return true if the merge was successful.
Builder for DebugLocStream lists.
int64_t getInt() const
Definition: DebugLocEntry.h:64
void addValues(ArrayRef< DbgValueLoc > Vals)
This struct describes location entries emitted in the .debug_loc section.
Definition: DebugLocEntry.h:91
This class represents lattice values for constants.
Definition: AllocatorList.h:23
#define LLVM_DUMP_METHOD
Mark debug helper function definitions like dump() that should not be stripped from debug builds...
Definition: Compiler.h:473
const ConstantFP * getConstantFP() const
Definition: DebugLocEntry.h:65
friend bool operator==(const DbgValueLoc &, const DbgValueLoc &)
Compare two DbgValueLocs for equality.
arc branch finalize
MCSymbol - Instances of this class represent a symbol name in the MC file, and MCSymbols are created ...
Definition: MCSymbol.h:41
iterator begin() const
Definition: ArrayRef.h:136
bool isInt() const
Definition: DebugLocEntry.h:61
bool isConstantFP() const
Definition: DebugLocEntry.h:62
unsigned getReg() const
DbgValueLoc(const DIExpression *Expr, int64_t i)
Definition: DebugLocEntry.h:43
DebugLocEntry(const MCSymbol *Begin, const MCSymbol *End, ArrayRef< DbgValueLoc > Vals)
Create a location list entry for the range [Begin, End).
bool all_of(R &&range, UnaryPredicate P)
Provide wrappers to std::all_of which take ranges instead of having to pass begin/end explicitly...
Definition: STLExtras.h:1192
const ConstantInt * getConstantInt() const
Definition: DebugLocEntry.h:66
bool isFragment() const
Definition: DebugLocEntry.h:68
void dump() const
Support for debugging, callable in GDB: V->dump()
Definition: AsmWriter.cpp:4382
const MCSymbol * getBeginSym() const
DbgValueLoc(const DIExpression *Expr, const ConstantFP *CFP)
Definition: DebugLocEntry.h:47
ArrayRef - Represent a constant reference to an array (0 or more elements consecutively in memory)...
Definition: APInt.h:32
static Optional< FragmentInfo > getFragmentInfo(expr_op_iterator Start, expr_op_iterator End)
Retrieve the details of this fragment expression.
DbgValueLoc(const DIExpression *Expr, const ConstantInt *CIP)
Definition: DebugLocEntry.h:51
const DIExpression * getExpression() const
Definition: DebugLocEntry.h:69
static GCRegistry::Add< OcamlGC > B("ocaml", "ocaml 3.10-compatible GC")
This is an important base class in LLVM.
Definition: Constant.h:41
This file contains the declarations for the subclasses of Constant, which represent the different fla...
ConstantFP - Floating Point Values [float, double].
Definition: Constants.h:263
const ConstantFP * CFP
Definition: DebugLocEntry.h:35
This class is intended to be used as a driving class for all asm writers.
Definition: AsmPrinter.h:78
LLVM_DUMP_METHOD void dump() const
Definition: DebugLocEntry.h:73
bool isLocation() const
Definition: DebugLocEntry.h:60
iterator erase(const_iterator CI)
Definition: SmallVector.h:434
size_t size() const
Definition: SmallVector.h:52
#define llvm_unreachable(msg)
Marks that the current location is not supposed to be reachable.
void sort(IteratorTy Start, IteratorTy End)
Definition: STLExtras.h:1122
ArrayRef< DbgValueLoc > getValues() const
This is the shared class of boolean and integer constants.
Definition: Constants.h:83
This is a &#39;vector&#39; (really, a variable-sized array), optimized for the case when the array is small...
Definition: SmallVector.h:837
friend bool operator<(const DbgValueLoc &, const DbgValueLoc &)
Compare two fragments based on their offset.
iterator end() const
Definition: ArrayRef.h:137
const MCSymbol * getEndSym() const
DWARF expression.
raw_ostream & dbgs()
dbgs() - This returns a reference to a raw_ostream for debugging messages.
Definition: Debug.cpp:132
void append(in_iter in_start, in_iter in_end)
Add the specified range to the end of the SmallVector.
Definition: SmallVector.h:387
const NodeList & List
Definition: RDFGraph.cpp:201
void dump() const
User-friendly dump.
Definition: AsmWriter.cpp:4404
MachineLocation getLoc() const
Definition: DebugLocEntry.h:67
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
bool isConstantInt() const
Definition: DebugLocEntry.h:63
bool isFragment() const
Return whether this is a piece of an aggregate variable.
DbgValueLoc(const DIExpression *Expr, MachineLocation Loc)
Definition: DebugLocEntry.h:55
A single location or constant.
Definition: DebugLocEntry.h:24
Basic type, like &#39;int&#39; or &#39;float&#39;.