Bug Summary

File:tools/clang/lib/Sema/SemaTemplateDeduction.cpp
Warning:line 756, column 3
Potential leak of memory pointed to by 'SawIndices.X'

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clang -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name SemaTemplateDeduction.cpp -analyzer-store=region -analyzer-opt-analyze-nested-blocks -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 -analyzer-config-compatibility-mode=true -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-9/lib/clang/9.0.0 -D CLANG_VENDOR="Debian " -D _DEBUG -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I /build/llvm-toolchain-snapshot-9~svn362543/build-llvm/tools/clang/lib/Sema -I /build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema -I /build/llvm-toolchain-snapshot-9~svn362543/tools/clang/include -I /build/llvm-toolchain-snapshot-9~svn362543/build-llvm/tools/clang/include -I /build/llvm-toolchain-snapshot-9~svn362543/build-llvm/include -I /build/llvm-toolchain-snapshot-9~svn362543/include -U NDEBUG -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/x86_64-linux-gnu/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/x86_64-linux-gnu/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0/backward -internal-isystem /usr/include/clang/9.0.0/include/ -internal-isystem /usr/local/include -internal-isystem /usr/lib/llvm-9/lib/clang/9.0.0/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-9~svn362543/build-llvm/tools/clang/lib/Sema -fdebug-prefix-map=/build/llvm-toolchain-snapshot-9~svn362543=. -ferror-limit 19 -fmessage-length 0 -fvisibility-inlines-hidden -stack-protector 2 -fobjc-runtime=gcc -fno-common -fdiagnostics-show-option -vectorize-loops -vectorize-slp -analyzer-output=html -analyzer-config stable-report-filename=true -o /tmp/scan-build-2019-06-05-060531-1271-1 -x c++ /build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp -faddrsig

/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp

1//===- SemaTemplateDeduction.cpp - Template Argument Deduction ------------===//
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// This file implements C++ template argument deduction.
10//
11//===----------------------------------------------------------------------===//
12
13#include "clang/Sema/TemplateDeduction.h"
14#include "TreeTransform.h"
15#include "TypeLocBuilder.h"
16#include "clang/AST/ASTContext.h"
17#include "clang/AST/ASTLambda.h"
18#include "clang/AST/Decl.h"
19#include "clang/AST/DeclAccessPair.h"
20#include "clang/AST/DeclBase.h"
21#include "clang/AST/DeclCXX.h"
22#include "clang/AST/DeclTemplate.h"
23#include "clang/AST/DeclarationName.h"
24#include "clang/AST/Expr.h"
25#include "clang/AST/ExprCXX.h"
26#include "clang/AST/NestedNameSpecifier.h"
27#include "clang/AST/TemplateBase.h"
28#include "clang/AST/TemplateName.h"
29#include "clang/AST/Type.h"
30#include "clang/AST/TypeLoc.h"
31#include "clang/AST/UnresolvedSet.h"
32#include "clang/Basic/AddressSpaces.h"
33#include "clang/Basic/ExceptionSpecificationType.h"
34#include "clang/Basic/LLVM.h"
35#include "clang/Basic/LangOptions.h"
36#include "clang/Basic/PartialDiagnostic.h"
37#include "clang/Basic/SourceLocation.h"
38#include "clang/Basic/Specifiers.h"
39#include "clang/Sema/Ownership.h"
40#include "clang/Sema/Sema.h"
41#include "clang/Sema/Template.h"
42#include "llvm/ADT/APInt.h"
43#include "llvm/ADT/APSInt.h"
44#include "llvm/ADT/ArrayRef.h"
45#include "llvm/ADT/DenseMap.h"
46#include "llvm/ADT/FoldingSet.h"
47#include "llvm/ADT/Optional.h"
48#include "llvm/ADT/SmallBitVector.h"
49#include "llvm/ADT/SmallPtrSet.h"
50#include "llvm/ADT/SmallVector.h"
51#include "llvm/Support/Casting.h"
52#include "llvm/Support/Compiler.h"
53#include "llvm/Support/ErrorHandling.h"
54#include <algorithm>
55#include <cassert>
56#include <tuple>
57#include <utility>
58
59namespace clang {
60
61 /// Various flags that control template argument deduction.
62 ///
63 /// These flags can be bitwise-OR'd together.
64 enum TemplateDeductionFlags {
65 /// No template argument deduction flags, which indicates the
66 /// strictest results for template argument deduction (as used for, e.g.,
67 /// matching class template partial specializations).
68 TDF_None = 0,
69
70 /// Within template argument deduction from a function call, we are
71 /// matching with a parameter type for which the original parameter was
72 /// a reference.
73 TDF_ParamWithReferenceType = 0x1,
74
75 /// Within template argument deduction from a function call, we
76 /// are matching in a case where we ignore cv-qualifiers.
77 TDF_IgnoreQualifiers = 0x02,
78
79 /// Within template argument deduction from a function call,
80 /// we are matching in a case where we can perform template argument
81 /// deduction from a template-id of a derived class of the argument type.
82 TDF_DerivedClass = 0x04,
83
84 /// Allow non-dependent types to differ, e.g., when performing
85 /// template argument deduction from a function call where conversions
86 /// may apply.
87 TDF_SkipNonDependent = 0x08,
88
89 /// Whether we are performing template argument deduction for
90 /// parameters and arguments in a top-level template argument
91 TDF_TopLevelParameterTypeList = 0x10,
92
93 /// Within template argument deduction from overload resolution per
94 /// C++ [over.over] allow matching function types that are compatible in
95 /// terms of noreturn and default calling convention adjustments, or
96 /// similarly matching a declared template specialization against a
97 /// possible template, per C++ [temp.deduct.decl]. In either case, permit
98 /// deduction where the parameter is a function type that can be converted
99 /// to the argument type.
100 TDF_AllowCompatibleFunctionType = 0x20,
101
102 /// Within template argument deduction for a conversion function, we are
103 /// matching with an argument type for which the original argument was
104 /// a reference.
105 TDF_ArgWithReferenceType = 0x40,
106 };
107}
108
109using namespace clang;
110using namespace sema;
111
112/// Compare two APSInts, extending and switching the sign as
113/// necessary to compare their values regardless of underlying type.
114static bool hasSameExtendedValue(llvm::APSInt X, llvm::APSInt Y) {
115 if (Y.getBitWidth() > X.getBitWidth())
116 X = X.extend(Y.getBitWidth());
117 else if (Y.getBitWidth() < X.getBitWidth())
118 Y = Y.extend(X.getBitWidth());
119
120 // If there is a signedness mismatch, correct it.
121 if (X.isSigned() != Y.isSigned()) {
122 // If the signed value is negative, then the values cannot be the same.
123 if ((Y.isSigned() && Y.isNegative()) || (X.isSigned() && X.isNegative()))
124 return false;
125
126 Y.setIsSigned(true);
127 X.setIsSigned(true);
128 }
129
130 return X == Y;
131}
132
133static Sema::TemplateDeductionResult
134DeduceTemplateArguments(Sema &S,
135 TemplateParameterList *TemplateParams,
136 const TemplateArgument &Param,
137 TemplateArgument Arg,
138 TemplateDeductionInfo &Info,
139 SmallVectorImpl<DeducedTemplateArgument> &Deduced);
140
141static Sema::TemplateDeductionResult
142DeduceTemplateArgumentsByTypeMatch(Sema &S,
143 TemplateParameterList *TemplateParams,
144 QualType Param,
145 QualType Arg,
146 TemplateDeductionInfo &Info,
147 SmallVectorImpl<DeducedTemplateArgument> &
148 Deduced,
149 unsigned TDF,
150 bool PartialOrdering = false,
151 bool DeducedFromArrayBound = false);
152
153static Sema::TemplateDeductionResult
154DeduceTemplateArguments(Sema &S, TemplateParameterList *TemplateParams,
155 ArrayRef<TemplateArgument> Params,
156 ArrayRef<TemplateArgument> Args,
157 TemplateDeductionInfo &Info,
158 SmallVectorImpl<DeducedTemplateArgument> &Deduced,
159 bool NumberOfArgumentsMustMatch);
160
161static void MarkUsedTemplateParameters(ASTContext &Ctx,
162 const TemplateArgument &TemplateArg,
163 bool OnlyDeduced, unsigned Depth,
164 llvm::SmallBitVector &Used);
165
166static void MarkUsedTemplateParameters(ASTContext &Ctx, QualType T,
167 bool OnlyDeduced, unsigned Level,
168 llvm::SmallBitVector &Deduced);
169
170/// If the given expression is of a form that permits the deduction
171/// of a non-type template parameter, return the declaration of that
172/// non-type template parameter.
173static NonTypeTemplateParmDecl *
174getDeducedParameterFromExpr(TemplateDeductionInfo &Info, Expr *E) {
175 // If we are within an alias template, the expression may have undergone
176 // any number of parameter substitutions already.
177 while (true) {
178 if (ImplicitCastExpr *IC = dyn_cast<ImplicitCastExpr>(E))
179 E = IC->getSubExpr();
180 else if (ConstantExpr *CE = dyn_cast<ConstantExpr>(E))
181 E = CE->getSubExpr();
182 else if (SubstNonTypeTemplateParmExpr *Subst =
183 dyn_cast<SubstNonTypeTemplateParmExpr>(E))
184 E = Subst->getReplacement();
185 else
186 break;
187 }
188
189 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E))
190 if (auto *NTTP = dyn_cast<NonTypeTemplateParmDecl>(DRE->getDecl()))
191 if (NTTP->getDepth() == Info.getDeducedDepth())
192 return NTTP;
193
194 return nullptr;
195}
196
197/// Determine whether two declaration pointers refer to the same
198/// declaration.
199static bool isSameDeclaration(Decl *X, Decl *Y) {
200 if (NamedDecl *NX = dyn_cast<NamedDecl>(X))
201 X = NX->getUnderlyingDecl();
202 if (NamedDecl *NY = dyn_cast<NamedDecl>(Y))
203 Y = NY->getUnderlyingDecl();
204
205 return X->getCanonicalDecl() == Y->getCanonicalDecl();
206}
207
208/// Verify that the given, deduced template arguments are compatible.
209///
210/// \returns The deduced template argument, or a NULL template argument if
211/// the deduced template arguments were incompatible.
212static DeducedTemplateArgument
213checkDeducedTemplateArguments(ASTContext &Context,
214 const DeducedTemplateArgument &X,
215 const DeducedTemplateArgument &Y) {
216 // We have no deduction for one or both of the arguments; they're compatible.
217 if (X.isNull())
218 return Y;
219 if (Y.isNull())
220 return X;
221
222 // If we have two non-type template argument values deduced for the same
223 // parameter, they must both match the type of the parameter, and thus must
224 // match each other's type. As we're only keeping one of them, we must check
225 // for that now. The exception is that if either was deduced from an array
226 // bound, the type is permitted to differ.
227 if (!X.wasDeducedFromArrayBound() && !Y.wasDeducedFromArrayBound()) {
228 QualType XType = X.getNonTypeTemplateArgumentType();
229 if (!XType.isNull()) {
230 QualType YType = Y.getNonTypeTemplateArgumentType();
231 if (YType.isNull() || !Context.hasSameType(XType, YType))
232 return DeducedTemplateArgument();
233 }
234 }
235
236 switch (X.getKind()) {
237 case TemplateArgument::Null:
238 llvm_unreachable("Non-deduced template arguments handled above")::llvm::llvm_unreachable_internal("Non-deduced template arguments handled above"
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 238)
;
239
240 case TemplateArgument::Type:
241 // If two template type arguments have the same type, they're compatible.
242 if (Y.getKind() == TemplateArgument::Type &&
243 Context.hasSameType(X.getAsType(), Y.getAsType()))
244 return X;
245
246 // If one of the two arguments was deduced from an array bound, the other
247 // supersedes it.
248 if (X.wasDeducedFromArrayBound() != Y.wasDeducedFromArrayBound())
249 return X.wasDeducedFromArrayBound() ? Y : X;
250
251 // The arguments are not compatible.
252 return DeducedTemplateArgument();
253
254 case TemplateArgument::Integral:
255 // If we deduced a constant in one case and either a dependent expression or
256 // declaration in another case, keep the integral constant.
257 // If both are integral constants with the same value, keep that value.
258 if (Y.getKind() == TemplateArgument::Expression ||
259 Y.getKind() == TemplateArgument::Declaration ||
260 (Y.getKind() == TemplateArgument::Integral &&
261 hasSameExtendedValue(X.getAsIntegral(), Y.getAsIntegral())))
262 return X.wasDeducedFromArrayBound() ? Y : X;
263
264 // All other combinations are incompatible.
265 return DeducedTemplateArgument();
266
267 case TemplateArgument::Template:
268 if (Y.getKind() == TemplateArgument::Template &&
269 Context.hasSameTemplateName(X.getAsTemplate(), Y.getAsTemplate()))
270 return X;
271
272 // All other combinations are incompatible.
273 return DeducedTemplateArgument();
274
275 case TemplateArgument::TemplateExpansion:
276 if (Y.getKind() == TemplateArgument::TemplateExpansion &&
277 Context.hasSameTemplateName(X.getAsTemplateOrTemplatePattern(),
278 Y.getAsTemplateOrTemplatePattern()))
279 return X;
280
281 // All other combinations are incompatible.
282 return DeducedTemplateArgument();
283
284 case TemplateArgument::Expression: {
285 if (Y.getKind() != TemplateArgument::Expression)
286 return checkDeducedTemplateArguments(Context, Y, X);
287
288 // Compare the expressions for equality
289 llvm::FoldingSetNodeID ID1, ID2;
290 X.getAsExpr()->Profile(ID1, Context, true);
291 Y.getAsExpr()->Profile(ID2, Context, true);
292 if (ID1 == ID2)
293 return X.wasDeducedFromArrayBound() ? Y : X;
294
295 // Differing dependent expressions are incompatible.
296 return DeducedTemplateArgument();
297 }
298
299 case TemplateArgument::Declaration:
300 assert(!X.wasDeducedFromArrayBound())((!X.wasDeducedFromArrayBound()) ? static_cast<void> (0
) : __assert_fail ("!X.wasDeducedFromArrayBound()", "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 300, __PRETTY_FUNCTION__))
;
301
302 // If we deduced a declaration and a dependent expression, keep the
303 // declaration.
304 if (Y.getKind() == TemplateArgument::Expression)
305 return X;
306
307 // If we deduced a declaration and an integral constant, keep the
308 // integral constant and whichever type did not come from an array
309 // bound.
310 if (Y.getKind() == TemplateArgument::Integral) {
311 if (Y.wasDeducedFromArrayBound())
312 return TemplateArgument(Context, Y.getAsIntegral(),
313 X.getParamTypeForDecl());
314 return Y;
315 }
316
317 // If we deduced two declarations, make sure that they refer to the
318 // same declaration.
319 if (Y.getKind() == TemplateArgument::Declaration &&
320 isSameDeclaration(X.getAsDecl(), Y.getAsDecl()))
321 return X;
322
323 // All other combinations are incompatible.
324 return DeducedTemplateArgument();
325
326 case TemplateArgument::NullPtr:
327 // If we deduced a null pointer and a dependent expression, keep the
328 // null pointer.
329 if (Y.getKind() == TemplateArgument::Expression)
330 return X;
331
332 // If we deduced a null pointer and an integral constant, keep the
333 // integral constant.
334 if (Y.getKind() == TemplateArgument::Integral)
335 return Y;
336
337 // If we deduced two null pointers, they are the same.
338 if (Y.getKind() == TemplateArgument::NullPtr)
339 return X;
340
341 // All other combinations are incompatible.
342 return DeducedTemplateArgument();
343
344 case TemplateArgument::Pack: {
345 if (Y.getKind() != TemplateArgument::Pack ||
346 X.pack_size() != Y.pack_size())
347 return DeducedTemplateArgument();
348
349 llvm::SmallVector<TemplateArgument, 8> NewPack;
350 for (TemplateArgument::pack_iterator XA = X.pack_begin(),
351 XAEnd = X.pack_end(),
352 YA = Y.pack_begin();
353 XA != XAEnd; ++XA, ++YA) {
354 TemplateArgument Merged = checkDeducedTemplateArguments(
355 Context, DeducedTemplateArgument(*XA, X.wasDeducedFromArrayBound()),
356 DeducedTemplateArgument(*YA, Y.wasDeducedFromArrayBound()));
357 if (Merged.isNull())
358 return DeducedTemplateArgument();
359 NewPack.push_back(Merged);
360 }
361
362 return DeducedTemplateArgument(
363 TemplateArgument::CreatePackCopy(Context, NewPack),
364 X.wasDeducedFromArrayBound() && Y.wasDeducedFromArrayBound());
365 }
366 }
367
368 llvm_unreachable("Invalid TemplateArgument Kind!")::llvm::llvm_unreachable_internal("Invalid TemplateArgument Kind!"
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 368)
;
369}
370
371/// Deduce the value of the given non-type template parameter
372/// as the given deduced template argument. All non-type template parameter
373/// deduction is funneled through here.
374static Sema::TemplateDeductionResult DeduceNonTypeTemplateArgument(
375 Sema &S, TemplateParameterList *TemplateParams,
376 NonTypeTemplateParmDecl *NTTP, const DeducedTemplateArgument &NewDeduced,
377 QualType ValueType, TemplateDeductionInfo &Info,
378 SmallVectorImpl<DeducedTemplateArgument> &Deduced) {
379 assert(NTTP->getDepth() == Info.getDeducedDepth() &&((NTTP->getDepth() == Info.getDeducedDepth() && "deducing non-type template argument with wrong depth"
) ? static_cast<void> (0) : __assert_fail ("NTTP->getDepth() == Info.getDeducedDepth() && \"deducing non-type template argument with wrong depth\""
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 380, __PRETTY_FUNCTION__))
380 "deducing non-type template argument with wrong depth")((NTTP->getDepth() == Info.getDeducedDepth() && "deducing non-type template argument with wrong depth"
) ? static_cast<void> (0) : __assert_fail ("NTTP->getDepth() == Info.getDeducedDepth() && \"deducing non-type template argument with wrong depth\""
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 380, __PRETTY_FUNCTION__))
;
381
382 DeducedTemplateArgument Result = checkDeducedTemplateArguments(
383 S.Context, Deduced[NTTP->getIndex()], NewDeduced);
384 if (Result.isNull()) {
385 Info.Param = NTTP;
386 Info.FirstArg = Deduced[NTTP->getIndex()];
387 Info.SecondArg = NewDeduced;
388 return Sema::TDK_Inconsistent;
389 }
390
391 Deduced[NTTP->getIndex()] = Result;
392 if (!S.getLangOpts().CPlusPlus17)
393 return Sema::TDK_Success;
394
395 if (NTTP->isExpandedParameterPack())
396 // FIXME: We may still need to deduce parts of the type here! But we
397 // don't have any way to find which slice of the type to use, and the
398 // type stored on the NTTP itself is nonsense. Perhaps the type of an
399 // expanded NTTP should be a pack expansion type?
400 return Sema::TDK_Success;
401
402 // Get the type of the parameter for deduction. If it's a (dependent) array
403 // or function type, we will not have decayed it yet, so do that now.
404 QualType ParamType = S.Context.getAdjustedParameterType(NTTP->getType());
405 if (auto *Expansion = dyn_cast<PackExpansionType>(ParamType))
406 ParamType = Expansion->getPattern();
407
408 // FIXME: It's not clear how deduction of a parameter of reference
409 // type from an argument (of non-reference type) should be performed.
410 // For now, we just remove reference types from both sides and let
411 // the final check for matching types sort out the mess.
412 return DeduceTemplateArgumentsByTypeMatch(
413 S, TemplateParams, ParamType.getNonReferenceType(),
414 ValueType.getNonReferenceType(), Info, Deduced, TDF_SkipNonDependent,
415 /*PartialOrdering=*/false,
416 /*ArrayBound=*/NewDeduced.wasDeducedFromArrayBound());
417}
418
419/// Deduce the value of the given non-type template parameter
420/// from the given integral constant.
421static Sema::TemplateDeductionResult DeduceNonTypeTemplateArgument(
422 Sema &S, TemplateParameterList *TemplateParams,
423 NonTypeTemplateParmDecl *NTTP, const llvm::APSInt &Value,
424 QualType ValueType, bool DeducedFromArrayBound, TemplateDeductionInfo &Info,
425 SmallVectorImpl<DeducedTemplateArgument> &Deduced) {
426 return DeduceNonTypeTemplateArgument(
427 S, TemplateParams, NTTP,
428 DeducedTemplateArgument(S.Context, Value, ValueType,
429 DeducedFromArrayBound),
430 ValueType, Info, Deduced);
431}
432
433/// Deduce the value of the given non-type template parameter
434/// from the given null pointer template argument type.
435static Sema::TemplateDeductionResult DeduceNullPtrTemplateArgument(
436 Sema &S, TemplateParameterList *TemplateParams,
437 NonTypeTemplateParmDecl *NTTP, QualType NullPtrType,
438 TemplateDeductionInfo &Info,
439 SmallVectorImpl<DeducedTemplateArgument> &Deduced) {
440 Expr *Value =
441 S.ImpCastExprToType(new (S.Context) CXXNullPtrLiteralExpr(
442 S.Context.NullPtrTy, NTTP->getLocation()),
443 NullPtrType, CK_NullToPointer)
444 .get();
445 return DeduceNonTypeTemplateArgument(S, TemplateParams, NTTP,
446 DeducedTemplateArgument(Value),
447 Value->getType(), Info, Deduced);
448}
449
450/// Deduce the value of the given non-type template parameter
451/// from the given type- or value-dependent expression.
452///
453/// \returns true if deduction succeeded, false otherwise.
454static Sema::TemplateDeductionResult DeduceNonTypeTemplateArgument(
455 Sema &S, TemplateParameterList *TemplateParams,
456 NonTypeTemplateParmDecl *NTTP, Expr *Value, TemplateDeductionInfo &Info,
457 SmallVectorImpl<DeducedTemplateArgument> &Deduced) {
458 return DeduceNonTypeTemplateArgument(S, TemplateParams, NTTP,
459 DeducedTemplateArgument(Value),
460 Value->getType(), Info, Deduced);
461}
462
463/// Deduce the value of the given non-type template parameter
464/// from the given declaration.
465///
466/// \returns true if deduction succeeded, false otherwise.
467static Sema::TemplateDeductionResult DeduceNonTypeTemplateArgument(
468 Sema &S, TemplateParameterList *TemplateParams,
469 NonTypeTemplateParmDecl *NTTP, ValueDecl *D, QualType T,
470 TemplateDeductionInfo &Info,
471 SmallVectorImpl<DeducedTemplateArgument> &Deduced) {
472 D = D ? cast<ValueDecl>(D->getCanonicalDecl()) : nullptr;
473 TemplateArgument New(D, T);
474 return DeduceNonTypeTemplateArgument(
475 S, TemplateParams, NTTP, DeducedTemplateArgument(New), T, Info, Deduced);
476}
477
478static Sema::TemplateDeductionResult
479DeduceTemplateArguments(Sema &S,
480 TemplateParameterList *TemplateParams,
481 TemplateName Param,
482 TemplateName Arg,
483 TemplateDeductionInfo &Info,
484 SmallVectorImpl<DeducedTemplateArgument> &Deduced) {
485 TemplateDecl *ParamDecl = Param.getAsTemplateDecl();
486 if (!ParamDecl) {
487 // The parameter type is dependent and is not a template template parameter,
488 // so there is nothing that we can deduce.
489 return Sema::TDK_Success;
490 }
491
492 if (TemplateTemplateParmDecl *TempParam
493 = dyn_cast<TemplateTemplateParmDecl>(ParamDecl)) {
494 // If we're not deducing at this depth, there's nothing to deduce.
495 if (TempParam->getDepth() != Info.getDeducedDepth())
496 return Sema::TDK_Success;
497
498 DeducedTemplateArgument NewDeduced(S.Context.getCanonicalTemplateName(Arg));
499 DeducedTemplateArgument Result = checkDeducedTemplateArguments(S.Context,
500 Deduced[TempParam->getIndex()],
501 NewDeduced);
502 if (Result.isNull()) {
503 Info.Param = TempParam;
504 Info.FirstArg = Deduced[TempParam->getIndex()];
505 Info.SecondArg = NewDeduced;
506 return Sema::TDK_Inconsistent;
507 }
508
509 Deduced[TempParam->getIndex()] = Result;
510 return Sema::TDK_Success;
511 }
512
513 // Verify that the two template names are equivalent.
514 if (S.Context.hasSameTemplateName(Param, Arg))
515 return Sema::TDK_Success;
516
517 // Mismatch of non-dependent template parameter to argument.
518 Info.FirstArg = TemplateArgument(Param);
519 Info.SecondArg = TemplateArgument(Arg);
520 return Sema::TDK_NonDeducedMismatch;
521}
522
523/// Deduce the template arguments by comparing the template parameter
524/// type (which is a template-id) with the template argument type.
525///
526/// \param S the Sema
527///
528/// \param TemplateParams the template parameters that we are deducing
529///
530/// \param Param the parameter type
531///
532/// \param Arg the argument type
533///
534/// \param Info information about the template argument deduction itself
535///
536/// \param Deduced the deduced template arguments
537///
538/// \returns the result of template argument deduction so far. Note that a
539/// "success" result means that template argument deduction has not yet failed,
540/// but it may still fail, later, for other reasons.
541static Sema::TemplateDeductionResult
542DeduceTemplateArguments(Sema &S,
543 TemplateParameterList *TemplateParams,
544 const TemplateSpecializationType *Param,
545 QualType Arg,
546 TemplateDeductionInfo &Info,
547 SmallVectorImpl<DeducedTemplateArgument> &Deduced) {
548 assert(Arg.isCanonical() && "Argument type must be canonical")((Arg.isCanonical() && "Argument type must be canonical"
) ? static_cast<void> (0) : __assert_fail ("Arg.isCanonical() && \"Argument type must be canonical\""
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 548, __PRETTY_FUNCTION__))
;
549
550 // Treat an injected-class-name as its underlying template-id.
551 if (auto *Injected = dyn_cast<InjectedClassNameType>(Arg))
552 Arg = Injected->getInjectedSpecializationType();
553
554 // Check whether the template argument is a dependent template-id.
555 if (const TemplateSpecializationType *SpecArg
556 = dyn_cast<TemplateSpecializationType>(Arg)) {
557 // Perform template argument deduction for the template name.
558 if (Sema::TemplateDeductionResult Result
559 = DeduceTemplateArguments(S, TemplateParams,
560 Param->getTemplateName(),
561 SpecArg->getTemplateName(),
562 Info, Deduced))
563 return Result;
564
565
566 // Perform template argument deduction on each template
567 // argument. Ignore any missing/extra arguments, since they could be
568 // filled in by default arguments.
569 return DeduceTemplateArguments(S, TemplateParams,
570 Param->template_arguments(),
571 SpecArg->template_arguments(), Info, Deduced,
572 /*NumberOfArgumentsMustMatch=*/false);
573 }
574
575 // If the argument type is a class template specialization, we
576 // perform template argument deduction using its template
577 // arguments.
578 const RecordType *RecordArg = dyn_cast<RecordType>(Arg);
579 if (!RecordArg) {
580 Info.FirstArg = TemplateArgument(QualType(Param, 0));
581 Info.SecondArg = TemplateArgument(Arg);
582 return Sema::TDK_NonDeducedMismatch;
583 }
584
585 ClassTemplateSpecializationDecl *SpecArg
586 = dyn_cast<ClassTemplateSpecializationDecl>(RecordArg->getDecl());
587 if (!SpecArg) {
588 Info.FirstArg = TemplateArgument(QualType(Param, 0));
589 Info.SecondArg = TemplateArgument(Arg);
590 return Sema::TDK_NonDeducedMismatch;
591 }
592
593 // Perform template argument deduction for the template name.
594 if (Sema::TemplateDeductionResult Result
595 = DeduceTemplateArguments(S,
596 TemplateParams,
597 Param->getTemplateName(),
598 TemplateName(SpecArg->getSpecializedTemplate()),
599 Info, Deduced))
600 return Result;
601
602 // Perform template argument deduction for the template arguments.
603 return DeduceTemplateArguments(S, TemplateParams, Param->template_arguments(),
604 SpecArg->getTemplateArgs().asArray(), Info,
605 Deduced, /*NumberOfArgumentsMustMatch=*/true);
606}
607
608/// Determines whether the given type is an opaque type that
609/// might be more qualified when instantiated.
610static bool IsPossiblyOpaquelyQualifiedType(QualType T) {
611 switch (T->getTypeClass()) {
612 case Type::TypeOfExpr:
613 case Type::TypeOf:
614 case Type::DependentName:
615 case Type::Decltype:
616 case Type::UnresolvedUsing:
617 case Type::TemplateTypeParm:
618 return true;
619
620 case Type::ConstantArray:
621 case Type::IncompleteArray:
622 case Type::VariableArray:
623 case Type::DependentSizedArray:
624 return IsPossiblyOpaquelyQualifiedType(
625 cast<ArrayType>(T)->getElementType());
626
627 default:
628 return false;
629 }
630}
631
632/// Helper function to build a TemplateParameter when we don't
633/// know its type statically.
634static TemplateParameter makeTemplateParameter(Decl *D) {
635 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(D))
636 return TemplateParameter(TTP);
637 if (NonTypeTemplateParmDecl *NTTP = dyn_cast<NonTypeTemplateParmDecl>(D))
638 return TemplateParameter(NTTP);
639
640 return TemplateParameter(cast<TemplateTemplateParmDecl>(D));
641}
642
643/// If \p Param is an expanded parameter pack, get the number of expansions.
644static Optional<unsigned> getExpandedPackSize(NamedDecl *Param) {
645 if (auto *NTTP = dyn_cast<NonTypeTemplateParmDecl>(Param))
646 if (NTTP->isExpandedParameterPack())
647 return NTTP->getNumExpansionTypes();
648
649 if (auto *TTP = dyn_cast<TemplateTemplateParmDecl>(Param))
650 if (TTP->isExpandedParameterPack())
651 return TTP->getNumExpansionTemplateParameters();
652
653 return None;
654}
655
656/// A pack that we're currently deducing.
657struct clang::DeducedPack {
658 // The index of the pack.
659 unsigned Index;
660
661 // The old value of the pack before we started deducing it.
662 DeducedTemplateArgument Saved;
663
664 // A deferred value of this pack from an inner deduction, that couldn't be
665 // deduced because this deduction hadn't happened yet.
666 DeducedTemplateArgument DeferredDeduction;
667
668 // The new value of the pack.
669 SmallVector<DeducedTemplateArgument, 4> New;
670
671 // The outer deduction for this pack, if any.
672 DeducedPack *Outer = nullptr;
673
674 DeducedPack(unsigned Index) : Index(Index) {}
675};
676
677namespace {
678
679/// A scope in which we're performing pack deduction.
680class PackDeductionScope {
681public:
682 /// Prepare to deduce the packs named within Pattern.
683 PackDeductionScope(Sema &S, TemplateParameterList *TemplateParams,
684 SmallVectorImpl<DeducedTemplateArgument> &Deduced,
685 TemplateDeductionInfo &Info, TemplateArgument Pattern)
686 : S(S), TemplateParams(TemplateParams), Deduced(Deduced), Info(Info) {
687 unsigned NumNamedPacks = addPacks(Pattern);
14
Calling 'PackDeductionScope::addPacks'
688 finishConstruction(NumNamedPacks);
689 }
690
691 /// Prepare to directly deduce arguments of the parameter with index \p Index.
692 PackDeductionScope(Sema &S, TemplateParameterList *TemplateParams,
693 SmallVectorImpl<DeducedTemplateArgument> &Deduced,
694 TemplateDeductionInfo &Info, unsigned Index)
695 : S(S), TemplateParams(TemplateParams), Deduced(Deduced), Info(Info) {
696 addPack(Index);
697 finishConstruction(1);
698 }
699
700private:
701 void addPack(unsigned Index) {
702 // Save the deduced template argument for the parameter pack expanded
703 // by this pack expansion, then clear out the deduction.
704 DeducedPack Pack(Index);
705 Pack.Saved = Deduced[Index];
706 Deduced[Index] = TemplateArgument();
707
708 // FIXME: What if we encounter multiple packs with different numbers of
709 // pre-expanded expansions? (This should already have been diagnosed
710 // during substitution.)
711 if (Optional<unsigned> ExpandedPackExpansions =
712 getExpandedPackSize(TemplateParams->getParam(Index)))
713 FixedNumExpansions = ExpandedPackExpansions;
714
715 Packs.push_back(Pack);
716 }
717
718 unsigned addPacks(TemplateArgument Pattern) {
719 // Compute the set of template parameter indices that correspond to
720 // parameter packs expanded by the pack expansion.
721 llvm::SmallBitVector SawIndices(TemplateParams->size());
15
Calling constructor for 'SmallBitVector'
19
Returning from constructor for 'SmallBitVector'
722
723 auto AddPack = [&](unsigned Index) {
724 if (SawIndices[Index])
725 return;
726 SawIndices[Index] = true;
727 addPack(Index);
728 };
729
730 // First look for unexpanded packs in the pattern.
731 SmallVector<UnexpandedParameterPack, 2> Unexpanded;
732 S.collectUnexpandedParameterPacks(Pattern, Unexpanded);
733 for (unsigned I = 0, N = Unexpanded.size(); I != N; ++I) {
20
Assuming 'I' is equal to 'N'
21
Loop condition is false. Execution continues on line 739
734 unsigned Depth, Index;
735 std::tie(Depth, Index) = getDepthAndIndex(Unexpanded[I]);
736 if (Depth == Info.getDeducedDepth())
737 AddPack(Index);
738 }
739 assert(!Packs.empty() && "Pack expansion without unexpanded packs?")((!Packs.empty() && "Pack expansion without unexpanded packs?"
) ? static_cast<void> (0) : __assert_fail ("!Packs.empty() && \"Pack expansion without unexpanded packs?\""
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 739, __PRETTY_FUNCTION__))
;
22
'?' condition is true
740
741 unsigned NumNamedPacks = Packs.size();
742
743 // We can also have deduced template parameters that do not actually
744 // appear in the pattern, but can be deduced by it (the type of a non-type
745 // template parameter pack, in particular). These won't have prevented us
746 // from partially expanding the pack.
747 llvm::SmallBitVector Used(TemplateParams->size());
748 MarkUsedTemplateParameters(S.Context, Pattern, /*OnlyDeduced*/true,
749 Info.getDeducedDepth(), Used);
750 for (int Index = Used.find_first(); Index != -1;
23
Assuming the condition is false
24
Loop condition is false. Execution continues on line 755
751 Index = Used.find_next(Index))
752 if (TemplateParams->getParam(Index)->isParameterPack())
753 AddPack(Index);
754
755 return NumNamedPacks;
756 }
25
Potential leak of memory pointed to by 'SawIndices.X'
757
758 void finishConstruction(unsigned NumNamedPacks) {
759 // Dig out the partially-substituted pack, if there is one.
760 const TemplateArgument *PartialPackArgs = nullptr;
761 unsigned NumPartialPackArgs = 0;
762 std::pair<unsigned, unsigned> PartialPackDepthIndex(-1u, -1u);
763 if (auto *Scope = S.CurrentInstantiationScope)
764 if (auto *Partial = Scope->getPartiallySubstitutedPack(
765 &PartialPackArgs, &NumPartialPackArgs))
766 PartialPackDepthIndex = getDepthAndIndex(Partial);
767
768 // This pack expansion will have been partially or fully expanded if
769 // it only names explicitly-specified parameter packs (including the
770 // partially-substituted one, if any).
771 bool IsExpanded = true;
772 for (unsigned I = 0; I != NumNamedPacks; ++I) {
773 if (Packs[I].Index >= Info.getNumExplicitArgs()) {
774 IsExpanded = false;
775 IsPartiallyExpanded = false;
776 break;
777 }
778 if (PartialPackDepthIndex ==
779 std::make_pair(Info.getDeducedDepth(), Packs[I].Index)) {
780 IsPartiallyExpanded = true;
781 }
782 }
783
784 // Skip over the pack elements that were expanded into separate arguments.
785 // If we partially expanded, this is the number of partial arguments.
786 if (IsPartiallyExpanded)
787 PackElements += NumPartialPackArgs;
788 else if (IsExpanded)
789 PackElements += *FixedNumExpansions;
790
791 for (auto &Pack : Packs) {
792 if (Info.PendingDeducedPacks.size() > Pack.Index)
793 Pack.Outer = Info.PendingDeducedPacks[Pack.Index];
794 else
795 Info.PendingDeducedPacks.resize(Pack.Index + 1);
796 Info.PendingDeducedPacks[Pack.Index] = &Pack;
797
798 if (PartialPackDepthIndex ==
799 std::make_pair(Info.getDeducedDepth(), Pack.Index)) {
800 Pack.New.append(PartialPackArgs, PartialPackArgs + NumPartialPackArgs);
801 // We pre-populate the deduced value of the partially-substituted
802 // pack with the specified value. This is not entirely correct: the
803 // value is supposed to have been substituted, not deduced, but the
804 // cases where this is observable require an exact type match anyway.
805 //
806 // FIXME: If we could represent a "depth i, index j, pack elem k"
807 // parameter, we could substitute the partially-substituted pack
808 // everywhere and avoid this.
809 if (!IsPartiallyExpanded)
810 Deduced[Pack.Index] = Pack.New[PackElements];
811 }
812 }
813 }
814
815public:
816 ~PackDeductionScope() {
817 for (auto &Pack : Packs)
818 Info.PendingDeducedPacks[Pack.Index] = Pack.Outer;
819 }
820
821 /// Determine whether this pack has already been partially expanded into a
822 /// sequence of (prior) function parameters / template arguments.
823 bool isPartiallyExpanded() { return IsPartiallyExpanded; }
824
825 /// Determine whether this pack expansion scope has a known, fixed arity.
826 /// This happens if it involves a pack from an outer template that has
827 /// (notionally) already been expanded.
828 bool hasFixedArity() { return FixedNumExpansions.hasValue(); }
829
830 /// Determine whether the next element of the argument is still part of this
831 /// pack. This is the case unless the pack is already expanded to a fixed
832 /// length.
833 bool hasNextElement() {
834 return !FixedNumExpansions || *FixedNumExpansions > PackElements;
835 }
836
837 /// Move to deducing the next element in each pack that is being deduced.
838 void nextPackElement() {
839 // Capture the deduced template arguments for each parameter pack expanded
840 // by this pack expansion, add them to the list of arguments we've deduced
841 // for that pack, then clear out the deduced argument.
842 for (auto &Pack : Packs) {
843 DeducedTemplateArgument &DeducedArg = Deduced[Pack.Index];
844 if (!Pack.New.empty() || !DeducedArg.isNull()) {
845 while (Pack.New.size() < PackElements)
846 Pack.New.push_back(DeducedTemplateArgument());
847 if (Pack.New.size() == PackElements)
848 Pack.New.push_back(DeducedArg);
849 else
850 Pack.New[PackElements] = DeducedArg;
851 DeducedArg = Pack.New.size() > PackElements + 1
852 ? Pack.New[PackElements + 1]
853 : DeducedTemplateArgument();
854 }
855 }
856 ++PackElements;
857 }
858
859 /// Finish template argument deduction for a set of argument packs,
860 /// producing the argument packs and checking for consistency with prior
861 /// deductions.
862 Sema::TemplateDeductionResult
863 finish(bool TreatNoDeductionsAsNonDeduced = true) {
864 // Build argument packs for each of the parameter packs expanded by this
865 // pack expansion.
866 for (auto &Pack : Packs) {
867 // Put back the old value for this pack.
868 Deduced[Pack.Index] = Pack.Saved;
869
870 // If we are deducing the size of this pack even if we didn't deduce any
871 // values for it, then make sure we build a pack of the right size.
872 // FIXME: Should we always deduce the size, even if the pack appears in
873 // a non-deduced context?
874 if (!TreatNoDeductionsAsNonDeduced)
875 Pack.New.resize(PackElements);
876
877 // Build or find a new value for this pack.
878 DeducedTemplateArgument NewPack;
879 if (PackElements && Pack.New.empty()) {
880 if (Pack.DeferredDeduction.isNull()) {
881 // We were not able to deduce anything for this parameter pack
882 // (because it only appeared in non-deduced contexts), so just
883 // restore the saved argument pack.
884 continue;
885 }
886
887 NewPack = Pack.DeferredDeduction;
888 Pack.DeferredDeduction = TemplateArgument();
889 } else if (Pack.New.empty()) {
890 // If we deduced an empty argument pack, create it now.
891 NewPack = DeducedTemplateArgument(TemplateArgument::getEmptyPack());
892 } else {
893 TemplateArgument *ArgumentPack =
894 new (S.Context) TemplateArgument[Pack.New.size()];
895 std::copy(Pack.New.begin(), Pack.New.end(), ArgumentPack);
896 NewPack = DeducedTemplateArgument(
897 TemplateArgument(llvm::makeArrayRef(ArgumentPack, Pack.New.size())),
898 // FIXME: This is wrong, it's possible that some pack elements are
899 // deduced from an array bound and others are not:
900 // template<typename ...T, T ...V> void g(const T (&...p)[V]);
901 // g({1, 2, 3}, {{}, {}});
902 // ... should deduce T = {int, size_t (from array bound)}.
903 Pack.New[0].wasDeducedFromArrayBound());
904 }
905
906 // Pick where we're going to put the merged pack.
907 DeducedTemplateArgument *Loc;
908 if (Pack.Outer) {
909 if (Pack.Outer->DeferredDeduction.isNull()) {
910 // Defer checking this pack until we have a complete pack to compare
911 // it against.
912 Pack.Outer->DeferredDeduction = NewPack;
913 continue;
914 }
915 Loc = &Pack.Outer->DeferredDeduction;
916 } else {
917 Loc = &Deduced[Pack.Index];
918 }
919
920 // Check the new pack matches any previous value.
921 DeducedTemplateArgument OldPack = *Loc;
922 DeducedTemplateArgument Result =
923 checkDeducedTemplateArguments(S.Context, OldPack, NewPack);
924
925 // If we deferred a deduction of this pack, check that one now too.
926 if (!Result.isNull() && !Pack.DeferredDeduction.isNull()) {
927 OldPack = Result;
928 NewPack = Pack.DeferredDeduction;
929 Result = checkDeducedTemplateArguments(S.Context, OldPack, NewPack);
930 }
931
932 NamedDecl *Param = TemplateParams->getParam(Pack.Index);
933 if (Result.isNull()) {
934 Info.Param = makeTemplateParameter(Param);
935 Info.FirstArg = OldPack;
936 Info.SecondArg = NewPack;
937 return Sema::TDK_Inconsistent;
938 }
939
940 // If we have a pre-expanded pack and we didn't deduce enough elements
941 // for it, fail deduction.
942 if (Optional<unsigned> Expansions = getExpandedPackSize(Param)) {
943 if (*Expansions != PackElements) {
944 Info.Param = makeTemplateParameter(Param);
945 Info.FirstArg = Result;
946 return Sema::TDK_IncompletePack;
947 }
948 }
949
950 *Loc = Result;
951 }
952
953 return Sema::TDK_Success;
954 }
955
956private:
957 Sema &S;
958 TemplateParameterList *TemplateParams;
959 SmallVectorImpl<DeducedTemplateArgument> &Deduced;
960 TemplateDeductionInfo &Info;
961 unsigned PackElements = 0;
962 bool IsPartiallyExpanded = false;
963 /// The number of expansions, if we have a fully-expanded pack in this scope.
964 Optional<unsigned> FixedNumExpansions;
965
966 SmallVector<DeducedPack, 2> Packs;
967};
968
969} // namespace
970
971/// Deduce the template arguments by comparing the list of parameter
972/// types to the list of argument types, as in the parameter-type-lists of
973/// function types (C++ [temp.deduct.type]p10).
974///
975/// \param S The semantic analysis object within which we are deducing
976///
977/// \param TemplateParams The template parameters that we are deducing
978///
979/// \param Params The list of parameter types
980///
981/// \param NumParams The number of types in \c Params
982///
983/// \param Args The list of argument types
984///
985/// \param NumArgs The number of types in \c Args
986///
987/// \param Info information about the template argument deduction itself
988///
989/// \param Deduced the deduced template arguments
990///
991/// \param TDF bitwise OR of the TemplateDeductionFlags bits that describe
992/// how template argument deduction is performed.
993///
994/// \param PartialOrdering If true, we are performing template argument
995/// deduction for during partial ordering for a call
996/// (C++0x [temp.deduct.partial]).
997///
998/// \returns the result of template argument deduction so far. Note that a
999/// "success" result means that template argument deduction has not yet failed,
1000/// but it may still fail, later, for other reasons.
1001static Sema::TemplateDeductionResult
1002DeduceTemplateArguments(Sema &S,
1003 TemplateParameterList *TemplateParams,
1004 const QualType *Params, unsigned NumParams,
1005 const QualType *Args, unsigned NumArgs,
1006 TemplateDeductionInfo &Info,
1007 SmallVectorImpl<DeducedTemplateArgument> &Deduced,
1008 unsigned TDF,
1009 bool PartialOrdering = false) {
1010 // C++0x [temp.deduct.type]p10:
1011 // Similarly, if P has a form that contains (T), then each parameter type
1012 // Pi of the respective parameter-type- list of P is compared with the
1013 // corresponding parameter type Ai of the corresponding parameter-type-list
1014 // of A. [...]
1015 unsigned ArgIdx = 0, ParamIdx = 0;
1016 for (; ParamIdx != NumParams; ++ParamIdx) {
1017 // Check argument types.
1018 const PackExpansionType *Expansion
1019 = dyn_cast<PackExpansionType>(Params[ParamIdx]);
1020 if (!Expansion) {
1021 // Simple case: compare the parameter and argument types at this point.
1022
1023 // Make sure we have an argument.
1024 if (ArgIdx >= NumArgs)
1025 return Sema::TDK_MiscellaneousDeductionFailure;
1026
1027 if (isa<PackExpansionType>(Args[ArgIdx])) {
1028 // C++0x [temp.deduct.type]p22:
1029 // If the original function parameter associated with A is a function
1030 // parameter pack and the function parameter associated with P is not
1031 // a function parameter pack, then template argument deduction fails.
1032 return Sema::TDK_MiscellaneousDeductionFailure;
1033 }
1034
1035 if (Sema::TemplateDeductionResult Result
1036 = DeduceTemplateArgumentsByTypeMatch(S, TemplateParams,
1037 Params[ParamIdx], Args[ArgIdx],
1038 Info, Deduced, TDF,
1039 PartialOrdering))
1040 return Result;
1041
1042 ++ArgIdx;
1043 continue;
1044 }
1045
1046 // C++0x [temp.deduct.type]p10:
1047 // If the parameter-declaration corresponding to Pi is a function
1048 // parameter pack, then the type of its declarator- id is compared with
1049 // each remaining parameter type in the parameter-type-list of A. Each
1050 // comparison deduces template arguments for subsequent positions in the
1051 // template parameter packs expanded by the function parameter pack.
1052
1053 QualType Pattern = Expansion->getPattern();
1054 PackDeductionScope PackScope(S, TemplateParams, Deduced, Info, Pattern);
1055
1056 // A pack scope with fixed arity is not really a pack any more, so is not
1057 // a non-deduced context.
1058 if (ParamIdx + 1 == NumParams || PackScope.hasFixedArity()) {
1059 for (; ArgIdx < NumArgs && PackScope.hasNextElement(); ++ArgIdx) {
1060 // Deduce template arguments from the pattern.
1061 if (Sema::TemplateDeductionResult Result
1062 = DeduceTemplateArgumentsByTypeMatch(S, TemplateParams, Pattern,
1063 Args[ArgIdx], Info, Deduced,
1064 TDF, PartialOrdering))
1065 return Result;
1066
1067 PackScope.nextPackElement();
1068 }
1069 } else {
1070 // C++0x [temp.deduct.type]p5:
1071 // The non-deduced contexts are:
1072 // - A function parameter pack that does not occur at the end of the
1073 // parameter-declaration-clause.
1074 //
1075 // FIXME: There is no wording to say what we should do in this case. We
1076 // choose to resolve this by applying the same rule that is applied for a
1077 // function call: that is, deduce all contained packs to their
1078 // explicitly-specified values (or to <> if there is no such value).
1079 //
1080 // This is seemingly-arbitrarily different from the case of a template-id
1081 // with a non-trailing pack-expansion in its arguments, which renders the
1082 // entire template-argument-list a non-deduced context.
1083
1084 // If the parameter type contains an explicitly-specified pack that we
1085 // could not expand, skip the number of parameters notionally created
1086 // by the expansion.
1087 Optional<unsigned> NumExpansions = Expansion->getNumExpansions();
1088 if (NumExpansions && !PackScope.isPartiallyExpanded()) {
1089 for (unsigned I = 0; I != *NumExpansions && ArgIdx < NumArgs;
1090 ++I, ++ArgIdx)
1091 PackScope.nextPackElement();
1092 }
1093 }
1094
1095 // Build argument packs for each of the parameter packs expanded by this
1096 // pack expansion.
1097 if (auto Result = PackScope.finish())
1098 return Result;
1099 }
1100
1101 // Make sure we don't have any extra arguments.
1102 if (ArgIdx < NumArgs)
1103 return Sema::TDK_MiscellaneousDeductionFailure;
1104
1105 return Sema::TDK_Success;
1106}
1107
1108/// Determine whether the parameter has qualifiers that the argument
1109/// lacks. Put another way, determine whether there is no way to add
1110/// a deduced set of qualifiers to the ParamType that would result in
1111/// its qualifiers matching those of the ArgType.
1112static bool hasInconsistentOrSupersetQualifiersOf(QualType ParamType,
1113 QualType ArgType) {
1114 Qualifiers ParamQs = ParamType.getQualifiers();
1115 Qualifiers ArgQs = ArgType.getQualifiers();
1116
1117 if (ParamQs == ArgQs)
1118 return false;
1119
1120 // Mismatched (but not missing) Objective-C GC attributes.
1121 if (ParamQs.getObjCGCAttr() != ArgQs.getObjCGCAttr() &&
1122 ParamQs.hasObjCGCAttr())
1123 return true;
1124
1125 // Mismatched (but not missing) address spaces.
1126 if (ParamQs.getAddressSpace() != ArgQs.getAddressSpace() &&
1127 ParamQs.hasAddressSpace())
1128 return true;
1129
1130 // Mismatched (but not missing) Objective-C lifetime qualifiers.
1131 if (ParamQs.getObjCLifetime() != ArgQs.getObjCLifetime() &&
1132 ParamQs.hasObjCLifetime())
1133 return true;
1134
1135 // CVR qualifiers inconsistent or a superset.
1136 return (ParamQs.getCVRQualifiers() & ~ArgQs.getCVRQualifiers()) != 0;
1137}
1138
1139/// Compare types for equality with respect to possibly compatible
1140/// function types (noreturn adjustment, implicit calling conventions). If any
1141/// of parameter and argument is not a function, just perform type comparison.
1142///
1143/// \param Param the template parameter type.
1144///
1145/// \param Arg the argument type.
1146bool Sema::isSameOrCompatibleFunctionType(CanQualType Param,
1147 CanQualType Arg) {
1148 const FunctionType *ParamFunction = Param->getAs<FunctionType>(),
1149 *ArgFunction = Arg->getAs<FunctionType>();
1150
1151 // Just compare if not functions.
1152 if (!ParamFunction || !ArgFunction)
1153 return Param == Arg;
1154
1155 // Noreturn and noexcept adjustment.
1156 QualType AdjustedParam;
1157 if (IsFunctionConversion(Param, Arg, AdjustedParam))
1158 return Arg == Context.getCanonicalType(AdjustedParam);
1159
1160 // FIXME: Compatible calling conventions.
1161
1162 return Param == Arg;
1163}
1164
1165/// Get the index of the first template parameter that was originally from the
1166/// innermost template-parameter-list. This is 0 except when we concatenate
1167/// the template parameter lists of a class template and a constructor template
1168/// when forming an implicit deduction guide.
1169static unsigned getFirstInnerIndex(FunctionTemplateDecl *FTD) {
1170 auto *Guide = dyn_cast<CXXDeductionGuideDecl>(FTD->getTemplatedDecl());
1171 if (!Guide || !Guide->isImplicit())
1172 return 0;
1173 return Guide->getDeducedTemplate()->getTemplateParameters()->size();
1174}
1175
1176/// Determine whether a type denotes a forwarding reference.
1177static bool isForwardingReference(QualType Param, unsigned FirstInnerIndex) {
1178 // C++1z [temp.deduct.call]p3:
1179 // A forwarding reference is an rvalue reference to a cv-unqualified
1180 // template parameter that does not represent a template parameter of a
1181 // class template.
1182 if (auto *ParamRef = Param->getAs<RValueReferenceType>()) {
1183 if (ParamRef->getPointeeType().getQualifiers())
1184 return false;
1185 auto *TypeParm = ParamRef->getPointeeType()->getAs<TemplateTypeParmType>();
1186 return TypeParm && TypeParm->getIndex() >= FirstInnerIndex;
1187 }
1188 return false;
1189}
1190
1191/// Deduce the template arguments by comparing the parameter type and
1192/// the argument type (C++ [temp.deduct.type]).
1193///
1194/// \param S the semantic analysis object within which we are deducing
1195///
1196/// \param TemplateParams the template parameters that we are deducing
1197///
1198/// \param ParamIn the parameter type
1199///
1200/// \param ArgIn the argument type
1201///
1202/// \param Info information about the template argument deduction itself
1203///
1204/// \param Deduced the deduced template arguments
1205///
1206/// \param TDF bitwise OR of the TemplateDeductionFlags bits that describe
1207/// how template argument deduction is performed.
1208///
1209/// \param PartialOrdering Whether we're performing template argument deduction
1210/// in the context of partial ordering (C++0x [temp.deduct.partial]).
1211///
1212/// \returns the result of template argument deduction so far. Note that a
1213/// "success" result means that template argument deduction has not yet failed,
1214/// but it may still fail, later, for other reasons.
1215static Sema::TemplateDeductionResult
1216DeduceTemplateArgumentsByTypeMatch(Sema &S,
1217 TemplateParameterList *TemplateParams,
1218 QualType ParamIn, QualType ArgIn,
1219 TemplateDeductionInfo &Info,
1220 SmallVectorImpl<DeducedTemplateArgument> &Deduced,
1221 unsigned TDF,
1222 bool PartialOrdering,
1223 bool DeducedFromArrayBound) {
1224 // We only want to look at the canonical types, since typedefs and
1225 // sugar are not part of template argument deduction.
1226 QualType Param = S.Context.getCanonicalType(ParamIn);
1227 QualType Arg = S.Context.getCanonicalType(ArgIn);
1228
1229 // If the argument type is a pack expansion, look at its pattern.
1230 // This isn't explicitly called out
1231 if (const PackExpansionType *ArgExpansion
1232 = dyn_cast<PackExpansionType>(Arg))
1233 Arg = ArgExpansion->getPattern();
1234
1235 if (PartialOrdering) {
1236 // C++11 [temp.deduct.partial]p5:
1237 // Before the partial ordering is done, certain transformations are
1238 // performed on the types used for partial ordering:
1239 // - If P is a reference type, P is replaced by the type referred to.
1240 const ReferenceType *ParamRef = Param->getAs<ReferenceType>();
1241 if (ParamRef)
1242 Param = ParamRef->getPointeeType();
1243
1244 // - If A is a reference type, A is replaced by the type referred to.
1245 const ReferenceType *ArgRef = Arg->getAs<ReferenceType>();
1246 if (ArgRef)
1247 Arg = ArgRef->getPointeeType();
1248
1249 if (ParamRef && ArgRef && S.Context.hasSameUnqualifiedType(Param, Arg)) {
1250 // C++11 [temp.deduct.partial]p9:
1251 // If, for a given type, deduction succeeds in both directions (i.e.,
1252 // the types are identical after the transformations above) and both
1253 // P and A were reference types [...]:
1254 // - if [one type] was an lvalue reference and [the other type] was
1255 // not, [the other type] is not considered to be at least as
1256 // specialized as [the first type]
1257 // - if [one type] is more cv-qualified than [the other type],
1258 // [the other type] is not considered to be at least as specialized
1259 // as [the first type]
1260 // Objective-C ARC adds:
1261 // - [one type] has non-trivial lifetime, [the other type] has
1262 // __unsafe_unretained lifetime, and the types are otherwise
1263 // identical
1264 //
1265 // A is "considered to be at least as specialized" as P iff deduction
1266 // succeeds, so we model this as a deduction failure. Note that
1267 // [the first type] is P and [the other type] is A here; the standard
1268 // gets this backwards.
1269 Qualifiers ParamQuals = Param.getQualifiers();
1270 Qualifiers ArgQuals = Arg.getQualifiers();
1271 if ((ParamRef->isLValueReferenceType() &&
1272 !ArgRef->isLValueReferenceType()) ||
1273 ParamQuals.isStrictSupersetOf(ArgQuals) ||
1274 (ParamQuals.hasNonTrivialObjCLifetime() &&
1275 ArgQuals.getObjCLifetime() == Qualifiers::OCL_ExplicitNone &&
1276 ParamQuals.withoutObjCLifetime() ==
1277 ArgQuals.withoutObjCLifetime())) {
1278 Info.FirstArg = TemplateArgument(ParamIn);
1279 Info.SecondArg = TemplateArgument(ArgIn);
1280 return Sema::TDK_NonDeducedMismatch;
1281 }
1282 }
1283
1284 // C++11 [temp.deduct.partial]p7:
1285 // Remove any top-level cv-qualifiers:
1286 // - If P is a cv-qualified type, P is replaced by the cv-unqualified
1287 // version of P.
1288 Param = Param.getUnqualifiedType();
1289 // - If A is a cv-qualified type, A is replaced by the cv-unqualified
1290 // version of A.
1291 Arg = Arg.getUnqualifiedType();
1292 } else {
1293 // C++0x [temp.deduct.call]p4 bullet 1:
1294 // - If the original P is a reference type, the deduced A (i.e., the type
1295 // referred to by the reference) can be more cv-qualified than the
1296 // transformed A.
1297 if (TDF & TDF_ParamWithReferenceType) {
1298 Qualifiers Quals;
1299 QualType UnqualParam = S.Context.getUnqualifiedArrayType(Param, Quals);
1300 Quals.setCVRQualifiers(Quals.getCVRQualifiers() &
1301 Arg.getCVRQualifiers());
1302 Param = S.Context.getQualifiedType(UnqualParam, Quals);
1303 }
1304
1305 if ((TDF & TDF_TopLevelParameterTypeList) && !Param->isFunctionType()) {
1306 // C++0x [temp.deduct.type]p10:
1307 // If P and A are function types that originated from deduction when
1308 // taking the address of a function template (14.8.2.2) or when deducing
1309 // template arguments from a function declaration (14.8.2.6) and Pi and
1310 // Ai are parameters of the top-level parameter-type-list of P and A,
1311 // respectively, Pi is adjusted if it is a forwarding reference and Ai
1312 // is an lvalue reference, in
1313 // which case the type of Pi is changed to be the template parameter
1314 // type (i.e., T&& is changed to simply T). [ Note: As a result, when
1315 // Pi is T&& and Ai is X&, the adjusted Pi will be T, causing T to be
1316 // deduced as X&. - end note ]
1317 TDF &= ~TDF_TopLevelParameterTypeList;
1318 if (isForwardingReference(Param, 0) && Arg->isLValueReferenceType())
1319 Param = Param->getPointeeType();
1320 }
1321 }
1322
1323 // C++ [temp.deduct.type]p9:
1324 // A template type argument T, a template template argument TT or a
1325 // template non-type argument i can be deduced if P and A have one of
1326 // the following forms:
1327 //
1328 // T
1329 // cv-list T
1330 if (const TemplateTypeParmType *TemplateTypeParm
1331 = Param->getAs<TemplateTypeParmType>()) {
1332 // Just skip any attempts to deduce from a placeholder type or a parameter
1333 // at a different depth.
1334 if (Arg->isPlaceholderType() ||
1335 Info.getDeducedDepth() != TemplateTypeParm->getDepth())
1336 return Sema::TDK_Success;
1337
1338 unsigned Index = TemplateTypeParm->getIndex();
1339 bool RecanonicalizeArg = false;
1340
1341 // If the argument type is an array type, move the qualifiers up to the
1342 // top level, so they can be matched with the qualifiers on the parameter.
1343 if (isa<ArrayType>(Arg)) {
1344 Qualifiers Quals;
1345 Arg = S.Context.getUnqualifiedArrayType(Arg, Quals);
1346 if (Quals) {
1347 Arg = S.Context.getQualifiedType(Arg, Quals);
1348 RecanonicalizeArg = true;
1349 }
1350 }
1351
1352 // The argument type can not be less qualified than the parameter
1353 // type.
1354 if (!(TDF & TDF_IgnoreQualifiers) &&
1355 hasInconsistentOrSupersetQualifiersOf(Param, Arg)) {
1356 Info.Param = cast<TemplateTypeParmDecl>(TemplateParams->getParam(Index));
1357 Info.FirstArg = TemplateArgument(Param);
1358 Info.SecondArg = TemplateArgument(Arg);
1359 return Sema::TDK_Underqualified;
1360 }
1361
1362 // Do not match a function type with a cv-qualified type.
1363 // http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#1584
1364 if (Arg->isFunctionType() && Param.hasQualifiers()) {
1365 return Sema::TDK_NonDeducedMismatch;
1366 }
1367
1368 assert(TemplateTypeParm->getDepth() == Info.getDeducedDepth() &&((TemplateTypeParm->getDepth() == Info.getDeducedDepth() &&
"saw template type parameter with wrong depth") ? static_cast
<void> (0) : __assert_fail ("TemplateTypeParm->getDepth() == Info.getDeducedDepth() && \"saw template type parameter with wrong depth\""
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 1369, __PRETTY_FUNCTION__))
1369 "saw template type parameter with wrong depth")((TemplateTypeParm->getDepth() == Info.getDeducedDepth() &&
"saw template type parameter with wrong depth") ? static_cast
<void> (0) : __assert_fail ("TemplateTypeParm->getDepth() == Info.getDeducedDepth() && \"saw template type parameter with wrong depth\""
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 1369, __PRETTY_FUNCTION__))
;
1370 assert(Arg != S.Context.OverloadTy && "Unresolved overloaded function")((Arg != S.Context.OverloadTy && "Unresolved overloaded function"
) ? static_cast<void> (0) : __assert_fail ("Arg != S.Context.OverloadTy && \"Unresolved overloaded function\""
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 1370, __PRETTY_FUNCTION__))
;
1371 QualType DeducedType = Arg;
1372
1373 // Remove any qualifiers on the parameter from the deduced type.
1374 // We checked the qualifiers for consistency above.
1375 Qualifiers DeducedQs = DeducedType.getQualifiers();
1376 Qualifiers ParamQs = Param.getQualifiers();
1377 DeducedQs.removeCVRQualifiers(ParamQs.getCVRQualifiers());
1378 if (ParamQs.hasObjCGCAttr())
1379 DeducedQs.removeObjCGCAttr();
1380 if (ParamQs.hasAddressSpace())
1381 DeducedQs.removeAddressSpace();
1382 if (ParamQs.hasObjCLifetime())
1383 DeducedQs.removeObjCLifetime();
1384
1385 // Objective-C ARC:
1386 // If template deduction would produce a lifetime qualifier on a type
1387 // that is not a lifetime type, template argument deduction fails.
1388 if (ParamQs.hasObjCLifetime() && !DeducedType->isObjCLifetimeType() &&
1389 !DeducedType->isDependentType()) {
1390 Info.Param = cast<TemplateTypeParmDecl>(TemplateParams->getParam(Index));
1391 Info.FirstArg = TemplateArgument(Param);
1392 Info.SecondArg = TemplateArgument(Arg);
1393 return Sema::TDK_Underqualified;
1394 }
1395
1396 // Objective-C ARC:
1397 // If template deduction would produce an argument type with lifetime type
1398 // but no lifetime qualifier, the __strong lifetime qualifier is inferred.
1399 if (S.getLangOpts().ObjCAutoRefCount &&
1400 DeducedType->isObjCLifetimeType() &&
1401 !DeducedQs.hasObjCLifetime())
1402 DeducedQs.setObjCLifetime(Qualifiers::OCL_Strong);
1403
1404 DeducedType = S.Context.getQualifiedType(DeducedType.getUnqualifiedType(),
1405 DeducedQs);
1406
1407 if (RecanonicalizeArg)
1408 DeducedType = S.Context.getCanonicalType(DeducedType);
1409
1410 DeducedTemplateArgument NewDeduced(DeducedType, DeducedFromArrayBound);
1411 DeducedTemplateArgument Result = checkDeducedTemplateArguments(S.Context,
1412 Deduced[Index],
1413 NewDeduced);
1414 if (Result.isNull()) {
1415 Info.Param = cast<TemplateTypeParmDecl>(TemplateParams->getParam(Index));
1416 Info.FirstArg = Deduced[Index];
1417 Info.SecondArg = NewDeduced;
1418 return Sema::TDK_Inconsistent;
1419 }
1420
1421 Deduced[Index] = Result;
1422 return Sema::TDK_Success;
1423 }
1424
1425 // Set up the template argument deduction information for a failure.
1426 Info.FirstArg = TemplateArgument(ParamIn);
1427 Info.SecondArg = TemplateArgument(ArgIn);
1428
1429 // If the parameter is an already-substituted template parameter
1430 // pack, do nothing: we don't know which of its arguments to look
1431 // at, so we have to wait until all of the parameter packs in this
1432 // expansion have arguments.
1433 if (isa<SubstTemplateTypeParmPackType>(Param))
1434 return Sema::TDK_Success;
1435
1436 // Check the cv-qualifiers on the parameter and argument types.
1437 CanQualType CanParam = S.Context.getCanonicalType(Param);
1438 CanQualType CanArg = S.Context.getCanonicalType(Arg);
1439 if (!(TDF & TDF_IgnoreQualifiers)) {
1440 if (TDF & TDF_ParamWithReferenceType) {
1441 if (hasInconsistentOrSupersetQualifiersOf(Param, Arg))
1442 return Sema::TDK_NonDeducedMismatch;
1443 } else if (TDF & TDF_ArgWithReferenceType) {
1444 // C++ [temp.deduct.conv]p4:
1445 // If the original A is a reference type, A can be more cv-qualified
1446 // than the deduced A
1447 if (!Arg.getQualifiers().compatiblyIncludes(Param.getQualifiers()))
1448 return Sema::TDK_NonDeducedMismatch;
1449
1450 // Strip out all extra qualifiers from the argument to figure out the
1451 // type we're converting to, prior to the qualification conversion.
1452 Qualifiers Quals;
1453 Arg = S.Context.getUnqualifiedArrayType(Arg, Quals);
1454 Arg = S.Context.getQualifiedType(Arg, Param.getQualifiers());
1455 } else if (!IsPossiblyOpaquelyQualifiedType(Param)) {
1456 if (Param.getCVRQualifiers() != Arg.getCVRQualifiers())
1457 return Sema::TDK_NonDeducedMismatch;
1458 }
1459
1460 // If the parameter type is not dependent, there is nothing to deduce.
1461 if (!Param->isDependentType()) {
1462 if (!(TDF & TDF_SkipNonDependent)) {
1463 bool NonDeduced =
1464 (TDF & TDF_AllowCompatibleFunctionType)
1465 ? !S.isSameOrCompatibleFunctionType(CanParam, CanArg)
1466 : Param != Arg;
1467 if (NonDeduced) {
1468 return Sema::TDK_NonDeducedMismatch;
1469 }
1470 }
1471 return Sema::TDK_Success;
1472 }
1473 } else if (!Param->isDependentType()) {
1474 CanQualType ParamUnqualType = CanParam.getUnqualifiedType(),
1475 ArgUnqualType = CanArg.getUnqualifiedType();
1476 bool Success =
1477 (TDF & TDF_AllowCompatibleFunctionType)
1478 ? S.isSameOrCompatibleFunctionType(ParamUnqualType, ArgUnqualType)
1479 : ParamUnqualType == ArgUnqualType;
1480 if (Success)
1481 return Sema::TDK_Success;
1482 }
1483
1484 switch (Param->getTypeClass()) {
1485 // Non-canonical types cannot appear here.
1486#define NON_CANONICAL_TYPE(Class, Base) \
1487 case Type::Class: llvm_unreachable("deducing non-canonical type: " #Class)::llvm::llvm_unreachable_internal("deducing non-canonical type: "
#Class, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 1487)
;
1488#define TYPE(Class, Base)
1489#include "clang/AST/TypeNodes.def"
1490
1491 case Type::TemplateTypeParm:
1492 case Type::SubstTemplateTypeParmPack:
1493 llvm_unreachable("Type nodes handled above")::llvm::llvm_unreachable_internal("Type nodes handled above",
"/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 1493)
;
1494
1495 // These types cannot be dependent, so simply check whether the types are
1496 // the same.
1497 case Type::Builtin:
1498 case Type::VariableArray:
1499 case Type::Vector:
1500 case Type::FunctionNoProto:
1501 case Type::Record:
1502 case Type::Enum:
1503 case Type::ObjCObject:
1504 case Type::ObjCInterface:
1505 case Type::ObjCObjectPointer:
1506 if (TDF & TDF_SkipNonDependent)
1507 return Sema::TDK_Success;
1508
1509 if (TDF & TDF_IgnoreQualifiers) {
1510 Param = Param.getUnqualifiedType();
1511 Arg = Arg.getUnqualifiedType();
1512 }
1513
1514 return Param == Arg? Sema::TDK_Success : Sema::TDK_NonDeducedMismatch;
1515
1516 // _Complex T [placeholder extension]
1517 case Type::Complex:
1518 if (const ComplexType *ComplexArg = Arg->getAs<ComplexType>())
1519 return DeduceTemplateArgumentsByTypeMatch(S, TemplateParams,
1520 cast<ComplexType>(Param)->getElementType(),
1521 ComplexArg->getElementType(),
1522 Info, Deduced, TDF);
1523
1524 return Sema::TDK_NonDeducedMismatch;
1525
1526 // _Atomic T [extension]
1527 case Type::Atomic:
1528 if (const AtomicType *AtomicArg = Arg->getAs<AtomicType>())
1529 return DeduceTemplateArgumentsByTypeMatch(S, TemplateParams,
1530 cast<AtomicType>(Param)->getValueType(),
1531 AtomicArg->getValueType(),
1532 Info, Deduced, TDF);
1533
1534 return Sema::TDK_NonDeducedMismatch;
1535
1536 // T *
1537 case Type::Pointer: {
1538 QualType PointeeType;
1539 if (const PointerType *PointerArg = Arg->getAs<PointerType>()) {
1540 PointeeType = PointerArg->getPointeeType();
1541 } else if (const ObjCObjectPointerType *PointerArg
1542 = Arg->getAs<ObjCObjectPointerType>()) {
1543 PointeeType = PointerArg->getPointeeType();
1544 } else {
1545 return Sema::TDK_NonDeducedMismatch;
1546 }
1547
1548 unsigned SubTDF = TDF & (TDF_IgnoreQualifiers | TDF_DerivedClass);
1549 return DeduceTemplateArgumentsByTypeMatch(S, TemplateParams,
1550 cast<PointerType>(Param)->getPointeeType(),
1551 PointeeType,
1552 Info, Deduced, SubTDF);
1553 }
1554
1555 // T &
1556 case Type::LValueReference: {
1557 const LValueReferenceType *ReferenceArg =
1558 Arg->getAs<LValueReferenceType>();
1559 if (!ReferenceArg)
1560 return Sema::TDK_NonDeducedMismatch;
1561
1562 return DeduceTemplateArgumentsByTypeMatch(S, TemplateParams,
1563 cast<LValueReferenceType>(Param)->getPointeeType(),
1564 ReferenceArg->getPointeeType(), Info, Deduced, 0);
1565 }
1566
1567 // T && [C++0x]
1568 case Type::RValueReference: {
1569 const RValueReferenceType *ReferenceArg =
1570 Arg->getAs<RValueReferenceType>();
1571 if (!ReferenceArg)
1572 return Sema::TDK_NonDeducedMismatch;
1573
1574 return DeduceTemplateArgumentsByTypeMatch(S, TemplateParams,
1575 cast<RValueReferenceType>(Param)->getPointeeType(),
1576 ReferenceArg->getPointeeType(),
1577 Info, Deduced, 0);
1578 }
1579
1580 // T [] (implied, but not stated explicitly)
1581 case Type::IncompleteArray: {
1582 const IncompleteArrayType *IncompleteArrayArg =
1583 S.Context.getAsIncompleteArrayType(Arg);
1584 if (!IncompleteArrayArg)
1585 return Sema::TDK_NonDeducedMismatch;
1586
1587 unsigned SubTDF = TDF & TDF_IgnoreQualifiers;
1588 return DeduceTemplateArgumentsByTypeMatch(S, TemplateParams,
1589 S.Context.getAsIncompleteArrayType(Param)->getElementType(),
1590 IncompleteArrayArg->getElementType(),
1591 Info, Deduced, SubTDF);
1592 }
1593
1594 // T [integer-constant]
1595 case Type::ConstantArray: {
1596 const ConstantArrayType *ConstantArrayArg =
1597 S.Context.getAsConstantArrayType(Arg);
1598 if (!ConstantArrayArg)
1599 return Sema::TDK_NonDeducedMismatch;
1600
1601 const ConstantArrayType *ConstantArrayParm =
1602 S.Context.getAsConstantArrayType(Param);
1603 if (ConstantArrayArg->getSize() != ConstantArrayParm->getSize())
1604 return Sema::TDK_NonDeducedMismatch;
1605
1606 unsigned SubTDF = TDF & TDF_IgnoreQualifiers;
1607 return DeduceTemplateArgumentsByTypeMatch(S, TemplateParams,
1608 ConstantArrayParm->getElementType(),
1609 ConstantArrayArg->getElementType(),
1610 Info, Deduced, SubTDF);
1611 }
1612
1613 // type [i]
1614 case Type::DependentSizedArray: {
1615 const ArrayType *ArrayArg = S.Context.getAsArrayType(Arg);
1616 if (!ArrayArg)
1617 return Sema::TDK_NonDeducedMismatch;
1618
1619 unsigned SubTDF = TDF & TDF_IgnoreQualifiers;
1620
1621 // Check the element type of the arrays
1622 const DependentSizedArrayType *DependentArrayParm
1623 = S.Context.getAsDependentSizedArrayType(Param);
1624 if (Sema::TemplateDeductionResult Result
1625 = DeduceTemplateArgumentsByTypeMatch(S, TemplateParams,
1626 DependentArrayParm->getElementType(),
1627 ArrayArg->getElementType(),
1628 Info, Deduced, SubTDF))
1629 return Result;
1630
1631 // Determine the array bound is something we can deduce.
1632 NonTypeTemplateParmDecl *NTTP
1633 = getDeducedParameterFromExpr(Info, DependentArrayParm->getSizeExpr());
1634 if (!NTTP)
1635 return Sema::TDK_Success;
1636
1637 // We can perform template argument deduction for the given non-type
1638 // template parameter.
1639 assert(NTTP->getDepth() == Info.getDeducedDepth() &&((NTTP->getDepth() == Info.getDeducedDepth() && "saw non-type template parameter with wrong depth"
) ? static_cast<void> (0) : __assert_fail ("NTTP->getDepth() == Info.getDeducedDepth() && \"saw non-type template parameter with wrong depth\""
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 1640, __PRETTY_FUNCTION__))
1640 "saw non-type template parameter with wrong depth")((NTTP->getDepth() == Info.getDeducedDepth() && "saw non-type template parameter with wrong depth"
) ? static_cast<void> (0) : __assert_fail ("NTTP->getDepth() == Info.getDeducedDepth() && \"saw non-type template parameter with wrong depth\""
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 1640, __PRETTY_FUNCTION__))
;
1641 if (const ConstantArrayType *ConstantArrayArg
1642 = dyn_cast<ConstantArrayType>(ArrayArg)) {
1643 llvm::APSInt Size(ConstantArrayArg->getSize());
1644 return DeduceNonTypeTemplateArgument(S, TemplateParams, NTTP, Size,
1645 S.Context.getSizeType(),
1646 /*ArrayBound=*/true,
1647 Info, Deduced);
1648 }
1649 if (const DependentSizedArrayType *DependentArrayArg
1650 = dyn_cast<DependentSizedArrayType>(ArrayArg))
1651 if (DependentArrayArg->getSizeExpr())
1652 return DeduceNonTypeTemplateArgument(S, TemplateParams, NTTP,
1653 DependentArrayArg->getSizeExpr(),
1654 Info, Deduced);
1655
1656 // Incomplete type does not match a dependently-sized array type
1657 return Sema::TDK_NonDeducedMismatch;
1658 }
1659
1660 // type(*)(T)
1661 // T(*)()
1662 // T(*)(T)
1663 case Type::FunctionProto: {
1664 unsigned SubTDF = TDF & TDF_TopLevelParameterTypeList;
1665 const FunctionProtoType *FunctionProtoArg =
1666 dyn_cast<FunctionProtoType>(Arg);
1667 if (!FunctionProtoArg)
1668 return Sema::TDK_NonDeducedMismatch;
1669
1670 const FunctionProtoType *FunctionProtoParam =
1671 cast<FunctionProtoType>(Param);
1672
1673 if (FunctionProtoParam->getMethodQuals()
1674 != FunctionProtoArg->getMethodQuals() ||
1675 FunctionProtoParam->getRefQualifier()
1676 != FunctionProtoArg->getRefQualifier() ||
1677 FunctionProtoParam->isVariadic() != FunctionProtoArg->isVariadic())
1678 return Sema::TDK_NonDeducedMismatch;
1679
1680 // Check return types.
1681 if (auto Result = DeduceTemplateArgumentsByTypeMatch(
1682 S, TemplateParams, FunctionProtoParam->getReturnType(),
1683 FunctionProtoArg->getReturnType(), Info, Deduced, 0))
1684 return Result;
1685
1686 // Check parameter types.
1687 if (auto Result = DeduceTemplateArguments(
1688 S, TemplateParams, FunctionProtoParam->param_type_begin(),
1689 FunctionProtoParam->getNumParams(),
1690 FunctionProtoArg->param_type_begin(),
1691 FunctionProtoArg->getNumParams(), Info, Deduced, SubTDF))
1692 return Result;
1693
1694 if (TDF & TDF_AllowCompatibleFunctionType)
1695 return Sema::TDK_Success;
1696
1697 // FIXME: Per core-2016/10/1019 (no corresponding core issue yet), permit
1698 // deducing through the noexcept-specifier if it's part of the canonical
1699 // type. libstdc++ relies on this.
1700 Expr *NoexceptExpr = FunctionProtoParam->getNoexceptExpr();
1701 if (NonTypeTemplateParmDecl *NTTP =
1702 NoexceptExpr ? getDeducedParameterFromExpr(Info, NoexceptExpr)
1703 : nullptr) {
1704 assert(NTTP->getDepth() == Info.getDeducedDepth() &&((NTTP->getDepth() == Info.getDeducedDepth() && "saw non-type template parameter with wrong depth"
) ? static_cast<void> (0) : __assert_fail ("NTTP->getDepth() == Info.getDeducedDepth() && \"saw non-type template parameter with wrong depth\""
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 1705, __PRETTY_FUNCTION__))
1705 "saw non-type template parameter with wrong depth")((NTTP->getDepth() == Info.getDeducedDepth() && "saw non-type template parameter with wrong depth"
) ? static_cast<void> (0) : __assert_fail ("NTTP->getDepth() == Info.getDeducedDepth() && \"saw non-type template parameter with wrong depth\""
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 1705, __PRETTY_FUNCTION__))
;
1706
1707 llvm::APSInt Noexcept(1);
1708 switch (FunctionProtoArg->canThrow()) {
1709 case CT_Cannot:
1710 Noexcept = 1;
1711 LLVM_FALLTHROUGH[[clang::fallthrough]];
1712
1713 case CT_Can:
1714 // We give E in noexcept(E) the "deduced from array bound" treatment.
1715 // FIXME: Should we?
1716 return DeduceNonTypeTemplateArgument(
1717 S, TemplateParams, NTTP, Noexcept, S.Context.BoolTy,
1718 /*ArrayBound*/true, Info, Deduced);
1719
1720 case CT_Dependent:
1721 if (Expr *ArgNoexceptExpr = FunctionProtoArg->getNoexceptExpr())
1722 return DeduceNonTypeTemplateArgument(
1723 S, TemplateParams, NTTP, ArgNoexceptExpr, Info, Deduced);
1724 // Can't deduce anything from throw(T...).
1725 break;
1726 }
1727 }
1728 // FIXME: Detect non-deduced exception specification mismatches?
1729 //
1730 // Careful about [temp.deduct.call] and [temp.deduct.conv], which allow
1731 // top-level differences in noexcept-specifications.
1732
1733 return Sema::TDK_Success;
1734 }
1735
1736 case Type::InjectedClassName:
1737 // Treat a template's injected-class-name as if the template
1738 // specialization type had been used.
1739 Param = cast<InjectedClassNameType>(Param)
1740 ->getInjectedSpecializationType();
1741 assert(isa<TemplateSpecializationType>(Param) &&((isa<TemplateSpecializationType>(Param) && "injected class name is not a template specialization type"
) ? static_cast<void> (0) : __assert_fail ("isa<TemplateSpecializationType>(Param) && \"injected class name is not a template specialization type\""
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 1742, __PRETTY_FUNCTION__))
1742 "injected class name is not a template specialization type")((isa<TemplateSpecializationType>(Param) && "injected class name is not a template specialization type"
) ? static_cast<void> (0) : __assert_fail ("isa<TemplateSpecializationType>(Param) && \"injected class name is not a template specialization type\""
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 1742, __PRETTY_FUNCTION__))
;
1743 LLVM_FALLTHROUGH[[clang::fallthrough]];
1744
1745 // template-name<T> (where template-name refers to a class template)
1746 // template-name<i>
1747 // TT<T>
1748 // TT<i>
1749 // TT<>
1750 case Type::TemplateSpecialization: {
1751 const TemplateSpecializationType *SpecParam =
1752 cast<TemplateSpecializationType>(Param);
1753
1754 // When Arg cannot be a derived class, we can just try to deduce template
1755 // arguments from the template-id.
1756 const RecordType *RecordT = Arg->getAs<RecordType>();
1757 if (!(TDF & TDF_DerivedClass) || !RecordT)
1758 return DeduceTemplateArguments(S, TemplateParams, SpecParam, Arg, Info,
1759 Deduced);
1760
1761 SmallVector<DeducedTemplateArgument, 8> DeducedOrig(Deduced.begin(),
1762 Deduced.end());
1763
1764 Sema::TemplateDeductionResult Result = DeduceTemplateArguments(
1765 S, TemplateParams, SpecParam, Arg, Info, Deduced);
1766
1767 if (Result == Sema::TDK_Success)
1768 return Result;
1769
1770 // We cannot inspect base classes as part of deduction when the type
1771 // is incomplete, so either instantiate any templates necessary to
1772 // complete the type, or skip over it if it cannot be completed.
1773 if (!S.isCompleteType(Info.getLocation(), Arg))
1774 return Result;
1775
1776 // C++14 [temp.deduct.call] p4b3:
1777 // If P is a class and P has the form simple-template-id, then the
1778 // transformed A can be a derived class of the deduced A. Likewise if
1779 // P is a pointer to a class of the form simple-template-id, the
1780 // transformed A can be a pointer to a derived class pointed to by the
1781 // deduced A.
1782 //
1783 // These alternatives are considered only if type deduction would
1784 // otherwise fail. If they yield more than one possible deduced A, the
1785 // type deduction fails.
1786
1787 // Reset the incorrectly deduced argument from above.
1788 Deduced = DeducedOrig;
1789
1790 // Use data recursion to crawl through the list of base classes.
1791 // Visited contains the set of nodes we have already visited, while
1792 // ToVisit is our stack of records that we still need to visit.
1793 llvm::SmallPtrSet<const RecordType *, 8> Visited;
1794 SmallVector<const RecordType *, 8> ToVisit;
1795 ToVisit.push_back(RecordT);
1796 bool Successful = false;
1797 SmallVector<DeducedTemplateArgument, 8> SuccessfulDeduced;
1798 while (!ToVisit.empty()) {
1799 // Retrieve the next class in the inheritance hierarchy.
1800 const RecordType *NextT = ToVisit.pop_back_val();
1801
1802 // If we have already seen this type, skip it.
1803 if (!Visited.insert(NextT).second)
1804 continue;
1805
1806 // If this is a base class, try to perform template argument
1807 // deduction from it.
1808 if (NextT != RecordT) {
1809 TemplateDeductionInfo BaseInfo(Info.getLocation());
1810 Sema::TemplateDeductionResult BaseResult =
1811 DeduceTemplateArguments(S, TemplateParams, SpecParam,
1812 QualType(NextT, 0), BaseInfo, Deduced);
1813
1814 // If template argument deduction for this base was successful,
1815 // note that we had some success. Otherwise, ignore any deductions
1816 // from this base class.
1817 if (BaseResult == Sema::TDK_Success) {
1818 // If we've already seen some success, then deduction fails due to
1819 // an ambiguity (temp.deduct.call p5).
1820 if (Successful)
1821 return Sema::TDK_MiscellaneousDeductionFailure;
1822
1823 Successful = true;
1824 std::swap(SuccessfulDeduced, Deduced);
1825
1826 Info.Param = BaseInfo.Param;
1827 Info.FirstArg = BaseInfo.FirstArg;
1828 Info.SecondArg = BaseInfo.SecondArg;
1829 }
1830
1831 Deduced = DeducedOrig;
1832 }
1833
1834 // Visit base classes
1835 CXXRecordDecl *Next = cast<CXXRecordDecl>(NextT->getDecl());
1836 for (const auto &Base : Next->bases()) {
1837 assert(Base.getType()->isRecordType() &&((Base.getType()->isRecordType() && "Base class that isn't a record?"
) ? static_cast<void> (0) : __assert_fail ("Base.getType()->isRecordType() && \"Base class that isn't a record?\""
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 1838, __PRETTY_FUNCTION__))
1838 "Base class that isn't a record?")((Base.getType()->isRecordType() && "Base class that isn't a record?"
) ? static_cast<void> (0) : __assert_fail ("Base.getType()->isRecordType() && \"Base class that isn't a record?\""
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 1838, __PRETTY_FUNCTION__))
;
1839 ToVisit.push_back(Base.getType()->getAs<RecordType>());
1840 }
1841 }
1842
1843 if (Successful) {
1844 std::swap(SuccessfulDeduced, Deduced);
1845 return Sema::TDK_Success;
1846 }
1847
1848 return Result;
1849 }
1850
1851 // T type::*
1852 // T T::*
1853 // T (type::*)()
1854 // type (T::*)()
1855 // type (type::*)(T)
1856 // type (T::*)(T)
1857 // T (type::*)(T)
1858 // T (T::*)()
1859 // T (T::*)(T)
1860 case Type::MemberPointer: {
1861 const MemberPointerType *MemPtrParam = cast<MemberPointerType>(Param);
1862 const MemberPointerType *MemPtrArg = dyn_cast<MemberPointerType>(Arg);
1863 if (!MemPtrArg)
1864 return Sema::TDK_NonDeducedMismatch;
1865
1866 QualType ParamPointeeType = MemPtrParam->getPointeeType();
1867 if (ParamPointeeType->isFunctionType())
1868 S.adjustMemberFunctionCC(ParamPointeeType, /*IsStatic=*/true,
1869 /*IsCtorOrDtor=*/false, Info.getLocation());
1870 QualType ArgPointeeType = MemPtrArg->getPointeeType();
1871 if (ArgPointeeType->isFunctionType())
1872 S.adjustMemberFunctionCC(ArgPointeeType, /*IsStatic=*/true,
1873 /*IsCtorOrDtor=*/false, Info.getLocation());
1874
1875 if (Sema::TemplateDeductionResult Result
1876 = DeduceTemplateArgumentsByTypeMatch(S, TemplateParams,
1877 ParamPointeeType,
1878 ArgPointeeType,
1879 Info, Deduced,
1880 TDF & TDF_IgnoreQualifiers))
1881 return Result;
1882
1883 return DeduceTemplateArgumentsByTypeMatch(S, TemplateParams,
1884 QualType(MemPtrParam->getClass(), 0),
1885 QualType(MemPtrArg->getClass(), 0),
1886 Info, Deduced,
1887 TDF & TDF_IgnoreQualifiers);
1888 }
1889
1890 // (clang extension)
1891 //
1892 // type(^)(T)
1893 // T(^)()
1894 // T(^)(T)
1895 case Type::BlockPointer: {
1896 const BlockPointerType *BlockPtrParam = cast<BlockPointerType>(Param);
1897 const BlockPointerType *BlockPtrArg = dyn_cast<BlockPointerType>(Arg);
1898
1899 if (!BlockPtrArg)
1900 return Sema::TDK_NonDeducedMismatch;
1901
1902 return DeduceTemplateArgumentsByTypeMatch(S, TemplateParams,
1903 BlockPtrParam->getPointeeType(),
1904 BlockPtrArg->getPointeeType(),
1905 Info, Deduced, 0);
1906 }
1907
1908 // (clang extension)
1909 //
1910 // T __attribute__(((ext_vector_type(<integral constant>))))
1911 case Type::ExtVector: {
1912 const ExtVectorType *VectorParam = cast<ExtVectorType>(Param);
1913 if (const ExtVectorType *VectorArg = dyn_cast<ExtVectorType>(Arg)) {
1914 // Make sure that the vectors have the same number of elements.
1915 if (VectorParam->getNumElements() != VectorArg->getNumElements())
1916 return Sema::TDK_NonDeducedMismatch;
1917
1918 // Perform deduction on the element types.
1919 return DeduceTemplateArgumentsByTypeMatch(S, TemplateParams,
1920 VectorParam->getElementType(),
1921 VectorArg->getElementType(),
1922 Info, Deduced, TDF);
1923 }
1924
1925 if (const DependentSizedExtVectorType *VectorArg
1926 = dyn_cast<DependentSizedExtVectorType>(Arg)) {
1927 // We can't check the number of elements, since the argument has a
1928 // dependent number of elements. This can only occur during partial
1929 // ordering.
1930
1931 // Perform deduction on the element types.
1932 return DeduceTemplateArgumentsByTypeMatch(S, TemplateParams,
1933 VectorParam->getElementType(),
1934 VectorArg->getElementType(),
1935 Info, Deduced, TDF);
1936 }
1937
1938 return Sema::TDK_NonDeducedMismatch;
1939 }
1940
1941 case Type::DependentVector: {
1942 const auto *VectorParam = cast<DependentVectorType>(Param);
1943
1944 if (const auto *VectorArg = dyn_cast<VectorType>(Arg)) {
1945 // Perform deduction on the element types.
1946 if (Sema::TemplateDeductionResult Result =
1947 DeduceTemplateArgumentsByTypeMatch(
1948 S, TemplateParams, VectorParam->getElementType(),
1949 VectorArg->getElementType(), Info, Deduced, TDF))
1950 return Result;
1951
1952 // Perform deduction on the vector size, if we can.
1953 NonTypeTemplateParmDecl *NTTP =
1954 getDeducedParameterFromExpr(Info, VectorParam->getSizeExpr());
1955 if (!NTTP)
1956 return Sema::TDK_Success;
1957
1958 llvm::APSInt ArgSize(S.Context.getTypeSize(S.Context.IntTy), false);
1959 ArgSize = VectorArg->getNumElements();
1960 // Note that we use the "array bound" rules here; just like in that
1961 // case, we don't have any particular type for the vector size, but
1962 // we can provide one if necessary.
1963 return DeduceNonTypeTemplateArgument(S, TemplateParams, NTTP, ArgSize,
1964 S.Context.UnsignedIntTy, true,
1965 Info, Deduced);
1966 }
1967
1968 if (const auto *VectorArg = dyn_cast<DependentVectorType>(Arg)) {
1969 // Perform deduction on the element types.
1970 if (Sema::TemplateDeductionResult Result =
1971 DeduceTemplateArgumentsByTypeMatch(
1972 S, TemplateParams, VectorParam->getElementType(),
1973 VectorArg->getElementType(), Info, Deduced, TDF))
1974 return Result;
1975
1976 // Perform deduction on the vector size, if we can.
1977 NonTypeTemplateParmDecl *NTTP = getDeducedParameterFromExpr(
1978 Info, VectorParam->getSizeExpr());
1979 if (!NTTP)
1980 return Sema::TDK_Success;
1981
1982 return DeduceNonTypeTemplateArgument(
1983 S, TemplateParams, NTTP, VectorArg->getSizeExpr(), Info, Deduced);
1984 }
1985
1986 return Sema::TDK_NonDeducedMismatch;
1987 }
1988
1989 // (clang extension)
1990 //
1991 // T __attribute__(((ext_vector_type(N))))
1992 case Type::DependentSizedExtVector: {
1993 const DependentSizedExtVectorType *VectorParam
1994 = cast<DependentSizedExtVectorType>(Param);
1995
1996 if (const ExtVectorType *VectorArg = dyn_cast<ExtVectorType>(Arg)) {
1997 // Perform deduction on the element types.
1998 if (Sema::TemplateDeductionResult Result
1999 = DeduceTemplateArgumentsByTypeMatch(S, TemplateParams,
2000 VectorParam->getElementType(),
2001 VectorArg->getElementType(),
2002 Info, Deduced, TDF))
2003 return Result;
2004
2005 // Perform deduction on the vector size, if we can.
2006 NonTypeTemplateParmDecl *NTTP
2007 = getDeducedParameterFromExpr(Info, VectorParam->getSizeExpr());
2008 if (!NTTP)
2009 return Sema::TDK_Success;
2010
2011 llvm::APSInt ArgSize(S.Context.getTypeSize(S.Context.IntTy), false);
2012 ArgSize = VectorArg->getNumElements();
2013 // Note that we use the "array bound" rules here; just like in that
2014 // case, we don't have any particular type for the vector size, but
2015 // we can provide one if necessary.
2016 return DeduceNonTypeTemplateArgument(S, TemplateParams, NTTP, ArgSize,
2017 S.Context.IntTy, true, Info,
2018 Deduced);
2019 }
2020
2021 if (const DependentSizedExtVectorType *VectorArg
2022 = dyn_cast<DependentSizedExtVectorType>(Arg)) {
2023 // Perform deduction on the element types.
2024 if (Sema::TemplateDeductionResult Result
2025 = DeduceTemplateArgumentsByTypeMatch(S, TemplateParams,
2026 VectorParam->getElementType(),
2027 VectorArg->getElementType(),
2028 Info, Deduced, TDF))
2029 return Result;
2030
2031 // Perform deduction on the vector size, if we can.
2032 NonTypeTemplateParmDecl *NTTP
2033 = getDeducedParameterFromExpr(Info, VectorParam->getSizeExpr());
2034 if (!NTTP)
2035 return Sema::TDK_Success;
2036
2037 return DeduceNonTypeTemplateArgument(S, TemplateParams, NTTP,
2038 VectorArg->getSizeExpr(),
2039 Info, Deduced);
2040 }
2041
2042 return Sema::TDK_NonDeducedMismatch;
2043 }
2044
2045 // (clang extension)
2046 //
2047 // T __attribute__(((address_space(N))))
2048 case Type::DependentAddressSpace: {
2049 const DependentAddressSpaceType *AddressSpaceParam =
2050 cast<DependentAddressSpaceType>(Param);
2051
2052 if (const DependentAddressSpaceType *AddressSpaceArg =
2053 dyn_cast<DependentAddressSpaceType>(Arg)) {
2054 // Perform deduction on the pointer type.
2055 if (Sema::TemplateDeductionResult Result =
2056 DeduceTemplateArgumentsByTypeMatch(
2057 S, TemplateParams, AddressSpaceParam->getPointeeType(),
2058 AddressSpaceArg->getPointeeType(), Info, Deduced, TDF))
2059 return Result;
2060
2061 // Perform deduction on the address space, if we can.
2062 NonTypeTemplateParmDecl *NTTP = getDeducedParameterFromExpr(
2063 Info, AddressSpaceParam->getAddrSpaceExpr());
2064 if (!NTTP)
2065 return Sema::TDK_Success;
2066
2067 return DeduceNonTypeTemplateArgument(
2068 S, TemplateParams, NTTP, AddressSpaceArg->getAddrSpaceExpr(), Info,
2069 Deduced);
2070 }
2071
2072 if (isTargetAddressSpace(Arg.getAddressSpace())) {
2073 llvm::APSInt ArgAddressSpace(S.Context.getTypeSize(S.Context.IntTy),
2074 false);
2075 ArgAddressSpace = toTargetAddressSpace(Arg.getAddressSpace());
2076
2077 // Perform deduction on the pointer types.
2078 if (Sema::TemplateDeductionResult Result =
2079 DeduceTemplateArgumentsByTypeMatch(
2080 S, TemplateParams, AddressSpaceParam->getPointeeType(),
2081 S.Context.removeAddrSpaceQualType(Arg), Info, Deduced, TDF))
2082 return Result;
2083
2084 // Perform deduction on the address space, if we can.
2085 NonTypeTemplateParmDecl *NTTP = getDeducedParameterFromExpr(
2086 Info, AddressSpaceParam->getAddrSpaceExpr());
2087 if (!NTTP)
2088 return Sema::TDK_Success;
2089
2090 return DeduceNonTypeTemplateArgument(S, TemplateParams, NTTP,
2091 ArgAddressSpace, S.Context.IntTy,
2092 true, Info, Deduced);
2093 }
2094
2095 return Sema::TDK_NonDeducedMismatch;
2096 }
2097
2098 case Type::TypeOfExpr:
2099 case Type::TypeOf:
2100 case Type::DependentName:
2101 case Type::UnresolvedUsing:
2102 case Type::Decltype:
2103 case Type::UnaryTransform:
2104 case Type::Auto:
2105 case Type::DeducedTemplateSpecialization:
2106 case Type::DependentTemplateSpecialization:
2107 case Type::PackExpansion:
2108 case Type::Pipe:
2109 // No template argument deduction for these types
2110 return Sema::TDK_Success;
2111 }
2112
2113 llvm_unreachable("Invalid Type Class!")::llvm::llvm_unreachable_internal("Invalid Type Class!", "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 2113)
;
2114}
2115
2116static Sema::TemplateDeductionResult
2117DeduceTemplateArguments(Sema &S,
2118 TemplateParameterList *TemplateParams,
2119 const TemplateArgument &Param,
2120 TemplateArgument Arg,
2121 TemplateDeductionInfo &Info,
2122 SmallVectorImpl<DeducedTemplateArgument> &Deduced) {
2123 // If the template argument is a pack expansion, perform template argument
2124 // deduction against the pattern of that expansion. This only occurs during
2125 // partial ordering.
2126 if (Arg.isPackExpansion())
2127 Arg = Arg.getPackExpansionPattern();
2128
2129 switch (Param.getKind()) {
2130 case TemplateArgument::Null:
2131 llvm_unreachable("Null template argument in parameter list")::llvm::llvm_unreachable_internal("Null template argument in parameter list"
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 2131)
;
2132
2133 case TemplateArgument::Type:
2134 if (Arg.getKind() == TemplateArgument::Type)
2135 return DeduceTemplateArgumentsByTypeMatch(S, TemplateParams,
2136 Param.getAsType(),
2137 Arg.getAsType(),
2138 Info, Deduced, 0);
2139 Info.FirstArg = Param;
2140 Info.SecondArg = Arg;
2141 return Sema::TDK_NonDeducedMismatch;
2142
2143 case TemplateArgument::Template:
2144 if (Arg.getKind() == TemplateArgument::Template)
2145 return DeduceTemplateArguments(S, TemplateParams,
2146 Param.getAsTemplate(),
2147 Arg.getAsTemplate(), Info, Deduced);
2148 Info.FirstArg = Param;
2149 Info.SecondArg = Arg;
2150 return Sema::TDK_NonDeducedMismatch;
2151
2152 case TemplateArgument::TemplateExpansion:
2153 llvm_unreachable("caller should handle pack expansions")::llvm::llvm_unreachable_internal("caller should handle pack expansions"
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 2153)
;
2154
2155 case TemplateArgument::Declaration:
2156 if (Arg.getKind() == TemplateArgument::Declaration &&
2157 isSameDeclaration(Param.getAsDecl(), Arg.getAsDecl()))
2158 return Sema::TDK_Success;
2159
2160 Info.FirstArg = Param;
2161 Info.SecondArg = Arg;
2162 return Sema::TDK_NonDeducedMismatch;
2163
2164 case TemplateArgument::NullPtr:
2165 if (Arg.getKind() == TemplateArgument::NullPtr &&
2166 S.Context.hasSameType(Param.getNullPtrType(), Arg.getNullPtrType()))
2167 return Sema::TDK_Success;
2168
2169 Info.FirstArg = Param;
2170 Info.SecondArg = Arg;
2171 return Sema::TDK_NonDeducedMismatch;
2172
2173 case TemplateArgument::Integral:
2174 if (Arg.getKind() == TemplateArgument::Integral) {
2175 if (hasSameExtendedValue(Param.getAsIntegral(), Arg.getAsIntegral()))
2176 return Sema::TDK_Success;
2177
2178 Info.FirstArg = Param;
2179 Info.SecondArg = Arg;
2180 return Sema::TDK_NonDeducedMismatch;
2181 }
2182
2183 if (Arg.getKind() == TemplateArgument::Expression) {
2184 Info.FirstArg = Param;
2185 Info.SecondArg = Arg;
2186 return Sema::TDK_NonDeducedMismatch;
2187 }
2188
2189 Info.FirstArg = Param;
2190 Info.SecondArg = Arg;
2191 return Sema::TDK_NonDeducedMismatch;
2192
2193 case TemplateArgument::Expression:
2194 if (NonTypeTemplateParmDecl *NTTP
2195 = getDeducedParameterFromExpr(Info, Param.getAsExpr())) {
2196 if (Arg.getKind() == TemplateArgument::Integral)
2197 return DeduceNonTypeTemplateArgument(S, TemplateParams, NTTP,
2198 Arg.getAsIntegral(),
2199 Arg.getIntegralType(),
2200 /*ArrayBound=*/false,
2201 Info, Deduced);
2202 if (Arg.getKind() == TemplateArgument::NullPtr)
2203 return DeduceNullPtrTemplateArgument(S, TemplateParams, NTTP,
2204 Arg.getNullPtrType(),
2205 Info, Deduced);
2206 if (Arg.getKind() == TemplateArgument::Expression)
2207 return DeduceNonTypeTemplateArgument(S, TemplateParams, NTTP,
2208 Arg.getAsExpr(), Info, Deduced);
2209 if (Arg.getKind() == TemplateArgument::Declaration)
2210 return DeduceNonTypeTemplateArgument(S, TemplateParams, NTTP,
2211 Arg.getAsDecl(),
2212 Arg.getParamTypeForDecl(),
2213 Info, Deduced);
2214
2215 Info.FirstArg = Param;
2216 Info.SecondArg = Arg;
2217 return Sema::TDK_NonDeducedMismatch;
2218 }
2219
2220 // Can't deduce anything, but that's okay.
2221 return Sema::TDK_Success;
2222
2223 case TemplateArgument::Pack:
2224 llvm_unreachable("Argument packs should be expanded by the caller!")::llvm::llvm_unreachable_internal("Argument packs should be expanded by the caller!"
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 2224)
;
2225 }
2226
2227 llvm_unreachable("Invalid TemplateArgument Kind!")::llvm::llvm_unreachable_internal("Invalid TemplateArgument Kind!"
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 2227)
;
2228}
2229
2230/// Determine whether there is a template argument to be used for
2231/// deduction.
2232///
2233/// This routine "expands" argument packs in-place, overriding its input
2234/// parameters so that \c Args[ArgIdx] will be the available template argument.
2235///
2236/// \returns true if there is another template argument (which will be at
2237/// \c Args[ArgIdx]), false otherwise.
2238static bool hasTemplateArgumentForDeduction(ArrayRef<TemplateArgument> &Args,
2239 unsigned &ArgIdx) {
2240 if (ArgIdx == Args.size())
2241 return false;
2242
2243 const TemplateArgument &Arg = Args[ArgIdx];
2244 if (Arg.getKind() != TemplateArgument::Pack)
2245 return true;
2246
2247 assert(ArgIdx == Args.size() - 1 && "Pack not at the end of argument list?")((ArgIdx == Args.size() - 1 && "Pack not at the end of argument list?"
) ? static_cast<void> (0) : __assert_fail ("ArgIdx == Args.size() - 1 && \"Pack not at the end of argument list?\""
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 2247, __PRETTY_FUNCTION__))
;
2248 Args = Arg.pack_elements();
2249 ArgIdx = 0;
2250 return ArgIdx < Args.size();
2251}
2252
2253/// Determine whether the given set of template arguments has a pack
2254/// expansion that is not the last template argument.
2255static bool hasPackExpansionBeforeEnd(ArrayRef<TemplateArgument> Args) {
2256 bool FoundPackExpansion = false;
2257 for (const auto &A : Args) {
2258 if (FoundPackExpansion)
2259 return true;
2260
2261 if (A.getKind() == TemplateArgument::Pack)
2262 return hasPackExpansionBeforeEnd(A.pack_elements());
2263
2264 // FIXME: If this is a fixed-arity pack expansion from an outer level of
2265 // templates, it should not be treated as a pack expansion.
2266 if (A.isPackExpansion())
2267 FoundPackExpansion = true;
2268 }
2269
2270 return false;
2271}
2272
2273static Sema::TemplateDeductionResult
2274DeduceTemplateArguments(Sema &S, TemplateParameterList *TemplateParams,
2275 ArrayRef<TemplateArgument> Params,
2276 ArrayRef<TemplateArgument> Args,
2277 TemplateDeductionInfo &Info,
2278 SmallVectorImpl<DeducedTemplateArgument> &Deduced,
2279 bool NumberOfArgumentsMustMatch) {
2280 // C++0x [temp.deduct.type]p9:
2281 // If the template argument list of P contains a pack expansion that is not
2282 // the last template argument, the entire template argument list is a
2283 // non-deduced context.
2284 if (hasPackExpansionBeforeEnd(Params))
2285 return Sema::TDK_Success;
2286
2287 // C++0x [temp.deduct.type]p9:
2288 // If P has a form that contains <T> or <i>, then each argument Pi of the
2289 // respective template argument list P is compared with the corresponding
2290 // argument Ai of the corresponding template argument list of A.
2291 unsigned ArgIdx = 0, ParamIdx = 0;
2292 for (; hasTemplateArgumentForDeduction(Params, ParamIdx); ++ParamIdx) {
2293 if (!Params[ParamIdx].isPackExpansion()) {
2294 // The simple case: deduce template arguments by matching Pi and Ai.
2295
2296 // Check whether we have enough arguments.
2297 if (!hasTemplateArgumentForDeduction(Args, ArgIdx))
2298 return NumberOfArgumentsMustMatch
2299 ? Sema::TDK_MiscellaneousDeductionFailure
2300 : Sema::TDK_Success;
2301
2302 // C++1z [temp.deduct.type]p9:
2303 // During partial ordering, if Ai was originally a pack expansion [and]
2304 // Pi is not a pack expansion, template argument deduction fails.
2305 if (Args[ArgIdx].isPackExpansion())
2306 return Sema::TDK_MiscellaneousDeductionFailure;
2307
2308 // Perform deduction for this Pi/Ai pair.
2309 if (Sema::TemplateDeductionResult Result
2310 = DeduceTemplateArguments(S, TemplateParams,
2311 Params[ParamIdx], Args[ArgIdx],
2312 Info, Deduced))
2313 return Result;
2314
2315 // Move to the next argument.
2316 ++ArgIdx;
2317 continue;
2318 }
2319
2320 // The parameter is a pack expansion.
2321
2322 // C++0x [temp.deduct.type]p9:
2323 // If Pi is a pack expansion, then the pattern of Pi is compared with
2324 // each remaining argument in the template argument list of A. Each
2325 // comparison deduces template arguments for subsequent positions in the
2326 // template parameter packs expanded by Pi.
2327 TemplateArgument Pattern = Params[ParamIdx].getPackExpansionPattern();
2328
2329 // Prepare to deduce the packs within the pattern.
2330 PackDeductionScope PackScope(S, TemplateParams, Deduced, Info, Pattern);
2331
2332 // Keep track of the deduced template arguments for each parameter pack
2333 // expanded by this pack expansion (the outer index) and for each
2334 // template argument (the inner SmallVectors).
2335 for (; hasTemplateArgumentForDeduction(Args, ArgIdx) &&
2336 PackScope.hasNextElement();
2337 ++ArgIdx) {
2338 // Deduce template arguments from the pattern.
2339 if (Sema::TemplateDeductionResult Result
2340 = DeduceTemplateArguments(S, TemplateParams, Pattern, Args[ArgIdx],
2341 Info, Deduced))
2342 return Result;
2343
2344 PackScope.nextPackElement();
2345 }
2346
2347 // Build argument packs for each of the parameter packs expanded by this
2348 // pack expansion.
2349 if (auto Result = PackScope.finish())
2350 return Result;
2351 }
2352
2353 return Sema::TDK_Success;
2354}
2355
2356static Sema::TemplateDeductionResult
2357DeduceTemplateArguments(Sema &S,
2358 TemplateParameterList *TemplateParams,
2359 const TemplateArgumentList &ParamList,
2360 const TemplateArgumentList &ArgList,
2361 TemplateDeductionInfo &Info,
2362 SmallVectorImpl<DeducedTemplateArgument> &Deduced) {
2363 return DeduceTemplateArguments(S, TemplateParams, ParamList.asArray(),
2364 ArgList.asArray(), Info, Deduced,
2365 /*NumberOfArgumentsMustMatch*/false);
2366}
2367
2368/// Determine whether two template arguments are the same.
2369static bool isSameTemplateArg(ASTContext &Context,
2370 TemplateArgument X,
2371 const TemplateArgument &Y,
2372 bool PackExpansionMatchesPack = false) {
2373 // If we're checking deduced arguments (X) against original arguments (Y),
2374 // we will have flattened packs to non-expansions in X.
2375 if (PackExpansionMatchesPack && X.isPackExpansion() && !Y.isPackExpansion())
2376 X = X.getPackExpansionPattern();
2377
2378 if (X.getKind() != Y.getKind())
2379 return false;
2380
2381 switch (X.getKind()) {
2382 case TemplateArgument::Null:
2383 llvm_unreachable("Comparing NULL template argument")::llvm::llvm_unreachable_internal("Comparing NULL template argument"
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 2383)
;
2384
2385 case TemplateArgument::Type:
2386 return Context.getCanonicalType(X.getAsType()) ==
2387 Context.getCanonicalType(Y.getAsType());
2388
2389 case TemplateArgument::Declaration:
2390 return isSameDeclaration(X.getAsDecl(), Y.getAsDecl());
2391
2392 case TemplateArgument::NullPtr:
2393 return Context.hasSameType(X.getNullPtrType(), Y.getNullPtrType());
2394
2395 case TemplateArgument::Template:
2396 case TemplateArgument::TemplateExpansion:
2397 return Context.getCanonicalTemplateName(
2398 X.getAsTemplateOrTemplatePattern()).getAsVoidPointer() ==
2399 Context.getCanonicalTemplateName(
2400 Y.getAsTemplateOrTemplatePattern()).getAsVoidPointer();
2401
2402 case TemplateArgument::Integral:
2403 return hasSameExtendedValue(X.getAsIntegral(), Y.getAsIntegral());
2404
2405 case TemplateArgument::Expression: {
2406 llvm::FoldingSetNodeID XID, YID;
2407 X.getAsExpr()->Profile(XID, Context, true);
2408 Y.getAsExpr()->Profile(YID, Context, true);
2409 return XID == YID;
2410 }
2411
2412 case TemplateArgument::Pack:
2413 if (X.pack_size() != Y.pack_size())
2414 return false;
2415
2416 for (TemplateArgument::pack_iterator XP = X.pack_begin(),
2417 XPEnd = X.pack_end(),
2418 YP = Y.pack_begin();
2419 XP != XPEnd; ++XP, ++YP)
2420 if (!isSameTemplateArg(Context, *XP, *YP, PackExpansionMatchesPack))
2421 return false;
2422
2423 return true;
2424 }
2425
2426 llvm_unreachable("Invalid TemplateArgument Kind!")::llvm::llvm_unreachable_internal("Invalid TemplateArgument Kind!"
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 2426)
;
2427}
2428
2429/// Allocate a TemplateArgumentLoc where all locations have
2430/// been initialized to the given location.
2431///
2432/// \param Arg The template argument we are producing template argument
2433/// location information for.
2434///
2435/// \param NTTPType For a declaration template argument, the type of
2436/// the non-type template parameter that corresponds to this template
2437/// argument. Can be null if no type sugar is available to add to the
2438/// type from the template argument.
2439///
2440/// \param Loc The source location to use for the resulting template
2441/// argument.
2442TemplateArgumentLoc
2443Sema::getTrivialTemplateArgumentLoc(const TemplateArgument &Arg,
2444 QualType NTTPType, SourceLocation Loc) {
2445 switch (Arg.getKind()) {
2446 case TemplateArgument::Null:
2447 llvm_unreachable("Can't get a NULL template argument here")::llvm::llvm_unreachable_internal("Can't get a NULL template argument here"
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 2447)
;
2448
2449 case TemplateArgument::Type:
2450 return TemplateArgumentLoc(
2451 Arg, Context.getTrivialTypeSourceInfo(Arg.getAsType(), Loc));
2452
2453 case TemplateArgument::Declaration: {
2454 if (NTTPType.isNull())
2455 NTTPType = Arg.getParamTypeForDecl();
2456 Expr *E = BuildExpressionFromDeclTemplateArgument(Arg, NTTPType, Loc)
2457 .getAs<Expr>();
2458 return TemplateArgumentLoc(TemplateArgument(E), E);
2459 }
2460
2461 case TemplateArgument::NullPtr: {
2462 if (NTTPType.isNull())
2463 NTTPType = Arg.getNullPtrType();
2464 Expr *E = BuildExpressionFromDeclTemplateArgument(Arg, NTTPType, Loc)
2465 .getAs<Expr>();
2466 return TemplateArgumentLoc(TemplateArgument(NTTPType, /*isNullPtr*/true),
2467 E);
2468 }
2469
2470 case TemplateArgument::Integral: {
2471 Expr *E =
2472 BuildExpressionFromIntegralTemplateArgument(Arg, Loc).getAs<Expr>();
2473 return TemplateArgumentLoc(TemplateArgument(E), E);
2474 }
2475
2476 case TemplateArgument::Template:
2477 case TemplateArgument::TemplateExpansion: {
2478 NestedNameSpecifierLocBuilder Builder;
2479 TemplateName Template = Arg.getAsTemplate();
2480 if (DependentTemplateName *DTN = Template.getAsDependentTemplateName())
2481 Builder.MakeTrivial(Context, DTN->getQualifier(), Loc);
2482 else if (QualifiedTemplateName *QTN =
2483 Template.getAsQualifiedTemplateName())
2484 Builder.MakeTrivial(Context, QTN->getQualifier(), Loc);
2485
2486 if (Arg.getKind() == TemplateArgument::Template)
2487 return TemplateArgumentLoc(Arg, Builder.getWithLocInContext(Context),
2488 Loc);
2489
2490 return TemplateArgumentLoc(Arg, Builder.getWithLocInContext(Context),
2491 Loc, Loc);
2492 }
2493
2494 case TemplateArgument::Expression:
2495 return TemplateArgumentLoc(Arg, Arg.getAsExpr());
2496
2497 case TemplateArgument::Pack:
2498 return TemplateArgumentLoc(Arg, TemplateArgumentLocInfo());
2499 }
2500
2501 llvm_unreachable("Invalid TemplateArgument Kind!")::llvm::llvm_unreachable_internal("Invalid TemplateArgument Kind!"
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 2501)
;
2502}
2503
2504/// Convert the given deduced template argument and add it to the set of
2505/// fully-converted template arguments.
2506static bool
2507ConvertDeducedTemplateArgument(Sema &S, NamedDecl *Param,
2508 DeducedTemplateArgument Arg,
2509 NamedDecl *Template,
2510 TemplateDeductionInfo &Info,
2511 bool IsDeduced,
2512 SmallVectorImpl<TemplateArgument> &Output) {
2513 auto ConvertArg = [&](DeducedTemplateArgument Arg,
2514 unsigned ArgumentPackIndex) {
2515 // Convert the deduced template argument into a template
2516 // argument that we can check, almost as if the user had written
2517 // the template argument explicitly.
2518 TemplateArgumentLoc ArgLoc =
2519 S.getTrivialTemplateArgumentLoc(Arg, QualType(), Info.getLocation());
2520
2521 // Check the template argument, converting it as necessary.
2522 return S.CheckTemplateArgument(
2523 Param, ArgLoc, Template, Template->getLocation(),
2524 Template->getSourceRange().getEnd(), ArgumentPackIndex, Output,
2525 IsDeduced
2526 ? (Arg.wasDeducedFromArrayBound() ? Sema::CTAK_DeducedFromArrayBound
2527 : Sema::CTAK_Deduced)
2528 : Sema::CTAK_Specified);
2529 };
2530
2531 if (Arg.getKind() == TemplateArgument::Pack) {
2532 // This is a template argument pack, so check each of its arguments against
2533 // the template parameter.
2534 SmallVector<TemplateArgument, 2> PackedArgsBuilder;
2535 for (const auto &P : Arg.pack_elements()) {
2536 // When converting the deduced template argument, append it to the
2537 // general output list. We need to do this so that the template argument
2538 // checking logic has all of the prior template arguments available.
2539 DeducedTemplateArgument InnerArg(P);
2540 InnerArg.setDeducedFromArrayBound(Arg.wasDeducedFromArrayBound());
2541 assert(InnerArg.getKind() != TemplateArgument::Pack &&((InnerArg.getKind() != TemplateArgument::Pack && "deduced nested pack"
) ? static_cast<void> (0) : __assert_fail ("InnerArg.getKind() != TemplateArgument::Pack && \"deduced nested pack\""
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 2542, __PRETTY_FUNCTION__))
2542 "deduced nested pack")((InnerArg.getKind() != TemplateArgument::Pack && "deduced nested pack"
) ? static_cast<void> (0) : __assert_fail ("InnerArg.getKind() != TemplateArgument::Pack && \"deduced nested pack\""
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 2542, __PRETTY_FUNCTION__))
;
2543 if (P.isNull()) {
2544 // We deduced arguments for some elements of this pack, but not for
2545 // all of them. This happens if we get a conditionally-non-deduced
2546 // context in a pack expansion (such as an overload set in one of the
2547 // arguments).
2548 S.Diag(Param->getLocation(),
2549 diag::err_template_arg_deduced_incomplete_pack)
2550 << Arg << Param;
2551 return true;
2552 }
2553 if (ConvertArg(InnerArg, PackedArgsBuilder.size()))
2554 return true;
2555
2556 // Move the converted template argument into our argument pack.
2557 PackedArgsBuilder.push_back(Output.pop_back_val());
2558 }
2559
2560 // If the pack is empty, we still need to substitute into the parameter
2561 // itself, in case that substitution fails.
2562 if (PackedArgsBuilder.empty()) {
2563 LocalInstantiationScope Scope(S);
2564 TemplateArgumentList TemplateArgs(TemplateArgumentList::OnStack, Output);
2565 MultiLevelTemplateArgumentList Args(TemplateArgs);
2566
2567 if (auto *NTTP = dyn_cast<NonTypeTemplateParmDecl>(Param)) {
2568 Sema::InstantiatingTemplate Inst(S, Template->getLocation(), Template,
2569 NTTP, Output,
2570 Template->getSourceRange());
2571 if (Inst.isInvalid() ||
2572 S.SubstType(NTTP->getType(), Args, NTTP->getLocation(),
2573 NTTP->getDeclName()).isNull())
2574 return true;
2575 } else if (auto *TTP = dyn_cast<TemplateTemplateParmDecl>(Param)) {
2576 Sema::InstantiatingTemplate Inst(S, Template->getLocation(), Template,
2577 TTP, Output,
2578 Template->getSourceRange());
2579 if (Inst.isInvalid() || !S.SubstDecl(TTP, S.CurContext, Args))
2580 return true;
2581 }
2582 // For type parameters, no substitution is ever required.
2583 }
2584
2585 // Create the resulting argument pack.
2586 Output.push_back(
2587 TemplateArgument::CreatePackCopy(S.Context, PackedArgsBuilder));
2588 return false;
2589 }
2590
2591 return ConvertArg(Arg, 0);
2592}
2593
2594// FIXME: This should not be a template, but
2595// ClassTemplatePartialSpecializationDecl sadly does not derive from
2596// TemplateDecl.
2597template<typename TemplateDeclT>
2598static Sema::TemplateDeductionResult ConvertDeducedTemplateArguments(
2599 Sema &S, TemplateDeclT *Template, bool IsDeduced,
2600 SmallVectorImpl<DeducedTemplateArgument> &Deduced,
2601 TemplateDeductionInfo &Info, SmallVectorImpl<TemplateArgument> &Builder,
2602 LocalInstantiationScope *CurrentInstantiationScope = nullptr,
2603 unsigned NumAlreadyConverted = 0, bool PartialOverloading = false) {
2604 TemplateParameterList *TemplateParams = Template->getTemplateParameters();
2605
2606 for (unsigned I = 0, N = TemplateParams->size(); I != N; ++I) {
2607 NamedDecl *Param = TemplateParams->getParam(I);
2608
2609 // C++0x [temp.arg.explicit]p3:
2610 // A trailing template parameter pack (14.5.3) not otherwise deduced will
2611 // be deduced to an empty sequence of template arguments.
2612 // FIXME: Where did the word "trailing" come from?
2613 if (Deduced[I].isNull() && Param->isTemplateParameterPack()) {
2614 if (auto Result = PackDeductionScope(S, TemplateParams, Deduced, Info, I)
2615 .finish(/*TreatNoDeductionsAsNonDeduced*/false))
2616 return Result;
2617 }
2618
2619 if (!Deduced[I].isNull()) {
2620 if (I < NumAlreadyConverted) {
2621 // We may have had explicitly-specified template arguments for a
2622 // template parameter pack (that may or may not have been extended
2623 // via additional deduced arguments).
2624 if (Param->isParameterPack() && CurrentInstantiationScope &&
2625 CurrentInstantiationScope->getPartiallySubstitutedPack() == Param) {
2626 // Forget the partially-substituted pack; its substitution is now
2627 // complete.
2628 CurrentInstantiationScope->ResetPartiallySubstitutedPack();
2629 // We still need to check the argument in case it was extended by
2630 // deduction.
2631 } else {
2632 // We have already fully type-checked and converted this
2633 // argument, because it was explicitly-specified. Just record the
2634 // presence of this argument.
2635 Builder.push_back(Deduced[I]);
2636 continue;
2637 }
2638 }
2639
2640 // We may have deduced this argument, so it still needs to be
2641 // checked and converted.
2642 if (ConvertDeducedTemplateArgument(S, Param, Deduced[I], Template, Info,
2643 IsDeduced, Builder)) {
2644 Info.Param = makeTemplateParameter(Param);
2645 // FIXME: These template arguments are temporary. Free them!
2646 Info.reset(TemplateArgumentList::CreateCopy(S.Context, Builder));
2647 return Sema::TDK_SubstitutionFailure;
2648 }
2649
2650 continue;
2651 }
2652
2653 // Substitute into the default template argument, if available.
2654 bool HasDefaultArg = false;
2655 TemplateDecl *TD = dyn_cast<TemplateDecl>(Template);
2656 if (!TD) {
2657 assert(isa<ClassTemplatePartialSpecializationDecl>(Template) ||((isa<ClassTemplatePartialSpecializationDecl>(Template)
|| isa<VarTemplatePartialSpecializationDecl>(Template)
) ? static_cast<void> (0) : __assert_fail ("isa<ClassTemplatePartialSpecializationDecl>(Template) || isa<VarTemplatePartialSpecializationDecl>(Template)"
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 2658, __PRETTY_FUNCTION__))
2658 isa<VarTemplatePartialSpecializationDecl>(Template))((isa<ClassTemplatePartialSpecializationDecl>(Template)
|| isa<VarTemplatePartialSpecializationDecl>(Template)
) ? static_cast<void> (0) : __assert_fail ("isa<ClassTemplatePartialSpecializationDecl>(Template) || isa<VarTemplatePartialSpecializationDecl>(Template)"
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 2658, __PRETTY_FUNCTION__))
;
2659 return Sema::TDK_Incomplete;
2660 }
2661
2662 TemplateArgumentLoc DefArg = S.SubstDefaultTemplateArgumentIfAvailable(
2663 TD, TD->getLocation(), TD->getSourceRange().getEnd(), Param, Builder,
2664 HasDefaultArg);
2665
2666 // If there was no default argument, deduction is incomplete.
2667 if (DefArg.getArgument().isNull()) {
2668 Info.Param = makeTemplateParameter(
2669 const_cast<NamedDecl *>(TemplateParams->getParam(I)));
2670 Info.reset(TemplateArgumentList::CreateCopy(S.Context, Builder));
2671 if (PartialOverloading) break;
2672
2673 return HasDefaultArg ? Sema::TDK_SubstitutionFailure
2674 : Sema::TDK_Incomplete;
2675 }
2676
2677 // Check whether we can actually use the default argument.
2678 if (S.CheckTemplateArgument(Param, DefArg, TD, TD->getLocation(),
2679 TD->getSourceRange().getEnd(), 0, Builder,
2680 Sema::CTAK_Specified)) {
2681 Info.Param = makeTemplateParameter(
2682 const_cast<NamedDecl *>(TemplateParams->getParam(I)));
2683 // FIXME: These template arguments are temporary. Free them!
2684 Info.reset(TemplateArgumentList::CreateCopy(S.Context, Builder));
2685 return Sema::TDK_SubstitutionFailure;
2686 }
2687
2688 // If we get here, we successfully used the default template argument.
2689 }
2690
2691 return Sema::TDK_Success;
2692}
2693
2694static DeclContext *getAsDeclContextOrEnclosing(Decl *D) {
2695 if (auto *DC = dyn_cast<DeclContext>(D))
2696 return DC;
2697 return D->getDeclContext();
2698}
2699
2700template<typename T> struct IsPartialSpecialization {
2701 static constexpr bool value = false;
2702};
2703template<>
2704struct IsPartialSpecialization<ClassTemplatePartialSpecializationDecl> {
2705 static constexpr bool value = true;
2706};
2707template<>
2708struct IsPartialSpecialization<VarTemplatePartialSpecializationDecl> {
2709 static constexpr bool value = true;
2710};
2711
2712/// Complete template argument deduction for a partial specialization.
2713template <typename T>
2714static typename std::enable_if<IsPartialSpecialization<T>::value,
2715 Sema::TemplateDeductionResult>::type
2716FinishTemplateArgumentDeduction(
2717 Sema &S, T *Partial, bool IsPartialOrdering,
2718 const TemplateArgumentList &TemplateArgs,
2719 SmallVectorImpl<DeducedTemplateArgument> &Deduced,
2720 TemplateDeductionInfo &Info) {
2721 // Unevaluated SFINAE context.
2722 EnterExpressionEvaluationContext Unevaluated(
2723 S, Sema::ExpressionEvaluationContext::Unevaluated);
2724 Sema::SFINAETrap Trap(S);
2725
2726 Sema::ContextRAII SavedContext(S, getAsDeclContextOrEnclosing(Partial));
2727
2728 // C++ [temp.deduct.type]p2:
2729 // [...] or if any template argument remains neither deduced nor
2730 // explicitly specified, template argument deduction fails.
2731 SmallVector<TemplateArgument, 4> Builder;
2732 if (auto Result = ConvertDeducedTemplateArguments(
2733 S, Partial, IsPartialOrdering, Deduced, Info, Builder))
2734 return Result;
2735
2736 // Form the template argument list from the deduced template arguments.
2737 TemplateArgumentList *DeducedArgumentList
2738 = TemplateArgumentList::CreateCopy(S.Context, Builder);
2739
2740 Info.reset(DeducedArgumentList);
2741
2742 // Substitute the deduced template arguments into the template
2743 // arguments of the class template partial specialization, and
2744 // verify that the instantiated template arguments are both valid
2745 // and are equivalent to the template arguments originally provided
2746 // to the class template.
2747 LocalInstantiationScope InstScope(S);
2748 auto *Template = Partial->getSpecializedTemplate();
2749 const ASTTemplateArgumentListInfo *PartialTemplArgInfo =
2750 Partial->getTemplateArgsAsWritten();
2751 const TemplateArgumentLoc *PartialTemplateArgs =
2752 PartialTemplArgInfo->getTemplateArgs();
2753
2754 TemplateArgumentListInfo InstArgs(PartialTemplArgInfo->LAngleLoc,
2755 PartialTemplArgInfo->RAngleLoc);
2756
2757 if (S.Subst(PartialTemplateArgs, PartialTemplArgInfo->NumTemplateArgs,
2758 InstArgs, MultiLevelTemplateArgumentList(*DeducedArgumentList))) {
2759 unsigned ArgIdx = InstArgs.size(), ParamIdx = ArgIdx;
2760 if (ParamIdx >= Partial->getTemplateParameters()->size())
2761 ParamIdx = Partial->getTemplateParameters()->size() - 1;
2762
2763 Decl *Param = const_cast<NamedDecl *>(
2764 Partial->getTemplateParameters()->getParam(ParamIdx));
2765 Info.Param = makeTemplateParameter(Param);
2766 Info.FirstArg = PartialTemplateArgs[ArgIdx].getArgument();
2767 return Sema::TDK_SubstitutionFailure;
2768 }
2769
2770 SmallVector<TemplateArgument, 4> ConvertedInstArgs;
2771 if (S.CheckTemplateArgumentList(Template, Partial->getLocation(), InstArgs,
2772 false, ConvertedInstArgs))
2773 return Sema::TDK_SubstitutionFailure;
2774
2775 TemplateParameterList *TemplateParams = Template->getTemplateParameters();
2776 for (unsigned I = 0, E = TemplateParams->size(); I != E; ++I) {
2777 TemplateArgument InstArg = ConvertedInstArgs.data()[I];
2778 if (!isSameTemplateArg(S.Context, TemplateArgs[I], InstArg)) {
2779 Info.Param = makeTemplateParameter(TemplateParams->getParam(I));
2780 Info.FirstArg = TemplateArgs[I];
2781 Info.SecondArg = InstArg;
2782 return Sema::TDK_NonDeducedMismatch;
2783 }
2784 }
2785
2786 if (Trap.hasErrorOccurred())
2787 return Sema::TDK_SubstitutionFailure;
2788
2789 return Sema::TDK_Success;
2790}
2791
2792/// Complete template argument deduction for a class or variable template,
2793/// when partial ordering against a partial specialization.
2794// FIXME: Factor out duplication with partial specialization version above.
2795static Sema::TemplateDeductionResult FinishTemplateArgumentDeduction(
2796 Sema &S, TemplateDecl *Template, bool PartialOrdering,
2797 const TemplateArgumentList &TemplateArgs,
2798 SmallVectorImpl<DeducedTemplateArgument> &Deduced,
2799 TemplateDeductionInfo &Info) {
2800 // Unevaluated SFINAE context.
2801 EnterExpressionEvaluationContext Unevaluated(
2802 S, Sema::ExpressionEvaluationContext::Unevaluated);
2803 Sema::SFINAETrap Trap(S);
2804
2805 Sema::ContextRAII SavedContext(S, getAsDeclContextOrEnclosing(Template));
2806
2807 // C++ [temp.deduct.type]p2:
2808 // [...] or if any template argument remains neither deduced nor
2809 // explicitly specified, template argument deduction fails.
2810 SmallVector<TemplateArgument, 4> Builder;
2811 if (auto Result = ConvertDeducedTemplateArguments(
2812 S, Template, /*IsDeduced*/PartialOrdering, Deduced, Info, Builder))
2813 return Result;
2814
2815 // Check that we produced the correct argument list.
2816 TemplateParameterList *TemplateParams = Template->getTemplateParameters();
2817 for (unsigned I = 0, E = TemplateParams->size(); I != E; ++I) {
2818 TemplateArgument InstArg = Builder[I];
2819 if (!isSameTemplateArg(S.Context, TemplateArgs[I], InstArg,
2820 /*PackExpansionMatchesPack*/true)) {
2821 Info.Param = makeTemplateParameter(TemplateParams->getParam(I));
2822 Info.FirstArg = TemplateArgs[I];
2823 Info.SecondArg = InstArg;
2824 return Sema::TDK_NonDeducedMismatch;
2825 }
2826 }
2827
2828 if (Trap.hasErrorOccurred())
2829 return Sema::TDK_SubstitutionFailure;
2830
2831 return Sema::TDK_Success;
2832}
2833
2834
2835/// Perform template argument deduction to determine whether
2836/// the given template arguments match the given class template
2837/// partial specialization per C++ [temp.class.spec.match].
2838Sema::TemplateDeductionResult
2839Sema::DeduceTemplateArguments(ClassTemplatePartialSpecializationDecl *Partial,
2840 const TemplateArgumentList &TemplateArgs,
2841 TemplateDeductionInfo &Info) {
2842 if (Partial->isInvalidDecl())
2843 return TDK_Invalid;
2844
2845 // C++ [temp.class.spec.match]p2:
2846 // A partial specialization matches a given actual template
2847 // argument list if the template arguments of the partial
2848 // specialization can be deduced from the actual template argument
2849 // list (14.8.2).
2850
2851 // Unevaluated SFINAE context.
2852 EnterExpressionEvaluationContext Unevaluated(
2853 *this, Sema::ExpressionEvaluationContext::Unevaluated);
2854 SFINAETrap Trap(*this);
2855
2856 SmallVector<DeducedTemplateArgument, 4> Deduced;
2857 Deduced.resize(Partial->getTemplateParameters()->size());
2858 if (TemplateDeductionResult Result
2859 = ::DeduceTemplateArguments(*this,
2860 Partial->getTemplateParameters(),
2861 Partial->getTemplateArgs(),
2862 TemplateArgs, Info, Deduced))
2863 return Result;
2864
2865 SmallVector<TemplateArgument, 4> DeducedArgs(Deduced.begin(), Deduced.end());
2866 InstantiatingTemplate Inst(*this, Info.getLocation(), Partial, DeducedArgs,
2867 Info);
2868 if (Inst.isInvalid())
2869 return TDK_InstantiationDepth;
2870
2871 if (Trap.hasErrorOccurred())
2872 return Sema::TDK_SubstitutionFailure;
2873
2874 return ::FinishTemplateArgumentDeduction(
2875 *this, Partial, /*PartialOrdering=*/false, TemplateArgs, Deduced, Info);
2876}
2877
2878/// Perform template argument deduction to determine whether
2879/// the given template arguments match the given variable template
2880/// partial specialization per C++ [temp.class.spec.match].
2881Sema::TemplateDeductionResult
2882Sema::DeduceTemplateArguments(VarTemplatePartialSpecializationDecl *Partial,
2883 const TemplateArgumentList &TemplateArgs,
2884 TemplateDeductionInfo &Info) {
2885 if (Partial->isInvalidDecl())
2886 return TDK_Invalid;
2887
2888 // C++ [temp.class.spec.match]p2:
2889 // A partial specialization matches a given actual template
2890 // argument list if the template arguments of the partial
2891 // specialization can be deduced from the actual template argument
2892 // list (14.8.2).
2893
2894 // Unevaluated SFINAE context.
2895 EnterExpressionEvaluationContext Unevaluated(
2896 *this, Sema::ExpressionEvaluationContext::Unevaluated);
2897 SFINAETrap Trap(*this);
2898
2899 SmallVector<DeducedTemplateArgument, 4> Deduced;
2900 Deduced.resize(Partial->getTemplateParameters()->size());
2901 if (TemplateDeductionResult Result = ::DeduceTemplateArguments(
2902 *this, Partial->getTemplateParameters(), Partial->getTemplateArgs(),
2903 TemplateArgs, Info, Deduced))
2904 return Result;
2905
2906 SmallVector<TemplateArgument, 4> DeducedArgs(Deduced.begin(), Deduced.end());
2907 InstantiatingTemplate Inst(*this, Info.getLocation(), Partial, DeducedArgs,
2908 Info);
2909 if (Inst.isInvalid())
2910 return TDK_InstantiationDepth;
2911
2912 if (Trap.hasErrorOccurred())
2913 return Sema::TDK_SubstitutionFailure;
2914
2915 return ::FinishTemplateArgumentDeduction(
2916 *this, Partial, /*PartialOrdering=*/false, TemplateArgs, Deduced, Info);
2917}
2918
2919/// Determine whether the given type T is a simple-template-id type.
2920static bool isSimpleTemplateIdType(QualType T) {
2921 if (const TemplateSpecializationType *Spec
2922 = T->getAs<TemplateSpecializationType>())
2923 return Spec->getTemplateName().getAsTemplateDecl() != nullptr;
2924
2925 // C++17 [temp.local]p2:
2926 // the injected-class-name [...] is equivalent to the template-name followed
2927 // by the template-arguments of the class template specialization or partial
2928 // specialization enclosed in <>
2929 // ... which means it's equivalent to a simple-template-id.
2930 //
2931 // This only arises during class template argument deduction for a copy
2932 // deduction candidate, where it permits slicing.
2933 if (T->getAs<InjectedClassNameType>())
2934 return true;
2935
2936 return false;
2937}
2938
2939/// Substitute the explicitly-provided template arguments into the
2940/// given function template according to C++ [temp.arg.explicit].
2941///
2942/// \param FunctionTemplate the function template into which the explicit
2943/// template arguments will be substituted.
2944///
2945/// \param ExplicitTemplateArgs the explicitly-specified template
2946/// arguments.
2947///
2948/// \param Deduced the deduced template arguments, which will be populated
2949/// with the converted and checked explicit template arguments.
2950///
2951/// \param ParamTypes will be populated with the instantiated function
2952/// parameters.
2953///
2954/// \param FunctionType if non-NULL, the result type of the function template
2955/// will also be instantiated and the pointed-to value will be updated with
2956/// the instantiated function type.
2957///
2958/// \param Info if substitution fails for any reason, this object will be
2959/// populated with more information about the failure.
2960///
2961/// \returns TDK_Success if substitution was successful, or some failure
2962/// condition.
2963Sema::TemplateDeductionResult
2964Sema::SubstituteExplicitTemplateArguments(
2965 FunctionTemplateDecl *FunctionTemplate,
2966 TemplateArgumentListInfo &ExplicitTemplateArgs,
2967 SmallVectorImpl<DeducedTemplateArgument> &Deduced,
2968 SmallVectorImpl<QualType> &ParamTypes,
2969 QualType *FunctionType,
2970 TemplateDeductionInfo &Info) {
2971 FunctionDecl *Function = FunctionTemplate->getTemplatedDecl();
2972 TemplateParameterList *TemplateParams
2973 = FunctionTemplate->getTemplateParameters();
2974
2975 if (ExplicitTemplateArgs.size() == 0) {
2976 // No arguments to substitute; just copy over the parameter types and
2977 // fill in the function type.
2978 for (auto P : Function->parameters())
2979 ParamTypes.push_back(P->getType());
2980
2981 if (FunctionType)
2982 *FunctionType = Function->getType();
2983 return TDK_Success;
2984 }
2985
2986 // Unevaluated SFINAE context.
2987 EnterExpressionEvaluationContext Unevaluated(
2988 *this, Sema::ExpressionEvaluationContext::Unevaluated);
2989 SFINAETrap Trap(*this);
2990
2991 // C++ [temp.arg.explicit]p3:
2992 // Template arguments that are present shall be specified in the
2993 // declaration order of their corresponding template-parameters. The
2994 // template argument list shall not specify more template-arguments than
2995 // there are corresponding template-parameters.
2996 SmallVector<TemplateArgument, 4> Builder;
2997
2998 // Enter a new template instantiation context where we check the
2999 // explicitly-specified template arguments against this function template,
3000 // and then substitute them into the function parameter types.
3001 SmallVector<TemplateArgument, 4> DeducedArgs;
3002 InstantiatingTemplate Inst(
3003 *this, Info.getLocation(), FunctionTemplate, DeducedArgs,
3004 CodeSynthesisContext::ExplicitTemplateArgumentSubstitution, Info);
3005 if (Inst.isInvalid())
3006 return TDK_InstantiationDepth;
3007
3008 if (CheckTemplateArgumentList(FunctionTemplate, SourceLocation(),
3009 ExplicitTemplateArgs, true, Builder, false) ||
3010 Trap.hasErrorOccurred()) {
3011 unsigned Index = Builder.size();
3012 if (Index >= TemplateParams->size())
3013 return TDK_SubstitutionFailure;
3014 Info.Param = makeTemplateParameter(TemplateParams->getParam(Index));
3015 return TDK_InvalidExplicitArguments;
3016 }
3017
3018 // Form the template argument list from the explicitly-specified
3019 // template arguments.
3020 TemplateArgumentList *ExplicitArgumentList
3021 = TemplateArgumentList::CreateCopy(Context, Builder);
3022 Info.setExplicitArgs(ExplicitArgumentList);
3023
3024 // Template argument deduction and the final substitution should be
3025 // done in the context of the templated declaration. Explicit
3026 // argument substitution, on the other hand, needs to happen in the
3027 // calling context.
3028 ContextRAII SavedContext(*this, FunctionTemplate->getTemplatedDecl());
3029
3030 // If we deduced template arguments for a template parameter pack,
3031 // note that the template argument pack is partially substituted and record
3032 // the explicit template arguments. They'll be used as part of deduction
3033 // for this template parameter pack.
3034 unsigned PartiallySubstitutedPackIndex = -1u;
3035 if (!Builder.empty()) {
3036 const TemplateArgument &Arg = Builder.back();
3037 if (Arg.getKind() == TemplateArgument::Pack) {
3038 auto *Param = TemplateParams->getParam(Builder.size() - 1);
3039 // If this is a fully-saturated fixed-size pack, it should be
3040 // fully-substituted, not partially-substituted.
3041 Optional<unsigned> Expansions = getExpandedPackSize(Param);
3042 if (!Expansions || Arg.pack_size() < *Expansions) {
3043 PartiallySubstitutedPackIndex = Builder.size() - 1;
3044 CurrentInstantiationScope->SetPartiallySubstitutedPack(
3045 Param, Arg.pack_begin(), Arg.pack_size());
3046 }
3047 }
3048 }
3049
3050 const FunctionProtoType *Proto
3051 = Function->getType()->getAs<FunctionProtoType>();
3052 assert(Proto && "Function template does not have a prototype?")((Proto && "Function template does not have a prototype?"
) ? static_cast<void> (0) : __assert_fail ("Proto && \"Function template does not have a prototype?\""
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 3052, __PRETTY_FUNCTION__))
;
3053
3054 // Isolate our substituted parameters from our caller.
3055 LocalInstantiationScope InstScope(*this, /*MergeWithOuterScope*/true);
3056
3057 ExtParameterInfoBuilder ExtParamInfos;
3058
3059 // Instantiate the types of each of the function parameters given the
3060 // explicitly-specified template arguments. If the function has a trailing
3061 // return type, substitute it after the arguments to ensure we substitute
3062 // in lexical order.
3063 if (Proto->hasTrailingReturn()) {
3064 if (SubstParmTypes(Function->getLocation(), Function->parameters(),
3065 Proto->getExtParameterInfosOrNull(),
3066 MultiLevelTemplateArgumentList(*ExplicitArgumentList),
3067 ParamTypes, /*params*/ nullptr, ExtParamInfos))
3068 return TDK_SubstitutionFailure;
3069 }
3070
3071 // Instantiate the return type.
3072 QualType ResultType;
3073 {
3074 // C++11 [expr.prim.general]p3:
3075 // If a declaration declares a member function or member function
3076 // template of a class X, the expression this is a prvalue of type
3077 // "pointer to cv-qualifier-seq X" between the optional cv-qualifer-seq
3078 // and the end of the function-definition, member-declarator, or
3079 // declarator.
3080 Qualifiers ThisTypeQuals;
3081 CXXRecordDecl *ThisContext = nullptr;
3082 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Function)) {
3083 ThisContext = Method->getParent();
3084 ThisTypeQuals = Method->getMethodQualifiers();
3085 }
3086
3087 CXXThisScopeRAII ThisScope(*this, ThisContext, ThisTypeQuals,
3088 getLangOpts().CPlusPlus11);
3089
3090 ResultType =
3091 SubstType(Proto->getReturnType(),
3092 MultiLevelTemplateArgumentList(*ExplicitArgumentList),
3093 Function->getTypeSpecStartLoc(), Function->getDeclName());
3094 if (ResultType.isNull() || Trap.hasErrorOccurred())
3095 return TDK_SubstitutionFailure;
3096 }
3097
3098 // Instantiate the types of each of the function parameters given the
3099 // explicitly-specified template arguments if we didn't do so earlier.
3100 if (!Proto->hasTrailingReturn() &&
3101 SubstParmTypes(Function->getLocation(), Function->parameters(),
3102 Proto->getExtParameterInfosOrNull(),
3103 MultiLevelTemplateArgumentList(*ExplicitArgumentList),
3104 ParamTypes, /*params*/ nullptr, ExtParamInfos))
3105 return TDK_SubstitutionFailure;
3106
3107 if (FunctionType) {
3108 auto EPI = Proto->getExtProtoInfo();
3109 EPI.ExtParameterInfos = ExtParamInfos.getPointerOrNull(ParamTypes.size());
3110
3111 // In C++1z onwards, exception specifications are part of the function type,
3112 // so substitution into the type must also substitute into the exception
3113 // specification.
3114 SmallVector<QualType, 4> ExceptionStorage;
3115 if (getLangOpts().CPlusPlus17 &&
3116 SubstExceptionSpec(
3117 Function->getLocation(), EPI.ExceptionSpec, ExceptionStorage,
3118 MultiLevelTemplateArgumentList(*ExplicitArgumentList)))
3119 return TDK_SubstitutionFailure;
3120
3121 *FunctionType = BuildFunctionType(ResultType, ParamTypes,
3122 Function->getLocation(),
3123 Function->getDeclName(),
3124 EPI);
3125 if (FunctionType->isNull() || Trap.hasErrorOccurred())
3126 return TDK_SubstitutionFailure;
3127 }
3128
3129 // C++ [temp.arg.explicit]p2:
3130 // Trailing template arguments that can be deduced (14.8.2) may be
3131 // omitted from the list of explicit template-arguments. If all of the
3132 // template arguments can be deduced, they may all be omitted; in this
3133 // case, the empty template argument list <> itself may also be omitted.
3134 //
3135 // Take all of the explicitly-specified arguments and put them into
3136 // the set of deduced template arguments. The partially-substituted
3137 // parameter pack, however, will be set to NULL since the deduction
3138 // mechanism handles the partially-substituted argument pack directly.
3139 Deduced.reserve(TemplateParams->size());
3140 for (unsigned I = 0, N = ExplicitArgumentList->size(); I != N; ++I) {
3141 const TemplateArgument &Arg = ExplicitArgumentList->get(I);
3142 if (I == PartiallySubstitutedPackIndex)
3143 Deduced.push_back(DeducedTemplateArgument());
3144 else
3145 Deduced.push_back(Arg);
3146 }
3147
3148 return TDK_Success;
3149}
3150
3151/// Check whether the deduced argument type for a call to a function
3152/// template matches the actual argument type per C++ [temp.deduct.call]p4.
3153static Sema::TemplateDeductionResult
3154CheckOriginalCallArgDeduction(Sema &S, TemplateDeductionInfo &Info,
3155 Sema::OriginalCallArg OriginalArg,
3156 QualType DeducedA) {
3157 ASTContext &Context = S.Context;
3158
3159 auto Failed = [&]() -> Sema::TemplateDeductionResult {
3160 Info.FirstArg = TemplateArgument(DeducedA);
3161 Info.SecondArg = TemplateArgument(OriginalArg.OriginalArgType);
3162 Info.CallArgIndex = OriginalArg.ArgIdx;
3163 return OriginalArg.DecomposedParam ? Sema::TDK_DeducedMismatchNested
3164 : Sema::TDK_DeducedMismatch;
3165 };
3166
3167 QualType A = OriginalArg.OriginalArgType;
3168 QualType OriginalParamType = OriginalArg.OriginalParamType;
3169
3170 // Check for type equality (top-level cv-qualifiers are ignored).
3171 if (Context.hasSameUnqualifiedType(A, DeducedA))
3172 return Sema::TDK_Success;
3173
3174 // Strip off references on the argument types; they aren't needed for
3175 // the following checks.
3176 if (const ReferenceType *DeducedARef = DeducedA->getAs<ReferenceType>())
3177 DeducedA = DeducedARef->getPointeeType();
3178 if (const ReferenceType *ARef = A->getAs<ReferenceType>())
3179 A = ARef->getPointeeType();
3180
3181 // C++ [temp.deduct.call]p4:
3182 // [...] However, there are three cases that allow a difference:
3183 // - If the original P is a reference type, the deduced A (i.e., the
3184 // type referred to by the reference) can be more cv-qualified than
3185 // the transformed A.
3186 if (const ReferenceType *OriginalParamRef
3187 = OriginalParamType->getAs<ReferenceType>()) {
3188 // We don't want to keep the reference around any more.
3189 OriginalParamType = OriginalParamRef->getPointeeType();
3190
3191 // FIXME: Resolve core issue (no number yet): if the original P is a
3192 // reference type and the transformed A is function type "noexcept F",
3193 // the deduced A can be F.
3194 QualType Tmp;
3195 if (A->isFunctionType() && S.IsFunctionConversion(A, DeducedA, Tmp))
3196 return Sema::TDK_Success;
3197
3198 Qualifiers AQuals = A.getQualifiers();
3199 Qualifiers DeducedAQuals = DeducedA.getQualifiers();
3200
3201 // Under Objective-C++ ARC, the deduced type may have implicitly
3202 // been given strong or (when dealing with a const reference)
3203 // unsafe_unretained lifetime. If so, update the original
3204 // qualifiers to include this lifetime.
3205 if (S.getLangOpts().ObjCAutoRefCount &&
3206 ((DeducedAQuals.getObjCLifetime() == Qualifiers::OCL_Strong &&
3207 AQuals.getObjCLifetime() == Qualifiers::OCL_None) ||
3208 (DeducedAQuals.hasConst() &&
3209 DeducedAQuals.getObjCLifetime() == Qualifiers::OCL_ExplicitNone))) {
3210 AQuals.setObjCLifetime(DeducedAQuals.getObjCLifetime());
3211 }
3212
3213 if (AQuals == DeducedAQuals) {
3214 // Qualifiers match; there's nothing to do.
3215 } else if (!DeducedAQuals.compatiblyIncludes(AQuals)) {
3216 return Failed();
3217 } else {
3218 // Qualifiers are compatible, so have the argument type adopt the
3219 // deduced argument type's qualifiers as if we had performed the
3220 // qualification conversion.
3221 A = Context.getQualifiedType(A.getUnqualifiedType(), DeducedAQuals);
3222 }
3223 }
3224
3225 // - The transformed A can be another pointer or pointer to member
3226 // type that can be converted to the deduced A via a function pointer
3227 // conversion and/or a qualification conversion.
3228 //
3229 // Also allow conversions which merely strip __attribute__((noreturn)) from
3230 // function types (recursively).
3231 bool ObjCLifetimeConversion = false;
3232 QualType ResultTy;
3233 if ((A->isAnyPointerType() || A->isMemberPointerType()) &&
3234 (S.IsQualificationConversion(A, DeducedA, false,
3235 ObjCLifetimeConversion) ||
3236 S.IsFunctionConversion(A, DeducedA, ResultTy)))
3237 return Sema::TDK_Success;
3238
3239 // - If P is a class and P has the form simple-template-id, then the
3240 // transformed A can be a derived class of the deduced A. [...]
3241 // [...] Likewise, if P is a pointer to a class of the form
3242 // simple-template-id, the transformed A can be a pointer to a
3243 // derived class pointed to by the deduced A.
3244 if (const PointerType *OriginalParamPtr
3245 = OriginalParamType->getAs<PointerType>()) {
3246 if (const PointerType *DeducedAPtr = DeducedA->getAs<PointerType>()) {
3247 if (const PointerType *APtr = A->getAs<PointerType>()) {
3248 if (A->getPointeeType()->isRecordType()) {
3249 OriginalParamType = OriginalParamPtr->getPointeeType();
3250 DeducedA = DeducedAPtr->getPointeeType();
3251 A = APtr->getPointeeType();
3252 }
3253 }
3254 }
3255 }
3256
3257 if (Context.hasSameUnqualifiedType(A, DeducedA))
3258 return Sema::TDK_Success;
3259
3260 if (A->isRecordType() && isSimpleTemplateIdType(OriginalParamType) &&
3261 S.IsDerivedFrom(Info.getLocation(), A, DeducedA))
3262 return Sema::TDK_Success;
3263
3264 return Failed();
3265}
3266
3267/// Find the pack index for a particular parameter index in an instantiation of
3268/// a function template with specific arguments.
3269///
3270/// \return The pack index for whichever pack produced this parameter, or -1
3271/// if this was not produced by a parameter. Intended to be used as the
3272/// ArgumentPackSubstitutionIndex for further substitutions.
3273// FIXME: We should track this in OriginalCallArgs so we don't need to
3274// reconstruct it here.
3275static unsigned getPackIndexForParam(Sema &S,
3276 FunctionTemplateDecl *FunctionTemplate,
3277 const MultiLevelTemplateArgumentList &Args,
3278 unsigned ParamIdx) {
3279 unsigned Idx = 0;
3280 for (auto *PD : FunctionTemplate->getTemplatedDecl()->parameters()) {
3281 if (PD->isParameterPack()) {
3282 unsigned NumExpansions =
3283 S.getNumArgumentsInExpansion(PD->getType(), Args).getValueOr(1);
3284 if (Idx + NumExpansions > ParamIdx)
3285 return ParamIdx - Idx;
3286 Idx += NumExpansions;
3287 } else {
3288 if (Idx == ParamIdx)
3289 return -1; // Not a pack expansion
3290 ++Idx;
3291 }
3292 }
3293
3294 llvm_unreachable("parameter index would not be produced from template")::llvm::llvm_unreachable_internal("parameter index would not be produced from template"
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 3294)
;
3295}
3296
3297/// Finish template argument deduction for a function template,
3298/// checking the deduced template arguments for completeness and forming
3299/// the function template specialization.
3300///
3301/// \param OriginalCallArgs If non-NULL, the original call arguments against
3302/// which the deduced argument types should be compared.
3303Sema::TemplateDeductionResult Sema::FinishTemplateArgumentDeduction(
3304 FunctionTemplateDecl *FunctionTemplate,
3305 SmallVectorImpl<DeducedTemplateArgument> &Deduced,
3306 unsigned NumExplicitlySpecified, FunctionDecl *&Specialization,
3307 TemplateDeductionInfo &Info,
3308 SmallVectorImpl<OriginalCallArg> const *OriginalCallArgs,
3309 bool PartialOverloading, llvm::function_ref<bool()> CheckNonDependent) {
3310 // Unevaluated SFINAE context.
3311 EnterExpressionEvaluationContext Unevaluated(
3312 *this, Sema::ExpressionEvaluationContext::Unevaluated);
3313 SFINAETrap Trap(*this);
3314
3315 // Enter a new template instantiation context while we instantiate the
3316 // actual function declaration.
3317 SmallVector<TemplateArgument, 4> DeducedArgs(Deduced.begin(), Deduced.end());
3318 InstantiatingTemplate Inst(
3319 *this, Info.getLocation(), FunctionTemplate, DeducedArgs,
3320 CodeSynthesisContext::DeducedTemplateArgumentSubstitution, Info);
3321 if (Inst.isInvalid())
3322 return TDK_InstantiationDepth;
3323
3324 ContextRAII SavedContext(*this, FunctionTemplate->getTemplatedDecl());
3325
3326 // C++ [temp.deduct.type]p2:
3327 // [...] or if any template argument remains neither deduced nor
3328 // explicitly specified, template argument deduction fails.
3329 SmallVector<TemplateArgument, 4> Builder;
3330 if (auto Result = ConvertDeducedTemplateArguments(
3331 *this, FunctionTemplate, /*IsDeduced*/true, Deduced, Info, Builder,
3332 CurrentInstantiationScope, NumExplicitlySpecified,
3333 PartialOverloading))
3334 return Result;
3335
3336 // C++ [temp.deduct.call]p10: [DR1391]
3337 // If deduction succeeds for all parameters that contain
3338 // template-parameters that participate in template argument deduction,
3339 // and all template arguments are explicitly specified, deduced, or
3340 // obtained from default template arguments, remaining parameters are then
3341 // compared with the corresponding arguments. For each remaining parameter
3342 // P with a type that was non-dependent before substitution of any
3343 // explicitly-specified template arguments, if the corresponding argument
3344 // A cannot be implicitly converted to P, deduction fails.
3345 if (CheckNonDependent())
3346 return TDK_NonDependentConversionFailure;
3347
3348 // Form the template argument list from the deduced template arguments.
3349 TemplateArgumentList *DeducedArgumentList
3350 = TemplateArgumentList::CreateCopy(Context, Builder);
3351 Info.reset(DeducedArgumentList);
3352
3353 // Substitute the deduced template arguments into the function template
3354 // declaration to produce the function template specialization.
3355 DeclContext *Owner = FunctionTemplate->getDeclContext();
3356 if (FunctionTemplate->getFriendObjectKind())
3357 Owner = FunctionTemplate->getLexicalDeclContext();
3358 MultiLevelTemplateArgumentList SubstArgs(*DeducedArgumentList);
3359 Specialization = cast_or_null<FunctionDecl>(
3360 SubstDecl(FunctionTemplate->getTemplatedDecl(), Owner, SubstArgs));
3361 if (!Specialization || Specialization->isInvalidDecl())
3362 return TDK_SubstitutionFailure;
3363
3364 assert(Specialization->getPrimaryTemplate()->getCanonicalDecl() ==((Specialization->getPrimaryTemplate()->getCanonicalDecl
() == FunctionTemplate->getCanonicalDecl()) ? static_cast<
void> (0) : __assert_fail ("Specialization->getPrimaryTemplate()->getCanonicalDecl() == FunctionTemplate->getCanonicalDecl()"
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 3365, __PRETTY_FUNCTION__))
3365 FunctionTemplate->getCanonicalDecl())((Specialization->getPrimaryTemplate()->getCanonicalDecl
() == FunctionTemplate->getCanonicalDecl()) ? static_cast<
void> (0) : __assert_fail ("Specialization->getPrimaryTemplate()->getCanonicalDecl() == FunctionTemplate->getCanonicalDecl()"
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 3365, __PRETTY_FUNCTION__))
;
3366
3367 // If the template argument list is owned by the function template
3368 // specialization, release it.
3369 if (Specialization->getTemplateSpecializationArgs() == DeducedArgumentList &&
3370 !Trap.hasErrorOccurred())
3371 Info.take();
3372
3373 // There may have been an error that did not prevent us from constructing a
3374 // declaration. Mark the declaration invalid and return with a substitution
3375 // failure.
3376 if (Trap.hasErrorOccurred()) {
3377 Specialization->setInvalidDecl(true);
3378 return TDK_SubstitutionFailure;
3379 }
3380
3381 if (OriginalCallArgs) {
3382 // C++ [temp.deduct.call]p4:
3383 // In general, the deduction process attempts to find template argument
3384 // values that will make the deduced A identical to A (after the type A
3385 // is transformed as described above). [...]
3386 llvm::SmallDenseMap<std::pair<unsigned, QualType>, QualType> DeducedATypes;
3387 for (unsigned I = 0, N = OriginalCallArgs->size(); I != N; ++I) {
3388 OriginalCallArg OriginalArg = (*OriginalCallArgs)[I];
3389
3390 auto ParamIdx = OriginalArg.ArgIdx;
3391 if (ParamIdx >= Specialization->getNumParams())
3392 // FIXME: This presumably means a pack ended up smaller than we
3393 // expected while deducing. Should this not result in deduction
3394 // failure? Can it even happen?
3395 continue;
3396
3397 QualType DeducedA;
3398 if (!OriginalArg.DecomposedParam) {
3399 // P is one of the function parameters, just look up its substituted
3400 // type.
3401 DeducedA = Specialization->getParamDecl(ParamIdx)->getType();
3402 } else {
3403 // P is a decomposed element of a parameter corresponding to a
3404 // braced-init-list argument. Substitute back into P to find the
3405 // deduced A.
3406 QualType &CacheEntry =
3407 DeducedATypes[{ParamIdx, OriginalArg.OriginalParamType}];
3408 if (CacheEntry.isNull()) {
3409 ArgumentPackSubstitutionIndexRAII PackIndex(
3410 *this, getPackIndexForParam(*this, FunctionTemplate, SubstArgs,
3411 ParamIdx));
3412 CacheEntry =
3413 SubstType(OriginalArg.OriginalParamType, SubstArgs,
3414 Specialization->getTypeSpecStartLoc(),
3415 Specialization->getDeclName());
3416 }
3417 DeducedA = CacheEntry;
3418 }
3419
3420 if (auto TDK =
3421 CheckOriginalCallArgDeduction(*this, Info, OriginalArg, DeducedA))
3422 return TDK;
3423 }
3424 }
3425
3426 // If we suppressed any diagnostics while performing template argument
3427 // deduction, and if we haven't already instantiated this declaration,
3428 // keep track of these diagnostics. They'll be emitted if this specialization
3429 // is actually used.
3430 if (Info.diag_begin() != Info.diag_end()) {
3431 SuppressedDiagnosticsMap::iterator
3432 Pos = SuppressedDiagnostics.find(Specialization->getCanonicalDecl());
3433 if (Pos == SuppressedDiagnostics.end())
3434 SuppressedDiagnostics[Specialization->getCanonicalDecl()]
3435 .append(Info.diag_begin(), Info.diag_end());
3436 }
3437
3438 return TDK_Success;
3439}
3440
3441/// Gets the type of a function for template-argument-deducton
3442/// purposes when it's considered as part of an overload set.
3443static QualType GetTypeOfFunction(Sema &S, const OverloadExpr::FindResult &R,
3444 FunctionDecl *Fn) {
3445 // We may need to deduce the return type of the function now.
3446 if (S.getLangOpts().CPlusPlus14 && Fn->getReturnType()->isUndeducedType() &&
3447 S.DeduceReturnType(Fn, R.Expression->getExprLoc(), /*Diagnose*/ false))
3448 return {};
3449
3450 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Fn))
3451 if (Method->isInstance()) {
3452 // An instance method that's referenced in a form that doesn't
3453 // look like a member pointer is just invalid.
3454 if (!R.HasFormOfMemberPointer)
3455 return {};
3456
3457 return S.Context.getMemberPointerType(Fn->getType(),
3458 S.Context.getTypeDeclType(Method->getParent()).getTypePtr());
3459 }
3460
3461 if (!R.IsAddressOfOperand) return Fn->getType();
3462 return S.Context.getPointerType(Fn->getType());
3463}
3464
3465/// Apply the deduction rules for overload sets.
3466///
3467/// \return the null type if this argument should be treated as an
3468/// undeduced context
3469static QualType
3470ResolveOverloadForDeduction(Sema &S, TemplateParameterList *TemplateParams,
3471 Expr *Arg, QualType ParamType,
3472 bool ParamWasReference) {
3473
3474 OverloadExpr::FindResult R = OverloadExpr::find(Arg);
3475
3476 OverloadExpr *Ovl = R.Expression;
3477
3478 // C++0x [temp.deduct.call]p4
3479 unsigned TDF = 0;
3480 if (ParamWasReference)
3481 TDF |= TDF_ParamWithReferenceType;
3482 if (R.IsAddressOfOperand)
3483 TDF |= TDF_IgnoreQualifiers;
3484
3485 // C++0x [temp.deduct.call]p6:
3486 // When P is a function type, pointer to function type, or pointer
3487 // to member function type:
3488
3489 if (!ParamType->isFunctionType() &&
3490 !ParamType->isFunctionPointerType() &&
3491 !ParamType->isMemberFunctionPointerType()) {
3492 if (Ovl->hasExplicitTemplateArgs()) {
3493 // But we can still look for an explicit specialization.
3494 if (FunctionDecl *ExplicitSpec
3495 = S.ResolveSingleFunctionTemplateSpecialization(Ovl))
3496 return GetTypeOfFunction(S, R, ExplicitSpec);
3497 }
3498
3499 DeclAccessPair DAP;
3500 if (FunctionDecl *Viable =
3501 S.resolveAddressOfOnlyViableOverloadCandidate(Arg, DAP))
3502 return GetTypeOfFunction(S, R, Viable);
3503
3504 return {};
3505 }
3506
3507 // Gather the explicit template arguments, if any.
3508 TemplateArgumentListInfo ExplicitTemplateArgs;
3509 if (Ovl->hasExplicitTemplateArgs())
3510 Ovl->copyTemplateArgumentsInto(ExplicitTemplateArgs);
3511 QualType Match;
3512 for (UnresolvedSetIterator I = Ovl->decls_begin(),
3513 E = Ovl->decls_end(); I != E; ++I) {
3514 NamedDecl *D = (*I)->getUnderlyingDecl();
3515
3516 if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(D)) {
3517 // - If the argument is an overload set containing one or more
3518 // function templates, the parameter is treated as a
3519 // non-deduced context.
3520 if (!Ovl->hasExplicitTemplateArgs())
3521 return {};
3522
3523 // Otherwise, see if we can resolve a function type
3524 FunctionDecl *Specialization = nullptr;
3525 TemplateDeductionInfo Info(Ovl->getNameLoc());
3526 if (S.DeduceTemplateArguments(FunTmpl, &ExplicitTemplateArgs,
3527 Specialization, Info))
3528 continue;
3529
3530 D = Specialization;
3531 }
3532
3533 FunctionDecl *Fn = cast<FunctionDecl>(D);
3534 QualType ArgType = GetTypeOfFunction(S, R, Fn);
3535 if (ArgType.isNull()) continue;
3536
3537 // Function-to-pointer conversion.
3538 if (!ParamWasReference && ParamType->isPointerType() &&
3539 ArgType->isFunctionType())
3540 ArgType = S.Context.getPointerType(ArgType);
3541
3542 // - If the argument is an overload set (not containing function
3543 // templates), trial argument deduction is attempted using each
3544 // of the members of the set. If deduction succeeds for only one
3545 // of the overload set members, that member is used as the
3546 // argument value for the deduction. If deduction succeeds for
3547 // more than one member of the overload set the parameter is
3548 // treated as a non-deduced context.
3549
3550 // We do all of this in a fresh context per C++0x [temp.deduct.type]p2:
3551 // Type deduction is done independently for each P/A pair, and
3552 // the deduced template argument values are then combined.
3553 // So we do not reject deductions which were made elsewhere.
3554 SmallVector<DeducedTemplateArgument, 8>
3555 Deduced(TemplateParams->size());
3556 TemplateDeductionInfo Info(Ovl->getNameLoc());
3557 Sema::TemplateDeductionResult Result
3558 = DeduceTemplateArgumentsByTypeMatch(S, TemplateParams, ParamType,
3559 ArgType, Info, Deduced, TDF);
3560 if (Result) continue;
3561 if (!Match.isNull())
3562 return {};
3563 Match = ArgType;
3564 }
3565
3566 return Match;
3567}
3568
3569/// Perform the adjustments to the parameter and argument types
3570/// described in C++ [temp.deduct.call].
3571///
3572/// \returns true if the caller should not attempt to perform any template
3573/// argument deduction based on this P/A pair because the argument is an
3574/// overloaded function set that could not be resolved.
3575static bool AdjustFunctionParmAndArgTypesForDeduction(
3576 Sema &S, TemplateParameterList *TemplateParams, unsigned FirstInnerIndex,
3577 QualType &ParamType, QualType &ArgType, Expr *Arg, unsigned &TDF) {
3578 // C++0x [temp.deduct.call]p3:
3579 // If P is a cv-qualified type, the top level cv-qualifiers of P's type
3580 // are ignored for type deduction.
3581 if (ParamType.hasQualifiers())
3582 ParamType = ParamType.getUnqualifiedType();
3583
3584 // [...] If P is a reference type, the type referred to by P is
3585 // used for type deduction.
3586 const ReferenceType *ParamRefType = ParamType->getAs<ReferenceType>();
3587 if (ParamRefType)
3588 ParamType = ParamRefType->getPointeeType();
3589
3590 // Overload sets usually make this parameter an undeduced context,
3591 // but there are sometimes special circumstances. Typically
3592 // involving a template-id-expr.
3593 if (ArgType == S.Context.OverloadTy) {
3594 ArgType = ResolveOverloadForDeduction(S, TemplateParams,
3595 Arg, ParamType,
3596 ParamRefType != nullptr);
3597 if (ArgType.isNull())
3598 return true;
3599 }
3600
3601 if (ParamRefType) {
3602 // If the argument has incomplete array type, try to complete its type.
3603 if (ArgType->isIncompleteArrayType()) {
3604 S.completeExprArrayBound(Arg);
3605 ArgType = Arg->getType();
3606 }
3607
3608 // C++1z [temp.deduct.call]p3:
3609 // If P is a forwarding reference and the argument is an lvalue, the type
3610 // "lvalue reference to A" is used in place of A for type deduction.
3611 if (isForwardingReference(QualType(ParamRefType, 0), FirstInnerIndex) &&
3612 Arg->isLValue())
3613 ArgType = S.Context.getLValueReferenceType(ArgType);
3614 } else {
3615 // C++ [temp.deduct.call]p2:
3616 // If P is not a reference type:
3617 // - If A is an array type, the pointer type produced by the
3618 // array-to-pointer standard conversion (4.2) is used in place of
3619 // A for type deduction; otherwise,
3620 if (ArgType->isArrayType())
3621 ArgType = S.Context.getArrayDecayedType(ArgType);
3622 // - If A is a function type, the pointer type produced by the
3623 // function-to-pointer standard conversion (4.3) is used in place
3624 // of A for type deduction; otherwise,
3625 else if (ArgType->isFunctionType())
3626 ArgType = S.Context.getPointerType(ArgType);
3627 else {
3628 // - If A is a cv-qualified type, the top level cv-qualifiers of A's
3629 // type are ignored for type deduction.
3630 ArgType = ArgType.getUnqualifiedType();
3631 }
3632 }
3633
3634 // C++0x [temp.deduct.call]p4:
3635 // In general, the deduction process attempts to find template argument
3636 // values that will make the deduced A identical to A (after the type A
3637 // is transformed as described above). [...]
3638 TDF = TDF_SkipNonDependent;
3639
3640 // - If the original P is a reference type, the deduced A (i.e., the
3641 // type referred to by the reference) can be more cv-qualified than
3642 // the transformed A.
3643 if (ParamRefType)
3644 TDF |= TDF_ParamWithReferenceType;
3645 // - The transformed A can be another pointer or pointer to member
3646 // type that can be converted to the deduced A via a qualification
3647 // conversion (4.4).
3648 if (ArgType->isPointerType() || ArgType->isMemberPointerType() ||
3649 ArgType->isObjCObjectPointerType())
3650 TDF |= TDF_IgnoreQualifiers;
3651 // - If P is a class and P has the form simple-template-id, then the
3652 // transformed A can be a derived class of the deduced A. Likewise,
3653 // if P is a pointer to a class of the form simple-template-id, the
3654 // transformed A can be a pointer to a derived class pointed to by
3655 // the deduced A.
3656 if (isSimpleTemplateIdType(ParamType) ||
3657 (isa<PointerType>(ParamType) &&
3658 isSimpleTemplateIdType(
3659 ParamType->getAs<PointerType>()->getPointeeType())))
3660 TDF |= TDF_DerivedClass;
3661
3662 return false;
3663}
3664
3665static bool
3666hasDeducibleTemplateParameters(Sema &S, FunctionTemplateDecl *FunctionTemplate,
3667 QualType T);
3668
3669static Sema::TemplateDeductionResult DeduceTemplateArgumentsFromCallArgument(
3670 Sema &S, TemplateParameterList *TemplateParams, unsigned FirstInnerIndex,
3671 QualType ParamType, Expr *Arg, TemplateDeductionInfo &Info,
3672 SmallVectorImpl<DeducedTemplateArgument> &Deduced,
3673 SmallVectorImpl<Sema::OriginalCallArg> &OriginalCallArgs,
3674 bool DecomposedParam, unsigned ArgIdx, unsigned TDF);
3675
3676/// Attempt template argument deduction from an initializer list
3677/// deemed to be an argument in a function call.
3678static Sema::TemplateDeductionResult DeduceFromInitializerList(
3679 Sema &S, TemplateParameterList *TemplateParams, QualType AdjustedParamType,
3680 InitListExpr *ILE, TemplateDeductionInfo &Info,
3681 SmallVectorImpl<DeducedTemplateArgument> &Deduced,
3682 SmallVectorImpl<Sema::OriginalCallArg> &OriginalCallArgs, unsigned ArgIdx,
3683 unsigned TDF) {
3684 // C++ [temp.deduct.call]p1: (CWG 1591)
3685 // If removing references and cv-qualifiers from P gives
3686 // std::initializer_list<P0> or P0[N] for some P0 and N and the argument is
3687 // a non-empty initializer list, then deduction is performed instead for
3688 // each element of the initializer list, taking P0 as a function template
3689 // parameter type and the initializer element as its argument
3690 //
3691 // We've already removed references and cv-qualifiers here.
3692 if (!ILE->getNumInits())
3693 return Sema::TDK_Success;
3694
3695 QualType ElTy;
3696 auto *ArrTy = S.Context.getAsArrayType(AdjustedParamType);
3697 if (ArrTy)
3698 ElTy = ArrTy->getElementType();
3699 else if (!S.isStdInitializerList(AdjustedParamType, &ElTy)) {
3700 // Otherwise, an initializer list argument causes the parameter to be
3701 // considered a non-deduced context
3702 return Sema::TDK_Success;
3703 }
3704
3705 // Deduction only needs to be done for dependent types.
3706 if (ElTy->isDependentType()) {
3707 for (Expr *E : ILE->inits()) {
3708 if (auto Result = DeduceTemplateArgumentsFromCallArgument(
3709 S, TemplateParams, 0, ElTy, E, Info, Deduced, OriginalCallArgs, true,
3710 ArgIdx, TDF))
3711 return Result;
3712 }
3713 }
3714
3715 // in the P0[N] case, if N is a non-type template parameter, N is deduced
3716 // from the length of the initializer list.
3717 if (auto *DependentArrTy = dyn_cast_or_null<DependentSizedArrayType>(ArrTy)) {
3718 // Determine the array bound is something we can deduce.
3719 if (NonTypeTemplateParmDecl *NTTP =
3720 getDeducedParameterFromExpr(Info, DependentArrTy->getSizeExpr())) {
3721 // We can perform template argument deduction for the given non-type
3722 // template parameter.
3723 // C++ [temp.deduct.type]p13:
3724 // The type of N in the type T[N] is std::size_t.
3725 QualType T = S.Context.getSizeType();
3726 llvm::APInt Size(S.Context.getIntWidth(T), ILE->getNumInits());
3727 if (auto Result = DeduceNonTypeTemplateArgument(
3728 S, TemplateParams, NTTP, llvm::APSInt(Size), T,
3729 /*ArrayBound=*/true, Info, Deduced))
3730 return Result;
3731 }
3732 }
3733
3734 return Sema::TDK_Success;
3735}
3736
3737/// Perform template argument deduction per [temp.deduct.call] for a
3738/// single parameter / argument pair.
3739static Sema::TemplateDeductionResult DeduceTemplateArgumentsFromCallArgument(
3740 Sema &S, TemplateParameterList *TemplateParams, unsigned FirstInnerIndex,
3741 QualType ParamType, Expr *Arg, TemplateDeductionInfo &Info,
3742 SmallVectorImpl<DeducedTemplateArgument> &Deduced,
3743 SmallVectorImpl<Sema::OriginalCallArg> &OriginalCallArgs,
3744 bool DecomposedParam, unsigned ArgIdx, unsigned TDF) {
3745 QualType ArgType = Arg->getType();
3746 QualType OrigParamType = ParamType;
3747
3748 // If P is a reference type [...]
3749 // If P is a cv-qualified type [...]
3750 if (AdjustFunctionParmAndArgTypesForDeduction(
3751 S, TemplateParams, FirstInnerIndex, ParamType, ArgType, Arg, TDF))
3752 return Sema::TDK_Success;
3753
3754 // If [...] the argument is a non-empty initializer list [...]
3755 if (InitListExpr *ILE = dyn_cast<InitListExpr>(Arg))
3756 return DeduceFromInitializerList(S, TemplateParams, ParamType, ILE, Info,
3757 Deduced, OriginalCallArgs, ArgIdx, TDF);
3758
3759 // [...] the deduction process attempts to find template argument values
3760 // that will make the deduced A identical to A
3761 //
3762 // Keep track of the argument type and corresponding parameter index,
3763 // so we can check for compatibility between the deduced A and A.
3764 OriginalCallArgs.push_back(
3765 Sema::OriginalCallArg(OrigParamType, DecomposedParam, ArgIdx, ArgType));
3766 return DeduceTemplateArgumentsByTypeMatch(S, TemplateParams, ParamType,
3767 ArgType, Info, Deduced, TDF);
3768}
3769
3770/// Perform template argument deduction from a function call
3771/// (C++ [temp.deduct.call]).
3772///
3773/// \param FunctionTemplate the function template for which we are performing
3774/// template argument deduction.
3775///
3776/// \param ExplicitTemplateArgs the explicit template arguments provided
3777/// for this call.
3778///
3779/// \param Args the function call arguments
3780///
3781/// \param Specialization if template argument deduction was successful,
3782/// this will be set to the function template specialization produced by
3783/// template argument deduction.
3784///
3785/// \param Info the argument will be updated to provide additional information
3786/// about template argument deduction.
3787///
3788/// \param CheckNonDependent A callback to invoke to check conversions for
3789/// non-dependent parameters, between deduction and substitution, per DR1391.
3790/// If this returns true, substitution will be skipped and we return
3791/// TDK_NonDependentConversionFailure. The callback is passed the parameter
3792/// types (after substituting explicit template arguments).
3793///
3794/// \returns the result of template argument deduction.
3795Sema::TemplateDeductionResult Sema::DeduceTemplateArguments(
3796 FunctionTemplateDecl *FunctionTemplate,
3797 TemplateArgumentListInfo *ExplicitTemplateArgs, ArrayRef<Expr *> Args,
3798 FunctionDecl *&Specialization, TemplateDeductionInfo &Info,
3799 bool PartialOverloading,
3800 llvm::function_ref<bool(ArrayRef<QualType>)> CheckNonDependent) {
3801 if (FunctionTemplate->isInvalidDecl())
1
Assuming the condition is false
2
Taking false branch
3802 return TDK_Invalid;
3803
3804 FunctionDecl *Function = FunctionTemplate->getTemplatedDecl();
3805 unsigned NumParams = Function->getNumParams();
3806
3807 unsigned FirstInnerIndex = getFirstInnerIndex(FunctionTemplate);
3808
3809 // C++ [temp.deduct.call]p1:
3810 // Template argument deduction is done by comparing each function template
3811 // parameter type (call it P) with the type of the corresponding argument
3812 // of the call (call it A) as described below.
3813 if (Args.size() < Function->getMinRequiredArguments() && !PartialOverloading)
3
Assuming the condition is false
3814 return TDK_TooFewArguments;
3815 else if (TooManyArguments(NumParams, Args.size(), PartialOverloading)) {
4
Taking false branch
3816 const FunctionProtoType *Proto
3817 = Function->getType()->getAs<FunctionProtoType>();
3818 if (Proto->isTemplateVariadic())
3819 /* Do nothing */;
3820 else if (!Proto->isVariadic())
3821 return TDK_TooManyArguments;
3822 }
3823
3824 // The types of the parameters from which we will perform template argument
3825 // deduction.
3826 LocalInstantiationScope InstScope(*this);
3827 TemplateParameterList *TemplateParams
3828 = FunctionTemplate->getTemplateParameters();
3829 SmallVector<DeducedTemplateArgument, 4> Deduced;
3830 SmallVector<QualType, 8> ParamTypes;
3831 unsigned NumExplicitlySpecified = 0;
3832 if (ExplicitTemplateArgs) {
5
Assuming 'ExplicitTemplateArgs' is null
6
Taking false branch
3833 TemplateDeductionResult Result =
3834 SubstituteExplicitTemplateArguments(FunctionTemplate,
3835 *ExplicitTemplateArgs,
3836 Deduced,
3837 ParamTypes,
3838 nullptr,
3839 Info);
3840 if (Result)
3841 return Result;
3842
3843 NumExplicitlySpecified = Deduced.size();
3844 } else {
3845 // Just fill in the parameter types from the function declaration.
3846 for (unsigned I = 0; I != NumParams; ++I)
7
Assuming 'I' is equal to 'NumParams'
8
Loop condition is false. Execution continues on line 3850
3847 ParamTypes.push_back(Function->getParamDecl(I)->getType());
3848 }
3849
3850 SmallVector<OriginalCallArg, 8> OriginalCallArgs;
3851
3852 // Deduce an argument of type ParamType from an expression with index ArgIdx.
3853 auto DeduceCallArgument = [&](QualType ParamType, unsigned ArgIdx) {
3854 // C++ [demp.deduct.call]p1: (DR1391)
3855 // Template argument deduction is done by comparing each function template
3856 // parameter that contains template-parameters that participate in
3857 // template argument deduction ...
3858 if (!hasDeducibleTemplateParameters(*this, FunctionTemplate, ParamType))
3859 return Sema::TDK_Success;
3860
3861 // ... with the type of the corresponding argument
3862 return DeduceTemplateArgumentsFromCallArgument(
3863 *this, TemplateParams, FirstInnerIndex, ParamType, Args[ArgIdx], Info, Deduced,
3864 OriginalCallArgs, /*Decomposed*/false, ArgIdx, /*TDF*/ 0);
3865 };
3866
3867 // Deduce template arguments from the function parameters.
3868 Deduced.resize(TemplateParams->size());
3869 SmallVector<QualType, 8> ParamTypesForArgChecking;
3870 for (unsigned ParamIdx = 0, NumParamTypes = ParamTypes.size(), ArgIdx = 0;
10
Loop condition is true. Entering loop body
3871 ParamIdx != NumParamTypes; ++ParamIdx) {
9
Assuming 'ParamIdx' is not equal to 'NumParamTypes'
3872 QualType ParamType = ParamTypes[ParamIdx];
3873
3874 const PackExpansionType *ParamExpansion =
3875 dyn_cast<PackExpansionType>(ParamType);
3876 if (!ParamExpansion) {
11
Assuming 'ParamExpansion' is non-null
12
Taking false branch
3877 // Simple case: matching a function parameter to a function argument.
3878 if (ArgIdx >= Args.size())
3879 break;
3880
3881 ParamTypesForArgChecking.push_back(ParamType);
3882 if (auto Result = DeduceCallArgument(ParamType, ArgIdx++))
3883 return Result;
3884
3885 continue;
3886 }
3887
3888 QualType ParamPattern = ParamExpansion->getPattern();
3889 PackDeductionScope PackScope(*this, TemplateParams, Deduced, Info,
13
Calling constructor for 'PackDeductionScope'
3890 ParamPattern);
3891
3892 // C++0x [temp.deduct.call]p1:
3893 // For a function parameter pack that occurs at the end of the
3894 // parameter-declaration-list, the type A of each remaining argument of
3895 // the call is compared with the type P of the declarator-id of the
3896 // function parameter pack. Each comparison deduces template arguments
3897 // for subsequent positions in the template parameter packs expanded by
3898 // the function parameter pack. When a function parameter pack appears
3899 // in a non-deduced context [not at the end of the list], the type of
3900 // that parameter pack is never deduced.
3901 //
3902 // FIXME: The above rule allows the size of the parameter pack to change
3903 // after we skip it (in the non-deduced case). That makes no sense, so
3904 // we instead notionally deduce the pack against N arguments, where N is
3905 // the length of the explicitly-specified pack if it's expanded by the
3906 // parameter pack and 0 otherwise, and we treat each deduction as a
3907 // non-deduced context.
3908 if (ParamIdx + 1 == NumParamTypes || PackScope.hasFixedArity()) {
3909 for (; ArgIdx < Args.size() && PackScope.hasNextElement();
3910 PackScope.nextPackElement(), ++ArgIdx) {
3911 ParamTypesForArgChecking.push_back(ParamPattern);
3912 if (auto Result = DeduceCallArgument(ParamPattern, ArgIdx))
3913 return Result;
3914 }
3915 } else {
3916 // If the parameter type contains an explicitly-specified pack that we
3917 // could not expand, skip the number of parameters notionally created
3918 // by the expansion.
3919 Optional<unsigned> NumExpansions = ParamExpansion->getNumExpansions();
3920 if (NumExpansions && !PackScope.isPartiallyExpanded()) {
3921 for (unsigned I = 0; I != *NumExpansions && ArgIdx < Args.size();
3922 ++I, ++ArgIdx) {
3923 ParamTypesForArgChecking.push_back(ParamPattern);
3924 // FIXME: Should we add OriginalCallArgs for these? What if the
3925 // corresponding argument is a list?
3926 PackScope.nextPackElement();
3927 }
3928 }
3929 }
3930
3931 // Build argument packs for each of the parameter packs expanded by this
3932 // pack expansion.
3933 if (auto Result = PackScope.finish())
3934 return Result;
3935 }
3936
3937 // Capture the context in which the function call is made. This is the context
3938 // that is needed when the accessibility of template arguments is checked.
3939 DeclContext *CallingCtx = CurContext;
3940
3941 return FinishTemplateArgumentDeduction(
3942 FunctionTemplate, Deduced, NumExplicitlySpecified, Specialization, Info,
3943 &OriginalCallArgs, PartialOverloading, [&, CallingCtx]() {
3944 ContextRAII SavedContext(*this, CallingCtx);
3945 return CheckNonDependent(ParamTypesForArgChecking);
3946 });
3947}
3948
3949QualType Sema::adjustCCAndNoReturn(QualType ArgFunctionType,
3950 QualType FunctionType,
3951 bool AdjustExceptionSpec) {
3952 if (ArgFunctionType.isNull())
3953 return ArgFunctionType;
3954
3955 const FunctionProtoType *FunctionTypeP =
3956 FunctionType->castAs<FunctionProtoType>();
3957 const FunctionProtoType *ArgFunctionTypeP =
3958 ArgFunctionType->getAs<FunctionProtoType>();
3959
3960 FunctionProtoType::ExtProtoInfo EPI = ArgFunctionTypeP->getExtProtoInfo();
3961 bool Rebuild = false;
3962
3963 CallingConv CC = FunctionTypeP->getCallConv();
3964 if (EPI.ExtInfo.getCC() != CC) {
3965 EPI.ExtInfo = EPI.ExtInfo.withCallingConv(CC);
3966 Rebuild = true;
3967 }
3968
3969 bool NoReturn = FunctionTypeP->getNoReturnAttr();
3970 if (EPI.ExtInfo.getNoReturn() != NoReturn) {
3971 EPI.ExtInfo = EPI.ExtInfo.withNoReturn(NoReturn);
3972 Rebuild = true;
3973 }
3974
3975 if (AdjustExceptionSpec && (FunctionTypeP->hasExceptionSpec() ||
3976 ArgFunctionTypeP->hasExceptionSpec())) {
3977 EPI.ExceptionSpec = FunctionTypeP->getExtProtoInfo().ExceptionSpec;
3978 Rebuild = true;
3979 }
3980
3981 if (!Rebuild)
3982 return ArgFunctionType;
3983
3984 return Context.getFunctionType(ArgFunctionTypeP->getReturnType(),
3985 ArgFunctionTypeP->getParamTypes(), EPI);
3986}
3987
3988/// Deduce template arguments when taking the address of a function
3989/// template (C++ [temp.deduct.funcaddr]) or matching a specialization to
3990/// a template.
3991///
3992/// \param FunctionTemplate the function template for which we are performing
3993/// template argument deduction.
3994///
3995/// \param ExplicitTemplateArgs the explicitly-specified template
3996/// arguments.
3997///
3998/// \param ArgFunctionType the function type that will be used as the
3999/// "argument" type (A) when performing template argument deduction from the
4000/// function template's function type. This type may be NULL, if there is no
4001/// argument type to compare against, in C++0x [temp.arg.explicit]p3.
4002///
4003/// \param Specialization if template argument deduction was successful,
4004/// this will be set to the function template specialization produced by
4005/// template argument deduction.
4006///
4007/// \param Info the argument will be updated to provide additional information
4008/// about template argument deduction.
4009///
4010/// \param IsAddressOfFunction If \c true, we are deducing as part of taking
4011/// the address of a function template per [temp.deduct.funcaddr] and
4012/// [over.over]. If \c false, we are looking up a function template
4013/// specialization based on its signature, per [temp.deduct.decl].
4014///
4015/// \returns the result of template argument deduction.
4016Sema::TemplateDeductionResult Sema::DeduceTemplateArguments(
4017 FunctionTemplateDecl *FunctionTemplate,
4018 TemplateArgumentListInfo *ExplicitTemplateArgs, QualType ArgFunctionType,
4019 FunctionDecl *&Specialization, TemplateDeductionInfo &Info,
4020 bool IsAddressOfFunction) {
4021 if (FunctionTemplate->isInvalidDecl())
4022 return TDK_Invalid;
4023
4024 FunctionDecl *Function = FunctionTemplate->getTemplatedDecl();
4025 TemplateParameterList *TemplateParams
4026 = FunctionTemplate->getTemplateParameters();
4027 QualType FunctionType = Function->getType();
4028
4029 // Substitute any explicit template arguments.
4030 LocalInstantiationScope InstScope(*this);
4031 SmallVector<DeducedTemplateArgument, 4> Deduced;
4032 unsigned NumExplicitlySpecified = 0;
4033 SmallVector<QualType, 4> ParamTypes;
4034 if (ExplicitTemplateArgs) {
4035 if (TemplateDeductionResult Result
4036 = SubstituteExplicitTemplateArguments(FunctionTemplate,
4037 *ExplicitTemplateArgs,
4038 Deduced, ParamTypes,
4039 &FunctionType, Info))
4040 return Result;
4041
4042 NumExplicitlySpecified = Deduced.size();
4043 }
4044
4045 // When taking the address of a function, we require convertibility of
4046 // the resulting function type. Otherwise, we allow arbitrary mismatches
4047 // of calling convention and noreturn.
4048 if (!IsAddressOfFunction)
4049 ArgFunctionType = adjustCCAndNoReturn(ArgFunctionType, FunctionType,
4050 /*AdjustExceptionSpec*/false);
4051
4052 // Unevaluated SFINAE context.
4053 EnterExpressionEvaluationContext Unevaluated(
4054 *this, Sema::ExpressionEvaluationContext::Unevaluated);
4055 SFINAETrap Trap(*this);
4056
4057 Deduced.resize(TemplateParams->size());
4058
4059 // If the function has a deduced return type, substitute it for a dependent
4060 // type so that we treat it as a non-deduced context in what follows. If we
4061 // are looking up by signature, the signature type should also have a deduced
4062 // return type, which we instead expect to exactly match.
4063 bool HasDeducedReturnType = false;
4064 if (getLangOpts().CPlusPlus14 && IsAddressOfFunction &&
4065 Function->getReturnType()->getContainedAutoType()) {
4066 FunctionType = SubstAutoType(FunctionType, Context.DependentTy);
4067 HasDeducedReturnType = true;
4068 }
4069
4070 if (!ArgFunctionType.isNull()) {
4071 unsigned TDF =
4072 TDF_TopLevelParameterTypeList | TDF_AllowCompatibleFunctionType;
4073 // Deduce template arguments from the function type.
4074 if (TemplateDeductionResult Result
4075 = DeduceTemplateArgumentsByTypeMatch(*this, TemplateParams,
4076 FunctionType, ArgFunctionType,
4077 Info, Deduced, TDF))
4078 return Result;
4079 }
4080
4081 if (TemplateDeductionResult Result
4082 = FinishTemplateArgumentDeduction(FunctionTemplate, Deduced,
4083 NumExplicitlySpecified,
4084 Specialization, Info))
4085 return Result;
4086
4087 // If the function has a deduced return type, deduce it now, so we can check
4088 // that the deduced function type matches the requested type.
4089 if (HasDeducedReturnType &&
4090 Specialization->getReturnType()->isUndeducedType() &&
4091 DeduceReturnType(Specialization, Info.getLocation(), false))
4092 return TDK_MiscellaneousDeductionFailure;
4093
4094 // If the function has a dependent exception specification, resolve it now,
4095 // so we can check that the exception specification matches.
4096 auto *SpecializationFPT =
4097 Specialization->getType()->castAs<FunctionProtoType>();
4098 if (getLangOpts().CPlusPlus17 &&
4099 isUnresolvedExceptionSpec(SpecializationFPT->getExceptionSpecType()) &&
4100 !ResolveExceptionSpec(Info.getLocation(), SpecializationFPT))
4101 return TDK_MiscellaneousDeductionFailure;
4102
4103 // Adjust the exception specification of the argument to match the
4104 // substituted and resolved type we just formed. (Calling convention and
4105 // noreturn can't be dependent, so we don't actually need this for them
4106 // right now.)
4107 QualType SpecializationType = Specialization->getType();
4108 if (!IsAddressOfFunction)
4109 ArgFunctionType = adjustCCAndNoReturn(ArgFunctionType, SpecializationType,
4110 /*AdjustExceptionSpec*/true);
4111
4112 // If the requested function type does not match the actual type of the
4113 // specialization with respect to arguments of compatible pointer to function
4114 // types, template argument deduction fails.
4115 if (!ArgFunctionType.isNull()) {
4116 if (IsAddressOfFunction &&
4117 !isSameOrCompatibleFunctionType(
4118 Context.getCanonicalType(SpecializationType),
4119 Context.getCanonicalType(ArgFunctionType)))
4120 return TDK_MiscellaneousDeductionFailure;
4121
4122 if (!IsAddressOfFunction &&
4123 !Context.hasSameType(SpecializationType, ArgFunctionType))
4124 return TDK_MiscellaneousDeductionFailure;
4125 }
4126
4127 return TDK_Success;
4128}
4129
4130/// Deduce template arguments for a templated conversion
4131/// function (C++ [temp.deduct.conv]) and, if successful, produce a
4132/// conversion function template specialization.
4133Sema::TemplateDeductionResult
4134Sema::DeduceTemplateArguments(FunctionTemplateDecl *ConversionTemplate,
4135 QualType ToType,
4136 CXXConversionDecl *&Specialization,
4137 TemplateDeductionInfo &Info) {
4138 if (ConversionTemplate->isInvalidDecl())
4139 return TDK_Invalid;
4140
4141 CXXConversionDecl *ConversionGeneric
4142 = cast<CXXConversionDecl>(ConversionTemplate->getTemplatedDecl());
4143
4144 QualType FromType = ConversionGeneric->getConversionType();
4145
4146 // Canonicalize the types for deduction.
4147 QualType P = Context.getCanonicalType(FromType);
4148 QualType A = Context.getCanonicalType(ToType);
4149
4150 // C++0x [temp.deduct.conv]p2:
4151 // If P is a reference type, the type referred to by P is used for
4152 // type deduction.
4153 if (const ReferenceType *PRef = P->getAs<ReferenceType>())
4154 P = PRef->getPointeeType();
4155
4156 // C++0x [temp.deduct.conv]p4:
4157 // [...] If A is a reference type, the type referred to by A is used
4158 // for type deduction.
4159 if (const ReferenceType *ARef = A->getAs<ReferenceType>()) {
4160 A = ARef->getPointeeType();
4161 // We work around a defect in the standard here: cv-qualifiers are also
4162 // removed from P and A in this case, unless P was a reference type. This
4163 // seems to mostly match what other compilers are doing.
4164 if (!FromType->getAs<ReferenceType>()) {
4165 A = A.getUnqualifiedType();
4166 P = P.getUnqualifiedType();
4167 }
4168
4169 // C++ [temp.deduct.conv]p3:
4170 //
4171 // If A is not a reference type:
4172 } else {
4173 assert(!A->isReferenceType() && "Reference types were handled above")((!A->isReferenceType() && "Reference types were handled above"
) ? static_cast<void> (0) : __assert_fail ("!A->isReferenceType() && \"Reference types were handled above\""
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 4173, __PRETTY_FUNCTION__))
;
4174
4175 // - If P is an array type, the pointer type produced by the
4176 // array-to-pointer standard conversion (4.2) is used in place
4177 // of P for type deduction; otherwise,
4178 if (P->isArrayType())
4179 P = Context.getArrayDecayedType(P);
4180 // - If P is a function type, the pointer type produced by the
4181 // function-to-pointer standard conversion (4.3) is used in
4182 // place of P for type deduction; otherwise,
4183 else if (P->isFunctionType())
4184 P = Context.getPointerType(P);
4185 // - If P is a cv-qualified type, the top level cv-qualifiers of
4186 // P's type are ignored for type deduction.
4187 else
4188 P = P.getUnqualifiedType();
4189
4190 // C++0x [temp.deduct.conv]p4:
4191 // If A is a cv-qualified type, the top level cv-qualifiers of A's
4192 // type are ignored for type deduction. If A is a reference type, the type
4193 // referred to by A is used for type deduction.
4194 A = A.getUnqualifiedType();
4195 }
4196
4197 // Unevaluated SFINAE context.
4198 EnterExpressionEvaluationContext Unevaluated(
4199 *this, Sema::ExpressionEvaluationContext::Unevaluated);
4200 SFINAETrap Trap(*this);
4201
4202 // C++ [temp.deduct.conv]p1:
4203 // Template argument deduction is done by comparing the return
4204 // type of the template conversion function (call it P) with the
4205 // type that is required as the result of the conversion (call it
4206 // A) as described in 14.8.2.4.
4207 TemplateParameterList *TemplateParams
4208 = ConversionTemplate->getTemplateParameters();
4209 SmallVector<DeducedTemplateArgument, 4> Deduced;
4210 Deduced.resize(TemplateParams->size());
4211
4212 // C++0x [temp.deduct.conv]p4:
4213 // In general, the deduction process attempts to find template
4214 // argument values that will make the deduced A identical to
4215 // A. However, there are two cases that allow a difference:
4216 unsigned TDF = 0;
4217 // - If the original A is a reference type, A can be more
4218 // cv-qualified than the deduced A (i.e., the type referred to
4219 // by the reference)
4220 if (ToType->isReferenceType())
4221 TDF |= TDF_ArgWithReferenceType;
4222 // - The deduced A can be another pointer or pointer to member
4223 // type that can be converted to A via a qualification
4224 // conversion.
4225 //
4226 // (C++0x [temp.deduct.conv]p6 clarifies that this only happens when
4227 // both P and A are pointers or member pointers. In this case, we
4228 // just ignore cv-qualifiers completely).
4229 if ((P->isPointerType() && A->isPointerType()) ||
4230 (P->isMemberPointerType() && A->isMemberPointerType()))
4231 TDF |= TDF_IgnoreQualifiers;
4232 if (TemplateDeductionResult Result
4233 = DeduceTemplateArgumentsByTypeMatch(*this, TemplateParams,
4234 P, A, Info, Deduced, TDF))
4235 return Result;
4236
4237 // Create an Instantiation Scope for finalizing the operator.
4238 LocalInstantiationScope InstScope(*this);
4239 // Finish template argument deduction.
4240 FunctionDecl *ConversionSpecialized = nullptr;
4241 TemplateDeductionResult Result
4242 = FinishTemplateArgumentDeduction(ConversionTemplate, Deduced, 0,
4243 ConversionSpecialized, Info);
4244 Specialization = cast_or_null<CXXConversionDecl>(ConversionSpecialized);
4245 return Result;
4246}
4247
4248/// Deduce template arguments for a function template when there is
4249/// nothing to deduce against (C++0x [temp.arg.explicit]p3).
4250///
4251/// \param FunctionTemplate the function template for which we are performing
4252/// template argument deduction.
4253///
4254/// \param ExplicitTemplateArgs the explicitly-specified template
4255/// arguments.
4256///
4257/// \param Specialization if template argument deduction was successful,
4258/// this will be set to the function template specialization produced by
4259/// template argument deduction.
4260///
4261/// \param Info the argument will be updated to provide additional information
4262/// about template argument deduction.
4263///
4264/// \param IsAddressOfFunction If \c true, we are deducing as part of taking
4265/// the address of a function template in a context where we do not have a
4266/// target type, per [over.over]. If \c false, we are looking up a function
4267/// template specialization based on its signature, which only happens when
4268/// deducing a function parameter type from an argument that is a template-id
4269/// naming a function template specialization.
4270///
4271/// \returns the result of template argument deduction.
4272Sema::TemplateDeductionResult Sema::DeduceTemplateArguments(
4273 FunctionTemplateDecl *FunctionTemplate,
4274 TemplateArgumentListInfo *ExplicitTemplateArgs,
4275 FunctionDecl *&Specialization, TemplateDeductionInfo &Info,
4276 bool IsAddressOfFunction) {
4277 return DeduceTemplateArguments(FunctionTemplate, ExplicitTemplateArgs,
4278 QualType(), Specialization, Info,
4279 IsAddressOfFunction);
4280}
4281
4282namespace {
4283 struct DependentAuto { bool IsPack; };
4284
4285 /// Substitute the 'auto' specifier or deduced template specialization type
4286 /// specifier within a type for a given replacement type.
4287 class SubstituteDeducedTypeTransform :
4288 public TreeTransform<SubstituteDeducedTypeTransform> {
4289 QualType Replacement;
4290 bool ReplacementIsPack;
4291 bool UseTypeSugar;
4292
4293 public:
4294 SubstituteDeducedTypeTransform(Sema &SemaRef, DependentAuto DA)
4295 : TreeTransform<SubstituteDeducedTypeTransform>(SemaRef), Replacement(),
4296 ReplacementIsPack(DA.IsPack), UseTypeSugar(true) {}
4297
4298 SubstituteDeducedTypeTransform(Sema &SemaRef, QualType Replacement,
4299 bool UseTypeSugar = true)
4300 : TreeTransform<SubstituteDeducedTypeTransform>(SemaRef),
4301 Replacement(Replacement), ReplacementIsPack(false),
4302 UseTypeSugar(UseTypeSugar) {}
4303
4304 QualType TransformDesugared(TypeLocBuilder &TLB, DeducedTypeLoc TL) {
4305 assert(isa<TemplateTypeParmType>(Replacement) &&((isa<TemplateTypeParmType>(Replacement) && "unexpected unsugared replacement kind"
) ? static_cast<void> (0) : __assert_fail ("isa<TemplateTypeParmType>(Replacement) && \"unexpected unsugared replacement kind\""
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 4306, __PRETTY_FUNCTION__))
4306 "unexpected unsugared replacement kind")((isa<TemplateTypeParmType>(Replacement) && "unexpected unsugared replacement kind"
) ? static_cast<void> (0) : __assert_fail ("isa<TemplateTypeParmType>(Replacement) && \"unexpected unsugared replacement kind\""
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 4306, __PRETTY_FUNCTION__))
;
4307 QualType Result = Replacement;
4308 TemplateTypeParmTypeLoc NewTL = TLB.push<TemplateTypeParmTypeLoc>(Result);
4309 NewTL.setNameLoc(TL.getNameLoc());
4310 return Result;
4311 }
4312
4313 QualType TransformAutoType(TypeLocBuilder &TLB, AutoTypeLoc TL) {
4314 // If we're building the type pattern to deduce against, don't wrap the
4315 // substituted type in an AutoType. Certain template deduction rules
4316 // apply only when a template type parameter appears directly (and not if
4317 // the parameter is found through desugaring). For instance:
4318 // auto &&lref = lvalue;
4319 // must transform into "rvalue reference to T" not "rvalue reference to
4320 // auto type deduced as T" in order for [temp.deduct.call]p3 to apply.
4321 //
4322 // FIXME: Is this still necessary?
4323 if (!UseTypeSugar)
4324 return TransformDesugared(TLB, TL);
4325
4326 QualType Result = SemaRef.Context.getAutoType(
4327 Replacement, TL.getTypePtr()->getKeyword(), Replacement.isNull(),
4328 ReplacementIsPack);
4329 auto NewTL = TLB.push<AutoTypeLoc>(Result);
4330 NewTL.setNameLoc(TL.getNameLoc());
4331 return Result;
4332 }
4333
4334 QualType TransformDeducedTemplateSpecializationType(
4335 TypeLocBuilder &TLB, DeducedTemplateSpecializationTypeLoc TL) {
4336 if (!UseTypeSugar)
4337 return TransformDesugared(TLB, TL);
4338
4339 QualType Result = SemaRef.Context.getDeducedTemplateSpecializationType(
4340 TL.getTypePtr()->getTemplateName(),
4341 Replacement, Replacement.isNull());
4342 auto NewTL = TLB.push<DeducedTemplateSpecializationTypeLoc>(Result);
4343 NewTL.setNameLoc(TL.getNameLoc());
4344 return Result;
4345 }
4346
4347 ExprResult TransformLambdaExpr(LambdaExpr *E) {
4348 // Lambdas never need to be transformed.
4349 return E;
4350 }
4351
4352 QualType Apply(TypeLoc TL) {
4353 // Create some scratch storage for the transformed type locations.
4354 // FIXME: We're just going to throw this information away. Don't build it.
4355 TypeLocBuilder TLB;
4356 TLB.reserve(TL.getFullDataSize());
4357 return TransformType(TLB, TL);
4358 }
4359 };
4360
4361} // namespace
4362
4363Sema::DeduceAutoResult
4364Sema::DeduceAutoType(TypeSourceInfo *Type, Expr *&Init, QualType &Result,
4365 Optional<unsigned> DependentDeductionDepth) {
4366 return DeduceAutoType(Type->getTypeLoc(), Init, Result,
4367 DependentDeductionDepth);
4368}
4369
4370/// Attempt to produce an informative diagostic explaining why auto deduction
4371/// failed.
4372/// \return \c true if diagnosed, \c false if not.
4373static bool diagnoseAutoDeductionFailure(Sema &S,
4374 Sema::TemplateDeductionResult TDK,
4375 TemplateDeductionInfo &Info,
4376 ArrayRef<SourceRange> Ranges) {
4377 switch (TDK) {
4378 case Sema::TDK_Inconsistent: {
4379 // Inconsistent deduction means we were deducing from an initializer list.
4380 auto D = S.Diag(Info.getLocation(), diag::err_auto_inconsistent_deduction);
4381 D << Info.FirstArg << Info.SecondArg;
4382 for (auto R : Ranges)
4383 D << R;
4384 return true;
4385 }
4386
4387 // FIXME: Are there other cases for which a custom diagnostic is more useful
4388 // than the basic "types don't match" diagnostic?
4389
4390 default:
4391 return false;
4392 }
4393}
4394
4395/// Deduce the type for an auto type-specifier (C++11 [dcl.spec.auto]p6)
4396///
4397/// Note that this is done even if the initializer is dependent. (This is
4398/// necessary to support partial ordering of templates using 'auto'.)
4399/// A dependent type will be produced when deducing from a dependent type.
4400///
4401/// \param Type the type pattern using the auto type-specifier.
4402/// \param Init the initializer for the variable whose type is to be deduced.
4403/// \param Result if type deduction was successful, this will be set to the
4404/// deduced type.
4405/// \param DependentDeductionDepth Set if we should permit deduction in
4406/// dependent cases. This is necessary for template partial ordering with
4407/// 'auto' template parameters. The value specified is the template
4408/// parameter depth at which we should perform 'auto' deduction.
4409Sema::DeduceAutoResult
4410Sema::DeduceAutoType(TypeLoc Type, Expr *&Init, QualType &Result,
4411 Optional<unsigned> DependentDeductionDepth) {
4412 if (Init->getType()->isNonOverloadPlaceholderType()) {
4413 ExprResult NonPlaceholder = CheckPlaceholderExpr(Init);
4414 if (NonPlaceholder.isInvalid())
4415 return DAR_FailedAlreadyDiagnosed;
4416 Init = NonPlaceholder.get();
4417 }
4418
4419 DependentAuto DependentResult = {
4420 /*.IsPack = */ (bool)Type.getAs<PackExpansionTypeLoc>()};
4421
4422 if (!DependentDeductionDepth &&
4423 (Type.getType()->isDependentType() || Init->isTypeDependent())) {
4424 Result = SubstituteDeducedTypeTransform(*this, DependentResult).Apply(Type);
4425 assert(!Result.isNull() && "substituting DependentTy can't fail")((!Result.isNull() && "substituting DependentTy can't fail"
) ? static_cast<void> (0) : __assert_fail ("!Result.isNull() && \"substituting DependentTy can't fail\""
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 4425, __PRETTY_FUNCTION__))
;
4426 return DAR_Succeeded;
4427 }
4428
4429 // Find the depth of template parameter to synthesize.
4430 unsigned Depth = DependentDeductionDepth.getValueOr(0);
4431
4432 // If this is a 'decltype(auto)' specifier, do the decltype dance.
4433 // Since 'decltype(auto)' can only occur at the top of the type, we
4434 // don't need to go digging for it.
4435 if (const AutoType *AT = Type.getType()->getAs<AutoType>()) {
4436 if (AT->isDecltypeAuto()) {
4437 if (isa<InitListExpr>(Init)) {
4438 Diag(Init->getBeginLoc(), diag::err_decltype_auto_initializer_list);
4439 return DAR_FailedAlreadyDiagnosed;
4440 }
4441
4442 ExprResult ER = CheckPlaceholderExpr(Init);
4443 if (ER.isInvalid())
4444 return DAR_FailedAlreadyDiagnosed;
4445 Init = ER.get();
4446 QualType Deduced = BuildDecltypeType(Init, Init->getBeginLoc(), false);
4447 if (Deduced.isNull())
4448 return DAR_FailedAlreadyDiagnosed;
4449 // FIXME: Support a non-canonical deduced type for 'auto'.
4450 Deduced = Context.getCanonicalType(Deduced);
4451 Result = SubstituteDeducedTypeTransform(*this, Deduced).Apply(Type);
4452 if (Result.isNull())
4453 return DAR_FailedAlreadyDiagnosed;
4454 return DAR_Succeeded;
4455 } else if (!getLangOpts().CPlusPlus) {
4456 if (isa<InitListExpr>(Init)) {
4457 Diag(Init->getBeginLoc(), diag::err_auto_init_list_from_c);
4458 return DAR_FailedAlreadyDiagnosed;
4459 }
4460 }
4461 }
4462
4463 SourceLocation Loc = Init->getExprLoc();
4464
4465 LocalInstantiationScope InstScope(*this);
4466
4467 // Build template<class TemplParam> void Func(FuncParam);
4468 TemplateTypeParmDecl *TemplParam = TemplateTypeParmDecl::Create(
4469 Context, nullptr, SourceLocation(), Loc, Depth, 0, nullptr, false, false);
4470 QualType TemplArg = QualType(TemplParam->getTypeForDecl(), 0);
4471 NamedDecl *TemplParamPtr = TemplParam;
4472 FixedSizeTemplateParameterListStorage<1, false> TemplateParamsSt(
4473 Loc, Loc, TemplParamPtr, Loc, nullptr);
4474
4475 QualType FuncParam =
4476 SubstituteDeducedTypeTransform(*this, TemplArg, /*UseTypeSugar*/false)
4477 .Apply(Type);
4478 assert(!FuncParam.isNull() &&((!FuncParam.isNull() && "substituting template parameter for 'auto' failed"
) ? static_cast<void> (0) : __assert_fail ("!FuncParam.isNull() && \"substituting template parameter for 'auto' failed\""
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 4479, __PRETTY_FUNCTION__))
4479 "substituting template parameter for 'auto' failed")((!FuncParam.isNull() && "substituting template parameter for 'auto' failed"
) ? static_cast<void> (0) : __assert_fail ("!FuncParam.isNull() && \"substituting template parameter for 'auto' failed\""
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 4479, __PRETTY_FUNCTION__))
;
4480
4481 // Deduce type of TemplParam in Func(Init)
4482 SmallVector<DeducedTemplateArgument, 1> Deduced;
4483 Deduced.resize(1);
4484
4485 TemplateDeductionInfo Info(Loc, Depth);
4486
4487 // If deduction failed, don't diagnose if the initializer is dependent; it
4488 // might acquire a matching type in the instantiation.
4489 auto DeductionFailed = [&](TemplateDeductionResult TDK,
4490 ArrayRef<SourceRange> Ranges) -> DeduceAutoResult {
4491 if (Init->isTypeDependent()) {
4492 Result =
4493 SubstituteDeducedTypeTransform(*this, DependentResult).Apply(Type);
4494 assert(!Result.isNull() && "substituting DependentTy can't fail")((!Result.isNull() && "substituting DependentTy can't fail"
) ? static_cast<void> (0) : __assert_fail ("!Result.isNull() && \"substituting DependentTy can't fail\""
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 4494, __PRETTY_FUNCTION__))
;
4495 return DAR_Succeeded;
4496 }
4497 if (diagnoseAutoDeductionFailure(*this, TDK, Info, Ranges))
4498 return DAR_FailedAlreadyDiagnosed;
4499 return DAR_Failed;
4500 };
4501
4502 SmallVector<OriginalCallArg, 4> OriginalCallArgs;
4503
4504 InitListExpr *InitList = dyn_cast<InitListExpr>(Init);
4505 if (InitList) {
4506 // Notionally, we substitute std::initializer_list<T> for 'auto' and deduce
4507 // against that. Such deduction only succeeds if removing cv-qualifiers and
4508 // references results in std::initializer_list<T>.
4509 if (!Type.getType().getNonReferenceType()->getAs<AutoType>())
4510 return DAR_Failed;
4511
4512 SourceRange DeducedFromInitRange;
4513 for (unsigned i = 0, e = InitList->getNumInits(); i < e; ++i) {
4514 Expr *Init = InitList->getInit(i);
4515
4516 if (auto TDK = DeduceTemplateArgumentsFromCallArgument(
4517 *this, TemplateParamsSt.get(), 0, TemplArg, Init,
4518 Info, Deduced, OriginalCallArgs, /*Decomposed*/ true,
4519 /*ArgIdx*/ 0, /*TDF*/ 0))
4520 return DeductionFailed(TDK, {DeducedFromInitRange,
4521 Init->getSourceRange()});
4522
4523 if (DeducedFromInitRange.isInvalid() &&
4524 Deduced[0].getKind() != TemplateArgument::Null)
4525 DeducedFromInitRange = Init->getSourceRange();
4526 }
4527 } else {
4528 if (!getLangOpts().CPlusPlus && Init->refersToBitField()) {
4529 Diag(Loc, diag::err_auto_bitfield);
4530 return DAR_FailedAlreadyDiagnosed;
4531 }
4532
4533 if (auto TDK = DeduceTemplateArgumentsFromCallArgument(
4534 *this, TemplateParamsSt.get(), 0, FuncParam, Init, Info, Deduced,
4535 OriginalCallArgs, /*Decomposed*/ false, /*ArgIdx*/ 0, /*TDF*/ 0))
4536 return DeductionFailed(TDK, {});
4537 }
4538
4539 // Could be null if somehow 'auto' appears in a non-deduced context.
4540 if (Deduced[0].getKind() != TemplateArgument::Type)
4541 return DeductionFailed(TDK_Incomplete, {});
4542
4543 QualType DeducedType = Deduced[0].getAsType();
4544
4545 if (InitList) {
4546 DeducedType = BuildStdInitializerList(DeducedType, Loc);
4547 if (DeducedType.isNull())
4548 return DAR_FailedAlreadyDiagnosed;
4549 }
4550
4551 Result = SubstituteDeducedTypeTransform(*this, DeducedType).Apply(Type);
4552 if (Result.isNull())
4553 return DAR_FailedAlreadyDiagnosed;
4554
4555 // Check that the deduced argument type is compatible with the original
4556 // argument type per C++ [temp.deduct.call]p4.
4557 QualType DeducedA = InitList ? Deduced[0].getAsType() : Result;
4558 for (const OriginalCallArg &OriginalArg : OriginalCallArgs) {
4559 assert((bool)InitList == OriginalArg.DecomposedParam &&(((bool)InitList == OriginalArg.DecomposedParam && "decomposed non-init-list in auto deduction?"
) ? static_cast<void> (0) : __assert_fail ("(bool)InitList == OriginalArg.DecomposedParam && \"decomposed non-init-list in auto deduction?\""
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 4560, __PRETTY_FUNCTION__))
4560 "decomposed non-init-list in auto deduction?")(((bool)InitList == OriginalArg.DecomposedParam && "decomposed non-init-list in auto deduction?"
) ? static_cast<void> (0) : __assert_fail ("(bool)InitList == OriginalArg.DecomposedParam && \"decomposed non-init-list in auto deduction?\""
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 4560, __PRETTY_FUNCTION__))
;
4561 if (auto TDK =
4562 CheckOriginalCallArgDeduction(*this, Info, OriginalArg, DeducedA)) {
4563 Result = QualType();
4564 return DeductionFailed(TDK, {});
4565 }
4566 }
4567
4568 return DAR_Succeeded;
4569}
4570
4571QualType Sema::SubstAutoType(QualType TypeWithAuto,
4572 QualType TypeToReplaceAuto) {
4573 if (TypeToReplaceAuto->isDependentType())
4574 return SubstituteDeducedTypeTransform(
4575 *this, DependentAuto{
4576 TypeToReplaceAuto->containsUnexpandedParameterPack()})
4577 .TransformType(TypeWithAuto);
4578 return SubstituteDeducedTypeTransform(*this, TypeToReplaceAuto)
4579 .TransformType(TypeWithAuto);
4580}
4581
4582TypeSourceInfo *Sema::SubstAutoTypeSourceInfo(TypeSourceInfo *TypeWithAuto,
4583 QualType TypeToReplaceAuto) {
4584 if (TypeToReplaceAuto->isDependentType())
4585 return SubstituteDeducedTypeTransform(
4586 *this,
4587 DependentAuto{
4588 TypeToReplaceAuto->containsUnexpandedParameterPack()})
4589 .TransformType(TypeWithAuto);
4590 return SubstituteDeducedTypeTransform(*this, TypeToReplaceAuto)
4591 .TransformType(TypeWithAuto);
4592}
4593
4594QualType Sema::ReplaceAutoType(QualType TypeWithAuto,
4595 QualType TypeToReplaceAuto) {
4596 return SubstituteDeducedTypeTransform(*this, TypeToReplaceAuto,
4597 /*UseTypeSugar*/ false)
4598 .TransformType(TypeWithAuto);
4599}
4600
4601void Sema::DiagnoseAutoDeductionFailure(VarDecl *VDecl, Expr *Init) {
4602 if (isa<InitListExpr>(Init))
4603 Diag(VDecl->getLocation(),
4604 VDecl->isInitCapture()
4605 ? diag::err_init_capture_deduction_failure_from_init_list
4606 : diag::err_auto_var_deduction_failure_from_init_list)
4607 << VDecl->getDeclName() << VDecl->getType() << Init->getSourceRange();
4608 else
4609 Diag(VDecl->getLocation(),
4610 VDecl->isInitCapture() ? diag::err_init_capture_deduction_failure
4611 : diag::err_auto_var_deduction_failure)
4612 << VDecl->getDeclName() << VDecl->getType() << Init->getType()
4613 << Init->getSourceRange();
4614}
4615
4616bool Sema::DeduceReturnType(FunctionDecl *FD, SourceLocation Loc,
4617 bool Diagnose) {
4618 assert(FD->getReturnType()->isUndeducedType())((FD->getReturnType()->isUndeducedType()) ? static_cast
<void> (0) : __assert_fail ("FD->getReturnType()->isUndeducedType()"
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 4618, __PRETTY_FUNCTION__))
;
4619
4620 // For a lambda's conversion operator, deduce any 'auto' or 'decltype(auto)'
4621 // within the return type from the call operator's type.
4622 if (isLambdaConversionOperator(FD)) {
4623 CXXRecordDecl *Lambda = cast<CXXMethodDecl>(FD)->getParent();
4624 FunctionDecl *CallOp = Lambda->getLambdaCallOperator();
4625
4626 // For a generic lambda, instantiate the call operator if needed.
4627 if (auto *Args = FD->getTemplateSpecializationArgs()) {
4628 CallOp = InstantiateFunctionDeclaration(
4629 CallOp->getDescribedFunctionTemplate(), Args, Loc);
4630 if (!CallOp || CallOp->isInvalidDecl())
4631 return true;
4632
4633 // We might need to deduce the return type by instantiating the definition
4634 // of the operator() function.
4635 if (CallOp->getReturnType()->isUndeducedType())
4636 InstantiateFunctionDefinition(Loc, CallOp);
4637 }
4638
4639 if (CallOp->isInvalidDecl())
4640 return true;
4641 assert(!CallOp->getReturnType()->isUndeducedType() &&((!CallOp->getReturnType()->isUndeducedType() &&
"failed to deduce lambda return type") ? static_cast<void
> (0) : __assert_fail ("!CallOp->getReturnType()->isUndeducedType() && \"failed to deduce lambda return type\""
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 4642, __PRETTY_FUNCTION__))
4642 "failed to deduce lambda return type")((!CallOp->getReturnType()->isUndeducedType() &&
"failed to deduce lambda return type") ? static_cast<void
> (0) : __assert_fail ("!CallOp->getReturnType()->isUndeducedType() && \"failed to deduce lambda return type\""
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 4642, __PRETTY_FUNCTION__))
;
4643
4644 // Build the new return type from scratch.
4645 QualType RetType = getLambdaConversionFunctionResultType(
4646 CallOp->getType()->castAs<FunctionProtoType>());
4647 if (FD->getReturnType()->getAs<PointerType>())
4648 RetType = Context.getPointerType(RetType);
4649 else {
4650 assert(FD->getReturnType()->getAs<BlockPointerType>())((FD->getReturnType()->getAs<BlockPointerType>())
? static_cast<void> (0) : __assert_fail ("FD->getReturnType()->getAs<BlockPointerType>()"
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 4650, __PRETTY_FUNCTION__))
;
4651 RetType = Context.getBlockPointerType(RetType);
4652 }
4653 Context.adjustDeducedFunctionResultType(FD, RetType);
4654 return false;
4655 }
4656
4657 if (FD->getTemplateInstantiationPattern())
4658 InstantiateFunctionDefinition(Loc, FD);
4659
4660 bool StillUndeduced = FD->getReturnType()->isUndeducedType();
4661 if (StillUndeduced && Diagnose && !FD->isInvalidDecl()) {
4662 Diag(Loc, diag::err_auto_fn_used_before_defined) << FD;
4663 Diag(FD->getLocation(), diag::note_callee_decl) << FD;
4664 }
4665
4666 return StillUndeduced;
4667}
4668
4669/// If this is a non-static member function,
4670static void
4671AddImplicitObjectParameterType(ASTContext &Context,
4672 CXXMethodDecl *Method,
4673 SmallVectorImpl<QualType> &ArgTypes) {
4674 // C++11 [temp.func.order]p3:
4675 // [...] The new parameter is of type "reference to cv A," where cv are
4676 // the cv-qualifiers of the function template (if any) and A is
4677 // the class of which the function template is a member.
4678 //
4679 // The standard doesn't say explicitly, but we pick the appropriate kind of
4680 // reference type based on [over.match.funcs]p4.
4681 QualType ArgTy = Context.getTypeDeclType(Method->getParent());
4682 ArgTy = Context.getQualifiedType(ArgTy, Method->getMethodQualifiers());
4683 if (Method->getRefQualifier() == RQ_RValue)
4684 ArgTy = Context.getRValueReferenceType(ArgTy);
4685 else
4686 ArgTy = Context.getLValueReferenceType(ArgTy);
4687 ArgTypes.push_back(ArgTy);
4688}
4689
4690/// Determine whether the function template \p FT1 is at least as
4691/// specialized as \p FT2.
4692static bool isAtLeastAsSpecializedAs(Sema &S,
4693 SourceLocation Loc,
4694 FunctionTemplateDecl *FT1,
4695 FunctionTemplateDecl *FT2,
4696 TemplatePartialOrderingContext TPOC,
4697 unsigned NumCallArguments1) {
4698 FunctionDecl *FD1 = FT1->getTemplatedDecl();
4699 FunctionDecl *FD2 = FT2->getTemplatedDecl();
4700 const FunctionProtoType *Proto1 = FD1->getType()->getAs<FunctionProtoType>();
4701 const FunctionProtoType *Proto2 = FD2->getType()->getAs<FunctionProtoType>();
4702
4703 assert(Proto1 && Proto2 && "Function templates must have prototypes")((Proto1 && Proto2 && "Function templates must have prototypes"
) ? static_cast<void> (0) : __assert_fail ("Proto1 && Proto2 && \"Function templates must have prototypes\""
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 4703, __PRETTY_FUNCTION__))
;
4704 TemplateParameterList *TemplateParams = FT2->getTemplateParameters();
4705 SmallVector<DeducedTemplateArgument, 4> Deduced;
4706 Deduced.resize(TemplateParams->size());
4707
4708 // C++0x [temp.deduct.partial]p3:
4709 // The types used to determine the ordering depend on the context in which
4710 // the partial ordering is done:
4711 TemplateDeductionInfo Info(Loc);
4712 SmallVector<QualType, 4> Args2;
4713 switch (TPOC) {
4714 case TPOC_Call: {
4715 // - In the context of a function call, the function parameter types are
4716 // used.
4717 CXXMethodDecl *Method1 = dyn_cast<CXXMethodDecl>(FD1);
4718 CXXMethodDecl *Method2 = dyn_cast<CXXMethodDecl>(FD2);
4719
4720 // C++11 [temp.func.order]p3:
4721 // [...] If only one of the function templates is a non-static
4722 // member, that function template is considered to have a new
4723 // first parameter inserted in its function parameter list. The
4724 // new parameter is of type "reference to cv A," where cv are
4725 // the cv-qualifiers of the function template (if any) and A is
4726 // the class of which the function template is a member.
4727 //
4728 // Note that we interpret this to mean "if one of the function
4729 // templates is a non-static member and the other is a non-member";
4730 // otherwise, the ordering rules for static functions against non-static
4731 // functions don't make any sense.
4732 //
4733 // C++98/03 doesn't have this provision but we've extended DR532 to cover
4734 // it as wording was broken prior to it.
4735 SmallVector<QualType, 4> Args1;
4736
4737 unsigned NumComparedArguments = NumCallArguments1;
4738
4739 if (!Method2 && Method1 && !Method1->isStatic()) {
4740 // Compare 'this' from Method1 against first parameter from Method2.
4741 AddImplicitObjectParameterType(S.Context, Method1, Args1);
4742 ++NumComparedArguments;
4743 } else if (!Method1 && Method2 && !Method2->isStatic()) {
4744 // Compare 'this' from Method2 against first parameter from Method1.
4745 AddImplicitObjectParameterType(S.Context, Method2, Args2);
4746 }
4747
4748 Args1.insert(Args1.end(), Proto1->param_type_begin(),
4749 Proto1->param_type_end());
4750 Args2.insert(Args2.end(), Proto2->param_type_begin(),
4751 Proto2->param_type_end());
4752
4753 // C++ [temp.func.order]p5:
4754 // The presence of unused ellipsis and default arguments has no effect on
4755 // the partial ordering of function templates.
4756 if (Args1.size() > NumComparedArguments)
4757 Args1.resize(NumComparedArguments);
4758 if (Args2.size() > NumComparedArguments)
4759 Args2.resize(NumComparedArguments);
4760 if (DeduceTemplateArguments(S, TemplateParams, Args2.data(), Args2.size(),
4761 Args1.data(), Args1.size(), Info, Deduced,
4762 TDF_None, /*PartialOrdering=*/true))
4763 return false;
4764
4765 break;
4766 }
4767
4768 case TPOC_Conversion:
4769 // - In the context of a call to a conversion operator, the return types
4770 // of the conversion function templates are used.
4771 if (DeduceTemplateArgumentsByTypeMatch(
4772 S, TemplateParams, Proto2->getReturnType(), Proto1->getReturnType(),
4773 Info, Deduced, TDF_None,
4774 /*PartialOrdering=*/true))
4775 return false;
4776 break;
4777
4778 case TPOC_Other:
4779 // - In other contexts (14.6.6.2) the function template's function type
4780 // is used.
4781 if (DeduceTemplateArgumentsByTypeMatch(S, TemplateParams,
4782 FD2->getType(), FD1->getType(),
4783 Info, Deduced, TDF_None,
4784 /*PartialOrdering=*/true))
4785 return false;
4786 break;
4787 }
4788
4789 // C++0x [temp.deduct.partial]p11:
4790 // In most cases, all template parameters must have values in order for
4791 // deduction to succeed, but for partial ordering purposes a template
4792 // parameter may remain without a value provided it is not used in the
4793 // types being used for partial ordering. [ Note: a template parameter used
4794 // in a non-deduced context is considered used. -end note]
4795 unsigned ArgIdx = 0, NumArgs = Deduced.size();
4796 for (; ArgIdx != NumArgs; ++ArgIdx)
4797 if (Deduced[ArgIdx].isNull())
4798 break;
4799
4800 // FIXME: We fail to implement [temp.deduct.type]p1 along this path. We need
4801 // to substitute the deduced arguments back into the template and check that
4802 // we get the right type.
4803
4804 if (ArgIdx == NumArgs) {
4805 // All template arguments were deduced. FT1 is at least as specialized
4806 // as FT2.
4807 return true;
4808 }
4809
4810 // Figure out which template parameters were used.
4811 llvm::SmallBitVector UsedParameters(TemplateParams->size());
4812 switch (TPOC) {
4813 case TPOC_Call:
4814 for (unsigned I = 0, N = Args2.size(); I != N; ++I)
4815 ::MarkUsedTemplateParameters(S.Context, Args2[I], false,
4816 TemplateParams->getDepth(),
4817 UsedParameters);
4818 break;
4819
4820 case TPOC_Conversion:
4821 ::MarkUsedTemplateParameters(S.Context, Proto2->getReturnType(), false,
4822 TemplateParams->getDepth(), UsedParameters);
4823 break;
4824
4825 case TPOC_Other:
4826 ::MarkUsedTemplateParameters(S.Context, FD2->getType(), false,
4827 TemplateParams->getDepth(),
4828 UsedParameters);
4829 break;
4830 }
4831
4832 for (; ArgIdx != NumArgs; ++ArgIdx)
4833 // If this argument had no value deduced but was used in one of the types
4834 // used for partial ordering, then deduction fails.
4835 if (Deduced[ArgIdx].isNull() && UsedParameters[ArgIdx])
4836 return false;
4837
4838 return true;
4839}
4840
4841/// Determine whether this a function template whose parameter-type-list
4842/// ends with a function parameter pack.
4843static bool isVariadicFunctionTemplate(FunctionTemplateDecl *FunTmpl) {
4844 FunctionDecl *Function = FunTmpl->getTemplatedDecl();
4845 unsigned NumParams = Function->getNumParams();
4846 if (NumParams == 0)
4847 return false;
4848
4849 ParmVarDecl *Last = Function->getParamDecl(NumParams - 1);
4850 if (!Last->isParameterPack())
4851 return false;
4852
4853 // Make sure that no previous parameter is a parameter pack.
4854 while (--NumParams > 0) {
4855 if (Function->getParamDecl(NumParams - 1)->isParameterPack())
4856 return false;
4857 }
4858
4859 return true;
4860}
4861
4862/// Returns the more specialized function template according
4863/// to the rules of function template partial ordering (C++ [temp.func.order]).
4864///
4865/// \param FT1 the first function template
4866///
4867/// \param FT2 the second function template
4868///
4869/// \param TPOC the context in which we are performing partial ordering of
4870/// function templates.
4871///
4872/// \param NumCallArguments1 The number of arguments in the call to FT1, used
4873/// only when \c TPOC is \c TPOC_Call.
4874///
4875/// \param NumCallArguments2 The number of arguments in the call to FT2, used
4876/// only when \c TPOC is \c TPOC_Call.
4877///
4878/// \returns the more specialized function template. If neither
4879/// template is more specialized, returns NULL.
4880FunctionTemplateDecl *
4881Sema::getMoreSpecializedTemplate(FunctionTemplateDecl *FT1,
4882 FunctionTemplateDecl *FT2,
4883 SourceLocation Loc,
4884 TemplatePartialOrderingContext TPOC,
4885 unsigned NumCallArguments1,
4886 unsigned NumCallArguments2) {
4887 bool Better1 = isAtLeastAsSpecializedAs(*this, Loc, FT1, FT2, TPOC,
4888 NumCallArguments1);
4889 bool Better2 = isAtLeastAsSpecializedAs(*this, Loc, FT2, FT1, TPOC,
4890 NumCallArguments2);
4891
4892 if (Better1 != Better2) // We have a clear winner
4893 return Better1 ? FT1 : FT2;
4894
4895 if (!Better1 && !Better2) // Neither is better than the other
4896 return nullptr;
4897
4898 // FIXME: This mimics what GCC implements, but doesn't match up with the
4899 // proposed resolution for core issue 692. This area needs to be sorted out,
4900 // but for now we attempt to maintain compatibility.
4901 bool Variadic1 = isVariadicFunctionTemplate(FT1);
4902 bool Variadic2 = isVariadicFunctionTemplate(FT2);
4903 if (Variadic1 != Variadic2)
4904 return Variadic1? FT2 : FT1;
4905
4906 return nullptr;
4907}
4908
4909/// Determine if the two templates are equivalent.
4910static bool isSameTemplate(TemplateDecl *T1, TemplateDecl *T2) {
4911 if (T1 == T2)
4912 return true;
4913
4914 if (!T1 || !T2)
4915 return false;
4916
4917 return T1->getCanonicalDecl() == T2->getCanonicalDecl();
4918}
4919
4920/// Retrieve the most specialized of the given function template
4921/// specializations.
4922///
4923/// \param SpecBegin the start iterator of the function template
4924/// specializations that we will be comparing.
4925///
4926/// \param SpecEnd the end iterator of the function template
4927/// specializations, paired with \p SpecBegin.
4928///
4929/// \param Loc the location where the ambiguity or no-specializations
4930/// diagnostic should occur.
4931///
4932/// \param NoneDiag partial diagnostic used to diagnose cases where there are
4933/// no matching candidates.
4934///
4935/// \param AmbigDiag partial diagnostic used to diagnose an ambiguity, if one
4936/// occurs.
4937///
4938/// \param CandidateDiag partial diagnostic used for each function template
4939/// specialization that is a candidate in the ambiguous ordering. One parameter
4940/// in this diagnostic should be unbound, which will correspond to the string
4941/// describing the template arguments for the function template specialization.
4942///
4943/// \returns the most specialized function template specialization, if
4944/// found. Otherwise, returns SpecEnd.
4945UnresolvedSetIterator Sema::getMostSpecialized(
4946 UnresolvedSetIterator SpecBegin, UnresolvedSetIterator SpecEnd,
4947 TemplateSpecCandidateSet &FailedCandidates,
4948 SourceLocation Loc, const PartialDiagnostic &NoneDiag,
4949 const PartialDiagnostic &AmbigDiag, const PartialDiagnostic &CandidateDiag,
4950 bool Complain, QualType TargetType) {
4951 if (SpecBegin == SpecEnd) {
4952 if (Complain) {
4953 Diag(Loc, NoneDiag);
4954 FailedCandidates.NoteCandidates(*this, Loc);
4955 }
4956 return SpecEnd;
4957 }
4958
4959 if (SpecBegin + 1 == SpecEnd)
4960 return SpecBegin;
4961
4962 // Find the function template that is better than all of the templates it
4963 // has been compared to.
4964 UnresolvedSetIterator Best = SpecBegin;
4965 FunctionTemplateDecl *BestTemplate
4966 = cast<FunctionDecl>(*Best)->getPrimaryTemplate();
4967 assert(BestTemplate && "Not a function template specialization?")((BestTemplate && "Not a function template specialization?"
) ? static_cast<void> (0) : __assert_fail ("BestTemplate && \"Not a function template specialization?\""
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 4967, __PRETTY_FUNCTION__))
;
4968 for (UnresolvedSetIterator I = SpecBegin + 1; I != SpecEnd; ++I) {
4969 FunctionTemplateDecl *Challenger
4970 = cast<FunctionDecl>(*I)->getPrimaryTemplate();
4971 assert(Challenger && "Not a function template specialization?")((Challenger && "Not a function template specialization?"
) ? static_cast<void> (0) : __assert_fail ("Challenger && \"Not a function template specialization?\""
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 4971, __PRETTY_FUNCTION__))
;
4972 if (isSameTemplate(getMoreSpecializedTemplate(BestTemplate, Challenger,
4973 Loc, TPOC_Other, 0, 0),
4974 Challenger)) {
4975 Best = I;
4976 BestTemplate = Challenger;
4977 }
4978 }
4979
4980 // Make sure that the "best" function template is more specialized than all
4981 // of the others.
4982 bool Ambiguous = false;
4983 for (UnresolvedSetIterator I = SpecBegin; I != SpecEnd; ++I) {
4984 FunctionTemplateDecl *Challenger
4985 = cast<FunctionDecl>(*I)->getPrimaryTemplate();
4986 if (I != Best &&
4987 !isSameTemplate(getMoreSpecializedTemplate(BestTemplate, Challenger,
4988 Loc, TPOC_Other, 0, 0),
4989 BestTemplate)) {
4990 Ambiguous = true;
4991 break;
4992 }
4993 }
4994
4995 if (!Ambiguous) {
4996 // We found an answer. Return it.
4997 return Best;
4998 }
4999
5000 // Diagnose the ambiguity.
5001 if (Complain) {
5002 Diag(Loc, AmbigDiag);
5003
5004 // FIXME: Can we order the candidates in some sane way?
5005 for (UnresolvedSetIterator I = SpecBegin; I != SpecEnd; ++I) {
5006 PartialDiagnostic PD = CandidateDiag;
5007 const auto *FD = cast<FunctionDecl>(*I);
5008 PD << FD << getTemplateArgumentBindingsText(
5009 FD->getPrimaryTemplate()->getTemplateParameters(),
5010 *FD->getTemplateSpecializationArgs());
5011 if (!TargetType.isNull())
5012 HandleFunctionTypeMismatch(PD, FD->getType(), TargetType);
5013 Diag((*I)->getLocation(), PD);
5014 }
5015 }
5016
5017 return SpecEnd;
5018}
5019
5020/// Determine whether one partial specialization, P1, is at least as
5021/// specialized than another, P2.
5022///
5023/// \tparam TemplateLikeDecl The kind of P2, which must be a
5024/// TemplateDecl or {Class,Var}TemplatePartialSpecializationDecl.
5025/// \param T1 The injected-class-name of P1 (faked for a variable template).
5026/// \param T2 The injected-class-name of P2 (faked for a variable template).
5027template<typename TemplateLikeDecl>
5028static bool isAtLeastAsSpecializedAs(Sema &S, QualType T1, QualType T2,
5029 TemplateLikeDecl *P2,
5030 TemplateDeductionInfo &Info) {
5031 // C++ [temp.class.order]p1:
5032 // For two class template partial specializations, the first is at least as
5033 // specialized as the second if, given the following rewrite to two
5034 // function templates, the first function template is at least as
5035 // specialized as the second according to the ordering rules for function
5036 // templates (14.6.6.2):
5037 // - the first function template has the same template parameters as the
5038 // first partial specialization and has a single function parameter
5039 // whose type is a class template specialization with the template
5040 // arguments of the first partial specialization, and
5041 // - the second function template has the same template parameters as the
5042 // second partial specialization and has a single function parameter
5043 // whose type is a class template specialization with the template
5044 // arguments of the second partial specialization.
5045 //
5046 // Rather than synthesize function templates, we merely perform the
5047 // equivalent partial ordering by performing deduction directly on
5048 // the template arguments of the class template partial
5049 // specializations. This computation is slightly simpler than the
5050 // general problem of function template partial ordering, because
5051 // class template partial specializations are more constrained. We
5052 // know that every template parameter is deducible from the class
5053 // template partial specialization's template arguments, for
5054 // example.
5055 SmallVector<DeducedTemplateArgument, 4> Deduced;
5056
5057 // Determine whether P1 is at least as specialized as P2.
5058 Deduced.resize(P2->getTemplateParameters()->size());
5059 if (DeduceTemplateArgumentsByTypeMatch(S, P2->getTemplateParameters(),
5060 T2, T1, Info, Deduced, TDF_None,
5061 /*PartialOrdering=*/true))
5062 return false;
5063
5064 SmallVector<TemplateArgument, 4> DeducedArgs(Deduced.begin(),
5065 Deduced.end());
5066 Sema::InstantiatingTemplate Inst(S, Info.getLocation(), P2, DeducedArgs,
5067 Info);
5068 auto *TST1 = T1->castAs<TemplateSpecializationType>();
5069 if (FinishTemplateArgumentDeduction(
5070 S, P2, /*PartialOrdering=*/true,
5071 TemplateArgumentList(TemplateArgumentList::OnStack,
5072 TST1->template_arguments()),
5073 Deduced, Info))
5074 return false;
5075
5076 return true;
5077}
5078
5079/// Returns the more specialized class template partial specialization
5080/// according to the rules of partial ordering of class template partial
5081/// specializations (C++ [temp.class.order]).
5082///
5083/// \param PS1 the first class template partial specialization
5084///
5085/// \param PS2 the second class template partial specialization
5086///
5087/// \returns the more specialized class template partial specialization. If
5088/// neither partial specialization is more specialized, returns NULL.
5089ClassTemplatePartialSpecializationDecl *
5090Sema::getMoreSpecializedPartialSpecialization(
5091 ClassTemplatePartialSpecializationDecl *PS1,
5092 ClassTemplatePartialSpecializationDecl *PS2,
5093 SourceLocation Loc) {
5094 QualType PT1 = PS1->getInjectedSpecializationType();
5095 QualType PT2 = PS2->getInjectedSpecializationType();
5096
5097 TemplateDeductionInfo Info(Loc);
5098 bool Better1 = isAtLeastAsSpecializedAs(*this, PT1, PT2, PS2, Info);
5099 bool Better2 = isAtLeastAsSpecializedAs(*this, PT2, PT1, PS1, Info);
5100
5101 if (Better1 == Better2)
5102 return nullptr;
5103
5104 return Better1 ? PS1 : PS2;
5105}
5106
5107bool Sema::isMoreSpecializedThanPrimary(
5108 ClassTemplatePartialSpecializationDecl *Spec, TemplateDeductionInfo &Info) {
5109 ClassTemplateDecl *Primary = Spec->getSpecializedTemplate();
5110 QualType PrimaryT = Primary->getInjectedClassNameSpecialization();
5111 QualType PartialT = Spec->getInjectedSpecializationType();
5112 if (!isAtLeastAsSpecializedAs(*this, PartialT, PrimaryT, Primary, Info))
5113 return false;
5114 if (isAtLeastAsSpecializedAs(*this, PrimaryT, PartialT, Spec, Info)) {
5115 Info.clearSFINAEDiagnostic();
5116 return false;
5117 }
5118 return true;
5119}
5120
5121VarTemplatePartialSpecializationDecl *
5122Sema::getMoreSpecializedPartialSpecialization(
5123 VarTemplatePartialSpecializationDecl *PS1,
5124 VarTemplatePartialSpecializationDecl *PS2, SourceLocation Loc) {
5125 // Pretend the variable template specializations are class template
5126 // specializations and form a fake injected class name type for comparison.
5127 assert(PS1->getSpecializedTemplate() == PS2->getSpecializedTemplate() &&((PS1->getSpecializedTemplate() == PS2->getSpecializedTemplate
() && "the partial specializations being compared should specialize"
" the same template.") ? static_cast<void> (0) : __assert_fail
("PS1->getSpecializedTemplate() == PS2->getSpecializedTemplate() && \"the partial specializations being compared should specialize\" \" the same template.\""
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 5129, __PRETTY_FUNCTION__))
5128 "the partial specializations being compared should specialize"((PS1->getSpecializedTemplate() == PS2->getSpecializedTemplate
() && "the partial specializations being compared should specialize"
" the same template.") ? static_cast<void> (0) : __assert_fail
("PS1->getSpecializedTemplate() == PS2->getSpecializedTemplate() && \"the partial specializations being compared should specialize\" \" the same template.\""
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 5129, __PRETTY_FUNCTION__))
5129 " the same template.")((PS1->getSpecializedTemplate() == PS2->getSpecializedTemplate
() && "the partial specializations being compared should specialize"
" the same template.") ? static_cast<void> (0) : __assert_fail
("PS1->getSpecializedTemplate() == PS2->getSpecializedTemplate() && \"the partial specializations being compared should specialize\" \" the same template.\""
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 5129, __PRETTY_FUNCTION__))
;
5130 TemplateName Name(PS1->getSpecializedTemplate());
5131 TemplateName CanonTemplate = Context.getCanonicalTemplateName(Name);
5132 QualType PT1 = Context.getTemplateSpecializationType(
5133 CanonTemplate, PS1->getTemplateArgs().asArray());
5134 QualType PT2 = Context.getTemplateSpecializationType(
5135 CanonTemplate, PS2->getTemplateArgs().asArray());
5136
5137 TemplateDeductionInfo Info(Loc);
5138 bool Better1 = isAtLeastAsSpecializedAs(*this, PT1, PT2, PS2, Info);
5139 bool Better2 = isAtLeastAsSpecializedAs(*this, PT2, PT1, PS1, Info);
5140
5141 if (Better1 == Better2)
5142 return nullptr;
5143
5144 return Better1 ? PS1 : PS2;
5145}
5146
5147bool Sema::isMoreSpecializedThanPrimary(
5148 VarTemplatePartialSpecializationDecl *Spec, TemplateDeductionInfo &Info) {
5149 TemplateDecl *Primary = Spec->getSpecializedTemplate();
5150 // FIXME: Cache the injected template arguments rather than recomputing
5151 // them for each partial specialization.
5152 SmallVector<TemplateArgument, 8> PrimaryArgs;
5153 Context.getInjectedTemplateArgs(Primary->getTemplateParameters(),
5154 PrimaryArgs);
5155
5156 TemplateName CanonTemplate =
5157 Context.getCanonicalTemplateName(TemplateName(Primary));
5158 QualType PrimaryT = Context.getTemplateSpecializationType(
5159 CanonTemplate, PrimaryArgs);
5160 QualType PartialT = Context.getTemplateSpecializationType(
5161 CanonTemplate, Spec->getTemplateArgs().asArray());
5162 if (!isAtLeastAsSpecializedAs(*this, PartialT, PrimaryT, Primary, Info))
5163 return false;
5164 if (isAtLeastAsSpecializedAs(*this, PrimaryT, PartialT, Spec, Info)) {
5165 Info.clearSFINAEDiagnostic();
5166 return false;
5167 }
5168 return true;
5169}
5170
5171bool Sema::isTemplateTemplateParameterAtLeastAsSpecializedAs(
5172 TemplateParameterList *P, TemplateDecl *AArg, SourceLocation Loc) {
5173 // C++1z [temp.arg.template]p4: (DR 150)
5174 // A template template-parameter P is at least as specialized as a
5175 // template template-argument A if, given the following rewrite to two
5176 // function templates...
5177
5178 // Rather than synthesize function templates, we merely perform the
5179 // equivalent partial ordering by performing deduction directly on
5180 // the template parameter lists of the template template parameters.
5181 //
5182 // Given an invented class template X with the template parameter list of
5183 // A (including default arguments):
5184 TemplateName X = Context.getCanonicalTemplateName(TemplateName(AArg));
5185 TemplateParameterList *A = AArg->getTemplateParameters();
5186
5187 // - Each function template has a single function parameter whose type is
5188 // a specialization of X with template arguments corresponding to the
5189 // template parameters from the respective function template
5190 SmallVector<TemplateArgument, 8> AArgs;
5191 Context.getInjectedTemplateArgs(A, AArgs);
5192
5193 // Check P's arguments against A's parameter list. This will fill in default
5194 // template arguments as needed. AArgs are already correct by construction.
5195 // We can't just use CheckTemplateIdType because that will expand alias
5196 // templates.
5197 SmallVector<TemplateArgument, 4> PArgs;
5198 {
5199 SFINAETrap Trap(*this);
5200
5201 Context.getInjectedTemplateArgs(P, PArgs);
5202 TemplateArgumentListInfo PArgList(P->getLAngleLoc(), P->getRAngleLoc());
5203 for (unsigned I = 0, N = P->size(); I != N; ++I) {
5204 // Unwrap packs that getInjectedTemplateArgs wrapped around pack
5205 // expansions, to form an "as written" argument list.
5206 TemplateArgument Arg = PArgs[I];
5207 if (Arg.getKind() == TemplateArgument::Pack) {
5208 assert(Arg.pack_size() == 1 && Arg.pack_begin()->isPackExpansion())((Arg.pack_size() == 1 && Arg.pack_begin()->isPackExpansion
()) ? static_cast<void> (0) : __assert_fail ("Arg.pack_size() == 1 && Arg.pack_begin()->isPackExpansion()"
, "/build/llvm-toolchain-snapshot-9~svn362543/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 5208, __PRETTY_FUNCTION__))
;
5209 Arg = *Arg.pack_begin();
5210 }
5211 PArgList.addArgument(getTrivialTemplateArgumentLoc(
5212 Arg, QualType(), P->getParam(I)->getLocation()));
5213 }
5214 PArgs.clear();
5215
5216 // C++1z [temp.arg.template]p3:
5217 // If the rewrite produces an invalid type, then P is not at least as
5218 // specialized as A.
5219 if (CheckTemplateArgumentList(AArg, Loc, PArgList, false, PArgs) ||
5220 Trap.hasErrorOccurred())
5221 return false;
5222 }
5223
5224 QualType AType = Context.getTemplateSpecializationType(X, AArgs);
5225 QualType PType = Context.getTemplateSpecializationType(X, PArgs);
5226
5227 // ... the function template corresponding to P is at least as specialized
5228 // as the function template corresponding to A according to the partial
5229 // ordering rules for function templates.
5230 TemplateDeductionInfo Info(Loc, A->getDepth());
5231 return isAtLeastAsSpecializedAs(*this, PType, AType, AArg, Info);
5232}
5233
5234/// Mark the template parameters that are used by the given
5235/// expression.
5236static void
5237MarkUsedTemplateParameters(ASTContext &Ctx,
5238 const Expr *E,
5239 bool OnlyDeduced,
5240 unsigned Depth,
5241 llvm::SmallBitVector &Used) {
5242 // We can deduce from a pack expansion.
5243 if (const PackExpansionExpr *Expansion = dyn_cast<PackExpansionExpr>(E))
5244 E = Expansion->getPattern();
5245
5246 // Skip through any implicit casts we added while type-checking, and any
5247 // substitutions performed by template alias expansion.
5248 while (true) {
5249 if (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E))
5250 E = ICE->getSubExpr();
5251 else if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(E))
5252 E = CE->getSubExpr();
5253 else if (const SubstNonTypeTemplateParmExpr *Subst =
5254 dyn_cast<SubstNonTypeTemplateParmExpr>(E))
5255 E = Subst->getReplacement();
5256 else
5257 break;
5258 }
5259
5260 // FIXME: if !OnlyDeduced, we have to walk the whole subexpression to
5261 // find other occurrences of template parameters.
5262 const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E);
5263 if (!DRE)
5264 return;
5265
5266 const NonTypeTemplateParmDecl *NTTP
5267 = dyn_cast<NonTypeTemplateParmDecl>(DRE->getDecl());
5268 if (!NTTP)
5269 return;
5270
5271 if (NTTP->getDepth() == Depth)
5272 Used[NTTP->getIndex()] = true;
5273
5274 // In C++17 mode, additional arguments may be deduced from the type of a
5275 // non-type argument.
5276 if (Ctx.getLangOpts().CPlusPlus17)
5277 MarkUsedTemplateParameters(Ctx, NTTP->getType(), OnlyDeduced, Depth, Used);
5278}
5279
5280/// Mark the template parameters that are used by the given
5281/// nested name specifier.
5282static void
5283MarkUsedTemplateParameters(ASTContext &Ctx,
5284 NestedNameSpecifier *NNS,
5285 bool OnlyDeduced,
5286 unsigned Depth,
5287 llvm::SmallBitVector &Used) {
5288 if (!NNS)
5289 return;
5290
5291 MarkUsedTemplateParameters(Ctx, NNS->getPrefix(), OnlyDeduced, Depth,
5292 Used);
5293 MarkUsedTemplateParameters(Ctx, QualType(NNS->getAsType(), 0),
5294 OnlyDeduced, Depth, Used);
5295}
5296
5297/// Mark the template parameters that are used by the given
5298/// template name.
5299static void
5300MarkUsedTemplateParameters(ASTContext &Ctx,
5301 TemplateName Name,
5302 bool OnlyDeduced,
5303 unsigned Depth,
5304 llvm::SmallBitVector &Used) {
5305 if (TemplateDecl *Template = Name.getAsTemplateDecl()) {
5306 if (TemplateTemplateParmDecl *TTP
5307 = dyn_cast<TemplateTemplateParmDecl>(Template)) {
5308 if (TTP->getDepth() == Depth)
5309 Used[TTP->getIndex()] = true;
5310 }
5311 return;
5312 }
5313
5314 if (QualifiedTemplateName *QTN = Name.getAsQualifiedTemplateName())
5315 MarkUsedTemplateParameters(Ctx, QTN->getQualifier(), OnlyDeduced,
5316 Depth, Used);
5317 if (DependentTemplateName *DTN = Name.getAsDependentTemplateName())
5318 MarkUsedTemplateParameters(Ctx, DTN->getQualifier(), OnlyDeduced,
5319 Depth, Used);
5320}
5321
5322/// Mark the template parameters that are used by the given
5323/// type.
5324static void
5325MarkUsedTemplateParameters(ASTContext &Ctx, QualType T,
5326 bool OnlyDeduced,
5327 unsigned Depth,
5328 llvm::SmallBitVector &Used) {
5329 if (T.isNull())
5330 return;
5331
5332 // Non-dependent types have nothing deducible
5333 if (!T->isDependentType())
5334 return;
5335
5336 T = Ctx.getCanonicalType(T);
5337 switch (T->getTypeClass()) {
5338 case Type::Pointer:
5339 MarkUsedTemplateParameters(Ctx,
5340 cast<PointerType>(T)->getPointeeType(),
5341 OnlyDeduced,
5342 Depth,
5343 Used);
5344 break;
5345
5346 case Type::BlockPointer:
5347 MarkUsedTemplateParameters(Ctx,
5348 cast<BlockPointerType>(T)->getPointeeType(),
5349 OnlyDeduced,
5350 Depth,
5351 Used);
5352 break;
5353
5354 case Type::LValueReference:
5355 case Type::RValueReference:
5356 MarkUsedTemplateParameters(Ctx,
5357 cast<ReferenceType>(T)->getPointeeType(),
5358 OnlyDeduced,
5359 Depth,
5360 Used);
5361 break;
5362
5363 case Type::MemberPointer: {
5364 const MemberPointerType *MemPtr = cast<MemberPointerType>(T.getTypePtr());
5365 MarkUsedTemplateParameters(Ctx, MemPtr->getPointeeType(), OnlyDeduced,
5366 Depth, Used);
5367 MarkUsedTemplateParameters(Ctx, QualType(MemPtr->getClass(), 0),
5368 OnlyDeduced, Depth, Used);
5369 break;
5370 }
5371
5372 case Type::DependentSizedArray:
5373 MarkUsedTemplateParameters(Ctx,
5374 cast<DependentSizedArrayType>(T)->getSizeExpr(),
5375 OnlyDeduced, Depth, Used);
5376 // Fall through to check the element type
5377 LLVM_FALLTHROUGH[[clang::fallthrough]];
5378
5379 case Type::ConstantArray:
5380 case Type::IncompleteArray:
5381 MarkUsedTemplateParameters(Ctx,
5382 cast<ArrayType>(T)->getElementType(),
5383 OnlyDeduced, Depth, Used);
5384 break;
5385
5386 case Type::Vector:
5387 case Type::ExtVector:
5388 MarkUsedTemplateParameters(Ctx,
5389 cast<VectorType>(T)->getElementType(),
5390 OnlyDeduced, Depth, Used);
5391 break;
5392
5393 case Type::DependentVector: {
5394 const auto *VecType = cast<DependentVectorType>(T);
5395 MarkUsedTemplateParameters(Ctx, VecType->getElementType(), OnlyDeduced,
5396 Depth, Used);
5397 MarkUsedTemplateParameters(Ctx, VecType->getSizeExpr(), OnlyDeduced, Depth,
5398 Used);
5399 break;
5400 }
5401 case Type::DependentSizedExtVector: {
5402 const DependentSizedExtVectorType *VecType
5403 = cast<DependentSizedExtVectorType>(T);
5404 MarkUsedTemplateParameters(Ctx, VecType->getElementType(), OnlyDeduced,
5405 Depth, Used);
5406 MarkUsedTemplateParameters(Ctx, VecType->getSizeExpr(), OnlyDeduced,
5407 Depth, Used);
5408 break;
5409 }
5410
5411 case Type::DependentAddressSpace: {
5412 const DependentAddressSpaceType *DependentASType =
5413 cast<DependentAddressSpaceType>(T);
5414 MarkUsedTemplateParameters(Ctx, DependentASType->getPointeeType(),
5415 OnlyDeduced, Depth, Used);
5416 MarkUsedTemplateParameters(Ctx,
5417 DependentASType->getAddrSpaceExpr(),
5418 OnlyDeduced, Depth, Used);
5419 break;
5420 }
5421
5422 case Type::FunctionProto: {
5423 const FunctionProtoType *Proto = cast<FunctionProtoType>(T);
5424 MarkUsedTemplateParameters(Ctx, Proto->getReturnType(), OnlyDeduced, Depth,
5425 Used);
5426 for (unsigned I = 0, N = Proto->getNumParams(); I != N; ++I) {
5427 // C++17 [temp.deduct.type]p5:
5428 // The non-deduced contexts are: [...]
5429 // -- A function parameter pack that does not occur at the end of the
5430 // parameter-declaration-list.
5431 if (!OnlyDeduced || I + 1 == N ||
5432 !Proto->getParamType(I)->getAs<PackExpansionType>()) {
5433 MarkUsedTemplateParameters(Ctx, Proto->getParamType(I), OnlyDeduced,
5434 Depth, Used);
5435 } else {
5436 // FIXME: C++17 [temp.deduct.call]p1:
5437 // When a function parameter pack appears in a non-deduced context,
5438 // the type of that pack is never deduced.
5439 //
5440 // We should also track a set of "never deduced" parameters, and
5441 // subtract that from the list of deduced parameters after marking.
5442 }
5443 }
5444 if (auto *E = Proto->getNoexceptExpr())
5445 MarkUsedTemplateParameters(Ctx, E, OnlyDeduced, Depth, Used);
5446 break;
5447 }
5448
5449 case Type::TemplateTypeParm: {
5450 const TemplateTypeParmType *TTP = cast<TemplateTypeParmType>(T);
5451 if (TTP->getDepth() == Depth)
5452 Used[TTP->getIndex()] = true;
5453 break;
5454 }
5455
5456 case Type::SubstTemplateTypeParmPack: {
5457 const SubstTemplateTypeParmPackType *Subst
5458 = cast<SubstTemplateTypeParmPackType>(T);
5459 MarkUsedTemplateParameters(Ctx,
5460 QualType(Subst->getReplacedParameter(), 0),
5461 OnlyDeduced, Depth, Used);
5462 MarkUsedTemplateParameters(Ctx, Subst->getArgumentPack(),
5463 OnlyDeduced, Depth, Used);
5464 break;
5465 }
5466
5467 case Type::InjectedClassName:
5468 T = cast<InjectedClassNameType>(T)->getInjectedSpecializationType();
5469 LLVM_FALLTHROUGH[[clang::fallthrough]];
5470
5471 case Type::TemplateSpecialization: {
5472 const TemplateSpecializationType *Spec
5473 = cast<TemplateSpecializationType>(T);
5474 MarkUsedTemplateParameters(Ctx, Spec->getTemplateName(), OnlyDeduced,
5475 Depth, Used);
5476
5477 // C++0x [temp.deduct.type]p9:
5478 // If the template argument list of P contains a pack expansion that is
5479 // not the last template argument, the entire template argument list is a
5480 // non-deduced context.
5481 if (OnlyDeduced &&
5482 hasPackExpansionBeforeEnd(Spec->template_arguments()))
5483 break;
5484
5485 for (unsigned I = 0, N = Spec->getNumArgs(); I != N; ++I)
5486 MarkUsedTemplateParameters(Ctx, Spec->getArg(I), OnlyDeduced, Depth,
5487 Used);
5488 break;
5489 }
5490
5491 case Type::Complex:
5492 if (!OnlyDeduced)
5493 MarkUsedTemplateParameters(Ctx,
5494 cast<ComplexType>(T)->getElementType(),
5495 OnlyDeduced, Depth, Used);
5496 break;
5497
5498 case Type::Atomic:
5499 if (!OnlyDeduced)
5500 MarkUsedTemplateParameters(Ctx,
5501 cast<AtomicType>(T)->getValueType(),
5502 OnlyDeduced, Depth, Used);
5503 break;
5504
5505 case Type::DependentName:
5506 if (!OnlyDeduced)
5507 MarkUsedTemplateParameters(Ctx,
5508 cast<DependentNameType>(T)->getQualifier(),
5509 OnlyDeduced, Depth, Used);
5510 break;
5511
5512 case Type::DependentTemplateSpecialization: {
5513 // C++14 [temp.deduct.type]p5:
5514 // The non-deduced contexts are:
5515 // -- The nested-name-specifier of a type that was specified using a
5516 // qualified-id
5517 //
5518 // C++14 [temp.deduct.type]p6:
5519 // When a type name is specified in a way that includes a non-deduced
5520 // context, all of the types that comprise that type name are also
5521 // non-deduced.
5522 if (OnlyDeduced)
5523 break;
5524
5525 const DependentTemplateSpecializationType *Spec
5526 = cast<DependentTemplateSpecializationType>(T);
5527
5528 MarkUsedTemplateParameters(Ctx, Spec->getQualifier(),
5529 OnlyDeduced, Depth, Used);
5530
5531 for (unsigned I = 0, N = Spec->getNumArgs(); I != N; ++I)
5532 MarkUsedTemplateParameters(Ctx, Spec->getArg(I), OnlyDeduced, Depth,
5533 Used);
5534 break;
5535 }
5536
5537 case Type::TypeOf:
5538 if (!OnlyDeduced)
5539 MarkUsedTemplateParameters(Ctx,
5540 cast<TypeOfType>(T)->getUnderlyingType(),
5541 OnlyDeduced, Depth, Used);
5542 break;
5543
5544 case Type::TypeOfExpr:
5545 if (!OnlyDeduced)
5546 MarkUsedTemplateParameters(Ctx,
5547 cast<TypeOfExprType>(T)->getUnderlyingExpr(),
5548 OnlyDeduced, Depth, Used);
5549 break;
5550
5551 case Type::Decltype:
5552 if (!OnlyDeduced)
5553 MarkUsedTemplateParameters(Ctx,
5554 cast<DecltypeType>(T)->getUnderlyingExpr(),
5555 OnlyDeduced, Depth, Used);
5556 break;
5557
5558 case Type::UnaryTransform:
5559 if (!OnlyDeduced)
5560 MarkUsedTemplateParameters(Ctx,
5561 cast<UnaryTransformType>(T)->getUnderlyingType(),
5562 OnlyDeduced, Depth, Used);
5563 break;
5564
5565 case Type::PackExpansion:
5566 MarkUsedTemplateParameters(Ctx,
5567 cast<PackExpansionType>(T)->getPattern(),
5568 OnlyDeduced, Depth, Used);
5569 break;
5570
5571 case Type::Auto:
5572 case Type::DeducedTemplateSpecialization:
5573 MarkUsedTemplateParameters(Ctx,
5574 cast<DeducedType>(T)->getDeducedType(),
5575 OnlyDeduced, Depth, Used);
5576 break;
5577
5578 // None of these types have any template parameters in them.
5579 case Type::Builtin:
5580 case Type::VariableArray:
5581 case Type::FunctionNoProto:
5582 case Type::Record:
5583 case Type::Enum:
5584 case Type::ObjCInterface:
5585 case Type::ObjCObject:
5586 case Type::ObjCObjectPointer:
5587 case Type::UnresolvedUsing:
5588 case Type::Pipe:
5589#define TYPE(Class, Base)
5590#define ABSTRACT_TYPE(Class, Base)
5591#define DEPENDENT_TYPE(Class, Base)
5592#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
5593#include "clang/AST/TypeNodes.def"
5594 break;
5595 }
5596}
5597
5598/// Mark the template parameters that are used by this
5599/// template argument.
5600static void
5601MarkUsedTemplateParameters(ASTContext &Ctx,
5602 const TemplateArgument &TemplateArg,
5603 bool OnlyDeduced,
5604 unsigned Depth,
5605 llvm::SmallBitVector &Used) {
5606 switch (TemplateArg.getKind()) {
5607 case TemplateArgument::Null:
5608 case TemplateArgument::Integral:
5609 case TemplateArgument::Declaration:
5610 break;
5611
5612 case TemplateArgument::NullPtr:
5613 MarkUsedTemplateParameters(Ctx, TemplateArg.getNullPtrType(), OnlyDeduced,
5614 Depth, Used);
5615 break;
5616
5617 case TemplateArgument::Type:
5618 MarkUsedTemplateParameters(Ctx, TemplateArg.getAsType(), OnlyDeduced,
5619 Depth, Used);
5620 break;
5621
5622 case TemplateArgument::Template:
5623 case TemplateArgument::TemplateExpansion:
5624 MarkUsedTemplateParameters(Ctx,
5625 TemplateArg.getAsTemplateOrTemplatePattern(),
5626 OnlyDeduced, Depth, Used);
5627 break;
5628
5629 case TemplateArgument::Expression:
5630 MarkUsedTemplateParameters(Ctx, TemplateArg.getAsExpr(), OnlyDeduced,
5631 Depth, Used);
5632 break;
5633
5634 case TemplateArgument::Pack:
5635 for (const auto &P : TemplateArg.pack_elements())
5636 MarkUsedTemplateParameters(Ctx, P, OnlyDeduced, Depth, Used);
5637 break;
5638 }
5639}
5640
5641/// Mark which template parameters can be deduced from a given
5642/// template argument list.
5643///
5644/// \param TemplateArgs the template argument list from which template
5645/// parameters will be deduced.
5646///
5647/// \param Used a bit vector whose elements will be set to \c true
5648/// to indicate when the corresponding template parameter will be
5649/// deduced.
5650void
5651Sema::MarkUsedTemplateParameters(const TemplateArgumentList &TemplateArgs,
5652 bool OnlyDeduced, unsigned Depth,
5653 llvm::SmallBitVector &Used) {
5654 // C++0x [temp.deduct.type]p9:
5655 // If the template argument list of P contains a pack expansion that is not
5656 // the last template argument, the entire template argument list is a
5657 // non-deduced context.
5658 if (OnlyDeduced &&
5659 hasPackExpansionBeforeEnd(TemplateArgs.asArray()))
5660 return;
5661
5662 for (unsigned I = 0, N = TemplateArgs.size(); I != N; ++I)
5663 ::MarkUsedTemplateParameters(Context, TemplateArgs[I], OnlyDeduced,
5664 Depth, Used);
5665}
5666
5667/// Marks all of the template parameters that will be deduced by a
5668/// call to the given function template.
5669void Sema::MarkDeducedTemplateParameters(
5670 ASTContext &Ctx, const FunctionTemplateDecl *FunctionTemplate,
5671 llvm::SmallBitVector &Deduced) {
5672 TemplateParameterList *TemplateParams
5673 = FunctionTemplate->getTemplateParameters();
5674 Deduced.clear();
5675 Deduced.resize(TemplateParams->size());
5676
5677 FunctionDecl *Function = FunctionTemplate->getTemplatedDecl();
5678 for (unsigned I = 0, N = Function->getNumParams(); I != N; ++I)
5679 ::MarkUsedTemplateParameters(Ctx, Function->getParamDecl(I)->getType(),
5680 true, TemplateParams->getDepth(), Deduced);
5681}
5682
5683bool hasDeducibleTemplateParameters(Sema &S,
5684 FunctionTemplateDecl *FunctionTemplate,
5685 QualType T) {
5686 if (!T->isDependentType())
5687 return false;
5688
5689 TemplateParameterList *TemplateParams
5690 = FunctionTemplate->getTemplateParameters();
5691 llvm::SmallBitVector Deduced(TemplateParams->size());
5692 ::MarkUsedTemplateParameters(S.Context, T, true, TemplateParams->getDepth(),
5693 Deduced);
5694
5695 return Deduced.any();
5696}

/build/llvm-toolchain-snapshot-9~svn362543/include/llvm/ADT/SmallBitVector.h

1//===- llvm/ADT/SmallBitVector.h - 'Normally small' bit vectors -*- 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// This file implements the SmallBitVector class.
10//
11//===----------------------------------------------------------------------===//
12
13#ifndef LLVM_ADT_SMALLBITVECTOR_H
14#define LLVM_ADT_SMALLBITVECTOR_H
15
16#include "llvm/ADT/BitVector.h"
17#include "llvm/ADT/iterator_range.h"
18#include "llvm/Support/MathExtras.h"
19#include <algorithm>
20#include <cassert>
21#include <climits>
22#include <cstddef>
23#include <cstdint>
24#include <limits>
25#include <utility>
26
27namespace llvm {
28
29/// This is a 'bitvector' (really, a variable-sized bit array), optimized for
30/// the case when the array is small. It contains one pointer-sized field, which
31/// is directly used as a plain collection of bits when possible, or as a
32/// pointer to a larger heap-allocated array when necessary. This allows normal
33/// "small" cases to be fast without losing generality for large inputs.
34class SmallBitVector {
35 // TODO: In "large" mode, a pointer to a BitVector is used, leading to an
36 // unnecessary level of indirection. It would be more efficient to use a
37 // pointer to memory containing size, allocation size, and the array of bits.
38 uintptr_t X = 1;
39
40 enum {
41 // The number of bits in this class.
42 NumBaseBits = sizeof(uintptr_t) * CHAR_BIT8,
43
44 // One bit is used to discriminate between small and large mode. The
45 // remaining bits are used for the small-mode representation.
46 SmallNumRawBits = NumBaseBits - 1,
47
48 // A few more bits are used to store the size of the bit set in small mode.
49 // Theoretically this is a ceil-log2. These bits are encoded in the most
50 // significant bits of the raw bits.
51 SmallNumSizeBits = (NumBaseBits == 32 ? 5 :
52 NumBaseBits == 64 ? 6 :
53 SmallNumRawBits),
54
55 // The remaining bits are used to store the actual set in small mode.
56 SmallNumDataBits = SmallNumRawBits - SmallNumSizeBits
57 };
58
59 static_assert(NumBaseBits == 64 || NumBaseBits == 32,
60 "Unsupported word size");
61
62public:
63 using size_type = unsigned;
64
65 // Encapsulation of a single bit.
66 class reference {
67 SmallBitVector &TheVector;
68 unsigned BitPos;
69
70 public:
71 reference(SmallBitVector &b, unsigned Idx) : TheVector(b), BitPos(Idx) {}
72
73 reference(const reference&) = default;
74
75 reference& operator=(reference t) {
76 *this = bool(t);
77 return *this;
78 }
79
80 reference& operator=(bool t) {
81 if (t)
82 TheVector.set(BitPos);
83 else
84 TheVector.reset(BitPos);
85 return *this;
86 }
87
88 operator bool() const {
89 return const_cast<const SmallBitVector &>(TheVector).operator[](BitPos);
90 }
91 };
92
93private:
94 BitVector *getPointer() const {
95 assert(!isSmall())((!isSmall()) ? static_cast<void> (0) : __assert_fail (
"!isSmall()", "/build/llvm-toolchain-snapshot-9~svn362543/include/llvm/ADT/SmallBitVector.h"
, 95, __PRETTY_FUNCTION__))
;
96 return reinterpret_cast<BitVector *>(X);
97 }
98
99 void switchToSmall(uintptr_t NewSmallBits, size_t NewSize) {
100 X = 1;
101 setSmallSize(NewSize);
102 setSmallBits(NewSmallBits);
103 }
104
105 void switchToLarge(BitVector *BV) {
106 X = reinterpret_cast<uintptr_t>(BV);
107 assert(!isSmall() && "Tried to use an unaligned pointer")((!isSmall() && "Tried to use an unaligned pointer") ?
static_cast<void> (0) : __assert_fail ("!isSmall() && \"Tried to use an unaligned pointer\""
, "/build/llvm-toolchain-snapshot-9~svn362543/include/llvm/ADT/SmallBitVector.h"
, 107, __PRETTY_FUNCTION__))
;
108 }
109
110 // Return all the bits used for the "small" representation; this includes
111 // bits for the size as well as the element bits.
112 uintptr_t getSmallRawBits() const {
113 assert(isSmall())((isSmall()) ? static_cast<void> (0) : __assert_fail ("isSmall()"
, "/build/llvm-toolchain-snapshot-9~svn362543/include/llvm/ADT/SmallBitVector.h"
, 113, __PRETTY_FUNCTION__))
;
114 return X >> 1;
115 }
116
117 void setSmallRawBits(uintptr_t NewRawBits) {
118 assert(isSmall())((isSmall()) ? static_cast<void> (0) : __assert_fail ("isSmall()"
, "/build/llvm-toolchain-snapshot-9~svn362543/include/llvm/ADT/SmallBitVector.h"
, 118, __PRETTY_FUNCTION__))
;
119 X = (NewRawBits << 1) | uintptr_t(1);
120 }
121
122 // Return the size.
123 size_t getSmallSize() const { return getSmallRawBits() >> SmallNumDataBits; }
124
125 void setSmallSize(size_t Size) {
126 setSmallRawBits(getSmallBits() | (Size << SmallNumDataBits));
127 }
128
129 // Return the element bits.
130 uintptr_t getSmallBits() const {
131 return getSmallRawBits() & ~(~uintptr_t(0) << getSmallSize());
132 }
133
134 void setSmallBits(uintptr_t NewBits) {
135 setSmallRawBits((NewBits & ~(~uintptr_t(0) << getSmallSize())) |
136 (getSmallSize() << SmallNumDataBits));
137 }
138
139public:
140 /// Creates an empty bitvector.
141 SmallBitVector() = default;
142
143 /// Creates a bitvector of specified number of bits. All bits are initialized
144 /// to the specified value.
145 explicit SmallBitVector(unsigned s, bool t = false) {
146 if (s <= SmallNumDataBits)
16
Assuming 's' is > SmallNumDataBits
17
Taking false branch
147 switchToSmall(t ? ~uintptr_t(0) : 0, s);
148 else
149 switchToLarge(new BitVector(s, t));
18
Memory is allocated
150 }
151
152 /// SmallBitVector copy ctor.
153 SmallBitVector(const SmallBitVector &RHS) {
154 if (RHS.isSmall())
155 X = RHS.X;
156 else
157 switchToLarge(new BitVector(*RHS.getPointer()));
158 }
159
160 SmallBitVector(SmallBitVector &&RHS) : X(RHS.X) {
161 RHS.X = 1;
162 }
163
164 ~SmallBitVector() {
165 if (!isSmall())
166 delete getPointer();
167 }
168
169 using const_set_bits_iterator = const_set_bits_iterator_impl<SmallBitVector>;
170 using set_iterator = const_set_bits_iterator;
171
172 const_set_bits_iterator set_bits_begin() const {
173 return const_set_bits_iterator(*this);
174 }
175
176 const_set_bits_iterator set_bits_end() const {
177 return const_set_bits_iterator(*this, -1);
178 }
179
180 iterator_range<const_set_bits_iterator> set_bits() const {
181 return make_range(set_bits_begin(), set_bits_end());
182 }
183
184 bool isSmall() const { return X & uintptr_t(1); }
185
186 /// Tests whether there are no bits in this bitvector.
187 bool empty() const {
188 return isSmall() ? getSmallSize() == 0 : getPointer()->empty();
189 }
190
191 /// Returns the number of bits in this bitvector.
192 size_t size() const {
193 return isSmall() ? getSmallSize() : getPointer()->size();
194 }
195
196 /// Returns the number of bits which are set.
197 size_type count() const {
198 if (isSmall()) {
199 uintptr_t Bits = getSmallBits();
200 return countPopulation(Bits);
201 }
202 return getPointer()->count();
203 }
204
205 /// Returns true if any bit is set.
206 bool any() const {
207 if (isSmall())
208 return getSmallBits() != 0;
209 return getPointer()->any();
210 }
211
212 /// Returns true if all bits are set.
213 bool all() const {
214 if (isSmall())
215 return getSmallBits() == (uintptr_t(1) << getSmallSize()) - 1;
216 return getPointer()->all();
217 }
218
219 /// Returns true if none of the bits are set.
220 bool none() const {
221 if (isSmall())
222 return getSmallBits() == 0;
223 return getPointer()->none();
224 }
225
226 /// Returns the index of the first set bit, -1 if none of the bits are set.
227 int find_first() const {
228 if (isSmall()) {
229 uintptr_t Bits = getSmallBits();
230 if (Bits == 0)
231 return -1;
232 return countTrailingZeros(Bits);
233 }
234 return getPointer()->find_first();
235 }
236
237 int find_last() const {
238 if (isSmall()) {
239 uintptr_t Bits = getSmallBits();
240 if (Bits == 0)
241 return -1;
242 return NumBaseBits - countLeadingZeros(Bits) - 1;
243 }
244 return getPointer()->find_last();
245 }
246
247 /// Returns the index of the first unset bit, -1 if all of the bits are set.
248 int find_first_unset() const {
249 if (isSmall()) {
250 if (count() == getSmallSize())
251 return -1;
252
253 uintptr_t Bits = getSmallBits();
254 return countTrailingOnes(Bits);
255 }
256 return getPointer()->find_first_unset();
257 }
258
259 int find_last_unset() const {
260 if (isSmall()) {
261 if (count() == getSmallSize())
262 return -1;
263
264 uintptr_t Bits = getSmallBits();
265 // Set unused bits.
266 Bits |= ~uintptr_t(0) << getSmallSize();
267 return NumBaseBits - countLeadingOnes(Bits) - 1;
268 }
269 return getPointer()->find_last_unset();
270 }
271
272 /// Returns the index of the next set bit following the "Prev" bit.
273 /// Returns -1 if the next set bit is not found.
274 int find_next(unsigned Prev) const {
275 if (isSmall()) {
276 uintptr_t Bits = getSmallBits();
277 // Mask off previous bits.
278 Bits &= ~uintptr_t(0) << (Prev + 1);
279 if (Bits == 0 || Prev + 1 >= getSmallSize())
280 return -1;
281 return countTrailingZeros(Bits);
282 }
283 return getPointer()->find_next(Prev);
284 }
285
286 /// Returns the index of the next unset bit following the "Prev" bit.
287 /// Returns -1 if the next unset bit is not found.
288 int find_next_unset(unsigned Prev) const {
289 if (isSmall()) {
290 ++Prev;
291 uintptr_t Bits = getSmallBits();
292 // Mask in previous bits.
293 uintptr_t Mask = (1 << Prev) - 1;
294 Bits |= Mask;
295
296 if (Bits == ~uintptr_t(0) || Prev + 1 >= getSmallSize())
297 return -1;
298 return countTrailingOnes(Bits);
299 }
300 return getPointer()->find_next_unset(Prev);
301 }
302
303 /// find_prev - Returns the index of the first set bit that precedes the
304 /// the bit at \p PriorTo. Returns -1 if all previous bits are unset.
305 int find_prev(unsigned PriorTo) const {
306 if (isSmall()) {
307 if (PriorTo == 0)
308 return -1;
309
310 --PriorTo;
311 uintptr_t Bits = getSmallBits();
312 Bits &= maskTrailingOnes<uintptr_t>(PriorTo + 1);
313 if (Bits == 0)
314 return -1;
315
316 return NumBaseBits - countLeadingZeros(Bits) - 1;
317 }
318 return getPointer()->find_prev(PriorTo);
319 }
320
321 /// Clear all bits.
322 void clear() {
323 if (!isSmall())
324 delete getPointer();
325 switchToSmall(0, 0);
326 }
327
328 /// Grow or shrink the bitvector.
329 void resize(unsigned N, bool t = false) {
330 if (!isSmall()) {
331 getPointer()->resize(N, t);
332 } else if (SmallNumDataBits >= N) {
333 uintptr_t NewBits = t ? ~uintptr_t(0) << getSmallSize() : 0;
334 setSmallSize(N);
335 setSmallBits(NewBits | getSmallBits());
336 } else {
337 BitVector *BV = new BitVector(N, t);
338 uintptr_t OldBits = getSmallBits();
339 for (size_t i = 0, e = getSmallSize(); i != e; ++i)
340 (*BV)[i] = (OldBits >> i) & 1;
341 switchToLarge(BV);
342 }
343 }
344
345 void reserve(unsigned N) {
346 if (isSmall()) {
347 if (N > SmallNumDataBits) {
348 uintptr_t OldBits = getSmallRawBits();
349 size_t SmallSize = getSmallSize();
350 BitVector *BV = new BitVector(SmallSize);
351 for (size_t i = 0; i < SmallSize; ++i)
352 if ((OldBits >> i) & 1)
353 BV->set(i);
354 BV->reserve(N);
355 switchToLarge(BV);
356 }
357 } else {
358 getPointer()->reserve(N);
359 }
360 }
361
362 // Set, reset, flip
363 SmallBitVector &set() {
364 if (isSmall())
365 setSmallBits(~uintptr_t(0));
366 else
367 getPointer()->set();
368 return *this;
369 }
370
371 SmallBitVector &set(unsigned Idx) {
372 if (isSmall()) {
373 assert(Idx <= static_cast<unsigned>(((Idx <= static_cast<unsigned>( std::numeric_limits<
uintptr_t>::digits) && "undefined behavior") ? static_cast
<void> (0) : __assert_fail ("Idx <= static_cast<unsigned>( std::numeric_limits<uintptr_t>::digits) && \"undefined behavior\""
, "/build/llvm-toolchain-snapshot-9~svn362543/include/llvm/ADT/SmallBitVector.h"
, 375, __PRETTY_FUNCTION__))
374 std::numeric_limits<uintptr_t>::digits) &&((Idx <= static_cast<unsigned>( std::numeric_limits<
uintptr_t>::digits) && "undefined behavior") ? static_cast
<void> (0) : __assert_fail ("Idx <= static_cast<unsigned>( std::numeric_limits<uintptr_t>::digits) && \"undefined behavior\""
, "/build/llvm-toolchain-snapshot-9~svn362543/include/llvm/ADT/SmallBitVector.h"
, 375, __PRETTY_FUNCTION__))
375 "undefined behavior")((Idx <= static_cast<unsigned>( std::numeric_limits<
uintptr_t>::digits) && "undefined behavior") ? static_cast
<void> (0) : __assert_fail ("Idx <= static_cast<unsigned>( std::numeric_limits<uintptr_t>::digits) && \"undefined behavior\""
, "/build/llvm-toolchain-snapshot-9~svn362543/include/llvm/ADT/SmallBitVector.h"
, 375, __PRETTY_FUNCTION__))
;
376 setSmallBits(getSmallBits() | (uintptr_t(1) << Idx));
377 }
378 else
379 getPointer()->set(Idx);
380 return *this;
381 }
382
383 /// Efficiently set a range of bits in [I, E)
384 SmallBitVector &set(unsigned I, unsigned E) {
385 assert(I <= E && "Attempted to set backwards range!")((I <= E && "Attempted to set backwards range!") ?
static_cast<void> (0) : __assert_fail ("I <= E && \"Attempted to set backwards range!\""
, "/build/llvm-toolchain-snapshot-9~svn362543/include/llvm/ADT/SmallBitVector.h"
, 385, __PRETTY_FUNCTION__))
;
386 assert(E <= size() && "Attempted to set out-of-bounds range!")((E <= size() && "Attempted to set out-of-bounds range!"
) ? static_cast<void> (0) : __assert_fail ("E <= size() && \"Attempted to set out-of-bounds range!\""
, "/build/llvm-toolchain-snapshot-9~svn362543/include/llvm/ADT/SmallBitVector.h"
, 386, __PRETTY_FUNCTION__))
;
387 if (I == E) return *this;
388 if (isSmall()) {
389 uintptr_t EMask = ((uintptr_t)1) << E;
390 uintptr_t IMask = ((uintptr_t)1) << I;
391 uintptr_t Mask = EMask - IMask;
392 setSmallBits(getSmallBits() | Mask);
393 } else
394 getPointer()->set(I, E);
395 return *this;
396 }
397
398 SmallBitVector &reset() {
399 if (isSmall())
400 setSmallBits(0);
401 else
402 getPointer()->reset();
403 return *this;
404 }
405
406 SmallBitVector &reset(unsigned Idx) {
407 if (isSmall())
408 setSmallBits(getSmallBits() & ~(uintptr_t(1) << Idx));
409 else
410 getPointer()->reset(Idx);
411 return *this;
412 }
413
414 /// Efficiently reset a range of bits in [I, E)
415 SmallBitVector &reset(unsigned I, unsigned E) {
416 assert(I <= E && "Attempted to reset backwards range!")((I <= E && "Attempted to reset backwards range!")
? static_cast<void> (0) : __assert_fail ("I <= E && \"Attempted to reset backwards range!\""
, "/build/llvm-toolchain-snapshot-9~svn362543/include/llvm/ADT/SmallBitVector.h"
, 416, __PRETTY_FUNCTION__))
;
417 assert(E <= size() && "Attempted to reset out-of-bounds range!")((E <= size() && "Attempted to reset out-of-bounds range!"
) ? static_cast<void> (0) : __assert_fail ("E <= size() && \"Attempted to reset out-of-bounds range!\""
, "/build/llvm-toolchain-snapshot-9~svn362543/include/llvm/ADT/SmallBitVector.h"
, 417, __PRETTY_FUNCTION__))
;
418 if (I == E) return *this;
419 if (isSmall()) {
420 uintptr_t EMask = ((uintptr_t)1) << E;
421 uintptr_t IMask = ((uintptr_t)1) << I;
422 uintptr_t Mask = EMask - IMask;
423 setSmallBits(getSmallBits() & ~Mask);
424 } else
425 getPointer()->reset(I, E);
426 return *this;
427 }
428
429 SmallBitVector &flip() {
430 if (isSmall())
431 setSmallBits(~getSmallBits());
432 else
433 getPointer()->flip();
434 return *this;
435 }
436
437 SmallBitVector &flip(unsigned Idx) {
438 if (isSmall())
439 setSmallBits(getSmallBits() ^ (uintptr_t(1) << Idx));
440 else
441 getPointer()->flip(Idx);
442 return *this;
443 }
444
445 // No argument flip.
446 SmallBitVector operator~() const {
447 return SmallBitVector(*this).flip();
448 }
449
450 // Indexing.
451 reference operator[](unsigned Idx) {
452 assert(Idx < size() && "Out-of-bounds Bit access.")((Idx < size() && "Out-of-bounds Bit access.") ? static_cast
<void> (0) : __assert_fail ("Idx < size() && \"Out-of-bounds Bit access.\""
, "/build/llvm-toolchain-snapshot-9~svn362543/include/llvm/ADT/SmallBitVector.h"
, 452, __PRETTY_FUNCTION__))
;
453 return reference(*this, Idx);
454 }
455
456 bool operator[](unsigned Idx) const {
457 assert(Idx < size() && "Out-of-bounds Bit access.")((Idx < size() && "Out-of-bounds Bit access.") ? static_cast
<void> (0) : __assert_fail ("Idx < size() && \"Out-of-bounds Bit access.\""
, "/build/llvm-toolchain-snapshot-9~svn362543/include/llvm/ADT/SmallBitVector.h"
, 457, __PRETTY_FUNCTION__))
;
458 if (isSmall())
459 return ((getSmallBits() >> Idx) & 1) != 0;
460 return getPointer()->operator[](Idx);
461 }
462
463 bool test(unsigned Idx) const {
464 return (*this)[Idx];
465 }
466
467 // Push single bit to end of vector.
468 void push_back(bool Val) {
469 resize(size() + 1, Val);
470 }
471
472 /// Test if any common bits are set.
473 bool anyCommon(const SmallBitVector &RHS) const {
474 if (isSmall() && RHS.isSmall())
475 return (getSmallBits() & RHS.getSmallBits()) != 0;
476 if (!isSmall() && !RHS.isSmall())
477 return getPointer()->anyCommon(*RHS.getPointer());
478
479 for (unsigned i = 0, e = std::min(size(), RHS.size()); i != e; ++i)
480 if (test(i) && RHS.test(i))
481 return true;
482 return false;
483 }
484
485 // Comparison operators.
486 bool operator==(const SmallBitVector &RHS) const {
487 if (size() != RHS.size())
488 return false;
489 if (isSmall() && RHS.isSmall())
490 return getSmallBits() == RHS.getSmallBits();
491 else if (!isSmall() && !RHS.isSmall())
492 return *getPointer() == *RHS.getPointer();
493 else {
494 for (size_t i = 0, e = size(); i != e; ++i) {
495 if ((*this)[i] != RHS[i])
496 return false;
497 }
498 return true;
499 }
500 }
501
502 bool operator!=(const SmallBitVector &RHS) const {
503 return !(*this == RHS);
504 }
505
506 // Intersection, union, disjoint union.
507 // FIXME BitVector::operator&= does not resize the LHS but this does
508 SmallBitVector &operator&=(const SmallBitVector &RHS) {
509 resize(std::max(size(), RHS.size()));
510 if (isSmall() && RHS.isSmall())
511 setSmallBits(getSmallBits() & RHS.getSmallBits());
512 else if (!isSmall() && !RHS.isSmall())
513 getPointer()->operator&=(*RHS.getPointer());
514 else {
515 size_t i, e;
516 for (i = 0, e = std::min(size(), RHS.size()); i != e; ++i)
517 (*this)[i] = test(i) && RHS.test(i);
518 for (e = size(); i != e; ++i)
519 reset(i);
520 }
521 return *this;
522 }
523
524 /// Reset bits that are set in RHS. Same as *this &= ~RHS.
525 SmallBitVector &reset(const SmallBitVector &RHS) {
526 if (isSmall() && RHS.isSmall())
527 setSmallBits(getSmallBits() & ~RHS.getSmallBits());
528 else if (!isSmall() && !RHS.isSmall())
529 getPointer()->reset(*RHS.getPointer());
530 else
531 for (unsigned i = 0, e = std::min(size(), RHS.size()); i != e; ++i)
532 if (RHS.test(i))
533 reset(i);
534
535 return *this;
536 }
537
538 /// Check if (This - RHS) is zero. This is the same as reset(RHS) and any().
539 bool test(const SmallBitVector &RHS) const {
540 if (isSmall() && RHS.isSmall())
541 return (getSmallBits() & ~RHS.getSmallBits()) != 0;
542 if (!isSmall() && !RHS.isSmall())
543 return getPointer()->test(*RHS.getPointer());
544
545 unsigned i, e;
546 for (i = 0, e = std::min(size(), RHS.size()); i != e; ++i)
547 if (test(i) && !RHS.test(i))
548 return true;
549
550 for (e = size(); i != e; ++i)
551 if (test(i))
552 return true;
553
554 return false;
555 }
556
557 SmallBitVector &operator|=(const SmallBitVector &RHS) {
558 resize(std::max(size(), RHS.size()));
559 if (isSmall() && RHS.isSmall())
560 setSmallBits(getSmallBits() | RHS.getSmallBits());
561 else if (!isSmall() && !RHS.isSmall())
562 getPointer()->operator|=(*RHS.getPointer());
563 else {
564 for (size_t i = 0, e = RHS.size(); i != e; ++i)
565 (*this)[i] = test(i) || RHS.test(i);
566 }
567 return *this;
568 }
569
570 SmallBitVector &operator^=(const SmallBitVector &RHS) {
571 resize(std::max(size(), RHS.size()));
572 if (isSmall() && RHS.isSmall())
573 setSmallBits(getSmallBits() ^ RHS.getSmallBits());
574 else if (!isSmall() && !RHS.isSmall())
575 getPointer()->operator^=(*RHS.getPointer());
576 else {
577 for (size_t i = 0, e = RHS.size(); i != e; ++i)
578 (*this)[i] = test(i) != RHS.test(i);
579 }
580 return *this;
581 }
582
583 SmallBitVector &operator<<=(unsigned N) {
584 if (isSmall())
585 setSmallBits(getSmallBits() << N);
586 else
587 getPointer()->operator<<=(N);
588 return *this;
589 }
590
591 SmallBitVector &operator>>=(unsigned N) {
592 if (isSmall())
593 setSmallBits(getSmallBits() >> N);
594 else
595 getPointer()->operator>>=(N);
596 return *this;
597 }
598
599 // Assignment operator.
600 const SmallBitVector &operator=(const SmallBitVector &RHS) {
601 if (isSmall()) {
602 if (RHS.isSmall())
603 X = RHS.X;
604 else
605 switchToLarge(new BitVector(*RHS.getPointer()));
606 } else {
607 if (!RHS.isSmall())
608 *getPointer() = *RHS.getPointer();
609 else {
610 delete getPointer();
611 X = RHS.X;
612 }
613 }
614 return *this;
615 }
616
617 const SmallBitVector &operator=(SmallBitVector &&RHS) {
618 if (this != &RHS) {
619 clear();
620 swap(RHS);
621 }
622 return *this;
623 }
624
625 void swap(SmallBitVector &RHS) {
626 std::swap(X, RHS.X);
627 }
628
629 /// Add '1' bits from Mask to this vector. Don't resize.
630 /// This computes "*this |= Mask".
631 void setBitsInMask(const uint32_t *Mask, unsigned MaskWords = ~0u) {
632 if (isSmall())
633 applyMask<true, false>(Mask, MaskWords);
634 else
635 getPointer()->setBitsInMask(Mask, MaskWords);
636 }
637
638 /// Clear any bits in this vector that are set in Mask. Don't resize.
639 /// This computes "*this &= ~Mask".
640 void clearBitsInMask(const uint32_t *Mask, unsigned MaskWords = ~0u) {
641 if (isSmall())
642 applyMask<false, false>(Mask, MaskWords);
643 else
644 getPointer()->clearBitsInMask(Mask, MaskWords);
645 }
646
647 /// Add a bit to this vector for every '0' bit in Mask. Don't resize.
648 /// This computes "*this |= ~Mask".
649 void setBitsNotInMask(const uint32_t *Mask, unsigned MaskWords = ~0u) {
650 if (isSmall())
651 applyMask<true, true>(Mask, MaskWords);
652 else
653 getPointer()->setBitsNotInMask(Mask, MaskWords);
654 }
655
656 /// Clear a bit in this vector for every '0' bit in Mask. Don't resize.
657 /// This computes "*this &= Mask".
658 void clearBitsNotInMask(const uint32_t *Mask, unsigned MaskWords = ~0u) {
659 if (isSmall())
660 applyMask<false, true>(Mask, MaskWords);
661 else
662 getPointer()->clearBitsNotInMask(Mask, MaskWords);
663 }
664
665private:
666 template <bool AddBits, bool InvertMask>
667 void applyMask(const uint32_t *Mask, unsigned MaskWords) {
668 assert(MaskWords <= sizeof(uintptr_t) && "Mask is larger than base!")((MaskWords <= sizeof(uintptr_t) && "Mask is larger than base!"
) ? static_cast<void> (0) : __assert_fail ("MaskWords <= sizeof(uintptr_t) && \"Mask is larger than base!\""
, "/build/llvm-toolchain-snapshot-9~svn362543/include/llvm/ADT/SmallBitVector.h"
, 668, __PRETTY_FUNCTION__))
;
669 uintptr_t M = Mask[0];
670 if (NumBaseBits == 64)
671 M |= uint64_t(Mask[1]) << 32;
672 if (InvertMask)
673 M = ~M;
674 if (AddBits)
675 setSmallBits(getSmallBits() | M);
676 else
677 setSmallBits(getSmallBits() & ~M);
678 }
679};
680
681inline SmallBitVector
682operator&(const SmallBitVector &LHS, const SmallBitVector &RHS) {
683 SmallBitVector Result(LHS);
684 Result &= RHS;
685 return Result;
686}
687
688inline SmallBitVector
689operator|(const SmallBitVector &LHS, const SmallBitVector &RHS) {
690 SmallBitVector Result(LHS);
691 Result |= RHS;
692 return Result;
693}
694
695inline SmallBitVector
696operator^(const SmallBitVector &LHS, const SmallBitVector &RHS) {
697 SmallBitVector Result(LHS);
698 Result ^= RHS;
699 return Result;
700}
701
702} // end namespace llvm
703
704namespace std {
705
706/// Implement std::swap in terms of BitVector swap.
707inline void
708swap(llvm::SmallBitVector &LHS, llvm::SmallBitVector &RHS) {
709 LHS.swap(RHS);
710}
711
712} // end namespace std
713
714#endif // LLVM_ADT_SMALLBITVECTOR_H