File: | clang/lib/Sema/SemaTemplateDeduction.cpp |
Warning: | line 2193, column 42 Called C++ object pointer is null |
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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/RecursiveASTVisitor.h" | |||
28 | #include "clang/AST/TemplateBase.h" | |||
29 | #include "clang/AST/TemplateName.h" | |||
30 | #include "clang/AST/Type.h" | |||
31 | #include "clang/AST/TypeLoc.h" | |||
32 | #include "clang/AST/UnresolvedSet.h" | |||
33 | #include "clang/Basic/AddressSpaces.h" | |||
34 | #include "clang/Basic/ExceptionSpecificationType.h" | |||
35 | #include "clang/Basic/LLVM.h" | |||
36 | #include "clang/Basic/LangOptions.h" | |||
37 | #include "clang/Basic/PartialDiagnostic.h" | |||
38 | #include "clang/Basic/SourceLocation.h" | |||
39 | #include "clang/Basic/Specifiers.h" | |||
40 | #include "clang/Sema/Ownership.h" | |||
41 | #include "clang/Sema/Sema.h" | |||
42 | #include "clang/Sema/Template.h" | |||
43 | #include "llvm/ADT/APInt.h" | |||
44 | #include "llvm/ADT/APSInt.h" | |||
45 | #include "llvm/ADT/ArrayRef.h" | |||
46 | #include "llvm/ADT/DenseMap.h" | |||
47 | #include "llvm/ADT/FoldingSet.h" | |||
48 | #include "llvm/ADT/Optional.h" | |||
49 | #include "llvm/ADT/SmallBitVector.h" | |||
50 | #include "llvm/ADT/SmallPtrSet.h" | |||
51 | #include "llvm/ADT/SmallVector.h" | |||
52 | #include "llvm/Support/Casting.h" | |||
53 | #include "llvm/Support/Compiler.h" | |||
54 | #include "llvm/Support/ErrorHandling.h" | |||
55 | #include <algorithm> | |||
56 | #include <cassert> | |||
57 | #include <tuple> | |||
58 | #include <utility> | |||
59 | ||||
60 | namespace clang { | |||
61 | ||||
62 | /// Various flags that control template argument deduction. | |||
63 | /// | |||
64 | /// These flags can be bitwise-OR'd together. | |||
65 | enum TemplateDeductionFlags { | |||
66 | /// No template argument deduction flags, which indicates the | |||
67 | /// strictest results for template argument deduction (as used for, e.g., | |||
68 | /// matching class template partial specializations). | |||
69 | TDF_None = 0, | |||
70 | ||||
71 | /// Within template argument deduction from a function call, we are | |||
72 | /// matching with a parameter type for which the original parameter was | |||
73 | /// a reference. | |||
74 | TDF_ParamWithReferenceType = 0x1, | |||
75 | ||||
76 | /// Within template argument deduction from a function call, we | |||
77 | /// are matching in a case where we ignore cv-qualifiers. | |||
78 | TDF_IgnoreQualifiers = 0x02, | |||
79 | ||||
80 | /// Within template argument deduction from a function call, | |||
81 | /// we are matching in a case where we can perform template argument | |||
82 | /// deduction from a template-id of a derived class of the argument type. | |||
83 | TDF_DerivedClass = 0x04, | |||
84 | ||||
85 | /// Allow non-dependent types to differ, e.g., when performing | |||
86 | /// template argument deduction from a function call where conversions | |||
87 | /// may apply. | |||
88 | TDF_SkipNonDependent = 0x08, | |||
89 | ||||
90 | /// Whether we are performing template argument deduction for | |||
91 | /// parameters and arguments in a top-level template argument | |||
92 | TDF_TopLevelParameterTypeList = 0x10, | |||
93 | ||||
94 | /// Within template argument deduction from overload resolution per | |||
95 | /// C++ [over.over] allow matching function types that are compatible in | |||
96 | /// terms of noreturn and default calling convention adjustments, or | |||
97 | /// similarly matching a declared template specialization against a | |||
98 | /// possible template, per C++ [temp.deduct.decl]. In either case, permit | |||
99 | /// deduction where the parameter is a function type that can be converted | |||
100 | /// to the argument type. | |||
101 | TDF_AllowCompatibleFunctionType = 0x20, | |||
102 | ||||
103 | /// Within template argument deduction for a conversion function, we are | |||
104 | /// matching with an argument type for which the original argument was | |||
105 | /// a reference. | |||
106 | TDF_ArgWithReferenceType = 0x40, | |||
107 | }; | |||
108 | } | |||
109 | ||||
110 | using namespace clang; | |||
111 | using namespace sema; | |||
112 | ||||
113 | /// Compare two APSInts, extending and switching the sign as | |||
114 | /// necessary to compare their values regardless of underlying type. | |||
115 | static bool hasSameExtendedValue(llvm::APSInt X, llvm::APSInt Y) { | |||
116 | if (Y.getBitWidth() > X.getBitWidth()) | |||
117 | X = X.extend(Y.getBitWidth()); | |||
118 | else if (Y.getBitWidth() < X.getBitWidth()) | |||
119 | Y = Y.extend(X.getBitWidth()); | |||
120 | ||||
121 | // If there is a signedness mismatch, correct it. | |||
122 | if (X.isSigned() != Y.isSigned()) { | |||
123 | // If the signed value is negative, then the values cannot be the same. | |||
124 | if ((Y.isSigned() && Y.isNegative()) || (X.isSigned() && X.isNegative())) | |||
125 | return false; | |||
126 | ||||
127 | Y.setIsSigned(true); | |||
128 | X.setIsSigned(true); | |||
129 | } | |||
130 | ||||
131 | return X == Y; | |||
132 | } | |||
133 | ||||
134 | static Sema::TemplateDeductionResult | |||
135 | DeduceTemplateArguments(Sema &S, | |||
136 | TemplateParameterList *TemplateParams, | |||
137 | const TemplateArgument &Param, | |||
138 | TemplateArgument Arg, | |||
139 | TemplateDeductionInfo &Info, | |||
140 | SmallVectorImpl<DeducedTemplateArgument> &Deduced); | |||
141 | ||||
142 | static Sema::TemplateDeductionResult | |||
143 | DeduceTemplateArgumentsByTypeMatch(Sema &S, | |||
144 | TemplateParameterList *TemplateParams, | |||
145 | QualType Param, | |||
146 | QualType Arg, | |||
147 | TemplateDeductionInfo &Info, | |||
148 | SmallVectorImpl<DeducedTemplateArgument> & | |||
149 | Deduced, | |||
150 | unsigned TDF, | |||
151 | bool PartialOrdering = false, | |||
152 | bool DeducedFromArrayBound = false); | |||
153 | ||||
154 | static Sema::TemplateDeductionResult | |||
155 | DeduceTemplateArguments(Sema &S, TemplateParameterList *TemplateParams, | |||
156 | ArrayRef<TemplateArgument> Params, | |||
157 | ArrayRef<TemplateArgument> Args, | |||
158 | TemplateDeductionInfo &Info, | |||
159 | SmallVectorImpl<DeducedTemplateArgument> &Deduced, | |||
160 | bool NumberOfArgumentsMustMatch); | |||
161 | ||||
162 | static void MarkUsedTemplateParameters(ASTContext &Ctx, | |||
163 | const TemplateArgument &TemplateArg, | |||
164 | bool OnlyDeduced, unsigned Depth, | |||
165 | llvm::SmallBitVector &Used); | |||
166 | ||||
167 | static void MarkUsedTemplateParameters(ASTContext &Ctx, QualType T, | |||
168 | bool OnlyDeduced, unsigned Level, | |||
169 | llvm::SmallBitVector &Deduced); | |||
170 | ||||
171 | /// If the given expression is of a form that permits the deduction | |||
172 | /// of a non-type template parameter, return the declaration of that | |||
173 | /// non-type template parameter. | |||
174 | static const NonTypeTemplateParmDecl * | |||
175 | getDeducedParameterFromExpr(const Expr *E, unsigned Depth) { | |||
176 | // If we are within an alias template, the expression may have undergone | |||
177 | // any number of parameter substitutions already. | |||
178 | while (true) { | |||
179 | if (const auto *IC = dyn_cast<ImplicitCastExpr>(E)) | |||
180 | E = IC->getSubExpr(); | |||
181 | else if (const auto *CE = dyn_cast<ConstantExpr>(E)) | |||
182 | E = CE->getSubExpr(); | |||
183 | else if (const auto *Subst = dyn_cast<SubstNonTypeTemplateParmExpr>(E)) | |||
184 | E = Subst->getReplacement(); | |||
185 | else if (const auto *CCE = dyn_cast<CXXConstructExpr>(E)) { | |||
186 | // Look through implicit copy construction from an lvalue of the same type. | |||
187 | if (CCE->getParenOrBraceRange().isValid()) | |||
188 | break; | |||
189 | // Note, there could be default arguments. | |||
190 | assert(CCE->getNumArgs() >= 1 && "implicit construct expr should have 1 arg")((CCE->getNumArgs() >= 1 && "implicit construct expr should have 1 arg" ) ? static_cast<void> (0) : __assert_fail ("CCE->getNumArgs() >= 1 && \"implicit construct expr should have 1 arg\"" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 190, __PRETTY_FUNCTION__)); | |||
191 | E = CCE->getArg(0); | |||
192 | } else | |||
193 | break; | |||
194 | } | |||
195 | ||||
196 | if (const auto *DRE = dyn_cast<DeclRefExpr>(E)) | |||
197 | if (const auto *NTTP = dyn_cast<NonTypeTemplateParmDecl>(DRE->getDecl())) | |||
198 | if (NTTP->getDepth() == Depth) | |||
199 | return NTTP; | |||
200 | ||||
201 | return nullptr; | |||
202 | } | |||
203 | ||||
204 | static const NonTypeTemplateParmDecl * | |||
205 | getDeducedParameterFromExpr(TemplateDeductionInfo &Info, Expr *E) { | |||
206 | return getDeducedParameterFromExpr(E, Info.getDeducedDepth()); | |||
207 | } | |||
208 | ||||
209 | /// Determine whether two declaration pointers refer to the same | |||
210 | /// declaration. | |||
211 | static bool isSameDeclaration(Decl *X, Decl *Y) { | |||
212 | if (NamedDecl *NX = dyn_cast<NamedDecl>(X)) | |||
213 | X = NX->getUnderlyingDecl(); | |||
214 | if (NamedDecl *NY = dyn_cast<NamedDecl>(Y)) | |||
215 | Y = NY->getUnderlyingDecl(); | |||
216 | ||||
217 | return X->getCanonicalDecl() == Y->getCanonicalDecl(); | |||
218 | } | |||
219 | ||||
220 | /// Verify that the given, deduced template arguments are compatible. | |||
221 | /// | |||
222 | /// \returns The deduced template argument, or a NULL template argument if | |||
223 | /// the deduced template arguments were incompatible. | |||
224 | static DeducedTemplateArgument | |||
225 | checkDeducedTemplateArguments(ASTContext &Context, | |||
226 | const DeducedTemplateArgument &X, | |||
227 | const DeducedTemplateArgument &Y) { | |||
228 | // We have no deduction for one or both of the arguments; they're compatible. | |||
229 | if (X.isNull()) | |||
230 | return Y; | |||
231 | if (Y.isNull()) | |||
232 | return X; | |||
233 | ||||
234 | // If we have two non-type template argument values deduced for the same | |||
235 | // parameter, they must both match the type of the parameter, and thus must | |||
236 | // match each other's type. As we're only keeping one of them, we must check | |||
237 | // for that now. The exception is that if either was deduced from an array | |||
238 | // bound, the type is permitted to differ. | |||
239 | if (!X.wasDeducedFromArrayBound() && !Y.wasDeducedFromArrayBound()) { | |||
240 | QualType XType = X.getNonTypeTemplateArgumentType(); | |||
241 | if (!XType.isNull()) { | |||
242 | QualType YType = Y.getNonTypeTemplateArgumentType(); | |||
243 | if (YType.isNull() || !Context.hasSameType(XType, YType)) | |||
244 | return DeducedTemplateArgument(); | |||
245 | } | |||
246 | } | |||
247 | ||||
248 | switch (X.getKind()) { | |||
249 | case TemplateArgument::Null: | |||
250 | llvm_unreachable("Non-deduced template arguments handled above")::llvm::llvm_unreachable_internal("Non-deduced template arguments handled above" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 250); | |||
251 | ||||
252 | case TemplateArgument::Type: | |||
253 | // If two template type arguments have the same type, they're compatible. | |||
254 | if (Y.getKind() == TemplateArgument::Type && | |||
255 | Context.hasSameType(X.getAsType(), Y.getAsType())) | |||
256 | return X; | |||
257 | ||||
258 | // If one of the two arguments was deduced from an array bound, the other | |||
259 | // supersedes it. | |||
260 | if (X.wasDeducedFromArrayBound() != Y.wasDeducedFromArrayBound()) | |||
261 | return X.wasDeducedFromArrayBound() ? Y : X; | |||
262 | ||||
263 | // The arguments are not compatible. | |||
264 | return DeducedTemplateArgument(); | |||
265 | ||||
266 | case TemplateArgument::Integral: | |||
267 | // If we deduced a constant in one case and either a dependent expression or | |||
268 | // declaration in another case, keep the integral constant. | |||
269 | // If both are integral constants with the same value, keep that value. | |||
270 | if (Y.getKind() == TemplateArgument::Expression || | |||
271 | Y.getKind() == TemplateArgument::Declaration || | |||
272 | (Y.getKind() == TemplateArgument::Integral && | |||
273 | hasSameExtendedValue(X.getAsIntegral(), Y.getAsIntegral()))) | |||
274 | return X.wasDeducedFromArrayBound() ? Y : X; | |||
275 | ||||
276 | // All other combinations are incompatible. | |||
277 | return DeducedTemplateArgument(); | |||
278 | ||||
279 | case TemplateArgument::Template: | |||
280 | if (Y.getKind() == TemplateArgument::Template && | |||
281 | Context.hasSameTemplateName(X.getAsTemplate(), Y.getAsTemplate())) | |||
282 | return X; | |||
283 | ||||
284 | // All other combinations are incompatible. | |||
285 | return DeducedTemplateArgument(); | |||
286 | ||||
287 | case TemplateArgument::TemplateExpansion: | |||
288 | if (Y.getKind() == TemplateArgument::TemplateExpansion && | |||
289 | Context.hasSameTemplateName(X.getAsTemplateOrTemplatePattern(), | |||
290 | Y.getAsTemplateOrTemplatePattern())) | |||
291 | return X; | |||
292 | ||||
293 | // All other combinations are incompatible. | |||
294 | return DeducedTemplateArgument(); | |||
295 | ||||
296 | case TemplateArgument::Expression: { | |||
297 | if (Y.getKind() != TemplateArgument::Expression) | |||
298 | return checkDeducedTemplateArguments(Context, Y, X); | |||
299 | ||||
300 | // Compare the expressions for equality | |||
301 | llvm::FoldingSetNodeID ID1, ID2; | |||
302 | X.getAsExpr()->Profile(ID1, Context, true); | |||
303 | Y.getAsExpr()->Profile(ID2, Context, true); | |||
304 | if (ID1 == ID2) | |||
305 | return X.wasDeducedFromArrayBound() ? Y : X; | |||
306 | ||||
307 | // Differing dependent expressions are incompatible. | |||
308 | return DeducedTemplateArgument(); | |||
309 | } | |||
310 | ||||
311 | case TemplateArgument::Declaration: | |||
312 | assert(!X.wasDeducedFromArrayBound())((!X.wasDeducedFromArrayBound()) ? static_cast<void> (0 ) : __assert_fail ("!X.wasDeducedFromArrayBound()", "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 312, __PRETTY_FUNCTION__)); | |||
313 | ||||
314 | // If we deduced a declaration and a dependent expression, keep the | |||
315 | // declaration. | |||
316 | if (Y.getKind() == TemplateArgument::Expression) | |||
317 | return X; | |||
318 | ||||
319 | // If we deduced a declaration and an integral constant, keep the | |||
320 | // integral constant and whichever type did not come from an array | |||
321 | // bound. | |||
322 | if (Y.getKind() == TemplateArgument::Integral) { | |||
323 | if (Y.wasDeducedFromArrayBound()) | |||
324 | return TemplateArgument(Context, Y.getAsIntegral(), | |||
325 | X.getParamTypeForDecl()); | |||
326 | return Y; | |||
327 | } | |||
328 | ||||
329 | // If we deduced two declarations, make sure that they refer to the | |||
330 | // same declaration. | |||
331 | if (Y.getKind() == TemplateArgument::Declaration && | |||
332 | isSameDeclaration(X.getAsDecl(), Y.getAsDecl())) | |||
333 | return X; | |||
334 | ||||
335 | // All other combinations are incompatible. | |||
336 | return DeducedTemplateArgument(); | |||
337 | ||||
338 | case TemplateArgument::NullPtr: | |||
339 | // If we deduced a null pointer and a dependent expression, keep the | |||
340 | // null pointer. | |||
341 | if (Y.getKind() == TemplateArgument::Expression) | |||
342 | return X; | |||
343 | ||||
344 | // If we deduced a null pointer and an integral constant, keep the | |||
345 | // integral constant. | |||
346 | if (Y.getKind() == TemplateArgument::Integral) | |||
347 | return Y; | |||
348 | ||||
349 | // If we deduced two null pointers, they are the same. | |||
350 | if (Y.getKind() == TemplateArgument::NullPtr) | |||
351 | return X; | |||
352 | ||||
353 | // All other combinations are incompatible. | |||
354 | return DeducedTemplateArgument(); | |||
355 | ||||
356 | case TemplateArgument::Pack: { | |||
357 | if (Y.getKind() != TemplateArgument::Pack || | |||
358 | X.pack_size() != Y.pack_size()) | |||
359 | return DeducedTemplateArgument(); | |||
360 | ||||
361 | llvm::SmallVector<TemplateArgument, 8> NewPack; | |||
362 | for (TemplateArgument::pack_iterator XA = X.pack_begin(), | |||
363 | XAEnd = X.pack_end(), | |||
364 | YA = Y.pack_begin(); | |||
365 | XA != XAEnd; ++XA, ++YA) { | |||
366 | TemplateArgument Merged = checkDeducedTemplateArguments( | |||
367 | Context, DeducedTemplateArgument(*XA, X.wasDeducedFromArrayBound()), | |||
368 | DeducedTemplateArgument(*YA, Y.wasDeducedFromArrayBound())); | |||
369 | if (Merged.isNull() && !(XA->isNull() && YA->isNull())) | |||
370 | return DeducedTemplateArgument(); | |||
371 | NewPack.push_back(Merged); | |||
372 | } | |||
373 | ||||
374 | return DeducedTemplateArgument( | |||
375 | TemplateArgument::CreatePackCopy(Context, NewPack), | |||
376 | X.wasDeducedFromArrayBound() && Y.wasDeducedFromArrayBound()); | |||
377 | } | |||
378 | } | |||
379 | ||||
380 | llvm_unreachable("Invalid TemplateArgument Kind!")::llvm::llvm_unreachable_internal("Invalid TemplateArgument Kind!" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 380); | |||
381 | } | |||
382 | ||||
383 | /// Deduce the value of the given non-type template parameter | |||
384 | /// as the given deduced template argument. All non-type template parameter | |||
385 | /// deduction is funneled through here. | |||
386 | static Sema::TemplateDeductionResult DeduceNonTypeTemplateArgument( | |||
387 | Sema &S, TemplateParameterList *TemplateParams, | |||
388 | const NonTypeTemplateParmDecl *NTTP, const DeducedTemplateArgument &NewDeduced, | |||
389 | QualType ValueType, TemplateDeductionInfo &Info, | |||
390 | SmallVectorImpl<DeducedTemplateArgument> &Deduced) { | |||
391 | 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-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 392, __PRETTY_FUNCTION__)) | |||
392 | "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-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 392, __PRETTY_FUNCTION__)); | |||
393 | ||||
394 | DeducedTemplateArgument Result = checkDeducedTemplateArguments( | |||
395 | S.Context, Deduced[NTTP->getIndex()], NewDeduced); | |||
396 | if (Result.isNull()) { | |||
397 | Info.Param = const_cast<NonTypeTemplateParmDecl*>(NTTP); | |||
398 | Info.FirstArg = Deduced[NTTP->getIndex()]; | |||
399 | Info.SecondArg = NewDeduced; | |||
400 | return Sema::TDK_Inconsistent; | |||
401 | } | |||
402 | ||||
403 | Deduced[NTTP->getIndex()] = Result; | |||
404 | if (!S.getLangOpts().CPlusPlus17) | |||
405 | return Sema::TDK_Success; | |||
406 | ||||
407 | if (NTTP->isExpandedParameterPack()) | |||
408 | // FIXME: We may still need to deduce parts of the type here! But we | |||
409 | // don't have any way to find which slice of the type to use, and the | |||
410 | // type stored on the NTTP itself is nonsense. Perhaps the type of an | |||
411 | // expanded NTTP should be a pack expansion type? | |||
412 | return Sema::TDK_Success; | |||
413 | ||||
414 | // Get the type of the parameter for deduction. If it's a (dependent) array | |||
415 | // or function type, we will not have decayed it yet, so do that now. | |||
416 | QualType ParamType = S.Context.getAdjustedParameterType(NTTP->getType()); | |||
417 | if (auto *Expansion = dyn_cast<PackExpansionType>(ParamType)) | |||
418 | ParamType = Expansion->getPattern(); | |||
419 | ||||
420 | // FIXME: It's not clear how deduction of a parameter of reference | |||
421 | // type from an argument (of non-reference type) should be performed. | |||
422 | // For now, we just remove reference types from both sides and let | |||
423 | // the final check for matching types sort out the mess. | |||
424 | ValueType = ValueType.getNonReferenceType(); | |||
425 | if (ParamType->isReferenceType()) | |||
426 | ParamType = ParamType.getNonReferenceType(); | |||
427 | else | |||
428 | // Top-level cv-qualifiers are irrelevant for a non-reference type. | |||
429 | ValueType = ValueType.getUnqualifiedType(); | |||
430 | ||||
431 | return DeduceTemplateArgumentsByTypeMatch( | |||
432 | S, TemplateParams, ParamType, ValueType, Info, Deduced, | |||
433 | TDF_SkipNonDependent, /*PartialOrdering=*/false, | |||
434 | /*ArrayBound=*/NewDeduced.wasDeducedFromArrayBound()); | |||
435 | } | |||
436 | ||||
437 | /// Deduce the value of the given non-type template parameter | |||
438 | /// from the given integral constant. | |||
439 | static Sema::TemplateDeductionResult DeduceNonTypeTemplateArgument( | |||
440 | Sema &S, TemplateParameterList *TemplateParams, | |||
441 | const NonTypeTemplateParmDecl *NTTP, const llvm::APSInt &Value, | |||
442 | QualType ValueType, bool DeducedFromArrayBound, TemplateDeductionInfo &Info, | |||
443 | SmallVectorImpl<DeducedTemplateArgument> &Deduced) { | |||
444 | return DeduceNonTypeTemplateArgument( | |||
445 | S, TemplateParams, NTTP, | |||
446 | DeducedTemplateArgument(S.Context, Value, ValueType, | |||
447 | DeducedFromArrayBound), | |||
448 | ValueType, Info, Deduced); | |||
449 | } | |||
450 | ||||
451 | /// Deduce the value of the given non-type template parameter | |||
452 | /// from the given null pointer template argument type. | |||
453 | static Sema::TemplateDeductionResult DeduceNullPtrTemplateArgument( | |||
454 | Sema &S, TemplateParameterList *TemplateParams, | |||
455 | const NonTypeTemplateParmDecl *NTTP, QualType NullPtrType, | |||
456 | TemplateDeductionInfo &Info, | |||
457 | SmallVectorImpl<DeducedTemplateArgument> &Deduced) { | |||
458 | Expr *Value = | |||
459 | S.ImpCastExprToType(new (S.Context) CXXNullPtrLiteralExpr( | |||
460 | S.Context.NullPtrTy, NTTP->getLocation()), | |||
461 | NullPtrType, CK_NullToPointer) | |||
462 | .get(); | |||
463 | return DeduceNonTypeTemplateArgument(S, TemplateParams, NTTP, | |||
464 | DeducedTemplateArgument(Value), | |||
465 | Value->getType(), Info, Deduced); | |||
466 | } | |||
467 | ||||
468 | /// Deduce the value of the given non-type template parameter | |||
469 | /// from the given type- or value-dependent expression. | |||
470 | /// | |||
471 | /// \returns true if deduction succeeded, false otherwise. | |||
472 | static Sema::TemplateDeductionResult DeduceNonTypeTemplateArgument( | |||
473 | Sema &S, TemplateParameterList *TemplateParams, | |||
474 | const NonTypeTemplateParmDecl *NTTP, Expr *Value, TemplateDeductionInfo &Info, | |||
475 | SmallVectorImpl<DeducedTemplateArgument> &Deduced) { | |||
476 | return DeduceNonTypeTemplateArgument(S, TemplateParams, NTTP, | |||
477 | DeducedTemplateArgument(Value), | |||
478 | Value->getType(), Info, Deduced); | |||
479 | } | |||
480 | ||||
481 | /// Deduce the value of the given non-type template parameter | |||
482 | /// from the given declaration. | |||
483 | /// | |||
484 | /// \returns true if deduction succeeded, false otherwise. | |||
485 | static Sema::TemplateDeductionResult DeduceNonTypeTemplateArgument( | |||
486 | Sema &S, TemplateParameterList *TemplateParams, | |||
487 | const NonTypeTemplateParmDecl *NTTP, ValueDecl *D, QualType T, | |||
488 | TemplateDeductionInfo &Info, | |||
489 | SmallVectorImpl<DeducedTemplateArgument> &Deduced) { | |||
490 | D = D ? cast<ValueDecl>(D->getCanonicalDecl()) : nullptr; | |||
491 | TemplateArgument New(D, T); | |||
492 | return DeduceNonTypeTemplateArgument( | |||
493 | S, TemplateParams, NTTP, DeducedTemplateArgument(New), T, Info, Deduced); | |||
494 | } | |||
495 | ||||
496 | static Sema::TemplateDeductionResult | |||
497 | DeduceTemplateArguments(Sema &S, | |||
498 | TemplateParameterList *TemplateParams, | |||
499 | TemplateName Param, | |||
500 | TemplateName Arg, | |||
501 | TemplateDeductionInfo &Info, | |||
502 | SmallVectorImpl<DeducedTemplateArgument> &Deduced) { | |||
503 | TemplateDecl *ParamDecl = Param.getAsTemplateDecl(); | |||
504 | if (!ParamDecl) { | |||
505 | // The parameter type is dependent and is not a template template parameter, | |||
506 | // so there is nothing that we can deduce. | |||
507 | return Sema::TDK_Success; | |||
508 | } | |||
509 | ||||
510 | if (TemplateTemplateParmDecl *TempParam | |||
511 | = dyn_cast<TemplateTemplateParmDecl>(ParamDecl)) { | |||
512 | // If we're not deducing at this depth, there's nothing to deduce. | |||
513 | if (TempParam->getDepth() != Info.getDeducedDepth()) | |||
514 | return Sema::TDK_Success; | |||
515 | ||||
516 | DeducedTemplateArgument NewDeduced(S.Context.getCanonicalTemplateName(Arg)); | |||
517 | DeducedTemplateArgument Result = checkDeducedTemplateArguments(S.Context, | |||
518 | Deduced[TempParam->getIndex()], | |||
519 | NewDeduced); | |||
520 | if (Result.isNull()) { | |||
521 | Info.Param = TempParam; | |||
522 | Info.FirstArg = Deduced[TempParam->getIndex()]; | |||
523 | Info.SecondArg = NewDeduced; | |||
524 | return Sema::TDK_Inconsistent; | |||
525 | } | |||
526 | ||||
527 | Deduced[TempParam->getIndex()] = Result; | |||
528 | return Sema::TDK_Success; | |||
529 | } | |||
530 | ||||
531 | // Verify that the two template names are equivalent. | |||
532 | if (S.Context.hasSameTemplateName(Param, Arg)) | |||
533 | return Sema::TDK_Success; | |||
534 | ||||
535 | // Mismatch of non-dependent template parameter to argument. | |||
536 | Info.FirstArg = TemplateArgument(Param); | |||
537 | Info.SecondArg = TemplateArgument(Arg); | |||
538 | return Sema::TDK_NonDeducedMismatch; | |||
539 | } | |||
540 | ||||
541 | /// Deduce the template arguments by comparing the template parameter | |||
542 | /// type (which is a template-id) with the template argument type. | |||
543 | /// | |||
544 | /// \param S the Sema | |||
545 | /// | |||
546 | /// \param TemplateParams the template parameters that we are deducing | |||
547 | /// | |||
548 | /// \param Param the parameter type | |||
549 | /// | |||
550 | /// \param Arg the argument type | |||
551 | /// | |||
552 | /// \param Info information about the template argument deduction itself | |||
553 | /// | |||
554 | /// \param Deduced the deduced template arguments | |||
555 | /// | |||
556 | /// \returns the result of template argument deduction so far. Note that a | |||
557 | /// "success" result means that template argument deduction has not yet failed, | |||
558 | /// but it may still fail, later, for other reasons. | |||
559 | static Sema::TemplateDeductionResult | |||
560 | DeduceTemplateArguments(Sema &S, | |||
561 | TemplateParameterList *TemplateParams, | |||
562 | const TemplateSpecializationType *Param, | |||
563 | QualType Arg, | |||
564 | TemplateDeductionInfo &Info, | |||
565 | SmallVectorImpl<DeducedTemplateArgument> &Deduced) { | |||
566 | 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-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 566, __PRETTY_FUNCTION__)); | |||
567 | ||||
568 | // Treat an injected-class-name as its underlying template-id. | |||
569 | if (auto *Injected = dyn_cast<InjectedClassNameType>(Arg)) | |||
570 | Arg = Injected->getInjectedSpecializationType(); | |||
571 | ||||
572 | // Check whether the template argument is a dependent template-id. | |||
573 | if (const TemplateSpecializationType *SpecArg | |||
574 | = dyn_cast<TemplateSpecializationType>(Arg)) { | |||
575 | // Perform template argument deduction for the template name. | |||
576 | if (Sema::TemplateDeductionResult Result | |||
577 | = DeduceTemplateArguments(S, TemplateParams, | |||
578 | Param->getTemplateName(), | |||
579 | SpecArg->getTemplateName(), | |||
580 | Info, Deduced)) | |||
581 | return Result; | |||
582 | ||||
583 | ||||
584 | // Perform template argument deduction on each template | |||
585 | // argument. Ignore any missing/extra arguments, since they could be | |||
586 | // filled in by default arguments. | |||
587 | return DeduceTemplateArguments(S, TemplateParams, | |||
588 | Param->template_arguments(), | |||
589 | SpecArg->template_arguments(), Info, Deduced, | |||
590 | /*NumberOfArgumentsMustMatch=*/false); | |||
591 | } | |||
592 | ||||
593 | // If the argument type is a class template specialization, we | |||
594 | // perform template argument deduction using its template | |||
595 | // arguments. | |||
596 | const RecordType *RecordArg = dyn_cast<RecordType>(Arg); | |||
597 | if (!RecordArg) { | |||
598 | Info.FirstArg = TemplateArgument(QualType(Param, 0)); | |||
599 | Info.SecondArg = TemplateArgument(Arg); | |||
600 | return Sema::TDK_NonDeducedMismatch; | |||
601 | } | |||
602 | ||||
603 | ClassTemplateSpecializationDecl *SpecArg | |||
604 | = dyn_cast<ClassTemplateSpecializationDecl>(RecordArg->getDecl()); | |||
605 | if (!SpecArg) { | |||
606 | Info.FirstArg = TemplateArgument(QualType(Param, 0)); | |||
607 | Info.SecondArg = TemplateArgument(Arg); | |||
608 | return Sema::TDK_NonDeducedMismatch; | |||
609 | } | |||
610 | ||||
611 | // Perform template argument deduction for the template name. | |||
612 | if (Sema::TemplateDeductionResult Result | |||
613 | = DeduceTemplateArguments(S, | |||
614 | TemplateParams, | |||
615 | Param->getTemplateName(), | |||
616 | TemplateName(SpecArg->getSpecializedTemplate()), | |||
617 | Info, Deduced)) | |||
618 | return Result; | |||
619 | ||||
620 | // Perform template argument deduction for the template arguments. | |||
621 | return DeduceTemplateArguments(S, TemplateParams, Param->template_arguments(), | |||
622 | SpecArg->getTemplateArgs().asArray(), Info, | |||
623 | Deduced, /*NumberOfArgumentsMustMatch=*/true); | |||
624 | } | |||
625 | ||||
626 | /// Determines whether the given type is an opaque type that | |||
627 | /// might be more qualified when instantiated. | |||
628 | static bool IsPossiblyOpaquelyQualifiedType(QualType T) { | |||
629 | switch (T->getTypeClass()) { | |||
630 | case Type::TypeOfExpr: | |||
631 | case Type::TypeOf: | |||
632 | case Type::DependentName: | |||
633 | case Type::Decltype: | |||
634 | case Type::UnresolvedUsing: | |||
635 | case Type::TemplateTypeParm: | |||
636 | return true; | |||
637 | ||||
638 | case Type::ConstantArray: | |||
639 | case Type::IncompleteArray: | |||
640 | case Type::VariableArray: | |||
641 | case Type::DependentSizedArray: | |||
642 | return IsPossiblyOpaquelyQualifiedType( | |||
643 | cast<ArrayType>(T)->getElementType()); | |||
644 | ||||
645 | default: | |||
646 | return false; | |||
647 | } | |||
648 | } | |||
649 | ||||
650 | /// Helper function to build a TemplateParameter when we don't | |||
651 | /// know its type statically. | |||
652 | static TemplateParameter makeTemplateParameter(Decl *D) { | |||
653 | if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(D)) | |||
654 | return TemplateParameter(TTP); | |||
655 | if (NonTypeTemplateParmDecl *NTTP = dyn_cast<NonTypeTemplateParmDecl>(D)) | |||
656 | return TemplateParameter(NTTP); | |||
657 | ||||
658 | return TemplateParameter(cast<TemplateTemplateParmDecl>(D)); | |||
659 | } | |||
660 | ||||
661 | /// A pack that we're currently deducing. | |||
662 | struct clang::DeducedPack { | |||
663 | // The index of the pack. | |||
664 | unsigned Index; | |||
665 | ||||
666 | // The old value of the pack before we started deducing it. | |||
667 | DeducedTemplateArgument Saved; | |||
668 | ||||
669 | // A deferred value of this pack from an inner deduction, that couldn't be | |||
670 | // deduced because this deduction hadn't happened yet. | |||
671 | DeducedTemplateArgument DeferredDeduction; | |||
672 | ||||
673 | // The new value of the pack. | |||
674 | SmallVector<DeducedTemplateArgument, 4> New; | |||
675 | ||||
676 | // The outer deduction for this pack, if any. | |||
677 | DeducedPack *Outer = nullptr; | |||
678 | ||||
679 | DeducedPack(unsigned Index) : Index(Index) {} | |||
680 | }; | |||
681 | ||||
682 | namespace { | |||
683 | ||||
684 | /// A scope in which we're performing pack deduction. | |||
685 | class PackDeductionScope { | |||
686 | public: | |||
687 | /// Prepare to deduce the packs named within Pattern. | |||
688 | PackDeductionScope(Sema &S, TemplateParameterList *TemplateParams, | |||
689 | SmallVectorImpl<DeducedTemplateArgument> &Deduced, | |||
690 | TemplateDeductionInfo &Info, TemplateArgument Pattern) | |||
691 | : S(S), TemplateParams(TemplateParams), Deduced(Deduced), Info(Info) { | |||
692 | unsigned NumNamedPacks = addPacks(Pattern); | |||
693 | finishConstruction(NumNamedPacks); | |||
694 | } | |||
695 | ||||
696 | /// Prepare to directly deduce arguments of the parameter with index \p Index. | |||
697 | PackDeductionScope(Sema &S, TemplateParameterList *TemplateParams, | |||
698 | SmallVectorImpl<DeducedTemplateArgument> &Deduced, | |||
699 | TemplateDeductionInfo &Info, unsigned Index) | |||
700 | : S(S), TemplateParams(TemplateParams), Deduced(Deduced), Info(Info) { | |||
701 | addPack(Index); | |||
702 | finishConstruction(1); | |||
703 | } | |||
704 | ||||
705 | private: | |||
706 | void addPack(unsigned Index) { | |||
707 | // Save the deduced template argument for the parameter pack expanded | |||
708 | // by this pack expansion, then clear out the deduction. | |||
709 | DeducedPack Pack(Index); | |||
710 | Pack.Saved = Deduced[Index]; | |||
711 | Deduced[Index] = TemplateArgument(); | |||
712 | ||||
713 | // FIXME: What if we encounter multiple packs with different numbers of | |||
714 | // pre-expanded expansions? (This should already have been diagnosed | |||
715 | // during substitution.) | |||
716 | if (Optional<unsigned> ExpandedPackExpansions = | |||
717 | getExpandedPackSize(TemplateParams->getParam(Index))) | |||
718 | FixedNumExpansions = ExpandedPackExpansions; | |||
719 | ||||
720 | Packs.push_back(Pack); | |||
721 | } | |||
722 | ||||
723 | unsigned addPacks(TemplateArgument Pattern) { | |||
724 | // Compute the set of template parameter indices that correspond to | |||
725 | // parameter packs expanded by the pack expansion. | |||
726 | llvm::SmallBitVector SawIndices(TemplateParams->size()); | |||
727 | llvm::SmallVector<TemplateArgument, 4> ExtraDeductions; | |||
728 | ||||
729 | auto AddPack = [&](unsigned Index) { | |||
730 | if (SawIndices[Index]) | |||
731 | return; | |||
732 | SawIndices[Index] = true; | |||
733 | addPack(Index); | |||
734 | ||||
735 | // Deducing a parameter pack that is a pack expansion also constrains the | |||
736 | // packs appearing in that parameter to have the same deduced arity. Also, | |||
737 | // in C++17 onwards, deducing a non-type template parameter deduces its | |||
738 | // type, so we need to collect the pending deduced values for those packs. | |||
739 | if (auto *NTTP = dyn_cast<NonTypeTemplateParmDecl>( | |||
740 | TemplateParams->getParam(Index))) { | |||
741 | if (!NTTP->isExpandedParameterPack()) | |||
742 | if (auto *Expansion = dyn_cast<PackExpansionType>(NTTP->getType())) | |||
743 | ExtraDeductions.push_back(Expansion->getPattern()); | |||
744 | } | |||
745 | // FIXME: Also collect the unexpanded packs in any type and template | |||
746 | // parameter packs that are pack expansions. | |||
747 | }; | |||
748 | ||||
749 | auto Collect = [&](TemplateArgument Pattern) { | |||
750 | SmallVector<UnexpandedParameterPack, 2> Unexpanded; | |||
751 | S.collectUnexpandedParameterPacks(Pattern, Unexpanded); | |||
752 | for (unsigned I = 0, N = Unexpanded.size(); I != N; ++I) { | |||
753 | unsigned Depth, Index; | |||
754 | std::tie(Depth, Index) = getDepthAndIndex(Unexpanded[I]); | |||
755 | if (Depth == Info.getDeducedDepth()) | |||
756 | AddPack(Index); | |||
757 | } | |||
758 | }; | |||
759 | ||||
760 | // Look for unexpanded packs in the pattern. | |||
761 | Collect(Pattern); | |||
762 | 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-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 762, __PRETTY_FUNCTION__)); | |||
763 | ||||
764 | unsigned NumNamedPacks = Packs.size(); | |||
765 | ||||
766 | // Also look for unexpanded packs that are indirectly deduced by deducing | |||
767 | // the sizes of the packs in this pattern. | |||
768 | while (!ExtraDeductions.empty()) | |||
769 | Collect(ExtraDeductions.pop_back_val()); | |||
770 | ||||
771 | return NumNamedPacks; | |||
772 | } | |||
773 | ||||
774 | void finishConstruction(unsigned NumNamedPacks) { | |||
775 | // Dig out the partially-substituted pack, if there is one. | |||
776 | const TemplateArgument *PartialPackArgs = nullptr; | |||
777 | unsigned NumPartialPackArgs = 0; | |||
778 | std::pair<unsigned, unsigned> PartialPackDepthIndex(-1u, -1u); | |||
779 | if (auto *Scope = S.CurrentInstantiationScope) | |||
780 | if (auto *Partial = Scope->getPartiallySubstitutedPack( | |||
781 | &PartialPackArgs, &NumPartialPackArgs)) | |||
782 | PartialPackDepthIndex = getDepthAndIndex(Partial); | |||
783 | ||||
784 | // This pack expansion will have been partially or fully expanded if | |||
785 | // it only names explicitly-specified parameter packs (including the | |||
786 | // partially-substituted one, if any). | |||
787 | bool IsExpanded = true; | |||
788 | for (unsigned I = 0; I != NumNamedPacks; ++I) { | |||
789 | if (Packs[I].Index >= Info.getNumExplicitArgs()) { | |||
790 | IsExpanded = false; | |||
791 | IsPartiallyExpanded = false; | |||
792 | break; | |||
793 | } | |||
794 | if (PartialPackDepthIndex == | |||
795 | std::make_pair(Info.getDeducedDepth(), Packs[I].Index)) { | |||
796 | IsPartiallyExpanded = true; | |||
797 | } | |||
798 | } | |||
799 | ||||
800 | // Skip over the pack elements that were expanded into separate arguments. | |||
801 | // If we partially expanded, this is the number of partial arguments. | |||
802 | if (IsPartiallyExpanded) | |||
803 | PackElements += NumPartialPackArgs; | |||
804 | else if (IsExpanded) | |||
805 | PackElements += *FixedNumExpansions; | |||
806 | ||||
807 | for (auto &Pack : Packs) { | |||
808 | if (Info.PendingDeducedPacks.size() > Pack.Index) | |||
809 | Pack.Outer = Info.PendingDeducedPacks[Pack.Index]; | |||
810 | else | |||
811 | Info.PendingDeducedPacks.resize(Pack.Index + 1); | |||
812 | Info.PendingDeducedPacks[Pack.Index] = &Pack; | |||
813 | ||||
814 | if (PartialPackDepthIndex == | |||
815 | std::make_pair(Info.getDeducedDepth(), Pack.Index)) { | |||
816 | Pack.New.append(PartialPackArgs, PartialPackArgs + NumPartialPackArgs); | |||
817 | // We pre-populate the deduced value of the partially-substituted | |||
818 | // pack with the specified value. This is not entirely correct: the | |||
819 | // value is supposed to have been substituted, not deduced, but the | |||
820 | // cases where this is observable require an exact type match anyway. | |||
821 | // | |||
822 | // FIXME: If we could represent a "depth i, index j, pack elem k" | |||
823 | // parameter, we could substitute the partially-substituted pack | |||
824 | // everywhere and avoid this. | |||
825 | if (!IsPartiallyExpanded) | |||
826 | Deduced[Pack.Index] = Pack.New[PackElements]; | |||
827 | } | |||
828 | } | |||
829 | } | |||
830 | ||||
831 | public: | |||
832 | ~PackDeductionScope() { | |||
833 | for (auto &Pack : Packs) | |||
834 | Info.PendingDeducedPacks[Pack.Index] = Pack.Outer; | |||
835 | } | |||
836 | ||||
837 | /// Determine whether this pack has already been partially expanded into a | |||
838 | /// sequence of (prior) function parameters / template arguments. | |||
839 | bool isPartiallyExpanded() { return IsPartiallyExpanded; } | |||
840 | ||||
841 | /// Determine whether this pack expansion scope has a known, fixed arity. | |||
842 | /// This happens if it involves a pack from an outer template that has | |||
843 | /// (notionally) already been expanded. | |||
844 | bool hasFixedArity() { return FixedNumExpansions.hasValue(); } | |||
845 | ||||
846 | /// Determine whether the next element of the argument is still part of this | |||
847 | /// pack. This is the case unless the pack is already expanded to a fixed | |||
848 | /// length. | |||
849 | bool hasNextElement() { | |||
850 | return !FixedNumExpansions || *FixedNumExpansions > PackElements; | |||
851 | } | |||
852 | ||||
853 | /// Move to deducing the next element in each pack that is being deduced. | |||
854 | void nextPackElement() { | |||
855 | // Capture the deduced template arguments for each parameter pack expanded | |||
856 | // by this pack expansion, add them to the list of arguments we've deduced | |||
857 | // for that pack, then clear out the deduced argument. | |||
858 | for (auto &Pack : Packs) { | |||
859 | DeducedTemplateArgument &DeducedArg = Deduced[Pack.Index]; | |||
860 | if (!Pack.New.empty() || !DeducedArg.isNull()) { | |||
861 | while (Pack.New.size() < PackElements) | |||
862 | Pack.New.push_back(DeducedTemplateArgument()); | |||
863 | if (Pack.New.size() == PackElements) | |||
864 | Pack.New.push_back(DeducedArg); | |||
865 | else | |||
866 | Pack.New[PackElements] = DeducedArg; | |||
867 | DeducedArg = Pack.New.size() > PackElements + 1 | |||
868 | ? Pack.New[PackElements + 1] | |||
869 | : DeducedTemplateArgument(); | |||
870 | } | |||
871 | } | |||
872 | ++PackElements; | |||
873 | } | |||
874 | ||||
875 | /// Finish template argument deduction for a set of argument packs, | |||
876 | /// producing the argument packs and checking for consistency with prior | |||
877 | /// deductions. | |||
878 | Sema::TemplateDeductionResult finish() { | |||
879 | // Build argument packs for each of the parameter packs expanded by this | |||
880 | // pack expansion. | |||
881 | for (auto &Pack : Packs) { | |||
882 | // Put back the old value for this pack. | |||
883 | Deduced[Pack.Index] = Pack.Saved; | |||
884 | ||||
885 | // Always make sure the size of this pack is correct, even if we didn't | |||
886 | // deduce any values for it. | |||
887 | // | |||
888 | // FIXME: This isn't required by the normative wording, but substitution | |||
889 | // and post-substitution checking will always fail if the arity of any | |||
890 | // pack is not equal to the number of elements we processed. (Either that | |||
891 | // or something else has gone *very* wrong.) We're permitted to skip any | |||
892 | // hard errors from those follow-on steps by the intent (but not the | |||
893 | // wording) of C++ [temp.inst]p8: | |||
894 | // | |||
895 | // If the function selected by overload resolution can be determined | |||
896 | // without instantiating a class template definition, it is unspecified | |||
897 | // whether that instantiation actually takes place | |||
898 | Pack.New.resize(PackElements); | |||
899 | ||||
900 | // Build or find a new value for this pack. | |||
901 | DeducedTemplateArgument NewPack; | |||
902 | if (Pack.New.empty()) { | |||
903 | // If we deduced an empty argument pack, create it now. | |||
904 | NewPack = DeducedTemplateArgument(TemplateArgument::getEmptyPack()); | |||
905 | } else { | |||
906 | TemplateArgument *ArgumentPack = | |||
907 | new (S.Context) TemplateArgument[Pack.New.size()]; | |||
908 | std::copy(Pack.New.begin(), Pack.New.end(), ArgumentPack); | |||
909 | NewPack = DeducedTemplateArgument( | |||
910 | TemplateArgument(llvm::makeArrayRef(ArgumentPack, Pack.New.size())), | |||
911 | // FIXME: This is wrong, it's possible that some pack elements are | |||
912 | // deduced from an array bound and others are not: | |||
913 | // template<typename ...T, T ...V> void g(const T (&...p)[V]); | |||
914 | // g({1, 2, 3}, {{}, {}}); | |||
915 | // ... should deduce T = {int, size_t (from array bound)}. | |||
916 | Pack.New[0].wasDeducedFromArrayBound()); | |||
917 | } | |||
918 | ||||
919 | // Pick where we're going to put the merged pack. | |||
920 | DeducedTemplateArgument *Loc; | |||
921 | if (Pack.Outer) { | |||
922 | if (Pack.Outer->DeferredDeduction.isNull()) { | |||
923 | // Defer checking this pack until we have a complete pack to compare | |||
924 | // it against. | |||
925 | Pack.Outer->DeferredDeduction = NewPack; | |||
926 | continue; | |||
927 | } | |||
928 | Loc = &Pack.Outer->DeferredDeduction; | |||
929 | } else { | |||
930 | Loc = &Deduced[Pack.Index]; | |||
931 | } | |||
932 | ||||
933 | // Check the new pack matches any previous value. | |||
934 | DeducedTemplateArgument OldPack = *Loc; | |||
935 | DeducedTemplateArgument Result = | |||
936 | checkDeducedTemplateArguments(S.Context, OldPack, NewPack); | |||
937 | ||||
938 | // If we deferred a deduction of this pack, check that one now too. | |||
939 | if (!Result.isNull() && !Pack.DeferredDeduction.isNull()) { | |||
940 | OldPack = Result; | |||
941 | NewPack = Pack.DeferredDeduction; | |||
942 | Result = checkDeducedTemplateArguments(S.Context, OldPack, NewPack); | |||
943 | } | |||
944 | ||||
945 | NamedDecl *Param = TemplateParams->getParam(Pack.Index); | |||
946 | if (Result.isNull()) { | |||
947 | Info.Param = makeTemplateParameter(Param); | |||
948 | Info.FirstArg = OldPack; | |||
949 | Info.SecondArg = NewPack; | |||
950 | return Sema::TDK_Inconsistent; | |||
951 | } | |||
952 | ||||
953 | // If we have a pre-expanded pack and we didn't deduce enough elements | |||
954 | // for it, fail deduction. | |||
955 | if (Optional<unsigned> Expansions = getExpandedPackSize(Param)) { | |||
956 | if (*Expansions != PackElements) { | |||
957 | Info.Param = makeTemplateParameter(Param); | |||
958 | Info.FirstArg = Result; | |||
959 | return Sema::TDK_IncompletePack; | |||
960 | } | |||
961 | } | |||
962 | ||||
963 | *Loc = Result; | |||
964 | } | |||
965 | ||||
966 | return Sema::TDK_Success; | |||
967 | } | |||
968 | ||||
969 | private: | |||
970 | Sema &S; | |||
971 | TemplateParameterList *TemplateParams; | |||
972 | SmallVectorImpl<DeducedTemplateArgument> &Deduced; | |||
973 | TemplateDeductionInfo &Info; | |||
974 | unsigned PackElements = 0; | |||
975 | bool IsPartiallyExpanded = false; | |||
976 | /// The number of expansions, if we have a fully-expanded pack in this scope. | |||
977 | Optional<unsigned> FixedNumExpansions; | |||
978 | ||||
979 | SmallVector<DeducedPack, 2> Packs; | |||
980 | }; | |||
981 | ||||
982 | } // namespace | |||
983 | ||||
984 | /// Deduce the template arguments by comparing the list of parameter | |||
985 | /// types to the list of argument types, as in the parameter-type-lists of | |||
986 | /// function types (C++ [temp.deduct.type]p10). | |||
987 | /// | |||
988 | /// \param S The semantic analysis object within which we are deducing | |||
989 | /// | |||
990 | /// \param TemplateParams The template parameters that we are deducing | |||
991 | /// | |||
992 | /// \param Params The list of parameter types | |||
993 | /// | |||
994 | /// \param NumParams The number of types in \c Params | |||
995 | /// | |||
996 | /// \param Args The list of argument types | |||
997 | /// | |||
998 | /// \param NumArgs The number of types in \c Args | |||
999 | /// | |||
1000 | /// \param Info information about the template argument deduction itself | |||
1001 | /// | |||
1002 | /// \param Deduced the deduced template arguments | |||
1003 | /// | |||
1004 | /// \param TDF bitwise OR of the TemplateDeductionFlags bits that describe | |||
1005 | /// how template argument deduction is performed. | |||
1006 | /// | |||
1007 | /// \param PartialOrdering If true, we are performing template argument | |||
1008 | /// deduction for during partial ordering for a call | |||
1009 | /// (C++0x [temp.deduct.partial]). | |||
1010 | /// | |||
1011 | /// \returns the result of template argument deduction so far. Note that a | |||
1012 | /// "success" result means that template argument deduction has not yet failed, | |||
1013 | /// but it may still fail, later, for other reasons. | |||
1014 | static Sema::TemplateDeductionResult | |||
1015 | DeduceTemplateArguments(Sema &S, | |||
1016 | TemplateParameterList *TemplateParams, | |||
1017 | const QualType *Params, unsigned NumParams, | |||
1018 | const QualType *Args, unsigned NumArgs, | |||
1019 | TemplateDeductionInfo &Info, | |||
1020 | SmallVectorImpl<DeducedTemplateArgument> &Deduced, | |||
1021 | unsigned TDF, | |||
1022 | bool PartialOrdering = false) { | |||
1023 | // C++0x [temp.deduct.type]p10: | |||
1024 | // Similarly, if P has a form that contains (T), then each parameter type | |||
1025 | // Pi of the respective parameter-type- list of P is compared with the | |||
1026 | // corresponding parameter type Ai of the corresponding parameter-type-list | |||
1027 | // of A. [...] | |||
1028 | unsigned ArgIdx = 0, ParamIdx = 0; | |||
1029 | for (; ParamIdx != NumParams; ++ParamIdx) { | |||
1030 | // Check argument types. | |||
1031 | const PackExpansionType *Expansion | |||
1032 | = dyn_cast<PackExpansionType>(Params[ParamIdx]); | |||
1033 | if (!Expansion) { | |||
1034 | // Simple case: compare the parameter and argument types at this point. | |||
1035 | ||||
1036 | // Make sure we have an argument. | |||
1037 | if (ArgIdx >= NumArgs) | |||
1038 | return Sema::TDK_MiscellaneousDeductionFailure; | |||
1039 | ||||
1040 | if (isa<PackExpansionType>(Args[ArgIdx])) { | |||
1041 | // C++0x [temp.deduct.type]p22: | |||
1042 | // If the original function parameter associated with A is a function | |||
1043 | // parameter pack and the function parameter associated with P is not | |||
1044 | // a function parameter pack, then template argument deduction fails. | |||
1045 | return Sema::TDK_MiscellaneousDeductionFailure; | |||
1046 | } | |||
1047 | ||||
1048 | if (Sema::TemplateDeductionResult Result | |||
1049 | = DeduceTemplateArgumentsByTypeMatch(S, TemplateParams, | |||
1050 | Params[ParamIdx], Args[ArgIdx], | |||
1051 | Info, Deduced, TDF, | |||
1052 | PartialOrdering)) | |||
1053 | return Result; | |||
1054 | ||||
1055 | ++ArgIdx; | |||
1056 | continue; | |||
1057 | } | |||
1058 | ||||
1059 | // C++0x [temp.deduct.type]p10: | |||
1060 | // If the parameter-declaration corresponding to Pi is a function | |||
1061 | // parameter pack, then the type of its declarator- id is compared with | |||
1062 | // each remaining parameter type in the parameter-type-list of A. Each | |||
1063 | // comparison deduces template arguments for subsequent positions in the | |||
1064 | // template parameter packs expanded by the function parameter pack. | |||
1065 | ||||
1066 | QualType Pattern = Expansion->getPattern(); | |||
1067 | PackDeductionScope PackScope(S, TemplateParams, Deduced, Info, Pattern); | |||
1068 | ||||
1069 | // A pack scope with fixed arity is not really a pack any more, so is not | |||
1070 | // a non-deduced context. | |||
1071 | if (ParamIdx + 1 == NumParams || PackScope.hasFixedArity()) { | |||
1072 | for (; ArgIdx < NumArgs && PackScope.hasNextElement(); ++ArgIdx) { | |||
1073 | // Deduce template arguments from the pattern. | |||
1074 | if (Sema::TemplateDeductionResult Result | |||
1075 | = DeduceTemplateArgumentsByTypeMatch(S, TemplateParams, Pattern, | |||
1076 | Args[ArgIdx], Info, Deduced, | |||
1077 | TDF, PartialOrdering)) | |||
1078 | return Result; | |||
1079 | ||||
1080 | PackScope.nextPackElement(); | |||
1081 | } | |||
1082 | } else { | |||
1083 | // C++0x [temp.deduct.type]p5: | |||
1084 | // The non-deduced contexts are: | |||
1085 | // - A function parameter pack that does not occur at the end of the | |||
1086 | // parameter-declaration-clause. | |||
1087 | // | |||
1088 | // FIXME: There is no wording to say what we should do in this case. We | |||
1089 | // choose to resolve this by applying the same rule that is applied for a | |||
1090 | // function call: that is, deduce all contained packs to their | |||
1091 | // explicitly-specified values (or to <> if there is no such value). | |||
1092 | // | |||
1093 | // This is seemingly-arbitrarily different from the case of a template-id | |||
1094 | // with a non-trailing pack-expansion in its arguments, which renders the | |||
1095 | // entire template-argument-list a non-deduced context. | |||
1096 | ||||
1097 | // If the parameter type contains an explicitly-specified pack that we | |||
1098 | // could not expand, skip the number of parameters notionally created | |||
1099 | // by the expansion. | |||
1100 | Optional<unsigned> NumExpansions = Expansion->getNumExpansions(); | |||
1101 | if (NumExpansions && !PackScope.isPartiallyExpanded()) { | |||
1102 | for (unsigned I = 0; I != *NumExpansions && ArgIdx < NumArgs; | |||
1103 | ++I, ++ArgIdx) | |||
1104 | PackScope.nextPackElement(); | |||
1105 | } | |||
1106 | } | |||
1107 | ||||
1108 | // Build argument packs for each of the parameter packs expanded by this | |||
1109 | // pack expansion. | |||
1110 | if (auto Result = PackScope.finish()) | |||
1111 | return Result; | |||
1112 | } | |||
1113 | ||||
1114 | // Make sure we don't have any extra arguments. | |||
1115 | if (ArgIdx < NumArgs) | |||
1116 | return Sema::TDK_MiscellaneousDeductionFailure; | |||
1117 | ||||
1118 | return Sema::TDK_Success; | |||
1119 | } | |||
1120 | ||||
1121 | /// Determine whether the parameter has qualifiers that the argument | |||
1122 | /// lacks. Put another way, determine whether there is no way to add | |||
1123 | /// a deduced set of qualifiers to the ParamType that would result in | |||
1124 | /// its qualifiers matching those of the ArgType. | |||
1125 | static bool hasInconsistentOrSupersetQualifiersOf(QualType ParamType, | |||
1126 | QualType ArgType) { | |||
1127 | Qualifiers ParamQs = ParamType.getQualifiers(); | |||
1128 | Qualifiers ArgQs = ArgType.getQualifiers(); | |||
1129 | ||||
1130 | if (ParamQs == ArgQs) | |||
1131 | return false; | |||
1132 | ||||
1133 | // Mismatched (but not missing) Objective-C GC attributes. | |||
1134 | if (ParamQs.getObjCGCAttr() != ArgQs.getObjCGCAttr() && | |||
1135 | ParamQs.hasObjCGCAttr()) | |||
1136 | return true; | |||
1137 | ||||
1138 | // Mismatched (but not missing) address spaces. | |||
1139 | if (ParamQs.getAddressSpace() != ArgQs.getAddressSpace() && | |||
1140 | ParamQs.hasAddressSpace()) | |||
1141 | return true; | |||
1142 | ||||
1143 | // Mismatched (but not missing) Objective-C lifetime qualifiers. | |||
1144 | if (ParamQs.getObjCLifetime() != ArgQs.getObjCLifetime() && | |||
1145 | ParamQs.hasObjCLifetime()) | |||
1146 | return true; | |||
1147 | ||||
1148 | // CVR qualifiers inconsistent or a superset. | |||
1149 | return (ParamQs.getCVRQualifiers() & ~ArgQs.getCVRQualifiers()) != 0; | |||
1150 | } | |||
1151 | ||||
1152 | /// Compare types for equality with respect to possibly compatible | |||
1153 | /// function types (noreturn adjustment, implicit calling conventions). If any | |||
1154 | /// of parameter and argument is not a function, just perform type comparison. | |||
1155 | /// | |||
1156 | /// \param Param the template parameter type. | |||
1157 | /// | |||
1158 | /// \param Arg the argument type. | |||
1159 | bool Sema::isSameOrCompatibleFunctionType(CanQualType Param, | |||
1160 | CanQualType Arg) { | |||
1161 | const FunctionType *ParamFunction = Param->getAs<FunctionType>(), | |||
1162 | *ArgFunction = Arg->getAs<FunctionType>(); | |||
1163 | ||||
1164 | // Just compare if not functions. | |||
1165 | if (!ParamFunction || !ArgFunction) | |||
1166 | return Param == Arg; | |||
1167 | ||||
1168 | // Noreturn and noexcept adjustment. | |||
1169 | QualType AdjustedParam; | |||
1170 | if (IsFunctionConversion(Param, Arg, AdjustedParam)) | |||
1171 | return Arg == Context.getCanonicalType(AdjustedParam); | |||
1172 | ||||
1173 | // FIXME: Compatible calling conventions. | |||
1174 | ||||
1175 | return Param == Arg; | |||
1176 | } | |||
1177 | ||||
1178 | /// Get the index of the first template parameter that was originally from the | |||
1179 | /// innermost template-parameter-list. This is 0 except when we concatenate | |||
1180 | /// the template parameter lists of a class template and a constructor template | |||
1181 | /// when forming an implicit deduction guide. | |||
1182 | static unsigned getFirstInnerIndex(FunctionTemplateDecl *FTD) { | |||
1183 | auto *Guide = dyn_cast<CXXDeductionGuideDecl>(FTD->getTemplatedDecl()); | |||
1184 | if (!Guide || !Guide->isImplicit()) | |||
1185 | return 0; | |||
1186 | return Guide->getDeducedTemplate()->getTemplateParameters()->size(); | |||
1187 | } | |||
1188 | ||||
1189 | /// Determine whether a type denotes a forwarding reference. | |||
1190 | static bool isForwardingReference(QualType Param, unsigned FirstInnerIndex) { | |||
1191 | // C++1z [temp.deduct.call]p3: | |||
1192 | // A forwarding reference is an rvalue reference to a cv-unqualified | |||
1193 | // template parameter that does not represent a template parameter of a | |||
1194 | // class template. | |||
1195 | if (auto *ParamRef = Param->getAs<RValueReferenceType>()) { | |||
1196 | if (ParamRef->getPointeeType().getQualifiers()) | |||
1197 | return false; | |||
1198 | auto *TypeParm = ParamRef->getPointeeType()->getAs<TemplateTypeParmType>(); | |||
1199 | return TypeParm && TypeParm->getIndex() >= FirstInnerIndex; | |||
1200 | } | |||
1201 | return false; | |||
1202 | } | |||
1203 | ||||
1204 | /// Attempt to deduce the template arguments by checking the base types | |||
1205 | /// according to (C++20 [temp.deduct.call] p4b3. | |||
1206 | /// | |||
1207 | /// \param S the semantic analysis object within which we are deducing. | |||
1208 | /// | |||
1209 | /// \param RecordT the top level record object we are deducing against. | |||
1210 | /// | |||
1211 | /// \param TemplateParams the template parameters that we are deducing. | |||
1212 | /// | |||
1213 | /// \param SpecParam the template specialization parameter type. | |||
1214 | /// | |||
1215 | /// \param Info information about the template argument deduction itself. | |||
1216 | /// | |||
1217 | /// \param Deduced the deduced template arguments. | |||
1218 | /// | |||
1219 | /// \returns the result of template argument deduction with the bases. "invalid" | |||
1220 | /// means no matches, "success" found a single item, and the | |||
1221 | /// "MiscellaneousDeductionFailure" result happens when the match is ambiguous. | |||
1222 | static Sema::TemplateDeductionResult DeduceTemplateBases( | |||
1223 | Sema &S, const RecordType *RecordT, TemplateParameterList *TemplateParams, | |||
1224 | const TemplateSpecializationType *SpecParam, TemplateDeductionInfo &Info, | |||
1225 | SmallVectorImpl<DeducedTemplateArgument> &Deduced) { | |||
1226 | // C++14 [temp.deduct.call] p4b3: | |||
1227 | // If P is a class and P has the form simple-template-id, then the | |||
1228 | // transformed A can be a derived class of the deduced A. Likewise if | |||
1229 | // P is a pointer to a class of the form simple-template-id, the | |||
1230 | // transformed A can be a pointer to a derived class pointed to by the | |||
1231 | // deduced A. However, if there is a class C that is a (direct or | |||
1232 | // indirect) base class of D and derived (directly or indirectly) from a | |||
1233 | // class B and that would be a valid deduced A, the deduced A cannot be | |||
1234 | // B or pointer to B, respectively. | |||
1235 | // | |||
1236 | // These alternatives are considered only if type deduction would | |||
1237 | // otherwise fail. If they yield more than one possible deduced A, the | |||
1238 | // type deduction fails. | |||
1239 | ||||
1240 | // Use a breadth-first search through the bases to collect the set of | |||
1241 | // successful matches. Visited contains the set of nodes we have already | |||
1242 | // visited, while ToVisit is our stack of records that we still need to | |||
1243 | // visit. Matches contains a list of matches that have yet to be | |||
1244 | // disqualified. | |||
1245 | llvm::SmallPtrSet<const RecordType *, 8> Visited; | |||
1246 | SmallVector<const RecordType *, 8> ToVisit; | |||
1247 | // We iterate over this later, so we have to use MapVector to ensure | |||
1248 | // determinism. | |||
1249 | llvm::MapVector<const RecordType *, SmallVector<DeducedTemplateArgument, 8>> | |||
1250 | Matches; | |||
1251 | ||||
1252 | auto AddBases = [&Visited, &ToVisit](const RecordType *RT) { | |||
1253 | CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl()); | |||
1254 | for (const auto &Base : RD->bases()) { | |||
1255 | 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-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 1256, __PRETTY_FUNCTION__)) | |||
1256 | "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-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 1256, __PRETTY_FUNCTION__)); | |||
1257 | const RecordType *RT = Base.getType()->getAs<RecordType>(); | |||
1258 | if (Visited.insert(RT).second) | |||
1259 | ToVisit.push_back(Base.getType()->getAs<RecordType>()); | |||
1260 | } | |||
1261 | }; | |||
1262 | ||||
1263 | // Set up the loop by adding all the bases. | |||
1264 | AddBases(RecordT); | |||
1265 | ||||
1266 | // Search each path of bases until we either run into a successful match | |||
1267 | // (where all bases of it are invalid), or we run out of bases. | |||
1268 | while (!ToVisit.empty()) { | |||
1269 | const RecordType *NextT = ToVisit.pop_back_val(); | |||
1270 | ||||
1271 | SmallVector<DeducedTemplateArgument, 8> DeducedCopy(Deduced.begin(), | |||
1272 | Deduced.end()); | |||
1273 | TemplateDeductionInfo BaseInfo(TemplateDeductionInfo::ForBase, Info); | |||
1274 | Sema::TemplateDeductionResult BaseResult = | |||
1275 | DeduceTemplateArguments(S, TemplateParams, SpecParam, | |||
1276 | QualType(NextT, 0), BaseInfo, DeducedCopy); | |||
1277 | ||||
1278 | // If this was a successful deduction, add it to the list of matches, | |||
1279 | // otherwise we need to continue searching its bases. | |||
1280 | if (BaseResult == Sema::TDK_Success) | |||
1281 | Matches.insert({NextT, DeducedCopy}); | |||
1282 | else | |||
1283 | AddBases(NextT); | |||
1284 | } | |||
1285 | ||||
1286 | // At this point, 'Matches' contains a list of seemingly valid bases, however | |||
1287 | // in the event that we have more than 1 match, it is possible that the base | |||
1288 | // of one of the matches might be disqualified for being a base of another | |||
1289 | // valid match. We can count on cyclical instantiations being invalid to | |||
1290 | // simplify the disqualifications. That is, if A & B are both matches, and B | |||
1291 | // inherits from A (disqualifying A), we know that A cannot inherit from B. | |||
1292 | if (Matches.size() > 1) { | |||
1293 | Visited.clear(); | |||
1294 | for (const auto &Match : Matches) | |||
1295 | AddBases(Match.first); | |||
1296 | ||||
1297 | // We can give up once we have a single item (or have run out of things to | |||
1298 | // search) since cyclical inheritence isn't valid. | |||
1299 | while (Matches.size() > 1 && !ToVisit.empty()) { | |||
1300 | const RecordType *NextT = ToVisit.pop_back_val(); | |||
1301 | Matches.erase(NextT); | |||
1302 | ||||
1303 | // Always add all bases, since the inheritence tree can contain | |||
1304 | // disqualifications for multiple matches. | |||
1305 | AddBases(NextT); | |||
1306 | } | |||
1307 | } | |||
1308 | ||||
1309 | if (Matches.empty()) | |||
1310 | return Sema::TDK_Invalid; | |||
1311 | if (Matches.size() > 1) | |||
1312 | return Sema::TDK_MiscellaneousDeductionFailure; | |||
1313 | ||||
1314 | std::swap(Matches.front().second, Deduced); | |||
1315 | return Sema::TDK_Success; | |||
1316 | } | |||
1317 | ||||
1318 | /// Deduce the template arguments by comparing the parameter type and | |||
1319 | /// the argument type (C++ [temp.deduct.type]). | |||
1320 | /// | |||
1321 | /// \param S the semantic analysis object within which we are deducing | |||
1322 | /// | |||
1323 | /// \param TemplateParams the template parameters that we are deducing | |||
1324 | /// | |||
1325 | /// \param ParamIn the parameter type | |||
1326 | /// | |||
1327 | /// \param ArgIn the argument type | |||
1328 | /// | |||
1329 | /// \param Info information about the template argument deduction itself | |||
1330 | /// | |||
1331 | /// \param Deduced the deduced template arguments | |||
1332 | /// | |||
1333 | /// \param TDF bitwise OR of the TemplateDeductionFlags bits that describe | |||
1334 | /// how template argument deduction is performed. | |||
1335 | /// | |||
1336 | /// \param PartialOrdering Whether we're performing template argument deduction | |||
1337 | /// in the context of partial ordering (C++0x [temp.deduct.partial]). | |||
1338 | /// | |||
1339 | /// \returns the result of template argument deduction so far. Note that a | |||
1340 | /// "success" result means that template argument deduction has not yet failed, | |||
1341 | /// but it may still fail, later, for other reasons. | |||
1342 | static Sema::TemplateDeductionResult | |||
1343 | DeduceTemplateArgumentsByTypeMatch(Sema &S, | |||
1344 | TemplateParameterList *TemplateParams, | |||
1345 | QualType ParamIn, QualType ArgIn, | |||
1346 | TemplateDeductionInfo &Info, | |||
1347 | SmallVectorImpl<DeducedTemplateArgument> &Deduced, | |||
1348 | unsigned TDF, | |||
1349 | bool PartialOrdering, | |||
1350 | bool DeducedFromArrayBound) { | |||
1351 | // We only want to look at the canonical types, since typedefs and | |||
1352 | // sugar are not part of template argument deduction. | |||
1353 | QualType Param = S.Context.getCanonicalType(ParamIn); | |||
1354 | QualType Arg = S.Context.getCanonicalType(ArgIn); | |||
1355 | ||||
1356 | // If the argument type is a pack expansion, look at its pattern. | |||
1357 | // This isn't explicitly called out | |||
1358 | if (const PackExpansionType *ArgExpansion | |||
1359 | = dyn_cast<PackExpansionType>(Arg)) | |||
1360 | Arg = ArgExpansion->getPattern(); | |||
1361 | ||||
1362 | if (PartialOrdering) { | |||
1363 | // C++11 [temp.deduct.partial]p5: | |||
1364 | // Before the partial ordering is done, certain transformations are | |||
1365 | // performed on the types used for partial ordering: | |||
1366 | // - If P is a reference type, P is replaced by the type referred to. | |||
1367 | const ReferenceType *ParamRef = Param->getAs<ReferenceType>(); | |||
1368 | if (ParamRef) | |||
1369 | Param = ParamRef->getPointeeType(); | |||
1370 | ||||
1371 | // - If A is a reference type, A is replaced by the type referred to. | |||
1372 | const ReferenceType *ArgRef = Arg->getAs<ReferenceType>(); | |||
1373 | if (ArgRef) | |||
1374 | Arg = ArgRef->getPointeeType(); | |||
1375 | ||||
1376 | if (ParamRef && ArgRef && S.Context.hasSameUnqualifiedType(Param, Arg)) { | |||
1377 | // C++11 [temp.deduct.partial]p9: | |||
1378 | // If, for a given type, deduction succeeds in both directions (i.e., | |||
1379 | // the types are identical after the transformations above) and both | |||
1380 | // P and A were reference types [...]: | |||
1381 | // - if [one type] was an lvalue reference and [the other type] was | |||
1382 | // not, [the other type] is not considered to be at least as | |||
1383 | // specialized as [the first type] | |||
1384 | // - if [one type] is more cv-qualified than [the other type], | |||
1385 | // [the other type] is not considered to be at least as specialized | |||
1386 | // as [the first type] | |||
1387 | // Objective-C ARC adds: | |||
1388 | // - [one type] has non-trivial lifetime, [the other type] has | |||
1389 | // __unsafe_unretained lifetime, and the types are otherwise | |||
1390 | // identical | |||
1391 | // | |||
1392 | // A is "considered to be at least as specialized" as P iff deduction | |||
1393 | // succeeds, so we model this as a deduction failure. Note that | |||
1394 | // [the first type] is P and [the other type] is A here; the standard | |||
1395 | // gets this backwards. | |||
1396 | Qualifiers ParamQuals = Param.getQualifiers(); | |||
1397 | Qualifiers ArgQuals = Arg.getQualifiers(); | |||
1398 | if ((ParamRef->isLValueReferenceType() && | |||
1399 | !ArgRef->isLValueReferenceType()) || | |||
1400 | ParamQuals.isStrictSupersetOf(ArgQuals) || | |||
1401 | (ParamQuals.hasNonTrivialObjCLifetime() && | |||
1402 | ArgQuals.getObjCLifetime() == Qualifiers::OCL_ExplicitNone && | |||
1403 | ParamQuals.withoutObjCLifetime() == | |||
1404 | ArgQuals.withoutObjCLifetime())) { | |||
1405 | Info.FirstArg = TemplateArgument(ParamIn); | |||
1406 | Info.SecondArg = TemplateArgument(ArgIn); | |||
1407 | return Sema::TDK_NonDeducedMismatch; | |||
1408 | } | |||
1409 | } | |||
1410 | ||||
1411 | // C++11 [temp.deduct.partial]p7: | |||
1412 | // Remove any top-level cv-qualifiers: | |||
1413 | // - If P is a cv-qualified type, P is replaced by the cv-unqualified | |||
1414 | // version of P. | |||
1415 | Param = Param.getUnqualifiedType(); | |||
1416 | // - If A is a cv-qualified type, A is replaced by the cv-unqualified | |||
1417 | // version of A. | |||
1418 | Arg = Arg.getUnqualifiedType(); | |||
1419 | } else { | |||
1420 | // C++0x [temp.deduct.call]p4 bullet 1: | |||
1421 | // - If the original P is a reference type, the deduced A (i.e., the type | |||
1422 | // referred to by the reference) can be more cv-qualified than the | |||
1423 | // transformed A. | |||
1424 | if (TDF & TDF_ParamWithReferenceType) { | |||
1425 | Qualifiers Quals; | |||
1426 | QualType UnqualParam = S.Context.getUnqualifiedArrayType(Param, Quals); | |||
1427 | Quals.setCVRQualifiers(Quals.getCVRQualifiers() & | |||
1428 | Arg.getCVRQualifiers()); | |||
1429 | Param = S.Context.getQualifiedType(UnqualParam, Quals); | |||
1430 | } | |||
1431 | ||||
1432 | if ((TDF & TDF_TopLevelParameterTypeList) && !Param->isFunctionType()) { | |||
1433 | // C++0x [temp.deduct.type]p10: | |||
1434 | // If P and A are function types that originated from deduction when | |||
1435 | // taking the address of a function template (14.8.2.2) or when deducing | |||
1436 | // template arguments from a function declaration (14.8.2.6) and Pi and | |||
1437 | // Ai are parameters of the top-level parameter-type-list of P and A, | |||
1438 | // respectively, Pi is adjusted if it is a forwarding reference and Ai | |||
1439 | // is an lvalue reference, in | |||
1440 | // which case the type of Pi is changed to be the template parameter | |||
1441 | // type (i.e., T&& is changed to simply T). [ Note: As a result, when | |||
1442 | // Pi is T&& and Ai is X&, the adjusted Pi will be T, causing T to be | |||
1443 | // deduced as X&. - end note ] | |||
1444 | TDF &= ~TDF_TopLevelParameterTypeList; | |||
1445 | if (isForwardingReference(Param, 0) && Arg->isLValueReferenceType()) | |||
1446 | Param = Param->getPointeeType(); | |||
1447 | } | |||
1448 | } | |||
1449 | ||||
1450 | // C++ [temp.deduct.type]p9: | |||
1451 | // A template type argument T, a template template argument TT or a | |||
1452 | // template non-type argument i can be deduced if P and A have one of | |||
1453 | // the following forms: | |||
1454 | // | |||
1455 | // T | |||
1456 | // cv-list T | |||
1457 | if (const TemplateTypeParmType *TemplateTypeParm | |||
1458 | = Param->getAs<TemplateTypeParmType>()) { | |||
1459 | // Just skip any attempts to deduce from a placeholder type or a parameter | |||
1460 | // at a different depth. | |||
1461 | if (Arg->isPlaceholderType() || | |||
1462 | Info.getDeducedDepth() != TemplateTypeParm->getDepth()) | |||
1463 | return Sema::TDK_Success; | |||
1464 | ||||
1465 | unsigned Index = TemplateTypeParm->getIndex(); | |||
1466 | bool RecanonicalizeArg = false; | |||
1467 | ||||
1468 | // If the argument type is an array type, move the qualifiers up to the | |||
1469 | // top level, so they can be matched with the qualifiers on the parameter. | |||
1470 | if (isa<ArrayType>(Arg)) { | |||
1471 | Qualifiers Quals; | |||
1472 | Arg = S.Context.getUnqualifiedArrayType(Arg, Quals); | |||
1473 | if (Quals) { | |||
1474 | Arg = S.Context.getQualifiedType(Arg, Quals); | |||
1475 | RecanonicalizeArg = true; | |||
1476 | } | |||
1477 | } | |||
1478 | ||||
1479 | // The argument type can not be less qualified than the parameter | |||
1480 | // type. | |||
1481 | if (!(TDF & TDF_IgnoreQualifiers) && | |||
1482 | hasInconsistentOrSupersetQualifiersOf(Param, Arg)) { | |||
1483 | Info.Param = cast<TemplateTypeParmDecl>(TemplateParams->getParam(Index)); | |||
1484 | Info.FirstArg = TemplateArgument(Param); | |||
1485 | Info.SecondArg = TemplateArgument(Arg); | |||
1486 | return Sema::TDK_Underqualified; | |||
1487 | } | |||
1488 | ||||
1489 | // Do not match a function type with a cv-qualified type. | |||
1490 | // http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#1584 | |||
1491 | if (Arg->isFunctionType() && Param.hasQualifiers()) { | |||
1492 | return Sema::TDK_NonDeducedMismatch; | |||
1493 | } | |||
1494 | ||||
1495 | 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-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 1496, __PRETTY_FUNCTION__)) | |||
1496 | "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-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 1496, __PRETTY_FUNCTION__)); | |||
1497 | 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-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 1497, __PRETTY_FUNCTION__)); | |||
1498 | QualType DeducedType = Arg; | |||
1499 | ||||
1500 | // Remove any qualifiers on the parameter from the deduced type. | |||
1501 | // We checked the qualifiers for consistency above. | |||
1502 | Qualifiers DeducedQs = DeducedType.getQualifiers(); | |||
1503 | Qualifiers ParamQs = Param.getQualifiers(); | |||
1504 | DeducedQs.removeCVRQualifiers(ParamQs.getCVRQualifiers()); | |||
1505 | if (ParamQs.hasObjCGCAttr()) | |||
1506 | DeducedQs.removeObjCGCAttr(); | |||
1507 | if (ParamQs.hasAddressSpace()) | |||
1508 | DeducedQs.removeAddressSpace(); | |||
1509 | if (ParamQs.hasObjCLifetime()) | |||
1510 | DeducedQs.removeObjCLifetime(); | |||
1511 | ||||
1512 | // Objective-C ARC: | |||
1513 | // If template deduction would produce a lifetime qualifier on a type | |||
1514 | // that is not a lifetime type, template argument deduction fails. | |||
1515 | if (ParamQs.hasObjCLifetime() && !DeducedType->isObjCLifetimeType() && | |||
1516 | !DeducedType->isDependentType()) { | |||
1517 | Info.Param = cast<TemplateTypeParmDecl>(TemplateParams->getParam(Index)); | |||
1518 | Info.FirstArg = TemplateArgument(Param); | |||
1519 | Info.SecondArg = TemplateArgument(Arg); | |||
1520 | return Sema::TDK_Underqualified; | |||
1521 | } | |||
1522 | ||||
1523 | // Objective-C ARC: | |||
1524 | // If template deduction would produce an argument type with lifetime type | |||
1525 | // but no lifetime qualifier, the __strong lifetime qualifier is inferred. | |||
1526 | if (S.getLangOpts().ObjCAutoRefCount && | |||
1527 | DeducedType->isObjCLifetimeType() && | |||
1528 | !DeducedQs.hasObjCLifetime()) | |||
1529 | DeducedQs.setObjCLifetime(Qualifiers::OCL_Strong); | |||
1530 | ||||
1531 | DeducedType = S.Context.getQualifiedType(DeducedType.getUnqualifiedType(), | |||
1532 | DeducedQs); | |||
1533 | ||||
1534 | if (RecanonicalizeArg) | |||
1535 | DeducedType = S.Context.getCanonicalType(DeducedType); | |||
1536 | ||||
1537 | DeducedTemplateArgument NewDeduced(DeducedType, DeducedFromArrayBound); | |||
1538 | DeducedTemplateArgument Result = checkDeducedTemplateArguments(S.Context, | |||
1539 | Deduced[Index], | |||
1540 | NewDeduced); | |||
1541 | if (Result.isNull()) { | |||
1542 | Info.Param = cast<TemplateTypeParmDecl>(TemplateParams->getParam(Index)); | |||
1543 | Info.FirstArg = Deduced[Index]; | |||
1544 | Info.SecondArg = NewDeduced; | |||
1545 | return Sema::TDK_Inconsistent; | |||
1546 | } | |||
1547 | ||||
1548 | Deduced[Index] = Result; | |||
1549 | return Sema::TDK_Success; | |||
1550 | } | |||
1551 | ||||
1552 | // Set up the template argument deduction information for a failure. | |||
1553 | Info.FirstArg = TemplateArgument(ParamIn); | |||
1554 | Info.SecondArg = TemplateArgument(ArgIn); | |||
1555 | ||||
1556 | // If the parameter is an already-substituted template parameter | |||
1557 | // pack, do nothing: we don't know which of its arguments to look | |||
1558 | // at, so we have to wait until all of the parameter packs in this | |||
1559 | // expansion have arguments. | |||
1560 | if (isa<SubstTemplateTypeParmPackType>(Param)) | |||
1561 | return Sema::TDK_Success; | |||
1562 | ||||
1563 | // Check the cv-qualifiers on the parameter and argument types. | |||
1564 | CanQualType CanParam = S.Context.getCanonicalType(Param); | |||
1565 | CanQualType CanArg = S.Context.getCanonicalType(Arg); | |||
1566 | if (!(TDF & TDF_IgnoreQualifiers)) { | |||
1567 | if (TDF & TDF_ParamWithReferenceType) { | |||
1568 | if (hasInconsistentOrSupersetQualifiersOf(Param, Arg)) | |||
1569 | return Sema::TDK_NonDeducedMismatch; | |||
1570 | } else if (TDF & TDF_ArgWithReferenceType) { | |||
1571 | // C++ [temp.deduct.conv]p4: | |||
1572 | // If the original A is a reference type, A can be more cv-qualified | |||
1573 | // than the deduced A | |||
1574 | if (!Arg.getQualifiers().compatiblyIncludes(Param.getQualifiers())) | |||
1575 | return Sema::TDK_NonDeducedMismatch; | |||
1576 | ||||
1577 | // Strip out all extra qualifiers from the argument to figure out the | |||
1578 | // type we're converting to, prior to the qualification conversion. | |||
1579 | Qualifiers Quals; | |||
1580 | Arg = S.Context.getUnqualifiedArrayType(Arg, Quals); | |||
1581 | Arg = S.Context.getQualifiedType(Arg, Param.getQualifiers()); | |||
1582 | } else if (!IsPossiblyOpaquelyQualifiedType(Param)) { | |||
1583 | if (Param.getCVRQualifiers() != Arg.getCVRQualifiers()) | |||
1584 | return Sema::TDK_NonDeducedMismatch; | |||
1585 | } | |||
1586 | ||||
1587 | // If the parameter type is not dependent, there is nothing to deduce. | |||
1588 | if (!Param->isDependentType()) { | |||
1589 | if (!(TDF & TDF_SkipNonDependent)) { | |||
1590 | bool NonDeduced = | |||
1591 | (TDF & TDF_AllowCompatibleFunctionType) | |||
1592 | ? !S.isSameOrCompatibleFunctionType(CanParam, CanArg) | |||
1593 | : Param != Arg; | |||
1594 | if (NonDeduced) { | |||
1595 | return Sema::TDK_NonDeducedMismatch; | |||
1596 | } | |||
1597 | } | |||
1598 | return Sema::TDK_Success; | |||
1599 | } | |||
1600 | } else if (!Param->isDependentType()) { | |||
1601 | if (!(TDF & TDF_SkipNonDependent)) { | |||
1602 | CanQualType ParamUnqualType = CanParam.getUnqualifiedType(), | |||
1603 | ArgUnqualType = CanArg.getUnqualifiedType(); | |||
1604 | bool Success = | |||
1605 | (TDF & TDF_AllowCompatibleFunctionType) | |||
1606 | ? S.isSameOrCompatibleFunctionType(ParamUnqualType, ArgUnqualType) | |||
1607 | : ParamUnqualType == ArgUnqualType; | |||
1608 | if (Success) | |||
1609 | return Sema::TDK_Success; | |||
1610 | } else { | |||
1611 | return Sema::TDK_Success; | |||
1612 | } | |||
1613 | } | |||
1614 | ||||
1615 | switch (Param->getTypeClass()) { | |||
1616 | // Non-canonical types cannot appear here. | |||
1617 | #define NON_CANONICAL_TYPE(Class, Base) \ | |||
1618 | case Type::Class: llvm_unreachable("deducing non-canonical type: " #Class)::llvm::llvm_unreachable_internal("deducing non-canonical type: " #Class, "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 1618); | |||
1619 | #define TYPE(Class, Base) | |||
1620 | #include "clang/AST/TypeNodes.inc" | |||
1621 | ||||
1622 | case Type::TemplateTypeParm: | |||
1623 | case Type::SubstTemplateTypeParmPack: | |||
1624 | llvm_unreachable("Type nodes handled above")::llvm::llvm_unreachable_internal("Type nodes handled above", "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 1624); | |||
1625 | ||||
1626 | // These types cannot be dependent, so simply check whether the types are | |||
1627 | // the same. | |||
1628 | case Type::Builtin: | |||
1629 | case Type::VariableArray: | |||
1630 | case Type::Vector: | |||
1631 | case Type::FunctionNoProto: | |||
1632 | case Type::Record: | |||
1633 | case Type::Enum: | |||
1634 | case Type::ObjCObject: | |||
1635 | case Type::ObjCInterface: | |||
1636 | case Type::ObjCObjectPointer: | |||
1637 | case Type::ExtInt: | |||
1638 | if (TDF & TDF_SkipNonDependent) | |||
1639 | return Sema::TDK_Success; | |||
1640 | ||||
1641 | if (TDF & TDF_IgnoreQualifiers) { | |||
1642 | Param = Param.getUnqualifiedType(); | |||
1643 | Arg = Arg.getUnqualifiedType(); | |||
1644 | } | |||
1645 | ||||
1646 | return Param == Arg? Sema::TDK_Success : Sema::TDK_NonDeducedMismatch; | |||
1647 | ||||
1648 | // _Complex T [placeholder extension] | |||
1649 | case Type::Complex: | |||
1650 | if (const ComplexType *ComplexArg = Arg->getAs<ComplexType>()) | |||
1651 | return DeduceTemplateArgumentsByTypeMatch(S, TemplateParams, | |||
1652 | cast<ComplexType>(Param)->getElementType(), | |||
1653 | ComplexArg->getElementType(), | |||
1654 | Info, Deduced, TDF); | |||
1655 | ||||
1656 | return Sema::TDK_NonDeducedMismatch; | |||
1657 | ||||
1658 | // _Atomic T [extension] | |||
1659 | case Type::Atomic: | |||
1660 | if (const AtomicType *AtomicArg = Arg->getAs<AtomicType>()) | |||
1661 | return DeduceTemplateArgumentsByTypeMatch(S, TemplateParams, | |||
1662 | cast<AtomicType>(Param)->getValueType(), | |||
1663 | AtomicArg->getValueType(), | |||
1664 | Info, Deduced, TDF); | |||
1665 | ||||
1666 | return Sema::TDK_NonDeducedMismatch; | |||
1667 | ||||
1668 | // T * | |||
1669 | case Type::Pointer: { | |||
1670 | QualType PointeeType; | |||
1671 | if (const PointerType *PointerArg = Arg->getAs<PointerType>()) { | |||
1672 | PointeeType = PointerArg->getPointeeType(); | |||
1673 | } else if (const ObjCObjectPointerType *PointerArg | |||
1674 | = Arg->getAs<ObjCObjectPointerType>()) { | |||
1675 | PointeeType = PointerArg->getPointeeType(); | |||
1676 | } else { | |||
1677 | return Sema::TDK_NonDeducedMismatch; | |||
1678 | } | |||
1679 | ||||
1680 | unsigned SubTDF = TDF & (TDF_IgnoreQualifiers | TDF_DerivedClass); | |||
1681 | return DeduceTemplateArgumentsByTypeMatch(S, TemplateParams, | |||
1682 | cast<PointerType>(Param)->getPointeeType(), | |||
1683 | PointeeType, | |||
1684 | Info, Deduced, SubTDF); | |||
1685 | } | |||
1686 | ||||
1687 | // T & | |||
1688 | case Type::LValueReference: { | |||
1689 | const LValueReferenceType *ReferenceArg = | |||
1690 | Arg->getAs<LValueReferenceType>(); | |||
1691 | if (!ReferenceArg) | |||
1692 | return Sema::TDK_NonDeducedMismatch; | |||
1693 | ||||
1694 | return DeduceTemplateArgumentsByTypeMatch(S, TemplateParams, | |||
1695 | cast<LValueReferenceType>(Param)->getPointeeType(), | |||
1696 | ReferenceArg->getPointeeType(), Info, Deduced, 0); | |||
1697 | } | |||
1698 | ||||
1699 | // T && [C++0x] | |||
1700 | case Type::RValueReference: { | |||
1701 | const RValueReferenceType *ReferenceArg = | |||
1702 | Arg->getAs<RValueReferenceType>(); | |||
1703 | if (!ReferenceArg) | |||
1704 | return Sema::TDK_NonDeducedMismatch; | |||
1705 | ||||
1706 | return DeduceTemplateArgumentsByTypeMatch(S, TemplateParams, | |||
1707 | cast<RValueReferenceType>(Param)->getPointeeType(), | |||
1708 | ReferenceArg->getPointeeType(), | |||
1709 | Info, Deduced, 0); | |||
1710 | } | |||
1711 | ||||
1712 | // T [] (implied, but not stated explicitly) | |||
1713 | case Type::IncompleteArray: { | |||
1714 | const IncompleteArrayType *IncompleteArrayArg = | |||
1715 | S.Context.getAsIncompleteArrayType(Arg); | |||
1716 | if (!IncompleteArrayArg) | |||
1717 | return Sema::TDK_NonDeducedMismatch; | |||
1718 | ||||
1719 | unsigned SubTDF = TDF & TDF_IgnoreQualifiers; | |||
1720 | return DeduceTemplateArgumentsByTypeMatch(S, TemplateParams, | |||
1721 | S.Context.getAsIncompleteArrayType(Param)->getElementType(), | |||
1722 | IncompleteArrayArg->getElementType(), | |||
1723 | Info, Deduced, SubTDF); | |||
1724 | } | |||
1725 | ||||
1726 | // T [integer-constant] | |||
1727 | case Type::ConstantArray: { | |||
1728 | const ConstantArrayType *ConstantArrayArg = | |||
1729 | S.Context.getAsConstantArrayType(Arg); | |||
1730 | if (!ConstantArrayArg) | |||
1731 | return Sema::TDK_NonDeducedMismatch; | |||
1732 | ||||
1733 | const ConstantArrayType *ConstantArrayParm = | |||
1734 | S.Context.getAsConstantArrayType(Param); | |||
1735 | if (ConstantArrayArg->getSize() != ConstantArrayParm->getSize()) | |||
1736 | return Sema::TDK_NonDeducedMismatch; | |||
1737 | ||||
1738 | unsigned SubTDF = TDF & TDF_IgnoreQualifiers; | |||
1739 | return DeduceTemplateArgumentsByTypeMatch(S, TemplateParams, | |||
1740 | ConstantArrayParm->getElementType(), | |||
1741 | ConstantArrayArg->getElementType(), | |||
1742 | Info, Deduced, SubTDF); | |||
1743 | } | |||
1744 | ||||
1745 | // type [i] | |||
1746 | case Type::DependentSizedArray: { | |||
1747 | const ArrayType *ArrayArg = S.Context.getAsArrayType(Arg); | |||
1748 | if (!ArrayArg) | |||
1749 | return Sema::TDK_NonDeducedMismatch; | |||
1750 | ||||
1751 | unsigned SubTDF = TDF & TDF_IgnoreQualifiers; | |||
1752 | ||||
1753 | // Check the element type of the arrays | |||
1754 | const DependentSizedArrayType *DependentArrayParm | |||
1755 | = S.Context.getAsDependentSizedArrayType(Param); | |||
1756 | if (Sema::TemplateDeductionResult Result | |||
1757 | = DeduceTemplateArgumentsByTypeMatch(S, TemplateParams, | |||
1758 | DependentArrayParm->getElementType(), | |||
1759 | ArrayArg->getElementType(), | |||
1760 | Info, Deduced, SubTDF)) | |||
1761 | return Result; | |||
1762 | ||||
1763 | // Determine the array bound is something we can deduce. | |||
1764 | const NonTypeTemplateParmDecl *NTTP | |||
1765 | = getDeducedParameterFromExpr(Info, DependentArrayParm->getSizeExpr()); | |||
1766 | if (!NTTP) | |||
1767 | return Sema::TDK_Success; | |||
1768 | ||||
1769 | // We can perform template argument deduction for the given non-type | |||
1770 | // template parameter. | |||
1771 | 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-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 1772, __PRETTY_FUNCTION__)) | |||
1772 | "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-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 1772, __PRETTY_FUNCTION__)); | |||
1773 | if (const ConstantArrayType *ConstantArrayArg | |||
1774 | = dyn_cast<ConstantArrayType>(ArrayArg)) { | |||
1775 | llvm::APSInt Size(ConstantArrayArg->getSize()); | |||
1776 | return DeduceNonTypeTemplateArgument(S, TemplateParams, NTTP, Size, | |||
1777 | S.Context.getSizeType(), | |||
1778 | /*ArrayBound=*/true, | |||
1779 | Info, Deduced); | |||
1780 | } | |||
1781 | if (const DependentSizedArrayType *DependentArrayArg | |||
1782 | = dyn_cast<DependentSizedArrayType>(ArrayArg)) | |||
1783 | if (DependentArrayArg->getSizeExpr()) | |||
1784 | return DeduceNonTypeTemplateArgument(S, TemplateParams, NTTP, | |||
1785 | DependentArrayArg->getSizeExpr(), | |||
1786 | Info, Deduced); | |||
1787 | ||||
1788 | // Incomplete type does not match a dependently-sized array type | |||
1789 | return Sema::TDK_NonDeducedMismatch; | |||
1790 | } | |||
1791 | ||||
1792 | // type(*)(T) | |||
1793 | // T(*)() | |||
1794 | // T(*)(T) | |||
1795 | case Type::FunctionProto: { | |||
1796 | unsigned SubTDF = TDF & TDF_TopLevelParameterTypeList; | |||
1797 | const FunctionProtoType *FunctionProtoArg = | |||
1798 | dyn_cast<FunctionProtoType>(Arg); | |||
1799 | if (!FunctionProtoArg) | |||
1800 | return Sema::TDK_NonDeducedMismatch; | |||
1801 | ||||
1802 | const FunctionProtoType *FunctionProtoParam = | |||
1803 | cast<FunctionProtoType>(Param); | |||
1804 | ||||
1805 | if (FunctionProtoParam->getMethodQuals() | |||
1806 | != FunctionProtoArg->getMethodQuals() || | |||
1807 | FunctionProtoParam->getRefQualifier() | |||
1808 | != FunctionProtoArg->getRefQualifier() || | |||
1809 | FunctionProtoParam->isVariadic() != FunctionProtoArg->isVariadic()) | |||
1810 | return Sema::TDK_NonDeducedMismatch; | |||
1811 | ||||
1812 | // Check return types. | |||
1813 | if (auto Result = DeduceTemplateArgumentsByTypeMatch( | |||
1814 | S, TemplateParams, FunctionProtoParam->getReturnType(), | |||
1815 | FunctionProtoArg->getReturnType(), Info, Deduced, 0)) | |||
1816 | return Result; | |||
1817 | ||||
1818 | // Check parameter types. | |||
1819 | if (auto Result = DeduceTemplateArguments( | |||
1820 | S, TemplateParams, FunctionProtoParam->param_type_begin(), | |||
1821 | FunctionProtoParam->getNumParams(), | |||
1822 | FunctionProtoArg->param_type_begin(), | |||
1823 | FunctionProtoArg->getNumParams(), Info, Deduced, SubTDF)) | |||
1824 | return Result; | |||
1825 | ||||
1826 | if (TDF & TDF_AllowCompatibleFunctionType) | |||
1827 | return Sema::TDK_Success; | |||
1828 | ||||
1829 | // FIXME: Per core-2016/10/1019 (no corresponding core issue yet), permit | |||
1830 | // deducing through the noexcept-specifier if it's part of the canonical | |||
1831 | // type. libstdc++ relies on this. | |||
1832 | Expr *NoexceptExpr = FunctionProtoParam->getNoexceptExpr(); | |||
1833 | if (const NonTypeTemplateParmDecl *NTTP = | |||
1834 | NoexceptExpr ? getDeducedParameterFromExpr(Info, NoexceptExpr) | |||
1835 | : nullptr) { | |||
1836 | 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-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 1837, __PRETTY_FUNCTION__)) | |||
1837 | "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-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 1837, __PRETTY_FUNCTION__)); | |||
1838 | ||||
1839 | llvm::APSInt Noexcept(1); | |||
1840 | switch (FunctionProtoArg->canThrow()) { | |||
1841 | case CT_Cannot: | |||
1842 | Noexcept = 1; | |||
1843 | LLVM_FALLTHROUGH[[gnu::fallthrough]]; | |||
1844 | ||||
1845 | case CT_Can: | |||
1846 | // We give E in noexcept(E) the "deduced from array bound" treatment. | |||
1847 | // FIXME: Should we? | |||
1848 | return DeduceNonTypeTemplateArgument( | |||
1849 | S, TemplateParams, NTTP, Noexcept, S.Context.BoolTy, | |||
1850 | /*ArrayBound*/true, Info, Deduced); | |||
1851 | ||||
1852 | case CT_Dependent: | |||
1853 | if (Expr *ArgNoexceptExpr = FunctionProtoArg->getNoexceptExpr()) | |||
1854 | return DeduceNonTypeTemplateArgument( | |||
1855 | S, TemplateParams, NTTP, ArgNoexceptExpr, Info, Deduced); | |||
1856 | // Can't deduce anything from throw(T...). | |||
1857 | break; | |||
1858 | } | |||
1859 | } | |||
1860 | // FIXME: Detect non-deduced exception specification mismatches? | |||
1861 | // | |||
1862 | // Careful about [temp.deduct.call] and [temp.deduct.conv], which allow | |||
1863 | // top-level differences in noexcept-specifications. | |||
1864 | ||||
1865 | return Sema::TDK_Success; | |||
1866 | } | |||
1867 | ||||
1868 | case Type::InjectedClassName: | |||
1869 | // Treat a template's injected-class-name as if the template | |||
1870 | // specialization type had been used. | |||
1871 | Param = cast<InjectedClassNameType>(Param) | |||
1872 | ->getInjectedSpecializationType(); | |||
1873 | 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-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 1874, __PRETTY_FUNCTION__)) | |||
1874 | "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-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 1874, __PRETTY_FUNCTION__)); | |||
1875 | LLVM_FALLTHROUGH[[gnu::fallthrough]]; | |||
1876 | ||||
1877 | // template-name<T> (where template-name refers to a class template) | |||
1878 | // template-name<i> | |||
1879 | // TT<T> | |||
1880 | // TT<i> | |||
1881 | // TT<> | |||
1882 | case Type::TemplateSpecialization: { | |||
1883 | const TemplateSpecializationType *SpecParam = | |||
1884 | cast<TemplateSpecializationType>(Param); | |||
1885 | ||||
1886 | // When Arg cannot be a derived class, we can just try to deduce template | |||
1887 | // arguments from the template-id. | |||
1888 | const RecordType *RecordT = Arg->getAs<RecordType>(); | |||
1889 | if (!(TDF & TDF_DerivedClass) || !RecordT) | |||
1890 | return DeduceTemplateArguments(S, TemplateParams, SpecParam, Arg, Info, | |||
1891 | Deduced); | |||
1892 | ||||
1893 | SmallVector<DeducedTemplateArgument, 8> DeducedOrig(Deduced.begin(), | |||
1894 | Deduced.end()); | |||
1895 | ||||
1896 | Sema::TemplateDeductionResult Result = DeduceTemplateArguments( | |||
1897 | S, TemplateParams, SpecParam, Arg, Info, Deduced); | |||
1898 | ||||
1899 | if (Result == Sema::TDK_Success) | |||
1900 | return Result; | |||
1901 | ||||
1902 | // We cannot inspect base classes as part of deduction when the type | |||
1903 | // is incomplete, so either instantiate any templates necessary to | |||
1904 | // complete the type, or skip over it if it cannot be completed. | |||
1905 | if (!S.isCompleteType(Info.getLocation(), Arg)) | |||
1906 | return Result; | |||
1907 | ||||
1908 | // Reset the incorrectly deduced argument from above. | |||
1909 | Deduced = DeducedOrig; | |||
1910 | ||||
1911 | // Check bases according to C++14 [temp.deduct.call] p4b3: | |||
1912 | Sema::TemplateDeductionResult BaseResult = DeduceTemplateBases( | |||
1913 | S, RecordT, TemplateParams, SpecParam, Info, Deduced); | |||
1914 | ||||
1915 | if (BaseResult != Sema::TDK_Invalid) | |||
1916 | return BaseResult; | |||
1917 | return Result; | |||
1918 | } | |||
1919 | ||||
1920 | // T type::* | |||
1921 | // T T::* | |||
1922 | // T (type::*)() | |||
1923 | // type (T::*)() | |||
1924 | // type (type::*)(T) | |||
1925 | // type (T::*)(T) | |||
1926 | // T (type::*)(T) | |||
1927 | // T (T::*)() | |||
1928 | // T (T::*)(T) | |||
1929 | case Type::MemberPointer: { | |||
1930 | const MemberPointerType *MemPtrParam = cast<MemberPointerType>(Param); | |||
1931 | const MemberPointerType *MemPtrArg = dyn_cast<MemberPointerType>(Arg); | |||
1932 | if (!MemPtrArg) | |||
1933 | return Sema::TDK_NonDeducedMismatch; | |||
1934 | ||||
1935 | QualType ParamPointeeType = MemPtrParam->getPointeeType(); | |||
1936 | if (ParamPointeeType->isFunctionType()) | |||
1937 | S.adjustMemberFunctionCC(ParamPointeeType, /*IsStatic=*/true, | |||
1938 | /*IsCtorOrDtor=*/false, Info.getLocation()); | |||
1939 | QualType ArgPointeeType = MemPtrArg->getPointeeType(); | |||
1940 | if (ArgPointeeType->isFunctionType()) | |||
1941 | S.adjustMemberFunctionCC(ArgPointeeType, /*IsStatic=*/true, | |||
1942 | /*IsCtorOrDtor=*/false, Info.getLocation()); | |||
1943 | ||||
1944 | if (Sema::TemplateDeductionResult Result | |||
1945 | = DeduceTemplateArgumentsByTypeMatch(S, TemplateParams, | |||
1946 | ParamPointeeType, | |||
1947 | ArgPointeeType, | |||
1948 | Info, Deduced, | |||
1949 | TDF & TDF_IgnoreQualifiers)) | |||
1950 | return Result; | |||
1951 | ||||
1952 | return DeduceTemplateArgumentsByTypeMatch(S, TemplateParams, | |||
1953 | QualType(MemPtrParam->getClass(), 0), | |||
1954 | QualType(MemPtrArg->getClass(), 0), | |||
1955 | Info, Deduced, | |||
1956 | TDF & TDF_IgnoreQualifiers); | |||
1957 | } | |||
1958 | ||||
1959 | // (clang extension) | |||
1960 | // | |||
1961 | // type(^)(T) | |||
1962 | // T(^)() | |||
1963 | // T(^)(T) | |||
1964 | case Type::BlockPointer: { | |||
1965 | const BlockPointerType *BlockPtrParam = cast<BlockPointerType>(Param); | |||
1966 | const BlockPointerType *BlockPtrArg = dyn_cast<BlockPointerType>(Arg); | |||
1967 | ||||
1968 | if (!BlockPtrArg) | |||
1969 | return Sema::TDK_NonDeducedMismatch; | |||
1970 | ||||
1971 | return DeduceTemplateArgumentsByTypeMatch(S, TemplateParams, | |||
1972 | BlockPtrParam->getPointeeType(), | |||
1973 | BlockPtrArg->getPointeeType(), | |||
1974 | Info, Deduced, 0); | |||
1975 | } | |||
1976 | ||||
1977 | // (clang extension) | |||
1978 | // | |||
1979 | // T __attribute__(((ext_vector_type(<integral constant>)))) | |||
1980 | case Type::ExtVector: { | |||
1981 | const ExtVectorType *VectorParam = cast<ExtVectorType>(Param); | |||
1982 | if (const ExtVectorType *VectorArg = dyn_cast<ExtVectorType>(Arg)) { | |||
1983 | // Make sure that the vectors have the same number of elements. | |||
1984 | if (VectorParam->getNumElements() != VectorArg->getNumElements()) | |||
1985 | return Sema::TDK_NonDeducedMismatch; | |||
1986 | ||||
1987 | // Perform deduction on the element types. | |||
1988 | return DeduceTemplateArgumentsByTypeMatch(S, TemplateParams, | |||
1989 | VectorParam->getElementType(), | |||
1990 | VectorArg->getElementType(), | |||
1991 | Info, Deduced, TDF); | |||
1992 | } | |||
1993 | ||||
1994 | if (const DependentSizedExtVectorType *VectorArg | |||
1995 | = dyn_cast<DependentSizedExtVectorType>(Arg)) { | |||
1996 | // We can't check the number of elements, since the argument has a | |||
1997 | // dependent number of elements. This can only occur during partial | |||
1998 | // ordering. | |||
1999 | ||||
2000 | // Perform deduction on the element types. | |||
2001 | return DeduceTemplateArgumentsByTypeMatch(S, TemplateParams, | |||
2002 | VectorParam->getElementType(), | |||
2003 | VectorArg->getElementType(), | |||
2004 | Info, Deduced, TDF); | |||
2005 | } | |||
2006 | ||||
2007 | return Sema::TDK_NonDeducedMismatch; | |||
2008 | } | |||
2009 | ||||
2010 | case Type::DependentVector: { | |||
2011 | const auto *VectorParam = cast<DependentVectorType>(Param); | |||
2012 | ||||
2013 | if (const auto *VectorArg = dyn_cast<VectorType>(Arg)) { | |||
2014 | // Perform deduction on the element types. | |||
2015 | if (Sema::TemplateDeductionResult Result = | |||
2016 | DeduceTemplateArgumentsByTypeMatch( | |||
2017 | S, TemplateParams, VectorParam->getElementType(), | |||
2018 | VectorArg->getElementType(), Info, Deduced, TDF)) | |||
2019 | return Result; | |||
2020 | ||||
2021 | // Perform deduction on the vector size, if we can. | |||
2022 | const NonTypeTemplateParmDecl *NTTP = | |||
2023 | getDeducedParameterFromExpr(Info, VectorParam->getSizeExpr()); | |||
2024 | if (!NTTP) | |||
2025 | return Sema::TDK_Success; | |||
2026 | ||||
2027 | llvm::APSInt ArgSize(S.Context.getTypeSize(S.Context.IntTy), false); | |||
2028 | ArgSize = VectorArg->getNumElements(); | |||
2029 | // Note that we use the "array bound" rules here; just like in that | |||
2030 | // case, we don't have any particular type for the vector size, but | |||
2031 | // we can provide one if necessary. | |||
2032 | return DeduceNonTypeTemplateArgument(S, TemplateParams, NTTP, ArgSize, | |||
2033 | S.Context.UnsignedIntTy, true, | |||
2034 | Info, Deduced); | |||
2035 | } | |||
2036 | ||||
2037 | if (const auto *VectorArg = dyn_cast<DependentVectorType>(Arg)) { | |||
2038 | // Perform deduction on the element types. | |||
2039 | if (Sema::TemplateDeductionResult Result = | |||
2040 | DeduceTemplateArgumentsByTypeMatch( | |||
2041 | S, TemplateParams, VectorParam->getElementType(), | |||
2042 | VectorArg->getElementType(), Info, Deduced, TDF)) | |||
2043 | return Result; | |||
2044 | ||||
2045 | // Perform deduction on the vector size, if we can. | |||
2046 | const NonTypeTemplateParmDecl *NTTP = getDeducedParameterFromExpr( | |||
2047 | Info, VectorParam->getSizeExpr()); | |||
2048 | if (!NTTP) | |||
2049 | return Sema::TDK_Success; | |||
2050 | ||||
2051 | return DeduceNonTypeTemplateArgument( | |||
2052 | S, TemplateParams, NTTP, VectorArg->getSizeExpr(), Info, Deduced); | |||
2053 | } | |||
2054 | ||||
2055 | return Sema::TDK_NonDeducedMismatch; | |||
2056 | } | |||
2057 | ||||
2058 | // (clang extension) | |||
2059 | // | |||
2060 | // T __attribute__(((ext_vector_type(N)))) | |||
2061 | case Type::DependentSizedExtVector: { | |||
2062 | const DependentSizedExtVectorType *VectorParam | |||
2063 | = cast<DependentSizedExtVectorType>(Param); | |||
2064 | ||||
2065 | if (const ExtVectorType *VectorArg = dyn_cast<ExtVectorType>(Arg)) { | |||
2066 | // Perform deduction on the element types. | |||
2067 | if (Sema::TemplateDeductionResult Result | |||
2068 | = DeduceTemplateArgumentsByTypeMatch(S, TemplateParams, | |||
2069 | VectorParam->getElementType(), | |||
2070 | VectorArg->getElementType(), | |||
2071 | Info, Deduced, TDF)) | |||
2072 | return Result; | |||
2073 | ||||
2074 | // Perform deduction on the vector size, if we can. | |||
2075 | const NonTypeTemplateParmDecl *NTTP = | |||
2076 | getDeducedParameterFromExpr(Info, VectorParam->getSizeExpr()); | |||
2077 | if (!NTTP) | |||
2078 | return Sema::TDK_Success; | |||
2079 | ||||
2080 | llvm::APSInt ArgSize(S.Context.getTypeSize(S.Context.IntTy), false); | |||
2081 | ArgSize = VectorArg->getNumElements(); | |||
2082 | // Note that we use the "array bound" rules here; just like in that | |||
2083 | // case, we don't have any particular type for the vector size, but | |||
2084 | // we can provide one if necessary. | |||
2085 | return DeduceNonTypeTemplateArgument(S, TemplateParams, NTTP, ArgSize, | |||
2086 | S.Context.IntTy, true, Info, | |||
2087 | Deduced); | |||
2088 | } | |||
2089 | ||||
2090 | if (const DependentSizedExtVectorType *VectorArg | |||
2091 | = dyn_cast<DependentSizedExtVectorType>(Arg)) { | |||
2092 | // Perform deduction on the element types. | |||
2093 | if (Sema::TemplateDeductionResult Result | |||
2094 | = DeduceTemplateArgumentsByTypeMatch(S, TemplateParams, | |||
2095 | VectorParam->getElementType(), | |||
2096 | VectorArg->getElementType(), | |||
2097 | Info, Deduced, TDF)) | |||
2098 | return Result; | |||
2099 | ||||
2100 | // Perform deduction on the vector size, if we can. | |||
2101 | const NonTypeTemplateParmDecl *NTTP = | |||
2102 | getDeducedParameterFromExpr(Info, VectorParam->getSizeExpr()); | |||
2103 | if (!NTTP) | |||
2104 | return Sema::TDK_Success; | |||
2105 | ||||
2106 | return DeduceNonTypeTemplateArgument(S, TemplateParams, NTTP, | |||
2107 | VectorArg->getSizeExpr(), | |||
2108 | Info, Deduced); | |||
2109 | } | |||
2110 | ||||
2111 | return Sema::TDK_NonDeducedMismatch; | |||
2112 | } | |||
2113 | ||||
2114 | // (clang extension) | |||
2115 | // | |||
2116 | // T __attribute__((matrix_type(<integral constant>, | |||
2117 | // <integral constant>))) | |||
2118 | case Type::ConstantMatrix: { | |||
2119 | const ConstantMatrixType *MatrixArg = dyn_cast<ConstantMatrixType>(Arg); | |||
2120 | if (!MatrixArg) | |||
2121 | return Sema::TDK_NonDeducedMismatch; | |||
2122 | ||||
2123 | const ConstantMatrixType *MatrixParam = cast<ConstantMatrixType>(Param); | |||
2124 | // Check that the dimensions are the same | |||
2125 | if (MatrixParam->getNumRows() != MatrixArg->getNumRows() || | |||
2126 | MatrixParam->getNumColumns() != MatrixArg->getNumColumns()) { | |||
2127 | return Sema::TDK_NonDeducedMismatch; | |||
2128 | } | |||
2129 | // Perform deduction on element types. | |||
2130 | return DeduceTemplateArgumentsByTypeMatch( | |||
2131 | S, TemplateParams, MatrixParam->getElementType(), | |||
2132 | MatrixArg->getElementType(), Info, Deduced, TDF); | |||
2133 | } | |||
2134 | ||||
2135 | case Type::DependentSizedMatrix: { | |||
2136 | const MatrixType *MatrixArg = dyn_cast<MatrixType>(Arg); | |||
2137 | if (!MatrixArg) | |||
2138 | return Sema::TDK_NonDeducedMismatch; | |||
2139 | ||||
2140 | // Check the element type of the matrixes. | |||
2141 | const DependentSizedMatrixType *MatrixParam = | |||
2142 | cast<DependentSizedMatrixType>(Param); | |||
2143 | if (Sema::TemplateDeductionResult Result = | |||
2144 | DeduceTemplateArgumentsByTypeMatch( | |||
2145 | S, TemplateParams, MatrixParam->getElementType(), | |||
2146 | MatrixArg->getElementType(), Info, Deduced, TDF)) | |||
2147 | return Result; | |||
2148 | ||||
2149 | // Try to deduce a matrix dimension. | |||
2150 | auto DeduceMatrixArg = | |||
2151 | [&S, &Info, &Deduced, &TemplateParams]( | |||
2152 | Expr *ParamExpr, const MatrixType *Arg, | |||
2153 | unsigned (ConstantMatrixType::*GetArgDimension)() const, | |||
2154 | Expr *(DependentSizedMatrixType::*GetArgDimensionExpr)() const) { | |||
2155 | const auto *ArgConstMatrix = dyn_cast<ConstantMatrixType>(Arg); | |||
| ||||
2156 | const auto *ArgDepMatrix = dyn_cast<DependentSizedMatrixType>(Arg); | |||
2157 | if (!ParamExpr->isValueDependent()) { | |||
2158 | Optional<llvm::APSInt> ParamConst = | |||
2159 | ParamExpr->getIntegerConstantExpr(S.Context); | |||
2160 | if (!ParamConst) | |||
2161 | return Sema::TDK_NonDeducedMismatch; | |||
2162 | ||||
2163 | if (ArgConstMatrix) { | |||
2164 | if ((ArgConstMatrix->*GetArgDimension)() == *ParamConst) | |||
2165 | return Sema::TDK_Success; | |||
2166 | return Sema::TDK_NonDeducedMismatch; | |||
2167 | } | |||
2168 | ||||
2169 | Expr *ArgExpr = (ArgDepMatrix->*GetArgDimensionExpr)(); | |||
2170 | if (!ArgExpr->isValueDependent()) | |||
2171 | if (Optional<llvm::APSInt> ArgConst = | |||
2172 | ArgExpr->getIntegerConstantExpr(S.Context)) | |||
2173 | if (*ArgConst == *ParamConst) | |||
2174 | return Sema::TDK_Success; | |||
2175 | return Sema::TDK_NonDeducedMismatch; | |||
2176 | } | |||
2177 | ||||
2178 | const NonTypeTemplateParmDecl *NTTP = | |||
2179 | getDeducedParameterFromExpr(Info, ParamExpr); | |||
2180 | if (!NTTP) | |||
2181 | return Sema::TDK_Success; | |||
2182 | ||||
2183 | if (ArgConstMatrix
| |||
2184 | llvm::APSInt ArgConst( | |||
2185 | S.Context.getTypeSize(S.Context.getSizeType())); | |||
2186 | ArgConst = (ArgConstMatrix->*GetArgDimension)(); | |||
2187 | return DeduceNonTypeTemplateArgument( | |||
2188 | S, TemplateParams, NTTP, ArgConst, S.Context.getSizeType(), | |||
2189 | /*ArrayBound=*/true, Info, Deduced); | |||
2190 | } | |||
2191 | ||||
2192 | return DeduceNonTypeTemplateArgument( | |||
2193 | S, TemplateParams, NTTP, (ArgDepMatrix->*GetArgDimensionExpr)(), | |||
| ||||
2194 | Info, Deduced); | |||
2195 | }; | |||
2196 | ||||
2197 | auto Result = DeduceMatrixArg(MatrixParam->getRowExpr(), MatrixArg, | |||
2198 | &ConstantMatrixType::getNumRows, | |||
2199 | &DependentSizedMatrixType::getRowExpr); | |||
2200 | if (Result) | |||
2201 | return Result; | |||
2202 | ||||
2203 | return DeduceMatrixArg(MatrixParam->getColumnExpr(), MatrixArg, | |||
2204 | &ConstantMatrixType::getNumColumns, | |||
2205 | &DependentSizedMatrixType::getColumnExpr); | |||
2206 | } | |||
2207 | ||||
2208 | // (clang extension) | |||
2209 | // | |||
2210 | // T __attribute__(((address_space(N)))) | |||
2211 | case Type::DependentAddressSpace: { | |||
2212 | const DependentAddressSpaceType *AddressSpaceParam = | |||
2213 | cast<DependentAddressSpaceType>(Param); | |||
2214 | ||||
2215 | if (const DependentAddressSpaceType *AddressSpaceArg = | |||
2216 | dyn_cast<DependentAddressSpaceType>(Arg)) { | |||
2217 | // Perform deduction on the pointer type. | |||
2218 | if (Sema::TemplateDeductionResult Result = | |||
2219 | DeduceTemplateArgumentsByTypeMatch( | |||
2220 | S, TemplateParams, AddressSpaceParam->getPointeeType(), | |||
2221 | AddressSpaceArg->getPointeeType(), Info, Deduced, TDF)) | |||
2222 | return Result; | |||
2223 | ||||
2224 | // Perform deduction on the address space, if we can. | |||
2225 | const NonTypeTemplateParmDecl *NTTP = getDeducedParameterFromExpr( | |||
2226 | Info, AddressSpaceParam->getAddrSpaceExpr()); | |||
2227 | if (!NTTP) | |||
2228 | return Sema::TDK_Success; | |||
2229 | ||||
2230 | return DeduceNonTypeTemplateArgument( | |||
2231 | S, TemplateParams, NTTP, AddressSpaceArg->getAddrSpaceExpr(), Info, | |||
2232 | Deduced); | |||
2233 | } | |||
2234 | ||||
2235 | if (isTargetAddressSpace(Arg.getAddressSpace())) { | |||
2236 | llvm::APSInt ArgAddressSpace(S.Context.getTypeSize(S.Context.IntTy), | |||
2237 | false); | |||
2238 | ArgAddressSpace = toTargetAddressSpace(Arg.getAddressSpace()); | |||
2239 | ||||
2240 | // Perform deduction on the pointer types. | |||
2241 | if (Sema::TemplateDeductionResult Result = | |||
2242 | DeduceTemplateArgumentsByTypeMatch( | |||
2243 | S, TemplateParams, AddressSpaceParam->getPointeeType(), | |||
2244 | S.Context.removeAddrSpaceQualType(Arg), Info, Deduced, TDF)) | |||
2245 | return Result; | |||
2246 | ||||
2247 | // Perform deduction on the address space, if we can. | |||
2248 | const NonTypeTemplateParmDecl *NTTP = getDeducedParameterFromExpr( | |||
2249 | Info, AddressSpaceParam->getAddrSpaceExpr()); | |||
2250 | if (!NTTP) | |||
2251 | return Sema::TDK_Success; | |||
2252 | ||||
2253 | return DeduceNonTypeTemplateArgument(S, TemplateParams, NTTP, | |||
2254 | ArgAddressSpace, S.Context.IntTy, | |||
2255 | true, Info, Deduced); | |||
2256 | } | |||
2257 | ||||
2258 | return Sema::TDK_NonDeducedMismatch; | |||
2259 | } | |||
2260 | case Type::DependentExtInt: { | |||
2261 | const auto *IntParam = cast<DependentExtIntType>(Param); | |||
2262 | ||||
2263 | if (const auto *IntArg = dyn_cast<ExtIntType>(Arg)){ | |||
2264 | if (IntParam->isUnsigned() != IntArg->isUnsigned()) | |||
2265 | return Sema::TDK_NonDeducedMismatch; | |||
2266 | ||||
2267 | const NonTypeTemplateParmDecl *NTTP = | |||
2268 | getDeducedParameterFromExpr(Info, IntParam->getNumBitsExpr()); | |||
2269 | if (!NTTP) | |||
2270 | return Sema::TDK_Success; | |||
2271 | ||||
2272 | llvm::APSInt ArgSize(S.Context.getTypeSize(S.Context.IntTy), false); | |||
2273 | ArgSize = IntArg->getNumBits(); | |||
2274 | ||||
2275 | return DeduceNonTypeTemplateArgument(S, TemplateParams, NTTP, ArgSize, | |||
2276 | S.Context.IntTy, true, Info, | |||
2277 | Deduced); | |||
2278 | } | |||
2279 | ||||
2280 | if (const auto *IntArg = dyn_cast<DependentExtIntType>(Arg)) { | |||
2281 | if (IntParam->isUnsigned() != IntArg->isUnsigned()) | |||
2282 | return Sema::TDK_NonDeducedMismatch; | |||
2283 | return Sema::TDK_Success; | |||
2284 | } | |||
2285 | return Sema::TDK_NonDeducedMismatch; | |||
2286 | } | |||
2287 | ||||
2288 | case Type::TypeOfExpr: | |||
2289 | case Type::TypeOf: | |||
2290 | case Type::DependentName: | |||
2291 | case Type::UnresolvedUsing: | |||
2292 | case Type::Decltype: | |||
2293 | case Type::UnaryTransform: | |||
2294 | case Type::Auto: | |||
2295 | case Type::DeducedTemplateSpecialization: | |||
2296 | case Type::DependentTemplateSpecialization: | |||
2297 | case Type::PackExpansion: | |||
2298 | case Type::Pipe: | |||
2299 | // No template argument deduction for these types | |||
2300 | return Sema::TDK_Success; | |||
2301 | } | |||
2302 | ||||
2303 | llvm_unreachable("Invalid Type Class!")::llvm::llvm_unreachable_internal("Invalid Type Class!", "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 2303); | |||
2304 | } | |||
2305 | ||||
2306 | static Sema::TemplateDeductionResult | |||
2307 | DeduceTemplateArguments(Sema &S, | |||
2308 | TemplateParameterList *TemplateParams, | |||
2309 | const TemplateArgument &Param, | |||
2310 | TemplateArgument Arg, | |||
2311 | TemplateDeductionInfo &Info, | |||
2312 | SmallVectorImpl<DeducedTemplateArgument> &Deduced) { | |||
2313 | // If the template argument is a pack expansion, perform template argument | |||
2314 | // deduction against the pattern of that expansion. This only occurs during | |||
2315 | // partial ordering. | |||
2316 | if (Arg.isPackExpansion()) | |||
2317 | Arg = Arg.getPackExpansionPattern(); | |||
2318 | ||||
2319 | switch (Param.getKind()) { | |||
2320 | case TemplateArgument::Null: | |||
2321 | llvm_unreachable("Null template argument in parameter list")::llvm::llvm_unreachable_internal("Null template argument in parameter list" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 2321); | |||
2322 | ||||
2323 | case TemplateArgument::Type: | |||
2324 | if (Arg.getKind() == TemplateArgument::Type) | |||
2325 | return DeduceTemplateArgumentsByTypeMatch(S, TemplateParams, | |||
2326 | Param.getAsType(), | |||
2327 | Arg.getAsType(), | |||
2328 | Info, Deduced, 0); | |||
2329 | Info.FirstArg = Param; | |||
2330 | Info.SecondArg = Arg; | |||
2331 | return Sema::TDK_NonDeducedMismatch; | |||
2332 | ||||
2333 | case TemplateArgument::Template: | |||
2334 | if (Arg.getKind() == TemplateArgument::Template) | |||
2335 | return DeduceTemplateArguments(S, TemplateParams, | |||
2336 | Param.getAsTemplate(), | |||
2337 | Arg.getAsTemplate(), Info, Deduced); | |||
2338 | Info.FirstArg = Param; | |||
2339 | Info.SecondArg = Arg; | |||
2340 | return Sema::TDK_NonDeducedMismatch; | |||
2341 | ||||
2342 | case TemplateArgument::TemplateExpansion: | |||
2343 | llvm_unreachable("caller should handle pack expansions")::llvm::llvm_unreachable_internal("caller should handle pack expansions" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 2343); | |||
2344 | ||||
2345 | case TemplateArgument::Declaration: | |||
2346 | if (Arg.getKind() == TemplateArgument::Declaration && | |||
2347 | isSameDeclaration(Param.getAsDecl(), Arg.getAsDecl())) | |||
2348 | return Sema::TDK_Success; | |||
2349 | ||||
2350 | Info.FirstArg = Param; | |||
2351 | Info.SecondArg = Arg; | |||
2352 | return Sema::TDK_NonDeducedMismatch; | |||
2353 | ||||
2354 | case TemplateArgument::NullPtr: | |||
2355 | if (Arg.getKind() == TemplateArgument::NullPtr && | |||
2356 | S.Context.hasSameType(Param.getNullPtrType(), Arg.getNullPtrType())) | |||
2357 | return Sema::TDK_Success; | |||
2358 | ||||
2359 | Info.FirstArg = Param; | |||
2360 | Info.SecondArg = Arg; | |||
2361 | return Sema::TDK_NonDeducedMismatch; | |||
2362 | ||||
2363 | case TemplateArgument::Integral: | |||
2364 | if (Arg.getKind() == TemplateArgument::Integral) { | |||
2365 | if (hasSameExtendedValue(Param.getAsIntegral(), Arg.getAsIntegral())) | |||
2366 | return Sema::TDK_Success; | |||
2367 | ||||
2368 | Info.FirstArg = Param; | |||
2369 | Info.SecondArg = Arg; | |||
2370 | return Sema::TDK_NonDeducedMismatch; | |||
2371 | } | |||
2372 | ||||
2373 | if (Arg.getKind() == TemplateArgument::Expression) { | |||
2374 | Info.FirstArg = Param; | |||
2375 | Info.SecondArg = Arg; | |||
2376 | return Sema::TDK_NonDeducedMismatch; | |||
2377 | } | |||
2378 | ||||
2379 | Info.FirstArg = Param; | |||
2380 | Info.SecondArg = Arg; | |||
2381 | return Sema::TDK_NonDeducedMismatch; | |||
2382 | ||||
2383 | case TemplateArgument::Expression: | |||
2384 | if (const NonTypeTemplateParmDecl *NTTP = | |||
2385 | getDeducedParameterFromExpr(Info, Param.getAsExpr())) { | |||
2386 | if (Arg.getKind() == TemplateArgument::Integral) | |||
2387 | return DeduceNonTypeTemplateArgument(S, TemplateParams, NTTP, | |||
2388 | Arg.getAsIntegral(), | |||
2389 | Arg.getIntegralType(), | |||
2390 | /*ArrayBound=*/false, | |||
2391 | Info, Deduced); | |||
2392 | if (Arg.getKind() == TemplateArgument::NullPtr) | |||
2393 | return DeduceNullPtrTemplateArgument(S, TemplateParams, NTTP, | |||
2394 | Arg.getNullPtrType(), | |||
2395 | Info, Deduced); | |||
2396 | if (Arg.getKind() == TemplateArgument::Expression) | |||
2397 | return DeduceNonTypeTemplateArgument(S, TemplateParams, NTTP, | |||
2398 | Arg.getAsExpr(), Info, Deduced); | |||
2399 | if (Arg.getKind() == TemplateArgument::Declaration) | |||
2400 | return DeduceNonTypeTemplateArgument(S, TemplateParams, NTTP, | |||
2401 | Arg.getAsDecl(), | |||
2402 | Arg.getParamTypeForDecl(), | |||
2403 | Info, Deduced); | |||
2404 | ||||
2405 | Info.FirstArg = Param; | |||
2406 | Info.SecondArg = Arg; | |||
2407 | return Sema::TDK_NonDeducedMismatch; | |||
2408 | } | |||
2409 | ||||
2410 | // Can't deduce anything, but that's okay. | |||
2411 | return Sema::TDK_Success; | |||
2412 | ||||
2413 | case TemplateArgument::Pack: | |||
2414 | 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-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 2414); | |||
2415 | } | |||
2416 | ||||
2417 | llvm_unreachable("Invalid TemplateArgument Kind!")::llvm::llvm_unreachable_internal("Invalid TemplateArgument Kind!" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 2417); | |||
2418 | } | |||
2419 | ||||
2420 | /// Determine whether there is a template argument to be used for | |||
2421 | /// deduction. | |||
2422 | /// | |||
2423 | /// This routine "expands" argument packs in-place, overriding its input | |||
2424 | /// parameters so that \c Args[ArgIdx] will be the available template argument. | |||
2425 | /// | |||
2426 | /// \returns true if there is another template argument (which will be at | |||
2427 | /// \c Args[ArgIdx]), false otherwise. | |||
2428 | static bool hasTemplateArgumentForDeduction(ArrayRef<TemplateArgument> &Args, | |||
2429 | unsigned &ArgIdx) { | |||
2430 | if (ArgIdx == Args.size()) | |||
2431 | return false; | |||
2432 | ||||
2433 | const TemplateArgument &Arg = Args[ArgIdx]; | |||
2434 | if (Arg.getKind() != TemplateArgument::Pack) | |||
2435 | return true; | |||
2436 | ||||
2437 | 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-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 2437, __PRETTY_FUNCTION__)); | |||
2438 | Args = Arg.pack_elements(); | |||
2439 | ArgIdx = 0; | |||
2440 | return ArgIdx < Args.size(); | |||
2441 | } | |||
2442 | ||||
2443 | /// Determine whether the given set of template arguments has a pack | |||
2444 | /// expansion that is not the last template argument. | |||
2445 | static bool hasPackExpansionBeforeEnd(ArrayRef<TemplateArgument> Args) { | |||
2446 | bool FoundPackExpansion = false; | |||
2447 | for (const auto &A : Args) { | |||
2448 | if (FoundPackExpansion) | |||
2449 | return true; | |||
2450 | ||||
2451 | if (A.getKind() == TemplateArgument::Pack) | |||
2452 | return hasPackExpansionBeforeEnd(A.pack_elements()); | |||
2453 | ||||
2454 | // FIXME: If this is a fixed-arity pack expansion from an outer level of | |||
2455 | // templates, it should not be treated as a pack expansion. | |||
2456 | if (A.isPackExpansion()) | |||
2457 | FoundPackExpansion = true; | |||
2458 | } | |||
2459 | ||||
2460 | return false; | |||
2461 | } | |||
2462 | ||||
2463 | static Sema::TemplateDeductionResult | |||
2464 | DeduceTemplateArguments(Sema &S, TemplateParameterList *TemplateParams, | |||
2465 | ArrayRef<TemplateArgument> Params, | |||
2466 | ArrayRef<TemplateArgument> Args, | |||
2467 | TemplateDeductionInfo &Info, | |||
2468 | SmallVectorImpl<DeducedTemplateArgument> &Deduced, | |||
2469 | bool NumberOfArgumentsMustMatch) { | |||
2470 | // C++0x [temp.deduct.type]p9: | |||
2471 | // If the template argument list of P contains a pack expansion that is not | |||
2472 | // the last template argument, the entire template argument list is a | |||
2473 | // non-deduced context. | |||
2474 | if (hasPackExpansionBeforeEnd(Params)) | |||
2475 | return Sema::TDK_Success; | |||
2476 | ||||
2477 | // C++0x [temp.deduct.type]p9: | |||
2478 | // If P has a form that contains <T> or <i>, then each argument Pi of the | |||
2479 | // respective template argument list P is compared with the corresponding | |||
2480 | // argument Ai of the corresponding template argument list of A. | |||
2481 | unsigned ArgIdx = 0, ParamIdx = 0; | |||
2482 | for (; hasTemplateArgumentForDeduction(Params, ParamIdx); ++ParamIdx) { | |||
2483 | if (!Params[ParamIdx].isPackExpansion()) { | |||
2484 | // The simple case: deduce template arguments by matching Pi and Ai. | |||
2485 | ||||
2486 | // Check whether we have enough arguments. | |||
2487 | if (!hasTemplateArgumentForDeduction(Args, ArgIdx)) | |||
2488 | return NumberOfArgumentsMustMatch | |||
2489 | ? Sema::TDK_MiscellaneousDeductionFailure | |||
2490 | : Sema::TDK_Success; | |||
2491 | ||||
2492 | // C++1z [temp.deduct.type]p9: | |||
2493 | // During partial ordering, if Ai was originally a pack expansion [and] | |||
2494 | // Pi is not a pack expansion, template argument deduction fails. | |||
2495 | if (Args[ArgIdx].isPackExpansion()) | |||
2496 | return Sema::TDK_MiscellaneousDeductionFailure; | |||
2497 | ||||
2498 | // Perform deduction for this Pi/Ai pair. | |||
2499 | if (Sema::TemplateDeductionResult Result | |||
2500 | = DeduceTemplateArguments(S, TemplateParams, | |||
2501 | Params[ParamIdx], Args[ArgIdx], | |||
2502 | Info, Deduced)) | |||
2503 | return Result; | |||
2504 | ||||
2505 | // Move to the next argument. | |||
2506 | ++ArgIdx; | |||
2507 | continue; | |||
2508 | } | |||
2509 | ||||
2510 | // The parameter is a pack expansion. | |||
2511 | ||||
2512 | // C++0x [temp.deduct.type]p9: | |||
2513 | // If Pi is a pack expansion, then the pattern of Pi is compared with | |||
2514 | // each remaining argument in the template argument list of A. Each | |||
2515 | // comparison deduces template arguments for subsequent positions in the | |||
2516 | // template parameter packs expanded by Pi. | |||
2517 | TemplateArgument Pattern = Params[ParamIdx].getPackExpansionPattern(); | |||
2518 | ||||
2519 | // Prepare to deduce the packs within the pattern. | |||
2520 | PackDeductionScope PackScope(S, TemplateParams, Deduced, Info, Pattern); | |||
2521 | ||||
2522 | // Keep track of the deduced template arguments for each parameter pack | |||
2523 | // expanded by this pack expansion (the outer index) and for each | |||
2524 | // template argument (the inner SmallVectors). | |||
2525 | for (; hasTemplateArgumentForDeduction(Args, ArgIdx) && | |||
2526 | PackScope.hasNextElement(); | |||
2527 | ++ArgIdx) { | |||
2528 | // Deduce template arguments from the pattern. | |||
2529 | if (Sema::TemplateDeductionResult Result | |||
2530 | = DeduceTemplateArguments(S, TemplateParams, Pattern, Args[ArgIdx], | |||
2531 | Info, Deduced)) | |||
2532 | return Result; | |||
2533 | ||||
2534 | PackScope.nextPackElement(); | |||
2535 | } | |||
2536 | ||||
2537 | // Build argument packs for each of the parameter packs expanded by this | |||
2538 | // pack expansion. | |||
2539 | if (auto Result = PackScope.finish()) | |||
2540 | return Result; | |||
2541 | } | |||
2542 | ||||
2543 | return Sema::TDK_Success; | |||
2544 | } | |||
2545 | ||||
2546 | static Sema::TemplateDeductionResult | |||
2547 | DeduceTemplateArguments(Sema &S, | |||
2548 | TemplateParameterList *TemplateParams, | |||
2549 | const TemplateArgumentList &ParamList, | |||
2550 | const TemplateArgumentList &ArgList, | |||
2551 | TemplateDeductionInfo &Info, | |||
2552 | SmallVectorImpl<DeducedTemplateArgument> &Deduced) { | |||
2553 | return DeduceTemplateArguments(S, TemplateParams, ParamList.asArray(), | |||
2554 | ArgList.asArray(), Info, Deduced, | |||
2555 | /*NumberOfArgumentsMustMatch*/false); | |||
2556 | } | |||
2557 | ||||
2558 | /// Determine whether two template arguments are the same. | |||
2559 | static bool isSameTemplateArg(ASTContext &Context, | |||
2560 | TemplateArgument X, | |||
2561 | const TemplateArgument &Y, | |||
2562 | bool PackExpansionMatchesPack = false) { | |||
2563 | // If we're checking deduced arguments (X) against original arguments (Y), | |||
2564 | // we will have flattened packs to non-expansions in X. | |||
2565 | if (PackExpansionMatchesPack && X.isPackExpansion() && !Y.isPackExpansion()) | |||
2566 | X = X.getPackExpansionPattern(); | |||
2567 | ||||
2568 | if (X.getKind() != Y.getKind()) | |||
2569 | return false; | |||
2570 | ||||
2571 | switch (X.getKind()) { | |||
2572 | case TemplateArgument::Null: | |||
2573 | llvm_unreachable("Comparing NULL template argument")::llvm::llvm_unreachable_internal("Comparing NULL template argument" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 2573); | |||
2574 | ||||
2575 | case TemplateArgument::Type: | |||
2576 | return Context.getCanonicalType(X.getAsType()) == | |||
2577 | Context.getCanonicalType(Y.getAsType()); | |||
2578 | ||||
2579 | case TemplateArgument::Declaration: | |||
2580 | return isSameDeclaration(X.getAsDecl(), Y.getAsDecl()); | |||
2581 | ||||
2582 | case TemplateArgument::NullPtr: | |||
2583 | return Context.hasSameType(X.getNullPtrType(), Y.getNullPtrType()); | |||
2584 | ||||
2585 | case TemplateArgument::Template: | |||
2586 | case TemplateArgument::TemplateExpansion: | |||
2587 | return Context.getCanonicalTemplateName( | |||
2588 | X.getAsTemplateOrTemplatePattern()).getAsVoidPointer() == | |||
2589 | Context.getCanonicalTemplateName( | |||
2590 | Y.getAsTemplateOrTemplatePattern()).getAsVoidPointer(); | |||
2591 | ||||
2592 | case TemplateArgument::Integral: | |||
2593 | return hasSameExtendedValue(X.getAsIntegral(), Y.getAsIntegral()); | |||
2594 | ||||
2595 | case TemplateArgument::Expression: { | |||
2596 | llvm::FoldingSetNodeID XID, YID; | |||
2597 | X.getAsExpr()->Profile(XID, Context, true); | |||
2598 | Y.getAsExpr()->Profile(YID, Context, true); | |||
2599 | return XID == YID; | |||
2600 | } | |||
2601 | ||||
2602 | case TemplateArgument::Pack: | |||
2603 | if (X.pack_size() != Y.pack_size()) | |||
2604 | return false; | |||
2605 | ||||
2606 | for (TemplateArgument::pack_iterator XP = X.pack_begin(), | |||
2607 | XPEnd = X.pack_end(), | |||
2608 | YP = Y.pack_begin(); | |||
2609 | XP != XPEnd; ++XP, ++YP) | |||
2610 | if (!isSameTemplateArg(Context, *XP, *YP, PackExpansionMatchesPack)) | |||
2611 | return false; | |||
2612 | ||||
2613 | return true; | |||
2614 | } | |||
2615 | ||||
2616 | llvm_unreachable("Invalid TemplateArgument Kind!")::llvm::llvm_unreachable_internal("Invalid TemplateArgument Kind!" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 2616); | |||
2617 | } | |||
2618 | ||||
2619 | /// Allocate a TemplateArgumentLoc where all locations have | |||
2620 | /// been initialized to the given location. | |||
2621 | /// | |||
2622 | /// \param Arg The template argument we are producing template argument | |||
2623 | /// location information for. | |||
2624 | /// | |||
2625 | /// \param NTTPType For a declaration template argument, the type of | |||
2626 | /// the non-type template parameter that corresponds to this template | |||
2627 | /// argument. Can be null if no type sugar is available to add to the | |||
2628 | /// type from the template argument. | |||
2629 | /// | |||
2630 | /// \param Loc The source location to use for the resulting template | |||
2631 | /// argument. | |||
2632 | TemplateArgumentLoc | |||
2633 | Sema::getTrivialTemplateArgumentLoc(const TemplateArgument &Arg, | |||
2634 | QualType NTTPType, SourceLocation Loc) { | |||
2635 | switch (Arg.getKind()) { | |||
2636 | case TemplateArgument::Null: | |||
2637 | 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-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 2637); | |||
2638 | ||||
2639 | case TemplateArgument::Type: | |||
2640 | return TemplateArgumentLoc( | |||
2641 | Arg, Context.getTrivialTypeSourceInfo(Arg.getAsType(), Loc)); | |||
2642 | ||||
2643 | case TemplateArgument::Declaration: { | |||
2644 | if (NTTPType.isNull()) | |||
2645 | NTTPType = Arg.getParamTypeForDecl(); | |||
2646 | Expr *E = BuildExpressionFromDeclTemplateArgument(Arg, NTTPType, Loc) | |||
2647 | .getAs<Expr>(); | |||
2648 | return TemplateArgumentLoc(TemplateArgument(E), E); | |||
2649 | } | |||
2650 | ||||
2651 | case TemplateArgument::NullPtr: { | |||
2652 | if (NTTPType.isNull()) | |||
2653 | NTTPType = Arg.getNullPtrType(); | |||
2654 | Expr *E = BuildExpressionFromDeclTemplateArgument(Arg, NTTPType, Loc) | |||
2655 | .getAs<Expr>(); | |||
2656 | return TemplateArgumentLoc(TemplateArgument(NTTPType, /*isNullPtr*/true), | |||
2657 | E); | |||
2658 | } | |||
2659 | ||||
2660 | case TemplateArgument::Integral: { | |||
2661 | Expr *E = | |||
2662 | BuildExpressionFromIntegralTemplateArgument(Arg, Loc).getAs<Expr>(); | |||
2663 | return TemplateArgumentLoc(TemplateArgument(E), E); | |||
2664 | } | |||
2665 | ||||
2666 | case TemplateArgument::Template: | |||
2667 | case TemplateArgument::TemplateExpansion: { | |||
2668 | NestedNameSpecifierLocBuilder Builder; | |||
2669 | TemplateName Template = Arg.getAsTemplateOrTemplatePattern(); | |||
2670 | if (DependentTemplateName *DTN = Template.getAsDependentTemplateName()) | |||
2671 | Builder.MakeTrivial(Context, DTN->getQualifier(), Loc); | |||
2672 | else if (QualifiedTemplateName *QTN = | |||
2673 | Template.getAsQualifiedTemplateName()) | |||
2674 | Builder.MakeTrivial(Context, QTN->getQualifier(), Loc); | |||
2675 | ||||
2676 | if (Arg.getKind() == TemplateArgument::Template) | |||
2677 | return TemplateArgumentLoc(Context, Arg, | |||
2678 | Builder.getWithLocInContext(Context), Loc); | |||
2679 | ||||
2680 | return TemplateArgumentLoc( | |||
2681 | Context, Arg, Builder.getWithLocInContext(Context), Loc, Loc); | |||
2682 | } | |||
2683 | ||||
2684 | case TemplateArgument::Expression: | |||
2685 | return TemplateArgumentLoc(Arg, Arg.getAsExpr()); | |||
2686 | ||||
2687 | case TemplateArgument::Pack: | |||
2688 | return TemplateArgumentLoc(Arg, TemplateArgumentLocInfo()); | |||
2689 | } | |||
2690 | ||||
2691 | llvm_unreachable("Invalid TemplateArgument Kind!")::llvm::llvm_unreachable_internal("Invalid TemplateArgument Kind!" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 2691); | |||
2692 | } | |||
2693 | ||||
2694 | TemplateArgumentLoc | |||
2695 | Sema::getIdentityTemplateArgumentLoc(NamedDecl *TemplateParm, | |||
2696 | SourceLocation Location) { | |||
2697 | return getTrivialTemplateArgumentLoc( | |||
2698 | Context.getInjectedTemplateArg(TemplateParm), QualType(), Location); | |||
2699 | } | |||
2700 | ||||
2701 | /// Convert the given deduced template argument and add it to the set of | |||
2702 | /// fully-converted template arguments. | |||
2703 | static bool | |||
2704 | ConvertDeducedTemplateArgument(Sema &S, NamedDecl *Param, | |||
2705 | DeducedTemplateArgument Arg, | |||
2706 | NamedDecl *Template, | |||
2707 | TemplateDeductionInfo &Info, | |||
2708 | bool IsDeduced, | |||
2709 | SmallVectorImpl<TemplateArgument> &Output) { | |||
2710 | auto ConvertArg = [&](DeducedTemplateArgument Arg, | |||
2711 | unsigned ArgumentPackIndex) { | |||
2712 | // Convert the deduced template argument into a template | |||
2713 | // argument that we can check, almost as if the user had written | |||
2714 | // the template argument explicitly. | |||
2715 | TemplateArgumentLoc ArgLoc = | |||
2716 | S.getTrivialTemplateArgumentLoc(Arg, QualType(), Info.getLocation()); | |||
2717 | ||||
2718 | // Check the template argument, converting it as necessary. | |||
2719 | return S.CheckTemplateArgument( | |||
2720 | Param, ArgLoc, Template, Template->getLocation(), | |||
2721 | Template->getSourceRange().getEnd(), ArgumentPackIndex, Output, | |||
2722 | IsDeduced | |||
2723 | ? (Arg.wasDeducedFromArrayBound() ? Sema::CTAK_DeducedFromArrayBound | |||
2724 | : Sema::CTAK_Deduced) | |||
2725 | : Sema::CTAK_Specified); | |||
2726 | }; | |||
2727 | ||||
2728 | if (Arg.getKind() == TemplateArgument::Pack) { | |||
2729 | // This is a template argument pack, so check each of its arguments against | |||
2730 | // the template parameter. | |||
2731 | SmallVector<TemplateArgument, 2> PackedArgsBuilder; | |||
2732 | for (const auto &P : Arg.pack_elements()) { | |||
2733 | // When converting the deduced template argument, append it to the | |||
2734 | // general output list. We need to do this so that the template argument | |||
2735 | // checking logic has all of the prior template arguments available. | |||
2736 | DeducedTemplateArgument InnerArg(P); | |||
2737 | InnerArg.setDeducedFromArrayBound(Arg.wasDeducedFromArrayBound()); | |||
2738 | 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-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 2739, __PRETTY_FUNCTION__)) | |||
2739 | "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-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 2739, __PRETTY_FUNCTION__)); | |||
2740 | if (P.isNull()) { | |||
2741 | // We deduced arguments for some elements of this pack, but not for | |||
2742 | // all of them. This happens if we get a conditionally-non-deduced | |||
2743 | // context in a pack expansion (such as an overload set in one of the | |||
2744 | // arguments). | |||
2745 | S.Diag(Param->getLocation(), | |||
2746 | diag::err_template_arg_deduced_incomplete_pack) | |||
2747 | << Arg << Param; | |||
2748 | return true; | |||
2749 | } | |||
2750 | if (ConvertArg(InnerArg, PackedArgsBuilder.size())) | |||
2751 | return true; | |||
2752 | ||||
2753 | // Move the converted template argument into our argument pack. | |||
2754 | PackedArgsBuilder.push_back(Output.pop_back_val()); | |||
2755 | } | |||
2756 | ||||
2757 | // If the pack is empty, we still need to substitute into the parameter | |||
2758 | // itself, in case that substitution fails. | |||
2759 | if (PackedArgsBuilder.empty()) { | |||
2760 | LocalInstantiationScope Scope(S); | |||
2761 | TemplateArgumentList TemplateArgs(TemplateArgumentList::OnStack, Output); | |||
2762 | MultiLevelTemplateArgumentList Args(TemplateArgs); | |||
2763 | ||||
2764 | if (auto *NTTP = dyn_cast<NonTypeTemplateParmDecl>(Param)) { | |||
2765 | Sema::InstantiatingTemplate Inst(S, Template->getLocation(), Template, | |||
2766 | NTTP, Output, | |||
2767 | Template->getSourceRange()); | |||
2768 | if (Inst.isInvalid() || | |||
2769 | S.SubstType(NTTP->getType(), Args, NTTP->getLocation(), | |||
2770 | NTTP->getDeclName()).isNull()) | |||
2771 | return true; | |||
2772 | } else if (auto *TTP = dyn_cast<TemplateTemplateParmDecl>(Param)) { | |||
2773 | Sema::InstantiatingTemplate Inst(S, Template->getLocation(), Template, | |||
2774 | TTP, Output, | |||
2775 | Template->getSourceRange()); | |||
2776 | if (Inst.isInvalid() || !S.SubstDecl(TTP, S.CurContext, Args)) | |||
2777 | return true; | |||
2778 | } | |||
2779 | // For type parameters, no substitution is ever required. | |||
2780 | } | |||
2781 | ||||
2782 | // Create the resulting argument pack. | |||
2783 | Output.push_back( | |||
2784 | TemplateArgument::CreatePackCopy(S.Context, PackedArgsBuilder)); | |||
2785 | return false; | |||
2786 | } | |||
2787 | ||||
2788 | return ConvertArg(Arg, 0); | |||
2789 | } | |||
2790 | ||||
2791 | // FIXME: This should not be a template, but | |||
2792 | // ClassTemplatePartialSpecializationDecl sadly does not derive from | |||
2793 | // TemplateDecl. | |||
2794 | template<typename TemplateDeclT> | |||
2795 | static Sema::TemplateDeductionResult ConvertDeducedTemplateArguments( | |||
2796 | Sema &S, TemplateDeclT *Template, bool IsDeduced, | |||
2797 | SmallVectorImpl<DeducedTemplateArgument> &Deduced, | |||
2798 | TemplateDeductionInfo &Info, SmallVectorImpl<TemplateArgument> &Builder, | |||
2799 | LocalInstantiationScope *CurrentInstantiationScope = nullptr, | |||
2800 | unsigned NumAlreadyConverted = 0, bool PartialOverloading = false) { | |||
2801 | TemplateParameterList *TemplateParams = Template->getTemplateParameters(); | |||
2802 | ||||
2803 | for (unsigned I = 0, N = TemplateParams->size(); I != N; ++I) { | |||
2804 | NamedDecl *Param = TemplateParams->getParam(I); | |||
2805 | ||||
2806 | // C++0x [temp.arg.explicit]p3: | |||
2807 | // A trailing template parameter pack (14.5.3) not otherwise deduced will | |||
2808 | // be deduced to an empty sequence of template arguments. | |||
2809 | // FIXME: Where did the word "trailing" come from? | |||
2810 | if (Deduced[I].isNull() && Param->isTemplateParameterPack()) { | |||
2811 | if (auto Result = | |||
2812 | PackDeductionScope(S, TemplateParams, Deduced, Info, I).finish()) | |||
2813 | return Result; | |||
2814 | } | |||
2815 | ||||
2816 | if (!Deduced[I].isNull()) { | |||
2817 | if (I < NumAlreadyConverted) { | |||
2818 | // We may have had explicitly-specified template arguments for a | |||
2819 | // template parameter pack (that may or may not have been extended | |||
2820 | // via additional deduced arguments). | |||
2821 | if (Param->isParameterPack() && CurrentInstantiationScope && | |||
2822 | CurrentInstantiationScope->getPartiallySubstitutedPack() == Param) { | |||
2823 | // Forget the partially-substituted pack; its substitution is now | |||
2824 | // complete. | |||
2825 | CurrentInstantiationScope->ResetPartiallySubstitutedPack(); | |||
2826 | // We still need to check the argument in case it was extended by | |||
2827 | // deduction. | |||
2828 | } else { | |||
2829 | // We have already fully type-checked and converted this | |||
2830 | // argument, because it was explicitly-specified. Just record the | |||
2831 | // presence of this argument. | |||
2832 | Builder.push_back(Deduced[I]); | |||
2833 | continue; | |||
2834 | } | |||
2835 | } | |||
2836 | ||||
2837 | // We may have deduced this argument, so it still needs to be | |||
2838 | // checked and converted. | |||
2839 | if (ConvertDeducedTemplateArgument(S, Param, Deduced[I], Template, Info, | |||
2840 | IsDeduced, Builder)) { | |||
2841 | Info.Param = makeTemplateParameter(Param); | |||
2842 | // FIXME: These template arguments are temporary. Free them! | |||
2843 | Info.reset(TemplateArgumentList::CreateCopy(S.Context, Builder)); | |||
2844 | return Sema::TDK_SubstitutionFailure; | |||
2845 | } | |||
2846 | ||||
2847 | continue; | |||
2848 | } | |||
2849 | ||||
2850 | // Substitute into the default template argument, if available. | |||
2851 | bool HasDefaultArg = false; | |||
2852 | TemplateDecl *TD = dyn_cast<TemplateDecl>(Template); | |||
2853 | if (!TD) { | |||
2854 | 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-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 2855, __PRETTY_FUNCTION__)) | |||
2855 | 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-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 2855, __PRETTY_FUNCTION__)); | |||
2856 | return Sema::TDK_Incomplete; | |||
2857 | } | |||
2858 | ||||
2859 | TemplateArgumentLoc DefArg = S.SubstDefaultTemplateArgumentIfAvailable( | |||
2860 | TD, TD->getLocation(), TD->getSourceRange().getEnd(), Param, Builder, | |||
2861 | HasDefaultArg); | |||
2862 | ||||
2863 | // If there was no default argument, deduction is incomplete. | |||
2864 | if (DefArg.getArgument().isNull()) { | |||
2865 | Info.Param = makeTemplateParameter( | |||
2866 | const_cast<NamedDecl *>(TemplateParams->getParam(I))); | |||
2867 | Info.reset(TemplateArgumentList::CreateCopy(S.Context, Builder)); | |||
2868 | if (PartialOverloading) break; | |||
2869 | ||||
2870 | return HasDefaultArg ? Sema::TDK_SubstitutionFailure | |||
2871 | : Sema::TDK_Incomplete; | |||
2872 | } | |||
2873 | ||||
2874 | // Check whether we can actually use the default argument. | |||
2875 | if (S.CheckTemplateArgument(Param, DefArg, TD, TD->getLocation(), | |||
2876 | TD->getSourceRange().getEnd(), 0, Builder, | |||
2877 | Sema::CTAK_Specified)) { | |||
2878 | Info.Param = makeTemplateParameter( | |||
2879 | const_cast<NamedDecl *>(TemplateParams->getParam(I))); | |||
2880 | // FIXME: These template arguments are temporary. Free them! | |||
2881 | Info.reset(TemplateArgumentList::CreateCopy(S.Context, Builder)); | |||
2882 | return Sema::TDK_SubstitutionFailure; | |||
2883 | } | |||
2884 | ||||
2885 | // If we get here, we successfully used the default template argument. | |||
2886 | } | |||
2887 | ||||
2888 | return Sema::TDK_Success; | |||
2889 | } | |||
2890 | ||||
2891 | static DeclContext *getAsDeclContextOrEnclosing(Decl *D) { | |||
2892 | if (auto *DC = dyn_cast<DeclContext>(D)) | |||
2893 | return DC; | |||
2894 | return D->getDeclContext(); | |||
2895 | } | |||
2896 | ||||
2897 | template<typename T> struct IsPartialSpecialization { | |||
2898 | static constexpr bool value = false; | |||
2899 | }; | |||
2900 | template<> | |||
2901 | struct IsPartialSpecialization<ClassTemplatePartialSpecializationDecl> { | |||
2902 | static constexpr bool value = true; | |||
2903 | }; | |||
2904 | template<> | |||
2905 | struct IsPartialSpecialization<VarTemplatePartialSpecializationDecl> { | |||
2906 | static constexpr bool value = true; | |||
2907 | }; | |||
2908 | ||||
2909 | template<typename TemplateDeclT> | |||
2910 | static Sema::TemplateDeductionResult | |||
2911 | CheckDeducedArgumentConstraints(Sema& S, TemplateDeclT *Template, | |||
2912 | ArrayRef<TemplateArgument> DeducedArgs, | |||
2913 | TemplateDeductionInfo& Info) { | |||
2914 | llvm::SmallVector<const Expr *, 3> AssociatedConstraints; | |||
2915 | Template->getAssociatedConstraints(AssociatedConstraints); | |||
2916 | if (S.CheckConstraintSatisfaction(Template, AssociatedConstraints, | |||
2917 | DeducedArgs, Info.getLocation(), | |||
2918 | Info.AssociatedConstraintsSatisfaction) || | |||
2919 | !Info.AssociatedConstraintsSatisfaction.IsSatisfied) { | |||
2920 | Info.reset(TemplateArgumentList::CreateCopy(S.Context, DeducedArgs)); | |||
2921 | return Sema::TDK_ConstraintsNotSatisfied; | |||
2922 | } | |||
2923 | return Sema::TDK_Success; | |||
2924 | } | |||
2925 | ||||
2926 | /// Complete template argument deduction for a partial specialization. | |||
2927 | template <typename T> | |||
2928 | static std::enable_if_t<IsPartialSpecialization<T>::value, | |||
2929 | Sema::TemplateDeductionResult> | |||
2930 | FinishTemplateArgumentDeduction( | |||
2931 | Sema &S, T *Partial, bool IsPartialOrdering, | |||
2932 | const TemplateArgumentList &TemplateArgs, | |||
2933 | SmallVectorImpl<DeducedTemplateArgument> &Deduced, | |||
2934 | TemplateDeductionInfo &Info) { | |||
2935 | // Unevaluated SFINAE context. | |||
2936 | EnterExpressionEvaluationContext Unevaluated( | |||
2937 | S, Sema::ExpressionEvaluationContext::Unevaluated); | |||
2938 | Sema::SFINAETrap Trap(S); | |||
2939 | ||||
2940 | Sema::ContextRAII SavedContext(S, getAsDeclContextOrEnclosing(Partial)); | |||
2941 | ||||
2942 | // C++ [temp.deduct.type]p2: | |||
2943 | // [...] or if any template argument remains neither deduced nor | |||
2944 | // explicitly specified, template argument deduction fails. | |||
2945 | SmallVector<TemplateArgument, 4> Builder; | |||
2946 | if (auto Result = ConvertDeducedTemplateArguments( | |||
2947 | S, Partial, IsPartialOrdering, Deduced, Info, Builder)) | |||
2948 | return Result; | |||
2949 | ||||
2950 | // Form the template argument list from the deduced template arguments. | |||
2951 | TemplateArgumentList *DeducedArgumentList | |||
2952 | = TemplateArgumentList::CreateCopy(S.Context, Builder); | |||
2953 | ||||
2954 | Info.reset(DeducedArgumentList); | |||
2955 | ||||
2956 | // Substitute the deduced template arguments into the template | |||
2957 | // arguments of the class template partial specialization, and | |||
2958 | // verify that the instantiated template arguments are both valid | |||
2959 | // and are equivalent to the template arguments originally provided | |||
2960 | // to the class template. | |||
2961 | LocalInstantiationScope InstScope(S); | |||
2962 | auto *Template = Partial->getSpecializedTemplate(); | |||
2963 | const ASTTemplateArgumentListInfo *PartialTemplArgInfo = | |||
2964 | Partial->getTemplateArgsAsWritten(); | |||
2965 | const TemplateArgumentLoc *PartialTemplateArgs = | |||
2966 | PartialTemplArgInfo->getTemplateArgs(); | |||
2967 | ||||
2968 | TemplateArgumentListInfo InstArgs(PartialTemplArgInfo->LAngleLoc, | |||
2969 | PartialTemplArgInfo->RAngleLoc); | |||
2970 | ||||
2971 | if (S.Subst(PartialTemplateArgs, PartialTemplArgInfo->NumTemplateArgs, | |||
2972 | InstArgs, MultiLevelTemplateArgumentList(*DeducedArgumentList))) { | |||
2973 | unsigned ArgIdx = InstArgs.size(), ParamIdx = ArgIdx; | |||
2974 | if (ParamIdx >= Partial->getTemplateParameters()->size()) | |||
2975 | ParamIdx = Partial->getTemplateParameters()->size() - 1; | |||
2976 | ||||
2977 | Decl *Param = const_cast<NamedDecl *>( | |||
2978 | Partial->getTemplateParameters()->getParam(ParamIdx)); | |||
2979 | Info.Param = makeTemplateParameter(Param); | |||
2980 | Info.FirstArg = PartialTemplateArgs[ArgIdx].getArgument(); | |||
2981 | return Sema::TDK_SubstitutionFailure; | |||
2982 | } | |||
2983 | ||||
2984 | bool ConstraintsNotSatisfied; | |||
2985 | SmallVector<TemplateArgument, 4> ConvertedInstArgs; | |||
2986 | if (S.CheckTemplateArgumentList(Template, Partial->getLocation(), InstArgs, | |||
2987 | false, ConvertedInstArgs, | |||
2988 | /*UpdateArgsWithConversions=*/true, | |||
2989 | &ConstraintsNotSatisfied)) | |||
2990 | return ConstraintsNotSatisfied ? Sema::TDK_ConstraintsNotSatisfied : | |||
2991 | Sema::TDK_SubstitutionFailure; | |||
2992 | ||||
2993 | TemplateParameterList *TemplateParams = Template->getTemplateParameters(); | |||
2994 | for (unsigned I = 0, E = TemplateParams->size(); I != E; ++I) { | |||
2995 | TemplateArgument InstArg = ConvertedInstArgs.data()[I]; | |||
2996 | if (!isSameTemplateArg(S.Context, TemplateArgs[I], InstArg)) { | |||
2997 | Info.Param = makeTemplateParameter(TemplateParams->getParam(I)); | |||
2998 | Info.FirstArg = TemplateArgs[I]; | |||
2999 | Info.SecondArg = InstArg; | |||
3000 | return Sema::TDK_NonDeducedMismatch; | |||
3001 | } | |||
3002 | } | |||
3003 | ||||
3004 | if (Trap.hasErrorOccurred()) | |||
3005 | return Sema::TDK_SubstitutionFailure; | |||
3006 | ||||
3007 | if (auto Result = CheckDeducedArgumentConstraints(S, Partial, Builder, Info)) | |||
3008 | return Result; | |||
3009 | ||||
3010 | return Sema::TDK_Success; | |||
3011 | } | |||
3012 | ||||
3013 | /// Complete template argument deduction for a class or variable template, | |||
3014 | /// when partial ordering against a partial specialization. | |||
3015 | // FIXME: Factor out duplication with partial specialization version above. | |||
3016 | static Sema::TemplateDeductionResult FinishTemplateArgumentDeduction( | |||
3017 | Sema &S, TemplateDecl *Template, bool PartialOrdering, | |||
3018 | const TemplateArgumentList &TemplateArgs, | |||
3019 | SmallVectorImpl<DeducedTemplateArgument> &Deduced, | |||
3020 | TemplateDeductionInfo &Info) { | |||
3021 | // Unevaluated SFINAE context. | |||
3022 | EnterExpressionEvaluationContext Unevaluated( | |||
3023 | S, Sema::ExpressionEvaluationContext::Unevaluated); | |||
3024 | Sema::SFINAETrap Trap(S); | |||
3025 | ||||
3026 | Sema::ContextRAII SavedContext(S, getAsDeclContextOrEnclosing(Template)); | |||
3027 | ||||
3028 | // C++ [temp.deduct.type]p2: | |||
3029 | // [...] or if any template argument remains neither deduced nor | |||
3030 | // explicitly specified, template argument deduction fails. | |||
3031 | SmallVector<TemplateArgument, 4> Builder; | |||
3032 | if (auto Result = ConvertDeducedTemplateArguments( | |||
3033 | S, Template, /*IsDeduced*/PartialOrdering, Deduced, Info, Builder)) | |||
3034 | return Result; | |||
3035 | ||||
3036 | // Check that we produced the correct argument list. | |||
3037 | TemplateParameterList *TemplateParams = Template->getTemplateParameters(); | |||
3038 | for (unsigned I = 0, E = TemplateParams->size(); I != E; ++I) { | |||
3039 | TemplateArgument InstArg = Builder[I]; | |||
3040 | if (!isSameTemplateArg(S.Context, TemplateArgs[I], InstArg, | |||
3041 | /*PackExpansionMatchesPack*/true)) { | |||
3042 | Info.Param = makeTemplateParameter(TemplateParams->getParam(I)); | |||
3043 | Info.FirstArg = TemplateArgs[I]; | |||
3044 | Info.SecondArg = InstArg; | |||
3045 | return Sema::TDK_NonDeducedMismatch; | |||
3046 | } | |||
3047 | } | |||
3048 | ||||
3049 | if (Trap.hasErrorOccurred()) | |||
3050 | return Sema::TDK_SubstitutionFailure; | |||
3051 | ||||
3052 | if (auto Result = CheckDeducedArgumentConstraints(S, Template, Builder, | |||
3053 | Info)) | |||
3054 | return Result; | |||
3055 | ||||
3056 | return Sema::TDK_Success; | |||
3057 | } | |||
3058 | ||||
3059 | /// Perform template argument deduction to determine whether | |||
3060 | /// the given template arguments match the given class template | |||
3061 | /// partial specialization per C++ [temp.class.spec.match]. | |||
3062 | Sema::TemplateDeductionResult | |||
3063 | Sema::DeduceTemplateArguments(ClassTemplatePartialSpecializationDecl *Partial, | |||
3064 | const TemplateArgumentList &TemplateArgs, | |||
3065 | TemplateDeductionInfo &Info) { | |||
3066 | if (Partial->isInvalidDecl()) | |||
3067 | return TDK_Invalid; | |||
3068 | ||||
3069 | // C++ [temp.class.spec.match]p2: | |||
3070 | // A partial specialization matches a given actual template | |||
3071 | // argument list if the template arguments of the partial | |||
3072 | // specialization can be deduced from the actual template argument | |||
3073 | // list (14.8.2). | |||
3074 | ||||
3075 | // Unevaluated SFINAE context. | |||
3076 | EnterExpressionEvaluationContext Unevaluated( | |||
3077 | *this, Sema::ExpressionEvaluationContext::Unevaluated); | |||
3078 | SFINAETrap Trap(*this); | |||
3079 | ||||
3080 | SmallVector<DeducedTemplateArgument, 4> Deduced; | |||
3081 | Deduced.resize(Partial->getTemplateParameters()->size()); | |||
3082 | if (TemplateDeductionResult Result | |||
3083 | = ::DeduceTemplateArguments(*this, | |||
3084 | Partial->getTemplateParameters(), | |||
3085 | Partial->getTemplateArgs(), | |||
3086 | TemplateArgs, Info, Deduced)) | |||
3087 | return Result; | |||
3088 | ||||
3089 | SmallVector<TemplateArgument, 4> DeducedArgs(Deduced.begin(), Deduced.end()); | |||
3090 | InstantiatingTemplate Inst(*this, Info.getLocation(), Partial, DeducedArgs, | |||
3091 | Info); | |||
3092 | if (Inst.isInvalid()) | |||
3093 | return TDK_InstantiationDepth; | |||
3094 | ||||
3095 | if (Trap.hasErrorOccurred()) | |||
3096 | return Sema::TDK_SubstitutionFailure; | |||
3097 | ||||
3098 | TemplateDeductionResult Result; | |||
3099 | runWithSufficientStackSpace(Info.getLocation(), [&] { | |||
3100 | Result = ::FinishTemplateArgumentDeduction(*this, Partial, | |||
3101 | /*IsPartialOrdering=*/false, | |||
3102 | TemplateArgs, Deduced, Info); | |||
3103 | }); | |||
3104 | return Result; | |||
3105 | } | |||
3106 | ||||
3107 | /// Perform template argument deduction to determine whether | |||
3108 | /// the given template arguments match the given variable template | |||
3109 | /// partial specialization per C++ [temp.class.spec.match]. | |||
3110 | Sema::TemplateDeductionResult | |||
3111 | Sema::DeduceTemplateArguments(VarTemplatePartialSpecializationDecl *Partial, | |||
3112 | const TemplateArgumentList &TemplateArgs, | |||
3113 | TemplateDeductionInfo &Info) { | |||
3114 | if (Partial->isInvalidDecl()) | |||
3115 | return TDK_Invalid; | |||
3116 | ||||
3117 | // C++ [temp.class.spec.match]p2: | |||
3118 | // A partial specialization matches a given actual template | |||
3119 | // argument list if the template arguments of the partial | |||
3120 | // specialization can be deduced from the actual template argument | |||
3121 | // list (14.8.2). | |||
3122 | ||||
3123 | // Unevaluated SFINAE context. | |||
3124 | EnterExpressionEvaluationContext Unevaluated( | |||
3125 | *this, Sema::ExpressionEvaluationContext::Unevaluated); | |||
3126 | SFINAETrap Trap(*this); | |||
3127 | ||||
3128 | SmallVector<DeducedTemplateArgument, 4> Deduced; | |||
3129 | Deduced.resize(Partial->getTemplateParameters()->size()); | |||
3130 | if (TemplateDeductionResult Result = ::DeduceTemplateArguments( | |||
3131 | *this, Partial->getTemplateParameters(), Partial->getTemplateArgs(), | |||
3132 | TemplateArgs, Info, Deduced)) | |||
3133 | return Result; | |||
3134 | ||||
3135 | SmallVector<TemplateArgument, 4> DeducedArgs(Deduced.begin(), Deduced.end()); | |||
3136 | InstantiatingTemplate Inst(*this, Info.getLocation(), Partial, DeducedArgs, | |||
3137 | Info); | |||
3138 | if (Inst.isInvalid()) | |||
3139 | return TDK_InstantiationDepth; | |||
3140 | ||||
3141 | if (Trap.hasErrorOccurred()) | |||
3142 | return Sema::TDK_SubstitutionFailure; | |||
3143 | ||||
3144 | TemplateDeductionResult Result; | |||
3145 | runWithSufficientStackSpace(Info.getLocation(), [&] { | |||
3146 | Result = ::FinishTemplateArgumentDeduction(*this, Partial, | |||
3147 | /*IsPartialOrdering=*/false, | |||
3148 | TemplateArgs, Deduced, Info); | |||
3149 | }); | |||
3150 | return Result; | |||
3151 | } | |||
3152 | ||||
3153 | /// Determine whether the given type T is a simple-template-id type. | |||
3154 | static bool isSimpleTemplateIdType(QualType T) { | |||
3155 | if (const TemplateSpecializationType *Spec | |||
3156 | = T->getAs<TemplateSpecializationType>()) | |||
3157 | return Spec->getTemplateName().getAsTemplateDecl() != nullptr; | |||
3158 | ||||
3159 | // C++17 [temp.local]p2: | |||
3160 | // the injected-class-name [...] is equivalent to the template-name followed | |||
3161 | // by the template-arguments of the class template specialization or partial | |||
3162 | // specialization enclosed in <> | |||
3163 | // ... which means it's equivalent to a simple-template-id. | |||
3164 | // | |||
3165 | // This only arises during class template argument deduction for a copy | |||
3166 | // deduction candidate, where it permits slicing. | |||
3167 | if (T->getAs<InjectedClassNameType>()) | |||
3168 | return true; | |||
3169 | ||||
3170 | return false; | |||
3171 | } | |||
3172 | ||||
3173 | /// Substitute the explicitly-provided template arguments into the | |||
3174 | /// given function template according to C++ [temp.arg.explicit]. | |||
3175 | /// | |||
3176 | /// \param FunctionTemplate the function template into which the explicit | |||
3177 | /// template arguments will be substituted. | |||
3178 | /// | |||
3179 | /// \param ExplicitTemplateArgs the explicitly-specified template | |||
3180 | /// arguments. | |||
3181 | /// | |||
3182 | /// \param Deduced the deduced template arguments, which will be populated | |||
3183 | /// with the converted and checked explicit template arguments. | |||
3184 | /// | |||
3185 | /// \param ParamTypes will be populated with the instantiated function | |||
3186 | /// parameters. | |||
3187 | /// | |||
3188 | /// \param FunctionType if non-NULL, the result type of the function template | |||
3189 | /// will also be instantiated and the pointed-to value will be updated with | |||
3190 | /// the instantiated function type. | |||
3191 | /// | |||
3192 | /// \param Info if substitution fails for any reason, this object will be | |||
3193 | /// populated with more information about the failure. | |||
3194 | /// | |||
3195 | /// \returns TDK_Success if substitution was successful, or some failure | |||
3196 | /// condition. | |||
3197 | Sema::TemplateDeductionResult | |||
3198 | Sema::SubstituteExplicitTemplateArguments( | |||
3199 | FunctionTemplateDecl *FunctionTemplate, | |||
3200 | TemplateArgumentListInfo &ExplicitTemplateArgs, | |||
3201 | SmallVectorImpl<DeducedTemplateArgument> &Deduced, | |||
3202 | SmallVectorImpl<QualType> &ParamTypes, | |||
3203 | QualType *FunctionType, | |||
3204 | TemplateDeductionInfo &Info) { | |||
3205 | FunctionDecl *Function = FunctionTemplate->getTemplatedDecl(); | |||
3206 | TemplateParameterList *TemplateParams | |||
3207 | = FunctionTemplate->getTemplateParameters(); | |||
3208 | ||||
3209 | if (ExplicitTemplateArgs.size() == 0) { | |||
3210 | // No arguments to substitute; just copy over the parameter types and | |||
3211 | // fill in the function type. | |||
3212 | for (auto P : Function->parameters()) | |||
3213 | ParamTypes.push_back(P->getType()); | |||
3214 | ||||
3215 | if (FunctionType) | |||
3216 | *FunctionType = Function->getType(); | |||
3217 | return TDK_Success; | |||
3218 | } | |||
3219 | ||||
3220 | // Unevaluated SFINAE context. | |||
3221 | EnterExpressionEvaluationContext Unevaluated( | |||
3222 | *this, Sema::ExpressionEvaluationContext::Unevaluated); | |||
3223 | SFINAETrap Trap(*this); | |||
3224 | ||||
3225 | // C++ [temp.arg.explicit]p3: | |||
3226 | // Template arguments that are present shall be specified in the | |||
3227 | // declaration order of their corresponding template-parameters. The | |||
3228 | // template argument list shall not specify more template-arguments than | |||
3229 | // there are corresponding template-parameters. | |||
3230 | SmallVector<TemplateArgument, 4> Builder; | |||
3231 | ||||
3232 | // Enter a new template instantiation context where we check the | |||
3233 | // explicitly-specified template arguments against this function template, | |||
3234 | // and then substitute them into the function parameter types. | |||
3235 | SmallVector<TemplateArgument, 4> DeducedArgs; | |||
3236 | InstantiatingTemplate Inst( | |||
3237 | *this, Info.getLocation(), FunctionTemplate, DeducedArgs, | |||
3238 | CodeSynthesisContext::ExplicitTemplateArgumentSubstitution, Info); | |||
3239 | if (Inst.isInvalid()) | |||
3240 | return TDK_InstantiationDepth; | |||
3241 | ||||
3242 | if (CheckTemplateArgumentList(FunctionTemplate, SourceLocation(), | |||
3243 | ExplicitTemplateArgs, true, Builder, false) || | |||
3244 | Trap.hasErrorOccurred()) { | |||
3245 | unsigned Index = Builder.size(); | |||
3246 | if (Index >= TemplateParams->size()) | |||
3247 | return TDK_SubstitutionFailure; | |||
3248 | Info.Param = makeTemplateParameter(TemplateParams->getParam(Index)); | |||
3249 | return TDK_InvalidExplicitArguments; | |||
3250 | } | |||
3251 | ||||
3252 | // Form the template argument list from the explicitly-specified | |||
3253 | // template arguments. | |||
3254 | TemplateArgumentList *ExplicitArgumentList | |||
3255 | = TemplateArgumentList::CreateCopy(Context, Builder); | |||
3256 | Info.setExplicitArgs(ExplicitArgumentList); | |||
3257 | ||||
3258 | // Template argument deduction and the final substitution should be | |||
3259 | // done in the context of the templated declaration. Explicit | |||
3260 | // argument substitution, on the other hand, needs to happen in the | |||
3261 | // calling context. | |||
3262 | ContextRAII SavedContext(*this, FunctionTemplate->getTemplatedDecl()); | |||
3263 | ||||
3264 | // If we deduced template arguments for a template parameter pack, | |||
3265 | // note that the template argument pack is partially substituted and record | |||
3266 | // the explicit template arguments. They'll be used as part of deduction | |||
3267 | // for this template parameter pack. | |||
3268 | unsigned PartiallySubstitutedPackIndex = -1u; | |||
3269 | if (!Builder.empty()) { | |||
3270 | const TemplateArgument &Arg = Builder.back(); | |||
3271 | if (Arg.getKind() == TemplateArgument::Pack) { | |||
3272 | auto *Param = TemplateParams->getParam(Builder.size() - 1); | |||
3273 | // If this is a fully-saturated fixed-size pack, it should be | |||
3274 | // fully-substituted, not partially-substituted. | |||
3275 | Optional<unsigned> Expansions = getExpandedPackSize(Param); | |||
3276 | if (!Expansions || Arg.pack_size() < *Expansions) { | |||
3277 | PartiallySubstitutedPackIndex = Builder.size() - 1; | |||
3278 | CurrentInstantiationScope->SetPartiallySubstitutedPack( | |||
3279 | Param, Arg.pack_begin(), Arg.pack_size()); | |||
3280 | } | |||
3281 | } | |||
3282 | } | |||
3283 | ||||
3284 | const FunctionProtoType *Proto | |||
3285 | = Function->getType()->getAs<FunctionProtoType>(); | |||
3286 | 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-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 3286, __PRETTY_FUNCTION__)); | |||
3287 | ||||
3288 | // Isolate our substituted parameters from our caller. | |||
3289 | LocalInstantiationScope InstScope(*this, /*MergeWithOuterScope*/true); | |||
3290 | ||||
3291 | ExtParameterInfoBuilder ExtParamInfos; | |||
3292 | ||||
3293 | // Instantiate the types of each of the function parameters given the | |||
3294 | // explicitly-specified template arguments. If the function has a trailing | |||
3295 | // return type, substitute it after the arguments to ensure we substitute | |||
3296 | // in lexical order. | |||
3297 | if (Proto->hasTrailingReturn()) { | |||
3298 | if (SubstParmTypes(Function->getLocation(), Function->parameters(), | |||
3299 | Proto->getExtParameterInfosOrNull(), | |||
3300 | MultiLevelTemplateArgumentList(*ExplicitArgumentList), | |||
3301 | ParamTypes, /*params*/ nullptr, ExtParamInfos)) | |||
3302 | return TDK_SubstitutionFailure; | |||
3303 | } | |||
3304 | ||||
3305 | // Instantiate the return type. | |||
3306 | QualType ResultType; | |||
3307 | { | |||
3308 | // C++11 [expr.prim.general]p3: | |||
3309 | // If a declaration declares a member function or member function | |||
3310 | // template of a class X, the expression this is a prvalue of type | |||
3311 | // "pointer to cv-qualifier-seq X" between the optional cv-qualifer-seq | |||
3312 | // and the end of the function-definition, member-declarator, or | |||
3313 | // declarator. | |||
3314 | Qualifiers ThisTypeQuals; | |||
3315 | CXXRecordDecl *ThisContext = nullptr; | |||
3316 | if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Function)) { | |||
3317 | ThisContext = Method->getParent(); | |||
3318 | ThisTypeQuals = Method->getMethodQualifiers(); | |||
3319 | } | |||
3320 | ||||
3321 | CXXThisScopeRAII ThisScope(*this, ThisContext, ThisTypeQuals, | |||
3322 | getLangOpts().CPlusPlus11); | |||
3323 | ||||
3324 | ResultType = | |||
3325 | SubstType(Proto->getReturnType(), | |||
3326 | MultiLevelTemplateArgumentList(*ExplicitArgumentList), | |||
3327 | Function->getTypeSpecStartLoc(), Function->getDeclName()); | |||
3328 | if (ResultType.isNull() || Trap.hasErrorOccurred()) | |||
3329 | return TDK_SubstitutionFailure; | |||
3330 | // CUDA: Kernel function must have 'void' return type. | |||
3331 | if (getLangOpts().CUDA) | |||
3332 | if (Function->hasAttr<CUDAGlobalAttr>() && !ResultType->isVoidType()) { | |||
3333 | Diag(Function->getLocation(), diag::err_kern_type_not_void_return) | |||
3334 | << Function->getType() << Function->getSourceRange(); | |||
3335 | return TDK_SubstitutionFailure; | |||
3336 | } | |||
3337 | } | |||
3338 | ||||
3339 | // Instantiate the types of each of the function parameters given the | |||
3340 | // explicitly-specified template arguments if we didn't do so earlier. | |||
3341 | if (!Proto->hasTrailingReturn() && | |||
3342 | SubstParmTypes(Function->getLocation(), Function->parameters(), | |||
3343 | Proto->getExtParameterInfosOrNull(), | |||
3344 | MultiLevelTemplateArgumentList(*ExplicitArgumentList), | |||
3345 | ParamTypes, /*params*/ nullptr, ExtParamInfos)) | |||
3346 | return TDK_SubstitutionFailure; | |||
3347 | ||||
3348 | if (FunctionType) { | |||
3349 | auto EPI = Proto->getExtProtoInfo(); | |||
3350 | EPI.ExtParameterInfos = ExtParamInfos.getPointerOrNull(ParamTypes.size()); | |||
3351 | ||||
3352 | // In C++1z onwards, exception specifications are part of the function type, | |||
3353 | // so substitution into the type must also substitute into the exception | |||
3354 | // specification. | |||
3355 | SmallVector<QualType, 4> ExceptionStorage; | |||
3356 | if (getLangOpts().CPlusPlus17 && | |||
3357 | SubstExceptionSpec( | |||
3358 | Function->getLocation(), EPI.ExceptionSpec, ExceptionStorage, | |||
3359 | MultiLevelTemplateArgumentList(*ExplicitArgumentList))) | |||
3360 | return TDK_SubstitutionFailure; | |||
3361 | ||||
3362 | *FunctionType = BuildFunctionType(ResultType, ParamTypes, | |||
3363 | Function->getLocation(), | |||
3364 | Function->getDeclName(), | |||
3365 | EPI); | |||
3366 | if (FunctionType->isNull() || Trap.hasErrorOccurred()) | |||
3367 | return TDK_SubstitutionFailure; | |||
3368 | } | |||
3369 | ||||
3370 | // C++ [temp.arg.explicit]p2: | |||
3371 | // Trailing template arguments that can be deduced (14.8.2) may be | |||
3372 | // omitted from the list of explicit template-arguments. If all of the | |||
3373 | // template arguments can be deduced, they may all be omitted; in this | |||
3374 | // case, the empty template argument list <> itself may also be omitted. | |||
3375 | // | |||
3376 | // Take all of the explicitly-specified arguments and put them into | |||
3377 | // the set of deduced template arguments. The partially-substituted | |||
3378 | // parameter pack, however, will be set to NULL since the deduction | |||
3379 | // mechanism handles the partially-substituted argument pack directly. | |||
3380 | Deduced.reserve(TemplateParams->size()); | |||
3381 | for (unsigned I = 0, N = ExplicitArgumentList->size(); I != N; ++I) { | |||
3382 | const TemplateArgument &Arg = ExplicitArgumentList->get(I); | |||
3383 | if (I == PartiallySubstitutedPackIndex) | |||
3384 | Deduced.push_back(DeducedTemplateArgument()); | |||
3385 | else | |||
3386 | Deduced.push_back(Arg); | |||
3387 | } | |||
3388 | ||||
3389 | return TDK_Success; | |||
3390 | } | |||
3391 | ||||
3392 | /// Check whether the deduced argument type for a call to a function | |||
3393 | /// template matches the actual argument type per C++ [temp.deduct.call]p4. | |||
3394 | static Sema::TemplateDeductionResult | |||
3395 | CheckOriginalCallArgDeduction(Sema &S, TemplateDeductionInfo &Info, | |||
3396 | Sema::OriginalCallArg OriginalArg, | |||
3397 | QualType DeducedA) { | |||
3398 | ASTContext &Context = S.Context; | |||
3399 | ||||
3400 | auto Failed = [&]() -> Sema::TemplateDeductionResult { | |||
3401 | Info.FirstArg = TemplateArgument(DeducedA); | |||
3402 | Info.SecondArg = TemplateArgument(OriginalArg.OriginalArgType); | |||
3403 | Info.CallArgIndex = OriginalArg.ArgIdx; | |||
3404 | return OriginalArg.DecomposedParam ? Sema::TDK_DeducedMismatchNested | |||
3405 | : Sema::TDK_DeducedMismatch; | |||
3406 | }; | |||
3407 | ||||
3408 | QualType A = OriginalArg.OriginalArgType; | |||
3409 | QualType OriginalParamType = OriginalArg.OriginalParamType; | |||
3410 | ||||
3411 | // Check for type equality (top-level cv-qualifiers are ignored). | |||
3412 | if (Context.hasSameUnqualifiedType(A, DeducedA)) | |||
3413 | return Sema::TDK_Success; | |||
3414 | ||||
3415 | // Strip off references on the argument types; they aren't needed for | |||
3416 | // the following checks. | |||
3417 | if (const ReferenceType *DeducedARef = DeducedA->getAs<ReferenceType>()) | |||
3418 | DeducedA = DeducedARef->getPointeeType(); | |||
3419 | if (const ReferenceType *ARef = A->getAs<ReferenceType>()) | |||
3420 | A = ARef->getPointeeType(); | |||
3421 | ||||
3422 | // C++ [temp.deduct.call]p4: | |||
3423 | // [...] However, there are three cases that allow a difference: | |||
3424 | // - If the original P is a reference type, the deduced A (i.e., the | |||
3425 | // type referred to by the reference) can be more cv-qualified than | |||
3426 | // the transformed A. | |||
3427 | if (const ReferenceType *OriginalParamRef | |||
3428 | = OriginalParamType->getAs<ReferenceType>()) { | |||
3429 | // We don't want to keep the reference around any more. | |||
3430 | OriginalParamType = OriginalParamRef->getPointeeType(); | |||
3431 | ||||
3432 | // FIXME: Resolve core issue (no number yet): if the original P is a | |||
3433 | // reference type and the transformed A is function type "noexcept F", | |||
3434 | // the deduced A can be F. | |||
3435 | QualType Tmp; | |||
3436 | if (A->isFunctionType() && S.IsFunctionConversion(A, DeducedA, Tmp)) | |||
3437 | return Sema::TDK_Success; | |||
3438 | ||||
3439 | Qualifiers AQuals = A.getQualifiers(); | |||
3440 | Qualifiers DeducedAQuals = DeducedA.getQualifiers(); | |||
3441 | ||||
3442 | // Under Objective-C++ ARC, the deduced type may have implicitly | |||
3443 | // been given strong or (when dealing with a const reference) | |||
3444 | // unsafe_unretained lifetime. If so, update the original | |||
3445 | // qualifiers to include this lifetime. | |||
3446 | if (S.getLangOpts().ObjCAutoRefCount && | |||
3447 | ((DeducedAQuals.getObjCLifetime() == Qualifiers::OCL_Strong && | |||
3448 | AQuals.getObjCLifetime() == Qualifiers::OCL_None) || | |||
3449 | (DeducedAQuals.hasConst() && | |||
3450 | DeducedAQuals.getObjCLifetime() == Qualifiers::OCL_ExplicitNone))) { | |||
3451 | AQuals.setObjCLifetime(DeducedAQuals.getObjCLifetime()); | |||
3452 | } | |||
3453 | ||||
3454 | if (AQuals == DeducedAQuals) { | |||
3455 | // Qualifiers match; there's nothing to do. | |||
3456 | } else if (!DeducedAQuals.compatiblyIncludes(AQuals)) { | |||
3457 | return Failed(); | |||
3458 | } else { | |||
3459 | // Qualifiers are compatible, so have the argument type adopt the | |||
3460 | // deduced argument type's qualifiers as if we had performed the | |||
3461 | // qualification conversion. | |||
3462 | A = Context.getQualifiedType(A.getUnqualifiedType(), DeducedAQuals); | |||
3463 | } | |||
3464 | } | |||
3465 | ||||
3466 | // - The transformed A can be another pointer or pointer to member | |||
3467 | // type that can be converted to the deduced A via a function pointer | |||
3468 | // conversion and/or a qualification conversion. | |||
3469 | // | |||
3470 | // Also allow conversions which merely strip __attribute__((noreturn)) from | |||
3471 | // function types (recursively). | |||
3472 | bool ObjCLifetimeConversion = false; | |||
3473 | QualType ResultTy; | |||
3474 | if ((A->isAnyPointerType() || A->isMemberPointerType()) && | |||
3475 | (S.IsQualificationConversion(A, DeducedA, false, | |||
3476 | ObjCLifetimeConversion) || | |||
3477 | S.IsFunctionConversion(A, DeducedA, ResultTy))) | |||
3478 | return Sema::TDK_Success; | |||
3479 | ||||
3480 | // - If P is a class and P has the form simple-template-id, then the | |||
3481 | // transformed A can be a derived class of the deduced A. [...] | |||
3482 | // [...] Likewise, if P is a pointer to a class of the form | |||
3483 | // simple-template-id, the transformed A can be a pointer to a | |||
3484 | // derived class pointed to by the deduced A. | |||
3485 | if (const PointerType *OriginalParamPtr | |||
3486 | = OriginalParamType->getAs<PointerType>()) { | |||
3487 | if (const PointerType *DeducedAPtr = DeducedA->getAs<PointerType>()) { | |||
3488 | if (const PointerType *APtr = A->getAs<PointerType>()) { | |||
3489 | if (A->getPointeeType()->isRecordType()) { | |||
3490 | OriginalParamType = OriginalParamPtr->getPointeeType(); | |||
3491 | DeducedA = DeducedAPtr->getPointeeType(); | |||
3492 | A = APtr->getPointeeType(); | |||
3493 | } | |||
3494 | } | |||
3495 | } | |||
3496 | } | |||
3497 | ||||
3498 | if (Context.hasSameUnqualifiedType(A, DeducedA)) | |||
3499 | return Sema::TDK_Success; | |||
3500 | ||||
3501 | if (A->isRecordType() && isSimpleTemplateIdType(OriginalParamType) && | |||
3502 | S.IsDerivedFrom(Info.getLocation(), A, DeducedA)) | |||
3503 | return Sema::TDK_Success; | |||
3504 | ||||
3505 | return Failed(); | |||
3506 | } | |||
3507 | ||||
3508 | /// Find the pack index for a particular parameter index in an instantiation of | |||
3509 | /// a function template with specific arguments. | |||
3510 | /// | |||
3511 | /// \return The pack index for whichever pack produced this parameter, or -1 | |||
3512 | /// if this was not produced by a parameter. Intended to be used as the | |||
3513 | /// ArgumentPackSubstitutionIndex for further substitutions. | |||
3514 | // FIXME: We should track this in OriginalCallArgs so we don't need to | |||
3515 | // reconstruct it here. | |||
3516 | static unsigned getPackIndexForParam(Sema &S, | |||
3517 | FunctionTemplateDecl *FunctionTemplate, | |||
3518 | const MultiLevelTemplateArgumentList &Args, | |||
3519 | unsigned ParamIdx) { | |||
3520 | unsigned Idx = 0; | |||
3521 | for (auto *PD : FunctionTemplate->getTemplatedDecl()->parameters()) { | |||
3522 | if (PD->isParameterPack()) { | |||
3523 | unsigned NumExpansions = | |||
3524 | S.getNumArgumentsInExpansion(PD->getType(), Args).getValueOr(1); | |||
3525 | if (Idx + NumExpansions > ParamIdx) | |||
3526 | return ParamIdx - Idx; | |||
3527 | Idx += NumExpansions; | |||
3528 | } else { | |||
3529 | if (Idx == ParamIdx) | |||
3530 | return -1; // Not a pack expansion | |||
3531 | ++Idx; | |||
3532 | } | |||
3533 | } | |||
3534 | ||||
3535 | 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-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 3535); | |||
3536 | } | |||
3537 | ||||
3538 | /// Finish template argument deduction for a function template, | |||
3539 | /// checking the deduced template arguments for completeness and forming | |||
3540 | /// the function template specialization. | |||
3541 | /// | |||
3542 | /// \param OriginalCallArgs If non-NULL, the original call arguments against | |||
3543 | /// which the deduced argument types should be compared. | |||
3544 | Sema::TemplateDeductionResult Sema::FinishTemplateArgumentDeduction( | |||
3545 | FunctionTemplateDecl *FunctionTemplate, | |||
3546 | SmallVectorImpl<DeducedTemplateArgument> &Deduced, | |||
3547 | unsigned NumExplicitlySpecified, FunctionDecl *&Specialization, | |||
3548 | TemplateDeductionInfo &Info, | |||
3549 | SmallVectorImpl<OriginalCallArg> const *OriginalCallArgs, | |||
3550 | bool PartialOverloading, llvm::function_ref<bool()> CheckNonDependent) { | |||
3551 | // Unevaluated SFINAE context. | |||
3552 | EnterExpressionEvaluationContext Unevaluated( | |||
3553 | *this, Sema::ExpressionEvaluationContext::Unevaluated); | |||
3554 | SFINAETrap Trap(*this); | |||
3555 | ||||
3556 | // Enter a new template instantiation context while we instantiate the | |||
3557 | // actual function declaration. | |||
3558 | SmallVector<TemplateArgument, 4> DeducedArgs(Deduced.begin(), Deduced.end()); | |||
3559 | InstantiatingTemplate Inst( | |||
3560 | *this, Info.getLocation(), FunctionTemplate, DeducedArgs, | |||
3561 | CodeSynthesisContext::DeducedTemplateArgumentSubstitution, Info); | |||
3562 | if (Inst.isInvalid()) | |||
3563 | return TDK_InstantiationDepth; | |||
3564 | ||||
3565 | ContextRAII SavedContext(*this, FunctionTemplate->getTemplatedDecl()); | |||
3566 | ||||
3567 | // C++ [temp.deduct.type]p2: | |||
3568 | // [...] or if any template argument remains neither deduced nor | |||
3569 | // explicitly specified, template argument deduction fails. | |||
3570 | SmallVector<TemplateArgument, 4> Builder; | |||
3571 | if (auto Result = ConvertDeducedTemplateArguments( | |||
3572 | *this, FunctionTemplate, /*IsDeduced*/true, Deduced, Info, Builder, | |||
3573 | CurrentInstantiationScope, NumExplicitlySpecified, | |||
3574 | PartialOverloading)) | |||
3575 | return Result; | |||
3576 | ||||
3577 | // C++ [temp.deduct.call]p10: [DR1391] | |||
3578 | // If deduction succeeds for all parameters that contain | |||
3579 | // template-parameters that participate in template argument deduction, | |||
3580 | // and all template arguments are explicitly specified, deduced, or | |||
3581 | // obtained from default template arguments, remaining parameters are then | |||
3582 | // compared with the corresponding arguments. For each remaining parameter | |||
3583 | // P with a type that was non-dependent before substitution of any | |||
3584 | // explicitly-specified template arguments, if the corresponding argument | |||
3585 | // A cannot be implicitly converted to P, deduction fails. | |||
3586 | if (CheckNonDependent()) | |||
3587 | return TDK_NonDependentConversionFailure; | |||
3588 | ||||
3589 | // Form the template argument list from the deduced template arguments. | |||
3590 | TemplateArgumentList *DeducedArgumentList | |||
3591 | = TemplateArgumentList::CreateCopy(Context, Builder); | |||
3592 | Info.reset(DeducedArgumentList); | |||
3593 | ||||
3594 | // Substitute the deduced template arguments into the function template | |||
3595 | // declaration to produce the function template specialization. | |||
3596 | DeclContext *Owner = FunctionTemplate->getDeclContext(); | |||
3597 | if (FunctionTemplate->getFriendObjectKind()) | |||
3598 | Owner = FunctionTemplate->getLexicalDeclContext(); | |||
3599 | MultiLevelTemplateArgumentList SubstArgs(*DeducedArgumentList); | |||
3600 | Specialization = cast_or_null<FunctionDecl>( | |||
3601 | SubstDecl(FunctionTemplate->getTemplatedDecl(), Owner, SubstArgs)); | |||
3602 | if (!Specialization || Specialization->isInvalidDecl()) | |||
3603 | return TDK_SubstitutionFailure; | |||
3604 | ||||
3605 | assert(Specialization->getPrimaryTemplate()->getCanonicalDecl() ==((Specialization->getPrimaryTemplate()->getCanonicalDecl () == FunctionTemplate->getCanonicalDecl()) ? static_cast< void> (0) : __assert_fail ("Specialization->getPrimaryTemplate()->getCanonicalDecl() == FunctionTemplate->getCanonicalDecl()" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 3606, __PRETTY_FUNCTION__)) | |||
3606 | FunctionTemplate->getCanonicalDecl())((Specialization->getPrimaryTemplate()->getCanonicalDecl () == FunctionTemplate->getCanonicalDecl()) ? static_cast< void> (0) : __assert_fail ("Specialization->getPrimaryTemplate()->getCanonicalDecl() == FunctionTemplate->getCanonicalDecl()" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 3606, __PRETTY_FUNCTION__)); | |||
3607 | ||||
3608 | // If the template argument list is owned by the function template | |||
3609 | // specialization, release it. | |||
3610 | if (Specialization->getTemplateSpecializationArgs() == DeducedArgumentList && | |||
3611 | !Trap.hasErrorOccurred()) | |||
3612 | Info.take(); | |||
3613 | ||||
3614 | // There may have been an error that did not prevent us from constructing a | |||
3615 | // declaration. Mark the declaration invalid and return with a substitution | |||
3616 | // failure. | |||
3617 | if (Trap.hasErrorOccurred()) { | |||
3618 | Specialization->setInvalidDecl(true); | |||
3619 | return TDK_SubstitutionFailure; | |||
3620 | } | |||
3621 | ||||
3622 | // C++2a [temp.deduct]p5 | |||
3623 | // [...] When all template arguments have been deduced [...] all uses of | |||
3624 | // template parameters [...] are replaced with the corresponding deduced | |||
3625 | // or default argument values. | |||
3626 | // [...] If the function template has associated constraints | |||
3627 | // ([temp.constr.decl]), those constraints are checked for satisfaction | |||
3628 | // ([temp.constr.constr]). If the constraints are not satisfied, type | |||
3629 | // deduction fails. | |||
3630 | if (!PartialOverloading || | |||
3631 | (Builder.size() == FunctionTemplate->getTemplateParameters()->size())) { | |||
3632 | if (CheckInstantiatedFunctionTemplateConstraints(Info.getLocation(), | |||
3633 | Specialization, Builder, Info.AssociatedConstraintsSatisfaction)) | |||
3634 | return TDK_MiscellaneousDeductionFailure; | |||
3635 | ||||
3636 | if (!Info.AssociatedConstraintsSatisfaction.IsSatisfied) { | |||
3637 | Info.reset(TemplateArgumentList::CreateCopy(Context, Builder)); | |||
3638 | return TDK_ConstraintsNotSatisfied; | |||
3639 | } | |||
3640 | } | |||
3641 | ||||
3642 | if (OriginalCallArgs) { | |||
3643 | // C++ [temp.deduct.call]p4: | |||
3644 | // In general, the deduction process attempts to find template argument | |||
3645 | // values that will make the deduced A identical to A (after the type A | |||
3646 | // is transformed as described above). [...] | |||
3647 | llvm::SmallDenseMap<std::pair<unsigned, QualType>, QualType> DeducedATypes; | |||
3648 | for (unsigned I = 0, N = OriginalCallArgs->size(); I != N; ++I) { | |||
3649 | OriginalCallArg OriginalArg = (*OriginalCallArgs)[I]; | |||
3650 | ||||
3651 | auto ParamIdx = OriginalArg.ArgIdx; | |||
3652 | if (ParamIdx >= Specialization->getNumParams()) | |||
3653 | // FIXME: This presumably means a pack ended up smaller than we | |||
3654 | // expected while deducing. Should this not result in deduction | |||
3655 | // failure? Can it even happen? | |||
3656 | continue; | |||
3657 | ||||
3658 | QualType DeducedA; | |||
3659 | if (!OriginalArg.DecomposedParam) { | |||
3660 | // P is one of the function parameters, just look up its substituted | |||
3661 | // type. | |||
3662 | DeducedA = Specialization->getParamDecl(ParamIdx)->getType(); | |||
3663 | } else { | |||
3664 | // P is a decomposed element of a parameter corresponding to a | |||
3665 | // braced-init-list argument. Substitute back into P to find the | |||
3666 | // deduced A. | |||
3667 | QualType &CacheEntry = | |||
3668 | DeducedATypes[{ParamIdx, OriginalArg.OriginalParamType}]; | |||
3669 | if (CacheEntry.isNull()) { | |||
3670 | ArgumentPackSubstitutionIndexRAII PackIndex( | |||
3671 | *this, getPackIndexForParam(*this, FunctionTemplate, SubstArgs, | |||
3672 | ParamIdx)); | |||
3673 | CacheEntry = | |||
3674 | SubstType(OriginalArg.OriginalParamType, SubstArgs, | |||
3675 | Specialization->getTypeSpecStartLoc(), | |||
3676 | Specialization->getDeclName()); | |||
3677 | } | |||
3678 | DeducedA = CacheEntry; | |||
3679 | } | |||
3680 | ||||
3681 | if (auto TDK = | |||
3682 | CheckOriginalCallArgDeduction(*this, Info, OriginalArg, DeducedA)) | |||
3683 | return TDK; | |||
3684 | } | |||
3685 | } | |||
3686 | ||||
3687 | // If we suppressed any diagnostics while performing template argument | |||
3688 | // deduction, and if we haven't already instantiated this declaration, | |||
3689 | // keep track of these diagnostics. They'll be emitted if this specialization | |||
3690 | // is actually used. | |||
3691 | if (Info.diag_begin() != Info.diag_end()) { | |||
3692 | SuppressedDiagnosticsMap::iterator | |||
3693 | Pos = SuppressedDiagnostics.find(Specialization->getCanonicalDecl()); | |||
3694 | if (Pos == SuppressedDiagnostics.end()) | |||
3695 | SuppressedDiagnostics[Specialization->getCanonicalDecl()] | |||
3696 | .append(Info.diag_begin(), Info.diag_end()); | |||
3697 | } | |||
3698 | ||||
3699 | return TDK_Success; | |||
3700 | } | |||
3701 | ||||
3702 | /// Gets the type of a function for template-argument-deducton | |||
3703 | /// purposes when it's considered as part of an overload set. | |||
3704 | static QualType GetTypeOfFunction(Sema &S, const OverloadExpr::FindResult &R, | |||
3705 | FunctionDecl *Fn) { | |||
3706 | // We may need to deduce the return type of the function now. | |||
3707 | if (S.getLangOpts().CPlusPlus14 && Fn->getReturnType()->isUndeducedType() && | |||
3708 | S.DeduceReturnType(Fn, R.Expression->getExprLoc(), /*Diagnose*/ false)) | |||
3709 | return {}; | |||
3710 | ||||
3711 | if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Fn)) | |||
3712 | if (Method->isInstance()) { | |||
3713 | // An instance method that's referenced in a form that doesn't | |||
3714 | // look like a member pointer is just invalid. | |||
3715 | if (!R.HasFormOfMemberPointer) | |||
3716 | return {}; | |||
3717 | ||||
3718 | return S.Context.getMemberPointerType(Fn->getType(), | |||
3719 | S.Context.getTypeDeclType(Method->getParent()).getTypePtr()); | |||
3720 | } | |||
3721 | ||||
3722 | if (!R.IsAddressOfOperand) return Fn->getType(); | |||
3723 | return S.Context.getPointerType(Fn->getType()); | |||
3724 | } | |||
3725 | ||||
3726 | /// Apply the deduction rules for overload sets. | |||
3727 | /// | |||
3728 | /// \return the null type if this argument should be treated as an | |||
3729 | /// undeduced context | |||
3730 | static QualType | |||
3731 | ResolveOverloadForDeduction(Sema &S, TemplateParameterList *TemplateParams, | |||
3732 | Expr *Arg, QualType ParamType, | |||
3733 | bool ParamWasReference) { | |||
3734 | ||||
3735 | OverloadExpr::FindResult R = OverloadExpr::find(Arg); | |||
3736 | ||||
3737 | OverloadExpr *Ovl = R.Expression; | |||
3738 | ||||
3739 | // C++0x [temp.deduct.call]p4 | |||
3740 | unsigned TDF = 0; | |||
3741 | if (ParamWasReference) | |||
3742 | TDF |= TDF_ParamWithReferenceType; | |||
3743 | if (R.IsAddressOfOperand) | |||
3744 | TDF |= TDF_IgnoreQualifiers; | |||
3745 | ||||
3746 | // C++0x [temp.deduct.call]p6: | |||
3747 | // When P is a function type, pointer to function type, or pointer | |||
3748 | // to member function type: | |||
3749 | ||||
3750 | if (!ParamType->isFunctionType() && | |||
3751 | !ParamType->isFunctionPointerType() && | |||
3752 | !ParamType->isMemberFunctionPointerType()) { | |||
3753 | if (Ovl->hasExplicitTemplateArgs()) { | |||
3754 | // But we can still look for an explicit specialization. | |||
3755 | if (FunctionDecl *ExplicitSpec | |||
3756 | = S.ResolveSingleFunctionTemplateSpecialization(Ovl)) | |||
3757 | return GetTypeOfFunction(S, R, ExplicitSpec); | |||
3758 | } | |||
3759 | ||||
3760 | DeclAccessPair DAP; | |||
3761 | if (FunctionDecl *Viable = | |||
3762 | S.resolveAddressOfSingleOverloadCandidate(Arg, DAP)) | |||
3763 | return GetTypeOfFunction(S, R, Viable); | |||
3764 | ||||
3765 | return {}; | |||
3766 | } | |||
3767 | ||||
3768 | // Gather the explicit template arguments, if any. | |||
3769 | TemplateArgumentListInfo ExplicitTemplateArgs; | |||
3770 | if (Ovl->hasExplicitTemplateArgs()) | |||
3771 | Ovl->copyTemplateArgumentsInto(ExplicitTemplateArgs); | |||
3772 | QualType Match; | |||
3773 | for (UnresolvedSetIterator I = Ovl->decls_begin(), | |||
3774 | E = Ovl->decls_end(); I != E; ++I) { | |||
3775 | NamedDecl *D = (*I)->getUnderlyingDecl(); | |||
3776 | ||||
3777 | if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(D)) { | |||
3778 | // - If the argument is an overload set containing one or more | |||
3779 | // function templates, the parameter is treated as a | |||
3780 | // non-deduced context. | |||
3781 | if (!Ovl->hasExplicitTemplateArgs()) | |||
3782 | return {}; | |||
3783 | ||||
3784 | // Otherwise, see if we can resolve a function type | |||
3785 | FunctionDecl *Specialization = nullptr; | |||
3786 | TemplateDeductionInfo Info(Ovl->getNameLoc()); | |||
3787 | if (S.DeduceTemplateArguments(FunTmpl, &ExplicitTemplateArgs, | |||
3788 | Specialization, Info)) | |||
3789 | continue; | |||
3790 | ||||
3791 | D = Specialization; | |||
3792 | } | |||
3793 | ||||
3794 | FunctionDecl *Fn = cast<FunctionDecl>(D); | |||
3795 | QualType ArgType = GetTypeOfFunction(S, R, Fn); | |||
3796 | if (ArgType.isNull()) continue; | |||
3797 | ||||
3798 | // Function-to-pointer conversion. | |||
3799 | if (!ParamWasReference && ParamType->isPointerType() && | |||
3800 | ArgType->isFunctionType()) | |||
3801 | ArgType = S.Context.getPointerType(ArgType); | |||
3802 | ||||
3803 | // - If the argument is an overload set (not containing function | |||
3804 | // templates), trial argument deduction is attempted using each | |||
3805 | // of the members of the set. If deduction succeeds for only one | |||
3806 | // of the overload set members, that member is used as the | |||
3807 | // argument value for the deduction. If deduction succeeds for | |||
3808 | // more than one member of the overload set the parameter is | |||
3809 | // treated as a non-deduced context. | |||
3810 | ||||
3811 | // We do all of this in a fresh context per C++0x [temp.deduct.type]p2: | |||
3812 | // Type deduction is done independently for each P/A pair, and | |||
3813 | // the deduced template argument values are then combined. | |||
3814 | // So we do not reject deductions which were made elsewhere. | |||
3815 | SmallVector<DeducedTemplateArgument, 8> | |||
3816 | Deduced(TemplateParams->size()); | |||
3817 | TemplateDeductionInfo Info(Ovl->getNameLoc()); | |||
3818 | Sema::TemplateDeductionResult Result | |||
3819 | = DeduceTemplateArgumentsByTypeMatch(S, TemplateParams, ParamType, | |||
3820 | ArgType, Info, Deduced, TDF); | |||
3821 | if (Result) continue; | |||
3822 | if (!Match.isNull()) | |||
3823 | return {}; | |||
3824 | Match = ArgType; | |||
3825 | } | |||
3826 | ||||
3827 | return Match; | |||
3828 | } | |||
3829 | ||||
3830 | /// Perform the adjustments to the parameter and argument types | |||
3831 | /// described in C++ [temp.deduct.call]. | |||
3832 | /// | |||
3833 | /// \returns true if the caller should not attempt to perform any template | |||
3834 | /// argument deduction based on this P/A pair because the argument is an | |||
3835 | /// overloaded function set that could not be resolved. | |||
3836 | static bool AdjustFunctionParmAndArgTypesForDeduction( | |||
3837 | Sema &S, TemplateParameterList *TemplateParams, unsigned FirstInnerIndex, | |||
3838 | QualType &ParamType, QualType &ArgType, Expr *Arg, unsigned &TDF) { | |||
3839 | // C++0x [temp.deduct.call]p3: | |||
3840 | // If P is a cv-qualified type, the top level cv-qualifiers of P's type | |||
3841 | // are ignored for type deduction. | |||
3842 | if (ParamType.hasQualifiers()) | |||
3843 | ParamType = ParamType.getUnqualifiedType(); | |||
3844 | ||||
3845 | // [...] If P is a reference type, the type referred to by P is | |||
3846 | // used for type deduction. | |||
3847 | const ReferenceType *ParamRefType = ParamType->getAs<ReferenceType>(); | |||
3848 | if (ParamRefType) | |||
3849 | ParamType = ParamRefType->getPointeeType(); | |||
3850 | ||||
3851 | // Overload sets usually make this parameter an undeduced context, | |||
3852 | // but there are sometimes special circumstances. Typically | |||
3853 | // involving a template-id-expr. | |||
3854 | if (ArgType == S.Context.OverloadTy) { | |||
3855 | ArgType = ResolveOverloadForDeduction(S, TemplateParams, | |||
3856 | Arg, ParamType, | |||
3857 | ParamRefType != nullptr); | |||
3858 | if (ArgType.isNull()) | |||
3859 | return true; | |||
3860 | } | |||
3861 | ||||
3862 | if (ParamRefType) { | |||
3863 | // If the argument has incomplete array type, try to complete its type. | |||
3864 | if (ArgType->isIncompleteArrayType()) | |||
3865 | ArgType = S.getCompletedType(Arg); | |||
3866 | ||||
3867 | // C++1z [temp.deduct.call]p3: | |||
3868 | // If P is a forwarding reference and the argument is an lvalue, the type | |||
3869 | // "lvalue reference to A" is used in place of A for type deduction. | |||
3870 | if (isForwardingReference(QualType(ParamRefType, 0), FirstInnerIndex) && | |||
3871 | Arg->isLValue()) { | |||
3872 | if (S.getLangOpts().OpenCL) | |||
3873 | ArgType = S.Context.getAddrSpaceQualType(ArgType, LangAS::opencl_generic); | |||
3874 | ArgType = S.Context.getLValueReferenceType(ArgType); | |||
3875 | } | |||
3876 | } else { | |||
3877 | // C++ [temp.deduct.call]p2: | |||
3878 | // If P is not a reference type: | |||
3879 | // - If A is an array type, the pointer type produced by the | |||
3880 | // array-to-pointer standard conversion (4.2) is used in place of | |||
3881 | // A for type deduction; otherwise, | |||
3882 | if (ArgType->isArrayType()) | |||
3883 | ArgType = S.Context.getArrayDecayedType(ArgType); | |||
3884 | // - If A is a function type, the pointer type produced by the | |||
3885 | // function-to-pointer standard conversion (4.3) is used in place | |||
3886 | // of A for type deduction; otherwise, | |||
3887 | else if (ArgType->isFunctionType()) | |||
3888 | ArgType = S.Context.getPointerType(ArgType); | |||
3889 | else { | |||
3890 | // - If A is a cv-qualified type, the top level cv-qualifiers of A's | |||
3891 | // type are ignored for type deduction. | |||
3892 | ArgType = ArgType.getUnqualifiedType(); | |||
3893 | } | |||
3894 | } | |||
3895 | ||||
3896 | // C++0x [temp.deduct.call]p4: | |||
3897 | // In general, the deduction process attempts to find template argument | |||
3898 | // values that will make the deduced A identical to A (after the type A | |||
3899 | // is transformed as described above). [...] | |||
3900 | TDF = TDF_SkipNonDependent; | |||
3901 | ||||
3902 | // - If the original P is a reference type, the deduced A (i.e., the | |||
3903 | // type referred to by the reference) can be more cv-qualified than | |||
3904 | // the transformed A. | |||
3905 | if (ParamRefType) | |||
3906 | TDF |= TDF_ParamWithReferenceType; | |||
3907 | // - The transformed A can be another pointer or pointer to member | |||
3908 | // type that can be converted to the deduced A via a qualification | |||
3909 | // conversion (4.4). | |||
3910 | if (ArgType->isPointerType() || ArgType->isMemberPointerType() || | |||
3911 | ArgType->isObjCObjectPointerType()) | |||
3912 | TDF |= TDF_IgnoreQualifiers; | |||
3913 | // - If P is a class and P has the form simple-template-id, then the | |||
3914 | // transformed A can be a derived class of the deduced A. Likewise, | |||
3915 | // if P is a pointer to a class of the form simple-template-id, the | |||
3916 | // transformed A can be a pointer to a derived class pointed to by | |||
3917 | // the deduced A. | |||
3918 | if (isSimpleTemplateIdType(ParamType) || | |||
3919 | (isa<PointerType>(ParamType) && | |||
3920 | isSimpleTemplateIdType( | |||
3921 | ParamType->getAs<PointerType>()->getPointeeType()))) | |||
3922 | TDF |= TDF_DerivedClass; | |||
3923 | ||||
3924 | return false; | |||
3925 | } | |||
3926 | ||||
3927 | static bool | |||
3928 | hasDeducibleTemplateParameters(Sema &S, FunctionTemplateDecl *FunctionTemplate, | |||
3929 | QualType T); | |||
3930 | ||||
3931 | static Sema::TemplateDeductionResult DeduceTemplateArgumentsFromCallArgument( | |||
3932 | Sema &S, TemplateParameterList *TemplateParams, unsigned FirstInnerIndex, | |||
3933 | QualType ParamType, Expr *Arg, TemplateDeductionInfo &Info, | |||
3934 | SmallVectorImpl<DeducedTemplateArgument> &Deduced, | |||
3935 | SmallVectorImpl<Sema::OriginalCallArg> &OriginalCallArgs, | |||
3936 | bool DecomposedParam, unsigned ArgIdx, unsigned TDF); | |||
3937 | ||||
3938 | /// Attempt template argument deduction from an initializer list | |||
3939 | /// deemed to be an argument in a function call. | |||
3940 | static Sema::TemplateDeductionResult DeduceFromInitializerList( | |||
3941 | Sema &S, TemplateParameterList *TemplateParams, QualType AdjustedParamType, | |||
3942 | InitListExpr *ILE, TemplateDeductionInfo &Info, | |||
3943 | SmallVectorImpl<DeducedTemplateArgument> &Deduced, | |||
3944 | SmallVectorImpl<Sema::OriginalCallArg> &OriginalCallArgs, unsigned ArgIdx, | |||
3945 | unsigned TDF) { | |||
3946 | // C++ [temp.deduct.call]p1: (CWG 1591) | |||
3947 | // If removing references and cv-qualifiers from P gives | |||
3948 | // std::initializer_list<P0> or P0[N] for some P0 and N and the argument is | |||
3949 | // a non-empty initializer list, then deduction is performed instead for | |||
3950 | // each element of the initializer list, taking P0 as a function template | |||
3951 | // parameter type and the initializer element as its argument | |||
3952 | // | |||
3953 | // We've already removed references and cv-qualifiers here. | |||
3954 | if (!ILE->getNumInits()) | |||
3955 | return Sema::TDK_Success; | |||
3956 | ||||
3957 | QualType ElTy; | |||
3958 | auto *ArrTy = S.Context.getAsArrayType(AdjustedParamType); | |||
3959 | if (ArrTy) | |||
3960 | ElTy = ArrTy->getElementType(); | |||
3961 | else if (!S.isStdInitializerList(AdjustedParamType, &ElTy)) { | |||
3962 | // Otherwise, an initializer list argument causes the parameter to be | |||
3963 | // considered a non-deduced context | |||
3964 | return Sema::TDK_Success; | |||
3965 | } | |||
3966 | ||||
3967 | // Resolving a core issue: a braced-init-list containing any designators is | |||
3968 | // a non-deduced context. | |||
3969 | for (Expr *E : ILE->inits()) | |||
3970 | if (isa<DesignatedInitExpr>(E)) | |||
3971 | return Sema::TDK_Success; | |||
3972 | ||||
3973 | // Deduction only needs to be done for dependent types. | |||
3974 | if (ElTy->isDependentType()) { | |||
3975 | for (Expr *E : ILE->inits()) { | |||
3976 | if (auto Result = DeduceTemplateArgumentsFromCallArgument( | |||
3977 | S, TemplateParams, 0, ElTy, E, Info, Deduced, OriginalCallArgs, true, | |||
3978 | ArgIdx, TDF)) | |||
3979 | return Result; | |||
3980 | } | |||
3981 | } | |||
3982 | ||||
3983 | // in the P0[N] case, if N is a non-type template parameter, N is deduced | |||
3984 | // from the length of the initializer list. | |||
3985 | if (auto *DependentArrTy = dyn_cast_or_null<DependentSizedArrayType>(ArrTy)) { | |||
3986 | // Determine the array bound is something we can deduce. | |||
3987 | if (const NonTypeTemplateParmDecl *NTTP = | |||
3988 | getDeducedParameterFromExpr(Info, DependentArrTy->getSizeExpr())) { | |||
3989 | // We can perform template argument deduction for the given non-type | |||
3990 | // template parameter. | |||
3991 | // C++ [temp.deduct.type]p13: | |||
3992 | // The type of N in the type T[N] is std::size_t. | |||
3993 | QualType T = S.Context.getSizeType(); | |||
3994 | llvm::APInt Size(S.Context.getIntWidth(T), ILE->getNumInits()); | |||
3995 | if (auto Result = DeduceNonTypeTemplateArgument( | |||
3996 | S, TemplateParams, NTTP, llvm::APSInt(Size), T, | |||
3997 | /*ArrayBound=*/true, Info, Deduced)) | |||
3998 | return Result; | |||
3999 | } | |||
4000 | } | |||
4001 | ||||
4002 | return Sema::TDK_Success; | |||
4003 | } | |||
4004 | ||||
4005 | /// Perform template argument deduction per [temp.deduct.call] for a | |||
4006 | /// single parameter / argument pair. | |||
4007 | static Sema::TemplateDeductionResult DeduceTemplateArgumentsFromCallArgument( | |||
4008 | Sema &S, TemplateParameterList *TemplateParams, unsigned FirstInnerIndex, | |||
4009 | QualType ParamType, Expr *Arg, TemplateDeductionInfo &Info, | |||
4010 | SmallVectorImpl<DeducedTemplateArgument> &Deduced, | |||
4011 | SmallVectorImpl<Sema::OriginalCallArg> &OriginalCallArgs, | |||
4012 | bool DecomposedParam, unsigned ArgIdx, unsigned TDF) { | |||
4013 | QualType ArgType = Arg->getType(); | |||
4014 | QualType OrigParamType = ParamType; | |||
4015 | ||||
4016 | // If P is a reference type [...] | |||
4017 | // If P is a cv-qualified type [...] | |||
4018 | if (AdjustFunctionParmAndArgTypesForDeduction( | |||
4019 | S, TemplateParams, FirstInnerIndex, ParamType, ArgType, Arg, TDF)) | |||
4020 | return Sema::TDK_Success; | |||
4021 | ||||
4022 | // If [...] the argument is a non-empty initializer list [...] | |||
4023 | if (InitListExpr *ILE = dyn_cast<InitListExpr>(Arg)) | |||
4024 | return DeduceFromInitializerList(S, TemplateParams, ParamType, ILE, Info, | |||
4025 | Deduced, OriginalCallArgs, ArgIdx, TDF); | |||
4026 | ||||
4027 | // [...] the deduction process attempts to find template argument values | |||
4028 | // that will make the deduced A identical to A | |||
4029 | // | |||
4030 | // Keep track of the argument type and corresponding parameter index, | |||
4031 | // so we can check for compatibility between the deduced A and A. | |||
4032 | OriginalCallArgs.push_back( | |||
4033 | Sema::OriginalCallArg(OrigParamType, DecomposedParam, ArgIdx, ArgType)); | |||
4034 | return DeduceTemplateArgumentsByTypeMatch(S, TemplateParams, ParamType, | |||
4035 | ArgType, Info, Deduced, TDF); | |||
4036 | } | |||
4037 | ||||
4038 | /// Perform template argument deduction from a function call | |||
4039 | /// (C++ [temp.deduct.call]). | |||
4040 | /// | |||
4041 | /// \param FunctionTemplate the function template for which we are performing | |||
4042 | /// template argument deduction. | |||
4043 | /// | |||
4044 | /// \param ExplicitTemplateArgs the explicit template arguments provided | |||
4045 | /// for this call. | |||
4046 | /// | |||
4047 | /// \param Args the function call arguments | |||
4048 | /// | |||
4049 | /// \param Specialization if template argument deduction was successful, | |||
4050 | /// this will be set to the function template specialization produced by | |||
4051 | /// template argument deduction. | |||
4052 | /// | |||
4053 | /// \param Info the argument will be updated to provide additional information | |||
4054 | /// about template argument deduction. | |||
4055 | /// | |||
4056 | /// \param CheckNonDependent A callback to invoke to check conversions for | |||
4057 | /// non-dependent parameters, between deduction and substitution, per DR1391. | |||
4058 | /// If this returns true, substitution will be skipped and we return | |||
4059 | /// TDK_NonDependentConversionFailure. The callback is passed the parameter | |||
4060 | /// types (after substituting explicit template arguments). | |||
4061 | /// | |||
4062 | /// \returns the result of template argument deduction. | |||
4063 | Sema::TemplateDeductionResult Sema::DeduceTemplateArguments( | |||
4064 | FunctionTemplateDecl *FunctionTemplate, | |||
4065 | TemplateArgumentListInfo *ExplicitTemplateArgs, ArrayRef<Expr *> Args, | |||
4066 | FunctionDecl *&Specialization, TemplateDeductionInfo &Info, | |||
4067 | bool PartialOverloading, | |||
4068 | llvm::function_ref<bool(ArrayRef<QualType>)> CheckNonDependent) { | |||
4069 | if (FunctionTemplate->isInvalidDecl()) | |||
4070 | return TDK_Invalid; | |||
4071 | ||||
4072 | FunctionDecl *Function = FunctionTemplate->getTemplatedDecl(); | |||
4073 | unsigned NumParams = Function->getNumParams(); | |||
4074 | ||||
4075 | unsigned FirstInnerIndex = getFirstInnerIndex(FunctionTemplate); | |||
4076 | ||||
4077 | // C++ [temp.deduct.call]p1: | |||
4078 | // Template argument deduction is done by comparing each function template | |||
4079 | // parameter type (call it P) with the type of the corresponding argument | |||
4080 | // of the call (call it A) as described below. | |||
4081 | if (Args.size() < Function->getMinRequiredArguments() && !PartialOverloading) | |||
4082 | return TDK_TooFewArguments; | |||
4083 | else if (TooManyArguments(NumParams, Args.size(), PartialOverloading)) { | |||
4084 | const auto *Proto = Function->getType()->castAs<FunctionProtoType>(); | |||
4085 | if (Proto->isTemplateVariadic()) | |||
4086 | /* Do nothing */; | |||
4087 | else if (!Proto->isVariadic()) | |||
4088 | return TDK_TooManyArguments; | |||
4089 | } | |||
4090 | ||||
4091 | // The types of the parameters from which we will perform template argument | |||
4092 | // deduction. | |||
4093 | LocalInstantiationScope InstScope(*this); | |||
4094 | TemplateParameterList *TemplateParams | |||
4095 | = FunctionTemplate->getTemplateParameters(); | |||
4096 | SmallVector<DeducedTemplateArgument, 4> Deduced; | |||
4097 | SmallVector<QualType, 8> ParamTypes; | |||
4098 | unsigned NumExplicitlySpecified = 0; | |||
4099 | if (ExplicitTemplateArgs) { | |||
4100 | TemplateDeductionResult Result; | |||
4101 | runWithSufficientStackSpace(Info.getLocation(), [&] { | |||
4102 | Result = SubstituteExplicitTemplateArguments( | |||
4103 | FunctionTemplate, *ExplicitTemplateArgs, Deduced, ParamTypes, nullptr, | |||
4104 | Info); | |||
4105 | }); | |||
4106 | if (Result) | |||
4107 | return Result; | |||
4108 | ||||
4109 | NumExplicitlySpecified = Deduced.size(); | |||
4110 | } else { | |||
4111 | // Just fill in the parameter types from the function declaration. | |||
4112 | for (unsigned I = 0; I != NumParams; ++I) | |||
4113 | ParamTypes.push_back(Function->getParamDecl(I)->getType()); | |||
4114 | } | |||
4115 | ||||
4116 | SmallVector<OriginalCallArg, 8> OriginalCallArgs; | |||
4117 | ||||
4118 | // Deduce an argument of type ParamType from an expression with index ArgIdx. | |||
4119 | auto DeduceCallArgument = [&](QualType ParamType, unsigned ArgIdx) { | |||
4120 | // C++ [demp.deduct.call]p1: (DR1391) | |||
4121 | // Template argument deduction is done by comparing each function template | |||
4122 | // parameter that contains template-parameters that participate in | |||
4123 | // template argument deduction ... | |||
4124 | if (!hasDeducibleTemplateParameters(*this, FunctionTemplate, ParamType)) | |||
4125 | return Sema::TDK_Success; | |||
4126 | ||||
4127 | // ... with the type of the corresponding argument | |||
4128 | return DeduceTemplateArgumentsFromCallArgument( | |||
4129 | *this, TemplateParams, FirstInnerIndex, ParamType, Args[ArgIdx], Info, Deduced, | |||
4130 | OriginalCallArgs, /*Decomposed*/false, ArgIdx, /*TDF*/ 0); | |||
4131 | }; | |||
4132 | ||||
4133 | // Deduce template arguments from the function parameters. | |||
4134 | Deduced.resize(TemplateParams->size()); | |||
4135 | SmallVector<QualType, 8> ParamTypesForArgChecking; | |||
4136 | for (unsigned ParamIdx = 0, NumParamTypes = ParamTypes.size(), ArgIdx = 0; | |||
4137 | ParamIdx != NumParamTypes; ++ParamIdx) { | |||
4138 | QualType ParamType = ParamTypes[ParamIdx]; | |||
4139 | ||||
4140 | const PackExpansionType *ParamExpansion = | |||
4141 | dyn_cast<PackExpansionType>(ParamType); | |||
4142 | if (!ParamExpansion) { | |||
4143 | // Simple case: matching a function parameter to a function argument. | |||
4144 | if (ArgIdx >= Args.size()) | |||
4145 | break; | |||
4146 | ||||
4147 | ParamTypesForArgChecking.push_back(ParamType); | |||
4148 | if (auto Result = DeduceCallArgument(ParamType, ArgIdx++)) | |||
4149 | return Result; | |||
4150 | ||||
4151 | continue; | |||
4152 | } | |||
4153 | ||||
4154 | QualType ParamPattern = ParamExpansion->getPattern(); | |||
4155 | PackDeductionScope PackScope(*this, TemplateParams, Deduced, Info, | |||
4156 | ParamPattern); | |||
4157 | ||||
4158 | // C++0x [temp.deduct.call]p1: | |||
4159 | // For a function parameter pack that occurs at the end of the | |||
4160 | // parameter-declaration-list, the type A of each remaining argument of | |||
4161 | // the call is compared with the type P of the declarator-id of the | |||
4162 | // function parameter pack. Each comparison deduces template arguments | |||
4163 | // for subsequent positions in the template parameter packs expanded by | |||
4164 | // the function parameter pack. When a function parameter pack appears | |||
4165 | // in a non-deduced context [not at the end of the list], the type of | |||
4166 | // that parameter pack is never deduced. | |||
4167 | // | |||
4168 | // FIXME: The above rule allows the size of the parameter pack to change | |||
4169 | // after we skip it (in the non-deduced case). That makes no sense, so | |||
4170 | // we instead notionally deduce the pack against N arguments, where N is | |||
4171 | // the length of the explicitly-specified pack if it's expanded by the | |||
4172 | // parameter pack and 0 otherwise, and we treat each deduction as a | |||
4173 | // non-deduced context. | |||
4174 | if (ParamIdx + 1 == NumParamTypes || PackScope.hasFixedArity()) { | |||
4175 | for (; ArgIdx < Args.size() && PackScope.hasNextElement(); | |||
4176 | PackScope.nextPackElement(), ++ArgIdx) { | |||
4177 | ParamTypesForArgChecking.push_back(ParamPattern); | |||
4178 | if (auto Result = DeduceCallArgument(ParamPattern, ArgIdx)) | |||
4179 | return Result; | |||
4180 | } | |||
4181 | } else { | |||
4182 | // If the parameter type contains an explicitly-specified pack that we | |||
4183 | // could not expand, skip the number of parameters notionally created | |||
4184 | // by the expansion. | |||
4185 | Optional<unsigned> NumExpansions = ParamExpansion->getNumExpansions(); | |||
4186 | if (NumExpansions && !PackScope.isPartiallyExpanded()) { | |||
4187 | for (unsigned I = 0; I != *NumExpansions && ArgIdx < Args.size(); | |||
4188 | ++I, ++ArgIdx) { | |||
4189 | ParamTypesForArgChecking.push_back(ParamPattern); | |||
4190 | // FIXME: Should we add OriginalCallArgs for these? What if the | |||
4191 | // corresponding argument is a list? | |||
4192 | PackScope.nextPackElement(); | |||
4193 | } | |||
4194 | } | |||
4195 | } | |||
4196 | ||||
4197 | // Build argument packs for each of the parameter packs expanded by this | |||
4198 | // pack expansion. | |||
4199 | if (auto Result = PackScope.finish()) | |||
4200 | return Result; | |||
4201 | } | |||
4202 | ||||
4203 | // Capture the context in which the function call is made. This is the context | |||
4204 | // that is needed when the accessibility of template arguments is checked. | |||
4205 | DeclContext *CallingCtx = CurContext; | |||
4206 | ||||
4207 | TemplateDeductionResult Result; | |||
4208 | runWithSufficientStackSpace(Info.getLocation(), [&] { | |||
4209 | Result = FinishTemplateArgumentDeduction( | |||
4210 | FunctionTemplate, Deduced, NumExplicitlySpecified, Specialization, Info, | |||
4211 | &OriginalCallArgs, PartialOverloading, [&, CallingCtx]() { | |||
4212 | ContextRAII SavedContext(*this, CallingCtx); | |||
4213 | return CheckNonDependent(ParamTypesForArgChecking); | |||
4214 | }); | |||
4215 | }); | |||
4216 | return Result; | |||
4217 | } | |||
4218 | ||||
4219 | QualType Sema::adjustCCAndNoReturn(QualType ArgFunctionType, | |||
4220 | QualType FunctionType, | |||
4221 | bool AdjustExceptionSpec) { | |||
4222 | if (ArgFunctionType.isNull()) | |||
4223 | return ArgFunctionType; | |||
4224 | ||||
4225 | const auto *FunctionTypeP = FunctionType->castAs<FunctionProtoType>(); | |||
4226 | const auto *ArgFunctionTypeP = ArgFunctionType->castAs<FunctionProtoType>(); | |||
4227 | FunctionProtoType::ExtProtoInfo EPI = ArgFunctionTypeP->getExtProtoInfo(); | |||
4228 | bool Rebuild = false; | |||
4229 | ||||
4230 | CallingConv CC = FunctionTypeP->getCallConv(); | |||
4231 | if (EPI.ExtInfo.getCC() != CC) { | |||
4232 | EPI.ExtInfo = EPI.ExtInfo.withCallingConv(CC); | |||
4233 | Rebuild = true; | |||
4234 | } | |||
4235 | ||||
4236 | bool NoReturn = FunctionTypeP->getNoReturnAttr(); | |||
4237 | if (EPI.ExtInfo.getNoReturn() != NoReturn) { | |||
4238 | EPI.ExtInfo = EPI.ExtInfo.withNoReturn(NoReturn); | |||
4239 | Rebuild = true; | |||
4240 | } | |||
4241 | ||||
4242 | if (AdjustExceptionSpec && (FunctionTypeP->hasExceptionSpec() || | |||
4243 | ArgFunctionTypeP->hasExceptionSpec())) { | |||
4244 | EPI.ExceptionSpec = FunctionTypeP->getExtProtoInfo().ExceptionSpec; | |||
4245 | Rebuild = true; | |||
4246 | } | |||
4247 | ||||
4248 | if (!Rebuild) | |||
4249 | return ArgFunctionType; | |||
4250 | ||||
4251 | return Context.getFunctionType(ArgFunctionTypeP->getReturnType(), | |||
4252 | ArgFunctionTypeP->getParamTypes(), EPI); | |||
4253 | } | |||
4254 | ||||
4255 | /// Deduce template arguments when taking the address of a function | |||
4256 | /// template (C++ [temp.deduct.funcaddr]) or matching a specialization to | |||
4257 | /// a template. | |||
4258 | /// | |||
4259 | /// \param FunctionTemplate the function template for which we are performing | |||
4260 | /// template argument deduction. | |||
4261 | /// | |||
4262 | /// \param ExplicitTemplateArgs the explicitly-specified template | |||
4263 | /// arguments. | |||
4264 | /// | |||
4265 | /// \param ArgFunctionType the function type that will be used as the | |||
4266 | /// "argument" type (A) when performing template argument deduction from the | |||
4267 | /// function template's function type. This type may be NULL, if there is no | |||
4268 | /// argument type to compare against, in C++0x [temp.arg.explicit]p3. | |||
4269 | /// | |||
4270 | /// \param Specialization if template argument deduction was successful, | |||
4271 | /// this will be set to the function template specialization produced by | |||
4272 | /// template argument deduction. | |||
4273 | /// | |||
4274 | /// \param Info the argument will be updated to provide additional information | |||
4275 | /// about template argument deduction. | |||
4276 | /// | |||
4277 | /// \param IsAddressOfFunction If \c true, we are deducing as part of taking | |||
4278 | /// the address of a function template per [temp.deduct.funcaddr] and | |||
4279 | /// [over.over]. If \c false, we are looking up a function template | |||
4280 | /// specialization based on its signature, per [temp.deduct.decl]. | |||
4281 | /// | |||
4282 | /// \returns the result of template argument deduction. | |||
4283 | Sema::TemplateDeductionResult Sema::DeduceTemplateArguments( | |||
4284 | FunctionTemplateDecl *FunctionTemplate, | |||
4285 | TemplateArgumentListInfo *ExplicitTemplateArgs, QualType ArgFunctionType, | |||
4286 | FunctionDecl *&Specialization, TemplateDeductionInfo &Info, | |||
4287 | bool IsAddressOfFunction) { | |||
4288 | if (FunctionTemplate->isInvalidDecl()) | |||
4289 | return TDK_Invalid; | |||
4290 | ||||
4291 | FunctionDecl *Function = FunctionTemplate->getTemplatedDecl(); | |||
4292 | TemplateParameterList *TemplateParams | |||
4293 | = FunctionTemplate->getTemplateParameters(); | |||
4294 | QualType FunctionType = Function->getType(); | |||
4295 | ||||
4296 | // Substitute any explicit template arguments. | |||
4297 | LocalInstantiationScope InstScope(*this); | |||
4298 | SmallVector<DeducedTemplateArgument, 4> Deduced; | |||
4299 | unsigned NumExplicitlySpecified = 0; | |||
4300 | SmallVector<QualType, 4> ParamTypes; | |||
4301 | if (ExplicitTemplateArgs) { | |||
4302 | TemplateDeductionResult Result; | |||
4303 | runWithSufficientStackSpace(Info.getLocation(), [&] { | |||
4304 | Result = SubstituteExplicitTemplateArguments( | |||
4305 | FunctionTemplate, *ExplicitTemplateArgs, Deduced, ParamTypes, | |||
4306 | &FunctionType, Info); | |||
4307 | }); | |||
4308 | if (Result) | |||
4309 | return Result; | |||
4310 | ||||
4311 | NumExplicitlySpecified = Deduced.size(); | |||
4312 | } | |||
4313 | ||||
4314 | // When taking the address of a function, we require convertibility of | |||
4315 | // the resulting function type. Otherwise, we allow arbitrary mismatches | |||
4316 | // of calling convention and noreturn. | |||
4317 | if (!IsAddressOfFunction) | |||
4318 | ArgFunctionType = adjustCCAndNoReturn(ArgFunctionType, FunctionType, | |||
4319 | /*AdjustExceptionSpec*/false); | |||
4320 | ||||
4321 | // Unevaluated SFINAE context. | |||
4322 | EnterExpressionEvaluationContext Unevaluated( | |||
4323 | *this, Sema::ExpressionEvaluationContext::Unevaluated); | |||
4324 | SFINAETrap Trap(*this); | |||
4325 | ||||
4326 | Deduced.resize(TemplateParams->size()); | |||
4327 | ||||
4328 | // If the function has a deduced return type, substitute it for a dependent | |||
4329 | // type so that we treat it as a non-deduced context in what follows. If we | |||
4330 | // are looking up by signature, the signature type should also have a deduced | |||
4331 | // return type, which we instead expect to exactly match. | |||
4332 | bool HasDeducedReturnType = false; | |||
4333 | if (getLangOpts().CPlusPlus14 && IsAddressOfFunction && | |||
4334 | Function->getReturnType()->getContainedAutoType()) { | |||
4335 | FunctionType = SubstAutoType(FunctionType, Context.DependentTy); | |||
4336 | HasDeducedReturnType = true; | |||
4337 | } | |||
4338 | ||||
4339 | if (!ArgFunctionType.isNull()) { | |||
4340 | unsigned TDF = | |||
4341 | TDF_TopLevelParameterTypeList | TDF_AllowCompatibleFunctionType; | |||
4342 | // Deduce template arguments from the function type. | |||
4343 | if (TemplateDeductionResult Result | |||
4344 | = DeduceTemplateArgumentsByTypeMatch(*this, TemplateParams, | |||
4345 | FunctionType, ArgFunctionType, | |||
4346 | Info, Deduced, TDF)) | |||
4347 | return Result; | |||
4348 | } | |||
4349 | ||||
4350 | TemplateDeductionResult Result; | |||
4351 | runWithSufficientStackSpace(Info.getLocation(), [&] { | |||
4352 | Result = FinishTemplateArgumentDeduction(FunctionTemplate, Deduced, | |||
4353 | NumExplicitlySpecified, | |||
4354 | Specialization, Info); | |||
4355 | }); | |||
4356 | if (Result) | |||
4357 | return Result; | |||
4358 | ||||
4359 | // If the function has a deduced return type, deduce it now, so we can check | |||
4360 | // that the deduced function type matches the requested type. | |||
4361 | if (HasDeducedReturnType && | |||
4362 | Specialization->getReturnType()->isUndeducedType() && | |||
4363 | DeduceReturnType(Specialization, Info.getLocation(), false)) | |||
4364 | return TDK_MiscellaneousDeductionFailure; | |||
4365 | ||||
4366 | // If the function has a dependent exception specification, resolve it now, | |||
4367 | // so we can check that the exception specification matches. | |||
4368 | auto *SpecializationFPT = | |||
4369 | Specialization->getType()->castAs<FunctionProtoType>(); | |||
4370 | if (getLangOpts().CPlusPlus17 && | |||
4371 | isUnresolvedExceptionSpec(SpecializationFPT->getExceptionSpecType()) && | |||
4372 | !ResolveExceptionSpec(Info.getLocation(), SpecializationFPT)) | |||
4373 | return TDK_MiscellaneousDeductionFailure; | |||
4374 | ||||
4375 | // Adjust the exception specification of the argument to match the | |||
4376 | // substituted and resolved type we just formed. (Calling convention and | |||
4377 | // noreturn can't be dependent, so we don't actually need this for them | |||
4378 | // right now.) | |||
4379 | QualType SpecializationType = Specialization->getType(); | |||
4380 | if (!IsAddressOfFunction) | |||
4381 | ArgFunctionType = adjustCCAndNoReturn(ArgFunctionType, SpecializationType, | |||
4382 | /*AdjustExceptionSpec*/true); | |||
4383 | ||||
4384 | // If the requested function type does not match the actual type of the | |||
4385 | // specialization with respect to arguments of compatible pointer to function | |||
4386 | // types, template argument deduction fails. | |||
4387 | if (!ArgFunctionType.isNull()) { | |||
4388 | if (IsAddressOfFunction && | |||
4389 | !isSameOrCompatibleFunctionType( | |||
4390 | Context.getCanonicalType(SpecializationType), | |||
4391 | Context.getCanonicalType(ArgFunctionType))) | |||
4392 | return TDK_MiscellaneousDeductionFailure; | |||
4393 | ||||
4394 | if (!IsAddressOfFunction && | |||
4395 | !Context.hasSameType(SpecializationType, ArgFunctionType)) | |||
4396 | return TDK_MiscellaneousDeductionFailure; | |||
4397 | } | |||
4398 | ||||
4399 | return TDK_Success; | |||
4400 | } | |||
4401 | ||||
4402 | /// Deduce template arguments for a templated conversion | |||
4403 | /// function (C++ [temp.deduct.conv]) and, if successful, produce a | |||
4404 | /// conversion function template specialization. | |||
4405 | Sema::TemplateDeductionResult | |||
4406 | Sema::DeduceTemplateArguments(FunctionTemplateDecl *ConversionTemplate, | |||
4407 | QualType ToType, | |||
4408 | CXXConversionDecl *&Specialization, | |||
4409 | TemplateDeductionInfo &Info) { | |||
4410 | if (ConversionTemplate->isInvalidDecl()) | |||
4411 | return TDK_Invalid; | |||
4412 | ||||
4413 | CXXConversionDecl *ConversionGeneric | |||
4414 | = cast<CXXConversionDecl>(ConversionTemplate->getTemplatedDecl()); | |||
4415 | ||||
4416 | QualType FromType = ConversionGeneric->getConversionType(); | |||
4417 | ||||
4418 | // Canonicalize the types for deduction. | |||
4419 | QualType P = Context.getCanonicalType(FromType); | |||
4420 | QualType A = Context.getCanonicalType(ToType); | |||
4421 | ||||
4422 | // C++0x [temp.deduct.conv]p2: | |||
4423 | // If P is a reference type, the type referred to by P is used for | |||
4424 | // type deduction. | |||
4425 | if (const ReferenceType *PRef = P->getAs<ReferenceType>()) | |||
4426 | P = PRef->getPointeeType(); | |||
4427 | ||||
4428 | // C++0x [temp.deduct.conv]p4: | |||
4429 | // [...] If A is a reference type, the type referred to by A is used | |||
4430 | // for type deduction. | |||
4431 | if (const ReferenceType *ARef = A->getAs<ReferenceType>()) { | |||
4432 | A = ARef->getPointeeType(); | |||
4433 | // We work around a defect in the standard here: cv-qualifiers are also | |||
4434 | // removed from P and A in this case, unless P was a reference type. This | |||
4435 | // seems to mostly match what other compilers are doing. | |||
4436 | if (!FromType->getAs<ReferenceType>()) { | |||
4437 | A = A.getUnqualifiedType(); | |||
4438 | P = P.getUnqualifiedType(); | |||
4439 | } | |||
4440 | ||||
4441 | // C++ [temp.deduct.conv]p3: | |||
4442 | // | |||
4443 | // If A is not a reference type: | |||
4444 | } else { | |||
4445 | 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-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 4445, __PRETTY_FUNCTION__)); | |||
4446 | ||||
4447 | // - If P is an array type, the pointer type produced by the | |||
4448 | // array-to-pointer standard conversion (4.2) is used in place | |||
4449 | // of P for type deduction; otherwise, | |||
4450 | if (P->isArrayType()) | |||
4451 | P = Context.getArrayDecayedType(P); | |||
4452 | // - If P is a function type, the pointer type produced by the | |||
4453 | // function-to-pointer standard conversion (4.3) is used in | |||
4454 | // place of P for type deduction; otherwise, | |||
4455 | else if (P->isFunctionType()) | |||
4456 | P = Context.getPointerType(P); | |||
4457 | // - If P is a cv-qualified type, the top level cv-qualifiers of | |||
4458 | // P's type are ignored for type deduction. | |||
4459 | else | |||
4460 | P = P.getUnqualifiedType(); | |||
4461 | ||||
4462 | // C++0x [temp.deduct.conv]p4: | |||
4463 | // If A is a cv-qualified type, the top level cv-qualifiers of A's | |||
4464 | // type are ignored for type deduction. If A is a reference type, the type | |||
4465 | // referred to by A is used for type deduction. | |||
4466 | A = A.getUnqualifiedType(); | |||
4467 | } | |||
4468 | ||||
4469 | // Unevaluated SFINAE context. | |||
4470 | EnterExpressionEvaluationContext Unevaluated( | |||
4471 | *this, Sema::ExpressionEvaluationContext::Unevaluated); | |||
4472 | SFINAETrap Trap(*this); | |||
4473 | ||||
4474 | // C++ [temp.deduct.conv]p1: | |||
4475 | // Template argument deduction is done by comparing the return | |||
4476 | // type of the template conversion function (call it P) with the | |||
4477 | // type that is required as the result of the conversion (call it | |||
4478 | // A) as described in 14.8.2.4. | |||
4479 | TemplateParameterList *TemplateParams | |||
4480 | = ConversionTemplate->getTemplateParameters(); | |||
4481 | SmallVector<DeducedTemplateArgument, 4> Deduced; | |||
4482 | Deduced.resize(TemplateParams->size()); | |||
4483 | ||||
4484 | // C++0x [temp.deduct.conv]p4: | |||
4485 | // In general, the deduction process attempts to find template | |||
4486 | // argument values that will make the deduced A identical to | |||
4487 | // A. However, there are two cases that allow a difference: | |||
4488 | unsigned TDF = 0; | |||
4489 | // - If the original A is a reference type, A can be more | |||
4490 | // cv-qualified than the deduced A (i.e., the type referred to | |||
4491 | // by the reference) | |||
4492 | if (ToType->isReferenceType()) | |||
4493 | TDF |= TDF_ArgWithReferenceType; | |||
4494 | // - The deduced A can be another pointer or pointer to member | |||
4495 | // type that can be converted to A via a qualification | |||
4496 | // conversion. | |||
4497 | // | |||
4498 | // (C++0x [temp.deduct.conv]p6 clarifies that this only happens when | |||
4499 | // both P and A are pointers or member pointers. In this case, we | |||
4500 | // just ignore cv-qualifiers completely). | |||
4501 | if ((P->isPointerType() && A->isPointerType()) || | |||
4502 | (P->isMemberPointerType() && A->isMemberPointerType())) | |||
4503 | TDF |= TDF_IgnoreQualifiers; | |||
4504 | if (TemplateDeductionResult Result | |||
4505 | = DeduceTemplateArgumentsByTypeMatch(*this, TemplateParams, | |||
4506 | P, A, Info, Deduced, TDF)) | |||
4507 | return Result; | |||
4508 | ||||
4509 | // Create an Instantiation Scope for finalizing the operator. | |||
4510 | LocalInstantiationScope InstScope(*this); | |||
4511 | // Finish template argument deduction. | |||
4512 | FunctionDecl *ConversionSpecialized = nullptr; | |||
4513 | TemplateDeductionResult Result; | |||
4514 | runWithSufficientStackSpace(Info.getLocation(), [&] { | |||
4515 | Result = FinishTemplateArgumentDeduction(ConversionTemplate, Deduced, 0, | |||
4516 | ConversionSpecialized, Info); | |||
4517 | }); | |||
4518 | Specialization = cast_or_null<CXXConversionDecl>(ConversionSpecialized); | |||
4519 | return Result; | |||
4520 | } | |||
4521 | ||||
4522 | /// Deduce template arguments for a function template when there is | |||
4523 | /// nothing to deduce against (C++0x [temp.arg.explicit]p3). | |||
4524 | /// | |||
4525 | /// \param FunctionTemplate the function template for which we are performing | |||
4526 | /// template argument deduction. | |||
4527 | /// | |||
4528 | /// \param ExplicitTemplateArgs the explicitly-specified template | |||
4529 | /// arguments. | |||
4530 | /// | |||
4531 | /// \param Specialization if template argument deduction was successful, | |||
4532 | /// this will be set to the function template specialization produced by | |||
4533 | /// template argument deduction. | |||
4534 | /// | |||
4535 | /// \param Info the argument will be updated to provide additional information | |||
4536 | /// about template argument deduction. | |||
4537 | /// | |||
4538 | /// \param IsAddressOfFunction If \c true, we are deducing as part of taking | |||
4539 | /// the address of a function template in a context where we do not have a | |||
4540 | /// target type, per [over.over]. If \c false, we are looking up a function | |||
4541 | /// template specialization based on its signature, which only happens when | |||
4542 | /// deducing a function parameter type from an argument that is a template-id | |||
4543 | /// naming a function template specialization. | |||
4544 | /// | |||
4545 | /// \returns the result of template argument deduction. | |||
4546 | Sema::TemplateDeductionResult Sema::DeduceTemplateArguments( | |||
4547 | FunctionTemplateDecl *FunctionTemplate, | |||
4548 | TemplateArgumentListInfo *ExplicitTemplateArgs, | |||
4549 | FunctionDecl *&Specialization, TemplateDeductionInfo &Info, | |||
4550 | bool IsAddressOfFunction) { | |||
4551 | return DeduceTemplateArguments(FunctionTemplate, ExplicitTemplateArgs, | |||
4552 | QualType(), Specialization, Info, | |||
4553 | IsAddressOfFunction); | |||
4554 | } | |||
4555 | ||||
4556 | namespace { | |||
4557 | struct DependentAuto { bool IsPack; }; | |||
4558 | ||||
4559 | /// Substitute the 'auto' specifier or deduced template specialization type | |||
4560 | /// specifier within a type for a given replacement type. | |||
4561 | class SubstituteDeducedTypeTransform : | |||
4562 | public TreeTransform<SubstituteDeducedTypeTransform> { | |||
4563 | QualType Replacement; | |||
4564 | bool ReplacementIsPack; | |||
4565 | bool UseTypeSugar; | |||
4566 | ||||
4567 | public: | |||
4568 | SubstituteDeducedTypeTransform(Sema &SemaRef, DependentAuto DA) | |||
4569 | : TreeTransform<SubstituteDeducedTypeTransform>(SemaRef), Replacement(), | |||
4570 | ReplacementIsPack(DA.IsPack), UseTypeSugar(true) {} | |||
4571 | ||||
4572 | SubstituteDeducedTypeTransform(Sema &SemaRef, QualType Replacement, | |||
4573 | bool UseTypeSugar = true) | |||
4574 | : TreeTransform<SubstituteDeducedTypeTransform>(SemaRef), | |||
4575 | Replacement(Replacement), ReplacementIsPack(false), | |||
4576 | UseTypeSugar(UseTypeSugar) {} | |||
4577 | ||||
4578 | QualType TransformDesugared(TypeLocBuilder &TLB, DeducedTypeLoc TL) { | |||
4579 | 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-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 4580, __PRETTY_FUNCTION__)) | |||
4580 | "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-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 4580, __PRETTY_FUNCTION__)); | |||
4581 | QualType Result = Replacement; | |||
4582 | TemplateTypeParmTypeLoc NewTL = TLB.push<TemplateTypeParmTypeLoc>(Result); | |||
4583 | NewTL.setNameLoc(TL.getNameLoc()); | |||
4584 | return Result; | |||
4585 | } | |||
4586 | ||||
4587 | QualType TransformAutoType(TypeLocBuilder &TLB, AutoTypeLoc TL) { | |||
4588 | // If we're building the type pattern to deduce against, don't wrap the | |||
4589 | // substituted type in an AutoType. Certain template deduction rules | |||
4590 | // apply only when a template type parameter appears directly (and not if | |||
4591 | // the parameter is found through desugaring). For instance: | |||
4592 | // auto &&lref = lvalue; | |||
4593 | // must transform into "rvalue reference to T" not "rvalue reference to | |||
4594 | // auto type deduced as T" in order for [temp.deduct.call]p3 to apply. | |||
4595 | // | |||
4596 | // FIXME: Is this still necessary? | |||
4597 | if (!UseTypeSugar) | |||
4598 | return TransformDesugared(TLB, TL); | |||
4599 | ||||
4600 | QualType Result = SemaRef.Context.getAutoType( | |||
4601 | Replacement, TL.getTypePtr()->getKeyword(), Replacement.isNull(), | |||
4602 | ReplacementIsPack, TL.getTypePtr()->getTypeConstraintConcept(), | |||
4603 | TL.getTypePtr()->getTypeConstraintArguments()); | |||
4604 | auto NewTL = TLB.push<AutoTypeLoc>(Result); | |||
4605 | NewTL.copy(TL); | |||
4606 | return Result; | |||
4607 | } | |||
4608 | ||||
4609 | QualType TransformDeducedTemplateSpecializationType( | |||
4610 | TypeLocBuilder &TLB, DeducedTemplateSpecializationTypeLoc TL) { | |||
4611 | if (!UseTypeSugar) | |||
4612 | return TransformDesugared(TLB, TL); | |||
4613 | ||||
4614 | QualType Result = SemaRef.Context.getDeducedTemplateSpecializationType( | |||
4615 | TL.getTypePtr()->getTemplateName(), | |||
4616 | Replacement, Replacement.isNull()); | |||
4617 | auto NewTL = TLB.push<DeducedTemplateSpecializationTypeLoc>(Result); | |||
4618 | NewTL.setNameLoc(TL.getNameLoc()); | |||
4619 | return Result; | |||
4620 | } | |||
4621 | ||||
4622 | ExprResult TransformLambdaExpr(LambdaExpr *E) { | |||
4623 | // Lambdas never need to be transformed. | |||
4624 | return E; | |||
4625 | } | |||
4626 | ||||
4627 | QualType Apply(TypeLoc TL) { | |||
4628 | // Create some scratch storage for the transformed type locations. | |||
4629 | // FIXME: We're just going to throw this information away. Don't build it. | |||
4630 | TypeLocBuilder TLB; | |||
4631 | TLB.reserve(TL.getFullDataSize()); | |||
4632 | return TransformType(TLB, TL); | |||
4633 | } | |||
4634 | }; | |||
4635 | ||||
4636 | } // namespace | |||
4637 | ||||
4638 | Sema::DeduceAutoResult | |||
4639 | Sema::DeduceAutoType(TypeSourceInfo *Type, Expr *&Init, QualType &Result, | |||
4640 | Optional<unsigned> DependentDeductionDepth, | |||
4641 | bool IgnoreConstraints) { | |||
4642 | return DeduceAutoType(Type->getTypeLoc(), Init, Result, | |||
4643 | DependentDeductionDepth, IgnoreConstraints); | |||
4644 | } | |||
4645 | ||||
4646 | /// Attempt to produce an informative diagostic explaining why auto deduction | |||
4647 | /// failed. | |||
4648 | /// \return \c true if diagnosed, \c false if not. | |||
4649 | static bool diagnoseAutoDeductionFailure(Sema &S, | |||
4650 | Sema::TemplateDeductionResult TDK, | |||
4651 | TemplateDeductionInfo &Info, | |||
4652 | ArrayRef<SourceRange> Ranges) { | |||
4653 | switch (TDK) { | |||
4654 | case Sema::TDK_Inconsistent: { | |||
4655 | // Inconsistent deduction means we were deducing from an initializer list. | |||
4656 | auto D = S.Diag(Info.getLocation(), diag::err_auto_inconsistent_deduction); | |||
4657 | D << Info.FirstArg << Info.SecondArg; | |||
4658 | for (auto R : Ranges) | |||
4659 | D << R; | |||
4660 | return true; | |||
4661 | } | |||
4662 | ||||
4663 | // FIXME: Are there other cases for which a custom diagnostic is more useful | |||
4664 | // than the basic "types don't match" diagnostic? | |||
4665 | ||||
4666 | default: | |||
4667 | return false; | |||
4668 | } | |||
4669 | } | |||
4670 | ||||
4671 | static Sema::DeduceAutoResult | |||
4672 | CheckDeducedPlaceholderConstraints(Sema &S, const AutoType &Type, | |||
4673 | AutoTypeLoc TypeLoc, QualType Deduced) { | |||
4674 | ConstraintSatisfaction Satisfaction; | |||
4675 | ConceptDecl *Concept = Type.getTypeConstraintConcept(); | |||
4676 | TemplateArgumentListInfo TemplateArgs(TypeLoc.getLAngleLoc(), | |||
4677 | TypeLoc.getRAngleLoc()); | |||
4678 | TemplateArgs.addArgument( | |||
4679 | TemplateArgumentLoc(TemplateArgument(Deduced), | |||
4680 | S.Context.getTrivialTypeSourceInfo( | |||
4681 | Deduced, TypeLoc.getNameLoc()))); | |||
4682 | for (unsigned I = 0, C = TypeLoc.getNumArgs(); I != C; ++I) | |||
4683 | TemplateArgs.addArgument(TypeLoc.getArgLoc(I)); | |||
4684 | ||||
4685 | llvm::SmallVector<TemplateArgument, 4> Converted; | |||
4686 | if (S.CheckTemplateArgumentList(Concept, SourceLocation(), TemplateArgs, | |||
4687 | /*PartialTemplateArgs=*/false, Converted)) | |||
4688 | return Sema::DAR_FailedAlreadyDiagnosed; | |||
4689 | if (S.CheckConstraintSatisfaction(Concept, {Concept->getConstraintExpr()}, | |||
4690 | Converted, TypeLoc.getLocalSourceRange(), | |||
4691 | Satisfaction)) | |||
4692 | return Sema::DAR_FailedAlreadyDiagnosed; | |||
4693 | if (!Satisfaction.IsSatisfied) { | |||
4694 | std::string Buf; | |||
4695 | llvm::raw_string_ostream OS(Buf); | |||
4696 | OS << "'" << Concept->getName(); | |||
4697 | if (TypeLoc.hasExplicitTemplateArgs()) { | |||
4698 | OS << "<"; | |||
4699 | for (const auto &Arg : Type.getTypeConstraintArguments()) | |||
4700 | Arg.print(S.getPrintingPolicy(), OS); | |||
4701 | OS << ">"; | |||
4702 | } | |||
4703 | OS << "'"; | |||
4704 | OS.flush(); | |||
4705 | S.Diag(TypeLoc.getConceptNameLoc(), | |||
4706 | diag::err_placeholder_constraints_not_satisfied) | |||
4707 | << Deduced << Buf << TypeLoc.getLocalSourceRange(); | |||
4708 | S.DiagnoseUnsatisfiedConstraint(Satisfaction); | |||
4709 | return Sema::DAR_FailedAlreadyDiagnosed; | |||
4710 | } | |||
4711 | return Sema::DAR_Succeeded; | |||
4712 | } | |||
4713 | ||||
4714 | /// Deduce the type for an auto type-specifier (C++11 [dcl.spec.auto]p6) | |||
4715 | /// | |||
4716 | /// Note that this is done even if the initializer is dependent. (This is | |||
4717 | /// necessary to support partial ordering of templates using 'auto'.) | |||
4718 | /// A dependent type will be produced when deducing from a dependent type. | |||
4719 | /// | |||
4720 | /// \param Type the type pattern using the auto type-specifier. | |||
4721 | /// \param Init the initializer for the variable whose type is to be deduced. | |||
4722 | /// \param Result if type deduction was successful, this will be set to the | |||
4723 | /// deduced type. | |||
4724 | /// \param DependentDeductionDepth Set if we should permit deduction in | |||
4725 | /// dependent cases. This is necessary for template partial ordering with | |||
4726 | /// 'auto' template parameters. The value specified is the template | |||
4727 | /// parameter depth at which we should perform 'auto' deduction. | |||
4728 | /// \param IgnoreConstraints Set if we should not fail if the deduced type does | |||
4729 | /// not satisfy the type-constraint in the auto type. | |||
4730 | Sema::DeduceAutoResult | |||
4731 | Sema::DeduceAutoType(TypeLoc Type, Expr *&Init, QualType &Result, | |||
4732 | Optional<unsigned> DependentDeductionDepth, | |||
4733 | bool IgnoreConstraints) { | |||
4734 | if (Init->containsErrors()) | |||
4735 | return DAR_FailedAlreadyDiagnosed; | |||
4736 | if (Init->getType()->isNonOverloadPlaceholderType()) { | |||
4737 | ExprResult NonPlaceholder = CheckPlaceholderExpr(Init); | |||
4738 | if (NonPlaceholder.isInvalid()) | |||
4739 | return DAR_FailedAlreadyDiagnosed; | |||
4740 | Init = NonPlaceholder.get(); | |||
4741 | } | |||
4742 | ||||
4743 | DependentAuto DependentResult = { | |||
4744 | /*.IsPack = */ (bool)Type.getAs<PackExpansionTypeLoc>()}; | |||
4745 | ||||
4746 | if (!DependentDeductionDepth && | |||
4747 | (Type.getType()->isDependentType() || Init->isTypeDependent() || | |||
4748 | Init->containsUnexpandedParameterPack())) { | |||
4749 | Result = SubstituteDeducedTypeTransform(*this, DependentResult).Apply(Type); | |||
4750 | 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-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 4750, __PRETTY_FUNCTION__)); | |||
4751 | return DAR_Succeeded; | |||
4752 | } | |||
4753 | ||||
4754 | // Find the depth of template parameter to synthesize. | |||
4755 | unsigned Depth = DependentDeductionDepth.getValueOr(0); | |||
4756 | ||||
4757 | // If this is a 'decltype(auto)' specifier, do the decltype dance. | |||
4758 | // Since 'decltype(auto)' can only occur at the top of the type, we | |||
4759 | // don't need to go digging for it. | |||
4760 | if (const AutoType *AT = Type.getType()->getAs<AutoType>()) { | |||
4761 | if (AT->isDecltypeAuto()) { | |||
4762 | if (isa<InitListExpr>(Init)) { | |||
4763 | Diag(Init->getBeginLoc(), diag::err_decltype_auto_initializer_list); | |||
4764 | return DAR_FailedAlreadyDiagnosed; | |||
4765 | } | |||
4766 | ||||
4767 | ExprResult ER = CheckPlaceholderExpr(Init); | |||
4768 | if (ER.isInvalid()) | |||
4769 | return DAR_FailedAlreadyDiagnosed; | |||
4770 | Init = ER.get(); | |||
4771 | QualType Deduced = BuildDecltypeType(Init, Init->getBeginLoc(), false); | |||
4772 | if (Deduced.isNull()) | |||
4773 | return DAR_FailedAlreadyDiagnosed; | |||
4774 | // FIXME: Support a non-canonical deduced type for 'auto'. | |||
4775 | Deduced = Context.getCanonicalType(Deduced); | |||
4776 | if (AT->isConstrained() && !IgnoreConstraints) { | |||
4777 | auto ConstraintsResult = | |||
4778 | CheckDeducedPlaceholderConstraints(*this, *AT, | |||
4779 | Type.getContainedAutoTypeLoc(), | |||
4780 | Deduced); | |||
4781 | if (ConstraintsResult != DAR_Succeeded) | |||
4782 | return ConstraintsResult; | |||
4783 | } | |||
4784 | Result = SubstituteDeducedTypeTransform(*this, Deduced).Apply(Type); | |||
4785 | if (Result.isNull()) | |||
4786 | return DAR_FailedAlreadyDiagnosed; | |||
4787 | return DAR_Succeeded; | |||
4788 | } else if (!getLangOpts().CPlusPlus) { | |||
4789 | if (isa<InitListExpr>(Init)) { | |||
4790 | Diag(Init->getBeginLoc(), diag::err_auto_init_list_from_c); | |||
4791 | return DAR_FailedAlreadyDiagnosed; | |||
4792 | } | |||
4793 | } | |||
4794 | } | |||
4795 | ||||
4796 | SourceLocation Loc = Init->getExprLoc(); | |||
4797 | ||||
4798 | LocalInstantiationScope InstScope(*this); | |||
4799 | ||||
4800 | // Build template<class TemplParam> void Func(FuncParam); | |||
4801 | TemplateTypeParmDecl *TemplParam = TemplateTypeParmDecl::Create( | |||
4802 | Context, nullptr, SourceLocation(), Loc, Depth, 0, nullptr, false, false, | |||
4803 | false); | |||
4804 | QualType TemplArg = QualType(TemplParam->getTypeForDecl(), 0); | |||
4805 | NamedDecl *TemplParamPtr = TemplParam; | |||
4806 | FixedSizeTemplateParameterListStorage<1, false> TemplateParamsSt( | |||
4807 | Context, Loc, Loc, TemplParamPtr, Loc, nullptr); | |||
4808 | ||||
4809 | QualType FuncParam = | |||
4810 | SubstituteDeducedTypeTransform(*this, TemplArg, /*UseTypeSugar*/false) | |||
4811 | .Apply(Type); | |||
4812 | 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-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 4813, __PRETTY_FUNCTION__)) | |||
4813 | "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-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 4813, __PRETTY_FUNCTION__)); | |||
4814 | ||||
4815 | // Deduce type of TemplParam in Func(Init) | |||
4816 | SmallVector<DeducedTemplateArgument, 1> Deduced; | |||
4817 | Deduced.resize(1); | |||
4818 | ||||
4819 | TemplateDeductionInfo Info(Loc, Depth); | |||
4820 | ||||
4821 | // If deduction failed, don't diagnose if the initializer is dependent; it | |||
4822 | // might acquire a matching type in the instantiation. | |||
4823 | auto DeductionFailed = [&](TemplateDeductionResult TDK, | |||
4824 | ArrayRef<SourceRange> Ranges) -> DeduceAutoResult { | |||
4825 | if (Init->isTypeDependent()) { | |||
4826 | Result = | |||
4827 | SubstituteDeducedTypeTransform(*this, DependentResult).Apply(Type); | |||
4828 | 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-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 4828, __PRETTY_FUNCTION__)); | |||
4829 | return DAR_Succeeded; | |||
4830 | } | |||
4831 | if (diagnoseAutoDeductionFailure(*this, TDK, Info, Ranges)) | |||
4832 | return DAR_FailedAlreadyDiagnosed; | |||
4833 | return DAR_Failed; | |||
4834 | }; | |||
4835 | ||||
4836 | SmallVector<OriginalCallArg, 4> OriginalCallArgs; | |||
4837 | ||||
4838 | InitListExpr *InitList = dyn_cast<InitListExpr>(Init); | |||
4839 | if (InitList) { | |||
4840 | // Notionally, we substitute std::initializer_list<T> for 'auto' and deduce | |||
4841 | // against that. Such deduction only succeeds if removing cv-qualifiers and | |||
4842 | // references results in std::initializer_list<T>. | |||
4843 | if (!Type.getType().getNonReferenceType()->getAs<AutoType>()) | |||
4844 | return DAR_Failed; | |||
4845 | ||||
4846 | // Resolving a core issue: a braced-init-list containing any designators is | |||
4847 | // a non-deduced context. | |||
4848 | for (Expr *E : InitList->inits()) | |||
4849 | if (isa<DesignatedInitExpr>(E)) | |||
4850 | return DAR_Failed; | |||
4851 | ||||
4852 | SourceRange DeducedFromInitRange; | |||
4853 | for (unsigned i = 0, e = InitList->getNumInits(); i < e; ++i) { | |||
4854 | Expr *Init = InitList->getInit(i); | |||
4855 | ||||
4856 | if (auto TDK = DeduceTemplateArgumentsFromCallArgument( | |||
4857 | *this, TemplateParamsSt.get(), 0, TemplArg, Init, | |||
4858 | Info, Deduced, OriginalCallArgs, /*Decomposed*/ true, | |||
4859 | /*ArgIdx*/ 0, /*TDF*/ 0)) | |||
4860 | return DeductionFailed(TDK, {DeducedFromInitRange, | |||
4861 | Init->getSourceRange()}); | |||
4862 | ||||
4863 | if (DeducedFromInitRange.isInvalid() && | |||
4864 | Deduced[0].getKind() != TemplateArgument::Null) | |||
4865 | DeducedFromInitRange = Init->getSourceRange(); | |||
4866 | } | |||
4867 | } else { | |||
4868 | if (!getLangOpts().CPlusPlus && Init->refersToBitField()) { | |||
4869 | Diag(Loc, diag::err_auto_bitfield); | |||
4870 | return DAR_FailedAlreadyDiagnosed; | |||
4871 | } | |||
4872 | ||||
4873 | if (auto TDK = DeduceTemplateArgumentsFromCallArgument( | |||
4874 | *this, TemplateParamsSt.get(), 0, FuncParam, Init, Info, Deduced, | |||
4875 | OriginalCallArgs, /*Decomposed*/ false, /*ArgIdx*/ 0, /*TDF*/ 0)) | |||
4876 | return DeductionFailed(TDK, {}); | |||
4877 | } | |||
4878 | ||||
4879 | // Could be null if somehow 'auto' appears in a non-deduced context. | |||
4880 | if (Deduced[0].getKind() != TemplateArgument::Type) | |||
4881 | return DeductionFailed(TDK_Incomplete, {}); | |||
4882 | ||||
4883 | QualType DeducedType = Deduced[0].getAsType(); | |||
4884 | ||||
4885 | if (InitList) { | |||
4886 | DeducedType = BuildStdInitializerList(DeducedType, Loc); | |||
4887 | if (DeducedType.isNull()) | |||
4888 | return DAR_FailedAlreadyDiagnosed; | |||
4889 | } | |||
4890 | ||||
4891 | if (const auto *AT = Type.getType()->getAs<AutoType>()) { | |||
4892 | if (AT->isConstrained() && !IgnoreConstraints) { | |||
4893 | auto ConstraintsResult = | |||
4894 | CheckDeducedPlaceholderConstraints(*this, *AT, | |||
4895 | Type.getContainedAutoTypeLoc(), | |||
4896 | DeducedType); | |||
4897 | if (ConstraintsResult != DAR_Succeeded) | |||
4898 | return ConstraintsResult; | |||
4899 | } | |||
4900 | } | |||
4901 | ||||
4902 | Result = SubstituteDeducedTypeTransform(*this, DeducedType).Apply(Type); | |||
4903 | if (Result.isNull()) | |||
4904 | return DAR_FailedAlreadyDiagnosed; | |||
4905 | ||||
4906 | // Check that the deduced argument type is compatible with the original | |||
4907 | // argument type per C++ [temp.deduct.call]p4. | |||
4908 | QualType DeducedA = InitList ? Deduced[0].getAsType() : Result; | |||
4909 | for (const OriginalCallArg &OriginalArg : OriginalCallArgs) { | |||
4910 | 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-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 4911, __PRETTY_FUNCTION__)) | |||
4911 | "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-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 4911, __PRETTY_FUNCTION__)); | |||
4912 | if (auto TDK = | |||
4913 | CheckOriginalCallArgDeduction(*this, Info, OriginalArg, DeducedA)) { | |||
4914 | Result = QualType(); | |||
4915 | return DeductionFailed(TDK, {}); | |||
4916 | } | |||
4917 | } | |||
4918 | ||||
4919 | return DAR_Succeeded; | |||
4920 | } | |||
4921 | ||||
4922 | QualType Sema::SubstAutoType(QualType TypeWithAuto, | |||
4923 | QualType TypeToReplaceAuto) { | |||
4924 | if (TypeToReplaceAuto->isDependentType()) | |||
4925 | return SubstituteDeducedTypeTransform( | |||
4926 | *this, DependentAuto{ | |||
4927 | TypeToReplaceAuto->containsUnexpandedParameterPack()}) | |||
4928 | .TransformType(TypeWithAuto); | |||
4929 | return SubstituteDeducedTypeTransform(*this, TypeToReplaceAuto) | |||
4930 | .TransformType(TypeWithAuto); | |||
4931 | } | |||
4932 | ||||
4933 | TypeSourceInfo *Sema::SubstAutoTypeSourceInfo(TypeSourceInfo *TypeWithAuto, | |||
4934 | QualType TypeToReplaceAuto) { | |||
4935 | if (TypeToReplaceAuto->isDependentType()) | |||
4936 | return SubstituteDeducedTypeTransform( | |||
4937 | *this, | |||
4938 | DependentAuto{ | |||
4939 | TypeToReplaceAuto->containsUnexpandedParameterPack()}) | |||
4940 | .TransformType(TypeWithAuto); | |||
4941 | return SubstituteDeducedTypeTransform(*this, TypeToReplaceAuto) | |||
4942 | .TransformType(TypeWithAuto); | |||
4943 | } | |||
4944 | ||||
4945 | QualType Sema::ReplaceAutoType(QualType TypeWithAuto, | |||
4946 | QualType TypeToReplaceAuto) { | |||
4947 | return SubstituteDeducedTypeTransform(*this, TypeToReplaceAuto, | |||
4948 | /*UseTypeSugar*/ false) | |||
4949 | .TransformType(TypeWithAuto); | |||
4950 | } | |||
4951 | ||||
4952 | TypeSourceInfo *Sema::ReplaceAutoTypeSourceInfo(TypeSourceInfo *TypeWithAuto, | |||
4953 | QualType TypeToReplaceAuto) { | |||
4954 | return SubstituteDeducedTypeTransform(*this, TypeToReplaceAuto, | |||
4955 | /*UseTypeSugar*/ false) | |||
4956 | .TransformType(TypeWithAuto); | |||
4957 | } | |||
4958 | ||||
4959 | void Sema::DiagnoseAutoDeductionFailure(VarDecl *VDecl, Expr *Init) { | |||
4960 | if (isa<InitListExpr>(Init)) | |||
4961 | Diag(VDecl->getLocation(), | |||
4962 | VDecl->isInitCapture() | |||
4963 | ? diag::err_init_capture_deduction_failure_from_init_list | |||
4964 | : diag::err_auto_var_deduction_failure_from_init_list) | |||
4965 | << VDecl->getDeclName() << VDecl->getType() << Init->getSourceRange(); | |||
4966 | else | |||
4967 | Diag(VDecl->getLocation(), | |||
4968 | VDecl->isInitCapture() ? diag::err_init_capture_deduction_failure | |||
4969 | : diag::err_auto_var_deduction_failure) | |||
4970 | << VDecl->getDeclName() << VDecl->getType() << Init->getType() | |||
4971 | << Init->getSourceRange(); | |||
4972 | } | |||
4973 | ||||
4974 | bool Sema::DeduceReturnType(FunctionDecl *FD, SourceLocation Loc, | |||
4975 | bool Diagnose) { | |||
4976 | assert(FD->getReturnType()->isUndeducedType())((FD->getReturnType()->isUndeducedType()) ? static_cast <void> (0) : __assert_fail ("FD->getReturnType()->isUndeducedType()" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 4976, __PRETTY_FUNCTION__)); | |||
4977 | ||||
4978 | // For a lambda's conversion operator, deduce any 'auto' or 'decltype(auto)' | |||
4979 | // within the return type from the call operator's type. | |||
4980 | if (isLambdaConversionOperator(FD)) { | |||
4981 | CXXRecordDecl *Lambda = cast<CXXMethodDecl>(FD)->getParent(); | |||
4982 | FunctionDecl *CallOp = Lambda->getLambdaCallOperator(); | |||
4983 | ||||
4984 | // For a generic lambda, instantiate the call operator if needed. | |||
4985 | if (auto *Args = FD->getTemplateSpecializationArgs()) { | |||
4986 | CallOp = InstantiateFunctionDeclaration( | |||
4987 | CallOp->getDescribedFunctionTemplate(), Args, Loc); | |||
4988 | if (!CallOp || CallOp->isInvalidDecl()) | |||
4989 | return true; | |||
4990 | ||||
4991 | // We might need to deduce the return type by instantiating the definition | |||
4992 | // of the operator() function. | |||
4993 | if (CallOp->getReturnType()->isUndeducedType()) { | |||
4994 | runWithSufficientStackSpace(Loc, [&] { | |||
4995 | InstantiateFunctionDefinition(Loc, CallOp); | |||
4996 | }); | |||
4997 | } | |||
4998 | } | |||
4999 | ||||
5000 | if (CallOp->isInvalidDecl()) | |||
5001 | return true; | |||
5002 | 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-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 5003, __PRETTY_FUNCTION__)) | |||
5003 | "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-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 5003, __PRETTY_FUNCTION__)); | |||
5004 | ||||
5005 | // Build the new return type from scratch. | |||
5006 | CallingConv RetTyCC = FD->getReturnType() | |||
5007 | ->getPointeeType() | |||
5008 | ->castAs<FunctionType>() | |||
5009 | ->getCallConv(); | |||
5010 | QualType RetType = getLambdaConversionFunctionResultType( | |||
5011 | CallOp->getType()->castAs<FunctionProtoType>(), RetTyCC); | |||
5012 | if (FD->getReturnType()->getAs<PointerType>()) | |||
5013 | RetType = Context.getPointerType(RetType); | |||
5014 | else { | |||
5015 | assert(FD->getReturnType()->getAs<BlockPointerType>())((FD->getReturnType()->getAs<BlockPointerType>()) ? static_cast<void> (0) : __assert_fail ("FD->getReturnType()->getAs<BlockPointerType>()" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 5015, __PRETTY_FUNCTION__)); | |||
5016 | RetType = Context.getBlockPointerType(RetType); | |||
5017 | } | |||
5018 | Context.adjustDeducedFunctionResultType(FD, RetType); | |||
5019 | return false; | |||
5020 | } | |||
5021 | ||||
5022 | if (FD->getTemplateInstantiationPattern()) { | |||
5023 | runWithSufficientStackSpace(Loc, [&] { | |||
5024 | InstantiateFunctionDefinition(Loc, FD); | |||
5025 | }); | |||
5026 | } | |||
5027 | ||||
5028 | bool StillUndeduced = FD->getReturnType()->isUndeducedType(); | |||
5029 | if (StillUndeduced && Diagnose && !FD->isInvalidDecl()) { | |||
5030 | Diag(Loc, diag::err_auto_fn_used_before_defined) << FD; | |||
5031 | Diag(FD->getLocation(), diag::note_callee_decl) << FD; | |||
5032 | } | |||
5033 | ||||
5034 | return StillUndeduced; | |||
5035 | } | |||
5036 | ||||
5037 | /// If this is a non-static member function, | |||
5038 | static void | |||
5039 | AddImplicitObjectParameterType(ASTContext &Context, | |||
5040 | CXXMethodDecl *Method, | |||
5041 | SmallVectorImpl<QualType> &ArgTypes) { | |||
5042 | // C++11 [temp.func.order]p3: | |||
5043 | // [...] The new parameter is of type "reference to cv A," where cv are | |||
5044 | // the cv-qualifiers of the function template (if any) and A is | |||
5045 | // the class of which the function template is a member. | |||
5046 | // | |||
5047 | // The standard doesn't say explicitly, but we pick the appropriate kind of | |||
5048 | // reference type based on [over.match.funcs]p4. | |||
5049 | QualType ArgTy = Context.getTypeDeclType(Method->getParent()); | |||
5050 | ArgTy = Context.getQualifiedType(ArgTy, Method->getMethodQualifiers()); | |||
5051 | if (Method->getRefQualifier() == RQ_RValue) | |||
5052 | ArgTy = Context.getRValueReferenceType(ArgTy); | |||
5053 | else | |||
5054 | ArgTy = Context.getLValueReferenceType(ArgTy); | |||
5055 | ArgTypes.push_back(ArgTy); | |||
5056 | } | |||
5057 | ||||
5058 | /// Determine whether the function template \p FT1 is at least as | |||
5059 | /// specialized as \p FT2. | |||
5060 | static bool isAtLeastAsSpecializedAs(Sema &S, | |||
5061 | SourceLocation Loc, | |||
5062 | FunctionTemplateDecl *FT1, | |||
5063 | FunctionTemplateDecl *FT2, | |||
5064 | TemplatePartialOrderingContext TPOC, | |||
5065 | unsigned NumCallArguments1, | |||
5066 | bool Reversed) { | |||
5067 | assert(!Reversed || TPOC == TPOC_Call)((!Reversed || TPOC == TPOC_Call) ? static_cast<void> ( 0) : __assert_fail ("!Reversed || TPOC == TPOC_Call", "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 5067, __PRETTY_FUNCTION__)); | |||
5068 | ||||
5069 | FunctionDecl *FD1 = FT1->getTemplatedDecl(); | |||
5070 | FunctionDecl *FD2 = FT2->getTemplatedDecl(); | |||
5071 | const FunctionProtoType *Proto1 = FD1->getType()->getAs<FunctionProtoType>(); | |||
5072 | const FunctionProtoType *Proto2 = FD2->getType()->getAs<FunctionProtoType>(); | |||
5073 | ||||
5074 | 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-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 5074, __PRETTY_FUNCTION__)); | |||
5075 | TemplateParameterList *TemplateParams = FT2->getTemplateParameters(); | |||
5076 | SmallVector<DeducedTemplateArgument, 4> Deduced; | |||
5077 | Deduced.resize(TemplateParams->size()); | |||
5078 | ||||
5079 | // C++0x [temp.deduct.partial]p3: | |||
5080 | // The types used to determine the ordering depend on the context in which | |||
5081 | // the partial ordering is done: | |||
5082 | TemplateDeductionInfo Info(Loc); | |||
5083 | SmallVector<QualType, 4> Args2; | |||
5084 | switch (TPOC) { | |||
5085 | case TPOC_Call: { | |||
5086 | // - In the context of a function call, the function parameter types are | |||
5087 | // used. | |||
5088 | CXXMethodDecl *Method1 = dyn_cast<CXXMethodDecl>(FD1); | |||
5089 | CXXMethodDecl *Method2 = dyn_cast<CXXMethodDecl>(FD2); | |||
5090 | ||||
5091 | // C++11 [temp.func.order]p3: | |||
5092 | // [...] If only one of the function templates is a non-static | |||
5093 | // member, that function template is considered to have a new | |||
5094 | // first parameter inserted in its function parameter list. The | |||
5095 | // new parameter is of type "reference to cv A," where cv are | |||
5096 | // the cv-qualifiers of the function template (if any) and A is | |||
5097 | // the class of which the function template is a member. | |||
5098 | // | |||
5099 | // Note that we interpret this to mean "if one of the function | |||
5100 | // templates is a non-static member and the other is a non-member"; | |||
5101 | // otherwise, the ordering rules for static functions against non-static | |||
5102 | // functions don't make any sense. | |||
5103 | // | |||
5104 | // C++98/03 doesn't have this provision but we've extended DR532 to cover | |||
5105 | // it as wording was broken prior to it. | |||
5106 | SmallVector<QualType, 4> Args1; | |||
5107 | ||||
5108 | unsigned NumComparedArguments = NumCallArguments1; | |||
5109 | ||||
5110 | if (!Method2 && Method1 && !Method1->isStatic()) { | |||
5111 | // Compare 'this' from Method1 against first parameter from Method2. | |||
5112 | AddImplicitObjectParameterType(S.Context, Method1, Args1); | |||
5113 | ++NumComparedArguments; | |||
5114 | } else if (!Method1 && Method2 && !Method2->isStatic()) { | |||
5115 | // Compare 'this' from Method2 against first parameter from Method1. | |||
5116 | AddImplicitObjectParameterType(S.Context, Method2, Args2); | |||
5117 | } else if (Method1 && Method2 && Reversed) { | |||
5118 | // Compare 'this' from Method1 against second parameter from Method2 | |||
5119 | // and 'this' from Method2 against second parameter from Method1. | |||
5120 | AddImplicitObjectParameterType(S.Context, Method1, Args1); | |||
5121 | AddImplicitObjectParameterType(S.Context, Method2, Args2); | |||
5122 | ++NumComparedArguments; | |||
5123 | } | |||
5124 | ||||
5125 | Args1.insert(Args1.end(), Proto1->param_type_begin(), | |||
5126 | Proto1->param_type_end()); | |||
5127 | Args2.insert(Args2.end(), Proto2->param_type_begin(), | |||
5128 | Proto2->param_type_end()); | |||
5129 | ||||
5130 | // C++ [temp.func.order]p5: | |||
5131 | // The presence of unused ellipsis and default arguments has no effect on | |||
5132 | // the partial ordering of function templates. | |||
5133 | if (Args1.size() > NumComparedArguments) | |||
5134 | Args1.resize(NumComparedArguments); | |||
5135 | if (Args2.size() > NumComparedArguments) | |||
5136 | Args2.resize(NumComparedArguments); | |||
5137 | if (Reversed) | |||
5138 | std::reverse(Args2.begin(), Args2.end()); | |||
5139 | if (DeduceTemplateArguments(S, TemplateParams, Args2.data(), Args2.size(), | |||
5140 | Args1.data(), Args1.size(), Info, Deduced, | |||
5141 | TDF_None, /*PartialOrdering=*/true)) | |||
5142 | return false; | |||
5143 | ||||
5144 | break; | |||
5145 | } | |||
5146 | ||||
5147 | case TPOC_Conversion: | |||
5148 | // - In the context of a call to a conversion operator, the return types | |||
5149 | // of the conversion function templates are used. | |||
5150 | if (DeduceTemplateArgumentsByTypeMatch( | |||
5151 | S, TemplateParams, Proto2->getReturnType(), Proto1->getReturnType(), | |||
5152 | Info, Deduced, TDF_None, | |||
5153 | /*PartialOrdering=*/true)) | |||
5154 | return false; | |||
5155 | break; | |||
5156 | ||||
5157 | case TPOC_Other: | |||
5158 | // - In other contexts (14.6.6.2) the function template's function type | |||
5159 | // is used. | |||
5160 | if (DeduceTemplateArgumentsByTypeMatch(S, TemplateParams, | |||
5161 | FD2->getType(), FD1->getType(), | |||
5162 | Info, Deduced, TDF_None, | |||
5163 | /*PartialOrdering=*/true)) | |||
5164 | return false; | |||
5165 | break; | |||
5166 | } | |||
5167 | ||||
5168 | // C++0x [temp.deduct.partial]p11: | |||
5169 | // In most cases, all template parameters must have values in order for | |||
5170 | // deduction to succeed, but for partial ordering purposes a template | |||
5171 | // parameter may remain without a value provided it is not used in the | |||
5172 | // types being used for partial ordering. [ Note: a template parameter used | |||
5173 | // in a non-deduced context is considered used. -end note] | |||
5174 | unsigned ArgIdx = 0, NumArgs = Deduced.size(); | |||
5175 | for (; ArgIdx != NumArgs; ++ArgIdx) | |||
5176 | if (Deduced[ArgIdx].isNull()) | |||
5177 | break; | |||
5178 | ||||
5179 | // FIXME: We fail to implement [temp.deduct.type]p1 along this path. We need | |||
5180 | // to substitute the deduced arguments back into the template and check that | |||
5181 | // we get the right type. | |||
5182 | ||||
5183 | if (ArgIdx == NumArgs) { | |||
5184 | // All template arguments were deduced. FT1 is at least as specialized | |||
5185 | // as FT2. | |||
5186 | return true; | |||
5187 | } | |||
5188 | ||||
5189 | // Figure out which template parameters were used. | |||
5190 | llvm::SmallBitVector UsedParameters(TemplateParams->size()); | |||
5191 | switch (TPOC) { | |||
5192 | case TPOC_Call: | |||
5193 | for (unsigned I = 0, N = Args2.size(); I != N; ++I) | |||
5194 | ::MarkUsedTemplateParameters(S.Context, Args2[I], false, | |||
5195 | TemplateParams->getDepth(), | |||
5196 | UsedParameters); | |||
5197 | break; | |||
5198 | ||||
5199 | case TPOC_Conversion: | |||
5200 | ::MarkUsedTemplateParameters(S.Context, Proto2->getReturnType(), false, | |||
5201 | TemplateParams->getDepth(), UsedParameters); | |||
5202 | break; | |||
5203 | ||||
5204 | case TPOC_Other: | |||
5205 | ::MarkUsedTemplateParameters(S.Context, FD2->getType(), false, | |||
5206 | TemplateParams->getDepth(), | |||
5207 | UsedParameters); | |||
5208 | break; | |||
5209 | } | |||
5210 | ||||
5211 | for (; ArgIdx != NumArgs; ++ArgIdx) | |||
5212 | // If this argument had no value deduced but was used in one of the types | |||
5213 | // used for partial ordering, then deduction fails. | |||
5214 | if (Deduced[ArgIdx].isNull() && UsedParameters[ArgIdx]) | |||
5215 | return false; | |||
5216 | ||||
5217 | return true; | |||
5218 | } | |||
5219 | ||||
5220 | /// Determine whether this a function template whose parameter-type-list | |||
5221 | /// ends with a function parameter pack. | |||
5222 | static bool isVariadicFunctionTemplate(FunctionTemplateDecl *FunTmpl) { | |||
5223 | FunctionDecl *Function = FunTmpl->getTemplatedDecl(); | |||
5224 | unsigned NumParams = Function->getNumParams(); | |||
5225 | if (NumParams == 0) | |||
5226 | return false; | |||
5227 | ||||
5228 | ParmVarDecl *Last = Function->getParamDecl(NumParams - 1); | |||
5229 | if (!Last->isParameterPack()) | |||
5230 | return false; | |||
5231 | ||||
5232 | // Make sure that no previous parameter is a parameter pack. | |||
5233 | while (--NumParams > 0) { | |||
5234 | if (Function->getParamDecl(NumParams - 1)->isParameterPack()) | |||
5235 | return false; | |||
5236 | } | |||
5237 | ||||
5238 | return true; | |||
5239 | } | |||
5240 | ||||
5241 | /// Returns the more specialized function template according | |||
5242 | /// to the rules of function template partial ordering (C++ [temp.func.order]). | |||
5243 | /// | |||
5244 | /// \param FT1 the first function template | |||
5245 | /// | |||
5246 | /// \param FT2 the second function template | |||
5247 | /// | |||
5248 | /// \param TPOC the context in which we are performing partial ordering of | |||
5249 | /// function templates. | |||
5250 | /// | |||
5251 | /// \param NumCallArguments1 The number of arguments in the call to FT1, used | |||
5252 | /// only when \c TPOC is \c TPOC_Call. | |||
5253 | /// | |||
5254 | /// \param NumCallArguments2 The number of arguments in the call to FT2, used | |||
5255 | /// only when \c TPOC is \c TPOC_Call. | |||
5256 | /// | |||
5257 | /// \param Reversed If \c true, exactly one of FT1 and FT2 is an overload | |||
5258 | /// candidate with a reversed parameter order. In this case, the corresponding | |||
5259 | /// P/A pairs between FT1 and FT2 are reversed. | |||
5260 | /// | |||
5261 | /// \returns the more specialized function template. If neither | |||
5262 | /// template is more specialized, returns NULL. | |||
5263 | FunctionTemplateDecl * | |||
5264 | Sema::getMoreSpecializedTemplate(FunctionTemplateDecl *FT1, | |||
5265 | FunctionTemplateDecl *FT2, | |||
5266 | SourceLocation Loc, | |||
5267 | TemplatePartialOrderingContext TPOC, | |||
5268 | unsigned NumCallArguments1, | |||
5269 | unsigned NumCallArguments2, | |||
5270 | bool Reversed) { | |||
5271 | ||||
5272 | auto JudgeByConstraints = [&] () -> FunctionTemplateDecl * { | |||
5273 | llvm::SmallVector<const Expr *, 3> AC1, AC2; | |||
5274 | FT1->getAssociatedConstraints(AC1); | |||
5275 | FT2->getAssociatedConstraints(AC2); | |||
5276 | bool AtLeastAsConstrained1, AtLeastAsConstrained2; | |||
5277 | if (IsAtLeastAsConstrained(FT1, AC1, FT2, AC2, AtLeastAsConstrained1)) | |||
5278 | return nullptr; | |||
5279 | if (IsAtLeastAsConstrained(FT2, AC2, FT1, AC1, AtLeastAsConstrained2)) | |||
5280 | return nullptr; | |||
5281 | if (AtLeastAsConstrained1 == AtLeastAsConstrained2) | |||
5282 | return nullptr; | |||
5283 | return AtLeastAsConstrained1 ? FT1 : FT2; | |||
5284 | }; | |||
5285 | ||||
5286 | bool Better1 = isAtLeastAsSpecializedAs(*this, Loc, FT1, FT2, TPOC, | |||
5287 | NumCallArguments1, Reversed); | |||
5288 | bool Better2 = isAtLeastAsSpecializedAs(*this, Loc, FT2, FT1, TPOC, | |||
5289 | NumCallArguments2, Reversed); | |||
5290 | ||||
5291 | if (Better1 != Better2) // We have a clear winner | |||
5292 | return Better1 ? FT1 : FT2; | |||
5293 | ||||
5294 | if (!Better1 && !Better2) // Neither is better than the other | |||
5295 | return JudgeByConstraints(); | |||
5296 | ||||
5297 | // FIXME: This mimics what GCC implements, but doesn't match up with the | |||
5298 | // proposed resolution for core issue 692. This area needs to be sorted out, | |||
5299 | // but for now we attempt to maintain compatibility. | |||
5300 | bool Variadic1 = isVariadicFunctionTemplate(FT1); | |||
5301 | bool Variadic2 = isVariadicFunctionTemplate(FT2); | |||
5302 | if (Variadic1 != Variadic2) | |||
5303 | return Variadic1? FT2 : FT1; | |||
5304 | ||||
5305 | return JudgeByConstraints(); | |||
5306 | } | |||
5307 | ||||
5308 | /// Determine if the two templates are equivalent. | |||
5309 | static bool isSameTemplate(TemplateDecl *T1, TemplateDecl *T2) { | |||
5310 | if (T1 == T2) | |||
5311 | return true; | |||
5312 | ||||
5313 | if (!T1 || !T2) | |||
5314 | return false; | |||
5315 | ||||
5316 | return T1->getCanonicalDecl() == T2->getCanonicalDecl(); | |||
5317 | } | |||
5318 | ||||
5319 | /// Retrieve the most specialized of the given function template | |||
5320 | /// specializations. | |||
5321 | /// | |||
5322 | /// \param SpecBegin the start iterator of the function template | |||
5323 | /// specializations that we will be comparing. | |||
5324 | /// | |||
5325 | /// \param SpecEnd the end iterator of the function template | |||
5326 | /// specializations, paired with \p SpecBegin. | |||
5327 | /// | |||
5328 | /// \param Loc the location where the ambiguity or no-specializations | |||
5329 | /// diagnostic should occur. | |||
5330 | /// | |||
5331 | /// \param NoneDiag partial diagnostic used to diagnose cases where there are | |||
5332 | /// no matching candidates. | |||
5333 | /// | |||
5334 | /// \param AmbigDiag partial diagnostic used to diagnose an ambiguity, if one | |||
5335 | /// occurs. | |||
5336 | /// | |||
5337 | /// \param CandidateDiag partial diagnostic used for each function template | |||
5338 | /// specialization that is a candidate in the ambiguous ordering. One parameter | |||
5339 | /// in this diagnostic should be unbound, which will correspond to the string | |||
5340 | /// describing the template arguments for the function template specialization. | |||
5341 | /// | |||
5342 | /// \returns the most specialized function template specialization, if | |||
5343 | /// found. Otherwise, returns SpecEnd. | |||
5344 | UnresolvedSetIterator Sema::getMostSpecialized( | |||
5345 | UnresolvedSetIterator SpecBegin, UnresolvedSetIterator SpecEnd, | |||
5346 | TemplateSpecCandidateSet &FailedCandidates, | |||
5347 | SourceLocation Loc, const PartialDiagnostic &NoneDiag, | |||
5348 | const PartialDiagnostic &AmbigDiag, const PartialDiagnostic &CandidateDiag, | |||
5349 | bool Complain, QualType TargetType) { | |||
5350 | if (SpecBegin == SpecEnd) { | |||
5351 | if (Complain) { | |||
5352 | Diag(Loc, NoneDiag); | |||
5353 | FailedCandidates.NoteCandidates(*this, Loc); | |||
5354 | } | |||
5355 | return SpecEnd; | |||
5356 | } | |||
5357 | ||||
5358 | if (SpecBegin + 1 == SpecEnd) | |||
5359 | return SpecBegin; | |||
5360 | ||||
5361 | // Find the function template that is better than all of the templates it | |||
5362 | // has been compared to. | |||
5363 | UnresolvedSetIterator Best = SpecBegin; | |||
5364 | FunctionTemplateDecl *BestTemplate | |||
5365 | = cast<FunctionDecl>(*Best)->getPrimaryTemplate(); | |||
5366 | 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-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 5366, __PRETTY_FUNCTION__)); | |||
5367 | for (UnresolvedSetIterator I = SpecBegin + 1; I != SpecEnd; ++I) { | |||
5368 | FunctionTemplateDecl *Challenger | |||
5369 | = cast<FunctionDecl>(*I)->getPrimaryTemplate(); | |||
5370 | 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-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 5370, __PRETTY_FUNCTION__)); | |||
5371 | if (isSameTemplate(getMoreSpecializedTemplate(BestTemplate, Challenger, | |||
5372 | Loc, TPOC_Other, 0, 0), | |||
5373 | Challenger)) { | |||
5374 | Best = I; | |||
5375 | BestTemplate = Challenger; | |||
5376 | } | |||
5377 | } | |||
5378 | ||||
5379 | // Make sure that the "best" function template is more specialized than all | |||
5380 | // of the others. | |||
5381 | bool Ambiguous = false; | |||
5382 | for (UnresolvedSetIterator I = SpecBegin; I != SpecEnd; ++I) { | |||
5383 | FunctionTemplateDecl *Challenger | |||
5384 | = cast<FunctionDecl>(*I)->getPrimaryTemplate(); | |||
5385 | if (I != Best && | |||
5386 | !isSameTemplate(getMoreSpecializedTemplate(BestTemplate, Challenger, | |||
5387 | Loc, TPOC_Other, 0, 0), | |||
5388 | BestTemplate)) { | |||
5389 | Ambiguous = true; | |||
5390 | break; | |||
5391 | } | |||
5392 | } | |||
5393 | ||||
5394 | if (!Ambiguous) { | |||
5395 | // We found an answer. Return it. | |||
5396 | return Best; | |||
5397 | } | |||
5398 | ||||
5399 | // Diagnose the ambiguity. | |||
5400 | if (Complain) { | |||
5401 | Diag(Loc, AmbigDiag); | |||
5402 | ||||
5403 | // FIXME: Can we order the candidates in some sane way? | |||
5404 | for (UnresolvedSetIterator I = SpecBegin; I != SpecEnd; ++I) { | |||
5405 | PartialDiagnostic PD = CandidateDiag; | |||
5406 | const auto *FD = cast<FunctionDecl>(*I); | |||
5407 | PD << FD << getTemplateArgumentBindingsText( | |||
5408 | FD->getPrimaryTemplate()->getTemplateParameters(), | |||
5409 | *FD->getTemplateSpecializationArgs()); | |||
5410 | if (!TargetType.isNull()) | |||
5411 | HandleFunctionTypeMismatch(PD, FD->getType(), TargetType); | |||
5412 | Diag((*I)->getLocation(), PD); | |||
5413 | } | |||
5414 | } | |||
5415 | ||||
5416 | return SpecEnd; | |||
5417 | } | |||
5418 | ||||
5419 | /// Determine whether one partial specialization, P1, is at least as | |||
5420 | /// specialized than another, P2. | |||
5421 | /// | |||
5422 | /// \tparam TemplateLikeDecl The kind of P2, which must be a | |||
5423 | /// TemplateDecl or {Class,Var}TemplatePartialSpecializationDecl. | |||
5424 | /// \param T1 The injected-class-name of P1 (faked for a variable template). | |||
5425 | /// \param T2 The injected-class-name of P2 (faked for a variable template). | |||
5426 | template<typename TemplateLikeDecl> | |||
5427 | static bool isAtLeastAsSpecializedAs(Sema &S, QualType T1, QualType T2, | |||
5428 | TemplateLikeDecl *P2, | |||
5429 | TemplateDeductionInfo &Info) { | |||
5430 | // C++ [temp.class.order]p1: | |||
5431 | // For two class template partial specializations, the first is at least as | |||
5432 | // specialized as the second if, given the following rewrite to two | |||
5433 | // function templates, the first function template is at least as | |||
5434 | // specialized as the second according to the ordering rules for function | |||
5435 | // templates (14.6.6.2): | |||
5436 | // - the first function template has the same template parameters as the | |||
5437 | // first partial specialization and has a single function parameter | |||
5438 | // whose type is a class template specialization with the template | |||
5439 | // arguments of the first partial specialization, and | |||
5440 | // - the second function template has the same template parameters as the | |||
5441 | // second partial specialization and has a single function parameter | |||
5442 | // whose type is a class template specialization with the template | |||
5443 | // arguments of the second partial specialization. | |||
5444 | // | |||
5445 | // Rather than synthesize function templates, we merely perform the | |||
5446 | // equivalent partial ordering by performing deduction directly on | |||
5447 | // the template arguments of the class template partial | |||
5448 | // specializations. This computation is slightly simpler than the | |||
5449 | // general problem of function template partial ordering, because | |||
5450 | // class template partial specializations are more constrained. We | |||
5451 | // know that every template parameter is deducible from the class | |||
5452 | // template partial specialization's template arguments, for | |||
5453 | // example. | |||
5454 | SmallVector<DeducedTemplateArgument, 4> Deduced; | |||
5455 | ||||
5456 | // Determine whether P1 is at least as specialized as P2. | |||
5457 | Deduced.resize(P2->getTemplateParameters()->size()); | |||
5458 | if (DeduceTemplateArgumentsByTypeMatch(S, P2->getTemplateParameters(), | |||
5459 | T2, T1, Info, Deduced, TDF_None, | |||
5460 | /*PartialOrdering=*/true)) | |||
5461 | return false; | |||
5462 | ||||
5463 | SmallVector<TemplateArgument, 4> DeducedArgs(Deduced.begin(), | |||
5464 | Deduced.end()); | |||
5465 | Sema::InstantiatingTemplate Inst(S, Info.getLocation(), P2, DeducedArgs, | |||
5466 | Info); | |||
5467 | auto *TST1 = T1->castAs<TemplateSpecializationType>(); | |||
5468 | bool AtLeastAsSpecialized; | |||
5469 | S.runWithSufficientStackSpace(Info.getLocation(), [&] { | |||
5470 | AtLeastAsSpecialized = !FinishTemplateArgumentDeduction( | |||
5471 | S, P2, /*IsPartialOrdering=*/true, | |||
5472 | TemplateArgumentList(TemplateArgumentList::OnStack, | |||
5473 | TST1->template_arguments()), | |||
5474 | Deduced, Info); | |||
5475 | }); | |||
5476 | return AtLeastAsSpecialized; | |||
5477 | } | |||
5478 | ||||
5479 | /// Returns the more specialized class template partial specialization | |||
5480 | /// according to the rules of partial ordering of class template partial | |||
5481 | /// specializations (C++ [temp.class.order]). | |||
5482 | /// | |||
5483 | /// \param PS1 the first class template partial specialization | |||
5484 | /// | |||
5485 | /// \param PS2 the second class template partial specialization | |||
5486 | /// | |||
5487 | /// \returns the more specialized class template partial specialization. If | |||
5488 | /// neither partial specialization is more specialized, returns NULL. | |||
5489 | ClassTemplatePartialSpecializationDecl * | |||
5490 | Sema::getMoreSpecializedPartialSpecialization( | |||
5491 | ClassTemplatePartialSpecializationDecl *PS1, | |||
5492 | ClassTemplatePartialSpecializationDecl *PS2, | |||
5493 | SourceLocation Loc) { | |||
5494 | QualType PT1 = PS1->getInjectedSpecializationType(); | |||
5495 | QualType PT2 = PS2->getInjectedSpecializationType(); | |||
5496 | ||||
5497 | TemplateDeductionInfo Info(Loc); | |||
5498 | bool Better1 = isAtLeastAsSpecializedAs(*this, PT1, PT2, PS2, Info); | |||
5499 | bool Better2 = isAtLeastAsSpecializedAs(*this, PT2, PT1, PS1, Info); | |||
5500 | ||||
5501 | if (!Better1 && !Better2) | |||
5502 | return nullptr; | |||
5503 | if (Better1 && Better2) { | |||
5504 | llvm::SmallVector<const Expr *, 3> AC1, AC2; | |||
5505 | PS1->getAssociatedConstraints(AC1); | |||
5506 | PS2->getAssociatedConstraints(AC2); | |||
5507 | bool AtLeastAsConstrained1, AtLeastAsConstrained2; | |||
5508 | if (IsAtLeastAsConstrained(PS1, AC1, PS2, AC2, AtLeastAsConstrained1)) | |||
5509 | return nullptr; | |||
5510 | if (IsAtLeastAsConstrained(PS2, AC2, PS1, AC1, AtLeastAsConstrained2)) | |||
5511 | return nullptr; | |||
5512 | if (AtLeastAsConstrained1 == AtLeastAsConstrained2) | |||
5513 | return nullptr; | |||
5514 | return AtLeastAsConstrained1 ? PS1 : PS2; | |||
5515 | } | |||
5516 | ||||
5517 | return Better1 ? PS1 : PS2; | |||
5518 | } | |||
5519 | ||||
5520 | bool Sema::isMoreSpecializedThanPrimary( | |||
5521 | ClassTemplatePartialSpecializationDecl *Spec, TemplateDeductionInfo &Info) { | |||
5522 | ClassTemplateDecl *Primary = Spec->getSpecializedTemplate(); | |||
5523 | QualType PrimaryT = Primary->getInjectedClassNameSpecialization(); | |||
5524 | QualType PartialT = Spec->getInjectedSpecializationType(); | |||
5525 | if (!isAtLeastAsSpecializedAs(*this, PartialT, PrimaryT, Primary, Info)) | |||
5526 | return false; | |||
5527 | if (!isAtLeastAsSpecializedAs(*this, PrimaryT, PartialT, Spec, Info)) | |||
5528 | return true; | |||
5529 | Info.clearSFINAEDiagnostic(); | |||
5530 | llvm::SmallVector<const Expr *, 3> PrimaryAC, SpecAC; | |||
5531 | Primary->getAssociatedConstraints(PrimaryAC); | |||
5532 | Spec->getAssociatedConstraints(SpecAC); | |||
5533 | bool AtLeastAsConstrainedPrimary, AtLeastAsConstrainedSpec; | |||
5534 | if (IsAtLeastAsConstrained(Spec, SpecAC, Primary, PrimaryAC, | |||
5535 | AtLeastAsConstrainedSpec)) | |||
5536 | return false; | |||
5537 | if (!AtLeastAsConstrainedSpec) | |||
5538 | return false; | |||
5539 | if (IsAtLeastAsConstrained(Primary, PrimaryAC, Spec, SpecAC, | |||
5540 | AtLeastAsConstrainedPrimary)) | |||
5541 | return false; | |||
5542 | return !AtLeastAsConstrainedPrimary; | |||
5543 | } | |||
5544 | ||||
5545 | VarTemplatePartialSpecializationDecl * | |||
5546 | Sema::getMoreSpecializedPartialSpecialization( | |||
5547 | VarTemplatePartialSpecializationDecl *PS1, | |||
5548 | VarTemplatePartialSpecializationDecl *PS2, SourceLocation Loc) { | |||
5549 | // Pretend the variable template specializations are class template | |||
5550 | // specializations and form a fake injected class name type for comparison. | |||
5551 | 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-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 5553, __PRETTY_FUNCTION__)) | |||
5552 | "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-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 5553, __PRETTY_FUNCTION__)) | |||
5553 | " 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-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 5553, __PRETTY_FUNCTION__)); | |||
5554 | TemplateName Name(PS1->getSpecializedTemplate()); | |||
5555 | TemplateName CanonTemplate = Context.getCanonicalTemplateName(Name); | |||
5556 | QualType PT1 = Context.getTemplateSpecializationType( | |||
5557 | CanonTemplate, PS1->getTemplateArgs().asArray()); | |||
5558 | QualType PT2 = Context.getTemplateSpecializationType( | |||
5559 | CanonTemplate, PS2->getTemplateArgs().asArray()); | |||
5560 | ||||
5561 | TemplateDeductionInfo Info(Loc); | |||
5562 | bool Better1 = isAtLeastAsSpecializedAs(*this, PT1, PT2, PS2, Info); | |||
5563 | bool Better2 = isAtLeastAsSpecializedAs(*this, PT2, PT1, PS1, Info); | |||
5564 | ||||
5565 | if (!Better1 && !Better2) | |||
5566 | return nullptr; | |||
5567 | if (Better1 && Better2) { | |||
5568 | llvm::SmallVector<const Expr *, 3> AC1, AC2; | |||
5569 | PS1->getAssociatedConstraints(AC1); | |||
5570 | PS2->getAssociatedConstraints(AC2); | |||
5571 | bool AtLeastAsConstrained1, AtLeastAsConstrained2; | |||
5572 | if (IsAtLeastAsConstrained(PS1, AC1, PS2, AC2, AtLeastAsConstrained1)) | |||
5573 | return nullptr; | |||
5574 | if (IsAtLeastAsConstrained(PS2, AC2, PS1, AC1, AtLeastAsConstrained2)) | |||
5575 | return nullptr; | |||
5576 | if (AtLeastAsConstrained1 == AtLeastAsConstrained2) | |||
5577 | return nullptr; | |||
5578 | return AtLeastAsConstrained1 ? PS1 : PS2; | |||
5579 | } | |||
5580 | ||||
5581 | return Better1 ? PS1 : PS2; | |||
5582 | } | |||
5583 | ||||
5584 | bool Sema::isMoreSpecializedThanPrimary( | |||
5585 | VarTemplatePartialSpecializationDecl *Spec, TemplateDeductionInfo &Info) { | |||
5586 | TemplateDecl *Primary = Spec->getSpecializedTemplate(); | |||
5587 | // FIXME: Cache the injected template arguments rather than recomputing | |||
5588 | // them for each partial specialization. | |||
5589 | SmallVector<TemplateArgument, 8> PrimaryArgs; | |||
5590 | Context.getInjectedTemplateArgs(Primary->getTemplateParameters(), | |||
5591 | PrimaryArgs); | |||
5592 | ||||
5593 | TemplateName CanonTemplate = | |||
5594 | Context.getCanonicalTemplateName(TemplateName(Primary)); | |||
5595 | QualType PrimaryT = Context.getTemplateSpecializationType( | |||
5596 | CanonTemplate, PrimaryArgs); | |||
5597 | QualType PartialT = Context.getTemplateSpecializationType( | |||
5598 | CanonTemplate, Spec->getTemplateArgs().asArray()); | |||
5599 | ||||
5600 | if (!isAtLeastAsSpecializedAs(*this, PartialT, PrimaryT, Primary, Info)) | |||
5601 | return false; | |||
5602 | if (!isAtLeastAsSpecializedAs(*this, PrimaryT, PartialT, Spec, Info)) | |||
5603 | return true; | |||
5604 | Info.clearSFINAEDiagnostic(); | |||
5605 | llvm::SmallVector<const Expr *, 3> PrimaryAC, SpecAC; | |||
5606 | Primary->getAssociatedConstraints(PrimaryAC); | |||
5607 | Spec->getAssociatedConstraints(SpecAC); | |||
5608 | bool AtLeastAsConstrainedPrimary, AtLeastAsConstrainedSpec; | |||
5609 | if (IsAtLeastAsConstrained(Spec, SpecAC, Primary, PrimaryAC, | |||
5610 | AtLeastAsConstrainedSpec)) | |||
5611 | return false; | |||
5612 | if (!AtLeastAsConstrainedSpec) | |||
5613 | return false; | |||
5614 | if (IsAtLeastAsConstrained(Primary, PrimaryAC, Spec, SpecAC, | |||
5615 | AtLeastAsConstrainedPrimary)) | |||
5616 | return false; | |||
5617 | return !AtLeastAsConstrainedPrimary; | |||
5618 | } | |||
5619 | ||||
5620 | bool Sema::isTemplateTemplateParameterAtLeastAsSpecializedAs( | |||
5621 | TemplateParameterList *P, TemplateDecl *AArg, SourceLocation Loc) { | |||
5622 | // C++1z [temp.arg.template]p4: (DR 150) | |||
5623 | // A template template-parameter P is at least as specialized as a | |||
5624 | // template template-argument A if, given the following rewrite to two | |||
5625 | // function templates... | |||
5626 | ||||
5627 | // Rather than synthesize function templates, we merely perform the | |||
5628 | // equivalent partial ordering by performing deduction directly on | |||
5629 | // the template parameter lists of the template template parameters. | |||
5630 | // | |||
5631 | // Given an invented class template X with the template parameter list of | |||
5632 | // A (including default arguments): | |||
5633 | TemplateName X = Context.getCanonicalTemplateName(TemplateName(AArg)); | |||
5634 | TemplateParameterList *A = AArg->getTemplateParameters(); | |||
5635 | ||||
5636 | // - Each function template has a single function parameter whose type is | |||
5637 | // a specialization of X with template arguments corresponding to the | |||
5638 | // template parameters from the respective function template | |||
5639 | SmallVector<TemplateArgument, 8> AArgs; | |||
5640 | Context.getInjectedTemplateArgs(A, AArgs); | |||
5641 | ||||
5642 | // Check P's arguments against A's parameter list. This will fill in default | |||
5643 | // template arguments as needed. AArgs are already correct by construction. | |||
5644 | // We can't just use CheckTemplateIdType because that will expand alias | |||
5645 | // templates. | |||
5646 | SmallVector<TemplateArgument, 4> PArgs; | |||
5647 | { | |||
5648 | SFINAETrap Trap(*this); | |||
5649 | ||||
5650 | Context.getInjectedTemplateArgs(P, PArgs); | |||
5651 | TemplateArgumentListInfo PArgList(P->getLAngleLoc(), | |||
5652 | P->getRAngleLoc()); | |||
5653 | for (unsigned I = 0, N = P->size(); I != N; ++I) { | |||
5654 | // Unwrap packs that getInjectedTemplateArgs wrapped around pack | |||
5655 | // expansions, to form an "as written" argument list. | |||
5656 | TemplateArgument Arg = PArgs[I]; | |||
5657 | if (Arg.getKind() == TemplateArgument::Pack) { | |||
5658 | 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-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaTemplateDeduction.cpp" , 5658, __PRETTY_FUNCTION__)); | |||
5659 | Arg = *Arg.pack_begin(); | |||
5660 | } | |||
5661 | PArgList.addArgument(getTrivialTemplateArgumentLoc( | |||
5662 | Arg, QualType(), P->getParam(I)->getLocation())); | |||
5663 | } | |||
5664 | PArgs.clear(); | |||
5665 | ||||
5666 | // C++1z [temp.arg.template]p3: | |||
5667 | // If the rewrite produces an invalid type, then P is not at least as | |||
5668 | // specialized as A. | |||
5669 | if (CheckTemplateArgumentList(AArg, Loc, PArgList, false, PArgs) || | |||
5670 | Trap.hasErrorOccurred()) | |||
5671 | return false; | |||
5672 | } | |||
5673 | ||||
5674 | QualType AType = Context.getTemplateSpecializationType(X, AArgs); | |||
5675 | QualType PType = Context.getTemplateSpecializationType(X, PArgs); | |||
5676 | ||||
5677 | // ... the function template corresponding to P is at least as specialized | |||
5678 | // as the function template corresponding to A according to the partial | |||
5679 | // ordering rules for function templates. | |||
5680 | TemplateDeductionInfo Info(Loc, A->getDepth()); | |||
5681 | return isAtLeastAsSpecializedAs(*this, PType, AType, AArg, Info); | |||
5682 | } | |||
5683 | ||||
5684 | namespace { | |||
5685 | struct MarkUsedTemplateParameterVisitor : | |||
5686 | RecursiveASTVisitor<MarkUsedTemplateParameterVisitor> { | |||
5687 | llvm::SmallBitVector &Used; | |||
5688 | unsigned Depth; | |||
5689 | ||||
5690 | MarkUsedTemplateParameterVisitor(llvm::SmallBitVector &Used, | |||
5691 | unsigned Depth) | |||
5692 | : Used(Used), Depth(Depth) { } | |||
5693 | ||||
5694 | bool VisitTemplateTypeParmType(TemplateTypeParmType *T) { | |||
5695 | if (T->getDepth() == Depth) | |||
5696 | Used[T->getIndex()] = true; | |||
5697 | return true; | |||
5698 | } | |||
5699 | ||||
5700 | bool TraverseTemplateName(TemplateName Template) { | |||
5701 | if (auto *TTP = | |||
5702 | dyn_cast<TemplateTemplateParmDecl>(Template.getAsTemplateDecl())) | |||
5703 | if (TTP->getDepth() == Depth) | |||
5704 | Used[TTP->getIndex()] = true; | |||
5705 | RecursiveASTVisitor<MarkUsedTemplateParameterVisitor>:: | |||
5706 | TraverseTemplateName(Template); | |||
5707 | return true; | |||
5708 | } | |||
5709 | ||||
5710 | bool VisitDeclRefExpr(DeclRefExpr *E) { | |||
5711 | if (auto *NTTP = dyn_cast<NonTypeTemplateParmDecl>(E->getDecl())) | |||
5712 | if (NTTP->getDepth() == Depth) | |||
5713 | Used[NTTP->getIndex()] = true; | |||
5714 | return true; | |||
5715 | } | |||
5716 | }; | |||
5717 | } | |||
5718 | ||||
5719 | /// Mark the template parameters that are used by the given | |||
5720 | /// expression. | |||
5721 | static void | |||
5722 | MarkUsedTemplateParameters(ASTContext &Ctx, | |||
5723 | const Expr *E, | |||
5724 | bool OnlyDeduced, | |||
5725 | unsigned Depth, | |||
5726 | llvm::SmallBitVector &Used) { | |||
5727 | if (!OnlyDeduced) { | |||
5728 | MarkUsedTemplateParameterVisitor(Used, Depth) | |||
5729 | .TraverseStmt(const_cast<Expr *>(E)); | |||
5730 | return; | |||
5731 | } | |||
5732 | ||||
5733 | // We can deduce from a pack expansion. | |||
5734 | if (const PackExpansionExpr *Expansion = dyn_cast<PackExpansionExpr>(E)) | |||
5735 | E = Expansion->getPattern(); | |||
5736 | ||||
5737 | const NonTypeTemplateParmDecl *NTTP = getDeducedParameterFromExpr(E, Depth); | |||
5738 | if (!NTTP) | |||
5739 | return; | |||
5740 | ||||
5741 | if (NTTP->getDepth() == Depth) | |||
5742 | Used[NTTP->getIndex()] = true; | |||
5743 | ||||
5744 | // In C++17 mode, additional arguments may be deduced from the type of a | |||
5745 | // non-type argument. | |||
5746 | if (Ctx.getLangOpts().CPlusPlus17) | |||
5747 | MarkUsedTemplateParameters(Ctx, NTTP->getType(), OnlyDeduced, Depth, Used); | |||
5748 | } | |||
5749 | ||||
5750 | /// Mark the template parameters that are used by the given | |||
5751 | /// nested name specifier. | |||
5752 | static void | |||
5753 | MarkUsedTemplateParameters(ASTContext &Ctx, | |||
5754 | NestedNameSpecifier *NNS, | |||
5755 | bool OnlyDeduced, | |||
5756 | unsigned Depth, | |||
5757 | llvm::SmallBitVector &Used) { | |||
5758 | if (!NNS) | |||
5759 | return; | |||
5760 | ||||
5761 | MarkUsedTemplateParameters(Ctx, NNS->getPrefix(), OnlyDeduced, Depth, | |||
5762 | Used); | |||
5763 | MarkUsedTemplateParameters(Ctx, QualType(NNS->getAsType(), 0), | |||
5764 | OnlyDeduced, Depth, Used); | |||
5765 | } | |||
5766 | ||||
5767 | /// Mark the template parameters that are used by the given | |||
5768 | /// template name. | |||
5769 | static void | |||
5770 | MarkUsedTemplateParameters(ASTContext &Ctx, | |||
5771 | TemplateName Name, | |||
5772 | bool OnlyDeduced, | |||
5773 | unsigned Depth, | |||
5774 | llvm::SmallBitVector &Used) { | |||
5775 | if (TemplateDecl *Template = Name.getAsTemplateDecl()) { | |||
5776 | if (TemplateTemplateParmDecl *TTP | |||
5777 | = dyn_cast<TemplateTemplateParmDecl>(Template)) { | |||
5778 | if (TTP->getDepth() == Depth) | |||
5779 | Used[TTP->getIndex()] = true; | |||
5780 | } | |||
5781 | return; | |||
5782 | } | |||
5783 | ||||
5784 | if (QualifiedTemplateName *QTN = Name.getAsQualifiedTemplateName()) | |||
5785 | MarkUsedTemplateParameters(Ctx, QTN->getQualifier(), OnlyDeduced, | |||
5786 | Depth, Used); | |||
5787 | if (DependentTemplateName *DTN = Name.getAsDependentTemplateName()) | |||
5788 | MarkUsedTemplateParameters(Ctx, DTN->getQualifier(), OnlyDeduced, | |||
5789 | Depth, Used); | |||
5790 | } | |||
5791 | ||||
5792 | /// Mark the template parameters that are used by the given | |||
5793 | /// type. | |||
5794 | static void | |||
5795 | MarkUsedTemplateParameters(ASTContext &Ctx, QualType T, | |||
5796 | bool OnlyDeduced, | |||
5797 | unsigned Depth, | |||
5798 | llvm::SmallBitVector &Used) { | |||
5799 | if (T.isNull()) | |||
5800 | return; | |||
5801 | ||||
5802 | // Non-dependent types have nothing deducible | |||
5803 | if (!T->isDependentType()) | |||
5804 | return; | |||
5805 | ||||
5806 | T = Ctx.getCanonicalType(T); | |||
5807 | switch (T->getTypeClass()) { | |||
5808 | case Type::Pointer: | |||
5809 | MarkUsedTemplateParameters(Ctx, | |||
5810 | cast<PointerType>(T)->getPointeeType(), | |||
5811 | OnlyDeduced, | |||
5812 | Depth, | |||
5813 | Used); | |||
5814 | break; | |||
5815 | ||||
5816 | case Type::BlockPointer: | |||
5817 | MarkUsedTemplateParameters(Ctx, | |||
5818 | cast<BlockPointerType>(T)->getPointeeType(), | |||
5819 | OnlyDeduced, | |||
5820 | Depth, | |||
5821 | Used); | |||
5822 | break; | |||
5823 | ||||
5824 | case Type::LValueReference: | |||
5825 | case Type::RValueReference: | |||
5826 | MarkUsedTemplateParameters(Ctx, | |||
5827 | cast<ReferenceType>(T)->getPointeeType(), | |||
5828 | OnlyDeduced, | |||
5829 | Depth, | |||
5830 | Used); | |||
5831 | break; | |||
5832 | ||||
5833 | case Type::MemberPointer: { | |||
5834 | const MemberPointerType *MemPtr = cast<MemberPointerType>(T.getTypePtr()); | |||
5835 | MarkUsedTemplateParameters(Ctx, MemPtr->getPointeeType(), OnlyDeduced, | |||
5836 | Depth, Used); | |||
5837 | MarkUsedTemplateParameters(Ctx, QualType(MemPtr->getClass(), 0), | |||
5838 | OnlyDeduced, Depth, Used); | |||
5839 | break; | |||
5840 | } | |||
5841 | ||||
5842 | case Type::DependentSizedArray: | |||
5843 | MarkUsedTemplateParameters(Ctx, | |||
5844 | cast<DependentSizedArrayType>(T)->getSizeExpr(), | |||
5845 | OnlyDeduced, Depth, Used); | |||
5846 | // Fall through to check the element type | |||
5847 | LLVM_FALLTHROUGH[[gnu::fallthrough]]; | |||
5848 | ||||
5849 | case Type::ConstantArray: | |||
5850 | case Type::IncompleteArray: | |||
5851 | MarkUsedTemplateParameters(Ctx, | |||
5852 | cast<ArrayType>(T)->getElementType(), | |||
5853 | OnlyDeduced, Depth, Used); | |||
5854 | break; | |||
5855 | ||||
5856 | case Type::Vector: | |||
5857 | case Type::ExtVector: | |||
5858 | MarkUsedTemplateParameters(Ctx, | |||
5859 | cast<VectorType>(T)->getElementType(), | |||
5860 | OnlyDeduced, Depth, Used); | |||
5861 | break; | |||
5862 | ||||
5863 | case Type::DependentVector: { | |||
5864 | const auto *VecType = cast<DependentVectorType>(T); | |||
5865 | MarkUsedTemplateParameters(Ctx, VecType->getElementType(), OnlyDeduced, | |||
5866 | Depth, Used); | |||
5867 | MarkUsedTemplateParameters(Ctx, VecType->getSizeExpr(), OnlyDeduced, Depth, | |||
5868 | Used); | |||
5869 | break; | |||
5870 | } | |||
5871 | case Type::DependentSizedExtVector: { | |||
5872 | const DependentSizedExtVectorType *VecType | |||
5873 | = cast<DependentSizedExtVectorType>(T); | |||
5874 | MarkUsedTemplateParameters(Ctx, VecType->getElementType(), OnlyDeduced, | |||
5875 | Depth, Used); | |||
5876 | MarkUsedTemplateParameters(Ctx, VecType->getSizeExpr(), OnlyDeduced, | |||
5877 | Depth, Used); | |||
5878 | break; | |||
5879 | } | |||
5880 | ||||
5881 | case Type::DependentAddressSpace: { | |||
5882 | const DependentAddressSpaceType *DependentASType = | |||
5883 | cast<DependentAddressSpaceType>(T); | |||
5884 | MarkUsedTemplateParameters(Ctx, DependentASType->getPointeeType(), | |||
5885 | OnlyDeduced, Depth, Used); | |||
5886 | MarkUsedTemplateParameters(Ctx, | |||
5887 | DependentASType->getAddrSpaceExpr(), | |||
5888 | OnlyDeduced, Depth, Used); | |||
5889 | break; | |||
5890 | } | |||
5891 | ||||
5892 | case Type::ConstantMatrix: { | |||
5893 | const ConstantMatrixType *MatType = cast<ConstantMatrixType>(T); | |||
5894 | MarkUsedTemplateParameters(Ctx, MatType->getElementType(), OnlyDeduced, | |||
5895 | Depth, Used); | |||
5896 | break; | |||
5897 | } | |||
5898 | ||||
5899 | case Type::DependentSizedMatrix: { | |||
5900 | const DependentSizedMatrixType *MatType = cast<DependentSizedMatrixType>(T); | |||
5901 | MarkUsedTemplateParameters(Ctx, MatType->getElementType(), OnlyDeduced, | |||
5902 | Depth, Used); | |||
5903 | MarkUsedTemplateParameters(Ctx, MatType->getRowExpr(), OnlyDeduced, Depth, | |||
5904 | Used); | |||
5905 | MarkUsedTemplateParameters(Ctx, MatType->getColumnExpr(), OnlyDeduced, | |||
5906 | Depth, Used); | |||
5907 | break; | |||
5908 | } | |||
5909 | ||||
5910 | case Type::FunctionProto: { | |||
5911 | const FunctionProtoType *Proto = cast<FunctionProtoType>(T); | |||
5912 | MarkUsedTemplateParameters(Ctx, Proto->getReturnType(), OnlyDeduced, Depth, | |||
5913 | Used); | |||
5914 | for (unsigned I = 0, N = Proto->getNumParams(); I != N; ++I) { | |||
5915 | // C++17 [temp.deduct.type]p5: | |||
5916 | // The non-deduced contexts are: [...] | |||
5917 | // -- A function parameter pack that does not occur at the end of the | |||
5918 | // parameter-declaration-list. | |||
5919 | if (!OnlyDeduced || I + 1 == N || | |||
5920 | !Proto->getParamType(I)->getAs<PackExpansionType>()) { | |||
5921 | MarkUsedTemplateParameters(Ctx, Proto->getParamType(I), OnlyDeduced, | |||
5922 | Depth, Used); | |||
5923 | } else { | |||
5924 | // FIXME: C++17 [temp.deduct.call]p1: | |||
5925 | // When a function parameter pack appears in a non-deduced context, | |||
5926 | // the type of that pack is never deduced. | |||
5927 | // | |||
5928 | // We should also track a set of "never deduced" parameters, and | |||
5929 | // subtract that from the list of deduced parameters after marking. | |||
5930 | } | |||
5931 | } | |||
5932 | if (auto *E = Proto->getNoexceptExpr()) | |||
5933 | MarkUsedTemplateParameters(Ctx, E, OnlyDeduced, Depth, Used); | |||
5934 | break; | |||
5935 | } | |||
5936 | ||||
5937 | case Type::TemplateTypeParm: { | |||
5938 | const TemplateTypeParmType *TTP = cast<TemplateTypeParmType>(T); | |||
5939 | if (TTP->getDepth() == Depth) | |||
5940 | Used[TTP->getIndex()] = true; | |||
5941 | break; | |||
5942 | } | |||
5943 | ||||
5944 | case Type::SubstTemplateTypeParmPack: { | |||
5945 | const SubstTemplateTypeParmPackType *Subst | |||
5946 | = cast<SubstTemplateTypeParmPackType>(T); | |||
5947 | MarkUsedTemplateParameters(Ctx, | |||
5948 | QualType(Subst->getReplacedParameter(), 0), | |||
5949 | OnlyDeduced, Depth, Used); | |||
5950 | MarkUsedTemplateParameters(Ctx, Subst->getArgumentPack(), | |||
5951 | OnlyDeduced, Depth, Used); | |||
5952 | break; | |||
5953 | } | |||
5954 | ||||
5955 | case Type::InjectedClassName: | |||
5956 | T = cast<InjectedClassNameType>(T)->getInjectedSpecializationType(); | |||
5957 | LLVM_FALLTHROUGH[[gnu::fallthrough]]; | |||
5958 | ||||
5959 | case Type::TemplateSpecialization: { | |||
5960 | const TemplateSpecializationType *Spec | |||
5961 | = cast<TemplateSpecializationType>(T); | |||
5962 | MarkUsedTemplateParameters(Ctx, Spec->getTemplateName(), OnlyDeduced, | |||
5963 | Depth, Used); | |||
5964 | ||||
5965 | // C++0x [temp.deduct.type]p9: | |||
5966 | // If the template argument list of P contains a pack expansion that is | |||
5967 | // not the last template argument, the entire template argument list is a | |||
5968 | // non-deduced context. | |||
5969 | if (OnlyDeduced && | |||
5970 | hasPackExpansionBeforeEnd(Spec->template_arguments())) | |||
5971 | break; | |||
5972 | ||||
5973 | for (unsigned I = 0, N = Spec->getNumArgs(); I != N; ++I) | |||
5974 | MarkUsedTemplateParameters(Ctx, Spec->getArg(I), OnlyDeduced, Depth, | |||
5975 | Used); | |||
5976 | break; | |||
5977 | } | |||
5978 | ||||
5979 | case Type::Complex: | |||
5980 | if (!OnlyDeduced) | |||
5981 | MarkUsedTemplateParameters(Ctx, | |||
5982 | cast<ComplexType>(T)->getElementType(), | |||