File: | build/llvm-toolchain-snapshot-15~++20220420111733+e13d2efed663/clang/lib/Sema/SemaTemplateDeduction.cpp |
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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 DeduceTemplateArgumentsByTypeMatch( | |||
135 | Sema &S, TemplateParameterList *TemplateParams, QualType Param, | |||
136 | QualType Arg, TemplateDeductionInfo &Info, | |||
137 | SmallVectorImpl<DeducedTemplateArgument> &Deduced, unsigned TDF, | |||
138 | bool PartialOrdering = false, bool DeducedFromArrayBound = false); | |||
139 | ||||
140 | static Sema::TemplateDeductionResult | |||
141 | DeduceTemplateArguments(Sema &S, TemplateParameterList *TemplateParams, | |||
142 | ArrayRef<TemplateArgument> Ps, | |||
143 | ArrayRef<TemplateArgument> As, | |||
144 | TemplateDeductionInfo &Info, | |||
145 | SmallVectorImpl<DeducedTemplateArgument> &Deduced, | |||
146 | bool NumberOfArgumentsMustMatch); | |||
147 | ||||
148 | static void MarkUsedTemplateParameters(ASTContext &Ctx, | |||
149 | const TemplateArgument &TemplateArg, | |||
150 | bool OnlyDeduced, unsigned Depth, | |||
151 | llvm::SmallBitVector &Used); | |||
152 | ||||
153 | static void MarkUsedTemplateParameters(ASTContext &Ctx, QualType T, | |||
154 | bool OnlyDeduced, unsigned Level, | |||
155 | llvm::SmallBitVector &Deduced); | |||
156 | ||||
157 | /// If the given expression is of a form that permits the deduction | |||
158 | /// of a non-type template parameter, return the declaration of that | |||
159 | /// non-type template parameter. | |||
160 | static const NonTypeTemplateParmDecl * | |||
161 | getDeducedParameterFromExpr(const Expr *E, unsigned Depth) { | |||
162 | // If we are within an alias template, the expression may have undergone | |||
163 | // any number of parameter substitutions already. | |||
164 | while (true) { | |||
165 | if (const auto *IC = dyn_cast<ImplicitCastExpr>(E)) | |||
166 | E = IC->getSubExpr(); | |||
167 | else if (const auto *CE = dyn_cast<ConstantExpr>(E)) | |||
168 | E = CE->getSubExpr(); | |||
169 | else if (const auto *Subst = dyn_cast<SubstNonTypeTemplateParmExpr>(E)) | |||
170 | E = Subst->getReplacement(); | |||
171 | else if (const auto *CCE = dyn_cast<CXXConstructExpr>(E)) { | |||
172 | // Look through implicit copy construction from an lvalue of the same type. | |||
173 | if (CCE->getParenOrBraceRange().isValid()) | |||
174 | break; | |||
175 | // Note, there could be default arguments. | |||
176 | assert(CCE->getNumArgs() >= 1 && "implicit construct expr should have 1 arg")(static_cast <bool> (CCE->getNumArgs() >= 1 && "implicit construct expr should have 1 arg") ? void (0) : __assert_fail ("CCE->getNumArgs() >= 1 && \"implicit construct expr should have 1 arg\"" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 176, __extension__ __PRETTY_FUNCTION__)); | |||
177 | E = CCE->getArg(0); | |||
178 | } else | |||
179 | break; | |||
180 | } | |||
181 | ||||
182 | if (const auto *DRE = dyn_cast<DeclRefExpr>(E)) | |||
183 | if (const auto *NTTP = dyn_cast<NonTypeTemplateParmDecl>(DRE->getDecl())) | |||
184 | if (NTTP->getDepth() == Depth) | |||
185 | return NTTP; | |||
186 | ||||
187 | return nullptr; | |||
188 | } | |||
189 | ||||
190 | static const NonTypeTemplateParmDecl * | |||
191 | getDeducedParameterFromExpr(TemplateDeductionInfo &Info, Expr *E) { | |||
192 | return getDeducedParameterFromExpr(E, Info.getDeducedDepth()); | |||
193 | } | |||
194 | ||||
195 | /// Determine whether two declaration pointers refer to the same | |||
196 | /// declaration. | |||
197 | static bool isSameDeclaration(Decl *X, Decl *Y) { | |||
198 | if (NamedDecl *NX = dyn_cast<NamedDecl>(X)) | |||
199 | X = NX->getUnderlyingDecl(); | |||
200 | if (NamedDecl *NY = dyn_cast<NamedDecl>(Y)) | |||
201 | Y = NY->getUnderlyingDecl(); | |||
202 | ||||
203 | return X->getCanonicalDecl() == Y->getCanonicalDecl(); | |||
204 | } | |||
205 | ||||
206 | /// Verify that the given, deduced template arguments are compatible. | |||
207 | /// | |||
208 | /// \returns The deduced template argument, or a NULL template argument if | |||
209 | /// the deduced template arguments were incompatible. | |||
210 | static DeducedTemplateArgument | |||
211 | checkDeducedTemplateArguments(ASTContext &Context, | |||
212 | const DeducedTemplateArgument &X, | |||
213 | const DeducedTemplateArgument &Y) { | |||
214 | // We have no deduction for one or both of the arguments; they're compatible. | |||
215 | if (X.isNull()) | |||
216 | return Y; | |||
217 | if (Y.isNull()) | |||
218 | return X; | |||
219 | ||||
220 | // If we have two non-type template argument values deduced for the same | |||
221 | // parameter, they must both match the type of the parameter, and thus must | |||
222 | // match each other's type. As we're only keeping one of them, we must check | |||
223 | // for that now. The exception is that if either was deduced from an array | |||
224 | // bound, the type is permitted to differ. | |||
225 | if (!X.wasDeducedFromArrayBound() && !Y.wasDeducedFromArrayBound()) { | |||
226 | QualType XType = X.getNonTypeTemplateArgumentType(); | |||
227 | if (!XType.isNull()) { | |||
228 | QualType YType = Y.getNonTypeTemplateArgumentType(); | |||
229 | if (YType.isNull() || !Context.hasSameType(XType, YType)) | |||
230 | return DeducedTemplateArgument(); | |||
231 | } | |||
232 | } | |||
233 | ||||
234 | switch (X.getKind()) { | |||
235 | case TemplateArgument::Null: | |||
236 | llvm_unreachable("Non-deduced template arguments handled above")::llvm::llvm_unreachable_internal("Non-deduced template arguments handled above" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 236); | |||
237 | ||||
238 | case TemplateArgument::Type: | |||
239 | // If two template type arguments have the same type, they're compatible. | |||
240 | if (Y.getKind() == TemplateArgument::Type && | |||
241 | Context.hasSameType(X.getAsType(), Y.getAsType())) | |||
242 | return X; | |||
243 | ||||
244 | // If one of the two arguments was deduced from an array bound, the other | |||
245 | // supersedes it. | |||
246 | if (X.wasDeducedFromArrayBound() != Y.wasDeducedFromArrayBound()) | |||
247 | return X.wasDeducedFromArrayBound() ? Y : X; | |||
248 | ||||
249 | // The arguments are not compatible. | |||
250 | return DeducedTemplateArgument(); | |||
251 | ||||
252 | case TemplateArgument::Integral: | |||
253 | // If we deduced a constant in one case and either a dependent expression or | |||
254 | // declaration in another case, keep the integral constant. | |||
255 | // If both are integral constants with the same value, keep that value. | |||
256 | if (Y.getKind() == TemplateArgument::Expression || | |||
257 | Y.getKind() == TemplateArgument::Declaration || | |||
258 | (Y.getKind() == TemplateArgument::Integral && | |||
259 | hasSameExtendedValue(X.getAsIntegral(), Y.getAsIntegral()))) | |||
260 | return X.wasDeducedFromArrayBound() ? Y : X; | |||
261 | ||||
262 | // All other combinations are incompatible. | |||
263 | return DeducedTemplateArgument(); | |||
264 | ||||
265 | case TemplateArgument::Template: | |||
266 | if (Y.getKind() == TemplateArgument::Template && | |||
267 | Context.hasSameTemplateName(X.getAsTemplate(), Y.getAsTemplate())) | |||
268 | return X; | |||
269 | ||||
270 | // All other combinations are incompatible. | |||
271 | return DeducedTemplateArgument(); | |||
272 | ||||
273 | case TemplateArgument::TemplateExpansion: | |||
274 | if (Y.getKind() == TemplateArgument::TemplateExpansion && | |||
275 | Context.hasSameTemplateName(X.getAsTemplateOrTemplatePattern(), | |||
276 | Y.getAsTemplateOrTemplatePattern())) | |||
277 | return X; | |||
278 | ||||
279 | // All other combinations are incompatible. | |||
280 | return DeducedTemplateArgument(); | |||
281 | ||||
282 | case TemplateArgument::Expression: { | |||
283 | if (Y.getKind() != TemplateArgument::Expression) | |||
284 | return checkDeducedTemplateArguments(Context, Y, X); | |||
285 | ||||
286 | // Compare the expressions for equality | |||
287 | llvm::FoldingSetNodeID ID1, ID2; | |||
288 | X.getAsExpr()->Profile(ID1, Context, true); | |||
289 | Y.getAsExpr()->Profile(ID2, Context, true); | |||
290 | if (ID1 == ID2) | |||
291 | return X.wasDeducedFromArrayBound() ? Y : X; | |||
292 | ||||
293 | // Differing dependent expressions are incompatible. | |||
294 | return DeducedTemplateArgument(); | |||
295 | } | |||
296 | ||||
297 | case TemplateArgument::Declaration: | |||
298 | assert(!X.wasDeducedFromArrayBound())(static_cast <bool> (!X.wasDeducedFromArrayBound()) ? void (0) : __assert_fail ("!X.wasDeducedFromArrayBound()", "clang/lib/Sema/SemaTemplateDeduction.cpp" , 298, __extension__ __PRETTY_FUNCTION__)); | |||
299 | ||||
300 | // If we deduced a declaration and a dependent expression, keep the | |||
301 | // declaration. | |||
302 | if (Y.getKind() == TemplateArgument::Expression) | |||
303 | return X; | |||
304 | ||||
305 | // If we deduced a declaration and an integral constant, keep the | |||
306 | // integral constant and whichever type did not come from an array | |||
307 | // bound. | |||
308 | if (Y.getKind() == TemplateArgument::Integral) { | |||
309 | if (Y.wasDeducedFromArrayBound()) | |||
310 | return TemplateArgument(Context, Y.getAsIntegral(), | |||
311 | X.getParamTypeForDecl()); | |||
312 | return Y; | |||
313 | } | |||
314 | ||||
315 | // If we deduced two declarations, make sure that they refer to the | |||
316 | // same declaration. | |||
317 | if (Y.getKind() == TemplateArgument::Declaration && | |||
318 | isSameDeclaration(X.getAsDecl(), Y.getAsDecl())) | |||
319 | return X; | |||
320 | ||||
321 | // All other combinations are incompatible. | |||
322 | return DeducedTemplateArgument(); | |||
323 | ||||
324 | case TemplateArgument::NullPtr: | |||
325 | // If we deduced a null pointer and a dependent expression, keep the | |||
326 | // null pointer. | |||
327 | if (Y.getKind() == TemplateArgument::Expression) | |||
328 | return X; | |||
329 | ||||
330 | // If we deduced a null pointer and an integral constant, keep the | |||
331 | // integral constant. | |||
332 | if (Y.getKind() == TemplateArgument::Integral) | |||
333 | return Y; | |||
334 | ||||
335 | // If we deduced two null pointers, they are the same. | |||
336 | if (Y.getKind() == TemplateArgument::NullPtr) | |||
337 | return X; | |||
338 | ||||
339 | // All other combinations are incompatible. | |||
340 | return DeducedTemplateArgument(); | |||
341 | ||||
342 | case TemplateArgument::Pack: { | |||
343 | if (Y.getKind() != TemplateArgument::Pack || | |||
344 | X.pack_size() != Y.pack_size()) | |||
345 | return DeducedTemplateArgument(); | |||
346 | ||||
347 | llvm::SmallVector<TemplateArgument, 8> NewPack; | |||
348 | for (TemplateArgument::pack_iterator XA = X.pack_begin(), | |||
349 | XAEnd = X.pack_end(), | |||
350 | YA = Y.pack_begin(); | |||
351 | XA != XAEnd; ++XA, ++YA) { | |||
352 | TemplateArgument Merged = checkDeducedTemplateArguments( | |||
353 | Context, DeducedTemplateArgument(*XA, X.wasDeducedFromArrayBound()), | |||
354 | DeducedTemplateArgument(*YA, Y.wasDeducedFromArrayBound())); | |||
355 | if (Merged.isNull() && !(XA->isNull() && YA->isNull())) | |||
356 | return DeducedTemplateArgument(); | |||
357 | NewPack.push_back(Merged); | |||
358 | } | |||
359 | ||||
360 | return DeducedTemplateArgument( | |||
361 | TemplateArgument::CreatePackCopy(Context, NewPack), | |||
362 | X.wasDeducedFromArrayBound() && Y.wasDeducedFromArrayBound()); | |||
363 | } | |||
364 | } | |||
365 | ||||
366 | llvm_unreachable("Invalid TemplateArgument Kind!")::llvm::llvm_unreachable_internal("Invalid TemplateArgument Kind!" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 366); | |||
367 | } | |||
368 | ||||
369 | /// Deduce the value of the given non-type template parameter | |||
370 | /// as the given deduced template argument. All non-type template parameter | |||
371 | /// deduction is funneled through here. | |||
372 | static Sema::TemplateDeductionResult DeduceNonTypeTemplateArgument( | |||
373 | Sema &S, TemplateParameterList *TemplateParams, | |||
374 | const NonTypeTemplateParmDecl *NTTP, const DeducedTemplateArgument &NewDeduced, | |||
375 | QualType ValueType, TemplateDeductionInfo &Info, | |||
376 | SmallVectorImpl<DeducedTemplateArgument> &Deduced) { | |||
377 | assert(NTTP->getDepth() == Info.getDeducedDepth() &&(static_cast <bool> (NTTP->getDepth() == Info.getDeducedDepth () && "deducing non-type template argument with wrong depth" ) ? void (0) : __assert_fail ("NTTP->getDepth() == Info.getDeducedDepth() && \"deducing non-type template argument with wrong depth\"" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 378, __extension__ __PRETTY_FUNCTION__)) | |||
378 | "deducing non-type template argument with wrong depth")(static_cast <bool> (NTTP->getDepth() == Info.getDeducedDepth () && "deducing non-type template argument with wrong depth" ) ? void (0) : __assert_fail ("NTTP->getDepth() == Info.getDeducedDepth() && \"deducing non-type template argument with wrong depth\"" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 378, __extension__ __PRETTY_FUNCTION__)); | |||
379 | ||||
380 | DeducedTemplateArgument Result = checkDeducedTemplateArguments( | |||
381 | S.Context, Deduced[NTTP->getIndex()], NewDeduced); | |||
382 | if (Result.isNull()) { | |||
383 | Info.Param = const_cast<NonTypeTemplateParmDecl*>(NTTP); | |||
384 | Info.FirstArg = Deduced[NTTP->getIndex()]; | |||
385 | Info.SecondArg = NewDeduced; | |||
386 | return Sema::TDK_Inconsistent; | |||
387 | } | |||
388 | ||||
389 | Deduced[NTTP->getIndex()] = Result; | |||
390 | if (!S.getLangOpts().CPlusPlus17) | |||
391 | return Sema::TDK_Success; | |||
392 | ||||
393 | if (NTTP->isExpandedParameterPack()) | |||
394 | // FIXME: We may still need to deduce parts of the type here! But we | |||
395 | // don't have any way to find which slice of the type to use, and the | |||
396 | // type stored on the NTTP itself is nonsense. Perhaps the type of an | |||
397 | // expanded NTTP should be a pack expansion type? | |||
398 | return Sema::TDK_Success; | |||
399 | ||||
400 | // Get the type of the parameter for deduction. If it's a (dependent) array | |||
401 | // or function type, we will not have decayed it yet, so do that now. | |||
402 | QualType ParamType = S.Context.getAdjustedParameterType(NTTP->getType()); | |||
403 | if (auto *Expansion = dyn_cast<PackExpansionType>(ParamType)) | |||
404 | ParamType = Expansion->getPattern(); | |||
405 | ||||
406 | // FIXME: It's not clear how deduction of a parameter of reference | |||
407 | // type from an argument (of non-reference type) should be performed. | |||
408 | // For now, we just remove reference types from both sides and let | |||
409 | // the final check for matching types sort out the mess. | |||
410 | ValueType = ValueType.getNonReferenceType(); | |||
411 | if (ParamType->isReferenceType()) | |||
412 | ParamType = ParamType.getNonReferenceType(); | |||
413 | else | |||
414 | // Top-level cv-qualifiers are irrelevant for a non-reference type. | |||
415 | ValueType = ValueType.getUnqualifiedType(); | |||
416 | ||||
417 | return DeduceTemplateArgumentsByTypeMatch( | |||
418 | S, TemplateParams, ParamType, ValueType, Info, Deduced, | |||
419 | TDF_SkipNonDependent, /*PartialOrdering=*/false, | |||
420 | /*ArrayBound=*/NewDeduced.wasDeducedFromArrayBound()); | |||
421 | } | |||
422 | ||||
423 | /// Deduce the value of the given non-type template parameter | |||
424 | /// from the given integral constant. | |||
425 | static Sema::TemplateDeductionResult DeduceNonTypeTemplateArgument( | |||
426 | Sema &S, TemplateParameterList *TemplateParams, | |||
427 | const NonTypeTemplateParmDecl *NTTP, const llvm::APSInt &Value, | |||
428 | QualType ValueType, bool DeducedFromArrayBound, TemplateDeductionInfo &Info, | |||
429 | SmallVectorImpl<DeducedTemplateArgument> &Deduced) { | |||
430 | return DeduceNonTypeTemplateArgument( | |||
431 | S, TemplateParams, NTTP, | |||
432 | DeducedTemplateArgument(S.Context, Value, ValueType, | |||
433 | DeducedFromArrayBound), | |||
434 | ValueType, Info, Deduced); | |||
435 | } | |||
436 | ||||
437 | /// Deduce the value of the given non-type template parameter | |||
438 | /// from the given null pointer template argument type. | |||
439 | static Sema::TemplateDeductionResult DeduceNullPtrTemplateArgument( | |||
440 | Sema &S, TemplateParameterList *TemplateParams, | |||
441 | const NonTypeTemplateParmDecl *NTTP, QualType NullPtrType, | |||
442 | TemplateDeductionInfo &Info, | |||
443 | SmallVectorImpl<DeducedTemplateArgument> &Deduced) { | |||
444 | Expr *Value = S.ImpCastExprToType( | |||
445 | new (S.Context) CXXNullPtrLiteralExpr(S.Context.NullPtrTy, | |||
446 | NTTP->getLocation()), | |||
447 | NullPtrType, | |||
448 | NullPtrType->isMemberPointerType() ? CK_NullToMemberPointer | |||
449 | : CK_NullToPointer) | |||
450 | .get(); | |||
451 | return DeduceNonTypeTemplateArgument(S, TemplateParams, NTTP, | |||
452 | DeducedTemplateArgument(Value), | |||
453 | Value->getType(), Info, Deduced); | |||
454 | } | |||
455 | ||||
456 | /// Deduce the value of the given non-type template parameter | |||
457 | /// from the given type- or value-dependent expression. | |||
458 | /// | |||
459 | /// \returns true if deduction succeeded, false otherwise. | |||
460 | static Sema::TemplateDeductionResult DeduceNonTypeTemplateArgument( | |||
461 | Sema &S, TemplateParameterList *TemplateParams, | |||
462 | const NonTypeTemplateParmDecl *NTTP, Expr *Value, TemplateDeductionInfo &Info, | |||
463 | SmallVectorImpl<DeducedTemplateArgument> &Deduced) { | |||
464 | return DeduceNonTypeTemplateArgument(S, TemplateParams, NTTP, | |||
465 | DeducedTemplateArgument(Value), | |||
466 | Value->getType(), Info, Deduced); | |||
467 | } | |||
468 | ||||
469 | /// Deduce the value of the given non-type template parameter | |||
470 | /// from the given declaration. | |||
471 | /// | |||
472 | /// \returns true if deduction succeeded, false otherwise. | |||
473 | static Sema::TemplateDeductionResult DeduceNonTypeTemplateArgument( | |||
474 | Sema &S, TemplateParameterList *TemplateParams, | |||
475 | const NonTypeTemplateParmDecl *NTTP, ValueDecl *D, QualType T, | |||
476 | TemplateDeductionInfo &Info, | |||
477 | SmallVectorImpl<DeducedTemplateArgument> &Deduced) { | |||
478 | D = D ? cast<ValueDecl>(D->getCanonicalDecl()) : nullptr; | |||
479 | TemplateArgument New(D, T); | |||
480 | return DeduceNonTypeTemplateArgument( | |||
481 | S, TemplateParams, NTTP, DeducedTemplateArgument(New), T, Info, Deduced); | |||
482 | } | |||
483 | ||||
484 | static Sema::TemplateDeductionResult | |||
485 | DeduceTemplateArguments(Sema &S, | |||
486 | TemplateParameterList *TemplateParams, | |||
487 | TemplateName Param, | |||
488 | TemplateName Arg, | |||
489 | TemplateDeductionInfo &Info, | |||
490 | SmallVectorImpl<DeducedTemplateArgument> &Deduced) { | |||
491 | TemplateDecl *ParamDecl = Param.getAsTemplateDecl(); | |||
492 | if (!ParamDecl) { | |||
493 | // The parameter type is dependent and is not a template template parameter, | |||
494 | // so there is nothing that we can deduce. | |||
495 | return Sema::TDK_Success; | |||
496 | } | |||
497 | ||||
498 | if (TemplateTemplateParmDecl *TempParam | |||
499 | = dyn_cast<TemplateTemplateParmDecl>(ParamDecl)) { | |||
500 | // If we're not deducing at this depth, there's nothing to deduce. | |||
501 | if (TempParam->getDepth() != Info.getDeducedDepth()) | |||
502 | return Sema::TDK_Success; | |||
503 | ||||
504 | DeducedTemplateArgument NewDeduced(S.Context.getCanonicalTemplateName(Arg)); | |||
505 | DeducedTemplateArgument Result = checkDeducedTemplateArguments(S.Context, | |||
506 | Deduced[TempParam->getIndex()], | |||
507 | NewDeduced); | |||
508 | if (Result.isNull()) { | |||
509 | Info.Param = TempParam; | |||
510 | Info.FirstArg = Deduced[TempParam->getIndex()]; | |||
511 | Info.SecondArg = NewDeduced; | |||
512 | return Sema::TDK_Inconsistent; | |||
513 | } | |||
514 | ||||
515 | Deduced[TempParam->getIndex()] = Result; | |||
516 | return Sema::TDK_Success; | |||
517 | } | |||
518 | ||||
519 | // Verify that the two template names are equivalent. | |||
520 | if (S.Context.hasSameTemplateName(Param, Arg)) | |||
521 | return Sema::TDK_Success; | |||
522 | ||||
523 | // Mismatch of non-dependent template parameter to argument. | |||
524 | Info.FirstArg = TemplateArgument(Param); | |||
525 | Info.SecondArg = TemplateArgument(Arg); | |||
526 | return Sema::TDK_NonDeducedMismatch; | |||
527 | } | |||
528 | ||||
529 | /// Deduce the template arguments by comparing the template parameter | |||
530 | /// type (which is a template-id) with the template argument type. | |||
531 | /// | |||
532 | /// \param S the Sema | |||
533 | /// | |||
534 | /// \param TemplateParams the template parameters that we are deducing | |||
535 | /// | |||
536 | /// \param P the parameter type | |||
537 | /// | |||
538 | /// \param A the argument type | |||
539 | /// | |||
540 | /// \param Info information about the template argument deduction itself | |||
541 | /// | |||
542 | /// \param Deduced the deduced template arguments | |||
543 | /// | |||
544 | /// \returns the result of template argument deduction so far. Note that a | |||
545 | /// "success" result means that template argument deduction has not yet failed, | |||
546 | /// but it may still fail, later, for other reasons. | |||
547 | static Sema::TemplateDeductionResult | |||
548 | DeduceTemplateSpecArguments(Sema &S, TemplateParameterList *TemplateParams, | |||
549 | const QualType P, QualType A, | |||
550 | TemplateDeductionInfo &Info, | |||
551 | SmallVectorImpl<DeducedTemplateArgument> &Deduced) { | |||
552 | QualType UP = P; | |||
553 | if (const auto *IP = P->getAs<InjectedClassNameType>()) | |||
554 | UP = IP->getInjectedSpecializationType(); | |||
555 | // FIXME: Try to preserve type sugar here, which is hard | |||
556 | // because of the unresolved template arguments. | |||
557 | const auto *TP = UP.getCanonicalType()->castAs<TemplateSpecializationType>(); | |||
558 | ArrayRef<TemplateArgument> PResolved = TP->template_arguments(); | |||
559 | ||||
560 | QualType UA = A; | |||
561 | // Treat an injected-class-name as its underlying template-id. | |||
562 | if (const auto *Injected = A->getAs<InjectedClassNameType>()) | |||
563 | UA = Injected->getInjectedSpecializationType(); | |||
564 | ||||
565 | // Check whether the template argument is a dependent template-id. | |||
566 | // FIXME: Should not lose sugar here. | |||
567 | if (const auto *SA = | |||
568 | dyn_cast<TemplateSpecializationType>(UA.getCanonicalType())) { | |||
569 | // Perform template argument deduction for the template name. | |||
570 | if (auto Result = | |||
571 | DeduceTemplateArguments(S, TemplateParams, TP->getTemplateName(), | |||
572 | SA->getTemplateName(), Info, Deduced)) | |||
573 | return Result; | |||
574 | // Perform template argument deduction on each template | |||
575 | // argument. Ignore any missing/extra arguments, since they could be | |||
576 | // filled in by default arguments. | |||
577 | return DeduceTemplateArguments(S, TemplateParams, PResolved, | |||
578 | SA->template_arguments(), Info, Deduced, | |||
579 | /*NumberOfArgumentsMustMatch=*/false); | |||
580 | } | |||
581 | ||||
582 | // If the argument type is a class template specialization, we | |||
583 | // perform template argument deduction using its template | |||
584 | // arguments. | |||
585 | const auto *RA = UA->getAs<RecordType>(); | |||
586 | const auto *SA = | |||
587 | RA ? dyn_cast<ClassTemplateSpecializationDecl>(RA->getDecl()) : nullptr; | |||
588 | if (!SA) { | |||
589 | Info.FirstArg = TemplateArgument(P); | |||
590 | Info.SecondArg = TemplateArgument(A); | |||
591 | return Sema::TDK_NonDeducedMismatch; | |||
592 | } | |||
593 | ||||
594 | // Perform template argument deduction for the template name. | |||
595 | if (auto Result = DeduceTemplateArguments( | |||
596 | S, TemplateParams, TP->getTemplateName(), | |||
597 | TemplateName(SA->getSpecializedTemplate()), Info, Deduced)) | |||
598 | return Result; | |||
599 | ||||
600 | // Perform template argument deduction for the template arguments. | |||
601 | return DeduceTemplateArguments(S, TemplateParams, PResolved, | |||
602 | SA->getTemplateArgs().asArray(), Info, Deduced, | |||
603 | /*NumberOfArgumentsMustMatch=*/true); | |||
604 | } | |||
605 | ||||
606 | static bool IsPossiblyOpaquelyQualifiedTypeInternal(const Type *T) { | |||
607 | assert(T->isCanonicalUnqualified())(static_cast <bool> (T->isCanonicalUnqualified()) ? void (0) : __assert_fail ("T->isCanonicalUnqualified()", "clang/lib/Sema/SemaTemplateDeduction.cpp" , 607, __extension__ __PRETTY_FUNCTION__)); | |||
608 | ||||
609 | switch (T->getTypeClass()) { | |||
610 | case Type::TypeOfExpr: | |||
611 | case Type::TypeOf: | |||
612 | case Type::DependentName: | |||
613 | case Type::Decltype: | |||
614 | case Type::UnresolvedUsing: | |||
615 | case Type::TemplateTypeParm: | |||
616 | return true; | |||
617 | ||||
618 | case Type::ConstantArray: | |||
619 | case Type::IncompleteArray: | |||
620 | case Type::VariableArray: | |||
621 | case Type::DependentSizedArray: | |||
622 | return IsPossiblyOpaquelyQualifiedTypeInternal( | |||
623 | cast<ArrayType>(T)->getElementType().getTypePtr()); | |||
624 | ||||
625 | default: | |||
626 | return false; | |||
627 | } | |||
628 | } | |||
629 | ||||
630 | /// Determines whether the given type is an opaque type that | |||
631 | /// might be more qualified when instantiated. | |||
632 | static bool IsPossiblyOpaquelyQualifiedType(QualType T) { | |||
633 | return IsPossiblyOpaquelyQualifiedTypeInternal( | |||
634 | T->getCanonicalTypeInternal().getTypePtr()); | |||
635 | } | |||
636 | ||||
637 | /// Helper function to build a TemplateParameter when we don't | |||
638 | /// know its type statically. | |||
639 | static TemplateParameter makeTemplateParameter(Decl *D) { | |||
640 | if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(D)) | |||
641 | return TemplateParameter(TTP); | |||
642 | if (NonTypeTemplateParmDecl *NTTP = dyn_cast<NonTypeTemplateParmDecl>(D)) | |||
643 | return TemplateParameter(NTTP); | |||
644 | ||||
645 | return TemplateParameter(cast<TemplateTemplateParmDecl>(D)); | |||
646 | } | |||
647 | ||||
648 | /// A pack that we're currently deducing. | |||
649 | struct clang::DeducedPack { | |||
650 | // The index of the pack. | |||
651 | unsigned Index; | |||
652 | ||||
653 | // The old value of the pack before we started deducing it. | |||
654 | DeducedTemplateArgument Saved; | |||
655 | ||||
656 | // A deferred value of this pack from an inner deduction, that couldn't be | |||
657 | // deduced because this deduction hadn't happened yet. | |||
658 | DeducedTemplateArgument DeferredDeduction; | |||
659 | ||||
660 | // The new value of the pack. | |||
661 | SmallVector<DeducedTemplateArgument, 4> New; | |||
662 | ||||
663 | // The outer deduction for this pack, if any. | |||
664 | DeducedPack *Outer = nullptr; | |||
665 | ||||
666 | DeducedPack(unsigned Index) : Index(Index) {} | |||
667 | }; | |||
668 | ||||
669 | namespace { | |||
670 | ||||
671 | /// A scope in which we're performing pack deduction. | |||
672 | class PackDeductionScope { | |||
673 | public: | |||
674 | /// Prepare to deduce the packs named within Pattern. | |||
675 | PackDeductionScope(Sema &S, TemplateParameterList *TemplateParams, | |||
676 | SmallVectorImpl<DeducedTemplateArgument> &Deduced, | |||
677 | TemplateDeductionInfo &Info, TemplateArgument Pattern) | |||
678 | : S(S), TemplateParams(TemplateParams), Deduced(Deduced), Info(Info) { | |||
679 | unsigned NumNamedPacks = addPacks(Pattern); | |||
680 | finishConstruction(NumNamedPacks); | |||
681 | } | |||
682 | ||||
683 | /// Prepare to directly deduce arguments of the parameter with index \p Index. | |||
684 | PackDeductionScope(Sema &S, TemplateParameterList *TemplateParams, | |||
685 | SmallVectorImpl<DeducedTemplateArgument> &Deduced, | |||
686 | TemplateDeductionInfo &Info, unsigned Index) | |||
687 | : S(S), TemplateParams(TemplateParams), Deduced(Deduced), Info(Info) { | |||
688 | addPack(Index); | |||
689 | finishConstruction(1); | |||
690 | } | |||
691 | ||||
692 | private: | |||
693 | void addPack(unsigned Index) { | |||
694 | // Save the deduced template argument for the parameter pack expanded | |||
695 | // by this pack expansion, then clear out the deduction. | |||
696 | DeducedPack Pack(Index); | |||
697 | Pack.Saved = Deduced[Index]; | |||
698 | Deduced[Index] = TemplateArgument(); | |||
699 | ||||
700 | // FIXME: What if we encounter multiple packs with different numbers of | |||
701 | // pre-expanded expansions? (This should already have been diagnosed | |||
702 | // during substitution.) | |||
703 | if (Optional<unsigned> ExpandedPackExpansions = | |||
704 | getExpandedPackSize(TemplateParams->getParam(Index))) | |||
705 | FixedNumExpansions = ExpandedPackExpansions; | |||
706 | ||||
707 | Packs.push_back(Pack); | |||
708 | } | |||
709 | ||||
710 | unsigned addPacks(TemplateArgument Pattern) { | |||
711 | // Compute the set of template parameter indices that correspond to | |||
712 | // parameter packs expanded by the pack expansion. | |||
713 | llvm::SmallBitVector SawIndices(TemplateParams->size()); | |||
714 | llvm::SmallVector<TemplateArgument, 4> ExtraDeductions; | |||
715 | ||||
716 | auto AddPack = [&](unsigned Index) { | |||
717 | if (SawIndices[Index]) | |||
718 | return; | |||
719 | SawIndices[Index] = true; | |||
720 | addPack(Index); | |||
721 | ||||
722 | // Deducing a parameter pack that is a pack expansion also constrains the | |||
723 | // packs appearing in that parameter to have the same deduced arity. Also, | |||
724 | // in C++17 onwards, deducing a non-type template parameter deduces its | |||
725 | // type, so we need to collect the pending deduced values for those packs. | |||
726 | if (auto *NTTP = dyn_cast<NonTypeTemplateParmDecl>( | |||
727 | TemplateParams->getParam(Index))) { | |||
728 | if (!NTTP->isExpandedParameterPack()) | |||
729 | if (auto *Expansion = dyn_cast<PackExpansionType>(NTTP->getType())) | |||
730 | ExtraDeductions.push_back(Expansion->getPattern()); | |||
731 | } | |||
732 | // FIXME: Also collect the unexpanded packs in any type and template | |||
733 | // parameter packs that are pack expansions. | |||
734 | }; | |||
735 | ||||
736 | auto Collect = [&](TemplateArgument Pattern) { | |||
737 | SmallVector<UnexpandedParameterPack, 2> Unexpanded; | |||
738 | S.collectUnexpandedParameterPacks(Pattern, Unexpanded); | |||
739 | for (unsigned I = 0, N = Unexpanded.size(); I != N; ++I) { | |||
740 | unsigned Depth, Index; | |||
741 | std::tie(Depth, Index) = getDepthAndIndex(Unexpanded[I]); | |||
742 | if (Depth == Info.getDeducedDepth()) | |||
743 | AddPack(Index); | |||
744 | } | |||
745 | }; | |||
746 | ||||
747 | // Look for unexpanded packs in the pattern. | |||
748 | Collect(Pattern); | |||
749 | assert(!Packs.empty() && "Pack expansion without unexpanded packs?")(static_cast <bool> (!Packs.empty() && "Pack expansion without unexpanded packs?" ) ? void (0) : __assert_fail ("!Packs.empty() && \"Pack expansion without unexpanded packs?\"" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 749, __extension__ __PRETTY_FUNCTION__)); | |||
750 | ||||
751 | unsigned NumNamedPacks = Packs.size(); | |||
752 | ||||
753 | // Also look for unexpanded packs that are indirectly deduced by deducing | |||
754 | // the sizes of the packs in this pattern. | |||
755 | while (!ExtraDeductions.empty()) | |||
756 | Collect(ExtraDeductions.pop_back_val()); | |||
757 | ||||
758 | return NumNamedPacks; | |||
759 | } | |||
760 | ||||
761 | void finishConstruction(unsigned NumNamedPacks) { | |||
762 | // Dig out the partially-substituted pack, if there is one. | |||
763 | const TemplateArgument *PartialPackArgs = nullptr; | |||
764 | unsigned NumPartialPackArgs = 0; | |||
765 | std::pair<unsigned, unsigned> PartialPackDepthIndex(-1u, -1u); | |||
766 | if (auto *Scope = S.CurrentInstantiationScope) | |||
767 | if (auto *Partial = Scope->getPartiallySubstitutedPack( | |||
768 | &PartialPackArgs, &NumPartialPackArgs)) | |||
769 | PartialPackDepthIndex = getDepthAndIndex(Partial); | |||
770 | ||||
771 | // This pack expansion will have been partially or fully expanded if | |||
772 | // it only names explicitly-specified parameter packs (including the | |||
773 | // partially-substituted one, if any). | |||
774 | bool IsExpanded = true; | |||
775 | for (unsigned I = 0; I != NumNamedPacks; ++I) { | |||
776 | if (Packs[I].Index >= Info.getNumExplicitArgs()) { | |||
777 | IsExpanded = false; | |||
778 | IsPartiallyExpanded = false; | |||
779 | break; | |||
780 | } | |||
781 | if (PartialPackDepthIndex == | |||
782 | std::make_pair(Info.getDeducedDepth(), Packs[I].Index)) { | |||
783 | IsPartiallyExpanded = true; | |||
784 | } | |||
785 | } | |||
786 | ||||
787 | // Skip over the pack elements that were expanded into separate arguments. | |||
788 | // If we partially expanded, this is the number of partial arguments. | |||
789 | if (IsPartiallyExpanded) | |||
790 | PackElements += NumPartialPackArgs; | |||
791 | else if (IsExpanded) | |||
792 | PackElements += *FixedNumExpansions; | |||
793 | ||||
794 | for (auto &Pack : Packs) { | |||
795 | if (Info.PendingDeducedPacks.size() > Pack.Index) | |||
796 | Pack.Outer = Info.PendingDeducedPacks[Pack.Index]; | |||
797 | else | |||
798 | Info.PendingDeducedPacks.resize(Pack.Index + 1); | |||
799 | Info.PendingDeducedPacks[Pack.Index] = &Pack; | |||
800 | ||||
801 | if (PartialPackDepthIndex == | |||
802 | std::make_pair(Info.getDeducedDepth(), Pack.Index)) { | |||
803 | Pack.New.append(PartialPackArgs, PartialPackArgs + NumPartialPackArgs); | |||
804 | // We pre-populate the deduced value of the partially-substituted | |||
805 | // pack with the specified value. This is not entirely correct: the | |||
806 | // value is supposed to have been substituted, not deduced, but the | |||
807 | // cases where this is observable require an exact type match anyway. | |||
808 | // | |||
809 | // FIXME: If we could represent a "depth i, index j, pack elem k" | |||
810 | // parameter, we could substitute the partially-substituted pack | |||
811 | // everywhere and avoid this. | |||
812 | if (!IsPartiallyExpanded) | |||
813 | Deduced[Pack.Index] = Pack.New[PackElements]; | |||
814 | } | |||
815 | } | |||
816 | } | |||
817 | ||||
818 | public: | |||
819 | ~PackDeductionScope() { | |||
820 | for (auto &Pack : Packs) | |||
821 | Info.PendingDeducedPacks[Pack.Index] = Pack.Outer; | |||
822 | } | |||
823 | ||||
824 | /// Determine whether this pack has already been partially expanded into a | |||
825 | /// sequence of (prior) function parameters / template arguments. | |||
826 | bool isPartiallyExpanded() { return IsPartiallyExpanded; } | |||
827 | ||||
828 | /// Determine whether this pack expansion scope has a known, fixed arity. | |||
829 | /// This happens if it involves a pack from an outer template that has | |||
830 | /// (notionally) already been expanded. | |||
831 | bool hasFixedArity() { return FixedNumExpansions.hasValue(); } | |||
832 | ||||
833 | /// Determine whether the next element of the argument is still part of this | |||
834 | /// pack. This is the case unless the pack is already expanded to a fixed | |||
835 | /// length. | |||
836 | bool hasNextElement() { | |||
837 | return !FixedNumExpansions || *FixedNumExpansions > PackElements; | |||
838 | } | |||
839 | ||||
840 | /// Move to deducing the next element in each pack that is being deduced. | |||
841 | void nextPackElement() { | |||
842 | // Capture the deduced template arguments for each parameter pack expanded | |||
843 | // by this pack expansion, add them to the list of arguments we've deduced | |||
844 | // for that pack, then clear out the deduced argument. | |||
845 | for (auto &Pack : Packs) { | |||
846 | DeducedTemplateArgument &DeducedArg = Deduced[Pack.Index]; | |||
847 | if (!Pack.New.empty() || !DeducedArg.isNull()) { | |||
848 | while (Pack.New.size() < PackElements) | |||
849 | Pack.New.push_back(DeducedTemplateArgument()); | |||
850 | if (Pack.New.size() == PackElements) | |||
851 | Pack.New.push_back(DeducedArg); | |||
852 | else | |||
853 | Pack.New[PackElements] = DeducedArg; | |||
854 | DeducedArg = Pack.New.size() > PackElements + 1 | |||
855 | ? Pack.New[PackElements + 1] | |||
856 | : DeducedTemplateArgument(); | |||
857 | } | |||
858 | } | |||
859 | ++PackElements; | |||
860 | } | |||
861 | ||||
862 | /// Finish template argument deduction for a set of argument packs, | |||
863 | /// producing the argument packs and checking for consistency with prior | |||
864 | /// deductions. | |||
865 | Sema::TemplateDeductionResult finish() { | |||
866 | // Build argument packs for each of the parameter packs expanded by this | |||
867 | // pack expansion. | |||
868 | for (auto &Pack : Packs) { | |||
869 | // Put back the old value for this pack. | |||
870 | Deduced[Pack.Index] = Pack.Saved; | |||
871 | ||||
872 | // Always make sure the size of this pack is correct, even if we didn't | |||
873 | // deduce any values for it. | |||
874 | // | |||
875 | // FIXME: This isn't required by the normative wording, but substitution | |||
876 | // and post-substitution checking will always fail if the arity of any | |||
877 | // pack is not equal to the number of elements we processed. (Either that | |||
878 | // or something else has gone *very* wrong.) We're permitted to skip any | |||
879 | // hard errors from those follow-on steps by the intent (but not the | |||
880 | // wording) of C++ [temp.inst]p8: | |||
881 | // | |||
882 | // If the function selected by overload resolution can be determined | |||
883 | // without instantiating a class template definition, it is unspecified | |||
884 | // whether that instantiation actually takes place | |||
885 | Pack.New.resize(PackElements); | |||
886 | ||||
887 | // Build or find a new value for this pack. | |||
888 | DeducedTemplateArgument NewPack; | |||
889 | if (Pack.New.empty()) { | |||
890 | // If we deduced an empty argument pack, create it now. | |||
891 | NewPack = DeducedTemplateArgument(TemplateArgument::getEmptyPack()); | |||
892 | } else { | |||
893 | TemplateArgument *ArgumentPack = | |||
894 | new (S.Context) TemplateArgument[Pack.New.size()]; | |||
895 | std::copy(Pack.New.begin(), Pack.New.end(), ArgumentPack); | |||
896 | NewPack = DeducedTemplateArgument( | |||
897 | TemplateArgument(llvm::makeArrayRef(ArgumentPack, Pack.New.size())), | |||
898 | // FIXME: This is wrong, it's possible that some pack elements are | |||
899 | // deduced from an array bound and others are not: | |||
900 | // template<typename ...T, T ...V> void g(const T (&...p)[V]); | |||
901 | // g({1, 2, 3}, {{}, {}}); | |||
902 | // ... should deduce T = {int, size_t (from array bound)}. | |||
903 | Pack.New[0].wasDeducedFromArrayBound()); | |||
904 | } | |||
905 | ||||
906 | // Pick where we're going to put the merged pack. | |||
907 | DeducedTemplateArgument *Loc; | |||
908 | if (Pack.Outer) { | |||
909 | if (Pack.Outer->DeferredDeduction.isNull()) { | |||
910 | // Defer checking this pack until we have a complete pack to compare | |||
911 | // it against. | |||
912 | Pack.Outer->DeferredDeduction = NewPack; | |||
913 | continue; | |||
914 | } | |||
915 | Loc = &Pack.Outer->DeferredDeduction; | |||
916 | } else { | |||
917 | Loc = &Deduced[Pack.Index]; | |||
918 | } | |||
919 | ||||
920 | // Check the new pack matches any previous value. | |||
921 | DeducedTemplateArgument OldPack = *Loc; | |||
922 | DeducedTemplateArgument Result = | |||
923 | checkDeducedTemplateArguments(S.Context, OldPack, NewPack); | |||
924 | ||||
925 | // If we deferred a deduction of this pack, check that one now too. | |||
926 | if (!Result.isNull() && !Pack.DeferredDeduction.isNull()) { | |||
927 | OldPack = Result; | |||
928 | NewPack = Pack.DeferredDeduction; | |||
929 | Result = checkDeducedTemplateArguments(S.Context, OldPack, NewPack); | |||
930 | } | |||
931 | ||||
932 | NamedDecl *Param = TemplateParams->getParam(Pack.Index); | |||
933 | if (Result.isNull()) { | |||
934 | Info.Param = makeTemplateParameter(Param); | |||
935 | Info.FirstArg = OldPack; | |||
936 | Info.SecondArg = NewPack; | |||
937 | return Sema::TDK_Inconsistent; | |||
938 | } | |||
939 | ||||
940 | // If we have a pre-expanded pack and we didn't deduce enough elements | |||
941 | // for it, fail deduction. | |||
942 | if (Optional<unsigned> Expansions = getExpandedPackSize(Param)) { | |||
943 | if (*Expansions != PackElements) { | |||
944 | Info.Param = makeTemplateParameter(Param); | |||
945 | Info.FirstArg = Result; | |||
946 | return Sema::TDK_IncompletePack; | |||
947 | } | |||
948 | } | |||
949 | ||||
950 | *Loc = Result; | |||
951 | } | |||
952 | ||||
953 | return Sema::TDK_Success; | |||
954 | } | |||
955 | ||||
956 | private: | |||
957 | Sema &S; | |||
958 | TemplateParameterList *TemplateParams; | |||
959 | SmallVectorImpl<DeducedTemplateArgument> &Deduced; | |||
960 | TemplateDeductionInfo &Info; | |||
961 | unsigned PackElements = 0; | |||
962 | bool IsPartiallyExpanded = false; | |||
963 | /// The number of expansions, if we have a fully-expanded pack in this scope. | |||
964 | Optional<unsigned> FixedNumExpansions; | |||
965 | ||||
966 | SmallVector<DeducedPack, 2> Packs; | |||
967 | }; | |||
968 | ||||
969 | } // namespace | |||
970 | ||||
971 | /// Deduce the template arguments by comparing the list of parameter | |||
972 | /// types to the list of argument types, as in the parameter-type-lists of | |||
973 | /// function types (C++ [temp.deduct.type]p10). | |||
974 | /// | |||
975 | /// \param S The semantic analysis object within which we are deducing | |||
976 | /// | |||
977 | /// \param TemplateParams The template parameters that we are deducing | |||
978 | /// | |||
979 | /// \param Params The list of parameter types | |||
980 | /// | |||
981 | /// \param NumParams The number of types in \c Params | |||
982 | /// | |||
983 | /// \param Args The list of argument types | |||
984 | /// | |||
985 | /// \param NumArgs The number of types in \c Args | |||
986 | /// | |||
987 | /// \param Info information about the template argument deduction itself | |||
988 | /// | |||
989 | /// \param Deduced the deduced template arguments | |||
990 | /// | |||
991 | /// \param TDF bitwise OR of the TemplateDeductionFlags bits that describe | |||
992 | /// how template argument deduction is performed. | |||
993 | /// | |||
994 | /// \param PartialOrdering If true, we are performing template argument | |||
995 | /// deduction for during partial ordering for a call | |||
996 | /// (C++0x [temp.deduct.partial]). | |||
997 | /// | |||
998 | /// \returns the result of template argument deduction so far. Note that a | |||
999 | /// "success" result means that template argument deduction has not yet failed, | |||
1000 | /// but it may still fail, later, for other reasons. | |||
1001 | static Sema::TemplateDeductionResult | |||
1002 | DeduceTemplateArguments(Sema &S, | |||
1003 | TemplateParameterList *TemplateParams, | |||
1004 | const QualType *Params, unsigned NumParams, | |||
1005 | const QualType *Args, unsigned NumArgs, | |||
1006 | TemplateDeductionInfo &Info, | |||
1007 | SmallVectorImpl<DeducedTemplateArgument> &Deduced, | |||
1008 | unsigned TDF, | |||
1009 | bool PartialOrdering = false) { | |||
1010 | // C++0x [temp.deduct.type]p10: | |||
1011 | // Similarly, if P has a form that contains (T), then each parameter type | |||
1012 | // Pi of the respective parameter-type- list of P is compared with the | |||
1013 | // corresponding parameter type Ai of the corresponding parameter-type-list | |||
1014 | // of A. [...] | |||
1015 | unsigned ArgIdx = 0, ParamIdx = 0; | |||
1016 | for (; ParamIdx != NumParams; ++ParamIdx) { | |||
1017 | // Check argument types. | |||
1018 | const PackExpansionType *Expansion | |||
1019 | = dyn_cast<PackExpansionType>(Params[ParamIdx]); | |||
1020 | if (!Expansion) { | |||
1021 | // Simple case: compare the parameter and argument types at this point. | |||
1022 | ||||
1023 | // Make sure we have an argument. | |||
1024 | if (ArgIdx >= NumArgs) | |||
1025 | return Sema::TDK_MiscellaneousDeductionFailure; | |||
1026 | ||||
1027 | if (isa<PackExpansionType>(Args[ArgIdx])) { | |||
1028 | // C++0x [temp.deduct.type]p22: | |||
1029 | // If the original function parameter associated with A is a function | |||
1030 | // parameter pack and the function parameter associated with P is not | |||
1031 | // a function parameter pack, then template argument deduction fails. | |||
1032 | return Sema::TDK_MiscellaneousDeductionFailure; | |||
1033 | } | |||
1034 | ||||
1035 | if (Sema::TemplateDeductionResult Result = | |||
1036 | DeduceTemplateArgumentsByTypeMatch( | |||
1037 | S, TemplateParams, Params[ParamIdx].getUnqualifiedType(), | |||
1038 | Args[ArgIdx].getUnqualifiedType(), Info, Deduced, TDF, | |||
1039 | PartialOrdering, | |||
1040 | /*DeducedFromArrayBound=*/false)) | |||
1041 | return Result; | |||
1042 | ||||
1043 | ++ArgIdx; | |||
1044 | continue; | |||
1045 | } | |||
1046 | ||||
1047 | // C++0x [temp.deduct.type]p10: | |||
1048 | // If the parameter-declaration corresponding to Pi is a function | |||
1049 | // parameter pack, then the type of its declarator- id is compared with | |||
1050 | // each remaining parameter type in the parameter-type-list of A. Each | |||
1051 | // comparison deduces template arguments for subsequent positions in the | |||
1052 | // template parameter packs expanded by the function parameter pack. | |||
1053 | ||||
1054 | QualType Pattern = Expansion->getPattern(); | |||
1055 | PackDeductionScope PackScope(S, TemplateParams, Deduced, Info, Pattern); | |||
1056 | ||||
1057 | // A pack scope with fixed arity is not really a pack any more, so is not | |||
1058 | // a non-deduced context. | |||
1059 | if (ParamIdx + 1 == NumParams || PackScope.hasFixedArity()) { | |||
1060 | for (; ArgIdx < NumArgs && PackScope.hasNextElement(); ++ArgIdx) { | |||
1061 | // Deduce template arguments from the pattern. | |||
1062 | if (Sema::TemplateDeductionResult Result = | |||
1063 | DeduceTemplateArgumentsByTypeMatch( | |||
1064 | S, TemplateParams, Pattern.getUnqualifiedType(), | |||
1065 | Args[ArgIdx].getUnqualifiedType(), Info, Deduced, TDF, | |||
1066 | PartialOrdering, /*DeducedFromArrayBound=*/false)) | |||
1067 | return Result; | |||
1068 | ||||
1069 | PackScope.nextPackElement(); | |||
1070 | } | |||
1071 | } else { | |||
1072 | // C++0x [temp.deduct.type]p5: | |||
1073 | // The non-deduced contexts are: | |||
1074 | // - A function parameter pack that does not occur at the end of the | |||
1075 | // parameter-declaration-clause. | |||
1076 | // | |||
1077 | // FIXME: There is no wording to say what we should do in this case. We | |||
1078 | // choose to resolve this by applying the same rule that is applied for a | |||
1079 | // function call: that is, deduce all contained packs to their | |||
1080 | // explicitly-specified values (or to <> if there is no such value). | |||
1081 | // | |||
1082 | // This is seemingly-arbitrarily different from the case of a template-id | |||
1083 | // with a non-trailing pack-expansion in its arguments, which renders the | |||
1084 | // entire template-argument-list a non-deduced context. | |||
1085 | ||||
1086 | // If the parameter type contains an explicitly-specified pack that we | |||
1087 | // could not expand, skip the number of parameters notionally created | |||
1088 | // by the expansion. | |||
1089 | Optional<unsigned> NumExpansions = Expansion->getNumExpansions(); | |||
1090 | if (NumExpansions && !PackScope.isPartiallyExpanded()) { | |||
1091 | for (unsigned I = 0; I != *NumExpansions && ArgIdx < NumArgs; | |||
1092 | ++I, ++ArgIdx) | |||
1093 | PackScope.nextPackElement(); | |||
1094 | } | |||
1095 | } | |||
1096 | ||||
1097 | // Build argument packs for each of the parameter packs expanded by this | |||
1098 | // pack expansion. | |||
1099 | if (auto Result = PackScope.finish()) | |||
1100 | return Result; | |||
1101 | } | |||
1102 | ||||
1103 | // Make sure we don't have any extra arguments. | |||
1104 | if (ArgIdx < NumArgs) | |||
1105 | return Sema::TDK_MiscellaneousDeductionFailure; | |||
1106 | ||||
1107 | return Sema::TDK_Success; | |||
1108 | } | |||
1109 | ||||
1110 | /// Determine whether the parameter has qualifiers that the argument | |||
1111 | /// lacks. Put another way, determine whether there is no way to add | |||
1112 | /// a deduced set of qualifiers to the ParamType that would result in | |||
1113 | /// its qualifiers matching those of the ArgType. | |||
1114 | static bool hasInconsistentOrSupersetQualifiersOf(QualType ParamType, | |||
1115 | QualType ArgType) { | |||
1116 | Qualifiers ParamQs = ParamType.getQualifiers(); | |||
1117 | Qualifiers ArgQs = ArgType.getQualifiers(); | |||
1118 | ||||
1119 | if (ParamQs == ArgQs) | |||
1120 | return false; | |||
1121 | ||||
1122 | // Mismatched (but not missing) Objective-C GC attributes. | |||
1123 | if (ParamQs.getObjCGCAttr() != ArgQs.getObjCGCAttr() && | |||
1124 | ParamQs.hasObjCGCAttr()) | |||
1125 | return true; | |||
1126 | ||||
1127 | // Mismatched (but not missing) address spaces. | |||
1128 | if (ParamQs.getAddressSpace() != ArgQs.getAddressSpace() && | |||
1129 | ParamQs.hasAddressSpace()) | |||
1130 | return true; | |||
1131 | ||||
1132 | // Mismatched (but not missing) Objective-C lifetime qualifiers. | |||
1133 | if (ParamQs.getObjCLifetime() != ArgQs.getObjCLifetime() && | |||
1134 | ParamQs.hasObjCLifetime()) | |||
1135 | return true; | |||
1136 | ||||
1137 | // CVR qualifiers inconsistent or a superset. | |||
1138 | return (ParamQs.getCVRQualifiers() & ~ArgQs.getCVRQualifiers()) != 0; | |||
1139 | } | |||
1140 | ||||
1141 | /// Compare types for equality with respect to possibly compatible | |||
1142 | /// function types (noreturn adjustment, implicit calling conventions). If any | |||
1143 | /// of parameter and argument is not a function, just perform type comparison. | |||
1144 | /// | |||
1145 | /// \param P the template parameter type. | |||
1146 | /// | |||
1147 | /// \param A the argument type. | |||
1148 | bool Sema::isSameOrCompatibleFunctionType(QualType P, QualType A) { | |||
1149 | const FunctionType *PF = P->getAs<FunctionType>(), | |||
1150 | *AF = A->getAs<FunctionType>(); | |||
1151 | ||||
1152 | // Just compare if not functions. | |||
1153 | if (!PF || !AF) | |||
1154 | return Context.hasSameType(P, A); | |||
1155 | ||||
1156 | // Noreturn and noexcept adjustment. | |||
1157 | QualType AdjustedParam; | |||
1158 | if (IsFunctionConversion(P, A, AdjustedParam)) | |||
1159 | return Context.hasSameType(AdjustedParam, A); | |||
1160 | ||||
1161 | // FIXME: Compatible calling conventions. | |||
1162 | ||||
1163 | return Context.hasSameType(P, A); | |||
1164 | } | |||
1165 | ||||
1166 | /// Get the index of the first template parameter that was originally from the | |||
1167 | /// innermost template-parameter-list. This is 0 except when we concatenate | |||
1168 | /// the template parameter lists of a class template and a constructor template | |||
1169 | /// when forming an implicit deduction guide. | |||
1170 | static unsigned getFirstInnerIndex(FunctionTemplateDecl *FTD) { | |||
1171 | auto *Guide = dyn_cast<CXXDeductionGuideDecl>(FTD->getTemplatedDecl()); | |||
1172 | if (!Guide || !Guide->isImplicit()) | |||
1173 | return 0; | |||
1174 | return Guide->getDeducedTemplate()->getTemplateParameters()->size(); | |||
1175 | } | |||
1176 | ||||
1177 | /// Determine whether a type denotes a forwarding reference. | |||
1178 | static bool isForwardingReference(QualType Param, unsigned FirstInnerIndex) { | |||
1179 | // C++1z [temp.deduct.call]p3: | |||
1180 | // A forwarding reference is an rvalue reference to a cv-unqualified | |||
1181 | // template parameter that does not represent a template parameter of a | |||
1182 | // class template. | |||
1183 | if (auto *ParamRef = Param->getAs<RValueReferenceType>()) { | |||
1184 | if (ParamRef->getPointeeType().getQualifiers()) | |||
1185 | return false; | |||
1186 | auto *TypeParm = ParamRef->getPointeeType()->getAs<TemplateTypeParmType>(); | |||
1187 | return TypeParm && TypeParm->getIndex() >= FirstInnerIndex; | |||
1188 | } | |||
1189 | return false; | |||
1190 | } | |||
1191 | ||||
1192 | static CXXRecordDecl *getCanonicalRD(QualType T) { | |||
1193 | return cast<CXXRecordDecl>( | |||
1194 | T->castAs<RecordType>()->getDecl()->getCanonicalDecl()); | |||
1195 | } | |||
1196 | ||||
1197 | /// Attempt to deduce the template arguments by checking the base types | |||
1198 | /// according to (C++20 [temp.deduct.call] p4b3. | |||
1199 | /// | |||
1200 | /// \param S the semantic analysis object within which we are deducing. | |||
1201 | /// | |||
1202 | /// \param RD the top level record object we are deducing against. | |||
1203 | /// | |||
1204 | /// \param TemplateParams the template parameters that we are deducing. | |||
1205 | /// | |||
1206 | /// \param P the template specialization parameter type. | |||
1207 | /// | |||
1208 | /// \param Info information about the template argument deduction itself. | |||
1209 | /// | |||
1210 | /// \param Deduced the deduced template arguments. | |||
1211 | /// | |||
1212 | /// \returns the result of template argument deduction with the bases. "invalid" | |||
1213 | /// means no matches, "success" found a single item, and the | |||
1214 | /// "MiscellaneousDeductionFailure" result happens when the match is ambiguous. | |||
1215 | static Sema::TemplateDeductionResult | |||
1216 | DeduceTemplateBases(Sema &S, const CXXRecordDecl *RD, | |||
1217 | TemplateParameterList *TemplateParams, QualType P, | |||
1218 | TemplateDeductionInfo &Info, | |||
1219 | SmallVectorImpl<DeducedTemplateArgument> &Deduced) { | |||
1220 | // C++14 [temp.deduct.call] p4b3: | |||
1221 | // If P is a class and P has the form simple-template-id, then the | |||
1222 | // transformed A can be a derived class of the deduced A. Likewise if | |||
1223 | // P is a pointer to a class of the form simple-template-id, the | |||
1224 | // transformed A can be a pointer to a derived class pointed to by the | |||
1225 | // deduced A. However, if there is a class C that is a (direct or | |||
1226 | // indirect) base class of D and derived (directly or indirectly) from a | |||
1227 | // class B and that would be a valid deduced A, the deduced A cannot be | |||
1228 | // B or pointer to B, respectively. | |||
1229 | // | |||
1230 | // These alternatives are considered only if type deduction would | |||
1231 | // otherwise fail. If they yield more than one possible deduced A, the | |||
1232 | // type deduction fails. | |||
1233 | ||||
1234 | // Use a breadth-first search through the bases to collect the set of | |||
1235 | // successful matches. Visited contains the set of nodes we have already | |||
1236 | // visited, while ToVisit is our stack of records that we still need to | |||
1237 | // visit. Matches contains a list of matches that have yet to be | |||
1238 | // disqualified. | |||
1239 | llvm::SmallPtrSet<const CXXRecordDecl *, 8> Visited; | |||
1240 | SmallVector<QualType, 8> ToVisit; | |||
1241 | // We iterate over this later, so we have to use MapVector to ensure | |||
1242 | // determinism. | |||
1243 | llvm::MapVector<const CXXRecordDecl *, | |||
1244 | SmallVector<DeducedTemplateArgument, 8>> | |||
1245 | Matches; | |||
1246 | ||||
1247 | auto AddBases = [&Visited, &ToVisit](const CXXRecordDecl *RD) { | |||
1248 | for (const auto &Base : RD->bases()) { | |||
1249 | QualType T = Base.getType(); | |||
1250 | assert(T->isRecordType() && "Base class that isn't a record?")(static_cast <bool> (T->isRecordType() && "Base class that isn't a record?" ) ? void (0) : __assert_fail ("T->isRecordType() && \"Base class that isn't a record?\"" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 1250, __extension__ __PRETTY_FUNCTION__)); | |||
1251 | if (Visited.insert(::getCanonicalRD(T)).second) | |||
1252 | ToVisit.push_back(T); | |||
1253 | } | |||
1254 | }; | |||
1255 | ||||
1256 | // Set up the loop by adding all the bases. | |||
1257 | AddBases(RD); | |||
1258 | ||||
1259 | // Search each path of bases until we either run into a successful match | |||
1260 | // (where all bases of it are invalid), or we run out of bases. | |||
1261 | while (!ToVisit.empty()) { | |||
1262 | QualType NextT = ToVisit.pop_back_val(); | |||
1263 | ||||
1264 | SmallVector<DeducedTemplateArgument, 8> DeducedCopy(Deduced.begin(), | |||
1265 | Deduced.end()); | |||
1266 | TemplateDeductionInfo BaseInfo(TemplateDeductionInfo::ForBase, Info); | |||
1267 | Sema::TemplateDeductionResult BaseResult = DeduceTemplateSpecArguments( | |||
1268 | S, TemplateParams, P, NextT, BaseInfo, DeducedCopy); | |||
1269 | ||||
1270 | // If this was a successful deduction, add it to the list of matches, | |||
1271 | // otherwise we need to continue searching its bases. | |||
1272 | const CXXRecordDecl *RD = ::getCanonicalRD(NextT); | |||
1273 | if (BaseResult == Sema::TDK_Success) | |||
1274 | Matches.insert({RD, DeducedCopy}); | |||
1275 | else | |||
1276 | AddBases(RD); | |||
1277 | } | |||
1278 | ||||
1279 | // At this point, 'Matches' contains a list of seemingly valid bases, however | |||
1280 | // in the event that we have more than 1 match, it is possible that the base | |||
1281 | // of one of the matches might be disqualified for being a base of another | |||
1282 | // valid match. We can count on cyclical instantiations being invalid to | |||
1283 | // simplify the disqualifications. That is, if A & B are both matches, and B | |||
1284 | // inherits from A (disqualifying A), we know that A cannot inherit from B. | |||
1285 | if (Matches.size() > 1) { | |||
1286 | Visited.clear(); | |||
1287 | for (const auto &Match : Matches) | |||
1288 | AddBases(Match.first); | |||
1289 | ||||
1290 | // We can give up once we have a single item (or have run out of things to | |||
1291 | // search) since cyclical inheritance isn't valid. | |||
1292 | while (Matches.size() > 1 && !ToVisit.empty()) { | |||
1293 | const CXXRecordDecl *RD = ::getCanonicalRD(ToVisit.pop_back_val()); | |||
1294 | Matches.erase(RD); | |||
1295 | ||||
1296 | // Always add all bases, since the inheritance tree can contain | |||
1297 | // disqualifications for multiple matches. | |||
1298 | AddBases(RD); | |||
1299 | } | |||
1300 | } | |||
1301 | ||||
1302 | if (Matches.empty()) | |||
1303 | return Sema::TDK_Invalid; | |||
1304 | if (Matches.size() > 1) | |||
1305 | return Sema::TDK_MiscellaneousDeductionFailure; | |||
1306 | ||||
1307 | std::swap(Matches.front().second, Deduced); | |||
1308 | return Sema::TDK_Success; | |||
1309 | } | |||
1310 | ||||
1311 | /// Deduce the template arguments by comparing the parameter type and | |||
1312 | /// the argument type (C++ [temp.deduct.type]). | |||
1313 | /// | |||
1314 | /// \param S the semantic analysis object within which we are deducing | |||
1315 | /// | |||
1316 | /// \param TemplateParams the template parameters that we are deducing | |||
1317 | /// | |||
1318 | /// \param P the parameter type | |||
1319 | /// | |||
1320 | /// \param A the argument type | |||
1321 | /// | |||
1322 | /// \param Info information about the template argument deduction itself | |||
1323 | /// | |||
1324 | /// \param Deduced the deduced template arguments | |||
1325 | /// | |||
1326 | /// \param TDF bitwise OR of the TemplateDeductionFlags bits that describe | |||
1327 | /// how template argument deduction is performed. | |||
1328 | /// | |||
1329 | /// \param PartialOrdering Whether we're performing template argument deduction | |||
1330 | /// in the context of partial ordering (C++0x [temp.deduct.partial]). | |||
1331 | /// | |||
1332 | /// \returns the result of template argument deduction so far. Note that a | |||
1333 | /// "success" result means that template argument deduction has not yet failed, | |||
1334 | /// but it may still fail, later, for other reasons. | |||
1335 | static Sema::TemplateDeductionResult DeduceTemplateArgumentsByTypeMatch( | |||
1336 | Sema &S, TemplateParameterList *TemplateParams, QualType P, QualType A, | |||
1337 | TemplateDeductionInfo &Info, | |||
1338 | SmallVectorImpl<DeducedTemplateArgument> &Deduced, unsigned TDF, | |||
1339 | bool PartialOrdering, bool DeducedFromArrayBound) { | |||
1340 | ||||
1341 | // If the argument type is a pack expansion, look at its pattern. | |||
1342 | // This isn't explicitly called out | |||
1343 | if (const auto *AExp
| |||
| ||||
1344 | A = AExp->getPattern(); | |||
1345 | assert(!isa<PackExpansionType>(A.getCanonicalType()))(static_cast <bool> (!isa<PackExpansionType>(A.getCanonicalType ())) ? void (0) : __assert_fail ("!isa<PackExpansionType>(A.getCanonicalType())" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 1345, __extension__ __PRETTY_FUNCTION__)); | |||
1346 | ||||
1347 | if (PartialOrdering) { | |||
1348 | // C++11 [temp.deduct.partial]p5: | |||
1349 | // Before the partial ordering is done, certain transformations are | |||
1350 | // performed on the types used for partial ordering: | |||
1351 | // - If P is a reference type, P is replaced by the type referred to. | |||
1352 | const ReferenceType *PRef = P->getAs<ReferenceType>(); | |||
1353 | if (PRef) | |||
1354 | P = PRef->getPointeeType(); | |||
1355 | ||||
1356 | // - If A is a reference type, A is replaced by the type referred to. | |||
1357 | const ReferenceType *ARef = A->getAs<ReferenceType>(); | |||
1358 | if (ARef) | |||
1359 | A = A->getPointeeType(); | |||
1360 | ||||
1361 | if (PRef && ARef && S.Context.hasSameUnqualifiedType(P, A)) { | |||
1362 | // C++11 [temp.deduct.partial]p9: | |||
1363 | // If, for a given type, deduction succeeds in both directions (i.e., | |||
1364 | // the types are identical after the transformations above) and both | |||
1365 | // P and A were reference types [...]: | |||
1366 | // - if [one type] was an lvalue reference and [the other type] was | |||
1367 | // not, [the other type] is not considered to be at least as | |||
1368 | // specialized as [the first type] | |||
1369 | // - if [one type] is more cv-qualified than [the other type], | |||
1370 | // [the other type] is not considered to be at least as specialized | |||
1371 | // as [the first type] | |||
1372 | // Objective-C ARC adds: | |||
1373 | // - [one type] has non-trivial lifetime, [the other type] has | |||
1374 | // __unsafe_unretained lifetime, and the types are otherwise | |||
1375 | // identical | |||
1376 | // | |||
1377 | // A is "considered to be at least as specialized" as P iff deduction | |||
1378 | // succeeds, so we model this as a deduction failure. Note that | |||
1379 | // [the first type] is P and [the other type] is A here; the standard | |||
1380 | // gets this backwards. | |||
1381 | Qualifiers PQuals = P.getQualifiers(), AQuals = A.getQualifiers(); | |||
1382 | if ((PRef->isLValueReferenceType() && !ARef->isLValueReferenceType()) || | |||
1383 | PQuals.isStrictSupersetOf(AQuals) || | |||
1384 | (PQuals.hasNonTrivialObjCLifetime() && | |||
1385 | AQuals.getObjCLifetime() == Qualifiers::OCL_ExplicitNone && | |||
1386 | PQuals.withoutObjCLifetime() == AQuals.withoutObjCLifetime())) { | |||
1387 | Info.FirstArg = TemplateArgument(P); | |||
1388 | Info.SecondArg = TemplateArgument(A); | |||
1389 | return Sema::TDK_NonDeducedMismatch; | |||
1390 | } | |||
1391 | } | |||
1392 | Qualifiers DiscardedQuals; | |||
1393 | // C++11 [temp.deduct.partial]p7: | |||
1394 | // Remove any top-level cv-qualifiers: | |||
1395 | // - If P is a cv-qualified type, P is replaced by the cv-unqualified | |||
1396 | // version of P. | |||
1397 | P = S.Context.getUnqualifiedArrayType(P, DiscardedQuals); | |||
1398 | // - If A is a cv-qualified type, A is replaced by the cv-unqualified | |||
1399 | // version of A. | |||
1400 | A = S.Context.getUnqualifiedArrayType(A, DiscardedQuals); | |||
1401 | } else { | |||
1402 | // C++0x [temp.deduct.call]p4 bullet 1: | |||
1403 | // - If the original P is a reference type, the deduced A (i.e., the type | |||
1404 | // referred to by the reference) can be more cv-qualified than the | |||
1405 | // transformed A. | |||
1406 | if (TDF & TDF_ParamWithReferenceType) { | |||
1407 | Qualifiers Quals; | |||
1408 | QualType UnqualP = S.Context.getUnqualifiedArrayType(P, Quals); | |||
1409 | Quals.setCVRQualifiers(Quals.getCVRQualifiers() & A.getCVRQualifiers()); | |||
1410 | P = S.Context.getQualifiedType(UnqualP, Quals); | |||
1411 | } | |||
1412 | ||||
1413 | if ((TDF & TDF_TopLevelParameterTypeList) && !P->isFunctionType()) { | |||
1414 | // C++0x [temp.deduct.type]p10: | |||
1415 | // If P and A are function types that originated from deduction when | |||
1416 | // taking the address of a function template (14.8.2.2) or when deducing | |||
1417 | // template arguments from a function declaration (14.8.2.6) and Pi and | |||
1418 | // Ai are parameters of the top-level parameter-type-list of P and A, | |||
1419 | // respectively, Pi is adjusted if it is a forwarding reference and Ai | |||
1420 | // is an lvalue reference, in | |||
1421 | // which case the type of Pi is changed to be the template parameter | |||
1422 | // type (i.e., T&& is changed to simply T). [ Note: As a result, when | |||
1423 | // Pi is T&& and Ai is X&, the adjusted Pi will be T, causing T to be | |||
1424 | // deduced as X&. - end note ] | |||
1425 | TDF &= ~TDF_TopLevelParameterTypeList; | |||
1426 | if (isForwardingReference(P, /*FirstInnerIndex=*/0) && | |||
1427 | A->isLValueReferenceType()) | |||
1428 | P = P->getPointeeType(); | |||
1429 | } | |||
1430 | } | |||
1431 | ||||
1432 | // C++ [temp.deduct.type]p9: | |||
1433 | // A template type argument T, a template template argument TT or a | |||
1434 | // template non-type argument i can be deduced if P and A have one of | |||
1435 | // the following forms: | |||
1436 | // | |||
1437 | // T | |||
1438 | // cv-list T | |||
1439 | if (const auto *TTP
| |||
1440 | // Just skip any attempts to deduce from a placeholder type or a parameter | |||
1441 | // at a different depth. | |||
1442 | if (A->isPlaceholderType() || Info.getDeducedDepth() != TTP->getDepth()) | |||
1443 | return Sema::TDK_Success; | |||
1444 | ||||
1445 | unsigned Index = TTP->getIndex(); | |||
1446 | ||||
1447 | // If the argument type is an array type, move the qualifiers up to the | |||
1448 | // top level, so they can be matched with the qualifiers on the parameter. | |||
1449 | if (A->isArrayType()) { | |||
1450 | Qualifiers Quals; | |||
1451 | A = S.Context.getUnqualifiedArrayType(A, Quals); | |||
1452 | if (Quals) | |||
1453 | A = S.Context.getQualifiedType(A, Quals); | |||
1454 | } | |||
1455 | ||||
1456 | // The argument type can not be less qualified than the parameter | |||
1457 | // type. | |||
1458 | if (!(TDF & TDF_IgnoreQualifiers) && | |||
1459 | hasInconsistentOrSupersetQualifiersOf(P, A)) { | |||
1460 | Info.Param = cast<TemplateTypeParmDecl>(TemplateParams->getParam(Index)); | |||
1461 | Info.FirstArg = TemplateArgument(P); | |||
1462 | Info.SecondArg = TemplateArgument(A); | |||
1463 | return Sema::TDK_Underqualified; | |||
1464 | } | |||
1465 | ||||
1466 | // Do not match a function type with a cv-qualified type. | |||
1467 | // http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#1584 | |||
1468 | if (A->isFunctionType() && P.hasQualifiers()) | |||
1469 | return Sema::TDK_NonDeducedMismatch; | |||
1470 | ||||
1471 | assert(TTP->getDepth() == Info.getDeducedDepth() &&(static_cast <bool> (TTP->getDepth() == Info.getDeducedDepth () && "saw template type parameter with wrong depth") ? void (0) : __assert_fail ("TTP->getDepth() == Info.getDeducedDepth() && \"saw template type parameter with wrong depth\"" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 1472, __extension__ __PRETTY_FUNCTION__)) | |||
1472 | "saw template type parameter with wrong depth")(static_cast <bool> (TTP->getDepth() == Info.getDeducedDepth () && "saw template type parameter with wrong depth") ? void (0) : __assert_fail ("TTP->getDepth() == Info.getDeducedDepth() && \"saw template type parameter with wrong depth\"" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 1472, __extension__ __PRETTY_FUNCTION__)); | |||
1473 | assert(A->getCanonicalTypeInternal() != S.Context.OverloadTy &&(static_cast <bool> (A->getCanonicalTypeInternal() != S.Context.OverloadTy && "Unresolved overloaded function" ) ? void (0) : __assert_fail ("A->getCanonicalTypeInternal() != S.Context.OverloadTy && \"Unresolved overloaded function\"" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 1474, __extension__ __PRETTY_FUNCTION__)) | |||
1474 | "Unresolved overloaded function")(static_cast <bool> (A->getCanonicalTypeInternal() != S.Context.OverloadTy && "Unresolved overloaded function" ) ? void (0) : __assert_fail ("A->getCanonicalTypeInternal() != S.Context.OverloadTy && \"Unresolved overloaded function\"" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 1474, __extension__ __PRETTY_FUNCTION__)); | |||
1475 | QualType DeducedType = A; | |||
1476 | ||||
1477 | // Remove any qualifiers on the parameter from the deduced type. | |||
1478 | // We checked the qualifiers for consistency above. | |||
1479 | Qualifiers DeducedQs = DeducedType.getQualifiers(); | |||
1480 | Qualifiers ParamQs = P.getQualifiers(); | |||
1481 | DeducedQs.removeCVRQualifiers(ParamQs.getCVRQualifiers()); | |||
1482 | if (ParamQs.hasObjCGCAttr()) | |||
1483 | DeducedQs.removeObjCGCAttr(); | |||
1484 | if (ParamQs.hasAddressSpace()) | |||
1485 | DeducedQs.removeAddressSpace(); | |||
1486 | if (ParamQs.hasObjCLifetime()) | |||
1487 | DeducedQs.removeObjCLifetime(); | |||
1488 | ||||
1489 | // Objective-C ARC: | |||
1490 | // If template deduction would produce a lifetime qualifier on a type | |||
1491 | // that is not a lifetime type, template argument deduction fails. | |||
1492 | if (ParamQs.hasObjCLifetime() && !DeducedType->isObjCLifetimeType() && | |||
1493 | !DeducedType->isDependentType()) { | |||
1494 | Info.Param = cast<TemplateTypeParmDecl>(TemplateParams->getParam(Index)); | |||
1495 | Info.FirstArg = TemplateArgument(P); | |||
1496 | Info.SecondArg = TemplateArgument(A); | |||
1497 | return Sema::TDK_Underqualified; | |||
1498 | } | |||
1499 | ||||
1500 | // Objective-C ARC: | |||
1501 | // If template deduction would produce an argument type with lifetime type | |||
1502 | // but no lifetime qualifier, the __strong lifetime qualifier is inferred. | |||
1503 | if (S.getLangOpts().ObjCAutoRefCount && DeducedType->isObjCLifetimeType() && | |||
1504 | !DeducedQs.hasObjCLifetime()) | |||
1505 | DeducedQs.setObjCLifetime(Qualifiers::OCL_Strong); | |||
1506 | ||||
1507 | DeducedType = | |||
1508 | S.Context.getQualifiedType(DeducedType.getUnqualifiedType(), DeducedQs); | |||
1509 | ||||
1510 | DeducedTemplateArgument NewDeduced(DeducedType, DeducedFromArrayBound); | |||
1511 | DeducedTemplateArgument Result = | |||
1512 | checkDeducedTemplateArguments(S.Context, Deduced[Index], NewDeduced); | |||
1513 | if (Result.isNull()) { | |||
1514 | Info.Param = cast<TemplateTypeParmDecl>(TemplateParams->getParam(Index)); | |||
1515 | Info.FirstArg = Deduced[Index]; | |||
1516 | Info.SecondArg = NewDeduced; | |||
1517 | return Sema::TDK_Inconsistent; | |||
1518 | } | |||
1519 | ||||
1520 | Deduced[Index] = Result; | |||
1521 | return Sema::TDK_Success; | |||
1522 | } | |||
1523 | ||||
1524 | // Set up the template argument deduction information for a failure. | |||
1525 | Info.FirstArg = TemplateArgument(P); | |||
1526 | Info.SecondArg = TemplateArgument(A); | |||
1527 | ||||
1528 | // If the parameter is an already-substituted template parameter | |||
1529 | // pack, do nothing: we don't know which of its arguments to look | |||
1530 | // at, so we have to wait until all of the parameter packs in this | |||
1531 | // expansion have arguments. | |||
1532 | if (P->getAs<SubstTemplateTypeParmPackType>()) | |||
1533 | return Sema::TDK_Success; | |||
1534 | ||||
1535 | // Check the cv-qualifiers on the parameter and argument types. | |||
1536 | if (!(TDF & TDF_IgnoreQualifiers)) { | |||
1537 | if (TDF & TDF_ParamWithReferenceType) { | |||
1538 | if (hasInconsistentOrSupersetQualifiersOf(P, A)) | |||
1539 | return Sema::TDK_NonDeducedMismatch; | |||
1540 | } else if (TDF & TDF_ArgWithReferenceType) { | |||
1541 | // C++ [temp.deduct.conv]p4: | |||
1542 | // If the original A is a reference type, A can be more cv-qualified | |||
1543 | // than the deduced A | |||
1544 | if (!A.getQualifiers().compatiblyIncludes(P.getQualifiers())) | |||
1545 | return Sema::TDK_NonDeducedMismatch; | |||
1546 | ||||
1547 | // Strip out all extra qualifiers from the argument to figure out the | |||
1548 | // type we're converting to, prior to the qualification conversion. | |||
1549 | Qualifiers Quals; | |||
1550 | A = S.Context.getUnqualifiedArrayType(A, Quals); | |||
1551 | A = S.Context.getQualifiedType(A, P.getQualifiers()); | |||
1552 | } else if (!IsPossiblyOpaquelyQualifiedType(P)) { | |||
1553 | if (P.getCVRQualifiers() != A.getCVRQualifiers()) | |||
1554 | return Sema::TDK_NonDeducedMismatch; | |||
1555 | } | |||
1556 | } | |||
1557 | ||||
1558 | // If the parameter type is not dependent, there is nothing to deduce. | |||
1559 | if (!P->isDependentType()) { | |||
1560 | if (TDF & TDF_SkipNonDependent) | |||
1561 | return Sema::TDK_Success; | |||
1562 | if ((TDF & TDF_IgnoreQualifiers) ? S.Context.hasSameUnqualifiedType(P, A) | |||
1563 | : S.Context.hasSameType(P, A)) | |||
1564 | return Sema::TDK_Success; | |||
1565 | if (TDF & TDF_AllowCompatibleFunctionType && | |||
1566 | S.isSameOrCompatibleFunctionType(P, A)) | |||
1567 | return Sema::TDK_Success; | |||
1568 | if (!(TDF & TDF_IgnoreQualifiers)) | |||
1569 | return Sema::TDK_NonDeducedMismatch; | |||
1570 | // Otherwise, when ignoring qualifiers, the types not having the same | |||
1571 | // unqualified type does not mean they do not match, so in this case we | |||
1572 | // must keep going and analyze with a non-dependent parameter type. | |||
1573 | } | |||
1574 | ||||
1575 | switch (P.getCanonicalType()->getTypeClass()) { | |||
1576 | // Non-canonical types cannot appear here. | |||
1577 | #define NON_CANONICAL_TYPE(Class, Base) \ | |||
1578 | case Type::Class: llvm_unreachable("deducing non-canonical type: " #Class)::llvm::llvm_unreachable_internal("deducing non-canonical type: " #Class, "clang/lib/Sema/SemaTemplateDeduction.cpp", 1578); | |||
1579 | #define TYPE(Class, Base) | |||
1580 | #include "clang/AST/TypeNodes.inc" | |||
1581 | ||||
1582 | case Type::TemplateTypeParm: | |||
1583 | case Type::SubstTemplateTypeParmPack: | |||
1584 | llvm_unreachable("Type nodes handled above")::llvm::llvm_unreachable_internal("Type nodes handled above", "clang/lib/Sema/SemaTemplateDeduction.cpp", 1584); | |||
1585 | ||||
1586 | case Type::Auto: | |||
1587 | // FIXME: Implement deduction in dependent case. | |||
1588 | if (P->isDependentType()) | |||
1589 | return Sema::TDK_Success; | |||
1590 | LLVM_FALLTHROUGH[[gnu::fallthrough]]; | |||
1591 | case Type::Builtin: | |||
1592 | case Type::VariableArray: | |||
1593 | case Type::Vector: | |||
1594 | case Type::FunctionNoProto: | |||
1595 | case Type::Record: | |||
1596 | case Type::Enum: | |||
1597 | case Type::ObjCObject: | |||
1598 | case Type::ObjCInterface: | |||
1599 | case Type::ObjCObjectPointer: | |||
1600 | case Type::BitInt: | |||
1601 | return (TDF & TDF_SkipNonDependent) || | |||
1602 | ((TDF & TDF_IgnoreQualifiers) | |||
1603 | ? S.Context.hasSameUnqualifiedType(P, A) | |||
1604 | : S.Context.hasSameType(P, A)) | |||
1605 | ? Sema::TDK_Success | |||
1606 | : Sema::TDK_NonDeducedMismatch; | |||
1607 | ||||
1608 | // _Complex T [placeholder extension] | |||
1609 | case Type::Complex: { | |||
1610 | const auto *CP = P->castAs<ComplexType>(), *CA = A->getAs<ComplexType>(); | |||
1611 | if (!CA) | |||
1612 | return Sema::TDK_NonDeducedMismatch; | |||
1613 | return DeduceTemplateArgumentsByTypeMatch( | |||
1614 | S, TemplateParams, CP->getElementType(), CA->getElementType(), Info, | |||
1615 | Deduced, TDF); | |||
1616 | } | |||
1617 | ||||
1618 | // _Atomic T [extension] | |||
1619 | case Type::Atomic: { | |||
1620 | const auto *PA = P->castAs<AtomicType>(), *AA = A->getAs<AtomicType>(); | |||
1621 | if (!AA) | |||
1622 | return Sema::TDK_NonDeducedMismatch; | |||
1623 | return DeduceTemplateArgumentsByTypeMatch( | |||
1624 | S, TemplateParams, PA->getValueType(), AA->getValueType(), Info, | |||
1625 | Deduced, TDF); | |||
1626 | } | |||
1627 | ||||
1628 | // T * | |||
1629 | case Type::Pointer: { | |||
1630 | QualType PointeeType; | |||
1631 | if (const auto *PA = A->getAs<PointerType>()) { | |||
1632 | PointeeType = PA->getPointeeType(); | |||
1633 | } else if (const auto *PA = A->getAs<ObjCObjectPointerType>()) { | |||
1634 | PointeeType = PA->getPointeeType(); | |||
1635 | } else { | |||
1636 | return Sema::TDK_NonDeducedMismatch; | |||
1637 | } | |||
1638 | return DeduceTemplateArgumentsByTypeMatch( | |||
1639 | S, TemplateParams, P->castAs<PointerType>()->getPointeeType(), | |||
1640 | PointeeType, Info, Deduced, | |||
1641 | TDF & (TDF_IgnoreQualifiers | TDF_DerivedClass)); | |||
1642 | } | |||
1643 | ||||
1644 | // T & | |||
1645 | case Type::LValueReference: { | |||
1646 | const auto *RP = P->castAs<LValueReferenceType>(), | |||
1647 | *RA = A->getAs<LValueReferenceType>(); | |||
1648 | if (!RA) | |||
1649 | return Sema::TDK_NonDeducedMismatch; | |||
1650 | ||||
1651 | return DeduceTemplateArgumentsByTypeMatch( | |||
1652 | S, TemplateParams, RP->getPointeeType(), RA->getPointeeType(), Info, | |||
1653 | Deduced, 0); | |||
1654 | } | |||
1655 | ||||
1656 | // T && [C++0x] | |||
1657 | case Type::RValueReference: { | |||
1658 | const auto *RP = P->castAs<RValueReferenceType>(), | |||
1659 | *RA = A->getAs<RValueReferenceType>(); | |||
1660 | if (!RA) | |||
1661 | return Sema::TDK_NonDeducedMismatch; | |||
1662 | ||||
1663 | return DeduceTemplateArgumentsByTypeMatch( | |||
1664 | S, TemplateParams, RP->getPointeeType(), RA->getPointeeType(), Info, | |||
1665 | Deduced, 0); | |||
1666 | } | |||
1667 | ||||
1668 | // T [] (implied, but not stated explicitly) | |||
1669 | case Type::IncompleteArray: { | |||
1670 | const auto *IAA = S.Context.getAsIncompleteArrayType(A); | |||
1671 | if (!IAA) | |||
1672 | return Sema::TDK_NonDeducedMismatch; | |||
1673 | ||||
1674 | return DeduceTemplateArgumentsByTypeMatch( | |||
1675 | S, TemplateParams, | |||
1676 | S.Context.getAsIncompleteArrayType(P)->getElementType(), | |||
1677 | IAA->getElementType(), Info, Deduced, TDF & TDF_IgnoreQualifiers); | |||
1678 | } | |||
1679 | ||||
1680 | // T [integer-constant] | |||
1681 | case Type::ConstantArray: { | |||
1682 | const auto *CAA = S.Context.getAsConstantArrayType(A), | |||
1683 | *CAP = S.Context.getAsConstantArrayType(P); | |||
1684 | assert(CAP)(static_cast <bool> (CAP) ? void (0) : __assert_fail ("CAP" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 1684, __extension__ __PRETTY_FUNCTION__)); | |||
1685 | if (!CAA || CAA->getSize() != CAP->getSize()) | |||
1686 | return Sema::TDK_NonDeducedMismatch; | |||
1687 | ||||
1688 | return DeduceTemplateArgumentsByTypeMatch( | |||
1689 | S, TemplateParams, CAP->getElementType(), CAA->getElementType(), Info, | |||
1690 | Deduced, TDF & TDF_IgnoreQualifiers); | |||
1691 | } | |||
1692 | ||||
1693 | // type [i] | |||
1694 | case Type::DependentSizedArray: { | |||
1695 | const auto *AA = S.Context.getAsArrayType(A); | |||
1696 | if (!AA) | |||
1697 | return Sema::TDK_NonDeducedMismatch; | |||
1698 | ||||
1699 | // Check the element type of the arrays | |||
1700 | const auto *DAP = S.Context.getAsDependentSizedArrayType(P); | |||
1701 | assert(DAP)(static_cast <bool> (DAP) ? void (0) : __assert_fail ("DAP" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 1701, __extension__ __PRETTY_FUNCTION__)); | |||
1702 | if (auto Result = DeduceTemplateArgumentsByTypeMatch( | |||
1703 | S, TemplateParams, DAP->getElementType(), AA->getElementType(), | |||
1704 | Info, Deduced, TDF & TDF_IgnoreQualifiers)) | |||
1705 | return Result; | |||
1706 | ||||
1707 | // Determine the array bound is something we can deduce. | |||
1708 | const NonTypeTemplateParmDecl *NTTP = | |||
1709 | getDeducedParameterFromExpr(Info, DAP->getSizeExpr()); | |||
1710 | if (!NTTP) | |||
1711 | return Sema::TDK_Success; | |||
1712 | ||||
1713 | // We can perform template argument deduction for the given non-type | |||
1714 | // template parameter. | |||
1715 | assert(NTTP->getDepth() == Info.getDeducedDepth() &&(static_cast <bool> (NTTP->getDepth() == Info.getDeducedDepth () && "saw non-type template parameter with wrong depth" ) ? void (0) : __assert_fail ("NTTP->getDepth() == Info.getDeducedDepth() && \"saw non-type template parameter with wrong depth\"" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 1716, __extension__ __PRETTY_FUNCTION__)) | |||
1716 | "saw non-type template parameter with wrong depth")(static_cast <bool> (NTTP->getDepth() == Info.getDeducedDepth () && "saw non-type template parameter with wrong depth" ) ? void (0) : __assert_fail ("NTTP->getDepth() == Info.getDeducedDepth() && \"saw non-type template parameter with wrong depth\"" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 1716, __extension__ __PRETTY_FUNCTION__)); | |||
1717 | if (const auto *CAA = dyn_cast<ConstantArrayType>(AA)) { | |||
1718 | llvm::APSInt Size(CAA->getSize()); | |||
1719 | return DeduceNonTypeTemplateArgument( | |||
1720 | S, TemplateParams, NTTP, Size, S.Context.getSizeType(), | |||
1721 | /*ArrayBound=*/true, Info, Deduced); | |||
1722 | } | |||
1723 | if (const auto *DAA = dyn_cast<DependentSizedArrayType>(AA)) | |||
1724 | if (DAA->getSizeExpr()) | |||
1725 | return DeduceNonTypeTemplateArgument( | |||
1726 | S, TemplateParams, NTTP, DAA->getSizeExpr(), Info, Deduced); | |||
1727 | ||||
1728 | // Incomplete type does not match a dependently-sized array type | |||
1729 | return Sema::TDK_NonDeducedMismatch; | |||
1730 | } | |||
1731 | ||||
1732 | // type(*)(T) | |||
1733 | // T(*)() | |||
1734 | // T(*)(T) | |||
1735 | case Type::FunctionProto: { | |||
1736 | const auto *FPP = P->castAs<FunctionProtoType>(), | |||
1737 | *FPA = A->getAs<FunctionProtoType>(); | |||
1738 | if (!FPA) | |||
1739 | return Sema::TDK_NonDeducedMismatch; | |||
1740 | ||||
1741 | if (FPP->getMethodQuals() != FPA->getMethodQuals() || | |||
1742 | FPP->getRefQualifier() != FPA->getRefQualifier() || | |||
1743 | FPP->isVariadic() != FPA->isVariadic()) | |||
1744 | return Sema::TDK_NonDeducedMismatch; | |||
1745 | ||||
1746 | // Check return types. | |||
1747 | if (auto Result = DeduceTemplateArgumentsByTypeMatch( | |||
1748 | S, TemplateParams, FPP->getReturnType(), FPA->getReturnType(), | |||
1749 | Info, Deduced, 0, | |||
1750 | /*PartialOrdering=*/false, | |||
1751 | /*DeducedFromArrayBound=*/false)) | |||
1752 | return Result; | |||
1753 | ||||
1754 | // Check parameter types. | |||
1755 | if (auto Result = DeduceTemplateArguments( | |||
1756 | S, TemplateParams, FPP->param_type_begin(), FPP->getNumParams(), | |||
1757 | FPA->param_type_begin(), FPA->getNumParams(), Info, Deduced, | |||
1758 | TDF & TDF_TopLevelParameterTypeList)) | |||
1759 | return Result; | |||
1760 | ||||
1761 | if (TDF & TDF_AllowCompatibleFunctionType) | |||
1762 | return Sema::TDK_Success; | |||
1763 | ||||
1764 | // FIXME: Per core-2016/10/1019 (no corresponding core issue yet), permit | |||
1765 | // deducing through the noexcept-specifier if it's part of the canonical | |||
1766 | // type. libstdc++ relies on this. | |||
1767 | Expr *NoexceptExpr = FPP->getNoexceptExpr(); | |||
1768 | if (const NonTypeTemplateParmDecl *NTTP = | |||
1769 | NoexceptExpr ? getDeducedParameterFromExpr(Info, NoexceptExpr) | |||
1770 | : nullptr) { | |||
1771 | assert(NTTP->getDepth() == Info.getDeducedDepth() &&(static_cast <bool> (NTTP->getDepth() == Info.getDeducedDepth () && "saw non-type template parameter with wrong depth" ) ? void (0) : __assert_fail ("NTTP->getDepth() == Info.getDeducedDepth() && \"saw non-type template parameter with wrong depth\"" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 1772, __extension__ __PRETTY_FUNCTION__)) | |||
1772 | "saw non-type template parameter with wrong depth")(static_cast <bool> (NTTP->getDepth() == Info.getDeducedDepth () && "saw non-type template parameter with wrong depth" ) ? void (0) : __assert_fail ("NTTP->getDepth() == Info.getDeducedDepth() && \"saw non-type template parameter with wrong depth\"" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 1772, __extension__ __PRETTY_FUNCTION__)); | |||
1773 | ||||
1774 | llvm::APSInt Noexcept(1); | |||
1775 | switch (FPA->canThrow()) { | |||
1776 | case CT_Cannot: | |||
1777 | Noexcept = 1; | |||
1778 | LLVM_FALLTHROUGH[[gnu::fallthrough]]; | |||
1779 | ||||
1780 | case CT_Can: | |||
1781 | // We give E in noexcept(E) the "deduced from array bound" treatment. | |||
1782 | // FIXME: Should we? | |||
1783 | return DeduceNonTypeTemplateArgument( | |||
1784 | S, TemplateParams, NTTP, Noexcept, S.Context.BoolTy, | |||
1785 | /*DeducedFromArrayBound=*/true, Info, Deduced); | |||
1786 | ||||
1787 | case CT_Dependent: | |||
1788 | if (Expr *ArgNoexceptExpr = FPA->getNoexceptExpr()) | |||
1789 | return DeduceNonTypeTemplateArgument( | |||
1790 | S, TemplateParams, NTTP, ArgNoexceptExpr, Info, Deduced); | |||
1791 | // Can't deduce anything from throw(T...). | |||
1792 | break; | |||
1793 | } | |||
1794 | } | |||
1795 | // FIXME: Detect non-deduced exception specification mismatches? | |||
1796 | // | |||
1797 | // Careful about [temp.deduct.call] and [temp.deduct.conv], which allow | |||
1798 | // top-level differences in noexcept-specifications. | |||
1799 | ||||
1800 | return Sema::TDK_Success; | |||
1801 | } | |||
1802 | ||||
1803 | case Type::InjectedClassName: | |||
1804 | // Treat a template's injected-class-name as if the template | |||
1805 | // specialization type had been used. | |||
1806 | ||||
1807 | // template-name<T> (where template-name refers to a class template) | |||
1808 | // template-name<i> | |||
1809 | // TT<T> | |||
1810 | // TT<i> | |||
1811 | // TT<> | |||
1812 | case Type::TemplateSpecialization: { | |||
1813 | // When Arg cannot be a derived class, we can just try to deduce template | |||
1814 | // arguments from the template-id. | |||
1815 | if (!(TDF & TDF_DerivedClass) || !A->isRecordType()) | |||
1816 | return DeduceTemplateSpecArguments(S, TemplateParams, P, A, Info, | |||
1817 | Deduced); | |||
1818 | ||||
1819 | SmallVector<DeducedTemplateArgument, 8> DeducedOrig(Deduced.begin(), | |||
1820 | Deduced.end()); | |||
1821 | ||||
1822 | auto Result = | |||
1823 | DeduceTemplateSpecArguments(S, TemplateParams, P, A, Info, Deduced); | |||
1824 | if (Result == Sema::TDK_Success) | |||
1825 | return Result; | |||
1826 | ||||
1827 | // We cannot inspect base classes as part of deduction when the type | |||
1828 | // is incomplete, so either instantiate any templates necessary to | |||
1829 | // complete the type, or skip over it if it cannot be completed. | |||
1830 | if (!S.isCompleteType(Info.getLocation(), A)) | |||
1831 | return Result; | |||
1832 | ||||
1833 | // Reset the incorrectly deduced argument from above. | |||
1834 | Deduced = DeducedOrig; | |||
1835 | ||||
1836 | // Check bases according to C++14 [temp.deduct.call] p4b3: | |||
1837 | auto BaseResult = DeduceTemplateBases(S, getCanonicalRD(A), | |||
1838 | TemplateParams, P, Info, Deduced); | |||
1839 | return BaseResult != Sema::TDK_Invalid ? BaseResult : Result; | |||
1840 | } | |||
1841 | ||||
1842 | // T type::* | |||
1843 | // T T::* | |||
1844 | // T (type::*)() | |||
1845 | // type (T::*)() | |||
1846 | // type (type::*)(T) | |||
1847 | // type (T::*)(T) | |||
1848 | // T (type::*)(T) | |||
1849 | // T (T::*)() | |||
1850 | // T (T::*)(T) | |||
1851 | case Type::MemberPointer: { | |||
1852 | const auto *MPP = P->castAs<MemberPointerType>(), | |||
1853 | *MPA = A->getAs<MemberPointerType>(); | |||
1854 | if (!MPA) | |||
1855 | return Sema::TDK_NonDeducedMismatch; | |||
1856 | ||||
1857 | QualType PPT = MPP->getPointeeType(); | |||
1858 | if (PPT->isFunctionType()) | |||
1859 | S.adjustMemberFunctionCC(PPT, /*IsStatic=*/true, | |||
1860 | /*IsCtorOrDtor=*/false, Info.getLocation()); | |||
1861 | QualType APT = MPA->getPointeeType(); | |||
1862 | if (APT->isFunctionType()) | |||
1863 | S.adjustMemberFunctionCC(APT, /*IsStatic=*/true, | |||
1864 | /*IsCtorOrDtor=*/false, Info.getLocation()); | |||
1865 | ||||
1866 | unsigned SubTDF = TDF & TDF_IgnoreQualifiers; | |||
1867 | if (auto Result = DeduceTemplateArgumentsByTypeMatch( | |||
1868 | S, TemplateParams, PPT, APT, Info, Deduced, SubTDF)) | |||
1869 | return Result; | |||
1870 | return DeduceTemplateArgumentsByTypeMatch( | |||
1871 | S, TemplateParams, QualType(MPP->getClass(), 0), | |||
1872 | QualType(MPA->getClass(), 0), Info, Deduced, SubTDF); | |||
1873 | } | |||
1874 | ||||
1875 | // (clang extension) | |||
1876 | // | |||
1877 | // type(^)(T) | |||
1878 | // T(^)() | |||
1879 | // T(^)(T) | |||
1880 | case Type::BlockPointer: { | |||
1881 | const auto *BPP = P->castAs<BlockPointerType>(), | |||
1882 | *BPA = A->getAs<BlockPointerType>(); | |||
1883 | if (!BPA) | |||
1884 | return Sema::TDK_NonDeducedMismatch; | |||
1885 | return DeduceTemplateArgumentsByTypeMatch( | |||
1886 | S, TemplateParams, BPP->getPointeeType(), BPA->getPointeeType(), Info, | |||
1887 | Deduced, 0); | |||
1888 | } | |||
1889 | ||||
1890 | // (clang extension) | |||
1891 | // | |||
1892 | // T __attribute__(((ext_vector_type(<integral constant>)))) | |||
1893 | case Type::ExtVector: { | |||
1894 | const auto *VP = P->castAs<ExtVectorType>(); | |||
1895 | QualType ElementType; | |||
1896 | if (const auto *VA = A->getAs<ExtVectorType>()) { | |||
1897 | // Make sure that the vectors have the same number of elements. | |||
1898 | if (VP->getNumElements() != VA->getNumElements()) | |||
1899 | return Sema::TDK_NonDeducedMismatch; | |||
1900 | ElementType = VA->getElementType(); | |||
1901 | } else if (const auto *VA = A->getAs<DependentSizedExtVectorType>()) { | |||
1902 | // We can't check the number of elements, since the argument has a | |||
1903 | // dependent number of elements. This can only occur during partial | |||
1904 | // ordering. | |||
1905 | ElementType = VA->getElementType(); | |||
1906 | } else { | |||
1907 | return Sema::TDK_NonDeducedMismatch; | |||
1908 | } | |||
1909 | // Perform deduction on the element types. | |||
1910 | return DeduceTemplateArgumentsByTypeMatch( | |||
1911 | S, TemplateParams, VP->getElementType(), ElementType, Info, Deduced, | |||
1912 | TDF); | |||
1913 | } | |||
1914 | ||||
1915 | case Type::DependentVector: { | |||
1916 | const auto *VP = P->castAs<DependentVectorType>(); | |||
1917 | ||||
1918 | if (const auto *VA = A->getAs<VectorType>()) { | |||
1919 | // Perform deduction on the element types. | |||
1920 | if (auto Result = DeduceTemplateArgumentsByTypeMatch( | |||
1921 | S, TemplateParams, VP->getElementType(), VA->getElementType(), | |||
1922 | Info, Deduced, TDF)) | |||
1923 | return Result; | |||
1924 | ||||
1925 | // Perform deduction on the vector size, if we can. | |||
1926 | const NonTypeTemplateParmDecl *NTTP = | |||
1927 | getDeducedParameterFromExpr(Info, VP->getSizeExpr()); | |||
1928 | if (!NTTP) | |||
1929 | return Sema::TDK_Success; | |||
1930 | ||||
1931 | llvm::APSInt ArgSize(S.Context.getTypeSize(S.Context.IntTy), false); | |||
1932 | ArgSize = VA->getNumElements(); | |||
1933 | // Note that we use the "array bound" rules here; just like in that | |||
1934 | // case, we don't have any particular type for the vector size, but | |||
1935 | // we can provide one if necessary. | |||
1936 | return DeduceNonTypeTemplateArgument(S, TemplateParams, NTTP, ArgSize, | |||
1937 | S.Context.UnsignedIntTy, true, | |||
1938 | Info, Deduced); | |||
1939 | } | |||
1940 | ||||
1941 | if (const auto *VA = A->getAs<DependentVectorType>()) { | |||
1942 | // Perform deduction on the element types. | |||
1943 | if (auto Result = DeduceTemplateArgumentsByTypeMatch( | |||
1944 | S, TemplateParams, VP->getElementType(), VA->getElementType(), | |||
1945 | Info, Deduced, TDF)) | |||
1946 | return Result; | |||
1947 | ||||
1948 | // Perform deduction on the vector size, if we can. | |||
1949 | const NonTypeTemplateParmDecl *NTTP = | |||
1950 | getDeducedParameterFromExpr(Info, VP->getSizeExpr()); | |||
1951 | if (!NTTP) | |||
1952 | return Sema::TDK_Success; | |||
1953 | ||||
1954 | return DeduceNonTypeTemplateArgument(S, TemplateParams, NTTP, | |||
1955 | VA->getSizeExpr(), Info, Deduced); | |||
1956 | } | |||
1957 | ||||
1958 | return Sema::TDK_NonDeducedMismatch; | |||
1959 | } | |||
1960 | ||||
1961 | // (clang extension) | |||
1962 | // | |||
1963 | // T __attribute__(((ext_vector_type(N)))) | |||
1964 | case Type::DependentSizedExtVector: { | |||
1965 | const auto *VP = P->castAs<DependentSizedExtVectorType>(); | |||
1966 | ||||
1967 | if (const auto *VA = A->getAs<ExtVectorType>()) { | |||
1968 | // Perform deduction on the element types. | |||
1969 | if (auto Result = DeduceTemplateArgumentsByTypeMatch( | |||
1970 | S, TemplateParams, VP->getElementType(), VA->getElementType(), | |||
1971 | Info, Deduced, TDF)) | |||
1972 | return Result; | |||
1973 | ||||
1974 | // Perform deduction on the vector size, if we can. | |||
1975 | const NonTypeTemplateParmDecl *NTTP = | |||
1976 | getDeducedParameterFromExpr(Info, VP->getSizeExpr()); | |||
1977 | if (!NTTP) | |||
1978 | return Sema::TDK_Success; | |||
1979 | ||||
1980 | llvm::APSInt ArgSize(S.Context.getTypeSize(S.Context.IntTy), false); | |||
1981 | ArgSize = VA->getNumElements(); | |||
1982 | // Note that we use the "array bound" rules here; just like in that | |||
1983 | // case, we don't have any particular type for the vector size, but | |||
1984 | // we can provide one if necessary. | |||
1985 | return DeduceNonTypeTemplateArgument(S, TemplateParams, NTTP, ArgSize, | |||
1986 | S.Context.IntTy, true, Info, | |||
1987 | Deduced); | |||
1988 | } | |||
1989 | ||||
1990 | if (const auto *VA = A->getAs<DependentSizedExtVectorType>()) { | |||
1991 | // Perform deduction on the element types. | |||
1992 | if (auto Result = DeduceTemplateArgumentsByTypeMatch( | |||
1993 | S, TemplateParams, VP->getElementType(), VA->getElementType(), | |||
1994 | Info, Deduced, TDF)) | |||
1995 | return Result; | |||
1996 | ||||
1997 | // Perform deduction on the vector size, if we can. | |||
1998 | const NonTypeTemplateParmDecl *NTTP = | |||
1999 | getDeducedParameterFromExpr(Info, VP->getSizeExpr()); | |||
2000 | if (!NTTP) | |||
2001 | return Sema::TDK_Success; | |||
2002 | ||||
2003 | return DeduceNonTypeTemplateArgument(S, TemplateParams, NTTP, | |||
2004 | VA->getSizeExpr(), Info, Deduced); | |||
2005 | } | |||
2006 | ||||
2007 | return Sema::TDK_NonDeducedMismatch; | |||
2008 | } | |||
2009 | ||||
2010 | // (clang extension) | |||
2011 | // | |||
2012 | // T __attribute__((matrix_type(<integral constant>, | |||
2013 | // <integral constant>))) | |||
2014 | case Type::ConstantMatrix: { | |||
2015 | const auto *MP = P->castAs<ConstantMatrixType>(), | |||
2016 | *MA = A->getAs<ConstantMatrixType>(); | |||
2017 | if (!MA) | |||
2018 | return Sema::TDK_NonDeducedMismatch; | |||
2019 | ||||
2020 | // Check that the dimensions are the same | |||
2021 | if (MP->getNumRows() != MA->getNumRows() || | |||
2022 | MP->getNumColumns() != MA->getNumColumns()) { | |||
2023 | return Sema::TDK_NonDeducedMismatch; | |||
2024 | } | |||
2025 | // Perform deduction on element types. | |||
2026 | return DeduceTemplateArgumentsByTypeMatch( | |||
2027 | S, TemplateParams, MP->getElementType(), MA->getElementType(), Info, | |||
2028 | Deduced, TDF); | |||
2029 | } | |||
2030 | ||||
2031 | case Type::DependentSizedMatrix: { | |||
2032 | const auto *MP = P->castAs<DependentSizedMatrixType>(); | |||
2033 | const auto *MA = A->getAs<MatrixType>(); | |||
2034 | if (!MA) | |||
2035 | return Sema::TDK_NonDeducedMismatch; | |||
2036 | ||||
2037 | // Check the element type of the matrixes. | |||
2038 | if (auto Result = DeduceTemplateArgumentsByTypeMatch( | |||
2039 | S, TemplateParams, MP->getElementType(), MA->getElementType(), | |||
2040 | Info, Deduced, TDF)) | |||
2041 | return Result; | |||
2042 | ||||
2043 | // Try to deduce a matrix dimension. | |||
2044 | auto DeduceMatrixArg = | |||
2045 | [&S, &Info, &Deduced, &TemplateParams]( | |||
2046 | Expr *ParamExpr, const MatrixType *A, | |||
2047 | unsigned (ConstantMatrixType::*GetArgDimension)() const, | |||
2048 | Expr *(DependentSizedMatrixType::*GetArgDimensionExpr)() const) { | |||
2049 | const auto *ACM = dyn_cast<ConstantMatrixType>(A); | |||
2050 | const auto *ADM = dyn_cast<DependentSizedMatrixType>(A); | |||
2051 | if (!ParamExpr->isValueDependent()) { | |||
2052 | Optional<llvm::APSInt> ParamConst = | |||
2053 | ParamExpr->getIntegerConstantExpr(S.Context); | |||
2054 | if (!ParamConst) | |||
2055 | return Sema::TDK_NonDeducedMismatch; | |||
2056 | ||||
2057 | if (ACM) { | |||
2058 | if ((ACM->*GetArgDimension)() == *ParamConst) | |||
2059 | return Sema::TDK_Success; | |||
2060 | return Sema::TDK_NonDeducedMismatch; | |||
2061 | } | |||
2062 | ||||
2063 | Expr *ArgExpr = (ADM->*GetArgDimensionExpr)(); | |||
2064 | if (Optional<llvm::APSInt> ArgConst = | |||
2065 | ArgExpr->getIntegerConstantExpr(S.Context)) | |||
2066 | if (*ArgConst == *ParamConst) | |||
2067 | return Sema::TDK_Success; | |||
2068 | return Sema::TDK_NonDeducedMismatch; | |||
2069 | } | |||
2070 | ||||
2071 | const NonTypeTemplateParmDecl *NTTP = | |||
2072 | getDeducedParameterFromExpr(Info, ParamExpr); | |||
2073 | if (!NTTP) | |||
2074 | return Sema::TDK_Success; | |||
2075 | ||||
2076 | if (ACM
| |||
2077 | llvm::APSInt ArgConst( | |||
2078 | S.Context.getTypeSize(S.Context.getSizeType())); | |||
2079 | ArgConst = (ACM->*GetArgDimension)(); | |||
2080 | return DeduceNonTypeTemplateArgument( | |||
2081 | S, TemplateParams, NTTP, ArgConst, S.Context.getSizeType(), | |||
2082 | /*ArrayBound=*/true, Info, Deduced); | |||
2083 | } | |||
2084 | ||||
2085 | return DeduceNonTypeTemplateArgument(S, TemplateParams, NTTP, | |||
2086 | (ADM->*GetArgDimensionExpr)(), | |||
| ||||
2087 | Info, Deduced); | |||
2088 | }; | |||
2089 | ||||
2090 | if (auto Result = DeduceMatrixArg(MP->getRowExpr(), MA, | |||
2091 | &ConstantMatrixType::getNumRows, | |||
2092 | &DependentSizedMatrixType::getRowExpr)) | |||
2093 | return Result; | |||
2094 | ||||
2095 | return DeduceMatrixArg(MP->getColumnExpr(), MA, | |||
2096 | &ConstantMatrixType::getNumColumns, | |||
2097 | &DependentSizedMatrixType::getColumnExpr); | |||
2098 | } | |||
2099 | ||||
2100 | // (clang extension) | |||
2101 | // | |||
2102 | // T __attribute__(((address_space(N)))) | |||
2103 | case Type::DependentAddressSpace: { | |||
2104 | const auto *ASP = P->castAs<DependentAddressSpaceType>(); | |||
2105 | ||||
2106 | if (const auto *ASA = A->getAs<DependentAddressSpaceType>()) { | |||
2107 | // Perform deduction on the pointer type. | |||
2108 | if (auto Result = DeduceTemplateArgumentsByTypeMatch( | |||
2109 | S, TemplateParams, ASP->getPointeeType(), ASA->getPointeeType(), | |||
2110 | Info, Deduced, TDF)) | |||
2111 | return Result; | |||
2112 | ||||
2113 | // Perform deduction on the address space, if we can. | |||
2114 | const NonTypeTemplateParmDecl *NTTP = | |||
2115 | getDeducedParameterFromExpr(Info, ASP->getAddrSpaceExpr()); | |||
2116 | if (!NTTP) | |||
2117 | return Sema::TDK_Success; | |||
2118 | ||||
2119 | return DeduceNonTypeTemplateArgument( | |||
2120 | S, TemplateParams, NTTP, ASA->getAddrSpaceExpr(), Info, Deduced); | |||
2121 | } | |||
2122 | ||||
2123 | if (isTargetAddressSpace(A.getAddressSpace())) { | |||
2124 | llvm::APSInt ArgAddressSpace(S.Context.getTypeSize(S.Context.IntTy), | |||
2125 | false); | |||
2126 | ArgAddressSpace = toTargetAddressSpace(A.getAddressSpace()); | |||
2127 | ||||
2128 | // Perform deduction on the pointer types. | |||
2129 | if (auto Result = DeduceTemplateArgumentsByTypeMatch( | |||
2130 | S, TemplateParams, ASP->getPointeeType(), | |||
2131 | S.Context.removeAddrSpaceQualType(A), Info, Deduced, TDF)) | |||
2132 | return Result; | |||
2133 | ||||
2134 | // Perform deduction on the address space, if we can. | |||
2135 | const NonTypeTemplateParmDecl *NTTP = | |||
2136 | getDeducedParameterFromExpr(Info, ASP->getAddrSpaceExpr()); | |||
2137 | if (!NTTP) | |||
2138 | return Sema::TDK_Success; | |||
2139 | ||||
2140 | return DeduceNonTypeTemplateArgument(S, TemplateParams, NTTP, | |||
2141 | ArgAddressSpace, S.Context.IntTy, | |||
2142 | true, Info, Deduced); | |||
2143 | } | |||
2144 | ||||
2145 | return Sema::TDK_NonDeducedMismatch; | |||
2146 | } | |||
2147 | case Type::DependentBitInt: { | |||
2148 | const auto *IP = P->castAs<DependentBitIntType>(); | |||
2149 | ||||
2150 | if (const auto *IA = A->getAs<BitIntType>()) { | |||
2151 | if (IP->isUnsigned() != IA->isUnsigned()) | |||
2152 | return Sema::TDK_NonDeducedMismatch; | |||
2153 | ||||
2154 | const NonTypeTemplateParmDecl *NTTP = | |||
2155 | getDeducedParameterFromExpr(Info, IP->getNumBitsExpr()); | |||
2156 | if (!NTTP) | |||
2157 | return Sema::TDK_Success; | |||
2158 | ||||
2159 | llvm::APSInt ArgSize(S.Context.getTypeSize(S.Context.IntTy), false); | |||
2160 | ArgSize = IA->getNumBits(); | |||
2161 | ||||
2162 | return DeduceNonTypeTemplateArgument(S, TemplateParams, NTTP, ArgSize, | |||
2163 | S.Context.IntTy, true, Info, | |||
2164 | Deduced); | |||
2165 | } | |||
2166 | ||||
2167 | if (const auto *IA = A->getAs<DependentBitIntType>()) { | |||
2168 | if (IP->isUnsigned() != IA->isUnsigned()) | |||
2169 | return Sema::TDK_NonDeducedMismatch; | |||
2170 | return Sema::TDK_Success; | |||
2171 | } | |||
2172 | ||||
2173 | return Sema::TDK_NonDeducedMismatch; | |||
2174 | } | |||
2175 | ||||
2176 | case Type::TypeOfExpr: | |||
2177 | case Type::TypeOf: | |||
2178 | case Type::DependentName: | |||
2179 | case Type::UnresolvedUsing: | |||
2180 | case Type::Decltype: | |||
2181 | case Type::UnaryTransform: | |||
2182 | case Type::DeducedTemplateSpecialization: | |||
2183 | case Type::DependentTemplateSpecialization: | |||
2184 | case Type::PackExpansion: | |||
2185 | case Type::Pipe: | |||
2186 | // No template argument deduction for these types | |||
2187 | return Sema::TDK_Success; | |||
2188 | } | |||
2189 | ||||
2190 | llvm_unreachable("Invalid Type Class!")::llvm::llvm_unreachable_internal("Invalid Type Class!", "clang/lib/Sema/SemaTemplateDeduction.cpp" , 2190); | |||
2191 | } | |||
2192 | ||||
2193 | static Sema::TemplateDeductionResult | |||
2194 | DeduceTemplateArguments(Sema &S, TemplateParameterList *TemplateParams, | |||
2195 | const TemplateArgument &P, TemplateArgument A, | |||
2196 | TemplateDeductionInfo &Info, | |||
2197 | SmallVectorImpl<DeducedTemplateArgument> &Deduced) { | |||
2198 | // If the template argument is a pack expansion, perform template argument | |||
2199 | // deduction against the pattern of that expansion. This only occurs during | |||
2200 | // partial ordering. | |||
2201 | if (A.isPackExpansion()) | |||
2202 | A = A.getPackExpansionPattern(); | |||
2203 | ||||
2204 | switch (P.getKind()) { | |||
2205 | case TemplateArgument::Null: | |||
2206 | llvm_unreachable("Null template argument in parameter list")::llvm::llvm_unreachable_internal("Null template argument in parameter list" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 2206); | |||
2207 | ||||
2208 | case TemplateArgument::Type: | |||
2209 | if (A.getKind() == TemplateArgument::Type) | |||
2210 | return DeduceTemplateArgumentsByTypeMatch( | |||
2211 | S, TemplateParams, P.getAsType(), A.getAsType(), Info, Deduced, 0); | |||
2212 | Info.FirstArg = P; | |||
2213 | Info.SecondArg = A; | |||
2214 | return Sema::TDK_NonDeducedMismatch; | |||
2215 | ||||
2216 | case TemplateArgument::Template: | |||
2217 | if (A.getKind() == TemplateArgument::Template) | |||
2218 | return DeduceTemplateArguments(S, TemplateParams, P.getAsTemplate(), | |||
2219 | A.getAsTemplate(), Info, Deduced); | |||
2220 | Info.FirstArg = P; | |||
2221 | Info.SecondArg = A; | |||
2222 | return Sema::TDK_NonDeducedMismatch; | |||
2223 | ||||
2224 | case TemplateArgument::TemplateExpansion: | |||
2225 | llvm_unreachable("caller should handle pack expansions")::llvm::llvm_unreachable_internal("caller should handle pack expansions" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 2225); | |||
2226 | ||||
2227 | case TemplateArgument::Declaration: | |||
2228 | if (A.getKind() == TemplateArgument::Declaration && | |||
2229 | isSameDeclaration(P.getAsDecl(), A.getAsDecl())) | |||
2230 | return Sema::TDK_Success; | |||
2231 | ||||
2232 | Info.FirstArg = P; | |||
2233 | Info.SecondArg = A; | |||
2234 | return Sema::TDK_NonDeducedMismatch; | |||
2235 | ||||
2236 | case TemplateArgument::NullPtr: | |||
2237 | if (A.getKind() == TemplateArgument::NullPtr && | |||
2238 | S.Context.hasSameType(P.getNullPtrType(), A.getNullPtrType())) | |||
2239 | return Sema::TDK_Success; | |||
2240 | ||||
2241 | Info.FirstArg = P; | |||
2242 | Info.SecondArg = A; | |||
2243 | return Sema::TDK_NonDeducedMismatch; | |||
2244 | ||||
2245 | case TemplateArgument::Integral: | |||
2246 | if (A.getKind() == TemplateArgument::Integral) { | |||
2247 | if (hasSameExtendedValue(P.getAsIntegral(), A.getAsIntegral())) | |||
2248 | return Sema::TDK_Success; | |||
2249 | } | |||
2250 | Info.FirstArg = P; | |||
2251 | Info.SecondArg = A; | |||
2252 | return Sema::TDK_NonDeducedMismatch; | |||
2253 | ||||
2254 | case TemplateArgument::Expression: | |||
2255 | if (const NonTypeTemplateParmDecl *NTTP = | |||
2256 | getDeducedParameterFromExpr(Info, P.getAsExpr())) { | |||
2257 | if (A.getKind() == TemplateArgument::Integral) | |||
2258 | return DeduceNonTypeTemplateArgument( | |||
2259 | S, TemplateParams, NTTP, A.getAsIntegral(), A.getIntegralType(), | |||
2260 | /*ArrayBound=*/false, Info, Deduced); | |||
2261 | if (A.getKind() == TemplateArgument::NullPtr) | |||
2262 | return DeduceNullPtrTemplateArgument(S, TemplateParams, NTTP, | |||
2263 | A.getNullPtrType(), Info, Deduced); | |||
2264 | if (A.getKind() == TemplateArgument::Expression) | |||
2265 | return DeduceNonTypeTemplateArgument(S, TemplateParams, NTTP, | |||
2266 | A.getAsExpr(), Info, Deduced); | |||
2267 | if (A.getKind() == TemplateArgument::Declaration) | |||
2268 | return DeduceNonTypeTemplateArgument( | |||
2269 | S, TemplateParams, NTTP, A.getAsDecl(), A.getParamTypeForDecl(), | |||
2270 | Info, Deduced); | |||
2271 | ||||
2272 | Info.FirstArg = P; | |||
2273 | Info.SecondArg = A; | |||
2274 | return Sema::TDK_NonDeducedMismatch; | |||
2275 | } | |||
2276 | ||||
2277 | // Can't deduce anything, but that's okay. | |||
2278 | return Sema::TDK_Success; | |||
2279 | case TemplateArgument::Pack: | |||
2280 | llvm_unreachable("Argument packs should be expanded by the caller!")::llvm::llvm_unreachable_internal("Argument packs should be expanded by the caller!" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 2280); | |||
2281 | } | |||
2282 | ||||
2283 | llvm_unreachable("Invalid TemplateArgument Kind!")::llvm::llvm_unreachable_internal("Invalid TemplateArgument Kind!" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 2283); | |||
2284 | } | |||
2285 | ||||
2286 | /// Determine whether there is a template argument to be used for | |||
2287 | /// deduction. | |||
2288 | /// | |||
2289 | /// This routine "expands" argument packs in-place, overriding its input | |||
2290 | /// parameters so that \c Args[ArgIdx] will be the available template argument. | |||
2291 | /// | |||
2292 | /// \returns true if there is another template argument (which will be at | |||
2293 | /// \c Args[ArgIdx]), false otherwise. | |||
2294 | static bool hasTemplateArgumentForDeduction(ArrayRef<TemplateArgument> &Args, | |||
2295 | unsigned &ArgIdx) { | |||
2296 | if (ArgIdx == Args.size()) | |||
2297 | return false; | |||
2298 | ||||
2299 | const TemplateArgument &Arg = Args[ArgIdx]; | |||
2300 | if (Arg.getKind() != TemplateArgument::Pack) | |||
2301 | return true; | |||
2302 | ||||
2303 | assert(ArgIdx == Args.size() - 1 && "Pack not at the end of argument list?")(static_cast <bool> (ArgIdx == Args.size() - 1 && "Pack not at the end of argument list?") ? void (0) : __assert_fail ("ArgIdx == Args.size() - 1 && \"Pack not at the end of argument list?\"" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 2303, __extension__ __PRETTY_FUNCTION__)); | |||
2304 | Args = Arg.pack_elements(); | |||
2305 | ArgIdx = 0; | |||
2306 | return ArgIdx < Args.size(); | |||
2307 | } | |||
2308 | ||||
2309 | /// Determine whether the given set of template arguments has a pack | |||
2310 | /// expansion that is not the last template argument. | |||
2311 | static bool hasPackExpansionBeforeEnd(ArrayRef<TemplateArgument> Args) { | |||
2312 | bool FoundPackExpansion = false; | |||
2313 | for (const auto &A : Args) { | |||
2314 | if (FoundPackExpansion) | |||
2315 | return true; | |||
2316 | ||||
2317 | if (A.getKind() == TemplateArgument::Pack) | |||
2318 | return hasPackExpansionBeforeEnd(A.pack_elements()); | |||
2319 | ||||
2320 | // FIXME: If this is a fixed-arity pack expansion from an outer level of | |||
2321 | // templates, it should not be treated as a pack expansion. | |||
2322 | if (A.isPackExpansion()) | |||
2323 | FoundPackExpansion = true; | |||
2324 | } | |||
2325 | ||||
2326 | return false; | |||
2327 | } | |||
2328 | ||||
2329 | static Sema::TemplateDeductionResult | |||
2330 | DeduceTemplateArguments(Sema &S, TemplateParameterList *TemplateParams, | |||
2331 | ArrayRef<TemplateArgument> Ps, | |||
2332 | ArrayRef<TemplateArgument> As, | |||
2333 | TemplateDeductionInfo &Info, | |||
2334 | SmallVectorImpl<DeducedTemplateArgument> &Deduced, | |||
2335 | bool NumberOfArgumentsMustMatch) { | |||
2336 | // C++0x [temp.deduct.type]p9: | |||
2337 | // If the template argument list of P contains a pack expansion that is not | |||
2338 | // the last template argument, the entire template argument list is a | |||
2339 | // non-deduced context. | |||
2340 | if (hasPackExpansionBeforeEnd(Ps)) | |||
2341 | return Sema::TDK_Success; | |||
2342 | ||||
2343 | // C++0x [temp.deduct.type]p9: | |||
2344 | // If P has a form that contains <T> or <i>, then each argument Pi of the | |||
2345 | // respective template argument list P is compared with the corresponding | |||
2346 | // argument Ai of the corresponding template argument list of A. | |||
2347 | unsigned ArgIdx = 0, ParamIdx = 0; | |||
2348 | for (; hasTemplateArgumentForDeduction(Ps, ParamIdx); ++ParamIdx) { | |||
2349 | const TemplateArgument &P = Ps[ParamIdx]; | |||
2350 | if (!P.isPackExpansion()) { | |||
2351 | // The simple case: deduce template arguments by matching Pi and Ai. | |||
2352 | ||||
2353 | // Check whether we have enough arguments. | |||
2354 | if (!hasTemplateArgumentForDeduction(As, ArgIdx)) | |||
2355 | return NumberOfArgumentsMustMatch | |||
2356 | ? Sema::TDK_MiscellaneousDeductionFailure | |||
2357 | : Sema::TDK_Success; | |||
2358 | ||||
2359 | // C++1z [temp.deduct.type]p9: | |||
2360 | // During partial ordering, if Ai was originally a pack expansion [and] | |||
2361 | // Pi is not a pack expansion, template argument deduction fails. | |||
2362 | if (As[ArgIdx].isPackExpansion()) | |||
2363 | return Sema::TDK_MiscellaneousDeductionFailure; | |||
2364 | ||||
2365 | // Perform deduction for this Pi/Ai pair. | |||
2366 | if (auto Result = DeduceTemplateArguments(S, TemplateParams, P, | |||
2367 | As[ArgIdx], Info, Deduced)) | |||
2368 | return Result; | |||
2369 | ||||
2370 | // Move to the next argument. | |||
2371 | ++ArgIdx; | |||
2372 | continue; | |||
2373 | } | |||
2374 | ||||
2375 | // The parameter is a pack expansion. | |||
2376 | ||||
2377 | // C++0x [temp.deduct.type]p9: | |||
2378 | // If Pi is a pack expansion, then the pattern of Pi is compared with | |||
2379 | // each remaining argument in the template argument list of A. Each | |||
2380 | // comparison deduces template arguments for subsequent positions in the | |||
2381 | // template parameter packs expanded by Pi. | |||
2382 | TemplateArgument Pattern = P.getPackExpansionPattern(); | |||
2383 | ||||
2384 | // Prepare to deduce the packs within the pattern. | |||
2385 | PackDeductionScope PackScope(S, TemplateParams, Deduced, Info, Pattern); | |||
2386 | ||||
2387 | // Keep track of the deduced template arguments for each parameter pack | |||
2388 | // expanded by this pack expansion (the outer index) and for each | |||
2389 | // template argument (the inner SmallVectors). | |||
2390 | for (; hasTemplateArgumentForDeduction(As, ArgIdx) && | |||
2391 | PackScope.hasNextElement(); | |||
2392 | ++ArgIdx) { | |||
2393 | // Deduce template arguments from the pattern. | |||
2394 | if (auto Result = DeduceTemplateArguments(S, TemplateParams, Pattern, | |||
2395 | As[ArgIdx], Info, Deduced)) | |||
2396 | return Result; | |||
2397 | ||||
2398 | PackScope.nextPackElement(); | |||
2399 | } | |||
2400 | ||||
2401 | // Build argument packs for each of the parameter packs expanded by this | |||
2402 | // pack expansion. | |||
2403 | if (auto Result = PackScope.finish()) | |||
2404 | return Result; | |||
2405 | } | |||
2406 | ||||
2407 | return Sema::TDK_Success; | |||
2408 | } | |||
2409 | ||||
2410 | static Sema::TemplateDeductionResult | |||
2411 | DeduceTemplateArguments(Sema &S, TemplateParameterList *TemplateParams, | |||
2412 | const TemplateArgumentList &ParamList, | |||
2413 | const TemplateArgumentList &ArgList, | |||
2414 | TemplateDeductionInfo &Info, | |||
2415 | SmallVectorImpl<DeducedTemplateArgument> &Deduced) { | |||
2416 | return DeduceTemplateArguments(S, TemplateParams, ParamList.asArray(), | |||
2417 | ArgList.asArray(), Info, Deduced, | |||
2418 | /*NumberOfArgumentsMustMatch=*/false); | |||
2419 | } | |||
2420 | ||||
2421 | /// Determine whether two template arguments are the same. | |||
2422 | static bool isSameTemplateArg(ASTContext &Context, | |||
2423 | TemplateArgument X, | |||
2424 | const TemplateArgument &Y, | |||
2425 | bool PackExpansionMatchesPack = false) { | |||
2426 | // If we're checking deduced arguments (X) against original arguments (Y), | |||
2427 | // we will have flattened packs to non-expansions in X. | |||
2428 | if (PackExpansionMatchesPack && X.isPackExpansion() && !Y.isPackExpansion()) | |||
2429 | X = X.getPackExpansionPattern(); | |||
2430 | ||||
2431 | if (X.getKind() != Y.getKind()) | |||
2432 | return false; | |||
2433 | ||||
2434 | switch (X.getKind()) { | |||
2435 | case TemplateArgument::Null: | |||
2436 | llvm_unreachable("Comparing NULL template argument")::llvm::llvm_unreachable_internal("Comparing NULL template argument" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 2436); | |||
2437 | ||||
2438 | case TemplateArgument::Type: | |||
2439 | return Context.getCanonicalType(X.getAsType()) == | |||
2440 | Context.getCanonicalType(Y.getAsType()); | |||
2441 | ||||
2442 | case TemplateArgument::Declaration: | |||
2443 | return isSameDeclaration(X.getAsDecl(), Y.getAsDecl()); | |||
2444 | ||||
2445 | case TemplateArgument::NullPtr: | |||
2446 | return Context.hasSameType(X.getNullPtrType(), Y.getNullPtrType()); | |||
2447 | ||||
2448 | case TemplateArgument::Template: | |||
2449 | case TemplateArgument::TemplateExpansion: | |||
2450 | return Context.getCanonicalTemplateName( | |||
2451 | X.getAsTemplateOrTemplatePattern()).getAsVoidPointer() == | |||
2452 | Context.getCanonicalTemplateName( | |||
2453 | Y.getAsTemplateOrTemplatePattern()).getAsVoidPointer(); | |||
2454 | ||||
2455 | case TemplateArgument::Integral: | |||
2456 | return hasSameExtendedValue(X.getAsIntegral(), Y.getAsIntegral()); | |||
2457 | ||||
2458 | case TemplateArgument::Expression: { | |||
2459 | llvm::FoldingSetNodeID XID, YID; | |||
2460 | X.getAsExpr()->Profile(XID, Context, true); | |||
2461 | Y.getAsExpr()->Profile(YID, Context, true); | |||
2462 | return XID == YID; | |||
2463 | } | |||
2464 | ||||
2465 | case TemplateArgument::Pack: | |||
2466 | if (X.pack_size() != Y.pack_size()) | |||
2467 | return false; | |||
2468 | ||||
2469 | for (TemplateArgument::pack_iterator XP = X.pack_begin(), | |||
2470 | XPEnd = X.pack_end(), | |||
2471 | YP = Y.pack_begin(); | |||
2472 | XP != XPEnd; ++XP, ++YP) | |||
2473 | if (!isSameTemplateArg(Context, *XP, *YP, PackExpansionMatchesPack)) | |||
2474 | return false; | |||
2475 | ||||
2476 | return true; | |||
2477 | } | |||
2478 | ||||
2479 | llvm_unreachable("Invalid TemplateArgument Kind!")::llvm::llvm_unreachable_internal("Invalid TemplateArgument Kind!" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 2479); | |||
2480 | } | |||
2481 | ||||
2482 | /// Allocate a TemplateArgumentLoc where all locations have | |||
2483 | /// been initialized to the given location. | |||
2484 | /// | |||
2485 | /// \param Arg The template argument we are producing template argument | |||
2486 | /// location information for. | |||
2487 | /// | |||
2488 | /// \param NTTPType For a declaration template argument, the type of | |||
2489 | /// the non-type template parameter that corresponds to this template | |||
2490 | /// argument. Can be null if no type sugar is available to add to the | |||
2491 | /// type from the template argument. | |||
2492 | /// | |||
2493 | /// \param Loc The source location to use for the resulting template | |||
2494 | /// argument. | |||
2495 | TemplateArgumentLoc | |||
2496 | Sema::getTrivialTemplateArgumentLoc(const TemplateArgument &Arg, | |||
2497 | QualType NTTPType, SourceLocation Loc) { | |||
2498 | switch (Arg.getKind()) { | |||
2499 | case TemplateArgument::Null: | |||
2500 | llvm_unreachable("Can't get a NULL template argument here")::llvm::llvm_unreachable_internal("Can't get a NULL template argument here" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 2500); | |||
2501 | ||||
2502 | case TemplateArgument::Type: | |||
2503 | return TemplateArgumentLoc( | |||
2504 | Arg, Context.getTrivialTypeSourceInfo(Arg.getAsType(), Loc)); | |||
2505 | ||||
2506 | case TemplateArgument::Declaration: { | |||
2507 | if (NTTPType.isNull()) | |||
2508 | NTTPType = Arg.getParamTypeForDecl(); | |||
2509 | Expr *E = BuildExpressionFromDeclTemplateArgument(Arg, NTTPType, Loc) | |||
2510 | .getAs<Expr>(); | |||
2511 | return TemplateArgumentLoc(TemplateArgument(E), E); | |||
2512 | } | |||
2513 | ||||
2514 | case TemplateArgument::NullPtr: { | |||
2515 | if (NTTPType.isNull()) | |||
2516 | NTTPType = Arg.getNullPtrType(); | |||
2517 | Expr *E = BuildExpressionFromDeclTemplateArgument(Arg, NTTPType, Loc) | |||
2518 | .getAs<Expr>(); | |||
2519 | return TemplateArgumentLoc(TemplateArgument(NTTPType, /*isNullPtr*/true), | |||
2520 | E); | |||
2521 | } | |||
2522 | ||||
2523 | case TemplateArgument::Integral: { | |||
2524 | Expr *E = | |||
2525 | BuildExpressionFromIntegralTemplateArgument(Arg, Loc).getAs<Expr>(); | |||
2526 | return TemplateArgumentLoc(TemplateArgument(E), E); | |||
2527 | } | |||
2528 | ||||
2529 | case TemplateArgument::Template: | |||
2530 | case TemplateArgument::TemplateExpansion: { | |||
2531 | NestedNameSpecifierLocBuilder Builder; | |||
2532 | TemplateName Template = Arg.getAsTemplateOrTemplatePattern(); | |||
2533 | if (DependentTemplateName *DTN = Template.getAsDependentTemplateName()) | |||
2534 | Builder.MakeTrivial(Context, DTN->getQualifier(), Loc); | |||
2535 | else if (QualifiedTemplateName *QTN = | |||
2536 | Template.getAsQualifiedTemplateName()) | |||
2537 | Builder.MakeTrivial(Context, QTN->getQualifier(), Loc); | |||
2538 | ||||
2539 | if (Arg.getKind() == TemplateArgument::Template) | |||
2540 | return TemplateArgumentLoc(Context, Arg, | |||
2541 | Builder.getWithLocInContext(Context), Loc); | |||
2542 | ||||
2543 | return TemplateArgumentLoc( | |||
2544 | Context, Arg, Builder.getWithLocInContext(Context), Loc, Loc); | |||
2545 | } | |||
2546 | ||||
2547 | case TemplateArgument::Expression: | |||
2548 | return TemplateArgumentLoc(Arg, Arg.getAsExpr()); | |||
2549 | ||||
2550 | case TemplateArgument::Pack: | |||
2551 | return TemplateArgumentLoc(Arg, TemplateArgumentLocInfo()); | |||
2552 | } | |||
2553 | ||||
2554 | llvm_unreachable("Invalid TemplateArgument Kind!")::llvm::llvm_unreachable_internal("Invalid TemplateArgument Kind!" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 2554); | |||
2555 | } | |||
2556 | ||||
2557 | TemplateArgumentLoc | |||
2558 | Sema::getIdentityTemplateArgumentLoc(NamedDecl *TemplateParm, | |||
2559 | SourceLocation Location) { | |||
2560 | return getTrivialTemplateArgumentLoc( | |||
2561 | Context.getInjectedTemplateArg(TemplateParm), QualType(), Location); | |||
2562 | } | |||
2563 | ||||
2564 | /// Convert the given deduced template argument and add it to the set of | |||
2565 | /// fully-converted template arguments. | |||
2566 | static bool | |||
2567 | ConvertDeducedTemplateArgument(Sema &S, NamedDecl *Param, | |||
2568 | DeducedTemplateArgument Arg, | |||
2569 | NamedDecl *Template, | |||
2570 | TemplateDeductionInfo &Info, | |||
2571 | bool IsDeduced, | |||
2572 | SmallVectorImpl<TemplateArgument> &Output) { | |||
2573 | auto ConvertArg = [&](DeducedTemplateArgument Arg, | |||
2574 | unsigned ArgumentPackIndex) { | |||
2575 | // Convert the deduced template argument into a template | |||
2576 | // argument that we can check, almost as if the user had written | |||
2577 | // the template argument explicitly. | |||
2578 | TemplateArgumentLoc ArgLoc = | |||
2579 | S.getTrivialTemplateArgumentLoc(Arg, QualType(), Info.getLocation()); | |||
2580 | ||||
2581 | // Check the template argument, converting it as necessary. | |||
2582 | return S.CheckTemplateArgument( | |||
2583 | Param, ArgLoc, Template, Template->getLocation(), | |||
2584 | Template->getSourceRange().getEnd(), ArgumentPackIndex, Output, | |||
2585 | IsDeduced | |||
2586 | ? (Arg.wasDeducedFromArrayBound() ? Sema::CTAK_DeducedFromArrayBound | |||
2587 | : Sema::CTAK_Deduced) | |||
2588 | : Sema::CTAK_Specified); | |||
2589 | }; | |||
2590 | ||||
2591 | if (Arg.getKind() == TemplateArgument::Pack) { | |||
2592 | // This is a template argument pack, so check each of its arguments against | |||
2593 | // the template parameter. | |||
2594 | SmallVector<TemplateArgument, 2> PackedArgsBuilder; | |||
2595 | for (const auto &P : Arg.pack_elements()) { | |||
2596 | // When converting the deduced template argument, append it to the | |||
2597 | // general output list. We need to do this so that the template argument | |||
2598 | // checking logic has all of the prior template arguments available. | |||
2599 | DeducedTemplateArgument InnerArg(P); | |||
2600 | InnerArg.setDeducedFromArrayBound(Arg.wasDeducedFromArrayBound()); | |||
2601 | assert(InnerArg.getKind() != TemplateArgument::Pack &&(static_cast <bool> (InnerArg.getKind() != TemplateArgument ::Pack && "deduced nested pack") ? void (0) : __assert_fail ("InnerArg.getKind() != TemplateArgument::Pack && \"deduced nested pack\"" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 2602, __extension__ __PRETTY_FUNCTION__)) | |||
2602 | "deduced nested pack")(static_cast <bool> (InnerArg.getKind() != TemplateArgument ::Pack && "deduced nested pack") ? void (0) : __assert_fail ("InnerArg.getKind() != TemplateArgument::Pack && \"deduced nested pack\"" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 2602, __extension__ __PRETTY_FUNCTION__)); | |||
2603 | if (P.isNull()) { | |||
2604 | // We deduced arguments for some elements of this pack, but not for | |||
2605 | // all of them. This happens if we get a conditionally-non-deduced | |||
2606 | // context in a pack expansion (such as an overload set in one of the | |||
2607 | // arguments). | |||
2608 | S.Diag(Param->getLocation(), | |||
2609 | diag::err_template_arg_deduced_incomplete_pack) | |||
2610 | << Arg << Param; | |||
2611 | return true; | |||
2612 | } | |||
2613 | if (ConvertArg(InnerArg, PackedArgsBuilder.size())) | |||
2614 | return true; | |||
2615 | ||||
2616 | // Move the converted template argument into our argument pack. | |||
2617 | PackedArgsBuilder.push_back(Output.pop_back_val()); | |||
2618 | } | |||
2619 | ||||
2620 | // If the pack is empty, we still need to substitute into the parameter | |||
2621 | // itself, in case that substitution fails. | |||
2622 | if (PackedArgsBuilder.empty()) { | |||
2623 | LocalInstantiationScope Scope(S); | |||
2624 | TemplateArgumentList TemplateArgs(TemplateArgumentList::OnStack, Output); | |||
2625 | MultiLevelTemplateArgumentList Args(TemplateArgs); | |||
2626 | ||||
2627 | if (auto *NTTP = dyn_cast<NonTypeTemplateParmDecl>(Param)) { | |||
2628 | Sema::InstantiatingTemplate Inst(S, Template->getLocation(), Template, | |||
2629 | NTTP, Output, | |||
2630 | Template->getSourceRange()); | |||
2631 | if (Inst.isInvalid() || | |||
2632 | S.SubstType(NTTP->getType(), Args, NTTP->getLocation(), | |||
2633 | NTTP->getDeclName()).isNull()) | |||
2634 | return true; | |||
2635 | } else if (auto *TTP = dyn_cast<TemplateTemplateParmDecl>(Param)) { | |||
2636 | Sema::InstantiatingTemplate Inst(S, Template->getLocation(), Template, | |||
2637 | TTP, Output, | |||
2638 | Template->getSourceRange()); | |||
2639 | if (Inst.isInvalid() || !S.SubstDecl(TTP, S.CurContext, Args)) | |||
2640 | return true; | |||
2641 | } | |||
2642 | // For type parameters, no substitution is ever required. | |||
2643 | } | |||
2644 | ||||
2645 | // Create the resulting argument pack. | |||
2646 | Output.push_back( | |||
2647 | TemplateArgument::CreatePackCopy(S.Context, PackedArgsBuilder)); | |||
2648 | return false; | |||
2649 | } | |||
2650 | ||||
2651 | return ConvertArg(Arg, 0); | |||
2652 | } | |||
2653 | ||||
2654 | // FIXME: This should not be a template, but | |||
2655 | // ClassTemplatePartialSpecializationDecl sadly does not derive from | |||
2656 | // TemplateDecl. | |||
2657 | template<typename TemplateDeclT> | |||
2658 | static Sema::TemplateDeductionResult ConvertDeducedTemplateArguments( | |||
2659 | Sema &S, TemplateDeclT *Template, bool IsDeduced, | |||
2660 | SmallVectorImpl<DeducedTemplateArgument> &Deduced, | |||
2661 | TemplateDeductionInfo &Info, SmallVectorImpl<TemplateArgument> &Builder, | |||
2662 | LocalInstantiationScope *CurrentInstantiationScope = nullptr, | |||
2663 | unsigned NumAlreadyConverted = 0, bool PartialOverloading = false) { | |||
2664 | TemplateParameterList *TemplateParams = Template->getTemplateParameters(); | |||
2665 | ||||
2666 | for (unsigned I = 0, N = TemplateParams->size(); I != N; ++I) { | |||
2667 | NamedDecl *Param = TemplateParams->getParam(I); | |||
2668 | ||||
2669 | // C++0x [temp.arg.explicit]p3: | |||
2670 | // A trailing template parameter pack (14.5.3) not otherwise deduced will | |||
2671 | // be deduced to an empty sequence of template arguments. | |||
2672 | // FIXME: Where did the word "trailing" come from? | |||
2673 | if (Deduced[I].isNull() && Param->isTemplateParameterPack()) { | |||
2674 | if (auto Result = | |||
2675 | PackDeductionScope(S, TemplateParams, Deduced, Info, I).finish()) | |||
2676 | return Result; | |||
2677 | } | |||
2678 | ||||
2679 | if (!Deduced[I].isNull()) { | |||
2680 | if (I < NumAlreadyConverted) { | |||
2681 | // We may have had explicitly-specified template arguments for a | |||
2682 | // template parameter pack (that may or may not have been extended | |||
2683 | // via additional deduced arguments). | |||
2684 | if (Param->isParameterPack() && CurrentInstantiationScope && | |||
2685 | CurrentInstantiationScope->getPartiallySubstitutedPack() == Param) { | |||
2686 | // Forget the partially-substituted pack; its substitution is now | |||
2687 | // complete. | |||
2688 | CurrentInstantiationScope->ResetPartiallySubstitutedPack(); | |||
2689 | // We still need to check the argument in case it was extended by | |||
2690 | // deduction. | |||
2691 | } else { | |||
2692 | // We have already fully type-checked and converted this | |||
2693 | // argument, because it was explicitly-specified. Just record the | |||
2694 | // presence of this argument. | |||
2695 | Builder.push_back(Deduced[I]); | |||
2696 | continue; | |||
2697 | } | |||
2698 | } | |||
2699 | ||||
2700 | // We may have deduced this argument, so it still needs to be | |||
2701 | // checked and converted. | |||
2702 | if (ConvertDeducedTemplateArgument(S, Param, Deduced[I], Template, Info, | |||
2703 | IsDeduced, Builder)) { | |||
2704 | Info.Param = makeTemplateParameter(Param); | |||
2705 | // FIXME: These template arguments are temporary. Free them! | |||
2706 | Info.reset(TemplateArgumentList::CreateCopy(S.Context, Builder)); | |||
2707 | return Sema::TDK_SubstitutionFailure; | |||
2708 | } | |||
2709 | ||||
2710 | continue; | |||
2711 | } | |||
2712 | ||||
2713 | // Substitute into the default template argument, if available. | |||
2714 | bool HasDefaultArg = false; | |||
2715 | TemplateDecl *TD = dyn_cast<TemplateDecl>(Template); | |||
2716 | if (!TD) { | |||
2717 | assert(isa<ClassTemplatePartialSpecializationDecl>(Template) ||(static_cast <bool> (isa<ClassTemplatePartialSpecializationDecl >(Template) || isa<VarTemplatePartialSpecializationDecl >(Template)) ? void (0) : __assert_fail ("isa<ClassTemplatePartialSpecializationDecl>(Template) || isa<VarTemplatePartialSpecializationDecl>(Template)" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 2718, __extension__ __PRETTY_FUNCTION__)) | |||
2718 | isa<VarTemplatePartialSpecializationDecl>(Template))(static_cast <bool> (isa<ClassTemplatePartialSpecializationDecl >(Template) || isa<VarTemplatePartialSpecializationDecl >(Template)) ? void (0) : __assert_fail ("isa<ClassTemplatePartialSpecializationDecl>(Template) || isa<VarTemplatePartialSpecializationDecl>(Template)" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 2718, __extension__ __PRETTY_FUNCTION__)); | |||
2719 | return Sema::TDK_Incomplete; | |||
2720 | } | |||
2721 | ||||
2722 | TemplateArgumentLoc DefArg; | |||
2723 | { | |||
2724 | Qualifiers ThisTypeQuals; | |||
2725 | CXXRecordDecl *ThisContext = nullptr; | |||
2726 | if (auto *Rec = dyn_cast<CXXRecordDecl>(TD->getDeclContext())) | |||
2727 | if (Rec->isLambda()) | |||
2728 | if (auto *Method = dyn_cast<CXXMethodDecl>(Rec->getDeclContext())) { | |||
2729 | ThisContext = Method->getParent(); | |||
2730 | ThisTypeQuals = Method->getMethodQualifiers(); | |||
2731 | } | |||
2732 | ||||
2733 | Sema::CXXThisScopeRAII ThisScope(S, ThisContext, ThisTypeQuals, | |||
2734 | S.getLangOpts().CPlusPlus17); | |||
2735 | ||||
2736 | DefArg = S.SubstDefaultTemplateArgumentIfAvailable( | |||
2737 | TD, TD->getLocation(), TD->getSourceRange().getEnd(), Param, Builder, | |||
2738 | HasDefaultArg); | |||
2739 | } | |||
2740 | ||||
2741 | // If there was no default argument, deduction is incomplete. | |||
2742 | if (DefArg.getArgument().isNull()) { | |||
2743 | Info.Param = makeTemplateParameter( | |||
2744 | const_cast<NamedDecl *>(TemplateParams->getParam(I))); | |||
2745 | Info.reset(TemplateArgumentList::CreateCopy(S.Context, Builder)); | |||
2746 | if (PartialOverloading) break; | |||
2747 | ||||
2748 | return HasDefaultArg ? Sema::TDK_SubstitutionFailure | |||
2749 | : Sema::TDK_Incomplete; | |||
2750 | } | |||
2751 | ||||
2752 | // Check whether we can actually use the default argument. | |||
2753 | if (S.CheckTemplateArgument(Param, DefArg, TD, TD->getLocation(), | |||
2754 | TD->getSourceRange().getEnd(), 0, Builder, | |||
2755 | Sema::CTAK_Specified)) { | |||
2756 | Info.Param = makeTemplateParameter( | |||
2757 | const_cast<NamedDecl *>(TemplateParams->getParam(I))); | |||
2758 | // FIXME: These template arguments are temporary. Free them! | |||
2759 | Info.reset(TemplateArgumentList::CreateCopy(S.Context, Builder)); | |||
2760 | return Sema::TDK_SubstitutionFailure; | |||
2761 | } | |||
2762 | ||||
2763 | // If we get here, we successfully used the default template argument. | |||
2764 | } | |||
2765 | ||||
2766 | return Sema::TDK_Success; | |||
2767 | } | |||
2768 | ||||
2769 | static DeclContext *getAsDeclContextOrEnclosing(Decl *D) { | |||
2770 | if (auto *DC = dyn_cast<DeclContext>(D)) | |||
2771 | return DC; | |||
2772 | return D->getDeclContext(); | |||
2773 | } | |||
2774 | ||||
2775 | template<typename T> struct IsPartialSpecialization { | |||
2776 | static constexpr bool value = false; | |||
2777 | }; | |||
2778 | template<> | |||
2779 | struct IsPartialSpecialization<ClassTemplatePartialSpecializationDecl> { | |||
2780 | static constexpr bool value = true; | |||
2781 | }; | |||
2782 | template<> | |||
2783 | struct IsPartialSpecialization<VarTemplatePartialSpecializationDecl> { | |||
2784 | static constexpr bool value = true; | |||
2785 | }; | |||
2786 | ||||
2787 | template<typename TemplateDeclT> | |||
2788 | static Sema::TemplateDeductionResult | |||
2789 | CheckDeducedArgumentConstraints(Sema& S, TemplateDeclT *Template, | |||
2790 | ArrayRef<TemplateArgument> DeducedArgs, | |||
2791 | TemplateDeductionInfo& Info) { | |||
2792 | llvm::SmallVector<const Expr *, 3> AssociatedConstraints; | |||
2793 | Template->getAssociatedConstraints(AssociatedConstraints); | |||
2794 | if (S.CheckConstraintSatisfaction(Template, AssociatedConstraints, | |||
2795 | DeducedArgs, Info.getLocation(), | |||
2796 | Info.AssociatedConstraintsSatisfaction) || | |||
2797 | !Info.AssociatedConstraintsSatisfaction.IsSatisfied) { | |||
2798 | Info.reset(TemplateArgumentList::CreateCopy(S.Context, DeducedArgs)); | |||
2799 | return Sema::TDK_ConstraintsNotSatisfied; | |||
2800 | } | |||
2801 | return Sema::TDK_Success; | |||
2802 | } | |||
2803 | ||||
2804 | /// Complete template argument deduction for a partial specialization. | |||
2805 | template <typename T> | |||
2806 | static std::enable_if_t<IsPartialSpecialization<T>::value, | |||
2807 | Sema::TemplateDeductionResult> | |||
2808 | FinishTemplateArgumentDeduction( | |||
2809 | Sema &S, T *Partial, bool IsPartialOrdering, | |||
2810 | const TemplateArgumentList &TemplateArgs, | |||
2811 | SmallVectorImpl<DeducedTemplateArgument> &Deduced, | |||
2812 | TemplateDeductionInfo &Info) { | |||
2813 | // Unevaluated SFINAE context. | |||
2814 | EnterExpressionEvaluationContext Unevaluated( | |||
2815 | S, Sema::ExpressionEvaluationContext::Unevaluated); | |||
2816 | Sema::SFINAETrap Trap(S); | |||
2817 | ||||
2818 | Sema::ContextRAII SavedContext(S, getAsDeclContextOrEnclosing(Partial)); | |||
2819 | ||||
2820 | // C++ [temp.deduct.type]p2: | |||
2821 | // [...] or if any template argument remains neither deduced nor | |||
2822 | // explicitly specified, template argument deduction fails. | |||
2823 | SmallVector<TemplateArgument, 4> Builder; | |||
2824 | if (auto Result = ConvertDeducedTemplateArguments( | |||
2825 | S, Partial, IsPartialOrdering, Deduced, Info, Builder)) | |||
2826 | return Result; | |||
2827 | ||||
2828 | // Form the template argument list from the deduced template arguments. | |||
2829 | TemplateArgumentList *DeducedArgumentList | |||
2830 | = TemplateArgumentList::CreateCopy(S.Context, Builder); | |||
2831 | ||||
2832 | Info.reset(DeducedArgumentList); | |||
2833 | ||||
2834 | // Substitute the deduced template arguments into the template | |||
2835 | // arguments of the class template partial specialization, and | |||
2836 | // verify that the instantiated template arguments are both valid | |||
2837 | // and are equivalent to the template arguments originally provided | |||
2838 | // to the class template. | |||
2839 | LocalInstantiationScope InstScope(S); | |||
2840 | auto *Template = Partial->getSpecializedTemplate(); | |||
2841 | const ASTTemplateArgumentListInfo *PartialTemplArgInfo = | |||
2842 | Partial->getTemplateArgsAsWritten(); | |||
2843 | ||||
2844 | TemplateArgumentListInfo InstArgs(PartialTemplArgInfo->LAngleLoc, | |||
2845 | PartialTemplArgInfo->RAngleLoc); | |||
2846 | ||||
2847 | if (S.SubstTemplateArguments( | |||
2848 | PartialTemplArgInfo->arguments(), | |||
2849 | MultiLevelTemplateArgumentList(*DeducedArgumentList), InstArgs)) { | |||
2850 | unsigned ArgIdx = InstArgs.size(), ParamIdx = ArgIdx; | |||
2851 | if (ParamIdx >= Partial->getTemplateParameters()->size()) | |||
2852 | ParamIdx = Partial->getTemplateParameters()->size() - 1; | |||
2853 | ||||
2854 | Decl *Param = const_cast<NamedDecl *>( | |||
2855 | Partial->getTemplateParameters()->getParam(ParamIdx)); | |||
2856 | Info.Param = makeTemplateParameter(Param); | |||
2857 | Info.FirstArg = (*PartialTemplArgInfo)[ArgIdx].getArgument(); | |||
2858 | return Sema::TDK_SubstitutionFailure; | |||
2859 | } | |||
2860 | ||||
2861 | bool ConstraintsNotSatisfied; | |||
2862 | SmallVector<TemplateArgument, 4> ConvertedInstArgs; | |||
2863 | if (S.CheckTemplateArgumentList(Template, Partial->getLocation(), InstArgs, | |||
2864 | false, ConvertedInstArgs, | |||
2865 | /*UpdateArgsWithConversions=*/true, | |||
2866 | &ConstraintsNotSatisfied)) | |||
2867 | return ConstraintsNotSatisfied ? Sema::TDK_ConstraintsNotSatisfied : | |||
2868 | Sema::TDK_SubstitutionFailure; | |||
2869 | ||||
2870 | TemplateParameterList *TemplateParams = Template->getTemplateParameters(); | |||
2871 | for (unsigned I = 0, E = TemplateParams->size(); I != E; ++I) { | |||
2872 | TemplateArgument InstArg = ConvertedInstArgs.data()[I]; | |||
2873 | if (!isSameTemplateArg(S.Context, TemplateArgs[I], InstArg)) { | |||
2874 | Info.Param = makeTemplateParameter(TemplateParams->getParam(I)); | |||
2875 | Info.FirstArg = TemplateArgs[I]; | |||
2876 | Info.SecondArg = InstArg; | |||
2877 | return Sema::TDK_NonDeducedMismatch; | |||
2878 | } | |||
2879 | } | |||
2880 | ||||
2881 | if (Trap.hasErrorOccurred()) | |||
2882 | return Sema::TDK_SubstitutionFailure; | |||
2883 | ||||
2884 | if (auto Result = CheckDeducedArgumentConstraints(S, Partial, Builder, Info)) | |||
2885 | return Result; | |||
2886 | ||||
2887 | return Sema::TDK_Success; | |||
2888 | } | |||
2889 | ||||
2890 | /// Complete template argument deduction for a class or variable template, | |||
2891 | /// when partial ordering against a partial specialization. | |||
2892 | // FIXME: Factor out duplication with partial specialization version above. | |||
2893 | static Sema::TemplateDeductionResult FinishTemplateArgumentDeduction( | |||
2894 | Sema &S, TemplateDecl *Template, bool PartialOrdering, | |||
2895 | const TemplateArgumentList &TemplateArgs, | |||
2896 | SmallVectorImpl<DeducedTemplateArgument> &Deduced, | |||
2897 | TemplateDeductionInfo &Info) { | |||
2898 | // Unevaluated SFINAE context. | |||
2899 | EnterExpressionEvaluationContext Unevaluated( | |||
2900 | S, Sema::ExpressionEvaluationContext::Unevaluated); | |||
2901 | Sema::SFINAETrap Trap(S); | |||
2902 | ||||
2903 | Sema::ContextRAII SavedContext(S, getAsDeclContextOrEnclosing(Template)); | |||
2904 | ||||
2905 | // C++ [temp.deduct.type]p2: | |||
2906 | // [...] or if any template argument remains neither deduced nor | |||
2907 | // explicitly specified, template argument deduction fails. | |||
2908 | SmallVector<TemplateArgument, 4> Builder; | |||
2909 | if (auto Result = ConvertDeducedTemplateArguments( | |||
2910 | S, Template, /*IsDeduced*/PartialOrdering, Deduced, Info, Builder)) | |||
2911 | return Result; | |||
2912 | ||||
2913 | // Check that we produced the correct argument list. | |||
2914 | TemplateParameterList *TemplateParams = Template->getTemplateParameters(); | |||
2915 | for (unsigned I = 0, E = TemplateParams->size(); I != E; ++I) { | |||
2916 | TemplateArgument InstArg = Builder[I]; | |||
2917 | if (!isSameTemplateArg(S.Context, TemplateArgs[I], InstArg, | |||
2918 | /*PackExpansionMatchesPack*/true)) { | |||
2919 | Info.Param = makeTemplateParameter(TemplateParams->getParam(I)); | |||
2920 | Info.FirstArg = TemplateArgs[I]; | |||
2921 | Info.SecondArg = InstArg; | |||
2922 | return Sema::TDK_NonDeducedMismatch; | |||
2923 | } | |||
2924 | } | |||
2925 | ||||
2926 | if (Trap.hasErrorOccurred()) | |||
2927 | return Sema::TDK_SubstitutionFailure; | |||
2928 | ||||
2929 | if (auto Result = CheckDeducedArgumentConstraints(S, Template, Builder, | |||
2930 | Info)) | |||
2931 | return Result; | |||
2932 | ||||
2933 | return Sema::TDK_Success; | |||
2934 | } | |||
2935 | ||||
2936 | /// Perform template argument deduction to determine whether | |||
2937 | /// the given template arguments match the given class template | |||
2938 | /// partial specialization per C++ [temp.class.spec.match]. | |||
2939 | Sema::TemplateDeductionResult | |||
2940 | Sema::DeduceTemplateArguments(ClassTemplatePartialSpecializationDecl *Partial, | |||
2941 | const TemplateArgumentList &TemplateArgs, | |||
2942 | TemplateDeductionInfo &Info) { | |||
2943 | if (Partial->isInvalidDecl()) | |||
2944 | return TDK_Invalid; | |||
2945 | ||||
2946 | // C++ [temp.class.spec.match]p2: | |||
2947 | // A partial specialization matches a given actual template | |||
2948 | // argument list if the template arguments of the partial | |||
2949 | // specialization can be deduced from the actual template argument | |||
2950 | // list (14.8.2). | |||
2951 | ||||
2952 | // Unevaluated SFINAE context. | |||
2953 | EnterExpressionEvaluationContext Unevaluated( | |||
2954 | *this, Sema::ExpressionEvaluationContext::Unevaluated); | |||
2955 | SFINAETrap Trap(*this); | |||
2956 | ||||
2957 | // This deduction has no relation to any outer instantiation we might be | |||
2958 | // performing. | |||
2959 | LocalInstantiationScope InstantiationScope(*this); | |||
2960 | ||||
2961 | SmallVector<DeducedTemplateArgument, 4> Deduced; | |||
2962 | Deduced.resize(Partial->getTemplateParameters()->size()); | |||
2963 | if (TemplateDeductionResult Result | |||
2964 | = ::DeduceTemplateArguments(*this, | |||
2965 | Partial->getTemplateParameters(), | |||
2966 | Partial->getTemplateArgs(), | |||
2967 | TemplateArgs, Info, Deduced)) | |||
2968 | return Result; | |||
2969 | ||||
2970 | SmallVector<TemplateArgument, 4> DeducedArgs(Deduced.begin(), Deduced.end()); | |||
2971 | InstantiatingTemplate Inst(*this, Info.getLocation(), Partial, DeducedArgs, | |||
2972 | Info); | |||
2973 | if (Inst.isInvalid()) | |||
2974 | return TDK_InstantiationDepth; | |||
2975 | ||||
2976 | if (Trap.hasErrorOccurred()) | |||
2977 | return Sema::TDK_SubstitutionFailure; | |||
2978 | ||||
2979 | TemplateDeductionResult Result; | |||
2980 | runWithSufficientStackSpace(Info.getLocation(), [&] { | |||
2981 | Result = ::FinishTemplateArgumentDeduction(*this, Partial, | |||
2982 | /*IsPartialOrdering=*/false, | |||
2983 | TemplateArgs, Deduced, Info); | |||
2984 | }); | |||
2985 | return Result; | |||
2986 | } | |||
2987 | ||||
2988 | /// Perform template argument deduction to determine whether | |||
2989 | /// the given template arguments match the given variable template | |||
2990 | /// partial specialization per C++ [temp.class.spec.match]. | |||
2991 | Sema::TemplateDeductionResult | |||
2992 | Sema::DeduceTemplateArguments(VarTemplatePartialSpecializationDecl *Partial, | |||
2993 | const TemplateArgumentList &TemplateArgs, | |||
2994 | TemplateDeductionInfo &Info) { | |||
2995 | if (Partial->isInvalidDecl()) | |||
2996 | return TDK_Invalid; | |||
2997 | ||||
2998 | // C++ [temp.class.spec.match]p2: | |||
2999 | // A partial specialization matches a given actual template | |||
3000 | // argument list if the template arguments of the partial | |||
3001 | // specialization can be deduced from the actual template argument | |||
3002 | // list (14.8.2). | |||
3003 | ||||
3004 | // Unevaluated SFINAE context. | |||
3005 | EnterExpressionEvaluationContext Unevaluated( | |||
3006 | *this, Sema::ExpressionEvaluationContext::Unevaluated); | |||
3007 | SFINAETrap Trap(*this); | |||
3008 | ||||
3009 | // This deduction has no relation to any outer instantiation we might be | |||
3010 | // performing. | |||
3011 | LocalInstantiationScope InstantiationScope(*this); | |||
3012 | ||||
3013 | SmallVector<DeducedTemplateArgument, 4> Deduced; | |||
3014 | Deduced.resize(Partial->getTemplateParameters()->size()); | |||
3015 | if (TemplateDeductionResult Result = ::DeduceTemplateArguments( | |||
3016 | *this, Partial->getTemplateParameters(), Partial->getTemplateArgs(), | |||
3017 | TemplateArgs, Info, Deduced)) | |||
3018 | return Result; | |||
3019 | ||||
3020 | SmallVector<TemplateArgument, 4> DeducedArgs(Deduced.begin(), Deduced.end()); | |||
3021 | InstantiatingTemplate Inst(*this, Info.getLocation(), Partial, DeducedArgs, | |||
3022 | Info); | |||
3023 | if (Inst.isInvalid()) | |||
3024 | return TDK_InstantiationDepth; | |||
3025 | ||||
3026 | if (Trap.hasErrorOccurred()) | |||
3027 | return Sema::TDK_SubstitutionFailure; | |||
3028 | ||||
3029 | TemplateDeductionResult Result; | |||
3030 | runWithSufficientStackSpace(Info.getLocation(), [&] { | |||
3031 | Result = ::FinishTemplateArgumentDeduction(*this, Partial, | |||
3032 | /*IsPartialOrdering=*/false, | |||
3033 | TemplateArgs, Deduced, Info); | |||
3034 | }); | |||
3035 | return Result; | |||
3036 | } | |||
3037 | ||||
3038 | /// Determine whether the given type T is a simple-template-id type. | |||
3039 | static bool isSimpleTemplateIdType(QualType T) { | |||
3040 | if (const TemplateSpecializationType *Spec | |||
3041 | = T->getAs<TemplateSpecializationType>()) | |||
3042 | return Spec->getTemplateName().getAsTemplateDecl() != nullptr; | |||
3043 | ||||
3044 | // C++17 [temp.local]p2: | |||
3045 | // the injected-class-name [...] is equivalent to the template-name followed | |||
3046 | // by the template-arguments of the class template specialization or partial | |||
3047 | // specialization enclosed in <> | |||
3048 | // ... which means it's equivalent to a simple-template-id. | |||
3049 | // | |||
3050 | // This only arises during class template argument deduction for a copy | |||
3051 | // deduction candidate, where it permits slicing. | |||
3052 | if (T->getAs<InjectedClassNameType>()) | |||
3053 | return true; | |||
3054 | ||||
3055 | return false; | |||
3056 | } | |||
3057 | ||||
3058 | /// Substitute the explicitly-provided template arguments into the | |||
3059 | /// given function template according to C++ [temp.arg.explicit]. | |||
3060 | /// | |||
3061 | /// \param FunctionTemplate the function template into which the explicit | |||
3062 | /// template arguments will be substituted. | |||
3063 | /// | |||
3064 | /// \param ExplicitTemplateArgs the explicitly-specified template | |||
3065 | /// arguments. | |||
3066 | /// | |||
3067 | /// \param Deduced the deduced template arguments, which will be populated | |||
3068 | /// with the converted and checked explicit template arguments. | |||
3069 | /// | |||
3070 | /// \param ParamTypes will be populated with the instantiated function | |||
3071 | /// parameters. | |||
3072 | /// | |||
3073 | /// \param FunctionType if non-NULL, the result type of the function template | |||
3074 | /// will also be instantiated and the pointed-to value will be updated with | |||
3075 | /// the instantiated function type. | |||
3076 | /// | |||
3077 | /// \param Info if substitution fails for any reason, this object will be | |||
3078 | /// populated with more information about the failure. | |||
3079 | /// | |||
3080 | /// \returns TDK_Success if substitution was successful, or some failure | |||
3081 | /// condition. | |||
3082 | Sema::TemplateDeductionResult | |||
3083 | Sema::SubstituteExplicitTemplateArguments( | |||
3084 | FunctionTemplateDecl *FunctionTemplate, | |||
3085 | TemplateArgumentListInfo &ExplicitTemplateArgs, | |||
3086 | SmallVectorImpl<DeducedTemplateArgument> &Deduced, | |||
3087 | SmallVectorImpl<QualType> &ParamTypes, | |||
3088 | QualType *FunctionType, | |||
3089 | TemplateDeductionInfo &Info) { | |||
3090 | FunctionDecl *Function = FunctionTemplate->getTemplatedDecl(); | |||
3091 | TemplateParameterList *TemplateParams | |||
3092 | = FunctionTemplate->getTemplateParameters(); | |||
3093 | ||||
3094 | if (ExplicitTemplateArgs.size() == 0) { | |||
3095 | // No arguments to substitute; just copy over the parameter types and | |||
3096 | // fill in the function type. | |||
3097 | for (auto P : Function->parameters()) | |||
3098 | ParamTypes.push_back(P->getType()); | |||
3099 | ||||
3100 | if (FunctionType) | |||
3101 | *FunctionType = Function->getType(); | |||
3102 | return TDK_Success; | |||
3103 | } | |||
3104 | ||||
3105 | // Unevaluated SFINAE context. | |||
3106 | EnterExpressionEvaluationContext Unevaluated( | |||
3107 | *this, Sema::ExpressionEvaluationContext::Unevaluated); | |||
3108 | SFINAETrap Trap(*this); | |||
3109 | ||||
3110 | // C++ [temp.arg.explicit]p3: | |||
3111 | // Template arguments that are present shall be specified in the | |||
3112 | // declaration order of their corresponding template-parameters. The | |||
3113 | // template argument list shall not specify more template-arguments than | |||
3114 | // there are corresponding template-parameters. | |||
3115 | SmallVector<TemplateArgument, 4> Builder; | |||
3116 | ||||
3117 | // Enter a new template instantiation context where we check the | |||
3118 | // explicitly-specified template arguments against this function template, | |||
3119 | // and then substitute them into the function parameter types. | |||
3120 | SmallVector<TemplateArgument, 4> DeducedArgs; | |||
3121 | InstantiatingTemplate Inst( | |||
3122 | *this, Info.getLocation(), FunctionTemplate, DeducedArgs, | |||
3123 | CodeSynthesisContext::ExplicitTemplateArgumentSubstitution, Info); | |||
3124 | if (Inst.isInvalid()) | |||
3125 | return TDK_InstantiationDepth; | |||
3126 | ||||
3127 | if (CheckTemplateArgumentList(FunctionTemplate, SourceLocation(), | |||
3128 | ExplicitTemplateArgs, true, Builder, false) || | |||
3129 | Trap.hasErrorOccurred()) { | |||
3130 | unsigned Index = Builder.size(); | |||
3131 | if (Index >= TemplateParams->size()) | |||
3132 | return TDK_SubstitutionFailure; | |||
3133 | Info.Param = makeTemplateParameter(TemplateParams->getParam(Index)); | |||
3134 | return TDK_InvalidExplicitArguments; | |||
3135 | } | |||
3136 | ||||
3137 | // Form the template argument list from the explicitly-specified | |||
3138 | // template arguments. | |||
3139 | TemplateArgumentList *ExplicitArgumentList | |||
3140 | = TemplateArgumentList::CreateCopy(Context, Builder); | |||
3141 | Info.setExplicitArgs(ExplicitArgumentList); | |||
3142 | ||||
3143 | // Template argument deduction and the final substitution should be | |||
3144 | // done in the context of the templated declaration. Explicit | |||
3145 | // argument substitution, on the other hand, needs to happen in the | |||
3146 | // calling context. | |||
3147 | ContextRAII SavedContext(*this, FunctionTemplate->getTemplatedDecl()); | |||
3148 | ||||
3149 | // If we deduced template arguments for a template parameter pack, | |||
3150 | // note that the template argument pack is partially substituted and record | |||
3151 | // the explicit template arguments. They'll be used as part of deduction | |||
3152 | // for this template parameter pack. | |||
3153 | unsigned PartiallySubstitutedPackIndex = -1u; | |||
3154 | if (!Builder.empty()) { | |||
3155 | const TemplateArgument &Arg = Builder.back(); | |||
3156 | if (Arg.getKind() == TemplateArgument::Pack) { | |||
3157 | auto *Param = TemplateParams->getParam(Builder.size() - 1); | |||
3158 | // If this is a fully-saturated fixed-size pack, it should be | |||
3159 | // fully-substituted, not partially-substituted. | |||
3160 | Optional<unsigned> Expansions = getExpandedPackSize(Param); | |||
3161 | if (!Expansions || Arg.pack_size() < *Expansions) { | |||
3162 | PartiallySubstitutedPackIndex = Builder.size() - 1; | |||
3163 | CurrentInstantiationScope->SetPartiallySubstitutedPack( | |||
3164 | Param, Arg.pack_begin(), Arg.pack_size()); | |||
3165 | } | |||
3166 | } | |||
3167 | } | |||
3168 | ||||
3169 | const FunctionProtoType *Proto | |||
3170 | = Function->getType()->getAs<FunctionProtoType>(); | |||
3171 | assert(Proto && "Function template does not have a prototype?")(static_cast <bool> (Proto && "Function template does not have a prototype?" ) ? void (0) : __assert_fail ("Proto && \"Function template does not have a prototype?\"" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 3171, __extension__ __PRETTY_FUNCTION__)); | |||
3172 | ||||
3173 | // Isolate our substituted parameters from our caller. | |||
3174 | LocalInstantiationScope InstScope(*this, /*MergeWithOuterScope*/true); | |||
3175 | ||||
3176 | ExtParameterInfoBuilder ExtParamInfos; | |||
3177 | ||||
3178 | // Instantiate the types of each of the function parameters given the | |||
3179 | // explicitly-specified template arguments. If the function has a trailing | |||
3180 | // return type, substitute it after the arguments to ensure we substitute | |||
3181 | // in lexical order. | |||
3182 | if (Proto->hasTrailingReturn()) { | |||
3183 | if (SubstParmTypes(Function->getLocation(), Function->parameters(), | |||
3184 | Proto->getExtParameterInfosOrNull(), | |||
3185 | MultiLevelTemplateArgumentList(*ExplicitArgumentList), | |||
3186 | ParamTypes, /*params*/ nullptr, ExtParamInfos)) | |||
3187 | return TDK_SubstitutionFailure; | |||
3188 | } | |||
3189 | ||||
3190 | // Instantiate the return type. | |||
3191 | QualType ResultType; | |||
3192 | { | |||
3193 | // C++11 [expr.prim.general]p3: | |||
3194 | // If a declaration declares a member function or member function | |||
3195 | // template of a class X, the expression this is a prvalue of type | |||
3196 | // "pointer to cv-qualifier-seq X" between the optional cv-qualifer-seq | |||
3197 | // and the end of the function-definition, member-declarator, or | |||
3198 | // declarator. | |||
3199 | Qualifiers ThisTypeQuals; | |||
3200 | CXXRecordDecl *ThisContext = nullptr; | |||
3201 | if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Function)) { | |||
3202 | ThisContext = Method->getParent(); | |||
3203 | ThisTypeQuals = Method->getMethodQualifiers(); | |||
3204 | } | |||
3205 | ||||
3206 | CXXThisScopeRAII ThisScope(*this, ThisContext, ThisTypeQuals, | |||
3207 | getLangOpts().CPlusPlus11); | |||
3208 | ||||
3209 | ResultType = | |||
3210 | SubstType(Proto->getReturnType(), | |||
3211 | MultiLevelTemplateArgumentList(*ExplicitArgumentList), | |||
3212 | Function->getTypeSpecStartLoc(), Function->getDeclName()); | |||
3213 | if (ResultType.isNull() || Trap.hasErrorOccurred()) | |||
3214 | return TDK_SubstitutionFailure; | |||
3215 | // CUDA: Kernel function must have 'void' return type. | |||
3216 | if (getLangOpts().CUDA) | |||
3217 | if (Function->hasAttr<CUDAGlobalAttr>() && !ResultType->isVoidType()) { | |||
3218 | Diag(Function->getLocation(), diag::err_kern_type_not_void_return) | |||
3219 | << Function->getType() << Function->getSourceRange(); | |||
3220 | return TDK_SubstitutionFailure; | |||
3221 | } | |||
3222 | } | |||
3223 | ||||
3224 | // Instantiate the types of each of the function parameters given the | |||
3225 | // explicitly-specified template arguments if we didn't do so earlier. | |||
3226 | if (!Proto->hasTrailingReturn() && | |||
3227 | SubstParmTypes(Function->getLocation(), Function->parameters(), | |||
3228 | Proto->getExtParameterInfosOrNull(), | |||
3229 | MultiLevelTemplateArgumentList(*ExplicitArgumentList), | |||
3230 | ParamTypes, /*params*/ nullptr, ExtParamInfos)) | |||
3231 | return TDK_SubstitutionFailure; | |||
3232 | ||||
3233 | if (FunctionType) { | |||
3234 | auto EPI = Proto->getExtProtoInfo(); | |||
3235 | EPI.ExtParameterInfos = ExtParamInfos.getPointerOrNull(ParamTypes.size()); | |||
3236 | ||||
3237 | // In C++1z onwards, exception specifications are part of the function type, | |||
3238 | // so substitution into the type must also substitute into the exception | |||
3239 | // specification. | |||
3240 | SmallVector<QualType, 4> ExceptionStorage; | |||
3241 | if (getLangOpts().CPlusPlus17 && | |||
3242 | SubstExceptionSpec( | |||
3243 | Function->getLocation(), EPI.ExceptionSpec, ExceptionStorage, | |||
3244 | MultiLevelTemplateArgumentList(*ExplicitArgumentList))) | |||
3245 | return TDK_SubstitutionFailure; | |||
3246 | ||||
3247 | *FunctionType = BuildFunctionType(ResultType, ParamTypes, | |||
3248 | Function->getLocation(), | |||
3249 | Function->getDeclName(), | |||
3250 | EPI); | |||
3251 | if (FunctionType->isNull() || Trap.hasErrorOccurred()) | |||
3252 | return TDK_SubstitutionFailure; | |||
3253 | } | |||
3254 | ||||
3255 | // C++ [temp.arg.explicit]p2: | |||
3256 | // Trailing template arguments that can be deduced (14.8.2) may be | |||
3257 | // omitted from the list of explicit template-arguments. If all of the | |||
3258 | // template arguments can be deduced, they may all be omitted; in this | |||
3259 | // case, the empty template argument list <> itself may also be omitted. | |||
3260 | // | |||
3261 | // Take all of the explicitly-specified arguments and put them into | |||
3262 | // the set of deduced template arguments. The partially-substituted | |||
3263 | // parameter pack, however, will be set to NULL since the deduction | |||
3264 | // mechanism handles the partially-substituted argument pack directly. | |||
3265 | Deduced.reserve(TemplateParams->size()); | |||
3266 | for (unsigned I = 0, N = ExplicitArgumentList->size(); I != N; ++I) { | |||
3267 | const TemplateArgument &Arg = ExplicitArgumentList->get(I); | |||
3268 | if (I == PartiallySubstitutedPackIndex) | |||
3269 | Deduced.push_back(DeducedTemplateArgument()); | |||
3270 | else | |||
3271 | Deduced.push_back(Arg); | |||
3272 | } | |||
3273 | ||||
3274 | return TDK_Success; | |||
3275 | } | |||
3276 | ||||
3277 | /// Check whether the deduced argument type for a call to a function | |||
3278 | /// template matches the actual argument type per C++ [temp.deduct.call]p4. | |||
3279 | static Sema::TemplateDeductionResult | |||
3280 | CheckOriginalCallArgDeduction(Sema &S, TemplateDeductionInfo &Info, | |||
3281 | Sema::OriginalCallArg OriginalArg, | |||
3282 | QualType DeducedA) { | |||
3283 | ASTContext &Context = S.Context; | |||
3284 | ||||
3285 | auto Failed = [&]() -> Sema::TemplateDeductionResult { | |||
3286 | Info.FirstArg = TemplateArgument(DeducedA); | |||
3287 | Info.SecondArg = TemplateArgument(OriginalArg.OriginalArgType); | |||
3288 | Info.CallArgIndex = OriginalArg.ArgIdx; | |||
3289 | return OriginalArg.DecomposedParam ? Sema::TDK_DeducedMismatchNested | |||
3290 | : Sema::TDK_DeducedMismatch; | |||
3291 | }; | |||
3292 | ||||
3293 | QualType A = OriginalArg.OriginalArgType; | |||
3294 | QualType OriginalParamType = OriginalArg.OriginalParamType; | |||
3295 | ||||
3296 | // Check for type equality (top-level cv-qualifiers are ignored). | |||
3297 | if (Context.hasSameUnqualifiedType(A, DeducedA)) | |||
3298 | return Sema::TDK_Success; | |||
3299 | ||||
3300 | // Strip off references on the argument types; they aren't needed for | |||
3301 | // the following checks. | |||
3302 | if (const ReferenceType *DeducedARef = DeducedA->getAs<ReferenceType>()) | |||
3303 | DeducedA = DeducedARef->getPointeeType(); | |||
3304 | if (const ReferenceType *ARef = A->getAs<ReferenceType>()) | |||
3305 | A = ARef->getPointeeType(); | |||
3306 | ||||
3307 | // C++ [temp.deduct.call]p4: | |||
3308 | // [...] However, there are three cases that allow a difference: | |||
3309 | // - If the original P is a reference type, the deduced A (i.e., the | |||
3310 | // type referred to by the reference) can be more cv-qualified than | |||
3311 | // the transformed A. | |||
3312 | if (const ReferenceType *OriginalParamRef | |||
3313 | = OriginalParamType->getAs<ReferenceType>()) { | |||
3314 | // We don't want to keep the reference around any more. | |||
3315 | OriginalParamType = OriginalParamRef->getPointeeType(); | |||
3316 | ||||
3317 | // FIXME: Resolve core issue (no number yet): if the original P is a | |||
3318 | // reference type and the transformed A is function type "noexcept F", | |||
3319 | // the deduced A can be F. | |||
3320 | QualType Tmp; | |||
3321 | if (A->isFunctionType() && S.IsFunctionConversion(A, DeducedA, Tmp)) | |||
3322 | return Sema::TDK_Success; | |||
3323 | ||||
3324 | Qualifiers AQuals = A.getQualifiers(); | |||
3325 | Qualifiers DeducedAQuals = DeducedA.getQualifiers(); | |||
3326 | ||||
3327 | // Under Objective-C++ ARC, the deduced type may have implicitly | |||
3328 | // been given strong or (when dealing with a const reference) | |||
3329 | // unsafe_unretained lifetime. If so, update the original | |||
3330 | // qualifiers to include this lifetime. | |||
3331 | if (S.getLangOpts().ObjCAutoRefCount && | |||
3332 | ((DeducedAQuals.getObjCLifetime() == Qualifiers::OCL_Strong && | |||
3333 | AQuals.getObjCLifetime() == Qualifiers::OCL_None) || | |||
3334 | (DeducedAQuals.hasConst() && | |||
3335 | DeducedAQuals.getObjCLifetime() == Qualifiers::OCL_ExplicitNone))) { | |||
3336 | AQuals.setObjCLifetime(DeducedAQuals.getObjCLifetime()); | |||
3337 | } | |||
3338 | ||||
3339 | if (AQuals == DeducedAQuals) { | |||
3340 | // Qualifiers match; there's nothing to do. | |||
3341 | } else if (!DeducedAQuals.compatiblyIncludes(AQuals)) { | |||
3342 | return Failed(); | |||
3343 | } else { | |||
3344 | // Qualifiers are compatible, so have the argument type adopt the | |||
3345 | // deduced argument type's qualifiers as if we had performed the | |||
3346 | // qualification conversion. | |||
3347 | A = Context.getQualifiedType(A.getUnqualifiedType(), DeducedAQuals); | |||
3348 | } | |||
3349 | } | |||
3350 | ||||
3351 | // - The transformed A can be another pointer or pointer to member | |||
3352 | // type that can be converted to the deduced A via a function pointer | |||
3353 | // conversion and/or a qualification conversion. | |||
3354 | // | |||
3355 | // Also allow conversions which merely strip __attribute__((noreturn)) from | |||
3356 | // function types (recursively). | |||
3357 | bool ObjCLifetimeConversion = false; | |||
3358 | QualType ResultTy; | |||
3359 | if ((A->isAnyPointerType() || A->isMemberPointerType()) && | |||
3360 | (S.IsQualificationConversion(A, DeducedA, false, | |||
3361 | ObjCLifetimeConversion) || | |||
3362 | S.IsFunctionConversion(A, DeducedA, ResultTy))) | |||
3363 | return Sema::TDK_Success; | |||
3364 | ||||
3365 | // - If P is a class and P has the form simple-template-id, then the | |||
3366 | // transformed A can be a derived class of the deduced A. [...] | |||
3367 | // [...] Likewise, if P is a pointer to a class of the form | |||
3368 | // simple-template-id, the transformed A can be a pointer to a | |||
3369 | // derived class pointed to by the deduced A. | |||
3370 | if (const PointerType *OriginalParamPtr | |||
3371 | = OriginalParamType->getAs<PointerType>()) { | |||
3372 | if (const PointerType *DeducedAPtr = DeducedA->getAs<PointerType>()) { | |||
3373 | if (const PointerType *APtr = A->getAs<PointerType>()) { | |||
3374 | if (A->getPointeeType()->isRecordType()) { | |||
3375 | OriginalParamType = OriginalParamPtr->getPointeeType(); | |||
3376 | DeducedA = DeducedAPtr->getPointeeType(); | |||
3377 | A = APtr->getPointeeType(); | |||
3378 | } | |||
3379 | } | |||
3380 | } | |||
3381 | } | |||
3382 | ||||
3383 | if (Context.hasSameUnqualifiedType(A, DeducedA)) | |||
3384 | return Sema::TDK_Success; | |||
3385 | ||||
3386 | if (A->isRecordType() && isSimpleTemplateIdType(OriginalParamType) && | |||
3387 | S.IsDerivedFrom(Info.getLocation(), A, DeducedA)) | |||
3388 | return Sema::TDK_Success; | |||
3389 | ||||
3390 | return Failed(); | |||
3391 | } | |||
3392 | ||||
3393 | /// Find the pack index for a particular parameter index in an instantiation of | |||
3394 | /// a function template with specific arguments. | |||
3395 | /// | |||
3396 | /// \return The pack index for whichever pack produced this parameter, or -1 | |||
3397 | /// if this was not produced by a parameter. Intended to be used as the | |||
3398 | /// ArgumentPackSubstitutionIndex for further substitutions. | |||
3399 | // FIXME: We should track this in OriginalCallArgs so we don't need to | |||
3400 | // reconstruct it here. | |||
3401 | static unsigned getPackIndexForParam(Sema &S, | |||
3402 | FunctionTemplateDecl *FunctionTemplate, | |||
3403 | const MultiLevelTemplateArgumentList &Args, | |||
3404 | unsigned ParamIdx) { | |||
3405 | unsigned Idx = 0; | |||
3406 | for (auto *PD : FunctionTemplate->getTemplatedDecl()->parameters()) { | |||
3407 | if (PD->isParameterPack()) { | |||
3408 | unsigned NumExpansions = | |||
3409 | S.getNumArgumentsInExpansion(PD->getType(), Args).getValueOr(1); | |||
3410 | if (Idx + NumExpansions > ParamIdx) | |||
3411 | return ParamIdx - Idx; | |||
3412 | Idx += NumExpansions; | |||
3413 | } else { | |||
3414 | if (Idx == ParamIdx) | |||
3415 | return -1; // Not a pack expansion | |||
3416 | ++Idx; | |||
3417 | } | |||
3418 | } | |||
3419 | ||||
3420 | llvm_unreachable("parameter index would not be produced from template")::llvm::llvm_unreachable_internal("parameter index would not be produced from template" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 3420); | |||
3421 | } | |||
3422 | ||||
3423 | /// Finish template argument deduction for a function template, | |||
3424 | /// checking the deduced template arguments for completeness and forming | |||
3425 | /// the function template specialization. | |||
3426 | /// | |||
3427 | /// \param OriginalCallArgs If non-NULL, the original call arguments against | |||
3428 | /// which the deduced argument types should be compared. | |||
3429 | Sema::TemplateDeductionResult Sema::FinishTemplateArgumentDeduction( | |||
3430 | FunctionTemplateDecl *FunctionTemplate, | |||
3431 | SmallVectorImpl<DeducedTemplateArgument> &Deduced, | |||
3432 | unsigned NumExplicitlySpecified, FunctionDecl *&Specialization, | |||
3433 | TemplateDeductionInfo &Info, | |||
3434 | SmallVectorImpl<OriginalCallArg> const *OriginalCallArgs, | |||
3435 | bool PartialOverloading, llvm::function_ref<bool()> CheckNonDependent) { | |||
3436 | // Unevaluated SFINAE context. | |||
3437 | EnterExpressionEvaluationContext Unevaluated( | |||
3438 | *this, Sema::ExpressionEvaluationContext::Unevaluated); | |||
3439 | SFINAETrap Trap(*this); | |||
3440 | ||||
3441 | // Enter a new template instantiation context while we instantiate the | |||
3442 | // actual function declaration. | |||
3443 | SmallVector<TemplateArgument, 4> DeducedArgs(Deduced.begin(), Deduced.end()); | |||
3444 | InstantiatingTemplate Inst( | |||
3445 | *this, Info.getLocation(), FunctionTemplate, DeducedArgs, | |||
3446 | CodeSynthesisContext::DeducedTemplateArgumentSubstitution, Info); | |||
3447 | if (Inst.isInvalid()) | |||
3448 | return TDK_InstantiationDepth; | |||
3449 | ||||
3450 | ContextRAII SavedContext(*this, FunctionTemplate->getTemplatedDecl()); | |||
3451 | ||||
3452 | // C++ [temp.deduct.type]p2: | |||
3453 | // [...] or if any template argument remains neither deduced nor | |||
3454 | // explicitly specified, template argument deduction fails. | |||
3455 | SmallVector<TemplateArgument, 4> Builder; | |||
3456 | if (auto Result = ConvertDeducedTemplateArguments( | |||
3457 | *this, FunctionTemplate, /*IsDeduced*/true, Deduced, Info, Builder, | |||
3458 | CurrentInstantiationScope, NumExplicitlySpecified, | |||
3459 | PartialOverloading)) | |||
3460 | return Result; | |||
3461 | ||||
3462 | // C++ [temp.deduct.call]p10: [DR1391] | |||
3463 | // If deduction succeeds for all parameters that contain | |||
3464 | // template-parameters that participate in template argument deduction, | |||
3465 | // and all template arguments are explicitly specified, deduced, or | |||
3466 | // obtained from default template arguments, remaining parameters are then | |||
3467 | // compared with the corresponding arguments. For each remaining parameter | |||
3468 | // P with a type that was non-dependent before substitution of any | |||
3469 | // explicitly-specified template arguments, if the corresponding argument | |||
3470 | // A cannot be implicitly converted to P, deduction fails. | |||
3471 | if (CheckNonDependent()) | |||
3472 | return TDK_NonDependentConversionFailure; | |||
3473 | ||||
3474 | // Form the template argument list from the deduced template arguments. | |||
3475 | TemplateArgumentList *DeducedArgumentList | |||
3476 | = TemplateArgumentList::CreateCopy(Context, Builder); | |||
3477 | Info.reset(DeducedArgumentList); | |||
3478 | ||||
3479 | // Substitute the deduced template arguments into the function template | |||
3480 | // declaration to produce the function template specialization. | |||
3481 | DeclContext *Owner = FunctionTemplate->getDeclContext(); | |||
3482 | if (FunctionTemplate->getFriendObjectKind()) | |||
3483 | Owner = FunctionTemplate->getLexicalDeclContext(); | |||
3484 | MultiLevelTemplateArgumentList SubstArgs(*DeducedArgumentList); | |||
3485 | Specialization = cast_or_null<FunctionDecl>( | |||
3486 | SubstDecl(FunctionTemplate->getTemplatedDecl(), Owner, SubstArgs)); | |||
3487 | if (!Specialization || Specialization->isInvalidDecl()) | |||
3488 | return TDK_SubstitutionFailure; | |||
3489 | ||||
3490 | assert(Specialization->getPrimaryTemplate()->getCanonicalDecl() ==(static_cast <bool> (Specialization->getPrimaryTemplate ()->getCanonicalDecl() == FunctionTemplate->getCanonicalDecl ()) ? void (0) : __assert_fail ("Specialization->getPrimaryTemplate()->getCanonicalDecl() == FunctionTemplate->getCanonicalDecl()" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 3491, __extension__ __PRETTY_FUNCTION__)) | |||
3491 | FunctionTemplate->getCanonicalDecl())(static_cast <bool> (Specialization->getPrimaryTemplate ()->getCanonicalDecl() == FunctionTemplate->getCanonicalDecl ()) ? void (0) : __assert_fail ("Specialization->getPrimaryTemplate()->getCanonicalDecl() == FunctionTemplate->getCanonicalDecl()" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 3491, __extension__ __PRETTY_FUNCTION__)); | |||
3492 | ||||
3493 | // If the template argument list is owned by the function template | |||
3494 | // specialization, release it. | |||
3495 | if (Specialization->getTemplateSpecializationArgs() == DeducedArgumentList && | |||
3496 | !Trap.hasErrorOccurred()) | |||
3497 | Info.take(); | |||
3498 | ||||
3499 | // There may have been an error that did not prevent us from constructing a | |||
3500 | // declaration. Mark the declaration invalid and return with a substitution | |||
3501 | // failure. | |||
3502 | if (Trap.hasErrorOccurred()) { | |||
3503 | Specialization->setInvalidDecl(true); | |||
3504 | return TDK_SubstitutionFailure; | |||
3505 | } | |||
3506 | ||||
3507 | // C++2a [temp.deduct]p5 | |||
3508 | // [...] When all template arguments have been deduced [...] all uses of | |||
3509 | // template parameters [...] are replaced with the corresponding deduced | |||
3510 | // or default argument values. | |||
3511 | // [...] If the function template has associated constraints | |||
3512 | // ([temp.constr.decl]), those constraints are checked for satisfaction | |||
3513 | // ([temp.constr.constr]). If the constraints are not satisfied, type | |||
3514 | // deduction fails. | |||
3515 | if (!PartialOverloading || | |||
3516 | (Builder.size() == FunctionTemplate->getTemplateParameters()->size())) { | |||
3517 | if (CheckInstantiatedFunctionTemplateConstraints(Info.getLocation(), | |||
3518 | Specialization, Builder, Info.AssociatedConstraintsSatisfaction)) | |||
3519 | return TDK_MiscellaneousDeductionFailure; | |||
3520 | ||||
3521 | if (!Info.AssociatedConstraintsSatisfaction.IsSatisfied) { | |||
3522 | Info.reset(TemplateArgumentList::CreateCopy(Context, Builder)); | |||
3523 | return TDK_ConstraintsNotSatisfied; | |||
3524 | } | |||
3525 | } | |||
3526 | ||||
3527 | if (OriginalCallArgs) { | |||
3528 | // C++ [temp.deduct.call]p4: | |||
3529 | // In general, the deduction process attempts to find template argument | |||
3530 | // values that will make the deduced A identical to A (after the type A | |||
3531 | // is transformed as described above). [...] | |||
3532 | llvm::SmallDenseMap<std::pair<unsigned, QualType>, QualType> DeducedATypes; | |||
3533 | for (unsigned I = 0, N = OriginalCallArgs->size(); I != N; ++I) { | |||
3534 | OriginalCallArg OriginalArg = (*OriginalCallArgs)[I]; | |||
3535 | ||||
3536 | auto ParamIdx = OriginalArg.ArgIdx; | |||
3537 | if (ParamIdx >= Specialization->getNumParams()) | |||
3538 | // FIXME: This presumably means a pack ended up smaller than we | |||
3539 | // expected while deducing. Should this not result in deduction | |||
3540 | // failure? Can it even happen? | |||
3541 | continue; | |||
3542 | ||||
3543 | QualType DeducedA; | |||
3544 | if (!OriginalArg.DecomposedParam) { | |||
3545 | // P is one of the function parameters, just look up its substituted | |||
3546 | // type. | |||
3547 | DeducedA = Specialization->getParamDecl(ParamIdx)->getType(); | |||
3548 | } else { | |||
3549 | // P is a decomposed element of a parameter corresponding to a | |||
3550 | // braced-init-list argument. Substitute back into P to find the | |||
3551 | // deduced A. | |||
3552 | QualType &CacheEntry = | |||
3553 | DeducedATypes[{ParamIdx, OriginalArg.OriginalParamType}]; | |||
3554 | if (CacheEntry.isNull()) { | |||
3555 | ArgumentPackSubstitutionIndexRAII PackIndex( | |||
3556 | *this, getPackIndexForParam(*this, FunctionTemplate, SubstArgs, | |||
3557 | ParamIdx)); | |||
3558 | CacheEntry = | |||
3559 | SubstType(OriginalArg.OriginalParamType, SubstArgs, | |||
3560 | Specialization->getTypeSpecStartLoc(), | |||
3561 | Specialization->getDeclName()); | |||
3562 | } | |||
3563 | DeducedA = CacheEntry; | |||
3564 | } | |||
3565 | ||||
3566 | if (auto TDK = | |||
3567 | CheckOriginalCallArgDeduction(*this, Info, OriginalArg, DeducedA)) | |||
3568 | return TDK; | |||
3569 | } | |||
3570 | } | |||
3571 | ||||
3572 | // If we suppressed any diagnostics while performing template argument | |||
3573 | // deduction, and if we haven't already instantiated this declaration, | |||
3574 | // keep track of these diagnostics. They'll be emitted if this specialization | |||
3575 | // is actually used. | |||
3576 | if (Info.diag_begin() != Info.diag_end()) { | |||
3577 | SuppressedDiagnosticsMap::iterator | |||
3578 | Pos = SuppressedDiagnostics.find(Specialization->getCanonicalDecl()); | |||
3579 | if (Pos == SuppressedDiagnostics.end()) | |||
3580 | SuppressedDiagnostics[Specialization->getCanonicalDecl()] | |||
3581 | .append(Info.diag_begin(), Info.diag_end()); | |||
3582 | } | |||
3583 | ||||
3584 | return TDK_Success; | |||
3585 | } | |||
3586 | ||||
3587 | /// Gets the type of a function for template-argument-deducton | |||
3588 | /// purposes when it's considered as part of an overload set. | |||
3589 | static QualType GetTypeOfFunction(Sema &S, const OverloadExpr::FindResult &R, | |||
3590 | FunctionDecl *Fn) { | |||
3591 | // We may need to deduce the return type of the function now. | |||
3592 | if (S.getLangOpts().CPlusPlus14 && Fn->getReturnType()->isUndeducedType() && | |||
3593 | S.DeduceReturnType(Fn, R.Expression->getExprLoc(), /*Diagnose*/ false)) | |||
3594 | return {}; | |||
3595 | ||||
3596 | if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Fn)) | |||
3597 | if (Method->isInstance()) { | |||
3598 | // An instance method that's referenced in a form that doesn't | |||
3599 | // look like a member pointer is just invalid. | |||
3600 | if (!R.HasFormOfMemberPointer) | |||
3601 | return {}; | |||
3602 | ||||
3603 | return S.Context.getMemberPointerType(Fn->getType(), | |||
3604 | S.Context.getTypeDeclType(Method->getParent()).getTypePtr()); | |||
3605 | } | |||
3606 | ||||
3607 | if (!R.IsAddressOfOperand) return Fn->getType(); | |||
3608 | return S.Context.getPointerType(Fn->getType()); | |||
3609 | } | |||
3610 | ||||
3611 | /// Apply the deduction rules for overload sets. | |||
3612 | /// | |||
3613 | /// \return the null type if this argument should be treated as an | |||
3614 | /// undeduced context | |||
3615 | static QualType | |||
3616 | ResolveOverloadForDeduction(Sema &S, TemplateParameterList *TemplateParams, | |||
3617 | Expr *Arg, QualType ParamType, | |||
3618 | bool ParamWasReference) { | |||
3619 | ||||
3620 | OverloadExpr::FindResult R = OverloadExpr::find(Arg); | |||
3621 | ||||
3622 | OverloadExpr *Ovl = R.Expression; | |||
3623 | ||||
3624 | // C++0x [temp.deduct.call]p4 | |||
3625 | unsigned TDF = 0; | |||
3626 | if (ParamWasReference) | |||
3627 | TDF |= TDF_ParamWithReferenceType; | |||
3628 | if (R.IsAddressOfOperand) | |||
3629 | TDF |= TDF_IgnoreQualifiers; | |||
3630 | ||||
3631 | // C++0x [temp.deduct.call]p6: | |||
3632 | // When P is a function type, pointer to function type, or pointer | |||
3633 | // to member function type: | |||
3634 | ||||
3635 | if (!ParamType->isFunctionType() && | |||
3636 | !ParamType->isFunctionPointerType() && | |||
3637 | !ParamType->isMemberFunctionPointerType()) { | |||
3638 | if (Ovl->hasExplicitTemplateArgs()) { | |||
3639 | // But we can still look for an explicit specialization. | |||
3640 | if (FunctionDecl *ExplicitSpec | |||
3641 | = S.ResolveSingleFunctionTemplateSpecialization(Ovl)) | |||
3642 | return GetTypeOfFunction(S, R, ExplicitSpec); | |||
3643 | } | |||
3644 | ||||
3645 | DeclAccessPair DAP; | |||
3646 | if (FunctionDecl *Viable = | |||
3647 | S.resolveAddressOfSingleOverloadCandidate(Arg, DAP)) | |||
3648 | return GetTypeOfFunction(S, R, Viable); | |||
3649 | ||||
3650 | return {}; | |||
3651 | } | |||
3652 | ||||
3653 | // Gather the explicit template arguments, if any. | |||
3654 | TemplateArgumentListInfo ExplicitTemplateArgs; | |||
3655 | if (Ovl->hasExplicitTemplateArgs()) | |||
3656 | Ovl->copyTemplateArgumentsInto(ExplicitTemplateArgs); | |||
3657 | QualType Match; | |||
3658 | for (UnresolvedSetIterator I = Ovl->decls_begin(), | |||
3659 | E = Ovl->decls_end(); I != E; ++I) { | |||
3660 | NamedDecl *D = (*I)->getUnderlyingDecl(); | |||
3661 | ||||
3662 | if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(D)) { | |||
3663 | // - If the argument is an overload set containing one or more | |||
3664 | // function templates, the parameter is treated as a | |||
3665 | // non-deduced context. | |||
3666 | if (!Ovl->hasExplicitTemplateArgs()) | |||
3667 | return {}; | |||
3668 | ||||
3669 | // Otherwise, see if we can resolve a function type | |||
3670 | FunctionDecl *Specialization = nullptr; | |||
3671 | TemplateDeductionInfo Info(Ovl->getNameLoc()); | |||
3672 | if (S.DeduceTemplateArguments(FunTmpl, &ExplicitTemplateArgs, | |||
3673 | Specialization, Info)) | |||
3674 | continue; | |||
3675 | ||||
3676 | D = Specialization; | |||
3677 | } | |||
3678 | ||||
3679 | FunctionDecl *Fn = cast<FunctionDecl>(D); | |||
3680 | QualType ArgType = GetTypeOfFunction(S, R, Fn); | |||
3681 | if (ArgType.isNull()) continue; | |||
3682 | ||||
3683 | // Function-to-pointer conversion. | |||
3684 | if (!ParamWasReference && ParamType->isPointerType() && | |||
3685 | ArgType->isFunctionType()) | |||
3686 | ArgType = S.Context.getPointerType(ArgType); | |||
3687 | ||||
3688 | // - If the argument is an overload set (not containing function | |||
3689 | // templates), trial argument deduction is attempted using each | |||
3690 | // of the members of the set. If deduction succeeds for only one | |||
3691 | // of the overload set members, that member is used as the | |||
3692 | // argument value for the deduction. If deduction succeeds for | |||
3693 | // more than one member of the overload set the parameter is | |||
3694 | // treated as a non-deduced context. | |||
3695 | ||||
3696 | // We do all of this in a fresh context per C++0x [temp.deduct.type]p2: | |||
3697 | // Type deduction is done independently for each P/A pair, and | |||
3698 | // the deduced template argument values are then combined. | |||
3699 | // So we do not reject deductions which were made elsewhere. | |||
3700 | SmallVector<DeducedTemplateArgument, 8> | |||
3701 | Deduced(TemplateParams->size()); | |||
3702 | TemplateDeductionInfo Info(Ovl->getNameLoc()); | |||
3703 | Sema::TemplateDeductionResult Result | |||
3704 | = DeduceTemplateArgumentsByTypeMatch(S, TemplateParams, ParamType, | |||
3705 | ArgType, Info, Deduced, TDF); | |||
3706 | if (Result) continue; | |||
3707 | if (!Match.isNull()) | |||
3708 | return {}; | |||
3709 | Match = ArgType; | |||
3710 | } | |||
3711 | ||||
3712 | return Match; | |||
3713 | } | |||
3714 | ||||
3715 | /// Perform the adjustments to the parameter and argument types | |||
3716 | /// described in C++ [temp.deduct.call]. | |||
3717 | /// | |||
3718 | /// \returns true if the caller should not attempt to perform any template | |||
3719 | /// argument deduction based on this P/A pair because the argument is an | |||
3720 | /// overloaded function set that could not be resolved. | |||
3721 | static bool AdjustFunctionParmAndArgTypesForDeduction( | |||
3722 | Sema &S, TemplateParameterList *TemplateParams, unsigned FirstInnerIndex, | |||
3723 | QualType &ParamType, QualType &ArgType, Expr *Arg, unsigned &TDF) { | |||
3724 | // C++0x [temp.deduct.call]p3: | |||
3725 | // If P is a cv-qualified type, the top level cv-qualifiers of P's type | |||
3726 | // are ignored for type deduction. | |||
3727 | if (ParamType.hasQualifiers()) | |||
3728 | ParamType = ParamType.getUnqualifiedType(); | |||
3729 | ||||
3730 | // [...] If P is a reference type, the type referred to by P is | |||
3731 | // used for type deduction. | |||
3732 | const ReferenceType *ParamRefType = ParamType->getAs<ReferenceType>(); | |||
3733 | if (ParamRefType) | |||
3734 | ParamType = ParamRefType->getPointeeType(); | |||
3735 | ||||
3736 | // Overload sets usually make this parameter an undeduced context, | |||
3737 | // but there are sometimes special circumstances. Typically | |||
3738 | // involving a template-id-expr. | |||
3739 | if (ArgType == S.Context.OverloadTy) { | |||
3740 | ArgType = ResolveOverloadForDeduction(S, TemplateParams, | |||
3741 | Arg, ParamType, | |||
3742 | ParamRefType != nullptr); | |||
3743 | if (ArgType.isNull()) | |||
3744 | return true; | |||
3745 | } | |||
3746 | ||||
3747 | if (ParamRefType) { | |||
3748 | // If the argument has incomplete array type, try to complete its type. | |||
3749 | if (ArgType->isIncompleteArrayType()) | |||
3750 | ArgType = S.getCompletedType(Arg); | |||
3751 | ||||
3752 | // C++1z [temp.deduct.call]p3: | |||
3753 | // If P is a forwarding reference and the argument is an lvalue, the type | |||
3754 | // "lvalue reference to A" is used in place of A for type deduction. | |||
3755 | if (isForwardingReference(QualType(ParamRefType, 0), FirstInnerIndex) && | |||
3756 | Arg->isLValue()) { | |||
3757 | if (S.getLangOpts().OpenCL && !ArgType.hasAddressSpace()) | |||
3758 | ArgType = S.Context.getAddrSpaceQualType( | |||
3759 | ArgType, S.Context.getDefaultOpenCLPointeeAddrSpace()); | |||
3760 | ArgType = S.Context.getLValueReferenceType(ArgType); | |||
3761 | } | |||
3762 | } else { | |||
3763 | // C++ [temp.deduct.call]p2: | |||
3764 | // If P is not a reference type: | |||
3765 | // - If A is an array type, the pointer type produced by the | |||
3766 | // array-to-pointer standard conversion (4.2) is used in place of | |||
3767 | // A for type deduction; otherwise, | |||
3768 | if (ArgType->isArrayType()) | |||
3769 | ArgType = S.Context.getArrayDecayedType(ArgType); | |||
3770 | // - If A is a function type, the pointer type produced by the | |||
3771 | // function-to-pointer standard conversion (4.3) is used in place | |||
3772 | // of A for type deduction; otherwise, | |||
3773 | else if (ArgType->isFunctionType()) | |||
3774 | ArgType = S.Context.getPointerType(ArgType); | |||
3775 | else { | |||
3776 | // - If A is a cv-qualified type, the top level cv-qualifiers of A's | |||
3777 | // type are ignored for type deduction. | |||
3778 | ArgType = ArgType.getUnqualifiedType(); | |||
3779 | } | |||
3780 | } | |||
3781 | ||||
3782 | // C++0x [temp.deduct.call]p4: | |||
3783 | // In general, the deduction process attempts to find template argument | |||
3784 | // values that will make the deduced A identical to A (after the type A | |||
3785 | // is transformed as described above). [...] | |||
3786 | TDF = TDF_SkipNonDependent; | |||
3787 | ||||
3788 | // - If the original P is a reference type, the deduced A (i.e., the | |||
3789 | // type referred to by the reference) can be more cv-qualified than | |||
3790 | // the transformed A. | |||
3791 | if (ParamRefType) | |||
3792 | TDF |= TDF_ParamWithReferenceType; | |||
3793 | // - The transformed A can be another pointer or pointer to member | |||
3794 | // type that can be converted to the deduced A via a qualification | |||
3795 | // conversion (4.4). | |||
3796 | if (ArgType->isPointerType() || ArgType->isMemberPointerType() || | |||
3797 | ArgType->isObjCObjectPointerType()) | |||
3798 | TDF |= TDF_IgnoreQualifiers; | |||
3799 | // - If P is a class and P has the form simple-template-id, then the | |||
3800 | // transformed A can be a derived class of the deduced A. Likewise, | |||
3801 | // if P is a pointer to a class of the form simple-template-id, the | |||
3802 | // transformed A can be a pointer to a derived class pointed to by | |||
3803 | // the deduced A. | |||
3804 | if (isSimpleTemplateIdType(ParamType) || | |||
3805 | (isa<PointerType>(ParamType) && | |||
3806 | isSimpleTemplateIdType( | |||
3807 | ParamType->castAs<PointerType>()->getPointeeType()))) | |||
3808 | TDF |= TDF_DerivedClass; | |||
3809 | ||||
3810 | return false; | |||
3811 | } | |||
3812 | ||||
3813 | static bool | |||
3814 | hasDeducibleTemplateParameters(Sema &S, FunctionTemplateDecl *FunctionTemplate, | |||
3815 | QualType T); | |||
3816 | ||||
3817 | static Sema::TemplateDeductionResult DeduceTemplateArgumentsFromCallArgument( | |||
3818 | Sema &S, TemplateParameterList *TemplateParams, unsigned FirstInnerIndex, | |||
3819 | QualType ParamType, Expr *Arg, TemplateDeductionInfo &Info, | |||
3820 | SmallVectorImpl<DeducedTemplateArgument> &Deduced, | |||
3821 | SmallVectorImpl<Sema::OriginalCallArg> &OriginalCallArgs, | |||
3822 | bool DecomposedParam, unsigned ArgIdx, unsigned TDF); | |||
3823 | ||||
3824 | /// Attempt template argument deduction from an initializer list | |||
3825 | /// deemed to be an argument in a function call. | |||
3826 | static Sema::TemplateDeductionResult DeduceFromInitializerList( | |||
3827 | Sema &S, TemplateParameterList *TemplateParams, QualType AdjustedParamType, | |||
3828 | InitListExpr *ILE, TemplateDeductionInfo &Info, | |||
3829 | SmallVectorImpl<DeducedTemplateArgument> &Deduced, | |||
3830 | SmallVectorImpl<Sema::OriginalCallArg> &OriginalCallArgs, unsigned ArgIdx, | |||
3831 | unsigned TDF) { | |||
3832 | // C++ [temp.deduct.call]p1: (CWG 1591) | |||
3833 | // If removing references and cv-qualifiers from P gives | |||
3834 | // std::initializer_list<P0> or P0[N] for some P0 and N and the argument is | |||
3835 | // a non-empty initializer list, then deduction is performed instead for | |||
3836 | // each element of the initializer list, taking P0 as a function template | |||
3837 | // parameter type and the initializer element as its argument | |||
3838 | // | |||
3839 | // We've already removed references and cv-qualifiers here. | |||
3840 | if (!ILE->getNumInits()) | |||
3841 | return Sema::TDK_Success; | |||
3842 | ||||
3843 | QualType ElTy; | |||
3844 | auto *ArrTy = S.Context.getAsArrayType(AdjustedParamType); | |||
3845 | if (ArrTy) | |||
3846 | ElTy = ArrTy->getElementType(); | |||
3847 | else if (!S.isStdInitializerList(AdjustedParamType, &ElTy)) { | |||
3848 | // Otherwise, an initializer list argument causes the parameter to be | |||
3849 | // considered a non-deduced context | |||
3850 | return Sema::TDK_Success; | |||
3851 | } | |||
3852 | ||||
3853 | // Resolving a core issue: a braced-init-list containing any designators is | |||
3854 | // a non-deduced context. | |||
3855 | for (Expr *E : ILE->inits()) | |||
3856 | if (isa<DesignatedInitExpr>(E)) | |||
3857 | return Sema::TDK_Success; | |||
3858 | ||||
3859 | // Deduction only needs to be done for dependent types. | |||
3860 | if (ElTy->isDependentType()) { | |||
3861 | for (Expr *E : ILE->inits()) { | |||
3862 | if (auto Result = DeduceTemplateArgumentsFromCallArgument( | |||
3863 | S, TemplateParams, 0, ElTy, E, Info, Deduced, OriginalCallArgs, true, | |||
3864 | ArgIdx, TDF)) | |||
3865 | return Result; | |||
3866 | } | |||
3867 | } | |||
3868 | ||||
3869 | // in the P0[N] case, if N is a non-type template parameter, N is deduced | |||
3870 | // from the length of the initializer list. | |||
3871 | if (auto *DependentArrTy = dyn_cast_or_null<DependentSizedArrayType>(ArrTy)) { | |||
3872 | // Determine the array bound is something we can deduce. | |||
3873 | if (const NonTypeTemplateParmDecl *NTTP = | |||
3874 | getDeducedParameterFromExpr(Info, DependentArrTy->getSizeExpr())) { | |||
3875 | // We can perform template argument deduction for the given non-type | |||
3876 | // template parameter. | |||
3877 | // C++ [temp.deduct.type]p13: | |||
3878 | // The type of N in the type T[N] is std::size_t. | |||
3879 | QualType T = S.Context.getSizeType(); | |||
3880 | llvm::APInt Size(S.Context.getIntWidth(T), ILE->getNumInits()); | |||
3881 | if (auto Result = DeduceNonTypeTemplateArgument( | |||
3882 | S, TemplateParams, NTTP, llvm::APSInt(Size), T, | |||
3883 | /*ArrayBound=*/true, Info, Deduced)) | |||
3884 | return Result; | |||
3885 | } | |||
3886 | } | |||
3887 | ||||
3888 | return Sema::TDK_Success; | |||
3889 | } | |||
3890 | ||||
3891 | /// Perform template argument deduction per [temp.deduct.call] for a | |||
3892 | /// single parameter / argument pair. | |||
3893 | static Sema::TemplateDeductionResult DeduceTemplateArgumentsFromCallArgument( | |||
3894 | Sema &S, TemplateParameterList *TemplateParams, unsigned FirstInnerIndex, | |||
3895 | QualType ParamType, Expr *Arg, TemplateDeductionInfo &Info, | |||
3896 | SmallVectorImpl<DeducedTemplateArgument> &Deduced, | |||
3897 | SmallVectorImpl<Sema::OriginalCallArg> &OriginalCallArgs, | |||
3898 | bool DecomposedParam, unsigned ArgIdx, unsigned TDF) { | |||
3899 | QualType ArgType = Arg->getType(); | |||
3900 | QualType OrigParamType = ParamType; | |||
3901 | ||||
3902 | // If P is a reference type [...] | |||
3903 | // If P is a cv-qualified type [...] | |||
3904 | if (AdjustFunctionParmAndArgTypesForDeduction( | |||
3905 | S, TemplateParams, FirstInnerIndex, ParamType, ArgType, Arg, TDF)) | |||
3906 | return Sema::TDK_Success; | |||
3907 | ||||
3908 | // If [...] the argument is a non-empty initializer list [...] | |||
3909 | if (InitListExpr *ILE = dyn_cast<InitListExpr>(Arg)) | |||
3910 | return DeduceFromInitializerList(S, TemplateParams, ParamType, ILE, Info, | |||
3911 | Deduced, OriginalCallArgs, ArgIdx, TDF); | |||
3912 | ||||
3913 | // [...] the deduction process attempts to find template argument values | |||
3914 | // that will make the deduced A identical to A | |||
3915 | // | |||
3916 | // Keep track of the argument type and corresponding parameter index, | |||
3917 | // so we can check for compatibility between the deduced A and A. | |||
3918 | OriginalCallArgs.push_back( | |||
3919 | Sema::OriginalCallArg(OrigParamType, DecomposedParam, ArgIdx, ArgType)); | |||
3920 | return DeduceTemplateArgumentsByTypeMatch(S, TemplateParams, ParamType, | |||
3921 | ArgType, Info, Deduced, TDF); | |||
3922 | } | |||
3923 | ||||
3924 | /// Perform template argument deduction from a function call | |||
3925 | /// (C++ [temp.deduct.call]). | |||
3926 | /// | |||
3927 | /// \param FunctionTemplate the function template for which we are performing | |||
3928 | /// template argument deduction. | |||
3929 | /// | |||
3930 | /// \param ExplicitTemplateArgs the explicit template arguments provided | |||
3931 | /// for this call. | |||
3932 | /// | |||
3933 | /// \param Args the function call arguments | |||
3934 | /// | |||
3935 | /// \param Specialization if template argument deduction was successful, | |||
3936 | /// this will be set to the function template specialization produced by | |||
3937 | /// template argument deduction. | |||
3938 | /// | |||
3939 | /// \param Info the argument will be updated to provide additional information | |||
3940 | /// about template argument deduction. | |||
3941 | /// | |||
3942 | /// \param CheckNonDependent A callback to invoke to check conversions for | |||
3943 | /// non-dependent parameters, between deduction and substitution, per DR1391. | |||
3944 | /// If this returns true, substitution will be skipped and we return | |||
3945 | /// TDK_NonDependentConversionFailure. The callback is passed the parameter | |||
3946 | /// types (after substituting explicit template arguments). | |||
3947 | /// | |||
3948 | /// \returns the result of template argument deduction. | |||
3949 | Sema::TemplateDeductionResult Sema::DeduceTemplateArguments( | |||
3950 | FunctionTemplateDecl *FunctionTemplate, | |||
3951 | TemplateArgumentListInfo *ExplicitTemplateArgs, ArrayRef<Expr *> Args, | |||
3952 | FunctionDecl *&Specialization, TemplateDeductionInfo &Info, | |||
3953 | bool PartialOverloading, | |||
3954 | llvm::function_ref<bool(ArrayRef<QualType>)> CheckNonDependent) { | |||
3955 | if (FunctionTemplate->isInvalidDecl()) | |||
3956 | return TDK_Invalid; | |||
3957 | ||||
3958 | FunctionDecl *Function = FunctionTemplate->getTemplatedDecl(); | |||
3959 | unsigned NumParams = Function->getNumParams(); | |||
3960 | ||||
3961 | unsigned FirstInnerIndex = getFirstInnerIndex(FunctionTemplate); | |||
3962 | ||||
3963 | // C++ [temp.deduct.call]p1: | |||
3964 | // Template argument deduction is done by comparing each function template | |||
3965 | // parameter type (call it P) with the type of the corresponding argument | |||
3966 | // of the call (call it A) as described below. | |||
3967 | if (Args.size() < Function->getMinRequiredArguments() && !PartialOverloading) | |||
3968 | return TDK_TooFewArguments; | |||
3969 | else if (TooManyArguments(NumParams, Args.size(), PartialOverloading)) { | |||
3970 | const auto *Proto = Function->getType()->castAs<FunctionProtoType>(); | |||
3971 | if (Proto->isTemplateVariadic()) | |||
3972 | /* Do nothing */; | |||
3973 | else if (!Proto->isVariadic()) | |||
3974 | return TDK_TooManyArguments; | |||
3975 | } | |||
3976 | ||||
3977 | // The types of the parameters from which we will perform template argument | |||
3978 | // deduction. | |||
3979 | LocalInstantiationScope InstScope(*this); | |||
3980 | TemplateParameterList *TemplateParams | |||
3981 | = FunctionTemplate->getTemplateParameters(); | |||
3982 | SmallVector<DeducedTemplateArgument, 4> Deduced; | |||
3983 | SmallVector<QualType, 8> ParamTypes; | |||
3984 | unsigned NumExplicitlySpecified = 0; | |||
3985 | if (ExplicitTemplateArgs) { | |||
3986 | TemplateDeductionResult Result; | |||
3987 | runWithSufficientStackSpace(Info.getLocation(), [&] { | |||
3988 | Result = SubstituteExplicitTemplateArguments( | |||
3989 | FunctionTemplate, *ExplicitTemplateArgs, Deduced, ParamTypes, nullptr, | |||
3990 | Info); | |||
3991 | }); | |||
3992 | if (Result) | |||
3993 | return Result; | |||
3994 | ||||
3995 | NumExplicitlySpecified = Deduced.size(); | |||
3996 | } else { | |||
3997 | // Just fill in the parameter types from the function declaration. | |||
3998 | for (unsigned I = 0; I != NumParams; ++I) | |||
3999 | ParamTypes.push_back(Function->getParamDecl(I)->getType()); | |||
4000 | } | |||
4001 | ||||
4002 | SmallVector<OriginalCallArg, 8> OriginalCallArgs; | |||
4003 | ||||
4004 | // Deduce an argument of type ParamType from an expression with index ArgIdx. | |||
4005 | auto DeduceCallArgument = [&](QualType ParamType, unsigned ArgIdx) { | |||
4006 | // C++ [demp.deduct.call]p1: (DR1391) | |||
4007 | // Template argument deduction is done by comparing each function template | |||
4008 | // parameter that contains template-parameters that participate in | |||
4009 | // template argument deduction ... | |||
4010 | if (!hasDeducibleTemplateParameters(*this, FunctionTemplate, ParamType)) | |||
4011 | return Sema::TDK_Success; | |||
4012 | ||||
4013 | // ... with the type of the corresponding argument | |||
4014 | return DeduceTemplateArgumentsFromCallArgument( | |||
4015 | *this, TemplateParams, FirstInnerIndex, ParamType, Args[ArgIdx], Info, Deduced, | |||
4016 | OriginalCallArgs, /*Decomposed*/false, ArgIdx, /*TDF*/ 0); | |||
4017 | }; | |||
4018 | ||||
4019 | // Deduce template arguments from the function parameters. | |||
4020 | Deduced.resize(TemplateParams->size()); | |||
4021 | SmallVector<QualType, 8> ParamTypesForArgChecking; | |||
4022 | for (unsigned ParamIdx = 0, NumParamTypes = ParamTypes.size(), ArgIdx = 0; | |||
4023 | ParamIdx != NumParamTypes; ++ParamIdx) { | |||
4024 | QualType ParamType = ParamTypes[ParamIdx]; | |||
4025 | ||||
4026 | const PackExpansionType *ParamExpansion = | |||
4027 | dyn_cast<PackExpansionType>(ParamType); | |||
4028 | if (!ParamExpansion) { | |||
4029 | // Simple case: matching a function parameter to a function argument. | |||
4030 | if (ArgIdx >= Args.size()) | |||
4031 | break; | |||
4032 | ||||
4033 | ParamTypesForArgChecking.push_back(ParamType); | |||
4034 | if (auto Result = DeduceCallArgument(ParamType, ArgIdx++)) | |||
4035 | return Result; | |||
4036 | ||||
4037 | continue; | |||
4038 | } | |||
4039 | ||||
4040 | QualType ParamPattern = ParamExpansion->getPattern(); | |||
4041 | PackDeductionScope PackScope(*this, TemplateParams, Deduced, Info, | |||
4042 | ParamPattern); | |||
4043 | ||||
4044 | // C++0x [temp.deduct.call]p1: | |||
4045 | // For a function parameter pack that occurs at the end of the | |||
4046 | // parameter-declaration-list, the type A of each remaining argument of | |||
4047 | // the call is compared with the type P of the declarator-id of the | |||
4048 | // function parameter pack. Each comparison deduces template arguments | |||
4049 | // for subsequent positions in the template parameter packs expanded by | |||
4050 | // the function parameter pack. When a function parameter pack appears | |||
4051 | // in a non-deduced context [not at the end of the list], the type of | |||
4052 | // that parameter pack is never deduced. | |||
4053 | // | |||
4054 | // FIXME: The above rule allows the size of the parameter pack to change | |||
4055 | // after we skip it (in the non-deduced case). That makes no sense, so | |||
4056 | // we instead notionally deduce the pack against N arguments, where N is | |||
4057 | // the length of the explicitly-specified pack if it's expanded by the | |||
4058 | // parameter pack and 0 otherwise, and we treat each deduction as a | |||
4059 | // non-deduced context. | |||
4060 | if (ParamIdx + 1 == NumParamTypes || PackScope.hasFixedArity()) { | |||
4061 | for (; ArgIdx < Args.size() && PackScope.hasNextElement(); | |||
4062 | PackScope.nextPackElement(), ++ArgIdx) { | |||
4063 | ParamTypesForArgChecking.push_back(ParamPattern); | |||
4064 | if (auto Result = DeduceCallArgument(ParamPattern, ArgIdx)) | |||
4065 | return Result; | |||
4066 | } | |||
4067 | } else { | |||
4068 | // If the parameter type contains an explicitly-specified pack that we | |||
4069 | // could not expand, skip the number of parameters notionally created | |||
4070 | // by the expansion. | |||
4071 | Optional<unsigned> NumExpansions = ParamExpansion->getNumExpansions(); | |||
4072 | if (NumExpansions && !PackScope.isPartiallyExpanded()) { | |||
4073 | for (unsigned I = 0; I != *NumExpansions && ArgIdx < Args.size(); | |||
4074 | ++I, ++ArgIdx) { | |||
4075 | ParamTypesForArgChecking.push_back(ParamPattern); | |||
4076 | // FIXME: Should we add OriginalCallArgs for these? What if the | |||
4077 | // corresponding argument is a list? | |||
4078 | PackScope.nextPackElement(); | |||
4079 | } | |||
4080 | } | |||
4081 | } | |||
4082 | ||||
4083 | // Build argument packs for each of the parameter packs expanded by this | |||
4084 | // pack expansion. | |||
4085 | if (auto Result = PackScope.finish()) | |||
4086 | return Result; | |||
4087 | } | |||
4088 | ||||
4089 | // Capture the context in which the function call is made. This is the context | |||
4090 | // that is needed when the accessibility of template arguments is checked. | |||
4091 | DeclContext *CallingCtx = CurContext; | |||
4092 | ||||
4093 | TemplateDeductionResult Result; | |||
4094 | runWithSufficientStackSpace(Info.getLocation(), [&] { | |||
4095 | Result = FinishTemplateArgumentDeduction( | |||
4096 | FunctionTemplate, Deduced, NumExplicitlySpecified, Specialization, Info, | |||
4097 | &OriginalCallArgs, PartialOverloading, [&, CallingCtx]() { | |||
4098 | ContextRAII SavedContext(*this, CallingCtx); | |||
4099 | return CheckNonDependent(ParamTypesForArgChecking); | |||
4100 | }); | |||
4101 | }); | |||
4102 | return Result; | |||
4103 | } | |||
4104 | ||||
4105 | QualType Sema::adjustCCAndNoReturn(QualType ArgFunctionType, | |||
4106 | QualType FunctionType, | |||
4107 | bool AdjustExceptionSpec) { | |||
4108 | if (ArgFunctionType.isNull()) | |||
4109 | return ArgFunctionType; | |||
4110 | ||||
4111 | const auto *FunctionTypeP = FunctionType->castAs<FunctionProtoType>(); | |||
4112 | const auto *ArgFunctionTypeP = ArgFunctionType->castAs<FunctionProtoType>(); | |||
4113 | FunctionProtoType::ExtProtoInfo EPI = ArgFunctionTypeP->getExtProtoInfo(); | |||
4114 | bool Rebuild = false; | |||
4115 | ||||
4116 | CallingConv CC = FunctionTypeP->getCallConv(); | |||
4117 | if (EPI.ExtInfo.getCC() != CC) { | |||
4118 | EPI.ExtInfo = EPI.ExtInfo.withCallingConv(CC); | |||
4119 | Rebuild = true; | |||
4120 | } | |||
4121 | ||||
4122 | bool NoReturn = FunctionTypeP->getNoReturnAttr(); | |||
4123 | if (EPI.ExtInfo.getNoReturn() != NoReturn) { | |||
4124 | EPI.ExtInfo = EPI.ExtInfo.withNoReturn(NoReturn); | |||
4125 | Rebuild = true; | |||
4126 | } | |||
4127 | ||||
4128 | if (AdjustExceptionSpec && (FunctionTypeP->hasExceptionSpec() || | |||
4129 | ArgFunctionTypeP->hasExceptionSpec())) { | |||
4130 | EPI.ExceptionSpec = FunctionTypeP->getExtProtoInfo().ExceptionSpec; | |||
4131 | Rebuild = true; | |||
4132 | } | |||
4133 | ||||
4134 | if (!Rebuild) | |||
4135 | return ArgFunctionType; | |||
4136 | ||||
4137 | return Context.getFunctionType(ArgFunctionTypeP->getReturnType(), | |||
4138 | ArgFunctionTypeP->getParamTypes(), EPI); | |||
4139 | } | |||
4140 | ||||
4141 | /// Deduce template arguments when taking the address of a function | |||
4142 | /// template (C++ [temp.deduct.funcaddr]) or matching a specialization to | |||
4143 | /// a template. | |||
4144 | /// | |||
4145 | /// \param FunctionTemplate the function template for which we are performing | |||
4146 | /// template argument deduction. | |||
4147 | /// | |||
4148 | /// \param ExplicitTemplateArgs the explicitly-specified template | |||
4149 | /// arguments. | |||
4150 | /// | |||
4151 | /// \param ArgFunctionType the function type that will be used as the | |||
4152 | /// "argument" type (A) when performing template argument deduction from the | |||
4153 | /// function template's function type. This type may be NULL, if there is no | |||
4154 | /// argument type to compare against, in C++0x [temp.arg.explicit]p3. | |||
4155 | /// | |||
4156 | /// \param Specialization if template argument deduction was successful, | |||
4157 | /// this will be set to the function template specialization produced by | |||
4158 | /// template argument deduction. | |||
4159 | /// | |||
4160 | /// \param Info the argument will be updated to provide additional information | |||
4161 | /// about template argument deduction. | |||
4162 | /// | |||
4163 | /// \param IsAddressOfFunction If \c true, we are deducing as part of taking | |||
4164 | /// the address of a function template per [temp.deduct.funcaddr] and | |||
4165 | /// [over.over]. If \c false, we are looking up a function template | |||
4166 | /// specialization based on its signature, per [temp.deduct.decl]. | |||
4167 | /// | |||
4168 | /// \returns the result of template argument deduction. | |||
4169 | Sema::TemplateDeductionResult Sema::DeduceTemplateArguments( | |||
4170 | FunctionTemplateDecl *FunctionTemplate, | |||
4171 | TemplateArgumentListInfo *ExplicitTemplateArgs, QualType ArgFunctionType, | |||
4172 | FunctionDecl *&Specialization, TemplateDeductionInfo &Info, | |||
4173 | bool IsAddressOfFunction) { | |||
4174 | if (FunctionTemplate->isInvalidDecl()) | |||
4175 | return TDK_Invalid; | |||
4176 | ||||
4177 | FunctionDecl *Function = FunctionTemplate->getTemplatedDecl(); | |||
4178 | TemplateParameterList *TemplateParams | |||
4179 | = FunctionTemplate->getTemplateParameters(); | |||
4180 | QualType FunctionType = Function->getType(); | |||
4181 | ||||
4182 | // Substitute any explicit template arguments. | |||
4183 | LocalInstantiationScope InstScope(*this); | |||
4184 | SmallVector<DeducedTemplateArgument, 4> Deduced; | |||
4185 | unsigned NumExplicitlySpecified = 0; | |||
4186 | SmallVector<QualType, 4> ParamTypes; | |||
4187 | if (ExplicitTemplateArgs) { | |||
4188 | TemplateDeductionResult Result; | |||
4189 | runWithSufficientStackSpace(Info.getLocation(), [&] { | |||
4190 | Result = SubstituteExplicitTemplateArguments( | |||
4191 | FunctionTemplate, *ExplicitTemplateArgs, Deduced, ParamTypes, | |||
4192 | &FunctionType, Info); | |||
4193 | }); | |||
4194 | if (Result) | |||
4195 | return Result; | |||
4196 | ||||
4197 | NumExplicitlySpecified = Deduced.size(); | |||
4198 | } | |||
4199 | ||||
4200 | // When taking the address of a function, we require convertibility of | |||
4201 | // the resulting function type. Otherwise, we allow arbitrary mismatches | |||
4202 | // of calling convention and noreturn. | |||
4203 | if (!IsAddressOfFunction) | |||
4204 | ArgFunctionType = adjustCCAndNoReturn(ArgFunctionType, FunctionType, | |||
4205 | /*AdjustExceptionSpec*/false); | |||
4206 | ||||
4207 | // Unevaluated SFINAE context. | |||
4208 | EnterExpressionEvaluationContext Unevaluated( | |||
4209 | *this, Sema::ExpressionEvaluationContext::Unevaluated); | |||
4210 | SFINAETrap Trap(*this); | |||
4211 | ||||
4212 | Deduced.resize(TemplateParams->size()); | |||
4213 | ||||
4214 | // If the function has a deduced return type, substitute it for a dependent | |||
4215 | // type so that we treat it as a non-deduced context in what follows. If we | |||
4216 | // are looking up by signature, the signature type should also have a deduced | |||
4217 | // return type, which we instead expect to exactly match. | |||
4218 | bool HasDeducedReturnType = false; | |||
4219 | if (getLangOpts().CPlusPlus14 && IsAddressOfFunction && | |||
4220 | Function->getReturnType()->getContainedAutoType()) { | |||
4221 | FunctionType = SubstAutoTypeDependent(FunctionType); | |||
4222 | HasDeducedReturnType = true; | |||
4223 | } | |||
4224 | ||||
4225 | if (!ArgFunctionType.isNull() && !FunctionType.isNull()) { | |||
4226 | unsigned TDF = | |||
4227 | TDF_TopLevelParameterTypeList | TDF_AllowCompatibleFunctionType; | |||
4228 | // Deduce template arguments from the function type. | |||
4229 | if (TemplateDeductionResult Result | |||
4230 | = DeduceTemplateArgumentsByTypeMatch(*this, TemplateParams, | |||
4231 | FunctionType, ArgFunctionType, | |||
4232 | Info, Deduced, TDF)) | |||
4233 | return Result; | |||
4234 | } | |||
4235 | ||||
4236 | TemplateDeductionResult Result; | |||
4237 | runWithSufficientStackSpace(Info.getLocation(), [&] { | |||
4238 | Result = FinishTemplateArgumentDeduction(FunctionTemplate, Deduced, | |||
4239 | NumExplicitlySpecified, | |||
4240 | Specialization, Info); | |||
4241 | }); | |||
4242 | if (Result) | |||
4243 | return Result; | |||
4244 | ||||
4245 | // If the function has a deduced return type, deduce it now, so we can check | |||
4246 | // that the deduced function type matches the requested type. | |||
4247 | if (HasDeducedReturnType && | |||
4248 | Specialization->getReturnType()->isUndeducedType() && | |||
4249 | DeduceReturnType(Specialization, Info.getLocation(), false)) | |||
4250 | return TDK_MiscellaneousDeductionFailure; | |||
4251 | ||||
4252 | // If the function has a dependent exception specification, resolve it now, | |||
4253 | // so we can check that the exception specification matches. | |||
4254 | auto *SpecializationFPT = | |||
4255 | Specialization->getType()->castAs<FunctionProtoType>(); | |||
4256 | if (getLangOpts().CPlusPlus17 && | |||
4257 | isUnresolvedExceptionSpec(SpecializationFPT->getExceptionSpecType()) && | |||
4258 | !ResolveExceptionSpec(Info.getLocation(), SpecializationFPT)) | |||
4259 | return TDK_MiscellaneousDeductionFailure; | |||
4260 | ||||
4261 | // Adjust the exception specification of the argument to match the | |||
4262 | // substituted and resolved type we just formed. (Calling convention and | |||
4263 | // noreturn can't be dependent, so we don't actually need this for them | |||
4264 | // right now.) | |||
4265 | QualType SpecializationType = Specialization->getType(); | |||
4266 | if (!IsAddressOfFunction) | |||
4267 | ArgFunctionType = adjustCCAndNoReturn(ArgFunctionType, SpecializationType, | |||
4268 | /*AdjustExceptionSpec*/true); | |||
4269 | ||||
4270 | // If the requested function type does not match the actual type of the | |||
4271 | // specialization with respect to arguments of compatible pointer to function | |||
4272 | // types, template argument deduction fails. | |||
4273 | if (!ArgFunctionType.isNull()) { | |||
4274 | if (IsAddressOfFunction && | |||
4275 | !isSameOrCompatibleFunctionType( | |||
4276 | Context.getCanonicalType(SpecializationType), | |||
4277 | Context.getCanonicalType(ArgFunctionType))) | |||
4278 | return TDK_MiscellaneousDeductionFailure; | |||
4279 | ||||
4280 | if (!IsAddressOfFunction && | |||
4281 | !Context.hasSameType(SpecializationType, ArgFunctionType)) | |||
4282 | return TDK_MiscellaneousDeductionFailure; | |||
4283 | } | |||
4284 | ||||
4285 | return TDK_Success; | |||
4286 | } | |||
4287 | ||||
4288 | /// Deduce template arguments for a templated conversion | |||
4289 | /// function (C++ [temp.deduct.conv]) and, if successful, produce a | |||
4290 | /// conversion function template specialization. | |||
4291 | Sema::TemplateDeductionResult | |||
4292 | Sema::DeduceTemplateArguments(FunctionTemplateDecl *ConversionTemplate, | |||
4293 | QualType ToType, | |||
4294 | CXXConversionDecl *&Specialization, | |||
4295 | TemplateDeductionInfo &Info) { | |||
4296 | if (ConversionTemplate->isInvalidDecl()) | |||
4297 | return TDK_Invalid; | |||
4298 | ||||
4299 | CXXConversionDecl *ConversionGeneric | |||
4300 | = cast<CXXConversionDecl>(ConversionTemplate->getTemplatedDecl()); | |||
4301 | ||||
4302 | QualType FromType = ConversionGeneric->getConversionType(); | |||
4303 | ||||
4304 | // Canonicalize the types for deduction. | |||
4305 | QualType P = Context.getCanonicalType(FromType); | |||
4306 | QualType A = Context.getCanonicalType(ToType); | |||
4307 | ||||
4308 | // C++0x [temp.deduct.conv]p2: | |||
4309 | // If P is a reference type, the type referred to by P is used for | |||
4310 | // type deduction. | |||
4311 | if (const ReferenceType *PRef = P->getAs<ReferenceType>()) | |||
4312 | P = PRef->getPointeeType(); | |||
4313 | ||||
4314 | // C++0x [temp.deduct.conv]p4: | |||
4315 | // [...] If A is a reference type, the type referred to by A is used | |||
4316 | // for type deduction. | |||
4317 | if (const ReferenceType *ARef = A->getAs<ReferenceType>()) { | |||
4318 | A = ARef->getPointeeType(); | |||
4319 | // We work around a defect in the standard here: cv-qualifiers are also | |||
4320 | // removed from P and A in this case, unless P was a reference type. This | |||
4321 | // seems to mostly match what other compilers are doing. | |||
4322 | if (!FromType->getAs<ReferenceType>()) { | |||
4323 | A = A.getUnqualifiedType(); | |||
4324 | P = P.getUnqualifiedType(); | |||
4325 | } | |||
4326 | ||||
4327 | // C++ [temp.deduct.conv]p3: | |||
4328 | // | |||
4329 | // If A is not a reference type: | |||
4330 | } else { | |||
4331 | assert(!A->isReferenceType() && "Reference types were handled above")(static_cast <bool> (!A->isReferenceType() && "Reference types were handled above") ? void (0) : __assert_fail ("!A->isReferenceType() && \"Reference types were handled above\"" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 4331, __extension__ __PRETTY_FUNCTION__)); | |||
4332 | ||||
4333 | // - If P is an array type, the pointer type produced by the | |||
4334 | // array-to-pointer standard conversion (4.2) is used in place | |||
4335 | // of P for type deduction; otherwise, | |||
4336 | if (P->isArrayType()) | |||
4337 | P = Context.getArrayDecayedType(P); | |||
4338 | // - If P is a function type, the pointer type produced by the | |||
4339 | // function-to-pointer standard conversion (4.3) is used in | |||
4340 | // place of P for type deduction; otherwise, | |||
4341 | else if (P->isFunctionType()) | |||
4342 | P = Context.getPointerType(P); | |||
4343 | // - If P is a cv-qualified type, the top level cv-qualifiers of | |||
4344 | // P's type are ignored for type deduction. | |||
4345 | else | |||
4346 | P = P.getUnqualifiedType(); | |||
4347 | ||||
4348 | // C++0x [temp.deduct.conv]p4: | |||
4349 | // If A is a cv-qualified type, the top level cv-qualifiers of A's | |||
4350 | // type are ignored for type deduction. If A is a reference type, the type | |||
4351 | // referred to by A is used for type deduction. | |||
4352 | A = A.getUnqualifiedType(); | |||
4353 | } | |||
4354 | ||||
4355 | // Unevaluated SFINAE context. | |||
4356 | EnterExpressionEvaluationContext Unevaluated( | |||
4357 | *this, Sema::ExpressionEvaluationContext::Unevaluated); | |||
4358 | SFINAETrap Trap(*this); | |||
4359 | ||||
4360 | // C++ [temp.deduct.conv]p1: | |||
4361 | // Template argument deduction is done by comparing the return | |||
4362 | // type of the template conversion function (call it P) with the | |||
4363 | // type that is required as the result of the conversion (call it | |||
4364 | // A) as described in 14.8.2.4. | |||
4365 | TemplateParameterList *TemplateParams | |||
4366 | = ConversionTemplate->getTemplateParameters(); | |||
4367 | SmallVector<DeducedTemplateArgument, 4> Deduced; | |||
4368 | Deduced.resize(TemplateParams->size()); | |||
4369 | ||||
4370 | // C++0x [temp.deduct.conv]p4: | |||
4371 | // In general, the deduction process attempts to find template | |||
4372 | // argument values that will make the deduced A identical to | |||
4373 | // A. However, there are two cases that allow a difference: | |||
4374 | unsigned TDF = 0; | |||
4375 | // - If the original A is a reference type, A can be more | |||
4376 | // cv-qualified than the deduced A (i.e., the type referred to | |||
4377 | // by the reference) | |||
4378 | if (ToType->isReferenceType()) | |||
4379 | TDF |= TDF_ArgWithReferenceType; | |||
4380 | // - The deduced A can be another pointer or pointer to member | |||
4381 | // type that can be converted to A via a qualification | |||
4382 | // conversion. | |||
4383 | // | |||
4384 | // (C++0x [temp.deduct.conv]p6 clarifies that this only happens when | |||
4385 | // both P and A are pointers or member pointers. In this case, we | |||
4386 | // just ignore cv-qualifiers completely). | |||
4387 | if ((P->isPointerType() && A->isPointerType()) || | |||
4388 | (P->isMemberPointerType() && A->isMemberPointerType())) | |||
4389 | TDF |= TDF_IgnoreQualifiers; | |||
4390 | if (TemplateDeductionResult Result | |||
4391 | = DeduceTemplateArgumentsByTypeMatch(*this, TemplateParams, | |||
4392 | P, A, Info, Deduced, TDF)) | |||
4393 | return Result; | |||
4394 | ||||
4395 | // Create an Instantiation Scope for finalizing the operator. | |||
4396 | LocalInstantiationScope InstScope(*this); | |||
4397 | // Finish template argument deduction. | |||
4398 | FunctionDecl *ConversionSpecialized = nullptr; | |||
4399 | TemplateDeductionResult Result; | |||
4400 | runWithSufficientStackSpace(Info.getLocation(), [&] { | |||
4401 | Result = FinishTemplateArgumentDeduction(ConversionTemplate, Deduced, 0, | |||
4402 | ConversionSpecialized, Info); | |||
4403 | }); | |||
4404 | Specialization = cast_or_null<CXXConversionDecl>(ConversionSpecialized); | |||
4405 | return Result; | |||
4406 | } | |||
4407 | ||||
4408 | /// Deduce template arguments for a function template when there is | |||
4409 | /// nothing to deduce against (C++0x [temp.arg.explicit]p3). | |||
4410 | /// | |||
4411 | /// \param FunctionTemplate the function template for which we are performing | |||
4412 | /// template argument deduction. | |||
4413 | /// | |||
4414 | /// \param ExplicitTemplateArgs the explicitly-specified template | |||
4415 | /// arguments. | |||
4416 | /// | |||
4417 | /// \param Specialization if template argument deduction was successful, | |||
4418 | /// this will be set to the function template specialization produced by | |||
4419 | /// template argument deduction. | |||
4420 | /// | |||
4421 | /// \param Info the argument will be updated to provide additional information | |||
4422 | /// about template argument deduction. | |||
4423 | /// | |||
4424 | /// \param IsAddressOfFunction If \c true, we are deducing as part of taking | |||
4425 | /// the address of a function template in a context where we do not have a | |||
4426 | /// target type, per [over.over]. If \c false, we are looking up a function | |||
4427 | /// template specialization based on its signature, which only happens when | |||
4428 | /// deducing a function parameter type from an argument that is a template-id | |||
4429 | /// naming a function template specialization. | |||
4430 | /// | |||
4431 | /// \returns the result of template argument deduction. | |||
4432 | Sema::TemplateDeductionResult Sema::DeduceTemplateArguments( | |||
4433 | FunctionTemplateDecl *FunctionTemplate, | |||
4434 | TemplateArgumentListInfo *ExplicitTemplateArgs, | |||
4435 | FunctionDecl *&Specialization, TemplateDeductionInfo &Info, | |||
4436 | bool IsAddressOfFunction) { | |||
4437 | return DeduceTemplateArguments(FunctionTemplate, ExplicitTemplateArgs, | |||
4438 | QualType(), Specialization, Info, | |||
4439 | IsAddressOfFunction); | |||
4440 | } | |||
4441 | ||||
4442 | namespace { | |||
4443 | struct DependentAuto { bool IsPack; }; | |||
4444 | ||||
4445 | /// Substitute the 'auto' specifier or deduced template specialization type | |||
4446 | /// specifier within a type for a given replacement type. | |||
4447 | class SubstituteDeducedTypeTransform : | |||
4448 | public TreeTransform<SubstituteDeducedTypeTransform> { | |||
4449 | QualType Replacement; | |||
4450 | bool ReplacementIsPack; | |||
4451 | bool UseTypeSugar; | |||
4452 | ||||
4453 | public: | |||
4454 | SubstituteDeducedTypeTransform(Sema &SemaRef, DependentAuto DA) | |||
4455 | : TreeTransform<SubstituteDeducedTypeTransform>(SemaRef), | |||
4456 | ReplacementIsPack(DA.IsPack), UseTypeSugar(true) {} | |||
4457 | ||||
4458 | SubstituteDeducedTypeTransform(Sema &SemaRef, QualType Replacement, | |||
4459 | bool UseTypeSugar = true) | |||
4460 | : TreeTransform<SubstituteDeducedTypeTransform>(SemaRef), | |||
4461 | Replacement(Replacement), ReplacementIsPack(false), | |||
4462 | UseTypeSugar(UseTypeSugar) {} | |||
4463 | ||||
4464 | QualType TransformDesugared(TypeLocBuilder &TLB, DeducedTypeLoc TL) { | |||
4465 | assert(isa<TemplateTypeParmType>(Replacement) &&(static_cast <bool> (isa<TemplateTypeParmType>(Replacement ) && "unexpected unsugared replacement kind") ? void ( 0) : __assert_fail ("isa<TemplateTypeParmType>(Replacement) && \"unexpected unsugared replacement kind\"" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 4466, __extension__ __PRETTY_FUNCTION__)) | |||
4466 | "unexpected unsugared replacement kind")(static_cast <bool> (isa<TemplateTypeParmType>(Replacement ) && "unexpected unsugared replacement kind") ? void ( 0) : __assert_fail ("isa<TemplateTypeParmType>(Replacement) && \"unexpected unsugared replacement kind\"" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 4466, __extension__ __PRETTY_FUNCTION__)); | |||
4467 | QualType Result = Replacement; | |||
4468 | TemplateTypeParmTypeLoc NewTL = TLB.push<TemplateTypeParmTypeLoc>(Result); | |||
4469 | NewTL.setNameLoc(TL.getNameLoc()); | |||
4470 | return Result; | |||
4471 | } | |||
4472 | ||||
4473 | QualType TransformAutoType(TypeLocBuilder &TLB, AutoTypeLoc TL) { | |||
4474 | // If we're building the type pattern to deduce against, don't wrap the | |||
4475 | // substituted type in an AutoType. Certain template deduction rules | |||
4476 | // apply only when a template type parameter appears directly (and not if | |||
4477 | // the parameter is found through desugaring). For instance: | |||
4478 | // auto &&lref = lvalue; | |||
4479 | // must transform into "rvalue reference to T" not "rvalue reference to | |||
4480 | // auto type deduced as T" in order for [temp.deduct.call]p3 to apply. | |||
4481 | // | |||
4482 | // FIXME: Is this still necessary? | |||
4483 | if (!UseTypeSugar) | |||
4484 | return TransformDesugared(TLB, TL); | |||
4485 | ||||
4486 | QualType Result = SemaRef.Context.getAutoType( | |||
4487 | Replacement, TL.getTypePtr()->getKeyword(), Replacement.isNull(), | |||
4488 | ReplacementIsPack, TL.getTypePtr()->getTypeConstraintConcept(), | |||
4489 | TL.getTypePtr()->getTypeConstraintArguments()); | |||
4490 | auto NewTL = TLB.push<AutoTypeLoc>(Result); | |||
4491 | NewTL.copy(TL); | |||
4492 | return Result; | |||
4493 | } | |||
4494 | ||||
4495 | QualType TransformDeducedTemplateSpecializationType( | |||
4496 | TypeLocBuilder &TLB, DeducedTemplateSpecializationTypeLoc TL) { | |||
4497 | if (!UseTypeSugar) | |||
4498 | return TransformDesugared(TLB, TL); | |||
4499 | ||||
4500 | QualType Result = SemaRef.Context.getDeducedTemplateSpecializationType( | |||
4501 | TL.getTypePtr()->getTemplateName(), | |||
4502 | Replacement, Replacement.isNull()); | |||
4503 | auto NewTL = TLB.push<DeducedTemplateSpecializationTypeLoc>(Result); | |||
4504 | NewTL.setNameLoc(TL.getNameLoc()); | |||
4505 | return Result; | |||
4506 | } | |||
4507 | ||||
4508 | ExprResult TransformLambdaExpr(LambdaExpr *E) { | |||
4509 | // Lambdas never need to be transformed. | |||
4510 | return E; | |||
4511 | } | |||
4512 | ||||
4513 | QualType Apply(TypeLoc TL) { | |||
4514 | // Create some scratch storage for the transformed type locations. | |||
4515 | // FIXME: We're just going to throw this information away. Don't build it. | |||
4516 | TypeLocBuilder TLB; | |||
4517 | TLB.reserve(TL.getFullDataSize()); | |||
4518 | return TransformType(TLB, TL); | |||
4519 | } | |||
4520 | }; | |||
4521 | ||||
4522 | } // namespace | |||
4523 | ||||
4524 | Sema::DeduceAutoResult | |||
4525 | Sema::DeduceAutoType(TypeSourceInfo *Type, Expr *&Init, QualType &Result, | |||
4526 | Optional<unsigned> DependentDeductionDepth, | |||
4527 | bool IgnoreConstraints) { | |||
4528 | return DeduceAutoType(Type->getTypeLoc(), Init, Result, | |||
4529 | DependentDeductionDepth, IgnoreConstraints); | |||
4530 | } | |||
4531 | ||||
4532 | /// Attempt to produce an informative diagostic explaining why auto deduction | |||
4533 | /// failed. | |||
4534 | /// \return \c true if diagnosed, \c false if not. | |||
4535 | static bool diagnoseAutoDeductionFailure(Sema &S, | |||
4536 | Sema::TemplateDeductionResult TDK, | |||
4537 | TemplateDeductionInfo &Info, | |||
4538 | ArrayRef<SourceRange> Ranges) { | |||
4539 | switch (TDK) { | |||
4540 | case Sema::TDK_Inconsistent: { | |||
4541 | // Inconsistent deduction means we were deducing from an initializer list. | |||
4542 | auto D = S.Diag(Info.getLocation(), diag::err_auto_inconsistent_deduction); | |||
4543 | D << Info.FirstArg << Info.SecondArg; | |||
4544 | for (auto R : Ranges) | |||
4545 | D << R; | |||
4546 | return true; | |||
4547 | } | |||
4548 | ||||
4549 | // FIXME: Are there other cases for which a custom diagnostic is more useful | |||
4550 | // than the basic "types don't match" diagnostic? | |||
4551 | ||||
4552 | default: | |||
4553 | return false; | |||
4554 | } | |||
4555 | } | |||
4556 | ||||
4557 | static Sema::DeduceAutoResult | |||
4558 | CheckDeducedPlaceholderConstraints(Sema &S, const AutoType &Type, | |||
4559 | AutoTypeLoc TypeLoc, QualType Deduced) { | |||
4560 | ConstraintSatisfaction Satisfaction; | |||
4561 | ConceptDecl *Concept = Type.getTypeConstraintConcept(); | |||
4562 | TemplateArgumentListInfo TemplateArgs(TypeLoc.getLAngleLoc(), | |||
4563 | TypeLoc.getRAngleLoc()); | |||
4564 | TemplateArgs.addArgument( | |||
4565 | TemplateArgumentLoc(TemplateArgument(Deduced), | |||
4566 | S.Context.getTrivialTypeSourceInfo( | |||
4567 | Deduced, TypeLoc.getNameLoc()))); | |||
4568 | for (unsigned I = 0, C = TypeLoc.getNumArgs(); I != C; ++I) | |||
4569 | TemplateArgs.addArgument(TypeLoc.getArgLoc(I)); | |||
4570 | ||||
4571 | llvm::SmallVector<TemplateArgument, 4> Converted; | |||
4572 | if (S.CheckTemplateArgumentList(Concept, SourceLocation(), TemplateArgs, | |||
4573 | /*PartialTemplateArgs=*/false, Converted)) | |||
4574 | return Sema::DAR_FailedAlreadyDiagnosed; | |||
4575 | if (S.CheckConstraintSatisfaction(Concept, {Concept->getConstraintExpr()}, | |||
4576 | Converted, TypeLoc.getLocalSourceRange(), | |||
4577 | Satisfaction)) | |||
4578 | return Sema::DAR_FailedAlreadyDiagnosed; | |||
4579 | if (!Satisfaction.IsSatisfied) { | |||
4580 | std::string Buf; | |||
4581 | llvm::raw_string_ostream OS(Buf); | |||
4582 | OS << "'" << Concept->getName(); | |||
4583 | if (TypeLoc.hasExplicitTemplateArgs()) { | |||
4584 | printTemplateArgumentList( | |||
4585 | OS, Type.getTypeConstraintArguments(), S.getPrintingPolicy(), | |||
4586 | Type.getTypeConstraintConcept()->getTemplateParameters()); | |||
4587 | } | |||
4588 | OS << "'"; | |||
4589 | OS.flush(); | |||
4590 | S.Diag(TypeLoc.getConceptNameLoc(), | |||
4591 | diag::err_placeholder_constraints_not_satisfied) | |||
4592 | << Deduced << Buf << TypeLoc.getLocalSourceRange(); | |||
4593 | S.DiagnoseUnsatisfiedConstraint(Satisfaction); | |||
4594 | return Sema::DAR_FailedAlreadyDiagnosed; | |||
4595 | } | |||
4596 | return Sema::DAR_Succeeded; | |||
4597 | } | |||
4598 | ||||
4599 | /// Deduce the type for an auto type-specifier (C++11 [dcl.spec.auto]p6) | |||
4600 | /// | |||
4601 | /// Note that this is done even if the initializer is dependent. (This is | |||
4602 | /// necessary to support partial ordering of templates using 'auto'.) | |||
4603 | /// A dependent type will be produced when deducing from a dependent type. | |||
4604 | /// | |||
4605 | /// \param Type the type pattern using the auto type-specifier. | |||
4606 | /// \param Init the initializer for the variable whose type is to be deduced. | |||
4607 | /// \param Result if type deduction was successful, this will be set to the | |||
4608 | /// deduced type. | |||
4609 | /// \param DependentDeductionDepth Set if we should permit deduction in | |||
4610 | /// dependent cases. This is necessary for template partial ordering with | |||
4611 | /// 'auto' template parameters. The value specified is the template | |||
4612 | /// parameter depth at which we should perform 'auto' deduction. | |||
4613 | /// \param IgnoreConstraints Set if we should not fail if the deduced type does | |||
4614 | /// not satisfy the type-constraint in the auto type. | |||
4615 | Sema::DeduceAutoResult | |||
4616 | Sema::DeduceAutoType(TypeLoc Type, Expr *&Init, QualType &Result, | |||
4617 | Optional<unsigned> DependentDeductionDepth, | |||
4618 | bool IgnoreConstraints) { | |||
4619 | if (Init->containsErrors()) | |||
4620 | return DAR_FailedAlreadyDiagnosed; | |||
4621 | if (Init->getType()->isNonOverloadPlaceholderType()) { | |||
4622 | ExprResult NonPlaceholder = CheckPlaceholderExpr(Init); | |||
4623 | if (NonPlaceholder.isInvalid()) | |||
4624 | return DAR_FailedAlreadyDiagnosed; | |||
4625 | Init = NonPlaceholder.get(); | |||
4626 | } | |||
4627 | ||||
4628 | DependentAuto DependentResult = { | |||
4629 | /*.IsPack = */ (bool)Type.getAs<PackExpansionTypeLoc>()}; | |||
4630 | ||||
4631 | if (!DependentDeductionDepth && | |||
4632 | (Type.getType()->isDependentType() || Init->isTypeDependent() || | |||
4633 | Init->containsUnexpandedParameterPack())) { | |||
4634 | Result = SubstituteDeducedTypeTransform(*this, DependentResult).Apply(Type); | |||
4635 | assert(!Result.isNull() && "substituting DependentTy can't fail")(static_cast <bool> (!Result.isNull() && "substituting DependentTy can't fail" ) ? void (0) : __assert_fail ("!Result.isNull() && \"substituting DependentTy can't fail\"" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 4635, __extension__ __PRETTY_FUNCTION__)); | |||
4636 | return DAR_Succeeded; | |||
4637 | } | |||
4638 | ||||
4639 | // Find the depth of template parameter to synthesize. | |||
4640 | unsigned Depth = DependentDeductionDepth.getValueOr(0); | |||
4641 | ||||
4642 | // If this is a 'decltype(auto)' specifier, do the decltype dance. | |||
4643 | // Since 'decltype(auto)' can only occur at the top of the type, we | |||
4644 | // don't need to go digging for it. | |||
4645 | if (const AutoType *AT = Type.getType()->getAs<AutoType>()) { | |||
4646 | if (AT->isDecltypeAuto()) { | |||
4647 | if (isa<InitListExpr>(Init)) { | |||
4648 | Diag(Init->getBeginLoc(), diag::err_decltype_auto_initializer_list); | |||
4649 | return DAR_FailedAlreadyDiagnosed; | |||
4650 | } | |||
4651 | ||||
4652 | ExprResult ER = CheckPlaceholderExpr(Init); | |||
4653 | if (ER.isInvalid()) | |||
4654 | return DAR_FailedAlreadyDiagnosed; | |||
4655 | QualType Deduced = getDecltypeForExpr(ER.get()); | |||
4656 | assert(!Deduced.isNull())(static_cast <bool> (!Deduced.isNull()) ? void (0) : __assert_fail ("!Deduced.isNull()", "clang/lib/Sema/SemaTemplateDeduction.cpp" , 4656, __extension__ __PRETTY_FUNCTION__)); | |||
4657 | if (AT->isConstrained() && !IgnoreConstraints) { | |||
4658 | auto ConstraintsResult = | |||
4659 | CheckDeducedPlaceholderConstraints(*this, *AT, | |||
4660 | Type.getContainedAutoTypeLoc(), | |||
4661 | Deduced); | |||
4662 | if (ConstraintsResult != DAR_Succeeded) | |||
4663 | return ConstraintsResult; | |||
4664 | } | |||
4665 | Result = SubstituteDeducedTypeTransform(*this, Deduced).Apply(Type); | |||
4666 | if (Result.isNull()) | |||
4667 | return DAR_FailedAlreadyDiagnosed; | |||
4668 | return DAR_Succeeded; | |||
4669 | } else if (!getLangOpts().CPlusPlus) { | |||
4670 | if (isa<InitListExpr>(Init)) { | |||
4671 | Diag(Init->getBeginLoc(), diag::err_auto_init_list_from_c); | |||
4672 | return DAR_FailedAlreadyDiagnosed; | |||
4673 | } | |||
4674 | } | |||
4675 | } | |||
4676 | ||||
4677 | SourceLocation Loc = Init->getExprLoc(); | |||
4678 | ||||
4679 | LocalInstantiationScope InstScope(*this); | |||
4680 | ||||
4681 | // Build template<class TemplParam> void Func(FuncParam); | |||
4682 | TemplateTypeParmDecl *TemplParam = TemplateTypeParmDecl::Create( | |||
4683 | Context, nullptr, SourceLocation(), Loc, Depth, 0, nullptr, false, false, | |||
4684 | false); | |||
4685 | QualType TemplArg = QualType(TemplParam->getTypeForDecl(), 0); | |||
4686 | NamedDecl *TemplParamPtr = TemplParam; | |||
4687 | FixedSizeTemplateParameterListStorage<1, false> TemplateParamsSt( | |||
4688 | Context, Loc, Loc, TemplParamPtr, Loc, nullptr); | |||
4689 | ||||
4690 | QualType FuncParam = | |||
4691 | SubstituteDeducedTypeTransform(*this, TemplArg, /*UseTypeSugar*/ true) | |||
4692 | .Apply(Type); | |||
4693 | assert(!FuncParam.isNull() &&(static_cast <bool> (!FuncParam.isNull() && "substituting template parameter for 'auto' failed" ) ? void (0) : __assert_fail ("!FuncParam.isNull() && \"substituting template parameter for 'auto' failed\"" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 4694, __extension__ __PRETTY_FUNCTION__)) | |||
4694 | "substituting template parameter for 'auto' failed")(static_cast <bool> (!FuncParam.isNull() && "substituting template parameter for 'auto' failed" ) ? void (0) : __assert_fail ("!FuncParam.isNull() && \"substituting template parameter for 'auto' failed\"" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 4694, __extension__ __PRETTY_FUNCTION__)); | |||
4695 | ||||
4696 | // Deduce type of TemplParam in Func(Init) | |||
4697 | SmallVector<DeducedTemplateArgument, 1> Deduced; | |||
4698 | Deduced.resize(1); | |||
4699 | ||||
4700 | TemplateDeductionInfo Info(Loc, Depth); | |||
4701 | ||||
4702 | // If deduction failed, don't diagnose if the initializer is dependent; it | |||
4703 | // might acquire a matching type in the instantiation. | |||
4704 | auto DeductionFailed = [&](TemplateDeductionResult TDK, | |||
4705 | ArrayRef<SourceRange> Ranges) -> DeduceAutoResult { | |||
4706 | if (Init->isTypeDependent()) { | |||
4707 | Result = | |||
4708 | SubstituteDeducedTypeTransform(*this, DependentResult).Apply(Type); | |||
4709 | assert(!Result.isNull() && "substituting DependentTy can't fail")(static_cast <bool> (!Result.isNull() && "substituting DependentTy can't fail" ) ? void (0) : __assert_fail ("!Result.isNull() && \"substituting DependentTy can't fail\"" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 4709, __extension__ __PRETTY_FUNCTION__)); | |||
4710 | return DAR_Succeeded; | |||
4711 | } | |||
4712 | if (diagnoseAutoDeductionFailure(*this, TDK, Info, Ranges)) | |||
4713 | return DAR_FailedAlreadyDiagnosed; | |||
4714 | return DAR_Failed; | |||
4715 | }; | |||
4716 | ||||
4717 | SmallVector<OriginalCallArg, 4> OriginalCallArgs; | |||
4718 | ||||
4719 | InitListExpr *InitList = dyn_cast<InitListExpr>(Init); | |||
4720 | if (InitList) { | |||
4721 | // Notionally, we substitute std::initializer_list<T> for 'auto' and deduce | |||
4722 | // against that. Such deduction only succeeds if removing cv-qualifiers and | |||
4723 | // references results in std::initializer_list<T>. | |||
4724 | if (!Type.getType().getNonReferenceType()->getAs<AutoType>()) | |||
4725 | return DAR_Failed; | |||
4726 | ||||
4727 | // Resolving a core issue: a braced-init-list containing any designators is | |||
4728 | // a non-deduced context. | |||
4729 | for (Expr *E : InitList->inits()) | |||
4730 | if (isa<DesignatedInitExpr>(E)) | |||
4731 | return DAR_Failed; | |||
4732 | ||||
4733 | SourceRange DeducedFromInitRange; | |||
4734 | for (unsigned i = 0, e = InitList->getNumInits(); i < e; ++i) { | |||
4735 | Expr *Init = InitList->getInit(i); | |||
4736 | ||||
4737 | if (auto TDK = DeduceTemplateArgumentsFromCallArgument( | |||
4738 | *this, TemplateParamsSt.get(), 0, TemplArg, Init, | |||
4739 | Info, Deduced, OriginalCallArgs, /*Decomposed*/ true, | |||
4740 | /*ArgIdx*/ 0, /*TDF*/ 0)) | |||
4741 | return DeductionFailed(TDK, {DeducedFromInitRange, | |||
4742 | Init->getSourceRange()}); | |||
4743 | ||||
4744 | if (DeducedFromInitRange.isInvalid() && | |||
4745 | Deduced[0].getKind() != TemplateArgument::Null) | |||
4746 | DeducedFromInitRange = Init->getSourceRange(); | |||
4747 | } | |||
4748 | } else { | |||
4749 | if (!getLangOpts().CPlusPlus && Init->refersToBitField()) { | |||
4750 | Diag(Loc, diag::err_auto_bitfield); | |||
4751 | return DAR_FailedAlreadyDiagnosed; | |||
4752 | } | |||
4753 | ||||
4754 | if (auto TDK = DeduceTemplateArgumentsFromCallArgument( | |||
4755 | *this, TemplateParamsSt.get(), 0, FuncParam, Init, Info, Deduced, | |||
4756 | OriginalCallArgs, /*Decomposed*/ false, /*ArgIdx*/ 0, /*TDF*/ 0)) | |||
4757 | return DeductionFailed(TDK, {}); | |||
4758 | } | |||
4759 | ||||
4760 | // Could be null if somehow 'auto' appears in a non-deduced context. | |||
4761 | if (Deduced[0].getKind() != TemplateArgument::Type) | |||
4762 | return DeductionFailed(TDK_Incomplete, {}); | |||
4763 | ||||
4764 | QualType DeducedType = Deduced[0].getAsType(); | |||
4765 | ||||
4766 | if (InitList) { | |||
4767 | DeducedType = BuildStdInitializerList(DeducedType, Loc); | |||
4768 | if (DeducedType.isNull()) | |||
4769 | return DAR_FailedAlreadyDiagnosed; | |||
4770 | } | |||
4771 | ||||
4772 | QualType MaybeAuto = Type.getType().getNonReferenceType(); | |||
4773 | while (MaybeAuto->isPointerType()) | |||
4774 | MaybeAuto = MaybeAuto->getPointeeType(); | |||
4775 | if (const auto *AT = MaybeAuto->getAs<AutoType>()) { | |||
4776 | if (AT->isConstrained() && !IgnoreConstraints) { | |||
4777 | auto ConstraintsResult = CheckDeducedPlaceholderConstraints( | |||
4778 | *this, *AT, Type.getContainedAutoTypeLoc(), DeducedType); | |||
4779 | if (ConstraintsResult != DAR_Succeeded) | |||
4780 | return ConstraintsResult; | |||
4781 | } | |||
4782 | } | |||
4783 | ||||
4784 | Result = SubstituteDeducedTypeTransform(*this, DeducedType).Apply(Type); | |||
4785 | if (Result.isNull()) | |||
4786 | return DAR_FailedAlreadyDiagnosed; | |||
4787 | ||||
4788 | // Check that the deduced argument type is compatible with the original | |||
4789 | // argument type per C++ [temp.deduct.call]p4. | |||
4790 | QualType DeducedA = InitList ? Deduced[0].getAsType() : Result; | |||
4791 | for (const OriginalCallArg &OriginalArg : OriginalCallArgs) { | |||
4792 | assert((bool)InitList == OriginalArg.DecomposedParam &&(static_cast <bool> ((bool)InitList == OriginalArg.DecomposedParam && "decomposed non-init-list in auto deduction?") ? void (0) : __assert_fail ("(bool)InitList == OriginalArg.DecomposedParam && \"decomposed non-init-list in auto deduction?\"" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 4793, __extension__ __PRETTY_FUNCTION__)) | |||
4793 | "decomposed non-init-list in auto deduction?")(static_cast <bool> ((bool)InitList == OriginalArg.DecomposedParam && "decomposed non-init-list in auto deduction?") ? void (0) : __assert_fail ("(bool)InitList == OriginalArg.DecomposedParam && \"decomposed non-init-list in auto deduction?\"" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 4793, __extension__ __PRETTY_FUNCTION__)); | |||
4794 | if (auto TDK = | |||
4795 | CheckOriginalCallArgDeduction(*this, Info, OriginalArg, DeducedA)) { | |||
4796 | Result = QualType(); | |||
4797 | return DeductionFailed(TDK, {}); | |||
4798 | } | |||
4799 | } | |||
4800 | ||||
4801 | return DAR_Succeeded; | |||
4802 | } | |||
4803 | ||||
4804 | QualType Sema::SubstAutoType(QualType TypeWithAuto, | |||
4805 | QualType TypeToReplaceAuto) { | |||
4806 | assert(TypeToReplaceAuto != Context.DependentTy)(static_cast <bool> (TypeToReplaceAuto != Context.DependentTy ) ? void (0) : __assert_fail ("TypeToReplaceAuto != Context.DependentTy" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 4806, __extension__ __PRETTY_FUNCTION__)); | |||
4807 | return SubstituteDeducedTypeTransform(*this, TypeToReplaceAuto) | |||
4808 | .TransformType(TypeWithAuto); | |||
4809 | } | |||
4810 | ||||
4811 | TypeSourceInfo *Sema::SubstAutoTypeSourceInfo(TypeSourceInfo *TypeWithAuto, | |||
4812 | QualType TypeToReplaceAuto) { | |||
4813 | assert(TypeToReplaceAuto != Context.DependentTy)(static_cast <bool> (TypeToReplaceAuto != Context.DependentTy ) ? void (0) : __assert_fail ("TypeToReplaceAuto != Context.DependentTy" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 4813, __extension__ __PRETTY_FUNCTION__)); | |||
4814 | return SubstituteDeducedTypeTransform(*this, TypeToReplaceAuto) | |||
4815 | .TransformType(TypeWithAuto); | |||
4816 | } | |||
4817 | ||||
4818 | QualType Sema::SubstAutoTypeDependent(QualType TypeWithAuto) { | |||
4819 | return SubstituteDeducedTypeTransform(*this, DependentAuto{false}) | |||
4820 | .TransformType(TypeWithAuto); | |||
4821 | } | |||
4822 | ||||
4823 | TypeSourceInfo * | |||
4824 | Sema::SubstAutoTypeSourceInfoDependent(TypeSourceInfo *TypeWithAuto) { | |||
4825 | return SubstituteDeducedTypeTransform(*this, DependentAuto{false}) | |||
4826 | .TransformType(TypeWithAuto); | |||
4827 | } | |||
4828 | ||||
4829 | QualType Sema::ReplaceAutoType(QualType TypeWithAuto, | |||
4830 | QualType TypeToReplaceAuto) { | |||
4831 | return SubstituteDeducedTypeTransform(*this, TypeToReplaceAuto, | |||
4832 | /*UseTypeSugar*/ false) | |||
4833 | .TransformType(TypeWithAuto); | |||
4834 | } | |||
4835 | ||||
4836 | TypeSourceInfo *Sema::ReplaceAutoTypeSourceInfo(TypeSourceInfo *TypeWithAuto, | |||
4837 | QualType TypeToReplaceAuto) { | |||
4838 | return SubstituteDeducedTypeTransform(*this, TypeToReplaceAuto, | |||
4839 | /*UseTypeSugar*/ false) | |||
4840 | .TransformType(TypeWithAuto); | |||
4841 | } | |||
4842 | ||||
4843 | void Sema::DiagnoseAutoDeductionFailure(VarDecl *VDecl, Expr *Init) { | |||
4844 | if (isa<InitListExpr>(Init)) | |||
4845 | Diag(VDecl->getLocation(), | |||
4846 | VDecl->isInitCapture() | |||
4847 | ? diag::err_init_capture_deduction_failure_from_init_list | |||
4848 | : diag::err_auto_var_deduction_failure_from_init_list) | |||
4849 | << VDecl->getDeclName() << VDecl->getType() << Init->getSourceRange(); | |||
4850 | else | |||
4851 | Diag(VDecl->getLocation(), | |||
4852 | VDecl->isInitCapture() ? diag::err_init_capture_deduction_failure | |||
4853 | : diag::err_auto_var_deduction_failure) | |||
4854 | << VDecl->getDeclName() << VDecl->getType() << Init->getType() | |||
4855 | << Init->getSourceRange(); | |||
4856 | } | |||
4857 | ||||
4858 | bool Sema::DeduceReturnType(FunctionDecl *FD, SourceLocation Loc, | |||
4859 | bool Diagnose) { | |||
4860 | assert(FD->getReturnType()->isUndeducedType())(static_cast <bool> (FD->getReturnType()->isUndeducedType ()) ? void (0) : __assert_fail ("FD->getReturnType()->isUndeducedType()" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 4860, __extension__ __PRETTY_FUNCTION__)); | |||
4861 | ||||
4862 | // For a lambda's conversion operator, deduce any 'auto' or 'decltype(auto)' | |||
4863 | // within the return type from the call operator's type. | |||
4864 | if (isLambdaConversionOperator(FD)) { | |||
4865 | CXXRecordDecl *Lambda = cast<CXXMethodDecl>(FD)->getParent(); | |||
4866 | FunctionDecl *CallOp = Lambda->getLambdaCallOperator(); | |||
4867 | ||||
4868 | // For a generic lambda, instantiate the call operator if needed. | |||
4869 | if (auto *Args = FD->getTemplateSpecializationArgs()) { | |||
4870 | CallOp = InstantiateFunctionDeclaration( | |||
4871 | CallOp->getDescribedFunctionTemplate(), Args, Loc); | |||
4872 | if (!CallOp || CallOp->isInvalidDecl()) | |||
4873 | return true; | |||
4874 | ||||
4875 | // We might need to deduce the return type by instantiating the definition | |||
4876 | // of the operator() function. | |||
4877 | if (CallOp->getReturnType()->isUndeducedType()) { | |||
4878 | runWithSufficientStackSpace(Loc, [&] { | |||
4879 | InstantiateFunctionDefinition(Loc, CallOp); | |||
4880 | }); | |||
4881 | } | |||
4882 | } | |||
4883 | ||||
4884 | if (CallOp->isInvalidDecl()) | |||
4885 | return true; | |||
4886 | assert(!CallOp->getReturnType()->isUndeducedType() &&(static_cast <bool> (!CallOp->getReturnType()->isUndeducedType () && "failed to deduce lambda return type") ? void ( 0) : __assert_fail ("!CallOp->getReturnType()->isUndeducedType() && \"failed to deduce lambda return type\"" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 4887, __extension__ __PRETTY_FUNCTION__)) | |||
4887 | "failed to deduce lambda return type")(static_cast <bool> (!CallOp->getReturnType()->isUndeducedType () && "failed to deduce lambda return type") ? void ( 0) : __assert_fail ("!CallOp->getReturnType()->isUndeducedType() && \"failed to deduce lambda return type\"" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 4887, __extension__ __PRETTY_FUNCTION__)); | |||
4888 | ||||
4889 | // Build the new return type from scratch. | |||
4890 | CallingConv RetTyCC = FD->getReturnType() | |||
4891 | ->getPointeeType() | |||
4892 | ->castAs<FunctionType>() | |||
4893 | ->getCallConv(); | |||
4894 | QualType RetType = getLambdaConversionFunctionResultType( | |||
4895 | CallOp->getType()->castAs<FunctionProtoType>(), RetTyCC); | |||
4896 | if (FD->getReturnType()->getAs<PointerType>()) | |||
4897 | RetType = Context.getPointerType(RetType); | |||
4898 | else { | |||
4899 | assert(FD->getReturnType()->getAs<BlockPointerType>())(static_cast <bool> (FD->getReturnType()->getAs< BlockPointerType>()) ? void (0) : __assert_fail ("FD->getReturnType()->getAs<BlockPointerType>()" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 4899, __extension__ __PRETTY_FUNCTION__)); | |||
4900 | RetType = Context.getBlockPointerType(RetType); | |||
4901 | } | |||
4902 | Context.adjustDeducedFunctionResultType(FD, RetType); | |||
4903 | return false; | |||
4904 | } | |||
4905 | ||||
4906 | if (FD->getTemplateInstantiationPattern()) { | |||
4907 | runWithSufficientStackSpace(Loc, [&] { | |||
4908 | InstantiateFunctionDefinition(Loc, FD); | |||
4909 | }); | |||
4910 | } | |||
4911 | ||||
4912 | bool StillUndeduced = FD->getReturnType()->isUndeducedType(); | |||
4913 | if (StillUndeduced && Diagnose && !FD->isInvalidDecl()) { | |||
4914 | Diag(Loc, diag::err_auto_fn_used_before_defined) << FD; | |||
4915 | Diag(FD->getLocation(), diag::note_callee_decl) << FD; | |||
4916 | } | |||
4917 | ||||
4918 | return StillUndeduced; | |||
4919 | } | |||
4920 | ||||
4921 | /// If this is a non-static member function, | |||
4922 | static void | |||
4923 | AddImplicitObjectParameterType(ASTContext &Context, | |||
4924 | CXXMethodDecl *Method, | |||
4925 | SmallVectorImpl<QualType> &ArgTypes) { | |||
4926 | // C++11 [temp.func.order]p3: | |||
4927 | // [...] The new parameter is of type "reference to cv A," where cv are | |||
4928 | // the cv-qualifiers of the function template (if any) and A is | |||
4929 | // the class of which the function template is a member. | |||
4930 | // | |||
4931 | // The standard doesn't say explicitly, but we pick the appropriate kind of | |||
4932 | // reference type based on [over.match.funcs]p4. | |||
4933 | QualType ArgTy = Context.getTypeDeclType(Method->getParent()); | |||
4934 | ArgTy = Context.getQualifiedType(ArgTy, Method->getMethodQualifiers()); | |||
4935 | if (Method->getRefQualifier() == RQ_RValue) | |||
4936 | ArgTy = Context.getRValueReferenceType(ArgTy); | |||
4937 | else | |||
4938 | ArgTy = Context.getLValueReferenceType(ArgTy); | |||
4939 | ArgTypes.push_back(ArgTy); | |||
4940 | } | |||
4941 | ||||
4942 | /// Determine whether the function template \p FT1 is at least as | |||
4943 | /// specialized as \p FT2. | |||
4944 | static bool isAtLeastAsSpecializedAs(Sema &S, | |||
4945 | SourceLocation Loc, | |||
4946 | FunctionTemplateDecl *FT1, | |||
4947 | FunctionTemplateDecl *FT2, | |||
4948 | TemplatePartialOrderingContext TPOC, | |||
4949 | unsigned NumCallArguments1, | |||
4950 | bool Reversed) { | |||
4951 | assert(!Reversed || TPOC == TPOC_Call)(static_cast <bool> (!Reversed || TPOC == TPOC_Call) ? void (0) : __assert_fail ("!Reversed || TPOC == TPOC_Call", "clang/lib/Sema/SemaTemplateDeduction.cpp" , 4951, __extension__ __PRETTY_FUNCTION__)); | |||
4952 | ||||
4953 | FunctionDecl *FD1 = FT1->getTemplatedDecl(); | |||
4954 | FunctionDecl *FD2 = FT2->getTemplatedDecl(); | |||
4955 | const FunctionProtoType *Proto1 = FD1->getType()->getAs<FunctionProtoType>(); | |||
4956 | const FunctionProtoType *Proto2 = FD2->getType()->getAs<FunctionProtoType>(); | |||
4957 | ||||
4958 | assert(Proto1 && Proto2 && "Function templates must have prototypes")(static_cast <bool> (Proto1 && Proto2 && "Function templates must have prototypes") ? void (0) : __assert_fail ("Proto1 && Proto2 && \"Function templates must have prototypes\"" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 4958, __extension__ __PRETTY_FUNCTION__)); | |||
4959 | TemplateParameterList *TemplateParams = FT2->getTemplateParameters(); | |||
4960 | SmallVector<DeducedTemplateArgument, 4> Deduced; | |||
4961 | Deduced.resize(TemplateParams->size()); | |||
4962 | ||||
4963 | // C++0x [temp.deduct.partial]p3: | |||
4964 | // The types used to determine the ordering depend on the context in which | |||
4965 | // the partial ordering is done: | |||
4966 | TemplateDeductionInfo Info(Loc); | |||
4967 | SmallVector<QualType, 4> Args2; | |||
4968 | switch (TPOC) { | |||
4969 | case TPOC_Call: { | |||
4970 | // - In the context of a function call, the function parameter types are | |||
4971 | // used. | |||
4972 | CXXMethodDecl *Method1 = dyn_cast<CXXMethodDecl>(FD1); | |||
4973 | CXXMethodDecl *Method2 = dyn_cast<CXXMethodDecl>(FD2); | |||
4974 | ||||
4975 | // C++11 [temp.func.order]p3: | |||
4976 | // [...] If only one of the function templates is a non-static | |||
4977 | // member, that function template is considered to have a new | |||
4978 | // first parameter inserted in its function parameter list. The | |||
4979 | // new parameter is of type "reference to cv A," where cv are | |||
4980 | // the cv-qualifiers of the function template (if any) and A is | |||
4981 | // the class of which the function template is a member. | |||
4982 | // | |||
4983 | // Note that we interpret this to mean "if one of the function | |||
4984 | // templates is a non-static member and the other is a non-member"; | |||
4985 | // otherwise, the ordering rules for static functions against non-static | |||
4986 | // functions don't make any sense. | |||
4987 | // | |||
4988 | // C++98/03 doesn't have this provision but we've extended DR532 to cover | |||
4989 | // it as wording was broken prior to it. | |||
4990 | SmallVector<QualType, 4> Args1; | |||
4991 | ||||
4992 | unsigned NumComparedArguments = NumCallArguments1; | |||
4993 | ||||
4994 | if (!Method2 && Method1 && !Method1->isStatic()) { | |||
4995 | // Compare 'this' from Method1 against first parameter from Method2. | |||
4996 | AddImplicitObjectParameterType(S.Context, Method1, Args1); | |||
4997 | ++NumComparedArguments; | |||
4998 | } else if (!Method1 && Method2 && !Method2->isStatic()) { | |||
4999 | // Compare 'this' from Method2 against first parameter from Method1. | |||
5000 | AddImplicitObjectParameterType(S.Context, Method2, Args2); | |||
5001 | } else if (Method1 && Method2 && Reversed) { | |||
5002 | // Compare 'this' from Method1 against second parameter from Method2 | |||
5003 | // and 'this' from Method2 against second parameter from Method1. | |||
5004 | AddImplicitObjectParameterType(S.Context, Method1, Args1); | |||
5005 | AddImplicitObjectParameterType(S.Context, Method2, Args2); | |||
5006 | ++NumComparedArguments; | |||
5007 | } | |||
5008 | ||||
5009 | Args1.insert(Args1.end(), Proto1->param_type_begin(), | |||
5010 | Proto1->param_type_end()); | |||
5011 | Args2.insert(Args2.end(), Proto2->param_type_begin(), | |||
5012 | Proto2->param_type_end()); | |||
5013 | ||||
5014 | // C++ [temp.func.order]p5: | |||
5015 | // The presence of unused ellipsis and default arguments has no effect on | |||
5016 | // the partial ordering of function templates. | |||
5017 | if (Args1.size() > NumComparedArguments) | |||
5018 | Args1.resize(NumComparedArguments); | |||
5019 | if (Args2.size() > NumComparedArguments) | |||
5020 | Args2.resize(NumComparedArguments); | |||
5021 | if (Reversed) | |||
5022 | std::reverse(Args2.begin(), Args2.end()); | |||
5023 | ||||
5024 | if (DeduceTemplateArguments(S, TemplateParams, Args2.data(), Args2.size(), | |||
5025 | Args1.data(), Args1.size(), Info, Deduced, | |||
5026 | TDF_None, /*PartialOrdering=*/true)) | |||
5027 | return false; | |||
5028 | ||||
5029 | break; | |||
5030 | } | |||
5031 | ||||
5032 | case TPOC_Conversion: | |||
5033 | // - In the context of a call to a conversion operator, the return types | |||
5034 | // of the conversion function templates are used. | |||
5035 | if (DeduceTemplateArgumentsByTypeMatch( | |||
5036 | S, TemplateParams, Proto2->getReturnType(), Proto1->getReturnType(), | |||
5037 | Info, Deduced, TDF_None, | |||
5038 | /*PartialOrdering=*/true)) | |||
5039 | return false; | |||
5040 | break; | |||
5041 | ||||
5042 | case TPOC_Other: | |||
5043 | // - In other contexts (14.6.6.2) the function template's function type | |||
5044 | // is used. | |||
5045 | if (DeduceTemplateArgumentsByTypeMatch(S, TemplateParams, | |||
5046 | FD2->getType(), FD1->getType(), | |||
5047 | Info, Deduced, TDF_None, | |||
5048 | /*PartialOrdering=*/true)) | |||
5049 | return false; | |||
5050 | break; | |||
5051 | } | |||
5052 | ||||
5053 | // C++0x [temp.deduct.partial]p11: | |||
5054 | // In most cases, all template parameters must have values in order for | |||
5055 | // deduction to succeed, but for partial ordering purposes a template | |||
5056 | // parameter may remain without a value provided it is not used in the | |||
5057 | // types being used for partial ordering. [ Note: a template parameter used | |||
5058 | // in a non-deduced context is considered used. -end note] | |||
5059 | unsigned ArgIdx = 0, NumArgs = Deduced.size(); | |||
5060 | for (; ArgIdx != NumArgs; ++ArgIdx) | |||
5061 | if (Deduced[ArgIdx].isNull()) | |||
5062 | break; | |||
5063 | ||||
5064 | // FIXME: We fail to implement [temp.deduct.type]p1 along this path. We need | |||
5065 | // to substitute the deduced arguments back into the template and check that | |||
5066 | // we get the right type. | |||
5067 | ||||
5068 | if (ArgIdx == NumArgs) { | |||
5069 | // All template arguments were deduced. FT1 is at least as specialized | |||
5070 | // as FT2. | |||
5071 | return true; | |||
5072 | } | |||
5073 | ||||
5074 | // Figure out which template parameters were used. | |||
5075 | llvm::SmallBitVector UsedParameters(TemplateParams->size()); | |||
5076 | switch (TPOC) { | |||
5077 | case TPOC_Call: | |||
5078 | for (unsigned I = 0, N = Args2.size(); I != N; ++I) | |||
5079 | ::MarkUsedTemplateParameters(S.Context, Args2[I], false, | |||
5080 | TemplateParams->getDepth(), | |||
5081 | UsedParameters); | |||
5082 | break; | |||
5083 | ||||
5084 | case TPOC_Conversion: | |||
5085 | ::MarkUsedTemplateParameters(S.Context, Proto2->getReturnType(), false, | |||
5086 | TemplateParams->getDepth(), UsedParameters); | |||
5087 | break; | |||
5088 | ||||
5089 | case TPOC_Other: | |||
5090 | ::MarkUsedTemplateParameters(S.Context, FD2->getType(), false, | |||
5091 | TemplateParams->getDepth(), | |||
5092 | UsedParameters); | |||
5093 | break; | |||
5094 | } | |||
5095 | ||||
5096 | for (; ArgIdx != NumArgs; ++ArgIdx) | |||
5097 | // If this argument had no value deduced but was used in one of the types | |||
5098 | // used for partial ordering, then deduction fails. | |||
5099 | if (Deduced[ArgIdx].isNull() && UsedParameters[ArgIdx]) | |||
5100 | return false; | |||
5101 | ||||
5102 | return true; | |||
5103 | } | |||
5104 | ||||
5105 | /// Determine whether this a function template whose parameter-type-list | |||
5106 | /// ends with a function parameter pack. | |||
5107 | static bool isVariadicFunctionTemplate(FunctionTemplateDecl *FunTmpl) { | |||
5108 | FunctionDecl *Function = FunTmpl->getTemplatedDecl(); | |||
5109 | unsigned NumParams = Function->getNumParams(); | |||
5110 | if (NumParams == 0) | |||
5111 | return false; | |||
5112 | ||||
5113 | ParmVarDecl *Last = Function->getParamDecl(NumParams - 1); | |||
5114 | if (!Last->isParameterPack()) | |||
5115 | return false; | |||
5116 | ||||
5117 | // Make sure that no previous parameter is a parameter pack. | |||
5118 | while (--NumParams > 0) { | |||
5119 | if (Function->getParamDecl(NumParams - 1)->isParameterPack()) | |||
5120 | return false; | |||
5121 | } | |||
5122 | ||||
5123 | return true; | |||
5124 | } | |||
5125 | ||||
5126 | /// Returns the more specialized function template according | |||
5127 | /// to the rules of function template partial ordering (C++ [temp.func.order]). | |||
5128 | /// | |||
5129 | /// \param FT1 the first function template | |||
5130 | /// | |||
5131 | /// \param FT2 the second function template | |||
5132 | /// | |||
5133 | /// \param TPOC the context in which we are performing partial ordering of | |||
5134 | /// function templates. | |||
5135 | /// | |||
5136 | /// \param NumCallArguments1 The number of arguments in the call to FT1, used | |||
5137 | /// only when \c TPOC is \c TPOC_Call. | |||
5138 | /// | |||
5139 | /// \param NumCallArguments2 The number of arguments in the call to FT2, used | |||
5140 | /// only when \c TPOC is \c TPOC_Call. | |||
5141 | /// | |||
5142 | /// \param Reversed If \c true, exactly one of FT1 and FT2 is an overload | |||
5143 | /// candidate with a reversed parameter order. In this case, the corresponding | |||
5144 | /// P/A pairs between FT1 and FT2 are reversed. | |||
5145 | /// | |||
5146 | /// \returns the more specialized function template. If neither | |||
5147 | /// template is more specialized, returns NULL. | |||
5148 | FunctionTemplateDecl * | |||
5149 | Sema::getMoreSpecializedTemplate(FunctionTemplateDecl *FT1, | |||
5150 | FunctionTemplateDecl *FT2, | |||
5151 | SourceLocation Loc, | |||
5152 | TemplatePartialOrderingContext TPOC, | |||
5153 | unsigned NumCallArguments1, | |||
5154 | unsigned NumCallArguments2, | |||
5155 | bool Reversed) { | |||
5156 | ||||
5157 | auto JudgeByConstraints = [&] () -> FunctionTemplateDecl * { | |||
5158 | llvm::SmallVector<const Expr *, 3> AC1, AC2; | |||
5159 | FT1->getAssociatedConstraints(AC1); | |||
5160 | FT2->getAssociatedConstraints(AC2); | |||
5161 | bool AtLeastAsConstrained1, AtLeastAsConstrained2; | |||
5162 | if (IsAtLeastAsConstrained(FT1, AC1, FT2, AC2, AtLeastAsConstrained1)) | |||
5163 | return nullptr; | |||
5164 | if (IsAtLeastAsConstrained(FT2, AC2, FT1, AC1, AtLeastAsConstrained2)) | |||
5165 | return nullptr; | |||
5166 | if (AtLeastAsConstrained1 == AtLeastAsConstrained2) | |||
5167 | return nullptr; | |||
5168 | return AtLeastAsConstrained1 ? FT1 : FT2; | |||
5169 | }; | |||
5170 | ||||
5171 | bool Better1 = isAtLeastAsSpecializedAs(*this, Loc, FT1, FT2, TPOC, | |||
5172 | NumCallArguments1, Reversed); | |||
5173 | bool Better2 = isAtLeastAsSpecializedAs(*this, Loc, FT2, FT1, TPOC, | |||
5174 | NumCallArguments2, Reversed); | |||
5175 | ||||
5176 | if (Better1 != Better2) // We have a clear winner | |||
5177 | return Better1 ? FT1 : FT2; | |||
5178 | ||||
5179 | if (!Better1 && !Better2) // Neither is better than the other | |||
5180 | return JudgeByConstraints(); | |||
5181 | ||||
5182 | // FIXME: This mimics what GCC implements, but doesn't match up with the | |||
5183 | // proposed resolution for core issue 692. This area needs to be sorted out, | |||
5184 | // but for now we attempt to maintain compatibility. | |||
5185 | bool Variadic1 = isVariadicFunctionTemplate(FT1); | |||
5186 | bool Variadic2 = isVariadicFunctionTemplate(FT2); | |||
5187 | if (Variadic1 != Variadic2) | |||
5188 | return Variadic1? FT2 : FT1; | |||
5189 | ||||
5190 | return JudgeByConstraints(); | |||
5191 | } | |||
5192 | ||||
5193 | /// Determine if the two templates are equivalent. | |||
5194 | static bool isSameTemplate(TemplateDecl *T1, TemplateDecl *T2) { | |||
5195 | if (T1 == T2) | |||
5196 | return true; | |||
5197 | ||||
5198 | if (!T1 || !T2) | |||
5199 | return false; | |||
5200 | ||||
5201 | return T1->getCanonicalDecl() == T2->getCanonicalDecl(); | |||
5202 | } | |||
5203 | ||||
5204 | /// Retrieve the most specialized of the given function template | |||
5205 | /// specializations. | |||
5206 | /// | |||
5207 | /// \param SpecBegin the start iterator of the function template | |||
5208 | /// specializations that we will be comparing. | |||
5209 | /// | |||
5210 | /// \param SpecEnd the end iterator of the function template | |||
5211 | /// specializations, paired with \p SpecBegin. | |||
5212 | /// | |||
5213 | /// \param Loc the location where the ambiguity or no-specializations | |||
5214 | /// diagnostic should occur. | |||
5215 | /// | |||
5216 | /// \param NoneDiag partial diagnostic used to diagnose cases where there are | |||
5217 | /// no matching candidates. | |||
5218 | /// | |||
5219 | /// \param AmbigDiag partial diagnostic used to diagnose an ambiguity, if one | |||
5220 | /// occurs. | |||
5221 | /// | |||
5222 | /// \param CandidateDiag partial diagnostic used for each function template | |||
5223 | /// specialization that is a candidate in the ambiguous ordering. One parameter | |||
5224 | /// in this diagnostic should be unbound, which will correspond to the string | |||
5225 | /// describing the template arguments for the function template specialization. | |||
5226 | /// | |||
5227 | /// \returns the most specialized function template specialization, if | |||
5228 | /// found. Otherwise, returns SpecEnd. | |||
5229 | UnresolvedSetIterator Sema::getMostSpecialized( | |||
5230 | UnresolvedSetIterator SpecBegin, UnresolvedSetIterator SpecEnd, | |||
5231 | TemplateSpecCandidateSet &FailedCandidates, | |||
5232 | SourceLocation Loc, const PartialDiagnostic &NoneDiag, | |||
5233 | const PartialDiagnostic &AmbigDiag, const PartialDiagnostic &CandidateDiag, | |||
5234 | bool Complain, QualType TargetType) { | |||
5235 | if (SpecBegin == SpecEnd) { | |||
5236 | if (Complain) { | |||
5237 | Diag(Loc, NoneDiag); | |||
5238 | FailedCandidates.NoteCandidates(*this, Loc); | |||
5239 | } | |||
5240 | return SpecEnd; | |||
5241 | } | |||
5242 | ||||
5243 | if (SpecBegin + 1 == SpecEnd) | |||
5244 | return SpecBegin; | |||
5245 | ||||
5246 | // Find the function template that is better than all of the templates it | |||
5247 | // has been compared to. | |||
5248 | UnresolvedSetIterator Best = SpecBegin; | |||
5249 | FunctionTemplateDecl *BestTemplate | |||
5250 | = cast<FunctionDecl>(*Best)->getPrimaryTemplate(); | |||
5251 | assert(BestTemplate && "Not a function template specialization?")(static_cast <bool> (BestTemplate && "Not a function template specialization?" ) ? void (0) : __assert_fail ("BestTemplate && \"Not a function template specialization?\"" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 5251, __extension__ __PRETTY_FUNCTION__)); | |||
5252 | for (UnresolvedSetIterator I = SpecBegin + 1; I != SpecEnd; ++I) { | |||
5253 | FunctionTemplateDecl *Challenger | |||
5254 | = cast<FunctionDecl>(*I)->getPrimaryTemplate(); | |||
5255 | assert(Challenger && "Not a function template specialization?")(static_cast <bool> (Challenger && "Not a function template specialization?" ) ? void (0) : __assert_fail ("Challenger && \"Not a function template specialization?\"" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 5255, __extension__ __PRETTY_FUNCTION__)); | |||
5256 | if (isSameTemplate(getMoreSpecializedTemplate(BestTemplate, Challenger, | |||
5257 | Loc, TPOC_Other, 0, 0), | |||
5258 | Challenger)) { | |||
5259 | Best = I; | |||
5260 | BestTemplate = Challenger; | |||
5261 | } | |||
5262 | } | |||
5263 | ||||
5264 | // Make sure that the "best" function template is more specialized than all | |||
5265 | // of the others. | |||
5266 | bool Ambiguous = false; | |||
5267 | for (UnresolvedSetIterator I = SpecBegin; I != SpecEnd; ++I) { | |||
5268 | FunctionTemplateDecl *Challenger | |||
5269 | = cast<FunctionDecl>(*I)->getPrimaryTemplate(); | |||
5270 | if (I != Best && | |||
5271 | !isSameTemplate(getMoreSpecializedTemplate(BestTemplate, Challenger, | |||
5272 | Loc, TPOC_Other, 0, 0), | |||
5273 | BestTemplate)) { | |||
5274 | Ambiguous = true; | |||
5275 | break; | |||
5276 | } | |||
5277 | } | |||
5278 | ||||
5279 | if (!Ambiguous) { | |||
5280 | // We found an answer. Return it. | |||
5281 | return Best; | |||
5282 | } | |||
5283 | ||||
5284 | // Diagnose the ambiguity. | |||
5285 | if (Complain) { | |||
5286 | Diag(Loc, AmbigDiag); | |||
5287 | ||||
5288 | // FIXME: Can we order the candidates in some sane way? | |||
5289 | for (UnresolvedSetIterator I = SpecBegin; I != SpecEnd; ++I) { | |||
5290 | PartialDiagnostic PD = CandidateDiag; | |||
5291 | const auto *FD = cast<FunctionDecl>(*I); | |||
5292 | PD << FD << getTemplateArgumentBindingsText( | |||
5293 | FD->getPrimaryTemplate()->getTemplateParameters(), | |||
5294 | *FD->getTemplateSpecializationArgs()); | |||
5295 | if (!TargetType.isNull()) | |||
5296 | HandleFunctionTypeMismatch(PD, FD->getType(), TargetType); | |||
5297 | Diag((*I)->getLocation(), PD); | |||
5298 | } | |||
5299 | } | |||
5300 | ||||
5301 | return SpecEnd; | |||
5302 | } | |||
5303 | ||||
5304 | /// Determine whether one partial specialization, P1, is at least as | |||
5305 | /// specialized than another, P2. | |||
5306 | /// | |||
5307 | /// \tparam TemplateLikeDecl The kind of P2, which must be a | |||
5308 | /// TemplateDecl or {Class,Var}TemplatePartialSpecializationDecl. | |||
5309 | /// \param T1 The injected-class-name of P1 (faked for a variable template). | |||
5310 | /// \param T2 The injected-class-name of P2 (faked for a variable template). | |||
5311 | template<typename TemplateLikeDecl> | |||
5312 | static bool isAtLeastAsSpecializedAs(Sema &S, QualType T1, QualType T2, | |||
5313 | TemplateLikeDecl *P2, | |||
5314 | TemplateDeductionInfo &Info) { | |||
5315 | // C++ [temp.class.order]p1: | |||
5316 | // For two class template partial specializations, the first is at least as | |||
5317 | // specialized as the second if, given the following rewrite to two | |||
5318 | // function templates, the first function template is at least as | |||
5319 | // specialized as the second according to the ordering rules for function | |||
5320 | // templates (14.6.6.2): | |||
5321 | // - the first function template has the same template parameters as the | |||
5322 | // first partial specialization and has a single function parameter | |||
5323 | // whose type is a class template specialization with the template | |||
5324 | // arguments of the first partial specialization, and | |||
5325 | // - the second function template has the same template parameters as the | |||
5326 | // second partial specialization and has a single function parameter | |||
5327 | // whose type is a class template specialization with the template | |||
5328 | // arguments of the second partial specialization. | |||
5329 | // | |||
5330 | // Rather than synthesize function templates, we merely perform the | |||
5331 | // equivalent partial ordering by performing deduction directly on | |||
5332 | // the template arguments of the class template partial | |||
5333 | // specializations. This computation is slightly simpler than the | |||
5334 | // general problem of function template partial ordering, because | |||
5335 | // class template partial specializations are more constrained. We | |||
5336 | // know that every template parameter is deducible from the class | |||
5337 | // template partial specialization's template arguments, for | |||
5338 | // example. | |||
5339 | SmallVector<DeducedTemplateArgument, 4> Deduced; | |||
5340 | ||||
5341 | // Determine whether P1 is at least as specialized as P2. | |||
5342 | Deduced.resize(P2->getTemplateParameters()->size()); | |||
5343 | if (DeduceTemplateArgumentsByTypeMatch(S, P2->getTemplateParameters(), | |||
5344 | T2, T1, Info, Deduced, TDF_None, | |||
5345 | /*PartialOrdering=*/true)) | |||
5346 | return false; | |||
5347 | ||||
5348 | SmallVector<TemplateArgument, 4> DeducedArgs(Deduced.begin(), | |||
5349 | Deduced.end()); | |||
5350 | Sema::InstantiatingTemplate Inst(S, Info.getLocation(), P2, DeducedArgs, | |||
5351 | Info); | |||
5352 | if (Inst.isInvalid()) | |||
5353 | return false; | |||
5354 | ||||
5355 | auto *TST1 = T1->castAs<TemplateSpecializationType>(); | |||
5356 | bool AtLeastAsSpecialized; | |||
5357 | S.runWithSufficientStackSpace(Info.getLocation(), [&] { | |||
5358 | AtLeastAsSpecialized = !FinishTemplateArgumentDeduction( | |||
5359 | S, P2, /*IsPartialOrdering=*/true, | |||
5360 | TemplateArgumentList(TemplateArgumentList::OnStack, | |||
5361 | TST1->template_arguments()), | |||
5362 | Deduced, Info); | |||
5363 | }); | |||
5364 | return AtLeastAsSpecialized; | |||
5365 | } | |||
5366 | ||||
5367 | /// Returns the more specialized class template partial specialization | |||
5368 | /// according to the rules of partial ordering of class template partial | |||
5369 | /// specializations (C++ [temp.class.order]). | |||
5370 | /// | |||
5371 | /// \param PS1 the first class template partial specialization | |||
5372 | /// | |||
5373 | /// \param PS2 the second class template partial specialization | |||
5374 | /// | |||
5375 | /// \returns the more specialized class template partial specialization. If | |||
5376 | /// neither partial specialization is more specialized, returns NULL. | |||
5377 | ClassTemplatePartialSpecializationDecl * | |||
5378 | Sema::getMoreSpecializedPartialSpecialization( | |||
5379 | ClassTemplatePartialSpecializationDecl *PS1, | |||
5380 | ClassTemplatePartialSpecializationDecl *PS2, | |||
5381 | SourceLocation Loc) { | |||
5382 | QualType PT1 = PS1->getInjectedSpecializationType(); | |||
5383 | QualType PT2 = PS2->getInjectedSpecializationType(); | |||
5384 | ||||
5385 | TemplateDeductionInfo Info(Loc); | |||
5386 | bool Better1 = isAtLeastAsSpecializedAs(*this, PT1, PT2, PS2, Info); | |||
5387 | bool Better2 = isAtLeastAsSpecializedAs(*this, PT2, PT1, PS1, Info); | |||
5388 | ||||
5389 | if (!Better1 && !Better2) | |||
5390 | return nullptr; | |||
5391 | if (Better1 && Better2) { | |||
5392 | llvm::SmallVector<const Expr *, 3> AC1, AC2; | |||
5393 | PS1->getAssociatedConstraints(AC1); | |||
5394 | PS2->getAssociatedConstraints(AC2); | |||
5395 | bool AtLeastAsConstrained1, AtLeastAsConstrained2; | |||
5396 | if (IsAtLeastAsConstrained(PS1, AC1, PS2, AC2, AtLeastAsConstrained1)) | |||
5397 | return nullptr; | |||
5398 | if (IsAtLeastAsConstrained(PS2, AC2, PS1, AC1, AtLeastAsConstrained2)) | |||
5399 | return nullptr; | |||
5400 | if (AtLeastAsConstrained1 == AtLeastAsConstrained2) | |||
5401 | return nullptr; | |||
5402 | return AtLeastAsConstrained1 ? PS1 : PS2; | |||
5403 | } | |||
5404 | ||||
5405 | return Better1 ? PS1 : PS2; | |||
5406 | } | |||
5407 | ||||
5408 | bool Sema::isMoreSpecializedThanPrimary( | |||
5409 | ClassTemplatePartialSpecializationDecl *Spec, TemplateDeductionInfo &Info) { | |||
5410 | ClassTemplateDecl *Primary = Spec->getSpecializedTemplate(); | |||
5411 | QualType PrimaryT = Primary->getInjectedClassNameSpecialization(); | |||
5412 | QualType PartialT = Spec->getInjectedSpecializationType(); | |||
5413 | if (!isAtLeastAsSpecializedAs(*this, PartialT, PrimaryT, Primary, Info)) | |||
5414 | return false; | |||
5415 | if (!isAtLeastAsSpecializedAs(*this, PrimaryT, PartialT, Spec, Info)) | |||
5416 | return true; | |||
5417 | Info.clearSFINAEDiagnostic(); | |||
5418 | llvm::SmallVector<const Expr *, 3> PrimaryAC, SpecAC; | |||
5419 | Primary->getAssociatedConstraints(PrimaryAC); | |||
5420 | Spec->getAssociatedConstraints(SpecAC); | |||
5421 | bool AtLeastAsConstrainedPrimary, AtLeastAsConstrainedSpec; | |||
5422 | if (IsAtLeastAsConstrained(Spec, SpecAC, Primary, PrimaryAC, | |||
5423 | AtLeastAsConstrainedSpec)) | |||
5424 | return false; | |||
5425 | if (!AtLeastAsConstrainedSpec) | |||
5426 | return false; | |||
5427 | if (IsAtLeastAsConstrained(Primary, PrimaryAC, Spec, SpecAC, | |||
5428 | AtLeastAsConstrainedPrimary)) | |||
5429 | return false; | |||
5430 | return !AtLeastAsConstrainedPrimary; | |||
5431 | } | |||
5432 | ||||
5433 | VarTemplatePartialSpecializationDecl * | |||
5434 | Sema::getMoreSpecializedPartialSpecialization( | |||
5435 | VarTemplatePartialSpecializationDecl *PS1, | |||
5436 | VarTemplatePartialSpecializationDecl *PS2, SourceLocation Loc) { | |||
5437 | // Pretend the variable template specializations are class template | |||
5438 | // specializations and form a fake injected class name type for comparison. | |||
5439 | assert(PS1->getSpecializedTemplate() == PS2->getSpecializedTemplate() &&(static_cast <bool> (PS1->getSpecializedTemplate() == PS2->getSpecializedTemplate() && "the partial specializations being compared should specialize" " the same template.") ? void (0) : __assert_fail ("PS1->getSpecializedTemplate() == PS2->getSpecializedTemplate() && \"the partial specializations being compared should specialize\" \" the same template.\"" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 5441, __extension__ __PRETTY_FUNCTION__)) | |||
5440 | "the partial specializations being compared should specialize"(static_cast <bool> (PS1->getSpecializedTemplate() == PS2->getSpecializedTemplate() && "the partial specializations being compared should specialize" " the same template.") ? void (0) : __assert_fail ("PS1->getSpecializedTemplate() == PS2->getSpecializedTemplate() && \"the partial specializations being compared should specialize\" \" the same template.\"" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 5441, __extension__ __PRETTY_FUNCTION__)) | |||
5441 | " the same template.")(static_cast <bool> (PS1->getSpecializedTemplate() == PS2->getSpecializedTemplate() && "the partial specializations being compared should specialize" " the same template.") ? void (0) : __assert_fail ("PS1->getSpecializedTemplate() == PS2->getSpecializedTemplate() && \"the partial specializations being compared should specialize\" \" the same template.\"" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 5441, __extension__ __PRETTY_FUNCTION__)); | |||
5442 | TemplateName Name(PS1->getSpecializedTemplate()); | |||
5443 | TemplateName CanonTemplate = Context.getCanonicalTemplateName(Name); | |||
5444 | QualType PT1 = Context.getTemplateSpecializationType( | |||
5445 | CanonTemplate, PS1->getTemplateArgs().asArray()); | |||
5446 | QualType PT2 = Context.getTemplateSpecializationType( | |||
5447 | CanonTemplate, PS2->getTemplateArgs().asArray()); | |||
5448 | ||||
5449 | TemplateDeductionInfo Info(Loc); | |||
5450 | bool Better1 = isAtLeastAsSpecializedAs(*this, PT1, PT2, PS2, Info); | |||
5451 | bool Better2 = isAtLeastAsSpecializedAs(*this, PT2, PT1, PS1, Info); | |||
5452 | ||||
5453 | if (!Better1 && !Better2) | |||
5454 | return nullptr; | |||
5455 | if (Better1 && Better2) { | |||
5456 | llvm::SmallVector<const Expr *, 3> AC1, AC2; | |||
5457 | PS1->getAssociatedConstraints(AC1); | |||
5458 | PS2->getAssociatedConstraints(AC2); | |||
5459 | bool AtLeastAsConstrained1, AtLeastAsConstrained2; | |||
5460 | if (IsAtLeastAsConstrained(PS1, AC1, PS2, AC2, AtLeastAsConstrained1)) | |||
5461 | return nullptr; | |||
5462 | if (IsAtLeastAsConstrained(PS2, AC2, PS1, AC1, AtLeastAsConstrained2)) | |||
5463 | return nullptr; | |||
5464 | if (AtLeastAsConstrained1 == AtLeastAsConstrained2) | |||
5465 | return nullptr; | |||
5466 | return AtLeastAsConstrained1 ? PS1 : PS2; | |||
5467 | } | |||
5468 | ||||
5469 | return Better1 ? PS1 : PS2; | |||
5470 | } | |||
5471 | ||||
5472 | bool Sema::isMoreSpecializedThanPrimary( | |||
5473 | VarTemplatePartialSpecializationDecl *Spec, TemplateDeductionInfo &Info) { | |||
5474 | TemplateDecl *Primary = Spec->getSpecializedTemplate(); | |||
5475 | // FIXME: Cache the injected template arguments rather than recomputing | |||
5476 | // them for each partial specialization. | |||
5477 | SmallVector<TemplateArgument, 8> PrimaryArgs; | |||
5478 | Context.getInjectedTemplateArgs(Primary->getTemplateParameters(), | |||
5479 | PrimaryArgs); | |||
5480 | ||||
5481 | TemplateName CanonTemplate = | |||
5482 | Context.getCanonicalTemplateName(TemplateName(Primary)); | |||
5483 | QualType PrimaryT = Context.getTemplateSpecializationType( | |||
5484 | CanonTemplate, PrimaryArgs); | |||
5485 | QualType PartialT = Context.getTemplateSpecializationType( | |||
5486 | CanonTemplate, Spec->getTemplateArgs().asArray()); | |||
5487 | ||||
5488 | if (!isAtLeastAsSpecializedAs(*this, PartialT, PrimaryT, Primary, Info)) | |||
5489 | return false; | |||
5490 | if (!isAtLeastAsSpecializedAs(*this, PrimaryT, PartialT, Spec, Info)) | |||
5491 | return true; | |||
5492 | Info.clearSFINAEDiagnostic(); | |||
5493 | llvm::SmallVector<const Expr *, 3> PrimaryAC, SpecAC; | |||
5494 | Primary->getAssociatedConstraints(PrimaryAC); | |||
5495 | Spec->getAssociatedConstraints(SpecAC); | |||
5496 | bool AtLeastAsConstrainedPrimary, AtLeastAsConstrainedSpec; | |||
5497 | if (IsAtLeastAsConstrained(Spec, SpecAC, Primary, PrimaryAC, | |||
5498 | AtLeastAsConstrainedSpec)) | |||
5499 | return false; | |||
5500 | if (!AtLeastAsConstrainedSpec) | |||
5501 | return false; | |||
5502 | if (IsAtLeastAsConstrained(Primary, PrimaryAC, Spec, SpecAC, | |||
5503 | AtLeastAsConstrainedPrimary)) | |||
5504 | return false; | |||
5505 | return !AtLeastAsConstrainedPrimary; | |||
5506 | } | |||
5507 | ||||
5508 | bool Sema::isTemplateTemplateParameterAtLeastAsSpecializedAs( | |||
5509 | TemplateParameterList *P, TemplateDecl *AArg, SourceLocation Loc) { | |||
5510 | // C++1z [temp.arg.template]p4: (DR 150) | |||
5511 | // A template template-parameter P is at least as specialized as a | |||
5512 | // template template-argument A if, given the following rewrite to two | |||
5513 | // function templates... | |||
5514 | ||||
5515 | // Rather than synthesize function templates, we merely perform the | |||
5516 | // equivalent partial ordering by performing deduction directly on | |||
5517 | // the template parameter lists of the template template parameters. | |||
5518 | // | |||
5519 | // Given an invented class template X with the template parameter list of | |||
5520 | // A (including default arguments): | |||
5521 | TemplateName X = Context.getCanonicalTemplateName(TemplateName(AArg)); | |||
5522 | TemplateParameterList *A = AArg->getTemplateParameters(); | |||
5523 | ||||
5524 | // - Each function template has a single function parameter whose type is | |||
5525 | // a specialization of X with template arguments corresponding to the | |||
5526 | // template parameters from the respective function template | |||
5527 | SmallVector<TemplateArgument, 8> AArgs; | |||
5528 | Context.getInjectedTemplateArgs(A, AArgs); | |||
5529 | ||||
5530 | // Check P's arguments against A's parameter list. This will fill in default | |||
5531 | // template arguments as needed. AArgs are already correct by construction. | |||
5532 | // We can't just use CheckTemplateIdType because that will expand alias | |||
5533 | // templates. | |||
5534 | SmallVector<TemplateArgument, 4> PArgs; | |||
5535 | { | |||
5536 | SFINAETrap Trap(*this); | |||
5537 | ||||
5538 | Context.getInjectedTemplateArgs(P, PArgs); | |||
5539 | TemplateArgumentListInfo PArgList(P->getLAngleLoc(), | |||
5540 | P->getRAngleLoc()); | |||
5541 | for (unsigned I = 0, N = P->size(); I != N; ++I) { | |||
5542 | // Unwrap packs that getInjectedTemplateArgs wrapped around pack | |||
5543 | // expansions, to form an "as written" argument list. | |||
5544 | TemplateArgument Arg = PArgs[I]; | |||
5545 | if (Arg.getKind() == TemplateArgument::Pack) { | |||
5546 | assert(Arg.pack_size() == 1 && Arg.pack_begin()->isPackExpansion())(static_cast <bool> (Arg.pack_size() == 1 && Arg .pack_begin()->isPackExpansion()) ? void (0) : __assert_fail ("Arg.pack_size() == 1 && Arg.pack_begin()->isPackExpansion()" , "clang/lib/Sema/SemaTemplateDeduction.cpp", 5546, __extension__ __PRETTY_FUNCTION__)); | |||
5547 | Arg = *Arg.pack_begin(); | |||
5548 | } | |||
5549 | PArgList.addArgument(getTrivialTemplateArgumentLoc( | |||
5550 | Arg, QualType(), P->getParam(I)->getLocation())); | |||
5551 | } | |||
5552 | PArgs.clear(); | |||
5553 | ||||
5554 | // C++1z [temp.arg.template]p3: | |||
5555 | // If the rewrite produces an invalid type, then P is not at least as | |||
5556 | // specialized as A. | |||
5557 | if (CheckTemplateArgumentList(AArg, Loc, PArgList, false, PArgs) || | |||
5558 | Trap.hasErrorOccurred()) | |||
5559 | return false; | |||
5560 | } | |||
5561 | ||||
5562 | QualType AType = Context.getTemplateSpecializationType(X, AArgs); | |||
5563 | QualType PType = Context.getTemplateSpecializationType(X, PArgs); | |||
5564 | ||||
5565 | // ... the function template corresponding to P is at least as specialized | |||
5566 | // as the function template corresponding to A according to the partial | |||
5567 | // ordering rules for function templates. | |||
5568 | TemplateDeductionInfo Info(Loc, A->getDepth()); | |||
5569 | return isAtLeastAsSpecializedAs(*this, PType, AType, AArg, Info); | |||
5570 | } | |||
5571 | ||||
5572 | namespace { | |||
5573 | struct MarkUsedTemplateParameterVisitor : | |||
5574 | RecursiveASTVisitor<MarkUsedTemplateParameterVisitor> { | |||
5575 | llvm::SmallBitVector &Used; | |||
5576 | unsigned Depth; | |||
5577 | ||||
5578 | MarkUsedTemplateParameterVisitor(llvm::SmallBitVector &Used, | |||
5579 | unsigned Depth) | |||
5580 | : Used(Used), Depth(Depth) { } | |||
5581 | ||||
5582 | bool VisitTemplateTypeParmType(TemplateTypeParmType *T) { | |||
5583 | if (T->getDepth() == Depth) | |||
5584 | Used[T->getIndex()] = true; | |||
5585 | return true; | |||
5586 | } | |||
5587 | ||||
5588 | bool TraverseTemplateName(TemplateName Template) { | |||
5589 | if (auto *TTP = | |||
5590 | dyn_cast<TemplateTemplateParmDecl>(Template.getAsTemplateDecl())) | |||
5591 | if (TTP->getDepth() == Depth) | |||
5592 | Used[TTP->getIndex()] = true; | |||
5593 | RecursiveASTVisitor<MarkUsedTemplateParameterVisitor>:: | |||
5594 | TraverseTemplateName(Template); | |||
5595 | return true; | |||
5596 | } | |||
5597 | ||||
5598 | bool VisitDeclRefExpr(DeclRefExpr *E) { | |||
5599 | if (auto *NTTP = dyn_cast<NonTypeTemplateParmDecl>(E->getDecl())) | |||
5600 | if (NTTP->getDepth() == Depth) | |||
5601 | Used[NTTP->getIndex()] = true; | |||
5602 | return true; | |||
5603 | } | |||
5604 | }; | |||
5605 | } | |||
5606 | ||||
5607 | /// Mark the template parameters that are used by the given | |||
5608 | /// expression. | |||
5609 | static void | |||
5610 | MarkUsedTemplateParameters(ASTContext &Ctx, | |||
5611 | const Expr *E, | |||
5612 | bool OnlyDeduced, | |||
5613 | unsigned Depth, | |||
5614 | llvm::SmallBitVector &Used) { | |||
5615 | if (!OnlyDeduced) { | |||
5616 | MarkUsedTemplateParameterVisitor(Used, Depth) | |||
5617 | .TraverseStmt(const_cast<Expr *>(E)); | |||
5618 | return; | |||
5619 | } | |||
5620 | ||||
5621 | // We can deduce from a pack expansion. | |||
5622 | if (const PackExpansionExpr *Expansion = dyn_cast<PackExpansionExpr>(E)) | |||
5623 | E = Expansion->getPattern(); | |||
5624 | ||||
5625 | const NonTypeTemplateParmDecl *NTTP = getDeducedParameterFromExpr(E, Depth); | |||
5626 | if (!NTTP) | |||
5627 | return; | |||
5628 | ||||
5629 | if (NTTP->getDepth() == Depth) | |||
5630 | Used[NTTP->getIndex()] = true; | |||
5631 | ||||
5632 | // In C++17 mode, additional arguments may be deduced from the type of a | |||
5633 | // non-type argument. | |||
5634 | if (Ctx.getLangOpts().CPlusPlus17) | |||
5635 | MarkUsedTemplateParameters(Ctx, NTTP->getType(), OnlyDeduced, Depth, Used); | |||
5636 | } | |||
5637 | ||||
5638 | /// Mark the template parameters that are used by the given | |||
5639 | /// nested name specifier. | |||
5640 | static void | |||
5641 | MarkUsedTemplateParameters(ASTContext &Ctx, | |||
5642 | NestedNameSpecifier *NNS, | |||
5643 | bool OnlyDeduced, | |||
5644 | unsigned Depth, | |||
5645 | llvm::SmallBitVector &Used) { | |||
5646 | if (!NNS) | |||
5647 | return; | |||
5648 | ||||
5649 | MarkUsedTemplateParameters(Ctx, NNS->getPrefix(), OnlyDeduced, Depth, | |||
5650 | Used); | |||
5651 | MarkUsedTemplateParameters(Ctx, QualType(NNS->getAsType(), 0), | |||
5652 | OnlyDeduced, Depth, Used); | |||
5653 | } | |||
5654 | ||||
5655 | /// Mark the template parameters that are used by the given | |||
5656 | /// template name. | |||
5657 | static void | |||
5658 | MarkUsedTemplateParameters(ASTContext &Ctx, | |||
5659 | TemplateName Name, | |||
5660 | bool OnlyDeduced, | |||
5661 | unsigned Depth, | |||
5662 | llvm::SmallBitVector &Used) { | |||
5663 | if (TemplateDecl *Template = Name.getAsTemplateDecl()) { | |||
5664 | if (TemplateTemplateParmDecl *TTP | |||
5665 | = dyn_cast<TemplateTemplateParmDecl>(Template)) { | |||
5666 | if (TTP->getDepth() == Depth) | |||
5667 | Used[TTP->getIndex()] = true; | |||
5668 | } | |||
5669 | return; | |||
5670 | } | |||
5671 | ||||
5672 | if (QualifiedTemplateName *QTN = Name.getAsQualifiedTemplateName()) | |||
5673 | MarkUsedTemplateParameters(Ctx, QTN->getQualifier(), OnlyDeduced, | |||
5674 | Depth, Used); | |||
5675 | if (DependentTemplateName *DTN = Name.getAsDependentTemplateName()) | |||
5676 | MarkUsedTemplateParameters(Ctx, DTN->getQualifier(), OnlyDeduced, | |||
5677 | Depth, Used); | |||
5678 | } | |||
5679 | ||||
5680 | /// Mark the template parameters that are used by the given | |||
5681 | /// type. | |||
5682 | static void | |||
5683 | MarkUsedTemplateParameters(ASTContext &Ctx, QualType T, | |||
5684 | bool OnlyDeduced, | |||
5685 | unsigned Depth, | |||
5686 | llvm::SmallBitVector &Used) { | |||
5687 | if (T.isNull()) | |||
5688 | return; | |||
5689 | ||||
5690 | // Non-dependent types have nothing deducible | |||
5691 | if (!T->isDependentType()) | |||
5692 | return; | |||
5693 | ||||
5694 | T = Ctx.getCanonicalType(T); | |||
5695 | switch (T->getTypeClass()) { | |||
5696 | case Type::Pointer: | |||
5697 | MarkUsedTemplateParameters(Ctx, | |||
5698 | cast<PointerType>(T)->getPointeeType(), | |||
5699 | OnlyDeduced, | |||
5700 | Depth, | |||
5701 | Used); | |||
5702 | break; | |||
5703 | ||||
5704 | case Type::BlockPointer: | |||
5705 | MarkUsedTemplateParameters(Ctx, | |||
5706 | cast<BlockPointerType>(T)->getPointeeType(), | |||
5707 | OnlyDeduced, | |||
5708 | Depth, | |||
5709 | Used); | |||
5710 | break; | |||
5711 | ||||
5712 | case Type::LValueReference: | |||
5713 | case Type::RValueReference: | |||
5714 | MarkUsedTemplateParameters(Ctx, | |||
5715 | cast<ReferenceType>(T)->getPointeeType(), | |||
5716 | OnlyDeduced, | |||
5717 | Depth, | |||
5718 | Used); | |||
5719 | break; | |||
5720 | ||||
5721 | case Type::MemberPointer: { | |||
5722 | const MemberPointerType *MemPtr = cast<MemberPointerType>(T.getTypePtr()); | |||
5723 | MarkUsedTemplateParameters(Ctx, MemPtr->getPointeeType(), OnlyDeduced, | |||
5724 | Depth, Used); | |||
5725 | MarkUsedTemplateParameters(Ctx, QualType(MemPtr->getClass(), 0), | |||
5726 | OnlyDeduced, Depth, Used); | |||
5727 | break; | |||
5728 | } | |||
5729 | ||||
5730 | case Type::DependentSizedArray: | |||
5731 | MarkUsedTemplateParameters(Ctx, | |||
5732 | cast<DependentSizedArrayType>(T)->getSizeExpr(), | |||
5733 | OnlyDeduced, Depth, Used); | |||
5734 | // Fall through to check the element type | |||
5735 | LLVM_FALLTHROUGH[[gnu::fallthrough]]; | |||
5736 | ||||
5737 | case Type::ConstantArray: | |||
5738 | case Type::IncompleteArray: | |||
5739 | MarkUsedTemplateParameters(Ctx, | |||
5740 | cast<ArrayType>(T)->getElementType(), | |||
5741 | OnlyDeduced, Depth, Used); | |||
5742 | break; | |||
5743 | ||||
5744 | case Type::Vector: | |||
5745 | case Type::ExtVector: | |||
5746 | MarkUsedTemplateParameters(Ctx, | |||
5747 | cast<VectorType>(T)->getElementType(), | |||
5748 | OnlyDeduced, Depth, Used); | |||
5749 | break; | |||
5750 | ||||
5751 | case Type::DependentVector: { | |||
5752 | const auto *VecType = cast<DependentVectorType>(T); | |||
5753 | MarkUsedTemplateParameters(Ctx, VecType->getElementType(), OnlyDeduced, | |||
5754 | Depth, Used); | |||
5755 | MarkUsedTemplateParameters(Ctx, VecType->getSizeExpr(), OnlyDeduced, Depth, | |||
5756 | Used); | |||
5757 | break; | |||
5758 | } | |||
5759 | case Type::DependentSizedExtVector: { | |||
5760 | const DependentSizedExtVectorType *VecType | |||
5761 | = cast<DependentSizedExtVectorType>(T); | |||
5762 | MarkUsedTemplateParameters(Ctx, VecType->getElementType(), OnlyDeduced, | |||
5763 | Depth, Used); | |||
5764 | MarkUsedTemplateParameters(Ctx, VecType->getSizeExpr(), OnlyDeduced, | |||
5765 | Depth, Used); | |||
5766 | break; | |||
5767 | } | |||
5768 | ||||
5769 | case Type::DependentAddressSpace: { | |||
5770 | const DependentAddressSpaceType *DependentASType = | |||
5771 | cast<DependentAddressSpaceType>(T); | |||
5772 | MarkUsedTemplateParameters(Ctx, DependentASType->getPointeeType(), | |||
5773 | OnlyDeduced, Depth, Used); | |||
5774 | MarkUsedTemplateParameters(Ctx, | |||
5775 | DependentASType->getAddrSpaceExpr(), | |||
5776 | OnlyDeduced, Depth, Used); | |||
5777 | break; | |||
5778 | } | |||
5779 | ||||
5780 | case Type::ConstantMatrix: { | |||
5781 | const ConstantMatrixType *MatType = cast<ConstantMatrixType>(T); | |||
5782 | MarkUsedTemplateParameters(Ctx, MatType->getElementType(), OnlyDeduced, | |||
5783 | Depth, Used); | |||
5784 | break; | |||
5785 | } | |||
5786 | ||||
5787 | case Type::DependentSizedMatrix: { | |||
5788 | const DependentSizedMatrixType *MatType = cast<DependentSizedMatrixType>(T); | |||
5789 | MarkUsedTemplateParameters(Ctx, MatType->getElementType(), OnlyDeduced, | |||
5790 | Depth, Used); | |||
5791 | MarkUsedTemplateParameters(Ctx, MatType->getRowExpr(), OnlyDeduced, Depth, | |||
5792 | Used); | |||
5793 | MarkUsedTemplateParameters(Ctx, MatType->getColumnExpr(), OnlyDeduced, | |||
5794 | Depth, Used); | |||
5795 | break; | |||
5796 | } | |||
5797 | ||||
5798 | case Type::FunctionProto: { | |||
5799 | const FunctionProtoType *Proto = cast<FunctionProtoType>(T); | |||
5800 | MarkUsedTemplateParameters(Ctx, Proto->getReturnType(), OnlyDeduced, Depth, | |||
5801 | Used); | |||
5802 | for (unsigned I = 0, N = Proto->getNumParams(); I != N; ++I) { | |||
5803 | // C++17 [temp.deduct.type]p5: | |||
5804 | // The non-deduced contexts are: [...] | |||
5805 | // -- A function parameter pack that does not occur at the end of the | |||
5806 | // parameter-declaration-list. | |||
5807 | if (!OnlyDeduced || I + 1 == N || | |||
5808 | !Proto->getParamType(I)->getAs<PackExpansionType>()) { | |||
5809 | MarkUsedTemplateParameters(Ctx, Proto->getParamType(I), OnlyDeduced, | |||
5810 | Depth, Used); | |||
5811 | } else { | |||
5812 | // FIXME: C++17 [temp.deduct.call]p1: | |||
5813 | // When a function parameter pack appears in a non-deduced context, | |||
5814 | // the type of that pack is never deduced. | |||
5815 | // | |||
5816 | // We should also track a set of "never deduced" parameters, and | |||
5817 | // subtract that from the list of deduced parameters after marking. | |||
5818 | } | |||
5819 | } | |||
5820 | if (auto *E = Proto->getNoexceptExpr()) | |||
5821 | MarkUsedTemplateParameters(Ctx, E, OnlyDeduced, Depth, Used); | |||
5822 | break; | |||
5823 | } | |||
5824 | ||||
5825 | case Type::TemplateTypeParm: { | |||
5826 | const TemplateTypeParmType *TTP = cast<TemplateTypeParmType>(T); | |||
5827 | if (TTP->getDepth() == Depth) | |||
5828 | Used[TTP->getIndex()] = true; | |||
5829 | break; | |||
5830 | } | |||
5831 | ||||
5832 | case Type::SubstTemplateTypeParmPack: { | |||
5833 | const SubstTemplateTypeParmPackType *Subst | |||
5834 | = cast<SubstTemplateTypeParmPackType>(T); | |||
5835 | MarkUsedTemplateParameters(Ctx, | |||
5836 | QualType(Subst->getReplacedParameter(), 0), | |||
5837 | OnlyDeduced, Depth, Used); | |||
5838 | MarkUsedTemplateParameters(Ctx, Subst->getArgumentPack(), | |||
5839 | OnlyDeduced, Depth, Used); | |||
5840 | break; | |||
5841 | } | |||
5842 | ||||
5843 | case Type::InjectedClassName: | |||
5844 | T = cast<InjectedClassNameType>(T)->getInjectedSpecializationType(); | |||
5845 | LLVM_FALLTHROUGH[[gnu::fallthrough]]; | |||
5846 | ||||
5847 | case Type::TemplateSpecialization: { | |||
5848 | const TemplateSpecializationType *Spec | |||
5849 | = cast<TemplateSpecializationType>(T); | |||
5850 | MarkUsedTemplateParameters(Ctx, Spec->getTemplateName(), OnlyDeduced, | |||
5851 | Depth, Used); | |||
5852 | ||||
5853 | // C++0x [temp.deduct.type]p9: | |||
5854 | // If the template argument list of P contains a pack expansion that is | |||
5855 | // not the last template argument, the entire template argument list is a | |||
5856 | // non-deduced context. | |||
5857 | if (OnlyDeduced && | |||
5858 | hasPackExpansionBeforeEnd(Spec->template_arguments())) | |||
5859 | break; | |||
5860 | ||||
5861 | for (unsigned I = 0, N = Spec->getNumArgs(); I != N; ++I) | |||
5862 | MarkUsedTemplateParameters(Ctx, Spec->getArg(I), OnlyDeduced, Depth, | |||
5863 | Used); | |||
5864 | break; | |||
5865 | } | |||
5866 | ||||
5867 | case Type::Complex: | |||
5868 | if (!OnlyDeduced) | |||
5869 | MarkUsedTemplateParameters(Ctx, | |||
5870 | cast<ComplexType>(T)->getElementType(), | |||
5871 | OnlyDeduced, Depth, Used); | |||
5872 | break; | |||
5873 | ||||
5874 | case Type::Atomic: | |||
5875 | if (!OnlyDeduced) | |||
5876 | MarkUsedTemplateParameters(Ctx, | |||
5877 | cast<AtomicType>(T)->getValueType(), | |||
5878 | OnlyDeduced, Depth, Used); | |||
5879 | break; | |||
5880 | ||||
5881 | case Type::DependentName: | |||
5882 | if (!OnlyDeduced) | |||
5883 | MarkUsedTemplateParameters(Ctx, | |||
5884 | cast<DependentNameType>(T)->getQualifier(), | |||
5885 | OnlyDeduced, Depth, Used); | |||
5886 | break; | |||
5887 | ||||
5888 | case Type::DependentTemplateSpecialization: { | |||
5889 | // C++14 [temp.deduct.type]p5: | |||
5890 | // The non-deduced contexts are: | |||
5891 | // -- The nested-name-specifier of a type that was specified using a | |||
5892 | // qualified-id | |||
5893 | // | |||
5894 | // C++14 [temp.deduct.type]p6: | |||
5895 | // When a type name is specified in a way that includes a non-deduced | |||
5896 | // context, all of the types that comprise that type name are also | |||
5897 | // non-deduced. | |||
5898 | if (OnlyDeduced) | |||
5899 | break; | |||
5900 | ||||
5901 | const DependentTemplateSpecializationType *Spec | |||
5902 | = cast<DependentTemplateSpecializationType>(T); | |||
5903 | ||||
5904 | MarkUsedTemplateParameters(Ctx, Spec->getQualifier(), | |||
5905 | OnlyDeduced, Depth, Used); | |||
5906 | ||||
5907 | for (unsigned I = 0, N = Spec->getNumArgs(); I != N; ++I) | |||
5908 | MarkUsedTemplateParameters(Ctx, Spec->getArg(I), OnlyDeduced, Depth, | |||
5909 | Used); | |||
5910 | break; | |||
5911 | } | |||
5912 | ||||
5913 | case Type::TypeOf: | |||
5914 | if (!OnlyDeduced) | |||
5915 | MarkUsedTemplateParameters(Ctx, | |||
5916 | cast<TypeOfType>(T)->getUnderlyingType(), | |||
5917 | OnlyDeduced, Depth, Used); | |||
5918 | break; | |||
5919 | ||||
5920 | case Type::TypeOfExpr: | |||
5921 | if (!OnlyDeduced) | |||
5922 | MarkUsedTemplateParameters(Ctx, | |||
5923 | cast<TypeOfExprType>(T)->getUnderlyingExpr(), | |||
5924 | OnlyDeduced, Depth, Used); | |||
5925 | break; | |||
5926 | ||||
5927 | case Type::Decltype: | |||
5928 | if (!OnlyDeduced) | |||
5929 | MarkUsedTemplateParameters(Ctx, | |||
5930 | cast<DecltypeType>(T)->getUnderlyingExpr(), | |||
5931 | OnlyDeduced, Depth, Used); | |||
5932 | break; | |||
5933 | ||||
5934 | case Type::UnaryTransform: | |||
5935 | if (!OnlyDeduced) | |||
5936 | MarkUsedTemplateParameters(Ctx, | |||
5937 | cast<UnaryTransformType>(T)->getUnderlyingType(), | |||
5938 | OnlyDeduced, Depth, Used); | |||
5939 | break; | |||
5940 | ||||
5941 | case Type::PackExpansion: | |||
5942 | MarkUsedTemplateParameters(Ctx, | |||
5943 | cast<PackExpansionType>(T)->getPattern(), | |||
5944 | OnlyDeduced, Depth, Used); | |||
5945 | break; | |||
5946 | ||||
5947 | case Type::Auto: | |||
5948 | case Type::DeducedTemplateSpecialization: | |||
5949 | MarkUsedTemplateParameters(Ctx, | |||
5950 | cast<DeducedType>(T)->getDeducedType(), | |||
5951 | OnlyDeduced, Depth, Used); | |||
5952 | break; | |||
5953 | case Type::DependentBitInt: | |||
5954 | MarkUsedTemplateParameters(Ctx, | |||
5955 | cast<DependentBitIntType>(T)->getNumBitsExpr(), | |||
5956 | OnlyDeduced, Depth, Used); | |||
5957 | break; | |||
5958 | ||||
5959 | // None of these types have any template parameters in them. | |||
5960 | case Type::Builtin: | |||
5961 | case Type::VariableArray: | |||
5962 | case Type::FunctionNoProto: | |||
5963 | case Type::Record: | |||
5964 | case Type::Enum: | |||
5965 | case Type::ObjCInterface: | |||
5966 | case Type::ObjCObject: | |||
5967 | case Type::ObjCObjectPointer: | |||
5968 | case Type::UnresolvedUsing: | |||
5969 | case Type::Pipe: | |||
5970 | case Type::BitInt: | |||
5971 | #define TYPE(Class, Base) | |||
5972 | #define ABSTRACT_TYPE(Class, Base) | |||
5973 | #define DEPENDENT_TYPE(Class, Base) | |||
5974 | #define NON_CANONICAL_TYPE(Class, Base) case Type::Class: | |||
5975 | #include "clang/AST/TypeNodes.inc" | |||
5976 | break; | |||
5977 | } | |||
5978 | } | |||
5979 | ||||
5980 | /// Mark the template parameters that are used by this | |||
5981 | /// template argument. | |||
5982 | static void | |||
5983 | MarkUsedTemplateParameters(ASTContext &Ctx, | |||
5984 | const TemplateArgument &TemplateArg, | |||
5985 | bool OnlyDeduced, | |||
5986 | unsigned Depth, | |||
5987 | llvm::SmallBitVector &Used) { | |||
5988 | switch (TemplateArg.getKind()) { | |||
5989 | case TemplateArgument::Null: | |||
5990 | case TemplateArgument::Integral: | |||
5991 | case TemplateArgument::Declaration: | |||
5992 | break; | |||
5993 | ||||
5994 | case TemplateArgument::NullPtr: | |||
5995 | MarkUsedTemplateParameters(Ctx, TemplateArg.getNullPtrType(), OnlyDeduced, | |||
5996 | Depth, Used); | |||
5997 | break; | |||
5998 | ||||
5999 | case TemplateArgument::Type: | |||
6000 | MarkUsedTemplateParameters(Ctx, TemplateArg.getAsType(), OnlyDeduced, | |||
6001 | Depth, Used); | |||
6002 | break; | |||
6003 | ||||
6004 | case TemplateArgument::Template: | |||
6005 | case TemplateArgument::TemplateExpansion: | |||
6006 | MarkUsedTemplateParameters(Ctx, | |||
6007 | TemplateArg.getAsTemplateOrTemplatePattern(), | |||
6008 | OnlyDeduced, Depth, Used); | |||
6009 | break; | |||
6010 | ||||
6011 | case TemplateArgument::Expression: | |||
6012 | MarkUsedTemplateParameters(Ctx, TemplateArg.getAsExpr(), OnlyDeduced, | |||
6013 | Depth, Used); | |||
6014 | break; | |||
6015 | ||||
6016 | case TemplateArgument::Pack: | |||
6017 | for (const auto &P : TemplateArg.pack_elements()) | |||
6018 | MarkUsedTemplateParameters(Ctx, P, OnlyDeduced, Depth, Used); | |||
6019 | break; | |||
6020 | } | |||
6021 | } | |||
6022 | ||||
6023 | /// Mark which template parameters are used in a given expression. | |||
6024 | /// | |||
6025 | /// \param E the expression from which template parameters will be deduced. | |||
6026 | /// | |||
6027 | /// \param Used a bit vector whose elements will be set to \c true | |||
6028 | /// to indicate when the corresponding template parameter will be | |||
6029 | /// deduced. | |||
6030 | void | |||
6031 | Sema::MarkUsedTemplateParameters(const Expr *E, bool OnlyDeduced, | |||
6032 | unsigned Depth, | |||
6033 | llvm::SmallBitVector &Used) { | |||
6034 | ::MarkUsedTemplateParameters(Context, E, OnlyDeduced, Depth, Used); | |||
6035 | } | |||
6036 | ||||
6037 | /// Mark which template parameters can be deduced from a given | |||
6038 | /// template argument list. | |||
6039 | /// | |||
6040 | /// \param TemplateArgs the template argument list from which template | |||
6041 | /// parameters will be deduced. | |||
6042 | /// | |||
6043 | /// \param Used a bit vector whose elements will be set to \c true | |||
6044 | /// to indicate when the corresponding template parameter will be | |||
6045 | /// deduced. | |||
6046 | void | |||
6047 | Sema::MarkUsedTemplateParameters(const TemplateArgumentList &TemplateArgs, | |||
6048 | bool OnlyDeduced, unsigned Depth, | |||
6049 | llvm::SmallBitVector &Used) { | |||
6050 | // C++0x [temp.deduct.type]p9: | |||
6051 | // If the template argument list of P contains a pack expansion that is not | |||
6052 | // the last template argument, the entire template argument list is a | |||
6053 | // non-deduced context. | |||
6054 | if (OnlyDeduced && | |||
6055 | hasPackExpansionBeforeEnd(TemplateArgs.asArray())) | |||
6056 | return; | |||
6057 | ||||
6058 | for (unsigned I = 0, N = TemplateArgs.size(); I != N; ++I) | |||
6059 | ::MarkUsedTemplateParameters(Context, TemplateArgs[I], OnlyDeduced, | |||
6060 | Depth, Used); | |||
6061 | } | |||
6062 | ||||
6063 | /// Marks all of the template parameters that will be deduced by a | |||
6064 | /// call to the given function template. | |||
6065 | void Sema::MarkDeducedTemplateParameters( | |||
6066 | ASTContext &Ctx, const FunctionTemplateDecl *FunctionTemplate, | |||
6067 | llvm::SmallBitVector &Deduced) { | |||
6068 | TemplateParameterList *TemplateParams | |||
6069 | = FunctionTemplate->getTemplateParameters(); | |||
6070 | Deduced.clear(); | |||
6071 | Deduced.resize(TemplateParams->size()); | |||
6072 | ||||
6073 | FunctionDecl *Function = FunctionTemplate->getTemplatedDecl(); | |||
6074 | for (unsigned I = 0, N = Function->getNumParams(); I != N; ++I) | |||
6075 | ::MarkUsedTemplateParameters(Ctx, Function->getParamDecl(I)->getType(), | |||
6076 | true, TemplateParams->getDepth(), Deduced); | |||
6077 | } | |||
6078 | ||||
6079 | bool hasDeducibleTemplateParameters(Sema &S, | |||
6080 | FunctionTemplateDecl *FunctionTemplate, | |||
6081 | QualType T) { | |||
6082 | if (!T->isDependentType()) | |||
6083 | return false; | |||
6084 | ||||
6085 | TemplateParameterList *TemplateParams | |||
6086 | = FunctionTemplate->getTemplateParameters(); | |||
6087 | llvm::SmallBitVector Deduced(TemplateParams->size()); | |||
6088 | ::MarkUsedTemplateParameters(S.Context, T, true, TemplateParams->getDepth(), | |||
6089 | Deduced); | |||
6090 | ||||
6091 | return Deduced.any(); | |||
6092 | } |