File: | clang/lib/Sema/SemaCoroutine.cpp |
Warning: | line 683, column 25 Called C++ object pointer is null |
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1 | //===-- SemaCoroutine.cpp - Semantic Analysis for Coroutines --------------===// | ||||
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 semantic analysis for C++ Coroutines. | ||||
10 | // | ||||
11 | // This file contains references to sections of the Coroutines TS, which | ||||
12 | // can be found at http://wg21.link/coroutines. | ||||
13 | // | ||||
14 | //===----------------------------------------------------------------------===// | ||||
15 | |||||
16 | #include "CoroutineStmtBuilder.h" | ||||
17 | #include "clang/AST/ASTLambda.h" | ||||
18 | #include "clang/AST/Decl.h" | ||||
19 | #include "clang/AST/ExprCXX.h" | ||||
20 | #include "clang/AST/StmtCXX.h" | ||||
21 | #include "clang/Basic/Builtins.h" | ||||
22 | #include "clang/Lex/Preprocessor.h" | ||||
23 | #include "clang/Sema/Initialization.h" | ||||
24 | #include "clang/Sema/Overload.h" | ||||
25 | #include "clang/Sema/ScopeInfo.h" | ||||
26 | #include "clang/Sema/SemaInternal.h" | ||||
27 | #include "llvm/ADT/SmallSet.h" | ||||
28 | |||||
29 | using namespace clang; | ||||
30 | using namespace sema; | ||||
31 | |||||
32 | static LookupResult lookupMember(Sema &S, const char *Name, CXXRecordDecl *RD, | ||||
33 | SourceLocation Loc, bool &Res) { | ||||
34 | DeclarationName DN = S.PP.getIdentifierInfo(Name); | ||||
35 | LookupResult LR(S, DN, Loc, Sema::LookupMemberName); | ||||
36 | // Suppress diagnostics when a private member is selected. The same warnings | ||||
37 | // will be produced again when building the call. | ||||
38 | LR.suppressDiagnostics(); | ||||
39 | Res = S.LookupQualifiedName(LR, RD); | ||||
40 | return LR; | ||||
41 | } | ||||
42 | |||||
43 | static bool lookupMember(Sema &S, const char *Name, CXXRecordDecl *RD, | ||||
44 | SourceLocation Loc) { | ||||
45 | bool Res; | ||||
46 | lookupMember(S, Name, RD, Loc, Res); | ||||
47 | return Res; | ||||
48 | } | ||||
49 | |||||
50 | /// Look up the std::coroutine_traits<...>::promise_type for the given | ||||
51 | /// function type. | ||||
52 | static QualType lookupPromiseType(Sema &S, const FunctionDecl *FD, | ||||
53 | SourceLocation KwLoc) { | ||||
54 | const FunctionProtoType *FnType = FD->getType()->castAs<FunctionProtoType>(); | ||||
55 | const SourceLocation FuncLoc = FD->getLocation(); | ||||
56 | |||||
57 | NamespaceDecl *CoroNamespace = nullptr; | ||||
58 | ClassTemplateDecl *CoroTraits = | ||||
59 | S.lookupCoroutineTraits(KwLoc, FuncLoc, CoroNamespace); | ||||
60 | if (!CoroTraits) { | ||||
61 | return QualType(); | ||||
62 | } | ||||
63 | |||||
64 | // Form template argument list for coroutine_traits<R, P1, P2, ...> according | ||||
65 | // to [dcl.fct.def.coroutine]3 | ||||
66 | TemplateArgumentListInfo Args(KwLoc, KwLoc); | ||||
67 | auto AddArg = [&](QualType T) { | ||||
68 | Args.addArgument(TemplateArgumentLoc( | ||||
69 | TemplateArgument(T), S.Context.getTrivialTypeSourceInfo(T, KwLoc))); | ||||
70 | }; | ||||
71 | AddArg(FnType->getReturnType()); | ||||
72 | // If the function is a non-static member function, add the type | ||||
73 | // of the implicit object parameter before the formal parameters. | ||||
74 | if (auto *MD = dyn_cast<CXXMethodDecl>(FD)) { | ||||
75 | if (MD->isInstance()) { | ||||
76 | // [over.match.funcs]4 | ||||
77 | // For non-static member functions, the type of the implicit object | ||||
78 | // parameter is | ||||
79 | // -- "lvalue reference to cv X" for functions declared without a | ||||
80 | // ref-qualifier or with the & ref-qualifier | ||||
81 | // -- "rvalue reference to cv X" for functions declared with the && | ||||
82 | // ref-qualifier | ||||
83 | QualType T = MD->getThisType()->castAs<PointerType>()->getPointeeType(); | ||||
84 | T = FnType->getRefQualifier() == RQ_RValue | ||||
85 | ? S.Context.getRValueReferenceType(T) | ||||
86 | : S.Context.getLValueReferenceType(T, /*SpelledAsLValue*/ true); | ||||
87 | AddArg(T); | ||||
88 | } | ||||
89 | } | ||||
90 | for (QualType T : FnType->getParamTypes()) | ||||
91 | AddArg(T); | ||||
92 | |||||
93 | // Build the template-id. | ||||
94 | QualType CoroTrait = | ||||
95 | S.CheckTemplateIdType(TemplateName(CoroTraits), KwLoc, Args); | ||||
96 | if (CoroTrait.isNull()) | ||||
97 | return QualType(); | ||||
98 | if (S.RequireCompleteType(KwLoc, CoroTrait, | ||||
99 | diag::err_coroutine_type_missing_specialization)) | ||||
100 | return QualType(); | ||||
101 | |||||
102 | auto *RD = CoroTrait->getAsCXXRecordDecl(); | ||||
103 | assert(RD && "specialization of class template is not a class?")(static_cast <bool> (RD && "specialization of class template is not a class?" ) ? void (0) : __assert_fail ("RD && \"specialization of class template is not a class?\"" , "clang/lib/Sema/SemaCoroutine.cpp", 103, __extension__ __PRETTY_FUNCTION__ )); | ||||
104 | |||||
105 | // Look up the ::promise_type member. | ||||
106 | LookupResult R(S, &S.PP.getIdentifierTable().get("promise_type"), KwLoc, | ||||
107 | Sema::LookupOrdinaryName); | ||||
108 | S.LookupQualifiedName(R, RD); | ||||
109 | auto *Promise = R.getAsSingle<TypeDecl>(); | ||||
110 | if (!Promise) { | ||||
111 | S.Diag(FuncLoc, | ||||
112 | diag::err_implied_std_coroutine_traits_promise_type_not_found) | ||||
113 | << RD; | ||||
114 | return QualType(); | ||||
115 | } | ||||
116 | // The promise type is required to be a class type. | ||||
117 | QualType PromiseType = S.Context.getTypeDeclType(Promise); | ||||
118 | |||||
119 | auto buildElaboratedType = [&]() { | ||||
120 | auto *NNS = NestedNameSpecifier::Create(S.Context, nullptr, CoroNamespace); | ||||
121 | NNS = NestedNameSpecifier::Create(S.Context, NNS, false, | ||||
122 | CoroTrait.getTypePtr()); | ||||
123 | return S.Context.getElaboratedType(ETK_None, NNS, PromiseType); | ||||
124 | }; | ||||
125 | |||||
126 | if (!PromiseType->getAsCXXRecordDecl()) { | ||||
127 | S.Diag(FuncLoc, | ||||
128 | diag::err_implied_std_coroutine_traits_promise_type_not_class) | ||||
129 | << buildElaboratedType(); | ||||
130 | return QualType(); | ||||
131 | } | ||||
132 | if (S.RequireCompleteType(FuncLoc, buildElaboratedType(), | ||||
133 | diag::err_coroutine_promise_type_incomplete)) | ||||
134 | return QualType(); | ||||
135 | |||||
136 | return PromiseType; | ||||
137 | } | ||||
138 | |||||
139 | /// Look up the std::coroutine_handle<PromiseType>. | ||||
140 | static QualType lookupCoroutineHandleType(Sema &S, QualType PromiseType, | ||||
141 | SourceLocation Loc) { | ||||
142 | if (PromiseType.isNull()) | ||||
143 | return QualType(); | ||||
144 | |||||
145 | NamespaceDecl *CoroNamespace = S.getCachedCoroNamespace(); | ||||
146 | assert(CoroNamespace && "Should already be diagnosed")(static_cast <bool> (CoroNamespace && "Should already be diagnosed" ) ? void (0) : __assert_fail ("CoroNamespace && \"Should already be diagnosed\"" , "clang/lib/Sema/SemaCoroutine.cpp", 146, __extension__ __PRETTY_FUNCTION__ )); | ||||
147 | |||||
148 | LookupResult Result(S, &S.PP.getIdentifierTable().get("coroutine_handle"), | ||||
149 | Loc, Sema::LookupOrdinaryName); | ||||
150 | if (!S.LookupQualifiedName(Result, CoroNamespace)) { | ||||
151 | S.Diag(Loc, diag::err_implied_coroutine_type_not_found) | ||||
152 | << "std::coroutine_handle"; | ||||
153 | return QualType(); | ||||
154 | } | ||||
155 | |||||
156 | ClassTemplateDecl *CoroHandle = Result.getAsSingle<ClassTemplateDecl>(); | ||||
157 | if (!CoroHandle) { | ||||
158 | Result.suppressDiagnostics(); | ||||
159 | // We found something weird. Complain about the first thing we found. | ||||
160 | NamedDecl *Found = *Result.begin(); | ||||
161 | S.Diag(Found->getLocation(), diag::err_malformed_std_coroutine_handle); | ||||
162 | return QualType(); | ||||
163 | } | ||||
164 | |||||
165 | // Form template argument list for coroutine_handle<Promise>. | ||||
166 | TemplateArgumentListInfo Args(Loc, Loc); | ||||
167 | Args.addArgument(TemplateArgumentLoc( | ||||
168 | TemplateArgument(PromiseType), | ||||
169 | S.Context.getTrivialTypeSourceInfo(PromiseType, Loc))); | ||||
170 | |||||
171 | // Build the template-id. | ||||
172 | QualType CoroHandleType = | ||||
173 | S.CheckTemplateIdType(TemplateName(CoroHandle), Loc, Args); | ||||
174 | if (CoroHandleType.isNull()) | ||||
175 | return QualType(); | ||||
176 | if (S.RequireCompleteType(Loc, CoroHandleType, | ||||
177 | diag::err_coroutine_type_missing_specialization)) | ||||
178 | return QualType(); | ||||
179 | |||||
180 | return CoroHandleType; | ||||
181 | } | ||||
182 | |||||
183 | static bool isValidCoroutineContext(Sema &S, SourceLocation Loc, | ||||
184 | StringRef Keyword) { | ||||
185 | // [expr.await]p2 dictates that 'co_await' and 'co_yield' must be used within | ||||
186 | // a function body. | ||||
187 | // FIXME: This also covers [expr.await]p2: "An await-expression shall not | ||||
188 | // appear in a default argument." But the diagnostic QoI here could be | ||||
189 | // improved to inform the user that default arguments specifically are not | ||||
190 | // allowed. | ||||
191 | auto *FD = dyn_cast<FunctionDecl>(S.CurContext); | ||||
192 | if (!FD) { | ||||
193 | S.Diag(Loc, isa<ObjCMethodDecl>(S.CurContext) | ||||
194 | ? diag::err_coroutine_objc_method | ||||
195 | : diag::err_coroutine_outside_function) << Keyword; | ||||
196 | return false; | ||||
197 | } | ||||
198 | |||||
199 | // An enumeration for mapping the diagnostic type to the correct diagnostic | ||||
200 | // selection index. | ||||
201 | enum InvalidFuncDiag { | ||||
202 | DiagCtor = 0, | ||||
203 | DiagDtor, | ||||
204 | DiagMain, | ||||
205 | DiagConstexpr, | ||||
206 | DiagAutoRet, | ||||
207 | DiagVarargs, | ||||
208 | DiagConsteval, | ||||
209 | }; | ||||
210 | bool Diagnosed = false; | ||||
211 | auto DiagInvalid = [&](InvalidFuncDiag ID) { | ||||
212 | S.Diag(Loc, diag::err_coroutine_invalid_func_context) << ID << Keyword; | ||||
213 | Diagnosed = true; | ||||
214 | return false; | ||||
215 | }; | ||||
216 | |||||
217 | // Diagnose when a constructor, destructor | ||||
218 | // or the function 'main' are declared as a coroutine. | ||||
219 | auto *MD = dyn_cast<CXXMethodDecl>(FD); | ||||
220 | // [class.ctor]p11: "A constructor shall not be a coroutine." | ||||
221 | if (MD && isa<CXXConstructorDecl>(MD)) | ||||
222 | return DiagInvalid(DiagCtor); | ||||
223 | // [class.dtor]p17: "A destructor shall not be a coroutine." | ||||
224 | else if (MD && isa<CXXDestructorDecl>(MD)) | ||||
225 | return DiagInvalid(DiagDtor); | ||||
226 | // [basic.start.main]p3: "The function main shall not be a coroutine." | ||||
227 | else if (FD->isMain()) | ||||
228 | return DiagInvalid(DiagMain); | ||||
229 | |||||
230 | // Emit a diagnostics for each of the following conditions which is not met. | ||||
231 | // [expr.const]p2: "An expression e is a core constant expression unless the | ||||
232 | // evaluation of e [...] would evaluate one of the following expressions: | ||||
233 | // [...] an await-expression [...] a yield-expression." | ||||
234 | if (FD->isConstexpr()) | ||||
235 | DiagInvalid(FD->isConsteval() ? DiagConsteval : DiagConstexpr); | ||||
236 | // [dcl.spec.auto]p15: "A function declared with a return type that uses a | ||||
237 | // placeholder type shall not be a coroutine." | ||||
238 | if (FD->getReturnType()->isUndeducedType()) | ||||
239 | DiagInvalid(DiagAutoRet); | ||||
240 | // [dcl.fct.def.coroutine]p1 | ||||
241 | // The parameter-declaration-clause of the coroutine shall not terminate with | ||||
242 | // an ellipsis that is not part of a parameter-declaration. | ||||
243 | if (FD->isVariadic()) | ||||
244 | DiagInvalid(DiagVarargs); | ||||
245 | |||||
246 | return !Diagnosed; | ||||
247 | } | ||||
248 | |||||
249 | static ExprResult buildOperatorCoawaitLookupExpr(Sema &SemaRef, Scope *S, | ||||
250 | SourceLocation Loc) { | ||||
251 | DeclarationName OpName = | ||||
252 | SemaRef.Context.DeclarationNames.getCXXOperatorName(OO_Coawait); | ||||
253 | LookupResult Operators(SemaRef, OpName, SourceLocation(), | ||||
254 | Sema::LookupOperatorName); | ||||
255 | SemaRef.LookupName(Operators, S); | ||||
256 | |||||
257 | assert(!Operators.isAmbiguous() && "Operator lookup cannot be ambiguous")(static_cast <bool> (!Operators.isAmbiguous() && "Operator lookup cannot be ambiguous") ? void (0) : __assert_fail ("!Operators.isAmbiguous() && \"Operator lookup cannot be ambiguous\"" , "clang/lib/Sema/SemaCoroutine.cpp", 257, __extension__ __PRETTY_FUNCTION__ )); | ||||
258 | const auto &Functions = Operators.asUnresolvedSet(); | ||||
259 | bool IsOverloaded = | ||||
260 | Functions.size() > 1 || | ||||
261 | (Functions.size() == 1 && isa<FunctionTemplateDecl>(*Functions.begin())); | ||||
262 | Expr *CoawaitOp = UnresolvedLookupExpr::Create( | ||||
263 | SemaRef.Context, /*NamingClass*/ nullptr, NestedNameSpecifierLoc(), | ||||
264 | DeclarationNameInfo(OpName, Loc), /*RequiresADL*/ true, IsOverloaded, | ||||
265 | Functions.begin(), Functions.end()); | ||||
266 | assert(CoawaitOp)(static_cast <bool> (CoawaitOp) ? void (0) : __assert_fail ("CoawaitOp", "clang/lib/Sema/SemaCoroutine.cpp", 266, __extension__ __PRETTY_FUNCTION__)); | ||||
267 | return CoawaitOp; | ||||
268 | } | ||||
269 | |||||
270 | /// Build a call to 'operator co_await' if there is a suitable operator for | ||||
271 | /// the given expression. | ||||
272 | static ExprResult buildOperatorCoawaitCall(Sema &SemaRef, SourceLocation Loc, | ||||
273 | Expr *E, | ||||
274 | UnresolvedLookupExpr *Lookup) { | ||||
275 | UnresolvedSet<16> Functions; | ||||
276 | Functions.append(Lookup->decls_begin(), Lookup->decls_end()); | ||||
277 | return SemaRef.CreateOverloadedUnaryOp(Loc, UO_Coawait, Functions, E); | ||||
278 | } | ||||
279 | |||||
280 | static ExprResult buildOperatorCoawaitCall(Sema &SemaRef, Scope *S, | ||||
281 | SourceLocation Loc, Expr *E) { | ||||
282 | ExprResult R = buildOperatorCoawaitLookupExpr(SemaRef, S, Loc); | ||||
283 | if (R.isInvalid()) | ||||
284 | return ExprError(); | ||||
285 | return buildOperatorCoawaitCall(SemaRef, Loc, E, | ||||
286 | cast<UnresolvedLookupExpr>(R.get())); | ||||
287 | } | ||||
288 | |||||
289 | static ExprResult buildCoroutineHandle(Sema &S, QualType PromiseType, | ||||
290 | SourceLocation Loc) { | ||||
291 | QualType CoroHandleType = lookupCoroutineHandleType(S, PromiseType, Loc); | ||||
292 | if (CoroHandleType.isNull()) | ||||
293 | return ExprError(); | ||||
294 | |||||
295 | DeclContext *LookupCtx = S.computeDeclContext(CoroHandleType); | ||||
296 | LookupResult Found(S, &S.PP.getIdentifierTable().get("from_address"), Loc, | ||||
297 | Sema::LookupOrdinaryName); | ||||
298 | if (!S.LookupQualifiedName(Found, LookupCtx)) { | ||||
299 | S.Diag(Loc, diag::err_coroutine_handle_missing_member) | ||||
300 | << "from_address"; | ||||
301 | return ExprError(); | ||||
302 | } | ||||
303 | |||||
304 | Expr *FramePtr = | ||||
305 | S.BuildBuiltinCallExpr(Loc, Builtin::BI__builtin_coro_frame, {}); | ||||
306 | |||||
307 | CXXScopeSpec SS; | ||||
308 | ExprResult FromAddr = | ||||
309 | S.BuildDeclarationNameExpr(SS, Found, /*NeedsADL=*/false); | ||||
310 | if (FromAddr.isInvalid()) | ||||
311 | return ExprError(); | ||||
312 | |||||
313 | return S.BuildCallExpr(nullptr, FromAddr.get(), Loc, FramePtr, Loc); | ||||
314 | } | ||||
315 | |||||
316 | struct ReadySuspendResumeResult { | ||||
317 | enum AwaitCallType { ACT_Ready, ACT_Suspend, ACT_Resume }; | ||||
318 | Expr *Results[3]; | ||||
319 | OpaqueValueExpr *OpaqueValue; | ||||
320 | bool IsInvalid; | ||||
321 | }; | ||||
322 | |||||
323 | static ExprResult buildMemberCall(Sema &S, Expr *Base, SourceLocation Loc, | ||||
324 | StringRef Name, MultiExprArg Args) { | ||||
325 | DeclarationNameInfo NameInfo(&S.PP.getIdentifierTable().get(Name), Loc); | ||||
326 | |||||
327 | // FIXME: Fix BuildMemberReferenceExpr to take a const CXXScopeSpec&. | ||||
328 | CXXScopeSpec SS; | ||||
329 | ExprResult Result = S.BuildMemberReferenceExpr( | ||||
330 | Base, Base->getType(), Loc, /*IsPtr=*/false, SS, | ||||
331 | SourceLocation(), nullptr, NameInfo, /*TemplateArgs=*/nullptr, | ||||
332 | /*Scope=*/nullptr); | ||||
333 | if (Result.isInvalid()) | ||||
334 | return ExprError(); | ||||
335 | |||||
336 | // We meant exactly what we asked for. No need for typo correction. | ||||
337 | if (auto *TE = dyn_cast<TypoExpr>(Result.get())) { | ||||
338 | S.clearDelayedTypo(TE); | ||||
339 | S.Diag(Loc, diag::err_no_member) | ||||
340 | << NameInfo.getName() << Base->getType()->getAsCXXRecordDecl() | ||||
341 | << Base->getSourceRange(); | ||||
342 | return ExprError(); | ||||
343 | } | ||||
344 | |||||
345 | return S.BuildCallExpr(nullptr, Result.get(), Loc, Args, Loc, nullptr); | ||||
346 | } | ||||
347 | |||||
348 | // See if return type is coroutine-handle and if so, invoke builtin coro-resume | ||||
349 | // on its address. This is to enable experimental support for coroutine-handle | ||||
350 | // returning await_suspend that results in a guaranteed tail call to the target | ||||
351 | // coroutine. | ||||
352 | static Expr *maybeTailCall(Sema &S, QualType RetType, Expr *E, | ||||
353 | SourceLocation Loc) { | ||||
354 | if (RetType->isReferenceType()) | ||||
355 | return nullptr; | ||||
356 | Type const *T = RetType.getTypePtr(); | ||||
357 | if (!T->isClassType() && !T->isStructureType()) | ||||
358 | return nullptr; | ||||
359 | |||||
360 | // FIXME: Add convertability check to coroutine_handle<>. Possibly via | ||||
361 | // EvaluateBinaryTypeTrait(BTT_IsConvertible, ...) which is at the moment | ||||
362 | // a private function in SemaExprCXX.cpp | ||||
363 | |||||
364 | ExprResult AddressExpr = buildMemberCall(S, E, Loc, "address", None); | ||||
365 | if (AddressExpr.isInvalid()) | ||||
366 | return nullptr; | ||||
367 | |||||
368 | Expr *JustAddress = AddressExpr.get(); | ||||
369 | |||||
370 | // Check that the type of AddressExpr is void* | ||||
371 | if (!JustAddress->getType().getTypePtr()->isVoidPointerType()) | ||||
372 | S.Diag(cast<CallExpr>(JustAddress)->getCalleeDecl()->getLocation(), | ||||
373 | diag::warn_coroutine_handle_address_invalid_return_type) | ||||
374 | << JustAddress->getType(); | ||||
375 | |||||
376 | // Clean up temporary objects so that they don't live across suspension points | ||||
377 | // unnecessarily. We choose to clean up before the call to | ||||
378 | // __builtin_coro_resume so that the cleanup code are not inserted in-between | ||||
379 | // the resume call and return instruction, which would interfere with the | ||||
380 | // musttail call contract. | ||||
381 | JustAddress = S.MaybeCreateExprWithCleanups(JustAddress); | ||||
382 | return S.BuildBuiltinCallExpr(Loc, Builtin::BI__builtin_coro_resume, | ||||
383 | JustAddress); | ||||
384 | } | ||||
385 | |||||
386 | /// Build calls to await_ready, await_suspend, and await_resume for a co_await | ||||
387 | /// expression. | ||||
388 | /// The generated AST tries to clean up temporary objects as early as | ||||
389 | /// possible so that they don't live across suspension points if possible. | ||||
390 | /// Having temporary objects living across suspension points unnecessarily can | ||||
391 | /// lead to large frame size, and also lead to memory corruptions if the | ||||
392 | /// coroutine frame is destroyed after coming back from suspension. This is done | ||||
393 | /// by wrapping both the await_ready call and the await_suspend call with | ||||
394 | /// ExprWithCleanups. In the end of this function, we also need to explicitly | ||||
395 | /// set cleanup state so that the CoawaitExpr is also wrapped with an | ||||
396 | /// ExprWithCleanups to clean up the awaiter associated with the co_await | ||||
397 | /// expression. | ||||
398 | static ReadySuspendResumeResult buildCoawaitCalls(Sema &S, VarDecl *CoroPromise, | ||||
399 | SourceLocation Loc, Expr *E) { | ||||
400 | OpaqueValueExpr *Operand = new (S.Context) | ||||
401 | OpaqueValueExpr(Loc, E->getType(), VK_LValue, E->getObjectKind(), E); | ||||
402 | |||||
403 | // Assume valid until we see otherwise. | ||||
404 | // Further operations are responsible for setting IsInalid to true. | ||||
405 | ReadySuspendResumeResult Calls = {{}, Operand, /*IsInvalid=*/false}; | ||||
406 | |||||
407 | using ACT = ReadySuspendResumeResult::AwaitCallType; | ||||
408 | |||||
409 | auto BuildSubExpr = [&](ACT CallType, StringRef Func, | ||||
410 | MultiExprArg Arg) -> Expr * { | ||||
411 | ExprResult Result = buildMemberCall(S, Operand, Loc, Func, Arg); | ||||
412 | if (Result.isInvalid()) { | ||||
413 | Calls.IsInvalid = true; | ||||
414 | return nullptr; | ||||
415 | } | ||||
416 | Calls.Results[CallType] = Result.get(); | ||||
417 | return Result.get(); | ||||
418 | }; | ||||
419 | |||||
420 | CallExpr *AwaitReady = | ||||
421 | cast_or_null<CallExpr>(BuildSubExpr(ACT::ACT_Ready, "await_ready", None)); | ||||
422 | if (!AwaitReady) | ||||
423 | return Calls; | ||||
424 | if (!AwaitReady->getType()->isDependentType()) { | ||||
425 | // [expr.await]p3 [...] | ||||
426 | // — await-ready is the expression e.await_ready(), contextually converted | ||||
427 | // to bool. | ||||
428 | ExprResult Conv = S.PerformContextuallyConvertToBool(AwaitReady); | ||||
429 | if (Conv.isInvalid()) { | ||||
430 | S.Diag(AwaitReady->getDirectCallee()->getBeginLoc(), | ||||
431 | diag::note_await_ready_no_bool_conversion); | ||||
432 | S.Diag(Loc, diag::note_coroutine_promise_call_implicitly_required) | ||||
433 | << AwaitReady->getDirectCallee() << E->getSourceRange(); | ||||
434 | Calls.IsInvalid = true; | ||||
435 | } else | ||||
436 | Calls.Results[ACT::ACT_Ready] = S.MaybeCreateExprWithCleanups(Conv.get()); | ||||
437 | } | ||||
438 | |||||
439 | ExprResult CoroHandleRes = | ||||
440 | buildCoroutineHandle(S, CoroPromise->getType(), Loc); | ||||
441 | if (CoroHandleRes.isInvalid()) { | ||||
442 | Calls.IsInvalid = true; | ||||
443 | return Calls; | ||||
444 | } | ||||
445 | Expr *CoroHandle = CoroHandleRes.get(); | ||||
446 | CallExpr *AwaitSuspend = cast_or_null<CallExpr>( | ||||
447 | BuildSubExpr(ACT::ACT_Suspend, "await_suspend", CoroHandle)); | ||||
448 | if (!AwaitSuspend) | ||||
449 | return Calls; | ||||
450 | if (!AwaitSuspend->getType()->isDependentType()) { | ||||
451 | // [expr.await]p3 [...] | ||||
452 | // - await-suspend is the expression e.await_suspend(h), which shall be | ||||
453 | // a prvalue of type void, bool, or std::coroutine_handle<Z> for some | ||||
454 | // type Z. | ||||
455 | QualType RetType = AwaitSuspend->getCallReturnType(S.Context); | ||||
456 | |||||
457 | // Experimental support for coroutine_handle returning await_suspend. | ||||
458 | if (Expr *TailCallSuspend = | ||||
459 | maybeTailCall(S, RetType, AwaitSuspend, Loc)) | ||||
460 | // Note that we don't wrap the expression with ExprWithCleanups here | ||||
461 | // because that might interfere with tailcall contract (e.g. inserting | ||||
462 | // clean up instructions in-between tailcall and return). Instead | ||||
463 | // ExprWithCleanups is wrapped within maybeTailCall() prior to the resume | ||||
464 | // call. | ||||
465 | Calls.Results[ACT::ACT_Suspend] = TailCallSuspend; | ||||
466 | else { | ||||
467 | // non-class prvalues always have cv-unqualified types | ||||
468 | if (RetType->isReferenceType() || | ||||
469 | (!RetType->isBooleanType() && !RetType->isVoidType())) { | ||||
470 | S.Diag(AwaitSuspend->getCalleeDecl()->getLocation(), | ||||
471 | diag::err_await_suspend_invalid_return_type) | ||||
472 | << RetType; | ||||
473 | S.Diag(Loc, diag::note_coroutine_promise_call_implicitly_required) | ||||
474 | << AwaitSuspend->getDirectCallee(); | ||||
475 | Calls.IsInvalid = true; | ||||
476 | } else | ||||
477 | Calls.Results[ACT::ACT_Suspend] = | ||||
478 | S.MaybeCreateExprWithCleanups(AwaitSuspend); | ||||
479 | } | ||||
480 | } | ||||
481 | |||||
482 | BuildSubExpr(ACT::ACT_Resume, "await_resume", None); | ||||
483 | |||||
484 | // Make sure the awaiter object gets a chance to be cleaned up. | ||||
485 | S.Cleanup.setExprNeedsCleanups(true); | ||||
486 | |||||
487 | return Calls; | ||||
488 | } | ||||
489 | |||||
490 | static ExprResult buildPromiseCall(Sema &S, VarDecl *Promise, | ||||
491 | SourceLocation Loc, StringRef Name, | ||||
492 | MultiExprArg Args) { | ||||
493 | |||||
494 | // Form a reference to the promise. | ||||
495 | ExprResult PromiseRef = S.BuildDeclRefExpr( | ||||
496 | Promise, Promise->getType().getNonReferenceType(), VK_LValue, Loc); | ||||
497 | if (PromiseRef.isInvalid()) | ||||
498 | return ExprError(); | ||||
499 | |||||
500 | return buildMemberCall(S, PromiseRef.get(), Loc, Name, Args); | ||||
501 | } | ||||
502 | |||||
503 | VarDecl *Sema::buildCoroutinePromise(SourceLocation Loc) { | ||||
504 | assert(isa<FunctionDecl>(CurContext) && "not in a function scope")(static_cast <bool> (isa<FunctionDecl>(CurContext ) && "not in a function scope") ? void (0) : __assert_fail ("isa<FunctionDecl>(CurContext) && \"not in a function scope\"" , "clang/lib/Sema/SemaCoroutine.cpp", 504, __extension__ __PRETTY_FUNCTION__ )); | ||||
505 | auto *FD = cast<FunctionDecl>(CurContext); | ||||
506 | bool IsThisDependentType = [&] { | ||||
507 | if (auto *MD = dyn_cast_or_null<CXXMethodDecl>(FD)) | ||||
508 | return MD->isInstance() && MD->getThisType()->isDependentType(); | ||||
509 | else | ||||
510 | return false; | ||||
511 | }(); | ||||
512 | |||||
513 | QualType T = FD->getType()->isDependentType() || IsThisDependentType | ||||
514 | ? Context.DependentTy | ||||
515 | : lookupPromiseType(*this, FD, Loc); | ||||
516 | if (T.isNull()) | ||||
517 | return nullptr; | ||||
518 | |||||
519 | auto *VD = VarDecl::Create(Context, FD, FD->getLocation(), FD->getLocation(), | ||||
520 | &PP.getIdentifierTable().get("__promise"), T, | ||||
521 | Context.getTrivialTypeSourceInfo(T, Loc), SC_None); | ||||
522 | VD->setImplicit(); | ||||
523 | CheckVariableDeclarationType(VD); | ||||
524 | if (VD->isInvalidDecl()) | ||||
525 | return nullptr; | ||||
526 | |||||
527 | auto *ScopeInfo = getCurFunction(); | ||||
528 | |||||
529 | // Build a list of arguments, based on the coroutine function's arguments, | ||||
530 | // that if present will be passed to the promise type's constructor. | ||||
531 | llvm::SmallVector<Expr *, 4> CtorArgExprs; | ||||
532 | |||||
533 | // Add implicit object parameter. | ||||
534 | if (auto *MD = dyn_cast<CXXMethodDecl>(FD)) { | ||||
535 | if (MD->isInstance() && !isLambdaCallOperator(MD)) { | ||||
536 | ExprResult ThisExpr = ActOnCXXThis(Loc); | ||||
537 | if (ThisExpr.isInvalid()) | ||||
538 | return nullptr; | ||||
539 | ThisExpr = CreateBuiltinUnaryOp(Loc, UO_Deref, ThisExpr.get()); | ||||
540 | if (ThisExpr.isInvalid()) | ||||
541 | return nullptr; | ||||
542 | CtorArgExprs.push_back(ThisExpr.get()); | ||||
543 | } | ||||
544 | } | ||||
545 | |||||
546 | // Add the coroutine function's parameters. | ||||
547 | auto &Moves = ScopeInfo->CoroutineParameterMoves; | ||||
548 | for (auto *PD : FD->parameters()) { | ||||
549 | if (PD->getType()->isDependentType()) | ||||
550 | continue; | ||||
551 | |||||
552 | auto RefExpr = ExprEmpty(); | ||||
553 | auto Move = Moves.find(PD); | ||||
554 | assert(Move != Moves.end() &&(static_cast <bool> (Move != Moves.end() && "Coroutine function parameter not inserted into move map" ) ? void (0) : __assert_fail ("Move != Moves.end() && \"Coroutine function parameter not inserted into move map\"" , "clang/lib/Sema/SemaCoroutine.cpp", 555, __extension__ __PRETTY_FUNCTION__ )) | ||||
555 | "Coroutine function parameter not inserted into move map")(static_cast <bool> (Move != Moves.end() && "Coroutine function parameter not inserted into move map" ) ? void (0) : __assert_fail ("Move != Moves.end() && \"Coroutine function parameter not inserted into move map\"" , "clang/lib/Sema/SemaCoroutine.cpp", 555, __extension__ __PRETTY_FUNCTION__ )); | ||||
556 | // If a reference to the function parameter exists in the coroutine | ||||
557 | // frame, use that reference. | ||||
558 | auto *MoveDecl = | ||||
559 | cast<VarDecl>(cast<DeclStmt>(Move->second)->getSingleDecl()); | ||||
560 | RefExpr = | ||||
561 | BuildDeclRefExpr(MoveDecl, MoveDecl->getType().getNonReferenceType(), | ||||
562 | ExprValueKind::VK_LValue, FD->getLocation()); | ||||
563 | if (RefExpr.isInvalid()) | ||||
564 | return nullptr; | ||||
565 | CtorArgExprs.push_back(RefExpr.get()); | ||||
566 | } | ||||
567 | |||||
568 | // If we have a non-zero number of constructor arguments, try to use them. | ||||
569 | // Otherwise, fall back to the promise type's default constructor. | ||||
570 | if (!CtorArgExprs.empty()) { | ||||
571 | // Create an initialization sequence for the promise type using the | ||||
572 | // constructor arguments, wrapped in a parenthesized list expression. | ||||
573 | Expr *PLE = ParenListExpr::Create(Context, FD->getLocation(), | ||||
574 | CtorArgExprs, FD->getLocation()); | ||||
575 | InitializedEntity Entity = InitializedEntity::InitializeVariable(VD); | ||||
576 | InitializationKind Kind = InitializationKind::CreateForInit( | ||||
577 | VD->getLocation(), /*DirectInit=*/true, PLE); | ||||
578 | InitializationSequence InitSeq(*this, Entity, Kind, CtorArgExprs, | ||||
579 | /*TopLevelOfInitList=*/false, | ||||
580 | /*TreatUnavailableAsInvalid=*/false); | ||||
581 | |||||
582 | // [dcl.fct.def.coroutine]5.7 | ||||
583 | // promise-constructor-arguments is determined as follows: overload | ||||
584 | // resolution is performed on a promise constructor call created by | ||||
585 | // assembling an argument list q_1 ... q_n . If a viable constructor is | ||||
586 | // found ([over.match.viable]), then promise-constructor-arguments is ( q_1 | ||||
587 | // , ..., q_n ), otherwise promise-constructor-arguments is empty. | ||||
588 | if (InitSeq) { | ||||
589 | ExprResult Result = InitSeq.Perform(*this, Entity, Kind, CtorArgExprs); | ||||
590 | if (Result.isInvalid()) { | ||||
591 | VD->setInvalidDecl(); | ||||
592 | } else if (Result.get()) { | ||||
593 | VD->setInit(MaybeCreateExprWithCleanups(Result.get())); | ||||
594 | VD->setInitStyle(VarDecl::CallInit); | ||||
595 | CheckCompleteVariableDeclaration(VD); | ||||
596 | } | ||||
597 | } else | ||||
598 | ActOnUninitializedDecl(VD); | ||||
599 | } else | ||||
600 | ActOnUninitializedDecl(VD); | ||||
601 | |||||
602 | FD->addDecl(VD); | ||||
603 | return VD; | ||||
604 | } | ||||
605 | |||||
606 | /// Check that this is a context in which a coroutine suspension can appear. | ||||
607 | static FunctionScopeInfo *checkCoroutineContext(Sema &S, SourceLocation Loc, | ||||
608 | StringRef Keyword, | ||||
609 | bool IsImplicit = false) { | ||||
610 | if (!isValidCoroutineContext(S, Loc, Keyword)) | ||||
611 | return nullptr; | ||||
612 | |||||
613 | assert(isa<FunctionDecl>(S.CurContext) && "not in a function scope")(static_cast <bool> (isa<FunctionDecl>(S.CurContext ) && "not in a function scope") ? void (0) : __assert_fail ("isa<FunctionDecl>(S.CurContext) && \"not in a function scope\"" , "clang/lib/Sema/SemaCoroutine.cpp", 613, __extension__ __PRETTY_FUNCTION__ )); | ||||
614 | |||||
615 | auto *ScopeInfo = S.getCurFunction(); | ||||
616 | assert(ScopeInfo && "missing function scope for function")(static_cast <bool> (ScopeInfo && "missing function scope for function" ) ? void (0) : __assert_fail ("ScopeInfo && \"missing function scope for function\"" , "clang/lib/Sema/SemaCoroutine.cpp", 616, __extension__ __PRETTY_FUNCTION__ )); | ||||
617 | |||||
618 | if (ScopeInfo->FirstCoroutineStmtLoc.isInvalid() && !IsImplicit) | ||||
619 | ScopeInfo->setFirstCoroutineStmt(Loc, Keyword); | ||||
620 | |||||
621 | if (ScopeInfo->CoroutinePromise) | ||||
622 | return ScopeInfo; | ||||
623 | |||||
624 | if (!S.buildCoroutineParameterMoves(Loc)) | ||||
625 | return nullptr; | ||||
626 | |||||
627 | ScopeInfo->CoroutinePromise = S.buildCoroutinePromise(Loc); | ||||
628 | if (!ScopeInfo->CoroutinePromise) | ||||
629 | return nullptr; | ||||
630 | |||||
631 | return ScopeInfo; | ||||
632 | } | ||||
633 | |||||
634 | /// Recursively check \p E and all its children to see if any call target | ||||
635 | /// (including constructor call) is declared noexcept. Also any value returned | ||||
636 | /// from the call has a noexcept destructor. | ||||
637 | static void checkNoThrow(Sema &S, const Stmt *E, | ||||
638 | llvm::SmallPtrSetImpl<const Decl *> &ThrowingDecls) { | ||||
639 | auto checkDeclNoexcept = [&](const Decl *D, bool IsDtor = false) { | ||||
640 | // In the case of dtor, the call to dtor is implicit and hence we should | ||||
641 | // pass nullptr to canCalleeThrow. | ||||
642 | if (Sema::canCalleeThrow(S, IsDtor ? nullptr : cast<Expr>(E), D)) { | ||||
643 | if (const auto *FD = dyn_cast<FunctionDecl>(D)) { | ||||
644 | // co_await promise.final_suspend() could end up calling | ||||
645 | // __builtin_coro_resume for symmetric transfer if await_suspend() | ||||
646 | // returns a handle. In that case, even __builtin_coro_resume is not | ||||
647 | // declared as noexcept and may throw, it does not throw _into_ the | ||||
648 | // coroutine that just suspended, but rather throws back out from | ||||
649 | // whoever called coroutine_handle::resume(), hence we claim that | ||||
650 | // logically it does not throw. | ||||
651 | if (FD->getBuiltinID() == Builtin::BI__builtin_coro_resume) | ||||
652 | return; | ||||
653 | } | ||||
654 | if (ThrowingDecls.empty()) { | ||||
655 | // [dcl.fct.def.coroutine]p15 | ||||
656 | // The expression co_await promise.final_suspend() shall not be | ||||
657 | // potentially-throwing ([except.spec]). | ||||
658 | // | ||||
659 | // First time seeing an error, emit the error message. | ||||
660 | S.Diag(cast<FunctionDecl>(S.CurContext)->getLocation(), | ||||
661 | diag::err_coroutine_promise_final_suspend_requires_nothrow); | ||||
662 | } | ||||
663 | ThrowingDecls.insert(D); | ||||
664 | } | ||||
665 | }; | ||||
666 | |||||
667 | if (auto *CE
| ||||
668 | CXXConstructorDecl *Ctor = CE->getConstructor(); | ||||
669 | checkDeclNoexcept(Ctor); | ||||
670 | // Check the corresponding destructor of the constructor. | ||||
671 | checkDeclNoexcept(Ctor->getParent()->getDestructor(), /*IsDtor=*/true); | ||||
672 | } else if (auto *CE
| ||||
673 | if (CE->isTypeDependent()) | ||||
674 | return; | ||||
675 | |||||
676 | checkDeclNoexcept(CE->getCalleeDecl()); | ||||
677 | QualType ReturnType = CE->getCallReturnType(S.getASTContext()); | ||||
678 | // Check the destructor of the call return type, if any. | ||||
679 | if (ReturnType.isDestructedType() == | ||||
680 | QualType::DestructionKind::DK_cxx_destructor) { | ||||
681 | const auto *T = | ||||
682 | cast<RecordType>(ReturnType.getCanonicalType().getTypePtr()); | ||||
683 | checkDeclNoexcept(dyn_cast<CXXRecordDecl>(T->getDecl())->getDestructor(), | ||||
| |||||
684 | /*IsDtor=*/true); | ||||
685 | } | ||||
686 | } else | ||||
687 | for (const auto *Child : E->children()) { | ||||
688 | if (!Child) | ||||
689 | continue; | ||||
690 | checkNoThrow(S, Child, ThrowingDecls); | ||||
691 | } | ||||
692 | } | ||||
693 | |||||
694 | bool Sema::checkFinalSuspendNoThrow(const Stmt *FinalSuspend) { | ||||
695 | llvm::SmallPtrSet<const Decl *, 4> ThrowingDecls; | ||||
696 | // We first collect all declarations that should not throw but not declared | ||||
697 | // with noexcept. We then sort them based on the location before printing. | ||||
698 | // This is to avoid emitting the same note multiple times on the same | ||||
699 | // declaration, and also provide a deterministic order for the messages. | ||||
700 | checkNoThrow(*this, FinalSuspend, ThrowingDecls); | ||||
701 | auto SortedDecls = llvm::SmallVector<const Decl *, 4>{ThrowingDecls.begin(), | ||||
702 | ThrowingDecls.end()}; | ||||
703 | sort(SortedDecls, [](const Decl *A, const Decl *B) { | ||||
704 | return A->getEndLoc() < B->getEndLoc(); | ||||
705 | }); | ||||
706 | for (const auto *D : SortedDecls) { | ||||
707 | Diag(D->getEndLoc(), diag::note_coroutine_function_declare_noexcept); | ||||
708 | } | ||||
709 | return ThrowingDecls.empty(); | ||||
710 | } | ||||
711 | |||||
712 | bool Sema::ActOnCoroutineBodyStart(Scope *SC, SourceLocation KWLoc, | ||||
713 | StringRef Keyword) { | ||||
714 | if (!checkCoroutineContext(*this, KWLoc, Keyword)) | ||||
715 | return false; | ||||
716 | auto *ScopeInfo = getCurFunction(); | ||||
717 | assert(ScopeInfo->CoroutinePromise)(static_cast <bool> (ScopeInfo->CoroutinePromise) ? void (0) : __assert_fail ("ScopeInfo->CoroutinePromise", "clang/lib/Sema/SemaCoroutine.cpp" , 717, __extension__ __PRETTY_FUNCTION__)); | ||||
718 | |||||
719 | // If we have existing coroutine statements then we have already built | ||||
720 | // the initial and final suspend points. | ||||
721 | if (!ScopeInfo->NeedsCoroutineSuspends) | ||||
722 | return true; | ||||
723 | |||||
724 | ScopeInfo->setNeedsCoroutineSuspends(false); | ||||
725 | |||||
726 | auto *Fn = cast<FunctionDecl>(CurContext); | ||||
727 | SourceLocation Loc = Fn->getLocation(); | ||||
728 | // Build the initial suspend point | ||||
729 | auto buildSuspends = [&](StringRef Name) mutable -> StmtResult { | ||||
730 | ExprResult Suspend = | ||||
731 | buildPromiseCall(*this, ScopeInfo->CoroutinePromise, Loc, Name, None); | ||||
732 | if (Suspend.isInvalid()) | ||||
733 | return StmtError(); | ||||
734 | Suspend = buildOperatorCoawaitCall(*this, SC, Loc, Suspend.get()); | ||||
735 | if (Suspend.isInvalid()) | ||||
736 | return StmtError(); | ||||
737 | Suspend = BuildResolvedCoawaitExpr(Loc, Suspend.get(), | ||||
738 | /*IsImplicit*/ true); | ||||
739 | Suspend = ActOnFinishFullExpr(Suspend.get(), /*DiscardedValue*/ false); | ||||
740 | if (Suspend.isInvalid()) { | ||||
741 | Diag(Loc, diag::note_coroutine_promise_suspend_implicitly_required) | ||||
742 | << ((Name == "initial_suspend") ? 0 : 1); | ||||
743 | Diag(KWLoc, diag::note_declared_coroutine_here) << Keyword; | ||||
744 | return StmtError(); | ||||
745 | } | ||||
746 | return cast<Stmt>(Suspend.get()); | ||||
747 | }; | ||||
748 | |||||
749 | StmtResult InitSuspend = buildSuspends("initial_suspend"); | ||||
750 | if (InitSuspend.isInvalid()) | ||||
751 | return true; | ||||
752 | |||||
753 | StmtResult FinalSuspend = buildSuspends("final_suspend"); | ||||
754 | if (FinalSuspend.isInvalid() || !checkFinalSuspendNoThrow(FinalSuspend.get())) | ||||
755 | return true; | ||||
756 | |||||
757 | ScopeInfo->setCoroutineSuspends(InitSuspend.get(), FinalSuspend.get()); | ||||
758 | |||||
759 | return true; | ||||
760 | } | ||||
761 | |||||
762 | // Recursively walks up the scope hierarchy until either a 'catch' or a function | ||||
763 | // scope is found, whichever comes first. | ||||
764 | static bool isWithinCatchScope(Scope *S) { | ||||
765 | // 'co_await' and 'co_yield' keywords are disallowed within catch blocks, but | ||||
766 | // lambdas that use 'co_await' are allowed. The loop below ends when a | ||||
767 | // function scope is found in order to ensure the following behavior: | ||||
768 | // | ||||
769 | // void foo() { // <- function scope | ||||
770 | // try { // | ||||
771 | // co_await x; // <- 'co_await' is OK within a function scope | ||||
772 | // } catch { // <- catch scope | ||||
773 | // co_await x; // <- 'co_await' is not OK within a catch scope | ||||
774 | // []() { // <- function scope | ||||
775 | // co_await x; // <- 'co_await' is OK within a function scope | ||||
776 | // }(); | ||||
777 | // } | ||||
778 | // } | ||||
779 | while (S && !(S->getFlags() & Scope::FnScope)) { | ||||
780 | if (S->getFlags() & Scope::CatchScope) | ||||
781 | return true; | ||||
782 | S = S->getParent(); | ||||
783 | } | ||||
784 | return false; | ||||
785 | } | ||||
786 | |||||
787 | // [expr.await]p2, emphasis added: "An await-expression shall appear only in | ||||
788 | // a *potentially evaluated* expression within the compound-statement of a | ||||
789 | // function-body *outside of a handler* [...] A context within a function | ||||
790 | // where an await-expression can appear is called a suspension context of the | ||||
791 | // function." | ||||
792 | static void checkSuspensionContext(Sema &S, SourceLocation Loc, | ||||
793 | StringRef Keyword) { | ||||
794 | // First emphasis of [expr.await]p2: must be a potentially evaluated context. | ||||
795 | // That is, 'co_await' and 'co_yield' cannot appear in subexpressions of | ||||
796 | // \c sizeof. | ||||
797 | if (S.isUnevaluatedContext()) | ||||
798 | S.Diag(Loc, diag::err_coroutine_unevaluated_context) << Keyword; | ||||
799 | |||||
800 | // Second emphasis of [expr.await]p2: must be outside of an exception handler. | ||||
801 | if (isWithinCatchScope(S.getCurScope())) | ||||
802 | S.Diag(Loc, diag::err_coroutine_within_handler) << Keyword; | ||||
803 | } | ||||
804 | |||||
805 | ExprResult Sema::ActOnCoawaitExpr(Scope *S, SourceLocation Loc, Expr *E) { | ||||
806 | if (!ActOnCoroutineBodyStart(S, Loc, "co_await")) { | ||||
807 | CorrectDelayedTyposInExpr(E); | ||||
808 | return ExprError(); | ||||
809 | } | ||||
810 | |||||
811 | checkSuspensionContext(*this, Loc, "co_await"); | ||||
812 | |||||
813 | if (E->hasPlaceholderType()) { | ||||
814 | ExprResult R = CheckPlaceholderExpr(E); | ||||
815 | if (R.isInvalid()) return ExprError(); | ||||
816 | E = R.get(); | ||||
817 | } | ||||
818 | ExprResult Lookup = buildOperatorCoawaitLookupExpr(*this, S, Loc); | ||||
819 | if (Lookup.isInvalid()) | ||||
820 | return ExprError(); | ||||
821 | return BuildUnresolvedCoawaitExpr(Loc, E, | ||||
822 | cast<UnresolvedLookupExpr>(Lookup.get())); | ||||
823 | } | ||||
824 | |||||
825 | ExprResult Sema::BuildUnresolvedCoawaitExpr(SourceLocation Loc, Expr *E, | ||||
826 | UnresolvedLookupExpr *Lookup) { | ||||
827 | auto *FSI = checkCoroutineContext(*this, Loc, "co_await"); | ||||
828 | if (!FSI) | ||||
829 | return ExprError(); | ||||
830 | |||||
831 | if (E->hasPlaceholderType()) { | ||||
832 | ExprResult R = CheckPlaceholderExpr(E); | ||||
833 | if (R.isInvalid()) | ||||
834 | return ExprError(); | ||||
835 | E = R.get(); | ||||
836 | } | ||||
837 | |||||
838 | auto *Promise = FSI->CoroutinePromise; | ||||
839 | if (Promise->getType()->isDependentType()) { | ||||
840 | Expr *Res = | ||||
841 | new (Context) DependentCoawaitExpr(Loc, Context.DependentTy, E, Lookup); | ||||
842 | return Res; | ||||
843 | } | ||||
844 | |||||
845 | auto *RD = Promise->getType()->getAsCXXRecordDecl(); | ||||
846 | if (lookupMember(*this, "await_transform", RD, Loc)) { | ||||
847 | ExprResult R = buildPromiseCall(*this, Promise, Loc, "await_transform", E); | ||||
848 | if (R.isInvalid()) { | ||||
849 | Diag(Loc, | ||||
850 | diag::note_coroutine_promise_implicit_await_transform_required_here) | ||||
851 | << E->getSourceRange(); | ||||
852 | return ExprError(); | ||||
853 | } | ||||
854 | E = R.get(); | ||||
855 | } | ||||
856 | ExprResult Awaitable = buildOperatorCoawaitCall(*this, Loc, E, Lookup); | ||||
857 | if (Awaitable.isInvalid()) | ||||
858 | return ExprError(); | ||||
859 | |||||
860 | return BuildResolvedCoawaitExpr(Loc, Awaitable.get()); | ||||
861 | } | ||||
862 | |||||
863 | ExprResult Sema::BuildResolvedCoawaitExpr(SourceLocation Loc, Expr *E, | ||||
864 | bool IsImplicit) { | ||||
865 | auto *Coroutine = checkCoroutineContext(*this, Loc, "co_await", IsImplicit); | ||||
866 | if (!Coroutine) | ||||
867 | return ExprError(); | ||||
868 | |||||
869 | if (E->hasPlaceholderType()) { | ||||
870 | ExprResult R = CheckPlaceholderExpr(E); | ||||
871 | if (R.isInvalid()) return ExprError(); | ||||
872 | E = R.get(); | ||||
873 | } | ||||
874 | |||||
875 | if (E->getType()->isDependentType()) { | ||||
876 | Expr *Res = new (Context) | ||||
877 | CoawaitExpr(Loc, Context.DependentTy, E, IsImplicit); | ||||
878 | return Res; | ||||
879 | } | ||||
880 | |||||
881 | // If the expression is a temporary, materialize it as an lvalue so that we | ||||
882 | // can use it multiple times. | ||||
883 | if (E->isPRValue()) | ||||
884 | E = CreateMaterializeTemporaryExpr(E->getType(), E, true); | ||||
885 | |||||
886 | // The location of the `co_await` token cannot be used when constructing | ||||
887 | // the member call expressions since it's before the location of `Expr`, which | ||||
888 | // is used as the start of the member call expression. | ||||
889 | SourceLocation CallLoc = E->getExprLoc(); | ||||
890 | |||||
891 | // Build the await_ready, await_suspend, await_resume calls. | ||||
892 | ReadySuspendResumeResult RSS = buildCoawaitCalls( | ||||
893 | *this, Coroutine->CoroutinePromise, CallLoc, E); | ||||
894 | if (RSS.IsInvalid) | ||||
895 | return ExprError(); | ||||
896 | |||||
897 | Expr *Res = | ||||
898 | new (Context) CoawaitExpr(Loc, E, RSS.Results[0], RSS.Results[1], | ||||
899 | RSS.Results[2], RSS.OpaqueValue, IsImplicit); | ||||
900 | |||||
901 | return Res; | ||||
902 | } | ||||
903 | |||||
904 | ExprResult Sema::ActOnCoyieldExpr(Scope *S, SourceLocation Loc, Expr *E) { | ||||
905 | if (!ActOnCoroutineBodyStart(S, Loc, "co_yield")) { | ||||
906 | CorrectDelayedTyposInExpr(E); | ||||
907 | return ExprError(); | ||||
908 | } | ||||
909 | |||||
910 | checkSuspensionContext(*this, Loc, "co_yield"); | ||||
911 | |||||
912 | // Build yield_value call. | ||||
913 | ExprResult Awaitable = buildPromiseCall( | ||||
914 | *this, getCurFunction()->CoroutinePromise, Loc, "yield_value", E); | ||||
915 | if (Awaitable.isInvalid()) | ||||
916 | return ExprError(); | ||||
917 | |||||
918 | // Build 'operator co_await' call. | ||||
919 | Awaitable = buildOperatorCoawaitCall(*this, S, Loc, Awaitable.get()); | ||||
920 | if (Awaitable.isInvalid()) | ||||
921 | return ExprError(); | ||||
922 | |||||
923 | return BuildCoyieldExpr(Loc, Awaitable.get()); | ||||
924 | } | ||||
925 | ExprResult Sema::BuildCoyieldExpr(SourceLocation Loc, Expr *E) { | ||||
926 | auto *Coroutine = checkCoroutineContext(*this, Loc, "co_yield"); | ||||
927 | if (!Coroutine) | ||||
928 | return ExprError(); | ||||
929 | |||||
930 | if (E->hasPlaceholderType()) { | ||||
931 | ExprResult R = CheckPlaceholderExpr(E); | ||||
932 | if (R.isInvalid()) return ExprError(); | ||||
933 | E = R.get(); | ||||
934 | } | ||||
935 | |||||
936 | if (E->getType()->isDependentType()) { | ||||
937 | Expr *Res = new (Context) CoyieldExpr(Loc, Context.DependentTy, E); | ||||
938 | return Res; | ||||
939 | } | ||||
940 | |||||
941 | // If the expression is a temporary, materialize it as an lvalue so that we | ||||
942 | // can use it multiple times. | ||||
943 | if (E->isPRValue()) | ||||
944 | E = CreateMaterializeTemporaryExpr(E->getType(), E, true); | ||||
945 | |||||
946 | // Build the await_ready, await_suspend, await_resume calls. | ||||
947 | ReadySuspendResumeResult RSS = buildCoawaitCalls( | ||||
948 | *this, Coroutine->CoroutinePromise, Loc, E); | ||||
949 | if (RSS.IsInvalid) | ||||
950 | return ExprError(); | ||||
951 | |||||
952 | Expr *Res = | ||||
953 | new (Context) CoyieldExpr(Loc, E, RSS.Results[0], RSS.Results[1], | ||||
954 | RSS.Results[2], RSS.OpaqueValue); | ||||
955 | |||||
956 | return Res; | ||||
957 | } | ||||
958 | |||||
959 | StmtResult Sema::ActOnCoreturnStmt(Scope *S, SourceLocation Loc, Expr *E) { | ||||
960 | if (!ActOnCoroutineBodyStart(S, Loc, "co_return")) { | ||||
| |||||
961 | CorrectDelayedTyposInExpr(E); | ||||
962 | return StmtError(); | ||||
963 | } | ||||
964 | return BuildCoreturnStmt(Loc, E); | ||||
965 | } | ||||
966 | |||||
967 | StmtResult Sema::BuildCoreturnStmt(SourceLocation Loc, Expr *E, | ||||
968 | bool IsImplicit) { | ||||
969 | auto *FSI = checkCoroutineContext(*this, Loc, "co_return", IsImplicit); | ||||
970 | if (!FSI) | ||||
971 | return StmtError(); | ||||
972 | |||||
973 | if (E && E->hasPlaceholderType() && | ||||
974 | !E->hasPlaceholderType(BuiltinType::Overload)) { | ||||
975 | ExprResult R = CheckPlaceholderExpr(E); | ||||
976 | if (R.isInvalid()) return StmtError(); | ||||
977 | E = R.get(); | ||||
978 | } | ||||
979 | |||||
980 | VarDecl *Promise = FSI->CoroutinePromise; | ||||
981 | ExprResult PC; | ||||
982 | if (E && (isa<InitListExpr>(E) || !E->getType()->isVoidType())) { | ||||
983 | getNamedReturnInfo(E, SimplerImplicitMoveMode::ForceOn); | ||||
984 | PC = buildPromiseCall(*this, Promise, Loc, "return_value", E); | ||||
985 | } else { | ||||
986 | E = MakeFullDiscardedValueExpr(E).get(); | ||||
987 | PC = buildPromiseCall(*this, Promise, Loc, "return_void", None); | ||||
988 | } | ||||
989 | if (PC.isInvalid()) | ||||
990 | return StmtError(); | ||||
991 | |||||
992 | Expr *PCE = ActOnFinishFullExpr(PC.get(), /*DiscardedValue*/ false).get(); | ||||
993 | |||||
994 | Stmt *Res = new (Context) CoreturnStmt(Loc, E, PCE, IsImplicit); | ||||
995 | return Res; | ||||
996 | } | ||||
997 | |||||
998 | /// Look up the std::nothrow object. | ||||
999 | static Expr *buildStdNoThrowDeclRef(Sema &S, SourceLocation Loc) { | ||||
1000 | NamespaceDecl *Std = S.getStdNamespace(); | ||||
1001 | assert(Std && "Should already be diagnosed")(static_cast <bool> (Std && "Should already be diagnosed" ) ? void (0) : __assert_fail ("Std && \"Should already be diagnosed\"" , "clang/lib/Sema/SemaCoroutine.cpp", 1001, __extension__ __PRETTY_FUNCTION__ )); | ||||
1002 | |||||
1003 | LookupResult Result(S, &S.PP.getIdentifierTable().get("nothrow"), Loc, | ||||
1004 | Sema::LookupOrdinaryName); | ||||
1005 | if (!S.LookupQualifiedName(Result, Std)) { | ||||
1006 | // <coroutine> is not requred to include <new>, so we couldn't omit | ||||
1007 | // the check here. | ||||
1008 | S.Diag(Loc, diag::err_implicit_coroutine_std_nothrow_type_not_found); | ||||
1009 | return nullptr; | ||||
1010 | } | ||||
1011 | |||||
1012 | auto *VD = Result.getAsSingle<VarDecl>(); | ||||
1013 | if (!VD) { | ||||
1014 | Result.suppressDiagnostics(); | ||||
1015 | // We found something weird. Complain about the first thing we found. | ||||
1016 | NamedDecl *Found = *Result.begin(); | ||||
1017 | S.Diag(Found->getLocation(), diag::err_malformed_std_nothrow); | ||||
1018 | return nullptr; | ||||
1019 | } | ||||
1020 | |||||
1021 | ExprResult DR = S.BuildDeclRefExpr(VD, VD->getType(), VK_LValue, Loc); | ||||
1022 | if (DR.isInvalid()) | ||||
1023 | return nullptr; | ||||
1024 | |||||
1025 | return DR.get(); | ||||
1026 | } | ||||
1027 | |||||
1028 | // Find an appropriate delete for the promise. | ||||
1029 | static FunctionDecl *findDeleteForPromise(Sema &S, SourceLocation Loc, | ||||
1030 | QualType PromiseType) { | ||||
1031 | FunctionDecl *OperatorDelete = nullptr; | ||||
1032 | |||||
1033 | DeclarationName DeleteName = | ||||
1034 | S.Context.DeclarationNames.getCXXOperatorName(OO_Delete); | ||||
1035 | |||||
1036 | auto *PointeeRD = PromiseType->getAsCXXRecordDecl(); | ||||
1037 | assert(PointeeRD && "PromiseType must be a CxxRecordDecl type")(static_cast <bool> (PointeeRD && "PromiseType must be a CxxRecordDecl type" ) ? void (0) : __assert_fail ("PointeeRD && \"PromiseType must be a CxxRecordDecl type\"" , "clang/lib/Sema/SemaCoroutine.cpp", 1037, __extension__ __PRETTY_FUNCTION__ )); | ||||
1038 | |||||
1039 | // [dcl.fct.def.coroutine]p12 | ||||
1040 | // The deallocation function's name is looked up by searching for it in the | ||||
1041 | // scope of the promise type. If nothing is found, a search is performed in | ||||
1042 | // the global scope. | ||||
1043 | if (S.FindDeallocationFunction(Loc, PointeeRD, DeleteName, OperatorDelete)) | ||||
1044 | return nullptr; | ||||
1045 | |||||
1046 | // FIXME: We didn't implement following selection: | ||||
1047 | // [dcl.fct.def.coroutine]p12 | ||||
1048 | // If both a usual deallocation function with only a pointer parameter and a | ||||
1049 | // usual deallocation function with both a pointer parameter and a size | ||||
1050 | // parameter are found, then the selected deallocation function shall be the | ||||
1051 | // one with two parameters. Otherwise, the selected deallocation function | ||||
1052 | // shall be the function with one parameter. | ||||
1053 | |||||
1054 | if (!OperatorDelete) { | ||||
1055 | // Look for a global declaration. | ||||
1056 | const bool CanProvideSize = S.isCompleteType(Loc, PromiseType); | ||||
1057 | const bool Overaligned = false; | ||||
1058 | OperatorDelete = S.FindUsualDeallocationFunction(Loc, CanProvideSize, | ||||
1059 | Overaligned, DeleteName); | ||||
1060 | } | ||||
1061 | S.MarkFunctionReferenced(Loc, OperatorDelete); | ||||
1062 | return OperatorDelete; | ||||
1063 | } | ||||
1064 | |||||
1065 | |||||
1066 | void Sema::CheckCompletedCoroutineBody(FunctionDecl *FD, Stmt *&Body) { | ||||
1067 | FunctionScopeInfo *Fn = getCurFunction(); | ||||
1068 | assert(Fn && Fn->isCoroutine() && "not a coroutine")(static_cast <bool> (Fn && Fn->isCoroutine() && "not a coroutine") ? void (0) : __assert_fail ("Fn && Fn->isCoroutine() && \"not a coroutine\"" , "clang/lib/Sema/SemaCoroutine.cpp", 1068, __extension__ __PRETTY_FUNCTION__ )); | ||||
1069 | if (!Body) { | ||||
1070 | assert(FD->isInvalidDecl() &&(static_cast <bool> (FD->isInvalidDecl() && "a null body is only allowed for invalid declarations" ) ? void (0) : __assert_fail ("FD->isInvalidDecl() && \"a null body is only allowed for invalid declarations\"" , "clang/lib/Sema/SemaCoroutine.cpp", 1071, __extension__ __PRETTY_FUNCTION__ )) | ||||
1071 | "a null body is only allowed for invalid declarations")(static_cast <bool> (FD->isInvalidDecl() && "a null body is only allowed for invalid declarations" ) ? void (0) : __assert_fail ("FD->isInvalidDecl() && \"a null body is only allowed for invalid declarations\"" , "clang/lib/Sema/SemaCoroutine.cpp", 1071, __extension__ __PRETTY_FUNCTION__ )); | ||||
1072 | return; | ||||
1073 | } | ||||
1074 | // We have a function that uses coroutine keywords, but we failed to build | ||||
1075 | // the promise type. | ||||
1076 | if (!Fn->CoroutinePromise) | ||||
1077 | return FD->setInvalidDecl(); | ||||
1078 | |||||
1079 | if (isa<CoroutineBodyStmt>(Body)) { | ||||
1080 | // Nothing todo. the body is already a transformed coroutine body statement. | ||||
1081 | return; | ||||
1082 | } | ||||
1083 | |||||
1084 | // The always_inline attribute doesn't reliably apply to a coroutine, | ||||
1085 | // because the coroutine will be split into pieces and some pieces | ||||
1086 | // might be called indirectly, as in a virtual call. Even the ramp | ||||
1087 | // function cannot be inlined at -O0, due to pipeline ordering | ||||
1088 | // problems (see https://llvm.org/PR53413). Tell the user about it. | ||||
1089 | if (FD->hasAttr<AlwaysInlineAttr>()) | ||||
1090 | Diag(FD->getLocation(), diag::warn_always_inline_coroutine); | ||||
1091 | |||||
1092 | // [stmt.return.coroutine]p1: | ||||
1093 | // A coroutine shall not enclose a return statement ([stmt.return]). | ||||
1094 | if (Fn->FirstReturnLoc.isValid()) { | ||||
1095 | assert(Fn->FirstCoroutineStmtLoc.isValid() &&(static_cast <bool> (Fn->FirstCoroutineStmtLoc.isValid () && "first coroutine location not set") ? void (0) : __assert_fail ("Fn->FirstCoroutineStmtLoc.isValid() && \"first coroutine location not set\"" , "clang/lib/Sema/SemaCoroutine.cpp", 1096, __extension__ __PRETTY_FUNCTION__ )) | ||||
1096 | "first coroutine location not set")(static_cast <bool> (Fn->FirstCoroutineStmtLoc.isValid () && "first coroutine location not set") ? void (0) : __assert_fail ("Fn->FirstCoroutineStmtLoc.isValid() && \"first coroutine location not set\"" , "clang/lib/Sema/SemaCoroutine.cpp", 1096, __extension__ __PRETTY_FUNCTION__ )); | ||||
1097 | Diag(Fn->FirstReturnLoc, diag::err_return_in_coroutine); | ||||
1098 | Diag(Fn->FirstCoroutineStmtLoc, diag::note_declared_coroutine_here) | ||||
1099 | << Fn->getFirstCoroutineStmtKeyword(); | ||||
1100 | } | ||||
1101 | CoroutineStmtBuilder Builder(*this, *FD, *Fn, Body); | ||||
1102 | if (Builder.isInvalid() || !Builder.buildStatements()) | ||||
1103 | return FD->setInvalidDecl(); | ||||
1104 | |||||
1105 | // Build body for the coroutine wrapper statement. | ||||
1106 | Body = CoroutineBodyStmt::Create(Context, Builder); | ||||
1107 | } | ||||
1108 | |||||
1109 | CoroutineStmtBuilder::CoroutineStmtBuilder(Sema &S, FunctionDecl &FD, | ||||
1110 | sema::FunctionScopeInfo &Fn, | ||||
1111 | Stmt *Body) | ||||
1112 | : S(S), FD(FD), Fn(Fn), Loc(FD.getLocation()), | ||||
1113 | IsPromiseDependentType( | ||||
1114 | !Fn.CoroutinePromise || | ||||
1115 | Fn.CoroutinePromise->getType()->isDependentType()) { | ||||
1116 | this->Body = Body; | ||||
1117 | |||||
1118 | for (auto KV : Fn.CoroutineParameterMoves) | ||||
1119 | this->ParamMovesVector.push_back(KV.second); | ||||
1120 | this->ParamMoves = this->ParamMovesVector; | ||||
1121 | |||||
1122 | if (!IsPromiseDependentType) { | ||||
1123 | PromiseRecordDecl = Fn.CoroutinePromise->getType()->getAsCXXRecordDecl(); | ||||
1124 | assert(PromiseRecordDecl && "Type should have already been checked")(static_cast <bool> (PromiseRecordDecl && "Type should have already been checked" ) ? void (0) : __assert_fail ("PromiseRecordDecl && \"Type should have already been checked\"" , "clang/lib/Sema/SemaCoroutine.cpp", 1124, __extension__ __PRETTY_FUNCTION__ )); | ||||
1125 | } | ||||
1126 | this->IsValid = makePromiseStmt() && makeInitialAndFinalSuspend(); | ||||
1127 | } | ||||
1128 | |||||
1129 | bool CoroutineStmtBuilder::buildStatements() { | ||||
1130 | assert(this->IsValid && "coroutine already invalid")(static_cast <bool> (this->IsValid && "coroutine already invalid" ) ? void (0) : __assert_fail ("this->IsValid && \"coroutine already invalid\"" , "clang/lib/Sema/SemaCoroutine.cpp", 1130, __extension__ __PRETTY_FUNCTION__ )); | ||||
1131 | this->IsValid = makeReturnObject(); | ||||
1132 | if (this->IsValid && !IsPromiseDependentType) | ||||
1133 | buildDependentStatements(); | ||||
1134 | return this->IsValid; | ||||
1135 | } | ||||
1136 | |||||
1137 | bool CoroutineStmtBuilder::buildDependentStatements() { | ||||
1138 | assert(this->IsValid && "coroutine already invalid")(static_cast <bool> (this->IsValid && "coroutine already invalid" ) ? void (0) : __assert_fail ("this->IsValid && \"coroutine already invalid\"" , "clang/lib/Sema/SemaCoroutine.cpp", 1138, __extension__ __PRETTY_FUNCTION__ )); | ||||
1139 | assert(!this->IsPromiseDependentType &&(static_cast <bool> (!this->IsPromiseDependentType && "coroutine cannot have a dependent promise type") ? void (0) : __assert_fail ("!this->IsPromiseDependentType && \"coroutine cannot have a dependent promise type\"" , "clang/lib/Sema/SemaCoroutine.cpp", 1140, __extension__ __PRETTY_FUNCTION__ )) | ||||
1140 | "coroutine cannot have a dependent promise type")(static_cast <bool> (!this->IsPromiseDependentType && "coroutine cannot have a dependent promise type") ? void (0) : __assert_fail ("!this->IsPromiseDependentType && \"coroutine cannot have a dependent promise type\"" , "clang/lib/Sema/SemaCoroutine.cpp", 1140, __extension__ __PRETTY_FUNCTION__ )); | ||||
1141 | this->IsValid = makeOnException() && makeOnFallthrough() && | ||||
1142 | makeGroDeclAndReturnStmt() && makeReturnOnAllocFailure() && | ||||
1143 | makeNewAndDeleteExpr(); | ||||
1144 | return this->IsValid; | ||||
1145 | } | ||||
1146 | |||||
1147 | bool CoroutineStmtBuilder::makePromiseStmt() { | ||||
1148 | // Form a declaration statement for the promise declaration, so that AST | ||||
1149 | // visitors can more easily find it. | ||||
1150 | StmtResult PromiseStmt = | ||||
1151 | S.ActOnDeclStmt(S.ConvertDeclToDeclGroup(Fn.CoroutinePromise), Loc, Loc); | ||||
1152 | if (PromiseStmt.isInvalid()) | ||||
1153 | return false; | ||||
1154 | |||||
1155 | this->Promise = PromiseStmt.get(); | ||||
1156 | return true; | ||||
1157 | } | ||||
1158 | |||||
1159 | bool CoroutineStmtBuilder::makeInitialAndFinalSuspend() { | ||||
1160 | if (Fn.hasInvalidCoroutineSuspends()) | ||||
1161 | return false; | ||||
1162 | this->InitialSuspend = cast<Expr>(Fn.CoroutineSuspends.first); | ||||
1163 | this->FinalSuspend = cast<Expr>(Fn.CoroutineSuspends.second); | ||||
1164 | return true; | ||||
1165 | } | ||||
1166 | |||||
1167 | static bool diagReturnOnAllocFailure(Sema &S, Expr *E, | ||||
1168 | CXXRecordDecl *PromiseRecordDecl, | ||||
1169 | FunctionScopeInfo &Fn) { | ||||
1170 | auto Loc = E->getExprLoc(); | ||||
1171 | if (auto *DeclRef = dyn_cast_or_null<DeclRefExpr>(E)) { | ||||
1172 | auto *Decl = DeclRef->getDecl(); | ||||
1173 | if (CXXMethodDecl *Method = dyn_cast_or_null<CXXMethodDecl>(Decl)) { | ||||
1174 | if (Method->isStatic()) | ||||
1175 | return true; | ||||
1176 | else | ||||
1177 | Loc = Decl->getLocation(); | ||||
1178 | } | ||||
1179 | } | ||||
1180 | |||||
1181 | S.Diag( | ||||
1182 | Loc, | ||||
1183 | diag::err_coroutine_promise_get_return_object_on_allocation_failure) | ||||
1184 | << PromiseRecordDecl; | ||||
1185 | S.Diag(Fn.FirstCoroutineStmtLoc, diag::note_declared_coroutine_here) | ||||
1186 | << Fn.getFirstCoroutineStmtKeyword(); | ||||
1187 | return false; | ||||
1188 | } | ||||
1189 | |||||
1190 | bool CoroutineStmtBuilder::makeReturnOnAllocFailure() { | ||||
1191 | assert(!IsPromiseDependentType &&(static_cast <bool> (!IsPromiseDependentType && "cannot make statement while the promise type is dependent") ? void (0) : __assert_fail ("!IsPromiseDependentType && \"cannot make statement while the promise type is dependent\"" , "clang/lib/Sema/SemaCoroutine.cpp", 1192, __extension__ __PRETTY_FUNCTION__ )) | ||||
1192 | "cannot make statement while the promise type is dependent")(static_cast <bool> (!IsPromiseDependentType && "cannot make statement while the promise type is dependent") ? void (0) : __assert_fail ("!IsPromiseDependentType && \"cannot make statement while the promise type is dependent\"" , "clang/lib/Sema/SemaCoroutine.cpp", 1192, __extension__ __PRETTY_FUNCTION__ )); | ||||
1193 | |||||
1194 | // [dcl.fct.def.coroutine]p10 | ||||
1195 | // If a search for the name get_return_object_on_allocation_failure in | ||||
1196 | // the scope of the promise type ([class.member.lookup]) finds any | ||||
1197 | // declarations, then the result of a call to an allocation function used to | ||||
1198 | // obtain storage for the coroutine state is assumed to return nullptr if it | ||||
1199 | // fails to obtain storage, ... If the allocation function returns nullptr, | ||||
1200 | // ... and the return value is obtained by a call to | ||||
1201 | // T::get_return_object_on_allocation_failure(), where T is the | ||||
1202 | // promise type. | ||||
1203 | DeclarationName DN = | ||||
1204 | S.PP.getIdentifierInfo("get_return_object_on_allocation_failure"); | ||||
1205 | LookupResult Found(S, DN, Loc, Sema::LookupMemberName); | ||||
1206 | if (!S.LookupQualifiedName(Found, PromiseRecordDecl)) | ||||
1207 | return true; | ||||
1208 | |||||
1209 | CXXScopeSpec SS; | ||||
1210 | ExprResult DeclNameExpr = | ||||
1211 | S.BuildDeclarationNameExpr(SS, Found, /*NeedsADL=*/false); | ||||
1212 | if (DeclNameExpr.isInvalid()) | ||||
1213 | return false; | ||||
1214 | |||||
1215 | if (!diagReturnOnAllocFailure(S, DeclNameExpr.get(), PromiseRecordDecl, Fn)) | ||||
1216 | return false; | ||||
1217 | |||||
1218 | ExprResult ReturnObjectOnAllocationFailure = | ||||
1219 | S.BuildCallExpr(nullptr, DeclNameExpr.get(), Loc, {}, Loc); | ||||
1220 | if (ReturnObjectOnAllocationFailure.isInvalid()) | ||||
1221 | return false; | ||||
1222 | |||||
1223 | StmtResult ReturnStmt = | ||||
1224 | S.BuildReturnStmt(Loc, ReturnObjectOnAllocationFailure.get()); | ||||
1225 | if (ReturnStmt.isInvalid()) { | ||||
1226 | S.Diag(Found.getFoundDecl()->getLocation(), diag::note_member_declared_here) | ||||
1227 | << DN; | ||||
1228 | S.Diag(Fn.FirstCoroutineStmtLoc, diag::note_declared_coroutine_here) | ||||
1229 | << Fn.getFirstCoroutineStmtKeyword(); | ||||
1230 | return false; | ||||
1231 | } | ||||
1232 | |||||
1233 | this->ReturnStmtOnAllocFailure = ReturnStmt.get(); | ||||
1234 | return true; | ||||
1235 | } | ||||
1236 | |||||
1237 | bool CoroutineStmtBuilder::makeNewAndDeleteExpr() { | ||||
1238 | // Form and check allocation and deallocation calls. | ||||
1239 | assert(!IsPromiseDependentType &&(static_cast <bool> (!IsPromiseDependentType && "cannot make statement while the promise type is dependent") ? void (0) : __assert_fail ("!IsPromiseDependentType && \"cannot make statement while the promise type is dependent\"" , "clang/lib/Sema/SemaCoroutine.cpp", 1240, __extension__ __PRETTY_FUNCTION__ )) | ||||
1240 | "cannot make statement while the promise type is dependent")(static_cast <bool> (!IsPromiseDependentType && "cannot make statement while the promise type is dependent") ? void (0) : __assert_fail ("!IsPromiseDependentType && \"cannot make statement while the promise type is dependent\"" , "clang/lib/Sema/SemaCoroutine.cpp", 1240, __extension__ __PRETTY_FUNCTION__ )); | ||||
1241 | QualType PromiseType = Fn.CoroutinePromise->getType(); | ||||
1242 | |||||
1243 | if (S.RequireCompleteType(Loc, PromiseType, diag::err_incomplete_type)) | ||||
1244 | return false; | ||||
1245 | |||||
1246 | const bool RequiresNoThrowAlloc = ReturnStmtOnAllocFailure != nullptr; | ||||
1247 | |||||
1248 | // According to [dcl.fct.def.coroutine]p9, Lookup allocation functions using a | ||||
1249 | // parameter list composed of the requested size of the coroutine state being | ||||
1250 | // allocated, followed by the coroutine function's arguments. If a matching | ||||
1251 | // allocation function exists, use it. Otherwise, use an allocation function | ||||
1252 | // that just takes the requested size. | ||||
1253 | |||||
1254 | FunctionDecl *OperatorNew = nullptr; | ||||
1255 | FunctionDecl *OperatorDelete = nullptr; | ||||
1256 | FunctionDecl *UnusedResult = nullptr; | ||||
1257 | bool PassAlignment = false; | ||||
1258 | SmallVector<Expr *, 1> PlacementArgs; | ||||
1259 | |||||
1260 | // [dcl.fct.def.coroutine]p9 | ||||
1261 | // An implementation may need to allocate additional storage for a | ||||
1262 | // coroutine. | ||||
1263 | // This storage is known as the coroutine state and is obtained by calling a | ||||
1264 | // non-array allocation function ([basic.stc.dynamic.allocation]). The | ||||
1265 | // allocation function's name is looked up by searching for it in the scope of | ||||
1266 | // the promise type. | ||||
1267 | // - If any declarations are found, overload resolution is performed on a | ||||
1268 | // function call created by assembling an argument list. The first argument is | ||||
1269 | // the amount of space requested, and has type std::size_t. The | ||||
1270 | // lvalues p1 ... pn are the succeeding arguments. | ||||
1271 | // | ||||
1272 | // ...where "p1 ... pn" are defined earlier as: | ||||
1273 | // | ||||
1274 | // [dcl.fct.def.coroutine]p3 | ||||
1275 | // The promise type of a coroutine is `std::coroutine_traits<R, P1, ..., | ||||
1276 | // Pn>` | ||||
1277 | // , where R is the return type of the function, and `P1, ..., Pn` are the | ||||
1278 | // sequence of types of the non-object function parameters, preceded by the | ||||
1279 | // type of the object parameter ([dcl.fct]) if the coroutine is a non-static | ||||
1280 | // member function. [dcl.fct.def.coroutine]p4 In the following, p_i is an | ||||
1281 | // lvalue of type P_i, where p1 denotes the object parameter and p_i+1 denotes | ||||
1282 | // the i-th non-object function parameter for a non-static member function, | ||||
1283 | // and p_i denotes the i-th function parameter otherwise. For a non-static | ||||
1284 | // member function, q_1 is an lvalue that denotes *this; any other q_i is an | ||||
1285 | // lvalue that denotes the parameter copy corresponding to p_i. | ||||
1286 | if (auto *MD = dyn_cast<CXXMethodDecl>(&FD)) { | ||||
1287 | if (MD->isInstance() && !isLambdaCallOperator(MD)) { | ||||
1288 | ExprResult ThisExpr = S.ActOnCXXThis(Loc); | ||||
1289 | if (ThisExpr.isInvalid()) | ||||
1290 | return false; | ||||
1291 | ThisExpr = S.CreateBuiltinUnaryOp(Loc, UO_Deref, ThisExpr.get()); | ||||
1292 | if (ThisExpr.isInvalid()) | ||||
1293 | return false; | ||||
1294 | PlacementArgs.push_back(ThisExpr.get()); | ||||
1295 | } | ||||
1296 | } | ||||
1297 | for (auto *PD : FD.parameters()) { | ||||
1298 | if (PD->getType()->isDependentType()) | ||||
1299 | continue; | ||||
1300 | |||||
1301 | // Build a reference to the parameter. | ||||
1302 | auto PDLoc = PD->getLocation(); | ||||
1303 | ExprResult PDRefExpr = | ||||
1304 | S.BuildDeclRefExpr(PD, PD->getOriginalType().getNonReferenceType(), | ||||
1305 | ExprValueKind::VK_LValue, PDLoc); | ||||
1306 | if (PDRefExpr.isInvalid()) | ||||
1307 | return false; | ||||
1308 | |||||
1309 | PlacementArgs.push_back(PDRefExpr.get()); | ||||
1310 | } | ||||
1311 | S.FindAllocationFunctions(Loc, SourceRange(), /*NewScope*/ Sema::AFS_Class, | ||||
1312 | /*DeleteScope*/ Sema::AFS_Both, PromiseType, | ||||
1313 | /*isArray*/ false, PassAlignment, PlacementArgs, | ||||
1314 | OperatorNew, UnusedResult, /*Diagnose*/ false); | ||||
1315 | |||||
1316 | // [dcl.fct.def.coroutine]p9 | ||||
1317 | // If no viable function is found ([over.match.viable]), overload resolution | ||||
1318 | // is performed again on a function call created by passing just the amount of | ||||
1319 | // space required as an argument of type std::size_t. | ||||
1320 | if (!OperatorNew && !PlacementArgs.empty()) { | ||||
1321 | PlacementArgs.clear(); | ||||
1322 | S.FindAllocationFunctions(Loc, SourceRange(), /*NewScope*/ Sema::AFS_Class, | ||||
1323 | /*DeleteScope*/ Sema::AFS_Both, PromiseType, | ||||
1324 | /*isArray*/ false, PassAlignment, PlacementArgs, | ||||
1325 | OperatorNew, UnusedResult, /*Diagnose*/ false); | ||||
1326 | } | ||||
1327 | |||||
1328 | // [dcl.fct.def.coroutine]p9 | ||||
1329 | // The allocation function's name is looked up by searching for it in the | ||||
1330 | // scope of the promise type. | ||||
1331 | // - If any declarations are found, ... | ||||
1332 | // - Otherwise, a search is performed in the global scope. | ||||
1333 | if (!OperatorNew) { | ||||
1334 | S.FindAllocationFunctions(Loc, SourceRange(), /*NewScope*/ Sema::AFS_Global, | ||||
1335 | /*DeleteScope*/ Sema::AFS_Both, PromiseType, | ||||
1336 | /*isArray*/ false, PassAlignment, PlacementArgs, | ||||
1337 | OperatorNew, UnusedResult); | ||||
1338 | } | ||||
1339 | |||||
1340 | bool IsGlobalOverload = | ||||
1341 | OperatorNew && !isa<CXXRecordDecl>(OperatorNew->getDeclContext()); | ||||
1342 | // If we didn't find a class-local new declaration and non-throwing new | ||||
1343 | // was is required then we need to lookup the non-throwing global operator | ||||
1344 | // instead. | ||||
1345 | if (RequiresNoThrowAlloc && (!OperatorNew || IsGlobalOverload)) { | ||||
1346 | auto *StdNoThrow = buildStdNoThrowDeclRef(S, Loc); | ||||
1347 | if (!StdNoThrow) | ||||
1348 | return false; | ||||
1349 | PlacementArgs = {StdNoThrow}; | ||||
1350 | OperatorNew = nullptr; | ||||
1351 | S.FindAllocationFunctions(Loc, SourceRange(), /*NewScope*/ Sema::AFS_Both, | ||||
1352 | /*DeleteScope*/ Sema::AFS_Both, PromiseType, | ||||
1353 | /*isArray*/ false, PassAlignment, PlacementArgs, | ||||
1354 | OperatorNew, UnusedResult); | ||||
1355 | } | ||||
1356 | |||||
1357 | if (!OperatorNew) | ||||
1358 | return false; | ||||
1359 | |||||
1360 | if (RequiresNoThrowAlloc) { | ||||
1361 | const auto *FT = OperatorNew->getType()->castAs<FunctionProtoType>(); | ||||
1362 | if (!FT->isNothrow(/*ResultIfDependent*/ false)) { | ||||
1363 | S.Diag(OperatorNew->getLocation(), | ||||
1364 | diag::err_coroutine_promise_new_requires_nothrow) | ||||
1365 | << OperatorNew; | ||||
1366 | S.Diag(Loc, diag::note_coroutine_promise_call_implicitly_required) | ||||
1367 | << OperatorNew; | ||||
1368 | return false; | ||||
1369 | } | ||||
1370 | } | ||||
1371 | |||||
1372 | if ((OperatorDelete = findDeleteForPromise(S, Loc, PromiseType)) == nullptr) { | ||||
1373 | // FIXME: We should add an error here. According to: | ||||
1374 | // [dcl.fct.def.coroutine]p12 | ||||
1375 | // If no usual deallocation function is found, the program is ill-formed. | ||||
1376 | return false; | ||||
1377 | } | ||||
1378 | |||||
1379 | Expr *FramePtr = | ||||
1380 | S.BuildBuiltinCallExpr(Loc, Builtin::BI__builtin_coro_frame, {}); | ||||
1381 | |||||
1382 | Expr *FrameSize = | ||||
1383 | S.BuildBuiltinCallExpr(Loc, Builtin::BI__builtin_coro_size, {}); | ||||
1384 | |||||
1385 | // Make new call. | ||||
1386 | |||||
1387 | ExprResult NewRef = | ||||
1388 | S.BuildDeclRefExpr(OperatorNew, OperatorNew->getType(), VK_LValue, Loc); | ||||
1389 | if (NewRef.isInvalid()) | ||||
1390 | return false; | ||||
1391 | |||||
1392 | SmallVector<Expr *, 2> NewArgs(1, FrameSize); | ||||
1393 | for (auto Arg : PlacementArgs) | ||||
1394 | NewArgs.push_back(Arg); | ||||
1395 | |||||
1396 | ExprResult NewExpr = | ||||
1397 | S.BuildCallExpr(S.getCurScope(), NewRef.get(), Loc, NewArgs, Loc); | ||||
1398 | NewExpr = S.ActOnFinishFullExpr(NewExpr.get(), /*DiscardedValue*/ false); | ||||
1399 | if (NewExpr.isInvalid()) | ||||
1400 | return false; | ||||
1401 | |||||
1402 | // Make delete call. | ||||
1403 | |||||
1404 | QualType OpDeleteQualType = OperatorDelete->getType(); | ||||
1405 | |||||
1406 | ExprResult DeleteRef = | ||||
1407 | S.BuildDeclRefExpr(OperatorDelete, OpDeleteQualType, VK_LValue, Loc); | ||||
1408 | if (DeleteRef.isInvalid()) | ||||
1409 | return false; | ||||
1410 | |||||
1411 | Expr *CoroFree = | ||||
1412 | S.BuildBuiltinCallExpr(Loc, Builtin::BI__builtin_coro_free, {FramePtr}); | ||||
1413 | |||||
1414 | SmallVector<Expr *, 2> DeleteArgs{CoroFree}; | ||||
1415 | |||||
1416 | // [dcl.fct.def.coroutine]p12 | ||||
1417 | // The selected deallocation function shall be called with the address of | ||||
1418 | // the block of storage to be reclaimed as its first argument. If a | ||||
1419 | // deallocation function with a parameter of type std::size_t is | ||||
1420 | // used, the size of the block is passed as the corresponding argument. | ||||
1421 | const auto *OpDeleteType = | ||||
1422 | OpDeleteQualType.getTypePtr()->castAs<FunctionProtoType>(); | ||||
1423 | if (OpDeleteType->getNumParams() > 1) | ||||
1424 | DeleteArgs.push_back(FrameSize); | ||||
1425 | |||||
1426 | ExprResult DeleteExpr = | ||||
1427 | S.BuildCallExpr(S.getCurScope(), DeleteRef.get(), Loc, DeleteArgs, Loc); | ||||
1428 | DeleteExpr = | ||||
1429 | S.ActOnFinishFullExpr(DeleteExpr.get(), /*DiscardedValue*/ false); | ||||
1430 | if (DeleteExpr.isInvalid()) | ||||
1431 | return false; | ||||
1432 | |||||
1433 | this->Allocate = NewExpr.get(); | ||||
1434 | this->Deallocate = DeleteExpr.get(); | ||||
1435 | |||||
1436 | return true; | ||||
1437 | } | ||||
1438 | |||||
1439 | bool CoroutineStmtBuilder::makeOnFallthrough() { | ||||
1440 | assert(!IsPromiseDependentType &&(static_cast <bool> (!IsPromiseDependentType && "cannot make statement while the promise type is dependent") ? void (0) : __assert_fail ("!IsPromiseDependentType && \"cannot make statement while the promise type is dependent\"" , "clang/lib/Sema/SemaCoroutine.cpp", 1441, __extension__ __PRETTY_FUNCTION__ )) | ||||
1441 | "cannot make statement while the promise type is dependent")(static_cast <bool> (!IsPromiseDependentType && "cannot make statement while the promise type is dependent") ? void (0) : __assert_fail ("!IsPromiseDependentType && \"cannot make statement while the promise type is dependent\"" , "clang/lib/Sema/SemaCoroutine.cpp", 1441, __extension__ __PRETTY_FUNCTION__ )); | ||||
1442 | |||||
1443 | // [dcl.fct.def.coroutine]/p6 | ||||
1444 | // If searches for the names return_void and return_value in the scope of | ||||
1445 | // the promise type each find any declarations, the program is ill-formed. | ||||
1446 | // [Note 1: If return_void is found, flowing off the end of a coroutine is | ||||
1447 | // equivalent to a co_return with no operand. Otherwise, flowing off the end | ||||
1448 | // of a coroutine results in undefined behavior ([stmt.return.coroutine]). — | ||||
1449 | // end note] | ||||
1450 | bool HasRVoid, HasRValue; | ||||
1451 | LookupResult LRVoid = | ||||
1452 | lookupMember(S, "return_void", PromiseRecordDecl, Loc, HasRVoid); | ||||
1453 | LookupResult LRValue = | ||||
1454 | lookupMember(S, "return_value", PromiseRecordDecl, Loc, HasRValue); | ||||
1455 | |||||
1456 | StmtResult Fallthrough; | ||||
1457 | if (HasRVoid && HasRValue) { | ||||
1458 | // FIXME Improve this diagnostic | ||||
1459 | S.Diag(FD.getLocation(), | ||||
1460 | diag::err_coroutine_promise_incompatible_return_functions) | ||||
1461 | << PromiseRecordDecl; | ||||
1462 | S.Diag(LRVoid.getRepresentativeDecl()->getLocation(), | ||||
1463 | diag::note_member_first_declared_here) | ||||
1464 | << LRVoid.getLookupName(); | ||||
1465 | S.Diag(LRValue.getRepresentativeDecl()->getLocation(), | ||||
1466 | diag::note_member_first_declared_here) | ||||
1467 | << LRValue.getLookupName(); | ||||
1468 | return false; | ||||
1469 | } else if (!HasRVoid && !HasRValue) { | ||||
1470 | // We need to set 'Fallthrough'. Otherwise the other analysis part might | ||||
1471 | // think the coroutine has defined a return_value method. So it might emit | ||||
1472 | // **false** positive warning. e.g., | ||||
1473 | // | ||||
1474 | // promise_without_return_func foo() { | ||||
1475 | // co_await something(); | ||||
1476 | // } | ||||
1477 | // | ||||
1478 | // Then AnalysisBasedWarning would emit a warning about `foo()` lacking a | ||||
1479 | // co_return statements, which isn't correct. | ||||
1480 | Fallthrough = S.ActOnNullStmt(PromiseRecordDecl->getLocation()); | ||||
1481 | if (Fallthrough.isInvalid()) | ||||
1482 | return false; | ||||
1483 | } else if (HasRVoid) { | ||||
1484 | Fallthrough = S.BuildCoreturnStmt(FD.getLocation(), nullptr, | ||||
1485 | /*IsImplicit*/false); | ||||
1486 | Fallthrough = S.ActOnFinishFullStmt(Fallthrough.get()); | ||||
1487 | if (Fallthrough.isInvalid()) | ||||
1488 | return false; | ||||
1489 | } | ||||
1490 | |||||
1491 | this->OnFallthrough = Fallthrough.get(); | ||||
1492 | return true; | ||||
1493 | } | ||||
1494 | |||||
1495 | bool CoroutineStmtBuilder::makeOnException() { | ||||
1496 | // Try to form 'p.unhandled_exception();' | ||||
1497 | assert(!IsPromiseDependentType &&(static_cast <bool> (!IsPromiseDependentType && "cannot make statement while the promise type is dependent") ? void (0) : __assert_fail ("!IsPromiseDependentType && \"cannot make statement while the promise type is dependent\"" , "clang/lib/Sema/SemaCoroutine.cpp", 1498, __extension__ __PRETTY_FUNCTION__ )) | ||||
1498 | "cannot make statement while the promise type is dependent")(static_cast <bool> (!IsPromiseDependentType && "cannot make statement while the promise type is dependent") ? void (0) : __assert_fail ("!IsPromiseDependentType && \"cannot make statement while the promise type is dependent\"" , "clang/lib/Sema/SemaCoroutine.cpp", 1498, __extension__ __PRETTY_FUNCTION__ )); | ||||
1499 | |||||
1500 | const bool RequireUnhandledException = S.getLangOpts().CXXExceptions; | ||||
1501 | |||||
1502 | if (!lookupMember(S, "unhandled_exception", PromiseRecordDecl, Loc)) { | ||||
1503 | auto DiagID = | ||||
1504 | RequireUnhandledException | ||||
1505 | ? diag::err_coroutine_promise_unhandled_exception_required | ||||
1506 | : diag:: | ||||
1507 | warn_coroutine_promise_unhandled_exception_required_with_exceptions; | ||||
1508 | S.Diag(Loc, DiagID) << PromiseRecordDecl; | ||||
1509 | S.Diag(PromiseRecordDecl->getLocation(), diag::note_defined_here) | ||||
1510 | << PromiseRecordDecl; | ||||
1511 | return !RequireUnhandledException; | ||||
1512 | } | ||||
1513 | |||||
1514 | // If exceptions are disabled, don't try to build OnException. | ||||
1515 | if (!S.getLangOpts().CXXExceptions) | ||||
1516 | return true; | ||||
1517 | |||||
1518 | ExprResult UnhandledException = buildPromiseCall(S, Fn.CoroutinePromise, Loc, | ||||
1519 | "unhandled_exception", None); | ||||
1520 | UnhandledException = S.ActOnFinishFullExpr(UnhandledException.get(), Loc, | ||||
1521 | /*DiscardedValue*/ false); | ||||
1522 | if (UnhandledException.isInvalid()) | ||||
1523 | return false; | ||||
1524 | |||||
1525 | // Since the body of the coroutine will be wrapped in try-catch, it will | ||||
1526 | // be incompatible with SEH __try if present in a function. | ||||
1527 | if (!S.getLangOpts().Borland && Fn.FirstSEHTryLoc.isValid()) { | ||||
1528 | S.Diag(Fn.FirstSEHTryLoc, diag::err_seh_in_a_coroutine_with_cxx_exceptions); | ||||
1529 | S.Diag(Fn.FirstCoroutineStmtLoc, diag::note_declared_coroutine_here) | ||||
1530 | << Fn.getFirstCoroutineStmtKeyword(); | ||||
1531 | return false; | ||||
1532 | } | ||||
1533 | |||||
1534 | this->OnException = UnhandledException.get(); | ||||
1535 | return true; | ||||
1536 | } | ||||
1537 | |||||
1538 | bool CoroutineStmtBuilder::makeReturnObject() { | ||||
1539 | // [dcl.fct.def.coroutine]p7 | ||||
1540 | // The expression promise.get_return_object() is used to initialize the | ||||
1541 | // returned reference or prvalue result object of a call to a coroutine. | ||||
1542 | ExprResult ReturnObject = | ||||
1543 | buildPromiseCall(S, Fn.CoroutinePromise, Loc, "get_return_object", None); | ||||
1544 | if (ReturnObject.isInvalid()) | ||||
1545 | return false; | ||||
1546 | |||||
1547 | this->ReturnValue = ReturnObject.get(); | ||||
1548 | return true; | ||||
1549 | } | ||||
1550 | |||||
1551 | static void noteMemberDeclaredHere(Sema &S, Expr *E, FunctionScopeInfo &Fn) { | ||||
1552 | if (auto *MbrRef = dyn_cast<CXXMemberCallExpr>(E)) { | ||||
1553 | auto *MethodDecl = MbrRef->getMethodDecl(); | ||||
1554 | S.Diag(MethodDecl->getLocation(), diag::note_member_declared_here) | ||||
1555 | << MethodDecl; | ||||
1556 | } | ||||
1557 | S.Diag(Fn.FirstCoroutineStmtLoc, diag::note_declared_coroutine_here) | ||||
1558 | << Fn.getFirstCoroutineStmtKeyword(); | ||||
1559 | } | ||||
1560 | |||||
1561 | bool CoroutineStmtBuilder::makeGroDeclAndReturnStmt() { | ||||
1562 | assert(!IsPromiseDependentType &&(static_cast <bool> (!IsPromiseDependentType && "cannot make statement while the promise type is dependent") ? void (0) : __assert_fail ("!IsPromiseDependentType && \"cannot make statement while the promise type is dependent\"" , "clang/lib/Sema/SemaCoroutine.cpp", 1563, __extension__ __PRETTY_FUNCTION__ )) | ||||
1563 | "cannot make statement while the promise type is dependent")(static_cast <bool> (!IsPromiseDependentType && "cannot make statement while the promise type is dependent") ? void (0) : __assert_fail ("!IsPromiseDependentType && \"cannot make statement while the promise type is dependent\"" , "clang/lib/Sema/SemaCoroutine.cpp", 1563, __extension__ __PRETTY_FUNCTION__ )); | ||||
1564 | assert(this->ReturnValue && "ReturnValue must be already formed")(static_cast <bool> (this->ReturnValue && "ReturnValue must be already formed" ) ? void (0) : __assert_fail ("this->ReturnValue && \"ReturnValue must be already formed\"" , "clang/lib/Sema/SemaCoroutine.cpp", 1564, __extension__ __PRETTY_FUNCTION__ )); | ||||
1565 | |||||
1566 | QualType const GroType = this->ReturnValue->getType(); | ||||
1567 | assert(!GroType->isDependentType() &&(static_cast <bool> (!GroType->isDependentType() && "get_return_object type must no longer be dependent") ? void (0) : __assert_fail ("!GroType->isDependentType() && \"get_return_object type must no longer be dependent\"" , "clang/lib/Sema/SemaCoroutine.cpp", 1568, __extension__ __PRETTY_FUNCTION__ )) | ||||
1568 | "get_return_object type must no longer be dependent")(static_cast <bool> (!GroType->isDependentType() && "get_return_object type must no longer be dependent") ? void (0) : __assert_fail ("!GroType->isDependentType() && \"get_return_object type must no longer be dependent\"" , "clang/lib/Sema/SemaCoroutine.cpp", 1568, __extension__ __PRETTY_FUNCTION__ )); | ||||
1569 | |||||
1570 | QualType const FnRetType = FD.getReturnType(); | ||||
1571 | assert(!FnRetType->isDependentType() &&(static_cast <bool> (!FnRetType->isDependentType() && "get_return_object type must no longer be dependent") ? void (0) : __assert_fail ("!FnRetType->isDependentType() && \"get_return_object type must no longer be dependent\"" , "clang/lib/Sema/SemaCoroutine.cpp", 1572, __extension__ __PRETTY_FUNCTION__ )) | ||||
1572 | "get_return_object type must no longer be dependent")(static_cast <bool> (!FnRetType->isDependentType() && "get_return_object type must no longer be dependent") ? void (0) : __assert_fail ("!FnRetType->isDependentType() && \"get_return_object type must no longer be dependent\"" , "clang/lib/Sema/SemaCoroutine.cpp", 1572, __extension__ __PRETTY_FUNCTION__ )); | ||||
1573 | |||||
1574 | if (FnRetType->isVoidType()) { | ||||
1575 | ExprResult Res = | ||||
1576 | S.ActOnFinishFullExpr(this->ReturnValue, Loc, /*DiscardedValue*/ false); | ||||
1577 | if (Res.isInvalid()) | ||||
1578 | return false; | ||||
1579 | |||||
1580 | this->ResultDecl = Res.get(); | ||||
1581 | return true; | ||||
1582 | } | ||||
1583 | |||||
1584 | if (GroType->isVoidType()) { | ||||
1585 | // Trigger a nice error message. | ||||
1586 | InitializedEntity Entity = | ||||
1587 | InitializedEntity::InitializeResult(Loc, FnRetType); | ||||
1588 | S.PerformCopyInitialization(Entity, SourceLocation(), ReturnValue); | ||||
1589 | noteMemberDeclaredHere(S, ReturnValue, Fn); | ||||
1590 | return false; | ||||
1591 | } | ||||
1592 | |||||
1593 | auto *GroDecl = VarDecl::Create( | ||||
1594 | S.Context, &FD, FD.getLocation(), FD.getLocation(), | ||||
1595 | &S.PP.getIdentifierTable().get("__coro_gro"), GroType, | ||||
1596 | S.Context.getTrivialTypeSourceInfo(GroType, Loc), SC_None); | ||||
1597 | GroDecl->setImplicit(); | ||||
1598 | |||||
1599 | S.CheckVariableDeclarationType(GroDecl); | ||||
1600 | if (GroDecl->isInvalidDecl()) | ||||
1601 | return false; | ||||
1602 | |||||
1603 | InitializedEntity Entity = InitializedEntity::InitializeVariable(GroDecl); | ||||
1604 | ExprResult Res = | ||||
1605 | S.PerformCopyInitialization(Entity, SourceLocation(), ReturnValue); | ||||
1606 | if (Res.isInvalid()) | ||||
1607 | return false; | ||||
1608 | |||||
1609 | Res = S.ActOnFinishFullExpr(Res.get(), /*DiscardedValue*/ false); | ||||
1610 | if (Res.isInvalid()) | ||||
1611 | return false; | ||||
1612 | |||||
1613 | S.AddInitializerToDecl(GroDecl, Res.get(), | ||||
1614 | /*DirectInit=*/false); | ||||
1615 | |||||
1616 | S.FinalizeDeclaration(GroDecl); | ||||
1617 | |||||
1618 | // Form a declaration statement for the return declaration, so that AST | ||||
1619 | // visitors can more easily find it. | ||||
1620 | StmtResult GroDeclStmt = | ||||
1621 | S.ActOnDeclStmt(S.ConvertDeclToDeclGroup(GroDecl), Loc, Loc); | ||||
1622 | if (GroDeclStmt.isInvalid()) | ||||
1623 | return false; | ||||
1624 | |||||
1625 | this->ResultDecl = GroDeclStmt.get(); | ||||
1626 | |||||
1627 | ExprResult declRef = S.BuildDeclRefExpr(GroDecl, GroType, VK_LValue, Loc); | ||||
1628 | if (declRef.isInvalid()) | ||||
1629 | return false; | ||||
1630 | |||||
1631 | StmtResult ReturnStmt = S.BuildReturnStmt(Loc, declRef.get()); | ||||
1632 | if (ReturnStmt.isInvalid()) { | ||||
1633 | noteMemberDeclaredHere(S, ReturnValue, Fn); | ||||
1634 | return false; | ||||
1635 | } | ||||
1636 | if (cast<clang::ReturnStmt>(ReturnStmt.get())->getNRVOCandidate() == GroDecl) | ||||
1637 | GroDecl->setNRVOVariable(true); | ||||
1638 | |||||
1639 | this->ReturnStmt = ReturnStmt.get(); | ||||
1640 | return true; | ||||
1641 | } | ||||
1642 | |||||
1643 | // Create a static_cast\<T&&>(expr). | ||||
1644 | static Expr *castForMoving(Sema &S, Expr *E, QualType T = QualType()) { | ||||
1645 | if (T.isNull()) | ||||
1646 | T = E->getType(); | ||||
1647 | QualType TargetType = S.BuildReferenceType( | ||||
1648 | T, /*SpelledAsLValue*/ false, SourceLocation(), DeclarationName()); | ||||
1649 | SourceLocation ExprLoc = E->getBeginLoc(); | ||||
1650 | TypeSourceInfo *TargetLoc = | ||||
1651 | S.Context.getTrivialTypeSourceInfo(TargetType, ExprLoc); | ||||
1652 | |||||
1653 | return S | ||||
1654 | .BuildCXXNamedCast(ExprLoc, tok::kw_static_cast, TargetLoc, E, | ||||
1655 | SourceRange(ExprLoc, ExprLoc), E->getSourceRange()) | ||||
1656 | .get(); | ||||
1657 | } | ||||
1658 | |||||
1659 | /// Build a variable declaration for move parameter. | ||||
1660 | static VarDecl *buildVarDecl(Sema &S, SourceLocation Loc, QualType Type, | ||||
1661 | IdentifierInfo *II) { | ||||
1662 | TypeSourceInfo *TInfo = S.Context.getTrivialTypeSourceInfo(Type, Loc); | ||||
1663 | VarDecl *Decl = VarDecl::Create(S.Context, S.CurContext, Loc, Loc, II, Type, | ||||
1664 | TInfo, SC_None); | ||||
1665 | Decl->setImplicit(); | ||||
1666 | return Decl; | ||||
1667 | } | ||||
1668 | |||||
1669 | // Build statements that move coroutine function parameters to the coroutine | ||||
1670 | // frame, and store them on the function scope info. | ||||
1671 | bool Sema::buildCoroutineParameterMoves(SourceLocation Loc) { | ||||
1672 | assert(isa<FunctionDecl>(CurContext) && "not in a function scope")(static_cast <bool> (isa<FunctionDecl>(CurContext ) && "not in a function scope") ? void (0) : __assert_fail ("isa<FunctionDecl>(CurContext) && \"not in a function scope\"" , "clang/lib/Sema/SemaCoroutine.cpp", 1672, __extension__ __PRETTY_FUNCTION__ )); | ||||
1673 | auto *FD = cast<FunctionDecl>(CurContext); | ||||
1674 | |||||
1675 | auto *ScopeInfo = getCurFunction(); | ||||
1676 | if (!ScopeInfo->CoroutineParameterMoves.empty()) | ||||
1677 | return false; | ||||
1678 | |||||
1679 | // [dcl.fct.def.coroutine]p13 | ||||
1680 | // When a coroutine is invoked, after initializing its parameters | ||||
1681 | // ([expr.call]), a copy is created for each coroutine parameter. For a | ||||
1682 | // parameter of type cv T, the copy is a variable of type cv T with | ||||
1683 | // automatic storage duration that is direct-initialized from an xvalue of | ||||
1684 | // type T referring to the parameter. | ||||
1685 | for (auto *PD : FD->parameters()) { | ||||
1686 | if (PD->getType()->isDependentType()) | ||||
1687 | continue; | ||||
1688 | |||||
1689 | ExprResult PDRefExpr = | ||||
1690 | BuildDeclRefExpr(PD, PD->getType().getNonReferenceType(), | ||||
1691 | ExprValueKind::VK_LValue, Loc); // FIXME: scope? | ||||
1692 | if (PDRefExpr.isInvalid()) | ||||
1693 | return false; | ||||
1694 | |||||
1695 | Expr *CExpr = nullptr; | ||||
1696 | if (PD->getType()->getAsCXXRecordDecl() || | ||||
1697 | PD->getType()->isRValueReferenceType()) | ||||
1698 | CExpr = castForMoving(*this, PDRefExpr.get()); | ||||
1699 | else | ||||
1700 | CExpr = PDRefExpr.get(); | ||||
1701 | // [dcl.fct.def.coroutine]p13 | ||||
1702 | // The initialization and destruction of each parameter copy occurs in the | ||||
1703 | // context of the called coroutine. | ||||
1704 | auto D = buildVarDecl(*this, Loc, PD->getType(), PD->getIdentifier()); | ||||
1705 | AddInitializerToDecl(D, CExpr, /*DirectInit=*/true); | ||||
1706 | |||||
1707 | // Convert decl to a statement. | ||||
1708 | StmtResult Stmt = ActOnDeclStmt(ConvertDeclToDeclGroup(D), Loc, Loc); | ||||
1709 | if (Stmt.isInvalid()) | ||||
1710 | return false; | ||||
1711 | |||||
1712 | ScopeInfo->CoroutineParameterMoves.insert(std::make_pair(PD, Stmt.get())); | ||||
1713 | } | ||||
1714 | return true; | ||||
1715 | } | ||||
1716 | |||||
1717 | StmtResult Sema::BuildCoroutineBodyStmt(CoroutineBodyStmt::CtorArgs Args) { | ||||
1718 | CoroutineBodyStmt *Res = CoroutineBodyStmt::Create(Context, Args); | ||||
1719 | if (!Res) | ||||
1720 | return StmtError(); | ||||
1721 | return Res; | ||||
1722 | } | ||||
1723 | |||||
1724 | ClassTemplateDecl *Sema::lookupCoroutineTraits(SourceLocation KwLoc, | ||||
1725 | SourceLocation FuncLoc, | ||||
1726 | NamespaceDecl *&Namespace) { | ||||
1727 | if (!StdCoroutineTraitsCache) { | ||||
1728 | // Because coroutines moved from std::experimental in the TS to std in | ||||
1729 | // C++20, we look in both places to give users time to transition their | ||||
1730 | // TS-specific code to C++20. Diagnostics are given when the TS usage is | ||||
1731 | // discovered. | ||||
1732 | // TODO: Become stricter when <experimental/coroutine> is removed. | ||||
1733 | |||||
1734 | auto const &TraitIdent = PP.getIdentifierTable().get("coroutine_traits"); | ||||
1735 | |||||
1736 | NamespaceDecl *StdSpace = getStdNamespace(); | ||||
1737 | LookupResult ResStd(*this, &TraitIdent, FuncLoc, LookupOrdinaryName); | ||||
1738 | bool InStd = StdSpace && LookupQualifiedName(ResStd, StdSpace); | ||||
1739 | |||||
1740 | NamespaceDecl *ExpSpace = lookupStdExperimentalNamespace(); | ||||
1741 | LookupResult ResExp(*this, &TraitIdent, FuncLoc, LookupOrdinaryName); | ||||
1742 | bool InExp = ExpSpace && LookupQualifiedName(ResExp, ExpSpace); | ||||
1743 | |||||
1744 | if (!InStd && !InExp) { | ||||
1745 | // The goggles, they found nothing! | ||||
1746 | Diag(KwLoc, diag::err_implied_coroutine_type_not_found) | ||||
1747 | << "std::coroutine_traits"; | ||||
1748 | return nullptr; | ||||
1749 | } | ||||
1750 | |||||
1751 | // Prefer ::std to std::experimental. | ||||
1752 | auto &Result = InStd ? ResStd : ResExp; | ||||
1753 | CoroTraitsNamespaceCache = InStd ? StdSpace : ExpSpace; | ||||
1754 | |||||
1755 | // coroutine_traits is required to be a class template. | ||||
1756 | StdCoroutineTraitsCache = Result.getAsSingle<ClassTemplateDecl>(); | ||||
1757 | if (!StdCoroutineTraitsCache) { | ||||
1758 | Result.suppressDiagnostics(); | ||||
1759 | NamedDecl *Found = *Result.begin(); | ||||
1760 | Diag(Found->getLocation(), diag::err_malformed_std_coroutine_traits); | ||||
1761 | return nullptr; | ||||
1762 | } | ||||
1763 | |||||
1764 | if (InExp) { | ||||
1765 | // Found in std::experimental | ||||
1766 | Diag(KwLoc, diag::warn_deprecated_coroutine_namespace) | ||||
1767 | << "coroutine_traits"; | ||||
1768 | ResExp.suppressDiagnostics(); | ||||
1769 | auto *Found = *ResExp.begin(); | ||||
1770 | Diag(Found->getLocation(), diag::note_entity_declared_at) << Found; | ||||
1771 | |||||
1772 | if (InStd && | ||||
1773 | StdCoroutineTraitsCache != ResExp.getAsSingle<ClassTemplateDecl>()) { | ||||
1774 | // Also found something different in std | ||||
1775 | Diag(KwLoc, | ||||
1776 | diag::err_mixed_use_std_and_experimental_namespace_for_coroutine); | ||||
1777 | Diag(StdCoroutineTraitsCache->getLocation(), | ||||
1778 | diag::note_entity_declared_at) | ||||
1779 | << StdCoroutineTraitsCache; | ||||
1780 | |||||
1781 | return nullptr; | ||||
1782 | } | ||||
1783 | } | ||||
1784 | } | ||||
1785 | Namespace = CoroTraitsNamespaceCache; | ||||
1786 | return StdCoroutineTraitsCache; | ||||
1787 | } |