File: | clang/lib/Sema/SemaCoroutine.cpp |
Warning: | line 700, column 13 Called C++ object pointer is null |
Press '?' to see keyboard shortcuts
Keyboard shortcuts:
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 | // FIXME: Cache std::coroutine_traits once we've found it. | |||
57 | NamespaceDecl *StdExp = S.lookupStdExperimentalNamespace(); | |||
58 | if (!StdExp) { | |||
59 | S.Diag(KwLoc, diag::err_implied_coroutine_type_not_found) | |||
60 | << "std::experimental::coroutine_traits"; | |||
61 | return QualType(); | |||
62 | } | |||
63 | ||||
64 | ClassTemplateDecl *CoroTraits = S.lookupCoroutineTraits(KwLoc, FuncLoc); | |||
65 | if (!CoroTraits) { | |||
66 | return QualType(); | |||
67 | } | |||
68 | ||||
69 | // Form template argument list for coroutine_traits<R, P1, P2, ...> according | |||
70 | // to [dcl.fct.def.coroutine]3 | |||
71 | TemplateArgumentListInfo Args(KwLoc, KwLoc); | |||
72 | auto AddArg = [&](QualType T) { | |||
73 | Args.addArgument(TemplateArgumentLoc( | |||
74 | TemplateArgument(T), S.Context.getTrivialTypeSourceInfo(T, KwLoc))); | |||
75 | }; | |||
76 | AddArg(FnType->getReturnType()); | |||
77 | // If the function is a non-static member function, add the type | |||
78 | // of the implicit object parameter before the formal parameters. | |||
79 | if (auto *MD = dyn_cast<CXXMethodDecl>(FD)) { | |||
80 | if (MD->isInstance()) { | |||
81 | // [over.match.funcs]4 | |||
82 | // For non-static member functions, the type of the implicit object | |||
83 | // parameter is | |||
84 | // -- "lvalue reference to cv X" for functions declared without a | |||
85 | // ref-qualifier or with the & ref-qualifier | |||
86 | // -- "rvalue reference to cv X" for functions declared with the && | |||
87 | // ref-qualifier | |||
88 | QualType T = MD->getThisType()->castAs<PointerType>()->getPointeeType(); | |||
89 | T = FnType->getRefQualifier() == RQ_RValue | |||
90 | ? S.Context.getRValueReferenceType(T) | |||
91 | : S.Context.getLValueReferenceType(T, /*SpelledAsLValue*/ true); | |||
92 | AddArg(T); | |||
93 | } | |||
94 | } | |||
95 | for (QualType T : FnType->getParamTypes()) | |||
96 | AddArg(T); | |||
97 | ||||
98 | // Build the template-id. | |||
99 | QualType CoroTrait = | |||
100 | S.CheckTemplateIdType(TemplateName(CoroTraits), KwLoc, Args); | |||
101 | if (CoroTrait.isNull()) | |||
102 | return QualType(); | |||
103 | if (S.RequireCompleteType(KwLoc, CoroTrait, | |||
104 | diag::err_coroutine_type_missing_specialization)) | |||
105 | return QualType(); | |||
106 | ||||
107 | auto *RD = CoroTrait->getAsCXXRecordDecl(); | |||
108 | assert(RD && "specialization of class template is not a class?")((RD && "specialization of class template is not a class?" ) ? static_cast<void> (0) : __assert_fail ("RD && \"specialization of class template is not a class?\"" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaCoroutine.cpp" , 108, __PRETTY_FUNCTION__)); | |||
109 | ||||
110 | // Look up the ::promise_type member. | |||
111 | LookupResult R(S, &S.PP.getIdentifierTable().get("promise_type"), KwLoc, | |||
112 | Sema::LookupOrdinaryName); | |||
113 | S.LookupQualifiedName(R, RD); | |||
114 | auto *Promise = R.getAsSingle<TypeDecl>(); | |||
115 | if (!Promise) { | |||
116 | S.Diag(FuncLoc, | |||
117 | diag::err_implied_std_coroutine_traits_promise_type_not_found) | |||
118 | << RD; | |||
119 | return QualType(); | |||
120 | } | |||
121 | // The promise type is required to be a class type. | |||
122 | QualType PromiseType = S.Context.getTypeDeclType(Promise); | |||
123 | ||||
124 | auto buildElaboratedType = [&]() { | |||
125 | auto *NNS = NestedNameSpecifier::Create(S.Context, nullptr, StdExp); | |||
126 | NNS = NestedNameSpecifier::Create(S.Context, NNS, false, | |||
127 | CoroTrait.getTypePtr()); | |||
128 | return S.Context.getElaboratedType(ETK_None, NNS, PromiseType); | |||
129 | }; | |||
130 | ||||
131 | if (!PromiseType->getAsCXXRecordDecl()) { | |||
132 | S.Diag(FuncLoc, | |||
133 | diag::err_implied_std_coroutine_traits_promise_type_not_class) | |||
134 | << buildElaboratedType(); | |||
135 | return QualType(); | |||
136 | } | |||
137 | if (S.RequireCompleteType(FuncLoc, buildElaboratedType(), | |||
138 | diag::err_coroutine_promise_type_incomplete)) | |||
139 | return QualType(); | |||
140 | ||||
141 | return PromiseType; | |||
142 | } | |||
143 | ||||
144 | /// Look up the std::experimental::coroutine_handle<PromiseType>. | |||
145 | static QualType lookupCoroutineHandleType(Sema &S, QualType PromiseType, | |||
146 | SourceLocation Loc) { | |||
147 | if (PromiseType.isNull()) | |||
148 | return QualType(); | |||
149 | ||||
150 | NamespaceDecl *StdExp = S.lookupStdExperimentalNamespace(); | |||
151 | assert(StdExp && "Should already be diagnosed")((StdExp && "Should already be diagnosed") ? static_cast <void> (0) : __assert_fail ("StdExp && \"Should already be diagnosed\"" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaCoroutine.cpp" , 151, __PRETTY_FUNCTION__)); | |||
152 | ||||
153 | LookupResult Result(S, &S.PP.getIdentifierTable().get("coroutine_handle"), | |||
154 | Loc, Sema::LookupOrdinaryName); | |||
155 | if (!S.LookupQualifiedName(Result, StdExp)) { | |||
156 | S.Diag(Loc, diag::err_implied_coroutine_type_not_found) | |||
157 | << "std::experimental::coroutine_handle"; | |||
158 | return QualType(); | |||
159 | } | |||
160 | ||||
161 | ClassTemplateDecl *CoroHandle = Result.getAsSingle<ClassTemplateDecl>(); | |||
162 | if (!CoroHandle) { | |||
163 | Result.suppressDiagnostics(); | |||
164 | // We found something weird. Complain about the first thing we found. | |||
165 | NamedDecl *Found = *Result.begin(); | |||
166 | S.Diag(Found->getLocation(), diag::err_malformed_std_coroutine_handle); | |||
167 | return QualType(); | |||
168 | } | |||
169 | ||||
170 | // Form template argument list for coroutine_handle<Promise>. | |||
171 | TemplateArgumentListInfo Args(Loc, Loc); | |||
172 | Args.addArgument(TemplateArgumentLoc( | |||
173 | TemplateArgument(PromiseType), | |||
174 | S.Context.getTrivialTypeSourceInfo(PromiseType, Loc))); | |||
175 | ||||
176 | // Build the template-id. | |||
177 | QualType CoroHandleType = | |||
178 | S.CheckTemplateIdType(TemplateName(CoroHandle), Loc, Args); | |||
179 | if (CoroHandleType.isNull()) | |||
180 | return QualType(); | |||
181 | if (S.RequireCompleteType(Loc, CoroHandleType, | |||
182 | diag::err_coroutine_type_missing_specialization)) | |||
183 | return QualType(); | |||
184 | ||||
185 | return CoroHandleType; | |||
186 | } | |||
187 | ||||
188 | static bool isValidCoroutineContext(Sema &S, SourceLocation Loc, | |||
189 | StringRef Keyword) { | |||
190 | // [expr.await]p2 dictates that 'co_await' and 'co_yield' must be used within | |||
191 | // a function body. | |||
192 | // FIXME: This also covers [expr.await]p2: "An await-expression shall not | |||
193 | // appear in a default argument." But the diagnostic QoI here could be | |||
194 | // improved to inform the user that default arguments specifically are not | |||
195 | // allowed. | |||
196 | auto *FD = dyn_cast<FunctionDecl>(S.CurContext); | |||
197 | if (!FD) { | |||
198 | S.Diag(Loc, isa<ObjCMethodDecl>(S.CurContext) | |||
199 | ? diag::err_coroutine_objc_method | |||
200 | : diag::err_coroutine_outside_function) << Keyword; | |||
201 | return false; | |||
202 | } | |||
203 | ||||
204 | // An enumeration for mapping the diagnostic type to the correct diagnostic | |||
205 | // selection index. | |||
206 | enum InvalidFuncDiag { | |||
207 | DiagCtor = 0, | |||
208 | DiagDtor, | |||
209 | DiagMain, | |||
210 | DiagConstexpr, | |||
211 | DiagAutoRet, | |||
212 | DiagVarargs, | |||
213 | DiagConsteval, | |||
214 | }; | |||
215 | bool Diagnosed = false; | |||
216 | auto DiagInvalid = [&](InvalidFuncDiag ID) { | |||
217 | S.Diag(Loc, diag::err_coroutine_invalid_func_context) << ID << Keyword; | |||
218 | Diagnosed = true; | |||
219 | return false; | |||
220 | }; | |||
221 | ||||
222 | // Diagnose when a constructor, destructor | |||
223 | // or the function 'main' are declared as a coroutine. | |||
224 | auto *MD = dyn_cast<CXXMethodDecl>(FD); | |||
225 | // [class.ctor]p11: "A constructor shall not be a coroutine." | |||
226 | if (MD && isa<CXXConstructorDecl>(MD)) | |||
227 | return DiagInvalid(DiagCtor); | |||
228 | // [class.dtor]p17: "A destructor shall not be a coroutine." | |||
229 | else if (MD && isa<CXXDestructorDecl>(MD)) | |||
230 | return DiagInvalid(DiagDtor); | |||
231 | // [basic.start.main]p3: "The function main shall not be a coroutine." | |||
232 | else if (FD->isMain()) | |||
233 | return DiagInvalid(DiagMain); | |||
234 | ||||
235 | // Emit a diagnostics for each of the following conditions which is not met. | |||
236 | // [expr.const]p2: "An expression e is a core constant expression unless the | |||
237 | // evaluation of e [...] would evaluate one of the following expressions: | |||
238 | // [...] an await-expression [...] a yield-expression." | |||
239 | if (FD->isConstexpr()) | |||
240 | DiagInvalid(FD->isConsteval() ? DiagConsteval : DiagConstexpr); | |||
241 | // [dcl.spec.auto]p15: "A function declared with a return type that uses a | |||
242 | // placeholder type shall not be a coroutine." | |||
243 | if (FD->getReturnType()->isUndeducedType()) | |||
244 | DiagInvalid(DiagAutoRet); | |||
245 | // [dcl.fct.def.coroutine]p1: "The parameter-declaration-clause of the | |||
246 | // coroutine shall not terminate with an ellipsis that is not part of a | |||
247 | // parameter-declaration." | |||
248 | if (FD->isVariadic()) | |||
249 | DiagInvalid(DiagVarargs); | |||
250 | ||||
251 | return !Diagnosed; | |||
252 | } | |||
253 | ||||
254 | static ExprResult buildOperatorCoawaitLookupExpr(Sema &SemaRef, Scope *S, | |||
255 | SourceLocation Loc) { | |||
256 | DeclarationName OpName = | |||
257 | SemaRef.Context.DeclarationNames.getCXXOperatorName(OO_Coawait); | |||
258 | LookupResult Operators(SemaRef, OpName, SourceLocation(), | |||
259 | Sema::LookupOperatorName); | |||
260 | SemaRef.LookupName(Operators, S); | |||
261 | ||||
262 | assert(!Operators.isAmbiguous() && "Operator lookup cannot be ambiguous")((!Operators.isAmbiguous() && "Operator lookup cannot be ambiguous" ) ? static_cast<void> (0) : __assert_fail ("!Operators.isAmbiguous() && \"Operator lookup cannot be ambiguous\"" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaCoroutine.cpp" , 262, __PRETTY_FUNCTION__)); | |||
263 | const auto &Functions = Operators.asUnresolvedSet(); | |||
264 | bool IsOverloaded = | |||
265 | Functions.size() > 1 || | |||
266 | (Functions.size() == 1 && isa<FunctionTemplateDecl>(*Functions.begin())); | |||
267 | Expr *CoawaitOp = UnresolvedLookupExpr::Create( | |||
268 | SemaRef.Context, /*NamingClass*/ nullptr, NestedNameSpecifierLoc(), | |||
269 | DeclarationNameInfo(OpName, Loc), /*RequiresADL*/ true, IsOverloaded, | |||
270 | Functions.begin(), Functions.end()); | |||
271 | assert(CoawaitOp)((CoawaitOp) ? static_cast<void> (0) : __assert_fail ("CoawaitOp" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaCoroutine.cpp" , 271, __PRETTY_FUNCTION__)); | |||
272 | return CoawaitOp; | |||
273 | } | |||
274 | ||||
275 | /// Build a call to 'operator co_await' if there is a suitable operator for | |||
276 | /// the given expression. | |||
277 | static ExprResult buildOperatorCoawaitCall(Sema &SemaRef, SourceLocation Loc, | |||
278 | Expr *E, | |||
279 | UnresolvedLookupExpr *Lookup) { | |||
280 | UnresolvedSet<16> Functions; | |||
281 | Functions.append(Lookup->decls_begin(), Lookup->decls_end()); | |||
282 | return SemaRef.CreateOverloadedUnaryOp(Loc, UO_Coawait, Functions, E); | |||
283 | } | |||
284 | ||||
285 | static ExprResult buildOperatorCoawaitCall(Sema &SemaRef, Scope *S, | |||
286 | SourceLocation Loc, Expr *E) { | |||
287 | ExprResult R = buildOperatorCoawaitLookupExpr(SemaRef, S, Loc); | |||
288 | if (R.isInvalid()) | |||
289 | return ExprError(); | |||
290 | return buildOperatorCoawaitCall(SemaRef, Loc, E, | |||
291 | cast<UnresolvedLookupExpr>(R.get())); | |||
292 | } | |||
293 | ||||
294 | static Expr *buildBuiltinCall(Sema &S, SourceLocation Loc, Builtin::ID Id, | |||
295 | MultiExprArg CallArgs) { | |||
296 | StringRef Name = S.Context.BuiltinInfo.getName(Id); | |||
297 | LookupResult R(S, &S.Context.Idents.get(Name), Loc, Sema::LookupOrdinaryName); | |||
298 | S.LookupName(R, S.TUScope, /*AllowBuiltinCreation=*/true); | |||
299 | ||||
300 | auto *BuiltInDecl = R.getAsSingle<FunctionDecl>(); | |||
301 | assert(BuiltInDecl && "failed to find builtin declaration")((BuiltInDecl && "failed to find builtin declaration" ) ? static_cast<void> (0) : __assert_fail ("BuiltInDecl && \"failed to find builtin declaration\"" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaCoroutine.cpp" , 301, __PRETTY_FUNCTION__)); | |||
302 | ||||
303 | ExprResult DeclRef = | |||
304 | S.BuildDeclRefExpr(BuiltInDecl, BuiltInDecl->getType(), VK_LValue, Loc); | |||
305 | assert(DeclRef.isUsable() && "Builtin reference cannot fail")((DeclRef.isUsable() && "Builtin reference cannot fail" ) ? static_cast<void> (0) : __assert_fail ("DeclRef.isUsable() && \"Builtin reference cannot fail\"" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaCoroutine.cpp" , 305, __PRETTY_FUNCTION__)); | |||
306 | ||||
307 | ExprResult Call = | |||
308 | S.BuildCallExpr(/*Scope=*/nullptr, DeclRef.get(), Loc, CallArgs, Loc); | |||
309 | ||||
310 | assert(!Call.isInvalid() && "Call to builtin cannot fail!")((!Call.isInvalid() && "Call to builtin cannot fail!" ) ? static_cast<void> (0) : __assert_fail ("!Call.isInvalid() && \"Call to builtin cannot fail!\"" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaCoroutine.cpp" , 310, __PRETTY_FUNCTION__)); | |||
311 | return Call.get(); | |||
312 | } | |||
313 | ||||
314 | static ExprResult buildCoroutineHandle(Sema &S, QualType PromiseType, | |||
315 | SourceLocation Loc) { | |||
316 | QualType CoroHandleType = lookupCoroutineHandleType(S, PromiseType, Loc); | |||
317 | if (CoroHandleType.isNull()) | |||
318 | return ExprError(); | |||
319 | ||||
320 | DeclContext *LookupCtx = S.computeDeclContext(CoroHandleType); | |||
321 | LookupResult Found(S, &S.PP.getIdentifierTable().get("from_address"), Loc, | |||
322 | Sema::LookupOrdinaryName); | |||
323 | if (!S.LookupQualifiedName(Found, LookupCtx)) { | |||
324 | S.Diag(Loc, diag::err_coroutine_handle_missing_member) | |||
325 | << "from_address"; | |||
326 | return ExprError(); | |||
327 | } | |||
328 | ||||
329 | Expr *FramePtr = | |||
330 | buildBuiltinCall(S, Loc, Builtin::BI__builtin_coro_frame, {}); | |||
331 | ||||
332 | CXXScopeSpec SS; | |||
333 | ExprResult FromAddr = | |||
334 | S.BuildDeclarationNameExpr(SS, Found, /*NeedsADL=*/false); | |||
335 | if (FromAddr.isInvalid()) | |||
336 | return ExprError(); | |||
337 | ||||
338 | return S.BuildCallExpr(nullptr, FromAddr.get(), Loc, FramePtr, Loc); | |||
339 | } | |||
340 | ||||
341 | struct ReadySuspendResumeResult { | |||
342 | enum AwaitCallType { ACT_Ready, ACT_Suspend, ACT_Resume }; | |||
343 | Expr *Results[3]; | |||
344 | OpaqueValueExpr *OpaqueValue; | |||
345 | bool IsInvalid; | |||
346 | }; | |||
347 | ||||
348 | static ExprResult buildMemberCall(Sema &S, Expr *Base, SourceLocation Loc, | |||
349 | StringRef Name, MultiExprArg Args) { | |||
350 | DeclarationNameInfo NameInfo(&S.PP.getIdentifierTable().get(Name), Loc); | |||
351 | ||||
352 | // FIXME: Fix BuildMemberReferenceExpr to take a const CXXScopeSpec&. | |||
353 | CXXScopeSpec SS; | |||
354 | ExprResult Result = S.BuildMemberReferenceExpr( | |||
355 | Base, Base->getType(), Loc, /*IsPtr=*/false, SS, | |||
356 | SourceLocation(), nullptr, NameInfo, /*TemplateArgs=*/nullptr, | |||
357 | /*Scope=*/nullptr); | |||
358 | if (Result.isInvalid()) | |||
359 | return ExprError(); | |||
360 | ||||
361 | // We meant exactly what we asked for. No need for typo correction. | |||
362 | if (auto *TE = dyn_cast<TypoExpr>(Result.get())) { | |||
363 | S.clearDelayedTypo(TE); | |||
364 | S.Diag(Loc, diag::err_no_member) | |||
365 | << NameInfo.getName() << Base->getType()->getAsCXXRecordDecl() | |||
366 | << Base->getSourceRange(); | |||
367 | return ExprError(); | |||
368 | } | |||
369 | ||||
370 | return S.BuildCallExpr(nullptr, Result.get(), Loc, Args, Loc, nullptr); | |||
371 | } | |||
372 | ||||
373 | // See if return type is coroutine-handle and if so, invoke builtin coro-resume | |||
374 | // on its address. This is to enable experimental support for coroutine-handle | |||
375 | // returning await_suspend that results in a guaranteed tail call to the target | |||
376 | // coroutine. | |||
377 | static Expr *maybeTailCall(Sema &S, QualType RetType, Expr *E, | |||
378 | SourceLocation Loc) { | |||
379 | if (RetType->isReferenceType()) | |||
380 | return nullptr; | |||
381 | Type const *T = RetType.getTypePtr(); | |||
382 | if (!T->isClassType() && !T->isStructureType()) | |||
383 | return nullptr; | |||
384 | ||||
385 | // FIXME: Add convertability check to coroutine_handle<>. Possibly via | |||
386 | // EvaluateBinaryTypeTrait(BTT_IsConvertible, ...) which is at the moment | |||
387 | // a private function in SemaExprCXX.cpp | |||
388 | ||||
389 | ExprResult AddressExpr = buildMemberCall(S, E, Loc, "address", None); | |||
390 | if (AddressExpr.isInvalid()) | |||
391 | return nullptr; | |||
392 | ||||
393 | Expr *JustAddress = AddressExpr.get(); | |||
394 | ||||
395 | // Check that the type of AddressExpr is void* | |||
396 | if (!JustAddress->getType().getTypePtr()->isVoidPointerType()) | |||
397 | S.Diag(cast<CallExpr>(JustAddress)->getCalleeDecl()->getLocation(), | |||
398 | diag::warn_coroutine_handle_address_invalid_return_type) | |||
399 | << JustAddress->getType(); | |||
400 | ||||
401 | // Clean up temporary objects so that they don't live across suspension points | |||
402 | // unnecessarily. We choose to clean up before the call to | |||
403 | // __builtin_coro_resume so that the cleanup code are not inserted in-between | |||
404 | // the resume call and return instruction, which would interfere with the | |||
405 | // musttail call contract. | |||
406 | JustAddress = S.MaybeCreateExprWithCleanups(JustAddress); | |||
407 | return buildBuiltinCall(S, Loc, Builtin::BI__builtin_coro_resume, | |||
408 | JustAddress); | |||
409 | } | |||
410 | ||||
411 | /// Build calls to await_ready, await_suspend, and await_resume for a co_await | |||
412 | /// expression. | |||
413 | /// The generated AST tries to clean up temporary objects as early as | |||
414 | /// possible so that they don't live across suspension points if possible. | |||
415 | /// Having temporary objects living across suspension points unnecessarily can | |||
416 | /// lead to large frame size, and also lead to memory corruptions if the | |||
417 | /// coroutine frame is destroyed after coming back from suspension. This is done | |||
418 | /// by wrapping both the await_ready call and the await_suspend call with | |||
419 | /// ExprWithCleanups. In the end of this function, we also need to explicitly | |||
420 | /// set cleanup state so that the CoawaitExpr is also wrapped with an | |||
421 | /// ExprWithCleanups to clean up the awaiter associated with the co_await | |||
422 | /// expression. | |||
423 | static ReadySuspendResumeResult buildCoawaitCalls(Sema &S, VarDecl *CoroPromise, | |||
424 | SourceLocation Loc, Expr *E) { | |||
425 | OpaqueValueExpr *Operand = new (S.Context) | |||
426 | OpaqueValueExpr(Loc, E->getType(), VK_LValue, E->getObjectKind(), E); | |||
427 | ||||
428 | // Assume valid until we see otherwise. | |||
429 | // Further operations are responsible for setting IsInalid to true. | |||
430 | ReadySuspendResumeResult Calls = {{}, Operand, /*IsInvalid=*/false}; | |||
431 | ||||
432 | using ACT = ReadySuspendResumeResult::AwaitCallType; | |||
433 | ||||
434 | auto BuildSubExpr = [&](ACT CallType, StringRef Func, | |||
435 | MultiExprArg Arg) -> Expr * { | |||
436 | ExprResult Result = buildMemberCall(S, Operand, Loc, Func, Arg); | |||
437 | if (Result.isInvalid()) { | |||
438 | Calls.IsInvalid = true; | |||
439 | return nullptr; | |||
440 | } | |||
441 | Calls.Results[CallType] = Result.get(); | |||
442 | return Result.get(); | |||
443 | }; | |||
444 | ||||
445 | CallExpr *AwaitReady = | |||
446 | cast_or_null<CallExpr>(BuildSubExpr(ACT::ACT_Ready, "await_ready", None)); | |||
447 | if (!AwaitReady) | |||
448 | return Calls; | |||
449 | if (!AwaitReady->getType()->isDependentType()) { | |||
450 | // [expr.await]p3 [...] | |||
451 | // — await-ready is the expression e.await_ready(), contextually converted | |||
452 | // to bool. | |||
453 | ExprResult Conv = S.PerformContextuallyConvertToBool(AwaitReady); | |||
454 | if (Conv.isInvalid()) { | |||
455 | S.Diag(AwaitReady->getDirectCallee()->getBeginLoc(), | |||
456 | diag::note_await_ready_no_bool_conversion); | |||
457 | S.Diag(Loc, diag::note_coroutine_promise_call_implicitly_required) | |||
458 | << AwaitReady->getDirectCallee() << E->getSourceRange(); | |||
459 | Calls.IsInvalid = true; | |||
460 | } else | |||
461 | Calls.Results[ACT::ACT_Ready] = S.MaybeCreateExprWithCleanups(Conv.get()); | |||
462 | } | |||
463 | ||||
464 | ExprResult CoroHandleRes = | |||
465 | buildCoroutineHandle(S, CoroPromise->getType(), Loc); | |||
466 | if (CoroHandleRes.isInvalid()) { | |||
467 | Calls.IsInvalid = true; | |||
468 | return Calls; | |||
469 | } | |||
470 | Expr *CoroHandle = CoroHandleRes.get(); | |||
471 | CallExpr *AwaitSuspend = cast_or_null<CallExpr>( | |||
472 | BuildSubExpr(ACT::ACT_Suspend, "await_suspend", CoroHandle)); | |||
473 | if (!AwaitSuspend) | |||
474 | return Calls; | |||
475 | if (!AwaitSuspend->getType()->isDependentType()) { | |||
476 | // [expr.await]p3 [...] | |||
477 | // - await-suspend is the expression e.await_suspend(h), which shall be | |||
478 | // a prvalue of type void, bool, or std::coroutine_handle<Z> for some | |||
479 | // type Z. | |||
480 | QualType RetType = AwaitSuspend->getCallReturnType(S.Context); | |||
481 | ||||
482 | // Experimental support for coroutine_handle returning await_suspend. | |||
483 | if (Expr *TailCallSuspend = | |||
484 | maybeTailCall(S, RetType, AwaitSuspend, Loc)) | |||
485 | // Note that we don't wrap the expression with ExprWithCleanups here | |||
486 | // because that might interfere with tailcall contract (e.g. inserting | |||
487 | // clean up instructions in-between tailcall and return). Instead | |||
488 | // ExprWithCleanups is wrapped within maybeTailCall() prior to the resume | |||
489 | // call. | |||
490 | Calls.Results[ACT::ACT_Suspend] = TailCallSuspend; | |||
491 | else { | |||
492 | // non-class prvalues always have cv-unqualified types | |||
493 | if (RetType->isReferenceType() || | |||
494 | (!RetType->isBooleanType() && !RetType->isVoidType())) { | |||
495 | S.Diag(AwaitSuspend->getCalleeDecl()->getLocation(), | |||
496 | diag::err_await_suspend_invalid_return_type) | |||
497 | << RetType; | |||
498 | S.Diag(Loc, diag::note_coroutine_promise_call_implicitly_required) | |||
499 | << AwaitSuspend->getDirectCallee(); | |||
500 | Calls.IsInvalid = true; | |||
501 | } else | |||
502 | Calls.Results[ACT::ACT_Suspend] = | |||
503 | S.MaybeCreateExprWithCleanups(AwaitSuspend); | |||
504 | } | |||
505 | } | |||
506 | ||||
507 | BuildSubExpr(ACT::ACT_Resume, "await_resume", None); | |||
508 | ||||
509 | // Make sure the awaiter object gets a chance to be cleaned up. | |||
510 | S.Cleanup.setExprNeedsCleanups(true); | |||
511 | ||||
512 | return Calls; | |||
513 | } | |||
514 | ||||
515 | static ExprResult buildPromiseCall(Sema &S, VarDecl *Promise, | |||
516 | SourceLocation Loc, StringRef Name, | |||
517 | MultiExprArg Args) { | |||
518 | ||||
519 | // Form a reference to the promise. | |||
520 | ExprResult PromiseRef = S.BuildDeclRefExpr( | |||
521 | Promise, Promise->getType().getNonReferenceType(), VK_LValue, Loc); | |||
522 | if (PromiseRef.isInvalid()) | |||
523 | return ExprError(); | |||
524 | ||||
525 | return buildMemberCall(S, PromiseRef.get(), Loc, Name, Args); | |||
526 | } | |||
527 | ||||
528 | VarDecl *Sema::buildCoroutinePromise(SourceLocation Loc) { | |||
529 | assert(isa<FunctionDecl>(CurContext) && "not in a function scope")((isa<FunctionDecl>(CurContext) && "not in a function scope" ) ? static_cast<void> (0) : __assert_fail ("isa<FunctionDecl>(CurContext) && \"not in a function scope\"" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaCoroutine.cpp" , 529, __PRETTY_FUNCTION__)); | |||
530 | auto *FD = cast<FunctionDecl>(CurContext); | |||
531 | bool IsThisDependentType = [&] { | |||
532 | if (auto *MD = dyn_cast_or_null<CXXMethodDecl>(FD)) | |||
533 | return MD->isInstance() && MD->getThisType()->isDependentType(); | |||
534 | else | |||
535 | return false; | |||
536 | }(); | |||
537 | ||||
538 | QualType T = FD->getType()->isDependentType() || IsThisDependentType | |||
539 | ? Context.DependentTy | |||
540 | : lookupPromiseType(*this, FD, Loc); | |||
541 | if (T.isNull()) | |||
542 | return nullptr; | |||
543 | ||||
544 | auto *VD = VarDecl::Create(Context, FD, FD->getLocation(), FD->getLocation(), | |||
545 | &PP.getIdentifierTable().get("__promise"), T, | |||
546 | Context.getTrivialTypeSourceInfo(T, Loc), SC_None); | |||
547 | VD->setImplicit(); | |||
548 | CheckVariableDeclarationType(VD); | |||
549 | if (VD->isInvalidDecl()) | |||
550 | return nullptr; | |||
551 | ||||
552 | auto *ScopeInfo = getCurFunction(); | |||
553 | ||||
554 | // Build a list of arguments, based on the coroutine function's arguments, | |||
555 | // that if present will be passed to the promise type's constructor. | |||
556 | llvm::SmallVector<Expr *, 4> CtorArgExprs; | |||
557 | ||||
558 | // Add implicit object parameter. | |||
559 | if (auto *MD = dyn_cast<CXXMethodDecl>(FD)) { | |||
560 | if (MD->isInstance() && !isLambdaCallOperator(MD)) { | |||
561 | ExprResult ThisExpr = ActOnCXXThis(Loc); | |||
562 | if (ThisExpr.isInvalid()) | |||
563 | return nullptr; | |||
564 | ThisExpr = CreateBuiltinUnaryOp(Loc, UO_Deref, ThisExpr.get()); | |||
565 | if (ThisExpr.isInvalid()) | |||
566 | return nullptr; | |||
567 | CtorArgExprs.push_back(ThisExpr.get()); | |||
568 | } | |||
569 | } | |||
570 | ||||
571 | // Add the coroutine function's parameters. | |||
572 | auto &Moves = ScopeInfo->CoroutineParameterMoves; | |||
573 | for (auto *PD : FD->parameters()) { | |||
574 | if (PD->getType()->isDependentType()) | |||
575 | continue; | |||
576 | ||||
577 | auto RefExpr = ExprEmpty(); | |||
578 | auto Move = Moves.find(PD); | |||
579 | assert(Move != Moves.end() &&((Move != Moves.end() && "Coroutine function parameter not inserted into move map" ) ? static_cast<void> (0) : __assert_fail ("Move != Moves.end() && \"Coroutine function parameter not inserted into move map\"" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaCoroutine.cpp" , 580, __PRETTY_FUNCTION__)) | |||
580 | "Coroutine function parameter not inserted into move map")((Move != Moves.end() && "Coroutine function parameter not inserted into move map" ) ? static_cast<void> (0) : __assert_fail ("Move != Moves.end() && \"Coroutine function parameter not inserted into move map\"" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaCoroutine.cpp" , 580, __PRETTY_FUNCTION__)); | |||
581 | // If a reference to the function parameter exists in the coroutine | |||
582 | // frame, use that reference. | |||
583 | auto *MoveDecl = | |||
584 | cast<VarDecl>(cast<DeclStmt>(Move->second)->getSingleDecl()); | |||
585 | RefExpr = | |||
586 | BuildDeclRefExpr(MoveDecl, MoveDecl->getType().getNonReferenceType(), | |||
587 | ExprValueKind::VK_LValue, FD->getLocation()); | |||
588 | if (RefExpr.isInvalid()) | |||
589 | return nullptr; | |||
590 | CtorArgExprs.push_back(RefExpr.get()); | |||
591 | } | |||
592 | ||||
593 | // If we have a non-zero number of constructor arguments, try to use them. | |||
594 | // Otherwise, fall back to the promise type's default constructor. | |||
595 | if (!CtorArgExprs.empty()) { | |||
596 | // Create an initialization sequence for the promise type using the | |||
597 | // constructor arguments, wrapped in a parenthesized list expression. | |||
598 | Expr *PLE = ParenListExpr::Create(Context, FD->getLocation(), | |||
599 | CtorArgExprs, FD->getLocation()); | |||
600 | InitializedEntity Entity = InitializedEntity::InitializeVariable(VD); | |||
601 | InitializationKind Kind = InitializationKind::CreateForInit( | |||
602 | VD->getLocation(), /*DirectInit=*/true, PLE); | |||
603 | InitializationSequence InitSeq(*this, Entity, Kind, CtorArgExprs, | |||
604 | /*TopLevelOfInitList=*/false, | |||
605 | /*TreatUnavailableAsInvalid=*/false); | |||
606 | ||||
607 | // Attempt to initialize the promise type with the arguments. | |||
608 | // If that fails, fall back to the promise type's default constructor. | |||
609 | if (InitSeq) { | |||
610 | ExprResult Result = InitSeq.Perform(*this, Entity, Kind, CtorArgExprs); | |||
611 | if (Result.isInvalid()) { | |||
612 | VD->setInvalidDecl(); | |||
613 | } else if (Result.get()) { | |||
614 | VD->setInit(MaybeCreateExprWithCleanups(Result.get())); | |||
615 | VD->setInitStyle(VarDecl::CallInit); | |||
616 | CheckCompleteVariableDeclaration(VD); | |||
617 | } | |||
618 | } else | |||
619 | ActOnUninitializedDecl(VD); | |||
620 | } else | |||
621 | ActOnUninitializedDecl(VD); | |||
622 | ||||
623 | FD->addDecl(VD); | |||
624 | return VD; | |||
625 | } | |||
626 | ||||
627 | /// Check that this is a context in which a coroutine suspension can appear. | |||
628 | static FunctionScopeInfo *checkCoroutineContext(Sema &S, SourceLocation Loc, | |||
629 | StringRef Keyword, | |||
630 | bool IsImplicit = false) { | |||
631 | if (!isValidCoroutineContext(S, Loc, Keyword)) | |||
632 | return nullptr; | |||
633 | ||||
634 | assert(isa<FunctionDecl>(S.CurContext) && "not in a function scope")((isa<FunctionDecl>(S.CurContext) && "not in a function scope" ) ? static_cast<void> (0) : __assert_fail ("isa<FunctionDecl>(S.CurContext) && \"not in a function scope\"" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaCoroutine.cpp" , 634, __PRETTY_FUNCTION__)); | |||
635 | ||||
636 | auto *ScopeInfo = S.getCurFunction(); | |||
637 | assert(ScopeInfo && "missing function scope for function")((ScopeInfo && "missing function scope for function") ? static_cast<void> (0) : __assert_fail ("ScopeInfo && \"missing function scope for function\"" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaCoroutine.cpp" , 637, __PRETTY_FUNCTION__)); | |||
638 | ||||
639 | if (ScopeInfo->FirstCoroutineStmtLoc.isInvalid() && !IsImplicit) | |||
640 | ScopeInfo->setFirstCoroutineStmt(Loc, Keyword); | |||
641 | ||||
642 | if (ScopeInfo->CoroutinePromise) | |||
643 | return ScopeInfo; | |||
644 | ||||
645 | if (!S.buildCoroutineParameterMoves(Loc)) | |||
646 | return nullptr; | |||
647 | ||||
648 | ScopeInfo->CoroutinePromise = S.buildCoroutinePromise(Loc); | |||
649 | if (!ScopeInfo->CoroutinePromise) | |||
650 | return nullptr; | |||
651 | ||||
652 | return ScopeInfo; | |||
653 | } | |||
654 | ||||
655 | /// Recursively check \p E and all its children to see if any call target | |||
656 | /// (including constructor call) is declared noexcept. Also any value returned | |||
657 | /// from the call has a noexcept destructor. | |||
658 | static void checkNoThrow(Sema &S, const Stmt *E, | |||
659 | llvm::SmallPtrSetImpl<const Decl *> &ThrowingDecls) { | |||
660 | auto checkDeclNoexcept = [&](const Decl *D, bool IsDtor = false) { | |||
661 | // In the case of dtor, the call to dtor is implicit and hence we should | |||
662 | // pass nullptr to canCalleeThrow. | |||
663 | if (Sema::canCalleeThrow(S, IsDtor ? nullptr : cast<Expr>(E), D)) { | |||
664 | if (const auto *FD = dyn_cast<FunctionDecl>(D)) { | |||
665 | // co_await promise.final_suspend() could end up calling | |||
666 | // __builtin_coro_resume for symmetric transfer if await_suspend() | |||
667 | // returns a handle. In that case, even __builtin_coro_resume is not | |||
668 | // declared as noexcept and may throw, it does not throw _into_ the | |||
669 | // coroutine that just suspended, but rather throws back out from | |||
670 | // whoever called coroutine_handle::resume(), hence we claim that | |||
671 | // logically it does not throw. | |||
672 | if (FD->getBuiltinID() == Builtin::BI__builtin_coro_resume) | |||
673 | return; | |||
674 | } | |||
675 | if (ThrowingDecls.empty()) { | |||
676 | // First time seeing an error, emit the error message. | |||
677 | S.Diag(cast<FunctionDecl>(S.CurContext)->getLocation(), | |||
678 | diag::err_coroutine_promise_final_suspend_requires_nothrow); | |||
679 | } | |||
680 | ThrowingDecls.insert(D); | |||
681 | } | |||
682 | }; | |||
683 | auto SC = E->getStmtClass(); | |||
684 | if (SC == Expr::CXXConstructExprClass) { | |||
685 | auto const *Ctor = cast<CXXConstructExpr>(E)->getConstructor(); | |||
686 | checkDeclNoexcept(Ctor); | |||
687 | // Check the corresponding destructor of the constructor. | |||
688 | checkDeclNoexcept(Ctor->getParent()->getDestructor(), true); | |||
689 | } else if (SC == Expr::CallExprClass || SC == Expr::CXXMemberCallExprClass || | |||
690 | SC == Expr::CXXOperatorCallExprClass) { | |||
691 | if (!cast<CallExpr>(E)->isTypeDependent()) { | |||
692 | checkDeclNoexcept(cast<CallExpr>(E)->getCalleeDecl()); | |||
693 | auto ReturnType = cast<CallExpr>(E)->getCallReturnType(S.getASTContext()); | |||
694 | // Check the destructor of the call return type, if any. | |||
695 | if (ReturnType.isDestructedType() == | |||
696 | QualType::DestructionKind::DK_cxx_destructor) { | |||
697 | const auto *T = | |||
698 | cast<RecordType>(ReturnType.getCanonicalType().getTypePtr()); | |||
699 | checkDeclNoexcept( | |||
700 | dyn_cast<CXXRecordDecl>(T->getDecl())->getDestructor(), true); | |||
| ||||
701 | } | |||
702 | } | |||
703 | } | |||
704 | for (const auto *Child : E->children()) { | |||
705 | if (!Child) | |||
706 | continue; | |||
707 | checkNoThrow(S, Child, ThrowingDecls); | |||
708 | } | |||
709 | } | |||
710 | ||||
711 | bool Sema::checkFinalSuspendNoThrow(const Stmt *FinalSuspend) { | |||
712 | llvm::SmallPtrSet<const Decl *, 4> ThrowingDecls; | |||
713 | // We first collect all declarations that should not throw but not declared | |||
714 | // with noexcept. We then sort them based on the location before printing. | |||
715 | // This is to avoid emitting the same note multiple times on the same | |||
716 | // declaration, and also provide a deterministic order for the messages. | |||
717 | checkNoThrow(*this, FinalSuspend, ThrowingDecls); | |||
718 | auto SortedDecls = llvm::SmallVector<const Decl *, 4>{ThrowingDecls.begin(), | |||
719 | ThrowingDecls.end()}; | |||
720 | sort(SortedDecls, [](const Decl *A, const Decl *B) { | |||
721 | return A->getEndLoc() < B->getEndLoc(); | |||
722 | }); | |||
723 | for (const auto *D : SortedDecls) { | |||
724 | Diag(D->getEndLoc(), diag::note_coroutine_function_declare_noexcept); | |||
725 | } | |||
726 | return ThrowingDecls.empty(); | |||
727 | } | |||
728 | ||||
729 | bool Sema::ActOnCoroutineBodyStart(Scope *SC, SourceLocation KWLoc, | |||
730 | StringRef Keyword) { | |||
731 | if (!checkCoroutineContext(*this, KWLoc, Keyword)) | |||
732 | return false; | |||
733 | auto *ScopeInfo = getCurFunction(); | |||
734 | assert(ScopeInfo->CoroutinePromise)((ScopeInfo->CoroutinePromise) ? static_cast<void> ( 0) : __assert_fail ("ScopeInfo->CoroutinePromise", "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaCoroutine.cpp" , 734, __PRETTY_FUNCTION__)); | |||
735 | ||||
736 | // If we have existing coroutine statements then we have already built | |||
737 | // the initial and final suspend points. | |||
738 | if (!ScopeInfo->NeedsCoroutineSuspends) | |||
739 | return true; | |||
740 | ||||
741 | ScopeInfo->setNeedsCoroutineSuspends(false); | |||
742 | ||||
743 | auto *Fn = cast<FunctionDecl>(CurContext); | |||
744 | SourceLocation Loc = Fn->getLocation(); | |||
745 | // Build the initial suspend point | |||
746 | auto buildSuspends = [&](StringRef Name) mutable -> StmtResult { | |||
747 | ExprResult Suspend = | |||
748 | buildPromiseCall(*this, ScopeInfo->CoroutinePromise, Loc, Name, None); | |||
749 | if (Suspend.isInvalid()) | |||
750 | return StmtError(); | |||
751 | Suspend = buildOperatorCoawaitCall(*this, SC, Loc, Suspend.get()); | |||
752 | if (Suspend.isInvalid()) | |||
753 | return StmtError(); | |||
754 | Suspend = BuildResolvedCoawaitExpr(Loc, Suspend.get(), | |||
755 | /*IsImplicit*/ true); | |||
756 | Suspend = ActOnFinishFullExpr(Suspend.get(), /*DiscardedValue*/ false); | |||
757 | if (Suspend.isInvalid()) { | |||
758 | Diag(Loc, diag::note_coroutine_promise_suspend_implicitly_required) | |||
759 | << ((Name == "initial_suspend") ? 0 : 1); | |||
760 | Diag(KWLoc, diag::note_declared_coroutine_here) << Keyword; | |||
761 | return StmtError(); | |||
762 | } | |||
763 | return cast<Stmt>(Suspend.get()); | |||
764 | }; | |||
765 | ||||
766 | StmtResult InitSuspend = buildSuspends("initial_suspend"); | |||
767 | if (InitSuspend.isInvalid()) | |||
768 | return true; | |||
769 | ||||
770 | StmtResult FinalSuspend = buildSuspends("final_suspend"); | |||
771 | if (FinalSuspend.isInvalid() || !checkFinalSuspendNoThrow(FinalSuspend.get())) | |||
772 | return true; | |||
773 | ||||
774 | ScopeInfo->setCoroutineSuspends(InitSuspend.get(), FinalSuspend.get()); | |||
775 | ||||
776 | return true; | |||
777 | } | |||
778 | ||||
779 | // Recursively walks up the scope hierarchy until either a 'catch' or a function | |||
780 | // scope is found, whichever comes first. | |||
781 | static bool isWithinCatchScope(Scope *S) { | |||
782 | // 'co_await' and 'co_yield' keywords are disallowed within catch blocks, but | |||
783 | // lambdas that use 'co_await' are allowed. The loop below ends when a | |||
784 | // function scope is found in order to ensure the following behavior: | |||
785 | // | |||
786 | // void foo() { // <- function scope | |||
787 | // try { // | |||
788 | // co_await x; // <- 'co_await' is OK within a function scope | |||
789 | // } catch { // <- catch scope | |||
790 | // co_await x; // <- 'co_await' is not OK within a catch scope | |||
791 | // []() { // <- function scope | |||
792 | // co_await x; // <- 'co_await' is OK within a function scope | |||
793 | // }(); | |||
794 | // } | |||
795 | // } | |||
796 | while (S && !(S->getFlags() & Scope::FnScope)) { | |||
797 | if (S->getFlags() & Scope::CatchScope) | |||
798 | return true; | |||
799 | S = S->getParent(); | |||
800 | } | |||
801 | return false; | |||
802 | } | |||
803 | ||||
804 | // [expr.await]p2, emphasis added: "An await-expression shall appear only in | |||
805 | // a *potentially evaluated* expression within the compound-statement of a | |||
806 | // function-body *outside of a handler* [...] A context within a function | |||
807 | // where an await-expression can appear is called a suspension context of the | |||
808 | // function." | |||
809 | static void checkSuspensionContext(Sema &S, SourceLocation Loc, | |||
810 | StringRef Keyword) { | |||
811 | // First emphasis of [expr.await]p2: must be a potentially evaluated context. | |||
812 | // That is, 'co_await' and 'co_yield' cannot appear in subexpressions of | |||
813 | // \c sizeof. | |||
814 | if (S.isUnevaluatedContext()) | |||
815 | S.Diag(Loc, diag::err_coroutine_unevaluated_context) << Keyword; | |||
816 | ||||
817 | // Second emphasis of [expr.await]p2: must be outside of an exception handler. | |||
818 | if (isWithinCatchScope(S.getCurScope())) | |||
819 | S.Diag(Loc, diag::err_coroutine_within_handler) << Keyword; | |||
820 | } | |||
821 | ||||
822 | ExprResult Sema::ActOnCoawaitExpr(Scope *S, SourceLocation Loc, Expr *E) { | |||
823 | if (!ActOnCoroutineBodyStart(S, Loc, "co_await")) { | |||
824 | CorrectDelayedTyposInExpr(E); | |||
825 | return ExprError(); | |||
826 | } | |||
827 | ||||
828 | checkSuspensionContext(*this, Loc, "co_await"); | |||
829 | ||||
830 | if (E->getType()->isPlaceholderType()) { | |||
831 | ExprResult R = CheckPlaceholderExpr(E); | |||
832 | if (R.isInvalid()) return ExprError(); | |||
833 | E = R.get(); | |||
834 | } | |||
835 | ExprResult Lookup = buildOperatorCoawaitLookupExpr(*this, S, Loc); | |||
836 | if (Lookup.isInvalid()) | |||
837 | return ExprError(); | |||
838 | return BuildUnresolvedCoawaitExpr(Loc, E, | |||
839 | cast<UnresolvedLookupExpr>(Lookup.get())); | |||
840 | } | |||
841 | ||||
842 | ExprResult Sema::BuildUnresolvedCoawaitExpr(SourceLocation Loc, Expr *E, | |||
843 | UnresolvedLookupExpr *Lookup) { | |||
844 | auto *FSI = checkCoroutineContext(*this, Loc, "co_await"); | |||
845 | if (!FSI) | |||
846 | return ExprError(); | |||
847 | ||||
848 | if (E->getType()->isPlaceholderType()) { | |||
849 | ExprResult R = CheckPlaceholderExpr(E); | |||
850 | if (R.isInvalid()) | |||
851 | return ExprError(); | |||
852 | E = R.get(); | |||
853 | } | |||
854 | ||||
855 | auto *Promise = FSI->CoroutinePromise; | |||
856 | if (Promise->getType()->isDependentType()) { | |||
857 | Expr *Res = | |||
858 | new (Context) DependentCoawaitExpr(Loc, Context.DependentTy, E, Lookup); | |||
859 | return Res; | |||
860 | } | |||
861 | ||||
862 | auto *RD = Promise->getType()->getAsCXXRecordDecl(); | |||
863 | if (lookupMember(*this, "await_transform", RD, Loc)) { | |||
864 | ExprResult R = buildPromiseCall(*this, Promise, Loc, "await_transform", E); | |||
865 | if (R.isInvalid()) { | |||
866 | Diag(Loc, | |||
867 | diag::note_coroutine_promise_implicit_await_transform_required_here) | |||
868 | << E->getSourceRange(); | |||
869 | return ExprError(); | |||
870 | } | |||
871 | E = R.get(); | |||
872 | } | |||
873 | ExprResult Awaitable = buildOperatorCoawaitCall(*this, Loc, E, Lookup); | |||
874 | if (Awaitable.isInvalid()) | |||
875 | return ExprError(); | |||
876 | ||||
877 | return BuildResolvedCoawaitExpr(Loc, Awaitable.get()); | |||
878 | } | |||
879 | ||||
880 | ExprResult Sema::BuildResolvedCoawaitExpr(SourceLocation Loc, Expr *E, | |||
881 | bool IsImplicit) { | |||
882 | auto *Coroutine = checkCoroutineContext(*this, Loc, "co_await", IsImplicit); | |||
883 | if (!Coroutine) | |||
884 | return ExprError(); | |||
885 | ||||
886 | if (E->getType()->isPlaceholderType()) { | |||
887 | ExprResult R = CheckPlaceholderExpr(E); | |||
888 | if (R.isInvalid()) return ExprError(); | |||
889 | E = R.get(); | |||
890 | } | |||
891 | ||||
892 | if (E->getType()->isDependentType()) { | |||
893 | Expr *Res = new (Context) | |||
894 | CoawaitExpr(Loc, Context.DependentTy, E, IsImplicit); | |||
895 | return Res; | |||
896 | } | |||
897 | ||||
898 | // If the expression is a temporary, materialize it as an lvalue so that we | |||
899 | // can use it multiple times. | |||
900 | if (E->getValueKind() == VK_RValue) | |||
901 | E = CreateMaterializeTemporaryExpr(E->getType(), E, true); | |||
902 | ||||
903 | // The location of the `co_await` token cannot be used when constructing | |||
904 | // the member call expressions since it's before the location of `Expr`, which | |||
905 | // is used as the start of the member call expression. | |||
906 | SourceLocation CallLoc = E->getExprLoc(); | |||
907 | ||||
908 | // Build the await_ready, await_suspend, await_resume calls. | |||
909 | ReadySuspendResumeResult RSS = buildCoawaitCalls( | |||
910 | *this, Coroutine->CoroutinePromise, CallLoc, E); | |||
911 | if (RSS.IsInvalid) | |||
912 | return ExprError(); | |||
913 | ||||
914 | Expr *Res = | |||
915 | new (Context) CoawaitExpr(Loc, E, RSS.Results[0], RSS.Results[1], | |||
916 | RSS.Results[2], RSS.OpaqueValue, IsImplicit); | |||
917 | ||||
918 | return Res; | |||
919 | } | |||
920 | ||||
921 | ExprResult Sema::ActOnCoyieldExpr(Scope *S, SourceLocation Loc, Expr *E) { | |||
922 | if (!ActOnCoroutineBodyStart(S, Loc, "co_yield")) { | |||
923 | CorrectDelayedTyposInExpr(E); | |||
924 | return ExprError(); | |||
925 | } | |||
926 | ||||
927 | checkSuspensionContext(*this, Loc, "co_yield"); | |||
928 | ||||
929 | // Build yield_value call. | |||
930 | ExprResult Awaitable = buildPromiseCall( | |||
931 | *this, getCurFunction()->CoroutinePromise, Loc, "yield_value", E); | |||
932 | if (Awaitable.isInvalid()) | |||
933 | return ExprError(); | |||
934 | ||||
935 | // Build 'operator co_await' call. | |||
936 | Awaitable = buildOperatorCoawaitCall(*this, S, Loc, Awaitable.get()); | |||
937 | if (Awaitable.isInvalid()) | |||
938 | return ExprError(); | |||
939 | ||||
940 | return BuildCoyieldExpr(Loc, Awaitable.get()); | |||
941 | } | |||
942 | ExprResult Sema::BuildCoyieldExpr(SourceLocation Loc, Expr *E) { | |||
943 | auto *Coroutine = checkCoroutineContext(*this, Loc, "co_yield"); | |||
944 | if (!Coroutine) | |||
945 | return ExprError(); | |||
946 | ||||
947 | if (E->getType()->isPlaceholderType()) { | |||
948 | ExprResult R = CheckPlaceholderExpr(E); | |||
949 | if (R.isInvalid()) return ExprError(); | |||
950 | E = R.get(); | |||
951 | } | |||
952 | ||||
953 | if (E->getType()->isDependentType()) { | |||
954 | Expr *Res = new (Context) CoyieldExpr(Loc, Context.DependentTy, E); | |||
955 | return Res; | |||
956 | } | |||
957 | ||||
958 | // If the expression is a temporary, materialize it as an lvalue so that we | |||
959 | // can use it multiple times. | |||
960 | if (E->getValueKind() == VK_RValue) | |||
961 | E = CreateMaterializeTemporaryExpr(E->getType(), E, true); | |||
962 | ||||
963 | // Build the await_ready, await_suspend, await_resume calls. | |||
964 | ReadySuspendResumeResult RSS = buildCoawaitCalls( | |||
965 | *this, Coroutine->CoroutinePromise, Loc, E); | |||
966 | if (RSS.IsInvalid) | |||
967 | return ExprError(); | |||
968 | ||||
969 | Expr *Res = | |||
970 | new (Context) CoyieldExpr(Loc, E, RSS.Results[0], RSS.Results[1], | |||
971 | RSS.Results[2], RSS.OpaqueValue); | |||
972 | ||||
973 | return Res; | |||
974 | } | |||
975 | ||||
976 | StmtResult Sema::ActOnCoreturnStmt(Scope *S, SourceLocation Loc, Expr *E) { | |||
977 | if (!ActOnCoroutineBodyStart(S, Loc, "co_return")) { | |||
| ||||
978 | CorrectDelayedTyposInExpr(E); | |||
979 | return StmtError(); | |||
980 | } | |||
981 | return BuildCoreturnStmt(Loc, E); | |||
982 | } | |||
983 | ||||
984 | StmtResult Sema::BuildCoreturnStmt(SourceLocation Loc, Expr *E, | |||
985 | bool IsImplicit) { | |||
986 | auto *FSI = checkCoroutineContext(*this, Loc, "co_return", IsImplicit); | |||
987 | if (!FSI) | |||
988 | return StmtError(); | |||
989 | ||||
990 | if (E && E->getType()->isPlaceholderType() && | |||
991 | !E->getType()->isSpecificPlaceholderType(BuiltinType::Overload)) { | |||
992 | ExprResult R = CheckPlaceholderExpr(E); | |||
993 | if (R.isInvalid()) return StmtError(); | |||
994 | E = R.get(); | |||
995 | } | |||
996 | ||||
997 | // Move the return value if we can | |||
998 | if (E) { | |||
999 | auto NRVOCandidate = this->getCopyElisionCandidate(E->getType(), E, CES_AsIfByStdMove); | |||
1000 | if (NRVOCandidate) { | |||
1001 | InitializedEntity Entity = | |||
1002 | InitializedEntity::InitializeResult(Loc, E->getType(), NRVOCandidate); | |||
1003 | ExprResult MoveResult = this->PerformMoveOrCopyInitialization( | |||
1004 | Entity, NRVOCandidate, E->getType(), E); | |||
1005 | if (MoveResult.get()) | |||
1006 | E = MoveResult.get(); | |||
1007 | } | |||
1008 | } | |||
1009 | ||||
1010 | // FIXME: If the operand is a reference to a variable that's about to go out | |||
1011 | // of scope, we should treat the operand as an xvalue for this overload | |||
1012 | // resolution. | |||
1013 | VarDecl *Promise = FSI->CoroutinePromise; | |||
1014 | ExprResult PC; | |||
1015 | if (E && (isa<InitListExpr>(E) || !E->getType()->isVoidType())) { | |||
1016 | PC = buildPromiseCall(*this, Promise, Loc, "return_value", E); | |||
1017 | } else { | |||
1018 | E = MakeFullDiscardedValueExpr(E).get(); | |||
1019 | PC = buildPromiseCall(*this, Promise, Loc, "return_void", None); | |||
1020 | } | |||
1021 | if (PC.isInvalid()) | |||
1022 | return StmtError(); | |||
1023 | ||||
1024 | Expr *PCE = ActOnFinishFullExpr(PC.get(), /*DiscardedValue*/ false).get(); | |||
1025 | ||||
1026 | Stmt *Res = new (Context) CoreturnStmt(Loc, E, PCE, IsImplicit); | |||
1027 | return Res; | |||
1028 | } | |||
1029 | ||||
1030 | /// Look up the std::nothrow object. | |||
1031 | static Expr *buildStdNoThrowDeclRef(Sema &S, SourceLocation Loc) { | |||
1032 | NamespaceDecl *Std = S.getStdNamespace(); | |||
1033 | assert(Std && "Should already be diagnosed")((Std && "Should already be diagnosed") ? static_cast <void> (0) : __assert_fail ("Std && \"Should already be diagnosed\"" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaCoroutine.cpp" , 1033, __PRETTY_FUNCTION__)); | |||
1034 | ||||
1035 | LookupResult Result(S, &S.PP.getIdentifierTable().get("nothrow"), Loc, | |||
1036 | Sema::LookupOrdinaryName); | |||
1037 | if (!S.LookupQualifiedName(Result, Std)) { | |||
1038 | // FIXME: <experimental/coroutine> should have been included already. | |||
1039 | // If we require it to include <new> then this diagnostic is no longer | |||
1040 | // needed. | |||
1041 | S.Diag(Loc, diag::err_implicit_coroutine_std_nothrow_type_not_found); | |||
1042 | return nullptr; | |||
1043 | } | |||
1044 | ||||
1045 | auto *VD = Result.getAsSingle<VarDecl>(); | |||
1046 | if (!VD) { | |||
1047 | Result.suppressDiagnostics(); | |||
1048 | // We found something weird. Complain about the first thing we found. | |||
1049 | NamedDecl *Found = *Result.begin(); | |||
1050 | S.Diag(Found->getLocation(), diag::err_malformed_std_nothrow); | |||
1051 | return nullptr; | |||
1052 | } | |||
1053 | ||||
1054 | ExprResult DR = S.BuildDeclRefExpr(VD, VD->getType(), VK_LValue, Loc); | |||
1055 | if (DR.isInvalid()) | |||
1056 | return nullptr; | |||
1057 | ||||
1058 | return DR.get(); | |||
1059 | } | |||
1060 | ||||
1061 | // Find an appropriate delete for the promise. | |||
1062 | static FunctionDecl *findDeleteForPromise(Sema &S, SourceLocation Loc, | |||
1063 | QualType PromiseType) { | |||
1064 | FunctionDecl *OperatorDelete = nullptr; | |||
1065 | ||||
1066 | DeclarationName DeleteName = | |||
1067 | S.Context.DeclarationNames.getCXXOperatorName(OO_Delete); | |||
1068 | ||||
1069 | auto *PointeeRD = PromiseType->getAsCXXRecordDecl(); | |||
1070 | assert(PointeeRD && "PromiseType must be a CxxRecordDecl type")((PointeeRD && "PromiseType must be a CxxRecordDecl type" ) ? static_cast<void> (0) : __assert_fail ("PointeeRD && \"PromiseType must be a CxxRecordDecl type\"" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaCoroutine.cpp" , 1070, __PRETTY_FUNCTION__)); | |||
1071 | ||||
1072 | if (S.FindDeallocationFunction(Loc, PointeeRD, DeleteName, OperatorDelete)) | |||
1073 | return nullptr; | |||
1074 | ||||
1075 | if (!OperatorDelete) { | |||
1076 | // Look for a global declaration. | |||
1077 | const bool CanProvideSize = S.isCompleteType(Loc, PromiseType); | |||
1078 | const bool Overaligned = false; | |||
1079 | OperatorDelete = S.FindUsualDeallocationFunction(Loc, CanProvideSize, | |||
1080 | Overaligned, DeleteName); | |||
1081 | } | |||
1082 | S.MarkFunctionReferenced(Loc, OperatorDelete); | |||
1083 | return OperatorDelete; | |||
1084 | } | |||
1085 | ||||
1086 | ||||
1087 | void Sema::CheckCompletedCoroutineBody(FunctionDecl *FD, Stmt *&Body) { | |||
1088 | FunctionScopeInfo *Fn = getCurFunction(); | |||
1089 | assert(Fn && Fn->isCoroutine() && "not a coroutine")((Fn && Fn->isCoroutine() && "not a coroutine" ) ? static_cast<void> (0) : __assert_fail ("Fn && Fn->isCoroutine() && \"not a coroutine\"" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaCoroutine.cpp" , 1089, __PRETTY_FUNCTION__)); | |||
1090 | if (!Body) { | |||
1091 | assert(FD->isInvalidDecl() &&((FD->isInvalidDecl() && "a null body is only allowed for invalid declarations" ) ? static_cast<void> (0) : __assert_fail ("FD->isInvalidDecl() && \"a null body is only allowed for invalid declarations\"" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaCoroutine.cpp" , 1092, __PRETTY_FUNCTION__)) | |||
1092 | "a null body is only allowed for invalid declarations")((FD->isInvalidDecl() && "a null body is only allowed for invalid declarations" ) ? static_cast<void> (0) : __assert_fail ("FD->isInvalidDecl() && \"a null body is only allowed for invalid declarations\"" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaCoroutine.cpp" , 1092, __PRETTY_FUNCTION__)); | |||
1093 | return; | |||
1094 | } | |||
1095 | // We have a function that uses coroutine keywords, but we failed to build | |||
1096 | // the promise type. | |||
1097 | if (!Fn->CoroutinePromise) | |||
1098 | return FD->setInvalidDecl(); | |||
1099 | ||||
1100 | if (isa<CoroutineBodyStmt>(Body)) { | |||
1101 | // Nothing todo. the body is already a transformed coroutine body statement. | |||
1102 | return; | |||
1103 | } | |||
1104 | ||||
1105 | // Coroutines [stmt.return]p1: | |||
1106 | // A return statement shall not appear in a coroutine. | |||
1107 | if (Fn->FirstReturnLoc.isValid()) { | |||
1108 | assert(Fn->FirstCoroutineStmtLoc.isValid() &&((Fn->FirstCoroutineStmtLoc.isValid() && "first coroutine location not set" ) ? static_cast<void> (0) : __assert_fail ("Fn->FirstCoroutineStmtLoc.isValid() && \"first coroutine location not set\"" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaCoroutine.cpp" , 1109, __PRETTY_FUNCTION__)) | |||
1109 | "first coroutine location not set")((Fn->FirstCoroutineStmtLoc.isValid() && "first coroutine location not set" ) ? static_cast<void> (0) : __assert_fail ("Fn->FirstCoroutineStmtLoc.isValid() && \"first coroutine location not set\"" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaCoroutine.cpp" , 1109, __PRETTY_FUNCTION__)); | |||
1110 | Diag(Fn->FirstReturnLoc, diag::err_return_in_coroutine); | |||
1111 | Diag(Fn->FirstCoroutineStmtLoc, diag::note_declared_coroutine_here) | |||
1112 | << Fn->getFirstCoroutineStmtKeyword(); | |||
1113 | } | |||
1114 | CoroutineStmtBuilder Builder(*this, *FD, *Fn, Body); | |||
1115 | if (Builder.isInvalid() || !Builder.buildStatements()) | |||
1116 | return FD->setInvalidDecl(); | |||
1117 | ||||
1118 | // Build body for the coroutine wrapper statement. | |||
1119 | Body = CoroutineBodyStmt::Create(Context, Builder); | |||
1120 | } | |||
1121 | ||||
1122 | CoroutineStmtBuilder::CoroutineStmtBuilder(Sema &S, FunctionDecl &FD, | |||
1123 | sema::FunctionScopeInfo &Fn, | |||
1124 | Stmt *Body) | |||
1125 | : S(S), FD(FD), Fn(Fn), Loc(FD.getLocation()), | |||
1126 | IsPromiseDependentType( | |||
1127 | !Fn.CoroutinePromise || | |||
1128 | Fn.CoroutinePromise->getType()->isDependentType()) { | |||
1129 | this->Body = Body; | |||
1130 | ||||
1131 | for (auto KV : Fn.CoroutineParameterMoves) | |||
1132 | this->ParamMovesVector.push_back(KV.second); | |||
1133 | this->ParamMoves = this->ParamMovesVector; | |||
1134 | ||||
1135 | if (!IsPromiseDependentType) { | |||
1136 | PromiseRecordDecl = Fn.CoroutinePromise->getType()->getAsCXXRecordDecl(); | |||
1137 | assert(PromiseRecordDecl && "Type should have already been checked")((PromiseRecordDecl && "Type should have already been checked" ) ? static_cast<void> (0) : __assert_fail ("PromiseRecordDecl && \"Type should have already been checked\"" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaCoroutine.cpp" , 1137, __PRETTY_FUNCTION__)); | |||
1138 | } | |||
1139 | this->IsValid = makePromiseStmt() && makeInitialAndFinalSuspend(); | |||
1140 | } | |||
1141 | ||||
1142 | bool CoroutineStmtBuilder::buildStatements() { | |||
1143 | assert(this->IsValid && "coroutine already invalid")((this->IsValid && "coroutine already invalid") ? static_cast <void> (0) : __assert_fail ("this->IsValid && \"coroutine already invalid\"" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaCoroutine.cpp" , 1143, __PRETTY_FUNCTION__)); | |||
1144 | this->IsValid = makeReturnObject(); | |||
1145 | if (this->IsValid && !IsPromiseDependentType) | |||
1146 | buildDependentStatements(); | |||
1147 | return this->IsValid; | |||
1148 | } | |||
1149 | ||||
1150 | bool CoroutineStmtBuilder::buildDependentStatements() { | |||
1151 | assert(this->IsValid && "coroutine already invalid")((this->IsValid && "coroutine already invalid") ? static_cast <void> (0) : __assert_fail ("this->IsValid && \"coroutine already invalid\"" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaCoroutine.cpp" , 1151, __PRETTY_FUNCTION__)); | |||
1152 | assert(!this->IsPromiseDependentType &&((!this->IsPromiseDependentType && "coroutine cannot have a dependent promise type" ) ? static_cast<void> (0) : __assert_fail ("!this->IsPromiseDependentType && \"coroutine cannot have a dependent promise type\"" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaCoroutine.cpp" , 1153, __PRETTY_FUNCTION__)) | |||
1153 | "coroutine cannot have a dependent promise type")((!this->IsPromiseDependentType && "coroutine cannot have a dependent promise type" ) ? static_cast<void> (0) : __assert_fail ("!this->IsPromiseDependentType && \"coroutine cannot have a dependent promise type\"" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaCoroutine.cpp" , 1153, __PRETTY_FUNCTION__)); | |||
1154 | this->IsValid = makeOnException() && makeOnFallthrough() && | |||
1155 | makeGroDeclAndReturnStmt() && makeReturnOnAllocFailure() && | |||
1156 | makeNewAndDeleteExpr(); | |||
1157 | return this->IsValid; | |||
1158 | } | |||
1159 | ||||
1160 | bool CoroutineStmtBuilder::makePromiseStmt() { | |||
1161 | // Form a declaration statement for the promise declaration, so that AST | |||
1162 | // visitors can more easily find it. | |||
1163 | StmtResult PromiseStmt = | |||
1164 | S.ActOnDeclStmt(S.ConvertDeclToDeclGroup(Fn.CoroutinePromise), Loc, Loc); | |||
1165 | if (PromiseStmt.isInvalid()) | |||
1166 | return false; | |||
1167 | ||||
1168 | this->Promise = PromiseStmt.get(); | |||
1169 | return true; | |||
1170 | } | |||
1171 | ||||
1172 | bool CoroutineStmtBuilder::makeInitialAndFinalSuspend() { | |||
1173 | if (Fn.hasInvalidCoroutineSuspends()) | |||
1174 | return false; | |||
1175 | this->InitialSuspend = cast<Expr>(Fn.CoroutineSuspends.first); | |||
1176 | this->FinalSuspend = cast<Expr>(Fn.CoroutineSuspends.second); | |||
1177 | return true; | |||
1178 | } | |||
1179 | ||||
1180 | static bool diagReturnOnAllocFailure(Sema &S, Expr *E, | |||
1181 | CXXRecordDecl *PromiseRecordDecl, | |||
1182 | FunctionScopeInfo &Fn) { | |||
1183 | auto Loc = E->getExprLoc(); | |||
1184 | if (auto *DeclRef = dyn_cast_or_null<DeclRefExpr>(E)) { | |||
1185 | auto *Decl = DeclRef->getDecl(); | |||
1186 | if (CXXMethodDecl *Method = dyn_cast_or_null<CXXMethodDecl>(Decl)) { | |||
1187 | if (Method->isStatic()) | |||
1188 | return true; | |||
1189 | else | |||
1190 | Loc = Decl->getLocation(); | |||
1191 | } | |||
1192 | } | |||
1193 | ||||
1194 | S.Diag( | |||
1195 | Loc, | |||
1196 | diag::err_coroutine_promise_get_return_object_on_allocation_failure) | |||
1197 | << PromiseRecordDecl; | |||
1198 | S.Diag(Fn.FirstCoroutineStmtLoc, diag::note_declared_coroutine_here) | |||
1199 | << Fn.getFirstCoroutineStmtKeyword(); | |||
1200 | return false; | |||
1201 | } | |||
1202 | ||||
1203 | bool CoroutineStmtBuilder::makeReturnOnAllocFailure() { | |||
1204 | assert(!IsPromiseDependentType &&((!IsPromiseDependentType && "cannot make statement while the promise type is dependent" ) ? static_cast<void> (0) : __assert_fail ("!IsPromiseDependentType && \"cannot make statement while the promise type is dependent\"" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaCoroutine.cpp" , 1205, __PRETTY_FUNCTION__)) | |||
1205 | "cannot make statement while the promise type is dependent")((!IsPromiseDependentType && "cannot make statement while the promise type is dependent" ) ? static_cast<void> (0) : __assert_fail ("!IsPromiseDependentType && \"cannot make statement while the promise type is dependent\"" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaCoroutine.cpp" , 1205, __PRETTY_FUNCTION__)); | |||
1206 | ||||
1207 | // [dcl.fct.def.coroutine]/8 | |||
1208 | // The unqualified-id get_return_object_on_allocation_failure is looked up in | |||
1209 | // the scope of class P by class member access lookup (3.4.5). ... | |||
1210 | // If an allocation function returns nullptr, ... the coroutine return value | |||
1211 | // is obtained by a call to ... get_return_object_on_allocation_failure(). | |||
1212 | ||||
1213 | DeclarationName DN = | |||
1214 | S.PP.getIdentifierInfo("get_return_object_on_allocation_failure"); | |||
1215 | LookupResult Found(S, DN, Loc, Sema::LookupMemberName); | |||
1216 | if (!S.LookupQualifiedName(Found, PromiseRecordDecl)) | |||
1217 | return true; | |||
1218 | ||||
1219 | CXXScopeSpec SS; | |||
1220 | ExprResult DeclNameExpr = | |||
1221 | S.BuildDeclarationNameExpr(SS, Found, /*NeedsADL=*/false); | |||
1222 | if (DeclNameExpr.isInvalid()) | |||
1223 | return false; | |||
1224 | ||||
1225 | if (!diagReturnOnAllocFailure(S, DeclNameExpr.get(), PromiseRecordDecl, Fn)) | |||
1226 | return false; | |||
1227 | ||||
1228 | ExprResult ReturnObjectOnAllocationFailure = | |||
1229 | S.BuildCallExpr(nullptr, DeclNameExpr.get(), Loc, {}, Loc); | |||
1230 | if (ReturnObjectOnAllocationFailure.isInvalid()) | |||
1231 | return false; | |||
1232 | ||||
1233 | StmtResult ReturnStmt = | |||
1234 | S.BuildReturnStmt(Loc, ReturnObjectOnAllocationFailure.get()); | |||
1235 | if (ReturnStmt.isInvalid()) { | |||
1236 | S.Diag(Found.getFoundDecl()->getLocation(), diag::note_member_declared_here) | |||
1237 | << DN; | |||
1238 | S.Diag(Fn.FirstCoroutineStmtLoc, diag::note_declared_coroutine_here) | |||
1239 | << Fn.getFirstCoroutineStmtKeyword(); | |||
1240 | return false; | |||
1241 | } | |||
1242 | ||||
1243 | this->ReturnStmtOnAllocFailure = ReturnStmt.get(); | |||
1244 | return true; | |||
1245 | } | |||
1246 | ||||
1247 | bool CoroutineStmtBuilder::makeNewAndDeleteExpr() { | |||
1248 | // Form and check allocation and deallocation calls. | |||
1249 | assert(!IsPromiseDependentType &&((!IsPromiseDependentType && "cannot make statement while the promise type is dependent" ) ? static_cast<void> (0) : __assert_fail ("!IsPromiseDependentType && \"cannot make statement while the promise type is dependent\"" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaCoroutine.cpp" , 1250, __PRETTY_FUNCTION__)) | |||
1250 | "cannot make statement while the promise type is dependent")((!IsPromiseDependentType && "cannot make statement while the promise type is dependent" ) ? static_cast<void> (0) : __assert_fail ("!IsPromiseDependentType && \"cannot make statement while the promise type is dependent\"" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaCoroutine.cpp" , 1250, __PRETTY_FUNCTION__)); | |||
1251 | QualType PromiseType = Fn.CoroutinePromise->getType(); | |||
1252 | ||||
1253 | if (S.RequireCompleteType(Loc, PromiseType, diag::err_incomplete_type)) | |||
1254 | return false; | |||
1255 | ||||
1256 | const bool RequiresNoThrowAlloc = ReturnStmtOnAllocFailure != nullptr; | |||
1257 | ||||
1258 | // [dcl.fct.def.coroutine]/7 | |||
1259 | // Lookup allocation functions using a parameter list composed of the | |||
1260 | // requested size of the coroutine state being allocated, followed by | |||
1261 | // the coroutine function's arguments. If a matching allocation function | |||
1262 | // exists, use it. Otherwise, use an allocation function that just takes | |||
1263 | // the requested size. | |||
1264 | ||||
1265 | FunctionDecl *OperatorNew = nullptr; | |||
1266 | FunctionDecl *OperatorDelete = nullptr; | |||
1267 | FunctionDecl *UnusedResult = nullptr; | |||
1268 | bool PassAlignment = false; | |||
1269 | SmallVector<Expr *, 1> PlacementArgs; | |||
1270 | ||||
1271 | // [dcl.fct.def.coroutine]/7 | |||
1272 | // "The allocation function’s name is looked up in the scope of P. | |||
1273 | // [...] If the lookup finds an allocation function in the scope of P, | |||
1274 | // overload resolution is performed on a function call created by assembling | |||
1275 | // an argument list. The first argument is the amount of space requested, | |||
1276 | // and has type std::size_t. The lvalues p1 ... pn are the succeeding | |||
1277 | // arguments." | |||
1278 | // | |||
1279 | // ...where "p1 ... pn" are defined earlier as: | |||
1280 | // | |||
1281 | // [dcl.fct.def.coroutine]/3 | |||
1282 | // "For a coroutine f that is a non-static member function, let P1 denote the | |||
1283 | // type of the implicit object parameter (13.3.1) and P2 ... Pn be the types | |||
1284 | // of the function parameters; otherwise let P1 ... Pn be the types of the | |||
1285 | // function parameters. Let p1 ... pn be lvalues denoting those objects." | |||
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]/7 | |||
1317 | // "If no matching function is found, overload resolution is performed again | |||
1318 | // on a function call created by passing just the amount of space required as | |||
1319 | // 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]/7 | |||
1329 | // "The allocation function’s name is looked up in the scope of P. If this | |||
1330 | // lookup fails, the allocation function’s name is looked up in the global | |||
1331 | // scope." | |||
1332 | if (!OperatorNew) { | |||
1333 | S.FindAllocationFunctions(Loc, SourceRange(), /*NewScope*/ Sema::AFS_Global, | |||
1334 | /*DeleteScope*/ Sema::AFS_Both, PromiseType, | |||
1335 | /*isArray*/ false, PassAlignment, PlacementArgs, | |||
1336 | OperatorNew, UnusedResult); | |||
1337 | } | |||
1338 | ||||
1339 | bool IsGlobalOverload = | |||
1340 | OperatorNew && !isa<CXXRecordDecl>(OperatorNew->getDeclContext()); | |||
1341 | // If we didn't find a class-local new declaration and non-throwing new | |||
1342 | // was is required then we need to lookup the non-throwing global operator | |||
1343 | // instead. | |||
1344 | if (RequiresNoThrowAlloc && (!OperatorNew || IsGlobalOverload)) { | |||
1345 | auto *StdNoThrow = buildStdNoThrowDeclRef(S, Loc); | |||
1346 | if (!StdNoThrow) | |||
1347 | return false; | |||
1348 | PlacementArgs = {StdNoThrow}; | |||
1349 | OperatorNew = nullptr; | |||
1350 | S.FindAllocationFunctions(Loc, SourceRange(), /*NewScope*/ Sema::AFS_Both, | |||
1351 | /*DeleteScope*/ Sema::AFS_Both, PromiseType, | |||
1352 | /*isArray*/ false, PassAlignment, PlacementArgs, | |||
1353 | OperatorNew, UnusedResult); | |||
1354 | } | |||
1355 | ||||
1356 | if (!OperatorNew) | |||
1357 | return false; | |||
1358 | ||||
1359 | if (RequiresNoThrowAlloc) { | |||
1360 | const auto *FT = OperatorNew->getType()->castAs<FunctionProtoType>(); | |||
1361 | if (!FT->isNothrow(/*ResultIfDependent*/ false)) { | |||
1362 | S.Diag(OperatorNew->getLocation(), | |||
1363 | diag::err_coroutine_promise_new_requires_nothrow) | |||
1364 | << OperatorNew; | |||
1365 | S.Diag(Loc, diag::note_coroutine_promise_call_implicitly_required) | |||
1366 | << OperatorNew; | |||
1367 | return false; | |||
1368 | } | |||
1369 | } | |||
1370 | ||||
1371 | if ((OperatorDelete = findDeleteForPromise(S, Loc, PromiseType)) == nullptr) | |||
1372 | return false; | |||
1373 | ||||
1374 | Expr *FramePtr = | |||
1375 | buildBuiltinCall(S, Loc, Builtin::BI__builtin_coro_frame, {}); | |||
1376 | ||||
1377 | Expr *FrameSize = | |||
1378 | buildBuiltinCall(S, Loc, Builtin::BI__builtin_coro_size, {}); | |||
1379 | ||||
1380 | // Make new call. | |||
1381 | ||||
1382 | ExprResult NewRef = | |||
1383 | S.BuildDeclRefExpr(OperatorNew, OperatorNew->getType(), VK_LValue, Loc); | |||
1384 | if (NewRef.isInvalid()) | |||
1385 | return false; | |||
1386 | ||||
1387 | SmallVector<Expr *, 2> NewArgs(1, FrameSize); | |||
1388 | for (auto Arg : PlacementArgs) | |||
1389 | NewArgs.push_back(Arg); | |||
1390 | ||||
1391 | ExprResult NewExpr = | |||
1392 | S.BuildCallExpr(S.getCurScope(), NewRef.get(), Loc, NewArgs, Loc); | |||
1393 | NewExpr = S.ActOnFinishFullExpr(NewExpr.get(), /*DiscardedValue*/ false); | |||
1394 | if (NewExpr.isInvalid()) | |||
1395 | return false; | |||
1396 | ||||
1397 | // Make delete call. | |||
1398 | ||||
1399 | QualType OpDeleteQualType = OperatorDelete->getType(); | |||
1400 | ||||
1401 | ExprResult DeleteRef = | |||
1402 | S.BuildDeclRefExpr(OperatorDelete, OpDeleteQualType, VK_LValue, Loc); | |||
1403 | if (DeleteRef.isInvalid()) | |||
1404 | return false; | |||
1405 | ||||
1406 | Expr *CoroFree = | |||
1407 | buildBuiltinCall(S, Loc, Builtin::BI__builtin_coro_free, {FramePtr}); | |||
1408 | ||||
1409 | SmallVector<Expr *, 2> DeleteArgs{CoroFree}; | |||
1410 | ||||
1411 | // Check if we need to pass the size. | |||
1412 | const auto *OpDeleteType = | |||
1413 | OpDeleteQualType.getTypePtr()->castAs<FunctionProtoType>(); | |||
1414 | if (OpDeleteType->getNumParams() > 1) | |||
1415 | DeleteArgs.push_back(FrameSize); | |||
1416 | ||||
1417 | ExprResult DeleteExpr = | |||
1418 | S.BuildCallExpr(S.getCurScope(), DeleteRef.get(), Loc, DeleteArgs, Loc); | |||
1419 | DeleteExpr = | |||
1420 | S.ActOnFinishFullExpr(DeleteExpr.get(), /*DiscardedValue*/ false); | |||
1421 | if (DeleteExpr.isInvalid()) | |||
1422 | return false; | |||
1423 | ||||
1424 | this->Allocate = NewExpr.get(); | |||
1425 | this->Deallocate = DeleteExpr.get(); | |||
1426 | ||||
1427 | return true; | |||
1428 | } | |||
1429 | ||||
1430 | bool CoroutineStmtBuilder::makeOnFallthrough() { | |||
1431 | assert(!IsPromiseDependentType &&((!IsPromiseDependentType && "cannot make statement while the promise type is dependent" ) ? static_cast<void> (0) : __assert_fail ("!IsPromiseDependentType && \"cannot make statement while the promise type is dependent\"" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaCoroutine.cpp" , 1432, __PRETTY_FUNCTION__)) | |||
1432 | "cannot make statement while the promise type is dependent")((!IsPromiseDependentType && "cannot make statement while the promise type is dependent" ) ? static_cast<void> (0) : __assert_fail ("!IsPromiseDependentType && \"cannot make statement while the promise type is dependent\"" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaCoroutine.cpp" , 1432, __PRETTY_FUNCTION__)); | |||
1433 | ||||
1434 | // [dcl.fct.def.coroutine]/4 | |||
1435 | // The unqualified-ids 'return_void' and 'return_value' are looked up in | |||
1436 | // the scope of class P. If both are found, the program is ill-formed. | |||
1437 | bool HasRVoid, HasRValue; | |||
1438 | LookupResult LRVoid = | |||
1439 | lookupMember(S, "return_void", PromiseRecordDecl, Loc, HasRVoid); | |||
1440 | LookupResult LRValue = | |||
1441 | lookupMember(S, "return_value", PromiseRecordDecl, Loc, HasRValue); | |||
1442 | ||||
1443 | StmtResult Fallthrough; | |||
1444 | if (HasRVoid && HasRValue) { | |||
1445 | // FIXME Improve this diagnostic | |||
1446 | S.Diag(FD.getLocation(), | |||
1447 | diag::err_coroutine_promise_incompatible_return_functions) | |||
1448 | << PromiseRecordDecl; | |||
1449 | S.Diag(LRVoid.getRepresentativeDecl()->getLocation(), | |||
1450 | diag::note_member_first_declared_here) | |||
1451 | << LRVoid.getLookupName(); | |||
1452 | S.Diag(LRValue.getRepresentativeDecl()->getLocation(), | |||
1453 | diag::note_member_first_declared_here) | |||
1454 | << LRValue.getLookupName(); | |||
1455 | return false; | |||
1456 | } else if (!HasRVoid && !HasRValue) { | |||
1457 | // FIXME: The PDTS currently specifies this case as UB, not ill-formed. | |||
1458 | // However we still diagnose this as an error since until the PDTS is fixed. | |||
1459 | S.Diag(FD.getLocation(), | |||
1460 | diag::err_coroutine_promise_requires_return_function) | |||
1461 | << PromiseRecordDecl; | |||
1462 | S.Diag(PromiseRecordDecl->getLocation(), diag::note_defined_here) | |||
1463 | << PromiseRecordDecl; | |||
1464 | return false; | |||
1465 | } else if (HasRVoid) { | |||
1466 | // If the unqualified-id return_void is found, flowing off the end of a | |||
1467 | // coroutine is equivalent to a co_return with no operand. Otherwise, | |||
1468 | // flowing off the end of a coroutine results in undefined behavior. | |||
1469 | Fallthrough = S.BuildCoreturnStmt(FD.getLocation(), nullptr, | |||
1470 | /*IsImplicit*/false); | |||
1471 | Fallthrough = S.ActOnFinishFullStmt(Fallthrough.get()); | |||
1472 | if (Fallthrough.isInvalid()) | |||
1473 | return false; | |||
1474 | } | |||
1475 | ||||
1476 | this->OnFallthrough = Fallthrough.get(); | |||
1477 | return true; | |||
1478 | } | |||
1479 | ||||
1480 | bool CoroutineStmtBuilder::makeOnException() { | |||
1481 | // Try to form 'p.unhandled_exception();' | |||
1482 | assert(!IsPromiseDependentType &&((!IsPromiseDependentType && "cannot make statement while the promise type is dependent" ) ? static_cast<void> (0) : __assert_fail ("!IsPromiseDependentType && \"cannot make statement while the promise type is dependent\"" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaCoroutine.cpp" , 1483, __PRETTY_FUNCTION__)) | |||
1483 | "cannot make statement while the promise type is dependent")((!IsPromiseDependentType && "cannot make statement while the promise type is dependent" ) ? static_cast<void> (0) : __assert_fail ("!IsPromiseDependentType && \"cannot make statement while the promise type is dependent\"" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaCoroutine.cpp" , 1483, __PRETTY_FUNCTION__)); | |||
1484 | ||||
1485 | const bool RequireUnhandledException = S.getLangOpts().CXXExceptions; | |||
1486 | ||||
1487 | if (!lookupMember(S, "unhandled_exception", PromiseRecordDecl, Loc)) { | |||
1488 | auto DiagID = | |||
1489 | RequireUnhandledException | |||
1490 | ? diag::err_coroutine_promise_unhandled_exception_required | |||
1491 | : diag:: | |||
1492 | warn_coroutine_promise_unhandled_exception_required_with_exceptions; | |||
1493 | S.Diag(Loc, DiagID) << PromiseRecordDecl; | |||
1494 | S.Diag(PromiseRecordDecl->getLocation(), diag::note_defined_here) | |||
1495 | << PromiseRecordDecl; | |||
1496 | return !RequireUnhandledException; | |||
1497 | } | |||
1498 | ||||
1499 | // If exceptions are disabled, don't try to build OnException. | |||
1500 | if (!S.getLangOpts().CXXExceptions) | |||
1501 | return true; | |||
1502 | ||||
1503 | ExprResult UnhandledException = buildPromiseCall(S, Fn.CoroutinePromise, Loc, | |||
1504 | "unhandled_exception", None); | |||
1505 | UnhandledException = S.ActOnFinishFullExpr(UnhandledException.get(), Loc, | |||
1506 | /*DiscardedValue*/ false); | |||
1507 | if (UnhandledException.isInvalid()) | |||
1508 | return false; | |||
1509 | ||||
1510 | // Since the body of the coroutine will be wrapped in try-catch, it will | |||
1511 | // be incompatible with SEH __try if present in a function. | |||
1512 | if (!S.getLangOpts().Borland && Fn.FirstSEHTryLoc.isValid()) { | |||
1513 | S.Diag(Fn.FirstSEHTryLoc, diag::err_seh_in_a_coroutine_with_cxx_exceptions); | |||
1514 | S.Diag(Fn.FirstCoroutineStmtLoc, diag::note_declared_coroutine_here) | |||
1515 | << Fn.getFirstCoroutineStmtKeyword(); | |||
1516 | return false; | |||
1517 | } | |||
1518 | ||||
1519 | this->OnException = UnhandledException.get(); | |||
1520 | return true; | |||
1521 | } | |||
1522 | ||||
1523 | bool CoroutineStmtBuilder::makeReturnObject() { | |||
1524 | // Build implicit 'p.get_return_object()' expression and form initialization | |||
1525 | // of return type from it. | |||
1526 | ExprResult ReturnObject = | |||
1527 | buildPromiseCall(S, Fn.CoroutinePromise, Loc, "get_return_object", None); | |||
1528 | if (ReturnObject.isInvalid()) | |||
1529 | return false; | |||
1530 | ||||
1531 | this->ReturnValue = ReturnObject.get(); | |||
1532 | return true; | |||
1533 | } | |||
1534 | ||||
1535 | static void noteMemberDeclaredHere(Sema &S, Expr *E, FunctionScopeInfo &Fn) { | |||
1536 | if (auto *MbrRef = dyn_cast<CXXMemberCallExpr>(E)) { | |||
1537 | auto *MethodDecl = MbrRef->getMethodDecl(); | |||
1538 | S.Diag(MethodDecl->getLocation(), diag::note_member_declared_here) | |||
1539 | << MethodDecl; | |||
1540 | } | |||
1541 | S.Diag(Fn.FirstCoroutineStmtLoc, diag::note_declared_coroutine_here) | |||
1542 | << Fn.getFirstCoroutineStmtKeyword(); | |||
1543 | } | |||
1544 | ||||
1545 | bool CoroutineStmtBuilder::makeGroDeclAndReturnStmt() { | |||
1546 | assert(!IsPromiseDependentType &&((!IsPromiseDependentType && "cannot make statement while the promise type is dependent" ) ? static_cast<void> (0) : __assert_fail ("!IsPromiseDependentType && \"cannot make statement while the promise type is dependent\"" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaCoroutine.cpp" , 1547, __PRETTY_FUNCTION__)) | |||
1547 | "cannot make statement while the promise type is dependent")((!IsPromiseDependentType && "cannot make statement while the promise type is dependent" ) ? static_cast<void> (0) : __assert_fail ("!IsPromiseDependentType && \"cannot make statement while the promise type is dependent\"" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaCoroutine.cpp" , 1547, __PRETTY_FUNCTION__)); | |||
1548 | assert(this->ReturnValue && "ReturnValue must be already formed")((this->ReturnValue && "ReturnValue must be already formed" ) ? static_cast<void> (0) : __assert_fail ("this->ReturnValue && \"ReturnValue must be already formed\"" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaCoroutine.cpp" , 1548, __PRETTY_FUNCTION__)); | |||
1549 | ||||
1550 | QualType const GroType = this->ReturnValue->getType(); | |||
1551 | assert(!GroType->isDependentType() &&((!GroType->isDependentType() && "get_return_object type must no longer be dependent" ) ? static_cast<void> (0) : __assert_fail ("!GroType->isDependentType() && \"get_return_object type must no longer be dependent\"" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaCoroutine.cpp" , 1552, __PRETTY_FUNCTION__)) | |||
1552 | "get_return_object type must no longer be dependent")((!GroType->isDependentType() && "get_return_object type must no longer be dependent" ) ? static_cast<void> (0) : __assert_fail ("!GroType->isDependentType() && \"get_return_object type must no longer be dependent\"" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaCoroutine.cpp" , 1552, __PRETTY_FUNCTION__)); | |||
1553 | ||||
1554 | QualType const FnRetType = FD.getReturnType(); | |||
1555 | assert(!FnRetType->isDependentType() &&((!FnRetType->isDependentType() && "get_return_object type must no longer be dependent" ) ? static_cast<void> (0) : __assert_fail ("!FnRetType->isDependentType() && \"get_return_object type must no longer be dependent\"" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaCoroutine.cpp" , 1556, __PRETTY_FUNCTION__)) | |||
1556 | "get_return_object type must no longer be dependent")((!FnRetType->isDependentType() && "get_return_object type must no longer be dependent" ) ? static_cast<void> (0) : __assert_fail ("!FnRetType->isDependentType() && \"get_return_object type must no longer be dependent\"" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaCoroutine.cpp" , 1556, __PRETTY_FUNCTION__)); | |||
1557 | ||||
1558 | if (FnRetType->isVoidType()) { | |||
1559 | ExprResult Res = | |||
1560 | S.ActOnFinishFullExpr(this->ReturnValue, Loc, /*DiscardedValue*/ false); | |||
1561 | if (Res.isInvalid()) | |||
1562 | return false; | |||
1563 | ||||
1564 | this->ResultDecl = Res.get(); | |||
1565 | return true; | |||
1566 | } | |||
1567 | ||||
1568 | if (GroType->isVoidType()) { | |||
1569 | // Trigger a nice error message. | |||
1570 | InitializedEntity Entity = | |||
1571 | InitializedEntity::InitializeResult(Loc, FnRetType, false); | |||
1572 | S.PerformMoveOrCopyInitialization(Entity, nullptr, FnRetType, ReturnValue); | |||
1573 | noteMemberDeclaredHere(S, ReturnValue, Fn); | |||
1574 | return false; | |||
1575 | } | |||
1576 | ||||
1577 | auto *GroDecl = VarDecl::Create( | |||
1578 | S.Context, &FD, FD.getLocation(), FD.getLocation(), | |||
1579 | &S.PP.getIdentifierTable().get("__coro_gro"), GroType, | |||
1580 | S.Context.getTrivialTypeSourceInfo(GroType, Loc), SC_None); | |||
1581 | GroDecl->setImplicit(); | |||
1582 | ||||
1583 | S.CheckVariableDeclarationType(GroDecl); | |||
1584 | if (GroDecl->isInvalidDecl()) | |||
1585 | return false; | |||
1586 | ||||
1587 | InitializedEntity Entity = InitializedEntity::InitializeVariable(GroDecl); | |||
1588 | ExprResult Res = S.PerformMoveOrCopyInitialization(Entity, nullptr, GroType, | |||
1589 | this->ReturnValue); | |||
1590 | if (Res.isInvalid()) | |||
1591 | return false; | |||
1592 | ||||
1593 | Res = S.ActOnFinishFullExpr(Res.get(), /*DiscardedValue*/ false); | |||
1594 | if (Res.isInvalid()) | |||
1595 | return false; | |||
1596 | ||||
1597 | S.AddInitializerToDecl(GroDecl, Res.get(), | |||
1598 | /*DirectInit=*/false); | |||
1599 | ||||
1600 | S.FinalizeDeclaration(GroDecl); | |||
1601 | ||||
1602 | // Form a declaration statement for the return declaration, so that AST | |||
1603 | // visitors can more easily find it. | |||
1604 | StmtResult GroDeclStmt = | |||
1605 | S.ActOnDeclStmt(S.ConvertDeclToDeclGroup(GroDecl), Loc, Loc); | |||
1606 | if (GroDeclStmt.isInvalid()) | |||
1607 | return false; | |||
1608 | ||||
1609 | this->ResultDecl = GroDeclStmt.get(); | |||
1610 | ||||
1611 | ExprResult declRef = S.BuildDeclRefExpr(GroDecl, GroType, VK_LValue, Loc); | |||
1612 | if (declRef.isInvalid()) | |||
1613 | return false; | |||
1614 | ||||
1615 | StmtResult ReturnStmt = S.BuildReturnStmt(Loc, declRef.get()); | |||
1616 | if (ReturnStmt.isInvalid()) { | |||
1617 | noteMemberDeclaredHere(S, ReturnValue, Fn); | |||
1618 | return false; | |||
1619 | } | |||
1620 | if (cast<clang::ReturnStmt>(ReturnStmt.get())->getNRVOCandidate() == GroDecl) | |||
1621 | GroDecl->setNRVOVariable(true); | |||
1622 | ||||
1623 | this->ReturnStmt = ReturnStmt.get(); | |||
1624 | return true; | |||
1625 | } | |||
1626 | ||||
1627 | // Create a static_cast\<T&&>(expr). | |||
1628 | static Expr *castForMoving(Sema &S, Expr *E, QualType T = QualType()) { | |||
1629 | if (T.isNull()) | |||
1630 | T = E->getType(); | |||
1631 | QualType TargetType = S.BuildReferenceType( | |||
1632 | T, /*SpelledAsLValue*/ false, SourceLocation(), DeclarationName()); | |||
1633 | SourceLocation ExprLoc = E->getBeginLoc(); | |||
1634 | TypeSourceInfo *TargetLoc = | |||
1635 | S.Context.getTrivialTypeSourceInfo(TargetType, ExprLoc); | |||
1636 | ||||
1637 | return S | |||
1638 | .BuildCXXNamedCast(ExprLoc, tok::kw_static_cast, TargetLoc, E, | |||
1639 | SourceRange(ExprLoc, ExprLoc), E->getSourceRange()) | |||
1640 | .get(); | |||
1641 | } | |||
1642 | ||||
1643 | /// Build a variable declaration for move parameter. | |||
1644 | static VarDecl *buildVarDecl(Sema &S, SourceLocation Loc, QualType Type, | |||
1645 | IdentifierInfo *II) { | |||
1646 | TypeSourceInfo *TInfo = S.Context.getTrivialTypeSourceInfo(Type, Loc); | |||
1647 | VarDecl *Decl = VarDecl::Create(S.Context, S.CurContext, Loc, Loc, II, Type, | |||
1648 | TInfo, SC_None); | |||
1649 | Decl->setImplicit(); | |||
1650 | return Decl; | |||
1651 | } | |||
1652 | ||||
1653 | // Build statements that move coroutine function parameters to the coroutine | |||
1654 | // frame, and store them on the function scope info. | |||
1655 | bool Sema::buildCoroutineParameterMoves(SourceLocation Loc) { | |||
1656 | assert(isa<FunctionDecl>(CurContext) && "not in a function scope")((isa<FunctionDecl>(CurContext) && "not in a function scope" ) ? static_cast<void> (0) : __assert_fail ("isa<FunctionDecl>(CurContext) && \"not in a function scope\"" , "/build/llvm-toolchain-snapshot-12~++20210124100612+2afaf072f5c1/clang/lib/Sema/SemaCoroutine.cpp" , 1656, __PRETTY_FUNCTION__)); | |||
1657 | auto *FD = cast<FunctionDecl>(CurContext); | |||
1658 | ||||
1659 | auto *ScopeInfo = getCurFunction(); | |||
1660 | if (!ScopeInfo->CoroutineParameterMoves.empty()) | |||
1661 | return false; | |||
1662 | ||||
1663 | for (auto *PD : FD->parameters()) { | |||
1664 | if (PD->getType()->isDependentType()) | |||
1665 | continue; | |||
1666 | ||||
1667 | ExprResult PDRefExpr = | |||
1668 | BuildDeclRefExpr(PD, PD->getType().getNonReferenceType(), | |||
1669 | ExprValueKind::VK_LValue, Loc); // FIXME: scope? | |||
1670 | if (PDRefExpr.isInvalid()) | |||
1671 | return false; | |||
1672 | ||||
1673 | Expr *CExpr = nullptr; | |||
1674 | if (PD->getType()->getAsCXXRecordDecl() || | |||
1675 | PD->getType()->isRValueReferenceType()) | |||
1676 | CExpr = castForMoving(*this, PDRefExpr.get()); | |||
1677 | else | |||
1678 | CExpr = PDRefExpr.get(); | |||
1679 | ||||
1680 | auto D = buildVarDecl(*this, Loc, PD->getType(), PD->getIdentifier()); | |||
1681 | AddInitializerToDecl(D, CExpr, /*DirectInit=*/true); | |||
1682 | ||||
1683 | // Convert decl to a statement. | |||
1684 | StmtResult Stmt = ActOnDeclStmt(ConvertDeclToDeclGroup(D), Loc, Loc); | |||
1685 | if (Stmt.isInvalid()) | |||
1686 | return false; | |||
1687 | ||||
1688 | ScopeInfo->CoroutineParameterMoves.insert(std::make_pair(PD, Stmt.get())); | |||
1689 | } | |||
1690 | return true; | |||
1691 | } | |||
1692 | ||||
1693 | StmtResult Sema::BuildCoroutineBodyStmt(CoroutineBodyStmt::CtorArgs Args) { | |||
1694 | CoroutineBodyStmt *Res = CoroutineBodyStmt::Create(Context, Args); | |||
1695 | if (!Res) | |||
1696 | return StmtError(); | |||
1697 | return Res; | |||
1698 | } | |||
1699 | ||||
1700 | ClassTemplateDecl *Sema::lookupCoroutineTraits(SourceLocation KwLoc, | |||
1701 | SourceLocation FuncLoc) { | |||
1702 | if (!StdCoroutineTraitsCache) { | |||
1703 | if (auto StdExp = lookupStdExperimentalNamespace()) { | |||
1704 | LookupResult Result(*this, | |||
1705 | &PP.getIdentifierTable().get("coroutine_traits"), | |||
1706 | FuncLoc, LookupOrdinaryName); | |||
1707 | if (!LookupQualifiedName(Result, StdExp)) { | |||
1708 | Diag(KwLoc, diag::err_implied_coroutine_type_not_found) | |||
1709 | << "std::experimental::coroutine_traits"; | |||
1710 | return nullptr; | |||
1711 | } | |||
1712 | if (!(StdCoroutineTraitsCache = | |||
1713 | Result.getAsSingle<ClassTemplateDecl>())) { | |||
1714 | Result.suppressDiagnostics(); | |||
1715 | NamedDecl *Found = *Result.begin(); | |||
1716 | Diag(Found->getLocation(), diag::err_malformed_std_coroutine_traits); | |||
1717 | return nullptr; | |||
1718 | } | |||
1719 | } | |||
1720 | } | |||
1721 | return StdCoroutineTraitsCache; | |||
1722 | } |