Author: ericwf Date: Thu Jun 15 14:43:36 2017 New Revision: 305496 URL: http://llvm.org/viewvc/llvm-project?rev=305496&view=rev Log: [coroutines] Allow co_await and co_yield expressions that return an lvalue to compile
Summary: The title says it all. Reviewers: GorNishanov, rsmith Reviewed By: GorNishanov Subscribers: rjmccall, cfe-commits Differential Revision: https://reviews.llvm.org/D34194 Modified: cfe/trunk/lib/AST/ExprClassification.cpp cfe/trunk/lib/CodeGen/CGCoroutine.cpp cfe/trunk/lib/CodeGen/CGExpr.cpp cfe/trunk/lib/CodeGen/CodeGenFunction.h cfe/trunk/test/CodeGenCoroutines/coro-await.cpp Modified: cfe/trunk/lib/AST/ExprClassification.cpp URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/AST/ExprClassification.cpp?rev=305496&r1=305495&r2=305496&view=diff ============================================================================== --- cfe/trunk/lib/AST/ExprClassification.cpp (original) +++ cfe/trunk/lib/AST/ExprClassification.cpp Thu Jun 15 14:43:36 2017 @@ -190,7 +190,6 @@ static Cl::Kinds ClassifyInternal(ASTCon case Expr::ArrayInitIndexExprClass: case Expr::NoInitExprClass: case Expr::DesignatedInitUpdateExprClass: - case Expr::CoyieldExprClass: return Cl::CL_PRValue; // Next come the complicated cases. @@ -414,7 +413,8 @@ static Cl::Kinds ClassifyInternal(ASTCon return ClassifyInternal(Ctx, cast<InitListExpr>(E)->getInit(0)); case Expr::CoawaitExprClass: - return ClassifyInternal(Ctx, cast<CoawaitExpr>(E)->getResumeExpr()); + case Expr::CoyieldExprClass: + return ClassifyInternal(Ctx, cast<CoroutineSuspendExpr>(E)->getResumeExpr()); } llvm_unreachable("unhandled expression kind in classification"); Modified: cfe/trunk/lib/CodeGen/CGCoroutine.cpp URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGCoroutine.cpp?rev=305496&r1=305495&r2=305496&view=diff ============================================================================== --- cfe/trunk/lib/CodeGen/CGCoroutine.cpp (original) +++ cfe/trunk/lib/CodeGen/CGCoroutine.cpp Thu Jun 15 14:43:36 2017 @@ -148,10 +148,16 @@ static SmallString<32> buildSuspendPrefi // // See llvm's docs/Coroutines.rst for more details. // -static RValue emitSuspendExpression(CodeGenFunction &CGF, CGCoroData &Coro, +namespace { + struct LValueOrRValue { + LValue LV; + RValue RV; + }; +} +static LValueOrRValue emitSuspendExpression(CodeGenFunction &CGF, CGCoroData &Coro, CoroutineSuspendExpr const &S, AwaitKind Kind, AggValueSlot aggSlot, - bool ignoreResult) { + bool ignoreResult, bool forLValue) { auto *E = S.getCommonExpr(); // FIXME: rsmith 5/22/2017. Does it still make sense for us to have a @@ -217,7 +223,12 @@ static RValue emitSuspendExpression(Code // Emit await_resume expression. CGF.EmitBlock(ReadyBlock); - return CGF.EmitAnyExpr(S.getResumeExpr(), aggSlot, ignoreResult); + LValueOrRValue Res; + if (forLValue) + Res.LV = CGF.EmitLValue(S.getResumeExpr()); + else + Res.RV = CGF.EmitAnyExpr(S.getResumeExpr(), aggSlot, ignoreResult); + return Res; } RValue CodeGenFunction::EmitCoawaitExpr(const CoawaitExpr &E, @@ -225,13 +236,13 @@ RValue CodeGenFunction::EmitCoawaitExpr( bool ignoreResult) { return emitSuspendExpression(*this, *CurCoro.Data, E, CurCoro.Data->CurrentAwaitKind, aggSlot, - ignoreResult); + ignoreResult, /*forLValue*/false).RV; } RValue CodeGenFunction::EmitCoyieldExpr(const CoyieldExpr &E, AggValueSlot aggSlot, bool ignoreResult) { return emitSuspendExpression(*this, *CurCoro.Data, E, AwaitKind::Yield, - aggSlot, ignoreResult); + aggSlot, ignoreResult, /*forLValue*/false).RV; } void CodeGenFunction::EmitCoreturnStmt(CoreturnStmt const &S) { @@ -240,6 +251,38 @@ void CodeGenFunction::EmitCoreturnStmt(C EmitBranchThroughCleanup(CurCoro.Data->FinalJD); } + +#ifndef NDEBUG +static QualType getCoroutineSuspendExprReturnType(const ASTContext &Ctx, + const CoroutineSuspendExpr *E) { + const auto *RE = E->getResumeExpr(); + // Is it possible for RE to be a CXXBindTemporaryExpr wrapping + // a MemberCallExpr? + assert(isa<CallExpr>(RE) && "unexpected suspend expression type"); + return cast<CallExpr>(RE)->getCallReturnType(Ctx); +} +#endif + +LValue +CodeGenFunction::EmitCoawaitLValue(const CoawaitExpr *E) { + assert(getCoroutineSuspendExprReturnType(getContext(), E)->isReferenceType() && + "Can't have a scalar return unless the return type is a " + "reference type!"); + return emitSuspendExpression(*this, *CurCoro.Data, *E, + CurCoro.Data->CurrentAwaitKind, AggValueSlot::ignored(), + /*ignoreResult*/false, /*forLValue*/true).LV; +} + +LValue +CodeGenFunction::EmitCoyieldLValue(const CoyieldExpr *E) { + assert(getCoroutineSuspendExprReturnType(getContext(), E)->isReferenceType() && + "Can't have a scalar return unless the return type is a " + "reference type!"); + return emitSuspendExpression(*this, *CurCoro.Data, *E, + AwaitKind::Yield, AggValueSlot::ignored(), + /*ignoreResult*/false, /*forLValue*/true).LV; +} + // Hunts for the parameter reference in the parameter copy/move declaration. namespace { struct GetParamRef : public StmtVisitor<GetParamRef> { Modified: cfe/trunk/lib/CodeGen/CGExpr.cpp URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGExpr.cpp?rev=305496&r1=305495&r2=305496&view=diff ============================================================================== --- cfe/trunk/lib/CodeGen/CGExpr.cpp (original) +++ cfe/trunk/lib/CodeGen/CGExpr.cpp Thu Jun 15 14:43:36 2017 @@ -1158,6 +1158,11 @@ LValue CodeGenFunction::EmitLValue(const case Expr::MaterializeTemporaryExprClass: return EmitMaterializeTemporaryExpr(cast<MaterializeTemporaryExpr>(E)); + + case Expr::CoawaitExprClass: + return EmitCoawaitLValue(cast<CoawaitExpr>(E)); + case Expr::CoyieldExprClass: + return EmitCoyieldLValue(cast<CoyieldExpr>(E)); } } Modified: cfe/trunk/lib/CodeGen/CodeGenFunction.h URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CodeGenFunction.h?rev=305496&r1=305495&r2=305496&view=diff ============================================================================== --- cfe/trunk/lib/CodeGen/CodeGenFunction.h (original) +++ cfe/trunk/lib/CodeGen/CodeGenFunction.h Thu Jun 15 14:43:36 2017 @@ -2550,9 +2550,11 @@ public: RValue EmitCoawaitExpr(const CoawaitExpr &E, AggValueSlot aggSlot = AggValueSlot::ignored(), bool ignoreResult = false); + LValue EmitCoawaitLValue(const CoawaitExpr *E); RValue EmitCoyieldExpr(const CoyieldExpr &E, AggValueSlot aggSlot = AggValueSlot::ignored(), bool ignoreResult = false); + LValue EmitCoyieldLValue(const CoyieldExpr *E); RValue EmitCoroutineIntrinsic(const CallExpr *E, unsigned int IID); void EnterCXXTryStmt(const CXXTryStmt &S, bool IsFnTryBlock = false); Modified: cfe/trunk/test/CodeGenCoroutines/coro-await.cpp URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGenCoroutines/coro-await.cpp?rev=305496&r1=305495&r2=305496&view=diff ============================================================================== --- cfe/trunk/test/CodeGenCoroutines/coro-await.cpp (original) +++ cfe/trunk/test/CodeGenCoroutines/coro-await.cpp Thu Jun 15 14:43:36 2017 @@ -1,4 +1,5 @@ -// RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -fcoroutines-ts -std=c++14 -emit-llvm %s -o - -disable-llvm-passes | FileCheck %s +// RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -fcoroutines-ts -std=c++14 \ +// RUN: -emit-llvm %s -o - -disable-llvm-passes -Wno-coroutine -Wno-unused | FileCheck %s namespace std { namespace experimental { @@ -278,3 +279,50 @@ void AwaitLValue() { suspend_always lval; co_await lval; } + +struct RefTag { }; + +struct AwaitResumeReturnsLValue { + bool await_ready(); + void await_suspend(std::experimental::coroutine_handle<>); + RefTag& await_resume(); +}; + + +template<> +struct std::experimental::coroutine_traits<void,double> { + struct promise_type { + void get_return_object(); + init_susp initial_suspend(); + final_susp final_suspend(); + void return_void(); + AwaitResumeReturnsLValue yield_value(int); + }; +}; + +// Verifies that we don't crash when returning an lvalue from an await_resume() +// expression. +// CHECK-LABEL: define void @_Z18AwaitReturnsLValued(double) +void AwaitReturnsLValue(double) { + AwaitResumeReturnsLValue a; + // CHECK: %[[AVAR:.+]] = alloca %struct.AwaitResumeReturnsLValue, + // CHECK: %[[XVAR:.+]] = alloca %struct.RefTag*, + + // CHECK: %[[YVAR:.+]] = alloca %struct.RefTag*, + // CHECK-NEXT: %[[TMP1:.+]] = alloca %struct.AwaitResumeReturnsLValue, + + // CHECK: %[[ZVAR:.+]] = alloca %struct.RefTag*, + // CHECK-NEXT: %[[TMP2:.+]] = alloca %struct.AwaitResumeReturnsLValue, + + // CHECK: %[[RES1:.+]] = call dereferenceable({{.*}}) %struct.RefTag* @_ZN24AwaitResumeReturnsLValue12await_resumeEv(%struct.AwaitResumeReturnsLValue* %[[AVAR]]) + // CHECK-NEXT: store %struct.RefTag* %[[RES1]], %struct.RefTag** %[[XVAR]], + RefTag& x = co_await a; + + // CHECK: %[[RES2:.+]] = call dereferenceable({{.*}}) %struct.RefTag* @_ZN24AwaitResumeReturnsLValue12await_resumeEv(%struct.AwaitResumeReturnsLValue* %[[TMP1]]) + // CHECK-NEXT: store %struct.RefTag* %[[RES2]], %struct.RefTag** %[[YVAR]], + + RefTag& y = co_await AwaitResumeReturnsLValue{}; + // CHECK: %[[RES3:.+]] = call dereferenceable({{.*}}) %struct.RefTag* @_ZN24AwaitResumeReturnsLValue12await_resumeEv(%struct.AwaitResumeReturnsLValue* %[[TMP2]]) + // CHECK-NEXT: store %struct.RefTag* %[[RES3]], %struct.RefTag** %[[ZVAR]], + RefTag& z = co_yield 42; +} _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
