From 663218b576d8d79dea546c5726d7c90c216b1358 Mon Sep 17 00:00:00 2001 From: Douglas Gregor Date: Fri, 21 May 2010 17:55:12 +0000 Subject: [PATCH] When generating the call arguments in a thunk to call the thunkee, do not make copies non-POD arguments or arguments passed by reference: just copy the pointers directly. This eliminates another source of the dreaded memcpy-of-non-PODs. Fixes PR7188. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@104327 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/CodeGen/CGVTables.cpp | 12 +++++++--- test/CodeGenCXX/thunks.cpp | 45 ++++++++++++++++++++++++++++++++++++++ 2 files changed, 54 insertions(+), 3 deletions(-) diff --git a/lib/CodeGen/CGVTables.cpp b/lib/CodeGen/CGVTables.cpp index 3c9b45ba8c..b66b9f8493 100644 --- a/lib/CodeGen/CGVTables.cpp +++ b/lib/CodeGen/CGVTables.cpp @@ -2642,9 +2642,15 @@ void CodeGenFunction::GenerateThunk(llvm::Function *Fn, GlobalDecl GD, ParmVarDecl *Param = *I; QualType ArgType = Param->getType(); - // FIXME: Declaring a DeclRefExpr on the stack is kinda icky. - DeclRefExpr ArgExpr(Param, ArgType.getNonReferenceType(), SourceLocation()); - CallArgs.push_back(std::make_pair(EmitCallArg(&ArgExpr, ArgType), ArgType)); + // Load the argument corresponding to this parameter. + RValue Arg; + if (ArgType->isReferenceType() || + (hasAggregateLLVMType(ArgType) && !ArgType->isAnyComplexType())) + Arg = RValue::get(Builder.CreateLoad(LocalDeclMap[Param])); + else + Arg = RValue::get(EmitLoadOfScalar(LocalDeclMap[Param], false, ArgType)); + + CallArgs.push_back(std::make_pair(Arg, ArgType)); } // Get our callee. diff --git a/test/CodeGenCXX/thunks.cpp b/test/CodeGenCXX/thunks.cpp index 8144770763..b6e18e6e01 100644 --- a/test/CodeGenCXX/thunks.cpp +++ b/test/CodeGenCXX/thunks.cpp @@ -173,6 +173,51 @@ namespace Test6 { X Thunks::f() { return X(); } } +namespace Test7 { + // PR7188 + struct X { + X(); + X(const X&); + X &operator=(const X&); + ~X(); + }; + + struct Small { short s; }; + struct Large { + char array[1024]; + }; + + class A { + protected: + virtual void foo() = 0; + }; + + class B : public A { + protected: + virtual void bar() = 0; + }; + + class C : public A { + protected: + virtual void baz(X, X&, _Complex float, Small, Small&, Large) = 0; + }; + + class D : public B, + public C { + + void foo() {} + void bar() {} + void baz(X, X&, _Complex float, Small, Small&, Large); + }; + + void D::baz(X, X&, _Complex float, Small, Small&, Large) { } + + // CHECK: define void @_ZThn8_N5Test71D3bazENS_1XERS1_CfNS_5SmallERS4_NS_5LargeE( + // CHECK-NOT: memcpy + // CHECK: ret void + void testD() { D d; } +} + // This is from Test5: // CHECK: define linkonce_odr void @_ZTv0_n24_N5Test51B1fEv // CHECK: define internal void @_ZThn8_N12_GLOBAL__N_11C1fEv( -- 2.40.0