Revert r130717, which caused a regression (<rdar://problem/9402621>).

llvm-svn: 131057

clang/lib/CodeGen/CGCall.cpp

@@ -1166,15 +1166,6 @@ void CodeGenFunction::EmitCallArg(CallArgList &args, const Expr *E,
     return args.add(EmitReferenceBindingToExpr(E, /*InitializedDecl=*/0),
                     type);
 
-  if (hasAggregateLLVMType(type) && isa<ImplicitCastExpr>(E) &&
-      cast<CastExpr>(E)->getCastKind() == CK_LValueToRValue) {
-    LValue L = EmitLValue(cast<CastExpr>(E)->getSubExpr());
-    assert(L.isSimple());
-    args.add(RValue::getAggregate(L.getAddress(), L.isVolatileQualified()),
-             type, /*NeedsCopy*/true);
-    return;
-  }
-
   args.add(EmitAnyExprToTemp(E), type);
 }
 
@@ -1240,10 +1231,6 @@ RValue CodeGenFunction::EmitCall(const CGFunctionInfo &CallInfo,
                             Alignment, I->Ty);
         else
           StoreComplexToAddr(RV.getComplexVal(), Args.back(), false);
-      } else if (I->NeedsCopy && !ArgInfo.getIndirectByVal()) {
-        Args.push_back(CreateMemTemp(I->Ty));
-        EmitAggregateCopy(Args.back(), RV.getAggregateAddr(), I->Ty,
-                          RV.isVolatileQualified());
       } else {
         Args.push_back(RV.getAggregateAddr());
       }

clang/lib/CodeGen/CGCall.h

@@ -47,9 +47,8 @@ namespace CodeGen {
   struct CallArg {
     RValue RV;
     QualType Ty;
-    bool NeedsCopy;
-    CallArg(RValue rv, QualType ty, bool needscopy)
-    : RV(rv), Ty(ty), NeedsCopy(needscopy)
+    CallArg(RValue rv, QualType ty)
+    : RV(rv), Ty(ty)
     { }
   };
 
@@ -58,8 +57,8 @@ namespace CodeGen {
   class CallArgList :
     public llvm::SmallVector<CallArg, 16> {
   public:
-    void add(RValue rvalue, QualType type, bool needscopy = false) {
-      push_back(CallArg(rvalue, type, needscopy));
+    void add(RValue rvalue, QualType type) {
+      push_back(CallArg(rvalue, type));
     }
   };
 

clang/test/CodeGen/byval-memcpy-elim.c

@@ -1,20 +0,0 @@
-// RUN: %clang_cc1 -emit-llvm -triple x86_64-apple-darwin10 < %s | FileCheck %s
-
-struct Test1S {
- long NumDecls;
- long X;
- long Y;
-};
-struct Test2S {
- long NumDecls;
- long X;
-};
-
-// Make sure we don't generate extra memcpy for lvalues
-void test1a(struct Test1S, struct Test2S);
-// CHECK: define void @test1(
-// CHECK-NOT: memcpy
-// CHECK: call void @test1a
-void test1(struct Test1S *A, struct Test2S *B) {
-  test1a(*A, *B);
-}