MS ABI x64: Don't destroy arguments twice on x64

We were destroying them in the callee, and then again in the caller.  We
should use an EH-only cleanup and disable it at the point of the call
for win64, even though we don't use inalloca.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@207733 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/CodeGen/CGCall.cpp b/lib/CodeGen/CGCall.cpp
index e82b6defa6b9ac0e7db16d7109ab6e7d5c648393..4428b9631626d8f0d0092d54e7205be468b7573f 100644 (file)
--- a/lib/CodeGen/CGCall.cpp
+++ b/lib/CodeGen/CGCall.cpp
@@ -2286,16 +2286,23 @@ void CodeGenFunction::EmitCallArg(CallArgList &args, const Expr *E,
   // In the Microsoft C++ ABI, aggregate arguments are destructed by the callee.
   // However, we still have to push an EH-only cleanup in case we unwind before
   // we make it to the call.
-  if (HasAggregateEvalKind && args.isUsingInAlloca()) {
-    assert(getTarget().getTriple().getArch() == llvm::Triple::x86);
-    AggValueSlot Slot = createPlaceholderSlot(*this, type);
+  if (HasAggregateEvalKind &&
+      CGM.getTarget().getCXXABI().areArgsDestroyedLeftToRightInCallee()) {
+    // If we're using inalloca, use the argument memory.  Otherwise, use a
+    // temporary.  Either way, the aggregate is destroyed externally in the
+    // callee.
+    AggValueSlot Slot;
+    if (args.isUsingInAlloca())
+      Slot = createPlaceholderSlot(*this, type);
+    else
+      Slot = CreateAggTemp(type, "agg.tmp");
     Slot.setExternallyDestructed();
     EmitAggExpr(E, Slot);
     RValue RV = Slot.asRValue();
     args.add(RV, type);
 
     const CXXRecordDecl *RD = type->getAsCXXRecordDecl();
-    if (RD->hasNonTrivialDestructor()) {
+    if (RD && RD->hasNonTrivialDestructor()) {
       // Create a no-op GEP between the placeholder and the cleanup so we can
       // RAUW it successfully.  It also serves as a marker of the first
       // instruction where the cleanup is active.

diff --git a/test/CodeGenCXX/microsoft-abi-arg-order.cpp b/test/CodeGenCXX/microsoft-abi-arg-order.cpp
index 01f6f47667b4011cf0dd235d687b52b321394afc..d26a515c85e59bf93d7846f253d4d0c9dab9b477 100644 (file)
--- a/test/CodeGenCXX/microsoft-abi-arg-order.cpp
+++ b/test/CodeGenCXX/microsoft-abi-arg-order.cpp
@@ -1,4 +1,5 @@
-// RUN: %clang_cc1 -mconstructor-aliases -std=c++11 -fexceptions -emit-llvm %s -o - -triple=i386-pc-win32 | FileCheck %s
+// RUN: %clang_cc1 -mconstructor-aliases -std=c++11 -fexceptions -emit-llvm %s -o - -triple=i386-pc-win32 | FileCheck %s -check-prefix=X86
+// RUN: %clang_cc1 -mconstructor-aliases -std=c++11 -fexceptions -emit-llvm %s -o - -triple=x86_64-pc-win32 | FileCheck %s -check-prefix=X64
 
 struct A {
   A(int a);
@@ -11,15 +12,22 @@ void foo(A a, A b, A c) {
 
 // Order of destruction should be left to right.
 //
-// CHECK-LABEL: define void @"\01?foo@@YAXUA@@00@Z"
-// CHECK:          ([[argmem_ty:<{ %struct.A, %struct.A, %struct.A }>]]* inalloca)
-// CHECK: %[[a:[^ ]*]] = getelementptr inbounds [[argmem_ty]]* %0, i32 0, i32 0
-// CHECK: %[[b:[^ ]*]] = getelementptr inbounds [[argmem_ty]]* %0, i32 0, i32 1
-// CHECK: %[[c:[^ ]*]] = getelementptr inbounds [[argmem_ty]]* %0, i32 0, i32 2
-// CHECK: call x86_thiscallcc void @"\01??1A@@QAE@XZ"(%struct.A* %[[a]])
-// CHECK: call x86_thiscallcc void @"\01??1A@@QAE@XZ"(%struct.A* %[[b]])
-// CHECK: call x86_thiscallcc void @"\01??1A@@QAE@XZ"(%struct.A* %[[c]])
-// CHECK: ret void
+// X86-LABEL: define void @"\01?foo@@YAXUA@@00@Z"
+// X86:          ([[argmem_ty:<{ %struct.A, %struct.A, %struct.A }>]]* inalloca)
+// X86: %[[a:[^ ]*]] = getelementptr inbounds [[argmem_ty]]* %0, i32 0, i32 0
+// X86: %[[b:[^ ]*]] = getelementptr inbounds [[argmem_ty]]* %0, i32 0, i32 1
+// X86: %[[c:[^ ]*]] = getelementptr inbounds [[argmem_ty]]* %0, i32 0, i32 2
+// X86: call x86_thiscallcc void @"\01??1A@@QAE@XZ"(%struct.A* %[[a]])
+// X86: call x86_thiscallcc void @"\01??1A@@QAE@XZ"(%struct.A* %[[b]])
+// X86: call x86_thiscallcc void @"\01??1A@@QAE@XZ"(%struct.A* %[[c]])
+// X86: ret void
+
+// X64-LABEL: define void @"\01?foo@@YAXUA@@00@Z"
+// X64:         (%struct.A* %[[a:[^,]*]], %struct.A* %[[b:[^,]*]], %struct.A* %[[c:[^)]*]])
+// X64: call void @"\01??1A@@QEAA@XZ"(%struct.A* %[[a]])
+// X64: call void @"\01??1A@@QEAA@XZ"(%struct.A* %[[b]])
+// X64: call void @"\01??1A@@QEAA@XZ"(%struct.A* %[[c]])
+// X64: ret void
 
 
 void call_foo() {
@@ -29,22 +37,37 @@ void call_foo() {
 // Order of evaluation should be right to left, and we should clean up the right
 // things as we unwind.
 //
-// CHECK-LABEL: define void @"\01?call_foo@@YAXXZ"()
-// CHECK: call i8* @llvm.stacksave()
-// CHECK: %[[argmem:[^ ]*]] = alloca inalloca [[argmem_ty]]
-// CHECK: %[[arg3:[^ ]*]] = getelementptr inbounds [[argmem_ty]]* %[[argmem]], i32 0, i32 2
-// CHECK: invoke x86_thiscallcc %struct.A* @"\01??0A@@QAE@H@Z"(%struct.A* %[[arg3]], i32 3)
-// CHECK: %[[arg2:[^ ]*]] = getelementptr inbounds [[argmem_ty]]* %[[argmem]], i32 0, i32 1
-// CHECK: invoke x86_thiscallcc %struct.A* @"\01??0A@@QAE@H@Z"(%struct.A* %[[arg2]], i32 2)
-// CHECK: %[[arg1:[^ ]*]] = getelementptr inbounds [[argmem_ty]]* %[[argmem]], i32 0, i32 0
-// CHECK: invoke x86_thiscallcc %struct.A* @"\01??0A@@QAE@H@Z"(%struct.A* %[[arg1]], i32 1)
-// CHECK: invoke void @"\01?foo@@YAXUA@@00@Z"([[argmem_ty]]* inalloca %[[argmem]])
-// CHECK: call void @llvm.stackrestore
-// CHECK: ret void
+// X86-LABEL: define void @"\01?call_foo@@YAXXZ"()
+// X86: call i8* @llvm.stacksave()
+// X86: %[[argmem:[^ ]*]] = alloca inalloca [[argmem_ty]]
+// X86: %[[arg3:[^ ]*]] = getelementptr inbounds [[argmem_ty]]* %[[argmem]], i32 0, i32 2
+// X86: invoke x86_thiscallcc %struct.A* @"\01??0A@@QAE@H@Z"(%struct.A* %[[arg3]], i32 3)
+// X86: %[[arg2:[^ ]*]] = getelementptr inbounds [[argmem_ty]]* %[[argmem]], i32 0, i32 1
+// X86: invoke x86_thiscallcc %struct.A* @"\01??0A@@QAE@H@Z"(%struct.A* %[[arg2]], i32 2)
+// X86: %[[arg1:[^ ]*]] = getelementptr inbounds [[argmem_ty]]* %[[argmem]], i32 0, i32 0
+// X86: invoke x86_thiscallcc %struct.A* @"\01??0A@@QAE@H@Z"(%struct.A* %[[arg1]], i32 1)
+// X86: invoke void @"\01?foo@@YAXUA@@00@Z"([[argmem_ty]]* inalloca %[[argmem]])
+// X86: call void @llvm.stackrestore
+// X86: ret void
+//
+//   lpad2:
+// X86: call x86_thiscallcc void @"\01??1A@@QAE@XZ"(%struct.A* %[[arg2]])
+// X86: br label
+//
+//   ehcleanup:
+// X86: call x86_thiscallcc void @"\01??1A@@QAE@XZ"(%struct.A* %[[arg3]])
+
+// X64-LABEL: define void @"\01?call_foo@@YAXXZ"()
+// X64: call %struct.A* @"\01??0A@@QEAA@H@Z"(%struct.A* %[[arg3:[^,]*]], i32 3)
+// X64: invoke %struct.A* @"\01??0A@@QEAA@H@Z"(%struct.A* %[[arg2:[^,]*]], i32 2)
+// X64: invoke %struct.A* @"\01??0A@@QEAA@H@Z"(%struct.A* %[[arg1:[^,]*]], i32 1)
+// X64: call void @"\01?foo@@YAXUA@@00@Z"
+// X64:       (%struct.A* %[[arg1]], %struct.A* %[[arg2]], %struct.A* %[[arg3]])
+// X64: ret void
 //
 //   lpad2:
-// CHECK: call x86_thiscallcc void @"\01??1A@@QAE@XZ"(%struct.A* %[[arg2]])
-// CHECK: br label
+// X64: call void @"\01??1A@@QEAA@XZ"(%struct.A* %[[arg2]])
+// X64: br label
 //
 //   ehcleanup:
-// CHECK: call x86_thiscallcc void @"\01??1A@@QAE@XZ"(%struct.A* %[[arg3]])
+// X64: call void @"\01??1A@@QEAA@XZ"(%struct.A* %[[arg3]])