MS ABI: Use musttail for thunk IR generation
This allows us to perfectly forward non-trivial arguments that use
inalloca.
We still can't forward non-trivial arguments through thunks when we have
a covariant return type with a non-trivial adjustment. This would
require emitting an extra copy, which is non-conforming anyway.
llvm-svn: 208927
diff --git a/clang/test/CodeGenCXX/microsoft-abi-virtual-member-pointers.cpp b/clang/test/CodeGenCXX/microsoft-abi-virtual-member-pointers.cpp
index c069e2d..974953c 100644
--- a/clang/test/CodeGenCXX/microsoft-abi-virtual-member-pointers.cpp
+++ b/clang/test/CodeGenCXX/microsoft-abi-virtual-member-pointers.cpp
@@ -5,10 +5,19 @@
int x, y, z;
};
+// U is not trivially copyable, and requires inalloca to pass by value.
+struct U {
+ int u;
+ U();
+ ~U();
+ U(const U &);
+};
+
struct C {
virtual void foo();
virtual int bar(int, double);
virtual S baz(int);
+ virtual S qux(U);
};
namespace {
@@ -31,6 +40,10 @@
void (D::*ptr4)();
ptr4 = &D::foo;
+ S (C::*ptr5)(U);
+ ptr5 = &C::qux;
+
+
// CHECK32-LABEL: define void @"\01?f@@YAXXZ"()
// CHECK32: store i8* bitcast (void (%struct.C*)* @"\01??_9C@@$BA@AE" to i8*), i8** %ptr
// CHECK32: store i8* bitcast (i32 (%struct.C*, i32, double)* @"\01??_9C@@$B3AE" to i8*), i8** %ptr2
@@ -51,14 +64,14 @@
// CHECK32-LABEL: define linkonce_odr x86_thiscallcc void @"\01??_9C@@$BA@AE"(%struct.C* %this) unnamed_addr
// CHECK32: [[VPTR:%.*]] = getelementptr inbounds void (%struct.C*)** %{{.*}}, i64 0
// CHECK32: [[CALLEE:%.*]] = load void (%struct.C*)** [[VPTR]]
-// CHECK32: call x86_thiscallcc void [[CALLEE]](%struct.C* %{{.*}})
+// CHECK32: musttail call x86_thiscallcc void [[CALLEE]](%struct.C* %{{.*}})
// CHECK32: ret void
// CHECK32: }
//
// CHECK64-LABEL: define linkonce_odr void @"\01??_9C@@$BA@AA"(%struct.C* %this) unnamed_addr
// CHECK64: [[VPTR:%.*]] = getelementptr inbounds void (%struct.C*)** %{{.*}}, i64 0
// CHECK64: [[CALLEE:%.*]] = load void (%struct.C*)** [[VPTR]]
-// CHECK64: call void [[CALLEE]](%struct.C* %{{.*}})
+// CHECK64: musttail call void [[CALLEE]](%struct.C* %{{.*}})
// CHECK64: ret void
// CHECK64: }
@@ -66,14 +79,14 @@
// CHECK32-LABEL: define linkonce_odr x86_thiscallcc i32 @"\01??_9C@@$B3AE"(%struct.C* %this, i32, double) unnamed_addr
// CHECK32: [[VPTR:%.*]] = getelementptr inbounds i32 (%struct.C*, i32, double)** %{{.*}}, i64 1
// CHECK32: [[CALLEE:%.*]] = load i32 (%struct.C*, i32, double)** [[VPTR]]
-// CHECK32: [[CALL:%.*]] = call x86_thiscallcc i32 [[CALLEE]](%struct.C* %{{.*}}, i32 %{{.*}}, double %{{.*}})
+// CHECK32: [[CALL:%.*]] = musttail call x86_thiscallcc i32 [[CALLEE]](%struct.C* %{{.*}}, i32 %{{.*}}, double %{{.*}})
// CHECK32: ret i32 [[CALL]]
// CHECK32: }
//
// CHECK64-LABEL: define linkonce_odr i32 @"\01??_9C@@$B7AA"(%struct.C* %this, i32, double) unnamed_addr
// CHECK64: [[VPTR:%.*]] = getelementptr inbounds i32 (%struct.C*, i32, double)** %{{.*}}, i64 1
// CHECK64: [[CALLEE:%.*]] = load i32 (%struct.C*, i32, double)** [[VPTR]]
-// CHECK64: [[CALL:%.*]] = call i32 [[CALLEE]](%struct.C* %{{.*}}, i32 %{{.*}}, double %{{.*}})
+// CHECK64: [[CALL:%.*]] = musttail call i32 [[CALLEE]](%struct.C* %{{.*}}, i32 %{{.*}}, double %{{.*}})
// CHECK64: ret i32 [[CALL]]
// CHECK64: }
@@ -81,14 +94,14 @@
// CHECK32-LABEL: define linkonce_odr x86_thiscallcc void @"\01??_9C@@$B7AE"(%struct.C* %this, %struct.S* noalias sret %agg.result, i32) unnamed_addr
// CHECK32: [[VPTR:%.*]] = getelementptr inbounds void (%struct.C*, %struct.S*, i32)** %{{.*}}, i64 2
// CHECK32: [[CALLEE:%.*]] = load void (%struct.C*, %struct.S*, i32)** [[VPTR]]
-// CHECK32: call x86_thiscallcc void [[CALLEE]](%struct.C* %{{.*}}, %struct.S* sret %agg.result, i32 %{{.*}})
+// CHECK32: musttail call x86_thiscallcc void [[CALLEE]](%struct.C* %{{.*}}, %struct.S* sret %agg.result, i32 %{{.*}})
// CHECK32: ret void
// CHECK32: }
//
// CHECK64-LABEL: define linkonce_odr void @"\01??_9C@@$BBA@AA"(%struct.C* %this, %struct.S* noalias sret %agg.result, i32) unnamed_addr
// CHECK64: [[VPTR:%.*]] = getelementptr inbounds void (%struct.C*, %struct.S*, i32)** %{{.*}}, i64 2
// CHECK64: [[CALLEE:%.*]] = load void (%struct.C*, %struct.S*, i32)** [[VPTR]]
-// CHECK64: call void [[CALLEE]](%struct.C* %{{.*}}, %struct.S* sret %agg.result, i32 %{{.*}})
+// CHECK64: musttail call void [[CALLEE]](%struct.C* %{{.*}}, %struct.S* sret %agg.result, i32 %{{.*}})
// CHECK64: ret void
// CHECK64: }
@@ -96,13 +109,28 @@
// CHECK32-LABEL: define internal x86_thiscallcc void @"\01??_9D@?A@@$BA@AE"(%"struct.(anonymous namespace)::D"* %this) unnamed_addr
// CHECK32: [[VPTR:%.*]] = getelementptr inbounds void (%"struct.(anonymous namespace)::D"*)** %{{.*}}, i64 0
// CHECK32: [[CALLEE:%.*]] = load void (%"struct.(anonymous namespace)::D"*)** [[VPTR]]
-// CHECK32: call x86_thiscallcc void [[CALLEE]](%"struct.(anonymous namespace)::D"* %{{.*}})
+// CHECK32: musttail call x86_thiscallcc void [[CALLEE]](%"struct.(anonymous namespace)::D"* %{{.*}})
// CHECK32: ret void
// CHECK32: }
//
// CHECK64-LABEL: define internal void @"\01??_9D@?A@@$BA@AA"(%"struct.(anonymous namespace)::D"* %this) unnamed_addr
// CHECK64: [[VPTR:%.*]] = getelementptr inbounds void (%"struct.(anonymous namespace)::D"*)** %{{.*}}, i64 0
// CHECK64: [[CALLEE:%.*]] = load void (%"struct.(anonymous namespace)::D"*)** [[VPTR]]
-// CHECK64: call void [[CALLEE]](%"struct.(anonymous namespace)::D"* %{{.*}})
+// CHECK64: musttail call void [[CALLEE]](%"struct.(anonymous namespace)::D"* %{{.*}})
+// CHECK64: ret void
+// CHECK64: }
+
+// Thunk for calling the fourth virtual function in C, taking a struct parameter and returning a struct.
+// CHECK32-LABEL: define linkonce_odr x86_thiscallcc %struct.S* @"\01??_9C@@$BM@AE"(%struct.C* %this, <{ %struct.S*, %struct.U }>* inalloca) unnamed_addr
+// CHECK32: [[VPTR:%.*]] = getelementptr inbounds %struct.S* (%struct.C*, <{ %struct.S*, %struct.U }>*)** %{{.*}}, i64 3
+// CHECK32: [[CALLEE:%.*]] = load %struct.S* (%struct.C*, <{ %struct.S*, %struct.U }>*)** [[VPTR]]
+// CHECK32: [[CALL:%.*]] = musttail call x86_thiscallcc %struct.S* [[CALLEE]](%struct.C* %this, <{ %struct.S*, %struct.U }>* inalloca %{{.*}})
+// CHECK32: ret %struct.S* [[CALL]]
+// CHECK32: }
+//
+// CHECK64-LABEL: define linkonce_odr void @"\01??_9C@@$BBI@AA"(%struct.C* %this, %struct.S* noalias sret %agg.result, %struct.U*) unnamed_addr
+// CHECK64: [[VPTR:%.*]] = getelementptr inbounds void (%struct.C*, %struct.S*, %struct.U*)** %{{.*}}, i64 3
+// CHECK64: [[CALLEE:%.*]] = load void (%struct.C*, %struct.S*, %struct.U*)** [[VPTR]]
+// CHECK64: musttail call void [[CALLEE]](%struct.C* %this, %struct.S* sret %agg.result, %struct.U* %{{.*}})
// CHECK64: ret void
// CHECK64: }