CodeGen: tweak struct ABI handling

Cygwin and MinGW fail to conform to the underlying system's structure passing
ABI.  Make the check more precise to ensure that we correctly generate code for
the itanium environment.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@222626 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/CodeGen/TargetInfo.cpp b/lib/CodeGen/TargetInfo.cpp
index be34bf0f9f0cd190036634c785da6726024582b1..3ad8bd950c61af0c9f1e2c2af3ddb1ddd62ab8d3 100644 (file)
--- a/lib/CodeGen/TargetInfo.cpp
+++ b/lib/CodeGen/TargetInfo.cpp
@@ -7207,7 +7207,7 @@ const TargetCodeGenInfo &CodeGenModule::getTargetCodeGenInfo() {
     bool IsDarwinVectorABI = Triple.isOSDarwin();
     bool IsSmallStructInRegABI =
         X86_32TargetCodeGenInfo::isStructReturnInRegABI(Triple, CodeGenOpts);
-    bool IsWin32FloatStructABI = Triple.isWindowsMSVCEnvironment();
+    bool IsWin32FloatStructABI = Triple.isOSWindows() && !Triple.isOSCygMing();
 
     if (Triple.getOS() == llvm::Triple::Win32) {
       return *(TheTargetCodeGenInfo =

diff --git a/test/CodeGen/windows-struct-abi.c b/test/CodeGen/windows-struct-abi.c
new file mode 100644 (file)
index 0000000..ec4bab6
--- /dev/null
+++ b/test/CodeGen/windows-struct-abi.c
@@ -0,0 +1,27 @@
+// RUN: %clang_cc1 -triple i686-windows-itanium -emit-llvm -o - %s | FileCheck %s
+
+struct f1 {
+  float f;
+};
+
+struct f1 return_f1(void) { while (1); }
+
+// CHECK: define void @return_f1(%struct.f1* noalias sret %agg.result)
+
+void receive_f1(struct f1 a0) { }
+
+// CHECK: define void @receive_f1(%struct.f1* byval align 4 %a0)
+
+struct f2 {
+  float f;
+  float g;
+};
+
+struct f2 return_f2(void) { while (1); }
+
+// CHECK: define void @return_f2(%struct.f2* noalias sret %agg.result)
+
+void receive_f2(struct f2 a0) { }
+
+// CHECK: define void @receive_f2(%struct.f2* byval align 4 %a0)
+