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.

llvm-svn: 222626

diff --git a/clang/lib/CodeGen/TargetInfo.cpp b/clang/lib/CodeGen/TargetInfo.cpp
index be34bf0..3ad8bd9 100644 (file)
--- a/clang/lib/CodeGen/TargetInfo.cpp
+++ b/clang/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/clang/test/CodeGen/windows-struct-abi.c b/clang/test/CodeGen/windows-struct-abi.c
new file mode 100644 (file)
index 0000000..ec4bab6
--- /dev/null
+++ b/clang/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)
+