[CodeGen] Don't crash classifying a union of an AVX vector and an int

We forgot to run postMerge after decided that the union had to be
classified as MEMORY.  This left us with Lo == MEMORY and Hi == SSEUp
which is an invalid combination.

This fixes PR24021.

Differential Revision: http://reviews.llvm.org/D10908

llvm-svn: 241666

2 files changed, 11 insertions, 0 deletions

diff --git a/clang/lib/CodeGen/TargetInfo.cpp b/clang/lib/CodeGen/TargetInfo.cpp
index e5ba200e1c5..dbb9e8d9039 100644
--- a/clang/lib/CodeGen/TargetInfo.cpp
+++ b/clang/lib/CodeGen/TargetInfo.cpp
@@ -2094,11 +2094,13 @@ void X86_64ABIInfo::classify(QualType Ty, uint64_t OffsetBase,
       //
       if (Size > 128 && getContext().getTypeSize(i->getType()) != 256) {
         Lo = Memory;
+        postMerge(Size, Lo, Hi);
         return;
       }
       // Note, skip this test for bit-fields, see below.
       if (!BitField && Offset % getContext().getTypeAlign(i->getType())) {
         Lo = Memory;
+        postMerge(Size, Lo, Hi);
         return;
       }
 
diff --git a/clang/test/CodeGenCXX/x86_64-arguments-avx.cpp b/clang/test/CodeGenCXX/x86_64-arguments-avx.cpp
index 29e693451d1..2933d9445b7 100644
--- a/clang/test/CodeGenCXX/x86_64-arguments-avx.cpp
+++ b/clang/test/CodeGenCXX/x86_64-arguments-avx.cpp
@@ -50,3 +50,12 @@ UU2 PR23082(UU2 x) {
   return x;
 }
 }
+
+namespace test3 {
+union U {
+  __attribute__((__vector_size__(32))) float f1;
+  int f2;
+};
+// CHECK: define i32 @_ZN5test31fENS_1UE({{.*}}* byval align 32
+int f(U u) { return u.f2; }
+}