[X86] Add explicit alignment to __m128/__m128i/__m128d/etc. to allow matching of MSVC behavior with #pragma pack.

Summary:
With MSVC, #pragma pack is ignored when there is explicit alignment. This differs from gcc. Clang emulates this difference when compiling for Windows.

It appears that MSVC and its headers consider the __m128/__m128i/__m128d/etc. types to be explicitly aligned and ignores #pragma pack for them. Since we don't have explicit alignment on them in our headers, we don't match the MSVC behavior here.

This patch adds explicit alignment to match this behavior. I'm hoping this won't cause any problems when we're not emulating MSVC. But if someone knows of something that would be different we can swith to conditionally adding the alignment based on _MSC_VER.

I had to add explicitly unaligned types as well so we could use them in the loadu/storeu intrinsics which use __attribute__(__packed__). Using the now explicitly aligned types wouldn't produce align 1 accesses when targeting Windows.

Reviewers: rnk, erichkeane, spatel, RKSimon

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D57961

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@353555 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 8 insertions, 8 deletions

diff --git a/lib/Headers/avx512vlbwintrin.h b/lib/Headers/avx512vlbwintrin.h
index 87e0023e8b..9e85ffd528 100644
--- a/lib/Headers/avx512vlbwintrin.h
+++ b/lib/Headers/avx512vlbwintrin.h
@@ -2301,7 +2301,7 @@ static __inline __m128i __DEFAULT_FN_ATTRS128
 _mm_loadu_epi16 (void const *__P)
 {
   struct __loadu_epi16 {
-    __m128i __v;
+    __m128i_u __v;
   } __attribute__((__packed__, __may_alias__));
   return ((struct __loadu_epi16*)__P)->__v;
 }
@@ -2327,7 +2327,7 @@ static __inline __m256i __DEFAULT_FN_ATTRS256
 _mm256_loadu_epi16 (void const *__P)
 {
   struct __loadu_epi16 {
-    __m256i __v;
+    __m256i_u __v;
   } __attribute__((__packed__, __may_alias__));
   return ((struct __loadu_epi16*)__P)->__v;
 }
@@ -2353,7 +2353,7 @@ static __inline __m128i __DEFAULT_FN_ATTRS128
 _mm_loadu_epi8 (void const *__P)
 {
   struct __loadu_epi8 {
-    __m128i __v;
+    __m128i_u __v;
   } __attribute__((__packed__, __may_alias__));
   return ((struct __loadu_epi8*)__P)->__v;
 }
@@ -2379,7 +2379,7 @@ static __inline __m256i __DEFAULT_FN_ATTRS256
 _mm256_loadu_epi8 (void const *__P)
 {
   struct __loadu_epi8 {
-    __m256i __v;
+    __m256i_u __v;
   } __attribute__((__packed__, __may_alias__));
   return ((struct __loadu_epi8*)__P)->__v;
 }
@@ -2405,7 +2405,7 @@ static __inline void __DEFAULT_FN_ATTRS128
 _mm_storeu_epi16 (void *__P, __m128i __A)
 {
   struct __storeu_epi16 {
-    __m128i __v;
+    __m128i_u __v;
   } __attribute__((__packed__, __may_alias__));
   ((struct __storeu_epi16*)__P)->__v = __A;
 }
@@ -2422,7 +2422,7 @@ static __inline void __DEFAULT_FN_ATTRS256
 _mm256_storeu_epi16 (void *__P, __m256i __A)
 {
   struct __storeu_epi16 {
-    __m256i __v;
+    __m256i_u __v;
   } __attribute__((__packed__, __may_alias__));
   ((struct __storeu_epi16*)__P)->__v = __A;
 }
@@ -2439,7 +2439,7 @@ static __inline void __DEFAULT_FN_ATTRS128
 _mm_storeu_epi8 (void *__P, __m128i __A)
 {
   struct __storeu_epi8 {
-    __m128i __v;
+    __m128i_u __v;
   } __attribute__((__packed__, __may_alias__));
   ((struct __storeu_epi8*)__P)->__v = __A;
 }
@@ -2456,7 +2456,7 @@ static __inline void __DEFAULT_FN_ATTRS256
 _mm256_storeu_epi8 (void *__P, __m256i __A)
 {
   struct __storeu_epi8 {
-    __m256i __v;
+    __m256i_u __v;
   } __attribute__((__packed__, __may_alias__));
   ((struct __storeu_epi8*)__P)->__v = __A;
 }