[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, 17 insertions, 13 deletions

diff --git a/lib/Headers/avx512fintrin.h b/lib/Headers/avx512fintrin.h
index 1c19993ff1..55f3fe9609 100644
--- a/lib/Headers/avx512fintrin.h
+++ b/lib/Headers/avx512fintrin.h
@@ -40,9 +40,13 @@ typedef unsigned short __v32hu __attribute__((__vector_size__(64)));
 typedef unsigned long long __v8du __attribute__((__vector_size__(64)));
 typedef unsigned int __v16su __attribute__((__vector_size__(64)));
 
-typedef float __m512 __attribute__((__vector_size__(64)));
-typedef double __m512d __attribute__((__vector_size__(64)));
-typedef long long __m512i __attribute__((__vector_size__(64)));
+typedef float __m512 __attribute__((__vector_size__(64), __aligned__(64)));
+typedef double __m512d __attribute__((__vector_size__(64), __aligned__(64)));
+typedef long long __m512i __attribute__((__vector_size__(64), __aligned__(64)));
+
+typedef float __m512_u __attribute__((__vector_size__(64), __aligned__(1)));
+typedef double __m512d_u __attribute__((__vector_size__(64), __aligned__(1)));
+typedef long long __m512i_u __attribute__((__vector_size__(64), __aligned__(1)));
 
 typedef unsigned char __mmask8;
 typedef unsigned short __mmask16;
@@ -4324,7 +4328,7 @@ static __inline __m512i __DEFAULT_FN_ATTRS512
 _mm512_loadu_si512 (void const *__P)
 {
   struct __loadu_si512 {
-    __m512i __v;
+    __m512i_u __v;
   } __attribute__((__packed__, __may_alias__));
   return ((struct __loadu_si512*)__P)->__v;
 }
@@ -4333,7 +4337,7 @@ static __inline __m512i __DEFAULT_FN_ATTRS512
 _mm512_loadu_epi32 (void const *__P)
 {
   struct __loadu_epi32 {
-    __m512i __v;
+    __m512i_u __v;
   } __attribute__((__packed__, __may_alias__));
   return ((struct __loadu_epi32*)__P)->__v;
 }
@@ -4360,7 +4364,7 @@ static __inline __m512i __DEFAULT_FN_ATTRS512
 _mm512_loadu_epi64 (void const *__P)
 {
   struct __loadu_epi64 {
-    __m512i __v;
+    __m512i_u __v;
   } __attribute__((__packed__, __may_alias__));
   return ((struct __loadu_epi64*)__P)->__v;
 }
@@ -4420,7 +4424,7 @@ static __inline __m512d __DEFAULT_FN_ATTRS512
 _mm512_loadu_pd(void const *__p)
 {
   struct __loadu_pd {
-    __m512d __v;
+    __m512d_u __v;
   } __attribute__((__packed__, __may_alias__));
   return ((struct __loadu_pd*)__p)->__v;
 }
@@ -4429,7 +4433,7 @@ static __inline __m512 __DEFAULT_FN_ATTRS512
 _mm512_loadu_ps(void const *__p)
 {
   struct __loadu_ps {
-    __m512 __v;
+    __m512_u __v;
   } __attribute__((__packed__, __may_alias__));
   return ((struct __loadu_ps*)__p)->__v;
 }
@@ -4504,7 +4508,7 @@ static __inline void __DEFAULT_FN_ATTRS512
 _mm512_storeu_epi64 (void *__P, __m512i __A)
 {
   struct __storeu_epi64 {
-    __m512i __v;
+    __m512i_u __v;
   } __attribute__((__packed__, __may_alias__));
   ((struct __storeu_epi64*)__P)->__v = __A;
 }
@@ -4520,7 +4524,7 @@ static __inline void __DEFAULT_FN_ATTRS512
 _mm512_storeu_si512 (void *__P, __m512i __A)
 {
   struct __storeu_si512 {
-    __m512i __v;
+    __m512i_u __v;
   } __attribute__((__packed__, __may_alias__));
   ((struct __storeu_si512*)__P)->__v = __A;
 }
@@ -4529,7 +4533,7 @@ static __inline void __DEFAULT_FN_ATTRS512
 _mm512_storeu_epi32 (void *__P, __m512i __A)
 {
   struct __storeu_epi32 {
-    __m512i __v;
+    __m512i_u __v;
   } __attribute__((__packed__, __may_alias__));
   ((struct __storeu_epi32*)__P)->__v = __A;
 }
@@ -4551,7 +4555,7 @@ static __inline void __DEFAULT_FN_ATTRS512
 _mm512_storeu_pd(void *__P, __m512d __A)
 {
   struct __storeu_pd {
-    __m512d __v;
+    __m512d_u __v;
   } __attribute__((__packed__, __may_alias__));
   ((struct __storeu_pd*)__P)->__v = __A;
 }
@@ -4567,7 +4571,7 @@ static __inline void __DEFAULT_FN_ATTRS512
 _mm512_storeu_ps(void *__P, __m512 __A)
 {
   struct __storeu_ps {
-    __m512 __v;
+    __m512_u __v;
   } __attribute__((__packed__, __may_alias__));
   ((struct __storeu_ps*)__P)->__v = __A;
 }