diff mbox

[i386] PR 70118: Fix ubsan warning on SSE2 loadl_epi64 and storel_epi64

Message ID 201611271829.22468.linux@carewolf.com
State Superseded
Headers show

Commit Message

Allan Sandfeld Jensen Nov. 27, 2016, 5:29 p.m. UTC 
On Sunday 27 November 2016, Marc Glisse wrote:
> On Sat, 26 Nov 2016, Allan Sandfeld Jensen wrote:

> > Use the recently introduced unaligned variant of __m128i and add a

> > similar __m64 and use those to make it clear these two intrinsics

> > require neither 128- bit nor 64-bit alignment.

> 

> Thanks for doing this. You'll want Uros or Kirill to review your patch.

> There are probably several more places that could do with an unaligned

> fix, but we don't have to find them all at once.

> First I found it strange to use __m64, but then it actually seems like a

> good call to use a type that is not just aligned(1) but also may_alias.

> 

> +  *(__m64_u *)__P = __m64(((__v2di)__B)[0]);

> 

> gcc complains about this syntax for me, it wants parentheses around

> __m64... Did it pass the testsuite for you?


Fixed, it now matches the move just below.
diff mbox

Patch

Index: gcc/config/i386/emmintrin.h
===================================================================
--- gcc/config/i386/emmintrin.h	(revision 242892)
+++ gcc/config/i386/emmintrin.h	(working copy)
@@ -703,9 +703,9 @@ 
 }
 
 extern __inline __m128i __attribute__((__gnu_inline__, __always_inline__, __artificial__))
-_mm_loadl_epi64 (__m128i const *__P)
+_mm_loadl_epi64 (__m128i_u const *__P)
 {
-  return _mm_set_epi64 ((__m64)0LL, *(__m64 *)__P);
+  return _mm_set_epi64 ((__m64)0LL, *(__m64_u *)__P);
 }
 
 extern __inline void __attribute__((__gnu_inline__, __always_inline__, __artificial__))
@@ -721,9 +721,9 @@ 
 }
 
 extern __inline void __attribute__((__gnu_inline__, __always_inline__, __artificial__))
-_mm_storel_epi64 (__m128i *__P, __m128i __B)
+_mm_storel_epi64 (__m128i_u *__P, __m128i __B)
 {
-  *(long long *)__P = ((__v2di)__B)[0];
+  *(__m64_u *)__P = (__m64) ((__v2di)__B)[0];
 }
 
 extern __inline __m64 __attribute__((__gnu_inline__, __always_inline__, __artificial__))
Index: gcc/config/i386/mmintrin.h
===================================================================
--- gcc/config/i386/mmintrin.h	(revision 242892)
+++ gcc/config/i386/mmintrin.h	(working copy)
@@ -37,6 +37,9 @@ 
    vector types, and their scalar components.  */
 typedef int __m64 __attribute__ ((__vector_size__ (8), __may_alias__));
 
+/* Unaligned version of the same type  */
+typedef int __m64_u __attribute__ ((__vector_size__ (8), __may_alias__, __aligned__ (1)));
+
 /* Internal data types for implementing the intrinsics.  */
 typedef int __v2si __attribute__ ((__vector_size__ (8)));
 typedef short __v4hi __attribute__ ((__vector_size__ (8)));