Hello!
There is no point in trying to vectorize with 256bit vector sizes when
we prefer 128bit vectors. Also, cleanup ix86_preferred_simd_mode and
return word_mode for DFmode without SSE2.
2011-05-09 Uros Bizjak <ubiz...@gmail.com>
* config/i386/i386.c (ix86_autovectorize_vector_sizes): Return 0
for !flag_prefer_avx128.
(ix86_preferred_simd_mode): Return word_mode for DFmode without SSE2.
Tested on x86_64-pc-linux-gnu {,-m32}, committed to mainline SVN.
Uros.
Index: i386.c
===================================================================
--- i386.c (revision 173590)
+++ i386.c (working copy)
@@ -35118,32 +35118,38 @@ has_dispatch (rtx insn, int action)
static enum machine_mode
ix86_preferred_simd_mode (enum machine_mode mode)
{
- /* Disable double precision vectorizer if needed. */
- if (mode == DFmode && !TARGET_VECTORIZE_DOUBLE)
- return word_mode;
-
- if (!TARGET_AVX && !TARGET_SSE)
+ if (!TARGET_SSE)
return word_mode;
switch (mode)
{
- case SFmode:
- return (TARGET_AVX && !flag_prefer_avx128) ? V8SFmode : V4SFmode;
- case DFmode:
- return (TARGET_AVX && !flag_prefer_avx128) ? V4DFmode : V2DFmode;
- case DImode:
- return V2DImode;
- case SImode:
- return V4SImode;
- case HImode:
- return V8HImode;
case QImode:
return V16QImode;
+ case HImode:
+ return V8HImode;
+ case SImode:
+ return V4SImode;
+ case DImode:
+ return V2DImode;
- default:;
- }
+ case SFmode:
+ if (TARGET_AVX && !flag_prefer_avx128)
+ return V8SFmode;
+ else
+ return V4SFmode;
- return word_mode;
+ case DFmode:
+ if (!TARGET_VECTORIZE_DOUBLE)
+ return word_mode;
+ else if (TARGET_AVX && !flag_prefer_avx128)
+ return V4DFmode;
+ else if (TARGET_SSE2)
+ return V2DFmode;
+ /* FALLTHRU */
+
+ default:
+ return word_mode;
+ }
}
/* If AVX is enabled then try vectorizing with both 256bit and 128bit
@@ -35152,7 +35158,7 @@ ix86_preferred_simd_mode (enum machine_m
static unsigned int
ix86_autovectorize_vector_sizes (void)
{
- return TARGET_AVX ? 32 | 16 : 0;
+ return (TARGET_AVX && !flag_prefer_avx128) ? 32 | 16 : 0;
}
/* Initialize the GCC target structure. */
