[PATCH, i386] Fix alignment check for AVX-512 masked store

[Ilya Enkovich]

Hi,

This patch fixes wrong alignment check in <avx512>_store<mode>_mask
pattern.  Currently we check a register operand instead of a memory
one.  This fixes segfault on 481.wrf compiled at -O3 for KNL target.
I bootstrapped and tested this patch on x86_64-unknown-linux-gnu.

I got a bunch of new failures:

FAIL: gcc.target/i386/avx512vl-vmovapd-1.c scan-assembler-times vmovapd[ 
\\t]+[^{\n]*%xmm[0-9]+[^\n]*\\){%k[1-7]}(?:\n|[ \\t]+#) 1
FAIL: gcc.target/i386/avx512vl-vmovapd-1.c scan-assembler-times vmovapd[ 
\\t]+[^{\n]*%xmm[0-9]+[^\n]*\\){%k[1-7]}(?:\n|[ \\t]+#) 1
FAIL: gcc.target/i386/avx512vl-vmovapd-1.c scan-assembler-times vmovapd[ 
\\t]+[^{\n]*%ymm[0-9]+[^\n]*\\){%k[1-7]}(?:\n|[ \\t]+#) 1
FAIL: gcc.target/i386/avx512vl-vmovapd-1.c scan-assembler-times vmovapd[ 
\\t]+[^{\n]*%ymm[0-9]+[^\n]*\\){%k[1-7]}(?:\n|[ \\t]+#) 1
FAIL: gcc.target/i386/avx512vl-vmovaps-1.c scan-assembler-times vmovaps[ 
\\t]+[^{\n]*%xmm[0-9]+[^\n]*\\){%k[1-7]}(?:\n|[ \\t]+#) 1
FAIL: gcc.target/i386/avx512vl-vmovaps-1.c scan-assembler-times vmovaps[ 
\\t]+[^{\n]*%xmm[0-9]+[^\n]*\\){%k[1-7]}(?:\n|[ \\t]+#) 1
FAIL: gcc.target/i386/avx512vl-vmovaps-1.c scan-assembler-times vmovaps[ 
\\t]+[^{\n]*%ymm[0-9]+[^\n]*\\){%k[1-7]}(?:\n|[ \\t]+#) 1
FAIL: gcc.target/i386/avx512vl-vmovaps-1.c scan-assembler-times vmovaps[ 
\\t]+[^{\n]*%ymm[0-9]+[^\n]*\\){%k[1-7]}(?:\n|[ \\t]+#) 1

With patch applied test generates vmovup[sd] because memory
references don't have proper alignment set.  Since this is
another bug and it's actually a performance one, I think
this patch should go to trunk.

Thanks,
Ilya
--
gcc/

2015-12-02  Ilya Enkovich  <enkovich....@gmail.com>

        * config/i386/sse.md (<avx512>_store<mode>_mask): Fix
        operand checked for alignment.


diff --git a/gcc/config/i386/sse.md b/gcc/config/i386/sse.md
index e7b517a..d65ed0c 100644
--- a/gcc/config/i386/sse.md
+++ b/gcc/config/i386/sse.md
@@ -1051,7 +1051,7 @@
       sse_suffix = "<ssescalarsize>";
     }
 
-  if (misaligned_operand (operands[1], <MODE>mode))
+  if (misaligned_operand (operands[0], <MODE>mode))
     align = "u";
   else
     align = "a";