[PATCH, i386, AVX-512] Fix AVX-512 broadcast pattern.

[Kirill Yukhin]

Hello,
Patch in the bottom fixes spec2k6/410.bwaves compfail on gcc-5-branch.
AVX-512F broadcasts to ymm are not allowed, we need to use zmm as destination
instead.

I'll commit it to gcc-5 after bootstrap & regtest.

I'll also check if it is needed for upcoming v6

gcc/
        * config/i386/sse.md (define_insn "vec_dup<mode>"): Separate EVEX
        alternative.
gcc/testsuite/
        * gcc.target/i386/avx512f-vbroadcastsd-3.c: New test.

--
Thanks, K

commit b5cc7717310e04b37fc55602d83c16b35b41e875
Author: Kirill Yukhin <kirill.yuk...@intel.com>
Date:   Tue Dec 29 17:02:21 2015 +0300

    Fix 410.bwaves.

diff --git a/gcc/config/i386/sse.md b/gcc/config/i386/sse.md
index 1a87952..316977b8 100644
--- a/gcc/config/i386/sse.md
+++ b/gcc/config/i386/sse.md
@@ -16930,20 +16930,21 @@
    (set_attr "mode" "<sseinsnmode>")])
 
 (define_insn "vec_dup<mode>"
-  [(set (match_operand:AVX_VEC_DUP_MODE 0 "register_operand" "=x,x,v,x")
+  [(set (match_operand:AVX_VEC_DUP_MODE 0 "register_operand" "=x,x,x,v,x")
        (vec_duplicate:AVX_VEC_DUP_MODE
-         (match_operand:<ssescalarmode> 1 "nonimmediate_operand" "m,m,v,?x")))]
+         (match_operand:<ssescalarmode> 1 "nonimmediate_operand" 
"m,m,x,v,?x")))]
   "TARGET_AVX"
   "@
    v<sseintprefix>broadcast<bcstscalarsuff>\t{%1, %0|%0, %1}
    vbroadcast<ssescalarmodesuffix>\t{%1, %0|%0, %1}
    v<sseintprefix>broadcast<bcstscalarsuff>\t{%x1, %0|%0, %x1}
+   v<sseintprefix>broadcast<bcstscalarsuff>\t{%x1, %g0|%g0, %x1}
    #"
   [(set_attr "type" "ssemov")
    (set_attr "prefix_extra" "1")
    (set_attr "prefix" "maybe_evex")
-   (set_attr "isa" "avx2,noavx2,avx2,noavx2")
-   (set_attr "mode" "<sseinsnmode>,V8SF,<sseinsnmode>,V8SF")])
+   (set_attr "isa" "avx2,noavx2,avx2,avx512f,noavx2")
+   (set_attr "mode" "<sseinsnmode>,V8SF,<sseinsnmode>,<sseinsnmode>,V8SF")])
 
 (define_split
   [(set (match_operand:AVX2_VEC_DUP_MODE 0 "register_operand")
diff --git a/gcc/testsuite/gcc.target/i386/avx512f-vbroadcastsd-3.c 
b/gcc/testsuite/gcc.target/i386/avx512f-vbroadcastsd-3.c
new file mode 100644
index 0000000..9e44513
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/avx512f-vbroadcastsd-3.c
@@ -0,0 +1,21 @@
+/* { dg-do compile { target { ! ia32 } } } */
+/* { dg-options "-mavx512f -O2 -ftree-vectorize  -ffixed-xmm0 -ffixed-xmm1 
-ffixed-xmm2 -ffixed-xmm3 -ffixed-xmm4 -ffixed-xmm5 -ffixed-xmm6 -ffixed-xmm7 
-ffixed-xmm8 -ffixed-xmm9 -ffixed-xmm10 -ffixed-xmm11 -ffixed-xmm12 
-ffixed-xmm13 -ffixed-xmm14" } */
+/* { dg-final { scan-assembler-times "vbroadcastsd\[ 
\\t\]+(?:%xmm(?:\[0-9\]|1\[0-5\]),\[ 
\\t\]*%ymm(?:\[0-9\]|1\[0-5\])|%xmm\[0-9\]+,\[ \\t\]*%zmm)" 1 } } */
+
+#include <immintrin.h>
+
+register __m512d z asm ("zmm16"); /* { dg-warning "call-clobbered register 
used for global register variable" } */
+
+double a[10000];
+
+void foo (unsigned N)
+{
+  double d;
+  _mm_store_sd(&d,  _mm256_extractf128_pd (_mm512_extractf64x4_pd (z, 0), 0));
+
+  for (int i=0; i<N; i++)
+    {
+      a[i] = d;
+      a[i] += a[i-4];
+    }
+}