[PATCH] Override prefer-vector-width= in x86 simd clones (PR target/93089)

[Jakub Jelinek]

Hi!

As mentioned in the previous mail, this is what I intend to commit if/when
the prefer-vector-width= in target attribute patch makes it in.

Bootstrapped/regtested on x86_64-linux and i686-linux.

2020-01-03  Jakub Jelinek  <ja...@redhat.com>

        PR target/93089
        * config/i386/i386-options.c (ix86_simd_clone_adjust): If
        TARGET_PREFER_AVX128, use prefer-vector-width=256 for 'c' and 'd'
        simd clones.  If TARGET_PREFER_AVX256, use prefer-vector-width=512
        for 'e' simd clones.

        * gcc.target/i386/pr93089-2.c: New test.
        * gcc.target/i386/pr93089-3.c: New test.

--- gcc/config/i386/i386-options.c.jj   2020-01-02 14:00:40.299515822 +0100
+++ gcc/config/i386/i386-options.c      2020-01-02 15:13:00.067579822 +0100
@@ -2950,15 +2950,36 @@ ix86_simd_clone_adjust (struct cgraph_no
        str = "sse2";
       break;
     case 'c':
-      if (!TARGET_AVX)
+      if (TARGET_PREFER_AVX128)
+       {
+         if (!TARGET_AVX)
+           str = "avx,prefer-vector-width=256";
+         else
+           str = "prefer-vector-width=256";
+       }
+      else if (!TARGET_AVX)
        str = "avx";
       break;
     case 'd':
-      if (!TARGET_AVX2)
+      if (TARGET_PREFER_AVX128)
+       {
+         if (!TARGET_AVX2)
+           str = "avx2,prefer-vector-width=256";
+         else
+           str = "prefer-vector-width=256";
+       }
+      else if (!TARGET_AVX2)
        str = "avx2";
       break;
     case 'e':
-      if (!TARGET_AVX512F)
+      if (TARGET_PREFER_AVX256)
+       {
+         if (!TARGET_AVX512F)
+           str = "avx512f,prefer-vector-width=512";
+         else
+           str = "prefer-vector-width=512";
+       }
+      else if (!TARGET_AVX512F)
        str = "avx512f";
       break;
     default:
--- gcc/testsuite/gcc.target/i386/pr93089-2.c.jj        2020-01-02 
15:19:01.345119189 +0100
+++ gcc/testsuite/gcc.target/i386/pr93089-2.c   2020-01-02 15:18:34.767520897 
+0100
@@ -0,0 +1,12 @@
+/* PR target/93089 */
+/* { dg-do compile } */
+/* { dg-options "-O2 -fopenmp-simd -mtune=znver1" } */
+/* { dg-final { scan-assembler "vmulps\[^\n\r]*zmm" } } */
+/* { dg-final { scan-assembler "vmulps\[^\n\r]*ymm" } } */
+
+#pragma omp declare simd notinbranch
+float
+foo (float x, float y)
+{
+  return x * y;
+}
--- gcc/testsuite/gcc.target/i386/pr93089-3.c.jj        2020-01-02 
15:19:08.460011650 +0100
+++ gcc/testsuite/gcc.target/i386/pr93089-3.c   2020-01-02 15:19:15.734901684 
+0100
@@ -0,0 +1,12 @@
+/* PR target/93089 */
+/* { dg-do compile } */
+/* { dg-options "-O2 -fopenmp-simd -mtune=skylake-avx512" } */
+/* { dg-final { scan-assembler "vmulps\[^\n\r]*zmm" } } */
+/* { dg-final { scan-assembler "vmulps\[^\n\r]*ymm" } } */
+
+#pragma omp declare simd notinbranch
+float
+foo (float x, float y)
+{
+  return x * y;
+}

        Jakub