[Bug target/115487] New: -march=cascadelake causes spilling

["rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115487

            Bug ID: 115487
           Summary: -march=cascadelake causes spilling
           Product: gcc
           Version: 15.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: rguenth at gcc dot gnu.org
  Target Milestone: ---

When looking at the report of gcc.target/i386/vect-strided-3.c FAILing with
-march=cascadelake I arrived at using -mno-sse4 instead of just -mno-avx
to avoid pextrq from being used instead of movhps.

But then adding -m32 does

        movq    %xmm3, 8(%esp)
        movd    12(%esp), %xmm1
        movd    8(%esp), %xmm0
..
        punpckldq       %xmm1, %xmm0

but only when -march=cascadelake, not with -march=x86-64.  So this confuses
the -march=cascadelake -m32 testresult.  Same with -march=znver2 but not
with -mavx2 -mno-sse4.

diff --git a/gcc/testsuite/gcc.target/i386/vect-strided-3.c
b/gcc/testsuite/gcc.target/i386/vect-strided-3.c
index b462701a0b2..f9c54a6f715 100644
--- a/gcc/testsuite/gcc.target/i386/vect-strided-3.c
+++ b/gcc/testsuite/gcc.target/i386/vect-strided-3.c
@@ -1,5 +1,5 @@
 /* { dg-do compile } */
-/* { dg-options "-O2 -msse2 -mno-avx -fno-tree-slp-vectorize" } */
+/* { dg-options "-O2 -msse2 -mno-sse4 -fno-tree-slp-vectorize" } */

 void foo (int * __restrict a, int *b, int s)
 {