[gcc/devel/c++-coroutines] Adjust testcase.

[Iain D Sandoe]

https://gcc.gnu.org/g:995bb851ffee659cb86aa24bf36ad5bb5d36da7b

commit 995bb851ffee659cb86aa24bf36ad5bb5d36da7b
Author: liuhongt <hongtao.liu@intel.com>
Date:   Mon Sep 7 15:23:39 2020 +0800

    Adjust testcase.
    
    gcc/testsuite/ChangeLog:
    
            * gcc.target/i386/pr92658-avx512bw-trunc.c: Add
            -mprefer-vector-width=512 to avoid impact of different default
            tune which gcc is built with.

Diff:
---
 gcc/testsuite/gcc.target/i386/pr92658-avx512bw-trunc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/gcc/testsuite/gcc.target/i386/pr92658-avx512bw-trunc.c b/gcc/testsuite/gcc.target/i386/pr92658-avx512bw-trunc.c
index 1f5ea63b08a..c1982f91383 100644
--- a/gcc/testsuite/gcc.target/i386/pr92658-avx512bw-trunc.c
+++ b/gcc/testsuite/gcc.target/i386/pr92658-avx512bw-trunc.c
@@ -1,6 +1,6 @@
 /* PR target/92658 */
 /* { dg-do compile } */
-/* { dg-options "-O2 -ftree-vectorize -mavx512bw -mavx512vl" } */
+/* { dg-options "-O2 -ftree-vectorize -mavx512bw -mavx512vl -mprefer-vector-width=512" } */
 
 typedef unsigned char v8qi __attribute__((vector_size (8)));
 typedef unsigned char v16qi __attribute__((vector_size (16)));