[PATCH] x86emul: correct {evex} assembler capability check

[Jan Beulich <jbeulich@xxxxxxxx>]

The {evex} pseudo prefix gets rejected by gas for insns not allowing
EVEX encoding. Except there's a gas bug due to which its check gets
bypassed for insns without operands. Let's not rely on that bug to
remain there.

Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>

--- a/tools/tests/x86_emulator/Makefile
+++ b/tools/tests/x86_emulator/Makefile
@@ -112,7 +112,7 @@ $(foreach flavor,$(SIMD) $(FMA),$(eval $
 
 # Also explicitly check for {evex} pseudo-prefix support, which got introduced
 # only after AVX512F and some of its extensions.
-TARGET-$(shell echo 'asm("{evex} vzeroall");' | $(CC) -x c -c -o /dev/null - 
|| echo y) :=
+TARGET-$(shell echo 'asm("{evex} vmovaps %xmm0$(comma)%xmm0");' | $(CC) -x c 
-c -o /dev/null - || echo y) :=
 
 ifeq ($(TARGET-y),)
 $(warning Test harness not built, use newer compiler than "$(CC)" (version 
$(shell $(CC) -dumpversion)) and an "{evex}" capable assembler)