@@ -1803,16 +1803,19 @@ static void disas_insn_new(DisasContext *s,
CPUState *cpu, int b)
}
break;
- case X86_SPECIAL_MMX:
- if (!(s->prefix & (PREFIX_REPZ | PREFIX_REPNZ | PREFIX_DATA))) {
- gen_helper_enter_mmx(cpu_env);
- }
+ default:
break;
}
if (!validate_vex(s, &decode)) {
return;
}
+
+ if (decode.e.special == X86_SPECIAL_MMX &&
+ !(s->prefix & (PREFIX_REPZ | PREFIX_REPNZ | PREFIX_DATA))) {
+ gen_helper_enter_mmx(cpu_env);
+ }
+
if (decode.op[0].has_ea || decode.op[1].has_ea || decode.op[2].has_ea) {
gen_load_ea(s, &decode.mem, decode.e.vex_class == 12);
When CR0.TS=1, execution of x87 FPU, MMX, and some SSE instructions will cause a Device Not Available (DNA) exception (#NM). System software uses this exception event to lazily context switch FPU state. Before this patch, enter_mmx helpers may be generated just before #NM generation, prematurely resetting FPU state before the guest has a chance to save it. Signed-off-by: Matt Borgerson <contact@mborgerson.com> --- target/i386/tcg/decode-new.c.inc | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) }