[PULL,04/24] target/i386: cleanup eob handling of RSM

Commit Message

Paolo Bonzini May 25, 2024, 11:33 a.m. UTC

gen_helper_rsm cannot generate an exception, and reloads the flags.
So there's no need to spill cc_op and update cpu_eip, but on the
other hand cc_op must be reset to CC_OP_EFLAGS before returning.

It all works by chance, because by spilling cc_op before the call
to the helper, it becomes non-dirty and gen_eob will not overwrite
the CC_OP_EFLAGS value that is placed there by the helper.  But
let's clean it up.

Reviewed-by: Richard Henderson <[e-mail]>
Signed-off-by: Paolo Bonzini <[e-mail]>
---
 target/i386/tcg/translate.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

Patch

diff --git a/target/i386/tcg/translate.c b/target/i386/tcg/translate.c
index 9782250b20b..849864d1aa2 100644
--- a/target/i386/tcg/translate.c
+++ b/target/i386/tcg/translate.c
@@ -4488,9 +4488,8 @@  static void disas_insn_old(DisasContext *s, CPUState *cpu, int b)
         /* we should not be in SMM mode */
         g_assert_not_reached();
 #else
-        gen_update_cc_op(s);
-        gen_update_eip_next(s);
         gen_helper_rsm(tcg_env);
+        set_cc_op(s, CC_OP_EFLAGS);
 #endif /* CONFIG_USER_ONLY */
         s->base.is_jmp = DISAS_EOB_ONLY;
         break;