target/i386: no single-step exception after MOV or POP SS

Intel SDM 18.3.1.4 "If an occurrence of the MOV or POP instruction
loads the SS register executes with EFLAGS.TF = 1, no single-step debug
exception occurs following the MOV or POP instruction."

Cc: qemu-stable@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/target/i386/tcg/translate.c b/target/i386/tcg/translate.c
index ebcff8766cf101ce4d3f123cffa4d31ab2c123db..9782250b20b935b861c6d76b6fe27b5c2d0dd469 100644 (file)
--- a/target/i386/tcg/translate.c
+++ b/target/i386/tcg/translate.c
@@ -2273,7 +2273,7 @@ gen_eob_worker(DisasContext *s, bool inhibit, bool recheck_tf, bool jr)
     if (recheck_tf) {
         gen_helper_rechecking_single_step(tcg_env);
         tcg_gen_exit_tb(NULL, 0);
-    } else if (s->flags & HF_TF_MASK) {
+    } else if ((s->flags & HF_TF_MASK) && !inhibit) {
         gen_helper_single_step(tcg_env);
     } else if (jr &&
                /* give irqs a chance to happen */