commit 3497f1646f603c396248451c6df8f9d979060351
author Paolo Bonzini <pbonzini@redhat.com> Mon Oct 23 08:52:36 2023 +0200
committer Paolo Bonzini <pbonzini@redhat.com> Fri Dec 29 22:03:59 2023 +0100
tree fb58abd09a997563b369ea6bb6db92180741ad8b
parent 9a5922d6bdc3e047fbe52178104f9b06604f901a

target/i386: prepare for implementation of STOS/SCAS in new decoder

Do not use gen_op, and pull the load from the accumulator into
disas_insn.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

target/i386/tcg/translate.c

diff --git a/target/i386/tcg/translate.c b/target/i386/tcg/translate.c
index e5f7117..ecbd80a 100644
--- a/target/i386/tcg/translate.c
+++ b/target/i386/tcg/translate.c
@@ -1264,7 +1264,6 @@
 
 static void gen_stos(DisasContext *s, MemOp ot)
 {
-    gen_op_mov_v_reg(s, MO_32, s->T0, R_EAX);
     gen_string_movl_A0_EDI(s);
     gen_op_st_v(s, ot, s->T0, s->A0);
     gen_op_add_reg(s, s->aflag, R_EDI, gen_compute_Dshift(s, ot));
@@ -1282,7 +1281,11 @@
 {
     gen_string_movl_A0_EDI(s);
     gen_op_ld_v(s, ot, s->T1, s->A0);
-    gen_op(s, OP_CMPL, ot, R_EAX);
+    tcg_gen_mov_tl(cpu_cc_src, s->T1);
+    tcg_gen_mov_tl(s->cc_srcT, s->T0);
+    tcg_gen_sub_tl(cpu_cc_dst, s->T0, s->T1);
+    set_cc_op(s, CC_OP_SUBB + ot);
+
     gen_op_add_reg(s, s->aflag, R_EDI, gen_compute_Dshift(s, ot));
 }
 
@@ -4952,6 +4955,7 @@
     case 0xaa: /* stosS */
     case 0xab:
         ot = mo_b_d(b, dflag);
+        gen_op_mov_v_reg(s, MO_32, s->T0, R_EAX);
         if (prefixes & (PREFIX_REPZ | PREFIX_REPNZ)) {
             gen_repz_stos(s, ot);
         } else {
@@ -4970,6 +4974,7 @@
     case 0xae: /* scasS */
     case 0xaf:
         ot = mo_b_d(b, dflag);
+        gen_op_mov_v_reg(s, MO_32, s->T0, R_EAX);
         if (prefixes & PREFIX_REPNZ) {
             gen_repz_scas(s, ot, 1);
         } else if (prefixes & PREFIX_REPZ) {