[PATCH] target-i386: remove gen_io_end

[PATCH] target-i386: remove gen_io_end

[Paolo Bonzini]

Force the end of a translation block after an I/O instruction in
icount mode.  For consistency, all CF_USE_ICOUNT code is kept in
disas_insn instead of having it in gen_ins and gen_outs.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 target/i386/translate.c | 22 +++++++++-------------
 1 file changed, 9 insertions(+), 13 deletions(-)

diff --git a/target/i386/translate.c b/target/i386/translate.c
index 5e5dbb41b0..4d808a6f93 100644
--- a/target/i386/translate.c
+++ b/target/i386/translate.c
@@ -1128,9 +1128,6 @@ static void gen_bpt_io(DisasContext *s, TCGv_i32 t_port, int ot)
 
 static inline void gen_ins(DisasContext *s, MemOp ot)
 {
-    if (tb_cflags(s->base.tb) & CF_USE_ICOUNT) {
-        gen_io_start();
-    }
     gen_string_movl_A0_EDI(s);
     /* Note: we must do this dummy write first to be restartable in
        case of page fault. */
@@ -1143,16 +1140,10 @@ static inline void gen_ins(DisasContext *s, MemOp ot)
     gen_op_movl_T0_Dshift(s, ot);
     gen_op_add_reg_T0(s, s->aflag, R_EDI);
     gen_bpt_io(s, s->tmp2_i32, ot);
-    if (tb_cflags(s->base.tb) & CF_USE_ICOUNT) {
-        gen_io_end();
-    }
 }
 
 static inline void gen_outs(DisasContext *s, MemOp ot)
 {
-    if (tb_cflags(s->base.tb) & CF_USE_ICOUNT) {
-        gen_io_start();
-    }
     gen_string_movl_A0_ESI(s);
     gen_op_ld_v(s, ot, s->T0, s->A0);
 
@@ -1163,9 +1154,6 @@ static inline void gen_outs(DisasContext *s, MemOp ot)
     gen_op_movl_T0_Dshift(s, ot);
     gen_op_add_reg_T0(s, s->aflag, R_ESI);
     gen_bpt_io(s, s->tmp2_i32, ot);
-    if (tb_cflags(s->base.tb) & CF_USE_ICOUNT) {
-        gen_io_end();
-    }
 }
 
 /* same method as Valgrind : we generate jumps to current or next
@@ -6400,8 +6388,12 @@ static target_ulong disas_insn(DisasContext *s, CPUState *cpu)
         tcg_gen_ext16u_tl(s->T0, cpu_regs[R_EDX]);
         gen_check_io(s, ot, pc_start - s->cs_base, 
                      SVM_IOIO_TYPE_MASK | svm_is_rep(prefixes) | 4);
+        if (tb_cflags(s->base.tb) & CF_USE_ICOUNT) {
+            gen_io_start();
+        }
         if (prefixes & (PREFIX_REPZ | PREFIX_REPNZ)) {
             gen_repz_ins(s, ot, pc_start - s->cs_base, s->pc - s->cs_base);
+            /* jump generated by gen_repz_ins */
         } else {
             gen_ins(s, ot);
             if (tb_cflags(s->base.tb) & CF_USE_ICOUNT) {
@@ -6415,8 +6407,12 @@ static target_ulong disas_insn(DisasContext *s, CPUState *cpu)
         tcg_gen_ext16u_tl(s->T0, cpu_regs[R_EDX]);
         gen_check_io(s, ot, pc_start - s->cs_base,
                      svm_is_rep(prefixes) | 4);
+        if (tb_cflags(s->base.tb) & CF_USE_ICOUNT) {
+            gen_io_start();
+        }
         if (prefixes & (PREFIX_REPZ | PREFIX_REPNZ)) {
             gen_repz_outs(s, ot, pc_start - s->cs_base, s->pc - s->cs_base);
+            /* jump generated by gen_repz_outs */
         } else {
             gen_outs(s, ot);
             if (tb_cflags(s->base.tb) & CF_USE_ICOUNT) {
@@ -8039,7 +8035,7 @@ static target_ulong disas_insn(DisasContext *s, CPUState *cpu)
                     gen_helper_read_crN(s->T0, cpu_env, tcg_const_i32(reg));
                     gen_op_mov_reg_v(s, ot, rm, s->T0);
                     if (tb_cflags(s->base.tb) & CF_USE_ICOUNT) {
-                        gen_io_end();
+                        gen_jmp(s, s->pc - s->cs_base);
                     }
                 }
                 break;
-- 
2.26.2

Re: [PATCH] target-i386: remove gen_io_end

[Richard Henderson]

On 6/26/20 3:44 AM, Paolo Bonzini wrote:
> Force the end of a translation block after an I/O instruction in
> icount mode.  For consistency, all CF_USE_ICOUNT code is kept in
> disas_insn instead of having it in gen_ins and gen_outs.
> 
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> ---
>  target/i386/translate.c | 22 +++++++++-------------
>  1 file changed, 9 insertions(+), 13 deletions(-)

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

r~