diff --git a/target/i386/tcg/translate.c b/target/i386/tcg/translate.c
index ef0ba822e1..2282c3598c 100644
--- a/target/i386/tcg/translate.c
+++ b/target/i386/tcg/translate.c
@@ -674,13 +674,10 @@ static void gen_helper_out_func(MemOp ot, TCGv_i32 v, TCGv_i32 n)
     }
 }
 
-static void gen_check_io(DisasContext *s, MemOp ot, target_ulong cur_eip,
-                         uint32_t svm_flags)
+static bool gen_check_io(DisasContext *s, MemOp ot, uint32_t svm_flags)
 {
-    target_ulong next_eip;
-
+    tcg_gen_trunc_tl_i32(s->tmp2_i32, s->T0);
     if (PE(s) && (CPL(s) > IOPL(s) || VM86(s))) {
-        tcg_gen_trunc_tl_i32(s->tmp2_i32, s->T0);
         switch (ot) {
         case MO_8:
             gen_helper_check_iob(cpu_env, s->tmp2_i32);
@@ -696,15 +693,20 @@ static void gen_check_io(DisasContext *s, MemOp ot, target_ulong cur_eip,
         }
     }
     if (GUEST(s)) {
+        target_ulong cur_eip = s->base.pc_next - s->cs_base;
+        target_ulong next_eip = s->pc - s->cs_base;
+
         gen_update_cc_op(s);
         gen_jmp_im(s, cur_eip);
-        svm_flags |= (1 << (4 + ot));
-        next_eip = s->pc - s->cs_base;
-        tcg_gen_trunc_tl_i32(s->tmp2_i32, s->T0);
+        if (s->prefix & (PREFIX_REPZ | PREFIX_REPNZ)) {
+            svm_flags |= SVM_IOIO_REP_MASK;
+        }
+        svm_flags |= 1 << (SVM_IOIO_SIZE_SHIFT + ot);
         gen_helper_svm_check_io(cpu_env, s->tmp2_i32,
-                                tcg_const_i32(svm_flags),
-                                tcg_const_i32(next_eip - cur_eip));
+                                tcg_constant_i32(svm_flags),
+                                tcg_constant_i32(next_eip - cur_eip));
     }
+    return true;
 }
 
 static inline void gen_movs(DisasContext *s, MemOp ot)
@@ -2425,11 +2427,6 @@ static void gen_movl_seg_T0(DisasContext *s, X86Seg seg_reg)
     }
 }
 
-static inline int svm_is_rep(int prefixes)
-{
-    return ((prefixes & (PREFIX_REPZ | PREFIX_REPNZ)) ? 8 : 0);
-}
-
 static void gen_svm_check_intercept(DisasContext *s, uint32_t type)
 {
     /* no SVM activated; fast case */
@@ -6483,8 +6480,9 @@ static target_ulong disas_insn(DisasContext *s, CPUState *cpu)
     case 0x6d:
         ot = mo_b_d32(b, dflag);
         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 (!gen_check_io(s, ot, SVM_IOIO_TYPE_MASK | SVM_IOIO_STR_MASK)) {
+            break;
+        }
         if (tb_cflags(s->base.tb) & CF_USE_ICOUNT) {
             gen_io_start();
         }
@@ -6502,8 +6500,9 @@ static target_ulong disas_insn(DisasContext *s, CPUState *cpu)
     case 0x6f:
         ot = mo_b_d32(b, dflag);
         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 (!gen_check_io(s, ot, SVM_IOIO_STR_MASK)) {
+            break;
+        }
         if (tb_cflags(s->base.tb) & CF_USE_ICOUNT) {
             gen_io_start();
         }
@@ -6526,8 +6525,9 @@ static target_ulong disas_insn(DisasContext *s, CPUState *cpu)
         ot = mo_b_d32(b, dflag);
         val = x86_ldub_code(env, s);
         tcg_gen_movi_tl(s->T0, val);
-        gen_check_io(s, ot, pc_start - s->cs_base,
-                     SVM_IOIO_TYPE_MASK | svm_is_rep(prefixes));
+        if (!gen_check_io(s, ot, SVM_IOIO_TYPE_MASK)) {
+            break;
+        }
         if (tb_cflags(s->base.tb) & CF_USE_ICOUNT) {
             gen_io_start();
         }
@@ -6544,8 +6544,9 @@ static target_ulong disas_insn(DisasContext *s, CPUState *cpu)
         ot = mo_b_d32(b, dflag);
         val = x86_ldub_code(env, s);
         tcg_gen_movi_tl(s->T0, val);
-        gen_check_io(s, ot, pc_start - s->cs_base,
-                     svm_is_rep(prefixes));
+        if (!gen_check_io(s, ot, 0)) {
+            break;
+        }
         gen_op_mov_v_reg(s, ot, s->T1, R_EAX);
 
         if (tb_cflags(s->base.tb) & CF_USE_ICOUNT) {
@@ -6563,8 +6564,9 @@ static target_ulong disas_insn(DisasContext *s, CPUState *cpu)
     case 0xed:
         ot = mo_b_d32(b, dflag);
         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));
+        if (!gen_check_io(s, ot, SVM_IOIO_TYPE_MASK)) {
+            break;
+        }
         if (tb_cflags(s->base.tb) & CF_USE_ICOUNT) {
             gen_io_start();
         }
@@ -6580,8 +6582,9 @@ static target_ulong disas_insn(DisasContext *s, CPUState *cpu)
     case 0xef:
         ot = mo_b_d32(b, dflag);
         tcg_gen_ext16u_tl(s->T0, cpu_regs[R_EDX]);
-        gen_check_io(s, ot, pc_start - s->cs_base,
-                     svm_is_rep(prefixes));
+        if (!gen_check_io(s, ot, 0)) {
+            break;
+        }
         gen_op_mov_v_reg(s, ot, s->T1, R_EAX);
 
         if (tb_cflags(s->base.tb) & CF_USE_ICOUNT) {
