diff --git a/qemu/accel/tcg/cpu-exec.c b/qemu/accel/tcg/cpu-exec.c
index a9986d16..99c313de 100644
--- a/qemu/accel/tcg/cpu-exec.c
+++ b/qemu/accel/tcg/cpu-exec.c
@@ -466,27 +466,32 @@ static inline void cpu_loop_exec_tb(CPUState *cpu, TranslationBlock *tb,
     }
 }
 
-static void cpu_exec_step(struct uc_struct *uc, CPUState *cpu)
+void cpu_exec_step_atomic(struct uc_struct *uc, CPUState *cpu)
 {
     CPUArchState *env = (CPUArchState *)cpu->env_ptr;
     TranslationBlock *tb;
     target_ulong cs_base, pc;
     uint32_t flags;
     uint32_t cflags = 1 | CF_IGNORE_ICOUNT;
+    uint32_t cf_mask = cflags & CF_HASH_MASK;
 
     cpu_get_tb_cpu_state(env, &pc, &cs_base, &flags);
 
     if (sigsetjmp(cpu->jmp_env, 0) == 0) {
-        tb = tb_lookup__cpu_state(cpu, &pc, &cs_base, &flags,
-                                  cflags & CF_HASH_MASK);
+        tb = tb_lookup__cpu_state(cpu, &pc, &cs_base, &flags, cf_mask);
         if (tb == NULL) {
             mmap_lock();
-            tb = tb_gen_code(cpu, pc, cs_base, flags, cflags);
+            tb = tb_htable_lookup(cpu, pc, cs_base, flags, cf_mask);
+            if (likely(tb == NULL)) {
+                tb = tb_gen_code(cpu, pc, cs_base, flags, cflags);
+            }
             mmap_unlock();
         }
 
+        uc->parallel_cpus = false;
         /* execute the generated code */
         cpu_tb_exec(cpu, tb);
+        uc->parallel_cpus = true;
     } else {
         /* We may have exited due to another problem here, so we need
          * to reset any tb_locks we may have taken but didn't release.
@@ -502,20 +507,6 @@ static void cpu_exec_step(struct uc_struct *uc, CPUState *cpu)
     }
 }
 
-void cpu_exec_step_atomic(struct uc_struct *uc, CPUState *cpu)
-{
-    // Unicorn: commented out
-    //start_exclusive();
-
-    /* Since we got here, we know that parallel_cpus must be true.  */
-    uc->parallel_cpus = false;
-    cpu_exec_step(uc, cpu);
-    uc->parallel_cpus = true;
-
-    // Unicorn: commented out
-    //end_exclusive();
-}
-
 /* main execution loop */
 
 int cpu_exec(struct uc_struct *uc, CPUState *cpu)