exec: drop cpu_can_do_io, just read cpu->can_do_io

After commit 626cf8f (icount: set can_do_io outside TB execution,
2014-12-08), can_do_io is set to 1 if not executing code.  It is
no longer necessary to make this assumption in cpu_can_do_io.

It is also possible to remove the use_icount test, simply by
never setting cpu->can_do_io to 0 unless use_icount is true.

With these changes cpu_can_do_io boils down to a read of
cpu->can_do_io.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/cpu-exec.c b/cpu-exec.c
index 407fa47..713540f 100644
--- a/cpu-exec.c
+++ b/cpu-exec.c
@@ -196,7 +196,7 @@ static inline tcg_target_ulong cpu_tb_exec(CPUState *cpu, uint8_t *tb_ptr)
     }
 #endif /* DEBUG_DISAS */
 
-    cpu->can_do_io = 0;
+    cpu->can_do_io = !use_icount;
     next_tb = tcg_qemu_tb_exec(env, tb_ptr);
     cpu->can_do_io = 1;
     trace_exec_tb_exit((void *) (next_tb & ~TB_EXIT_MASK),