[for-4.1,24/24] icount: clean up cpu_can_io before jumping to the next block

Commit Message

Pavel Dovgalyuk June 21, 2019, 8:22 a.m. UTC

From: Pavel Dovgalyuk <[e-mail]>

Most of IO instructions can be executed only at the end of the block in
icount mode. Therefore translator can set cpu_can_io flag when translating
the last instruction.
But when the blocks are chained, then this flag is not reset and may
remain set at the beginning of the next block.
This patch resets the flag before "chaining" the translation blocks.

Signed-off-by: Pavel Dovgalyuk <[e-mail]>
---
 accel/tcg/tcg-runtime.c |    2 ++
 1 file changed, 2 insertions(+)

Patch

diff --git a/accel/tcg/tcg-runtime.c b/accel/tcg/tcg-runtime.c
index 8a1e408e31..fe6b83d0fc 100644
--- a/accel/tcg/tcg-runtime.c
+++ b/accel/tcg/tcg-runtime.c
@@ -151,6 +151,8 @@  void *HELPER(lookup_tb_ptr)(CPUArchState *env)
     target_ulong cs_base, pc;
     uint32_t flags;
 
+    /* We are going to jump to the next block. can_do_io should be reset */
+    cpu->can_do_io = !use_icount;
     tb = tb_lookup__cpu_state(cpu, &pc, &cs_base, &flags, curr_cflags());
     if (tb == NULL) {
         return tcg_ctx->code_gen_epilogue;