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authorPavel Dovgalyuk2019-07-25 10:44:55 +0200
committerPaolo Bonzini2019-08-20 17:26:22 +0200
commit9e9b10c6491153b60ccfd021328f1f88e1669550 (patch)
treefc7d5e3cf568f14e22930b6d055a5a7ef3523c49 /include
parenticount: clean up cpu_can_io at the entry to the block (diff)
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icount: remove unnecessary gen_io_end calls
Prior patch resets can_do_io flag at the TB entry. Therefore there is no need in resetting this flag at the end of the block. This patch removes redundant gen_io_end calls. Signed-off-by: Pavel Dovgalyuk <Pavel.Dovgaluk@ispras.ru> Message-Id: <156404429499.18669.13404064982854123855.stgit@pasha-Precision-3630-Tower> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Pavel Dovgalyuk <pavel.dovgaluk@gmail.com>
Diffstat (limited to 'include')
-rw-r--r--include/exec/gen-icount.h8
1 files changed, 7 insertions, 1 deletions
diff --git a/include/exec/gen-icount.h b/include/exec/gen-icount.h
index 4004e6c9d0..822c43cfd3 100644
--- a/include/exec/gen-icount.h
+++ b/include/exec/gen-icount.h
@@ -16,6 +16,13 @@ static inline void gen_io_start(void)
tcg_temp_free_i32(tmp);
}
+/*
+ * cpu->can_do_io is cleared automatically at the beginning of
+ * each translation block. The cost is minimal and only paid
+ * for -icount, plus it would be very easy to forget doing it
+ * in the translator. Therefore, backends only need to call
+ * gen_io_start.
+ */
static inline void gen_io_end(void)
{
TCGv_i32 tmp = tcg_const_i32(0);
@@ -58,7 +65,6 @@ static inline void gen_tb_start(TranslationBlock *tb)
tcg_gen_st16_i32(count, cpu_env,
offsetof(ArchCPU, neg.icount_decr.u16.low) -
offsetof(ArchCPU, env));
- /* Disable I/O by default */
gen_io_end();
}