diff mbox

[v5,08/19] target/arm: optimize cross-page direct jumps in softmmu

Message ID 20170427120006.20564-9-rth@twiddle.net (mailing list archive)
State New, archived
Headers show

Commit Message

Richard Henderson April 27, 2017, 11:59 a.m. UTC
From: "Emilio G. Cota" <cota@braap.org>

Instead of unconditionally exiting to the exec loop, use the
lookup_and_goto_ptr helper to jump to the target if it is valid.

Perf impact: see next commit's log.

Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <1493263764-18657-7-git-send-email-cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
---
 target/arm/translate.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

Comments

Alex Bennée April 28, 2017, 11:30 a.m. UTC | #1
Richard Henderson <rth@twiddle.net> writes:

> From: "Emilio G. Cota" <cota@braap.org>
>
> Instead of unconditionally exiting to the exec loop, use the
> lookup_and_goto_ptr helper to jump to the target if it is valid.
>
> Perf impact: see next commit's log.
>
> Reviewed-by: Richard Henderson <rth@twiddle.net>
> Signed-off-by: Emilio G. Cota <cota@braap.org>
> Message-Id: <1493263764-18657-7-git-send-email-cota@braap.org>
> Signed-off-by: Richard Henderson <rth@twiddle.net>

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>

> ---
>  target/arm/translate.c | 6 +++++-
>  1 file changed, 5 insertions(+), 1 deletion(-)
>
> diff --git a/target/arm/translate.c b/target/arm/translate.c
> index 0b5a0bc..facb52f 100644
> --- a/target/arm/translate.c
> +++ b/target/arm/translate.c
> @@ -4153,8 +4153,12 @@ static inline void gen_goto_tb(DisasContext *s, int n, target_ulong dest)
>          gen_set_pc_im(s, dest);
>          tcg_gen_exit_tb((uintptr_t)s->tb + n);
>      } else {
> +        TCGv addr = tcg_temp_new();
> +
>          gen_set_pc_im(s, dest);
> -        tcg_gen_exit_tb(0);
> +        tcg_gen_extu_i32_tl(addr, cpu_R[15]);
> +        tcg_gen_lookup_and_goto_ptr(addr);
> +        tcg_temp_free(addr);
>      }
>  }


--
Alex Bennée
diff mbox

Patch

diff --git a/target/arm/translate.c b/target/arm/translate.c
index 0b5a0bc..facb52f 100644
--- a/target/arm/translate.c
+++ b/target/arm/translate.c
@@ -4153,8 +4153,12 @@  static inline void gen_goto_tb(DisasContext *s, int n, target_ulong dest)
         gen_set_pc_im(s, dest);
         tcg_gen_exit_tb((uintptr_t)s->tb + n);
     } else {
+        TCGv addr = tcg_temp_new();
+
         gen_set_pc_im(s, dest);
-        tcg_gen_exit_tb(0);
+        tcg_gen_extu_i32_tl(addr, cpu_R[15]);
+        tcg_gen_lookup_and_goto_ptr(addr);
+        tcg_temp_free(addr);
     }
 }