qemu-devel.nongnu.org archive mirror
 help / color / mirror / Atom feed
From: Richard Henderson <richard.henderson@linaro.org>
To: qemu-devel@nongnu.org
Cc: "Philippe Mathieu-Daudé" <philmd@linaro.org>
Subject: [PULL 1/6] accel/tcg: Avoid load of icount_decr if unused
Date: Thu, 28 Sep 2023 12:41:51 -0700	[thread overview]
Message-ID: <20230928194156.237351-2-richard.henderson@linaro.org> (raw)
In-Reply-To: <20230928194156.237351-1-richard.henderson@linaro.org>

With CF_NOIRQ and without !CF_USE_ICOUNT, the load isn't used.
Avoid emitting it.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 accel/tcg/translator.c | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/accel/tcg/translator.c b/accel/tcg/translator.c
index 1a6a5448c8..a3983019a5 100644
--- a/accel/tcg/translator.c
+++ b/accel/tcg/translator.c
@@ -49,12 +49,15 @@ bool translator_io_start(DisasContextBase *db)
 
 static TCGOp *gen_tb_start(uint32_t cflags)
 {
-    TCGv_i32 count = tcg_temp_new_i32();
+    TCGv_i32 count = NULL;
     TCGOp *icount_start_insn = NULL;
 
-    tcg_gen_ld_i32(count, cpu_env,
-                   offsetof(ArchCPU, neg.icount_decr.u32) -
-                   offsetof(ArchCPU, env));
+    if ((cflags & CF_USE_ICOUNT) || !(cflags & CF_NOIRQ)) {
+        count = tcg_temp_new_i32();
+        tcg_gen_ld_i32(count, cpu_env,
+                       offsetof(ArchCPU, neg.icount_decr.u32) -
+                       offsetof(ArchCPU, env));
+    }
 
     if (cflags & CF_USE_ICOUNT) {
         /*
-- 
2.34.1



  reply	other threads:[~2023-09-28 19:42 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-09-28 19:41 [PULL 0/6] tcg patch queue Richard Henderson
2023-09-28 19:41 ` Richard Henderson [this message]
2023-09-28 19:41 ` [PULL 2/6] accel/tcg: Hoist CF_MEMI_ONLY check outside translation loop Richard Henderson
2023-09-28 19:41 ` [PULL 3/6] accel/tcg: Track current value of can_do_io in the TB Richard Henderson
2023-09-28 19:41 ` [PULL 4/6] accel/tcg: Improve setting of can_do_io at start of TB Richard Henderson
2023-09-28 19:41 ` [PULL 5/6] accel/tcg: Always set CF_LAST_IO with CF_NOIRQ Richard Henderson
2023-09-28 19:41 ` [PULL 6/6] accel/tcg: Always require can_do_io Richard Henderson
2023-10-02 21:56 ` [PULL 0/6] tcg patch queue Stefan Hajnoczi
2023-10-02 22:46 ` Michael Tokarev
2023-10-03  0:18   ` Richard Henderson

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20230928194156.237351-2-richard.henderson@linaro.org \
    --to=richard.henderson@linaro.org \
    --cc=philmd@linaro.org \
    --cc=qemu-devel@nongnu.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).