From: Richard Henderson <richard.henderson@linaro.org>
To: qemu-devel@nongnu.org
Cc: peter.maydell@linaro.org, Richard Henderson <rth@twiddle.net>
Subject: [PULL 4/8] tcg/arm: Expand epilogue inline
Date: Fri, 28 Feb 2020 18:43:43 -0800 [thread overview]
Message-ID: <20200229024347.22826-5-richard.henderson@linaro.org> (raw)
In-Reply-To: <20200229024347.22826-1-richard.henderson@linaro.org>
From: Richard Henderson <rth@twiddle.net>
It is, after all, just two instructions.
Profiling on a cortex-a15, using -d nochain to increase the number
of exit_tb that are executed, shows a minor improvement of 0.5%.
Signed-off-by: Richard Henderson <rth@twiddle.net>
---
tcg/arm/tcg-target.inc.c | 12 ++----------
1 file changed, 2 insertions(+), 10 deletions(-)
diff --git a/tcg/arm/tcg-target.inc.c b/tcg/arm/tcg-target.inc.c
index e1aa740ba4..6aa7757aac 100644
--- a/tcg/arm/tcg-target.inc.c
+++ b/tcg/arm/tcg-target.inc.c
@@ -1745,7 +1745,6 @@ static void tcg_out_qemu_st(TCGContext *s, const TCGArg *args, bool is64)
#endif
}
-static tcg_insn_unit *tb_ret_addr;
static void tcg_out_epilogue(TCGContext *s);
static inline void tcg_out_op(TCGContext *s, TCGOpcode opc,
@@ -1756,14 +1755,8 @@ static inline void tcg_out_op(TCGContext *s, TCGOpcode opc,
switch (opc) {
case INDEX_op_exit_tb:
- /* Reuse the zeroing that exists for goto_ptr. */
- a0 = args[0];
- if (a0 == 0) {
- tcg_out_goto(s, COND_AL, s->code_gen_epilogue);
- } else {
- tcg_out_movi32(s, COND_AL, TCG_REG_R0, args[0]);
- tcg_out_goto(s, COND_AL, tb_ret_addr);
- }
+ tcg_out_movi(s, TCG_TYPE_PTR, TCG_REG_R0, args[0]);
+ tcg_out_epilogue(s);
break;
case INDEX_op_goto_tb:
{
@@ -2309,7 +2302,6 @@ static void tcg_target_qemu_prologue(TCGContext *s)
*/
s->code_gen_epilogue = s->code_ptr;
tcg_out_movi(s, TCG_TYPE_PTR, TCG_REG_R0, 0);
- tb_ret_addr = s->code_ptr;
tcg_out_epilogue(s);
}
--
2.20.1
next prev parent reply other threads:[~2020-02-29 2:48 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-02-29 2:43 [PULL 0/8] tcg patch queue Richard Henderson
2020-02-29 2:43 ` [PULL 1/8] accel/tcg: fix race in cpu_exec_step_atomic (bug 1863025) Richard Henderson
2020-02-29 2:43 ` [PULL 2/8] compiler.h: Don't use compile-time assert when __NO_INLINE__ is defined Richard Henderson
2020-02-29 2:43 ` [PULL 3/8] tcg/arm: Split out tcg_out_epilogue Richard Henderson
2020-02-29 2:43 ` Richard Henderson [this message]
2020-02-29 2:43 ` [PULL 5/8] accel/tcg: use units.h for defining code gen buffer sizes Richard Henderson
2020-02-29 2:43 ` [PULL 6/8] accel/tcg: remove link between guest ram and TCG cache size Richard Henderson
2020-02-29 2:43 ` [PULL 7/8] accel/tcg: only USE_STATIC_CODE_GEN_BUFFER on 32 bit hosts Richard Henderson
2020-02-29 2:43 ` [PULL 8/8] accel/tcg: increase default code gen buffer size for 64 bit Richard Henderson
2020-03-02 13:00 ` [PULL 0/8] tcg patch queue Peter Maydell
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=20200229024347.22826-5-richard.henderson@linaro.org \
--to=richard.henderson@linaro.org \
--cc=peter.maydell@linaro.org \
--cc=qemu-devel@nongnu.org \
--cc=rth@twiddle.net \
/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).