From: Nicholas Piggin <npiggin@gmail.com>
To: Daniel Henrique Barboza <danielhb413@gmail.com>
Cc: Nicholas Piggin <npiggin@gmail.com>,
Richard Henderson <richard.henderson@linaro.org>,
qemu-ppc@nongnu.org, qemu-devel@nongnu.org,
qemu-stable@nongnu.org
Subject: [PATCH 3/4] target/ppc: Remove larx/stcx. memory barrier semantics
Date: Sun, 4 Jun 2023 20:28:56 +1000 [thread overview]
Message-ID: <20230604102858.148584-3-npiggin@gmail.com> (raw)
In-Reply-To: <20230604102858.148584-1-npiggin@gmail.com>
larx and stcx. are not defined to order any memory operations.
Remove the barriers.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
target/ppc/translate.c | 11 -----------
1 file changed, 11 deletions(-)
diff --git a/target/ppc/translate.c b/target/ppc/translate.c
index 5195047146..77e1c5abb6 100644
--- a/target/ppc/translate.c
+++ b/target/ppc/translate.c
@@ -3591,7 +3591,6 @@ static void gen_load_locked(DisasContext *ctx, MemOp memop)
tcg_gen_movi_tl(cpu_reserve_size, memop_size(memop));
tcg_gen_qemu_ld_tl(gpr, t0, ctx->mem_idx, memop | MO_ALIGN);
tcg_gen_mov_tl(cpu_reserve_val, gpr);
- tcg_gen_mb(TCG_MO_ALL | TCG_BAR_LDAQ);
}
#define LARX(name, memop) \
@@ -3835,11 +3834,6 @@ static void gen_conditional_store(DisasContext *ctx, MemOp memop)
gen_set_label(l1);
- /*
- * Address mismatch implies failure. But we still need to provide
- * the memory barrier semantics of the instruction.
- */
- tcg_gen_mb(TCG_MO_ALL | TCG_BAR_STRL);
tcg_gen_trunc_tl_i32(cpu_crf[0], cpu_so);
gen_set_label(l2);
@@ -3943,11 +3937,6 @@ static void gen_stqcx_(DisasContext *ctx)
tcg_gen_br(lab_over);
gen_set_label(lab_fail);
- /*
- * Address mismatch implies failure. But we still need to provide
- * the memory barrier semantics of the instruction.
- */
- tcg_gen_mb(TCG_MO_ALL | TCG_BAR_STRL);
tcg_gen_trunc_tl_i32(cpu_crf[0], cpu_so);
gen_set_label(lab_over);
--
2.40.1
next prev parent reply other threads:[~2023-06-04 10:30 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-06-04 10:28 [PATCH 1/4] target/ppc: Fix lqarx to set cpu_reserve Nicholas Piggin
2023-06-04 10:28 ` [PATCH 2/4] target/ppc: Ensure stcx size matches larx Nicholas Piggin
2023-06-04 16:58 ` Richard Henderson
2023-06-05 6:27 ` Nicholas Piggin
2023-06-19 15:48 ` Richard Henderson
2023-06-19 15:55 ` Peter Maydell
2023-06-19 17:02 ` Richard Henderson
2023-06-19 17:14 ` Peter Maydell
2023-06-20 3:39 ` Nicholas Piggin
2023-06-04 10:28 ` Nicholas Piggin [this message]
2023-06-04 16:12 ` [PATCH 3/4] target/ppc: Remove larx/stcx. memory barrier semantics Richard Henderson
2023-06-04 10:28 ` [PATCH 4/4] target/ppc: Rework store conditional to avoid branch Nicholas Piggin
2023-06-04 16:22 ` Richard Henderson
2023-06-04 16:05 ` [PATCH 1/4] target/ppc: Fix lqarx to set cpu_reserve Richard Henderson
2023-06-05 2:33 ` Nicholas Piggin
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=20230604102858.148584-3-npiggin@gmail.com \
--to=npiggin@gmail.com \
--cc=danielhb413@gmail.com \
--cc=qemu-devel@nongnu.org \
--cc=qemu-ppc@nongnu.org \
--cc=qemu-stable@nongnu.org \
--cc=richard.henderson@linaro.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.