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[176.184.10.225]) by smtp.gmail.com with ESMTPSA id k25-20020a7bc419000000b003f96d10eafbsm4143467wmi.12.2023.06.19.07.23.40 for (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 19 Jun 2023 07:23:41 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1687184621; x=1689776621; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:to:from:from:to:cc:subject:date:message-id :reply-to; bh=pwqG4bOndCwR7WWKOm2/D1bdEjIJvQWtHJFzguX9raY=; b=wgMAUfaq3czt70PcOIIf0zuUDTpaGVvWHb2rTR92yNK5umgGeahY2ube/nakNCj+kF B1RyNPF1T+o3xvxGJwJv4XPuDSqtNtjFXL8HC+cbS8mqHFehzUYBmYGPy1IQkJFiRFDO zg4eWXCXG6Apa+GxWfT+D7p8ukViSSCxt/kCzz+wjYPX2JOCuZ0BOex6JS4YrGa9C4bw 3i5sze2VlCm0EhBgkxGHARd9c6OY4+9wotF9bt1tgQ+1x7P6fAI+ESp9kOT4zwUb9V6F h8cUUaH+yWASvGUvwAnGUiLRNyql18DPjwGDcy/SJoEADXQhE9cTLe9BRLx/4FsWlnJt 7GJg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1687184621; x=1689776621; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=pwqG4bOndCwR7WWKOm2/D1bdEjIJvQWtHJFzguX9raY=; b=QR3sAgIhnWflHl5QqP/ZP58jm3MSFsvm66Ucq5DwvqiLvldOGb4Ushinbei5PCaPmf Z0SD0mv8ePrrN8QGIEu/0zcWKEh+AvYKHfhh1hytqUwaSEv31NqGVqNqK/gcAQcUPkBP it7bp1OtR3af+UsVyfi/94CVZEGo2L8+pu+ywTGqpoM61lO7fBVmMdcX8qRM3i698USo NLFISAUznlp6fWzbZkANQCBOz6DmtqQLLT59e9l6p+ygBeB2IszmHRiHYlwgvh4yp1Ya mJzfODDBX7wLDbVLo/SFyNEkVjEijkKbb0oj7Y5d72MLoR6brMlewyFBRUtlE2HKGCAT +T9Q== X-Gm-Message-State: AC+VfDwFGeHovCorN5EybXviWEtjO1/tg5Gd+Cj4O5qP8fPKO2Sg5Iz/ ZxvhTG6AuymE4pcwIlPSEMyQqBx9C98Z0RP0+3HPFkMu X-Google-Smtp-Source: ACHHUZ5pQxmA4WgBd/NCYWPaCU2GSB8nFxtW1Xk2qvcNgIl+omyqQUSAi8KORW1LZ8gMApUrzaexSw== X-Received: by 2002:a05:600c:3799:b0:3f9:b540:862d with SMTP id o25-20020a05600c379900b003f9b540862dmr278293wmr.28.1687184621344; Mon, 19 Jun 2023 07:23:41 -0700 (PDT) From: Richard Henderson To: qemu-devel@nongnu.org Subject: [PATCH v3 3/5] tcg: Elide memory barriers implied by the host memory model Date: Mon, 19 Jun 2023 16:23:31 +0200 Message-Id: <20230619142333.429028-4-richard.henderson@linaro.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230619142333.429028-1-richard.henderson@linaro.org> References: <20230619142333.429028-1-richard.henderson@linaro.org> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=2a00:1450:4864:20::335; envelope-from=richard.henderson@linaro.org; helo=mail-wm1-x335.google.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: qemu-devel-bounces+importer=patchew.org@nongnu.org X-ZohoMail-DKIM: pass (identity @linaro.org) X-ZM-MESSAGEID: 1687184674557100002 Content-Type: text/plain; charset="utf-8" Reduce the set of required barriers to those needed by the host right from the beginning. Signed-off-by: Richard Henderson --- tcg/tcg-op.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/tcg/tcg-op.c b/tcg/tcg-op.c index 7aadb37756..574001c221 100644 --- a/tcg/tcg-op.c +++ b/tcg/tcg-op.c @@ -115,7 +115,11 @@ void tcg_gen_mb(TCGBar mb_type) #endif =20 if (parallel) { - tcg_gen_op1(INDEX_op_mb, mb_type); + /* We can elide anything which the host provides for free. */ + mb_type &=3D ~TCG_TARGET_DEFAULT_MO; + if (mb_type & TCG_MO_ALL) { + tcg_gen_op1(INDEX_op_mb, mb_type); + } } } =20 --=20 2.34.1