From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 08A22C4332F for ; Thu, 20 Oct 2022 14:38:14 +0000 (UTC) Received: from localhost ([::1]:43186 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1olWgW-0006R9-8x for qemu-devel@archiver.kernel.org; Thu, 20 Oct 2022 10:38:12 -0400 Received: from [::1] (helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1olWWP-0007Gk-0Y for qemu-devel@archiver.kernel.org; Thu, 20 Oct 2022 10:27:45 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:56886) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1olTwr-0008E8-JO; Thu, 20 Oct 2022 07:43:06 -0400 Received: from out30-44.freemail.mail.aliyun.com ([115.124.30.44]:55121) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1olTwp-0004Ur-69; Thu, 20 Oct 2022 07:42:53 -0400 X-Alimail-AntiSpam: AC=PASS; BC=-1|-1; BR=01201311R291e4; CH=green; DM=||false|; DS=||; FP=0|-1|-1|-1|0|-1|-1|-1; HT=ay29a033018046059; MF=zhiwei_liu@linux.alibaba.com; NM=1; PH=DS; RN=7; SR=0; TI=SMTPD_---0VSf18.m_1666266159; Received: from 30.221.96.197(mailfrom:zhiwei_liu@linux.alibaba.com fp:SMTPD_---0VSf18.m_1666266159) by smtp.aliyun-inc.com; Thu, 20 Oct 2022 19:42:40 +0800 Message-ID: <6c468fb2-c41e-a7dc-8fef-10185dffeca9@linux.alibaba.com> Date: Thu, 20 Oct 2022 19:42:38 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:102.0) Gecko/20100101 Thunderbird/102.3.3 Subject: Re: [RFC PATCH 1/3] tcg/riscv: Fix base regsiter for qemu_ld/st To: Richard Henderson , qemu-devel@nongnu.org, qemu-riscv@nongnu.org Cc: Alistair.Francis@wdc.com, palmer@dabbelt.com, bin.meng@windriver.com, lzw194868@alibaba-inc.com References: <20221020104154.4276-1-zhiwei_liu@linux.alibaba.com> <20221020104154.4276-2-zhiwei_liu@linux.alibaba.com> <4373f964-3336-d076-5284-d5a2983ddd88@linaro.org> Content-Language: en-US From: LIU Zhiwei In-Reply-To: <4373f964-3336-d076-5284-d5a2983ddd88@linaro.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=115.124.30.44; envelope-from=zhiwei_liu@linux.alibaba.com; helo=out30-44.freemail.mail.aliyun.com X-Spam_score_int: -98 X-Spam_score: -9.9 X-Spam_bar: --------- X-Spam_report: (-9.9 / 5.0 requ) BAYES_00=-1.9, ENV_AND_HDR_SPF_MATCH=-0.5, NICE_REPLY_A=-0.001, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, UNPARSEABLE_RELAY=0.001, USER_IN_DEF_SPF_WL=-7.5 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+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 2022/10/20 19:18, Richard Henderson wrote: > On 10/20/22 20:41, LIU Zhiwei wrote: >> When guest base is zero, we should use addr_regl as base regiser >> instead of >> the initial register TCG_REG_TMP0. >> >> Signed-off-by: LIU Zhiwei >> --- >>   tcg/riscv/tcg-target.c.inc | 4 ++++ >>   1 file changed, 4 insertions(+) >> >> diff --git a/tcg/riscv/tcg-target.c.inc b/tcg/riscv/tcg-target.c.inc >> index 81a83e45b1..32f4bc7bfc 100644 >> --- a/tcg/riscv/tcg-target.c.inc >> +++ b/tcg/riscv/tcg-target.c.inc >> @@ -1185,6 +1185,8 @@ static void tcg_out_qemu_ld(TCGContext *s, >> const TCGArg *args, bool is_64) >>       } >>       if (guest_base != 0) { >>           tcg_out_opc_reg(s, OPC_ADD, base, TCG_GUEST_BASE_REG, >> addr_regl); >> +    } else { >> +        base = addr_regl; >>       } > > You're right that there's a bug here, where TMP0 remains > uninitialized.  I think it would be better to reorg the other > direction: begin with initializeing base = addr_regl, Do you mean only in user mode? I see TCG_REG_TMP0 has been used in tcg_out_tlb_load when  system mode. Best Regards, Zhiwei > and then change it away only when we make modifications. > > r~