From nobody Tue Feb 10 08:31:29 2026 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.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; Authentication-Results: mx.zohomail.com; dkim=fail; spf=pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=linaro.org ARC-Seal: i=1; a=rsa-sha256; t=1557793242; cv=none; d=zoho.com; s=zohoarc; b=VoUjBJt3dXNI3fdilDhqxDJneE3UpPFI1DRV9itCV7w2/vERuoAkqMBXpSPlNqx+wtIWC9dID/bJeu8Hhs6pusjDLZdtgVHODru2AtKyvfH/bL8tcz2Yw2Rc89vyz8qw00ZbVcBaH0LmGJ7a/KhwPxAVCQPgKdMQ6B3/hy9m4gE= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zoho.com; s=zohoarc; t=1557793242; h=Content-Type:Content-Transfer-Encoding:Cc:Date:From:In-Reply-To:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:MIME-Version:Message-ID:References:Sender:Subject:To:ARC-Authentication-Results; bh=AEWllDC9QOtFQnoRVEZxCBNwIaVzx46hUstbb9Zao4Q=; b=KmPijwxhbKAYb+GhO179CJU6g/xocEEwGUh/Zm2+x+pKllU3eS+PeD8sfgOM8EgL9jA6t6VfaPe7CgGzKIX7A+p3WHQ49chzuE9E6gcRU2DVlvH/VfDfuI9zwf/Ob1J+fZbKsczATFTRsVQlmqoAxZsk24/PnkJ7mG8nQf6BXmE= ARC-Authentication-Results: i=1; mx.zoho.com; dkim=fail; spf=pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail header.from= (p=none dis=none) header.from= Return-Path: Received: from lists.gnu.org (209.51.188.17 [209.51.188.17]) by mx.zohomail.com with SMTPS id 1557793242491403.6087063295564; Mon, 13 May 2019 17:20:42 -0700 (PDT) Received: from localhost ([127.0.0.1]:36771 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hQLBM-00050S-BA for importer@patchew.org; Mon, 13 May 2019 20:20:36 -0400 Received: from eggs.gnu.org ([209.51.188.92]:59366) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hQL1y-0004h8-LP for qemu-devel@nongnu.org; Mon, 13 May 2019 20:11:53 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hQKxB-00038Q-7K for qemu-devel@nongnu.org; Mon, 13 May 2019 20:10:54 -0400 Received: from mail-pg1-x544.google.com ([2607:f8b0:4864:20::544]:44496) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1hQKx6-00031J-Tm for qemu-devel@nongnu.org; Mon, 13 May 2019 20:05:54 -0400 Received: by mail-pg1-x544.google.com with SMTP id z16so7585036pgv.11 for ; Mon, 13 May 2019 17:05:51 -0700 (PDT) Received: from localhost.localdomain (97-113-13-231.tukw.qwest.net. [97.113.13.231]) by smtp.gmail.com with ESMTPSA id u3sm238151pfn.29.2019.05.13.17.05.49 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 13 May 2019 17:05:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=AEWllDC9QOtFQnoRVEZxCBNwIaVzx46hUstbb9Zao4Q=; b=WaG4Tcz0PifdCR9WqNBKm4vpR6FCXO1PZsGdFXNeAI7otYI79ilijuObYWH6hj9dc+ nxwjfNt3iCs2mdi/im7S2z8bstp9G0XjUgX/W+tKxPzKXaH42kbEVExtvpgx99LYV2/1 EupqpCUEoVEV6+8Ujm49yDHHYrgINfF3Lc5hy8p2SlFnxhDDO27/VTaw3uyt9LJl69Ru zG9RleIxkr+VwZB/AEyy94C4RunGMCRtABk9jw7cCG/6glbaddrybl3BvHotdc0ph8vj gR9NpFSPgn9XtKHlRAqRuDaFvIcLydZDdZCTitGhIk1ew5Hh02o20gRMy1jTmTqpV4gN cMhw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=AEWllDC9QOtFQnoRVEZxCBNwIaVzx46hUstbb9Zao4Q=; b=gJcuSgFK0QH2nl1aKzSq0CZbd/YT/h+W+7yE1QtkO2ysSMwL1PuJpVL/+71Ztfc2P2 9SymOBHMeNbNMriJfqlPpYzfav11A181FpU3ORwBX1qzTsCsAEdhqnuOavAFy4kGWTpw lFM5iGIuZYMiVZs2XuQLS/muJcpwCYaZ21MLLxRXlG8TYkL/MHGXmeN+xt8iMIwfwsCx iw0YZQHQ/XIBhj/gI3jMtG1QMf7H1XPn7wcgnMGIuzxR8U4NgYBRanUEkpB6Jvm7zNo9 HEWpZQdRcHEJB0y4mCD3fMD9vsJtZIaW2bGHjeEJyjkzlpDhiqdQI2afOSzjIRL4f+kb CiPw== X-Gm-Message-State: APjAAAWddzncdbJ210mVszailiMmSQQ49VZceZIHVUDw/FjS4fAZLVzn F7rRjSUSOC9utEwz51dbckYmPnnDqw0= X-Google-Smtp-Source: APXvYqxzgymhRZeLTGd+uTDPLklKkVSdcN9v4CX05PWWnk6IT6Z5uVryFmn2XnQ172UOe98e99TZMw== X-Received: by 2002:a63:db10:: with SMTP id e16mr34890976pgg.142.1557792350421; Mon, 13 May 2019 17:05:50 -0700 (PDT) From: Richard Henderson To: qemu-devel@nongnu.org Date: Mon, 13 May 2019 17:05:14 -0700 Message-Id: <20190514000540.4313-6-richard.henderson@linaro.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190514000540.4313-1-richard.henderson@linaro.org> References: <20190514000540.4313-1-richard.henderson@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 2607:f8b0:4864:20::544 Subject: [Qemu-devel] [PULL 05/31] tcg: Assert fixed_reg is read-only X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: peter.maydell@linux.org Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) The only fixed_reg is cpu_env, and it should not be modified during any TB. Therefore code that tries to special-case moves into a fixed_reg is dead. Remove it. Reviewed-by: Alex Benn=C3=A9e Reviewed-by: David Hildenbrand Signed-off-by: Richard Henderson --- tcg/tcg.c | 87 +++++++++++++++++++++++++------------------------------ 1 file changed, 40 insertions(+), 47 deletions(-) diff --git a/tcg/tcg.c b/tcg/tcg.c index f7bef51de8..70ca113c26 100644 --- a/tcg/tcg.c +++ b/tcg/tcg.c @@ -3274,11 +3274,8 @@ static void tcg_reg_alloc_do_movi(TCGContext *s, TCG= Temp *ots, tcg_target_ulong val, TCGLifeData arg_li= fe, TCGRegSet preferred_regs) { - if (ots->fixed_reg) { - /* For fixed registers, we do not do any constant propagation. */ - tcg_out_movi(s, ots->type, ots->reg, val); - return; - } + /* ENV should not be modified. */ + tcg_debug_assert(!ots->fixed_reg); =20 /* The movi is not explicitly generated here. */ if (ots->val_type =3D=3D TEMP_VAL_REG) { @@ -3314,6 +3311,9 @@ static void tcg_reg_alloc_mov(TCGContext *s, const TC= GOp *op) ots =3D arg_temp(op->args[0]); ts =3D arg_temp(op->args[1]); =20 + /* ENV should not be modified. */ + tcg_debug_assert(!ots->fixed_reg); + /* Note that otype !=3D itype for no-op truncation. */ otype =3D ots->type; itype =3D ts->type; @@ -3338,7 +3338,7 @@ static void tcg_reg_alloc_mov(TCGContext *s, const TC= GOp *op) } =20 tcg_debug_assert(ts->val_type =3D=3D TEMP_VAL_REG); - if (IS_DEAD_ARG(0) && !ots->fixed_reg) { + if (IS_DEAD_ARG(0)) { /* mov to a non-saved dead register makes no sense (even with liveness analysis disabled). */ tcg_debug_assert(NEED_SYNC_ARG(0)); @@ -3351,7 +3351,7 @@ static void tcg_reg_alloc_mov(TCGContext *s, const TC= GOp *op) } temp_dead(s, ots); } else { - if (IS_DEAD_ARG(1) && !ts->fixed_reg && !ots->fixed_reg) { + if (IS_DEAD_ARG(1) && !ts->fixed_reg) { /* the mov can be suppressed */ if (ots->val_type =3D=3D TEMP_VAL_REG) { s->reg_to_temp[ots->reg] =3D NULL; @@ -3504,6 +3504,10 @@ static void tcg_reg_alloc_op(TCGContext *s, const TC= GOp *op) arg =3D op->args[i]; arg_ct =3D &def->args_ct[i]; ts =3D arg_temp(arg); + + /* ENV should not be modified. */ + tcg_debug_assert(!ts->fixed_reg); + if ((arg_ct->ct & TCG_CT_ALIAS) && !const_args[arg_ct->alias_index]) { reg =3D new_args[arg_ct->alias_index]; @@ -3512,29 +3516,21 @@ static void tcg_reg_alloc_op(TCGContext *s, const T= CGOp *op) i_allocated_regs | o_allocated_regs, op->output_pref[k], ts->indirect_base); } else { - /* if fixed register, we try to use it */ - reg =3D ts->reg; - if (ts->fixed_reg && - tcg_regset_test_reg(arg_ct->u.regs, reg)) { - goto oarg_end; - } reg =3D tcg_reg_alloc(s, arg_ct->u.regs, o_allocated_regs, op->output_pref[k], ts->indirect_base); } tcg_regset_set_reg(o_allocated_regs, reg); - /* if a fixed register is used, then a move will be done after= wards */ - if (!ts->fixed_reg) { - if (ts->val_type =3D=3D TEMP_VAL_REG) { - s->reg_to_temp[ts->reg] =3D NULL; - } - ts->val_type =3D TEMP_VAL_REG; - ts->reg =3D reg; - /* temp value is modified, so the value kept in memory is - potentially not the same */ - ts->mem_coherent =3D 0; - s->reg_to_temp[reg] =3D ts; + if (ts->val_type =3D=3D TEMP_VAL_REG) { + s->reg_to_temp[ts->reg] =3D NULL; } - oarg_end: + ts->val_type =3D TEMP_VAL_REG; + ts->reg =3D reg; + /* + * Temp value is modified, so the value kept in memory is + * potentially not the same. + */ + ts->mem_coherent =3D 0; + s->reg_to_temp[reg] =3D ts; new_args[i] =3D reg; } } @@ -3550,10 +3546,10 @@ static void tcg_reg_alloc_op(TCGContext *s, const T= CGOp *op) /* move the outputs in the correct register if needed */ for(i =3D 0; i < nb_oargs; i++) { ts =3D arg_temp(op->args[i]); - reg =3D new_args[i]; - if (ts->fixed_reg && ts->reg !=3D reg) { - tcg_out_mov(s, ts->type, ts->reg, reg); - } + + /* ENV should not be modified. */ + tcg_debug_assert(!ts->fixed_reg); + if (NEED_SYNC_ARG(i)) { temp_sync(s, ts, o_allocated_regs, 0, IS_DEAD_ARG(i)); } else if (IS_DEAD_ARG(i)) { @@ -3674,26 +3670,23 @@ static void tcg_reg_alloc_call(TCGContext *s, TCGOp= *op) for(i =3D 0; i < nb_oargs; i++) { arg =3D op->args[i]; ts =3D arg_temp(arg); + + /* ENV should not be modified. */ + tcg_debug_assert(!ts->fixed_reg); + reg =3D tcg_target_call_oarg_regs[i]; tcg_debug_assert(s->reg_to_temp[reg] =3D=3D NULL); - - if (ts->fixed_reg) { - if (ts->reg !=3D reg) { - tcg_out_mov(s, ts->type, ts->reg, reg); - } - } else { - if (ts->val_type =3D=3D TEMP_VAL_REG) { - s->reg_to_temp[ts->reg] =3D NULL; - } - ts->val_type =3D TEMP_VAL_REG; - ts->reg =3D reg; - ts->mem_coherent =3D 0; - s->reg_to_temp[reg] =3D ts; - if (NEED_SYNC_ARG(i)) { - temp_sync(s, ts, allocated_regs, 0, IS_DEAD_ARG(i)); - } else if (IS_DEAD_ARG(i)) { - temp_dead(s, ts); - } + if (ts->val_type =3D=3D TEMP_VAL_REG) { + s->reg_to_temp[ts->reg] =3D NULL; + } + ts->val_type =3D TEMP_VAL_REG; + ts->reg =3D reg; + ts->mem_coherent =3D 0; + s->reg_to_temp[reg] =3D ts; + if (NEED_SYNC_ARG(i)) { + temp_sync(s, ts, allocated_regs, 0, IS_DEAD_ARG(i)); + } else if (IS_DEAD_ARG(i)) { + temp_dead(s, ts); } } } --=20 2.17.1