From patchwork Sat May 4 05:52:34 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Richard Henderson X-Patchwork-Id: 10929553 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 516CC92A for ; Sat, 4 May 2019 05:57:37 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 3EED52880A for ; Sat, 4 May 2019 05:57:37 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 307C42881E; Sat, 4 May 2019 05:57:37 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.0 required=2.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 9BA2B2880A for ; Sat, 4 May 2019 05:57:36 +0000 (UTC) Received: from localhost ([127.0.0.1]:51658 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hMng0-0002tk-0B for patchwork-qemu-devel@patchwork.kernel.org; Sat, 04 May 2019 01:57:36 -0400 Received: from eggs.gnu.org ([209.51.188.92]:41711) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hMnbk-0007hC-Jm for qemu-devel@nongnu.org; Sat, 04 May 2019 01:53:13 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hMnbj-00049G-7S for qemu-devel@nongnu.org; Sat, 04 May 2019 01:53:12 -0400 Received: from mail-pg1-x541.google.com ([2607:f8b0:4864:20::541]:41225) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1hMnbj-00046t-0k for qemu-devel@nongnu.org; Sat, 04 May 2019 01:53:11 -0400 Received: by mail-pg1-x541.google.com with SMTP id z3so59852pgp.8 for ; Fri, 03 May 2019 22:53:09 -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=iZETl0exm2mwe37YJSYauOjqSn2X1yX7gYox/nsBAMwiKJdQ9pM2nw8TjCt0Zqp/dg akRinFecWNg3d7cuAhreaDiKKfc2h4ukjbnJmt5jtIuQ4qzRMsc+MKhwYV6jahXy4/B+ M3dTd5QPc+6ppPJmWKL1HvWk4BWpdXklZvoNrfBu3AplA8KOfAATbO93vu8HF73P6kkt MYgDCr87pn70ZT3nlC8TIQRGrzvuiONNcCWGnu940VZQUAtwFMrd0V/+60rqgKNcKrGI V6+BnsDa0dVIgHHNOiSgIZwlH9D6EVamgXpjtjV1ScqyUhkul93RZPEDB8WxhZNy6X7F rbKw== 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=YSbIO6z2t46i4MivprlyOgGny5UMKY33bf6gTQQmEcKMQVXolq6QicfFvzP72gYmiu VYEoCcY/Q2Qx5k3jAiYJk2NZzI4683i5g9t2cyTKYzAjQz94QyZ0/MibUZzdTbwkTzb4 EBVkWHGLg1DzHbA5/TYx83e12QB5M2nrFTizKDfyxd3tSYlNRsJDcoFZCmN3mffodu+b leOlvgacdjdxQl7YKld42O5T8mNPLFWGkiSzfvl+rkMvD8IDPQdbqhcfeFd7nNrb/v7o cl9zpArggWcBJFmL021cOHeaoG1J279XYOPt9CTah0/hbBrhGaM8VeGJQ/719YuM7XST efYw== X-Gm-Message-State: APjAAAVRrBqLe75MgUB5ivRNHZTPehYcVvlKdn6MexmRFVebqzl1q6Za DTNx8Bt+iKpAzlevbyLi1IIJVAyG2tA= X-Google-Smtp-Source: APXvYqxyNam82B17U5fIQry01SAviFw62+/q8QdMgU7+zsS6hmAw00m+afLnLZV6XfW13MASfkehZQ== X-Received: by 2002:a62:570a:: with SMTP id l10mr6751866pfb.151.1556949188537; Fri, 03 May 2019 22:53:08 -0700 (PDT) Received: from localhost.localdomain (97-113-189-189.tukw.qwest.net. [97.113.189.189]) by smtp.gmail.com with ESMTPSA id 15sm6680423pfo.117.2019.05.03.22.53.07 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 03 May 2019 22:53:07 -0700 (PDT) From: Richard Henderson To: qemu-devel@nongnu.org Date: Fri, 3 May 2019 22:52:34 -0700 Message-Id: <20190504055300.18426-6-richard.henderson@linaro.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190504055300.18426-1-richard.henderson@linaro.org> References: <20190504055300.18426-1-richard.henderson@linaro.org> MIME-Version: 1.0 X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 2607:f8b0:4864:20::541 Subject: [Qemu-devel] [PATCH v3 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: alex.bennee@linaro.org, david@redhat.com Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP 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 Bennée 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, TCGTemp *ots, tcg_target_ulong val, TCGLifeData arg_life, 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); /* The movi is not explicitly generated here. */ if (ots->val_type == TEMP_VAL_REG) { @@ -3314,6 +3311,9 @@ static void tcg_reg_alloc_mov(TCGContext *s, const TCGOp *op) ots = arg_temp(op->args[0]); ts = arg_temp(op->args[1]); + /* ENV should not be modified. */ + tcg_debug_assert(!ots->fixed_reg); + /* Note that otype != itype for no-op truncation. */ otype = ots->type; itype = ts->type; @@ -3338,7 +3338,7 @@ static void tcg_reg_alloc_mov(TCGContext *s, const TCGOp *op) } tcg_debug_assert(ts->val_type == 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 TCGOp *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 == TEMP_VAL_REG) { s->reg_to_temp[ots->reg] = NULL; @@ -3504,6 +3504,10 @@ static void tcg_reg_alloc_op(TCGContext *s, const TCGOp *op) arg = op->args[i]; arg_ct = &def->args_ct[i]; ts = 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 = new_args[arg_ct->alias_index]; @@ -3512,29 +3516,21 @@ static void tcg_reg_alloc_op(TCGContext *s, const TCGOp *op) i_allocated_regs | o_allocated_regs, op->output_pref[k], ts->indirect_base); } else { - /* if fixed register, we try to use it */ - reg = ts->reg; - if (ts->fixed_reg && - tcg_regset_test_reg(arg_ct->u.regs, reg)) { - goto oarg_end; - } reg = 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 afterwards */ - if (!ts->fixed_reg) { - if (ts->val_type == TEMP_VAL_REG) { - s->reg_to_temp[ts->reg] = NULL; - } - ts->val_type = TEMP_VAL_REG; - ts->reg = reg; - /* temp value is modified, so the value kept in memory is - potentially not the same */ - ts->mem_coherent = 0; - s->reg_to_temp[reg] = ts; + if (ts->val_type == TEMP_VAL_REG) { + s->reg_to_temp[ts->reg] = NULL; } - oarg_end: + ts->val_type = TEMP_VAL_REG; + ts->reg = reg; + /* + * Temp value is modified, so the value kept in memory is + * potentially not the same. + */ + ts->mem_coherent = 0; + s->reg_to_temp[reg] = ts; new_args[i] = reg; } } @@ -3550,10 +3546,10 @@ static void tcg_reg_alloc_op(TCGContext *s, const TCGOp *op) /* move the outputs in the correct register if needed */ for(i = 0; i < nb_oargs; i++) { ts = arg_temp(op->args[i]); - reg = new_args[i]; - if (ts->fixed_reg && ts->reg != 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 = 0; i < nb_oargs; i++) { arg = op->args[i]; ts = arg_temp(arg); + + /* ENV should not be modified. */ + tcg_debug_assert(!ts->fixed_reg); + reg = tcg_target_call_oarg_regs[i]; tcg_debug_assert(s->reg_to_temp[reg] == NULL); - - if (ts->fixed_reg) { - if (ts->reg != reg) { - tcg_out_mov(s, ts->type, ts->reg, reg); - } - } else { - if (ts->val_type == TEMP_VAL_REG) { - s->reg_to_temp[ts->reg] = NULL; - } - ts->val_type = TEMP_VAL_REG; - ts->reg = reg; - ts->mem_coherent = 0; - s->reg_to_temp[reg] = 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 == TEMP_VAL_REG) { + s->reg_to_temp[ts->reg] = NULL; + } + ts->val_type = TEMP_VAL_REG; + ts->reg = reg; + ts->mem_coherent = 0; + s->reg_to_temp[reg] = 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); } } }