From patchwork Thu Jan 24 04:03:22 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Richard Henderson X-Patchwork-Id: 215209 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 572E92C0040 for ; Thu, 24 Jan 2013 15:27:03 +1100 (EST) Received: from localhost ([::1]:58745 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TyEOz-0000KD-9Z for incoming@patchwork.ozlabs.org; Wed, 23 Jan 2013 23:27:01 -0500 Received: from eggs.gnu.org ([208.118.235.92]:55767) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TyEOj-000060-Mq for qemu-devel@nongnu.org; Wed, 23 Jan 2013 23:26:51 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1TyEOg-0001FO-NI for qemu-devel@nongnu.org; Wed, 23 Jan 2013 23:26:45 -0500 Received: from mail-pa0-f44.google.com ([209.85.220.44]:39056) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TyE3U-0004Rl-SB for qemu-devel@nongnu.org; Wed, 23 Jan 2013 23:04:48 -0500 Received: by mail-pa0-f44.google.com with SMTP id hz11so5225536pad.3 for ; Wed, 23 Jan 2013 20:04:48 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=x-received:sender:from:to:cc:subject:date:message-id:x-mailer :in-reply-to:references; bh=A1Nkl41aNgSGGdix+3qKTWqAwqWT7dhTErsOrnCOOWE=; b=Sfsf0cN0kjx3UxhjtBNlg3k+x5NrEEzs0VyYNzSNo3Md8rk3rEOp+rzKGFhJyH5pze 9zdcIQNeHthamejIeutwe/Vc2vCkcRLtOOF8lcdqKBUh71fjceonYo0UqiRf7LqI+eW/ 0MLIJwfoXiazvWahuJ2JmNDe9CtGXRTNM+OB5rPHb9q60t8HKklTIdizQ2FZdy5W0GAa qz6Ozr1yD4FUX5eCggX+RIs2//r/OFQ6nVc67/Ts6IpUVL+Ka3PoW7DUxEXgCAb5mfha zxr565d9I6st7utFKyE81ScRwRWgW7SvtIb4qsrPvvgXrru9VKQnnMpdnnthETgeLpVQ 0HQQ== X-Received: by 10.66.81.199 with SMTP id c7mr1384508pay.39.1359000288240; Wed, 23 Jan 2013 20:04:48 -0800 (PST) Received: from anchor.twiddle.home (50-194-63-110-static.hfc.comcastbusiness.net. [50.194.63.110]) by mx.google.com with ESMTPS id ot3sm14027480pbb.38.2013.01.23.20.04.46 (version=TLSv1 cipher=RC4-SHA bits=128/128); Wed, 23 Jan 2013 20:04:47 -0800 (PST) From: Richard Henderson To: qemu-devel@nongnu.org Date: Wed, 23 Jan 2013 20:03:22 -0800 Message-Id: <1359000221-19834-39-git-send-email-rth@twiddle.net> X-Mailer: git-send-email 1.7.11.7 In-Reply-To: <1359000221-19834-1-git-send-email-rth@twiddle.net> References: <1359000221-19834-1-git-send-email-rth@twiddle.net> X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x [fuzzy] X-Received-From: 209.85.220.44 Cc: Blue Swirl , Paolo Bonzini Subject: [Qemu-devel] [PATCH 38/57] target-i386: Update cc_op before TCG branches X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Placing the CC_OP_DYNAMIC at the join is less effective than before the branch, as the branch will have forced global registers to their home locations. This way we have a chance to discard CC_SRC2 before it gets stored. Signed-off-by: Richard Henderson --- target-i386/translate.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/target-i386/translate.c b/target-i386/translate.c index 9f031a8..b3ba93e 100644 --- a/target-i386/translate.c +++ b/target-i386/translate.c @@ -1552,8 +1552,9 @@ static void gen_shift_rm_T1(DisasContext *s, int ot, int op1, gen_op_mov_reg_T0(ot, op1); } - /* update eflags */ + /* Update eflags data because we cannot predict flags afterward. */ gen_update_cc_op(s); + set_cc_op(s, CC_OP_DYNAMIC); tcg_gen_mov_tl(t1, cpu_T[0]); @@ -1580,7 +1581,6 @@ static void gen_shift_rm_T1(DisasContext *s, int ot, int op1, } gen_set_label(shift_label); - set_cc_op(s, CC_OP_DYNAMIC); /* cannot predict flags after */ tcg_temp_free(t0); tcg_temp_free(t1); @@ -1965,8 +1965,9 @@ static void gen_shiftd_rm_T1(DisasContext *s, int ot, int op1, gen_op_mov_reg_v(ot, op1, t0); } - /* update eflags */ + /* Update eflags data because we cannot predict flags afterward. */ gen_update_cc_op(s); + set_cc_op(s, CC_OP_DYNAMIC); label2 = gen_new_label(); tcg_gen_brcondi_tl(TCG_COND_EQ, t2, 0, label2); @@ -1979,7 +1980,6 @@ static void gen_shiftd_rm_T1(DisasContext *s, int ot, int op1, tcg_gen_movi_i32(cpu_cc_op, CC_OP_SHLB + ot); } gen_set_label(label2); - set_cc_op(s, CC_OP_DYNAMIC); /* cannot predict flags after */ tcg_temp_free(t0); tcg_temp_free(t1);