From patchwork Thu Sep 27 17:19:57 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Richard Henderson X-Patchwork-Id: 187418 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 72A072C007F for ; Fri, 28 Sep 2012 03:26:13 +1000 (EST) Received: from localhost ([::1]:45321 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1THHql-0006NO-HX for incoming@patchwork.ozlabs.org; Thu, 27 Sep 2012 13:26:11 -0400 Received: from eggs.gnu.org ([208.118.235.92]:54900) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1THHqY-0006Ew-AQ for qemu-devel@nongnu.org; Thu, 27 Sep 2012 13:25:59 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1THHqT-0005W7-P2 for qemu-devel@nongnu.org; Thu, 27 Sep 2012 13:25:58 -0400 Received: from mail-pb0-f45.google.com ([209.85.160.45]:39647) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1THHqT-0004ys-Hm for qemu-devel@nongnu.org; Thu, 27 Sep 2012 13:25:53 -0400 Received: by mail-pb0-f45.google.com with SMTP id rp2so3912471pbb.4 for ; Thu, 27 Sep 2012 10:25:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=sender:from:to:cc:subject:date:message-id:x-mailer:in-reply-to :references; bh=Dkpkf853m5x1jjacYg9HvnUnI291pZ5Eu5Svt/Us3x8=; b=QA93db0GUyG078VfFklckl9IX2migCUOVBbUJ1jMxMgHo/DU1rkiKr3pkweoG5H0kM dt9a5w7/BDSLT+apGHNTa2CPphxI8kPWUzm6QkukTWkc9CfrzquGoBEzQzPMmQ8g1W/W HMoAl7jiVyX3IG21rqTnSbf43+lsoJSinvz7RKgvOTEsRl+rIvMz+4DCBMQ20OaTKeCY nf7SzROIHWASs3eNYK1rbWi4U1Gpx6OHMuyUFgBSmCqThk7/95+cDh+HtVfxcvzXZ8Wa RtsbsMZ9n50CXexRYsDk+L+FXfJ3REBszI6MAXBlBJD4RsT+E/hH9YgKOwODoVvVk+I4 0Sww== Received: by 10.68.235.71 with SMTP id uk7mr13463058pbc.10.1348766414265; Thu, 27 Sep 2012 10:20:14 -0700 (PDT) Received: from anchor.twiddle.home.com ([173.160.232.49]) by mx.google.com with ESMTPS id jw14sm4118581pbb.36.2012.09.27.10.20.13 (version=TLSv1/SSLv3 cipher=OTHER); Thu, 27 Sep 2012 10:20:13 -0700 (PDT) From: Richard Henderson To: qemu-devel@nongnu.org Date: Thu, 27 Sep 2012 10:19:57 -0700 Message-Id: <1348766397-20731-8-git-send-email-rth@twiddle.net> X-Mailer: git-send-email 1.7.11.4 In-Reply-To: <1348766397-20731-1-git-send-email-rth@twiddle.net> References: <1348766397-20731-1-git-send-email-rth@twiddle.net> X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 209.85.160.45 Cc: Aurelien Jarno Subject: [Qemu-devel] [PATCH 7/7] tcg: Do constant folding on double-word comparisons 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 Signed-off-by: Richard Henderson Reviewed-by: Aurelien Jarno --- tcg/optimize.c | 134 ++++++++++++++++++++++++++++++++++++++++----------------- 1 file changed, 94 insertions(+), 40 deletions(-) diff --git a/tcg/optimize.c b/tcg/optimize.c index dfac877..f6a16fd 100644 --- a/tcg/optimize.c +++ b/tcg/optimize.c @@ -398,6 +398,40 @@ static TCGArg do_constant_folding_cond(TCGOpcode op, TCGArg x, } } +/* Return 2 if the condition can't be simplified, and the result + of the condition (0 or 1) if it can */ +static TCGArg do_constant_folding_cond2(TCGArg *p1, TCGArg *p2, TCGCond c) +{ + TCGArg al = p1[0], ah = p1[1]; + TCGArg bl = p2[0], bh = p2[1]; + + if (temps[bl].state == TCG_TEMP_CONST + && temps[bh].state == TCG_TEMP_CONST) { + uint64_t b = ((uint64_t)temps[bh].val << 32) | (uint32_t)temps[bl].val; + + if (temps[al].state == TCG_TEMP_CONST + && temps[ah].state == TCG_TEMP_CONST) { + uint64_t a; + a = ((uint64_t)temps[ah].val << 32) | (uint32_t)temps[al].val; + return do_constant_folding_cond_64(a, b, c); + } + if (b == 0) { + switch (c) { + case TCG_COND_LTU: + return 0; + case TCG_COND_GEU: + return 1; + default: + break; + } + } + } + if (temps_are_copies(al, bl) && temps_are_copies(ah, bh)) { + return do_constant_folding_cond_eq(c); + } + return 2; +} + static bool swap_commutative(TCGArg dest, TCGArg *p1, TCGArg *p2) { TCGArg a1 = *p1, a2 = *p2; @@ -816,53 +850,73 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr, args += 6; break; case INDEX_op_brcond2_i32: - /* Simplify LT/GE comparisons vs zero to a single compare - vs the high word of the input. */ - if ((args[4] == TCG_COND_LT || args[4] == TCG_COND_GE) - && temps[args[2]].state == TCG_TEMP_CONST - && temps[args[3]].state == TCG_TEMP_CONST - && temps[args[2]].val == 0 - && temps[args[2]].val == 0) { - gen_opc_buf[op_index] = INDEX_op_brcond_i32; - args[0] = args[1]; - args[1] = args[3]; - args[2] = args[4]; - args[3] = args[5]; - gen_args += 4; + tmp = do_constant_folding_cond2(&args[0], &args[2], args[4]); + if (tmp != 2) { + if (tmp) { + gen_opc_buf[op_index] = INDEX_op_br; + gen_args[0] = args[5]; + gen_args += 1; + } else { + gen_opc_buf[op_index] = INDEX_op_nop; + args += 6; + break; + } } else { - gen_args[0] = args[0]; - gen_args[1] = args[1]; - gen_args[2] = args[2]; - gen_args[3] = args[3]; - gen_args[4] = args[4]; - gen_args[5] = args[5]; - gen_args += 6; + /* Simplify LT/GE comparisons vs zero to a single compare + vs the high word of the input. */ + if ((args[4] == TCG_COND_LT || args[4] == TCG_COND_GE) + && temps[args[2]].state == TCG_TEMP_CONST + && temps[args[3]].state == TCG_TEMP_CONST + && temps[args[2]].val == 0 + && temps[args[2]].val == 0) { + gen_opc_buf[op_index] = INDEX_op_brcond_i32; + args[0] = args[1]; + args[1] = args[3]; + args[2] = args[4]; + args[3] = args[5]; + gen_args += 4; + } else { + gen_args[0] = args[0]; + gen_args[1] = args[1]; + gen_args[2] = args[2]; + gen_args[3] = args[3]; + gen_args[4] = args[4]; + gen_args[5] = args[5]; + gen_args += 6; + } } memset(temps, 0, nb_temps * sizeof(struct tcg_temp_info)); args += 6; break; case INDEX_op_setcond2_i32: - /* Simplify LT/GE comparisons vs zero to a single compare - vs the high word of the input. */ - if ((args[5] == TCG_COND_LT || args[5] == TCG_COND_GE) - && temps[args[3]].state == TCG_TEMP_CONST - && temps[args[4]].state == TCG_TEMP_CONST - && temps[args[3]].val == 0 - && temps[args[4]].val == 0) { - gen_opc_buf[op_index] = INDEX_op_setcond_i32; - args[1] = args[2]; - args[2] = args[4]; - args[3] = args[5]; - gen_args += 4; + tmp = do_constant_folding_cond2(&args[1], &args[3], args[5]); + if (tmp != 2) { + gen_opc_buf[op_index] = INDEX_op_movi_i32; + tcg_opt_gen_movi(gen_args, args[0], tmp); + gen_args += 2; } else { - reset_temp(args[0]); - gen_args[0] = args[0]; - gen_args[1] = args[1]; - gen_args[2] = args[2]; - gen_args[3] = args[3]; - gen_args[4] = args[4]; - gen_args[5] = args[5]; - gen_args += 6; + /* Simplify LT/GE comparisons vs zero to a single compare + vs the high word of the input. */ + if ((args[5] == TCG_COND_LT || args[5] == TCG_COND_GE) + && temps[args[3]].state == TCG_TEMP_CONST + && temps[args[4]].state == TCG_TEMP_CONST + && temps[args[3]].val == 0 + && temps[args[4]].val == 0) { + gen_opc_buf[op_index] = INDEX_op_setcond_i32; + args[1] = args[2]; + args[2] = args[4]; + args[3] = args[5]; + gen_args += 4; + } else { + reset_temp(args[0]); + gen_args[0] = args[0]; + gen_args[1] = args[1]; + gen_args[2] = args[2]; + gen_args[3] = args[3]; + gen_args[4] = args[4]; + gen_args[5] = args[5]; + gen_args += 6; + } } args += 6; break;