From patchwork Fri Jul 22 12:07:24 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Stubbs X-Patchwork-Id: 3048 Return-Path: X-Original-To: patchwork@peony.canonical.com Delivered-To: patchwork@peony.canonical.com Received: from fiordland.canonical.com (fiordland.canonical.com [91.189.94.145]) by peony.canonical.com (Postfix) with ESMTP id 6DC3D23F18 for ; Fri, 22 Jul 2011 12:07:32 +0000 (UTC) Received: from mail-qw0-f52.google.com (mail-qw0-f52.google.com [209.85.216.52]) by fiordland.canonical.com (Postfix) with ESMTP id 1EB51A180D9 for ; Fri, 22 Jul 2011 12:07:32 +0000 (UTC) Received: by qwb8 with SMTP id 8so1559336qwb.11 for ; Fri, 22 Jul 2011 05:07:31 -0700 (PDT) Received: by 10.229.68.200 with SMTP id w8mr1261923qci.114.1311336451522; Fri, 22 Jul 2011 05:07:31 -0700 (PDT) X-Forwarded-To: linaro-patchwork@canonical.com X-Forwarded-For: patch@linaro.org linaro-patchwork@canonical.com Delivered-To: patches@linaro.org Received: by 10.229.217.78 with SMTP id hl14cs12586qcb; Fri, 22 Jul 2011 05:07:31 -0700 (PDT) Received: by 10.236.153.163 with SMTP id f23mr2124174yhk.60.1311336450841; Fri, 22 Jul 2011 05:07:30 -0700 (PDT) Received: from mail.codesourcery.com (mail.codesourcery.com [38.113.113.100]) by mx.google.com with ESMTPS id y2si5966763icw.88.2011.07.22.05.07.29 (version=TLSv1/SSLv3 cipher=OTHER); Fri, 22 Jul 2011 05:07:29 -0700 (PDT) Received-SPF: pass (google.com: domain of ams@codesourcery.com designates 38.113.113.100 as permitted sender) client-ip=38.113.113.100; Authentication-Results: mx.google.com; spf=pass (google.com: domain of ams@codesourcery.com designates 38.113.113.100 as permitted sender) smtp.mail=ams@codesourcery.com Received: (qmail 17062 invoked from network); 22 Jul 2011 12:07:27 -0000 Received: from unknown (HELO ?192.168.0.104?) (ams@127.0.0.2) by mail.codesourcery.com with ESMTPA; 22 Jul 2011 12:07:27 -0000 Message-ID: <4E2967FC.3090101@codesourcery.com> Date: Fri, 22 Jul 2011 13:07:24 +0100 From: Andrew Stubbs User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:5.0) Gecko/20110627 Thunderbird/5.0 MIME-Version: 1.0 CC: Richard Guenther , gcc-patches@gcc.gnu.org, patches@linaro.org Subject: Re: [PATCH (9/7)] Widening multiplies with constant inputs References: <4E034EF2.3070503@codesourcery.com> <4E282148.9080100@codesourcery.com> <4E2965A5.1080301@codesourcery.com> In-Reply-To: <4E2965A5.1080301@codesourcery.com> ENOPATCH .... On 22/07/11 12:57, Andrew Stubbs wrote: > On 21/07/11 14:22, Richard Guenther wrote: >> On Thu, Jul 21, 2011 at 2:53 PM, Andrew Stubbs >> wrote: >>> This patch is part bug fix, part better optimization. >>> >>> Firstly, my initial patch series introduced a bug that caused an >>> internal >>> compiler error when the input to a multiply was a constant. This was >>> caused >>> by the gimple verification rejecting such things. I'm not totally >>> clear how >>> this ever worked, but I've corrected it by inserting a temporary >>> SSA_NAME >>> between the constant and the multiply. >> >> Huh? Constant operands should be perfectly fine. What was the error >> you got? > > Ok, so it seems that the fold_convert we thought was redundant in patch > 5 (now moved to patch 2) was in fact responsible for making constants > the right type. > > I've rewritten it to use fold_convert to change the constant. > >>> I also discovered that widening multiply-and-accumulate operations >>> were not >>> recognised if any one of the three inputs were a constant. I've >>> corrected >>> this by adjusting the pattern matching. This also required inserting new >>> SSA_NAMEs to make it work. >> >> See above. > > The pattern matching stuff remains the same, but the constant > conversions have been updated. > >>> In order to insert the new SSA_NAME, I've simply reused the existing >>> type >>> conversion code - the only difference is that the conversion may be a >>> no-op, >>> so it just generates a straight forward assignment. >>> >>> OK? >> >> Nope. I suppose you forget to adjust the constants type? Just >> fold-convert it before using it as input to a macc. > > Done. > > OK? > > Andrew > 2011-07-22 Andrew Stubbs gcc/ * tree-ssa-math-opts.c (is_widening_mult_rhs_p): Handle constants beyond conversions. (convert_mult_to_widen): Convert constant inputs to the right type. (convert_plusminus_to_widen): Don't automatically reject inputs that are not an SSA_NAME. Convert constant inputs to the right type. gcc/testsuite/ * gcc.target/arm/wmul-11.c: New file. * gcc.target/arm/wmul-12.c: New file. * gcc.target/arm/wmul-13.c: New file. --- /dev/null +++ b/gcc/testsuite/gcc.target/arm/wmul-11.c @@ -0,0 +1,11 @@ +/* { dg-do compile } */ +/* { dg-options "-O2" } */ +/* { dg-require-effective-target arm_dsp } */ + +long long +foo (int *b) +{ + return 10 * (long long)*b; +} + +/* { dg-final { scan-assembler "smull" } } */ --- /dev/null +++ b/gcc/testsuite/gcc.target/arm/wmul-12.c @@ -0,0 +1,12 @@ +/* { dg-do compile } */ +/* { dg-options "-O2" } */ +/* { dg-require-effective-target arm_dsp } */ + +long long +foo (int *b, int *c) +{ + int tmp = *b * *c; + return 10 + (long long)tmp; +} + +/* { dg-final { scan-assembler "smlal" } } */ --- /dev/null +++ b/gcc/testsuite/gcc.target/arm/wmul-13.c @@ -0,0 +1,11 @@ +/* { dg-do compile } */ +/* { dg-options "-O2" } */ +/* { dg-require-effective-target arm_dsp } */ + +long long +foo (int *a, int *b) +{ + return *a + (long long)*b * 10; +} + +/* { dg-final { scan-assembler "smlal" } } */ --- a/gcc/tree-ssa-math-opts.c +++ b/gcc/tree-ssa-math-opts.c @@ -1997,6 +1997,13 @@ is_widening_mult_rhs_p (tree type, tree rhs, tree *type_out, type1 = TREE_TYPE (rhs1); } + if (TREE_CODE (rhs1) == INTEGER_CST) + { + *new_rhs_out = rhs1; + *type_out = NULL; + return true; + } + if (TREE_CODE (type1) != TREE_CODE (type) || TYPE_PRECISION (type1) * 2 > TYPE_PRECISION (type)) return false; @@ -2170,6 +2177,12 @@ convert_mult_to_widen (gimple stmt, gimple_stmt_iterator *gsi) rhs2 = build_and_insert_cast (gsi, loc, tmp, rhs2); } + /* Handle constants. */ + if (TREE_CODE (rhs1) == INTEGER_CST) + rhs1 = fold_convert (type1, rhs1); + if (TREE_CODE (rhs2) == INTEGER_CST) + rhs2 = fold_convert (type2, rhs2); + gimple_assign_set_rhs1 (stmt, rhs1); gimple_assign_set_rhs2 (stmt, rhs2); gimple_assign_set_rhs_code (stmt, WIDEN_MULT_EXPR); @@ -2221,8 +2234,6 @@ convert_plusminus_to_widen (gimple_stmt_iterator *gsi, gimple stmt, if (is_gimple_assign (rhs1_stmt)) rhs1_code = gimple_assign_rhs_code (rhs1_stmt); } - else - return false; if (TREE_CODE (rhs2) == SSA_NAME) { @@ -2230,8 +2241,6 @@ convert_plusminus_to_widen (gimple_stmt_iterator *gsi, gimple stmt, if (is_gimple_assign (rhs2_stmt)) rhs2_code = gimple_assign_rhs_code (rhs2_stmt); } - else - return false; /* Allow for one conversion statement between the multiply and addition/subtraction statement. If there are more than @@ -2379,6 +2388,12 @@ convert_plusminus_to_widen (gimple_stmt_iterator *gsi, gimple stmt, add_rhs = build_and_insert_cast (gsi, loc, create_tmp_var (type, NULL), add_rhs); + /* Handle constants. */ + if (TREE_CODE (mult_rhs1) == INTEGER_CST) + rhs1 = fold_convert (type1, mult_rhs1); + if (TREE_CODE (mult_rhs2) == INTEGER_CST) + rhs2 = fold_convert (type2, mult_rhs2); + gimple_assign_set_rhs_with_ops_1 (gsi, wmult_code, mult_rhs1, mult_rhs2, add_rhs); update_stmt (gsi_stmt (*gsi));