From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 1059) id 5C1903851C27; Fri, 28 Aug 2020 15:56:28 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 5C1903851C27 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1598630188; bh=nFlH7dBLyN8W2LF51oLKus2vy4qtG3DL/xmyW0uQ2cU=; h=From:To:Subject:Date:From; b=AJG3zELPB0DjMuiuDNAeX3Ztq1YOBVHyirPVwP7heFEhFZXIYOM0DYbtmKPa4cYCx x4+05s0E3XzhM2gBvIJBSwDMdhTNywjuc4yFi064xD7tSCo9kCdESByGEGblBXeqBT SUUYgmmKrmhNbXujAFBE5WI/4Q2sS1jju/tBampA= Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit From: Nathan Sidwell To: gcc-cvs@gcc.gnu.org Subject: [gcc/devel/c++-modules] tree-optimization/94234 - add pattern for ptr-diff on addresses with same offset X-Act-Checkin: gcc X-Git-Author: Feng Xue X-Git-Refname: refs/heads/devel/c++-modules X-Git-Oldrev: 1e235788bbfc41f3eec1bb665d8e4bb2c63a1982 X-Git-Newrev: 459f6f68a75fe88e7c8309ca8ad3244a532b0d8e Message-Id: <20200828155628.5C1903851C27@sourceware.org> Date: Fri, 28 Aug 2020 15:56:28 +0000 (GMT) X-BeenThere: gcc-cvs@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-cvs mailing list List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 28 Aug 2020 15:56:28 -0000 https://gcc.gnu.org/g:459f6f68a75fe88e7c8309ca8ad3244a532b0d8e commit 459f6f68a75fe88e7c8309ca8ad3244a532b0d8e Author: Feng Xue Date: Mon Jun 1 11:57:35 2020 +0800 tree-optimization/94234 - add pattern for ptr-diff on addresses with same offset 2020-08-19 Feng Xue gcc/ PR tree-optimization/94234 * match.pd ((PTR_A + OFF) - (PTR_B + OFF)) -> (PTR_A - PTR_B): New simplification. gcc/testsuite/ PR tree-optimization/94234 * gcc.dg/pr94234-1.c: New test. Diff: --- gcc/match.pd | 3 +++ gcc/testsuite/gcc.dg/pr94234-1.c | 15 +++++++++++++++ 2 files changed, 18 insertions(+) diff --git a/gcc/match.pd b/gcc/match.pd index c3b88168ac4..2cffcae3d8b 100644 --- a/gcc/match.pd +++ b/gcc/match.pd @@ -2549,6 +2549,9 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT) && TREE_CODE (@2) == INTEGER_CST && tree_int_cst_sign_bit (@2) == 0)) (minus (convert @1) (convert @2))))) + (simplify + (pointer_diff (pointer_plus @0 @2) (pointer_plus @1 @2)) + (pointer_diff @0 @1)) (simplify (pointer_diff (pointer_plus @@0 @1) (pointer_plus @0 @2)) /* The second argument of pointer_plus must be interpreted as signed, and diff --git a/gcc/testsuite/gcc.dg/pr94234-1.c b/gcc/testsuite/gcc.dg/pr94234-1.c new file mode 100644 index 00000000000..d85563b32da --- /dev/null +++ b/gcc/testsuite/gcc.dg/pr94234-1.c @@ -0,0 +1,15 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -fdump-tree-forwprop1" } */ + +typedef __INTPTR_TYPE__ ssize_t; +typedef __PTRDIFF_TYPE__ ptrdiff_t; + +ptrdiff_t foo (char *a, ssize_t n, ssize_t m) +{ + char *b1 = a + 8 * n; + char *b2 = a + 8 * (n + 1); + + return (b1 + m) - (b2 + m); +} + +/* { dg-final { scan-tree-dump-times "return -8;" 1 "forwprop1" } } */