From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 1666) id E9F973858C3A; Mon, 23 Oct 2023 10:35:03 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org E9F973858C3A DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1698057303; bh=GbHCcaKtfK1jwt7RLYUTgyzpNSa33cM2bq9vlVHFFFQ=; h=From:To:Subject:Date:From; b=fIn//lgyOxrMqEnH7ltmy+ZAu3KiLC0XJCnChmFiJ8Mvw5ZTgEKcvNVnOPyhv5ISD CaYId+coOiuKxj7I9WoVtNokzFEmKuTFIpbLc37JXjzWfCK2taCbhBbdnmGv2bRH4H 923sDmZwIZYcNvciYj1xTr5hBZyiH4f8xEITrI3w= MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="utf-8" From: Richard Biener To: gcc-cvs@gcc.gnu.org Subject: [gcc r14-4857] tree-optimization/111917 - bougs IL after guard hoisting X-Act-Checkin: gcc X-Git-Author: Richard Biener X-Git-Refname: refs/heads/master X-Git-Oldrev: 0c4bd1321a6def5eb44c530e83b01a415633b660 X-Git-Newrev: d96bd4aade170fcd86f5f09b68b770dde798e631 Message-Id: <20231023103503.E9F973858C3A@sourceware.org> Date: Mon, 23 Oct 2023 10:35:03 +0000 (GMT) List-Id: https://gcc.gnu.org/g:d96bd4aade170fcd86f5f09b68b770dde798e631 commit r14-4857-gd96bd4aade170fcd86f5f09b68b770dde798e631 Author: Richard Biener Date: Mon Oct 23 11:25:17 2023 +0200 tree-optimization/111917 - bougs IL after guard hoisting The unswitching code to hoist guards inserts conditions in wrong places. The following fixes this, simplifying code. PR tree-optimization/111917 * tree-ssa-loop-unswitch.cc (hoist_guard): Always insert new conditional after last stmt. * gcc.dg/torture/pr111917.c: New testcase. Diff: --- gcc/testsuite/gcc.dg/torture/pr111917.c | 23 +++++++++++++++++++++++ gcc/tree-ssa-loop-unswitch.cc | 5 +---- 2 files changed, 24 insertions(+), 4 deletions(-) diff --git a/gcc/testsuite/gcc.dg/torture/pr111917.c b/gcc/testsuite/gcc.dg/torture/pr111917.c new file mode 100644 index 000000000000..532e30200b59 --- /dev/null +++ b/gcc/testsuite/gcc.dg/torture/pr111917.c @@ -0,0 +1,23 @@ +/* { dg-do compile } */ +/* { dg-additional-options "-funswitch-loops" } */ + +long t; +long a() { + long b = t, c = t; + for (; b < 31; b++) + c <<= 1; + return c; +} +long t1; +static +int d() { + if (!t1) + return 0; +e: +f: + for (; a();) + ; + goto f; + return 0; +} +int main() { d(); } diff --git a/gcc/tree-ssa-loop-unswitch.cc b/gcc/tree-ssa-loop-unswitch.cc index 619b50fb4bb0..b4611ac82561 100644 --- a/gcc/tree-ssa-loop-unswitch.cc +++ b/gcc/tree-ssa-loop-unswitch.cc @@ -1455,10 +1455,7 @@ hoist_guard (class loop *loop, edge guard) cond_stmt = as_a (stmt); extract_true_false_edges_from_block (guard_bb, &te, &fe); /* Insert guard to PRE_HEADER. */ - if (!empty_block_p (pre_header)) - gsi = gsi_last_bb (pre_header); - else - gsi = gsi_start_bb (pre_header); + gsi = gsi_last_bb (pre_header); /* Create copy of COND_STMT. */ new_cond_stmt = gimple_build_cond (gimple_cond_code (cond_stmt), gimple_cond_lhs (cond_stmt),