From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 1314) id C21023858C50; Fri, 10 Feb 2023 01:47:46 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org C21023858C50 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1675993666; bh=nztArkxBYdQYPS+CzgbHOug6RckXYNAFlTpc+30zibI=; h=From:To:Subject:Date:From; b=aVxbsSaZjnaWL5Y9zWt4R1zN3Gld0ta0q6h49mjXdXONjgjadchxm3bSTcb91A+yK hGKRnAnr2p7SJ5qv8jMZisAE02zfUJfJygUKRnQPoND+dfxxLxjrgMw3VACmYa6h/u +IkQxUqUqh/SB/FaUUDdDWXGY7/Z7FqBwLOoc8QE= MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="utf-8" From: Andrew Pinski To: gcc-cvs@gcc.gnu.org Subject: [gcc r13-5768] tree-optimization: [PR108684] ICE in verify_ssa due to simple_dce_from_worklist X-Act-Checkin: gcc X-Git-Author: Andrew Pinski X-Git-Refname: refs/heads/trunk X-Git-Oldrev: b9f8935e110c392c21460db838b4209c32f070c2 X-Git-Newrev: 6a5cb782d1486b378d70857c8efae558da0eb2cc Message-Id: <20230210014746.C21023858C50@sourceware.org> Date: Fri, 10 Feb 2023 01:47:46 +0000 (GMT) List-Id: https://gcc.gnu.org/g:6a5cb782d1486b378d70857c8efae558da0eb2cc commit r13-5768-g6a5cb782d1486b378d70857c8efae558da0eb2cc Author: Andrew Pinski Date: Tue Feb 7 23:09:40 2023 +0000 tree-optimization: [PR108684] ICE in verify_ssa due to simple_dce_from_worklist In simple_dce_from_worklist, we were removing an inline-asm which had a vdef. We should not be removing inline-asm which have a vdef as this code does not check to the store. This fixes that oversight. This was a latent bug exposed recently by both VRP and removal of stores to static starting to use simple_dce_from_worklist. Committed as approved. Bootstrapped and tested on x86_64-linux-gnu with no regressions. PR tree-optimization/108684 gcc/ChangeLog: * tree-ssa-dce.cc (simple_dce_from_worklist): Check all ssa names and not just non-vdef ones before accepting the inline-asm. Call unlink_stmt_vdef on the statement before removing it. gcc/testsuite/ChangeLog: * gcc.c-torture/compile/dce-inline-asm-1.c: New test. * gcc.c-torture/compile/dce-inline-asm-2.c: New test. * gcc.dg/tree-ssa/pr108684-1.c: New test. co-authored-by: Andrew Macleod Diff: --- gcc/testsuite/gcc.c-torture/compile/dce-inline-asm-1.c | 15 +++++++++++++++ gcc/testsuite/gcc.c-torture/compile/dce-inline-asm-2.c | 16 ++++++++++++++++ gcc/testsuite/gcc.dg/tree-ssa/pr108684-1.c | 18 ++++++++++++++++++ gcc/tree-ssa-dce.cc | 5 +++-- 4 files changed, 52 insertions(+), 2 deletions(-) diff --git a/gcc/testsuite/gcc.c-torture/compile/dce-inline-asm-1.c b/gcc/testsuite/gcc.c-torture/compile/dce-inline-asm-1.c new file mode 100644 index 00000000000..a9f02e44bd7 --- /dev/null +++ b/gcc/testsuite/gcc.c-torture/compile/dce-inline-asm-1.c @@ -0,0 +1,15 @@ +/* PR tree-optimization/108684 */ +/* This used to ICE as when we remove the store to + `t`, we also would remove the inline-asm which + had a VDEF on it but we didn't update the + VUSE that was later on. */ +static int t; + +int f (int *a) +{ + int t1; + asm (" " : "=X" (t1) : : "memory"); + t = t1; + return *a; +} + diff --git a/gcc/testsuite/gcc.c-torture/compile/dce-inline-asm-2.c b/gcc/testsuite/gcc.c-torture/compile/dce-inline-asm-2.c new file mode 100644 index 00000000000..a41b16e4bd0 --- /dev/null +++ b/gcc/testsuite/gcc.c-torture/compile/dce-inline-asm-2.c @@ -0,0 +1,16 @@ +/* PR tree-optimization/108684 */ +/* This used to ICE as when we removed the + __builtin_unreachable in VRP, as we + would also remove the branch and the + inline-asm. The inline-asm had a VDEF on it, + which we didn't update further along and + not have the VDEF on the return statement + updated. */ + +int f (int a) +{ + asm (" " : "=X" (a) : : "memory"); + if (a) + return 0; + __builtin_unreachable(); +} diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr108684-1.c b/gcc/testsuite/gcc.dg/tree-ssa/pr108684-1.c new file mode 100644 index 00000000000..3ba206f765e --- /dev/null +++ b/gcc/testsuite/gcc.dg/tree-ssa/pr108684-1.c @@ -0,0 +1,18 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -fdump-tree-optimized" } */ + + +static int t; + +int f (int *a) +{ + int t1, t2 = 0; + asm ("shouldshowupstill %1" : "=r" (t1), "=m"(t2) : : ); + t = t1; + return t2; +} + +/* Check to make sure DCE does not remove the inline-asm as it writes to t2. */ +/* We used to DCE this inline-asm when removing the store to t. */ +/* { dg-final { scan-assembler "shouldshowupstill" } } */ +/* { dg-final { scan-tree-dump-times "shouldshowupstill" 1 "optimized" } } */ diff --git a/gcc/tree-ssa-dce.cc b/gcc/tree-ssa-dce.cc index b2fe9f4f55e..1f1ec2c8710 100644 --- a/gcc/tree-ssa-dce.cc +++ b/gcc/tree-ssa-dce.cc @@ -2108,9 +2108,9 @@ simple_dce_from_worklist (bitmap worklist) /* The defining statement needs to be defining only this name. ASM is the only statement that can define more than one - (non-virtual) name. */ + name. */ if (is_a(t) - && !single_ssa_def_operand (t, SSA_OP_DEF)) + && !single_ssa_def_operand (t, SSA_OP_ALL_DEFS)) continue; /* Don't remove statements that are needed for non-call @@ -2140,6 +2140,7 @@ simple_dce_from_worklist (bitmap worklist) remove_phi_node (&gsi, true); else { + unlink_stmt_vdef (t); gsi_remove (&gsi, true); release_defs (t); }