From 7061cfc027e29b6d276ef5e09835c93899cfd132 Mon Sep 17 00:00:00 2001 From: Bin Cheng Date: Tue, 1 Aug 2017 09:20:08 +0000 Subject: [PATCH] re PR tree-optimization/81627 (ICE on valid code at -O3: in check_loop_closed_ssa_use, at tree-ssa-loop-manip.c:707) PR tree-optimization/81627 * tree-predcom.c (prepare_finalizers): Always rewrite into loop closed ssa form for store-store chain. gcc/testsuite * gcc.dg/tree-ssa/pr81627.c: New. From-SVN: r250764 --- gcc/ChangeLog | 6 ++++++ gcc/testsuite/ChangeLog | 5 +++++ gcc/testsuite/gcc.dg/tree-ssa/pr81627.c | 28 +++++++++++++++++++++++++ gcc/tree-predcom.c | 10 ++++----- 4 files changed, 44 insertions(+), 5 deletions(-) create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/pr81627.c diff --git a/gcc/ChangeLog b/gcc/ChangeLog index c8ed19d41ad..9e09d56d2b2 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,9 @@ +2017-08-01 Bin Cheng + + PR tree-optimization/81627 + * tree-predcom.c (prepare_finalizers): Always rewrite into loop + closed ssa form for store-store chain. + 2017-08-01 Bin Cheng PR tree-optimization/81620 diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index e2f695fa001..a86b281157e 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2017-08-01 Bin Cheng + + PR tree-optimization/81627 + * gcc.dg/tree-ssa/pr81627.c: New. + 2017-08-01 Bin Cheng PR tree-optimization/81620 diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr81627.c b/gcc/testsuite/gcc.dg/tree-ssa/pr81627.c new file mode 100644 index 00000000000..9ba43be5052 --- /dev/null +++ b/gcc/testsuite/gcc.dg/tree-ssa/pr81627.c @@ -0,0 +1,28 @@ +/* { dg-do run } */ +/* { dg-options "-O3 -fno-tree-loop-vectorize -fdump-tree-pcom-details" } */ + +int a, b, c, d[6], e = 3, f; + +void abort (void); +void fn1 () +{ + for (b = 1; b < 5; b++) + { + for (c = 0; c < 5; c++) + d[b] = e; + if (a) + f++; + d[b + 1] = 1; + } +} + +int main () +{ + fn1 (); + if (d[0] != 0 || d[1] != 3 || d[2] != 3 + || d[3] != 3 || d[4] != 3 || d[5] != 1) + abort (); + + return 0; +} +/* { dg-final { scan-tree-dump-times "Store-stores chain" 1 "pcom" } } */ diff --git a/gcc/tree-predcom.c b/gcc/tree-predcom.c index f7a57a43a0e..4538773552c 100644 --- a/gcc/tree-predcom.c +++ b/gcc/tree-predcom.c @@ -2983,11 +2983,11 @@ prepare_finalizers (struct loop *loop, vec chains) if (prepare_finalizers_chain (loop, chain)) { i++; - /* We don't corrupt loop closed ssa form for store elimination - chain if eliminated stores only store loop invariant values - into memory. */ - if (!chain->inv_store_elimination) - loop_closed_ssa |= (!chain->inv_store_elimination); + /* Be conservative, assume loop closed ssa form is corrupted + by store-store chain. Though it's not always the case if + eliminated stores only store loop invariant values into + memory. */ + loop_closed_ssa = true; } else { -- 2.30.2