From 87af2d007d4270d3bdec1de8bcd22fac1d191fcd Mon Sep 17 00:00:00 2001 From: jakub Date: Tue, 17 Jan 2012 10:38:38 +0000 Subject: [PATCH] PR tree-optimization/51877 * tree-ssa-tail-merge.c (gimple_equal_p): Don't return true whenever call arguments and fndecls compare equal, instead return false if they don't. Return true only if lhs1 and lhs2 are either both NULL, or both SSA_NAMEs that are valueized the same, or they satisfy operand_equal_p. * gcc.c-torture/execute/pr51877.c: New test. git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@183237 138bc75d-0d04-0410-961f-82ee72b054a4 --- gcc/ChangeLog | 9 +++++ gcc/testsuite/ChangeLog | 5 +++ gcc/testsuite/gcc.c-torture/execute/pr51877.c | 50 +++++++++++++++++++++++++++ gcc/tree-ssa-tail-merge.c | 16 +++++---- 4 files changed, 74 insertions(+), 6 deletions(-) create mode 100644 gcc/testsuite/gcc.c-torture/execute/pr51877.c diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 4d3a46fe6ea..b0765b8676c 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,12 @@ +2012-01-17 Jakub Jelinek + + PR tree-optimization/51877 + * tree-ssa-tail-merge.c (gimple_equal_p): Don't return true whenever + call arguments and fndecls compare equal, instead return false if they + don't. Return true only if lhs1 and lhs2 are either both NULL, or + both SSA_NAMEs that are valueized the same, or they satisfy + operand_equal_p. + 2012-01-17 Rainer Orth * configure.ac (gcc_cv_target_dl_iterate_phdr): Only check on diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index b6271c469ef..e640e945613 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2012-01-17 Jakub Jelinek + + PR tree-optimization/51877 + * gcc.c-torture/execute/pr51877.c: New test. + 2012-01-17 Michael Zolotukhin * gcc.dg/vect/no-section-anchors-vect-69.c: Change diff --git a/gcc/testsuite/gcc.c-torture/execute/pr51877.c b/gcc/testsuite/gcc.c-torture/execute/pr51877.c new file mode 100644 index 00000000000..a2d65cfd9d8 --- /dev/null +++ b/gcc/testsuite/gcc.c-torture/execute/pr51877.c @@ -0,0 +1,50 @@ +/* PR tree-optimization/51877 */ + +extern void abort (void); +struct A { int a; char b[32]; } a, b; + +__attribute__((noinline, noclone)) +struct A +bar (int x) +{ + struct A r; + static int n; + r.a = ++n; + __builtin_memset (r.b, 0, sizeof (r.b)); + r.b[0] = x; + return r; +} + +__attribute__((noinline, noclone)) +void +baz (void) +{ + asm volatile ("" : : : "memory"); +} + +__attribute__((noinline, noclone)) +void +foo (struct A *x, int y) +{ + if (y == 6) + a = bar (7); + else + *x = bar (7); + baz (); +} + +int +main () +{ + a = bar (3); + b = bar (4); + if (a.a != 1 || a.b[0] != 3 || b.a != 2 || b.b[0] != 4) + abort (); + foo (&b, 0); + if (a.a != 1 || a.b[0] != 3 || b.a != 3 || b.b[0] != 7) + abort (); + foo (&b, 6); + if (a.a != 4 || a.b[0] != 7 || b.a != 3 || b.b[0] != 7) + abort (); + return 0; +} diff --git a/gcc/tree-ssa-tail-merge.c b/gcc/tree-ssa-tail-merge.c index 7452266af2b..47dc0a6ffc8 100644 --- a/gcc/tree-ssa-tail-merge.c +++ b/gcc/tree-ssa-tail-merge.c @@ -1,5 +1,5 @@ /* Tail merging for gimple. - Copyright (C) 2011 Free Software Foundation, Inc. + Copyright (C) 2011, 2012 Free Software Foundation, Inc. Contributed by Tom de Vries (tom@codesourcery.com) This file is part of GCC. @@ -1071,14 +1071,18 @@ gimple_equal_p (same_succ same_succ, gimple s1, gimple s2) equal = false; break; } - if (equal) - return true; + if (!equal) + return false; lhs1 = gimple_get_lhs (s1); lhs2 = gimple_get_lhs (s2); - return (lhs1 != NULL_TREE && lhs2 != NULL_TREE - && TREE_CODE (lhs1) == SSA_NAME && TREE_CODE (lhs2) == SSA_NAME - && vn_valueize (lhs1) == vn_valueize (lhs2)); + if (lhs1 == NULL_TREE && lhs2 == NULL_TREE) + return true; + if (lhs1 == NULL_TREE || lhs2 == NULL_TREE) + return false; + if (TREE_CODE (lhs1) == SSA_NAME && TREE_CODE (lhs2) == SSA_NAME) + return vn_valueize (lhs1) == vn_valueize (lhs2); + return operand_equal_p (lhs1, lhs2, 0); case GIMPLE_ASSIGN: lhs1 = gimple_get_lhs (s1); -- 2.11.0