From 90b56f40c147d5eff51e79d8d673d539c845a4d1 Mon Sep 17 00:00:00 2001 From: rakdver Date: Wed, 22 Nov 2006 23:11:15 +0000 Subject: [PATCH] PR tree-optimization/29921 * fold-const.c (operand_equal_p): Without HONOR_SIGNED_ZEROS, consider signed and unsigned zero equal. * gcc.dg/pr29921.c: New test. git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@119102 138bc75d-0d04-0410-961f-82ee72b054a4 --- gcc/ChangeLog | 6 ++++++ gcc/fold-const.c | 15 +++++++++++++-- gcc/testsuite/ChangeLog | 5 +++++ gcc/testsuite/gcc.dg/pr29921.c | 20 ++++++++++++++++++++ 4 files changed, 44 insertions(+), 2 deletions(-) create mode 100644 gcc/testsuite/gcc.dg/pr29921.c diff --git a/gcc/ChangeLog b/gcc/ChangeLog index c6fdb9f1830..5bb0ce3bfc6 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,9 @@ +2006-11-23 Zdenek Dvorak + + PR tree-optimization/29921 + * fold-const.c (operand_equal_p): Without HONOR_SIGNED_ZEROS, consider + signed and unsigned zero equal. + 2006-11-22 Peter Bergner * config/rs6000/rs6000.c (get_store_dest): New. diff --git a/gcc/fold-const.c b/gcc/fold-const.c index cd7f1d9e831..b19b7688a2d 100644 --- a/gcc/fold-const.c +++ b/gcc/fold-const.c @@ -2584,8 +2584,19 @@ operand_equal_p (tree arg0, tree arg1, unsigned int flags) return tree_int_cst_equal (arg0, arg1); case REAL_CST: - return REAL_VALUES_IDENTICAL (TREE_REAL_CST (arg0), - TREE_REAL_CST (arg1)); + if (REAL_VALUES_IDENTICAL (TREE_REAL_CST (arg0), + TREE_REAL_CST (arg1))) + return 1; + + + if (!HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))) + { + /* If we do not distinguish between signed and unsigned zero, + consider them equal. */ + if (real_zerop (arg0) && real_zerop (arg1)) + return 1; + } + return 0; case VECTOR_CST: { diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index ff2a80dad5b..f8dc647d4e0 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2006-11-23 Zdenek Dvorak + + PR tree-optimization/29921 + * gcc.dg/pr29921.c: New test. + 2006-11-22 Tobias Schlueter PR fortran/29441 diff --git a/gcc/testsuite/gcc.dg/pr29921.c b/gcc/testsuite/gcc.dg/pr29921.c new file mode 100644 index 00000000000..7689f54ce25 --- /dev/null +++ b/gcc/testsuite/gcc.dg/pr29921.c @@ -0,0 +1,20 @@ +/* With -ffast-math, the latice value for t changes from -0.0 to 0.0 in this + testcase. */ + +/* { dg-do compile } */ +/* { dg-options "-O2 -ffast-math" } */ + +double test (int param) +{ + double a = 0.0, b = -1.0, t; + int i; + + for (i = 0; i < 100; i++) + { + t = a * b; + if (param) + b = 2.0; + } + + return t; +} -- 2.11.4.GIT