From 81ad578ea1b8fbeafe172152cc27c0f4911502ce Mon Sep 17 00:00:00 2001 From: Richard Guenther Date: Tue, 29 Apr 2008 13:52:53 +0000 Subject: [PATCH] re PR middle-end/36077 (Expressions result is wrong) 2008-04-29 Richard Guenther PR middle-end/36077 * fold-const.c (extract_muldiv_1): In combining division constants make sure to never overflow. * gcc.c-torture/execute/pr36077.c: New testcase. From-SVN: r134792 --- gcc/ChangeLog | 6 ++++++ gcc/fold-const.c | 9 +++++++-- gcc/testsuite/ChangeLog | 5 +++++ gcc/testsuite/gcc.c-torture/execute/pr36077.c | 13 +++++++++++++ 4 files changed, 31 insertions(+), 2 deletions(-) create mode 100644 gcc/testsuite/gcc.c-torture/execute/pr36077.c diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 1c7cba1c568..3ffe3bc08f3 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,9 @@ +2008-04-29 Richard Guenther + + PR middle-end/36077 + * fold-const.c (extract_muldiv_1): In combining division constants + make sure to never overflow. + 2008-04-29 Nick Clifton * doc/tm.texi (RETURN_ADDR_RTX): Fix typo. diff --git a/gcc/fold-const.c b/gcc/fold-const.c index a4d5760b861..aae20377728 100644 --- a/gcc/fold-const.c +++ b/gcc/fold-const.c @@ -5953,8 +5953,13 @@ extract_muldiv_1 (tree t, tree c, enum tree_code code, tree wide_type, /* If these are the same operation types, we can associate them assuming no overflow. */ if (tcode == code - && 0 != (t1 = const_binop (MULT_EXPR, fold_convert (ctype, op1), - fold_convert (ctype, c), 0)) + && 0 != (t1 = int_const_binop (MULT_EXPR, fold_convert (ctype, op1), + fold_convert (ctype, c), 1)) + && 0 != (t1 = force_fit_type_double (ctype, TREE_INT_CST_LOW (t1), + TREE_INT_CST_HIGH (t1), + (TYPE_UNSIGNED (ctype) + && tcode != MULT_EXPR) ? -1 : 1, + TREE_OVERFLOW (t1))) && !TREE_OVERFLOW (t1)) return fold_build2 (tcode, ctype, fold_convert (ctype, op0), t1); diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index f6bb5e1aadc..f2b69e90afc 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2008-04-29 Richard Guenther + + PR middle-end/36077 + * gcc.c-torture/execute/pr36077.c: New testcase. + 2008-04-29 Kai Tietz * testsuite/gcc.dg/sync-2.c: Set dg-options "-ansi". diff --git a/gcc/testsuite/gcc.c-torture/execute/pr36077.c b/gcc/testsuite/gcc.c-torture/execute/pr36077.c new file mode 100644 index 00000000000..09636a10286 --- /dev/null +++ b/gcc/testsuite/gcc.c-torture/execute/pr36077.c @@ -0,0 +1,13 @@ +extern void abort (void); + +unsigned int test (unsigned int x) +{ + return x / 0x80000001U / 0x00000002U; +} + +int main() +{ + if (test(2) != 0) + abort (); + return 0; +} -- 2.30.2