From 9095b53a8c4a5663b89db946462ff534fe0836e7 Mon Sep 17 00:00:00 2001 From: Jakub Jelinek Date: Wed, 12 Sep 2018 11:18:55 +0200 Subject: [PATCH] re PR middle-end/87248 (Bad code for masked operations involving signed ints) PR middle-end/87248 * fold-const.c (fold_ternary_loc) : Verify also that BIT_AND_EXPR's second operand is a power of two. Formatting fix. * c-c++-common/torture/pr87248.c: New test. From-SVN: r264230 --- gcc/ChangeLog | 6 ++++ gcc/fold-const.c | 12 +++++-- gcc/testsuite/ChangeLog | 5 +++ gcc/testsuite/c-c++-common/torture/pr87248.c | 36 ++++++++++++++++++++ 4 files changed, 56 insertions(+), 3 deletions(-) create mode 100644 gcc/testsuite/c-c++-common/torture/pr87248.c diff --git a/gcc/ChangeLog b/gcc/ChangeLog index de60879ea6c..c08654dfe2b 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,9 @@ +2018-09-12 Jakub Jelinek + + PR middle-end/87248 + * fold-const.c (fold_ternary_loc) : Verify also that + BIT_AND_EXPR's second operand is a power of two. Formatting fix. + 2018-09-12 Tom de Vries * common.opt (gdescribe-dies): Add option. diff --git a/gcc/fold-const.c b/gcc/fold-const.c index bdd24c5969b..3bcf272bd63 100644 --- a/gcc/fold-const.c +++ b/gcc/fold-const.c @@ -11607,10 +11607,16 @@ fold_ternary_loc (location_t loc, enum tree_code code, tree type, && integer_pow2p (arg1) && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_AND_EXPR && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1), - arg1, OEP_ONLY_CONST)) + arg1, OEP_ONLY_CONST) + /* operand_equal_p compares just value, not precision, so e.g. + arg1 could be 8-bit -128 and be power of two, but BIT_AND_EXPR + second operand 32-bit -128, which is not a power of two (or vice + versa. */ + && integer_pow2p (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1))) return pedantic_non_lvalue_loc (loc, - fold_convert_loc (loc, type, - TREE_OPERAND (arg0, 0))); + fold_convert_loc (loc, type, + TREE_OPERAND (arg0, + 0))); /* Disable the transformations below for vectors, since fold_binary_op_with_conditional_arg may undo them immediately, diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index a429bc3d8b9..c32dc771486 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2018-09-12 Jakub Jelinek + + PR middle-end/87248 + * c-c++-common/torture/pr87248.c: New test. + 2018-09-11 Janus Weil PR fortran/87172 diff --git a/gcc/testsuite/c-c++-common/torture/pr87248.c b/gcc/testsuite/c-c++-common/torture/pr87248.c new file mode 100644 index 00000000000..6f89bc9a31c --- /dev/null +++ b/gcc/testsuite/c-c++-common/torture/pr87248.c @@ -0,0 +1,36 @@ +/* PR middle-end/87248 */ +/* { dg-do run } */ + +void +foo (signed char *p, int q) +{ + *p = q & (-__SCHAR_MAX__ - 1) ? (-__SCHAR_MAX__ - 1) : 0; +} + +int +bar (long long x) +{ + return x & (-__INT_MAX__ - 1) ? (-__INT_MAX__ - 1) : 0; +} + +int +main () +{ +#if __INT_MAX__ > 4 * __SCHAR_MAX__ + signed char a[4]; + foo (a, __SCHAR_MAX__ + 1U); + foo (a + 1, 2 * (__SCHAR_MAX__ + 1U)); + foo (a + 2, -__INT_MAX__ - 1); + foo (a + 3, (__SCHAR_MAX__ + 1U) / 2); + if (a[0] != (-__SCHAR_MAX__ - 1) || a[1] != a[0] || a[2] != a[0] || a[3] != 0) + __builtin_abort (); +#endif +#if __LONG_LONG_MAX__ > 4 * __INT_MAX__ + if (bar (__INT_MAX__ + 1LL) != (-__INT_MAX__ - 1) + || bar (2 * (__INT_MAX__ + 1LL)) != (-__INT_MAX__ - 1) + || bar (-__LONG_LONG_MAX__ - 1) != (-__INT_MAX__ - 1) + || bar ((__INT_MAX__ + 1LL) / 2) != 0) + __builtin_abort (); +#endif + return 0; +} -- 2.30.2