diff options
Diffstat (limited to 'gcc/fold-const.c')
| -rw-r--r-- | gcc/fold-const.c | 33 |
1 files changed, 14 insertions, 19 deletions
diff --git a/gcc/fold-const.c b/gcc/fold-const.c index a67c34d4d39..831aaba683c 100644 --- a/gcc/fold-const.c +++ b/gcc/fold-const.c @@ -11334,7 +11334,6 @@ fold_binary_loc (location_t loc, && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST) { int width = TYPE_PRECISION (type), w; - bool try_simplify = true; wide_int c1 = TREE_OPERAND (arg0, 1); wide_int c2 = arg1; @@ -11368,20 +11367,7 @@ fold_binary_loc (location_t loc, } } - /* If X is a tree of the form (Y * K1) & K2, this might conflict - with that optimization from the BIT_AND_EXPR optimizations. - This could end up in an infinite recursion. */ - if (TREE_CODE (TREE_OPERAND (arg0, 0)) == MULT_EXPR - && TREE_CODE (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1)) - == INTEGER_CST) - { - tree t = TREE_OPERAND (TREE_OPERAND (arg0, 0), 1); - wide_int masked = mask_with_tz (type, c3, t); - - try_simplify = (masked != c1); - } - - if (try_simplify && c3 != c1) + if (c3 != c1) return fold_build2_loc (loc, BIT_IOR_EXPR, type, fold_build2_loc (loc, BIT_AND_EXPR, type, TREE_OPERAND (arg0, 0), @@ -11770,14 +11756,23 @@ fold_binary_loc (location_t loc, && TREE_CODE (arg0) == MULT_EXPR && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST) { - wide_int masked = mask_with_tz (type, arg1, TREE_OPERAND (arg0, 1)); + wide_int warg1 = arg1; + wide_int masked = mask_with_tz (type, warg1, TREE_OPERAND (arg0, 1)); if (masked == 0) return omit_two_operands_loc (loc, type, build_zero_cst (type), arg0, arg1); - else if (masked != arg1) - return fold_build2_loc (loc, code, type, op0, - wide_int_to_tree (type, masked)); + else if (masked != warg1) + { + /* Avoid the transform if arg1 is a mask of some + mode which allows further optimizations. */ + int pop = wi::popcount (warg1); + if (!(pop >= BITS_PER_UNIT + && exact_log2 (pop) != -1 + && wi::mask (pop, false, warg1.get_precision ()) == warg1)) + return fold_build2_loc (loc, code, type, op0, + wide_int_to_tree (type, masked)); + } } /* For constants M and N, if M == (1LL << cst) - 1 && (N & M) == M, |