diff options
Diffstat (limited to 'gcc/fold-const.c')
| -rw-r--r-- | gcc/fold-const.c | 100 |
1 files changed, 0 insertions, 100 deletions
diff --git a/gcc/fold-const.c b/gcc/fold-const.c index 60aa210..6fa784a 100644 --- a/gcc/fold-const.c +++ b/gcc/fold-const.c @@ -11516,106 +11516,6 @@ fold_binary_loc (location_t loc, return build_int_cst (type, residue & low); } - /* Fold (X << C1) & C2 into (X << C1) & (C2 | ((1 << C1) - 1)) - (X >> C1) & C2 into (X >> C1) & (C2 | ~((type) -1 >> C1)) - if the new mask might be further optimized. */ - if ((TREE_CODE (arg0) == LSHIFT_EXPR - || TREE_CODE (arg0) == RSHIFT_EXPR) - && TYPE_PRECISION (TREE_TYPE (arg0)) <= HOST_BITS_PER_WIDE_INT - && TREE_CODE (arg1) == INTEGER_CST - && tree_fits_uhwi_p (TREE_OPERAND (arg0, 1)) - && tree_to_uhwi (TREE_OPERAND (arg0, 1)) > 0 - && (tree_to_uhwi (TREE_OPERAND (arg0, 1)) - < TYPE_PRECISION (TREE_TYPE (arg0)))) - { - unsigned int shiftc = tree_to_uhwi (TREE_OPERAND (arg0, 1)); - unsigned HOST_WIDE_INT mask = TREE_INT_CST_LOW (arg1); - unsigned HOST_WIDE_INT newmask, zerobits = 0; - tree shift_type = TREE_TYPE (arg0); - - if (TREE_CODE (arg0) == LSHIFT_EXPR) - zerobits = ((((unsigned HOST_WIDE_INT) 1) << shiftc) - 1); - else if (TREE_CODE (arg0) == RSHIFT_EXPR - && TYPE_PRECISION (TREE_TYPE (arg0)) - == GET_MODE_PRECISION (TYPE_MODE (TREE_TYPE (arg0)))) - { - prec = TYPE_PRECISION (TREE_TYPE (arg0)); - tree arg00 = TREE_OPERAND (arg0, 0); - /* See if more bits can be proven as zero because of - zero extension. */ - if (TREE_CODE (arg00) == NOP_EXPR - && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg00, 0)))) - { - tree inner_type = TREE_TYPE (TREE_OPERAND (arg00, 0)); - if (TYPE_PRECISION (inner_type) - == GET_MODE_PRECISION (TYPE_MODE (inner_type)) - && TYPE_PRECISION (inner_type) < prec) - { - prec = TYPE_PRECISION (inner_type); - /* See if we can shorten the right shift. */ - if (shiftc < prec) - shift_type = inner_type; - /* Otherwise X >> C1 is all zeros, so we'll optimize - it into (X, 0) later on by making sure zerobits - is all ones. */ - } - } - zerobits = ~(unsigned HOST_WIDE_INT) 0; - if (shiftc < prec) - { - zerobits >>= HOST_BITS_PER_WIDE_INT - shiftc; - zerobits <<= prec - shiftc; - } - /* For arithmetic shift if sign bit could be set, zerobits - can contain actually sign bits, so no transformation is - possible, unless MASK masks them all away. In that - case the shift needs to be converted into logical shift. */ - if (!TYPE_UNSIGNED (TREE_TYPE (arg0)) - && prec == TYPE_PRECISION (TREE_TYPE (arg0))) - { - if ((mask & zerobits) == 0) - shift_type = unsigned_type_for (TREE_TYPE (arg0)); - else - zerobits = 0; - } - } - - /* ((X << 16) & 0xff00) is (X, 0). */ - if ((mask & zerobits) == mask) - return omit_one_operand_loc (loc, type, - build_int_cst (type, 0), arg0); - - newmask = mask | zerobits; - if (newmask != mask && (newmask & (newmask + 1)) == 0) - { - /* Only do the transformation if NEWMASK is some integer - mode's mask. */ - for (prec = BITS_PER_UNIT; - prec < HOST_BITS_PER_WIDE_INT; prec <<= 1) - if (newmask == (((unsigned HOST_WIDE_INT) 1) << prec) - 1) - break; - if (prec < HOST_BITS_PER_WIDE_INT - || newmask == ~(unsigned HOST_WIDE_INT) 0) - { - tree newmaskt; - - if (shift_type != TREE_TYPE (arg0)) - { - tem = fold_build2_loc (loc, TREE_CODE (arg0), shift_type, - fold_convert_loc (loc, shift_type, - TREE_OPERAND (arg0, 0)), - TREE_OPERAND (arg0, 1)); - tem = fold_convert_loc (loc, type, tem); - } - else - tem = op0; - newmaskt = build_int_cst_type (TREE_TYPE (op1), newmask); - if (!tree_int_cst_equal (newmaskt, arg1)) - return fold_build2_loc (loc, BIT_AND_EXPR, type, tem, newmaskt); - } - } - } - goto associate; case RDIV_EXPR: |