diff options
Diffstat (limited to 'gcc-4.9/gcc/tree-vrp.c')
-rw-r--r-- | gcc-4.9/gcc/tree-vrp.c | 57 |
1 files changed, 42 insertions, 15 deletions
diff --git a/gcc-4.9/gcc/tree-vrp.c b/gcc-4.9/gcc/tree-vrp.c index 306021062..14f1526fa 100644 --- a/gcc-4.9/gcc/tree-vrp.c +++ b/gcc-4.9/gcc/tree-vrp.c @@ -9336,31 +9336,58 @@ simplify_internal_call_using_ranges (gimple_stmt_iterator *gsi, gimple stmt) else if (TREE_CODE (op0) == INTEGER_CST) set_value_range_to_value (&vr0, op0, NULL); else - return false; + set_value_range_to_varying (&vr0); if (TREE_CODE (op1) == SSA_NAME) vr1 = *get_value_range (op1); else if (TREE_CODE (op1) == INTEGER_CST) set_value_range_to_value (&vr1, op1, NULL); else - return false; - - if (!range_int_cst_p (&vr0) || !range_int_cst_p (&vr1)) - return false; + set_value_range_to_varying (&vr1); - tree r1 = int_const_binop (subcode, vr0.min, vr1.min); - tree r2 = int_const_binop (subcode, vr0.max, vr1.max); - if (r1 == NULL_TREE || TREE_OVERFLOW (r1) - || r2 == NULL_TREE || TREE_OVERFLOW (r2)) - return false; - if (subcode == MULT_EXPR) + if (!range_int_cst_p (&vr0)) { - tree r3 = int_const_binop (subcode, vr0.min, vr1.max); - tree r4 = int_const_binop (subcode, vr0.max, vr1.min); - if (r3 == NULL_TREE || TREE_OVERFLOW (r3) - || r4 == NULL_TREE || TREE_OVERFLOW (r4)) + /* If one range is VR_ANTI_RANGE, VR_VARYING etc., + optimize at least x = y + 0; x = y - 0; x = y * 0; + and x = y * 1; which never overflow. */ + if (!range_int_cst_p (&vr1)) + return false; + if (tree_int_cst_sgn (vr1.min) == -1) + return false; + if (compare_tree_int (vr1.max, subcode == MULT_EXPR) == 1) return false; } + else if (!range_int_cst_p (&vr1)) + { + /* If one range is VR_ANTI_RANGE, VR_VARYING etc., + optimize at least x = 0 + y; x = 0 * y; and x = 1 * y; + which never overflow. */ + if (subcode == MINUS_EXPR) + return false; + if (!range_int_cst_p (&vr0)) + return false; + if (tree_int_cst_sgn (vr0.min) == -1) + return false; + if (compare_tree_int (vr0.max, subcode == MULT_EXPR) == 1) + return false; + } + else + { + tree r1 = int_const_binop (subcode, vr0.min, vr1.min); + tree r2 = int_const_binop (subcode, vr0.max, vr1.max); + if (r1 == NULL_TREE || TREE_OVERFLOW (r1) + || r2 == NULL_TREE || TREE_OVERFLOW (r2)) + return false; + if (subcode == MULT_EXPR) + { + tree r3 = int_const_binop (subcode, vr0.min, vr1.max); + tree r4 = int_const_binop (subcode, vr0.max, vr1.min); + if (r3 == NULL_TREE || TREE_OVERFLOW (r3) + || r4 == NULL_TREE || TREE_OVERFLOW (r4)) + return false; + } + } + gimple g = gimple_build_assign_with_ops (subcode, gimple_call_lhs (stmt), op0, op1); gsi_replace (gsi, g, false); |