1 /* 2 * Copyright (C) 2012 Oracle. 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public License 6 * as published by the Free Software Foundation; either version 2 7 * of the License, or (at your option) any later version. 8 * 9 * This program is distributed in the hope that it will be useful, 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 * GNU General Public License for more details. 13 * 14 * You should have received a copy of the GNU General Public License 15 * along with this program; if not, see http://www.gnu.org/copyleft/gpl.txt 16 */ 17 18 #include "smatch.h" 19 20 static int my_id; 21 22 static void match_shift_assignment(struct expression *expr) 23 { 24 struct symbol *left_type, *right_type; 25 struct expression *right; 26 sval_t sval; 27 sval_t bits, shifter; 28 char *name; 29 30 right = strip_expr(expr->right); 31 if (right->type != EXPR_BINOP || right->op != SPECIAL_LEFTSHIFT) 32 return; 33 34 left_type = get_type(expr->left); 35 if (left_type != &llong_ctype && left_type != &ullong_ctype) 36 return; 37 38 right_type = get_type(expr->right); 39 40 if (type_bits(right_type) == 64) 41 return; 42 43 if (get_value(right, &sval)) 44 return; 45 46 get_absolute_max(right->left, &bits); 47 get_absolute_max(right->right, &shifter); 48 49 bits = sval_cast(&ullong_ctype, bits); 50 if (sval_cmp_val(shifter, 32) < 0) { 51 sval = sval_binop(bits, SPECIAL_LEFTSHIFT, shifter); 52 if (sval_cmp_val(sval, UINT_MAX) < 0) 53 return; 54 } 55 56 name = expr_to_str_sym(right, NULL); 57 sm_warning("should '%s' be a 64 bit type?", name); 58 free_string(name); 59 } 60 61 void check_64bit_shift(int id) 62 { 63 my_id = id; 64 65 add_hook(&match_shift_assignment, ASSIGNMENT_HOOK); 66 } 67