check_precedence.c

   1 /*
   2  * sparse/check_precedence.c
   3  *
   4  * Copyright (C) 2010 Dan Carpenter.
   5  *
   6  * Licensed under the Open Software License version 1.1
   7  *
   8  */
   9
  10 #include "smatch.h"
  11
  12 static int my_id;
  13
  14 static int is_bool(struct expression *expr)
  15 {
  16         struct symbol *type;
  17
  18         type = get_type(expr);
  19         if (!type)
  20                 return 0;
  21         if (type->bit_size == 1 && type->ctype.modifiers & MOD_UNSIGNED)
  22                 return 1;
  23         return 0;
  24 }
  25
  26 static void match_condition(struct expression *expr)
  27 {
  28         int print = 0;
  29
  30         if (expr->type == EXPR_COMPARE) {
  31                 if (expr->left->type == EXPR_COMPARE || expr->right->type == EXPR_COMPARE)
  32                         print = 1;
  33                 if (expr->left->op == '!') {
  34                         if (expr->left->type == EXPR_PREOP && expr->left->unop->op == '!')
  35                                 return;
  36                         if (expr->right->op == '!')
  37                                 return;
  38                         if (is_bool(expr->right))
  39                                 return;
  40                         if (is_bool(expr->left->unop))
  41                                 return;
  42                         print = 1;
  43                 }
  44         }
  45
  46         if (expr->type == EXPR_BINOP) {
  47                 if (expr->left->type == EXPR_COMPARE || expr->right->type == EXPR_COMPARE)
  48                         print = 1;
  49         }
  50
  51         if (print)
  52                 sm_msg("warn: add some parenthesis here?");
  53 }
  54
  55 static void match_binop(struct expression *expr)
  56 {
  57         if (expr->op != '&')
  58                 return;
  59         if (expr->left->op == '!')
  60                 sm_msg("warn: add some parenthesis here?");
  61 }
  62
  63 void check_precedence(int id)
  64 {
  65         my_id = id;
  66
  67         add_hook(&match_condition, CONDITION_HOOK);
  68         add_hook(&match_binop, BINOP_HOOK);
  69 }