1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
|
/* -Wnonnull-compare warning support.
Copyright (C) 2016-2019 Free Software Foundation, Inc.
Contributed by Jakub Jelinek <jakub@redhat.com>
This file is part of GCC.
GCC is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3, or (at your option)
any later version.
GCC is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with GCC; see the file COPYING3. If not see
<http://www.gnu.org/licenses/>. */
#include "config.h"
#include "system.h"
#include "coretypes.h"
#include "backend.h"
#include "tree.h"
#include "gimple.h"
#include "tree-pass.h"
#include "ssa.h"
#include "diagnostic-core.h"
#include "tree-dfa.h"
/* Warn about comparison of nonnull_arg_p argument initial values
with NULL. */
static void
do_warn_nonnull_compare (function *fun, tree arg)
{
if (!POINTER_TYPE_P (TREE_TYPE (arg))
&& TREE_CODE (TREE_TYPE (arg)) != OFFSET_TYPE)
return;
if (!nonnull_arg_p (arg))
return;
tree d = ssa_default_def (fun, arg);
if (d == NULL_TREE)
return;
use_operand_p use_p;
imm_use_iterator iter;
FOR_EACH_IMM_USE_FAST (use_p, iter, d)
{
gimple *stmt = USE_STMT (use_p);
tree op = NULL_TREE;
location_t loc = gimple_location (stmt);
if (gimple_code (stmt) == GIMPLE_COND)
switch (gimple_cond_code (stmt))
{
case EQ_EXPR:
case NE_EXPR:
if (gimple_cond_lhs (stmt) == d)
op = gimple_cond_rhs (stmt);
break;
default:
break;
}
else if (is_gimple_assign (stmt))
switch (gimple_assign_rhs_code (stmt))
{
case EQ_EXPR:
case NE_EXPR:
if (gimple_assign_rhs1 (stmt) == d)
op = gimple_assign_rhs2 (stmt);
break;
case COND_EXPR:
switch (TREE_CODE (gimple_assign_rhs1 (stmt)))
{
case EQ_EXPR:
case NE_EXPR:
op = gimple_assign_rhs1 (stmt);
if (TREE_OPERAND (op, 0) != d)
{
op = NULL_TREE;
break;
}
loc = EXPR_LOC_OR_LOC (op, loc);
op = TREE_OPERAND (op, 1);
break;
default:
break;
}
break;
default:
break;
}
if (op
&& (POINTER_TYPE_P (TREE_TYPE (arg))
? integer_zerop (op) : integer_minus_onep (op))
&& !gimple_no_warning_p (stmt))
warning_at (loc, OPT_Wnonnull_compare,
"%<nonnull%> argument %qD compared to NULL", arg);
}
}
namespace {
const pass_data pass_data_warn_nonnull_compare =
{
GIMPLE_PASS, /* type */
"*nonnullcmp", /* name */
OPTGROUP_NONE, /* optinfo_flags */
TV_NONE, /* tv_id */
PROP_ssa, /* properties_required */
0, /* properties_provided */
0, /* properties_destroyed */
0, /* todo_flags_start */
0, /* todo_flags_finish */
};
class pass_warn_nonnull_compare : public gimple_opt_pass
{
public:
pass_warn_nonnull_compare (gcc::context *ctxt)
: gimple_opt_pass (pass_data_warn_nonnull_compare, ctxt)
{}
/* opt_pass methods: */
virtual bool gate (function *) { return warn_nonnull_compare; }
virtual unsigned int execute (function *);
}; // class pass_warn_nonnull_compare
unsigned int
pass_warn_nonnull_compare::execute (function *fun)
{
if (fun->static_chain_decl)
do_warn_nonnull_compare (fun, fun->static_chain_decl);
for (tree arg = DECL_ARGUMENTS (cfun->decl); arg; arg = DECL_CHAIN (arg))
do_warn_nonnull_compare (fun, arg);
return 0;
}
} // anon namespace
gimple_opt_pass *
make_pass_warn_nonnull_compare (gcc::context *ctxt)
{
return new pass_warn_nonnull_compare (ctxt);
}
|
