cprover
ansi_c_declaration.cpp
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1 /*******************************************************************\
2 
3 Module: ANSI-C Language Type Checking
4 
5 Author: Daniel Kroening, kroening@kroening.com
6 
7 \*******************************************************************/
8 
11 
12 #include "ansi_c_declaration.h"
13 
14 #include <ostream>
15 #include <cassert>
16 
17 #include <util/config.h>
18 #include <util/std_types.h>
19 #include <util/invariant.h>
20 
22 {
23  typet *p=static_cast<typet *>(&src);
24 
25  // walk down subtype until we hit symbol or "abstract"
26  while(true)
27  {
28  typet &t=*p;
29 
30  if(t.id()==ID_symbol)
31  {
32  set_base_name(t.get(ID_C_base_name));
34  t.make_nil();
35  break;
36  }
37  else if(t.id().empty() ||
38  t.is_nil())
39  {
41  }
42  else if(t.id()==ID_abstract)
43  {
44  t.make_nil();
45  break;
46  }
47  else if(t.id()==ID_merged_type)
48  {
49  // we always walk down the _last_ member of a merged type
50  assert(!t.subtypes().empty());
51  p=&(t.subtypes().back());
52  }
53  else
54  p=&t.subtype();
55  }
56 
57  type()=static_cast<const typet &>(src);
58  value().make_nil();
59 }
60 
61 void ansi_c_declarationt::output(std::ostream &out) const
62 {
63  out << "Flags:";
64  if(get_is_typedef())
65  out << " is_typedef";
67  out << " is_enum_constant";
68  if(get_is_static())
69  out << " is_static";
70  if(get_is_parameter())
71  out << " is_parameter";
72  if(get_is_global())
73  out << " is_global";
74  if(get_is_register())
75  out << " is_register";
77  out << " is_thread_local";
78  if(get_is_inline())
79  out << " is_inline";
80  if(get_is_extern())
81  out << " is_extern";
83  out << " is_static_assert";
85  out << " is_always_inline";
86  out << "\n";
87 
88  out << "Type: " << type().pretty() << "\n";
89 
90  for(const auto &declarator : declarators())
91  out << "Declarator: " << declarator.pretty() << "\n";
92 }
93 
95  const ansi_c_declaratort &declarator) const
96 {
97  typet result=declarator.type();
98  typet *p=&result;
99 
100  // this gets types that are still raw parse trees
101  while(p->is_not_nil())
102  {
103  if(p->id()==ID_frontend_pointer || p->id()==ID_array ||
104  p->id()==ID_vector || p->id()==ID_c_bit_field ||
105  p->id()==ID_block_pointer || p->id()==ID_code)
106  p=&p->subtype();
107  else if(p->id()==ID_merged_type)
108  {
109  // we always go down on the right-most subtype
110  assert(!p->subtypes().empty());
111  p=&(p->subtypes().back());
112  }
113  else
114  UNREACHABLE;
115  }
116 
117  *p=type();
118 
119  // retain typedef for dump-c
120  if(get_is_typedef())
121  result.set(ID_C_typedef, declarator.get_name());
122 
123  return result;
124 }
125 
127  const ansi_c_declaratort &declarator,
128  symbolt &symbol) const
129 {
130  symbol.clear();
131  symbol.value=declarator.value();
132  symbol.type=full_type(declarator);
133  symbol.name=declarator.get_name();
134  symbol.pretty_name=symbol.name;
136  symbol.is_type=get_is_typedef();
138  symbol.is_extern=get_is_extern();
141  symbol.is_weak=get_is_weak();
142 
143  // is it a function?
144 
145  if(symbol.type.id()==ID_code && !symbol.is_type)
146  {
147  symbol.is_static_lifetime=false;
148  symbol.is_thread_local=false;
149 
150  symbol.is_file_local=get_is_static();
151 
152  if(get_is_inline())
153  symbol.type.set(ID_C_inlined, true);
154 
158  {
159  // GCC extern inline cleanup, to enable remove_internal_symbols
160  // do its full job
161  // https://gcc.gnu.org/ml/gcc/2006-11/msg00006.html
162  // __attribute__((__gnu_inline__))
163  if(get_is_inline())
164  {
165  if(get_is_static()) // C99 and above
166  symbol.is_extern=false;
167  else if(get_is_extern()) // traditional GCC
168  symbol.is_file_local=true;
169 
171  symbol.is_macro = true;
172  }
173 
174  // GCC __attribute__((__used__)) - do not treat those as file-local
175  if(get_is_used())
176  symbol.is_file_local = false;
177  }
178  }
179  else // non-function
180  {
181  symbol.is_static_lifetime=
182  !symbol.is_macro &&
183  !symbol.is_type &&
184  (get_is_global() || get_is_static());
185 
186  symbol.is_thread_local=
187  (!symbol.is_static_lifetime && !get_is_extern()) ||
189 
190  symbol.is_file_local=
191  symbol.is_macro ||
192  (!get_is_global() && !get_is_extern()) ||
193  (get_is_global() && get_is_static() && !get_is_used()) ||
194  symbol.is_parameter;
195  }
196 }
bool get_is_static_assert() const
The type of an expression.
Definition: type.h:22
irep_idt name
The unique identifier.
Definition: symbol.h:43
bool get_is_static() const
struct configt::ansi_ct ansi_c
bool get_is_register() const
bool is_nil() const
Definition: irep.h:102
bool is_not_nil() const
Definition: irep.h:103
bool is_thread_local
Definition: symbol.h:67
std::string pretty(unsigned indent=0, unsigned max_indent=0) const
Definition: irep.cpp:641
bool get_is_typedef() const
void clear()
Definition: symbol.h:76
void build(irept &src)
subtypest & subtypes()
Definition: type.h:58
exprt value
Initial value of symbol.
Definition: symbol.h:37
void to_symbol(const ansi_c_declaratort &, symbolt &symbol) const
irep_idt pretty_name
Language-specific display name.
Definition: symbol.h:55
typet & type()
Definition: expr.h:56
Symbol table entry.This is a symbol in the symbol table, stored in an object of type symbol_tablet...
Definition: symbol.h:30
configt config
Definition: config.cpp:23
typet full_type(const ansi_c_declaratort &) const
bool is_static_lifetime
Definition: symbol.h:67
const irep_idt & id() const
Definition: irep.h:189
const declaratorst & declarators() const
irep_idt get_base_name() const
void set_base_name(const irep_idt &base_name)
flavourt mode
Definition: config.h:106
bool is_parameter
Definition: symbol.h:68
bool get_is_enum_constant() const
const irep_idt & get(const irep_namet &name) const
Definition: irep.cpp:213
irep_idt get_name() const
Base class for tree-like data structures with sharing.
Definition: irep.h:86
bool get_is_always_inline() const
const source_locationt & source_location() const
Definition: type.h:97
void output(std::ostream &) const
bool is_extern
Definition: symbol.h:68
typet type
Type of symbol.
Definition: symbol.h:34
source_locationt location
Source code location of definition of symbol.
Definition: symbol.h:40
API to type classes.
bool get_is_parameter() const
irep_idt base_name
Base (non-scoped) name.
Definition: symbol.h:49
const source_locationt & source_location() const
Definition: expr.h:125
#define UNREACHABLE
Definition: invariant.h:250
bool is_file_local
Definition: symbol.h:68
ANSI-CC Language Type Checking.
void make_nil()
Definition: irep.h:243
bool is_weak
Definition: symbol.h:68
source_locationt & add_source_location()
Definition: expr.h:130
bool is_type
Definition: symbol.h:63
const typet & subtype() const
Definition: type.h:33
bool empty() const
Definition: dstring.h:61
bool is_macro
Definition: symbol.h:63
void set(const irep_namet &name, const irep_idt &value)
Definition: irep.h:214
bool get_is_thread_local() const
const ansi_c_declaratort & declarator() const