LLVM OpenMP* Runtime Library
kmp_wrapper_malloc.h
1 /*
2  * kmp_wrapper_malloc.h -- Wrappers for memory allocation routines
3  * (malloc(), free(), and others).
4  */
5 
6 //===----------------------------------------------------------------------===//
7 //
8 // The LLVM Compiler Infrastructure
9 //
10 // This file is dual licensed under the MIT and the University of Illinois Open
11 // Source Licenses. See LICENSE.txt for details.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #ifndef KMP_WRAPPER_MALLOC_H
16 #define KMP_WRAPPER_MALLOC_H
17 
18 /* This header serves for 3 purposes:
19  1. Declaring standard memory allocation rourines in OS-independent way.
20  2. Passing source location info through memory allocation wrappers.
21  3. Enabling native memory debugging capabilities.
22 
23  1. Declaring standard memory allocation rourines in OS-independent way.
24  -----------------------------------------------------------------------
25  On Linux* OS, alloca() function is declared in <alloca.h> header, while on
26  Windows* OS there is no <alloca.h> header, function _alloca() (note
27  underscore!) is declared in <malloc.h>. This header eliminates these
28  differences, so client code incluiding "kmp_wrapper_malloc.h" can rely on
29  following routines:
30 
31  malloc
32  calloc
33  realloc
34  free
35  alloca
36 
37  in OS-independent way. It also enables memory tracking capabilities in debug
38  build. (Currently it is available only on Windows* OS.)
39 
40  2. Passing source location info through memory allocation wrappers.
41  -------------------------------------------------------------------
42  Some tools may help debugging memory errors, for example, report memory
43  leaks. However, memory allocation wrappers may hinder source location.
44  For example:
45 
46  void * aligned_malloc( int size ) {
47  void * ptr = malloc( size ); // All the memory leaks will be reported at
48  // this line.
49  // some adjustments...
50  return ptr;
51  };
52 
53  ptr = aligned_malloc( size ); // Memory leak will *not* be detected here. :-(
54 
55  To overcome the problem, information about original source location should
56  be passed through all the memory allocation wrappers, for example:
57 
58  void * aligned_malloc( int size, char const * file, int line ) {
59  void * ptr = _malloc_dbg( size, file, line );
60  // some adjustments...
61  return ptr;
62  };
63  void * ptr = aligned_malloc( size, __FILE__, __LINE__ );
64 
65  This is a good idea for debug, but passing additional arguments impacts
66  performance. Disabling extra arguments in release version of the software
67  introduces too many conditional compilation, which makes code unreadable.
68  This header defines few macros and functions facilitating it:
69 
70  void * _aligned_malloc( int size KMP_SRC_LOC_DECL ) {
71  void * ptr = malloc_src_loc( size KMP_SRC_LOC_PARM );
72  // some adjustments...
73  return ptr;
74  };
75  #define aligned_malloc( size ) _aligned_malloc( (size) KMP_SRC_LOC_CURR )
76  // Use macro instead of direct call to function.
77 
78  void * ptr = aligned_malloc( size ); // Bingo! Memory leak will be
79  // reported at this line.
80 
81  3. Enabling native memory debugging capabilities.
82  -------------------------------------------------
83  Some platforms may offer memory debugging capabilities. For example, debug
84  version of Microsoft RTL tracks all memory allocations and can report memory
85  leaks. This header enables this, and makes report more useful (see "Passing
86  source location info through memory allocation wrappers").
87 */
88 
89 #include <stdlib.h>
90 
91 #include "kmp_os.h"
92 
93 // Include alloca() declaration.
94 #if KMP_OS_WINDOWS
95 #include <malloc.h> // Windows* OS: _alloca() declared in "malloc.h".
96 #if KMP_MSVC_COMPAT
97 #define alloca _alloca // Allow to use alloca() with no underscore.
98 #endif
99 #elif KMP_OS_DRAGONFLY || KMP_OS_FREEBSD || KMP_OS_NETBSD || KMP_OS_OPENBSD
100 // Declared in "stdlib.h".
101 #elif KMP_OS_UNIX
102 #include <alloca.h> // Linux* OS and OS X*: alloc() declared in "alloca".
103 #else
104 #error Unknown or unsupported OS.
105 #endif
106 
107 /* KMP_SRC_LOC_DECL -- Declaring source location paramemters, to be used in
108  function declaration.
109  KMP_SRC_LOC_PARM -- Source location paramemters, to be used to pass
110  parameters to underlying levels.
111  KMP_SRC_LOC_CURR -- Source location arguments describing current location,
112  to be used at top-level.
113 
114  Typical usage:
115  void * _aligned_malloc( int size KMP_SRC_LOC_DECL ) {
116  // Note: Comma is missed before KMP_SRC_LOC_DECL.
117  KE_TRACE( 25, ( "called from %s:%d\n", KMP_SRC_LOC_PARM ) );
118  ...
119  }
120  #define aligned_malloc( size ) _aligned_malloc( (size) KMP_SRC_LOC_CURR )
121  // Use macro instead of direct call to function -- macro passes info
122  // about current source location to the func.
123 */
124 #if KMP_DEBUG
125 #define KMP_SRC_LOC_DECL , char const *_file_, int _line_
126 #define KMP_SRC_LOC_PARM , _file_, _line_
127 #define KMP_SRC_LOC_CURR , __FILE__, __LINE__
128 #else
129 #define KMP_SRC_LOC_DECL
130 #define KMP_SRC_LOC_PARM
131 #define KMP_SRC_LOC_CURR
132 #endif // KMP_DEBUG
133 
134 /* malloc_src_loc() and free_src_loc() are pseudo-functions (really macros)
135  with accepts extra arguments (source location info) in debug mode. They
136  should be used in place of malloc() and free(), this allows enabling native
137  memory debugging capabilities (if any).
138 
139  Typical usage:
140  ptr = malloc_src_loc( size KMP_SRC_LOC_PARM );
141  // Inside memory allocation wrapper, or
142  ptr = malloc_src_loc( size KMP_SRC_LOC_CURR );
143  // Outside of memory allocation wrapper.
144 */
145 #define malloc_src_loc(args) _malloc_src_loc(args)
146 #define free_src_loc(args) _free_src_loc(args)
147 /* Depending on build mode (debug or release), malloc_src_loc is declared with
148  1 or 3 parameters, but calls to malloc_src_loc() are always the same:
149 
150  ... malloc_src_loc( size KMP_SRC_LOC_PARM ); // or KMP_SRC_LOC_CURR
151 
152  Compiler issues warning/error "too few arguments in macro invocation".
153  Declaring two macros, malloc_src_loc() and _malloc_src_loc(), overcomes the
154  problem. */
155 
156 #if KMP_DEBUG
157 
158 #if KMP_OS_WINDOWS && _DEBUG
159 // KMP_DEBUG != _DEBUG. MS debug RTL is available only if _DEBUG is defined.
160 
161 // Windows* OS has native memory debugging capabilities. Enable them.
162 
163 #include <crtdbg.h>
164 
165 #define KMP_MEM_BLOCK _CLIENT_BLOCK
166 #define malloc(size) _malloc_dbg((size), KMP_MEM_BLOCK, __FILE__, __LINE__)
167 #define calloc(num, size) \
168  _calloc_dbg((num), (size), KMP_MEM_BLOCK, __FILE__, __LINE__)
169 #define realloc(ptr, size) \
170  _realloc_dbg((ptr), (size), KMP_MEM_BLOCK, __FILE__, __LINE__)
171 #define free(ptr) _free_dbg((ptr), KMP_MEM_BLOCK)
172 
173 #define _malloc_src_loc(size, file, line) \
174  _malloc_dbg((size), KMP_MEM_BLOCK, (file), (line))
175 #define _free_src_loc(ptr, file, line) _free_dbg((ptr), KMP_MEM_BLOCK)
176 
177 #else
178 
179 // Linux* OS, OS X*, or non-debug Windows* OS.
180 
181 #define _malloc_src_loc(size, file, line) malloc((size))
182 #define _free_src_loc(ptr, file, line) free((ptr))
183 
184 #endif
185 
186 #else
187 
188 // In release build malloc_src_loc() and free_src_loc() do not have extra
189 // parameters.
190 #define _malloc_src_loc(size) malloc((size))
191 #define _free_src_loc(ptr) free((ptr))
192 
193 #endif // KMP_DEBUG
194 
195 #endif // KMP_WRAPPER_MALLOC_H
196 
197 // end of file //