1/*
2 * kmp_wrapper_malloc.h -- Wrappers for memory allocation routines
3 *                         (malloc(), free(), and others).
4 */
5
6//===----------------------------------------------------------------------===//
7//
8// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
9// See https://llvm.org/LICENSE.txt for license information.
10// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
11//
12//===----------------------------------------------------------------------===//
13
14#ifndef KMP_WRAPPER_MALLOC_H
15#define KMP_WRAPPER_MALLOC_H
16
17/* This header serves for 3 purposes:
18   1. Declaring standard memory allocation rourines in OS-independent way.
19   2. Passing source location info through memory allocation wrappers.
20   3. Enabling native memory debugging capabilities.
21
22   1. Declaring standard memory allocation rourines in OS-independent way.
23   -----------------------------------------------------------------------
24   On Linux* OS, alloca() function is declared in <alloca.h> header, while on
25   Windows* OS there is no <alloca.h> header, function _alloca() (note
26   underscore!) is declared in <malloc.h>. This header eliminates these
27   differences, so client code including "kmp_wrapper_malloc.h" can rely on
28   following routines:
29
30        malloc
31        calloc
32        realloc
33        free
34        alloca
35
36   in OS-independent way. It also enables memory tracking capabilities in debug
37   build. (Currently it is available only on Windows* OS.)
38
39   2. Passing source location info through memory allocation wrappers.
40   -------------------------------------------------------------------
41   Some tools may help debugging memory errors, for example, report memory
42   leaks. However, memory allocation wrappers may hinder source location.
43   For example:
44
45   void * aligned_malloc( int size ) {
46     void * ptr = malloc( size ); // All the memory leaks will be reported at
47                                  // this line.
48     // some adjustments...
49     return ptr;
50   };
51
52   ptr = aligned_malloc( size ); // Memory leak will *not* be detected here. :-(
53
54   To overcome the problem, information about original source location should
55   be passed through all the memory allocation wrappers, for example:
56
57   void * aligned_malloc( int size, char const * file, int line ) {
58     void * ptr = _malloc_dbg( size, file, line );
59     // some adjustments...
60     return ptr;
61   };
62   void * ptr = aligned_malloc( size, __FILE__, __LINE__ );
63
64   This is a good idea for debug, but passing additional arguments impacts
65   performance. Disabling extra arguments in release version of the software
66   introduces too many conditional compilation, which makes code unreadable.
67   This header defines few macros and functions facilitating it:
68
69   void * _aligned_malloc( int size KMP_SRC_LOC_DECL ) {
70     void * ptr = malloc_src_loc( size KMP_SRC_LOC_PARM );
71     // some adjustments...
72     return ptr;
73   };
74   #define aligned_malloc( size ) _aligned_malloc( (size) KMP_SRC_LOC_CURR )
75   // Use macro instead of direct call to function.
76
77   void * ptr = aligned_malloc( size );  // Bingo! Memory leak will be
78                                         // reported at this line.
79
80   3. Enabling native memory debugging capabilities.
81   -------------------------------------------------
82   Some platforms may offer memory debugging capabilities. For example, debug
83   version of Microsoft RTL tracks all memory allocations and can report memory
84   leaks. This header enables this, and makes report more useful (see "Passing
85   source location info through memory allocation wrappers").
86*/
87
88#include <stdlib.h>
89
90#include "kmp_os.h"
91
92// Include alloca() declaration.
93#if KMP_OS_WINDOWS
94#include <malloc.h> // Windows* OS: _alloca() declared in "malloc.h".
95#if KMP_MSVC_COMPAT
96#define alloca _alloca // Allow to use alloca() with no underscore.
97#endif
98#elif KMP_OS_DRAGONFLY || KMP_OS_FREEBSD || KMP_OS_NETBSD || KMP_OS_OPENBSD
99// Declared in "stdlib.h".
100#elif KMP_OS_UNIX
101#include <alloca.h> // Linux* OS and OS X*: alloc() declared in "alloca".
102#else
103#error Unknown or unsupported OS.
104#endif
105
106/* KMP_SRC_LOC_DECL -- Declaring source location paramemters, to be used in
107   function declaration.
108   KMP_SRC_LOC_PARM -- Source location paramemters, to be used to pass
109   parameters to underlying levels.
110   KMP_SRC_LOC_CURR -- Source location arguments describing current location,
111   to be used at top-level.
112
113   Typical usage:
114   void * _aligned_malloc( int size KMP_SRC_LOC_DECL ) {
115     // Note: Comma is missed before KMP_SRC_LOC_DECL.
116     KE_TRACE( 25, ( "called from %s:%d\n", KMP_SRC_LOC_PARM ) );
117     ...
118   }
119   #define aligned_malloc( size ) _aligned_malloc( (size) KMP_SRC_LOC_CURR )
120   // Use macro instead of direct call to function -- macro passes info
121   // about current source location to the func.
122*/
123#if KMP_DEBUG
124#define KMP_SRC_LOC_DECL , char const *_file_, int _line_
125#define KMP_SRC_LOC_PARM , _file_, _line_
126#define KMP_SRC_LOC_CURR , __FILE__, __LINE__
127#else
128#define KMP_SRC_LOC_DECL
129#define KMP_SRC_LOC_PARM
130#define KMP_SRC_LOC_CURR
131#endif // KMP_DEBUG
132
133/* malloc_src_loc() and free_src_loc() are pseudo-functions (really macros)
134   with accepts extra arguments (source location info) in debug mode. They
135   should be used in place of malloc() and free(), this allows enabling native
136   memory debugging capabilities (if any).
137
138   Typical usage:
139   ptr = malloc_src_loc( size KMP_SRC_LOC_PARM );
140   // Inside memory allocation wrapper, or
141   ptr = malloc_src_loc( size KMP_SRC_LOC_CURR );
142   // Outside of memory allocation wrapper.
143*/
144#define malloc_src_loc(args) _malloc_src_loc(args)
145#define free_src_loc(args) _free_src_loc(args)
146/* Depending on build mode (debug or release), malloc_src_loc is declared with
147   1 or 3 parameters, but calls to malloc_src_loc() are always the same:
148
149   ... malloc_src_loc( size KMP_SRC_LOC_PARM ); // or KMP_SRC_LOC_CURR
150
151   Compiler issues warning/error "too few arguments in macro invocation".
152   Declaring two macros, malloc_src_loc() and _malloc_src_loc(), overcomes the
153   problem. */
154
155#if KMP_DEBUG
156
157#if KMP_OS_WINDOWS && _DEBUG
158// KMP_DEBUG != _DEBUG. MS debug RTL is available only if _DEBUG is defined.
159
160// Windows* OS has native memory debugging capabilities. Enable them.
161
162#include <crtdbg.h>
163
164#define KMP_MEM_BLOCK _CLIENT_BLOCK
165#define malloc(size) _malloc_dbg((size), KMP_MEM_BLOCK, __FILE__, __LINE__)
166#define calloc(num, size)                                                      \
167  _calloc_dbg((num), (size), KMP_MEM_BLOCK, __FILE__, __LINE__)
168#define realloc(ptr, size)                                                     \
169  _realloc_dbg((ptr), (size), KMP_MEM_BLOCK, __FILE__, __LINE__)
170#define free(ptr) _free_dbg((ptr), KMP_MEM_BLOCK)
171
172#define _malloc_src_loc(size, file, line)                                      \
173  _malloc_dbg((size), KMP_MEM_BLOCK, (file), (line))
174#define _free_src_loc(ptr, file, line) _free_dbg((ptr), KMP_MEM_BLOCK)
175
176#else
177
178// Linux* OS, OS X*, or non-debug Windows* OS.
179
180#define _malloc_src_loc(size, file, line) malloc((size))
181#define _free_src_loc(ptr, file, line) free((ptr))
182
183#endif
184
185#else
186
187// In release build malloc_src_loc() and free_src_loc() do not have extra
188// parameters.
189#define _malloc_src_loc(size) malloc((size))
190#define _free_src_loc(ptr) free((ptr))
191
192#endif // KMP_DEBUG
193
194#endif // KMP_WRAPPER_MALLOC_H
195
196// end of file //
197