1 /*
2  * Copyright (C) 2008 The Android Open Source Project
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  *  * Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  *  * Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in
12  *    the documentation and/or other materials provided with the
13  *    distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
16  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
17  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
18  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
19  * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
22  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
25  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #if defined(__clang__)
30 // clang interprets -fno-builtin more loosely than you might expect,
31 // and thinks it's okay to still substitute builtins as long as they're
32 // named __aeabi_* rather than __builtin_*, which causes infinite
33 // recursion if we have the fortified memcpy visible in this file.
34 #undef _FORTIFY_SOURCE
35 #endif
36 
37 #include <stddef.h>
38 #include <string.h>
39 
40 extern int __cxa_atexit(void (*)(void*), void*, void*);
41 
42 // All of these are weak symbols to avoid multiple definition errors when
43 // linking with libstdc++-v3 or compiler-rt.
44 
45 /* The "C++ ABI for ARM" document states that static C++ constructors,
46  * which are called from the .init_array, should manually call
47  * __aeabi_atexit() to register static destructors explicitly.
48  *
49  * Note that 'dso_handle' is the address of a magic linker-generate
50  * variable from the shared object that contains the constructor/destructor
51  */
52 
53 int __attribute__((weak))
__aeabi_atexit_impl(void * object,void (* destructor)(void *),void * dso_handle)54 __aeabi_atexit_impl(void *object, void (*destructor) (void *), void *dso_handle) {
55     return __cxa_atexit(destructor, object, dso_handle);
56 }
57 
58 int __attribute__((weak))
__aeabi_atexit_impl2(void * object,void (* destructor)(void *),void * dso_handle)59 __aeabi_atexit_impl2(void *object, void (*destructor) (void *), void *dso_handle) {
60     return __cxa_atexit(destructor, object, dso_handle);
61 }
62 
63 
__aeabi_memcpy8_impl(void * dest,const void * src,size_t n)64 void __attribute__((weak)) __aeabi_memcpy8_impl(void *dest, const void *src, size_t n) {
65     memcpy(dest, src, n);
66 }
67 
__aeabi_memcpy4_impl(void * dest,const void * src,size_t n)68 void __attribute__((weak)) __aeabi_memcpy4_impl(void *dest, const void *src, size_t n) {
69     memcpy(dest, src, n);
70 }
71 
__aeabi_memcpy_impl(void * dest,const void * src,size_t n)72 void __attribute__((weak)) __aeabi_memcpy_impl(void *dest, const void *src, size_t n) {
73     memcpy(dest, src, n);
74 }
75 
__aeabi_memcpy8_impl2(void * dest,const void * src,size_t n)76 void __attribute__((weak)) __aeabi_memcpy8_impl2(void *dest, const void *src, size_t n) {
77     memcpy(dest, src, n);
78 }
79 
__aeabi_memcpy4_impl2(void * dest,const void * src,size_t n)80 void __attribute__((weak)) __aeabi_memcpy4_impl2(void *dest, const void *src, size_t n) {
81     memcpy(dest, src, n);
82 }
83 
__aeabi_memcpy_impl2(void * dest,const void * src,size_t n)84 void __attribute__((weak)) __aeabi_memcpy_impl2(void *dest, const void *src, size_t n) {
85     memcpy(dest, src, n);
86 }
87 
88 
__aeabi_memmove8_impl(void * dest,const void * src,size_t n)89 void __attribute__((weak)) __aeabi_memmove8_impl(void *dest, const void *src, size_t n) {
90     memmove(dest, src, n);
91 }
92 
__aeabi_memmove4_impl(void * dest,const void * src,size_t n)93 void __attribute__((weak)) __aeabi_memmove4_impl(void *dest, const void *src, size_t n) {
94     memmove(dest, src, n);
95 }
96 
__aeabi_memmove_impl(void * dest,const void * src,size_t n)97 void __attribute__((weak)) __aeabi_memmove_impl(void *dest, const void *src, size_t n) {
98     memmove(dest, src, n);
99 }
100 
__aeabi_memmove8_impl2(void * dest,const void * src,size_t n)101 void __attribute__((weak)) __aeabi_memmove8_impl2(void *dest, const void *src, size_t n) {
102     memmove(dest, src, n);
103 }
104 
__aeabi_memmove4_impl2(void * dest,const void * src,size_t n)105 void __attribute__((weak)) __aeabi_memmove4_impl2(void *dest, const void *src, size_t n) {
106     memmove(dest, src, n);
107 }
108 
__aeabi_memmove_impl2(void * dest,const void * src,size_t n)109 void __attribute__((weak)) __aeabi_memmove_impl2(void *dest, const void *src, size_t n) {
110     memmove(dest, src, n);
111 }
112 
113 /*
114  * __aeabi_memset has the order of its second and third arguments reversed.
115  *  This allows __aeabi_memclr to tail-call __aeabi_memset
116  */
117 
__aeabi_memset8_impl(void * dest,size_t n,int c)118 void __attribute__((weak)) __aeabi_memset8_impl(void *dest, size_t n, int c) {
119     memset(dest, c, n);
120 }
121 
__aeabi_memset4_impl(void * dest,size_t n,int c)122 void __attribute__((weak)) __aeabi_memset4_impl(void *dest, size_t n, int c) {
123     memset(dest, c, n);
124 }
125 
__aeabi_memset_impl(void * dest,size_t n,int c)126 void __attribute__((weak)) __aeabi_memset_impl(void *dest, size_t n, int c) {
127     memset(dest, c, n);
128 }
129 
__aeabi_memset8_impl2(void * dest,size_t n,int c)130 void __attribute__((weak)) __aeabi_memset8_impl2(void *dest, size_t n, int c) {
131     memset(dest, c, n);
132 }
133 
__aeabi_memset4_impl2(void * dest,size_t n,int c)134 void __attribute__((weak)) __aeabi_memset4_impl2(void *dest, size_t n, int c) {
135     memset(dest, c, n);
136 }
137 
__aeabi_memset_impl2(void * dest,size_t n,int c)138 void __attribute__((weak)) __aeabi_memset_impl2(void *dest, size_t n, int c) {
139     memset(dest, c, n);
140 }
141 
142 
__aeabi_memclr8_impl(void * dest,size_t n)143 void __attribute__((weak)) __aeabi_memclr8_impl(void *dest, size_t n) {
144     __aeabi_memset8_impl(dest, n, 0);
145 }
146 
__aeabi_memclr4_impl(void * dest,size_t n)147 void __attribute__((weak)) __aeabi_memclr4_impl(void *dest, size_t n) {
148     __aeabi_memset4_impl(dest, n, 0);
149 }
150 
__aeabi_memclr_impl(void * dest,size_t n)151 void __attribute__((weak)) __aeabi_memclr_impl(void *dest, size_t n) {
152     __aeabi_memset_impl(dest, n, 0);
153 }
154 
__aeabi_memclr8_impl2(void * dest,size_t n)155 void __attribute__((weak)) __aeabi_memclr8_impl2(void *dest, size_t n) {
156     __aeabi_memset8_impl(dest, n, 0);
157 }
158 
__aeabi_memclr4_impl2(void * dest,size_t n)159 void __attribute__((weak)) __aeabi_memclr4_impl2(void *dest, size_t n) {
160     __aeabi_memset4_impl(dest, n, 0);
161 }
162 
__aeabi_memclr_impl2(void * dest,size_t n)163 void __attribute__((weak)) __aeabi_memclr_impl2(void *dest, size_t n) {
164     __aeabi_memset_impl(dest, n, 0);
165 }
166 
167 #define __AEABI_SYMVERS(fn_name) \
168 __asm__(".symver " #fn_name "_impl, " #fn_name "@@LIBC_N"); \
169 __asm__(".symver " #fn_name "_impl2, " #fn_name "@LIBC_PRIVATE")
170 
171 __AEABI_SYMVERS(__aeabi_atexit);
172 __AEABI_SYMVERS(__aeabi_memcpy8);
173 __AEABI_SYMVERS(__aeabi_memcpy4);
174 __AEABI_SYMVERS(__aeabi_memcpy);
175 __AEABI_SYMVERS(__aeabi_memmove8);
176 __AEABI_SYMVERS(__aeabi_memmove4);
177 __AEABI_SYMVERS(__aeabi_memmove);
178 __AEABI_SYMVERS(__aeabi_memset8);
179 __AEABI_SYMVERS(__aeabi_memset4);
180 __AEABI_SYMVERS(__aeabi_memset);
181 __AEABI_SYMVERS(__aeabi_memclr8);
182 __AEABI_SYMVERS(__aeabi_memclr4);
183 __AEABI_SYMVERS(__aeabi_memclr);
184 
185 #undef __AEABI_SYMVERS
186