1 /* ===-- assembly.h - libUnwind assembler support macros -------------------===
2  *
3  * Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4  * See https://llvm.org/LICENSE.txt for license information.
5  * SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6  *
7  * ===----------------------------------------------------------------------===
8  *
9  * This file defines macros for use in libUnwind assembler source.
10  * This file is not part of the interface of this library.
11  *
12  * ===----------------------------------------------------------------------===
13  */
14 
15 #ifndef UNWIND_ASSEMBLY_H
16 #define UNWIND_ASSEMBLY_H
17 
18 #if defined(__powerpc64__)
19 #define SEPARATOR ;
20 #define PPC64_OFFS_SRR0   0
21 #define PPC64_OFFS_CR     272
22 #define PPC64_OFFS_XER    280
23 #define PPC64_OFFS_LR     288
24 #define PPC64_OFFS_CTR    296
25 #define PPC64_OFFS_VRSAVE 304
26 #define PPC64_OFFS_FP     312
27 #define PPC64_OFFS_V      824
28 #elif defined(__APPLE__) && defined(__aarch64__)
29 #define SEPARATOR %%
30 #else
31 #define SEPARATOR ;
32 #endif
33 
34 #if defined(__powerpc64__) && (!defined(_CALL_ELF) || _CALL_ELF == 1)
35 #define PPC64_OPD1 .section .opd,"aw",@progbits SEPARATOR
36 #define PPC64_OPD2 SEPARATOR \
37   .p2align 3 SEPARATOR \
38   .quad .Lfunc_begin0 SEPARATOR \
39   .quad .TOC.@tocbase SEPARATOR \
40   .quad 0 SEPARATOR \
41   .text SEPARATOR \
42 .Lfunc_begin0:
43 #else
44 #define PPC64_OPD1
45 #define PPC64_OPD2
46 #endif
47 
48 #if defined(__ARM_FEATURE_BTI_DEFAULT)
49   .pushsection ".note.gnu.property", "a" SEPARATOR                             \
50   .balign 8 SEPARATOR                                                          \
51   .long 4 SEPARATOR                                                            \
52   .long 0x10 SEPARATOR                                                         \
53   .long 0x5 SEPARATOR                                                          \
54   .asciz "GNU" SEPARATOR                                                       \
55   .long 0xc0000000 SEPARATOR /* GNU_PROPERTY_AARCH64_FEATURE_1_AND */          \
56   .long 4 SEPARATOR                                                            \
57   .long 3 SEPARATOR /* GNU_PROPERTY_AARCH64_FEATURE_1_BTI AND */               \
58                     /* GNU_PROPERTY_AARCH64_FEATURE_1_PAC */                   \
59   .long 0 SEPARATOR                                                            \
60   .popsection SEPARATOR
61 #define AARCH64_BTI  bti c
62 #else
63 #define AARCH64_BTI
64 #endif
65 
66 #define GLUE2(a, b) a ## b
67 #define GLUE(a, b) GLUE2(a, b)
68 #define SYMBOL_NAME(name) GLUE(__USER_LABEL_PREFIX__, name)
69 
70 #if defined(__APPLE__)
71 
72 #define SYMBOL_IS_FUNC(name)
73 #define EXPORT_SYMBOL(name)
74 #define HIDDEN_SYMBOL(name) .private_extern name
75 #define WEAK_SYMBOL(name) .weak_reference name
76 #define WEAK_ALIAS(name, aliasname)                                            \
77   .globl SYMBOL_NAME(aliasname) SEPARATOR                                      \
78   WEAK_SYMBOL(aliasname) SEPARATOR                                             \
79   SYMBOL_NAME(aliasname) = SYMBOL_NAME(name)
80 
81 #define NO_EXEC_STACK_DIRECTIVE
82 
83 #elif defined(__ELF__)
84 
85 #if defined(__arm__)
86 #define SYMBOL_IS_FUNC(name) .type name,%function
87 #else
88 #define SYMBOL_IS_FUNC(name) .type name,@function
89 #endif
90 #define EXPORT_SYMBOL(name)
91 #define HIDDEN_SYMBOL(name) .hidden name
92 #define WEAK_SYMBOL(name) .weak name
93 
94 #if defined(__hexagon__)
95 #define WEAK_ALIAS(name, aliasname) \
96   WEAK_SYMBOL(aliasname) SEPARATOR                                             \
97   .equiv SYMBOL_NAME(aliasname), SYMBOL_NAME(name)
98 #else
99 #define WEAK_ALIAS(name, aliasname)                                            \
100   WEAK_SYMBOL(aliasname) SEPARATOR                                             \
101   SYMBOL_NAME(aliasname) = SYMBOL_NAME(name)
102 #endif
103 
104 #if defined(__GNU__) || defined(__FreeBSD__) || defined(__Fuchsia__) || \
105     defined(__linux__)
106 #define NO_EXEC_STACK_DIRECTIVE .section .note.GNU-stack,"",%progbits
107 #else
108 #define NO_EXEC_STACK_DIRECTIVE
109 #endif
110 
111 #elif defined(_WIN32)
112 
113 #define SYMBOL_IS_FUNC(name)                                                   \
114   .def name SEPARATOR                                                          \
115     .scl 2 SEPARATOR                                                           \
116     .type 32 SEPARATOR                                                         \
117   .endef
118 #define EXPORT_SYMBOL2(name)                                                   \
119   .section .drectve,"yn" SEPARATOR                                             \
120   .ascii "-export:", #name, "\0" SEPARATOR                                     \
121   .text
122 #if defined(_LIBUNWIND_DISABLE_VISIBILITY_ANNOTATIONS)
123 #define EXPORT_SYMBOL(name)
124 #else
125 #define EXPORT_SYMBOL(name) EXPORT_SYMBOL2(name)
126 #endif
127 #define HIDDEN_SYMBOL(name)
128 
129 #if defined(__MINGW32__)
130 #define WEAK_ALIAS(name, aliasname)                                            \
131   .globl SYMBOL_NAME(aliasname) SEPARATOR                                      \
132   EXPORT_SYMBOL(aliasname) SEPARATOR                                           \
133   SYMBOL_NAME(aliasname) = SYMBOL_NAME(name)
134 #else
135 #define WEAK_ALIAS3(name, aliasname)                                           \
136   .section .drectve,"yn" SEPARATOR                                             \
137   .ascii "-alternatename:", #aliasname, "=", #name, "\0" SEPARATOR             \
138   .text
139 #define WEAK_ALIAS2(name, aliasname)                                           \
140   WEAK_ALIAS3(name, aliasname)
141 #define WEAK_ALIAS(name, aliasname)                                            \
142   EXPORT_SYMBOL(SYMBOL_NAME(aliasname)) SEPARATOR                              \
143   WEAK_ALIAS2(SYMBOL_NAME(name), SYMBOL_NAME(aliasname))
144 #endif
145 
146 #define NO_EXEC_STACK_DIRECTIVE
147 
148 #elif defined(__sparc__)
149 
150 #else
151 
152 #error Unsupported target
153 
154 #endif
155 
156 #define DEFINE_LIBUNWIND_FUNCTION(name)                                        \
157   .globl SYMBOL_NAME(name) SEPARATOR                                           \
158   HIDDEN_SYMBOL(SYMBOL_NAME(name)) SEPARATOR                                   \
159   SYMBOL_IS_FUNC(SYMBOL_NAME(name)) SEPARATOR                                  \
160   PPC64_OPD1                                                                   \
161   SYMBOL_NAME(name):                                                           \
162   PPC64_OPD2                                                                   \
163   AARCH64_BTI
164 
165 #if defined(__arm__)
166 #if !defined(__ARM_ARCH)
167 #define __ARM_ARCH 4
168 #endif
169 
170 #if defined(__ARM_ARCH_4T__) || __ARM_ARCH >= 5
171 #define ARM_HAS_BX
172 #endif
173 
174 #ifdef ARM_HAS_BX
175 #define JMP(r) bx r
176 #else
177 #define JMP(r) mov pc, r
178 #endif
179 #endif /* __arm__ */
180 
181 #endif /* UNWIND_ASSEMBLY_H */
182