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111
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1 /* DWARF2 exception handling and frame unwind runtime interface routines.
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2 Copyright (C) 1997-2017 Free Software Foundation, Inc.
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3
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4 This file is part of GCC.
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5
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6 GCC is free software; you can redistribute it and/or modify it
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7 under the terms of the GNU General Public License as published by
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8 the Free Software Foundation; either version 3, or (at your option)
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9 any later version.
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10
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11 GCC is distributed in the hope that it will be useful, but WITHOUT
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12 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
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13 or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
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14 License for more details.
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15
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16 Under Section 7 of GPL version 3, you are granted additional
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17 permissions described in the GCC Runtime Library Exception, version
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18 3.1, as published by the Free Software Foundation.
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19
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20 You should have received a copy of the GNU General Public License and
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21 a copy of the GCC Runtime Library Exception along with this program;
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22 see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
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23 <http://www.gnu.org/licenses/>. */
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24
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25 #include "tconfig.h"
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26 #include "tsystem.h"
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27 #include "coretypes.h"
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28 #include "tm.h"
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29 #include "libgcc_tm.h"
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30 #include "dwarf2.h"
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31 #include "unwind.h"
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32 #ifdef __USING_SJLJ_EXCEPTIONS__
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33 # define NO_SIZE_OF_ENCODED_VALUE
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34 #endif
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35 #include "unwind-pe.h"
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36 #include "unwind-dw2-fde.h"
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37 #include "gthr.h"
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38 #include "unwind-dw2.h"
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39
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40 #ifdef HAVE_SYS_SDT_H
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41 #include <sys/sdt.h>
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42 #endif
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43
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44 #ifndef __USING_SJLJ_EXCEPTIONS__
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45
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46 #ifndef __LIBGCC_STACK_GROWS_DOWNWARD__
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47 #define __LIBGCC_STACK_GROWS_DOWNWARD__ 0
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48 #else
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49 #undef __LIBGCC_STACK_GROWS_DOWNWARD__
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50 #define __LIBGCC_STACK_GROWS_DOWNWARD__ 1
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51 #endif
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52
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53 /* Dwarf frame registers used for pre gcc 3.0 compiled glibc. */
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54 #ifndef PRE_GCC3_DWARF_FRAME_REGISTERS
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55 #define PRE_GCC3_DWARF_FRAME_REGISTERS __LIBGCC_DWARF_FRAME_REGISTERS__
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56 #endif
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57
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58 /* ??? For the public function interfaces, we tend to gcc_assert that the
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59 column numbers are in range. For the dwarf2 unwind info this does happen,
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60 although so far in a case that doesn't actually matter.
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61
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62 See PR49146, in which a call from x86_64 ms abi to x86_64 unix abi stores
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63 the call-saved xmm registers and annotates them. We havn't bothered
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64 providing support for the xmm registers for the x86_64 port primarily
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65 because the 64-bit windows targets don't use dwarf2 unwind, using sjlj or
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66 SEH instead. Adding the support for unix targets would generally be a
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67 waste. However, some runtime libraries supplied with ICC do contain such
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68 an unorthodox transition, as well as the unwind info to match. This loss
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69 of register restoration doesn't matter in practice, because the exception
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70 is caught in the native unix abi, where all of the xmm registers are
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71 call clobbered.
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72
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73 Ideally, we'd record some bit to notice when we're failing to restore some
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74 register recorded in the unwind info, but to do that we need annotation on
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75 the unix->ms abi edge, so that we know when the register data may be
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76 discarded. And since this edge is also within the ICC library, we're
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77 unlikely to be able to get the new annotation.
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78
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79 Barring a magic solution to restore the ms abi defined 128-bit xmm registers
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80 (as distictly opposed to the full runtime width) without causing extra
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81 overhead for normal unix abis, the best solution seems to be to simply
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82 ignore unwind data for unknown columns. */
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83
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84 #define UNWIND_COLUMN_IN_RANGE(x) \
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85 __builtin_expect((x) <= __LIBGCC_DWARF_FRAME_REGISTERS__, 1)
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86
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87 #ifdef REG_VALUE_IN_UNWIND_CONTEXT
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88 typedef _Unwind_Word _Unwind_Context_Reg_Val;
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89
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90 #ifndef ASSUME_EXTENDED_UNWIND_CONTEXT
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91 #define ASSUME_EXTENDED_UNWIND_CONTEXT 1
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92 #endif
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93
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94 static inline _Unwind_Word
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95 _Unwind_Get_Unwind_Word (_Unwind_Context_Reg_Val val)
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96 {
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97 return val;
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98 }
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99
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100 static inline _Unwind_Context_Reg_Val
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101 _Unwind_Get_Unwind_Context_Reg_Val (_Unwind_Word val)
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102 {
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103 return val;
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104 }
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105 #else
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106 typedef void *_Unwind_Context_Reg_Val;
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107
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108 static inline _Unwind_Word
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109 _Unwind_Get_Unwind_Word (_Unwind_Context_Reg_Val val)
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110 {
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111 return (_Unwind_Word) (_Unwind_Internal_Ptr) val;
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112 }
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113
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114 static inline _Unwind_Context_Reg_Val
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115 _Unwind_Get_Unwind_Context_Reg_Val (_Unwind_Word val)
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116 {
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117 return (_Unwind_Context_Reg_Val) (_Unwind_Internal_Ptr) val;
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118 }
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119 #endif
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120
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121 #ifndef ASSUME_EXTENDED_UNWIND_CONTEXT
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122 #define ASSUME_EXTENDED_UNWIND_CONTEXT 0
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123 #endif
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124
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125 /* This is the register and unwind state for a particular frame. This
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126 provides the information necessary to unwind up past a frame and return
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127 to its caller. */
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128 struct _Unwind_Context
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129 {
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130 _Unwind_Context_Reg_Val reg[__LIBGCC_DWARF_FRAME_REGISTERS__+1];
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131 void *cfa;
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132 void *ra;
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133 void *lsda;
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134 struct dwarf_eh_bases bases;
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135 /* Signal frame context. */
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136 #define SIGNAL_FRAME_BIT ((~(_Unwind_Word) 0 >> 1) + 1)
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137 /* Context which has version/args_size/by_value fields. */
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138 #define EXTENDED_CONTEXT_BIT ((~(_Unwind_Word) 0 >> 2) + 1)
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139 /* Bit reserved on AArch64, return address has been signed with A key. */
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140 #define RA_A_SIGNED_BIT ((~(_Unwind_Word) 0 >> 3) + 1)
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141 _Unwind_Word flags;
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142 /* 0 for now, can be increased when further fields are added to
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143 struct _Unwind_Context. */
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144 _Unwind_Word version;
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145 _Unwind_Word args_size;
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146 char by_value[__LIBGCC_DWARF_FRAME_REGISTERS__+1];
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147 };
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148
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149 /* Byte size of every register managed by these routines. */
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150 static unsigned char dwarf_reg_size_table[__LIBGCC_DWARF_FRAME_REGISTERS__+1];
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151
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152
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153 /* Read unaligned data from the instruction buffer. */
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154
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155 union unaligned
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156 {
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157 void *p;
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158 unsigned u2 __attribute__ ((mode (HI)));
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159 unsigned u4 __attribute__ ((mode (SI)));
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160 unsigned u8 __attribute__ ((mode (DI)));
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161 signed s2 __attribute__ ((mode (HI)));
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162 signed s4 __attribute__ ((mode (SI)));
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163 signed s8 __attribute__ ((mode (DI)));
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164 } __attribute__ ((packed));
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165
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166 static void uw_update_context (struct _Unwind_Context *, _Unwind_FrameState *);
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167 static _Unwind_Reason_Code uw_frame_state_for (struct _Unwind_Context *,
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168 _Unwind_FrameState *);
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169
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170 static inline void *
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171 read_pointer (const void *p) { const union unaligned *up = p; return up->p; }
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172
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173 static inline int
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174 read_1u (const void *p) { return *(const unsigned char *) p; }
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175
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176 static inline int
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177 read_1s (const void *p) { return *(const signed char *) p; }
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178
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179 static inline int
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180 read_2u (const void *p) { const union unaligned *up = p; return up->u2; }
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181
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182 static inline int
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183 read_2s (const void *p) { const union unaligned *up = p; return up->s2; }
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184
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185 static inline unsigned int
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186 read_4u (const void *p) { const union unaligned *up = p; return up->u4; }
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187
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188 static inline int
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189 read_4s (const void *p) { const union unaligned *up = p; return up->s4; }
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190
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191 static inline unsigned long
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192 read_8u (const void *p) { const union unaligned *up = p; return up->u8; }
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193
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194 static inline unsigned long
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195 read_8s (const void *p) { const union unaligned *up = p; return up->s8; }
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196
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197 static inline _Unwind_Word
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198 _Unwind_IsSignalFrame (struct _Unwind_Context *context)
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199 {
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200 return (context->flags & SIGNAL_FRAME_BIT) ? 1 : 0;
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201 }
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202
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203 static inline void
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204 _Unwind_SetSignalFrame (struct _Unwind_Context *context, int val)
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205 {
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206 if (val)
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207 context->flags |= SIGNAL_FRAME_BIT;
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208 else
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209 context->flags &= ~SIGNAL_FRAME_BIT;
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210 }
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211
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212 static inline _Unwind_Word
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213 _Unwind_IsExtendedContext (struct _Unwind_Context *context)
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214 {
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215 return (ASSUME_EXTENDED_UNWIND_CONTEXT
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216 || (context->flags & EXTENDED_CONTEXT_BIT));
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217 }
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218
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219 /* Get the value of register INDEX as saved in CONTEXT. */
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220
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221 inline _Unwind_Word
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222 _Unwind_GetGR (struct _Unwind_Context *context, int index)
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223 {
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224 int size;
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225 _Unwind_Context_Reg_Val val;
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226
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227 #ifdef DWARF_ZERO_REG
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228 if (index == DWARF_ZERO_REG)
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229 return 0;
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230 #endif
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231
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232 index = DWARF_REG_TO_UNWIND_COLUMN (index);
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233 gcc_assert (index < (int) sizeof(dwarf_reg_size_table));
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234 size = dwarf_reg_size_table[index];
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235 val = context->reg[index];
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236
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237 if (_Unwind_IsExtendedContext (context) && context->by_value[index])
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238 return _Unwind_Get_Unwind_Word (val);
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239
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240 /* This will segfault if the register hasn't been saved. */
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241 if (size == sizeof(_Unwind_Ptr))
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242 return * (_Unwind_Ptr *) (_Unwind_Internal_Ptr) val;
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243 else
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244 {
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245 gcc_assert (size == sizeof(_Unwind_Word));
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246 return * (_Unwind_Word *) (_Unwind_Internal_Ptr) val;
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247 }
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248 }
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249
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250 static inline void *
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251 _Unwind_GetPtr (struct _Unwind_Context *context, int index)
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252 {
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253 return (void *)(_Unwind_Ptr) _Unwind_GetGR (context, index);
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254 }
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255
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256 /* Get the value of the CFA as saved in CONTEXT. */
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257
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258 _Unwind_Word
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259 _Unwind_GetCFA (struct _Unwind_Context *context)
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260 {
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261 return (_Unwind_Ptr) context->cfa;
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262 }
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263
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264 /* Overwrite the saved value for register INDEX in CONTEXT with VAL. */
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265
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266 inline void
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267 _Unwind_SetGR (struct _Unwind_Context *context, int index, _Unwind_Word val)
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268 {
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269 int size;
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270 void *ptr;
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271
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272 index = DWARF_REG_TO_UNWIND_COLUMN (index);
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273 gcc_assert (index < (int) sizeof(dwarf_reg_size_table));
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274 size = dwarf_reg_size_table[index];
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275
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276 if (_Unwind_IsExtendedContext (context) && context->by_value[index])
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277 {
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278 context->reg[index] = _Unwind_Get_Unwind_Context_Reg_Val (val);
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279 return;
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280 }
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281
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282 ptr = (void *) (_Unwind_Internal_Ptr) context->reg[index];
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283
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284 if (size == sizeof(_Unwind_Ptr))
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285 * (_Unwind_Ptr *) ptr = val;
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286 else
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287 {
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288 gcc_assert (size == sizeof(_Unwind_Word));
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289 * (_Unwind_Word *) ptr = val;
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290 }
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291 }
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292
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293 /* Get the pointer to a register INDEX as saved in CONTEXT. */
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294
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295 static inline void *
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296 _Unwind_GetGRPtr (struct _Unwind_Context *context, int index)
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297 {
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298 index = DWARF_REG_TO_UNWIND_COLUMN (index);
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299 if (_Unwind_IsExtendedContext (context) && context->by_value[index])
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300 return &context->reg[index];
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301 return (void *) (_Unwind_Internal_Ptr) context->reg[index];
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302 }
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303
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304 /* Set the pointer to a register INDEX as saved in CONTEXT. */
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305
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306 static inline void
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307 _Unwind_SetGRPtr (struct _Unwind_Context *context, int index, void *p)
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308 {
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309 index = DWARF_REG_TO_UNWIND_COLUMN (index);
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310 if (_Unwind_IsExtendedContext (context))
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311 context->by_value[index] = 0;
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312 context->reg[index] = (_Unwind_Context_Reg_Val) (_Unwind_Internal_Ptr) p;
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313 }
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314
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315 /* Overwrite the saved value for register INDEX in CONTEXT with VAL. */
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316
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317 static inline void
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318 _Unwind_SetGRValue (struct _Unwind_Context *context, int index,
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319 _Unwind_Word val)
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320 {
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321 index = DWARF_REG_TO_UNWIND_COLUMN (index);
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322 gcc_assert (index < (int) sizeof(dwarf_reg_size_table));
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323 /* Return column size may be smaller than _Unwind_Context_Reg_Val. */
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324 gcc_assert (dwarf_reg_size_table[index] <= sizeof (_Unwind_Context_Reg_Val));
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325
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326 context->by_value[index] = 1;
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327 context->reg[index] = _Unwind_Get_Unwind_Context_Reg_Val (val);
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328 }
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329
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330 /* Return nonzero if register INDEX is stored by value rather than
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331 by reference. */
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332
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333 static inline int
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334 _Unwind_GRByValue (struct _Unwind_Context *context, int index)
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335 {
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336 index = DWARF_REG_TO_UNWIND_COLUMN (index);
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337 return context->by_value[index];
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338 }
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339
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340 /* Retrieve the return address for CONTEXT. */
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341
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342 inline _Unwind_Ptr
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343 _Unwind_GetIP (struct _Unwind_Context *context)
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344 {
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345 return (_Unwind_Ptr) context->ra;
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346 }
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347
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348 /* Retrieve the return address and flag whether that IP is before
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349 or after first not yet fully executed instruction. */
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350
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351 inline _Unwind_Ptr
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352 _Unwind_GetIPInfo (struct _Unwind_Context *context, int *ip_before_insn)
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353 {
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354 *ip_before_insn = _Unwind_IsSignalFrame (context);
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355 return (_Unwind_Ptr) context->ra;
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356 }
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357
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358 /* Overwrite the return address for CONTEXT with VAL. */
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359
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360 inline void
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361 _Unwind_SetIP (struct _Unwind_Context *context, _Unwind_Ptr val)
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362 {
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363 context->ra = (void *) val;
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364 }
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365
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366 void *
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367 _Unwind_GetLanguageSpecificData (struct _Unwind_Context *context)
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368 {
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369 return context->lsda;
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370 }
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371
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372 _Unwind_Ptr
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373 _Unwind_GetRegionStart (struct _Unwind_Context *context)
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374 {
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375 return (_Unwind_Ptr) context->bases.func;
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376 }
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377
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378 void *
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379 _Unwind_FindEnclosingFunction (void *pc)
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380 {
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381 struct dwarf_eh_bases bases;
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382 const struct dwarf_fde *fde = _Unwind_Find_FDE (pc-1, &bases);
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383 if (fde)
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384 return bases.func;
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385 else
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386 return NULL;
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387 }
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388
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389 #ifndef __ia64__
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390 _Unwind_Ptr
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391 _Unwind_GetDataRelBase (struct _Unwind_Context *context)
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392 {
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393 return (_Unwind_Ptr) context->bases.dbase;
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394 }
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395
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|
396 _Unwind_Ptr
|
|
|
397 _Unwind_GetTextRelBase (struct _Unwind_Context *context)
|
|
|
398 {
|
|
|
399 return (_Unwind_Ptr) context->bases.tbase;
|
|
|
400 }
|
|
|
401 #endif
|
|
|
402
|
|
|
403 #include "md-unwind-support.h"
|
|
|
404
|
|
|
405 /* Extract any interesting information from the CIE for the translation
|
|
|
406 unit F belongs to. Return a pointer to the byte after the augmentation,
|
|
|
407 or NULL if we encountered an undecipherable augmentation. */
|
|
|
408
|
|
|
409 static const unsigned char *
|
|
|
410 extract_cie_info (const struct dwarf_cie *cie, struct _Unwind_Context *context,
|
|
|
411 _Unwind_FrameState *fs)
|
|
|
412 {
|
|
|
413 const unsigned char *aug = cie->augmentation;
|
|
|
414 const unsigned char *p = aug + strlen ((const char *)aug) + 1;
|
|
|
415 const unsigned char *ret = NULL;
|
|
|
416 _uleb128_t utmp;
|
|
|
417 _sleb128_t stmp;
|
|
|
418
|
|
|
419 /* g++ v2 "eh" has pointer immediately following augmentation string,
|
|
|
420 so it must be handled first. */
|
|
|
421 if (aug[0] == 'e' && aug[1] == 'h')
|
|
|
422 {
|
|
|
423 fs->eh_ptr = read_pointer (p);
|
|
|
424 p += sizeof (void *);
|
|
|
425 aug += 2;
|
|
|
426 }
|
|
|
427
|
|
|
428 /* After the augmentation resp. pointer for "eh" augmentation
|
|
|
429 follows for CIE version >= 4 address size byte and
|
|
|
430 segment size byte. */
|
|
|
431 if (__builtin_expect (cie->version >= 4, 0))
|
|
|
432 {
|
|
|
433 if (p[0] != sizeof (void *) || p[1] != 0)
|
|
|
434 return NULL;
|
|
|
435 p += 2;
|
|
|
436 }
|
|
|
437 /* Immediately following this are the code and
|
|
|
438 data alignment and return address column. */
|
|
|
439 p = read_uleb128 (p, &utmp);
|
|
|
440 fs->code_align = (_Unwind_Word)utmp;
|
|
|
441 p = read_sleb128 (p, &stmp);
|
|
|
442 fs->data_align = (_Unwind_Sword)stmp;
|
|
|
443 if (cie->version == 1)
|
|
|
444 fs->retaddr_column = *p++;
|
|
|
445 else
|
|
|
446 {
|
|
|
447 p = read_uleb128 (p, &utmp);
|
|
|
448 fs->retaddr_column = (_Unwind_Word)utmp;
|
|
|
449 }
|
|
|
450 fs->lsda_encoding = DW_EH_PE_omit;
|
|
|
451
|
|
|
452 /* If the augmentation starts with 'z', then a uleb128 immediately
|
|
|
453 follows containing the length of the augmentation field following
|
|
|
454 the size. */
|
|
|
455 if (*aug == 'z')
|
|
|
456 {
|
|
|
457 p = read_uleb128 (p, &utmp);
|
|
|
458 ret = p + utmp;
|
|
|
459
|
|
|
460 fs->saw_z = 1;
|
|
|
461 ++aug;
|
|
|
462 }
|
|
|
463
|
|
|
464 /* Iterate over recognized augmentation subsequences. */
|
|
|
465 while (*aug != '\0')
|
|
|
466 {
|
|
|
467 /* "L" indicates a byte showing how the LSDA pointer is encoded. */
|
|
|
468 if (aug[0] == 'L')
|
|
|
469 {
|
|
|
470 fs->lsda_encoding = *p++;
|
|
|
471 aug += 1;
|
|
|
472 }
|
|
|
473
|
|
|
474 /* "R" indicates a byte indicating how FDE addresses are encoded. */
|
|
|
475 else if (aug[0] == 'R')
|
|
|
476 {
|
|
|
477 fs->fde_encoding = *p++;
|
|
|
478 aug += 1;
|
|
|
479 }
|
|
|
480
|
|
|
481 /* "P" indicates a personality routine in the CIE augmentation. */
|
|
|
482 else if (aug[0] == 'P')
|
|
|
483 {
|
|
|
484 _Unwind_Ptr personality;
|
|
|
485
|
|
|
486 p = read_encoded_value (context, *p, p + 1, &personality);
|
|
|
487 fs->personality = (_Unwind_Personality_Fn) personality;
|
|
|
488 aug += 1;
|
|
|
489 }
|
|
|
490
|
|
|
491 /* "S" indicates a signal frame. */
|
|
|
492 else if (aug[0] == 'S')
|
|
|
493 {
|
|
|
494 fs->signal_frame = 1;
|
|
|
495 aug += 1;
|
|
|
496 }
|
|
|
497
|
|
|
498 /* Otherwise we have an unknown augmentation string.
|
|
|
499 Bail unless we saw a 'z' prefix. */
|
|
|
500 else
|
|
|
501 return ret;
|
|
|
502 }
|
|
|
503
|
|
|
504 return ret ? ret : p;
|
|
|
505 }
|
|
|
506
|
|
|
507
|
|
|
508 /* Decode a DW_OP stack program. Return the top of stack. Push INITIAL
|
|
|
509 onto the stack to start. */
|
|
|
510
|
|
|
511 static _Unwind_Word
|
|
|
512 execute_stack_op (const unsigned char *op_ptr, const unsigned char *op_end,
|
|
|
513 struct _Unwind_Context *context, _Unwind_Word initial)
|
|
|
514 {
|
|
|
515 _Unwind_Word stack[64]; /* ??? Assume this is enough. */
|
|
|
516 int stack_elt;
|
|
|
517
|
|
|
518 stack[0] = initial;
|
|
|
519 stack_elt = 1;
|
|
|
520
|
|
|
521 while (op_ptr < op_end)
|
|
|
522 {
|
|
|
523 enum dwarf_location_atom op = *op_ptr++;
|
|
|
524 _Unwind_Word result;
|
|
|
525 _uleb128_t reg, utmp;
|
|
|
526 _sleb128_t offset, stmp;
|
|
|
527
|
|
|
528 switch (op)
|
|
|
529 {
|
|
|
530 case DW_OP_lit0:
|
|
|
531 case DW_OP_lit1:
|
|
|
532 case DW_OP_lit2:
|
|
|
533 case DW_OP_lit3:
|
|
|
534 case DW_OP_lit4:
|
|
|
535 case DW_OP_lit5:
|
|
|
536 case DW_OP_lit6:
|
|
|
537 case DW_OP_lit7:
|
|
|
538 case DW_OP_lit8:
|
|
|
539 case DW_OP_lit9:
|
|
|
540 case DW_OP_lit10:
|
|
|
541 case DW_OP_lit11:
|
|
|
542 case DW_OP_lit12:
|
|
|
543 case DW_OP_lit13:
|
|
|
544 case DW_OP_lit14:
|
|
|
545 case DW_OP_lit15:
|
|
|
546 case DW_OP_lit16:
|
|
|
547 case DW_OP_lit17:
|
|
|
548 case DW_OP_lit18:
|
|
|
549 case DW_OP_lit19:
|
|
|
550 case DW_OP_lit20:
|
|
|
551 case DW_OP_lit21:
|
|
|
552 case DW_OP_lit22:
|
|
|
553 case DW_OP_lit23:
|
|
|
554 case DW_OP_lit24:
|
|
|
555 case DW_OP_lit25:
|
|
|
556 case DW_OP_lit26:
|
|
|
557 case DW_OP_lit27:
|
|
|
558 case DW_OP_lit28:
|
|
|
559 case DW_OP_lit29:
|
|
|
560 case DW_OP_lit30:
|
|
|
561 case DW_OP_lit31:
|
|
|
562 result = op - DW_OP_lit0;
|
|
|
563 break;
|
|
|
564
|
|
|
565 case DW_OP_addr:
|
|
|
566 result = (_Unwind_Word) (_Unwind_Ptr) read_pointer (op_ptr);
|
|
|
567 op_ptr += sizeof (void *);
|
|
|
568 break;
|
|
|
569
|
|
|
570 case DW_OP_GNU_encoded_addr:
|
|
|
571 {
|
|
|
572 _Unwind_Ptr presult;
|
|
|
573 op_ptr = read_encoded_value (context, *op_ptr, op_ptr+1, &presult);
|
|
|
574 result = presult;
|
|
|
575 }
|
|
|
576 break;
|
|
|
577
|
|
|
578 case DW_OP_const1u:
|
|
|
579 result = read_1u (op_ptr);
|
|
|
580 op_ptr += 1;
|
|
|
581 break;
|
|
|
582 case DW_OP_const1s:
|
|
|
583 result = read_1s (op_ptr);
|
|
|
584 op_ptr += 1;
|
|
|
585 break;
|
|
|
586 case DW_OP_const2u:
|
|
|
587 result = read_2u (op_ptr);
|
|
|
588 op_ptr += 2;
|
|
|
589 break;
|
|
|
590 case DW_OP_const2s:
|
|
|
591 result = read_2s (op_ptr);
|
|
|
592 op_ptr += 2;
|
|
|
593 break;
|
|
|
594 case DW_OP_const4u:
|
|
|
595 result = read_4u (op_ptr);
|
|
|
596 op_ptr += 4;
|
|
|
597 break;
|
|
|
598 case DW_OP_const4s:
|
|
|
599 result = read_4s (op_ptr);
|
|
|
600 op_ptr += 4;
|
|
|
601 break;
|
|
|
602 case DW_OP_const8u:
|
|
|
603 result = read_8u (op_ptr);
|
|
|
604 op_ptr += 8;
|
|
|
605 break;
|
|
|
606 case DW_OP_const8s:
|
|
|
607 result = read_8s (op_ptr);
|
|
|
608 op_ptr += 8;
|
|
|
609 break;
|
|
|
610 case DW_OP_constu:
|
|
|
611 op_ptr = read_uleb128 (op_ptr, &utmp);
|
|
|
612 result = (_Unwind_Word)utmp;
|
|
|
613 break;
|
|
|
614 case DW_OP_consts:
|
|
|
615 op_ptr = read_sleb128 (op_ptr, &stmp);
|
|
|
616 result = (_Unwind_Sword)stmp;
|
|
|
617 break;
|
|
|
618
|
|
|
619 case DW_OP_reg0:
|
|
|
620 case DW_OP_reg1:
|
|
|
621 case DW_OP_reg2:
|
|
|
622 case DW_OP_reg3:
|
|
|
623 case DW_OP_reg4:
|
|
|
624 case DW_OP_reg5:
|
|
|
625 case DW_OP_reg6:
|
|
|
626 case DW_OP_reg7:
|
|
|
627 case DW_OP_reg8:
|
|
|
628 case DW_OP_reg9:
|
|
|
629 case DW_OP_reg10:
|
|
|
630 case DW_OP_reg11:
|
|
|
631 case DW_OP_reg12:
|
|
|
632 case DW_OP_reg13:
|
|
|
633 case DW_OP_reg14:
|
|
|
634 case DW_OP_reg15:
|
|
|
635 case DW_OP_reg16:
|
|
|
636 case DW_OP_reg17:
|
|
|
637 case DW_OP_reg18:
|
|
|
638 case DW_OP_reg19:
|
|
|
639 case DW_OP_reg20:
|
|
|
640 case DW_OP_reg21:
|
|
|
641 case DW_OP_reg22:
|
|
|
642 case DW_OP_reg23:
|
|
|
643 case DW_OP_reg24:
|
|
|
644 case DW_OP_reg25:
|
|
|
645 case DW_OP_reg26:
|
|
|
646 case DW_OP_reg27:
|
|
|
647 case DW_OP_reg28:
|
|
|
648 case DW_OP_reg29:
|
|
|
649 case DW_OP_reg30:
|
|
|
650 case DW_OP_reg31:
|
|
|
651 result = _Unwind_GetGR (context, op - DW_OP_reg0);
|
|
|
652 break;
|
|
|
653 case DW_OP_regx:
|
|
|
654 op_ptr = read_uleb128 (op_ptr, ®);
|
|
|
655 result = _Unwind_GetGR (context, reg);
|
|
|
656 break;
|
|
|
657
|
|
|
658 case DW_OP_breg0:
|
|
|
659 case DW_OP_breg1:
|
|
|
660 case DW_OP_breg2:
|
|
|
661 case DW_OP_breg3:
|
|
|
662 case DW_OP_breg4:
|
|
|
663 case DW_OP_breg5:
|
|
|
664 case DW_OP_breg6:
|
|
|
665 case DW_OP_breg7:
|
|
|
666 case DW_OP_breg8:
|
|
|
667 case DW_OP_breg9:
|
|
|
668 case DW_OP_breg10:
|
|
|
669 case DW_OP_breg11:
|
|
|
670 case DW_OP_breg12:
|
|
|
671 case DW_OP_breg13:
|
|
|
672 case DW_OP_breg14:
|
|
|
673 case DW_OP_breg15:
|
|
|
674 case DW_OP_breg16:
|
|
|
675 case DW_OP_breg17:
|
|
|
676 case DW_OP_breg18:
|
|
|
677 case DW_OP_breg19:
|
|
|
678 case DW_OP_breg20:
|
|
|
679 case DW_OP_breg21:
|
|
|
680 case DW_OP_breg22:
|
|
|
681 case DW_OP_breg23:
|
|
|
682 case DW_OP_breg24:
|
|
|
683 case DW_OP_breg25:
|
|
|
684 case DW_OP_breg26:
|
|
|
685 case DW_OP_breg27:
|
|
|
686 case DW_OP_breg28:
|
|
|
687 case DW_OP_breg29:
|
|
|
688 case DW_OP_breg30:
|
|
|
689 case DW_OP_breg31:
|
|
|
690 op_ptr = read_sleb128 (op_ptr, &offset);
|
|
|
691 result = _Unwind_GetGR (context, op - DW_OP_breg0) + offset;
|
|
|
692 break;
|
|
|
693 case DW_OP_bregx:
|
|
|
694 op_ptr = read_uleb128 (op_ptr, ®);
|
|
|
695 op_ptr = read_sleb128 (op_ptr, &offset);
|
|
|
696 result = _Unwind_GetGR (context, reg) + (_Unwind_Word)offset;
|
|
|
697 break;
|
|
|
698
|
|
|
699 case DW_OP_dup:
|
|
|
700 gcc_assert (stack_elt);
|
|
|
701 result = stack[stack_elt - 1];
|
|
|
702 break;
|
|
|
703
|
|
|
704 case DW_OP_drop:
|
|
|
705 gcc_assert (stack_elt);
|
|
|
706 stack_elt -= 1;
|
|
|
707 goto no_push;
|
|
|
708
|
|
|
709 case DW_OP_pick:
|
|
|
710 offset = *op_ptr++;
|
|
|
711 gcc_assert (offset < stack_elt - 1);
|
|
|
712 result = stack[stack_elt - 1 - offset];
|
|
|
713 break;
|
|
|
714
|
|
|
715 case DW_OP_over:
|
|
|
716 gcc_assert (stack_elt >= 2);
|
|
|
717 result = stack[stack_elt - 2];
|
|
|
718 break;
|
|
|
719
|
|
|
720 case DW_OP_swap:
|
|
|
721 {
|
|
|
722 _Unwind_Word t;
|
|
|
723 gcc_assert (stack_elt >= 2);
|
|
|
724 t = stack[stack_elt - 1];
|
|
|
725 stack[stack_elt - 1] = stack[stack_elt - 2];
|
|
|
726 stack[stack_elt - 2] = t;
|
|
|
727 goto no_push;
|
|
|
728 }
|
|
|
729
|
|
|
730 case DW_OP_rot:
|
|
|
731 {
|
|
|
732 _Unwind_Word t1, t2, t3;
|
|
|
733
|
|
|
734 gcc_assert (stack_elt >= 3);
|
|
|
735 t1 = stack[stack_elt - 1];
|
|
|
736 t2 = stack[stack_elt - 2];
|
|
|
737 t3 = stack[stack_elt - 3];
|
|
|
738 stack[stack_elt - 1] = t2;
|
|
|
739 stack[stack_elt - 2] = t3;
|
|
|
740 stack[stack_elt - 3] = t1;
|
|
|
741 goto no_push;
|
|
|
742 }
|
|
|
743
|
|
|
744 case DW_OP_deref:
|
|
|
745 case DW_OP_deref_size:
|
|
|
746 case DW_OP_abs:
|
|
|
747 case DW_OP_neg:
|
|
|
748 case DW_OP_not:
|
|
|
749 case DW_OP_plus_uconst:
|
|
|
750 /* Unary operations. */
|
|
|
751 gcc_assert (stack_elt);
|
|
|
752 stack_elt -= 1;
|
|
|
753
|
|
|
754 result = stack[stack_elt];
|
|
|
755
|
|
|
756 switch (op)
|
|
|
757 {
|
|
|
758 case DW_OP_deref:
|
|
|
759 {
|
|
|
760 void *ptr = (void *) (_Unwind_Ptr) result;
|
|
|
761 result = (_Unwind_Ptr) read_pointer (ptr);
|
|
|
762 }
|
|
|
763 break;
|
|
|
764
|
|
|
765 case DW_OP_deref_size:
|
|
|
766 {
|
|
|
767 void *ptr = (void *) (_Unwind_Ptr) result;
|
|
|
768 switch (*op_ptr++)
|
|
|
769 {
|
|
|
770 case 1:
|
|
|
771 result = read_1u (ptr);
|
|
|
772 break;
|
|
|
773 case 2:
|
|
|
774 result = read_2u (ptr);
|
|
|
775 break;
|
|
|
776 case 4:
|
|
|
777 result = read_4u (ptr);
|
|
|
778 break;
|
|
|
779 case 8:
|
|
|
780 result = read_8u (ptr);
|
|
|
781 break;
|
|
|
782 default:
|
|
|
783 gcc_unreachable ();
|
|
|
784 }
|
|
|
785 }
|
|
|
786 break;
|
|
|
787
|
|
|
788 case DW_OP_abs:
|
|
|
789 if ((_Unwind_Sword) result < 0)
|
|
|
790 result = -result;
|
|
|
791 break;
|
|
|
792 case DW_OP_neg:
|
|
|
793 result = -result;
|
|
|
794 break;
|
|
|
795 case DW_OP_not:
|
|
|
796 result = ~result;
|
|
|
797 break;
|
|
|
798 case DW_OP_plus_uconst:
|
|
|
799 op_ptr = read_uleb128 (op_ptr, &utmp);
|
|
|
800 result += (_Unwind_Word)utmp;
|
|
|
801 break;
|
|
|
802
|
|
|
803 default:
|
|
|
804 gcc_unreachable ();
|
|
|
805 }
|
|
|
806 break;
|
|
|
807
|
|
|
808 case DW_OP_and:
|
|
|
809 case DW_OP_div:
|
|
|
810 case DW_OP_minus:
|
|
|
811 case DW_OP_mod:
|
|
|
812 case DW_OP_mul:
|
|
|
813 case DW_OP_or:
|
|
|
814 case DW_OP_plus:
|
|
|
815 case DW_OP_shl:
|
|
|
816 case DW_OP_shr:
|
|
|
817 case DW_OP_shra:
|
|
|
818 case DW_OP_xor:
|
|
|
819 case DW_OP_le:
|
|
|
820 case DW_OP_ge:
|
|
|
821 case DW_OP_eq:
|
|
|
822 case DW_OP_lt:
|
|
|
823 case DW_OP_gt:
|
|
|
824 case DW_OP_ne:
|
|
|
825 {
|
|
|
826 /* Binary operations. */
|
|
|
827 _Unwind_Word first, second;
|
|
|
828 gcc_assert (stack_elt >= 2);
|
|
|
829 stack_elt -= 2;
|
|
|
830
|
|
|
831 second = stack[stack_elt];
|
|
|
832 first = stack[stack_elt + 1];
|
|
|
833
|
|
|
834 switch (op)
|
|
|
835 {
|
|
|
836 case DW_OP_and:
|
|
|
837 result = second & first;
|
|
|
838 break;
|
|
|
839 case DW_OP_div:
|
|
|
840 result = (_Unwind_Sword) second / (_Unwind_Sword) first;
|
|
|
841 break;
|
|
|
842 case DW_OP_minus:
|
|
|
843 result = second - first;
|
|
|
844 break;
|
|
|
845 case DW_OP_mod:
|
|
|
846 result = second % first;
|
|
|
847 break;
|
|
|
848 case DW_OP_mul:
|
|
|
849 result = second * first;
|
|
|
850 break;
|
|
|
851 case DW_OP_or:
|
|
|
852 result = second | first;
|
|
|
853 break;
|
|
|
854 case DW_OP_plus:
|
|
|
855 result = second + first;
|
|
|
856 break;
|
|
|
857 case DW_OP_shl:
|
|
|
858 result = second << first;
|
|
|
859 break;
|
|
|
860 case DW_OP_shr:
|
|
|
861 result = second >> first;
|
|
|
862 break;
|
|
|
863 case DW_OP_shra:
|
|
|
864 result = (_Unwind_Sword) second >> first;
|
|
|
865 break;
|
|
|
866 case DW_OP_xor:
|
|
|
867 result = second ^ first;
|
|
|
868 break;
|
|
|
869 case DW_OP_le:
|
|
|
870 result = (_Unwind_Sword) second <= (_Unwind_Sword) first;
|
|
|
871 break;
|
|
|
872 case DW_OP_ge:
|
|
|
873 result = (_Unwind_Sword) second >= (_Unwind_Sword) first;
|
|
|
874 break;
|
|
|
875 case DW_OP_eq:
|
|
|
876 result = (_Unwind_Sword) second == (_Unwind_Sword) first;
|
|
|
877 break;
|
|
|
878 case DW_OP_lt:
|
|
|
879 result = (_Unwind_Sword) second < (_Unwind_Sword) first;
|
|
|
880 break;
|
|
|
881 case DW_OP_gt:
|
|
|
882 result = (_Unwind_Sword) second > (_Unwind_Sword) first;
|
|
|
883 break;
|
|
|
884 case DW_OP_ne:
|
|
|
885 result = (_Unwind_Sword) second != (_Unwind_Sword) first;
|
|
|
886 break;
|
|
|
887
|
|
|
888 default:
|
|
|
889 gcc_unreachable ();
|
|
|
890 }
|
|
|
891 }
|
|
|
892 break;
|
|
|
893
|
|
|
894 case DW_OP_skip:
|
|
|
895 offset = read_2s (op_ptr);
|
|
|
896 op_ptr += 2;
|
|
|
897 op_ptr += offset;
|
|
|
898 goto no_push;
|
|
|
899
|
|
|
900 case DW_OP_bra:
|
|
|
901 gcc_assert (stack_elt);
|
|
|
902 stack_elt -= 1;
|
|
|
903
|
|
|
904 offset = read_2s (op_ptr);
|
|
|
905 op_ptr += 2;
|
|
|
906 if (stack[stack_elt] != 0)
|
|
|
907 op_ptr += offset;
|
|
|
908 goto no_push;
|
|
|
909
|
|
|
910 case DW_OP_nop:
|
|
|
911 goto no_push;
|
|
|
912
|
|
|
913 default:
|
|
|
914 gcc_unreachable ();
|
|
|
915 }
|
|
|
916
|
|
|
917 /* Most things push a result value. */
|
|
|
918 gcc_assert ((size_t) stack_elt < sizeof(stack)/sizeof(*stack));
|
|
|
919 stack[stack_elt++] = result;
|
|
|
920 no_push:;
|
|
|
921 }
|
|
|
922
|
|
|
923 /* We were executing this program to get a value. It should be
|
|
|
924 at top of stack. */
|
|
|
925 gcc_assert (stack_elt);
|
|
|
926 stack_elt -= 1;
|
|
|
927 return stack[stack_elt];
|
|
|
928 }
|
|
|
929
|
|
|
930
|
|
|
931 /* Decode DWARF 2 call frame information. Takes pointers the
|
|
|
932 instruction sequence to decode, current register information and
|
|
|
933 CIE info, and the PC range to evaluate. */
|
|
|
934
|
|
|
935 static void
|
|
|
936 execute_cfa_program (const unsigned char *insn_ptr,
|
|
|
937 const unsigned char *insn_end,
|
|
|
938 struct _Unwind_Context *context,
|
|
|
939 _Unwind_FrameState *fs)
|
|
|
940 {
|
|
|
941 struct frame_state_reg_info *unused_rs = NULL;
|
|
|
942
|
|
|
943 /* Don't allow remember/restore between CIE and FDE programs. */
|
|
|
944 fs->regs.prev = NULL;
|
|
|
945
|
|
|
946 /* The comparison with the return address uses < rather than <= because
|
|
|
947 we are only interested in the effects of code before the call; for a
|
|
|
948 noreturn function, the return address may point to unrelated code with
|
|
|
949 a different stack configuration that we are not interested in. We
|
|
|
950 assume that the call itself is unwind info-neutral; if not, or if
|
|
|
951 there are delay instructions that adjust the stack, these must be
|
|
|
952 reflected at the point immediately before the call insn.
|
|
|
953 In signal frames, return address is after last completed instruction,
|
|
|
954 so we add 1 to return address to make the comparison <=. */
|
|
|
955 while (insn_ptr < insn_end
|
|
|
956 && fs->pc < context->ra + _Unwind_IsSignalFrame (context))
|
|
|
957 {
|
|
|
958 unsigned char insn = *insn_ptr++;
|
|
|
959 _uleb128_t reg, utmp;
|
|
|
960 _sleb128_t offset, stmp;
|
|
|
961
|
|
|
962 if ((insn & 0xc0) == DW_CFA_advance_loc)
|
|
|
963 fs->pc += (insn & 0x3f) * fs->code_align;
|
|
|
964 else if ((insn & 0xc0) == DW_CFA_offset)
|
|
|
965 {
|
|
|
966 reg = insn & 0x3f;
|
|
|
967 insn_ptr = read_uleb128 (insn_ptr, &utmp);
|
|
|
968 offset = (_Unwind_Sword) utmp * fs->data_align;
|
|
|
969 reg = DWARF_REG_TO_UNWIND_COLUMN (reg);
|
|
|
970 if (UNWIND_COLUMN_IN_RANGE (reg))
|
|
|
971 {
|
|
|
972 fs->regs.reg[reg].how = REG_SAVED_OFFSET;
|
|
|
973 fs->regs.reg[reg].loc.offset = offset;
|
|
|
974 }
|
|
|
975 }
|
|
|
976 else if ((insn & 0xc0) == DW_CFA_restore)
|
|
|
977 {
|
|
|
978 reg = insn & 0x3f;
|
|
|
979 reg = DWARF_REG_TO_UNWIND_COLUMN (reg);
|
|
|
980 if (UNWIND_COLUMN_IN_RANGE (reg))
|
|
|
981 fs->regs.reg[reg].how = REG_UNSAVED;
|
|
|
982 }
|
|
|
983 else switch (insn)
|
|
|
984 {
|
|
|
985 case DW_CFA_set_loc:
|
|
|
986 {
|
|
|
987 _Unwind_Ptr pc;
|
|
|
988
|
|
|
989 insn_ptr = read_encoded_value (context, fs->fde_encoding,
|
|
|
990 insn_ptr, &pc);
|
|
|
991 fs->pc = (void *) pc;
|
|
|
992 }
|
|
|
993 break;
|
|
|
994
|
|
|
995 case DW_CFA_advance_loc1:
|
|
|
996 fs->pc += read_1u (insn_ptr) * fs->code_align;
|
|
|
997 insn_ptr += 1;
|
|
|
998 break;
|
|
|
999 case DW_CFA_advance_loc2:
|
|
|
1000 fs->pc += read_2u (insn_ptr) * fs->code_align;
|
|
|
1001 insn_ptr += 2;
|
|
|
1002 break;
|
|
|
1003 case DW_CFA_advance_loc4:
|
|
|
1004 fs->pc += read_4u (insn_ptr) * fs->code_align;
|
|
|
1005 insn_ptr += 4;
|
|
|
1006 break;
|
|
|
1007
|
|
|
1008 case DW_CFA_offset_extended:
|
|
|
1009 insn_ptr = read_uleb128 (insn_ptr, ®);
|
|
|
1010 insn_ptr = read_uleb128 (insn_ptr, &utmp);
|
|
|
1011 offset = (_Unwind_Sword) utmp * fs->data_align;
|
|
|
1012 reg = DWARF_REG_TO_UNWIND_COLUMN (reg);
|
|
|
1013 if (UNWIND_COLUMN_IN_RANGE (reg))
|
|
|
1014 {
|
|
|
1015 fs->regs.reg[reg].how = REG_SAVED_OFFSET;
|
|
|
1016 fs->regs.reg[reg].loc.offset = offset;
|
|
|
1017 }
|
|
|
1018 break;
|
|
|
1019
|
|
|
1020 case DW_CFA_restore_extended:
|
|
|
1021 insn_ptr = read_uleb128 (insn_ptr, ®);
|
|
|
1022 /* FIXME, this is wrong; the CIE might have said that the
|
|
|
1023 register was saved somewhere. */
|
|
|
1024 reg = DWARF_REG_TO_UNWIND_COLUMN (reg);
|
|
|
1025 if (UNWIND_COLUMN_IN_RANGE (reg))
|
|
|
1026 fs->regs.reg[reg].how = REG_UNSAVED;
|
|
|
1027 break;
|
|
|
1028
|
|
|
1029 case DW_CFA_same_value:
|
|
|
1030 insn_ptr = read_uleb128 (insn_ptr, ®);
|
|
|
1031 reg = DWARF_REG_TO_UNWIND_COLUMN (reg);
|
|
|
1032 if (UNWIND_COLUMN_IN_RANGE (reg))
|
|
|
1033 fs->regs.reg[reg].how = REG_UNSAVED;
|
|
|
1034 break;
|
|
|
1035
|
|
|
1036 case DW_CFA_undefined:
|
|
|
1037 insn_ptr = read_uleb128 (insn_ptr, ®);
|
|
|
1038 reg = DWARF_REG_TO_UNWIND_COLUMN (reg);
|
|
|
1039 if (UNWIND_COLUMN_IN_RANGE (reg))
|
|
|
1040 fs->regs.reg[reg].how = REG_UNDEFINED;
|
|
|
1041 break;
|
|
|
1042
|
|
|
1043 case DW_CFA_nop:
|
|
|
1044 break;
|
|
|
1045
|
|
|
1046 case DW_CFA_register:
|
|
|
1047 {
|
|
|
1048 _uleb128_t reg2;
|
|
|
1049 insn_ptr = read_uleb128 (insn_ptr, ®);
|
|
|
1050 insn_ptr = read_uleb128 (insn_ptr, ®2);
|
|
|
1051 reg = DWARF_REG_TO_UNWIND_COLUMN (reg);
|
|
|
1052 if (UNWIND_COLUMN_IN_RANGE (reg))
|
|
|
1053 {
|
|
|
1054 fs->regs.reg[reg].how = REG_SAVED_REG;
|
|
|
1055 fs->regs.reg[reg].loc.reg = (_Unwind_Word)reg2;
|
|
|
1056 }
|
|
|
1057 }
|
|
|
1058 break;
|
|
|
1059
|
|
|
1060 case DW_CFA_remember_state:
|
|
|
1061 {
|
|
|
1062 struct frame_state_reg_info *new_rs;
|
|
|
1063 if (unused_rs)
|
|
|
1064 {
|
|
|
1065 new_rs = unused_rs;
|
|
|
1066 unused_rs = unused_rs->prev;
|
|
|
1067 }
|
|
|
1068 else
|
|
|
1069 new_rs = alloca (sizeof (struct frame_state_reg_info));
|
|
|
1070
|
|
|
1071 *new_rs = fs->regs;
|
|
|
1072 fs->regs.prev = new_rs;
|
|
|
1073 }
|
|
|
1074 break;
|
|
|
1075
|
|
|
1076 case DW_CFA_restore_state:
|
|
|
1077 {
|
|
|
1078 struct frame_state_reg_info *old_rs = fs->regs.prev;
|
|
|
1079 fs->regs = *old_rs;
|
|
|
1080 old_rs->prev = unused_rs;
|
|
|
1081 unused_rs = old_rs;
|
|
|
1082 }
|
|
|
1083 break;
|
|
|
1084
|
|
|
1085 case DW_CFA_def_cfa:
|
|
|
1086 insn_ptr = read_uleb128 (insn_ptr, &utmp);
|
|
|
1087 fs->regs.cfa_reg = (_Unwind_Word)utmp;
|
|
|
1088 insn_ptr = read_uleb128 (insn_ptr, &utmp);
|
|
|
1089 fs->regs.cfa_offset = (_Unwind_Word)utmp;
|
|
|
1090 fs->regs.cfa_how = CFA_REG_OFFSET;
|
|
|
1091 break;
|
|
|
1092
|
|
|
1093 case DW_CFA_def_cfa_register:
|
|
|
1094 insn_ptr = read_uleb128 (insn_ptr, &utmp);
|
|
|
1095 fs->regs.cfa_reg = (_Unwind_Word)utmp;
|
|
|
1096 fs->regs.cfa_how = CFA_REG_OFFSET;
|
|
|
1097 break;
|
|
|
1098
|
|
|
1099 case DW_CFA_def_cfa_offset:
|
|
|
1100 insn_ptr = read_uleb128 (insn_ptr, &utmp);
|
|
|
1101 fs->regs.cfa_offset = utmp;
|
|
|
1102 /* cfa_how deliberately not set. */
|
|
|
1103 break;
|
|
|
1104
|
|
|
1105 case DW_CFA_def_cfa_expression:
|
|
|
1106 fs->regs.cfa_exp = insn_ptr;
|
|
|
1107 fs->regs.cfa_how = CFA_EXP;
|
|
|
1108 insn_ptr = read_uleb128 (insn_ptr, &utmp);
|
|
|
1109 insn_ptr += utmp;
|
|
|
1110 break;
|
|
|
1111
|
|
|
1112 case DW_CFA_expression:
|
|
|
1113 insn_ptr = read_uleb128 (insn_ptr, ®);
|
|
|
1114 reg = DWARF_REG_TO_UNWIND_COLUMN (reg);
|
|
|
1115 if (UNWIND_COLUMN_IN_RANGE (reg))
|
|
|
1116 {
|
|
|
1117 fs->regs.reg[reg].how = REG_SAVED_EXP;
|
|
|
1118 fs->regs.reg[reg].loc.exp = insn_ptr;
|
|
|
1119 }
|
|
|
1120 insn_ptr = read_uleb128 (insn_ptr, &utmp);
|
|
|
1121 insn_ptr += utmp;
|
|
|
1122 break;
|
|
|
1123
|
|
|
1124 /* Dwarf3. */
|
|
|
1125 case DW_CFA_offset_extended_sf:
|
|
|
1126 insn_ptr = read_uleb128 (insn_ptr, ®);
|
|
|
1127 insn_ptr = read_sleb128 (insn_ptr, &stmp);
|
|
|
1128 offset = stmp * fs->data_align;
|
|
|
1129 reg = DWARF_REG_TO_UNWIND_COLUMN (reg);
|
|
|
1130 if (UNWIND_COLUMN_IN_RANGE (reg))
|
|
|
1131 {
|
|
|
1132 fs->regs.reg[reg].how = REG_SAVED_OFFSET;
|
|
|
1133 fs->regs.reg[reg].loc.offset = offset;
|
|
|
1134 }
|
|
|
1135 break;
|
|
|
1136
|
|
|
1137 case DW_CFA_def_cfa_sf:
|
|
|
1138 insn_ptr = read_uleb128 (insn_ptr, &utmp);
|
|
|
1139 fs->regs.cfa_reg = (_Unwind_Word)utmp;
|
|
|
1140 insn_ptr = read_sleb128 (insn_ptr, &stmp);
|
|
|
1141 fs->regs.cfa_offset = (_Unwind_Sword)stmp;
|
|
|
1142 fs->regs.cfa_how = CFA_REG_OFFSET;
|
|
|
1143 fs->regs.cfa_offset *= fs->data_align;
|
|
|
1144 break;
|
|
|
1145
|
|
|
1146 case DW_CFA_def_cfa_offset_sf:
|
|
|
1147 insn_ptr = read_sleb128 (insn_ptr, &stmp);
|
|
|
1148 fs->regs.cfa_offset = (_Unwind_Sword)stmp;
|
|
|
1149 fs->regs.cfa_offset *= fs->data_align;
|
|
|
1150 /* cfa_how deliberately not set. */
|
|
|
1151 break;
|
|
|
1152
|
|
|
1153 case DW_CFA_val_offset:
|
|
|
1154 insn_ptr = read_uleb128 (insn_ptr, ®);
|
|
|
1155 insn_ptr = read_uleb128 (insn_ptr, &utmp);
|
|
|
1156 offset = (_Unwind_Sword) utmp * fs->data_align;
|
|
|
1157 reg = DWARF_REG_TO_UNWIND_COLUMN (reg);
|
|
|
1158 if (UNWIND_COLUMN_IN_RANGE (reg))
|
|
|
1159 {
|
|
|
1160 fs->regs.reg[reg].how = REG_SAVED_VAL_OFFSET;
|
|
|
1161 fs->regs.reg[reg].loc.offset = offset;
|
|
|
1162 }
|
|
|
1163 break;
|
|
|
1164
|
|
|
1165 case DW_CFA_val_offset_sf:
|
|
|
1166 insn_ptr = read_uleb128 (insn_ptr, ®);
|
|
|
1167 insn_ptr = read_sleb128 (insn_ptr, &stmp);
|
|
|
1168 offset = stmp * fs->data_align;
|
|
|
1169 reg = DWARF_REG_TO_UNWIND_COLUMN (reg);
|
|
|
1170 if (UNWIND_COLUMN_IN_RANGE (reg))
|
|
|
1171 {
|
|
|
1172 fs->regs.reg[reg].how = REG_SAVED_VAL_OFFSET;
|
|
|
1173 fs->regs.reg[reg].loc.offset = offset;
|
|
|
1174 }
|
|
|
1175 break;
|
|
|
1176
|
|
|
1177 case DW_CFA_val_expression:
|
|
|
1178 insn_ptr = read_uleb128 (insn_ptr, ®);
|
|
|
1179 reg = DWARF_REG_TO_UNWIND_COLUMN (reg);
|
|
|
1180 if (UNWIND_COLUMN_IN_RANGE (reg))
|
|
|
1181 {
|
|
|
1182 fs->regs.reg[reg].how = REG_SAVED_VAL_EXP;
|
|
|
1183 fs->regs.reg[reg].loc.exp = insn_ptr;
|
|
|
1184 }
|
|
|
1185 insn_ptr = read_uleb128 (insn_ptr, &utmp);
|
|
|
1186 insn_ptr += utmp;
|
|
|
1187 break;
|
|
|
1188
|
|
|
1189 case DW_CFA_GNU_window_save:
|
|
|
1190 #if defined (__aarch64__) && !defined (__ILP32__)
|
|
|
1191 /* This CFA is multiplexed with Sparc. On AArch64 it's used to toggle
|
|
|
1192 return address signing status. */
|
|
|
1193 fs->regs.reg[DWARF_REGNUM_AARCH64_RA_STATE].loc.offset ^= 1;
|
|
|
1194 #else
|
|
|
1195 /* ??? Hardcoded for SPARC register window configuration. */
|
|
|
1196 if (__LIBGCC_DWARF_FRAME_REGISTERS__ >= 32)
|
|
|
1197 for (reg = 16; reg < 32; ++reg)
|
|
|
1198 {
|
|
|
1199 fs->regs.reg[reg].how = REG_SAVED_OFFSET;
|
|
|
1200 fs->regs.reg[reg].loc.offset = (reg - 16) * sizeof (void *);
|
|
|
1201 }
|
|
|
1202 #endif
|
|
|
1203 break;
|
|
|
1204
|
|
|
1205 case DW_CFA_GNU_args_size:
|
|
|
1206 insn_ptr = read_uleb128 (insn_ptr, &utmp);
|
|
|
1207 context->args_size = (_Unwind_Word)utmp;
|
|
|
1208 break;
|
|
|
1209
|
|
|
1210 case DW_CFA_GNU_negative_offset_extended:
|
|
|
1211 /* Obsoleted by DW_CFA_offset_extended_sf, but used by
|
|
|
1212 older PowerPC code. */
|
|
|
1213 insn_ptr = read_uleb128 (insn_ptr, ®);
|
|
|
1214 insn_ptr = read_uleb128 (insn_ptr, &utmp);
|
|
|
1215 offset = (_Unwind_Word) utmp * fs->data_align;
|
|
|
1216 reg = DWARF_REG_TO_UNWIND_COLUMN (reg);
|
|
|
1217 if (UNWIND_COLUMN_IN_RANGE (reg))
|
|
|
1218 {
|
|
|
1219 fs->regs.reg[reg].how = REG_SAVED_OFFSET;
|
|
|
1220 fs->regs.reg[reg].loc.offset = -offset;
|
|
|
1221 }
|
|
|
1222 break;
|
|
|
1223
|
|
|
1224 default:
|
|
|
1225 gcc_unreachable ();
|
|
|
1226 }
|
|
|
1227 }
|
|
|
1228 }
|
|
|
1229
|
|
|
1230 /* Given the _Unwind_Context CONTEXT for a stack frame, look up the FDE for
|
|
|
1231 its caller and decode it into FS. This function also sets the
|
|
|
1232 args_size and lsda members of CONTEXT, as they are really information
|
|
|
1233 about the caller's frame. */
|
|
|
1234
|
|
|
1235 static _Unwind_Reason_Code
|
|
|
1236 uw_frame_state_for (struct _Unwind_Context *context, _Unwind_FrameState *fs)
|
|
|
1237 {
|
|
|
1238 const struct dwarf_fde *fde;
|
|
|
1239 const struct dwarf_cie *cie;
|
|
|
1240 const unsigned char *aug, *insn, *end;
|
|
|
1241
|
|
|
1242 memset (fs, 0, sizeof (*fs));
|
|
|
1243 context->args_size = 0;
|
|
|
1244 context->lsda = 0;
|
|
|
1245
|
|
|
1246 if (context->ra == 0)
|
|
|
1247 return _URC_END_OF_STACK;
|
|
|
1248
|
|
|
1249 fde = _Unwind_Find_FDE (context->ra + _Unwind_IsSignalFrame (context) - 1,
|
|
|
1250 &context->bases);
|
|
|
1251 if (fde == NULL)
|
|
|
1252 {
|
|
|
1253 #ifdef MD_FALLBACK_FRAME_STATE_FOR
|
|
|
1254 /* Couldn't find frame unwind info for this function. Try a
|
|
|
1255 target-specific fallback mechanism. This will necessarily
|
|
|
1256 not provide a personality routine or LSDA. */
|
|
|
1257 return MD_FALLBACK_FRAME_STATE_FOR (context, fs);
|
|
|
1258 #else
|
|
|
1259 return _URC_END_OF_STACK;
|
|
|
1260 #endif
|
|
|
1261 }
|
|
|
1262
|
|
|
1263 fs->pc = context->bases.func;
|
|
|
1264
|
|
|
1265 cie = get_cie (fde);
|
|
|
1266 insn = extract_cie_info (cie, context, fs);
|
|
|
1267 if (insn == NULL)
|
|
|
1268 /* CIE contained unknown augmentation. */
|
|
|
1269 return _URC_FATAL_PHASE1_ERROR;
|
|
|
1270
|
|
|
1271 /* First decode all the insns in the CIE. */
|
|
|
1272 end = (const unsigned char *) next_fde ((const struct dwarf_fde *) cie);
|
|
|
1273 execute_cfa_program (insn, end, context, fs);
|
|
|
1274
|
|
|
1275 /* Locate augmentation for the fde. */
|
|
|
1276 aug = (const unsigned char *) fde + sizeof (*fde);
|
|
|
1277 aug += 2 * size_of_encoded_value (fs->fde_encoding);
|
|
|
1278 insn = NULL;
|
|
|
1279 if (fs->saw_z)
|
|
|
1280 {
|
|
|
1281 _uleb128_t i;
|
|
|
1282 aug = read_uleb128 (aug, &i);
|
|
|
1283 insn = aug + i;
|
|
|
1284 }
|
|
|
1285 if (fs->lsda_encoding != DW_EH_PE_omit)
|
|
|
1286 {
|
|
|
1287 _Unwind_Ptr lsda;
|
|
|
1288
|
|
|
1289 aug = read_encoded_value (context, fs->lsda_encoding, aug, &lsda);
|
|
|
1290 context->lsda = (void *) lsda;
|
|
|
1291 }
|
|
|
1292
|
|
|
1293 /* Then the insns in the FDE up to our target PC. */
|
|
|
1294 if (insn == NULL)
|
|
|
1295 insn = aug;
|
|
|
1296 end = (const unsigned char *) next_fde (fde);
|
|
|
1297 execute_cfa_program (insn, end, context, fs);
|
|
|
1298
|
|
|
1299 return _URC_NO_REASON;
|
|
|
1300 }
|
|
|
1301
|
|
|
1302 typedef struct frame_state
|
|
|
1303 {
|
|
|
1304 void *cfa;
|
|
|
1305 void *eh_ptr;
|
|
|
1306 long cfa_offset;
|
|
|
1307 long args_size;
|
|
|
1308 long reg_or_offset[PRE_GCC3_DWARF_FRAME_REGISTERS+1];
|
|
|
1309 unsigned short cfa_reg;
|
|
|
1310 unsigned short retaddr_column;
|
|
|
1311 char saved[PRE_GCC3_DWARF_FRAME_REGISTERS+1];
|
|
|
1312 } frame_state;
|
|
|
1313
|
|
|
1314 struct frame_state * __frame_state_for (void *, struct frame_state *);
|
|
|
1315
|
|
|
1316 /* Called from pre-G++ 3.0 __throw to find the registers to restore for
|
|
|
1317 a given PC_TARGET. The caller should allocate a local variable of
|
|
|
1318 `struct frame_state' and pass its address to STATE_IN. */
|
|
|
1319
|
|
|
1320 struct frame_state *
|
|
|
1321 __frame_state_for (void *pc_target, struct frame_state *state_in)
|
|
|
1322 {
|
|
|
1323 struct _Unwind_Context context;
|
|
|
1324 _Unwind_FrameState fs;
|
|
|
1325 int reg;
|
|
|
1326
|
|
|
1327 memset (&context, 0, sizeof (struct _Unwind_Context));
|
|
|
1328 if (!ASSUME_EXTENDED_UNWIND_CONTEXT)
|
|
|
1329 context.flags = EXTENDED_CONTEXT_BIT;
|
|
|
1330 context.ra = pc_target + 1;
|
|
|
1331
|
|
|
1332 if (uw_frame_state_for (&context, &fs) != _URC_NO_REASON)
|
|
|
1333 return 0;
|
|
|
1334
|
|
|
1335 /* We have no way to pass a location expression for the CFA to our
|
|
|
1336 caller. It wouldn't understand it anyway. */
|
|
|
1337 if (fs.regs.cfa_how == CFA_EXP)
|
|
|
1338 return 0;
|
|
|
1339
|
|
|
1340 for (reg = 0; reg < PRE_GCC3_DWARF_FRAME_REGISTERS + 1; reg++)
|
|
|
1341 {
|
|
|
1342 state_in->saved[reg] = fs.regs.reg[reg].how;
|
|
|
1343 switch (state_in->saved[reg])
|
|
|
1344 {
|
|
|
1345 case REG_SAVED_REG:
|
|
|
1346 state_in->reg_or_offset[reg] = fs.regs.reg[reg].loc.reg;
|
|
|
1347 break;
|
|
|
1348 case REG_SAVED_OFFSET:
|
|
|
1349 state_in->reg_or_offset[reg] = fs.regs.reg[reg].loc.offset;
|
|
|
1350 break;
|
|
|
1351 default:
|
|
|
1352 state_in->reg_or_offset[reg] = 0;
|
|
|
1353 break;
|
|
|
1354 }
|
|
|
1355 }
|
|
|
1356
|
|
|
1357 state_in->cfa_offset = fs.regs.cfa_offset;
|
|
|
1358 state_in->cfa_reg = fs.regs.cfa_reg;
|
|
|
1359 state_in->retaddr_column = fs.retaddr_column;
|
|
|
1360 state_in->args_size = context.args_size;
|
|
|
1361 state_in->eh_ptr = fs.eh_ptr;
|
|
|
1362
|
|
|
1363 return state_in;
|
|
|
1364 }
|
|
|
1365
|
|
|
1366 typedef union { _Unwind_Ptr ptr; _Unwind_Word word; } _Unwind_SpTmp;
|
|
|
1367
|
|
|
1368 static inline void
|
|
|
1369 _Unwind_SetSpColumn (struct _Unwind_Context *context, void *cfa,
|
|
|
1370 _Unwind_SpTmp *tmp_sp)
|
|
|
1371 {
|
|
|
1372 int size = dwarf_reg_size_table[__builtin_dwarf_sp_column ()];
|
|
|
1373
|
|
|
1374 if (size == sizeof(_Unwind_Ptr))
|
|
|
1375 tmp_sp->ptr = (_Unwind_Ptr) cfa;
|
|
|
1376 else
|
|
|
1377 {
|
|
|
1378 gcc_assert (size == sizeof(_Unwind_Word));
|
|
|
1379 tmp_sp->word = (_Unwind_Ptr) cfa;
|
|
|
1380 }
|
|
|
1381 _Unwind_SetGRPtr (context, __builtin_dwarf_sp_column (), tmp_sp);
|
|
|
1382 }
|
|
|
1383
|
|
|
1384 static void
|
|
|
1385 uw_update_context_1 (struct _Unwind_Context *context, _Unwind_FrameState *fs)
|
|
|
1386 {
|
|
|
1387 struct _Unwind_Context orig_context = *context;
|
|
|
1388 void *cfa;
|
|
|
1389 long i;
|
|
|
1390
|
|
|
1391 #ifdef __LIBGCC_EH_RETURN_STACKADJ_RTX__
|
|
|
1392 /* Special handling here: Many machines do not use a frame pointer,
|
|
|
1393 and track the CFA only through offsets from the stack pointer from
|
|
|
1394 one frame to the next. In this case, the stack pointer is never
|
|
|
1395 stored, so it has no saved address in the context. What we do
|
|
|
1396 have is the CFA from the previous stack frame.
|
|
|
1397
|
|
|
1398 In very special situations (such as unwind info for signal return),
|
|
|
1399 there may be location expressions that use the stack pointer as well.
|
|
|
1400
|
|
|
1401 Do this conditionally for one frame. This allows the unwind info
|
|
|
1402 for one frame to save a copy of the stack pointer from the previous
|
|
|
1403 frame, and be able to use much easier CFA mechanisms to do it.
|
|
|
1404 Always zap the saved stack pointer value for the next frame; carrying
|
|
|
1405 the value over from one frame to another doesn't make sense. */
|
|
|
1406
|
|
|
1407 _Unwind_SpTmp tmp_sp;
|
|
|
1408
|
|
|
1409 if (!_Unwind_GetGRPtr (&orig_context, __builtin_dwarf_sp_column ()))
|
|
|
1410 _Unwind_SetSpColumn (&orig_context, context->cfa, &tmp_sp);
|
|
|
1411 _Unwind_SetGRPtr (context, __builtin_dwarf_sp_column (), NULL);
|
|
|
1412 #endif
|
|
|
1413
|
|
|
1414 /* Compute this frame's CFA. */
|
|
|
1415 switch (fs->regs.cfa_how)
|
|
|
1416 {
|
|
|
1417 case CFA_REG_OFFSET:
|
|
|
1418 cfa = _Unwind_GetPtr (&orig_context, fs->regs.cfa_reg);
|
|
|
1419 cfa += fs->regs.cfa_offset;
|
|
|
1420 break;
|
|
|
1421
|
|
|
1422 case CFA_EXP:
|
|
|
1423 {
|
|
|
1424 const unsigned char *exp = fs->regs.cfa_exp;
|
|
|
1425 _uleb128_t len;
|
|
|
1426
|
|
|
1427 exp = read_uleb128 (exp, &len);
|
|
|
1428 cfa = (void *) (_Unwind_Ptr)
|
|
|
1429 execute_stack_op (exp, exp + len, &orig_context, 0);
|
|
|
1430 break;
|
|
|
1431 }
|
|
|
1432
|
|
|
1433 default:
|
|
|
1434 gcc_unreachable ();
|
|
|
1435 }
|
|
|
1436 context->cfa = cfa;
|
|
|
1437
|
|
|
1438 /* Compute the addresses of all registers saved in this frame. */
|
|
|
1439 for (i = 0; i < __LIBGCC_DWARF_FRAME_REGISTERS__ + 1; ++i)
|
|
|
1440 switch (fs->regs.reg[i].how)
|
|
|
1441 {
|
|
|
1442 case REG_UNSAVED:
|
|
|
1443 case REG_UNDEFINED:
|
|
|
1444 break;
|
|
|
1445
|
|
|
1446 case REG_SAVED_OFFSET:
|
|
|
1447 _Unwind_SetGRPtr (context, i,
|
|
|
1448 (void *) (cfa + fs->regs.reg[i].loc.offset));
|
|
|
1449 break;
|
|
|
1450
|
|
|
1451 case REG_SAVED_REG:
|
|
|
1452 if (_Unwind_GRByValue (&orig_context, fs->regs.reg[i].loc.reg))
|
|
|
1453 _Unwind_SetGRValue (context, i,
|
|
|
1454 _Unwind_GetGR (&orig_context,
|
|
|
1455 fs->regs.reg[i].loc.reg));
|
|
|
1456 else
|
|
|
1457 _Unwind_SetGRPtr (context, i,
|
|
|
1458 _Unwind_GetGRPtr (&orig_context,
|
|
|
1459 fs->regs.reg[i].loc.reg));
|
|
|
1460 break;
|
|
|
1461
|
|
|
1462 case REG_SAVED_EXP:
|
|
|
1463 {
|
|
|
1464 const unsigned char *exp = fs->regs.reg[i].loc.exp;
|
|
|
1465 _uleb128_t len;
|
|
|
1466 _Unwind_Ptr val;
|
|
|
1467
|
|
|
1468 exp = read_uleb128 (exp, &len);
|
|
|
1469 val = execute_stack_op (exp, exp + len, &orig_context,
|
|
|
1470 (_Unwind_Ptr) cfa);
|
|
|
1471 _Unwind_SetGRPtr (context, i, (void *) val);
|
|
|
1472 }
|
|
|
1473 break;
|
|
|
1474
|
|
|
1475 case REG_SAVED_VAL_OFFSET:
|
|
|
1476 _Unwind_SetGRValue (context, i,
|
|
|
1477 (_Unwind_Internal_Ptr)
|
|
|
1478 (cfa + fs->regs.reg[i].loc.offset));
|
|
|
1479 break;
|
|
|
1480
|
|
|
1481 case REG_SAVED_VAL_EXP:
|
|
|
1482 {
|
|
|
1483 const unsigned char *exp = fs->regs.reg[i].loc.exp;
|
|
|
1484 _uleb128_t len;
|
|
|
1485 _Unwind_Ptr val;
|
|
|
1486
|
|
|
1487 exp = read_uleb128 (exp, &len);
|
|
|
1488 val = execute_stack_op (exp, exp + len, &orig_context,
|
|
|
1489 (_Unwind_Ptr) cfa);
|
|
|
1490 _Unwind_SetGRValue (context, i, val);
|
|
|
1491 }
|
|
|
1492 break;
|
|
|
1493 }
|
|
|
1494
|
|
|
1495 _Unwind_SetSignalFrame (context, fs->signal_frame);
|
|
|
1496
|
|
|
1497 #ifdef MD_FROB_UPDATE_CONTEXT
|
|
|
1498 MD_FROB_UPDATE_CONTEXT (context, fs);
|
|
|
1499 #endif
|
|
|
1500 }
|
|
|
1501
|
|
|
1502 /* CONTEXT describes the unwind state for a frame, and FS describes the FDE
|
|
|
1503 of its caller. Update CONTEXT to refer to the caller as well. Note
|
|
|
1504 that the args_size and lsda members are not updated here, but later in
|
|
|
1505 uw_frame_state_for. */
|
|
|
1506
|
|
|
1507 static void
|
|
|
1508 uw_update_context (struct _Unwind_Context *context, _Unwind_FrameState *fs)
|
|
|
1509 {
|
|
|
1510 uw_update_context_1 (context, fs);
|
|
|
1511
|
|
|
1512 /* In general this unwinder doesn't make any distinction between
|
|
|
1513 undefined and same_value rule. Call-saved registers are assumed
|
|
|
1514 to have same_value rule by default and explicit undefined
|
|
|
1515 rule is handled like same_value. The only exception is
|
|
|
1516 DW_CFA_undefined on retaddr_column which is supposed to
|
|
|
1517 mark outermost frame in DWARF 3. */
|
|
|
1518 if (fs->regs.reg[DWARF_REG_TO_UNWIND_COLUMN (fs->retaddr_column)].how
|
|
|
1519 == REG_UNDEFINED)
|
|
|
1520 /* uw_frame_state_for uses context->ra == 0 check to find outermost
|
|
|
1521 stack frame. */
|
|
|
1522 context->ra = 0;
|
|
|
1523 else
|
|
|
1524 {
|
|
|
1525 /* Compute the return address now, since the return address column
|
|
|
1526 can change from frame to frame. */
|
|
|
1527 context->ra = __builtin_extract_return_addr
|
|
|
1528 (_Unwind_GetPtr (context, fs->retaddr_column));
|
|
|
1529 #ifdef MD_POST_EXTRACT_FRAME_ADDR
|
|
|
1530 context->ra = MD_POST_EXTRACT_FRAME_ADDR (context, fs, context->ra);
|
|
|
1531 #endif
|
|
|
1532 }
|
|
|
1533 }
|
|
|
1534
|
|
|
1535 static void
|
|
|
1536 uw_advance_context (struct _Unwind_Context *context, _Unwind_FrameState *fs)
|
|
|
1537 {
|
|
|
1538 uw_update_context (context, fs);
|
|
|
1539 }
|
|
|
1540
|
|
|
1541 /* Fill in CONTEXT for top-of-stack. The only valid registers at this
|
|
|
1542 level will be the return address and the CFA. */
|
|
|
1543
|
|
|
1544 #define uw_init_context(CONTEXT) \
|
|
|
1545 do \
|
|
|
1546 { \
|
|
|
1547 /* Do any necessary initialization to access arbitrary stack frames. \
|
|
|
1548 On the SPARC, this means flushing the register windows. */ \
|
|
|
1549 __builtin_unwind_init (); \
|
|
|
1550 uw_init_context_1 (CONTEXT, __builtin_dwarf_cfa (), \
|
|
|
1551 __builtin_return_address (0)); \
|
|
|
1552 } \
|
|
|
1553 while (0)
|
|
|
1554
|
|
|
1555 static inline void
|
|
|
1556 init_dwarf_reg_size_table (void)
|
|
|
1557 {
|
|
|
1558 __builtin_init_dwarf_reg_size_table (dwarf_reg_size_table);
|
|
|
1559 }
|
|
|
1560
|
|
|
1561 static void __attribute__((noinline))
|
|
|
1562 uw_init_context_1 (struct _Unwind_Context *context,
|
|
|
1563 void *outer_cfa, void *outer_ra)
|
|
|
1564 {
|
|
|
1565 void *ra = __builtin_extract_return_addr (__builtin_return_address (0));
|
|
|
1566 #ifdef MD_POST_EXTRACT_ROOT_ADDR
|
|
|
1567 ra = MD_POST_EXTRACT_ROOT_ADDR (ra);
|
|
|
1568 #endif
|
|
|
1569 _Unwind_FrameState fs;
|
|
|
1570 _Unwind_SpTmp sp_slot;
|
|
|
1571 _Unwind_Reason_Code code;
|
|
|
1572
|
|
|
1573 memset (context, 0, sizeof (struct _Unwind_Context));
|
|
|
1574 context->ra = ra;
|
|
|
1575 if (!ASSUME_EXTENDED_UNWIND_CONTEXT)
|
|
|
1576 context->flags = EXTENDED_CONTEXT_BIT;
|
|
|
1577
|
|
|
1578 code = uw_frame_state_for (context, &fs);
|
|
|
1579 gcc_assert (code == _URC_NO_REASON);
|
|
|
1580
|
|
|
1581 #if __GTHREADS
|
|
|
1582 {
|
|
|
1583 static __gthread_once_t once_regsizes = __GTHREAD_ONCE_INIT;
|
|
|
1584 if (__gthread_once (&once_regsizes, init_dwarf_reg_size_table) != 0
|
|
|
1585 && dwarf_reg_size_table[0] == 0)
|
|
|
1586 init_dwarf_reg_size_table ();
|
|
|
1587 }
|
|
|
1588 #else
|
|
|
1589 if (dwarf_reg_size_table[0] == 0)
|
|
|
1590 init_dwarf_reg_size_table ();
|
|
|
1591 #endif
|
|
|
1592
|
|
|
1593 /* Force the frame state to use the known cfa value. */
|
|
|
1594 _Unwind_SetSpColumn (context, outer_cfa, &sp_slot);
|
|
|
1595 fs.regs.cfa_how = CFA_REG_OFFSET;
|
|
|
1596 fs.regs.cfa_reg = __builtin_dwarf_sp_column ();
|
|
|
1597 fs.regs.cfa_offset = 0;
|
|
|
1598
|
|
|
1599 uw_update_context_1 (context, &fs);
|
|
|
1600
|
|
|
1601 /* If the return address column was saved in a register in the
|
|
|
1602 initialization context, then we can't see it in the given
|
|
|
1603 call frame data. So have the initialization context tell us. */
|
|
|
1604 context->ra = __builtin_extract_return_addr (outer_ra);
|
|
|
1605 #ifdef MD_POST_EXTRACT_ROOT_ADDR
|
|
|
1606 context->ra = MD_POST_EXTRACT_ROOT_ADDR (context->ra);
|
|
|
1607 #endif
|
|
|
1608 }
|
|
|
1609
|
|
|
1610 static void _Unwind_DebugHook (void *, void *)
|
|
|
1611 __attribute__ ((__noinline__, __used__, __noclone__));
|
|
|
1612
|
|
|
1613 /* This function is called during unwinding. It is intended as a hook
|
|
|
1614 for a debugger to intercept exceptions. CFA is the CFA of the
|
|
|
1615 target frame. HANDLER is the PC to which control will be
|
|
|
1616 transferred. */
|
|
|
1617 static void
|
|
|
1618 _Unwind_DebugHook (void *cfa __attribute__ ((__unused__)),
|
|
|
1619 void *handler __attribute__ ((__unused__)))
|
|
|
1620 {
|
|
|
1621 /* We only want to use stap probes starting with v3. Earlier
|
|
|
1622 versions added too much startup cost. */
|
|
|
1623 #if defined (HAVE_SYS_SDT_H) && defined (STAP_PROBE2) && _SDT_NOTE_TYPE >= 3
|
|
|
1624 STAP_PROBE2 (libgcc, unwind, cfa, handler);
|
|
|
1625 #else
|
|
|
1626 asm ("");
|
|
|
1627 #endif
|
|
|
1628 }
|
|
|
1629
|
|
|
1630 /* Frob exception handler's address kept in TARGET before installing into
|
|
|
1631 CURRENT context. */
|
|
|
1632
|
|
|
1633 static inline void *
|
|
|
1634 uw_frob_return_addr (struct _Unwind_Context *current
|
|
|
1635 __attribute__ ((__unused__)),
|
|
|
1636 struct _Unwind_Context *target)
|
|
|
1637 {
|
|
|
1638 void *ret_addr = __builtin_frob_return_addr (target->ra);
|
|
|
1639 #ifdef MD_POST_FROB_EH_HANDLER_ADDR
|
|
|
1640 ret_addr = MD_POST_FROB_EH_HANDLER_ADDR (current, target, ret_addr);
|
|
|
1641 #endif
|
|
|
1642 return ret_addr;
|
|
|
1643 }
|
|
|
1644
|
|
|
1645 /* Install TARGET into CURRENT so that we can return to it. This is a
|
|
|
1646 macro because __builtin_eh_return must be invoked in the context of
|
|
|
1647 our caller. */
|
|
|
1648
|
|
|
1649 #define uw_install_context(CURRENT, TARGET) \
|
|
|
1650 do \
|
|
|
1651 { \
|
|
|
1652 long offset = uw_install_context_1 ((CURRENT), (TARGET)); \
|
|
|
1653 void *handler = uw_frob_return_addr ((CURRENT), (TARGET)); \
|
|
|
1654 _Unwind_DebugHook ((TARGET)->cfa, handler); \
|
|
|
1655 __builtin_eh_return (offset, handler); \
|
|
|
1656 } \
|
|
|
1657 while (0)
|
|
|
1658
|
|
|
1659 static long
|
|
|
1660 uw_install_context_1 (struct _Unwind_Context *current,
|
|
|
1661 struct _Unwind_Context *target)
|
|
|
1662 {
|
|
|
1663 long i;
|
|
|
1664 _Unwind_SpTmp sp_slot;
|
|
|
1665
|
|
|
1666 /* If the target frame does not have a saved stack pointer,
|
|
|
1667 then set up the target's CFA. */
|
|
|
1668 if (!_Unwind_GetGRPtr (target, __builtin_dwarf_sp_column ()))
|
|
|
1669 _Unwind_SetSpColumn (target, target->cfa, &sp_slot);
|
|
|
1670
|
|
|
1671 for (i = 0; i < __LIBGCC_DWARF_FRAME_REGISTERS__; ++i)
|
|
|
1672 {
|
|
|
1673 void *c = (void *) (_Unwind_Internal_Ptr) current->reg[i];
|
|
|
1674 void *t = (void *) (_Unwind_Internal_Ptr)target->reg[i];
|
|
|
1675
|
|
|
1676 gcc_assert (current->by_value[i] == 0);
|
|
|
1677 if (target->by_value[i] && c)
|
|
|
1678 {
|
|
|
1679 _Unwind_Word w;
|
|
|
1680 _Unwind_Ptr p;
|
|
|
1681 if (dwarf_reg_size_table[i] == sizeof (_Unwind_Word))
|
|
|
1682 {
|
|
|
1683 w = (_Unwind_Internal_Ptr) t;
|
|
|
1684 memcpy (c, &w, sizeof (_Unwind_Word));
|
|
|
1685 }
|
|
|
1686 else
|
|
|
1687 {
|
|
|
1688 gcc_assert (dwarf_reg_size_table[i] == sizeof (_Unwind_Ptr));
|
|
|
1689 p = (_Unwind_Internal_Ptr) t;
|
|
|
1690 memcpy (c, &p, sizeof (_Unwind_Ptr));
|
|
|
1691 }
|
|
|
1692 }
|
|
|
1693 else if (t && c && t != c)
|
|
|
1694 memcpy (c, t, dwarf_reg_size_table[i]);
|
|
|
1695 }
|
|
|
1696
|
|
|
1697 /* If the current frame doesn't have a saved stack pointer, then we
|
|
|
1698 need to rely on EH_RETURN_STACKADJ_RTX to get our target stack
|
|
|
1699 pointer value reloaded. */
|
|
|
1700 if (!_Unwind_GetGRPtr (current, __builtin_dwarf_sp_column ()))
|
|
|
1701 {
|
|
|
1702 void *target_cfa;
|
|
|
1703
|
|
|
1704 target_cfa = _Unwind_GetPtr (target, __builtin_dwarf_sp_column ());
|
|
|
1705
|
|
|
1706 /* We adjust SP by the difference between CURRENT and TARGET's CFA. */
|
|
|
1707 if (__LIBGCC_STACK_GROWS_DOWNWARD__)
|
|
|
1708 return target_cfa - current->cfa + target->args_size;
|
|
|
1709 else
|
|
|
1710 return current->cfa - target_cfa - target->args_size;
|
|
|
1711 }
|
|
|
1712 return 0;
|
|
|
1713 }
|
|
|
1714
|
|
|
1715 static inline _Unwind_Ptr
|
|
|
1716 uw_identify_context (struct _Unwind_Context *context)
|
|
|
1717 {
|
|
|
1718 /* The CFA is not sufficient to disambiguate the context of a function
|
|
|
1719 interrupted by a signal before establishing its frame and the context
|
|
|
1720 of the signal itself. */
|
|
|
1721 if (__LIBGCC_STACK_GROWS_DOWNWARD__)
|
|
|
1722 return _Unwind_GetCFA (context) - _Unwind_IsSignalFrame (context);
|
|
|
1723 else
|
|
|
1724 return _Unwind_GetCFA (context) + _Unwind_IsSignalFrame (context);
|
|
|
1725 }
|
|
|
1726
|
|
|
1727
|
|
|
1728 #include "unwind.inc"
|
|
|
1729
|
|
|
1730 #if defined (USE_GAS_SYMVER) && defined (SHARED) && defined (USE_LIBUNWIND_EXCEPTIONS)
|
|
|
1731 alias (_Unwind_Backtrace);
|
|
|
1732 alias (_Unwind_DeleteException);
|
|
|
1733 alias (_Unwind_FindEnclosingFunction);
|
|
|
1734 alias (_Unwind_ForcedUnwind);
|
|
|
1735 alias (_Unwind_GetDataRelBase);
|
|
|
1736 alias (_Unwind_GetTextRelBase);
|
|
|
1737 alias (_Unwind_GetCFA);
|
|
|
1738 alias (_Unwind_GetGR);
|
|
|
1739 alias (_Unwind_GetIP);
|
|
|
1740 alias (_Unwind_GetLanguageSpecificData);
|
|
|
1741 alias (_Unwind_GetRegionStart);
|
|
|
1742 alias (_Unwind_RaiseException);
|
|
|
1743 alias (_Unwind_Resume);
|
|
|
1744 alias (_Unwind_Resume_or_Rethrow);
|
|
|
1745 alias (_Unwind_SetGR);
|
|
|
1746 alias (_Unwind_SetIP);
|
|
|
1747 #endif
|
|
|
1748
|
|
|
1749 #endif /* !USING_SJLJ_EXCEPTIONS */
|
