111
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1 /* DWARF2 exception handling and frame unwind runtime interface routines.
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131
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2 Copyright (C) 1997-2018 Free Software Foundation, Inc.
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111
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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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131
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219 /* Get the value of register REGNO 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 regno)
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223 {
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131
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224 int size, index;
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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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131
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232 index = DWARF_REG_TO_UNWIND_COLUMN (regno);
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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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131
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240 #ifdef DWARF_LAZY_REGISTER_VALUE
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241 {
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242 _Unwind_Word value;
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243 if (DWARF_LAZY_REGISTER_VALUE (regno, &value))
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244 return value;
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245 }
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246 #endif
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247
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111
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248 /* This will segfault if the register hasn't been saved. */
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249 if (size == sizeof(_Unwind_Ptr))
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250 return * (_Unwind_Ptr *) (_Unwind_Internal_Ptr) val;
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251 else
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252 {
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253 gcc_assert (size == sizeof(_Unwind_Word));
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254 return * (_Unwind_Word *) (_Unwind_Internal_Ptr) val;
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255 }
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256 }
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257
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258 static inline void *
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259 _Unwind_GetPtr (struct _Unwind_Context *context, int index)
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260 {
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261 return (void *)(_Unwind_Ptr) _Unwind_GetGR (context, index);
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262 }
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263
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264 /* Get the value of the CFA as saved in CONTEXT. */
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265
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266 _Unwind_Word
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267 _Unwind_GetCFA (struct _Unwind_Context *context)
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268 {
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269 return (_Unwind_Ptr) context->cfa;
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270 }
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271
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272 /* Overwrite the saved value for register INDEX in CONTEXT with VAL. */
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273
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274 inline void
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275 _Unwind_SetGR (struct _Unwind_Context *context, int index, _Unwind_Word val)
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276 {
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277 int size;
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278 void *ptr;
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279
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280 index = DWARF_REG_TO_UNWIND_COLUMN (index);
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281 gcc_assert (index < (int) sizeof(dwarf_reg_size_table));
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282 size = dwarf_reg_size_table[index];
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283
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284 if (_Unwind_IsExtendedContext (context) && context->by_value[index])
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285 {
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286 context->reg[index] = _Unwind_Get_Unwind_Context_Reg_Val (val);
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287 return;
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288 }
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289
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290 ptr = (void *) (_Unwind_Internal_Ptr) context->reg[index];
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291
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292 if (size == sizeof(_Unwind_Ptr))
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293 * (_Unwind_Ptr *) ptr = val;
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294 else
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295 {
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296 gcc_assert (size == sizeof(_Unwind_Word));
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297 * (_Unwind_Word *) ptr = val;
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298 }
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299 }
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300
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301 /* Get the pointer to a register INDEX as saved in CONTEXT. */
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302
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303 static inline void *
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304 _Unwind_GetGRPtr (struct _Unwind_Context *context, int index)
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305 {
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306 index = DWARF_REG_TO_UNWIND_COLUMN (index);
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307 if (_Unwind_IsExtendedContext (context) && context->by_value[index])
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308 return &context->reg[index];
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309 return (void *) (_Unwind_Internal_Ptr) context->reg[index];
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310 }
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311
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312 /* Set the pointer to a register INDEX as saved in CONTEXT. */
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313
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314 static inline void
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315 _Unwind_SetGRPtr (struct _Unwind_Context *context, int index, void *p)
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316 {
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317 index = DWARF_REG_TO_UNWIND_COLUMN (index);
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318 if (_Unwind_IsExtendedContext (context))
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319 context->by_value[index] = 0;
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320 context->reg[index] = (_Unwind_Context_Reg_Val) (_Unwind_Internal_Ptr) p;
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321 }
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322
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323 /* Overwrite the saved value for register INDEX in CONTEXT with VAL. */
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324
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325 static inline void
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326 _Unwind_SetGRValue (struct _Unwind_Context *context, int index,
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327 _Unwind_Word val)
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328 {
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329 index = DWARF_REG_TO_UNWIND_COLUMN (index);
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330 gcc_assert (index < (int) sizeof(dwarf_reg_size_table));
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331 /* Return column size may be smaller than _Unwind_Context_Reg_Val. */
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332 gcc_assert (dwarf_reg_size_table[index] <= sizeof (_Unwind_Context_Reg_Val));
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333
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334 context->by_value[index] = 1;
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335 context->reg[index] = _Unwind_Get_Unwind_Context_Reg_Val (val);
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336 }
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337
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338 /* Return nonzero if register INDEX is stored by value rather than
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339 by reference. */
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340
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341 static inline int
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342 _Unwind_GRByValue (struct _Unwind_Context *context, int index)
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343 {
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344 index = DWARF_REG_TO_UNWIND_COLUMN (index);
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345 return context->by_value[index];
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346 }
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347
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348 /* Retrieve the return address for CONTEXT. */
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349
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350 inline _Unwind_Ptr
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351 _Unwind_GetIP (struct _Unwind_Context *context)
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352 {
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353 return (_Unwind_Ptr) context->ra;
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354 }
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355
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356 /* Retrieve the return address and flag whether that IP is before
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357 or after first not yet fully executed instruction. */
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358
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359 inline _Unwind_Ptr
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360 _Unwind_GetIPInfo (struct _Unwind_Context *context, int *ip_before_insn)
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361 {
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362 *ip_before_insn = _Unwind_IsSignalFrame (context);
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363 return (_Unwind_Ptr) context->ra;
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364 }
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365
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366 /* Overwrite the return address for CONTEXT with VAL. */
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367
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368 inline void
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369 _Unwind_SetIP (struct _Unwind_Context *context, _Unwind_Ptr val)
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370 {
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371 context->ra = (void *) val;
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372 }
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373
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374 void *
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375 _Unwind_GetLanguageSpecificData (struct _Unwind_Context *context)
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376 {
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377 return context->lsda;
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378 }
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379
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380 _Unwind_Ptr
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381 _Unwind_GetRegionStart (struct _Unwind_Context *context)
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382 {
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383 return (_Unwind_Ptr) context->bases.func;
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384 }
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385
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386 void *
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387 _Unwind_FindEnclosingFunction (void *pc)
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388 {
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389 struct dwarf_eh_bases bases;
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390 const struct dwarf_fde *fde = _Unwind_Find_FDE (pc-1, &bases);
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391 if (fde)
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392 return bases.func;
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393 else
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394 return NULL;
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395 }
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396
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397 #ifndef __ia64__
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398 _Unwind_Ptr
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399 _Unwind_GetDataRelBase (struct _Unwind_Context *context)
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|
400 {
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401 return (_Unwind_Ptr) context->bases.dbase;
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402 }
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403
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404 _Unwind_Ptr
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405 _Unwind_GetTextRelBase (struct _Unwind_Context *context)
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406 {
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407 return (_Unwind_Ptr) context->bases.tbase;
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408 }
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409 #endif
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410
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411 #include "md-unwind-support.h"
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412
|
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413 /* Extract any interesting information from the CIE for the translation
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414 unit F belongs to. Return a pointer to the byte after the augmentation,
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415 or NULL if we encountered an undecipherable augmentation. */
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416
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417 static const unsigned char *
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418 extract_cie_info (const struct dwarf_cie *cie, struct _Unwind_Context *context,
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419 _Unwind_FrameState *fs)
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420 {
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421 const unsigned char *aug = cie->augmentation;
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422 const unsigned char *p = aug + strlen ((const char *)aug) + 1;
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423 const unsigned char *ret = NULL;
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424 _uleb128_t utmp;
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425 _sleb128_t stmp;
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426
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427 /* g++ v2 "eh" has pointer immediately following augmentation string,
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428 so it must be handled first. */
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429 if (aug[0] == 'e' && aug[1] == 'h')
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430 {
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431 fs->eh_ptr = read_pointer (p);
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432 p += sizeof (void *);
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433 aug += 2;
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|
434 }
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435
|
|
436 /* After the augmentation resp. pointer for "eh" augmentation
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437 follows for CIE version >= 4 address size byte and
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|
438 segment size byte. */
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|
439 if (__builtin_expect (cie->version >= 4, 0))
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440 {
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441 if (p[0] != sizeof (void *) || p[1] != 0)
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442 return NULL;
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443 p += 2;
|
|
444 }
|
|
445 /* Immediately following this are the code and
|
|
446 data alignment and return address column. */
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447 p = read_uleb128 (p, &utmp);
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448 fs->code_align = (_Unwind_Word)utmp;
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449 p = read_sleb128 (p, &stmp);
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450 fs->data_align = (_Unwind_Sword)stmp;
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|
451 if (cie->version == 1)
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452 fs->retaddr_column = *p++;
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453 else
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454 {
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455 p = read_uleb128 (p, &utmp);
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456 fs->retaddr_column = (_Unwind_Word)utmp;
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|
457 }
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458 fs->lsda_encoding = DW_EH_PE_omit;
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459
|
|
460 /* If the augmentation starts with 'z', then a uleb128 immediately
|
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461 follows containing the length of the augmentation field following
|
|
462 the size. */
|
|
463 if (*aug == 'z')
|
|
464 {
|
|
465 p = read_uleb128 (p, &utmp);
|
|
466 ret = p + utmp;
|
|
467
|
|
468 fs->saw_z = 1;
|
|
469 ++aug;
|
|
470 }
|
|
471
|
|
472 /* Iterate over recognized augmentation subsequences. */
|
|
473 while (*aug != '\0')
|
|
474 {
|
|
475 /* "L" indicates a byte showing how the LSDA pointer is encoded. */
|
|
476 if (aug[0] == 'L')
|
|
477 {
|
|
478 fs->lsda_encoding = *p++;
|
|
479 aug += 1;
|
|
480 }
|
|
481
|
|
482 /* "R" indicates a byte indicating how FDE addresses are encoded. */
|
|
483 else if (aug[0] == 'R')
|
|
484 {
|
|
485 fs->fde_encoding = *p++;
|
|
486 aug += 1;
|
|
487 }
|
|
488
|
|
489 /* "P" indicates a personality routine in the CIE augmentation. */
|
|
490 else if (aug[0] == 'P')
|
|
491 {
|
|
492 _Unwind_Ptr personality;
|
|
493
|
|
494 p = read_encoded_value (context, *p, p + 1, &personality);
|
|
495 fs->personality = (_Unwind_Personality_Fn) personality;
|
|
496 aug += 1;
|
|
497 }
|
|
498
|
|
499 /* "S" indicates a signal frame. */
|
|
500 else if (aug[0] == 'S')
|
|
501 {
|
|
502 fs->signal_frame = 1;
|
|
503 aug += 1;
|
|
504 }
|
|
505
|
|
506 /* Otherwise we have an unknown augmentation string.
|
|
507 Bail unless we saw a 'z' prefix. */
|
|
508 else
|
|
509 return ret;
|
|
510 }
|
|
511
|
|
512 return ret ? ret : p;
|
|
513 }
|
|
514
|
|
515
|
|
516 /* Decode a DW_OP stack program. Return the top of stack. Push INITIAL
|
|
517 onto the stack to start. */
|
|
518
|
|
519 static _Unwind_Word
|
|
520 execute_stack_op (const unsigned char *op_ptr, const unsigned char *op_end,
|
|
521 struct _Unwind_Context *context, _Unwind_Word initial)
|
|
522 {
|
|
523 _Unwind_Word stack[64]; /* ??? Assume this is enough. */
|
|
524 int stack_elt;
|
|
525
|
|
526 stack[0] = initial;
|
|
527 stack_elt = 1;
|
|
528
|
|
529 while (op_ptr < op_end)
|
|
530 {
|
|
531 enum dwarf_location_atom op = *op_ptr++;
|
|
532 _Unwind_Word result;
|
|
533 _uleb128_t reg, utmp;
|
|
534 _sleb128_t offset, stmp;
|
|
535
|
|
536 switch (op)
|
|
537 {
|
|
538 case DW_OP_lit0:
|
|
539 case DW_OP_lit1:
|
|
540 case DW_OP_lit2:
|
|
541 case DW_OP_lit3:
|
|
542 case DW_OP_lit4:
|
|
543 case DW_OP_lit5:
|
|
544 case DW_OP_lit6:
|
|
545 case DW_OP_lit7:
|
|
546 case DW_OP_lit8:
|
|
547 case DW_OP_lit9:
|
|
548 case DW_OP_lit10:
|
|
549 case DW_OP_lit11:
|
|
550 case DW_OP_lit12:
|
|
551 case DW_OP_lit13:
|
|
552 case DW_OP_lit14:
|
|
553 case DW_OP_lit15:
|
|
554 case DW_OP_lit16:
|
|
555 case DW_OP_lit17:
|
|
556 case DW_OP_lit18:
|
|
557 case DW_OP_lit19:
|
|
558 case DW_OP_lit20:
|
|
559 case DW_OP_lit21:
|
|
560 case DW_OP_lit22:
|
|
561 case DW_OP_lit23:
|
|
562 case DW_OP_lit24:
|
|
563 case DW_OP_lit25:
|
|
564 case DW_OP_lit26:
|
|
565 case DW_OP_lit27:
|
|
566 case DW_OP_lit28:
|
|
567 case DW_OP_lit29:
|
|
568 case DW_OP_lit30:
|
|
569 case DW_OP_lit31:
|
|
570 result = op - DW_OP_lit0;
|
|
571 break;
|
|
572
|
|
573 case DW_OP_addr:
|
|
574 result = (_Unwind_Word) (_Unwind_Ptr) read_pointer (op_ptr);
|
|
575 op_ptr += sizeof (void *);
|
|
576 break;
|
|
577
|
|
578 case DW_OP_GNU_encoded_addr:
|
|
579 {
|
|
580 _Unwind_Ptr presult;
|
|
581 op_ptr = read_encoded_value (context, *op_ptr, op_ptr+1, &presult);
|
|
582 result = presult;
|
|
583 }
|
|
584 break;
|
|
585
|
|
586 case DW_OP_const1u:
|
|
587 result = read_1u (op_ptr);
|
|
588 op_ptr += 1;
|
|
589 break;
|
|
590 case DW_OP_const1s:
|
|
591 result = read_1s (op_ptr);
|
|
592 op_ptr += 1;
|
|
593 break;
|
|
594 case DW_OP_const2u:
|
|
595 result = read_2u (op_ptr);
|
|
596 op_ptr += 2;
|
|
597 break;
|
|
598 case DW_OP_const2s:
|
|
599 result = read_2s (op_ptr);
|
|
600 op_ptr += 2;
|
|
601 break;
|
|
602 case DW_OP_const4u:
|
|
603 result = read_4u (op_ptr);
|
|
604 op_ptr += 4;
|
|
605 break;
|
|
606 case DW_OP_const4s:
|
|
607 result = read_4s (op_ptr);
|
|
608 op_ptr += 4;
|
|
609 break;
|
|
610 case DW_OP_const8u:
|
|
611 result = read_8u (op_ptr);
|
|
612 op_ptr += 8;
|
|
613 break;
|
|
614 case DW_OP_const8s:
|
|
615 result = read_8s (op_ptr);
|
|
616 op_ptr += 8;
|
|
617 break;
|
|
618 case DW_OP_constu:
|
|
619 op_ptr = read_uleb128 (op_ptr, &utmp);
|
|
620 result = (_Unwind_Word)utmp;
|
|
621 break;
|
|
622 case DW_OP_consts:
|
|
623 op_ptr = read_sleb128 (op_ptr, &stmp);
|
|
624 result = (_Unwind_Sword)stmp;
|
|
625 break;
|
|
626
|
|
627 case DW_OP_reg0:
|
|
628 case DW_OP_reg1:
|
|
629 case DW_OP_reg2:
|
|
630 case DW_OP_reg3:
|
|
631 case DW_OP_reg4:
|
|
632 case DW_OP_reg5:
|
|
633 case DW_OP_reg6:
|
|
634 case DW_OP_reg7:
|
|
635 case DW_OP_reg8:
|
|
636 case DW_OP_reg9:
|
|
637 case DW_OP_reg10:
|
|
638 case DW_OP_reg11:
|
|
639 case DW_OP_reg12:
|
|
640 case DW_OP_reg13:
|
|
641 case DW_OP_reg14:
|
|
642 case DW_OP_reg15:
|
|
643 case DW_OP_reg16:
|
|
644 case DW_OP_reg17:
|
|
645 case DW_OP_reg18:
|
|
646 case DW_OP_reg19:
|
|
647 case DW_OP_reg20:
|
|
648 case DW_OP_reg21:
|
|
649 case DW_OP_reg22:
|
|
650 case DW_OP_reg23:
|
|
651 case DW_OP_reg24:
|
|
652 case DW_OP_reg25:
|
|
653 case DW_OP_reg26:
|
|
654 case DW_OP_reg27:
|
|
655 case DW_OP_reg28:
|
|
656 case DW_OP_reg29:
|
|
657 case DW_OP_reg30:
|
|
658 case DW_OP_reg31:
|
|
659 result = _Unwind_GetGR (context, op - DW_OP_reg0);
|
|
660 break;
|
|
661 case DW_OP_regx:
|
|
662 op_ptr = read_uleb128 (op_ptr, ®);
|
|
663 result = _Unwind_GetGR (context, reg);
|
|
664 break;
|
|
665
|
|
666 case DW_OP_breg0:
|
|
667 case DW_OP_breg1:
|
|
668 case DW_OP_breg2:
|
|
669 case DW_OP_breg3:
|
|
670 case DW_OP_breg4:
|
|
671 case DW_OP_breg5:
|
|
672 case DW_OP_breg6:
|
|
673 case DW_OP_breg7:
|
|
674 case DW_OP_breg8:
|
|
675 case DW_OP_breg9:
|
|
676 case DW_OP_breg10:
|
|
677 case DW_OP_breg11:
|
|
678 case DW_OP_breg12:
|
|
679 case DW_OP_breg13:
|
|
680 case DW_OP_breg14:
|
|
681 case DW_OP_breg15:
|
|
682 case DW_OP_breg16:
|
|
683 case DW_OP_breg17:
|
|
684 case DW_OP_breg18:
|
|
685 case DW_OP_breg19:
|
|
686 case DW_OP_breg20:
|
|
687 case DW_OP_breg21:
|
|
688 case DW_OP_breg22:
|
|
689 case DW_OP_breg23:
|
|
690 case DW_OP_breg24:
|
|
691 case DW_OP_breg25:
|
|
692 case DW_OP_breg26:
|
|
693 case DW_OP_breg27:
|
|
694 case DW_OP_breg28:
|
|
695 case DW_OP_breg29:
|
|
696 case DW_OP_breg30:
|
|
697 case DW_OP_breg31:
|
|
698 op_ptr = read_sleb128 (op_ptr, &offset);
|
|
699 result = _Unwind_GetGR (context, op - DW_OP_breg0) + offset;
|
|
700 break;
|
|
701 case DW_OP_bregx:
|
|
702 op_ptr = read_uleb128 (op_ptr, ®);
|
|
703 op_ptr = read_sleb128 (op_ptr, &offset);
|
|
704 result = _Unwind_GetGR (context, reg) + (_Unwind_Word)offset;
|
|
705 break;
|
|
706
|
|
707 case DW_OP_dup:
|
|
708 gcc_assert (stack_elt);
|
|
709 result = stack[stack_elt - 1];
|
|
710 break;
|
|
711
|
|
712 case DW_OP_drop:
|
|
713 gcc_assert (stack_elt);
|
|
714 stack_elt -= 1;
|
|
715 goto no_push;
|
|
716
|
|
717 case DW_OP_pick:
|
|
718 offset = *op_ptr++;
|
|
719 gcc_assert (offset < stack_elt - 1);
|
|
720 result = stack[stack_elt - 1 - offset];
|
|
721 break;
|
|
722
|
|
723 case DW_OP_over:
|
|
724 gcc_assert (stack_elt >= 2);
|
|
725 result = stack[stack_elt - 2];
|
|
726 break;
|
|
727
|
|
728 case DW_OP_swap:
|
|
729 {
|
|
730 _Unwind_Word t;
|
|
731 gcc_assert (stack_elt >= 2);
|
|
732 t = stack[stack_elt - 1];
|
|
733 stack[stack_elt - 1] = stack[stack_elt - 2];
|
|
734 stack[stack_elt - 2] = t;
|
|
735 goto no_push;
|
|
736 }
|
|
737
|
|
738 case DW_OP_rot:
|
|
739 {
|
|
740 _Unwind_Word t1, t2, t3;
|
|
741
|
|
742 gcc_assert (stack_elt >= 3);
|
|
743 t1 = stack[stack_elt - 1];
|
|
744 t2 = stack[stack_elt - 2];
|
|
745 t3 = stack[stack_elt - 3];
|
|
746 stack[stack_elt - 1] = t2;
|
|
747 stack[stack_elt - 2] = t3;
|
|
748 stack[stack_elt - 3] = t1;
|
|
749 goto no_push;
|
|
750 }
|
|
751
|
|
752 case DW_OP_deref:
|
|
753 case DW_OP_deref_size:
|
|
754 case DW_OP_abs:
|
|
755 case DW_OP_neg:
|
|
756 case DW_OP_not:
|
|
757 case DW_OP_plus_uconst:
|
|
758 /* Unary operations. */
|
|
759 gcc_assert (stack_elt);
|
|
760 stack_elt -= 1;
|
|
761
|
|
762 result = stack[stack_elt];
|
|
763
|
|
764 switch (op)
|
|
765 {
|
|
766 case DW_OP_deref:
|
|
767 {
|
|
768 void *ptr = (void *) (_Unwind_Ptr) result;
|
|
769 result = (_Unwind_Ptr) read_pointer (ptr);
|
|
770 }
|
|
771 break;
|
|
772
|
|
773 case DW_OP_deref_size:
|
|
774 {
|
|
775 void *ptr = (void *) (_Unwind_Ptr) result;
|
|
776 switch (*op_ptr++)
|
|
777 {
|
|
778 case 1:
|
|
779 result = read_1u (ptr);
|
|
780 break;
|
|
781 case 2:
|
|
782 result = read_2u (ptr);
|
|
783 break;
|
|
784 case 4:
|
|
785 result = read_4u (ptr);
|
|
786 break;
|
|
787 case 8:
|
|
788 result = read_8u (ptr);
|
|
789 break;
|
|
790 default:
|
|
791 gcc_unreachable ();
|
|
792 }
|
|
793 }
|
|
794 break;
|
|
795
|
|
796 case DW_OP_abs:
|
|
797 if ((_Unwind_Sword) result < 0)
|
|
798 result = -result;
|
|
799 break;
|
|
800 case DW_OP_neg:
|
|
801 result = -result;
|
|
802 break;
|
|
803 case DW_OP_not:
|
|
804 result = ~result;
|
|
805 break;
|
|
806 case DW_OP_plus_uconst:
|
|
807 op_ptr = read_uleb128 (op_ptr, &utmp);
|
|
808 result += (_Unwind_Word)utmp;
|
|
809 break;
|
|
810
|
|
811 default:
|
|
812 gcc_unreachable ();
|
|
813 }
|
|
814 break;
|
|
815
|
|
816 case DW_OP_and:
|
|
817 case DW_OP_div:
|
|
818 case DW_OP_minus:
|
|
819 case DW_OP_mod:
|
|
820 case DW_OP_mul:
|
|
821 case DW_OP_or:
|
|
822 case DW_OP_plus:
|
|
823 case DW_OP_shl:
|
|
824 case DW_OP_shr:
|
|
825 case DW_OP_shra:
|
|
826 case DW_OP_xor:
|
|
827 case DW_OP_le:
|
|
828 case DW_OP_ge:
|
|
829 case DW_OP_eq:
|
|
830 case DW_OP_lt:
|
|
831 case DW_OP_gt:
|
|
832 case DW_OP_ne:
|
|
833 {
|
|
834 /* Binary operations. */
|
|
835 _Unwind_Word first, second;
|
|
836 gcc_assert (stack_elt >= 2);
|
|
837 stack_elt -= 2;
|
|
838
|
|
839 second = stack[stack_elt];
|
|
840 first = stack[stack_elt + 1];
|
|
841
|
|
842 switch (op)
|
|
843 {
|
|
844 case DW_OP_and:
|
|
845 result = second & first;
|
|
846 break;
|
|
847 case DW_OP_div:
|
|
848 result = (_Unwind_Sword) second / (_Unwind_Sword) first;
|
|
849 break;
|
|
850 case DW_OP_minus:
|
|
851 result = second - first;
|
|
852 break;
|
|
853 case DW_OP_mod:
|
|
854 result = second % first;
|
|
855 break;
|
|
856 case DW_OP_mul:
|
|
857 result = second * first;
|
|
858 break;
|
|
859 case DW_OP_or:
|
|
860 result = second | first;
|
|
861 break;
|
|
862 case DW_OP_plus:
|
|
863 result = second + first;
|
|
864 break;
|
|
865 case DW_OP_shl:
|
|
866 result = second << first;
|
|
867 break;
|
|
868 case DW_OP_shr:
|
|
869 result = second >> first;
|
|
870 break;
|
|
871 case DW_OP_shra:
|
|
872 result = (_Unwind_Sword) second >> first;
|
|
873 break;
|
|
874 case DW_OP_xor:
|
|
875 result = second ^ first;
|
|
876 break;
|
|
877 case DW_OP_le:
|
|
878 result = (_Unwind_Sword) second <= (_Unwind_Sword) first;
|
|
879 break;
|
|
880 case DW_OP_ge:
|
|
881 result = (_Unwind_Sword) second >= (_Unwind_Sword) first;
|
|
882 break;
|
|
883 case DW_OP_eq:
|
|
884 result = (_Unwind_Sword) second == (_Unwind_Sword) first;
|
|
885 break;
|
|
886 case DW_OP_lt:
|
|
887 result = (_Unwind_Sword) second < (_Unwind_Sword) first;
|
|
888 break;
|
|
889 case DW_OP_gt:
|
|
890 result = (_Unwind_Sword) second > (_Unwind_Sword) first;
|
|
891 break;
|
|
892 case DW_OP_ne:
|
|
893 result = (_Unwind_Sword) second != (_Unwind_Sword) first;
|
|
894 break;
|
|
895
|
|
896 default:
|
|
897 gcc_unreachable ();
|
|
898 }
|
|
899 }
|
|
900 break;
|
|
901
|
|
902 case DW_OP_skip:
|
|
903 offset = read_2s (op_ptr);
|
|
904 op_ptr += 2;
|
|
905 op_ptr += offset;
|
|
906 goto no_push;
|
|
907
|
|
908 case DW_OP_bra:
|
|
909 gcc_assert (stack_elt);
|
|
910 stack_elt -= 1;
|
|
911
|
|
912 offset = read_2s (op_ptr);
|
|
913 op_ptr += 2;
|
|
914 if (stack[stack_elt] != 0)
|
|
915 op_ptr += offset;
|
|
916 goto no_push;
|
|
917
|
|
918 case DW_OP_nop:
|
|
919 goto no_push;
|
|
920
|
|
921 default:
|
|
922 gcc_unreachable ();
|
|
923 }
|
|
924
|
|
925 /* Most things push a result value. */
|
|
926 gcc_assert ((size_t) stack_elt < sizeof(stack)/sizeof(*stack));
|
|
927 stack[stack_elt++] = result;
|
|
928 no_push:;
|
|
929 }
|
|
930
|
|
931 /* We were executing this program to get a value. It should be
|
|
932 at top of stack. */
|
|
933 gcc_assert (stack_elt);
|
|
934 stack_elt -= 1;
|
|
935 return stack[stack_elt];
|
|
936 }
|
|
937
|
|
938
|
|
939 /* Decode DWARF 2 call frame information. Takes pointers the
|
|
940 instruction sequence to decode, current register information and
|
|
941 CIE info, and the PC range to evaluate. */
|
|
942
|
|
943 static void
|
|
944 execute_cfa_program (const unsigned char *insn_ptr,
|
|
945 const unsigned char *insn_end,
|
|
946 struct _Unwind_Context *context,
|
|
947 _Unwind_FrameState *fs)
|
|
948 {
|
|
949 struct frame_state_reg_info *unused_rs = NULL;
|
|
950
|
|
951 /* Don't allow remember/restore between CIE and FDE programs. */
|
|
952 fs->regs.prev = NULL;
|
|
953
|
|
954 /* The comparison with the return address uses < rather than <= because
|
|
955 we are only interested in the effects of code before the call; for a
|
|
956 noreturn function, the return address may point to unrelated code with
|
|
957 a different stack configuration that we are not interested in. We
|
|
958 assume that the call itself is unwind info-neutral; if not, or if
|
|
959 there are delay instructions that adjust the stack, these must be
|
|
960 reflected at the point immediately before the call insn.
|
|
961 In signal frames, return address is after last completed instruction,
|
|
962 so we add 1 to return address to make the comparison <=. */
|
|
963 while (insn_ptr < insn_end
|
|
964 && fs->pc < context->ra + _Unwind_IsSignalFrame (context))
|
|
965 {
|
|
966 unsigned char insn = *insn_ptr++;
|
|
967 _uleb128_t reg, utmp;
|
|
968 _sleb128_t offset, stmp;
|
|
969
|
|
970 if ((insn & 0xc0) == DW_CFA_advance_loc)
|
|
971 fs->pc += (insn & 0x3f) * fs->code_align;
|
|
972 else if ((insn & 0xc0) == DW_CFA_offset)
|
|
973 {
|
|
974 reg = insn & 0x3f;
|
|
975 insn_ptr = read_uleb128 (insn_ptr, &utmp);
|
|
976 offset = (_Unwind_Sword) utmp * fs->data_align;
|
|
977 reg = DWARF_REG_TO_UNWIND_COLUMN (reg);
|
|
978 if (UNWIND_COLUMN_IN_RANGE (reg))
|
|
979 {
|
|
980 fs->regs.reg[reg].how = REG_SAVED_OFFSET;
|
|
981 fs->regs.reg[reg].loc.offset = offset;
|
|
982 }
|
|
983 }
|
|
984 else if ((insn & 0xc0) == DW_CFA_restore)
|
|
985 {
|
|
986 reg = insn & 0x3f;
|
|
987 reg = DWARF_REG_TO_UNWIND_COLUMN (reg);
|
|
988 if (UNWIND_COLUMN_IN_RANGE (reg))
|
|
989 fs->regs.reg[reg].how = REG_UNSAVED;
|
|
990 }
|
|
991 else switch (insn)
|
|
992 {
|
|
993 case DW_CFA_set_loc:
|
|
994 {
|
|
995 _Unwind_Ptr pc;
|
|
996
|
|
997 insn_ptr = read_encoded_value (context, fs->fde_encoding,
|
|
998 insn_ptr, &pc);
|
|
999 fs->pc = (void *) pc;
|
|
1000 }
|
|
1001 break;
|
|
1002
|
|
1003 case DW_CFA_advance_loc1:
|
|
1004 fs->pc += read_1u (insn_ptr) * fs->code_align;
|
|
1005 insn_ptr += 1;
|
|
1006 break;
|
|
1007 case DW_CFA_advance_loc2:
|
|
1008 fs->pc += read_2u (insn_ptr) * fs->code_align;
|
|
1009 insn_ptr += 2;
|
|
1010 break;
|
|
1011 case DW_CFA_advance_loc4:
|
|
1012 fs->pc += read_4u (insn_ptr) * fs->code_align;
|
|
1013 insn_ptr += 4;
|
|
1014 break;
|
|
1015
|
|
1016 case DW_CFA_offset_extended:
|
|
1017 insn_ptr = read_uleb128 (insn_ptr, ®);
|
|
1018 insn_ptr = read_uleb128 (insn_ptr, &utmp);
|
|
1019 offset = (_Unwind_Sword) utmp * fs->data_align;
|
|
1020 reg = DWARF_REG_TO_UNWIND_COLUMN (reg);
|
|
1021 if (UNWIND_COLUMN_IN_RANGE (reg))
|
|
1022 {
|
|
1023 fs->regs.reg[reg].how = REG_SAVED_OFFSET;
|
|
1024 fs->regs.reg[reg].loc.offset = offset;
|
|
1025 }
|
|
1026 break;
|
|
1027
|
|
1028 case DW_CFA_restore_extended:
|
|
1029 insn_ptr = read_uleb128 (insn_ptr, ®);
|
|
1030 /* FIXME, this is wrong; the CIE might have said that the
|
|
1031 register was saved somewhere. */
|
|
1032 reg = DWARF_REG_TO_UNWIND_COLUMN (reg);
|
|
1033 if (UNWIND_COLUMN_IN_RANGE (reg))
|
|
1034 fs->regs.reg[reg].how = REG_UNSAVED;
|
|
1035 break;
|
|
1036
|
|
1037 case DW_CFA_same_value:
|
|
1038 insn_ptr = read_uleb128 (insn_ptr, ®);
|
|
1039 reg = DWARF_REG_TO_UNWIND_COLUMN (reg);
|
|
1040 if (UNWIND_COLUMN_IN_RANGE (reg))
|
|
1041 fs->regs.reg[reg].how = REG_UNSAVED;
|
|
1042 break;
|
|
1043
|
|
1044 case DW_CFA_undefined:
|
|
1045 insn_ptr = read_uleb128 (insn_ptr, ®);
|
|
1046 reg = DWARF_REG_TO_UNWIND_COLUMN (reg);
|
|
1047 if (UNWIND_COLUMN_IN_RANGE (reg))
|
|
1048 fs->regs.reg[reg].how = REG_UNDEFINED;
|
|
1049 break;
|
|
1050
|
|
1051 case DW_CFA_nop:
|
|
1052 break;
|
|
1053
|
|
1054 case DW_CFA_register:
|
|
1055 {
|
|
1056 _uleb128_t reg2;
|
|
1057 insn_ptr = read_uleb128 (insn_ptr, ®);
|
|
1058 insn_ptr = read_uleb128 (insn_ptr, ®2);
|
|
1059 reg = DWARF_REG_TO_UNWIND_COLUMN (reg);
|
|
1060 if (UNWIND_COLUMN_IN_RANGE (reg))
|
|
1061 {
|
|
1062 fs->regs.reg[reg].how = REG_SAVED_REG;
|
|
1063 fs->regs.reg[reg].loc.reg = (_Unwind_Word)reg2;
|
|
1064 }
|
|
1065 }
|
|
1066 break;
|
|
1067
|
|
1068 case DW_CFA_remember_state:
|
|
1069 {
|
|
1070 struct frame_state_reg_info *new_rs;
|
|
1071 if (unused_rs)
|
|
1072 {
|
|
1073 new_rs = unused_rs;
|
|
1074 unused_rs = unused_rs->prev;
|
|
1075 }
|
|
1076 else
|
|
1077 new_rs = alloca (sizeof (struct frame_state_reg_info));
|
|
1078
|
|
1079 *new_rs = fs->regs;
|
|
1080 fs->regs.prev = new_rs;
|
|
1081 }
|
|
1082 break;
|
|
1083
|
|
1084 case DW_CFA_restore_state:
|
|
1085 {
|
|
1086 struct frame_state_reg_info *old_rs = fs->regs.prev;
|
|
1087 fs->regs = *old_rs;
|
|
1088 old_rs->prev = unused_rs;
|
|
1089 unused_rs = old_rs;
|
|
1090 }
|
|
1091 break;
|
|
1092
|
|
1093 case DW_CFA_def_cfa:
|
|
1094 insn_ptr = read_uleb128 (insn_ptr, &utmp);
|
|
1095 fs->regs.cfa_reg = (_Unwind_Word)utmp;
|
|
1096 insn_ptr = read_uleb128 (insn_ptr, &utmp);
|
|
1097 fs->regs.cfa_offset = (_Unwind_Word)utmp;
|
|
1098 fs->regs.cfa_how = CFA_REG_OFFSET;
|
|
1099 break;
|
|
1100
|
|
1101 case DW_CFA_def_cfa_register:
|
|
1102 insn_ptr = read_uleb128 (insn_ptr, &utmp);
|
|
1103 fs->regs.cfa_reg = (_Unwind_Word)utmp;
|
|
1104 fs->regs.cfa_how = CFA_REG_OFFSET;
|
|
1105 break;
|
|
1106
|
|
1107 case DW_CFA_def_cfa_offset:
|
|
1108 insn_ptr = read_uleb128 (insn_ptr, &utmp);
|
|
1109 fs->regs.cfa_offset = utmp;
|
|
1110 /* cfa_how deliberately not set. */
|
|
1111 break;
|
|
1112
|
|
1113 case DW_CFA_def_cfa_expression:
|
|
1114 fs->regs.cfa_exp = insn_ptr;
|
|
1115 fs->regs.cfa_how = CFA_EXP;
|
|
1116 insn_ptr = read_uleb128 (insn_ptr, &utmp);
|
|
1117 insn_ptr += utmp;
|
|
1118 break;
|
|
1119
|
|
1120 case DW_CFA_expression:
|
|
1121 insn_ptr = read_uleb128 (insn_ptr, ®);
|
|
1122 reg = DWARF_REG_TO_UNWIND_COLUMN (reg);
|
|
1123 if (UNWIND_COLUMN_IN_RANGE (reg))
|
|
1124 {
|
|
1125 fs->regs.reg[reg].how = REG_SAVED_EXP;
|
|
1126 fs->regs.reg[reg].loc.exp = insn_ptr;
|
|
1127 }
|
|
1128 insn_ptr = read_uleb128 (insn_ptr, &utmp);
|
|
1129 insn_ptr += utmp;
|
|
1130 break;
|
|
1131
|
|
1132 /* Dwarf3. */
|
|
1133 case DW_CFA_offset_extended_sf:
|
|
1134 insn_ptr = read_uleb128 (insn_ptr, ®);
|
|
1135 insn_ptr = read_sleb128 (insn_ptr, &stmp);
|
|
1136 offset = stmp * fs->data_align;
|
|
1137 reg = DWARF_REG_TO_UNWIND_COLUMN (reg);
|
|
1138 if (UNWIND_COLUMN_IN_RANGE (reg))
|
|
1139 {
|
|
1140 fs->regs.reg[reg].how = REG_SAVED_OFFSET;
|
|
1141 fs->regs.reg[reg].loc.offset = offset;
|
|
1142 }
|
|
1143 break;
|
|
1144
|
|
1145 case DW_CFA_def_cfa_sf:
|
|
1146 insn_ptr = read_uleb128 (insn_ptr, &utmp);
|
|
1147 fs->regs.cfa_reg = (_Unwind_Word)utmp;
|
|
1148 insn_ptr = read_sleb128 (insn_ptr, &stmp);
|
|
1149 fs->regs.cfa_offset = (_Unwind_Sword)stmp;
|
|
1150 fs->regs.cfa_how = CFA_REG_OFFSET;
|
|
1151 fs->regs.cfa_offset *= fs->data_align;
|
|
1152 break;
|
|
1153
|
|
1154 case DW_CFA_def_cfa_offset_sf:
|
|
1155 insn_ptr = read_sleb128 (insn_ptr, &stmp);
|
|
1156 fs->regs.cfa_offset = (_Unwind_Sword)stmp;
|
|
1157 fs->regs.cfa_offset *= fs->data_align;
|
|
1158 /* cfa_how deliberately not set. */
|
|
1159 break;
|
|
1160
|
|
1161 case DW_CFA_val_offset:
|
|
1162 insn_ptr = read_uleb128 (insn_ptr, ®);
|
|
1163 insn_ptr = read_uleb128 (insn_ptr, &utmp);
|
|
1164 offset = (_Unwind_Sword) utmp * fs->data_align;
|
|
1165 reg = DWARF_REG_TO_UNWIND_COLUMN (reg);
|
|
1166 if (UNWIND_COLUMN_IN_RANGE (reg))
|
|
1167 {
|
|
1168 fs->regs.reg[reg].how = REG_SAVED_VAL_OFFSET;
|
|
1169 fs->regs.reg[reg].loc.offset = offset;
|
|
1170 }
|
|
1171 break;
|
|
1172
|
|
1173 case DW_CFA_val_offset_sf:
|
|
1174 insn_ptr = read_uleb128 (insn_ptr, ®);
|
|
1175 insn_ptr = read_sleb128 (insn_ptr, &stmp);
|
|
1176 offset = stmp * fs->data_align;
|
|
1177 reg = DWARF_REG_TO_UNWIND_COLUMN (reg);
|
|
1178 if (UNWIND_COLUMN_IN_RANGE (reg))
|
|
1179 {
|
|
1180 fs->regs.reg[reg].how = REG_SAVED_VAL_OFFSET;
|
|
1181 fs->regs.reg[reg].loc.offset = offset;
|
|
1182 }
|
|
1183 break;
|
|
1184
|
|
1185 case DW_CFA_val_expression:
|
|
1186 insn_ptr = read_uleb128 (insn_ptr, ®);
|
|
1187 reg = DWARF_REG_TO_UNWIND_COLUMN (reg);
|
|
1188 if (UNWIND_COLUMN_IN_RANGE (reg))
|
|
1189 {
|
|
1190 fs->regs.reg[reg].how = REG_SAVED_VAL_EXP;
|
|
1191 fs->regs.reg[reg].loc.exp = insn_ptr;
|
|
1192 }
|
|
1193 insn_ptr = read_uleb128 (insn_ptr, &utmp);
|
|
1194 insn_ptr += utmp;
|
|
1195 break;
|
|
1196
|
|
1197 case DW_CFA_GNU_window_save:
|
|
1198 #if defined (__aarch64__) && !defined (__ILP32__)
|
|
1199 /* This CFA is multiplexed with Sparc. On AArch64 it's used to toggle
|
|
1200 return address signing status. */
|
|
1201 fs->regs.reg[DWARF_REGNUM_AARCH64_RA_STATE].loc.offset ^= 1;
|
|
1202 #else
|
|
1203 /* ??? Hardcoded for SPARC register window configuration. */
|
|
1204 if (__LIBGCC_DWARF_FRAME_REGISTERS__ >= 32)
|
|
1205 for (reg = 16; reg < 32; ++reg)
|
|
1206 {
|
|
1207 fs->regs.reg[reg].how = REG_SAVED_OFFSET;
|
|
1208 fs->regs.reg[reg].loc.offset = (reg - 16) * sizeof (void *);
|
|
1209 }
|
|
1210 #endif
|
|
1211 break;
|
|
1212
|
|
1213 case DW_CFA_GNU_args_size:
|
|
1214 insn_ptr = read_uleb128 (insn_ptr, &utmp);
|
|
1215 context->args_size = (_Unwind_Word)utmp;
|
|
1216 break;
|
|
1217
|
|
1218 case DW_CFA_GNU_negative_offset_extended:
|
|
1219 /* Obsoleted by DW_CFA_offset_extended_sf, but used by
|
|
1220 older PowerPC code. */
|
|
1221 insn_ptr = read_uleb128 (insn_ptr, ®);
|
|
1222 insn_ptr = read_uleb128 (insn_ptr, &utmp);
|
|
1223 offset = (_Unwind_Word) utmp * fs->data_align;
|
|
1224 reg = DWARF_REG_TO_UNWIND_COLUMN (reg);
|
|
1225 if (UNWIND_COLUMN_IN_RANGE (reg))
|
|
1226 {
|
|
1227 fs->regs.reg[reg].how = REG_SAVED_OFFSET;
|
|
1228 fs->regs.reg[reg].loc.offset = -offset;
|
|
1229 }
|
|
1230 break;
|
|
1231
|
|
1232 default:
|
|
1233 gcc_unreachable ();
|
|
1234 }
|
|
1235 }
|
|
1236 }
|
|
1237
|
|
1238 /* Given the _Unwind_Context CONTEXT for a stack frame, look up the FDE for
|
|
1239 its caller and decode it into FS. This function also sets the
|
|
1240 args_size and lsda members of CONTEXT, as they are really information
|
|
1241 about the caller's frame. */
|
|
1242
|
|
1243 static _Unwind_Reason_Code
|
|
1244 uw_frame_state_for (struct _Unwind_Context *context, _Unwind_FrameState *fs)
|
|
1245 {
|
|
1246 const struct dwarf_fde *fde;
|
|
1247 const struct dwarf_cie *cie;
|
|
1248 const unsigned char *aug, *insn, *end;
|
|
1249
|
|
1250 memset (fs, 0, sizeof (*fs));
|
|
1251 context->args_size = 0;
|
|
1252 context->lsda = 0;
|
|
1253
|
|
1254 if (context->ra == 0)
|
|
1255 return _URC_END_OF_STACK;
|
|
1256
|
|
1257 fde = _Unwind_Find_FDE (context->ra + _Unwind_IsSignalFrame (context) - 1,
|
|
1258 &context->bases);
|
|
1259 if (fde == NULL)
|
|
1260 {
|
|
1261 #ifdef MD_FALLBACK_FRAME_STATE_FOR
|
|
1262 /* Couldn't find frame unwind info for this function. Try a
|
|
1263 target-specific fallback mechanism. This will necessarily
|
|
1264 not provide a personality routine or LSDA. */
|
|
1265 return MD_FALLBACK_FRAME_STATE_FOR (context, fs);
|
|
1266 #else
|
|
1267 return _URC_END_OF_STACK;
|
|
1268 #endif
|
|
1269 }
|
|
1270
|
|
1271 fs->pc = context->bases.func;
|
|
1272
|
|
1273 cie = get_cie (fde);
|
|
1274 insn = extract_cie_info (cie, context, fs);
|
|
1275 if (insn == NULL)
|
|
1276 /* CIE contained unknown augmentation. */
|
|
1277 return _URC_FATAL_PHASE1_ERROR;
|
|
1278
|
|
1279 /* First decode all the insns in the CIE. */
|
|
1280 end = (const unsigned char *) next_fde ((const struct dwarf_fde *) cie);
|
|
1281 execute_cfa_program (insn, end, context, fs);
|
|
1282
|
|
1283 /* Locate augmentation for the fde. */
|
|
1284 aug = (const unsigned char *) fde + sizeof (*fde);
|
|
1285 aug += 2 * size_of_encoded_value (fs->fde_encoding);
|
|
1286 insn = NULL;
|
|
1287 if (fs->saw_z)
|
|
1288 {
|
|
1289 _uleb128_t i;
|
|
1290 aug = read_uleb128 (aug, &i);
|
|
1291 insn = aug + i;
|
|
1292 }
|
|
1293 if (fs->lsda_encoding != DW_EH_PE_omit)
|
|
1294 {
|
|
1295 _Unwind_Ptr lsda;
|
|
1296
|
|
1297 aug = read_encoded_value (context, fs->lsda_encoding, aug, &lsda);
|
|
1298 context->lsda = (void *) lsda;
|
|
1299 }
|
|
1300
|
|
1301 /* Then the insns in the FDE up to our target PC. */
|
|
1302 if (insn == NULL)
|
|
1303 insn = aug;
|
|
1304 end = (const unsigned char *) next_fde (fde);
|
|
1305 execute_cfa_program (insn, end, context, fs);
|
|
1306
|
|
1307 return _URC_NO_REASON;
|
|
1308 }
|
|
1309
|
|
1310 typedef struct frame_state
|
|
1311 {
|
|
1312 void *cfa;
|
|
1313 void *eh_ptr;
|
|
1314 long cfa_offset;
|
|
1315 long args_size;
|
|
1316 long reg_or_offset[PRE_GCC3_DWARF_FRAME_REGISTERS+1];
|
|
1317 unsigned short cfa_reg;
|
|
1318 unsigned short retaddr_column;
|
|
1319 char saved[PRE_GCC3_DWARF_FRAME_REGISTERS+1];
|
|
1320 } frame_state;
|
|
1321
|
|
1322 struct frame_state * __frame_state_for (void *, struct frame_state *);
|
|
1323
|
|
1324 /* Called from pre-G++ 3.0 __throw to find the registers to restore for
|
|
1325 a given PC_TARGET. The caller should allocate a local variable of
|
|
1326 `struct frame_state' and pass its address to STATE_IN. */
|
|
1327
|
|
1328 struct frame_state *
|
|
1329 __frame_state_for (void *pc_target, struct frame_state *state_in)
|
|
1330 {
|
|
1331 struct _Unwind_Context context;
|
|
1332 _Unwind_FrameState fs;
|
|
1333 int reg;
|
|
1334
|
|
1335 memset (&context, 0, sizeof (struct _Unwind_Context));
|
|
1336 if (!ASSUME_EXTENDED_UNWIND_CONTEXT)
|
|
1337 context.flags = EXTENDED_CONTEXT_BIT;
|
|
1338 context.ra = pc_target + 1;
|
|
1339
|
|
1340 if (uw_frame_state_for (&context, &fs) != _URC_NO_REASON)
|
|
1341 return 0;
|
|
1342
|
|
1343 /* We have no way to pass a location expression for the CFA to our
|
|
1344 caller. It wouldn't understand it anyway. */
|
|
1345 if (fs.regs.cfa_how == CFA_EXP)
|
|
1346 return 0;
|
|
1347
|
|
1348 for (reg = 0; reg < PRE_GCC3_DWARF_FRAME_REGISTERS + 1; reg++)
|
|
1349 {
|
|
1350 state_in->saved[reg] = fs.regs.reg[reg].how;
|
|
1351 switch (state_in->saved[reg])
|
|
1352 {
|
|
1353 case REG_SAVED_REG:
|
|
1354 state_in->reg_or_offset[reg] = fs.regs.reg[reg].loc.reg;
|
|
1355 break;
|
|
1356 case REG_SAVED_OFFSET:
|
|
1357 state_in->reg_or_offset[reg] = fs.regs.reg[reg].loc.offset;
|
|
1358 break;
|
|
1359 default:
|
|
1360 state_in->reg_or_offset[reg] = 0;
|
|
1361 break;
|
|
1362 }
|
|
1363 }
|
|
1364
|
|
1365 state_in->cfa_offset = fs.regs.cfa_offset;
|
|
1366 state_in->cfa_reg = fs.regs.cfa_reg;
|
|
1367 state_in->retaddr_column = fs.retaddr_column;
|
|
1368 state_in->args_size = context.args_size;
|
|
1369 state_in->eh_ptr = fs.eh_ptr;
|
|
1370
|
|
1371 return state_in;
|
|
1372 }
|
|
1373
|
|
1374 typedef union { _Unwind_Ptr ptr; _Unwind_Word word; } _Unwind_SpTmp;
|
|
1375
|
|
1376 static inline void
|
|
1377 _Unwind_SetSpColumn (struct _Unwind_Context *context, void *cfa,
|
|
1378 _Unwind_SpTmp *tmp_sp)
|
|
1379 {
|
|
1380 int size = dwarf_reg_size_table[__builtin_dwarf_sp_column ()];
|
|
1381
|
|
1382 if (size == sizeof(_Unwind_Ptr))
|
|
1383 tmp_sp->ptr = (_Unwind_Ptr) cfa;
|
|
1384 else
|
|
1385 {
|
|
1386 gcc_assert (size == sizeof(_Unwind_Word));
|
|
1387 tmp_sp->word = (_Unwind_Ptr) cfa;
|
|
1388 }
|
|
1389 _Unwind_SetGRPtr (context, __builtin_dwarf_sp_column (), tmp_sp);
|
|
1390 }
|
|
1391
|
|
1392 static void
|
|
1393 uw_update_context_1 (struct _Unwind_Context *context, _Unwind_FrameState *fs)
|
|
1394 {
|
|
1395 struct _Unwind_Context orig_context = *context;
|
|
1396 void *cfa;
|
|
1397 long i;
|
|
1398
|
|
1399 #ifdef __LIBGCC_EH_RETURN_STACKADJ_RTX__
|
|
1400 /* Special handling here: Many machines do not use a frame pointer,
|
|
1401 and track the CFA only through offsets from the stack pointer from
|
|
1402 one frame to the next. In this case, the stack pointer is never
|
|
1403 stored, so it has no saved address in the context. What we do
|
|
1404 have is the CFA from the previous stack frame.
|
|
1405
|
|
1406 In very special situations (such as unwind info for signal return),
|
|
1407 there may be location expressions that use the stack pointer as well.
|
|
1408
|
|
1409 Do this conditionally for one frame. This allows the unwind info
|
|
1410 for one frame to save a copy of the stack pointer from the previous
|
|
1411 frame, and be able to use much easier CFA mechanisms to do it.
|
|
1412 Always zap the saved stack pointer value for the next frame; carrying
|
|
1413 the value over from one frame to another doesn't make sense. */
|
|
1414
|
|
1415 _Unwind_SpTmp tmp_sp;
|
|
1416
|
|
1417 if (!_Unwind_GetGRPtr (&orig_context, __builtin_dwarf_sp_column ()))
|
|
1418 _Unwind_SetSpColumn (&orig_context, context->cfa, &tmp_sp);
|
|
1419 _Unwind_SetGRPtr (context, __builtin_dwarf_sp_column (), NULL);
|
|
1420 #endif
|
|
1421
|
|
1422 /* Compute this frame's CFA. */
|
|
1423 switch (fs->regs.cfa_how)
|
|
1424 {
|
|
1425 case CFA_REG_OFFSET:
|
|
1426 cfa = _Unwind_GetPtr (&orig_context, fs->regs.cfa_reg);
|
|
1427 cfa += fs->regs.cfa_offset;
|
|
1428 break;
|
|
1429
|
|
1430 case CFA_EXP:
|
|
1431 {
|
|
1432 const unsigned char *exp = fs->regs.cfa_exp;
|
|
1433 _uleb128_t len;
|
|
1434
|
|
1435 exp = read_uleb128 (exp, &len);
|
|
1436 cfa = (void *) (_Unwind_Ptr)
|
|
1437 execute_stack_op (exp, exp + len, &orig_context, 0);
|
|
1438 break;
|
|
1439 }
|
|
1440
|
|
1441 default:
|
|
1442 gcc_unreachable ();
|
|
1443 }
|
|
1444 context->cfa = cfa;
|
|
1445
|
|
1446 /* Compute the addresses of all registers saved in this frame. */
|
|
1447 for (i = 0; i < __LIBGCC_DWARF_FRAME_REGISTERS__ + 1; ++i)
|
|
1448 switch (fs->regs.reg[i].how)
|
|
1449 {
|
|
1450 case REG_UNSAVED:
|
|
1451 case REG_UNDEFINED:
|
|
1452 break;
|
|
1453
|
|
1454 case REG_SAVED_OFFSET:
|
|
1455 _Unwind_SetGRPtr (context, i,
|
|
1456 (void *) (cfa + fs->regs.reg[i].loc.offset));
|
|
1457 break;
|
|
1458
|
|
1459 case REG_SAVED_REG:
|
|
1460 if (_Unwind_GRByValue (&orig_context, fs->regs.reg[i].loc.reg))
|
|
1461 _Unwind_SetGRValue (context, i,
|
|
1462 _Unwind_GetGR (&orig_context,
|
|
1463 fs->regs.reg[i].loc.reg));
|
|
1464 else
|
|
1465 _Unwind_SetGRPtr (context, i,
|
|
1466 _Unwind_GetGRPtr (&orig_context,
|
|
1467 fs->regs.reg[i].loc.reg));
|
|
1468 break;
|
|
1469
|
|
1470 case REG_SAVED_EXP:
|
|
1471 {
|
|
1472 const unsigned char *exp = fs->regs.reg[i].loc.exp;
|
|
1473 _uleb128_t len;
|
|
1474 _Unwind_Ptr val;
|
|
1475
|
|
1476 exp = read_uleb128 (exp, &len);
|
|
1477 val = execute_stack_op (exp, exp + len, &orig_context,
|
|
1478 (_Unwind_Ptr) cfa);
|
|
1479 _Unwind_SetGRPtr (context, i, (void *) val);
|
|
1480 }
|
|
1481 break;
|
|
1482
|
|
1483 case REG_SAVED_VAL_OFFSET:
|
|
1484 _Unwind_SetGRValue (context, i,
|
|
1485 (_Unwind_Internal_Ptr)
|
|
1486 (cfa + fs->regs.reg[i].loc.offset));
|
|
1487 break;
|
|
1488
|
|
1489 case REG_SAVED_VAL_EXP:
|
|
1490 {
|
|
1491 const unsigned char *exp = fs->regs.reg[i].loc.exp;
|
|
1492 _uleb128_t len;
|
|
1493 _Unwind_Ptr val;
|
|
1494
|
|
1495 exp = read_uleb128 (exp, &len);
|
|
1496 val = execute_stack_op (exp, exp + len, &orig_context,
|
|
1497 (_Unwind_Ptr) cfa);
|
|
1498 _Unwind_SetGRValue (context, i, val);
|
|
1499 }
|
|
1500 break;
|
|
1501 }
|
|
1502
|
|
1503 _Unwind_SetSignalFrame (context, fs->signal_frame);
|
|
1504
|
|
1505 #ifdef MD_FROB_UPDATE_CONTEXT
|
|
1506 MD_FROB_UPDATE_CONTEXT (context, fs);
|
|
1507 #endif
|
|
1508 }
|
|
1509
|
|
1510 /* CONTEXT describes the unwind state for a frame, and FS describes the FDE
|
|
1511 of its caller. Update CONTEXT to refer to the caller as well. Note
|
|
1512 that the args_size and lsda members are not updated here, but later in
|
|
1513 uw_frame_state_for. */
|
|
1514
|
|
1515 static void
|
|
1516 uw_update_context (struct _Unwind_Context *context, _Unwind_FrameState *fs)
|
|
1517 {
|
|
1518 uw_update_context_1 (context, fs);
|
|
1519
|
|
1520 /* In general this unwinder doesn't make any distinction between
|
|
1521 undefined and same_value rule. Call-saved registers are assumed
|
|
1522 to have same_value rule by default and explicit undefined
|
|
1523 rule is handled like same_value. The only exception is
|
|
1524 DW_CFA_undefined on retaddr_column which is supposed to
|
|
1525 mark outermost frame in DWARF 3. */
|
|
1526 if (fs->regs.reg[DWARF_REG_TO_UNWIND_COLUMN (fs->retaddr_column)].how
|
|
1527 == REG_UNDEFINED)
|
|
1528 /* uw_frame_state_for uses context->ra == 0 check to find outermost
|
|
1529 stack frame. */
|
|
1530 context->ra = 0;
|
|
1531 else
|
|
1532 {
|
|
1533 /* Compute the return address now, since the return address column
|
|
1534 can change from frame to frame. */
|
|
1535 context->ra = __builtin_extract_return_addr
|
|
1536 (_Unwind_GetPtr (context, fs->retaddr_column));
|
|
1537 #ifdef MD_POST_EXTRACT_FRAME_ADDR
|
|
1538 context->ra = MD_POST_EXTRACT_FRAME_ADDR (context, fs, context->ra);
|
|
1539 #endif
|
|
1540 }
|
|
1541 }
|
|
1542
|
|
1543 static void
|
|
1544 uw_advance_context (struct _Unwind_Context *context, _Unwind_FrameState *fs)
|
|
1545 {
|
|
1546 uw_update_context (context, fs);
|
|
1547 }
|
|
1548
|
|
1549 /* Fill in CONTEXT for top-of-stack. The only valid registers at this
|
|
1550 level will be the return address and the CFA. */
|
|
1551
|
|
1552 #define uw_init_context(CONTEXT) \
|
|
1553 do \
|
|
1554 { \
|
|
1555 /* Do any necessary initialization to access arbitrary stack frames. \
|
|
1556 On the SPARC, this means flushing the register windows. */ \
|
|
1557 __builtin_unwind_init (); \
|
|
1558 uw_init_context_1 (CONTEXT, __builtin_dwarf_cfa (), \
|
|
1559 __builtin_return_address (0)); \
|
|
1560 } \
|
|
1561 while (0)
|
|
1562
|
|
1563 static inline void
|
|
1564 init_dwarf_reg_size_table (void)
|
|
1565 {
|
|
1566 __builtin_init_dwarf_reg_size_table (dwarf_reg_size_table);
|
|
1567 }
|
|
1568
|
|
1569 static void __attribute__((noinline))
|
|
1570 uw_init_context_1 (struct _Unwind_Context *context,
|
|
1571 void *outer_cfa, void *outer_ra)
|
|
1572 {
|
|
1573 void *ra = __builtin_extract_return_addr (__builtin_return_address (0));
|
|
1574 #ifdef MD_POST_EXTRACT_ROOT_ADDR
|
|
1575 ra = MD_POST_EXTRACT_ROOT_ADDR (ra);
|
|
1576 #endif
|
|
1577 _Unwind_FrameState fs;
|
|
1578 _Unwind_SpTmp sp_slot;
|
|
1579 _Unwind_Reason_Code code;
|
|
1580
|
|
1581 memset (context, 0, sizeof (struct _Unwind_Context));
|
|
1582 context->ra = ra;
|
|
1583 if (!ASSUME_EXTENDED_UNWIND_CONTEXT)
|
|
1584 context->flags = EXTENDED_CONTEXT_BIT;
|
|
1585
|
|
1586 code = uw_frame_state_for (context, &fs);
|
|
1587 gcc_assert (code == _URC_NO_REASON);
|
|
1588
|
|
1589 #if __GTHREADS
|
|
1590 {
|
|
1591 static __gthread_once_t once_regsizes = __GTHREAD_ONCE_INIT;
|
|
1592 if (__gthread_once (&once_regsizes, init_dwarf_reg_size_table) != 0
|
|
1593 && dwarf_reg_size_table[0] == 0)
|
|
1594 init_dwarf_reg_size_table ();
|
|
1595 }
|
|
1596 #else
|
|
1597 if (dwarf_reg_size_table[0] == 0)
|
|
1598 init_dwarf_reg_size_table ();
|
|
1599 #endif
|
|
1600
|
|
1601 /* Force the frame state to use the known cfa value. */
|
|
1602 _Unwind_SetSpColumn (context, outer_cfa, &sp_slot);
|
|
1603 fs.regs.cfa_how = CFA_REG_OFFSET;
|
|
1604 fs.regs.cfa_reg = __builtin_dwarf_sp_column ();
|
|
1605 fs.regs.cfa_offset = 0;
|
|
1606
|
|
1607 uw_update_context_1 (context, &fs);
|
|
1608
|
|
1609 /* If the return address column was saved in a register in the
|
|
1610 initialization context, then we can't see it in the given
|
|
1611 call frame data. So have the initialization context tell us. */
|
|
1612 context->ra = __builtin_extract_return_addr (outer_ra);
|
|
1613 #ifdef MD_POST_EXTRACT_ROOT_ADDR
|
|
1614 context->ra = MD_POST_EXTRACT_ROOT_ADDR (context->ra);
|
|
1615 #endif
|
|
1616 }
|
|
1617
|
|
1618 static void _Unwind_DebugHook (void *, void *)
|
|
1619 __attribute__ ((__noinline__, __used__, __noclone__));
|
|
1620
|
|
1621 /* This function is called during unwinding. It is intended as a hook
|
|
1622 for a debugger to intercept exceptions. CFA is the CFA of the
|
|
1623 target frame. HANDLER is the PC to which control will be
|
|
1624 transferred. */
|
|
1625 static void
|
|
1626 _Unwind_DebugHook (void *cfa __attribute__ ((__unused__)),
|
|
1627 void *handler __attribute__ ((__unused__)))
|
|
1628 {
|
|
1629 /* We only want to use stap probes starting with v3. Earlier
|
|
1630 versions added too much startup cost. */
|
|
1631 #if defined (HAVE_SYS_SDT_H) && defined (STAP_PROBE2) && _SDT_NOTE_TYPE >= 3
|
|
1632 STAP_PROBE2 (libgcc, unwind, cfa, handler);
|
|
1633 #else
|
|
1634 asm ("");
|
|
1635 #endif
|
|
1636 }
|
|
1637
|
|
1638 /* Frob exception handler's address kept in TARGET before installing into
|
|
1639 CURRENT context. */
|
|
1640
|
|
1641 static inline void *
|
|
1642 uw_frob_return_addr (struct _Unwind_Context *current
|
|
1643 __attribute__ ((__unused__)),
|
|
1644 struct _Unwind_Context *target)
|
|
1645 {
|
|
1646 void *ret_addr = __builtin_frob_return_addr (target->ra);
|
|
1647 #ifdef MD_POST_FROB_EH_HANDLER_ADDR
|
|
1648 ret_addr = MD_POST_FROB_EH_HANDLER_ADDR (current, target, ret_addr);
|
|
1649 #endif
|
|
1650 return ret_addr;
|
|
1651 }
|
|
1652
|
|
1653 /* Install TARGET into CURRENT so that we can return to it. This is a
|
|
1654 macro because __builtin_eh_return must be invoked in the context of
|
131
|
1655 our caller. FRAMES is a number of frames to be unwind.
|
|
1656 _Unwind_Frames_Extra is a macro to do additional work during unwinding
|
|
1657 if needed, for example shadow stack pointer adjustment for Intel CET
|
|
1658 technology. */
|
111
|
1659
|
131
|
1660 #define uw_install_context(CURRENT, TARGET, FRAMES) \
|
111
|
1661 do \
|
|
1662 { \
|
|
1663 long offset = uw_install_context_1 ((CURRENT), (TARGET)); \
|
|
1664 void *handler = uw_frob_return_addr ((CURRENT), (TARGET)); \
|
|
1665 _Unwind_DebugHook ((TARGET)->cfa, handler); \
|
131
|
1666 _Unwind_Frames_Extra (FRAMES); \
|
111
|
1667 __builtin_eh_return (offset, handler); \
|
|
1668 } \
|
|
1669 while (0)
|
|
1670
|
|
1671 static long
|
|
1672 uw_install_context_1 (struct _Unwind_Context *current,
|
|
1673 struct _Unwind_Context *target)
|
|
1674 {
|
|
1675 long i;
|
|
1676 _Unwind_SpTmp sp_slot;
|
|
1677
|
|
1678 /* If the target frame does not have a saved stack pointer,
|
|
1679 then set up the target's CFA. */
|
|
1680 if (!_Unwind_GetGRPtr (target, __builtin_dwarf_sp_column ()))
|
|
1681 _Unwind_SetSpColumn (target, target->cfa, &sp_slot);
|
|
1682
|
|
1683 for (i = 0; i < __LIBGCC_DWARF_FRAME_REGISTERS__; ++i)
|
|
1684 {
|
|
1685 void *c = (void *) (_Unwind_Internal_Ptr) current->reg[i];
|
|
1686 void *t = (void *) (_Unwind_Internal_Ptr)target->reg[i];
|
|
1687
|
|
1688 gcc_assert (current->by_value[i] == 0);
|
|
1689 if (target->by_value[i] && c)
|
|
1690 {
|
|
1691 _Unwind_Word w;
|
|
1692 _Unwind_Ptr p;
|
|
1693 if (dwarf_reg_size_table[i] == sizeof (_Unwind_Word))
|
|
1694 {
|
|
1695 w = (_Unwind_Internal_Ptr) t;
|
|
1696 memcpy (c, &w, sizeof (_Unwind_Word));
|
|
1697 }
|
|
1698 else
|
|
1699 {
|
|
1700 gcc_assert (dwarf_reg_size_table[i] == sizeof (_Unwind_Ptr));
|
|
1701 p = (_Unwind_Internal_Ptr) t;
|
|
1702 memcpy (c, &p, sizeof (_Unwind_Ptr));
|
|
1703 }
|
|
1704 }
|
|
1705 else if (t && c && t != c)
|
|
1706 memcpy (c, t, dwarf_reg_size_table[i]);
|
|
1707 }
|
|
1708
|
|
1709 /* If the current frame doesn't have a saved stack pointer, then we
|
|
1710 need to rely on EH_RETURN_STACKADJ_RTX to get our target stack
|
|
1711 pointer value reloaded. */
|
|
1712 if (!_Unwind_GetGRPtr (current, __builtin_dwarf_sp_column ()))
|
|
1713 {
|
|
1714 void *target_cfa;
|
|
1715
|
|
1716 target_cfa = _Unwind_GetPtr (target, __builtin_dwarf_sp_column ());
|
|
1717
|
|
1718 /* We adjust SP by the difference between CURRENT and TARGET's CFA. */
|
|
1719 if (__LIBGCC_STACK_GROWS_DOWNWARD__)
|
|
1720 return target_cfa - current->cfa + target->args_size;
|
|
1721 else
|
|
1722 return current->cfa - target_cfa - target->args_size;
|
|
1723 }
|
|
1724 return 0;
|
|
1725 }
|
|
1726
|
|
1727 static inline _Unwind_Ptr
|
|
1728 uw_identify_context (struct _Unwind_Context *context)
|
|
1729 {
|
|
1730 /* The CFA is not sufficient to disambiguate the context of a function
|
|
1731 interrupted by a signal before establishing its frame and the context
|
|
1732 of the signal itself. */
|
|
1733 if (__LIBGCC_STACK_GROWS_DOWNWARD__)
|
|
1734 return _Unwind_GetCFA (context) - _Unwind_IsSignalFrame (context);
|
|
1735 else
|
|
1736 return _Unwind_GetCFA (context) + _Unwind_IsSignalFrame (context);
|
|
1737 }
|
|
1738
|
|
1739
|
|
1740 #include "unwind.inc"
|
|
1741
|
|
1742 #if defined (USE_GAS_SYMVER) && defined (SHARED) && defined (USE_LIBUNWIND_EXCEPTIONS)
|
|
1743 alias (_Unwind_Backtrace);
|
|
1744 alias (_Unwind_DeleteException);
|
|
1745 alias (_Unwind_FindEnclosingFunction);
|
|
1746 alias (_Unwind_ForcedUnwind);
|
|
1747 alias (_Unwind_GetDataRelBase);
|
|
1748 alias (_Unwind_GetTextRelBase);
|
|
1749 alias (_Unwind_GetCFA);
|
|
1750 alias (_Unwind_GetGR);
|
|
1751 alias (_Unwind_GetIP);
|
|
1752 alias (_Unwind_GetLanguageSpecificData);
|
|
1753 alias (_Unwind_GetRegionStart);
|
|
1754 alias (_Unwind_RaiseException);
|
|
1755 alias (_Unwind_Resume);
|
|
1756 alias (_Unwind_Resume_or_Rethrow);
|
|
1757 alias (_Unwind_SetGR);
|
|
1758 alias (_Unwind_SetIP);
|
|
1759 #endif
|
|
1760
|
|
1761 #endif /* !USING_SJLJ_EXCEPTIONS */
|