1 | /* Handle exceptional things in C++. |
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2 | Copyright (C) 1989, 1992, 1993, 1994, 1995 Free Software Foundation, Inc. |
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3 | Contributed by Michael Tiemann <tiemann@cygnus.com> |
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4 | Rewritten by Mike Stump <mrs@cygnus.com>, based upon an |
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5 | initial re-implementation courtesy Tad Hunt. |
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6 | |
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7 | This file is part of GNU CC. |
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8 | |
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9 | GNU CC is free software; you can redistribute it and/or modify |
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10 | it under the terms of the GNU General Public License as published by |
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11 | the Free Software Foundation; either version 2, or (at your option) |
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12 | any later version. |
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13 | |
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14 | GNU CC is distributed in the hope that it will be useful, |
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15 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
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16 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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17 | GNU General Public License for more details. |
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18 | |
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19 | You should have received a copy of the GNU General Public License |
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20 | along with GNU CC; see the file COPYING. If not, write to |
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21 | the Free Software Foundation, 59 Temple Place - Suite 330, |
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22 | Boston, MA 02111-1307, USA. */ |
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23 | |
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24 | |
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25 | /* High-level class interface. */ |
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26 | |
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27 | #include "config.h" |
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28 | #include "tree.h" |
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29 | #include "rtl.h" |
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30 | #include "cp-tree.h" |
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31 | #include "flags.h" |
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32 | #include "obstack.h" |
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33 | #include "expr.h" |
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34 | |
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35 | tree protect_list; |
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36 | |
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37 | extern void (*interim_eh_hook) PROTO((tree)); |
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38 | rtx expand_builtin_return_addr PROTO((enum built_in_function, int, rtx)); |
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39 | |
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40 | /* holds the fndecl for __builtin_return_address () */ |
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41 | tree builtin_return_address_fndecl; |
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42 | tree throw_fndecl; |
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43 | |
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44 | static int |
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45 | doing_eh (do_warn) |
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46 | int do_warn; |
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47 | { |
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48 | if (! flag_handle_exceptions) |
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49 | { |
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50 | static int warned = 0; |
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51 | if (! warned && do_warn) |
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52 | { |
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53 | error ("exception handling disabled, use -fhandle-exceptions to enable."); |
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54 | warned = 1; |
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55 | } |
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56 | return 0; |
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57 | } |
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58 | return 1; |
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59 | } |
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60 | |
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61 | |
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62 | /* |
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63 | NO GNEWS IS GOOD GNEWS WITH GARRY GNUS: This version is much closer |
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64 | to supporting exception handling as per ANSI C++ working draft. |
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65 | It is a complete rewrite of all the EH stuff that was here before |
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66 | Shortcomings: |
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67 | 1. Throw specifications of functions still don't work. |
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68 | Cool Things: |
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69 | 1. Destructors are called properly :-) |
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70 | 2. No overhead for the non-exception thrown case. |
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71 | 3. Fixing shortcoming 1 is simple. |
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72 | -Tad Hunt (tad@mail.csh.rit.edu) |
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73 | |
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74 | */ |
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75 | |
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76 | /* A couple of backend routines from m88k.c */ |
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77 | |
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78 | /* used to cache a call to __builtin_return_address () */ |
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79 | static tree BuiltinReturnAddress; |
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80 | |
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81 | |
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82 | #include <stdio.h> |
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83 | |
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84 | /* XXX - Tad: for EH */ |
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85 | /* output an exception table entry */ |
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86 | |
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87 | static void |
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88 | output_exception_table_entry (file, start_label, end_label, eh_label) |
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89 | FILE *file; |
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90 | rtx start_label, end_label, eh_label; |
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91 | { |
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92 | char label[100]; |
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93 | |
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94 | assemble_integer (start_label, GET_MODE_SIZE (Pmode), 1); |
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95 | assemble_integer (end_label, GET_MODE_SIZE (Pmode), 1); |
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96 | assemble_integer (eh_label, GET_MODE_SIZE (Pmode), 1); |
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97 | putc ('\n', file); /* blank line */ |
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98 | } |
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99 | |
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100 | static void |
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101 | easy_expand_asm (str) |
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102 | char *str; |
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103 | { |
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104 | expand_asm (build_string (strlen (str)+1, str)); |
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105 | } |
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106 | |
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107 | |
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108 | #if 0 |
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109 | /* This is the startup, and finish stuff per exception table. */ |
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110 | |
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111 | /* XXX - Tad: exception handling section */ |
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112 | #ifndef EXCEPT_SECTION_ASM_OP |
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113 | #define EXCEPT_SECTION_ASM_OP "section\t.gcc_except_table,\"a\",@progbits" |
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114 | #endif |
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115 | |
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116 | #ifdef EXCEPT_SECTION_ASM_OP |
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117 | typedef struct { |
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118 | void *start_protect; |
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119 | void *end_protect; |
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120 | void *exception_handler; |
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121 | } exception_table; |
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122 | #endif /* EXCEPT_SECTION_ASM_OP */ |
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123 | |
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124 | #ifdef EXCEPT_SECTION_ASM_OP |
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125 | |
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126 | /* on machines which support it, the exception table lives in another section, |
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127 | but it needs a label so we can reference it... This sets up that |
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128 | label! */ |
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129 | asm (EXCEPT_SECTION_ASM_OP); |
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130 | exception_table __EXCEPTION_TABLE__[1] = { (void*)0, (void*)0, (void*)0 }; |
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131 | asm (TEXT_SECTION_ASM_OP); |
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132 | |
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133 | #endif /* EXCEPT_SECTION_ASM_OP */ |
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134 | |
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135 | #ifdef EXCEPT_SECTION_ASM_OP |
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136 | |
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137 | /* we need to know where the end of the exception table is... so this |
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138 | is how we do it! */ |
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139 | |
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140 | asm (EXCEPT_SECTION_ASM_OP); |
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141 | exception_table __EXCEPTION_END__[1] = { (void*)-1, (void*)-1, (void*)-1 }; |
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142 | asm (TEXT_SECTION_ASM_OP); |
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143 | |
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144 | #endif /* EXCEPT_SECTION_ASM_OP */ |
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145 | |
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146 | #endif |
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147 | |
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148 | void |
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149 | exception_section () |
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150 | { |
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151 | #ifdef ASM_OUTPUT_SECTION_NAME |
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152 | named_section (NULL_TREE, ".gcc_except_table"); |
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153 | #else |
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154 | if (flag_pic) |
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155 | data_section (); |
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156 | else |
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157 | #if defined(TARGET_POWERPC) /* are we on a __rs6000? */ |
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158 | data_section (); |
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159 | #else |
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160 | readonly_data_section (); |
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161 | #endif |
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162 | #endif |
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163 | } |
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164 | |
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165 | |
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166 | |
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167 | |
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168 | /* from: my-cp-except.c */ |
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169 | |
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170 | /* VI: ":set ts=4" */ |
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171 | #if 0 |
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172 | #include <stdio.h> */ |
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173 | #include "config.h" |
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174 | #include "tree.h" |
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175 | #include "rtl.h" |
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176 | #include "cp-tree.h" |
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177 | #endif |
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178 | #include "decl.h" |
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179 | #if 0 |
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180 | #include "flags.h" |
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181 | #endif |
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182 | #include "insn-flags.h" |
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183 | #include "obstack.h" |
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184 | #if 0 |
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185 | #include "expr.h" |
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186 | #endif |
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187 | |
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188 | /* ====================================================================== |
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189 | Briefly the algorithm works like this: |
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190 | |
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191 | When a constructor or start of a try block is encountered, |
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192 | push_eh_entry (&eh_stack) is called. Push_eh_entry () creates a |
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193 | new entry in the unwind protection stack and returns a label to |
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194 | output to start the protection for that block. |
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195 | |
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196 | When a destructor or end try block is encountered, pop_eh_entry |
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197 | (&eh_stack) is called. Pop_eh_entry () returns the ehEntry it |
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198 | created when push_eh_entry () was called. The ehEntry structure |
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199 | contains three things at this point. The start protect label, |
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200 | the end protect label, and the exception handler label. The end |
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201 | protect label should be output before the call to the destructor |
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202 | (if any). If it was a destructor, then its parse tree is stored |
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203 | in the finalization variable in the ehEntry structure. Otherwise |
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204 | the finalization variable is set to NULL to reflect the fact that |
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205 | is the the end of a try block. Next, this modified ehEntry node |
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206 | is enqueued in the finalizations queue by calling |
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207 | enqueue_eh_entry (&queue,entry). |
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208 | |
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209 | +---------------------------------------------------------------+ |
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210 | |XXX: Will need modification to deal with partially | |
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211 | | constructed arrays of objects | |
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212 | | | |
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213 | | Basically, this consists of keeping track of how many | |
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214 | | of the objects have been constructed already (this | |
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215 | | should be in a register though, so that shouldn't be a | |
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216 | | problem. | |
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217 | +---------------------------------------------------------------+ |
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218 | |
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219 | When a catch block is encountered, there is a lot of work to be |
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220 | done. |
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221 | |
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222 | Since we don't want to generate the catch block inline with the |
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223 | regular flow of the function, we need to have some way of doing |
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224 | so. Luckily, we can use sequences to defer the catch sections. |
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225 | When the start of a catch block is encountered, we start the |
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226 | sequence. After the catch block is generated, we end the |
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227 | sequence. |
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228 | |
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229 | Next we must insure that when the catch block is executed, all |
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230 | finalizations for the matching try block have been completed. If |
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231 | any of those finalizations throw an exception, we must call |
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232 | terminate according to the ARM (section r.15.6.1). What this |
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233 | means is that we need to dequeue and emit finalizations for each |
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234 | entry in the ehQueue until we get to an entry with a NULL |
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235 | finalization field. For any of the finalization entries, if it |
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236 | is not a call to terminate (), we must protect it by giving it |
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237 | another start label, end label, and exception handler label, |
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238 | setting its finalization tree to be a call to terminate (), and |
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239 | enqueue'ing this new ehEntry to be output at an outer level. |
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240 | Finally, after all that is done, we can get around to outputting |
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241 | the catch block which basically wraps all the "catch (...) {...}" |
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242 | statements in a big if/then/else construct that matches the |
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243 | correct block to call. |
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244 | |
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245 | ===================================================================== */ |
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246 | |
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247 | extern rtx emit_insn PROTO((rtx)); |
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248 | extern rtx gen_nop PROTO(()); |
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249 | |
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250 | /* local globals for function calls |
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251 | ====================================================================== */ |
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252 | |
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253 | /* used to cache "terminate ()", "unexpected ()", "set_terminate ()", and |
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254 | "set_unexpected ()" after default_conversion. (lib-except.c) */ |
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255 | static tree Terminate, Unexpected, SetTerminate, SetUnexpected, CatchMatch, Throw; |
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256 | |
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257 | /* used to cache __find_first_exception_table_match () |
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258 | for throw (lib-except.c) */ |
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259 | static tree FirstExceptionMatch; |
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260 | |
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261 | /* used to cache a call to __unwind_function () (lib-except.c) */ |
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262 | static tree Unwind; |
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263 | |
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264 | /* holds a ready to emit call to "terminate ()". */ |
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265 | static tree TerminateFunctionCall; |
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266 | |
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267 | /* ====================================================================== */ |
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268 | |
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269 | |
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270 | |
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271 | /* data structures for my various quick and dirty stacks and queues |
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272 | Eventually, most of this should go away, because I think it can be |
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273 | integrated with stuff already built into the compiler. */ |
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274 | |
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275 | /* =================================================================== */ |
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276 | |
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277 | struct labelNode { |
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278 | rtx label; |
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279 | struct labelNode *chain; |
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280 | }; |
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281 | |
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282 | |
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283 | /* this is the most important structure here. Basically this is how I store |
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284 | an exception table entry internally. */ |
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285 | struct ehEntry { |
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286 | rtx start_label; |
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287 | rtx end_label; |
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288 | rtx exception_handler_label; |
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289 | |
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290 | tree finalization; |
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291 | tree context; |
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292 | }; |
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293 | |
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294 | struct ehNode { |
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295 | struct ehEntry *entry; |
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296 | struct ehNode *chain; |
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297 | }; |
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298 | |
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299 | struct ehStack { |
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300 | struct ehNode *top; |
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301 | }; |
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302 | |
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303 | struct ehQueue { |
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304 | struct ehNode *head; |
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305 | struct ehNode *tail; |
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306 | }; |
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307 | /* ========================================================================= */ |
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308 | |
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309 | |
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310 | |
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311 | /* local globals - these local globals are for storing data necessary for |
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312 | generating the exception table and code in the correct order. |
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313 | |
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314 | ========================================================================= */ |
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315 | |
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316 | /* Holds the pc for doing "throw" */ |
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317 | tree saved_pc; |
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318 | /* Holds the type of the thing being thrown. */ |
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319 | tree saved_throw_type; |
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320 | /* Holds the value being thrown. */ |
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321 | tree saved_throw_value; |
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322 | |
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323 | int throw_used; |
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324 | |
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325 | static rtx catch_clauses; |
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326 | static first_catch_label; |
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327 | |
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328 | static struct ehStack ehstack; |
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329 | static struct ehQueue ehqueue; |
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330 | static struct ehQueue eh_table_output_queue; |
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331 | static struct labelNode *false_label_stack = NULL; |
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332 | static struct labelNode *caught_return_label_stack = NULL; |
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333 | /* ========================================================================= */ |
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334 | |
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335 | /* function prototypes */ |
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336 | static struct ehEntry *pop_eh_entry PROTO((struct ehStack *stack)); |
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337 | static void enqueue_eh_entry PROTO((struct ehQueue *queue, struct ehEntry *entry)); |
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338 | static rtx push_eh_entry PROTO((struct ehStack *stack)); |
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339 | static struct ehEntry *dequeue_eh_entry PROTO((struct ehQueue *queue)); |
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340 | static void new_eh_queue PROTO((struct ehQueue *queue)); |
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341 | static void new_eh_stack PROTO((struct ehStack *stack)); |
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342 | static void push_label_entry PROTO((struct labelNode **labelstack, rtx label)); |
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343 | static rtx pop_label_entry PROTO((struct labelNode **labelstack)); |
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344 | static rtx top_label_entry PROTO((struct labelNode **labelstack)); |
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345 | static struct ehEntry *copy_eh_entry PROTO((struct ehEntry *entry)); |
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346 | |
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347 | |
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348 | |
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349 | /* All my cheesy stack/queue/misc data structure handling routines |
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350 | |
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351 | ========================================================================= */ |
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352 | |
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353 | static void |
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354 | push_label_entry (labelstack, label) |
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355 | struct labelNode **labelstack; |
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356 | rtx label; |
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357 | { |
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358 | struct labelNode *newnode=(struct labelNode*)xmalloc (sizeof (struct labelNode)); |
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359 | |
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360 | newnode->label = label; |
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361 | newnode->chain = *labelstack; |
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362 | *labelstack = newnode; |
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363 | } |
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364 | |
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365 | static rtx |
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366 | pop_label_entry (labelstack) |
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367 | struct labelNode **labelstack; |
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368 | { |
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369 | rtx label; |
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370 | struct labelNode *tempnode; |
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371 | |
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372 | if (! *labelstack) return NULL_RTX; |
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373 | |
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374 | tempnode = *labelstack; |
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375 | label = tempnode->label; |
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376 | *labelstack = (*labelstack)->chain; |
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377 | free (tempnode); |
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378 | |
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379 | return label; |
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380 | } |
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381 | |
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382 | static rtx |
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383 | top_label_entry (labelstack) |
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384 | struct labelNode **labelstack; |
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385 | { |
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386 | if (! *labelstack) return NULL_RTX; |
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387 | |
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388 | return (*labelstack)->label; |
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389 | } |
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390 | |
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391 | /* Push to permanent obstack for rtl generation. |
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392 | One level only! */ |
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393 | static struct obstack *saved_rtl_obstack; |
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394 | void |
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395 | push_rtl_perm () |
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396 | { |
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397 | extern struct obstack permanent_obstack; |
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398 | extern struct obstack *rtl_obstack; |
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399 | |
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400 | saved_rtl_obstack = rtl_obstack; |
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401 | rtl_obstack = &permanent_obstack; |
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402 | } |
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403 | |
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404 | /* Pop back to normal rtl handling. */ |
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405 | static void |
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406 | pop_rtl_from_perm () |
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407 | { |
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408 | extern struct obstack permanent_obstack; |
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409 | extern struct obstack *rtl_obstack; |
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410 | |
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411 | rtl_obstack = saved_rtl_obstack; |
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412 | } |
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413 | |
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414 | static rtx |
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415 | push_eh_entry (stack) |
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416 | struct ehStack *stack; |
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417 | { |
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418 | struct ehNode *node = (struct ehNode*)xmalloc (sizeof (struct ehNode)); |
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419 | struct ehEntry *entry = (struct ehEntry*)xmalloc (sizeof (struct ehEntry)); |
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420 | |
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421 | if (stack == NULL) { |
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422 | free (node); |
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423 | free (entry); |
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424 | return NULL_RTX; |
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425 | } |
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426 | |
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427 | /* These are saved for the exception table. */ |
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428 | push_rtl_perm (); |
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429 | entry->start_label = gen_label_rtx (); |
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430 | entry->end_label = gen_label_rtx (); |
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431 | entry->exception_handler_label = gen_label_rtx (); |
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432 | pop_rtl_from_perm (); |
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433 | |
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434 | LABEL_PRESERVE_P (entry->start_label) = 1; |
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435 | LABEL_PRESERVE_P (entry->end_label) = 1; |
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436 | LABEL_PRESERVE_P (entry->exception_handler_label) = 1; |
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437 | |
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438 | entry->finalization = NULL_TREE; |
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439 | entry->context = current_function_decl; |
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440 | |
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441 | node->entry = entry; |
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442 | node->chain = stack->top; |
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443 | stack->top = node; |
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444 | |
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445 | enqueue_eh_entry (&eh_table_output_queue, copy_eh_entry (entry)); |
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446 | |
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447 | return entry->start_label; |
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448 | } |
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449 | |
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450 | static struct ehEntry * |
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451 | pop_eh_entry (stack) |
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452 | struct ehStack *stack; |
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453 | { |
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454 | struct ehNode *tempnode; |
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455 | struct ehEntry *tempentry; |
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456 | |
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457 | if (stack && (tempnode = stack->top)) { |
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458 | tempentry = tempnode->entry; |
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459 | stack->top = stack->top->chain; |
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460 | free (tempnode); |
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461 | |
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462 | return tempentry; |
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463 | } |
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464 | |
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465 | return NULL; |
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466 | } |
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467 | |
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468 | static struct ehEntry * |
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469 | copy_eh_entry (entry) |
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470 | struct ehEntry *entry; |
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471 | { |
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472 | struct ehEntry *newentry; |
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473 | |
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474 | newentry = (struct ehEntry*)xmalloc (sizeof (struct ehEntry)); |
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475 | memcpy ((void*)newentry, (void*)entry, sizeof (struct ehEntry)); |
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476 | |
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477 | return newentry; |
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478 | } |
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479 | |
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480 | static void |
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481 | enqueue_eh_entry (queue, entry) |
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482 | struct ehQueue *queue; |
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483 | struct ehEntry *entry; |
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484 | { |
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485 | struct ehNode *node = (struct ehNode*)xmalloc (sizeof (struct ehNode)); |
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486 | |
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487 | node->entry = entry; |
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488 | node->chain = NULL; |
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489 | |
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490 | if (queue->head == NULL) |
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491 | { |
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492 | queue->head = node; |
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493 | } |
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494 | else |
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495 | { |
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496 | queue->tail->chain = node; |
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497 | } |
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498 | queue->tail = node; |
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499 | } |
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500 | |
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501 | static struct ehEntry * |
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502 | dequeue_eh_entry (queue) |
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503 | struct ehQueue *queue; |
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504 | { |
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505 | struct ehNode *tempnode; |
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506 | struct ehEntry *tempentry; |
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507 | |
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508 | if (queue->head == NULL) |
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509 | return NULL; |
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510 | |
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511 | tempnode = queue->head; |
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512 | queue->head = queue->head->chain; |
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513 | |
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514 | tempentry = tempnode->entry; |
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515 | free (tempnode); |
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516 | |
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517 | return tempentry; |
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518 | } |
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519 | |
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520 | static void |
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521 | new_eh_queue (queue) |
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522 | struct ehQueue *queue; |
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523 | { |
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524 | queue->head = queue->tail = NULL; |
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525 | } |
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526 | |
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527 | static void |
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528 | new_eh_stack (stack) |
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529 | struct ehStack *stack; |
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530 | { |
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531 | stack->top = NULL; |
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532 | } |
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533 | |
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534 | /* cheesyness to save some typing. returns the return value rtx */ |
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535 | rtx |
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536 | do_function_call (func, params, return_type) |
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537 | tree func, params, return_type; |
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538 | { |
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539 | tree func_call; |
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540 | func_call = build_function_call (func, params); |
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541 | expand_call (func_call, NULL_RTX, 0); |
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542 | if (return_type != NULL_TREE) |
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543 | return hard_function_value (return_type, func_call); |
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544 | return NULL_RTX; |
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545 | } |
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546 | |
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547 | static void |
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548 | expand_internal_throw (pc) |
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549 | rtx pc; |
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550 | { |
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551 | tree params; |
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552 | |
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553 | emit_move_insn (DECL_RTL (saved_pc), pc); |
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554 | #ifdef JUMP_TO_THROW |
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555 | emit_indirect_jump (gen_rtx (SYMBOL_REF, Pmode, "__throw")); |
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556 | #else |
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557 | do_function_call (Throw, NULL_TREE, NULL_TREE); |
---|
558 | #endif |
---|
559 | throw_used = 1; |
---|
560 | } |
---|
561 | |
---|
562 | /* ========================================================================= */ |
---|
563 | |
---|
564 | void |
---|
565 | lang_interim_eh (finalization) |
---|
566 | tree finalization; |
---|
567 | { |
---|
568 | if (finalization) |
---|
569 | end_protect (finalization); |
---|
570 | else |
---|
571 | start_protect (); |
---|
572 | } |
---|
573 | |
---|
574 | extern tree auto_function PROTO((tree, tree, enum built_in_function)); |
---|
575 | |
---|
576 | /* sets up all the global eh stuff that needs to be initialized at the |
---|
577 | start of compilation. |
---|
578 | |
---|
579 | This includes: |
---|
580 | - Setting up all the function call trees |
---|
581 | - Initializing the ehqueue |
---|
582 | - Initializing the eh_table_output_queue |
---|
583 | - Initializing the ehstack |
---|
584 | */ |
---|
585 | |
---|
586 | void |
---|
587 | init_exception_processing () |
---|
588 | { |
---|
589 | extern tree define_function (); |
---|
590 | tree unexpected_fndecl, terminate_fndecl; |
---|
591 | tree set_unexpected_fndecl, set_terminate_fndecl; |
---|
592 | tree catch_match_fndecl; |
---|
593 | tree find_first_exception_match_fndecl; |
---|
594 | tree unwind_fndecl; |
---|
595 | tree declspecs; |
---|
596 | tree d; |
---|
597 | |
---|
598 | /* void (*)() */ |
---|
599 | tree PFV = build_pointer_type (build_function_type |
---|
600 | (void_type_node, void_list_node)); |
---|
601 | |
---|
602 | /* arg list for the build_function_type call for set_terminate () and |
---|
603 | set_unexpected () */ |
---|
604 | tree pfvlist = tree_cons (NULL_TREE, PFV, void_list_node); |
---|
605 | |
---|
606 | /* void (*pfvtype (void (*) ()))() */ |
---|
607 | tree pfvtype = build_function_type (PFV, pfvlist); |
---|
608 | |
---|
609 | /* void vtype () */ |
---|
610 | tree vtype = build_function_type (void_type_node, void_list_node); |
---|
611 | |
---|
612 | set_terminate_fndecl = auto_function (get_identifier ("set_terminate"), |
---|
613 | pfvtype, NOT_BUILT_IN); |
---|
614 | set_unexpected_fndecl = auto_function (get_identifier ("set_unexpected"), |
---|
615 | pfvtype, NOT_BUILT_IN); |
---|
616 | unexpected_fndecl = auto_function (get_identifier ("unexpected"), |
---|
617 | vtype, NOT_BUILT_IN); |
---|
618 | terminate_fndecl = auto_function (get_identifier ("terminate"), |
---|
619 | vtype, NOT_BUILT_IN); |
---|
620 | |
---|
621 | interim_eh_hook = lang_interim_eh; |
---|
622 | |
---|
623 | push_lang_context (lang_name_c); |
---|
624 | |
---|
625 | catch_match_fndecl = |
---|
626 | define_function (flag_rtti |
---|
627 | ? "__throw_type_match_rtti" |
---|
628 | : "__throw_type_match", |
---|
629 | build_function_type (ptr_type_node, |
---|
630 | tree_cons (NULL_TREE, ptr_type_node, |
---|
631 | tree_cons (NULL_TREE, ptr_type_node, |
---|
632 | tree_cons (NULL_TREE, ptr_type_node, |
---|
633 | void_list_node)))), |
---|
634 | NOT_BUILT_IN, |
---|
635 | pushdecl, |
---|
636 | 0); |
---|
637 | find_first_exception_match_fndecl = |
---|
638 | define_function ("__find_first_exception_table_match", |
---|
639 | build_function_type (ptr_type_node, |
---|
640 | tree_cons (NULL_TREE, ptr_type_node, |
---|
641 | void_list_node)), |
---|
642 | NOT_BUILT_IN, |
---|
643 | pushdecl, |
---|
644 | 0); |
---|
645 | unwind_fndecl = |
---|
646 | define_function ("__unwind_function", |
---|
647 | build_function_type (void_type_node, |
---|
648 | tree_cons (NULL_TREE, ptr_type_node, |
---|
649 | void_list_node)), |
---|
650 | NOT_BUILT_IN, |
---|
651 | pushdecl, |
---|
652 | 0); |
---|
653 | throw_fndecl = |
---|
654 | define_function ("__throw", |
---|
655 | build_function_type (void_type_node, void_list_node), |
---|
656 | NOT_BUILT_IN, |
---|
657 | pushdecl, |
---|
658 | 0); |
---|
659 | DECL_EXTERNAL (throw_fndecl) = 0; |
---|
660 | TREE_PUBLIC (throw_fndecl) = 0; |
---|
661 | |
---|
662 | Unexpected = default_conversion (unexpected_fndecl); |
---|
663 | Terminate = default_conversion (terminate_fndecl); |
---|
664 | SetTerminate = default_conversion (set_terminate_fndecl); |
---|
665 | SetUnexpected = default_conversion (set_unexpected_fndecl); |
---|
666 | CatchMatch = default_conversion (catch_match_fndecl); |
---|
667 | FirstExceptionMatch = default_conversion (find_first_exception_match_fndecl); |
---|
668 | Unwind = default_conversion (unwind_fndecl); |
---|
669 | Throw = default_conversion (throw_fndecl); |
---|
670 | BuiltinReturnAddress = default_conversion (builtin_return_address_fndecl); |
---|
671 | |
---|
672 | TerminateFunctionCall = build_function_call (Terminate, NULL_TREE); |
---|
673 | |
---|
674 | pop_lang_context (); |
---|
675 | |
---|
676 | new_eh_queue (&ehqueue); |
---|
677 | new_eh_queue (&eh_table_output_queue); |
---|
678 | new_eh_stack (&ehstack); |
---|
679 | |
---|
680 | declspecs = tree_cons (NULL_TREE, get_identifier ("void"), NULL_TREE); |
---|
681 | d = build_parse_node (INDIRECT_REF, get_identifier ("__eh_pc")); |
---|
682 | d = start_decl (d, declspecs, 0, NULL_TREE); |
---|
683 | DECL_COMMON (d) = 1; |
---|
684 | cp_finish_decl (d, NULL_TREE, NULL_TREE, 0, 0); |
---|
685 | saved_pc = lookup_name (get_identifier ("__eh_pc"), 0); |
---|
686 | |
---|
687 | declspecs = tree_cons (NULL_TREE, get_identifier ("void"), NULL_TREE); |
---|
688 | d = build_parse_node (INDIRECT_REF, get_identifier ("__eh_type")); |
---|
689 | d = start_decl (d, declspecs, 0, NULL_TREE); |
---|
690 | DECL_COMMON (d) = 1; |
---|
691 | cp_finish_decl (d, NULL_TREE, NULL_TREE, 0, 0); |
---|
692 | saved_throw_type = lookup_name (get_identifier ("__eh_type"), 0); |
---|
693 | |
---|
694 | declspecs = tree_cons (NULL_TREE, get_identifier ("void"), NULL_TREE); |
---|
695 | d = build_parse_node (INDIRECT_REF, get_identifier ("__eh_value")); |
---|
696 | d = start_decl (d, declspecs, 0, NULL_TREE); |
---|
697 | DECL_COMMON (d) = 1; |
---|
698 | cp_finish_decl (d, NULL_TREE, NULL_TREE, 0, 0); |
---|
699 | saved_throw_value = lookup_name (get_identifier ("__eh_value"), 0); |
---|
700 | } |
---|
701 | |
---|
702 | /* call this to begin a block of unwind protection (ie: when an object is |
---|
703 | constructed) */ |
---|
704 | void |
---|
705 | start_protect () |
---|
706 | { |
---|
707 | if (! doing_eh (0)) |
---|
708 | return; |
---|
709 | |
---|
710 | emit_label (push_eh_entry (&ehstack)); |
---|
711 | } |
---|
712 | |
---|
713 | /* call this to end a block of unwind protection. the finalization tree is |
---|
714 | the finalization which needs to be run in order to cleanly unwind through |
---|
715 | this level of protection. (ie: call this when a scope is exited)*/ |
---|
716 | void |
---|
717 | end_protect (finalization) |
---|
718 | tree finalization; |
---|
719 | { |
---|
720 | struct ehEntry *entry; |
---|
721 | |
---|
722 | if (! doing_eh (0)) |
---|
723 | return; |
---|
724 | |
---|
725 | entry = pop_eh_entry (&ehstack); |
---|
726 | |
---|
727 | emit_label (entry->end_label); |
---|
728 | /* Put in something that takes up space, as otherwise the end |
---|
729 | address for the EH region could have the exact same address as |
---|
730 | the outer region, causing us to miss the fact that resuming |
---|
731 | exception handling with this PC value would be inside the outer |
---|
732 | region. */ |
---|
733 | emit_insn (gen_nop ()); |
---|
734 | |
---|
735 | entry->finalization = finalization; |
---|
736 | |
---|
737 | enqueue_eh_entry (&ehqueue, entry); |
---|
738 | } |
---|
739 | |
---|
740 | /* call this on start of a try block. */ |
---|
741 | void |
---|
742 | expand_start_try_stmts () |
---|
743 | { |
---|
744 | if (! doing_eh (1)) |
---|
745 | return; |
---|
746 | |
---|
747 | start_protect (); |
---|
748 | } |
---|
749 | |
---|
750 | void |
---|
751 | expand_end_try_stmts () |
---|
752 | { |
---|
753 | end_protect (integer_zero_node); |
---|
754 | } |
---|
755 | |
---|
756 | |
---|
757 | /* call this to start processing of all the catch blocks. */ |
---|
758 | void |
---|
759 | expand_start_all_catch () |
---|
760 | { |
---|
761 | struct ehEntry *entry; |
---|
762 | rtx label; |
---|
763 | |
---|
764 | if (! doing_eh (1)) |
---|
765 | return; |
---|
766 | |
---|
767 | emit_line_note (input_filename, lineno); |
---|
768 | label = gen_label_rtx (); |
---|
769 | |
---|
770 | /* The label for the exception handling block we will save. This is |
---|
771 | Lresume, in the documention. */ |
---|
772 | emit_label (label); |
---|
773 | |
---|
774 | /* Put in something that takes up space, as otherwise the end |
---|
775 | address for the EH region could have the exact same address as |
---|
776 | the outer region, causing us to miss the fact that resuming |
---|
777 | exception handling with this PC value would be inside the outer |
---|
778 | region. */ |
---|
779 | emit_insn (gen_nop ()); |
---|
780 | |
---|
781 | push_label_entry (&caught_return_label_stack, label); |
---|
782 | |
---|
783 | /* Start a new sequence for all the catch blocks. We will add this |
---|
784 | to the gloabl sequence catch_clauses, when we have completed all |
---|
785 | the handlers in this handler-seq. */ |
---|
786 | start_sequence (); |
---|
787 | |
---|
788 | while (1) |
---|
789 | { |
---|
790 | entry = dequeue_eh_entry (&ehqueue); |
---|
791 | emit_label (entry->exception_handler_label); |
---|
792 | |
---|
793 | expand_expr (entry->finalization, const0_rtx, VOIDmode, 0); |
---|
794 | |
---|
795 | /* When we get down to the matching entry, stop. */ |
---|
796 | if (entry->finalization == integer_zero_node) |
---|
797 | break; |
---|
798 | |
---|
799 | /* The below can be optimized away, and we could just fall into the |
---|
800 | next EH handler, if we are certain they are nested. */ |
---|
801 | /* Code to throw out to outer context, if we fall off end of the |
---|
802 | handler. */ |
---|
803 | expand_internal_throw (gen_rtx (LABEL_REF, |
---|
804 | Pmode, |
---|
805 | entry->end_label)); |
---|
806 | free (entry); |
---|
807 | } |
---|
808 | } |
---|
809 | |
---|
810 | /* call this to end processing of all the catch blocks. */ |
---|
811 | void |
---|
812 | expand_end_all_catch () |
---|
813 | { |
---|
814 | rtx new_catch_clause; |
---|
815 | |
---|
816 | if (! doing_eh (1)) |
---|
817 | return; |
---|
818 | |
---|
819 | /* Code to throw out to outer context, if we fall off end of catch |
---|
820 | handlers. This is rethrow (Lresume, same id, same obj); in the |
---|
821 | documentation. */ |
---|
822 | expand_internal_throw (gen_rtx (LABEL_REF, |
---|
823 | Pmode, |
---|
824 | top_label_entry (&caught_return_label_stack))); |
---|
825 | |
---|
826 | /* Now we have the complete catch sequence. */ |
---|
827 | new_catch_clause = get_insns (); |
---|
828 | end_sequence (); |
---|
829 | |
---|
830 | /* this level of catch blocks is done, so set up the successful catch jump |
---|
831 | label for the next layer of catch blocks. */ |
---|
832 | pop_label_entry (&caught_return_label_stack); |
---|
833 | |
---|
834 | /* Add the new sequence of catchs to the main one for this |
---|
835 | function. */ |
---|
836 | push_to_sequence (catch_clauses); |
---|
837 | emit_insns (new_catch_clause); |
---|
838 | catch_clauses = get_insns (); |
---|
839 | end_sequence (); |
---|
840 | |
---|
841 | /* Here we fall through into the continuation code. */ |
---|
842 | } |
---|
843 | |
---|
844 | /* Build a type value for use at runtime for a type that is matched |
---|
845 | against by the exception handling system. */ |
---|
846 | static tree |
---|
847 | build_eh_type_type (type) |
---|
848 | tree type; |
---|
849 | { |
---|
850 | char *typestring; |
---|
851 | tree exp; |
---|
852 | |
---|
853 | if (type == error_mark_node) |
---|
854 | return error_mark_node; |
---|
855 | |
---|
856 | /* peel back references, so they match. */ |
---|
857 | if (TREE_CODE (type) == REFERENCE_TYPE) |
---|
858 | type = TREE_TYPE (type); |
---|
859 | |
---|
860 | /* Peel off cv qualifiers. */ |
---|
861 | type = TYPE_MAIN_VARIANT (type); |
---|
862 | |
---|
863 | if (flag_rtti) |
---|
864 | { |
---|
865 | return build1 (ADDR_EXPR, ptr_type_node, get_typeid (type)); |
---|
866 | } |
---|
867 | |
---|
868 | typestring = build_overload_name (type, 1, 1); |
---|
869 | exp = combine_strings (build_string (strlen (typestring)+1, typestring)); |
---|
870 | return build1 (ADDR_EXPR, ptr_type_node, exp); |
---|
871 | } |
---|
872 | |
---|
873 | /* Build a type value for use at runtime for a exp that is thrown or |
---|
874 | matched against by the exception handling system. */ |
---|
875 | static tree |
---|
876 | build_eh_type (exp) |
---|
877 | tree exp; |
---|
878 | { |
---|
879 | if (flag_rtti) |
---|
880 | { |
---|
881 | exp = build_typeid (exp); |
---|
882 | return build1 (ADDR_EXPR, ptr_type_node, exp); |
---|
883 | } |
---|
884 | return build_eh_type_type (TREE_TYPE (exp)); |
---|
885 | } |
---|
886 | |
---|
887 | /* call this to start a catch block. Typename is the typename, and identifier |
---|
888 | is the variable to place the object in or NULL if the variable doesn't |
---|
889 | matter. If typename is NULL, that means its a "catch (...)" or catch |
---|
890 | everything. In that case we don't need to do any type checking. |
---|
891 | (ie: it ends up as the "else" clause rather than an "else if" clause) */ |
---|
892 | void |
---|
893 | expand_start_catch_block (declspecs, declarator) |
---|
894 | tree declspecs, declarator; |
---|
895 | { |
---|
896 | rtx false_label_rtx; |
---|
897 | rtx protect_label_rtx; |
---|
898 | tree decl = NULL_TREE; |
---|
899 | tree init; |
---|
900 | |
---|
901 | if (! doing_eh (1)) |
---|
902 | return; |
---|
903 | |
---|
904 | /* Create a binding level for the parm. */ |
---|
905 | expand_start_bindings (0); |
---|
906 | |
---|
907 | false_label_rtx = gen_label_rtx (); |
---|
908 | /* This is saved for the exception table. */ |
---|
909 | push_rtl_perm (); |
---|
910 | protect_label_rtx = gen_label_rtx (); |
---|
911 | pop_rtl_from_perm (); |
---|
912 | push_label_entry (&false_label_stack, false_label_rtx); |
---|
913 | push_label_entry (&false_label_stack, protect_label_rtx); |
---|
914 | |
---|
915 | if (declspecs) |
---|
916 | { |
---|
917 | tree exp; |
---|
918 | rtx call_rtx, return_value_rtx; |
---|
919 | tree init_type; |
---|
920 | |
---|
921 | decl = grokdeclarator (declarator, declspecs, CATCHPARM, 1, |
---|
922 | NULL_TREE, NULL_TREE); |
---|
923 | |
---|
924 | if (decl == NULL_TREE) |
---|
925 | { |
---|
926 | error ("invalid catch parameter"); |
---|
927 | return; |
---|
928 | } |
---|
929 | |
---|
930 | /* Figure out the type that the initializer is. */ |
---|
931 | init_type = TREE_TYPE (decl); |
---|
932 | if (TREE_CODE (init_type) != REFERENCE_TYPE |
---|
933 | && TREE_CODE (init_type) != POINTER_TYPE) |
---|
934 | init_type = build_reference_type (init_type); |
---|
935 | |
---|
936 | exp = saved_throw_value; |
---|
937 | exp = tree_cons (NULL_TREE, |
---|
938 | build_eh_type_type (TREE_TYPE (decl)), |
---|
939 | tree_cons (NULL_TREE, |
---|
940 | saved_throw_type, |
---|
941 | tree_cons (NULL_TREE, exp, NULL_TREE))); |
---|
942 | exp = build_function_call (CatchMatch, exp); |
---|
943 | call_rtx = expand_call (exp, NULL_RTX, 0); |
---|
944 | assemble_external (TREE_OPERAND (CatchMatch, 0)); |
---|
945 | |
---|
946 | return_value_rtx = hard_function_value (ptr_type_node, exp); |
---|
947 | |
---|
948 | /* did the throw type match function return TRUE? */ |
---|
949 | emit_cmp_insn (return_value_rtx, const0_rtx, EQ, NULL_RTX, |
---|
950 | GET_MODE (return_value_rtx), 0, 0); |
---|
951 | |
---|
952 | /* if it returned FALSE, jump over the catch block, else fall into it */ |
---|
953 | emit_jump_insn (gen_beq (false_label_rtx)); |
---|
954 | |
---|
955 | init = convert_from_reference (save_expr (make_tree (init_type, call_rtx))); |
---|
956 | |
---|
957 | /* Do we need the below two lines? */ |
---|
958 | /* Let `cp_finish_decl' know that this initializer is ok. */ |
---|
959 | DECL_INITIAL (decl) = init; |
---|
960 | decl = pushdecl (decl); |
---|
961 | cp_finish_decl (decl, init, NULL_TREE, 0, LOOKUP_ONLYCONVERTING); |
---|
962 | } |
---|
963 | else |
---|
964 | { |
---|
965 | /* Fall into the catch all section. */ |
---|
966 | } |
---|
967 | |
---|
968 | /* This is the starting of something to protect. */ |
---|
969 | emit_label (protect_label_rtx); |
---|
970 | |
---|
971 | emit_line_note (input_filename, lineno); |
---|
972 | } |
---|
973 | |
---|
974 | |
---|
975 | /* this is called from expand_exception_blocks and |
---|
976 | expand_end_catch_block to expand the toplevel finalizations for a |
---|
977 | function. We return the first label emitted, if any, otherwise |
---|
978 | return NULL_RTX. */ |
---|
979 | static rtx |
---|
980 | expand_leftover_cleanups () |
---|
981 | { |
---|
982 | struct ehEntry *entry; |
---|
983 | rtx first_label = NULL_RTX; |
---|
984 | |
---|
985 | while ((entry = dequeue_eh_entry (&ehqueue)) != 0) |
---|
986 | { |
---|
987 | if (! first_label) |
---|
988 | first_label = entry->exception_handler_label; |
---|
989 | emit_label (entry->exception_handler_label); |
---|
990 | |
---|
991 | expand_expr (entry->finalization, const0_rtx, VOIDmode, 0); |
---|
992 | |
---|
993 | /* The below can be optimized away, and we could just fall into the |
---|
994 | next EH handler, if we are certain they are nested. */ |
---|
995 | /* Code to throw out to outer context, if we fall off end of the |
---|
996 | handler. */ |
---|
997 | expand_internal_throw (gen_rtx (LABEL_REF, |
---|
998 | Pmode, |
---|
999 | entry->end_label)); |
---|
1000 | |
---|
1001 | /* leftover try block, opps. */ |
---|
1002 | if (entry->finalization == integer_zero_node) |
---|
1003 | abort (); |
---|
1004 | |
---|
1005 | free (entry); |
---|
1006 | } |
---|
1007 | |
---|
1008 | return first_label; |
---|
1009 | } |
---|
1010 | |
---|
1011 | /* Call this to end a catch block. Its responsible for emitting the |
---|
1012 | code to handle jumping back to the correct place, and for emitting |
---|
1013 | the label to jump to if this catch block didn't match. */ |
---|
1014 | void expand_end_catch_block () |
---|
1015 | { |
---|
1016 | rtx start_protect_label_rtx; |
---|
1017 | rtx end_protect_label_rtx; |
---|
1018 | tree decls; |
---|
1019 | struct ehEntry entry; |
---|
1020 | |
---|
1021 | if (! doing_eh (1)) |
---|
1022 | return; |
---|
1023 | |
---|
1024 | /* fall to outside the try statement when done executing handler and |
---|
1025 | we fall off end of handler. This is jump Lresume in the |
---|
1026 | documentation. */ |
---|
1027 | emit_jump (top_label_entry (&caught_return_label_stack)); |
---|
1028 | |
---|
1029 | /* We end the rethrow protection region as soon as we hit a label. */ |
---|
1030 | end_protect_label_rtx = expand_leftover_cleanups (); |
---|
1031 | |
---|
1032 | /* Code to throw out to outer context, if we get a throw from within |
---|
1033 | our catch handler. */ |
---|
1034 | /* These are saved for the exception table. */ |
---|
1035 | push_rtl_perm (); |
---|
1036 | entry.exception_handler_label = gen_label_rtx (); |
---|
1037 | pop_rtl_from_perm (); |
---|
1038 | /* This label is Lhandler in the documentation. */ |
---|
1039 | emit_label (entry.exception_handler_label); |
---|
1040 | expand_internal_throw (gen_rtx (LABEL_REF, |
---|
1041 | Pmode, |
---|
1042 | top_label_entry (&caught_return_label_stack))); |
---|
1043 | |
---|
1044 | /* No associated finalization. */ |
---|
1045 | entry.finalization = NULL_TREE; |
---|
1046 | entry.context = current_function_decl; |
---|
1047 | |
---|
1048 | if (end_protect_label_rtx == NULL_RTX) |
---|
1049 | end_protect_label_rtx = entry.exception_handler_label; |
---|
1050 | |
---|
1051 | /* Because we are emitted out of line, we have to protect this. */ |
---|
1052 | /* label for the start of the protection region. */ |
---|
1053 | start_protect_label_rtx = pop_label_entry (&false_label_stack); |
---|
1054 | |
---|
1055 | /* Cleanup the EH parameter. */ |
---|
1056 | decls = getdecls (); |
---|
1057 | expand_end_bindings (decls, decls != NULL_TREE, 0); |
---|
1058 | |
---|
1059 | /* label we emit to jump to if this catch block didn't match. */ |
---|
1060 | /* This the closing } in the `if (eq) {' of the documentation. */ |
---|
1061 | emit_label (pop_label_entry (&false_label_stack)); |
---|
1062 | |
---|
1063 | /* Because we are reordered out of line, we have to protect this. */ |
---|
1064 | entry.start_label = start_protect_label_rtx; |
---|
1065 | entry.end_label = end_protect_label_rtx; |
---|
1066 | |
---|
1067 | LABEL_PRESERVE_P (entry.start_label) = 1; |
---|
1068 | LABEL_PRESERVE_P (entry.end_label) = 1; |
---|
1069 | LABEL_PRESERVE_P (entry.exception_handler_label) = 1; |
---|
1070 | |
---|
1071 | /* These set up a call to throw the caught exception into the outer |
---|
1072 | context. */ |
---|
1073 | enqueue_eh_entry (&eh_table_output_queue, copy_eh_entry (&entry)); |
---|
1074 | } |
---|
1075 | |
---|
1076 | /* unwind the stack. */ |
---|
1077 | static void |
---|
1078 | do_unwind (inner_throw_label) |
---|
1079 | rtx inner_throw_label; |
---|
1080 | { |
---|
1081 | #if defined(SPARC_STACK_ALIGN) /* was sparc */ |
---|
1082 | tree fcall; |
---|
1083 | tree params; |
---|
1084 | rtx return_val_rtx; |
---|
1085 | rtx temp; |
---|
1086 | |
---|
1087 | /* call to __builtin_return_address () */ |
---|
1088 | params = tree_cons (NULL_TREE, integer_zero_node, NULL_TREE); |
---|
1089 | fcall = build_function_call (BuiltinReturnAddress, params); |
---|
1090 | return_val_rtx = expand_expr (fcall, NULL_RTX, Pmode, 0); |
---|
1091 | /* In the return, the new pc is pc+8, as the value coming in is |
---|
1092 | really the address of the call insn, not the next insn. */ |
---|
1093 | temp = gen_reg_rtx (Pmode); |
---|
1094 | emit_move_insn (temp, inner_throw_label); |
---|
1095 | emit_move_insn (return_val_rtx, plus_constant (temp, -8)); |
---|
1096 | easy_expand_asm ("ret"); |
---|
1097 | easy_expand_asm ("restore"); |
---|
1098 | emit_barrier (); |
---|
1099 | #endif |
---|
1100 | #if defined(ARM_FRAME_RTX) /* was __arm */ |
---|
1101 | if (flag_omit_frame_pointer) |
---|
1102 | sorry ("this implementation of exception handling requires a frame pointer"); |
---|
1103 | |
---|
1104 | emit_move_insn (stack_pointer_rtx, |
---|
1105 | gen_rtx (MEM, Pmode, plus_constant (hard_frame_pointer_rtx, -8))); |
---|
1106 | emit_move_insn (hard_frame_pointer_rtx, |
---|
1107 | gen_rtx (MEM, Pmode, plus_constant (hard_frame_pointer_rtx, -12))); |
---|
1108 | #endif |
---|
1109 | #if defined(TARGET_88000) /* was m88k */ |
---|
1110 | rtx temp_frame = frame_pointer_rtx; |
---|
1111 | |
---|
1112 | temp_frame = memory_address (Pmode, temp_frame); |
---|
1113 | temp_frame = copy_to_reg (gen_rtx (MEM, Pmode, temp_frame)); |
---|
1114 | |
---|
1115 | /* hopefully this will successfully pop the frame! */ |
---|
1116 | emit_move_insn (frame_pointer_rtx, temp_frame); |
---|
1117 | emit_move_insn (stack_pointer_rtx, frame_pointer_rtx); |
---|
1118 | emit_move_insn (arg_pointer_rtx, frame_pointer_rtx); |
---|
1119 | emit_insn (gen_add2_insn (stack_pointer_rtx, gen_rtx (CONST_INT, VOIDmode, |
---|
1120 | (HOST_WIDE_INT)m88k_debugger_offset (stack_pointer_rtx, 0)))); |
---|
1121 | |
---|
1122 | #if 0 |
---|
1123 | emit_insn (gen_add2_insn (arg_pointer_rtx, gen_rtx (CONST_INT, VOIDmode, |
---|
1124 | -(HOST_WIDE_INT)m88k_debugger_offset (arg_pointer_rtx, 0)))); |
---|
1125 | |
---|
1126 | emit_move_insn (stack_pointer_rtx, arg_pointer_rtx); |
---|
1127 | |
---|
1128 | emit_insn (gen_add2_insn (stack_pointer_rtx, gen_rtx (CONST_INT, VOIDmode, |
---|
1129 | (HOST_WIDE_INT)m88k_debugger_offset (arg_pointer_rtx, 0)))); |
---|
1130 | #endif |
---|
1131 | #endif |
---|
1132 | #if !defined(TARGET_88000) && !defined(ARM_FRAME_RTX) && !defined(SPARC_STACK_ALIGN) |
---|
1133 | tree fcall; |
---|
1134 | tree params; |
---|
1135 | rtx return_val_rtx; |
---|
1136 | |
---|
1137 | /* call to __builtin_return_address () */ |
---|
1138 | params = tree_cons (NULL_TREE, integer_zero_node, NULL_TREE); |
---|
1139 | fcall = build_function_call (BuiltinReturnAddress, params); |
---|
1140 | return_val_rtx = expand_expr (fcall, NULL_RTX, Pmode, 0); |
---|
1141 | #if 0 |
---|
1142 | /* I would like to do this here, but doesn't seem to work. */ |
---|
1143 | emit_move_insn (return_val_rtx, inner_throw_label); |
---|
1144 | /* So, for now, just pass throw label to stack unwinder. */ |
---|
1145 | #endif |
---|
1146 | params = tree_cons (NULL_TREE, make_tree (ptr_type_node, |
---|
1147 | inner_throw_label), NULL_TREE); |
---|
1148 | |
---|
1149 | do_function_call (Unwind, params, NULL_TREE); |
---|
1150 | assemble_external (TREE_OPERAND (Unwind, 0)); |
---|
1151 | emit_barrier (); |
---|
1152 | #endif |
---|
1153 | } |
---|
1154 | |
---|
1155 | |
---|
1156 | /* is called from expand_exception_blocks () to generate the code in a function |
---|
1157 | to "throw" if anything in the function needs to perform a throw. |
---|
1158 | |
---|
1159 | expands "throw" as the following pseudo code: |
---|
1160 | |
---|
1161 | throw: |
---|
1162 | eh = find_first_exception_match (saved_pc); |
---|
1163 | if (!eh) goto gotta_rethrow_it; |
---|
1164 | goto eh; |
---|
1165 | |
---|
1166 | gotta_rethrow_it: |
---|
1167 | saved_pc = __builtin_return_address (0); |
---|
1168 | pop_to_previous_level (); |
---|
1169 | goto throw; |
---|
1170 | |
---|
1171 | */ |
---|
1172 | void |
---|
1173 | expand_builtin_throw () |
---|
1174 | { |
---|
1175 | tree fcall; |
---|
1176 | tree params; |
---|
1177 | rtx return_val_rtx; |
---|
1178 | rtx gotta_rethrow_it; |
---|
1179 | rtx gotta_call_terminate; |
---|
1180 | rtx unwind_and_throw; |
---|
1181 | rtx goto_unwind_and_throw; |
---|
1182 | rtx top_of_loop; |
---|
1183 | rtx unwind_first; |
---|
1184 | tree t; |
---|
1185 | |
---|
1186 | if (! doing_eh (0)) |
---|
1187 | return; |
---|
1188 | |
---|
1189 | if (! throw_used) |
---|
1190 | return; |
---|
1191 | |
---|
1192 | params = void_list_node; |
---|
1193 | t = build_parse_node (CALL_EXPR, get_identifier ("__throw"), params, NULL_TREE); |
---|
1194 | start_function (decl_tree_cons (NULL_TREE, get_identifier ("static"), |
---|
1195 | void_list_node), |
---|
1196 | t, NULL_TREE, NULL_TREE, 0); |
---|
1197 | store_parm_decls (); |
---|
1198 | pushlevel (0); |
---|
1199 | clear_last_expr (); |
---|
1200 | push_momentary (); |
---|
1201 | expand_start_bindings (0); |
---|
1202 | |
---|
1203 | gotta_rethrow_it = gen_label_rtx (); |
---|
1204 | gotta_call_terminate = gen_label_rtx (); |
---|
1205 | unwind_and_throw = gen_label_rtx (); |
---|
1206 | goto_unwind_and_throw = gen_label_rtx (); |
---|
1207 | top_of_loop = gen_label_rtx (); |
---|
1208 | unwind_first = gen_label_rtx (); |
---|
1209 | |
---|
1210 | emit_jump (unwind_first); |
---|
1211 | |
---|
1212 | emit_label (top_of_loop); |
---|
1213 | |
---|
1214 | /* search for an exception handler for the saved_pc */ |
---|
1215 | return_val_rtx = do_function_call (FirstExceptionMatch, |
---|
1216 | tree_cons (NULL_TREE, saved_pc, NULL_TREE), |
---|
1217 | ptr_type_node); |
---|
1218 | assemble_external (TREE_OPERAND (FirstExceptionMatch, 0)); |
---|
1219 | |
---|
1220 | /* did we find one? */ |
---|
1221 | emit_cmp_insn (return_val_rtx, const0_rtx, EQ, NULL_RTX, |
---|
1222 | GET_MODE (return_val_rtx), 0, 0); |
---|
1223 | |
---|
1224 | /* if not, jump to gotta_rethrow_it */ |
---|
1225 | emit_jump_insn (gen_beq (gotta_rethrow_it)); |
---|
1226 | |
---|
1227 | /* we found it, so jump to it */ |
---|
1228 | emit_indirect_jump (return_val_rtx); |
---|
1229 | |
---|
1230 | /* code to deal with unwinding and looking for it again */ |
---|
1231 | emit_label (gotta_rethrow_it); |
---|
1232 | |
---|
1233 | /* call to __builtin_return_address () */ |
---|
1234 | #if defined(ARM_FRAME_RTX) /* was __arm */ |
---|
1235 | /* This replaces a 'call' to __builtin_return_address */ |
---|
1236 | return_val_rtx = gen_reg_rtx (Pmode); |
---|
1237 | emit_move_insn (return_val_rtx, gen_rtx (MEM, Pmode, plus_constant (hard_frame_pointer_rtx, -4))); |
---|
1238 | #else |
---|
1239 | params = tree_cons (NULL_TREE, integer_zero_node, NULL_TREE); |
---|
1240 | fcall = build_function_call (BuiltinReturnAddress, params); |
---|
1241 | return_val_rtx = expand_expr (fcall, NULL_RTX, Pmode, 0); |
---|
1242 | #endif |
---|
1243 | |
---|
1244 | /* did __builtin_return_address () return a valid address? */ |
---|
1245 | emit_cmp_insn (return_val_rtx, const0_rtx, EQ, NULL_RTX, |
---|
1246 | GET_MODE (return_val_rtx), 0, 0); |
---|
1247 | |
---|
1248 | emit_jump_insn (gen_beq (gotta_call_terminate)); |
---|
1249 | |
---|
1250 | #if defined(ARM_FRAME_RTX) /* was __arm */ |
---|
1251 | /* On the ARM, '__builtin_return_address', must have 4 |
---|
1252 | subtracted from it. */ |
---|
1253 | emit_insn (gen_add2_insn (return_val_rtx, GEN_INT (-4))); |
---|
1254 | |
---|
1255 | /* If we are generating code for an ARM2/ARM3 machine or for an ARM6 in 26 bit |
---|
1256 | mode, the condition codes must be masked out of the return value, or else |
---|
1257 | they will confuse BuiltinReturnAddress. This does not apply to ARM6 and |
---|
1258 | later processors when running in 32 bit mode. */ |
---|
1259 | if (!TARGET_6) |
---|
1260 | emit_insn (gen_rtx (SET, Pmode, return_val_rtx, gen_rtx (AND, Pmode, return_val_rtx, GEN_INT (0x03fffffc)))); |
---|
1261 | #else |
---|
1262 | #if !defined(SPARC_STACK_ALIGN) /* was sparc */ |
---|
1263 | /* On the SPARC, __builtin_return_address is already -8, no need to |
---|
1264 | subtract any more from it. */ |
---|
1265 | return_val_rtx = plus_constant (return_val_rtx, -1); |
---|
1266 | #endif |
---|
1267 | #endif |
---|
1268 | |
---|
1269 | /* yes it did */ |
---|
1270 | t = build_modify_expr (saved_pc, NOP_EXPR, make_tree (ptr_type_node, return_val_rtx)); |
---|
1271 | expand_expr (t, const0_rtx, VOIDmode, 0); |
---|
1272 | |
---|
1273 | do_unwind (gen_rtx (LABEL_REF, Pmode, top_of_loop)); |
---|
1274 | emit_jump (top_of_loop); |
---|
1275 | |
---|
1276 | /* no it didn't --> therefore we need to call terminate */ |
---|
1277 | emit_label (gotta_call_terminate); |
---|
1278 | do_function_call (Terminate, NULL_TREE, NULL_TREE); |
---|
1279 | assemble_external (TREE_OPERAND (Terminate, 0)); |
---|
1280 | |
---|
1281 | { |
---|
1282 | rtx ret_val, return_val_rtx; |
---|
1283 | emit_label (unwind_first); |
---|
1284 | ret_val = expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS, |
---|
1285 | 0, hard_frame_pointer_rtx); |
---|
1286 | |
---|
1287 | /* Set it up so that we continue inside, at the top of the loop. */ |
---|
1288 | emit_move_insn (ret_val, gen_rtx (LABEL_REF, Pmode, top_of_loop)); |
---|
1289 | #ifdef NORMAL_RETURN_ADDR_OFFSET |
---|
1290 | return_val_rtx = plus_constant (ret_val, -NORMAL_RETURN_ADDR_OFFSET); |
---|
1291 | if (return_val_rtx != ret_val) |
---|
1292 | emit_move_insn (ret_val, return_val_rtx); |
---|
1293 | #endif |
---|
1294 | |
---|
1295 | /* Fall into epilogue to unwind prologue. */ |
---|
1296 | } |
---|
1297 | |
---|
1298 | expand_end_bindings (getdecls(), 1, 0); |
---|
1299 | poplevel (1, 0, 0); |
---|
1300 | pop_momentary (); |
---|
1301 | |
---|
1302 | finish_function (lineno, 0, 0); |
---|
1303 | } |
---|
1304 | |
---|
1305 | |
---|
1306 | void |
---|
1307 | expand_start_eh_spec () |
---|
1308 | { |
---|
1309 | start_protect (); |
---|
1310 | } |
---|
1311 | |
---|
1312 | void |
---|
1313 | expand_end_eh_spec (raises) |
---|
1314 | tree raises; |
---|
1315 | { |
---|
1316 | tree expr, second_try; |
---|
1317 | rtx check = gen_label_rtx (); |
---|
1318 | rtx cont; |
---|
1319 | rtx ret = gen_reg_rtx (Pmode); |
---|
1320 | rtx flag = gen_reg_rtx (TYPE_MODE (integer_type_node)); |
---|
1321 | rtx end = gen_label_rtx (); |
---|
1322 | |
---|
1323 | expr = make_node (RTL_EXPR); |
---|
1324 | TREE_TYPE (expr) = void_type_node; |
---|
1325 | RTL_EXPR_RTL (expr) = const0_rtx; |
---|
1326 | TREE_SIDE_EFFECTS (expr) = 1; |
---|
1327 | start_sequence_for_rtl_expr (expr); |
---|
1328 | cont = gen_label_rtx (); |
---|
1329 | emit_move_insn (ret, gen_rtx (LABEL_REF, Pmode, cont)); |
---|
1330 | emit_jump (check); |
---|
1331 | emit_label (cont); |
---|
1332 | jumpif (make_tree (integer_type_node, flag), end); |
---|
1333 | do_function_call (Terminate, NULL_TREE, NULL_TREE); |
---|
1334 | assemble_external (TREE_OPERAND (Terminate, 0)); |
---|
1335 | emit_barrier (); |
---|
1336 | RTL_EXPR_SEQUENCE (expr) = get_insns (); |
---|
1337 | end_sequence (); |
---|
1338 | |
---|
1339 | second_try = expr; |
---|
1340 | |
---|
1341 | expr = make_node (RTL_EXPR); |
---|
1342 | TREE_TYPE (expr) = void_type_node; |
---|
1343 | RTL_EXPR_RTL (expr) = const0_rtx; |
---|
1344 | TREE_SIDE_EFFECTS (expr) = 1; |
---|
1345 | start_sequence_for_rtl_expr (expr); |
---|
1346 | |
---|
1347 | cont = gen_label_rtx (); |
---|
1348 | emit_move_insn (ret, gen_rtx (LABEL_REF, Pmode, cont)); |
---|
1349 | emit_jump (check); |
---|
1350 | emit_label (cont); |
---|
1351 | jumpif (make_tree (integer_type_node, flag), end); |
---|
1352 | start_protect (); |
---|
1353 | do_function_call (Unexpected, NULL_TREE, NULL_TREE); |
---|
1354 | assemble_external (TREE_OPERAND (Unexpected, 0)); |
---|
1355 | emit_barrier (); |
---|
1356 | end_protect (second_try); |
---|
1357 | |
---|
1358 | emit_label (check); |
---|
1359 | emit_move_insn (flag, const1_rtx); |
---|
1360 | cont = gen_label_rtx (); |
---|
1361 | while (raises) |
---|
1362 | { |
---|
1363 | tree exp; |
---|
1364 | tree match_type = TREE_VALUE (raises); |
---|
1365 | |
---|
1366 | if (match_type) |
---|
1367 | { |
---|
1368 | /* check TREE_VALUE (raises) here */ |
---|
1369 | exp = saved_throw_value; |
---|
1370 | exp = tree_cons (NULL_TREE, |
---|
1371 | build_eh_type_type (match_type), |
---|
1372 | tree_cons (NULL_TREE, |
---|
1373 | saved_throw_type, |
---|
1374 | tree_cons (NULL_TREE, exp, NULL_TREE))); |
---|
1375 | exp = build_function_call (CatchMatch, exp); |
---|
1376 | assemble_external (TREE_OPERAND (CatchMatch, 0)); |
---|
1377 | |
---|
1378 | jumpif (exp, cont); |
---|
1379 | } |
---|
1380 | |
---|
1381 | raises = TREE_CHAIN (raises); |
---|
1382 | } |
---|
1383 | emit_move_insn (flag, const0_rtx); |
---|
1384 | emit_label (cont); |
---|
1385 | emit_indirect_jump (ret); |
---|
1386 | emit_label (end); |
---|
1387 | |
---|
1388 | RTL_EXPR_SEQUENCE (expr) = get_insns (); |
---|
1389 | end_sequence (); |
---|
1390 | |
---|
1391 | end_protect (expr); |
---|
1392 | } |
---|
1393 | |
---|
1394 | /* This is called to expand all the toplevel exception handling |
---|
1395 | finalization for a function. It should only be called once per |
---|
1396 | function. */ |
---|
1397 | void |
---|
1398 | expand_exception_blocks () |
---|
1399 | { |
---|
1400 | static rtx funcend; |
---|
1401 | rtx insns; |
---|
1402 | |
---|
1403 | start_sequence (); |
---|
1404 | |
---|
1405 | funcend = gen_label_rtx (); |
---|
1406 | emit_jump (funcend); |
---|
1407 | /* expand_null_return (); */ |
---|
1408 | |
---|
1409 | start_sequence (); |
---|
1410 | |
---|
1411 | /* Add all the catch clauses here. */ |
---|
1412 | emit_insns (catch_clauses); |
---|
1413 | catch_clauses = NULL_RTX; |
---|
1414 | |
---|
1415 | expand_leftover_cleanups (); |
---|
1416 | |
---|
1417 | insns = get_insns (); |
---|
1418 | end_sequence (); |
---|
1419 | |
---|
1420 | /* Do this after we expand leftover cleanups, so that the end_protect |
---|
1421 | that expand_end_eh_spec does will match the right start_protect, |
---|
1422 | and make sure it comes out before the terminate protected region. */ |
---|
1423 | if (TYPE_RAISES_EXCEPTIONS (TREE_TYPE (current_function_decl))) |
---|
1424 | { |
---|
1425 | expand_end_eh_spec (TYPE_RAISES_EXCEPTIONS (TREE_TYPE (current_function_decl))); |
---|
1426 | push_to_sequence (insns); |
---|
1427 | |
---|
1428 | /* Now expand any new ones. */ |
---|
1429 | expand_leftover_cleanups (); |
---|
1430 | |
---|
1431 | insns = get_insns (); |
---|
1432 | end_sequence (); |
---|
1433 | } |
---|
1434 | |
---|
1435 | if (insns) |
---|
1436 | { |
---|
1437 | struct ehEntry entry; |
---|
1438 | |
---|
1439 | /* These are saved for the exception table. */ |
---|
1440 | push_rtl_perm (); |
---|
1441 | entry.start_label = gen_label_rtx (); |
---|
1442 | entry.end_label = gen_label_rtx (); |
---|
1443 | entry.exception_handler_label = gen_label_rtx (); |
---|
1444 | entry.finalization = TerminateFunctionCall; |
---|
1445 | entry.context = current_function_decl; |
---|
1446 | assemble_external (TREE_OPERAND (Terminate, 0)); |
---|
1447 | pop_rtl_from_perm (); |
---|
1448 | |
---|
1449 | LABEL_PRESERVE_P (entry.start_label) = 1; |
---|
1450 | LABEL_PRESERVE_P (entry.end_label) = 1; |
---|
1451 | LABEL_PRESERVE_P (entry.exception_handler_label) = 1; |
---|
1452 | |
---|
1453 | emit_label (entry.start_label); |
---|
1454 | emit_insns (insns); |
---|
1455 | |
---|
1456 | enqueue_eh_entry (&eh_table_output_queue, copy_eh_entry (&entry)); |
---|
1457 | |
---|
1458 | emit_label (entry.exception_handler_label); |
---|
1459 | expand_expr (entry.finalization, const0_rtx, VOIDmode, 0); |
---|
1460 | emit_label (entry.end_label); |
---|
1461 | emit_barrier (); |
---|
1462 | } |
---|
1463 | |
---|
1464 | { |
---|
1465 | /* Mark the end of the stack unwinder. */ |
---|
1466 | rtx unwind_insns; |
---|
1467 | start_sequence (); |
---|
1468 | end_eh_unwinder (funcend); |
---|
1469 | expand_leftover_cleanups (); |
---|
1470 | unwind_insns = get_insns (); |
---|
1471 | end_sequence (); |
---|
1472 | if (unwind_insns) |
---|
1473 | { |
---|
1474 | insns = unwind_insns; |
---|
1475 | emit_insns (insns); |
---|
1476 | } |
---|
1477 | } |
---|
1478 | |
---|
1479 | emit_label (funcend); |
---|
1480 | |
---|
1481 | /* Only if we had previous insns do we want to emit the jump around |
---|
1482 | them. If there weren't any, then insns will remain NULL_RTX. */ |
---|
1483 | if (insns) |
---|
1484 | insns = get_insns (); |
---|
1485 | end_sequence (); |
---|
1486 | |
---|
1487 | emit_insns (insns); |
---|
1488 | } |
---|
1489 | |
---|
1490 | |
---|
1491 | /* call this to expand a throw statement. This follows the following |
---|
1492 | algorithm: |
---|
1493 | |
---|
1494 | 1. Allocate space to save the current PC onto the stack. |
---|
1495 | 2. Generate and emit a label and save its address into the |
---|
1496 | newly allocated stack space since we can't save the pc directly. |
---|
1497 | 3. If this is the first call to throw in this function: |
---|
1498 | generate a label for the throw block |
---|
1499 | 4. jump to the throw block label. */ |
---|
1500 | void |
---|
1501 | expand_throw (exp) |
---|
1502 | tree exp; |
---|
1503 | { |
---|
1504 | rtx label; |
---|
1505 | |
---|
1506 | if (! doing_eh (1)) |
---|
1507 | return; |
---|
1508 | |
---|
1509 | /* This is the label that represents where in the code we were, when |
---|
1510 | we got an exception. This needs to be updated when we rethrow an |
---|
1511 | exception, so that the matching routine knows to search out. */ |
---|
1512 | label = gen_label_rtx (); |
---|
1513 | emit_label (label); |
---|
1514 | |
---|
1515 | if (exp) |
---|
1516 | { |
---|
1517 | tree throw_type; |
---|
1518 | tree e; |
---|
1519 | |
---|
1520 | /* throw expression */ |
---|
1521 | /* First, decay it. */ |
---|
1522 | exp = decay_conversion (exp); |
---|
1523 | |
---|
1524 | if (TREE_CODE (TREE_TYPE (exp)) == POINTER_TYPE) |
---|
1525 | { |
---|
1526 | throw_type = build_eh_type (exp); |
---|
1527 | exp = build_reinterpret_cast (ptr_type_node, exp); |
---|
1528 | } |
---|
1529 | else |
---|
1530 | { |
---|
1531 | /* Make a copy of the thrown object. WP 15.1.5 */ |
---|
1532 | exp = build_new (NULL_TREE, TREE_TYPE (exp), |
---|
1533 | build_tree_list (NULL_TREE, exp), |
---|
1534 | 0); |
---|
1535 | |
---|
1536 | if (exp == error_mark_node) |
---|
1537 | error (" in thrown expression"); |
---|
1538 | |
---|
1539 | throw_type = build_eh_type (build_indirect_ref (exp, NULL_PTR)); |
---|
1540 | } |
---|
1541 | |
---|
1542 | e = build_modify_expr (saved_throw_type, NOP_EXPR, throw_type); |
---|
1543 | expand_expr (e, const0_rtx, VOIDmode, 0); |
---|
1544 | e = build_modify_expr (saved_throw_value, NOP_EXPR, exp); |
---|
1545 | e = build1 (CLEANUP_POINT_EXPR, TREE_TYPE (e), e); |
---|
1546 | expand_expr (e, const0_rtx, VOIDmode, 0); |
---|
1547 | } |
---|
1548 | else |
---|
1549 | { |
---|
1550 | /* rethrow current exception */ |
---|
1551 | /* This part is easy, as we don't have to do anything else. */ |
---|
1552 | } |
---|
1553 | |
---|
1554 | expand_internal_throw (gen_rtx (LABEL_REF, Pmode, label)); |
---|
1555 | } |
---|
1556 | |
---|
1557 | void |
---|
1558 | end_protect_partials () { |
---|
1559 | while (protect_list) |
---|
1560 | { |
---|
1561 | end_protect (TREE_VALUE (protect_list)); |
---|
1562 | protect_list = TREE_CHAIN (protect_list); |
---|
1563 | } |
---|
1564 | } |
---|
1565 | |
---|
1566 | int |
---|
1567 | might_have_exceptions_p () |
---|
1568 | { |
---|
1569 | if (eh_table_output_queue.head) |
---|
1570 | return 1; |
---|
1571 | return 0; |
---|
1572 | } |
---|
1573 | |
---|
1574 | /* Output the exception table. |
---|
1575 | Return the number of handlers. */ |
---|
1576 | void |
---|
1577 | emit_exception_table () |
---|
1578 | { |
---|
1579 | int count = 0; |
---|
1580 | extern FILE *asm_out_file; |
---|
1581 | struct ehEntry *entry; |
---|
1582 | tree eh_node_decl; |
---|
1583 | |
---|
1584 | if (! doing_eh (0)) |
---|
1585 | return; |
---|
1586 | |
---|
1587 | exception_section (); |
---|
1588 | |
---|
1589 | /* Beginning marker for table. */ |
---|
1590 | assemble_align (GET_MODE_ALIGNMENT (Pmode)); |
---|
1591 | assemble_label ("__EXCEPTION_TABLE__"); |
---|
1592 | output_exception_table_entry (asm_out_file, |
---|
1593 | const0_rtx, const0_rtx, const0_rtx); |
---|
1594 | |
---|
1595 | while (entry = dequeue_eh_entry (&eh_table_output_queue)) |
---|
1596 | { |
---|
1597 | tree context = entry->context; |
---|
1598 | |
---|
1599 | if (context && ! TREE_ASM_WRITTEN (context)) |
---|
1600 | continue; |
---|
1601 | |
---|
1602 | count++; |
---|
1603 | output_exception_table_entry (asm_out_file, |
---|
1604 | entry->start_label, entry->end_label, |
---|
1605 | entry->exception_handler_label); |
---|
1606 | } |
---|
1607 | |
---|
1608 | /* Ending marker for table. */ |
---|
1609 | assemble_label ("__EXCEPTION_END__"); |
---|
1610 | output_exception_table_entry (asm_out_file, |
---|
1611 | constm1_rtx, constm1_rtx, constm1_rtx); |
---|
1612 | } |
---|
1613 | |
---|
1614 | void |
---|
1615 | register_exception_table () |
---|
1616 | { |
---|
1617 | emit_library_call (gen_rtx (SYMBOL_REF, Pmode, "__register_exceptions"), 0, |
---|
1618 | VOIDmode, 1, |
---|
1619 | gen_rtx (SYMBOL_REF, Pmode, "__EXCEPTION_TABLE__"), |
---|
1620 | Pmode); |
---|
1621 | } |
---|
1622 | |
---|
1623 | /* Build a throw expression. */ |
---|
1624 | tree |
---|
1625 | build_throw (e) |
---|
1626 | tree e; |
---|
1627 | { |
---|
1628 | if (e != error_mark_node) |
---|
1629 | { |
---|
1630 | e = build1 (THROW_EXPR, void_type_node, e); |
---|
1631 | TREE_SIDE_EFFECTS (e) = 1; |
---|
1632 | TREE_USED (e) = 1; |
---|
1633 | } |
---|
1634 | return e; |
---|
1635 | } |
---|
1636 | |
---|
1637 | start_eh_unwinder () |
---|
1638 | { |
---|
1639 | start_protect (); |
---|
1640 | } |
---|
1641 | |
---|
1642 | end_eh_unwinder (end) |
---|
1643 | rtx end; |
---|
1644 | { |
---|
1645 | tree expr; |
---|
1646 | rtx return_val_rtx, ret_val, label; |
---|
1647 | |
---|
1648 | if (! doing_eh (0)) |
---|
1649 | return; |
---|
1650 | |
---|
1651 | expr = make_node (RTL_EXPR); |
---|
1652 | TREE_TYPE (expr) = void_type_node; |
---|
1653 | RTL_EXPR_RTL (expr) = const0_rtx; |
---|
1654 | TREE_SIDE_EFFECTS (expr) = 1; |
---|
1655 | start_sequence_for_rtl_expr (expr); |
---|
1656 | |
---|
1657 | ret_val = expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS, |
---|
1658 | 0, hard_frame_pointer_rtx); |
---|
1659 | return_val_rtx = copy_to_reg (ret_val); |
---|
1660 | #ifdef NORMAL_RETURN_ADDR_OFFSET |
---|
1661 | return_val_rtx = plus_constant (return_val_rtx, NORMAL_RETURN_ADDR_OFFSET-1); |
---|
1662 | #else |
---|
1663 | return_val_rtx = plus_constant (return_val_rtx, -1); |
---|
1664 | #endif |
---|
1665 | emit_move_insn (DECL_RTL (saved_pc), return_val_rtx); |
---|
1666 | |
---|
1667 | #ifdef JUMP_TO_THROW |
---|
1668 | emit_move_insn (ret_val, gen_rtx (SYMBOL_REF, Pmode, "__throw")); |
---|
1669 | #else |
---|
1670 | label = gen_label_rtx (); |
---|
1671 | emit_move_insn (ret_val, gen_rtx (LABEL_REF, Pmode, label)); |
---|
1672 | #endif |
---|
1673 | |
---|
1674 | #ifdef NORMAL_RETURN_ADDR_OFFSET |
---|
1675 | return_val_rtx = plus_constant (ret_val, -NORMAL_RETURN_ADDR_OFFSET); |
---|
1676 | if (return_val_rtx != ret_val) |
---|
1677 | emit_move_insn (ret_val, return_val_rtx); |
---|
1678 | #endif |
---|
1679 | |
---|
1680 | emit_jump (end); |
---|
1681 | |
---|
1682 | #ifndef JUMP_TO_THROW |
---|
1683 | emit_label (label); |
---|
1684 | do_function_call (Throw, NULL_TREE, NULL_TREE); |
---|
1685 | #endif |
---|
1686 | |
---|
1687 | RTL_EXPR_SEQUENCE (expr) = get_insns (); |
---|
1688 | end_sequence (); |
---|
1689 | end_protect (expr); |
---|
1690 | } |
---|