The Android Open Source Project | 593c365 | 2008-10-21 07:00:00 -0700 | [diff] [blame] | 1 | /* Return location expression list. |
| 2 | Copyright (C) 2000, 2001, 2002, 2004 Red Hat, Inc. |
| 3 | Written by Ulrich Drepper <drepper@redhat.com>, 2000. |
| 4 | |
| 5 | This program is Open Source software; you can redistribute it and/or |
| 6 | modify it under the terms of the Open Software License version 1.0 as |
| 7 | published by the Open Source Initiative. |
| 8 | |
| 9 | You should have received a copy of the Open Software License along |
| 10 | with this program; if not, you may obtain a copy of the Open Software |
| 11 | License version 1.0 from http://www.opensource.org/licenses/osl.php or |
| 12 | by writing the Open Source Initiative c/o Lawrence Rosen, Esq., |
| 13 | 3001 King Ranch Road, Ukiah, CA 95482. */ |
| 14 | |
| 15 | #ifdef HAVE_CONFIG_H |
| 16 | # include <config.h> |
| 17 | #endif |
| 18 | |
| 19 | #include <dwarf.h> |
| 20 | #include <search.h> |
| 21 | #include <stdlib.h> |
| 22 | |
| 23 | #include <libdwP.h> |
| 24 | |
| 25 | |
| 26 | struct loclist |
| 27 | { |
| 28 | uint8_t atom; |
| 29 | Dwarf_Word number; |
| 30 | Dwarf_Word number2; |
| 31 | Dwarf_Word offset; |
| 32 | struct loclist *next; |
| 33 | }; |
| 34 | |
| 35 | |
| 36 | static int |
| 37 | loc_compare (const void *p1, const void *p2) |
| 38 | { |
| 39 | const struct loc_s *l1 = (const struct loc_s *) p1; |
| 40 | const struct loc_s *l2 = (const struct loc_s *) p2; |
| 41 | |
| 42 | if ((uintptr_t) l1->addr < (uintptr_t) l2->addr) |
| 43 | return -1; |
| 44 | if ((uintptr_t) l1->addr > (uintptr_t) l2->addr) |
| 45 | return 1; |
| 46 | |
| 47 | return 0; |
| 48 | } |
| 49 | |
| 50 | |
| 51 | int |
| 52 | dwarf_getloclist (attr, llbuf, listlen) |
| 53 | Dwarf_Attribute *attr; |
| 54 | Dwarf_Loc **llbuf; |
| 55 | size_t *listlen; |
| 56 | { |
| 57 | /* Must by one of the attribute listed below. */ |
| 58 | if (attr->code != DW_AT_location |
| 59 | && attr->code != DW_AT_data_member_location |
| 60 | && attr->code != DW_AT_vtable_elem_location |
| 61 | && attr->code != DW_AT_string_length |
| 62 | && attr->code != DW_AT_use_location |
| 63 | && attr->code != DW_AT_return_addr) |
| 64 | { |
| 65 | __libdw_seterrno (DWARF_E_NO_LOCLIST); |
| 66 | return -1; |
| 67 | } |
| 68 | |
| 69 | struct Dwarf_CU *cu = attr->cu; |
| 70 | Dwarf *dbg = cu->dbg; |
| 71 | |
| 72 | /* Must have the form data4 or data8 which act as an offset. */ |
| 73 | Dwarf_Block block; |
| 74 | if (dwarf_formblock (attr, &block) != 0) |
| 75 | return -1; |
| 76 | |
| 77 | /* Check whether we already looked at this list. */ |
| 78 | struct loc_s fake = { .addr = block.data }; |
| 79 | struct loc_s **found = tfind (&fake, &cu->locs, loc_compare); |
| 80 | if (found != NULL) |
| 81 | { |
| 82 | /* We already saw it. */ |
| 83 | *llbuf = (*found)->loc; |
| 84 | *listlen = (*found)->nloc; |
| 85 | |
| 86 | return 0; |
| 87 | } |
| 88 | |
| 89 | unsigned char *data = block.data; |
| 90 | unsigned char *const end_data = data + block.length; |
| 91 | |
| 92 | struct loclist *loclist = NULL; |
| 93 | unsigned int n = 0; |
| 94 | /* Decode the opcodes. It is possible in some situations to have a |
| 95 | block of size zero. */ |
| 96 | while (data < end_data) |
| 97 | { |
| 98 | struct loclist *newloc; |
| 99 | newloc = (struct loclist *) alloca (sizeof (struct loclist)); |
| 100 | newloc->number = 0; |
| 101 | newloc->number2 = 0; |
| 102 | newloc->offset = data - block.data; |
| 103 | newloc->next = loclist; |
| 104 | loclist = newloc; |
| 105 | ++n; |
| 106 | |
| 107 | switch ((newloc->atom = *data++)) |
| 108 | { |
| 109 | case DW_OP_addr: |
| 110 | /* Address, depends on address size of CU. */ |
| 111 | if (cu->address_size == 4) |
| 112 | { |
| 113 | if (unlikely (data + 4 > end_data)) |
| 114 | { |
| 115 | invalid: |
| 116 | __libdw_seterrno (DWARF_E_INVALID_DWARF); |
| 117 | return -1; |
| 118 | } |
| 119 | |
| 120 | newloc->number = read_4ubyte_unaligned_inc (dbg, data); |
| 121 | } |
| 122 | else |
| 123 | { |
| 124 | if (unlikely (data + 8 > end_data)) |
| 125 | goto invalid; |
| 126 | |
| 127 | newloc->number = read_8ubyte_unaligned_inc (dbg, data); |
| 128 | } |
| 129 | break; |
| 130 | |
| 131 | case DW_OP_deref: |
| 132 | case DW_OP_dup: |
| 133 | case DW_OP_drop: |
| 134 | case DW_OP_over: |
| 135 | case DW_OP_swap: |
| 136 | case DW_OP_rot: |
| 137 | case DW_OP_xderef: |
| 138 | case DW_OP_abs: |
| 139 | case DW_OP_and: |
| 140 | case DW_OP_div: |
| 141 | case DW_OP_minus: |
| 142 | case DW_OP_mod: |
| 143 | case DW_OP_mul: |
| 144 | case DW_OP_neg: |
| 145 | case DW_OP_not: |
| 146 | case DW_OP_or: |
| 147 | case DW_OP_plus: |
| 148 | case DW_OP_shl: |
| 149 | case DW_OP_shr: |
| 150 | case DW_OP_shra: |
| 151 | case DW_OP_xor: |
| 152 | case DW_OP_eq: |
| 153 | case DW_OP_ge: |
| 154 | case DW_OP_gt: |
| 155 | case DW_OP_le: |
| 156 | case DW_OP_lt: |
| 157 | case DW_OP_ne: |
| 158 | case DW_OP_lit0 ... DW_OP_lit31: |
| 159 | case DW_OP_reg0 ... DW_OP_reg31: |
| 160 | case DW_OP_nop: |
| 161 | case DW_OP_push_object_address: |
| 162 | case DW_OP_call_ref: |
| 163 | /* No operand. */ |
| 164 | break; |
| 165 | |
| 166 | case DW_OP_const1u: |
| 167 | case DW_OP_pick: |
| 168 | case DW_OP_deref_size: |
| 169 | case DW_OP_xderef_size: |
| 170 | if (unlikely (data >= end_data)) |
| 171 | goto invalid; |
| 172 | |
| 173 | newloc->number = *data++; |
| 174 | break; |
| 175 | |
| 176 | case DW_OP_const1s: |
| 177 | if (unlikely (data >= end_data)) |
| 178 | goto invalid; |
| 179 | |
| 180 | newloc->number = *((int8_t *) data); |
| 181 | ++data; |
| 182 | break; |
| 183 | |
| 184 | case DW_OP_const2u: |
| 185 | if (unlikely (data + 2 > end_data)) |
| 186 | goto invalid; |
| 187 | |
| 188 | newloc->number = read_2ubyte_unaligned_inc (dbg, data); |
| 189 | break; |
| 190 | |
| 191 | case DW_OP_const2s: |
| 192 | case DW_OP_skip: |
| 193 | case DW_OP_bra: |
| 194 | case DW_OP_call2: |
| 195 | if (unlikely (data + 2 > end_data)) |
| 196 | goto invalid; |
| 197 | |
| 198 | newloc->number = read_2sbyte_unaligned_inc (dbg, data); |
| 199 | break; |
| 200 | |
| 201 | case DW_OP_const4u: |
| 202 | if (unlikely (data + 4 > end_data)) |
| 203 | goto invalid; |
| 204 | |
| 205 | newloc->number = read_4ubyte_unaligned_inc (dbg, data); |
| 206 | break; |
| 207 | |
| 208 | case DW_OP_const4s: |
| 209 | case DW_OP_call4: |
| 210 | if (unlikely (data + 4 > end_data)) |
| 211 | goto invalid; |
| 212 | |
| 213 | newloc->number = read_4sbyte_unaligned_inc (dbg, data); |
| 214 | break; |
| 215 | |
| 216 | case DW_OP_const8u: |
| 217 | if (unlikely (data + 8 > end_data)) |
| 218 | goto invalid; |
| 219 | |
| 220 | newloc->number = read_8ubyte_unaligned_inc (dbg, data); |
| 221 | break; |
| 222 | |
| 223 | case DW_OP_const8s: |
| 224 | if (unlikely (data + 8 > end_data)) |
| 225 | goto invalid; |
| 226 | |
| 227 | newloc->number = read_8sbyte_unaligned_inc (dbg, data); |
| 228 | break; |
| 229 | |
| 230 | case DW_OP_constu: |
| 231 | case DW_OP_plus_uconst: |
| 232 | case DW_OP_regx: |
| 233 | case DW_OP_piece: |
| 234 | /* XXX Check size. */ |
| 235 | get_uleb128 (newloc->number, data); |
| 236 | break; |
| 237 | |
| 238 | case DW_OP_consts: |
| 239 | case DW_OP_breg0 ... DW_OP_breg31: |
| 240 | case DW_OP_fbreg: |
| 241 | /* XXX Check size. */ |
| 242 | get_sleb128 (newloc->number, data); |
| 243 | break; |
| 244 | |
| 245 | case DW_OP_bregx: |
| 246 | /* XXX Check size. */ |
| 247 | get_uleb128 (newloc->number, data); |
| 248 | get_sleb128 (newloc->number2, data); |
| 249 | break; |
| 250 | |
| 251 | default: |
| 252 | goto invalid; |
| 253 | } |
| 254 | } |
| 255 | |
| 256 | if (unlikely (n == 0)) |
| 257 | { |
| 258 | /* This is not allowed. |
| 259 | |
| 260 | XXX Is it? */ |
| 261 | goto invalid; |
| 262 | } |
| 263 | |
| 264 | /* Allocate the array. */ |
| 265 | Dwarf_Loc *result = libdw_alloc (dbg, Dwarf_Loc, sizeof (Dwarf_Loc), n); |
| 266 | |
| 267 | /* Store the result. */ |
| 268 | *llbuf = result; |
| 269 | *listlen = n; |
| 270 | |
| 271 | do |
| 272 | { |
| 273 | /* We populate the array from the back since the list is |
| 274 | backwards. */ |
| 275 | --n; |
| 276 | result[n].atom = loclist->atom; |
| 277 | result[n].number = loclist->number; |
| 278 | result[n].number2 = loclist->number2; |
| 279 | result[n].offset = loclist->offset; |
| 280 | |
| 281 | loclist = loclist->next; |
| 282 | } |
| 283 | while (n > 0); |
| 284 | |
| 285 | /* Insert a record in the search tree so that we can find it again |
| 286 | later. */ |
| 287 | struct loc_s *newp = libdw_alloc (dbg, struct loc_s, sizeof (struct loc_s), |
| 288 | 1); |
| 289 | newp->addr = block.data; |
| 290 | newp->loc = result; |
| 291 | newp->nloc = *listlen; |
| 292 | (void) tsearch (newp, &cu->locs, loc_compare); |
| 293 | |
| 294 | /* We did it. */ |
| 295 | return 0; |
| 296 | } |