| 1 | /* Address ranges. |
| 2 | Copyright (C) 1998-2018 Free Software Foundation, Inc. |
| 3 | Contributed by Cygnus Solutions. |
| 4 | |
| 5 | This file is part of the GNU Simulators. |
| 6 | |
| 7 | This program is free software; you can redistribute it and/or modify |
| 8 | it under the terms of the GNU General Public License as published by |
| 9 | the Free Software Foundation; either version 3 of the License, or |
| 10 | (at your option) any later version. |
| 11 | |
| 12 | This program is distributed in the hope that it will be useful, |
| 13 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 15 | GNU General Public License for more details. |
| 16 | |
| 17 | You should have received a copy of the GNU General Public License |
| 18 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
| 19 | |
| 20 | /* Tell sim-arange.h it's us. */ |
| 21 | #define SIM_ARANGE_C |
| 22 | |
| 23 | #include "libiberty.h" |
| 24 | #include "sim-basics.h" |
| 25 | #include "sim-assert.h" |
| 26 | |
| 27 | #ifdef HAVE_STDLIB_H |
| 28 | #include <stdlib.h> |
| 29 | #endif |
| 30 | |
| 31 | #ifdef HAVE_STRING_H |
| 32 | #include <string.h> |
| 33 | #endif |
| 34 | |
| 35 | #define DEFINE_INLINE_P (! defined (SIM_ARANGE_C_INCLUDED)) |
| 36 | #define DEFINE_NON_INLINE_P defined (SIM_ARANGE_C_INCLUDED) |
| 37 | |
| 38 | #if DEFINE_NON_INLINE_P |
| 39 | |
| 40 | /* Insert a range. */ |
| 41 | |
| 42 | static void |
| 43 | insert_range (ADDR_SUBRANGE **pos, ADDR_SUBRANGE *asr) |
| 44 | { |
| 45 | asr->next = *pos; |
| 46 | *pos = asr; |
| 47 | } |
| 48 | |
| 49 | /* Delete a range. */ |
| 50 | |
| 51 | static void |
| 52 | delete_range (ADDR_SUBRANGE **thisasrp) |
| 53 | { |
| 54 | ADDR_SUBRANGE *thisasr; |
| 55 | |
| 56 | thisasr = *thisasrp; |
| 57 | *thisasrp = thisasr->next; |
| 58 | |
| 59 | free (thisasr); |
| 60 | } |
| 61 | |
| 62 | /* Add or delete an address range. |
| 63 | This code was borrowed from linux's locks.c:posix_lock_file(). |
| 64 | ??? Todo: Given our simpler needs this could be simplified |
| 65 | (split into two fns). */ |
| 66 | |
| 67 | static void |
| 68 | frob_range (ADDR_RANGE *ar, address_word start, address_word end, int delete_p) |
| 69 | { |
| 70 | ADDR_SUBRANGE *asr; |
| 71 | ADDR_SUBRANGE *new_asr, *new_asr2; |
| 72 | ADDR_SUBRANGE *left = NULL; |
| 73 | ADDR_SUBRANGE *right = NULL; |
| 74 | ADDR_SUBRANGE **before; |
| 75 | ADDR_SUBRANGE init_caller; |
| 76 | ADDR_SUBRANGE *caller = &init_caller; |
| 77 | int added_p = 0; |
| 78 | |
| 79 | memset (caller, 0, sizeof (ADDR_SUBRANGE)); |
| 80 | new_asr = ZALLOC (ADDR_SUBRANGE); |
| 81 | new_asr2 = ZALLOC (ADDR_SUBRANGE); |
| 82 | |
| 83 | caller->start = start; |
| 84 | caller->end = end; |
| 85 | before = &ar->ranges; |
| 86 | |
| 87 | while ((asr = *before) != NULL) |
| 88 | { |
| 89 | if (! delete_p) |
| 90 | { |
| 91 | /* Try next range if current range preceeds new one and not |
| 92 | adjacent or overlapping. */ |
| 93 | if (asr->end < caller->start - 1) |
| 94 | goto next_range; |
| 95 | |
| 96 | /* Break out if new range preceeds current one and not |
| 97 | adjacent or overlapping. */ |
| 98 | if (asr->start > caller->end + 1) |
| 99 | break; |
| 100 | |
| 101 | /* If we come here, the new and current ranges are adjacent or |
| 102 | overlapping. Make one range yielding from the lower start address |
| 103 | of both ranges to the higher end address. */ |
| 104 | if (asr->start > caller->start) |
| 105 | asr->start = caller->start; |
| 106 | else |
| 107 | caller->start = asr->start; |
| 108 | if (asr->end < caller->end) |
| 109 | asr->end = caller->end; |
| 110 | else |
| 111 | caller->end = asr->end; |
| 112 | |
| 113 | if (added_p) |
| 114 | { |
| 115 | delete_range (before); |
| 116 | continue; |
| 117 | } |
| 118 | caller = asr; |
| 119 | added_p = 1; |
| 120 | } |
| 121 | else /* deleting a range */ |
| 122 | { |
| 123 | /* Try next range if current range preceeds new one. */ |
| 124 | if (asr->end < caller->start) |
| 125 | goto next_range; |
| 126 | |
| 127 | /* Break out if new range preceeds current one. */ |
| 128 | if (asr->start > caller->end) |
| 129 | break; |
| 130 | |
| 131 | added_p = 1; |
| 132 | |
| 133 | if (asr->start < caller->start) |
| 134 | left = asr; |
| 135 | |
| 136 | /* If the next range in the list has a higher end |
| 137 | address than the new one, insert the new one here. */ |
| 138 | if (asr->end > caller->end) |
| 139 | { |
| 140 | right = asr; |
| 141 | break; |
| 142 | } |
| 143 | if (asr->start >= caller->start) |
| 144 | { |
| 145 | /* The new range completely replaces an old |
| 146 | one (This may happen several times). */ |
| 147 | if (added_p) |
| 148 | { |
| 149 | delete_range (before); |
| 150 | continue; |
| 151 | } |
| 152 | |
| 153 | /* Replace the old range with the new one. */ |
| 154 | asr->start = caller->start; |
| 155 | asr->end = caller->end; |
| 156 | caller = asr; |
| 157 | added_p = 1; |
| 158 | } |
| 159 | } |
| 160 | |
| 161 | /* Go on to next range. */ |
| 162 | next_range: |
| 163 | before = &asr->next; |
| 164 | } |
| 165 | |
| 166 | if (!added_p) |
| 167 | { |
| 168 | if (delete_p) |
| 169 | goto out; |
| 170 | new_asr->start = caller->start; |
| 171 | new_asr->end = caller->end; |
| 172 | insert_range (before, new_asr); |
| 173 | new_asr = NULL; |
| 174 | } |
| 175 | if (right) |
| 176 | { |
| 177 | if (left == right) |
| 178 | { |
| 179 | /* The new range breaks the old one in two pieces, |
| 180 | so we have to use the second new range. */ |
| 181 | new_asr2->start = right->start; |
| 182 | new_asr2->end = right->end; |
| 183 | left = new_asr2; |
| 184 | insert_range (before, left); |
| 185 | new_asr2 = NULL; |
| 186 | } |
| 187 | right->start = caller->end + 1; |
| 188 | } |
| 189 | if (left) |
| 190 | { |
| 191 | left->end = caller->start - 1; |
| 192 | } |
| 193 | |
| 194 | out: |
| 195 | if (new_asr) |
| 196 | free (new_asr); |
| 197 | if (new_asr2) |
| 198 | free (new_asr2); |
| 199 | } |
| 200 | |
| 201 | /* Free T and all subtrees. */ |
| 202 | |
| 203 | static void |
| 204 | free_search_tree (ADDR_RANGE_TREE *t) |
| 205 | { |
| 206 | if (t != NULL) |
| 207 | { |
| 208 | free_search_tree (t->lower); |
| 209 | free_search_tree (t->higher); |
| 210 | free (t); |
| 211 | } |
| 212 | } |
| 213 | |
| 214 | /* Subroutine of build_search_tree to recursively build a balanced tree. |
| 215 | ??? It's not an optimum tree though. */ |
| 216 | |
| 217 | static ADDR_RANGE_TREE * |
| 218 | build_tree_1 (ADDR_SUBRANGE **asrtab, unsigned int n) |
| 219 | { |
| 220 | unsigned int mid = n / 2; |
| 221 | ADDR_RANGE_TREE *t; |
| 222 | |
| 223 | if (n == 0) |
| 224 | return NULL; |
| 225 | t = (ADDR_RANGE_TREE *) xmalloc (sizeof (ADDR_RANGE_TREE)); |
| 226 | t->start = asrtab[mid]->start; |
| 227 | t->end = asrtab[mid]->end; |
| 228 | if (mid != 0) |
| 229 | t->lower = build_tree_1 (asrtab, mid); |
| 230 | else |
| 231 | t->lower = NULL; |
| 232 | if (n > mid + 1) |
| 233 | t->higher = build_tree_1 (asrtab + mid + 1, n - mid - 1); |
| 234 | else |
| 235 | t->higher = NULL; |
| 236 | return t; |
| 237 | } |
| 238 | |
| 239 | /* Build a search tree for address range AR. */ |
| 240 | |
| 241 | static void |
| 242 | build_search_tree (ADDR_RANGE *ar) |
| 243 | { |
| 244 | /* ??? Simple version for now. */ |
| 245 | ADDR_SUBRANGE *asr,**asrtab; |
| 246 | unsigned int i, n; |
| 247 | |
| 248 | for (n = 0, asr = ar->ranges; asr != NULL; ++n, asr = asr->next) |
| 249 | continue; |
| 250 | asrtab = (ADDR_SUBRANGE **) xmalloc (n * sizeof (ADDR_SUBRANGE *)); |
| 251 | for (i = 0, asr = ar->ranges; i < n; ++i, asr = asr->next) |
| 252 | asrtab[i] = asr; |
| 253 | ar->range_tree = build_tree_1 (asrtab, n); |
| 254 | free (asrtab); |
| 255 | } |
| 256 | |
| 257 | void |
| 258 | sim_addr_range_add (ADDR_RANGE *ar, address_word start, address_word end) |
| 259 | { |
| 260 | frob_range (ar, start, end, 0); |
| 261 | |
| 262 | /* Rebuild the search tree. */ |
| 263 | /* ??? Instead of rebuilding it here it could be done in a module resume |
| 264 | handler, say by first checking for a `changed' flag, assuming of course |
| 265 | this would never be done while the simulation is running. */ |
| 266 | free_search_tree (ar->range_tree); |
| 267 | build_search_tree (ar); |
| 268 | } |
| 269 | |
| 270 | void |
| 271 | sim_addr_range_delete (ADDR_RANGE *ar, address_word start, address_word end) |
| 272 | { |
| 273 | frob_range (ar, start, end, 1); |
| 274 | |
| 275 | /* Rebuild the search tree. */ |
| 276 | /* ??? Instead of rebuilding it here it could be done in a module resume |
| 277 | handler, say by first checking for a `changed' flag, assuming of course |
| 278 | this would never be done while the simulation is running. */ |
| 279 | free_search_tree (ar->range_tree); |
| 280 | build_search_tree (ar); |
| 281 | } |
| 282 | |
| 283 | #endif /* DEFINE_NON_INLINE_P */ |
| 284 | |
| 285 | #if DEFINE_INLINE_P |
| 286 | |
| 287 | SIM_ARANGE_INLINE int |
| 288 | sim_addr_range_hit_p (ADDR_RANGE *ar, address_word addr) |
| 289 | { |
| 290 | ADDR_RANGE_TREE *t = ar->range_tree; |
| 291 | |
| 292 | while (t != NULL) |
| 293 | { |
| 294 | if (addr < t->start) |
| 295 | t = t->lower; |
| 296 | else if (addr > t->end) |
| 297 | t = t->higher; |
| 298 | else |
| 299 | return 1; |
| 300 | } |
| 301 | return 0; |
| 302 | } |
| 303 | |
| 304 | #endif /* DEFINE_INLINE_P */ |