src/vm/jit/arm/patcher.c

   1 /* src/vm/jit/arm/patcher.c - ARM code patching functions
   2
   3    Copyright (C) 1996-2005, 2006, 2007, 2008
   4    CACAOVM - Verein zur Foerderung der freien virtuellen Maschine CACAO
   5    Copyright (C) 2008 Theobroma Systems Ltd.
   6
   7    This file is part of CACAO.
   8
   9    This program is free software; you can redistribute it and/or
  10    modify it under the terms of the GNU General Public License as
  11    published by the Free Software Foundation; either version 2, or (at
  12    your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful, but
  15    WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17    General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program; if not, write to the Free Software
  21    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  22    02110-1301, USA.
  23
  24 */
  25
  26
  27 #include "config.h"
  28
  29 #include <assert.h>
  30 #include <stdint.h>
  31
  32 #include "vm/types.h"
  33
  34 #include "vm/jit/arm/md.h"
  35
  36 #include "mm/memory.hpp"
  37
  38 #include "native/native.hpp"
  39
  40 #include "vm/jit/builtin.hpp"
  41 #include "vm/class.hpp"
  42 #include "vm/field.hpp"
  43 #include "vm/initialize.hpp"
  44 #include "vm/options.h"
  45 #include "vm/references.h"
  46 #include "vm/resolve.hpp"
  47
  48 #include "vm/jit/asmpart.h"
  49 #include "vm/jit/patcher-common.hpp"
  50
  51
  52 #define gen_resolveload(inst,offset) \
  53         assert((offset) >= -0x0fff && (offset) <= 0x0fff); \
  54         assert(!((inst) & 0x0fff)); \
  55         if ((offset) <  0) { \
  56                 (inst) = ((inst) & 0xff7ff000) | ((-(offset)) & 0x0fff); \
  57                 /*(inst) &= ~(1 << 23);*/ \
  58         } else { \
  59                 (inst) = ((inst) & 0xfffff000) | ((offset) & 0x0fff); \
  60                 /*(inst) |= (1 << 23);*/ \
  61         }
  62
  63
  64 /* patcher_patch_code **********************************************************
  65
  66    Just patches back the original machine code.
  67
  68 *******************************************************************************/
  69
  70 void patcher_patch_code(patchref_t *pr)
  71 {
  72     *((uint32_t*) pr->mpc) = (uint32_t) pr->mcode;
  73     md_icacheflush((void*) pr->mpc, 1 * 4);
  74 }
  75
  76
  77 /**
  78  * Check if the trap instruction at the given PC is valid.
  79  *
  80  * @param pc Program counter.
  81  *
  82  * @return true if valid, false otherwise.
  83  */
  84 bool patcher_is_valid_trap_instruction_at(void* pc)
  85 {
  86         uint32_t mcode = *((uint32_t*) pc);
  87
  88         // Check for the undefined instruction we use.
  89         if ((mcode & 0x0ff000f0) != 0x07f000f0) {
  90                 return false;
  91         }
  92
  93         return true;
  94 }
  95
  96
  97 /* patcher_get_putstatic *******************************************************
  98
  99    Machine code:
 100
 101    <patched call position>
 102    e51c103c    ldr   r1, [ip, #-60]
 103
 104 *******************************************************************************/
 105
 106 bool patcher_get_putstatic(patchref_t *pr)
 107 {
 108         unresolved_field* uf    = (unresolved_field *) pr->ref;
 109         uintptr_t*        datap = (uintptr_t*)         pr->datap;
 110
 111         // Resolve the field.
 112         fieldinfo* fi = resolve_field_eager(uf);
 113
 114         if (fi == NULL)
 115                 return false;
 116
 117         // Check if the field's class is initialized.
 118         if (!(fi->clazz->state & CLASS_INITIALIZED))
 119                 if (!initialize_class(fi->clazz))
 120                         return false;
 121
 122         // Patch the field value's address.
 123         *datap = (uintptr_t) fi->value;
 124
 125         // Patch back the original code.
 126         patcher_patch_code(pr);
 127
 128         return true;
 129 }
 130
 131
 132 /* patcher_get_putfield ********************************************************
 133
 134    Machine code:
 135
 136    <patched call position>
 137    e58a8000    str   r8, [sl, #__]
 138
 139 *******************************************************************************/
 140
 141 bool patcher_get_putfield(patchref_t *pr)
 142 {
 143         uint32_t*         pc = (uint32_t*)         pr->mpc;
 144         unresolved_field* uf = (unresolved_field*) pr->ref;
 145
 146         // Resolve the field.
 147         fieldinfo* fi = resolve_field_eager(uf);
 148
 149         if (fi == NULL)
 150                 return false;
 151
 152         // Patch the field's offset into the instruction.
 153
 154         switch(fi->type) {
 155         case TYPE_ADR:
 156         case TYPE_INT:
 157 #if defined(ENABLE_SOFTFLOAT)
 158         case TYPE_FLT:
 159 #endif
 160                 assert(fi->offset <= 0x0fff);
 161                 pr->mcode |= (fi->offset & 0x0fff);
 162                 break;
 163
 164         case TYPE_LNG:
 165 #if defined(ENABLE_SOFTFLOAT)
 166         case TYPE_DBL:
 167 #endif
 168                 assert((fi->offset + 4) <= 0x0fff);
 169                 pr->mcode |= ((fi->offset + 0) & 0x0fff);
 170                 pc[1] &= 0xfffff000;
 171                 pc[1] |= ((fi->offset + 4) & 0x0fff);
 172                 break;
 173
 174 #if !defined(ENABLE_SOFTFLOAT)
 175         case TYPE_FLT:
 176         case TYPE_DBL:
 177                 assert(fi->offset <= 0x03ff);
 178                 pr->mcode |= ((fi->offset >> 2) & 0x00ff);
 179                 break;
 180 #endif
 181         }
 182
 183         // Synchronize instruction cache.
 184         md_icacheflush(pc, 2 * 4);
 185
 186         // Patch back the original code.
 187         patcher_patch_code(pr);
 188
 189         return true;
 190 }
 191
 192
 193 /* patcher_resolve_classref_to_classinfo ***************************************
 194
 195    ACONST - Machine code:
 196
 197    <patched call postition>
 198    e51cc030    ldr   r0, [ip, #-48]
 199
 200    MULTIANEWARRAY - Machine code:
 201
 202    <patched call position>
 203    e3a00002    mov   r0, #2  ; 0x2
 204    e51c1064    ldr   r1, [ip, #-100]
 205    e1a0200d    mov   r2, sp
 206    e1a0e00f    mov   lr, pc
 207    e51cf068    ldr   pc, [ip, #-104]
 208
 209    ARRAYCHECKCAST - Machine code:
 210
 211    <patched call position>
 212    e51c1120    ldr   r1, [ip, #-288]
 213    e1a0e00f    mov   lr, pc
 214    e51cf124    ldr   pc, [ip, #-292]
 215
 216 *******************************************************************************/
 217
 218 bool patcher_resolve_classref_to_classinfo(patchref_t *pr)
 219 {
 220         constant_classref* cr    = (constant_classref *) pr->ref;
 221         uintptr_t*         datap = (uintptr_t*)          pr->datap;
 222
 223         // Resolve the class.
 224         classinfo* c = resolve_classref_eager(cr);
 225
 226         if (c == NULL)
 227                 return false;
 228
 229         // Patch the classinfo pointer.
 230         *datap = (uintptr_t) c;
 231
 232         // Patch back the original code.
 233         patcher_patch_code(pr);
 234
 235         return true;
 236 }
 237
 238
 239 /* patcher_invokestatic_special ************************************************
 240
 241    Machine code:
 242
 243    <patched call position>
 244    e51cc02c    ldr   ip, [ip, #-44]
 245    e1a0e00f    mov   lr, pc
 246    e1a0f00c    mov   pc, ip
 247
 248 ******************************************************************************/
 249
 250 bool patcher_invokestatic_special(patchref_t *pr)
 251 {
 252         unresolved_method* um    = (unresolved_method*) pr->ref;
 253         uintptr_t*         datap = (uintptr_t*)         pr->datap;
 254
 255         // Reolve the method.
 256         methodinfo* m = resolve_method_eager(um);
 257
 258         if (m == NULL)
 259                 return false;
 260
 261         // Patch stubroutine.
 262         *datap = (uintptr_t) m->stubroutine;
 263
 264         // Patch back the original code.
 265         patcher_patch_code(pr);
 266
 267         return true;
 268 }
 269
 270
 271 /* patcher_invokevirtual *******************************************************
 272
 273    Machine code:
 274
 275    <patched call position>
 276    e590b000    ldr   fp, [r0]
 277    e59bc000    ldr   ip, [fp, #__]
 278    e1a0e00f    mov   lr, pc
 279    e1a0f00c    mov   pc, ip
 280
 281 *******************************************************************************/
 282
 283 bool patcher_invokevirtual(patchref_t *pr)
 284 {
 285         uint32_t*          pc = (uint32_t*)           pr->mpc;
 286         unresolved_method* um = (unresolved_method *) pr->ref;
 287
 288         // Resolve the method.
 289         methodinfo* m = resolve_method_eager(um);
 290
 291         if (m == NULL)
 292                 return false;
 293
 294         // Patch vftbl index.
 295         gen_resolveload(pc[1], (int32_t) (OFFSET(vftbl_t, table[0]) + sizeof(methodptr) * m->vftblindex));
 296
 297         // Synchronize instruction cache.
 298         md_icacheflush(pc + 1, 1 * 4);
 299
 300         // Patch back the original code.
 301         patcher_patch_code(pr);
 302
 303         return true;
 304 }
 305
 306
 307 /* patcher_invokeinterface *****************************************************
 308
 309    Machine code:
 310
 311    <patched call position>
 312    e590b000    ldr   fp, [r0]
 313    e59bb000    ldr   fp, [fp, #__]
 314    e59bc000    ldr   ip, [fp, #__]
 315    e1a0e00f    mov   lr, pc
 316    e1a0f00c    mov   pc, ip
 317
 318
 319 *******************************************************************************/
 320
 321 bool patcher_invokeinterface(patchref_t *pr)
 322 {
 323         unresolved_method* um    = (unresolved_method*) pr->ref;
 324         int32_t*           datap = (int32_t*)           pr->datap;
 325
 326         // Resolve the method.
 327         methodinfo* m = resolve_method_eager(um);
 328
 329         if (m == NULL)
 330                 return false;
 331
 332         // Patch interfacetable index.
 333         int32_t disp = OFFSET(vftbl_t, interfacetable[0]) - sizeof(methodptr*) * m->clazz->index;
 334         *datap = disp;
 335
 336         // HACK The next data segment entry is one below.
 337         datap--;
 338
 339         // Patch method offset.
 340         disp = sizeof(methodptr) * (m - m->clazz->methods);
 341         *datap = disp;
 342
 343         // Patch back the original code.
 344         patcher_patch_code(pr);
 345
 346         return true;
 347 }
 348
 349
 350 /* patcher_checkcast_instanceof_flags ******************************************
 351
 352    Machine code:
 353
 354    <patched call position>
 355
 356 *******************************************************************************/
 357
 358 bool patcher_resolve_classref_to_flags(patchref_t *pr)
 359 {
 360         constant_classref* cr    = (constant_classref*) pr->ref;
 361         int32_t*           datap = (int32_t*)           pr->datap;
 362
 363         // Resolve the class.
 364         classinfo* c = resolve_classref_eager(cr);
 365
 366         if (c == NULL)
 367                 return false;
 368
 369         // Patch class flags.
 370         *datap = (int32_t) c->flags;
 371
 372         // Patch back the original code.
 373         patcher_patch_code(pr);
 374
 375         return true;
 376 }
 377
 378
 379 /* patcher_resolve_classref_to_index *******************************************
 380
 381    Machine code:
 382
 383    <patched call position>
 384
 385 *******************************************************************************/
 386
 387 bool patcher_resolve_classref_to_index(patchref_t *pr)
 388 {
 389         constant_classref* cr    = (constant_classref*) pr->ref;
 390         int32_t*           datap = (int32_t*)           pr->datap;
 391
 392         // Resolve the class.
 393         classinfo* c = resolve_classref_eager(cr);
 394
 395         if (c == NULL)
 396                 return false;
 397
 398         // Patch super class index.
 399         *datap = (int32_t) c->index;
 400
 401         // Patch back the original code.
 402         patcher_patch_code(pr);
 403
 404         return true;
 405 }
 406
 407
 408 /* patcher_resolve_classref_to_vftbl *******************************************
 409
 410    Machine code:
 411
 412    <patched call position>
 413
 414 *******************************************************************************/
 415
 416 bool patcher_resolve_classref_to_vftbl(patchref_t *pr)
 417 {
 418         constant_classref* cr    = (constant_classref*) pr->ref;
 419         uintptr_t*         datap = (uintptr_t*)         pr->datap;
 420
 421         // Resolve the class.
 422
 423         classinfo* c = resolve_classref_eager(cr);
 424
 425         if (c == NULL)
 426                 return false;
 427
 428         // Patch super class' vftbl.
 429         *datap = (uintptr_t) c->vftbl;
 430
 431         // Patch back the original code.
 432         patcher_patch_code(pr);
 433
 434         return true;
 435 }
 436
 437
 438 /*
 439  * These are local overrides for various environment variables in Emacs.
 440  * Please do not remove this and leave it at the end of the file, where
 441  * Emacs will automagically detect them.
 442  * ---------------------------------------------------------------------
 443  * Local variables:
 444  * mode: c
 445  * indent-tabs-mode: t
 446  * c-basic-offset: 4
 447  * tab-width: 4
 448  * End:
 449  * vim:noexpandtab:sw=4:ts=4:
 450  */