src/vm/jit/i386/linux/md-os.c

   1 /* src/vm/jit/i386/linux/md-os.c - machine dependent i386 Linux functions
   2
   3    Copyright (C) 1996-2005, 2006, 2007 R. Grafl, A. Krall, C. Kruegel,
   4    C. Oates, R. Obermaisser, M. Platter, M. Probst, S. Ring,
   5    E. Steiner, C. Thalinger, D. Thuernbeck, P. Tomsich, C. Ullrich,
   6    J. Wenninger, Institut f. Computersprachen - TU Wien
   7
   8    This file is part of CACAO.
   9
  10    This program is free software; you can redistribute it and/or
  11    modify it under the terms of the GNU General Public License as
  12    published by the Free Software Foundation; either version 2, or (at
  13    your option) any later version.
  14
  15    This program is distributed in the hope that it will be useful, but
  16    WITHOUT ANY WARRANTY; without even the implied warranty of
  17    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  18    General Public License for more details.
  19
  20    You should have received a copy of the GNU General Public License
  21    along with this program; if not, write to the Free Software
  22    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  23    02110-1301, USA.
  24
  25 */
  26
  27
  28 #define _GNU_SOURCE                   /* include REG_ defines from ucontext.h */
  29
  30 #include "config.h"
  31
  32 #include <stdint.h>
  33 #include <ucontext.h>
  34
  35 #include "vm/types.h"
  36
  37 #include "vm/jit/i386/codegen.h"
  38 #include "vm/jit/i386/md.h"
  39
  40 #include "threads/threads-common.h"
  41
  42 #include "vm/builtin.h"
  43 #include "vm/exceptions.h"
  44 #include "vm/signallocal.h"
  45 #include "vm/stringlocal.h"
  46
  47 #include "vm/jit/asmpart.h"
  48 #include "vm/jit/executionstate.h"
  49 #include "vm/jit/stacktrace.h"
  50
  51
  52 /* md_signal_handler_sigsegv ***************************************************
  53
  54    Signal handler for hardware exceptions.
  55
  56 *******************************************************************************/
  57
  58 void md_signal_handler_sigsegv(int sig, siginfo_t *siginfo, void *_p)
  59 {
  60         ucontext_t     *_uc;
  61         mcontext_t     *_mc;
  62         u1             *pv;
  63         u1             *sp;
  64         u1             *ra;
  65         u1             *xpc;
  66         u1              opc;
  67         u1              mod;
  68         u1              rm;
  69         s4              d;
  70         s4              disp;
  71         ptrint          val;
  72         s4              type;
  73         void           *p;
  74         java_object_t  *o;
  75
  76         _uc = (ucontext_t *) _p;
  77         _mc = &_uc->uc_mcontext;
  78
  79         pv  = NULL;                 /* is resolved during stackframeinfo creation */
  80         sp  = (u1 *) _mc->gregs[REG_ESP];
  81         xpc = (u1 *) _mc->gregs[REG_EIP];
  82         ra  = xpc;                              /* return address is equal to XPC */
  83
  84         /* get exception-throwing instruction */
  85
  86         opc = M_ALD_MEM_GET_OPC(xpc);
  87         mod = M_ALD_MEM_GET_MOD(xpc);
  88         rm  = M_ALD_MEM_GET_RM(xpc);
  89
  90         /* for values see emit_mov_mem_reg and emit_mem */
  91
  92         if ((opc == 0x8b) && (mod == 0) && (rm == 5)) {
  93                 /* this was a hardware-exception */
  94
  95                 d    = M_ALD_MEM_GET_REG(xpc);
  96                 disp = M_ALD_MEM_GET_DISP(xpc);
  97
  98                 /* we use the exception type as load displacement */
  99
 100                 type = disp;
 101
 102                 /* ATTENTION: The _mc->gregs layout is completely crazy!  The
 103                    registers are reversed starting with number 4 for REG_EDI
 104                    (see /usr/include/sys/ucontext.h).  We have to convert that
 105                    here. */
 106
 107                 val = _mc->gregs[REG_EAX - d];
 108
 109                 if (type == EXCEPTION_HARDWARE_COMPILER) {
 110                         /* The PV from the compiler stub is equal to the XPC. */
 111
 112                         pv = xpc;
 113
 114                         /* We use a framesize of zero here because the call pushed
 115                            the return addres onto the stack. */
 116
 117                         ra = md_stacktrace_get_returnaddress(sp, 0);
 118
 119                         /* Skip the RA on the stack. */
 120
 121                         sp = sp + 1 * SIZEOF_VOID_P;
 122
 123                         /* The XPC is the RA minus 2, because the RA points to the
 124                            instruction after the call. */
 125
 126                         xpc = ra - 2;
 127                 }
 128         }
 129         else {
 130                 /* this was a normal NPE */
 131
 132                 type = EXCEPTION_HARDWARE_NULLPOINTER;
 133                 val  = 0;
 134         }
 135
 136         /* Handle the type. */
 137
 138         p = signal_handle(type, val, pv, sp, ra, xpc, _p);
 139
 140         /* Set registers. */
 141
 142         if (type == EXCEPTION_HARDWARE_COMPILER) {
 143                 if (p == NULL) {
 144                         o = builtin_retrieve_exception();
 145
 146                         _mc->gregs[REG_ESP] = (uintptr_t) sp;    /* Remove RA from stack. */
 147
 148                         _mc->gregs[REG_EAX] = (uintptr_t) o;
 149                         _mc->gregs[REG_ECX] = (uintptr_t) xpc;           /* REG_ITMP2_XPC */
 150                         _mc->gregs[REG_EIP] = (uintptr_t) asm_handle_exception;
 151                 }
 152                 else {
 153                         _mc->gregs[REG_EIP] = (uintptr_t) p;
 154                 }
 155         }
 156         else {
 157                 _mc->gregs[REG_EAX] = (intptr_t) p;
 158                 _mc->gregs[REG_ECX] = (intptr_t) xpc;                /* REG_ITMP2_XPC */
 159                 _mc->gregs[REG_EIP] = (intptr_t) asm_handle_exception;
 160         }
 161 }
 162
 163
 164 /* md_signal_handler_sigfpe ****************************************************
 165
 166    ArithmeticException signal handler for hardware divide by zero
 167    check.
 168
 169 *******************************************************************************/
 170
 171 void md_signal_handler_sigfpe(int sig, siginfo_t *siginfo, void *_p)
 172 {
 173         ucontext_t     *_uc;
 174         mcontext_t     *_mc;
 175         u1             *pv;
 176         u1             *sp;
 177         u1             *ra;
 178         u1             *xpc;
 179         s4              type;
 180         ptrint          val;
 181         void           *p;
 182
 183         _uc = (ucontext_t *) _p;
 184         _mc = &_uc->uc_mcontext;
 185
 186         pv  = NULL;                 /* is resolved during stackframeinfo creation */
 187         sp  = (u1 *) _mc->gregs[REG_ESP];
 188         xpc = (u1 *) _mc->gregs[REG_EIP];
 189         ra  = xpc;                          /* return address is equal to xpc     */
 190
 191         /* this is an ArithmeticException */
 192
 193         type = EXCEPTION_HARDWARE_ARITHMETIC;
 194         val  = 0;
 195
 196         /* Handle the type. */
 197
 198         p = signal_handle(type, val, pv, sp, ra, xpc, _p);
 199
 200         /* set registers */
 201
 202         _mc->gregs[REG_EAX] = (intptr_t) p;
 203         _mc->gregs[REG_ECX] = (intptr_t) xpc;                    /* REG_ITMP2_XPC */
 204         _mc->gregs[REG_EIP] = (intptr_t) asm_handle_exception;
 205 }
 206
 207
 208 /* md_signal_handler_sigill ****************************************************
 209
 210    Signal handler for hardware patcher traps (ud2).
 211
 212 *******************************************************************************/
 213
 214 void md_signal_handler_sigill(int sig, siginfo_t *siginfo, void *_p)
 215 {
 216         ucontext_t        *_uc;
 217         mcontext_t        *_mc;
 218         u1                *pv;
 219         u1                *sp;
 220         u1                *ra;
 221         u1                *xpc;
 222         s4                 type;
 223         ptrint             val;
 224         void              *p;
 225
 226         _uc = (ucontext_t *) _p;
 227         _mc = &_uc->uc_mcontext;
 228
 229         pv  = NULL;                 /* is resolved during stackframeinfo creation */
 230         sp  = (u1 *) _mc->gregs[REG_ESP];
 231         xpc = (u1 *) _mc->gregs[REG_EIP];
 232         ra  = xpc;                            /* return address is equal to xpc   */
 233
 234         /* this is an ArithmeticException */
 235
 236         type = EXCEPTION_HARDWARE_PATCHER;
 237         val  = 0;
 238
 239         /* generate appropriate exception */
 240
 241         p = signal_handle(type, val, pv, sp, ra, xpc, _p);
 242
 243         /* set registers (only if exception object ready) */
 244
 245         if (p != NULL) {
 246                 _mc->gregs[REG_EAX] = (ptrint) p;
 247                 _mc->gregs[REG_ECX] = (ptrint) xpc;                      /* REG_ITMP2_XPC */
 248                 _mc->gregs[REG_EIP] = (ptrint) asm_handle_exception;
 249         }
 250 }
 251
 252
 253 /* md_signal_handler_sigusr1 ***************************************************
 254
 255    Signal handler for suspending threads.
 256
 257 *******************************************************************************/
 258
 259 #if defined(ENABLE_THREADS) && defined(ENABLE_GC_CACAO)
 260 void md_signal_handler_sigusr1(int sig, siginfo_t *siginfo, void *_p)
 261 {
 262         ucontext_t *_uc;
 263         mcontext_t *_mc;
 264         u1         *pc;
 265         u1         *sp;
 266
 267         _uc = (ucontext_t *) _p;
 268         _mc = &_uc->uc_mcontext;
 269
 270         /* get the PC and SP for this thread */
 271         pc = (u1 *) _mc->gregs[REG_EIP];
 272         sp = (u1 *) _mc->gregs[REG_ESP];
 273
 274         /* now suspend the current thread */
 275         threads_suspend_ack(pc, sp);
 276 }
 277 #endif
 278
 279
 280 /* md_signal_handler_sigusr2 ***************************************************
 281
 282    Signal handler for profiling sampling.
 283
 284 *******************************************************************************/
 285
 286 #if defined(ENABLE_THREADS)
 287 void md_signal_handler_sigusr2(int sig, siginfo_t *siginfo, void *_p)
 288 {
 289         threadobject *t;
 290         ucontext_t   *_uc;
 291         mcontext_t   *_mc;
 292         u1           *pc;
 293
 294         t = THREADOBJECT;
 295
 296         _uc = (ucontext_t *) _p;
 297         _mc = &_uc->uc_mcontext;
 298
 299         pc = (u1 *) _mc->gregs[REG_EIP];
 300
 301         t->pc = pc;
 302 }
 303 #endif
 304
 305
 306 /* md_executionstate_read ******************************************************
 307
 308    Read the given context into an executionstate for Replacement.
 309
 310 *******************************************************************************/
 311
 312 void md_executionstate_read(executionstate_t *es, void *context)
 313 {
 314         ucontext_t *_uc;
 315         mcontext_t *_mc;
 316         s4          i;
 317
 318         _uc = (ucontext_t *) context;
 319         _mc = &_uc->uc_mcontext;
 320
 321         /* read special registers */
 322         es->pc = (u1 *) _mc->gregs[REG_EIP];
 323         es->sp = (u1 *) _mc->gregs[REG_ESP];
 324         es->pv = NULL;                   /* pv must be looked up via AVL tree */
 325
 326         /* read integer registers */
 327         for (i = 0; i < INT_REG_CNT; i++)
 328                 es->intregs[i] = _mc->gregs[REG_EAX - i];
 329
 330         /* read float registers */
 331         for (i = 0; i < FLT_REG_CNT; i++)
 332                 es->fltregs[i] = 0xdeadbeefdeadbeefULL;
 333 }
 334
 335
 336 /* md_executionstate_write *****************************************************
 337
 338    Write the given executionstate back to the context for Replacement.
 339
 340 *******************************************************************************/
 341
 342 void md_executionstate_write(executionstate_t *es, void *context)
 343 {
 344         ucontext_t *_uc;
 345         mcontext_t *_mc;
 346         s4          i;
 347
 348         _uc = (ucontext_t *) context;
 349         _mc = &_uc->uc_mcontext;
 350
 351         /* write integer registers */
 352         for (i = 0; i < INT_REG_CNT; i++)
 353                 _mc->gregs[REG_EAX - i] = es->intregs[i];
 354
 355         /* write special registers */
 356         _mc->gregs[REG_EIP] = (ptrint) es->pc;
 357         _mc->gregs[REG_ESP] = (ptrint) es->sp;
 358 }
 359
 360
 361 /* md_critical_section_restart *************************************************
 362
 363    Search the critical sections tree for a matching section and set
 364    the PC to the restart point, if necessary.
 365
 366 *******************************************************************************/
 367
 368 #if defined(ENABLE_THREADS)
 369 void md_critical_section_restart(ucontext_t *_uc)
 370 {
 371         mcontext_t *_mc;
 372         u1         *pc;
 373         u1         *npc;
 374
 375         _mc = &_uc->uc_mcontext;
 376
 377         pc = (u1 *) _mc->gregs[REG_EIP];
 378
 379         npc = critical_find_restart_point(pc);
 380
 381         if (npc != NULL)
 382                 _mc->gregs[REG_EIP] = (ptrint) npc;
 383 }
 384 #endif
 385
 386
 387 /*
 388  * These are local overrides for various environment variables in Emacs.
 389  * Please do not remove this and leave it at the end of the file, where
 390  * Emacs will automagically detect them.
 391  * ---------------------------------------------------------------------
 392  * Local variables:
 393  * mode: c
 394  * indent-tabs-mode: t
 395  * c-basic-offset: 4
 396  * tab-width: 4
 397  * End:
 398  */