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/stacktrace.h"
  49
  50
  51 /* md_signal_handler_sigsegv ***************************************************
  52
  53    Signal handler for hardware exceptions.
  54
  55 *******************************************************************************/
  56
  57 void md_signal_handler_sigsegv(int sig, siginfo_t *siginfo, void *_p)
  58 {
  59         ucontext_t     *_uc;
  60         mcontext_t     *_mc;
  61         u1             *pv;
  62         u1             *sp;
  63         u1             *ra;
  64         u1             *xpc;
  65         u1              opc;
  66         u1              mod;
  67         u1              rm;
  68         s4              d;
  69         s4              disp;
  70         ptrint          val;
  71         s4              type;
  72         void           *p;
  73         java_object_t  *o;
  74
  75         _uc = (ucontext_t *) _p;
  76         _mc = &_uc->uc_mcontext;
  77
  78         pv  = NULL;                 /* is resolved during stackframeinfo creation */
  79         sp  = (u1 *) _mc->gregs[REG_ESP];
  80         xpc = (u1 *) _mc->gregs[REG_EIP];
  81         ra  = xpc;                              /* return address is equal to XPC */
  82
  83         /* get exception-throwing instruction */
  84
  85         opc = M_ALD_MEM_GET_OPC(xpc);
  86         mod = M_ALD_MEM_GET_MOD(xpc);
  87         rm  = M_ALD_MEM_GET_RM(xpc);
  88
  89         /* for values see emit_mov_mem_reg and emit_mem */
  90
  91         if ((opc == 0x8b) && (mod == 0) && (rm == 5)) {
  92                 /* this was a hardware-exception */
  93
  94                 d    = M_ALD_MEM_GET_REG(xpc);
  95                 disp = M_ALD_MEM_GET_DISP(xpc);
  96
  97                 /* we use the exception type as load displacement */
  98
  99                 type = disp;
 100
 101                 /* ATTENTION: The _mc->gregs layout is completely crazy!  The
 102                    registers are reversed starting with number 4 for REG_EDI
 103                    (see /usr/include/sys/ucontext.h).  We have to convert that
 104                    here. */
 105
 106                 val = _mc->gregs[REG_EAX - d];
 107
 108                 if (type == EXCEPTION_HARDWARE_COMPILER) {
 109                         /* The PV from the compiler stub is equal to the XPC. */
 110
 111                         pv = xpc;
 112
 113                         /* We use a framesize of zero here because the call pushed
 114                            the return addres onto the stack. */
 115
 116                         ra = md_stacktrace_get_returnaddress(sp, 0);
 117
 118                         /* Skip the RA on the stack. */
 119
 120                         sp = sp + 1 * SIZEOF_VOID_P;
 121
 122                         /* The XPC is the RA minus 2, because the RA points to the
 123                            instruction after the call. */
 124
 125                         xpc = ra - 2;
 126                 }
 127         }
 128         else {
 129                 /* this was a normal NPE */
 130
 131                 type = EXCEPTION_HARDWARE_NULLPOINTER;
 132                 val  = 0;
 133         }
 134
 135         /* Handle the type. */
 136
 137         p = signal_handle(type, val, pv, sp, ra, xpc, _p);
 138
 139         /* Set registers. */
 140
 141         if (type == EXCEPTION_HARDWARE_COMPILER) {
 142                 if (p == NULL) {
 143                         o = builtin_retrieve_exception();
 144
 145                         _mc->gregs[REG_ESP] = (uintptr_t) sp;    /* Remove RA from stack. */
 146
 147                         _mc->gregs[REG_EAX] = (uintptr_t) o;
 148                         _mc->gregs[REG_ECX] = (uintptr_t) xpc;           /* REG_ITMP2_XPC */
 149                         _mc->gregs[REG_EIP] = (uintptr_t) asm_handle_exception;
 150                 }
 151                 else {
 152                         _mc->gregs[REG_EIP] = (uintptr_t) p;
 153                 }
 154         }
 155         else {
 156                 _mc->gregs[REG_EAX] = (intptr_t) p;
 157                 _mc->gregs[REG_ECX] = (intptr_t) xpc;                /* REG_ITMP2_XPC */
 158                 _mc->gregs[REG_EIP] = (intptr_t) asm_handle_exception;
 159         }
 160 }
 161
 162
 163 /* md_signal_handler_sigfpe ****************************************************
 164
 165    ArithmeticException signal handler for hardware divide by zero
 166    check.
 167
 168 *******************************************************************************/
 169
 170 void md_signal_handler_sigfpe(int sig, siginfo_t *siginfo, void *_p)
 171 {
 172         ucontext_t     *_uc;
 173         mcontext_t     *_mc;
 174         u1             *pv;
 175         u1             *sp;
 176         u1             *ra;
 177         u1             *xpc;
 178         s4              type;
 179         ptrint          val;
 180         void           *p;
 181
 182         _uc = (ucontext_t *) _p;
 183         _mc = &_uc->uc_mcontext;
 184
 185         pv  = NULL;                 /* is resolved during stackframeinfo creation */
 186         sp  = (u1 *) _mc->gregs[REG_ESP];
 187         xpc = (u1 *) _mc->gregs[REG_EIP];
 188         ra  = xpc;                          /* return address is equal to xpc     */
 189
 190         /* this is an ArithmeticException */
 191
 192         type = EXCEPTION_HARDWARE_ARITHMETIC;
 193         val  = 0;
 194
 195         /* Handle the type. */
 196
 197         p = signal_handle(type, val, pv, sp, ra, xpc, _p);
 198
 199         /* set registers */
 200
 201         _mc->gregs[REG_EAX] = (intptr_t) p;
 202         _mc->gregs[REG_ECX] = (intptr_t) xpc;                    /* REG_ITMP2_XPC */
 203         _mc->gregs[REG_EIP] = (intptr_t) asm_handle_exception;
 204 }
 205
 206
 207 /* md_signal_handler_sigill ****************************************************
 208
 209    Signal handler for hardware patcher traps (ud2).
 210
 211 *******************************************************************************/
 212
 213 void md_signal_handler_sigill(int sig, siginfo_t *siginfo, void *_p)
 214 {
 215         ucontext_t        *_uc;
 216         mcontext_t        *_mc;
 217         u1                *pv;
 218         u1                *sp;
 219         u1                *ra;
 220         u1                *xpc;
 221         s4                 type;
 222         ptrint             val;
 223         void              *p;
 224
 225         _uc = (ucontext_t *) _p;
 226         _mc = &_uc->uc_mcontext;
 227
 228         pv  = NULL;                 /* is resolved during stackframeinfo creation */
 229         sp  = (u1 *) _mc->gregs[REG_ESP];
 230         xpc = (u1 *) _mc->gregs[REG_EIP];
 231         ra  = xpc;                            /* return address is equal to xpc   */
 232
 233         /* this is an ArithmeticException */
 234
 235         type = EXCEPTION_HARDWARE_PATCHER;
 236         val  = 0;
 237
 238         /* generate appropriate exception */
 239
 240         p = signal_handle(type, val, pv, sp, ra, xpc, _p);
 241
 242         /* set registers (only if exception object ready) */
 243
 244         if (p != NULL) {
 245                 _mc->gregs[REG_EAX] = (ptrint) p;
 246                 _mc->gregs[REG_ECX] = (ptrint) xpc;                      /* REG_ITMP2_XPC */
 247                 _mc->gregs[REG_EIP] = (ptrint) asm_handle_exception;
 248         }
 249 }
 250
 251
 252 /* md_signal_handler_sigusr1 ***************************************************
 253
 254    Signal handler for suspending threads.
 255
 256 *******************************************************************************/
 257
 258 #if defined(ENABLE_THREADS) && defined(ENABLE_GC_CACAO)
 259 void md_signal_handler_sigusr1(int sig, siginfo_t *siginfo, void *_p)
 260 {
 261         ucontext_t *_uc;
 262         mcontext_t *_mc;
 263         u1         *pc;
 264         u1         *sp;
 265
 266         _uc = (ucontext_t *) _p;
 267         _mc = &_uc->uc_mcontext;
 268
 269         /* get the PC and SP for this thread */
 270         pc = (u1 *) _mc->gregs[REG_EIP];
 271         sp = (u1 *) _mc->gregs[REG_ESP];
 272
 273         /* now suspend the current thread */
 274         threads_suspend_ack(pc, sp);
 275 }
 276 #endif
 277
 278
 279 /* md_signal_handler_sigusr2 ***************************************************
 280
 281    Signal handler for profiling sampling.
 282
 283 *******************************************************************************/
 284
 285 #if defined(ENABLE_THREADS)
 286 void md_signal_handler_sigusr2(int sig, siginfo_t *siginfo, void *_p)
 287 {
 288         threadobject *t;
 289         ucontext_t   *_uc;
 290         mcontext_t   *_mc;
 291         u1           *pc;
 292
 293         t = THREADOBJECT;
 294
 295         _uc = (ucontext_t *) _p;
 296         _mc = &_uc->uc_mcontext;
 297
 298         pc = (u1 *) _mc->gregs[REG_EIP];
 299
 300         t->pc = pc;
 301 }
 302 #endif
 303
 304
 305 /* md_replace_executionstate_read **********************************************
 306
 307    Read the given context into an executionstate for Replacement.
 308
 309 *******************************************************************************/
 310
 311 #if defined(ENABLE_REPLACEMENT)
 312 void md_replace_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 #endif
 335
 336
 337 /* md_replace_executionstate_write *********************************************
 338
 339    Write the given executionstate back to the context for Replacement.
 340
 341 *******************************************************************************/
 342
 343 #if defined(ENABLE_REPLACEMENT)
 344 void md_replace_executionstate_write(executionstate_t *es, void *context)
 345 {
 346         ucontext_t *_uc;
 347         mcontext_t *_mc;
 348         s4          i;
 349
 350         _uc = (ucontext_t *) context;
 351         _mc = &_uc->uc_mcontext;
 352
 353         /* write integer registers */
 354         for (i = 0; i < INT_REG_CNT; i++)
 355                 _mc->gregs[REG_EAX - i] = es->intregs[i];
 356
 357         /* write special registers */
 358         _mc->gregs[REG_EIP] = (ptrint) es->pc;
 359         _mc->gregs[REG_ESP] = (ptrint) es->sp;
 360 }
 361 #endif
 362
 363
 364 /* md_critical_section_restart *************************************************
 365
 366    Search the critical sections tree for a matching section and set
 367    the PC to the restart point, if necessary.
 368
 369 *******************************************************************************/
 370
 371 #if defined(ENABLE_THREADS)
 372 void md_critical_section_restart(ucontext_t *_uc)
 373 {
 374         mcontext_t *_mc;
 375         u1         *pc;
 376         u1         *npc;
 377
 378         _mc = &_uc->uc_mcontext;
 379
 380         pc = (u1 *) _mc->gregs[REG_EIP];
 381
 382         npc = critical_find_restart_point(pc);
 383
 384         if (npc != NULL)
 385                 _mc->gregs[REG_EIP] = (ptrint) npc;
 386 }
 387 #endif
 388
 389
 390 /*
 391  * These are local overrides for various environment variables in Emacs.
 392  * Please do not remove this and leave it at the end of the file, where
 393  * Emacs will automagically detect them.
 394  * ---------------------------------------------------------------------
 395  * Local variables:
 396  * mode: c
 397  * indent-tabs-mode: t
 398  * c-basic-offset: 4
 399  * tab-width: 4
 400  * End:
 401  */