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

   1 /* src/vm/jit/i386/freebsd/md-os.c - machine dependent i386 FreeBSD functions
   2
   3    Copyright (C) 1996-2005, 2006, 2007, 2008
   4    CACAOVM - Verein zur Foerderung der freien virtuellen Maschine CACAO
   5
   6    This file is part of CACAO.
   7
   8    This program is free software; you can redistribute it and/or
   9    modify it under the terms of the GNU General Public License as
  10    published by the Free Software Foundation; either version 2, or (at
  11    your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful, but
  14    WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16    General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program; if not, write to the Free Software
  20    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  21    02110-1301, USA.
  22
  23 */
  24
  25
  26 #include "config.h"
  27
  28 #include <stdint.h>
  29 #include <ucontext.h>
  30
  31 #include "vm/types.h"
  32
  33 #include "vm/jit/i386/codegen.h"
  34 #include "vm/jit/i386/md.h"
  35
  36 #include "threads/thread.hpp"
  37
  38 #include "vm/jit/builtin.hpp"
  39 #include "vm/signallocal.hpp"
  40
  41 #include "vm/jit/asmpart.h"
  42 #include "vm/jit/executionstate.h"
  43 #include "vm/jit/stacktrace.hpp"
  44 #include "vm/jit/trap.hpp"
  45
  46
  47 /* md_signal_handler_sigsegv ***************************************************
  48
  49    Signal handler for hardware exceptions.
  50
  51 *******************************************************************************/
  52
  53 void md_signal_handler_sigsegv(int sig, siginfo_t *siginfo, void *_p)
  54 {
  55         ucontext_t     *_uc;
  56         mcontext_t     *_mc;
  57         u1             *pv;
  58         u1             *sp;
  59         u1             *ra;
  60         u1             *xpc;
  61         u1              opc;
  62         u1              mod;
  63         u1              rm;
  64         s4              d;
  65         s4              disp;
  66         ptrint          val;
  67         s4              type;
  68         void           *p;
  69
  70         _uc = (ucontext_t *) _p;
  71         _mc = &_uc->uc_mcontext;
  72
  73         pv  = NULL;                 /* is resolved during stackframeinfo creation */
  74         sp  = (u1 *) _mc->mc_esp;
  75         xpc = (u1 *) _mc->mc_eip;
  76         ra  = xpc;                              /* return address is equal to XPC */
  77
  78         /* get exception-throwing instruction */
  79
  80         opc = M_ALD_MEM_GET_OPC(xpc);
  81         mod = M_ALD_MEM_GET_MOD(xpc);
  82         rm  = M_ALD_MEM_GET_RM(xpc);
  83
  84         /* for values see emit_mov_mem_reg and emit_mem */
  85
  86         if ((opc == 0x8b) && (mod == 0) && (rm == 5)) {
  87                 /* this was a hardware-exception */
  88
  89                 d    = M_ALD_MEM_GET_REG(xpc);
  90                 disp = M_ALD_MEM_GET_DISP(xpc);
  91
  92                 /* we use the exception type as load displacement */
  93
  94                 type = disp;
  95
  96                 switch (d) {
  97                 case EAX:
  98                         val = _mc->mc_eax;
  99                         break;
 100                 case ECX:
 101                         val = _mc->mc_ecx;
 102                         break;
 103                 case EDX:
 104                         val = _mc->mc_edx;
 105                         break;
 106                 case EBX:
 107                         val = _mc->mc_ebx;
 108                         break;
 109                 case ESP:
 110                         val = _mc->mc_esp;
 111                         break;
 112                 case EBP:
 113                         val = _mc->mc_ebp;
 114                         break;
 115                 case ESI:
 116                         val = _mc->mc_esi;
 117                         break;
 118                 case EDI:
 119                         val = _mc->mc_edi;
 120                         break;
 121                 default:
 122                         vm_abort("md_signal_handler_sigsegv: Unkown register %d", d);
 123                 }
 124
 125                 if (type == TRAP_COMPILER) {
 126                         /* The PV from the compiler stub is equal to the XPC. */
 127
 128                         pv = xpc;
 129
 130                         /* We use a framesize of zero here because the call pushed
 131                            the return addres onto the stack. */
 132
 133                         ra = md_stacktrace_get_returnaddress(sp, 0);
 134
 135                         /* Skip the RA on the stack. */
 136
 137                         sp = sp + 1 * SIZEOF_VOID_P;
 138
 139                         /* The XPC is the RA minus 2, because the RA points to the
 140                            instruction after the call. */
 141
 142                         xpc = ra - 2;
 143                 }
 144         }
 145         else {
 146                 /* this was a normal NPE */
 147
 148                 type = TRAP_NullPointerException;
 149                 val  = 0;
 150         }
 151
 152         /* Handle the trap. */
 153
 154         p = trap_handle(type, val, pv, sp, ra, xpc, _p);
 155
 156         /* Set registers. */
 157
 158         if (type == TRAP_COMPILER) {
 159                 if (p == NULL) {
 160                         _mc->mc_esp = (uintptr_t) sp; // Remove RA from stack.
 161                 }
 162         }
 163 }
 164
 165
 166 /* md_signal_handler_sigfpe ****************************************************
 167
 168    ArithmeticException signal handler for hardware divide by zero
 169    check.
 170
 171 *******************************************************************************/
 172
 173 void md_signal_handler_sigfpe(int sig, siginfo_t *siginfo, void *_p)
 174 {
 175         ucontext_t     *_uc;
 176         mcontext_t     *_mc;
 177         u1             *pv;
 178         u1             *sp;
 179         u1             *ra;
 180         u1             *xpc;
 181         s4              type;
 182         ptrint          val;
 183
 184         _uc = (ucontext_t *) _p;
 185         _mc = &_uc->uc_mcontext;
 186
 187         pv  = NULL;                 /* is resolved during stackframeinfo creation */
 188         sp  = (u1 *) _mc->mc_esp;
 189         xpc = (u1 *) _mc->mc_eip;
 190         ra  = xpc;                          /* return address is equal to xpc     */
 191
 192         /* This is an ArithmeticException. */
 193
 194         type = TRAP_ArithmeticException;
 195         val  = 0;
 196
 197         /* Handle the trap. */
 198
 199         trap_handle(type, val, pv, sp, ra, xpc, _p);
 200 }
 201
 202
 203 /* md_signal_handler_sigill ****************************************************
 204
 205    Signal handler for hardware patcher traps (ud2).
 206
 207 *******************************************************************************/
 208
 209 void md_signal_handler_sigill(int sig, siginfo_t *siginfo, void *_p)
 210 {
 211         ucontext_t        *_uc;
 212         mcontext_t        *_mc;
 213         u1                *pv;
 214         u1                *sp;
 215         u1                *ra;
 216         u1                *xpc;
 217         s4                 type;
 218         ptrint             val;
 219
 220         _uc = (ucontext_t *) _p;
 221         _mc = &_uc->uc_mcontext;
 222
 223         pv  = NULL;                 /* is resolved during stackframeinfo creation */
 224         sp  = (u1 *) _mc->mc_esp;
 225         xpc = (u1 *) _mc->mc_eip;
 226         ra  = xpc;                            /* return address is equal to xpc   */
 227
 228         // Check if the trap instruction is valid.
 229         // TODO Move this into patcher_handler.
 230         if (patcher_is_valid_trap_instruction_at(xpc) == false) {
 231                 // Check if the PC has been patched during our way to this
 232                 // signal handler (see PR85).
 233                 if (patcher_is_patched_at(xpc) == true)
 234                         return;
 235
 236                 // We have a problem...
 237                 log_println("md_signal_handler_sigill: Unknown illegal instruction at 0x%lx", xpc);
 238 #if defined(ENABLE_DISASSEMBLER)
 239                 (void) disassinstr(xpc);
 240 #endif
 241                 vm_abort("Aborting...");
 242         }
 243
 244         type = TRAP_PATCHER;
 245         val  = 0;
 246
 247         /* Handle the trap. */
 248
 249         trap_handle(type, val, pv, sp, ra, xpc, _p);
 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->mc_eip;
 272         sp = (u1 *) _mc->mc_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->mc_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 = (ucontext_t*) context;
 315         mcontext_t* _mc = &_uc->uc_mcontext;
 316
 317         // Read special registers.
 318         es->pc = (u1 *) _mc->mc_eip;
 319         es->sp = (u1 *) _mc->mc_esp;
 320         es->pv = NULL;                   /* pv must be looked up via AVL tree */
 321
 322         // Read integer registers.
 323         es->intregs[EAX] = _mc->mc_eax;
 324         es->intregs[ECX] = _mc->mc_ecx;
 325         es->intregs[EDX] = _mc->mc_edx;
 326         es->intregs[EBX] = _mc->mc_ebx;
 327         es->intregs[ESP] = _mc->mc_esp;
 328         es->intregs[EBP] = _mc->mc_ebp;
 329         es->intregs[ESI] = _mc->mc_esi;
 330         es->intregs[EDI] = _mc->mc_edi;
 331
 332         // Read float registers.
 333         for (int i = 0; i < FLT_REG_CNT; i++)
 334                 es->fltregs[i] = 0xdeadbeefdeadbeefULL;
 335 }
 336
 337
 338 /* md_executionstate_write *****************************************************
 339
 340    Write the given executionstate back to the context for Replacement.
 341
 342 *******************************************************************************/
 343
 344 void md_executionstate_write(executionstate_t* es, void* context)
 345 {
 346         ucontext_t* _uc = (ucontext_t*) context;
 347         mcontext_t* _mc = &_uc->uc_mcontext;
 348
 349         // Write integer registers.
 350         _mc->mc_eax = es->intregs[EAX];
 351         _mc->mc_ecx = es->intregs[ECX];
 352         _mc->mc_edx = es->intregs[EDX];
 353         _mc->mc_ebx = es->intregs[EBX];
 354         _mc->mc_esp = es->intregs[ESP];
 355         _mc->mc_ebp = es->intregs[EBP];
 356         _mc->mc_esi = es->intregs[ESI];
 357         _mc->mc_edi = es->intregs[EDI];
 358
 359         // Write special registers.
 360         _mc->mc_eip = (uintptr_t) es->pc;
 361         _mc->mc_esp = (uintptr_t) es->sp;
 362 }
 363
 364
 365 /*
 366  * These are local overrides for various environment variables in Emacs.
 367  * Please do not remove this and leave it at the end of the file, where
 368  * Emacs will automagically detect them.
 369  * ---------------------------------------------------------------------
 370  * Local variables:
 371  * mode: c
 372  * indent-tabs-mode: t
 373  * c-basic-offset: 4
 374  * tab-width: 4
 375  * End:
 376  */