mono/mini/exceptions-s390x.c

   1 /**
   2  * \file
   3  *
   4  * Function    - Exception support for S/390.
   5  *
   6  * Name        - Neale Ferguson (Neale.Ferguson@SoftwareAG-usa.com)
   7  *
   8  * Date        - January, 2004
   9  *
  10  * Derivation  - From exceptions-x86 & exceptions-ppc
  11  *               Paolo Molaro (lupus@ximian.com)
  12  *               Dietmar Maurer (dietmar@ximian.com)
  13  *
  14  * Copyright   - 2001 Ximian, Inc.
  15  * Licensed under the MIT license. See LICENSE file in the project root for full license information.
  16  *
  17  */
  18
  19 /*------------------------------------------------------------------*/
  20 /*                 D e f i n e s                                    */
  21 /*------------------------------------------------------------------*/
  22
  23 #define S390_CALLFILTER_INTREGS         S390_MINIMAL_STACK_SIZE
  24 #define S390_CALLFILTER_FLTREGS         (S390_CALLFILTER_INTREGS+(16*sizeof(gulong)))
  25 #define S390_CALLFILTER_ACCREGS         (S390_CALLFILTER_FLTREGS+(16*sizeof(gdouble)))
  26 #define S390_CALLFILTER_SIZE            (S390_CALLFILTER_ACCREGS+(16*sizeof(gint32)))
  27
  28 #define S390_THROWSTACK_ACCPRM          S390_MINIMAL_STACK_SIZE
  29 #define S390_THROWSTACK_FPCPRM          (S390_THROWSTACK_ACCPRM+sizeof(gpointer))
  30 #define S390_THROWSTACK_RETHROW         (S390_THROWSTACK_FPCPRM+sizeof(gulong))
  31 #define S390_THROWSTACK_INTREGS         (S390_THROWSTACK_RETHROW+sizeof(gboolean))
  32 #define S390_THROWSTACK_FLTREGS         (S390_THROWSTACK_INTREGS+(16*sizeof(gulong)))
  33 #define S390_THROWSTACK_ACCREGS         (S390_THROWSTACK_FLTREGS+(16*sizeof(gdouble)))
  34 #define S390_THROWSTACK_SIZE            (S390_THROWSTACK_ACCREGS+(16*sizeof(gint32)))
  35
  36 #define SZ_THROW        384
  37
  38 #define setup_context(ctx)
  39
  40 /*========================= End of Defines =========================*/
  41
  42 /*------------------------------------------------------------------*/
  43 /*                 I n c l u d e s                                  */
  44 /*------------------------------------------------------------------*/
  45
  46 #include <config.h>
  47 #include <glib.h>
  48 #include <signal.h>
  49 #include <string.h>
  50 #include <ucontext.h>
  51
  52 #include <mono/arch/s390x/s390x-codegen.h>
  53 #include <mono/metadata/appdomain.h>
  54 #include <mono/metadata/tabledefs.h>
  55 #include <mono/metadata/threads.h>
  56 #include <mono/metadata/debug-helpers.h>
  57 #include <mono/metadata/exception.h>
  58 #include <mono/metadata/mono-debug.h>
  59
  60 #include "mini.h"
  61 #include "mini-s390x.h"
  62 #include "support-s390x.h"
  63
  64 /*========================= End of Includes ========================*/
  65
  66 /*------------------------------------------------------------------*/
  67 /*                   P r o t o t y p e s                            */
  68 /*------------------------------------------------------------------*/
  69
  70 static void throw_exception (MonoObject *, unsigned long, unsigned long,
  71                  gulong *, gdouble *, gint32 *, guint, gboolean);
  72 static gpointer mono_arch_get_throw_exception_generic (int, MonoTrampInfo **,
  73                                 int, gboolean, gboolean);
  74 static void handle_signal_exception (gpointer);
  75
  76 /*========================= End of Prototypes ======================*/
  77
  78 /*------------------------------------------------------------------*/
  79 /*                 G l o b a l   V a r i a b l e s                  */
  80 /*------------------------------------------------------------------*/
  81
  82 typedef enum {
  83         by_none,
  84         by_token
  85 } throwType;
  86
  87 /*====================== End of Global Variables ===================*/
  88
  89 /*------------------------------------------------------------------*/
  90 /*                                                                  */
  91 /* Name         - mono_arch_get_call_filter                         */
  92 /*                                                                  */
  93 /* Function     - Return a pointer to a method which calls an       */
  94 /*                exception filter. We also use this function to    */
  95 /*                call finally handlers (we pass NULL as @exc       */
  96 /*                object in this case).                             */
  97 /*                                                                  */
  98 /*------------------------------------------------------------------*/
  99
 100 gpointer
 101 mono_arch_get_call_filter (MonoTrampInfo **info, gboolean aot)
 102 {
 103         static guint8 *start;
 104         static int inited = 0;
 105         guint8 *code;
 106         int alloc_size, pos, i;
 107         GSList *unwind_ops = NULL;
 108         MonoJumpInfo *ji = NULL;
 109
 110         g_assert (!aot);
 111
 112         if (inited)
 113                 return start;
 114
 115         inited = 1;
 116         /* call_filter (MonoContext *ctx, unsigned long eip, gpointer exc) */
 117         code = start = mono_global_codeman_reserve (512);
 118
 119         s390_stmg (code, s390_r6, s390_r14, STK_BASE, S390_REG_SAVE_OFFSET);
 120         s390_lgr  (code, s390_r14, STK_BASE);
 121         alloc_size = S390_ALIGN(S390_CALLFILTER_SIZE, S390_STACK_ALIGNMENT);
 122         s390_aghi (code, STK_BASE, -alloc_size);
 123         s390_stg  (code, s390_r14, 0, STK_BASE, 0);
 124
 125         /*------------------------------------------------------*/
 126         /* save general registers on stack                      */
 127         /*------------------------------------------------------*/
 128         s390_stmg (code, s390_r0, STK_BASE, STK_BASE, S390_CALLFILTER_INTREGS);
 129
 130         /*------------------------------------------------------*/
 131         /* save floating point registers on stack               */
 132         /*------------------------------------------------------*/
 133         pos = S390_CALLFILTER_FLTREGS;
 134         for (i = 0; i < 16; ++i) {
 135                 s390_std (code, i, 0, STK_BASE, pos);
 136                 pos += sizeof (gdouble);
 137         }
 138
 139         /*------------------------------------------------------*/
 140         /* save access registers on stack                       */
 141         /*------------------------------------------------------*/
 142         s390_stam (code, s390_a0, s390_a15, STK_BASE, S390_CALLFILTER_ACCREGS);
 143
 144         /*------------------------------------------------------*/
 145         /* Get A(Context)                                       */
 146         /*------------------------------------------------------*/
 147         s390_lgr  (code, s390_r13, s390_r2);
 148
 149         /*------------------------------------------------------*/
 150         /* Get A(Handler Entry Point)                           */
 151         /*------------------------------------------------------*/
 152         s390_lgr  (code, s390_r0, s390_r3);
 153
 154         /*------------------------------------------------------*/
 155         /* Set parameter register with Exception                */
 156         /*------------------------------------------------------*/
 157         s390_lgr  (code, s390_r2, s390_r4);
 158
 159         /*------------------------------------------------------*/
 160         /* Load all registers with values from the context      */
 161         /*------------------------------------------------------*/
 162         s390_lmg  (code, s390_r3, s390_r12, s390_r13,
 163                    G_STRUCT_OFFSET(MonoContext, uc_mcontext.gregs[3]));
 164         pos = G_STRUCT_OFFSET(MonoContext, uc_mcontext.fpregs.fprs[0]);
 165         for (i = 0; i < 16; ++i) {
 166                 s390_ld  (code, i, 0, s390_r13, pos);
 167                 pos += sizeof(gdouble);
 168         }
 169
 170 #if 0
 171         /*------------------------------------------------------*/
 172         /* We need to preserve current SP before calling filter */
 173         /* with SP from the context                             */
 174         /*------------------------------------------------------*/
 175         s390_lgr  (code, s390_r14, STK_BASE);
 176         s390_lg   (code, STK_BASE, 0, s390_r13,
 177                    G_STRUCT_OFFSET(MonoContext, uc_mcontext.gregs[15]));
 178         s390_lgr  (code, s390_r13, s390_r14);
 179 #endif
 180
 181         /*------------------------------------------------------*/
 182         /* Go call filter                                       */
 183         /*------------------------------------------------------*/
 184         s390_lgr  (code, s390_r1, s390_r0);
 185         s390_basr (code, s390_r14, s390_r1);
 186
 187         /*------------------------------------------------------*/
 188         /* Save return value                                    */
 189         /*------------------------------------------------------*/
 190         s390_lgr  (code, s390_r14, s390_r2);
 191
 192 #if 0
 193         /*------------------------------------------------------*/
 194         /* Reload our stack register with value saved in context*/
 195         /*------------------------------------------------------*/
 196         s390_lgr  (code, STK_BASE, s390_r13);
 197 #endif
 198
 199         /*------------------------------------------------------*/
 200         /* Restore all the regs from the stack                  */
 201         /*------------------------------------------------------*/
 202         s390_lmg  (code, s390_r0, s390_r13, STK_BASE, S390_CALLFILTER_INTREGS);
 203         pos = S390_CALLFILTER_FLTREGS;
 204         for (i = 0; i < 16; ++i) {
 205                 s390_ld (code, i, 0, STK_BASE, pos);
 206                 pos += sizeof (gdouble);
 207         }
 208
 209         s390_lgr  (code, s390_r2, s390_r14);
 210         s390_lam  (code, s390_a0, s390_a15, STK_BASE, S390_CALLFILTER_ACCREGS);
 211         s390_aghi (code, s390_r15, alloc_size);
 212         s390_lmg  (code, s390_r6, s390_r14, STK_BASE, S390_REG_SAVE_OFFSET);
 213         s390_br   (code, s390_r14);
 214
 215         g_assert ((code - start) < SZ_THROW);
 216
 217         mono_arch_flush_icache(start, code - start);
 218         MONO_PROFILER_RAISE (jit_code_buffer, (start, code - start, MONO_PROFILER_CODE_BUFFER_EXCEPTION_HANDLING, NULL));
 219
 220         if (info)
 221                 *info = mono_tramp_info_create ("call_filter",
 222                                                 start, code - start, ji,
 223                                                 unwind_ops);
 224
 225         return start;
 226 }
 227
 228 /*========================= End of Function ========================*/
 229
 230 /*------------------------------------------------------------------*/
 231 /*                                                                  */
 232 /* Name         - throw_exception.                                  */
 233 /*                                                                  */
 234 /* Function     - Raise an exception based on the parameters passed.*/
 235 /*                                                                  */
 236 /*------------------------------------------------------------------*/
 237
 238 static void
 239 throw_exception (MonoObject *exc, unsigned long ip, unsigned long sp,
 240                  gulong *int_regs, gdouble *fp_regs, gint32 *acc_regs,
 241                  guint fpc, gboolean rethrow)
 242 {
 243         MonoError error;
 244         MonoContext ctx;
 245         int iReg;
 246
 247         memset(&ctx, 0, sizeof(ctx));
 248
 249         setup_context(&ctx);
 250
 251         /* adjust eip so that it point into the call instruction */
 252         ip -= 2;
 253
 254         for (iReg = 0; iReg < 16; iReg++) {
 255                 ctx.uc_mcontext.gregs[iReg]         = int_regs[iReg];
 256                 ctx.uc_mcontext.fpregs.fprs[iReg].d = fp_regs[iReg];
 257                 ctx.uc_mcontext.aregs[iReg]         = acc_regs[iReg];
 258         }
 259
 260         ctx.uc_mcontext.fpregs.fpc = fpc;
 261
 262         MONO_CONTEXT_SET_BP (&ctx, sp);
 263         MONO_CONTEXT_SET_IP (&ctx, ip);
 264
 265         if (mono_object_isinst_checked (exc, mono_defaults.exception_class, &error)) {
 266                 MonoException *mono_ex = (MonoException*)exc;
 267                 if (!rethrow) {
 268                         mono_ex->stack_trace = NULL;
 269                         mono_ex->trace_ips = NULL;
 270                 }
 271         }
 272         mono_error_assert_ok (&error);
 273 //      mono_arch_handle_exception (&ctx, exc, FALSE);
 274         mono_handle_exception (&ctx, exc);
 275         mono_restore_context(&ctx);
 276
 277         g_assert_not_reached ();
 278 }
 279
 280 /*========================= End of Function ========================*/
 281
 282 /*------------------------------------------------------------------*/
 283 /*                                                                  */
 284 /* Name         - get_throw_exception_generic                       */
 285 /*                                                                  */
 286 /* Function     - Return a function pointer which can be used to    */
 287 /*                raise exceptions. The returned function has the   */
 288 /*                following signature:                              */
 289 /*                void (*func) (MonoException *exc); or,            */
 290 /*                void (*func) (char *exc_name);                    */
 291 /*                                                                  */
 292 /*------------------------------------------------------------------*/
 293
 294 static gpointer
 295 mono_arch_get_throw_exception_generic (int size, MonoTrampInfo **info,
 296                                 int corlib, gboolean rethrow, gboolean aot)
 297 {
 298         guint8 *code, *start;
 299         int alloc_size, pos, i;
 300         MonoJumpInfo *ji = NULL;
 301         GSList *unwind_ops = NULL;
 302
 303         code = start = mono_global_codeman_reserve(size);
 304
 305         s390_stmg (code, s390_r6, s390_r14, STK_BASE, S390_REG_SAVE_OFFSET);
 306         alloc_size = S390_ALIGN(S390_THROWSTACK_SIZE, S390_STACK_ALIGNMENT);
 307         s390_lgr  (code, s390_r14, STK_BASE);
 308         s390_aghi (code, STK_BASE, -alloc_size);
 309         s390_stg  (code, s390_r14, 0, STK_BASE, 0);
 310         s390_lgr  (code, s390_r3, s390_r2);
 311         if (corlib) {
 312                 S390_SET  (code, s390_r1, (guint8 *)mono_exception_from_token);
 313                 S390_SET  (code, s390_r2, (guint8 *)mono_defaults.exception_class->image);
 314                 s390_basr (code, s390_r14, s390_r1);
 315         }
 316
 317         /*------------------------------------------------------*/
 318         /* save the general registers on the stack              */
 319         /*------------------------------------------------------*/
 320         s390_stmg (code, s390_r0, s390_r13, STK_BASE, S390_THROWSTACK_INTREGS);
 321
 322         s390_lgr  (code, s390_r1, STK_BASE);
 323         s390_aghi (code, s390_r1, alloc_size);
 324         /*------------------------------------------------------*/
 325         /* save the return address in the parameter register    */
 326         /*------------------------------------------------------*/
 327         s390_lg   (code, s390_r3, 0, s390_r1, S390_RET_ADDR_OFFSET);
 328
 329         /*------------------------------------------------------*/
 330         /* save the floating point registers                    */
 331         /*------------------------------------------------------*/
 332         pos = S390_THROWSTACK_FLTREGS;
 333         for (i = 0; i < 16; ++i) {
 334                 s390_std (code, i, 0, STK_BASE, pos);
 335                 pos += sizeof (gdouble);
 336         }
 337         /*------------------------------------------------------*/
 338         /* save the access registers                            */
 339         /*------------------------------------------------------*/
 340         s390_stam (code, s390_r0, s390_r15, STK_BASE, S390_THROWSTACK_ACCREGS);
 341
 342         /*------------------------------------------------------*/
 343         /* call throw_exception (tkn, ip, sp, gr, fr, ar, re)   */
 344         /* - r2 already contains *exc                           */
 345         /*------------------------------------------------------*/
 346         s390_lgr  (code, s390_r4, s390_r1);        /* caller sp */
 347
 348         /*------------------------------------------------------*/
 349         /* pointer to the saved int regs                        */
 350         /*------------------------------------------------------*/
 351         s390_la   (code, s390_r5, 0, STK_BASE, S390_THROWSTACK_INTREGS);
 352         s390_la   (code, s390_r6, 0, STK_BASE, S390_THROWSTACK_FLTREGS);
 353         s390_la   (code, s390_r7, 0, STK_BASE, S390_THROWSTACK_ACCREGS);
 354         s390_stg  (code, s390_r7, 0, STK_BASE, S390_THROWSTACK_ACCPRM);
 355         s390_stfpc(code, STK_BASE, S390_THROWSTACK_FPCPRM+4);
 356         S390_SET  (code, s390_r1, (guint8 *)throw_exception);
 357         s390_lghi (code, s390_r7, rethrow);
 358         s390_stg  (code, s390_r7, 0, STK_BASE, S390_THROWSTACK_RETHROW);
 359         s390_basr (code, s390_r14, s390_r1);
 360         /* we should never reach this breakpoint */
 361         s390_break (code);
 362         g_assert ((code - start) < size);
 363
 364         mono_arch_flush_icache (start, code - start);
 365         MONO_PROFILER_RAISE (jit_code_buffer, (start, code - start, MONO_PROFILER_CODE_BUFFER_EXCEPTION_HANDLING, NULL));
 366
 367         if (info)
 368                 *info = mono_tramp_info_create (corlib ? "throw_corlib_exception"
 369                                                       : (rethrow ? "rethrow_exception"
 370                                                       : "throw_exception"),
 371                                                 start, code - start, ji, unwind_ops);
 372
 373         return start;
 374 }
 375
 376 /*========================= End of Function ========================*/
 377
 378 /*------------------------------------------------------------------*/
 379 /*                                                                  */
 380 /* Name         - arch_get_throw_exception                          */
 381 /*                                                                  */
 382 /* Function     - Return a function pointer which can be used to    */
 383 /*                raise exceptions. The returned function has the   */
 384 /*                following signature:                              */
 385 /*                void (*func) (MonoException *exc);                */
 386 /*                                                                  */
 387 /*------------------------------------------------------------------*/
 388
 389 gpointer
 390 mono_arch_get_throw_exception (MonoTrampInfo **info, gboolean aot)
 391 {
 392
 393         g_assert (!aot);
 394         if (info)
 395                 *info = NULL;
 396
 397         return (mono_arch_get_throw_exception_generic (SZ_THROW, info, FALSE, FALSE, aot));
 398 }
 399
 400 /*========================= End of Function ========================*/
 401
 402 /*------------------------------------------------------------------*/
 403 /*                                                                  */
 404 /* Name         - arch_get_rethrow_exception                        */
 405 /*                                                                  */
 406 /* Function     - Return a function pointer which can be used to    */
 407 /*                raise exceptions. The returned function has the   */
 408 /*                following signature:                              */
 409 /*                void (*func) (MonoException *exc);                */
 410 /*                                                                  */
 411 /*------------------------------------------------------------------*/
 412
 413 gpointer
 414 mono_arch_get_rethrow_exception (MonoTrampInfo **info, gboolean aot)
 415 {
 416         g_assert (!aot);
 417         if (info)
 418                 *info = NULL;
 419
 420         return (mono_arch_get_throw_exception_generic (SZ_THROW, info, FALSE, TRUE, aot));
 421 }
 422
 423 /*========================= End of Function ========================*/
 424
 425 /*------------------------------------------------------------------*/
 426 /*                                                                  */
 427 /* Name         - arch_get_corlib_exception                         */
 428 /*                                                                  */
 429 /* Function     - Return a function pointer which can be used to    */
 430 /*                raise corlib exceptions. The return function has  */
 431 /*                the following signature:                          */
 432 /*                void (*func) (guint32 token, guint32 offset)      */
 433 /*                                                                  */
 434 /*------------------------------------------------------------------*/
 435
 436 gpointer
 437 mono_arch_get_throw_corlib_exception (MonoTrampInfo **info, gboolean aot)
 438 {
 439         g_assert (!aot);
 440         if (info)
 441                 *info = NULL;
 442
 443         return (mono_arch_get_throw_exception_generic (SZ_THROW, info, TRUE, FALSE, aot));
 444 }
 445
 446 /*========================= End of Function ========================*/
 447
 448 /*------------------------------------------------------------------*/
 449 /*                                                                  */
 450 /* Name         - mono_arch_unwind_frame                           */
 451 /*                                                                  */
 452 /* Function     - See exceptions-amd64.c for docs.                  */
 453 /*                                                                  */
 454 /*------------------------------------------------------------------*/
 455
 456 gboolean
 457 mono_arch_unwind_frame (MonoDomain *domain, MonoJitTlsData *jit_tls,
 458                          MonoJitInfo *ji, MonoContext *ctx,
 459                          MonoContext *new_ctx, MonoLMF **lmf,
 460                          mgreg_t **save_locations,
 461                          StackFrameInfo *frame)
 462 {
 463         gpointer ip = (gpointer) MONO_CONTEXT_GET_IP (ctx);
 464
 465         memset (frame, 0, sizeof (StackFrameInfo));
 466         frame->ji = ji;
 467
 468         *new_ctx = *ctx;
 469
 470         if (ji != NULL) {
 471                 gint64 address;
 472                 guint8 *cfa;
 473                 guint32 unwind_info_len;
 474                 guint8 *unwind_info;
 475                 mgreg_t regs[16];
 476
 477                 if (ji->is_trampoline)
 478                         frame->type = FRAME_TYPE_TRAMPOLINE;
 479                 else
 480                         frame->type = FRAME_TYPE_MANAGED;
 481
 482                 unwind_info = mono_jinfo_get_unwind_info (ji, &unwind_info_len);
 483
 484                 address = (char *)ip - (char *)ji->code_start;
 485
 486                 memcpy(&regs, &ctx->uc_mcontext.gregs, sizeof(regs));
 487                 mono_unwind_frame (unwind_info, unwind_info_len, ji->code_start,
 488                                                    (guint8 *) ji->code_start + ji->code_size,
 489                                                    ip, NULL, regs, 16, save_locations,
 490                                                    MONO_MAX_IREGS, &cfa);
 491                 memcpy (&new_ctx->uc_mcontext.gregs, &regs, sizeof(regs));
 492                 MONO_CONTEXT_SET_IP(new_ctx, regs[14] - 2);
 493                 MONO_CONTEXT_SET_BP(new_ctx, cfa);
 494
 495                 return TRUE;
 496         } else if (*lmf) {
 497
 498                 ji = mini_jit_info_table_find (domain, (gpointer)(*lmf)->eip, NULL);
 499                 if (!ji) {
 500                         if (!(*lmf)->method)
 501                                 return FALSE;
 502
 503                         frame->method = (*lmf)->method;
 504                 }
 505
 506                 frame->ji = ji;
 507                 frame->type = FRAME_TYPE_MANAGED_TO_NATIVE;
 508
 509                 memcpy(new_ctx->uc_mcontext.gregs, (*lmf)->gregs, sizeof((*lmf)->gregs));
 510                 memcpy(new_ctx->uc_mcontext.fpregs.fprs, (*lmf)->fregs, sizeof((*lmf)->fregs));
 511                 MONO_CONTEXT_SET_BP (new_ctx, (*lmf)->ebp);
 512                 MONO_CONTEXT_SET_IP (new_ctx, (*lmf)->eip - 2);
 513                 *lmf = (*lmf)->previous_lmf;
 514
 515                 return TRUE;
 516         }
 517
 518         return FALSE;
 519 }
 520
 521 /*========================= End of Function ========================*/
 522
 523 /*------------------------------------------------------------------*/
 524 /*                                                                  */
 525 /* Name         - handle_signal_exception                           */
 526 /*                                                                  */
 527 /* Function     - Handle an exception raised by the JIT code.       */
 528 /*                                                                  */
 529 /* Parameters   - obj       - The exception object                  */
 530 /*                                                                  */
 531 /*------------------------------------------------------------------*/
 532
 533 static void
 534 handle_signal_exception (gpointer obj)
 535 {
 536         MonoJitTlsData *jit_tls = mono_tls_get_jit_tls ();
 537         MonoContext ctx;
 538
 539         memcpy (&ctx, &jit_tls->ex_ctx, sizeof (MonoContext));
 540         mono_handle_exception (&ctx, obj);
 541         mono_restore_context (&ctx);
 542 }
 543
 544 /*========================= End of Function ========================*/
 545
 546 /*------------------------------------------------------------------*/
 547 /*                                                                  */
 548 /* Name         - mono_arch_handle_exception                        */
 549 /*                                                                  */
 550 /* Function     - Handle an exception raised by the JIT code.       */
 551 /*                                                                  */
 552 /* Parameters   - ctx       - Saved processor state                 */
 553 /*                obj       - The exception object                  */
 554 /*                                                                  */
 555 /*------------------------------------------------------------------*/
 556
 557 gboolean
 558 mono_arch_handle_exception (void *sigctx, gpointer obj)
 559 {
 560         MonoContext mctx;
 561
 562         /*
 563          * Handling the exception in the signal handler is problematic, since the original
 564          * signal is disabled, and we could run arbitrary code though the debugger. So
 565          * resume into the normal stack and do most work there if possible.
 566          */
 567         MonoJitTlsData *jit_tls = mono_tls_get_jit_tls ();
 568
 569         /* Pass the ctx parameter in TLS */
 570         mono_sigctx_to_monoctx (sigctx, &jit_tls->ex_ctx);
 571
 572         mctx = jit_tls->ex_ctx;
 573         mono_arch_setup_async_callback (&mctx, handle_signal_exception, obj);
 574         mono_monoctx_to_sigctx (&mctx, sigctx);
 575
 576         return TRUE;
 577 }
 578
 579 /*========================= End of Function ========================*/
 580
 581 /*------------------------------------------------------------------*/
 582 /*                                                                  */
 583 /* Name         - mono_arch_setup_async_callback                    */
 584 /*                                                                  */
 585 /* Function     - Establish the async callback.                     */
 586 /*                                                                  */
 587 /* Parameters   - ctx       - Context                               */
 588 /*                async_cb  - Callback routine address              */
 589 /*                user_data - Data to be passed to callback         */
 590 /*                                                                  */
 591 /*------------------------------------------------------------------*/
 592
 593 void
 594 mono_arch_setup_async_callback (MonoContext *ctx, void (*async_cb)(void *fun), gpointer user_data)
 595 {
 596         uintptr_t sp = (uintptr_t) MONO_CONTEXT_GET_SP(ctx);
 597
 598         ctx->uc_mcontext.gregs[2] = (unsigned long) user_data;
 599
 600         sp -= S390_MINIMAL_STACK_SIZE;
 601         *(unsigned long *)sp = MONO_CONTEXT_GET_SP(ctx);
 602         MONO_CONTEXT_SET_BP(ctx, sp);
 603         MONO_CONTEXT_SET_IP(ctx, (unsigned long) async_cb);
 604 }
 605
 606 /*========================= End of Function ========================*/
 607
 608 /*------------------------------------------------------------------*/
 609 /*                                                                  */
 610 /* Name         - mono_arch_ip_from_context                         */
 611 /*                                                                  */
 612 /* Function     - Return the instruction pointer from the context.  */
 613 /*                                                                  */
 614 /* Parameters   - sigctx    - Saved processor state                 */
 615 /*                                                                  */
 616 /*------------------------------------------------------------------*/
 617
 618 gpointer
 619 mono_arch_ip_from_context (void *sigctx)
 620 {
 621         return ((gpointer) MONO_CONTEXT_GET_IP(((MonoContext *) sigctx)));
 622 }
 623
 624
 625 /*========================= End of Function ========================*/
 626
 627 /*------------------------------------------------------------------*/
 628 /*                                                                  */
 629 /* Name         - mono_arch_get_restore_context                    */
 630 /*                                                                  */
 631 /* Function     - Return the address of the routine that will rest- */
 632 /*                ore the context.                                  */
 633 /*                                                                  */
 634 /*------------------------------------------------------------------*/
 635
 636 gpointer
 637 mono_arch_get_restore_context (MonoTrampInfo **info, gboolean aot)
 638 {
 639         g_assert (!aot);
 640         if (info)
 641                 *info = NULL;
 642
 643         return setcontext;
 644 }
 645
 646 /*========================= End of Function ========================*/
 647
 648 /*------------------------------------------------------------------*/
 649 /*                                                                  */
 650 /* Name         - mono_arch_is_int_overflow                         */
 651 /*                                                                  */
 652 /* Function     - Inspect the code that raised the SIGFPE signal    */
 653 /*                to see if the DivideByZero or Arithmetic exception*/
 654 /*                should be raised.                                 */
 655 /*                                                                  */
 656 /*------------------------------------------------------------------*/
 657
 658 gboolean
 659 mono_arch_is_int_overflow (void *uc, void *info)
 660 {
 661         MonoContext *ctx;
 662         guint8      *code;
 663         guint64     *operand;
 664         gboolean    arithExc = TRUE;
 665         gint        regNo,
 666                     idxNo,
 667                     offset;
 668
 669         ctx  = (MonoContext *) uc;
 670         code =  (guint8 *) ((siginfo_t *)info)->si_addr;
 671         /*----------------------------------------------------------*/
 672         /* Divide operations are the only ones that will give the   */
 673         /* divide by zero exception so just check for these ops.    */
 674         /*----------------------------------------------------------*/
 675         switch (code[0]) {
 676                 case 0x1d :             /* Divide Register          */
 677                         regNo = code[1] & 0x0f;
 678                         if (ctx->uc_mcontext.gregs[regNo] == 0)
 679                                 arithExc = FALSE;
 680                 break;
 681                 case 0x5d :             /* Divide                   */
 682                         regNo   = (code[2] & 0xf0 >> 8);
 683                         idxNo   = (code[1] & 0x0f);
 684                         offset  = *((guint16 *) code+2) & 0x0fff;
 685                         operand = (guint64*)(ctx->uc_mcontext.gregs[regNo] + offset);
 686                         if (idxNo != 0)
 687                                 operand += ctx->uc_mcontext.gregs[idxNo];
 688                         if (*operand == 0)
 689                                 arithExc = FALSE;
 690                 break;
 691                 case 0xb9 :             /* DL[GR] or DS[GR]         */
 692                         if ((code[1] == 0x97) || (code[1] == 0x87) ||
 693                             (code[1] == 0x0d) || (code[1] == 0x1d)) {
 694                                 regNo = (code[3] & 0x0f);
 695                                 if (ctx->uc_mcontext.gregs[regNo] == 0)
 696                                         arithExc = FALSE;
 697                         }
 698                 break;
 699                 case 0xe3 :             /* DL[G] | DS[G]            */
 700                         if ((code[5] == 0x97) || (code[5] == 0x87) ||
 701                             (code[5] == 0x0d) || (code[5] == 0x1d)) {
 702                                 regNo   = (code[2] & 0xf0 >> 8);
 703                                 idxNo   = (code[1] & 0x0f);
 704                                 offset  = (code[2] & 0x0f << 8) +
 705                                           code[3] + (code[4] << 12);
 706                                 operand = (guint64*)(ctx->uc_mcontext.gregs[regNo] + offset);
 707                                 if (idxNo != 0)
 708                                         operand += ctx->uc_mcontext.gregs[idxNo];
 709                                 if (*operand == 0)
 710                                         arithExc = FALSE;
 711                         }
 712                 break;
 713                 default:
 714                         arithExc = TRUE;
 715         }
 716         ctx->uc_mcontext.psw.addr = (guint64)code;
 717         return (arithExc);
 718 }
 719
 720 /*========================= End of Function ========================*/