2 * exceptions-ppc.c: exception support for PowerPC
5 * Dietmar Maurer (dietmar@ximian.com)
6 * Paolo Molaro (lupus@ximian.com)
7 * Andreas Faerber <andreas.faerber@web.de>
9 * (C) 2001 Ximian, Inc.
10 * (C) 2007-2008 Andreas Faerber
22 #include <mono/arch/ppc/ppc-codegen.h>
23 #include <mono/metadata/appdomain.h>
24 #include <mono/metadata/tabledefs.h>
25 #include <mono/metadata/threads.h>
26 #include <mono/metadata/debug-helpers.h>
27 #include <mono/metadata/exception.h>
28 #include <mono/metadata/mono-debug.h>
36 int sc_onstack; // sigstack state to restore
37 int sc_mask; // signal mask to restore
39 int sc_psw; // processor status word
40 int sc_sp; // stack pointer if sc_regs == NULL
41 void *sc_regs; // (kernel private) saved state
46 sigset_t uc_sigmask; // signal mask used by this context
47 stack_t uc_stack; // stack used by this context
48 struct ucontext *uc_link; // pointer to resuming context
49 size_t uc_mcsize; // size of the machine context passed in
50 mcontext_t uc_mcontext; // machine specific context
53 typedef struct ppc_exception_state {
54 unsigned long dar; // Fault registers for coredump
56 unsigned long exception;// number of powerpc exception taken
57 unsigned long pad0; // align to 16 bytes
59 unsigned long pad1[4]; // space in PCB "just in case"
60 } ppc_exception_state_t;
62 typedef struct ppc_vector_state {
63 unsigned long save_vr[32][4];
64 unsigned long save_vscr[4];
65 unsigned int save_pad5[4];
66 unsigned int save_vrvalid; // VRs that have been saved
67 unsigned int save_pad6[7];
70 typedef struct ppc_float_state {
73 unsigned int fpscr_pad; // fpscr is 64 bits, 32 bits of rubbish
74 unsigned int fpscr; // floating point status register
77 typedef struct ppc_thread_state {
78 unsigned int srr0; // Instruction address register (PC)
79 unsigned int srr1; // Machine state register (supervisor)
85 unsigned int cr; // Condition register
86 unsigned int xer; // User's integer exception register
87 unsigned int lr; // Link register
88 unsigned int ctr; // Count register
89 unsigned int mq; // MQ register (601 only)
91 unsigned int vrsave; // Vector Save Register
95 ppc_exception_state_t es;
96 ppc_thread_state_t ss;
98 ppc_vector_state_t vs;
101 typedef struct mcontext * mcontext_t;
103 Linux/PPC instead has:
105 unsigned long _unused[4];
107 unsigned long handler;
108 unsigned long oldmask;
109 struct pt_regs *regs;
112 unsigned long gpr[32];
115 unsigned long orig_gpr3; // Used for restarting system calls
120 unsigned long mq; // 601 only (not used at present)
121 // Used on APUS to hold IPL value.
122 unsigned long trap; // Reason for being here
123 // N.B. for critical exceptions on 4xx, the dar and dsisr
124 // fields are overloaded to hold srr0 and srr1.
125 unsigned long dar; // Fault registers
126 unsigned long dsisr; // on 4xx/Book-E used for ESR
127 unsigned long result; // Result of a system call
130 elf_gregset_t mc_gregs;
131 elf_fpregset_t mc_fregs;
132 unsigned long mc_pad[2];
133 elf_vrregset_t mc_vregs __attribute__((__aligned__(16)));
137 unsigned long uc_flags;
138 struct ucontext *uc_link;
141 struct mcontext *uc_regs; // points to uc_mcontext field
143 // glibc has 1024-bit signal masks, ours are 64-bit
146 struct mcontext uc_mcontext;
149 #define ELF_NGREG 48 // includes nip, msr, lr, etc.
150 #define ELF_NFPREG 33 // includes fpscr
153 typedef unsigned long elf_greg_t;
154 typedef elf_greg_t elf_gregset_t[ELF_NGREG];
156 // Floating point registers
157 typedef double elf_fpreg_t;
158 typedef elf_fpreg_t elf_fpregset_t[ELF_NFPREG];
164 #define restore_regs_from_context(ctx_reg,ip_reg,tmp_reg) do { \
166 ppc_ldptr (code, ip_reg, G_STRUCT_OFFSET (MonoContext, sc_ir), ctx_reg); \
167 ppc_load_multiple_regs (code, ppc_r13, G_STRUCT_OFFSET (MonoContext, regs), ctx_reg); \
168 for (reg = 0; reg < MONO_SAVED_FREGS; ++reg) { \
169 ppc_lfd (code, (14 + reg), \
170 G_STRUCT_OFFSET(MonoContext, fregs) + reg * sizeof (gdouble), ctx_reg); \
175 #define setup_context(ctx)
177 #ifdef PPC_USES_FUNCTION_DESCRIPTOR
179 mono_ppc_create_pre_code_ftnptr (guint8 *code)
181 MonoPPCFunctionDescriptor *ftnptr = (MonoPPCFunctionDescriptor*)code;
183 code += sizeof (MonoPPCFunctionDescriptor);
193 * arch_get_restore_context:
195 * Returns a pointer to a method which restores a previously saved sigcontext.
196 * The first argument in r3 is the pointer to the context.
199 mono_arch_get_restore_context (MonoTrampInfo **info, gboolean aot)
201 guint8 *start, *code;
202 int size = MONO_PPC_32_64_CASE (128, 172) + PPC_FTNPTR_SIZE;
203 MonoJumpInfo *ji = NULL;
204 GSList *unwind_ops = NULL;
206 code = start = mono_global_codeman_reserve (size);
208 code = mono_ppc_create_pre_code_ftnptr (code);
209 restore_regs_from_context (ppc_r3, ppc_r4, ppc_r5);
210 /* restore also the stack pointer */
211 ppc_ldptr (code, ppc_sp, G_STRUCT_OFFSET (MonoContext, sc_sp), ppc_r3);
213 /* jump to the saved IP */
214 ppc_mtctr (code, ppc_r4);
215 ppc_bcctr (code, PPC_BR_ALWAYS, 0);
219 g_assert ((code - start) <= size);
220 mono_arch_flush_icache (start, code - start);
221 mono_profiler_code_buffer_new (start, code - start, MONO_PROFILER_CODE_BUFFER_EXCEPTION_HANDLING, NULL);
224 *info = mono_tramp_info_create ("restore_context", start, code - start, ji, unwind_ops);
229 #define SAVED_REGS_LENGTH (sizeof (gdouble) * MONO_SAVED_FREGS + sizeof (gpointer) * MONO_SAVED_GREGS)
230 #define ALIGN_STACK_FRAME_SIZE(s) (((s) + MONO_ARCH_FRAME_ALIGNMENT - 1) & ~(MONO_ARCH_FRAME_ALIGNMENT - 1))
231 /* The 64 bytes here are for outgoing arguments and a bit of spare.
232 We don't use it all, but it doesn't hurt. */
233 #define REG_SAVE_STACK_FRAME_SIZE (ALIGN_STACK_FRAME_SIZE (SAVED_REGS_LENGTH + PPC_MINIMAL_STACK_SIZE + 64))
236 emit_save_saved_regs (guint8 *code, int pos)
240 for (i = 31; i >= 14; --i) {
241 pos -= sizeof (gdouble);
242 ppc_stfd (code, i, pos, ppc_sp);
244 pos -= sizeof (gpointer) * MONO_SAVED_GREGS;
245 ppc_store_multiple_regs (code, ppc_r13, pos, ppc_sp);
251 * mono_arch_get_call_filter:
253 * Returns a pointer to a method which calls an exception filter. We
254 * also use this function to call finally handlers (we pass NULL as
255 * @exc object in this case).
258 mono_arch_get_call_filter (MonoTrampInfo **info, gboolean aot)
260 guint8 *start, *code;
261 int alloc_size, pos, i;
262 int size = MONO_PPC_32_64_CASE (320, 500) + PPC_FTNPTR_SIZE;
263 MonoJumpInfo *ji = NULL;
264 GSList *unwind_ops = NULL;
266 /* call_filter (MonoContext *ctx, unsigned long eip, gpointer exc) */
267 code = start = mono_global_codeman_reserve (size);
269 code = mono_ppc_create_pre_code_ftnptr (code);
272 ppc_mflr (code, ppc_r0);
273 ppc_stptr (code, ppc_r0, PPC_RET_ADDR_OFFSET, ppc_sp);
275 alloc_size = REG_SAVE_STACK_FRAME_SIZE;
277 /* allocate stack frame and set link from sp in ctx */
278 g_assert ((alloc_size & (MONO_ARCH_FRAME_ALIGNMENT-1)) == 0);
279 ppc_ldptr (code, ppc_r0, G_STRUCT_OFFSET (MonoContext, sc_sp), ppc_r3);
280 ppc_ldptr_indexed (code, ppc_r0, ppc_r0, ppc_r0);
281 ppc_stptr_update (code, ppc_r0, -alloc_size, ppc_sp);
283 code = emit_save_saved_regs (code, alloc_size);
285 /* restore all the regs from ctx (in r3), but not r1, the stack pointer */
286 restore_regs_from_context (ppc_r3, ppc_r6, ppc_r7);
287 /* call handler at eip (r4) and set the first arg with the exception (r5) */
288 ppc_mtctr (code, ppc_r4);
289 ppc_mr (code, ppc_r3, ppc_r5);
290 ppc_bcctrl (code, PPC_BR_ALWAYS, 0);
293 ppc_ldptr (code, ppc_r0, alloc_size + PPC_RET_ADDR_OFFSET, ppc_sp);
294 ppc_mtlr (code, ppc_r0);
296 /* restore all the regs from the stack */
298 for (i = 31; i >= 14; --i) {
299 pos -= sizeof (gdouble);
300 ppc_lfd (code, i, pos, ppc_sp);
302 pos -= sizeof (gpointer) * MONO_SAVED_GREGS;
303 ppc_load_multiple_regs (code, ppc_r13, pos, ppc_sp);
305 ppc_addic (code, ppc_sp, ppc_sp, alloc_size);
308 g_assert ((code - start) < size);
309 mono_arch_flush_icache (start, code - start);
310 mono_profiler_code_buffer_new (start, code - start, MONO_PROFILER_CODE_BUFFER_EXCEPTION_HANDLING, NULL);
313 *info = mono_tramp_info_create ("call_filter", start, code - start, ji, unwind_ops);
319 mono_ppc_throw_exception (MonoObject *exc, unsigned long eip, unsigned long esp, mgreg_t *int_regs, gdouble *fp_regs, gboolean rethrow)
323 /* adjust eip so that it point into the call instruction */
326 setup_context (&ctx);
328 /*printf ("stack in throw: %p\n", esp);*/
329 MONO_CONTEXT_SET_BP (&ctx, esp);
330 MONO_CONTEXT_SET_IP (&ctx, eip);
331 memcpy (&ctx.regs, int_regs, sizeof (mgreg_t) * MONO_SAVED_GREGS);
332 memcpy (&ctx.fregs, fp_regs, sizeof (double) * MONO_SAVED_FREGS);
334 if (mono_object_isinst (exc, mono_defaults.exception_class)) {
335 MonoException *mono_ex = (MonoException*)exc;
337 mono_ex->stack_trace = NULL;
339 mono_handle_exception (&ctx, exc);
340 mono_restore_context (&ctx);
342 g_assert_not_reached ();
346 * arch_get_throw_exception_generic:
348 * Returns a function pointer which can be used to raise
349 * exceptions. The returned function has the following
350 * signature: void (*func) (MonoException *exc); or
351 * void (*func) (guint32 ex_token, gpointer ip)
355 mono_arch_get_throw_exception_generic (int size, MonoTrampInfo **info, int corlib, gboolean rethrow, gboolean aot)
357 guint8 *start, *code;
359 MonoJumpInfo *ji = NULL;
360 GSList *unwind_ops = NULL;
362 code = start = mono_global_codeman_reserve (size);
364 code = mono_ppc_create_pre_code_ftnptr (code);
368 ppc_mr (code, ppc_r0, ppc_r4);
370 ppc_mflr (code, ppc_r0);
371 ppc_stptr (code, ppc_r0, PPC_RET_ADDR_OFFSET, ppc_sp);
373 alloc_size = REG_SAVE_STACK_FRAME_SIZE;
375 g_assert ((alloc_size & (MONO_ARCH_FRAME_ALIGNMENT-1)) == 0);
376 ppc_stptr_update (code, ppc_sp, -alloc_size, ppc_sp);
378 code = emit_save_saved_regs (code, alloc_size);
382 ppc_mr (code, ppc_r4, ppc_r3);
385 code = mono_arch_emit_load_aotconst (start, code, &ji, MONO_PATCH_INFO_IMAGE, mono_defaults.corlib);
386 ppc_mr (code, ppc_r3, ppc_r12);
387 code = mono_arch_emit_load_aotconst (start, code, &ji, MONO_PATCH_INFO_JIT_ICALL_ADDR, "mono_exception_from_token");
388 #ifdef PPC_USES_FUNCTION_DESCRIPTOR
389 ppc_ldptr (code, ppc_r2, sizeof (gpointer), ppc_r12);
390 ppc_ldptr (code, ppc_r12, 0, ppc_r12);
392 ppc_mtctr (code, ppc_r12);
393 ppc_bcctrl (code, PPC_BR_ALWAYS, 0);
395 ppc_load (code, ppc_r3, (gulong)mono_defaults.corlib);
396 ppc_load_func (code, PPC_CALL_REG, mono_exception_from_token);
397 ppc_mtctr (code, PPC_CALL_REG);
398 ppc_bcctrl (code, PPC_BR_ALWAYS, 0);
402 /* call throw_exception (exc, ip, sp, int_regs, fp_regs) */
404 ppc_ldptr (code, ppc_r5, 0, ppc_sp);
405 /* exc is already in place in r3 */
407 ppc_ldptr (code, ppc_r4, PPC_RET_ADDR_OFFSET, ppc_r5);
409 ppc_mr (code, ppc_r4, ppc_r0); /* caller ip */
410 /* pointer to the saved fp regs */
411 pos = alloc_size - sizeof (gdouble) * MONO_SAVED_FREGS;
412 ppc_addi (code, ppc_r7, ppc_sp, pos);
413 /* pointer to the saved int regs */
414 pos -= sizeof (gpointer) * MONO_SAVED_GREGS;
415 ppc_addi (code, ppc_r6, ppc_sp, pos);
416 ppc_li (code, ppc_r8, rethrow);
419 // This can be called from runtime code, which can't guarantee that
420 // r30 contains the got address.
421 // So emit the got address loading code too
422 code = mono_arch_emit_load_got_addr (start, code, NULL, &ji);
423 code = mono_arch_emit_load_aotconst (start, code, &ji, MONO_PATCH_INFO_JIT_ICALL_ADDR, "mono_ppc_throw_exception");
424 #ifdef PPC_USES_FUNCTION_DESCRIPTOR
425 ppc_ldptr (code, ppc_r2, sizeof (gpointer), ppc_r12);
426 ppc_ldptr (code, ppc_r12, 0, ppc_r12);
428 ppc_mtctr (code, ppc_r12);
429 ppc_bcctrl (code, PPC_BR_ALWAYS, 0);
431 ppc_load_func (code, PPC_CALL_REG, mono_ppc_throw_exception);
432 ppc_mtctr (code, PPC_CALL_REG);
433 ppc_bcctrl (code, PPC_BR_ALWAYS, 0);
435 /* we should never reach this breakpoint */
437 g_assert ((code - start) <= size);
438 mono_arch_flush_icache (start, code - start);
439 mono_profiler_code_buffer_new (start, code - start, MONO_PROFILER_CODE_BUFFER_EXCEPTION_HANDLING, NULL);
442 *info = mono_tramp_info_create (corlib ? "throw_corlib_exception" : (rethrow ? "rethrow_exception" : "throw_exception"), start, code - start, ji, unwind_ops);
448 * mono_arch_get_rethrow_exception:
450 * Returns a function pointer which can be used to rethrow
451 * exceptions. The returned function has the following
452 * signature: void (*func) (MonoException *exc);
456 mono_arch_get_rethrow_exception (MonoTrampInfo **info, gboolean aot)
458 int size = MONO_PPC_32_64_CASE (132, 224) + PPC_FTNPTR_SIZE;
462 return mono_arch_get_throw_exception_generic (size, info, FALSE, TRUE, aot);
466 * arch_get_throw_exception:
468 * Returns a function pointer which can be used to raise
469 * exceptions. The returned function has the following
470 * signature: void (*func) (MonoException *exc);
471 * For example to raise an arithmetic exception you can use:
473 * x86_push_imm (code, mono_get_exception_arithmetic ());
474 * x86_call_code (code, arch_get_throw_exception ());
478 mono_arch_get_throw_exception (MonoTrampInfo **info, gboolean aot)
480 int size = MONO_PPC_32_64_CASE (132, 224) + PPC_FTNPTR_SIZE;
484 return mono_arch_get_throw_exception_generic (size, info, FALSE, FALSE, aot);
488 * mono_arch_get_throw_corlib_exception:
490 * Returns a function pointer which can be used to raise
491 * corlib exceptions. The returned function has the following
492 * signature: void (*func) (guint32 ex_token, guint32 offset);
493 * On PPC, we pass the ip instead of the offset
496 mono_arch_get_throw_corlib_exception (MonoTrampInfo **info, gboolean aot)
498 int size = MONO_PPC_32_64_CASE (168, 304) + PPC_FTNPTR_SIZE;
502 return mono_arch_get_throw_exception_generic (size, info, TRUE, FALSE, aot);
506 * mono_arch_find_jit_info:
508 * See exceptions-amd64.c for docs.
511 mono_arch_find_jit_info (MonoDomain *domain, MonoJitTlsData *jit_tls,
512 MonoJitInfo *ji, MonoContext *ctx,
513 MonoContext *new_ctx, MonoLMF **lmf,
514 mgreg_t **save_locations,
515 StackFrameInfo *frame)
517 gpointer ip = MONO_CONTEXT_GET_IP (ctx);
518 MonoPPCStackFrame *sframe;
520 memset (frame, 0, sizeof (StackFrameInfo));
524 setup_context (new_ctx);
528 mgreg_t regs [ppc_lr + 1];
530 guint32 unwind_info_len;
533 frame->type = FRAME_TYPE_MANAGED;
535 unwind_info = mono_jinfo_get_unwind_info (ji, &unwind_info_len);
537 sframe = (MonoPPCStackFrame*)MONO_CONTEXT_GET_SP (ctx);
538 MONO_CONTEXT_SET_BP (new_ctx, sframe->sp);
539 if (jinfo_get_method (ji)->save_lmf) {
540 /* sframe->sp points just past the end of the LMF */
541 guint8 *lmf_addr = (guint8*)sframe->sp - sizeof (MonoLMF);
542 memcpy (&new_ctx->fregs, lmf_addr + G_STRUCT_OFFSET (MonoLMF, fregs), sizeof (double) * MONO_SAVED_FREGS);
543 memcpy (&new_ctx->regs, lmf_addr + G_STRUCT_OFFSET (MonoLMF, iregs), sizeof (mgreg_t) * MONO_SAVED_GREGS);
544 /* the calling IP is in the parent frame */
545 sframe = (MonoPPCStackFrame*)sframe->sp;
546 /* we substract 4, so that the IP points into the call instruction */
547 MONO_CONTEXT_SET_IP (new_ctx, sframe->lr - 4);
549 regs [ppc_lr] = ctx->sc_ir;
550 regs [ppc_sp] = ctx->sc_sp;
551 for (i = 0; i < MONO_SAVED_GREGS; ++i)
552 regs [ppc_r13 + i] = ctx->regs [i];
554 mono_unwind_frame (unwind_info, unwind_info_len, ji->code_start,
555 (guint8*)ji->code_start + ji->code_size,
556 ip, NULL, regs, ppc_lr + 1,
557 save_locations, MONO_MAX_IREGS, &cfa);
559 /* we substract 4, so that the IP points into the call instruction */
560 MONO_CONTEXT_SET_IP (new_ctx, regs [ppc_lr] - 4);
561 MONO_CONTEXT_SET_BP (new_ctx, cfa);
563 for (i = 0; i < MONO_SAVED_GREGS; ++i)
564 new_ctx->regs [i] = regs [ppc_r13 + i];
570 if ((ji = mini_jit_info_table_find (domain, (gpointer)(*lmf)->eip, NULL))) {
575 /* Trampoline lmf frame */
576 frame->method = (*lmf)->method;
579 /*sframe = (MonoPPCStackFrame*)MONO_CONTEXT_GET_SP (ctx);
580 MONO_CONTEXT_SET_BP (new_ctx, sframe->sp);
581 MONO_CONTEXT_SET_IP (new_ctx, sframe->lr);*/
582 MONO_CONTEXT_SET_BP (new_ctx, (*lmf)->ebp);
583 MONO_CONTEXT_SET_IP (new_ctx, (*lmf)->eip);
584 memcpy (&new_ctx->regs, (*lmf)->iregs, sizeof (mgreg_t) * MONO_SAVED_GREGS);
585 memcpy (&new_ctx->fregs, (*lmf)->fregs, sizeof (double) * MONO_SAVED_FREGS);
588 frame->type = FRAME_TYPE_MANAGED_TO_NATIVE;
590 /* FIXME: what about trampoline LMF frames? see exceptions-x86.c */
592 *lmf = (*lmf)->previous_lmf;
601 mono_arch_ip_from_context (void *sigctx)
603 #ifdef MONO_CROSS_COMPILE
604 g_assert_not_reached ();
606 os_ucontext *uc = sigctx;
607 return (gpointer)UCONTEXT_REG_NIP(uc);
612 mono_ppc_set_func_into_sigctx (void *sigctx, void *func)
614 #ifdef MONO_CROSS_COMPILE
615 g_assert_not_reached ();
616 #elif defined(PPC_USES_FUNCTION_DESCRIPTOR)
617 /* Have to set both the ip and the TOC reg */
618 os_ucontext *uc = sigctx;
620 UCONTEXT_REG_NIP(uc) = ((gsize*)func) [0];
621 UCONTEXT_REG_Rn (uc, 2) = ((gsize*)func)[1];
623 g_assert_not_reached ();
628 altstack_handle_and_restore (void *sigctx, gpointer obj)
632 mono_sigctx_to_monoctx (sigctx, &mctx);
633 mono_handle_exception (&mctx, obj);
634 mono_restore_context (&mctx);
638 mono_arch_handle_altstack_exception (void *sigctx, MONO_SIG_HANDLER_INFO_TYPE *siginfo, gpointer fault_addr, gboolean stack_ovf)
640 #ifdef MONO_CROSS_COMPILE
641 g_assert_not_reached ();
643 #ifdef MONO_ARCH_USE_SIGACTION
644 os_ucontext *uc = (ucontext_t*)sigctx;
645 os_ucontext *uc_copy;
646 MonoJitInfo *ji = mini_jit_info_table_find (mono_domain_get (), mono_arch_ip_from_context (sigctx), NULL);
652 /* we don't do much now, but we can warn the user with a useful message */
653 fprintf (stderr, "Stack overflow: IP: %p, SP: %p\n", mono_arch_ip_from_context (sigctx), (gpointer)UCONTEXT_REG_Rn(uc, 1));
654 if (ji && jinfo_get_method (ji))
655 method = mono_method_full_name (jinfo_get_method (ji), TRUE);
657 method = "Unmanaged";
658 fprintf (stderr, "At %s\n", method);
662 mono_handle_native_sigsegv (SIGSEGV, sigctx, siginfo);
663 /* setup a call frame on the real stack so that control is returned there
664 * and exception handling can continue.
665 * The frame looks like:
668 * 224 is the size of the red zone
670 frame_size = sizeof (ucontext_t) + sizeof (gpointer) * 16 + 224;
673 sp = (gpointer)(UCONTEXT_REG_Rn(uc, 1) & ~15);
674 sp = (gpointer)((char*)sp - frame_size);
675 /* may need to adjust pointers in the new struct copy, depending on the OS */
676 uc_copy = (ucontext_t*)(sp + 16);
677 memcpy (uc_copy, uc, sizeof (os_ucontext));
678 #if defined(__linux__) && !defined(__mono_ppc64__)
679 uc_copy->uc_mcontext.uc_regs = (gpointer)((char*)uc_copy + ((char*)uc->uc_mcontext.uc_regs - (char*)uc));
681 g_assert (mono_arch_ip_from_context (uc) == mono_arch_ip_from_context (uc_copy));
682 /* at the return form the signal handler execution starts in altstack_handle_and_restore() */
683 UCONTEXT_REG_LNK(uc) = UCONTEXT_REG_NIP(uc);
684 #ifdef PPC_USES_FUNCTION_DESCRIPTOR
686 MonoPPCFunctionDescriptor *handler_ftnptr = (MonoPPCFunctionDescriptor*)altstack_handle_and_restore;
688 UCONTEXT_REG_NIP(uc) = (gulong)handler_ftnptr->code;
689 UCONTEXT_REG_Rn(uc, 2) = (gulong)handler_ftnptr->toc;
692 UCONTEXT_REG_NIP(uc) = (unsigned long)altstack_handle_and_restore;
694 UCONTEXT_REG_Rn(uc, 1) = (unsigned long)sp;
695 UCONTEXT_REG_Rn(uc, PPC_FIRST_ARG_REG) = (unsigned long)(sp + 16);
696 UCONTEXT_REG_Rn(uc, PPC_FIRST_ARG_REG + 1) = 0;
697 UCONTEXT_REG_Rn(uc, PPC_FIRST_ARG_REG + 2) = 0;
700 #endif /* !MONO_CROSS_COMPILE */
706 * Called by resuming from a signal handler.
709 handle_signal_exception (gpointer obj)
711 MonoJitTlsData *jit_tls = mono_native_tls_get_value (mono_jit_tls_id);
714 memcpy (&ctx, &jit_tls->ex_ctx, sizeof (MonoContext));
716 mono_handle_exception (&ctx, obj);
718 mono_restore_context (&ctx);
722 setup_ucontext_return (void *uc, gpointer func)
724 #if !defined(MONO_CROSS_COMPILE)
725 UCONTEXT_REG_LNK(uc) = UCONTEXT_REG_NIP(uc);
726 #ifdef PPC_USES_FUNCTION_DESCRIPTOR
728 MonoPPCFunctionDescriptor *handler_ftnptr = (MonoPPCFunctionDescriptor*)func;
730 UCONTEXT_REG_NIP(uc) = (gulong)handler_ftnptr->code;
731 UCONTEXT_REG_Rn(uc, 2) = (gulong)handler_ftnptr->toc;
734 UCONTEXT_REG_NIP(uc) = (unsigned long)func;
740 mono_arch_handle_exception (void *ctx, gpointer obj)
742 #if defined(MONO_ARCH_USE_SIGACTION) && defined(UCONTEXT_REG_Rn)
744 * Handling the exception in the signal handler is problematic, since the original
745 * signal is disabled, and we could run arbitrary code though the debugger. So
746 * resume into the normal stack and do most work there if possible.
748 MonoJitTlsData *jit_tls = mono_native_tls_get_value (mono_jit_tls_id);
754 /* Pass the ctx parameter in TLS */
755 mono_sigctx_to_monoctx (sigctx, &jit_tls->ex_ctx);
756 /* The others in registers */
757 UCONTEXT_REG_Rn (sigctx, PPC_FIRST_ARG_REG) = (gsize)obj;
759 /* Allocate a stack frame below the red zone */
760 /* Similar to mono_arch_handle_altstack_exception () */
764 sp = (mgreg_t)(UCONTEXT_REG_Rn(uc, 1) & ~15);
765 sp = (mgreg_t)(sp - frame_size);
766 UCONTEXT_REG_Rn(uc, 1) = (mgreg_t)sp;
767 setup_ucontext_return (uc, handle_signal_exception);
774 mono_sigctx_to_monoctx (ctx, &mctx);
776 result = mono_handle_exception (&mctx, obj);
777 /* restore the context so that returning from the signal handler will invoke
780 mono_monoctx_to_sigctx (&mctx, ctx);