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_full (guint32 *code_size, MonoJumpInfo **ji, gboolean aot)
201 guint8 *start, *code;
202 int size = MONO_PPC_32_64_CASE (128, 172) + PPC_FTNPTR_SIZE;
204 code = start = mono_global_codeman_reserve (size);
207 code = mono_ppc_create_pre_code_ftnptr (code);
208 restore_regs_from_context (ppc_r3, ppc_r4, ppc_r5);
209 /* restore also the stack pointer */
210 ppc_ldptr (code, ppc_sp, G_STRUCT_OFFSET (MonoContext, sc_sp), ppc_r3);
212 /* jump to the saved IP */
213 ppc_mtctr (code, ppc_r4);
214 ppc_bcctr (code, PPC_BR_ALWAYS, 0);
218 g_assert ((code - start) <= size);
219 mono_arch_flush_icache (start, code - start);
221 *code_size = code - start;
226 #define SAVED_REGS_LENGTH (sizeof (gdouble) * MONO_SAVED_FREGS + sizeof (gpointer) * MONO_SAVED_GREGS)
227 #define ALIGN_STACK_FRAME_SIZE(s) (((s) + MONO_ARCH_FRAME_ALIGNMENT - 1) & ~(MONO_ARCH_FRAME_ALIGNMENT - 1))
228 /* The 64 bytes here are for outgoing arguments and a bit of spare.
229 We don't use it all, but it doesn't hurt. */
230 #define REG_SAVE_STACK_FRAME_SIZE (ALIGN_STACK_FRAME_SIZE (SAVED_REGS_LENGTH + PPC_MINIMAL_STACK_SIZE + 64))
233 emit_save_saved_regs (guint8 *code, int pos)
237 for (i = 31; i >= 14; --i) {
238 pos -= sizeof (gdouble);
239 ppc_stfd (code, i, pos, ppc_sp);
241 pos -= sizeof (gpointer) * MONO_SAVED_GREGS;
242 ppc_store_multiple_regs (code, ppc_r13, pos, ppc_sp);
248 * mono_arch_get_call_filter:
250 * Returns a pointer to a method which calls an exception filter. We
251 * also use this function to call finally handlers (we pass NULL as
252 * @exc object in this case).
255 mono_arch_get_call_filter_full (guint32 *code_size, MonoJumpInfo **ji, gboolean aot)
257 guint8 *start, *code;
258 int alloc_size, pos, i;
259 int size = MONO_PPC_32_64_CASE (320, 500) + PPC_FTNPTR_SIZE;
263 /* call_filter (MonoContext *ctx, unsigned long eip, gpointer exc) */
264 code = start = mono_global_codeman_reserve (size);
266 code = mono_ppc_create_pre_code_ftnptr (code);
269 ppc_mflr (code, ppc_r0);
270 ppc_stptr (code, ppc_r0, PPC_RET_ADDR_OFFSET, ppc_sp);
272 alloc_size = REG_SAVE_STACK_FRAME_SIZE;
274 /* allocate stack frame and set link from sp in ctx */
275 g_assert ((alloc_size & (MONO_ARCH_FRAME_ALIGNMENT-1)) == 0);
276 ppc_ldptr (code, ppc_r0, G_STRUCT_OFFSET (MonoContext, sc_sp), ppc_r3);
277 ppc_ldptr_indexed (code, ppc_r0, ppc_r0, ppc_r0);
278 ppc_stptr_update (code, ppc_r0, -alloc_size, ppc_sp);
280 code = emit_save_saved_regs (code, alloc_size);
282 /* restore all the regs from ctx (in r3), but not r1, the stack pointer */
283 restore_regs_from_context (ppc_r3, ppc_r6, ppc_r7);
284 /* call handler at eip (r4) and set the first arg with the exception (r5) */
285 ppc_mtctr (code, ppc_r4);
286 ppc_mr (code, ppc_r3, ppc_r5);
287 ppc_bcctrl (code, PPC_BR_ALWAYS, 0);
290 ppc_ldptr (code, ppc_r0, alloc_size + PPC_RET_ADDR_OFFSET, ppc_sp);
291 ppc_mtlr (code, ppc_r0);
293 /* restore all the regs from the stack */
295 for (i = 31; i >= 14; --i) {
296 pos -= sizeof (gdouble);
297 ppc_lfd (code, i, pos, ppc_sp);
299 pos -= sizeof (gpointer) * MONO_SAVED_GREGS;
300 ppc_load_multiple_regs (code, ppc_r13, pos, ppc_sp);
302 ppc_addic (code, ppc_sp, ppc_sp, alloc_size);
305 g_assert ((code - start) < size);
306 mono_arch_flush_icache (start, code - start);
308 *code_size = code - start;
314 mono_ppc_throw_exception (MonoObject *exc, unsigned long eip, unsigned long esp, gulong *int_regs, gdouble *fp_regs, gboolean rethrow)
316 static void (*restore_context) (MonoContext *);
319 if (!restore_context)
320 restore_context = mono_get_restore_context ();
322 /* adjust eip so that it point into the call instruction */
325 setup_context (&ctx);
327 /*printf ("stack in throw: %p\n", esp);*/
328 MONO_CONTEXT_SET_BP (&ctx, esp);
329 MONO_CONTEXT_SET_IP (&ctx, eip);
330 memcpy (&ctx.regs, int_regs, sizeof (gulong) * MONO_SAVED_GREGS);
331 memcpy (&ctx.fregs, fp_regs, sizeof (double) * MONO_SAVED_FREGS);
333 if (mono_object_isinst (exc, mono_defaults.exception_class)) {
334 MonoException *mono_ex = (MonoException*)exc;
336 mono_ex->stack_trace = NULL;
338 mono_handle_exception (&ctx, exc, (gpointer)eip, FALSE);
339 restore_context (&ctx);
341 g_assert_not_reached ();
345 * arch_get_throw_exception_generic:
347 * Returns a function pointer which can be used to raise
348 * exceptions. The returned function has the following
349 * signature: void (*func) (MonoException *exc); or
350 * void (*func) (guint32 ex_token, gpointer ip)
354 mono_arch_get_throw_exception_generic (int size, guint32 *code_size, MonoJumpInfo **ji, int corlib, gboolean rethrow, gboolean aot)
356 guint8 *start, *code;
361 code = start = mono_global_codeman_reserve (size);
363 code = mono_ppc_create_pre_code_ftnptr (code);
367 ppc_mr (code, ppc_r0, ppc_r4);
369 ppc_mflr (code, ppc_r0);
370 ppc_stptr (code, ppc_r0, PPC_RET_ADDR_OFFSET, ppc_sp);
372 alloc_size = REG_SAVE_STACK_FRAME_SIZE;
374 g_assert ((alloc_size & (MONO_ARCH_FRAME_ALIGNMENT-1)) == 0);
375 ppc_stptr_update (code, ppc_sp, -alloc_size, ppc_sp);
377 code = emit_save_saved_regs (code, alloc_size);
381 ppc_mr (code, ppc_r4, ppc_r3);
384 code = mono_arch_emit_load_aotconst (start, code, ji, MONO_PATCH_INFO_IMAGE, mono_defaults.corlib);
385 ppc_mr (code, ppc_r3, ppc_r11);
386 code = mono_arch_emit_load_aotconst (start, code, ji, MONO_PATCH_INFO_JIT_ICALL_ADDR, "mono_exception_from_token");
387 #ifdef PPC_USES_FUNCTION_DESCRIPTOR
388 ppc_ldptr (code, ppc_r2, sizeof (gpointer), ppc_r11);
389 ppc_ldptr (code, ppc_r11, 0, ppc_r11);
391 ppc_mtctr (code, ppc_r11);
392 ppc_bcctrl (code, PPC_BR_ALWAYS, 0);
394 ppc_load (code, ppc_r3, (gulong)mono_defaults.corlib);
395 ppc_load_func (code, ppc_r0, mono_exception_from_token);
396 ppc_mtctr (code, ppc_r0);
397 ppc_bcctrl (code, PPC_BR_ALWAYS, 0);
401 /* call throw_exception (exc, ip, sp, int_regs, fp_regs) */
403 ppc_ldptr (code, ppc_r5, 0, ppc_sp);
404 /* exc is already in place in r3 */
406 ppc_ldptr (code, ppc_r4, PPC_RET_ADDR_OFFSET, ppc_r5);
408 ppc_mr (code, ppc_r4, ppc_r0); /* caller ip */
409 /* pointer to the saved fp regs */
410 pos = alloc_size - sizeof (gdouble) * MONO_SAVED_FREGS;
411 ppc_addi (code, ppc_r7, ppc_sp, pos);
412 /* pointer to the saved int regs */
413 pos -= sizeof (gpointer) * MONO_SAVED_GREGS;
414 ppc_addi (code, ppc_r6, ppc_sp, pos);
415 ppc_li (code, ppc_r8, rethrow);
418 // This can be called from runtime code, which can't guarantee that
419 // r30 contains the got address.
420 // So emit the got address loading code too
421 code = mono_arch_emit_load_got_addr (start, code, NULL, ji);
422 code = mono_arch_emit_load_aotconst (start, code, ji, MONO_PATCH_INFO_JIT_ICALL_ADDR, "mono_ppc_throw_exception");
423 #ifdef PPC_USES_FUNCTION_DESCRIPTOR
424 ppc_ldptr (code, ppc_r2, sizeof (gpointer), ppc_r11);
425 ppc_ldptr (code, ppc_r11, 0, ppc_r11);
427 ppc_mtctr (code, ppc_r11);
428 ppc_bcctrl (code, PPC_BR_ALWAYS, 0);
430 ppc_load_func (code, ppc_r0, mono_ppc_throw_exception);
431 ppc_mtctr (code, ppc_r0);
432 ppc_bcctrl (code, PPC_BR_ALWAYS, 0);
434 /* we should never reach this breakpoint */
436 g_assert ((code - start) <= size);
437 mono_arch_flush_icache (start, code - start);
439 *code_size = code - start;
445 * mono_arch_get_rethrow_exception:
447 * Returns a function pointer which can be used to rethrow
448 * exceptions. The returned function has the following
449 * signature: void (*func) (MonoException *exc);
453 mono_arch_get_rethrow_exception_full (guint32 *code_size, MonoJumpInfo **ji, gboolean aot)
455 int size = MONO_PPC_32_64_CASE (132, 224) + PPC_FTNPTR_SIZE;
459 return mono_arch_get_throw_exception_generic (size, code_size, ji, FALSE, TRUE, aot);
463 * arch_get_throw_exception:
465 * Returns a function pointer which can be used to raise
466 * exceptions. The returned function has the following
467 * signature: void (*func) (MonoException *exc);
468 * For example to raise an arithmetic exception you can use:
470 * x86_push_imm (code, mono_get_exception_arithmetic ());
471 * x86_call_code (code, arch_get_throw_exception ());
475 mono_arch_get_throw_exception_full (guint32 *code_size, MonoJumpInfo **ji, gboolean aot)
477 int size = MONO_PPC_32_64_CASE (132, 224) + PPC_FTNPTR_SIZE;
481 return mono_arch_get_throw_exception_generic (size, code_size, ji, FALSE, FALSE, aot);
485 * arch_get_throw_exception_by_name:
487 * Returns a function pointer which can be used to raise
488 * corlib exceptions. The returned function has the following
489 * signature: void (*func) (char *exc_name);
490 * For example to raise an arithmetic exception you can use:
492 * x86_push_imm (code, "ArithmeticException");
493 * x86_call_code (code, arch_get_throw_exception_by_name ());
497 mono_arch_get_throw_exception_by_name_full (guint32 *code_size, MonoJumpInfo **ji, gboolean aot)
499 guint8 *start, *code;
504 /* Not used on PPC */
505 start = code = mono_global_codeman_reserve (size);
507 mono_arch_flush_icache (start, code - start);
508 *code_size = code - start;
513 * mono_arch_get_throw_corlib_exception:
515 * Returns a function pointer which can be used to raise
516 * corlib exceptions. The returned function has the following
517 * signature: void (*func) (guint32 ex_token, guint32 offset);
518 * On PPC, we pass the ip instead of the offset
521 mono_arch_get_throw_corlib_exception_full (guint32 *code_size, MonoJumpInfo **ji, gboolean aot)
523 int size = MONO_PPC_32_64_CASE (168, 304) + PPC_FTNPTR_SIZE;
527 return mono_arch_get_throw_exception_generic (size, code_size, ji, TRUE, FALSE, aot);
530 /* mono_arch_find_jit_info:
532 * This function is used to gather information from @ctx. It return the
533 * MonoJitInfo of the corresponding function, unwinds one stack frame and
534 * stores the resulting context into @new_ctx. It also stores a string
535 * describing the stack location into @trace (if not NULL), and modifies
536 * the @lmf if necessary. @native_offset return the IP offset from the
537 * start of the function or -1 if that info is not available.
540 mono_arch_find_jit_info (MonoDomain *domain, MonoJitTlsData *jit_tls, MonoJitInfo *res, MonoJitInfo *prev_ji, MonoContext *ctx,
541 MonoContext *new_ctx, MonoLMF **lmf, gboolean *managed)
544 gpointer ip = MONO_CONTEXT_GET_IP (ctx);
545 MonoPPCStackFrame *sframe;
547 /* Avoid costly table lookup during stack overflow */
548 if (prev_ji && (ip > prev_ji->code_start && ((guint8*)ip < ((guint8*)prev_ji->code_start) + prev_ji->code_size)))
551 ji = mono_jit_info_table_find (domain, ip);
561 setup_context (new_ctx);
563 if (*lmf && (MONO_CONTEXT_GET_SP (ctx) >= (gpointer)(*lmf)->ebp)) {
564 /* remove any unused lmf */
565 *lmf = (*lmf)->previous_lmf;
568 address = (char *)ip - (char *)ji->code_start;
571 if (!ji->method->wrapper_type)
574 sframe = (MonoPPCStackFrame*)MONO_CONTEXT_GET_SP (ctx);
575 MONO_CONTEXT_SET_BP (new_ctx, sframe->sp);
576 if (ji->method->save_lmf) {
577 memcpy (&new_ctx->fregs, (char*)sframe->sp - sizeof (double) * MONO_SAVED_FREGS, sizeof (double) * MONO_SAVED_FREGS);
578 memcpy (&new_ctx->regs, (char*)sframe->sp - sizeof (double) * MONO_SAVED_FREGS - sizeof (gulong) * MONO_SAVED_GREGS, sizeof (gulong) * MONO_SAVED_GREGS);
579 } else if (ji->used_regs) {
580 /* keep updated with emit_prolog in mini-ppc.c */
582 /* FIXME handle floating point args
583 for (i = 31; i >= 14; --i) {
584 if (ji->used_fregs & (1 << i)) {
585 offset += sizeof (double);
586 new_ctx->fregs [i - 14] = *(gulong*)((char*)sframe->sp - offset);
589 for (i = 31; i >= 13; --i) {
590 if (ji->used_regs & (1 << i)) {
591 offset += sizeof (gulong);
592 new_ctx->regs [i - 13] = *(gulong*)((char*)sframe->sp - offset);
596 /* the calling IP is in the parent frame */
597 sframe = (MonoPPCStackFrame*)sframe->sp;
598 /* we substract 4, so that the IP points into the call instruction */
599 MONO_CONTEXT_SET_IP (new_ctx, sframe->lr - 4);
605 setup_context (new_ctx);
607 if ((ji = mono_jit_info_table_find (domain, (gpointer)(*lmf)->eip))) {
612 memset (res, 0, MONO_SIZEOF_JIT_INFO);
613 res->method = (*lmf)->method;
616 /*sframe = (MonoPPCStackFrame*)MONO_CONTEXT_GET_SP (ctx);
617 MONO_CONTEXT_SET_BP (new_ctx, sframe->sp);
618 MONO_CONTEXT_SET_IP (new_ctx, sframe->lr);*/
619 MONO_CONTEXT_SET_BP (new_ctx, (*lmf)->ebp);
620 MONO_CONTEXT_SET_IP (new_ctx, (*lmf)->eip);
621 memcpy (&new_ctx->regs, (*lmf)->iregs, sizeof (gulong) * MONO_SAVED_GREGS);
622 memcpy (&new_ctx->fregs, (*lmf)->fregs, sizeof (double) * MONO_SAVED_FREGS);
624 /* FIXME: what about trampoline LMF frames? see exceptions-x86.c */
626 *lmf = (*lmf)->previous_lmf;
628 return ji ? ji : res;
635 * This is the function called from the signal handler
638 mono_arch_sigctx_to_monoctx (void *ctx, MonoContext *mctx)
640 #ifdef MONO_CROSS_COMPILE
641 g_assert_not_reached ();
643 os_ucontext *uc = ctx;
645 mctx->sc_ir = UCONTEXT_REG_NIP(uc);
646 mctx->sc_sp = UCONTEXT_REG_Rn(uc, 1);
647 memcpy (&mctx->regs, &UCONTEXT_REG_Rn(uc, 13), sizeof (gulong) * MONO_SAVED_GREGS);
648 memcpy (&mctx->fregs, &UCONTEXT_REG_FPRn(uc, 14), sizeof (double) * MONO_SAVED_FREGS);
653 mono_arch_monoctx_to_sigctx (MonoContext *mctx, void *ctx)
655 #ifdef MONO_CROSS_COMPILE
656 g_assert_not_reached ();
658 os_ucontext *uc = ctx;
660 UCONTEXT_REG_NIP(uc) = mctx->sc_ir;
661 UCONTEXT_REG_Rn(uc, 1) = mctx->sc_sp;
662 memcpy (&UCONTEXT_REG_Rn(uc, 13), &mctx->regs, sizeof (gulong) * MONO_SAVED_GREGS);
663 memcpy (&UCONTEXT_REG_FPRn(uc, 14), &mctx->fregs, sizeof (double) * MONO_SAVED_FREGS);
668 mono_arch_ip_from_context (void *sigctx)
670 #ifdef MONO_CROSS_COMPILE
671 g_assert_not_reached ();
673 os_ucontext *uc = sigctx;
674 return (gpointer)UCONTEXT_REG_NIP(uc);
679 altstack_handle_and_restore (void *sigctx, gpointer obj, gboolean test_only)
681 void (*restore_context) (MonoContext *);
684 restore_context = mono_get_restore_context ();
685 mono_arch_sigctx_to_monoctx (sigctx, &mctx);
686 mono_handle_exception (&mctx, obj, (gpointer)mctx.sc_ir, test_only);
687 restore_context (&mctx);
691 mono_arch_handle_altstack_exception (void *sigctx, gpointer fault_addr, gboolean stack_ovf)
693 #ifdef MONO_CROSS_COMPILE
694 g_assert_not_reached ();
696 #ifdef MONO_ARCH_USE_SIGACTION
697 os_ucontext *uc = (ucontext_t*)sigctx;
698 os_ucontext *uc_copy;
699 MonoJitInfo *ji = mono_jit_info_table_find (mono_domain_get (), mono_arch_ip_from_context (sigctx));
705 /* we don't do much now, but we can warn the user with a useful message */
706 fprintf (stderr, "Stack overflow: IP: %p, SP: %p\n", mono_arch_ip_from_context (sigctx), (gpointer)UCONTEXT_REG_Rn(uc, 1));
707 if (ji && ji->method)
708 method = mono_method_full_name (ji->method, TRUE);
710 method = "Unmanaged";
711 fprintf (stderr, "At %s\n", method);
715 mono_handle_native_sigsegv (SIGSEGV, sigctx);
716 /* setup a call frame on the real stack so that control is returned there
717 * and exception handling can continue.
718 * The frame looks like:
721 * 224 is the size of the red zone
723 frame_size = sizeof (ucontext_t) + sizeof (gpointer) * 16 + 224;
726 sp = (gpointer)(UCONTEXT_REG_Rn(uc, 1) & ~15);
727 sp = (gpointer)((char*)sp - frame_size);
728 /* may need to adjust pointers in the new struct copy, depending on the OS */
729 uc_copy = (ucontext_t*)(sp + 16);
730 memcpy (uc_copy, uc, sizeof (os_ucontext));
731 #if defined(__linux__) && !defined(__mono_ppc64__)
732 uc_copy->uc_mcontext.uc_regs = (gpointer)((char*)uc_copy + ((char*)uc->uc_mcontext.uc_regs - (char*)uc));
734 g_assert (mono_arch_ip_from_context (uc) == mono_arch_ip_from_context (uc_copy));
735 /* at the return form the signal handler execution starts in altstack_handle_and_restore() */
736 UCONTEXT_REG_LNK(uc) = UCONTEXT_REG_NIP(uc);
737 #ifdef PPC_USES_FUNCTION_DESCRIPTOR
739 MonoPPCFunctionDescriptor *handler_ftnptr = (MonoPPCFunctionDescriptor*)altstack_handle_and_restore;
741 UCONTEXT_REG_NIP(uc) = (gulong)handler_ftnptr->code;
742 UCONTEXT_REG_Rn(uc, 2) = (gulong)handler_ftnptr->toc;
745 UCONTEXT_REG_NIP(uc) = (unsigned long)altstack_handle_and_restore;
747 UCONTEXT_REG_Rn(uc, 1) = (unsigned long)sp;
748 UCONTEXT_REG_Rn(uc, PPC_FIRST_ARG_REG) = (unsigned long)(sp + 16);
749 UCONTEXT_REG_Rn(uc, PPC_FIRST_ARG_REG + 1) = 0;
750 UCONTEXT_REG_Rn(uc, PPC_FIRST_ARG_REG + 2) = 0;
753 #endif /* !MONO_CROSS_COMPILE */
757 mono_arch_handle_exception (void *ctx, gpointer obj, gboolean test_only)
762 mono_arch_sigctx_to_monoctx (ctx, &mctx);
764 result = mono_handle_exception (&mctx, obj, (gpointer)mctx.sc_ir, test_only);
765 /* restore the context so that returning from the signal handler will invoke
768 mono_arch_monoctx_to_sigctx (&mctx, ctx);
773 mono_arch_has_unwind_info (gconstpointer addr)