1 /*
2 * Copyright (c) 1997, 2018, Oracle and/or its affiliates. All rights reserved.
3 * Copyright (c) 2012, 2018 SAP SE. All rights reserved.
4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5 *
6 * This code is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 only, as
8 * published by the Free Software Foundation.
9 *
10 * This code is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
13 * version 2 for more details (a copy is included in the LICENSE file that
14 * accompanied this code).
15 *
16 * You should have received a copy of the GNU General Public License version
17 * 2 along with this work; if not, write to the Free Software Foundation,
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
19 *
20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
21 * or visit www.oracle.com if you need additional information or have any
22 * questions.
23 *
24 */
25
26 // no precompiled headers
27 #include "jvm.h"
28 #include "asm/assembler.inline.hpp"
29 #include "classfile/classLoader.hpp"
30 #include "classfile/systemDictionary.hpp"
31 #include "classfile/vmSymbols.hpp"
32 #include "code/codeCache.hpp"
33 #include "code/icBuffer.hpp"
34 #include "code/vtableStubs.hpp"
35 #include "interpreter/interpreter.hpp"
36 #include "memory/allocation.inline.hpp"
37 #include "nativeInst_ppc.hpp"
38 #include "os_share_aix.hpp"
39 #include "prims/jniFastGetField.hpp"
40 #include "prims/jvm_misc.hpp"
41 #include "porting_aix.hpp"
42 #include "runtime/arguments.hpp"
43 #include "runtime/extendedPC.hpp"
44 #include "runtime/frame.inline.hpp"
45 #include "runtime/interfaceSupport.inline.hpp"
46 #include "runtime/java.hpp"
47 #include "runtime/javaCalls.hpp"
48 #include "runtime/mutexLocker.hpp"
49 #include "runtime/osThread.hpp"
50 #include "runtime/safepointMechanism.hpp"
51 #include "runtime/sharedRuntime.hpp"
52 #include "runtime/stubRoutines.hpp"
53 #include "runtime/thread.inline.hpp"
54 #include "runtime/timer.hpp"
55 #include "utilities/events.hpp"
56 #include "utilities/vmError.hpp"
57 #ifdef COMPILER1
58 #include "c1/c1_Runtime1.hpp"
59 #endif
60 #ifdef COMPILER2
61 #include "opto/runtime.hpp"
62 #endif
63
64 // put OS-includes here
65 # include <ucontext.h>
66
67 address os::current_stack_pointer() {
68 address csp;
69
70 #if !defined(USE_XLC_BUILTINS)
71 // inline assembly for `mr regno(csp), R1_SP':
72 __asm__ __volatile__ ("mr %0, 1":"=r"(csp):);
73 #else
74 csp = (address) __builtin_frame_address(0);
75 #endif
76
77 return csp;
78 }
79
80 char* os::non_memory_address_word() {
81 // Must never look like an address returned by reserve_memory,
82 // even in its subfields (as defined by the CPU immediate fields,
83 // if the CPU splits constants across multiple instructions).
84
85 return (char*) -1;
86 }
87
88 // Frame information (pc, sp, fp) retrieved via ucontext
89 // always looks like a C-frame according to the frame
90 // conventions in frame_ppc.hpp.
91
92 address os::Aix::ucontext_get_pc(const ucontext_t * uc) {
93 return (address)uc->uc_mcontext.jmp_context.iar;
94 }
95
96 intptr_t* os::Aix::ucontext_get_sp(const ucontext_t * uc) {
97 // gpr1 holds the stack pointer on aix
98 return (intptr_t*)uc->uc_mcontext.jmp_context.gpr[1/*REG_SP*/];
99 }
100
101 intptr_t* os::Aix::ucontext_get_fp(const ucontext_t * uc) {
102 return NULL;
103 }
104
105 void os::Aix::ucontext_set_pc(ucontext_t* uc, address new_pc) {
106 uc->uc_mcontext.jmp_context.iar = (uint64_t) new_pc;
107 }
108
109 static address ucontext_get_lr(const ucontext_t * uc) {
110 return (address)uc->uc_mcontext.jmp_context.lr;
111 }
112
113 ExtendedPC os::fetch_frame_from_context(const void* ucVoid,
114 intptr_t** ret_sp, intptr_t** ret_fp) {
115
116 ExtendedPC epc;
117 const ucontext_t* uc = (const ucontext_t*)ucVoid;
118
119 if (uc != NULL) {
120 epc = ExtendedPC(os::Aix::ucontext_get_pc(uc));
121 if (ret_sp) *ret_sp = os::Aix::ucontext_get_sp(uc);
122 if (ret_fp) *ret_fp = os::Aix::ucontext_get_fp(uc);
123 } else {
124 // construct empty ExtendedPC for return value checking
125 epc = ExtendedPC(NULL);
126 if (ret_sp) *ret_sp = (intptr_t *)NULL;
127 if (ret_fp) *ret_fp = (intptr_t *)NULL;
128 }
129
130 return epc;
131 }
132
133 frame os::fetch_frame_from_context(const void* ucVoid) {
134 intptr_t* sp;
135 intptr_t* fp;
136 ExtendedPC epc = fetch_frame_from_context(ucVoid, &sp, &fp);
137 // Avoid crash during crash if pc broken.
138 if (epc.pc()) {
139 frame fr(sp, epc.pc());
140 return fr;
141 }
142 frame fr(sp);
143 return fr;
144 }
145
146 bool os::Aix::get_frame_at_stack_banging_point(JavaThread* thread, ucontext_t* uc, frame* fr) {
147 address pc = (address) os::Aix::ucontext_get_pc(uc);
148 if (Interpreter::contains(pc)) {
149 // Interpreter performs stack banging after the fixed frame header has
150 // been generated while the compilers perform it before. To maintain
151 // semantic consistency between interpreted and compiled frames, the
152 // method returns the Java sender of the current frame.
153 *fr = os::fetch_frame_from_context(uc);
154 if (!fr->is_first_java_frame()) {
155 assert(fr->safe_for_sender(thread), "Safety check");
156 *fr = fr->java_sender();
157 }
158 } else {
159 // More complex code with compiled code.
160 assert(!Interpreter::contains(pc), "Interpreted methods should have been handled above");
161 CodeBlob* cb = CodeCache::find_blob(pc);
162 if (cb == NULL || !cb->is_nmethod() || cb->is_frame_complete_at(pc)) {
163 // Not sure where the pc points to, fallback to default
164 // stack overflow handling. In compiled code, we bang before
165 // the frame is complete.
166 return false;
167 } else {
168 intptr_t* sp = os::Aix::ucontext_get_sp(uc);
169 address lr = ucontext_get_lr(uc);
170 *fr = frame(sp, lr);
171 if (!fr->is_java_frame()) {
172 assert(fr->safe_for_sender(thread), "Safety check");
173 assert(!fr->is_first_frame(), "Safety check");
174 *fr = fr->java_sender();
175 }
176 }
177 }
178 assert(fr->is_java_frame(), "Safety check");
179 return true;
180 }
181
182 frame os::get_sender_for_C_frame(frame* fr) {
183 if (*fr->sp() == NULL) {
184 // fr is the last C frame
185 return frame(NULL, NULL);
186 }
187 return frame(fr->sender_sp(), fr->sender_pc());
188 }
189
190
191 frame os::current_frame() {
192 intptr_t* csp = (intptr_t*) *((intptr_t*) os::current_stack_pointer());
193 // hack.
194 frame topframe(csp, (address)0x8);
195 // Return sender of sender of current topframe which hopefully
196 // both have pc != NULL.
197 frame tmp = os::get_sender_for_C_frame(&topframe);
198 return os::get_sender_for_C_frame(&tmp);
199 }
200
201 // Utility functions
202
203 extern "C" JNIEXPORT int
204 JVM_handle_aix_signal(int sig, siginfo_t* info, void* ucVoid, int abort_if_unrecognized) {
205
206 ucontext_t* uc = (ucontext_t*) ucVoid;
207
208 Thread* t = Thread::current_or_null_safe();
209
210 SignalHandlerMark shm(t);
211
212 // Note: it's not uncommon that JNI code uses signal/sigset to install
213 // then restore certain signal handler (e.g. to temporarily block SIGPIPE,
214 // or have a SIGILL handler when detecting CPU type). When that happens,
215 // JVM_handle_aix_signal() might be invoked with junk info/ucVoid. To
216 // avoid unnecessary crash when libjsig is not preloaded, try handle signals
217 // that do not require siginfo/ucontext first.
218
219 if (sig == SIGPIPE) {
220 if (os::Aix::chained_handler(sig, info, ucVoid)) {
221 return 1;
222 } else {
223 // Ignoring SIGPIPE - see bugs 4229104
224 return 1;
225 }
226 }
227
228 JavaThread* thread = NULL;
229 VMThread* vmthread = NULL;
230 if (os::Aix::signal_handlers_are_installed) {
231 if (t != NULL) {
232 if(t->is_Java_thread()) {
233 thread = (JavaThread*)t;
234 }
235 else if(t->is_VM_thread()) {
236 vmthread = (VMThread *)t;
237 }
238 }
239 }
240
241 // Decide if this trap can be handled by a stub.
242 address stub = NULL;
243
244 // retrieve program counter
245 address const pc = uc ? os::Aix::ucontext_get_pc(uc) : NULL;
246
247 // retrieve crash address
248 address const addr = info ? (const address) info->si_addr : NULL;
249
250 // SafeFetch 32 handling:
251 // - make it work if _thread is null
252 // - make it use the standard os::...::ucontext_get/set_pc APIs
253 if (uc) {
254 address const pc = os::Aix::ucontext_get_pc(uc);
255 if (pc && StubRoutines::is_safefetch_fault(pc)) {
256 os::Aix::ucontext_set_pc(uc, StubRoutines::continuation_for_safefetch_fault(pc));
257 return true;
258 }
259 }
260
261 if (info == NULL || uc == NULL || thread == NULL && vmthread == NULL) {
262 goto run_chained_handler;
263 }
264
265 // If we are a java thread...
266 if (thread != NULL) {
267
268 // Handle ALL stack overflow variations here
269 if (sig == SIGSEGV && thread->on_local_stack(addr)) {
270 // stack overflow
271 //
272 // If we are in a yellow zone and we are inside java, we disable the yellow zone and
273 // throw a stack overflow exception.
274 // If we are in native code or VM C code, we report-and-die. The original coding tried
275 // to continue with yellow zone disabled, but that doesn't buy us much and prevents
276 // hs_err_pid files.
277 if (thread->in_stack_yellow_reserved_zone(addr)) {
278 if (thread->thread_state() == _thread_in_Java) {
279 if (thread->in_stack_reserved_zone(addr)) {
280 frame fr;
281 if (os::Aix::get_frame_at_stack_banging_point(thread, uc, &fr)) {
282 assert(fr.is_java_frame(), "Must be a Javac frame");
283 frame activation =
284 SharedRuntime::look_for_reserved_stack_annotated_method(thread, fr);
285 if (activation.sp() != NULL) {
286 thread->disable_stack_reserved_zone();
287 if (activation.is_interpreted_frame()) {
288 thread->set_reserved_stack_activation((address)activation.fp());
289 } else {
290 thread->set_reserved_stack_activation((address)activation.unextended_sp());
291 }
292 return 1;
293 }
294 }
295 }
296 // Throw a stack overflow exception.
297 // Guard pages will be reenabled while unwinding the stack.
298 thread->disable_stack_yellow_reserved_zone();
299 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::STACK_OVERFLOW);
300 goto run_stub;
301 } else {
302 // Thread was in the vm or native code. Return and try to finish.
303 thread->disable_stack_yellow_reserved_zone();
304 return 1;
305 }
306 } else if (thread->in_stack_red_zone(addr)) {
307 // Fatal red zone violation. Disable the guard pages and fall through
308 // to handle_unexpected_exception way down below.
309 thread->disable_stack_red_zone();
310 tty->print_raw_cr("An irrecoverable stack overflow has occurred.");
311 goto report_and_die;
312 } else {
313 // This means a segv happened inside our stack, but not in
314 // the guarded zone. I'd like to know when this happens,
315 tty->print_raw_cr("SIGSEGV happened inside stack but outside yellow and red zone.");
316 goto report_and_die;
317 }
318
319 } // end handle SIGSEGV inside stack boundaries
320
321 if (thread->thread_state() == _thread_in_Java) {
322 // Java thread running in Java code
323
324 // The following signals are used for communicating VM events:
325 //
326 // SIGILL: the compiler generates illegal opcodes
327 // at places where it wishes to interrupt the VM:
328 // Safepoints, Unreachable Code, Entry points of Zombie methods,
329 // This results in a SIGILL with (*pc) == inserted illegal instruction.
330 //
331 // (so, SIGILLs with a pc inside the zero page are real errors)
332 //
333 // SIGTRAP:
334 // The ppc trap instruction raises a SIGTRAP and is very efficient if it
335 // does not trap. It is used for conditional branches that are expected
336 // to be never taken. These are:
337 // - zombie methods
338 // - IC (inline cache) misses.
339 // - null checks leading to UncommonTraps.
340 // - range checks leading to Uncommon Traps.
341 // On Aix, these are especially null checks, as the ImplicitNullCheck
342 // optimization works only in rare cases, as the page at address 0 is only
343 // write protected. //
344 // Note: !UseSIGTRAP is used to prevent SIGTRAPS altogether, to facilitate debugging.
345 //
346 // SIGSEGV:
347 // used for safe point polling:
348 // To notify all threads that they have to reach a safe point, safe point polling is used:
349 // All threads poll a certain mapped memory page. Normally, this page has read access.
350 // If the VM wants to inform the threads about impending safe points, it puts this
351 // page to read only ("poisens" the page), and the threads then reach a safe point.
352 // used for null checks:
353 // If the compiler finds a store it uses it for a null check. Unfortunately this
354 // happens rarely. In heap based and disjoint base compressd oop modes also loads
355 // are used for null checks.
356
357 // A VM-related SIGILL may only occur if we are not in the zero page.
358 // On AIX, we get a SIGILL if we jump to 0x0 or to somewhere else
359 // in the zero page, because it is filled with 0x0. We ignore
360 // explicit SIGILLs in the zero page.
361 if (sig == SIGILL && (pc < (address) 0x200)) {
362 if (TraceTraps) {
363 tty->print_raw_cr("SIGILL happened inside zero page.");
364 }
365 goto report_and_die;
366 }
367
368 // Handle signal from NativeJump::patch_verified_entry().
369 if (( TrapBasedNotEntrantChecks && sig == SIGTRAP && nativeInstruction_at(pc)->is_sigtrap_zombie_not_entrant()) ||
370 (!TrapBasedNotEntrantChecks && sig == SIGILL && nativeInstruction_at(pc)->is_sigill_zombie_not_entrant())) {
371 if (TraceTraps) {
372 tty->print_cr("trap: zombie_not_entrant (%s)", (sig == SIGTRAP) ? "SIGTRAP" : "SIGILL");
373 }
374 stub = SharedRuntime::get_handle_wrong_method_stub();
375 goto run_stub;
376 }
377
378 else if ((SafepointMechanism::uses_thread_local_poll() && USE_POLL_BIT_ONLY)
379 ? (sig == SIGTRAP && ((NativeInstruction*)pc)->is_safepoint_poll())
380 : (sig == SIGSEGV && os::is_poll_address(addr))) {
381 if (TraceTraps) {
382 tty->print_cr("trap: safepoint_poll at " INTPTR_FORMAT " (%s)", p2i(pc),
383 (SafepointMechanism::uses_thread_local_poll() && USE_POLL_BIT_ONLY) ? "SIGTRAP" : "SIGSEGV");
384 }
385 stub = SharedRuntime::get_poll_stub(pc);
386 goto run_stub;
387 }
388
389 // SIGTRAP-based ic miss check in compiled code.
390 else if (sig == SIGTRAP && TrapBasedICMissChecks &&
391 nativeInstruction_at(pc)->is_sigtrap_ic_miss_check()) {
392 if (TraceTraps) {
393 tty->print_cr("trap: ic_miss_check at " INTPTR_FORMAT " (SIGTRAP)", pc);
394 }
395 stub = SharedRuntime::get_ic_miss_stub();
396 goto run_stub;
397 }
398
399 // SIGTRAP-based implicit null check in compiled code.
400 else if (sig == SIGTRAP && TrapBasedNullChecks &&
401 nativeInstruction_at(pc)->is_sigtrap_null_check()) {
402 if (TraceTraps) {
403 tty->print_cr("trap: null_check at " INTPTR_FORMAT " (SIGTRAP)", pc);
404 }
405 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL);
406 goto run_stub;
407 }
408
409 // SIGSEGV-based implicit null check in compiled code.
410 else if (sig == SIGSEGV && ImplicitNullChecks &&
411 CodeCache::contains((void*) pc) &&
412 MacroAssembler::uses_implicit_null_check(info->si_addr)) {
413 if (TraceTraps) {
414 tty->print_cr("trap: null_check at " INTPTR_FORMAT " (SIGSEGV)", pc);
415 }
416 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL);
417 }
418
419 #ifdef COMPILER2
420 // SIGTRAP-based implicit range check in compiled code.
421 else if (sig == SIGTRAP && TrapBasedRangeChecks &&
422 nativeInstruction_at(pc)->is_sigtrap_range_check()) {
423 if (TraceTraps) {
424 tty->print_cr("trap: range_check at " INTPTR_FORMAT " (SIGTRAP)", pc);
425 }
426 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL);
427 goto run_stub;
428 }
429 #endif
430
431 else if (sig == SIGFPE /* && info->si_code == FPE_INTDIV */) {
432 if (TraceTraps) {
433 tty->print_raw_cr("Fix SIGFPE handler, trying divide by zero handler.");
434 }
435 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO);
436 goto run_stub;
437 }
438
439 else if (sig == SIGBUS) {
440 // BugId 4454115: A read from a MappedByteBuffer can fault here if the
441 // underlying file has been truncated. Do not crash the VM in such a case.
442 CodeBlob* cb = CodeCache::find_blob_unsafe(pc);
443 CompiledMethod* nm = cb->as_compiled_method_or_null();
444 if (nm != NULL && nm->has_unsafe_access()) {
445 address next_pc = pc + 4;
446 next_pc = SharedRuntime::handle_unsafe_access(thread, next_pc);
447 os::Aix::ucontext_set_pc(uc, next_pc);
448 return 1;
449 }
450 }
451 }
452
453 else { // thread->thread_state() != _thread_in_Java
454 // Detect CPU features. This is only done at the very start of the VM. Later, the
455 // VM_Version::is_determine_features_test_running() flag should be false.
456
457 if (sig == SIGILL && VM_Version::is_determine_features_test_running()) {
458 // SIGILL must be caused by VM_Version::determine_features().
459 *(int *)pc = 0; // patch instruction to 0 to indicate that it causes a SIGILL,
460 // flushing of icache is not necessary.
461 stub = pc + 4; // continue with next instruction.
462 goto run_stub;
463 }
464 else if (thread->thread_state() == _thread_in_vm &&
465 sig == SIGBUS && thread->doing_unsafe_access()) {
466 address next_pc = pc + 4;
467 next_pc = SharedRuntime::handle_unsafe_access(thread, next_pc);
468 os::Aix::ucontext_set_pc(uc, next_pc);
469 return 1;
470 }
471 }
472
473 // Check to see if we caught the safepoint code in the
474 // process of write protecting the memory serialization page.
475 // It write enables the page immediately after protecting it
476 // so we can just return to retry the write.
477 if ((sig == SIGSEGV) &&
478 os::is_memory_serialize_page(thread, addr)) {
479 // Synchronization problem in the pseudo memory barrier code (bug id 6546278)
480 // Block current thread until the memory serialize page permission restored.
481 os::block_on_serialize_page_trap();
482 return true;
483 }
484 }
485
486 run_stub:
487
488 // One of the above code blocks ininitalized the stub, so we want to
489 // delegate control to that stub.
490 if (stub != NULL) {
491 // Save all thread context in case we need to restore it.
492 if (thread != NULL) thread->set_saved_exception_pc(pc);
493 os::Aix::ucontext_set_pc(uc, stub);
494 return 1;
495 }
496
497 run_chained_handler:
498
499 // signal-chaining
500 if (os::Aix::chained_handler(sig, info, ucVoid)) {
501 return 1;
502 }
503 if (!abort_if_unrecognized) {
504 // caller wants another chance, so give it to him
505 return 0;
506 }
507
508 report_and_die:
509
510 // Use sigthreadmask instead of sigprocmask on AIX and unmask current signal.
511 sigset_t newset;
512 sigemptyset(&newset);
513 sigaddset(&newset, sig);
514 sigthreadmask(SIG_UNBLOCK, &newset, NULL);
515
516 VMError::report_and_die(t, sig, pc, info, ucVoid);
517
518 ShouldNotReachHere();
519 return 0;
520 }
521
522 void os::Aix::init_thread_fpu_state(void) {
523 #if !defined(USE_XLC_BUILTINS)
524 // Disable FP exceptions.
525 __asm__ __volatile__ ("mtfsfi 6,0");
526 #else
527 __mtfsfi(6, 0);
528 #endif
529 }
530
531 ////////////////////////////////////////////////////////////////////////////////
532 // thread stack
533
534 // Minimum usable stack sizes required to get to user code. Space for
535 // HotSpot guard pages is added later.
536 size_t os::Posix::_compiler_thread_min_stack_allowed = 192 * K;
537 size_t os::Posix::_java_thread_min_stack_allowed = 64 * K;
538 size_t os::Posix::_vm_internal_thread_min_stack_allowed = 64 * K;
539
540 // Return default stack size for thr_type.
541 size_t os::Posix::default_stack_size(os::ThreadType thr_type) {
542 // Default stack size (compiler thread needs larger stack).
543 size_t s = (thr_type == os::compiler_thread ? 4 * M : 1 * M);
544 return s;
545 }
546
547 /////////////////////////////////////////////////////////////////////////////
548 // helper functions for fatal error handler
549
550 void os::print_context(outputStream *st, const void *context) {
551 if (context == NULL) return;
552
553 const ucontext_t* uc = (const ucontext_t*)context;
554
555 st->print_cr("Registers:");
556 st->print("pc =" INTPTR_FORMAT " ", uc->uc_mcontext.jmp_context.iar);
557 st->print("lr =" INTPTR_FORMAT " ", uc->uc_mcontext.jmp_context.lr);
558 st->print("ctr=" INTPTR_FORMAT " ", uc->uc_mcontext.jmp_context.ctr);
559 st->cr();
560 for (int i = 0; i < 32; i++) {
561 st->print("r%-2d=" INTPTR_FORMAT " ", i, uc->uc_mcontext.jmp_context.gpr[i]);
562 if (i % 3 == 2) st->cr();
563 }
564 st->cr();
565 st->cr();
566
567 intptr_t *sp = (intptr_t *)os::Aix::ucontext_get_sp(uc);
568 st->print_cr("Top of Stack: (sp=" PTR_FORMAT ")", sp);
569 print_hex_dump(st, (address)sp, (address)(sp + 128), sizeof(intptr_t));
570 st->cr();
571
572 // Note: it may be unsafe to inspect memory near pc. For example, pc may
573 // point to garbage if entry point in an nmethod is corrupted. Leave
574 // this at the end, and hope for the best.
575 address pc = os::Aix::ucontext_get_pc(uc);
576 st->print_cr("Instructions: (pc=" PTR_FORMAT ")", pc);
577 print_hex_dump(st, pc - 64, pc + 64, /*instrsize=*/4);
578 st->cr();
579
580 // Try to decode the instructions.
581 st->print_cr("Decoded instructions: (pc=" PTR_FORMAT ")", pc);
582 st->print("<TODO: PPC port - print_context>");
583 // TODO: PPC port Disassembler::decode(pc, 16, 16, st);
584 st->cr();
585 }
586
587 void os::print_register_info(outputStream *st, const void *context) {
588 if (context == NULL) return;
589
590 ucontext_t *uc = (ucontext_t*)context;
591
592 st->print_cr("Register to memory mapping:");
593 st->cr();
594
595 st->print("pc ="); print_location(st, (intptr_t)uc->uc_mcontext.jmp_context.iar);
596 st->print("lr ="); print_location(st, (intptr_t)uc->uc_mcontext.jmp_context.lr);
597 st->print("sp ="); print_location(st, (intptr_t)os::Aix::ucontext_get_sp(uc));
598 for (int i = 0; i < 32; i++) {
599 st->print("r%-2d=", i);
600 print_location(st, (intptr_t)uc->uc_mcontext.jmp_context.gpr[i]);
601 }
602
603 st->cr();
604 }
605
606 extern "C" {
607 int SpinPause() {
608 return 0;
609 }
610 }
611
612 #ifndef PRODUCT
613 void os::verify_stack_alignment() {
614 assert(((intptr_t)os::current_stack_pointer() & (StackAlignmentInBytes-1)) == 0, "incorrect stack alignment");
615 }
616 #endif
617
618 int os::extra_bang_size_in_bytes() {
619 // PPC does not require the additional stack bang.
620 return 0;
621 }
622
623 bool os::platform_print_native_stack(outputStream* st, void* context, char *buf, int buf_size) {
624 AixNativeCallstack::print_callstack_for_context(st, (const ucontext_t*)context, true, buf, (size_t) buf_size);
625 return true;
626 }