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comparison src/os_cpu/linux_ppc/vm/os_linux_ppc.cpp @ 14408:ec28f9c041ff

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8019972: PPC64 (part 9): platform files for interpreter only VM. Summary: With this change the HotSpot core build works on Linux/PPC64. The VM succesfully executes simple test programs. Reviewed-by: kvn
author goetz
date Fri, 02 Aug 2013 16:46:45 +0200
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children 67fa91961822
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14407:94c202aa2646 14408:ec28f9c041ff
1 /*
2 * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
3 * Copyright 2012, 2013 SAP AG. 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 hat
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 "assembler_ppc.inline.hpp"
28 #include "classfile/classLoader.hpp"
29 #include "classfile/systemDictionary.hpp"
30 #include "classfile/vmSymbols.hpp"
31 #include "code/icBuffer.hpp"
32 #include "code/vtableStubs.hpp"
33 #include "interpreter/interpreter.hpp"
34 #include "jvm_linux.h"
35 #include "memory/allocation.inline.hpp"
36 #include "mutex_linux.inline.hpp"
37 #include "nativeInst_ppc.hpp"
38 #include "os_share_linux.hpp"
39 #include "prims/jniFastGetField.hpp"
40 #include "prims/jvm.h"
41 #include "prims/jvm_misc.hpp"
42 #include "runtime/arguments.hpp"
43 #include "runtime/extendedPC.hpp"
44 #include "runtime/frame.inline.hpp"
45 #include "runtime/interfaceSupport.hpp"
46 #include "runtime/java.hpp"
47 #include "runtime/javaCalls.hpp"
48 #include "runtime/mutexLocker.hpp"
49 #include "runtime/osThread.hpp"
50 #include "runtime/sharedRuntime.hpp"
51 #include "runtime/stubRoutines.hpp"
52 #include "runtime/thread.inline.hpp"
53 #include "runtime/timer.hpp"
54 #include "utilities/events.hpp"
55 #include "utilities/vmError.hpp"
56
57 // put OS-includes here
58 # include <sys/types.h>
59 # include <sys/mman.h>
60 # include <pthread.h>
61 # include <signal.h>
62 # include <errno.h>
63 # include <dlfcn.h>
64 # include <stdlib.h>
65 # include <stdio.h>
66 # include <unistd.h>
67 # include <sys/resource.h>
68 # include <pthread.h>
69 # include <sys/stat.h>
70 # include <sys/time.h>
71 # include <sys/utsname.h>
72 # include <sys/socket.h>
73 # include <sys/wait.h>
74 # include <pwd.h>
75 # include <poll.h>
76 # include <ucontext.h>
77
78
79 address os::current_stack_pointer() {
80 intptr_t* csp;
81
82 // inline assembly `mr regno(csp), R1_SP':
83 __asm__ __volatile__ ("mr %0, 1":"=r"(csp):);
84
85 return (address) csp;
86 }
87
88 char* os::non_memory_address_word() {
89 // Must never look like an address returned by reserve_memory,
90 // even in its subfields (as defined by the CPU immediate fields,
91 // if the CPU splits constants across multiple instructions).
92
93 return (char*) -1;
94 }
95
96 void os::initialize_thread(Thread *thread) { }
97
98 // Frame information (pc, sp, fp) retrieved via ucontext
99 // always looks like a C-frame according to the frame
100 // conventions in frame_ppc64.hpp.
101 address os::Linux::ucontext_get_pc(ucontext_t * uc) {
102 // On powerpc64, ucontext_t is not selfcontained but contains
103 // a pointer to an optional substructure (mcontext_t.regs) containing the volatile
104 // registers - NIP, among others.
105 // This substructure may or may not be there depending where uc came from:
106 // - if uc was handed over as the argument to a sigaction handler, a pointer to the
107 // substructure was provided by the kernel when calling the signal handler, and
108 // regs->nip can be accessed.
109 // - if uc was filled by getcontext(), it is undefined - getcontext() does not fill
110 // it because the volatile registers are not needed to make setcontext() work.
111 // Hopefully it was zero'd out beforehand.
112 guarantee(uc->uc_mcontext.regs != NULL, "only use ucontext_get_pc in sigaction context");
113 return (address)uc->uc_mcontext.regs->nip;
114 }
115
116 intptr_t* os::Linux::ucontext_get_sp(ucontext_t * uc) {
117 return (intptr_t*)uc->uc_mcontext.regs->gpr[1/*REG_SP*/];
118 }
119
120 intptr_t* os::Linux::ucontext_get_fp(ucontext_t * uc) {
121 return NULL;
122 }
123
124 ExtendedPC os::fetch_frame_from_context(void* ucVoid,
125 intptr_t** ret_sp, intptr_t** ret_fp) {
126
127 ExtendedPC epc;
128 ucontext_t* uc = (ucontext_t*)ucVoid;
129
130 if (uc != NULL) {
131 epc = ExtendedPC(os::Linux::ucontext_get_pc(uc));
132 if (ret_sp) *ret_sp = os::Linux::ucontext_get_sp(uc);
133 if (ret_fp) *ret_fp = os::Linux::ucontext_get_fp(uc);
134 } else {
135 // construct empty ExtendedPC for return value checking
136 epc = ExtendedPC(NULL);
137 if (ret_sp) *ret_sp = (intptr_t *)NULL;
138 if (ret_fp) *ret_fp = (intptr_t *)NULL;
139 }
140
141 return epc;
142 }
143
144 frame os::fetch_frame_from_context(void* ucVoid) {
145 intptr_t* sp;
146 intptr_t* fp;
147 ExtendedPC epc = fetch_frame_from_context(ucVoid, &sp, &fp);
148 return frame(sp, epc.pc());
149 }
150
151 frame os::get_sender_for_C_frame(frame* fr) {
152 if (*fr->sp() == 0) {
153 // fr is the last C frame
154 return frame(NULL, NULL);
155 }
156 return frame(fr->sender_sp(), fr->sender_pc());
157 }
158
159
160 frame os::current_frame() {
161 intptr_t* csp = (intptr_t*) *((intptr_t*) os::current_stack_pointer());
162 // hack.
163 frame topframe(csp, (address)0x8);
164 // return sender of current topframe which hopefully has pc != NULL.
165 return os::get_sender_for_C_frame(&topframe);
166 }
167
168 // Utility functions
169
170 extern "C" JNIEXPORT int
171 JVM_handle_linux_signal(int sig,
172 siginfo_t* info,
173 void* ucVoid,
174 int abort_if_unrecognized) {
175 ucontext_t* uc = (ucontext_t*) ucVoid;
176
177 Thread* t = ThreadLocalStorage::get_thread_slow();
178
179 SignalHandlerMark shm(t);
180
181 // Note: it's not uncommon that JNI code uses signal/sigset to install
182 // then restore certain signal handler (e.g. to temporarily block SIGPIPE,
183 // or have a SIGILL handler when detecting CPU type). When that happens,
184 // JVM_handle_linux_signal() might be invoked with junk info/ucVoid. To
185 // avoid unnecessary crash when libjsig is not preloaded, try handle signals
186 // that do not require siginfo/ucontext first.
187
188 if (sig == SIGPIPE) {
189 if (os::Linux::chained_handler(sig, info, ucVoid)) {
190 return true;
191 } else {
192 if (PrintMiscellaneous && (WizardMode || Verbose)) {
193 warning("Ignoring SIGPIPE - see bug 4229104");
194 }
195 return true;
196 }
197 }
198
199 JavaThread* thread = NULL;
200 VMThread* vmthread = NULL;
201 if (os::Linux::signal_handlers_are_installed) {
202 if (t != NULL) {
203 if(t->is_Java_thread()) {
204 thread = (JavaThread*)t;
205 } else if(t->is_VM_thread()) {
206 vmthread = (VMThread *)t;
207 }
208 }
209 }
210
211 // Moved SafeFetch32 handling outside thread!=NULL conditional block to make
212 // it work if no associated JavaThread object exists.
213 if (uc) {
214 address const pc = os::Linux::ucontext_get_pc(uc);
215 if (pc && StubRoutines::is_safefetch_fault(pc)) {
216 uc->uc_mcontext.regs->nip = (unsigned long)StubRoutines::continuation_for_safefetch_fault(pc);
217 return true;
218 }
219 }
220
221 // decide if this trap can be handled by a stub
222 address stub = NULL;
223 address pc = NULL;
224
225 //%note os_trap_1
226 if (info != NULL && uc != NULL && thread != NULL) {
227 pc = (address) os::Linux::ucontext_get_pc(uc);
228
229 // Handle ALL stack overflow variations here
230 if (sig == SIGSEGV) {
231 // Si_addr may not be valid due to a bug in the linux-ppc64 kernel (see
232 // comment below). Use get_stack_bang_address instead of si_addr.
233 address addr = ((NativeInstruction*)pc)->get_stack_bang_address(uc);
234
235 // Check if fault address is within thread stack.
236 if (addr < thread->stack_base() &&
237 addr >= thread->stack_base() - thread->stack_size()) {
238 // stack overflow
239 if (thread->in_stack_yellow_zone(addr)) {
240 thread->disable_stack_yellow_zone();
241 if (thread->thread_state() == _thread_in_Java) {
242 // Throw a stack overflow exception.
243 // Guard pages will be reenabled while unwinding the stack.
244 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::STACK_OVERFLOW);
245 } else {
246 // Thread was in the vm or native code. Return and try to finish.
247 return 1;
248 }
249 } else if (thread->in_stack_red_zone(addr)) {
250 // Fatal red zone violation. Disable the guard pages and fall through
251 // to handle_unexpected_exception way down below.
252 thread->disable_stack_red_zone();
253 tty->print_raw_cr("An irrecoverable stack overflow has occurred.");
254
255 // This is a likely cause, but hard to verify. Let's just print
256 // it as a hint.
257 tty->print_raw_cr("Please check if any of your loaded .so files has "
258 "enabled executable stack (see man page execstack(8))");
259 } else {
260 // Accessing stack address below sp may cause SEGV if current
261 // thread has MAP_GROWSDOWN stack. This should only happen when
262 // current thread was created by user code with MAP_GROWSDOWN flag
263 // and then attached to VM. See notes in os_linux.cpp.
264 if (thread->osthread()->expanding_stack() == 0) {
265 thread->osthread()->set_expanding_stack();
266 if (os::Linux::manually_expand_stack(thread, addr)) {
267 thread->osthread()->clear_expanding_stack();
268 return 1;
269 }
270 thread->osthread()->clear_expanding_stack();
271 } else {
272 fatal("recursive segv. expanding stack.");
273 }
274 }
275 }
276 }
277
278 if (thread->thread_state() == _thread_in_Java) {
279 // Java thread running in Java code => find exception handler if any
280 // a fault inside compiled code, the interpreter, or a stub
281
282 // A VM-related SIGILL may only occur if we are not in the zero page.
283 // On AIX, we get a SIGILL if we jump to 0x0 or to somewhere else
284 // in the zero page, because it is filled with 0x0. We ignore
285 // explicit SIGILLs in the zero page.
286 if (sig == SIGILL && (pc < (address) 0x200)) {
287 if (TraceTraps)
288 tty->print_raw_cr("SIGILL happened inside zero page.");
289 goto report_and_die;
290 }
291
292 // Handle signal from NativeJump::patch_verified_entry().
293 if (( TrapBasedNotEntrantChecks && sig == SIGTRAP && nativeInstruction_at(pc)->is_sigtrap_zombie_not_entrant()) ||
294 (!TrapBasedNotEntrantChecks && sig == SIGILL && nativeInstruction_at(pc)->is_sigill_zombie_not_entrant())) {
295 if (TraceTraps)
296 tty->print_cr("trap: zombie_not_entrant (%s)", (sig == SIGTRAP) ? "SIGTRAP" : "SIGILL");
297 stub = SharedRuntime::get_handle_wrong_method_stub();
298 }
299
300 else if (sig == SIGSEGV &&
301 // A linux-ppc64 kernel before 2.6.6 doesn't set si_addr on some segfaults
302 // in 64bit mode (cf. http://www.kernel.org/pub/linux/kernel/v2.6/ChangeLog-2.6.6),
303 // especially when we try to read from the safepoint polling page. So the check
304 // (address)info->si_addr == os::get_standard_polling_page()
305 // doesn't work for us. We use:
306 ((NativeInstruction*)pc)->is_safepoint_poll()) {
307 if (TraceTraps)
308 tty->print_cr("trap: safepoint_poll at " INTPTR_FORMAT " (SIGSEGV)", pc);
309 stub = SharedRuntime::get_poll_stub(pc);
310 }
311
312 // SIGTRAP-based ic miss check in compiled code.
313 else if (sig == SIGTRAP && TrapBasedICMissChecks &&
314 nativeInstruction_at(pc)->is_sigtrap_ic_miss_check()) {
315 if (TraceTraps)
316 tty->print_cr("trap: ic_miss_check at " INTPTR_FORMAT " (SIGTRAP)", pc);
317 stub = SharedRuntime::get_ic_miss_stub();
318 }
319
320 // SIGTRAP-based implicit null check in compiled code.
321 else if (sig == SIGTRAP && TrapBasedNullChecks &&
322 nativeInstruction_at(pc)->is_sigtrap_null_check()) {
323 if (TraceTraps)
324 tty->print_cr("trap: null_check at " INTPTR_FORMAT " (SIGTRAP)", pc);
325 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL);
326 }
327
328 // SIGSEGV-based implicit null check in compiled code.
329 else if (sig == SIGSEGV && ImplicitNullChecks &&
330 CodeCache::contains((void*) pc) &&
331 !MacroAssembler::needs_explicit_null_check((intptr_t) info->si_addr)) {
332 if (TraceTraps)
333 tty->print_cr("trap: null_check at " INTPTR_FORMAT " (SIGSEGV)", pc);
334 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL);
335 }
336
337 #ifdef COMPILER2
338 // SIGTRAP-based implicit range check in compiled code.
339 else if (sig == SIGTRAP && TrapBasedRangeChecks &&
340 nativeInstruction_at(pc)->is_sigtrap_range_check()) {
341 if (TraceTraps)
342 tty->print_cr("trap: range_check at " INTPTR_FORMAT " (SIGTRAP)", pc);
343 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL);
344 }
345 #endif
346 else if (sig == SIGBUS) {
347 // BugId 4454115: A read from a MappedByteBuffer can fault here if the
348 // underlying file has been truncated. Do not crash the VM in such a case.
349 CodeBlob* cb = CodeCache::find_blob_unsafe(pc);
350 nmethod* nm = (cb != NULL && cb->is_nmethod()) ? (nmethod*)cb : NULL;
351 if (nm != NULL && nm->has_unsafe_access()) {
352 // We don't really need a stub here! Just set the pending exeption and
353 // continue at the next instruction after the faulting read. Returning
354 // garbage from this read is ok.
355 thread->set_pending_unsafe_access_error();
356 uc->uc_mcontext.regs->nip = ((unsigned long)pc) + 4;
357 return true;
358 }
359 }
360 }
361
362 else { // thread->thread_state() != _thread_in_Java
363 if (sig == SIGILL && VM_Version::is_determine_features_test_running()) {
364 // SIGILL must be caused by VM_Version::determine_features().
365 *(int *)pc = 0; // patch instruction to 0 to indicate that it causes a SIGILL,
366 // flushing of icache is not necessary.
367 stub = pc + 4; // continue with next instruction.
368 }
369 else if (thread->thread_state() == _thread_in_vm &&
370 sig == SIGBUS && thread->doing_unsafe_access()) {
371 // We don't really need a stub here! Just set the pending exeption and
372 // continue at the next instruction after the faulting read. Returning
373 // garbage from this read is ok.
374 thread->set_pending_unsafe_access_error();
375 uc->uc_mcontext.regs->nip = ((unsigned long)pc) + 4;
376 return true;
377 }
378 }
379
380 // Check to see if we caught the safepoint code in the
381 // process of write protecting the memory serialization page.
382 // It write enables the page immediately after protecting it
383 // so we can just return to retry the write.
384 if ((sig == SIGSEGV) &&
385 // Si_addr may not be valid due to a bug in the linux-ppc64 kernel (see comment above).
386 // Use is_memory_serialization instead of si_addr.
387 ((NativeInstruction*)pc)->is_memory_serialization(thread, ucVoid)) {
388 // Synchronization problem in the pseudo memory barrier code (bug id 6546278)
389 // Block current thread until the memory serialize page permission restored.
390 os::block_on_serialize_page_trap();
391 return true;
392 }
393 }
394
395 if (stub != NULL) {
396 // Save all thread context in case we need to restore it.
397 if (thread != NULL) thread->set_saved_exception_pc(pc);
398 uc->uc_mcontext.regs->nip = (unsigned long)stub;
399 return true;
400 }
401
402 // signal-chaining
403 if (os::Linux::chained_handler(sig, info, ucVoid)) {
404 return true;
405 }
406
407 if (!abort_if_unrecognized) {
408 // caller wants another chance, so give it to him
409 return false;
410 }
411
412 if (pc == NULL && uc != NULL) {
413 pc = os::Linux::ucontext_get_pc(uc);
414 }
415
416 report_and_die:
417 // unmask current signal
418 sigset_t newset;
419 sigemptyset(&newset);
420 sigaddset(&newset, sig);
421 sigprocmask(SIG_UNBLOCK, &newset, NULL);
422
423 VMError err(t, sig, pc, info, ucVoid);
424 err.report_and_die();
425
426 ShouldNotReachHere();
427 return false;
428 }
429
430 void os::Linux::init_thread_fpu_state(void) {
431 // Disable FP exceptions.
432 __asm__ __volatile__ ("mtfsfi 6,0");
433 }
434
435 int os::Linux::get_fpu_control_word(void) {
436 // x86 has problems with FPU precision after pthread_cond_timedwait().
437 // nothing to do on ppc64.
438 return 0;
439 }
440
441 void os::Linux::set_fpu_control_word(int fpu_control) {
442 // x86 has problems with FPU precision after pthread_cond_timedwait().
443 // nothing to do on ppc64.
444 }
445
446 ////////////////////////////////////////////////////////////////////////////////
447 // thread stack
448
449 size_t os::Linux::min_stack_allowed = 768*K;
450
451 bool os::Linux::supports_variable_stack_size() { return true; }
452
453 // return default stack size for thr_type
454 size_t os::Linux::default_stack_size(os::ThreadType thr_type) {
455 // default stack size (compiler thread needs larger stack)
456 // Notice that the setting for compiler threads here have no impact
457 // because of the strange 'fallback logic' in os::create_thread().
458 // Better set CompilerThreadStackSize in globals_<os_cpu>.hpp if you want to
459 // specify a different stack size for compiler threads!
460 size_t s = (thr_type == os::compiler_thread ? 4 * M : 1024 * K);
461 return s;
462 }
463
464 size_t os::Linux::default_guard_size(os::ThreadType thr_type) {
465 return 2 * page_size();
466 }
467
468 // Java thread:
469 //
470 // Low memory addresses
471 // +------------------------+
472 // | |\ JavaThread created by VM does not have glibc
473 // | glibc guard page | - guard, attached Java thread usually has
474 // | |/ 1 page glibc guard.
475 // P1 +------------------------+ Thread::stack_base() - Thread::stack_size()
476 // | |\
477 // | HotSpot Guard Pages | - red and yellow pages
478 // | |/
479 // +------------------------+ JavaThread::stack_yellow_zone_base()
480 // | |\
481 // | Normal Stack | -
482 // | |/
483 // P2 +------------------------+ Thread::stack_base()
484 //
485 // Non-Java thread:
486 //
487 // Low memory addresses
488 // +------------------------+
489 // | |\
490 // | glibc guard page | - usually 1 page
491 // | |/
492 // P1 +------------------------+ Thread::stack_base() - Thread::stack_size()
493 // | |\
494 // | Normal Stack | -
495 // | |/
496 // P2 +------------------------+ Thread::stack_base()
497 //
498 // ** P1 (aka bottom) and size ( P2 = P1 - size) are the address and stack size returned from
499 // pthread_attr_getstack()
500
501 static void current_stack_region(address * bottom, size_t * size) {
502 if (os::Linux::is_initial_thread()) {
503 // initial thread needs special handling because pthread_getattr_np()
504 // may return bogus value.
505 *bottom = os::Linux::initial_thread_stack_bottom();
506 *size = os::Linux::initial_thread_stack_size();
507 } else {
508 pthread_attr_t attr;
509
510 int rslt = pthread_getattr_np(pthread_self(), &attr);
511
512 // JVM needs to know exact stack location, abort if it fails
513 if (rslt != 0) {
514 if (rslt == ENOMEM) {
515 vm_exit_out_of_memory(0, OOM_MMAP_ERROR, "pthread_getattr_np");
516 } else {
517 fatal(err_msg("pthread_getattr_np failed with errno = %d", rslt));
518 }
519 }
520
521 if (pthread_attr_getstack(&attr, (void **)bottom, size) != 0) {
522 fatal("Can not locate current stack attributes!");
523 }
524
525 pthread_attr_destroy(&attr);
526
527 }
528 assert(os::current_stack_pointer() >= *bottom &&
529 os::current_stack_pointer() < *bottom + *size, "just checking");
530 }
531
532 address os::current_stack_base() {
533 address bottom;
534 size_t size;
535 current_stack_region(&bottom, &size);
536 return (bottom + size);
537 }
538
539 size_t os::current_stack_size() {
540 // stack size includes normal stack and HotSpot guard pages
541 address bottom;
542 size_t size;
543 current_stack_region(&bottom, &size);
544 return size;
545 }
546
547 /////////////////////////////////////////////////////////////////////////////
548 // helper functions for fatal error handler
549
550 void os::print_context(outputStream *st, void *context) {
551 if (context == NULL) return;
552
553 ucontext_t* uc = (ucontext_t*)context;
554
555 st->print_cr("Registers:");
556 st->print("pc =" INTPTR_FORMAT " ", uc->uc_mcontext.regs->nip);
557 st->print("lr =" INTPTR_FORMAT " ", uc->uc_mcontext.regs->link);
558 st->print("ctr=" INTPTR_FORMAT " ", uc->uc_mcontext.regs->ctr);
559 st->cr();
560 for (int i = 0; i < 32; i++) {
561 st->print("r%-2d=" INTPTR_FORMAT " ", i, uc->uc_mcontext.regs->gpr[i]);
562 if (i % 3 == 2) st->cr();
563 }
564 st->cr();
565 st->cr();
566
567 intptr_t *sp = (intptr_t *)os::Linux::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::Linux::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
581 void os::print_register_info(outputStream *st, void *context) {
582 if (context == NULL) return;
583
584 ucontext_t *uc = (ucontext_t*)context;
585
586 st->print_cr("Register to memory mapping:");
587 st->cr();
588
589 // this is only for the "general purpose" registers
590 for (int i = 0; i < 32; i++) {
591 st->print("r%-2d=", i);
592 print_location(st, uc->uc_mcontext.regs->gpr[i]);
593 }
594 st->cr();
595 }
596
597 extern "C" {
598 int SpinPause() {
599 return 0;
600 }
601 }
602
603 #ifndef PRODUCT
604 void os::verify_stack_alignment() {
605 assert(((intptr_t)os::current_stack_pointer() & (StackAlignmentInBytes-1)) == 0, "incorrect stack alignment");
606 }
607 #endif