1 /*
2 * Copyright (c) 1999, 2016, Oracle and/or its affiliates. All rights reserved.
3 * Copyright (c) 2014, Red Hat Inc. 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 "asm/macroAssembler.hpp"
28 #include "classfile/classLoader.hpp"
29 #include "classfile/systemDictionary.hpp"
30 #include "classfile/vmSymbols.hpp"
31 #include "code/codeCache.hpp"
32 #include "code/icBuffer.hpp"
33 #include "code/vtableStubs.hpp"
34 #include "code/nativeInst.hpp"
35 #include "interpreter/interpreter.hpp"
36 #include "jvm_linux.h"
37 #include "memory/allocation.inline.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 #ifdef BUILTIN_SIM
57 #include "../../../../../../simulator/simulator.hpp"
58 #endif
59
60 // put OS-includes here
61 # include <sys/types.h>
62 # include <sys/mman.h>
63 # include <pthread.h>
64 # include <signal.h>
65 # include <errno.h>
66 # include <dlfcn.h>
67 # include <stdlib.h>
68 # include <stdio.h>
69 # include <unistd.h>
70 # include <sys/resource.h>
71 # include <pthread.h>
72 # include <sys/stat.h>
73 # include <sys/time.h>
74 # include <sys/utsname.h>
75 # include <sys/socket.h>
76 # include <sys/wait.h>
77 # include <pwd.h>
78 # include <poll.h>
79 # include <ucontext.h>
80 # include <fpu_control.h>
81
82 #ifdef BUILTIN_SIM
83 #define REG_SP REG_RSP
84 #define REG_PC REG_RIP
85 #define REG_FP REG_RBP
86 #define SPELL_REG_SP "rsp"
87 #define SPELL_REG_FP "rbp"
88 #else
89 #define REG_FP 29
90 #define REG_LR 30
91
92 #define SPELL_REG_SP "sp"
93 #define SPELL_REG_FP "x29"
94 #endif
95
96 address os::current_stack_pointer() {
97 register void *esp __asm__ (SPELL_REG_SP);
98 return (address) esp;
99 }
100
101 char* os::non_memory_address_word() {
102 // Must never look like an address returned by reserve_memory,
103 // even in its subfields (as defined by the CPU immediate fields,
104 // if the CPU splits constants across multiple instructions).
105
106 return (char*) 0xffffffffffff;
107 }
108
109 void os::initialize_thread(Thread *thr) {
110 }
111
112 address os::Linux::ucontext_get_pc(const ucontext_t * uc) {
113 #ifdef BUILTIN_SIM
114 return (address)uc->uc_mcontext.gregs[REG_PC];
115 #else
116 return (address)uc->uc_mcontext.pc;
117 #endif
118 }
119
120 void os::Linux::ucontext_set_pc(ucontext_t * uc, address pc) {
121 #ifdef BUILTIN_SIM
122 uc->uc_mcontext.gregs[REG_PC] = (intptr_t)pc;
123 #else
124 uc->uc_mcontext.pc = (intptr_t)pc;
125 #endif
126 }
127
128 intptr_t* os::Linux::ucontext_get_sp(const ucontext_t * uc) {
129 #ifdef BUILTIN_SIM
130 return (intptr_t*)uc->uc_mcontext.gregs[REG_SP];
131 #else
132 return (intptr_t*)uc->uc_mcontext.sp;
133 #endif
134 }
135
136 intptr_t* os::Linux::ucontext_get_fp(const ucontext_t * uc) {
137 #ifdef BUILTIN_SIM
138 return (intptr_t*)uc->uc_mcontext.gregs[REG_FP];
139 #else
140 return (intptr_t*)uc->uc_mcontext.regs[REG_FP];
141 #endif
142 }
143
144 // For Forte Analyzer AsyncGetCallTrace profiling support - thread
145 // is currently interrupted by SIGPROF.
146 // os::Solaris::fetch_frame_from_ucontext() tries to skip nested signal
147 // frames. Currently we don't do that on Linux, so it's the same as
148 // os::fetch_frame_from_context().
149 ExtendedPC os::Linux::fetch_frame_from_ucontext(Thread* thread,
150 const ucontext_t* uc, intptr_t** ret_sp, intptr_t** ret_fp) {
151
152 assert(thread != NULL, "just checking");
153 assert(ret_sp != NULL, "just checking");
154 assert(ret_fp != NULL, "just checking");
155
156 return os::fetch_frame_from_context(uc, ret_sp, ret_fp);
157 }
158
159 ExtendedPC os::fetch_frame_from_context(const void* ucVoid,
160 intptr_t** ret_sp, intptr_t** ret_fp) {
161
162 ExtendedPC epc;
163 const ucontext_t* uc = (const ucontext_t*)ucVoid;
164
165 if (uc != NULL) {
166 epc = ExtendedPC(os::Linux::ucontext_get_pc(uc));
167 if (ret_sp) *ret_sp = os::Linux::ucontext_get_sp(uc);
168 if (ret_fp) *ret_fp = os::Linux::ucontext_get_fp(uc);
169 } else {
170 // construct empty ExtendedPC for return value checking
171 epc = ExtendedPC(NULL);
172 if (ret_sp) *ret_sp = (intptr_t *)NULL;
173 if (ret_fp) *ret_fp = (intptr_t *)NULL;
174 }
175
176 return epc;
177 }
178
179 frame os::fetch_frame_from_context(const void* ucVoid) {
180 intptr_t* sp;
181 intptr_t* fp;
182 ExtendedPC epc = fetch_frame_from_context(ucVoid, &sp, &fp);
183 return frame(sp, fp, epc.pc());
184 }
185
186 bool os::Linux::get_frame_at_stack_banging_point(JavaThread* thread, ucontext_t* uc, frame* fr) {
187 address pc = (address) os::Linux::ucontext_get_pc(uc);
188 if (Interpreter::contains(pc)) {
189 // interpreter performs stack banging after the fixed frame header has
190 // been generated while the compilers perform it before. To maintain
191 // semantic consistency between interpreted and compiled frames, the
192 // method returns the Java sender of the current frame.
193 *fr = os::fetch_frame_from_context(uc);
194 if (!fr->is_first_java_frame()) {
195 assert(fr->safe_for_sender(thread), "Safety check");
196 *fr = fr->java_sender();
197 }
198 } else {
199 // more complex code with compiled code
200 assert(!Interpreter::contains(pc), "Interpreted methods should have been handled above");
201 CodeBlob* cb = CodeCache::find_blob(pc);
202 if (cb == NULL || !cb->is_nmethod() || cb->is_frame_complete_at(pc)) {
203 // Not sure where the pc points to, fallback to default
204 // stack overflow handling
205 return false;
206 } else {
207 // In compiled code, the stack banging is performed before LR
208 // has been saved in the frame. LR is live, and SP and FP
209 // belong to the caller.
210 intptr_t* fp = os::Linux::ucontext_get_fp(uc);
211 intptr_t* sp = os::Linux::ucontext_get_sp(uc);
212 void* pc = (void*)(uc->uc_mcontext.regs[REG_LR]
213 - NativeInstruction::instruction_size);
214 *fr = frame(sp, fp, pc);
215 if (!fr->is_java_frame()) {
216 assert(fr->safe_for_sender(thread), "Safety check");
217 assert(!fr->is_first_frame(), "Safety check");
218 *fr = fr->java_sender();
219 }
220 }
221 }
222 assert(fr->is_java_frame(), "Safety check");
223 return true;
224 }
225
226 // By default, gcc always saves frame pointer rfp on this stack. This
227 // may get turned off by -fomit-frame-pointer.
228 frame os::get_sender_for_C_frame(frame* fr) {
229 #ifdef BUILTIN_SIM
230 return frame(fr->sender_sp(), fr->link(), fr->sender_pc());
231 #else
232 return frame(fr->link(), fr->link(), fr->sender_pc());
233 #endif
234 }
235
236 intptr_t* _get_previous_fp() {
237 register intptr_t **ebp __asm__ (SPELL_REG_FP);
238 return (intptr_t*) *ebp; // we want what it points to.
239 }
240
241
242 frame os::current_frame() {
243 intptr_t* fp = _get_previous_fp();
244 frame myframe((intptr_t*)os::current_stack_pointer(),
245 (intptr_t*)fp,
246 CAST_FROM_FN_PTR(address, os::current_frame));
247 if (os::is_first_C_frame(&myframe)) {
248 // stack is not walkable
249 return frame();
250 } else {
251 return os::get_sender_for_C_frame(&myframe);
252 }
253 }
254
255 // Utility functions
256
257 // From IA32 System Programming Guide
258 enum {
259 trap_page_fault = 0xE
260 };
261
262 #ifdef BUILTIN_SIM
263 extern "C" void Fetch32PFI () ;
264 extern "C" void Fetch32Resume () ;
265 extern "C" void FetchNPFI () ;
266 extern "C" void FetchNResume () ;
267 #endif
268
269 extern "C" JNIEXPORT int
270 JVM_handle_linux_signal(int sig,
271 siginfo_t* info,
272 void* ucVoid,
273 int abort_if_unrecognized) {
274 ucontext_t* uc = (ucontext_t*) ucVoid;
275
276 Thread* t = Thread::current_or_null_safe();
277
278 // Must do this before SignalHandlerMark, if crash protection installed we will longjmp away
279 // (no destructors can be run)
280 os::WatcherThreadCrashProtection::check_crash_protection(sig, t);
281
282 SignalHandlerMark shm(t);
283
284 // Note: it's not uncommon that JNI code uses signal/sigset to install
285 // then restore certain signal handler (e.g. to temporarily block SIGPIPE,
286 // or have a SIGILL handler when detecting CPU type). When that happens,
287 // JVM_handle_linux_signal() might be invoked with junk info/ucVoid. To
288 // avoid unnecessary crash when libjsig is not preloaded, try handle signals
289 // that do not require siginfo/ucontext first.
290
291 if (sig == SIGPIPE || sig == SIGXFSZ) {
292 // allow chained handler to go first
293 if (os::Linux::chained_handler(sig, info, ucVoid)) {
294 return true;
295 } else {
296 // Ignoring SIGPIPE/SIGXFSZ - see bugs 4229104 or 6499219
297 return true;
298 }
299 }
300
301 JavaThread* thread = NULL;
302 VMThread* vmthread = NULL;
303 if (os::Linux::signal_handlers_are_installed) {
304 if (t != NULL ){
305 if(t->is_Java_thread()) {
306 thread = (JavaThread*)t;
307 }
308 else if(t->is_VM_thread()){
309 vmthread = (VMThread *)t;
310 }
311 }
312 }
313 /*
314 NOTE: does not seem to work on linux.
315 if (info == NULL || info->si_code <= 0 || info->si_code == SI_NOINFO) {
316 // can't decode this kind of signal
317 info = NULL;
318 } else {
319 assert(sig == info->si_signo, "bad siginfo");
320 }
321 */
322 // decide if this trap can be handled by a stub
323 address stub = NULL;
324
325 address pc = NULL;
326
327 //%note os_trap_1
328 if (info != NULL && uc != NULL && thread != NULL) {
329 pc = (address) os::Linux::ucontext_get_pc(uc);
330
331 #ifdef BUILTIN_SIM
332 if (pc == (address) Fetch32PFI) {
333 uc->uc_mcontext.gregs[REG_PC] = intptr_t(Fetch32Resume) ;
334 return 1 ;
335 }
336 if (pc == (address) FetchNPFI) {
337 uc->uc_mcontext.gregs[REG_PC] = intptr_t (FetchNResume) ;
338 return 1 ;
339 }
340 #else
341 if (StubRoutines::is_safefetch_fault(pc)) {
342 os::Linux::ucontext_set_pc(uc, StubRoutines::continuation_for_safefetch_fault(pc));
343 return 1;
344 }
345 #endif
346
347 // Handle ALL stack overflow variations here
348 if (sig == SIGSEGV) {
349 address addr = (address) info->si_addr;
350
351 // check if fault address is within thread stack
352 if (thread->on_local_stack(addr)) {
353 // stack overflow
354 if (thread->in_stack_yellow_reserved_zone(addr)) {
355 thread->disable_stack_yellow_reserved_zone();
356 if (thread->thread_state() == _thread_in_Java) {
357 if (thread->in_stack_reserved_zone(addr)) {
358 frame fr;
359 if (os::Linux::get_frame_at_stack_banging_point(thread, uc, &fr)) {
360 assert(fr.is_java_frame(), "Must be a Java frame");
361 frame activation =
362 SharedRuntime::look_for_reserved_stack_annotated_method(thread, fr);
363 if (activation.sp() != NULL) {
364 thread->disable_stack_reserved_zone();
365 if (activation.is_interpreted_frame()) {
366 thread->set_reserved_stack_activation((address)(
367 activation.fp() + frame::interpreter_frame_initial_sp_offset));
368 } else {
369 thread->set_reserved_stack_activation((address)activation.unextended_sp());
370 }
371 return 1;
372 }
373 }
374 }
375 // Throw a stack overflow exception. Guard pages will be reenabled
376 // while unwinding the stack.
377 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::STACK_OVERFLOW);
378 } else {
379 // Thread was in the vm or native code. Return and try to finish.
380 return 1;
381 }
382 } else if (thread->in_stack_red_zone(addr)) {
383 // Fatal red zone violation. Disable the guard pages and fall through
384 // to handle_unexpected_exception way down below.
385 thread->disable_stack_red_zone();
386 tty->print_raw_cr("An irrecoverable stack overflow has occurred.");
387
388 // This is a likely cause, but hard to verify. Let's just print
389 // it as a hint.
390 tty->print_raw_cr("Please check if any of your loaded .so files has "
391 "enabled executable stack (see man page execstack(8))");
392 } else {
393 // Accessing stack address below sp may cause SEGV if current
394 // thread has MAP_GROWSDOWN stack. This should only happen when
395 // current thread was created by user code with MAP_GROWSDOWN flag
396 // and then attached to VM. See notes in os_linux.cpp.
397 if (thread->osthread()->expanding_stack() == 0) {
398 thread->osthread()->set_expanding_stack();
399 if (os::Linux::manually_expand_stack(thread, addr)) {
400 thread->osthread()->clear_expanding_stack();
401 return 1;
402 }
403 thread->osthread()->clear_expanding_stack();
404 } else {
405 fatal("recursive segv. expanding stack.");
406 }
407 }
408 }
409 }
410
411 if (thread->thread_state() == _thread_in_Java) {
412 // Java thread running in Java code => find exception handler if any
413 // a fault inside compiled code, the interpreter, or a stub
414
415 // Handle signal from NativeJump::patch_verified_entry().
416 if ((sig == SIGILL || sig == SIGTRAP)
417 && nativeInstruction_at(pc)->is_sigill_zombie_not_entrant()) {
418 if (TraceTraps) {
419 tty->print_cr("trap: zombie_not_entrant (%s)", (sig == SIGTRAP) ? "SIGTRAP" : "SIGILL");
420 }
421 stub = SharedRuntime::get_handle_wrong_method_stub();
422 } else if (sig == SIGSEGV && os::is_poll_address((address)info->si_addr)) {
423 stub = SharedRuntime::get_poll_stub(pc);
424 } else if (sig == SIGBUS /* && info->si_code == BUS_OBJERR */) {
425 // BugId 4454115: A read from a MappedByteBuffer can fault
426 // here if the underlying file has been truncated.
427 // Do not crash the VM in such a case.
428 CodeBlob* cb = CodeCache::find_blob_unsafe(pc);
429 CompiledMethod* nm = (cb != NULL) ? cb->as_compiled_method_or_null() : NULL;
430 if (nm != NULL && nm->has_unsafe_access()) {
431 address next_pc = pc + NativeCall::instruction_size;
432 stub = SharedRuntime::handle_unsafe_access(thread, next_pc);
433 }
434 }
435 else
436
437 if (sig == SIGFPE &&
438 (info->si_code == FPE_INTDIV || info->si_code == FPE_FLTDIV)) {
439 stub =
440 SharedRuntime::
441 continuation_for_implicit_exception(thread,
442 pc,
443 SharedRuntime::
444 IMPLICIT_DIVIDE_BY_ZERO);
445 } else if (sig == SIGSEGV &&
446 !MacroAssembler::needs_explicit_null_check((intptr_t)info->si_addr)) {
447 // Determination of interpreter/vtable stub/compiled code null exception
448 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL);
449 }
450 } else if (thread->thread_state() == _thread_in_vm &&
451 sig == SIGBUS && /* info->si_code == BUS_OBJERR && */
452 thread->doing_unsafe_access()) {
453 address next_pc = pc + NativeCall::instruction_size;
454 stub = SharedRuntime::handle_unsafe_access(thread, next_pc);
455 }
456
457 // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC kicks in
458 // and the heap gets shrunk before the field access.
459 if ((sig == SIGSEGV) || (sig == SIGBUS)) {
460 address addr = JNI_FastGetField::find_slowcase_pc(pc);
461 if (addr != (address)-1) {
462 stub = addr;
463 }
464 }
465
466 // Check to see if we caught the safepoint code in the
467 // process of write protecting the memory serialization page.
468 // It write enables the page immediately after protecting it
469 // so we can just return to retry the write.
470 if ((sig == SIGSEGV) &&
471 os::is_memory_serialize_page(thread, (address) info->si_addr)) {
472 // Block current thread until the memory serialize page permission restored.
473 os::block_on_serialize_page_trap();
474 return true;
475 }
476 }
477
478 if (stub != NULL) {
479 // save all thread context in case we need to restore it
480 if (thread != NULL) thread->set_saved_exception_pc(pc);
481
482 os::Linux::ucontext_set_pc(uc, stub);
483 return true;
484 }
485
486 // signal-chaining
487 if (os::Linux::chained_handler(sig, info, ucVoid)) {
488 return true;
489 }
490
491 if (!abort_if_unrecognized) {
492 // caller wants another chance, so give it to him
493 return false;
494 }
495
496 if (pc == NULL && uc != NULL) {
497 pc = os::Linux::ucontext_get_pc(uc);
498 }
499
500 // unmask current signal
501 sigset_t newset;
502 sigemptyset(&newset);
503 sigaddset(&newset, sig);
504 sigprocmask(SIG_UNBLOCK, &newset, NULL);
505
506 VMError::report_and_die(t, sig, pc, info, ucVoid);
507
508 ShouldNotReachHere();
509 return true; // Mute compiler
510 }
511
512 void os::Linux::init_thread_fpu_state(void) {
513 }
514
515 int os::Linux::get_fpu_control_word(void) {
516 return 0;
517 }
518
519 void os::Linux::set_fpu_control_word(int fpu_control) {
520 }
521
522 // Check that the linux kernel version is 2.4 or higher since earlier
523 // versions do not support SSE without patches.
524 bool os::supports_sse() {
525 return true;
526 }
527
528 bool os::is_allocatable(size_t bytes) {
529 return true;
530 }
531
532 ////////////////////////////////////////////////////////////////////////////////
533 // thread stack
534
535 // Minimum usable stack sizes required to get to user code. Space for
536 // HotSpot guard pages is added later.
537 size_t os::Posix::_compiler_thread_min_stack_allowed = 32 * K;
538 size_t os::Posix::_java_thread_min_stack_allowed = 32 * K;
539 size_t os::Posix::_vm_internal_thread_min_stack_allowed = 64 * K;
540
541 // return default stack size for thr_type
542 size_t os::Posix::default_stack_size(os::ThreadType thr_type) {
543 // default stack size (compiler thread needs larger stack)
544 size_t s = (thr_type == os::compiler_thread ? 4 * M : 1 * M);
545 return s;
546 }
547
548 /////////////////////////////////////////////////////////////////////////////
549 // helper functions for fatal error handler
550
551 void os::print_context(outputStream *st, const void *context) {
552 if (context == NULL) return;
553
554 const ucontext_t *uc = (const ucontext_t*)context;
555 st->print_cr("Registers:");
556 #ifdef BUILTIN_SIM
557 st->print( "RAX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RAX]);
558 st->print(", RBX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RBX]);
559 st->print(", RCX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RCX]);
560 st->print(", RDX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RDX]);
561 st->cr();
562 st->print( "RSP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RSP]);
563 st->print(", RBP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RBP]);
564 st->print(", RSI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RSI]);
565 st->print(", RDI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RDI]);
566 st->cr();
567 st->print( "R8 =" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R8]);
568 st->print(", R9 =" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R9]);
569 st->print(", R10=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R10]);
570 st->print(", R11=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R11]);
571 st->cr();
572 st->print( "R12=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R12]);
573 st->print(", R13=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R13]);
574 st->print(", R14=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R14]);
575 st->print(", R15=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R15]);
576 st->cr();
577 st->print( "RIP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RIP]);
578 st->print(", EFLAGS=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_EFL]);
579 st->print(", CSGSFS=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_CSGSFS]);
580 st->print(", ERR=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_ERR]);
581 st->cr();
582 st->print(" TRAPNO=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_TRAPNO]);
583 st->cr();
584 #else
585 for (int r = 0; r < 31; r++) {
586 st->print("R%-2d=", r);
587 print_location(st, uc->uc_mcontext.regs[r]);
588 }
589 #endif
590 st->cr();
591
592 intptr_t *sp = (intptr_t *)os::Linux::ucontext_get_sp(uc);
593 st->print_cr("Top of Stack: (sp=" PTR_FORMAT ")", p2i(sp));
594 print_hex_dump(st, (address)sp, (address)(sp + 8*sizeof(intptr_t)), sizeof(intptr_t));
595 st->cr();
596
597 // Note: it may be unsafe to inspect memory near pc. For example, pc may
598 // point to garbage if entry point in an nmethod is corrupted. Leave
599 // this at the end, and hope for the best.
600 address pc = os::Linux::ucontext_get_pc(uc);
601 st->print_cr("Instructions: (pc=" PTR_FORMAT ")", p2i(pc));
602 print_hex_dump(st, pc - 32, pc + 32, sizeof(char));
603 }
604
605 void os::print_register_info(outputStream *st, const void *context) {
606 if (context == NULL) return;
607
608 const ucontext_t *uc = (const ucontext_t*)context;
609
610 st->print_cr("Register to memory mapping:");
611 st->cr();
612
613 // this is horrendously verbose but the layout of the registers in the
614 // context does not match how we defined our abstract Register set, so
615 // we can't just iterate through the gregs area
616
617 // this is only for the "general purpose" registers
618
619 #ifdef BUILTIN_SIM
620 st->print("RAX="); print_location(st, uc->uc_mcontext.gregs[REG_RAX]);
621 st->print("RBX="); print_location(st, uc->uc_mcontext.gregs[REG_RBX]);
622 st->print("RCX="); print_location(st, uc->uc_mcontext.gregs[REG_RCX]);
623 st->print("RDX="); print_location(st, uc->uc_mcontext.gregs[REG_RDX]);
624 st->print("RSP="); print_location(st, uc->uc_mcontext.gregs[REG_RSP]);
625 st->print("RBP="); print_location(st, uc->uc_mcontext.gregs[REG_RBP]);
626 st->print("RSI="); print_location(st, uc->uc_mcontext.gregs[REG_RSI]);
627 st->print("RDI="); print_location(st, uc->uc_mcontext.gregs[REG_RDI]);
628 st->print("R8 ="); print_location(st, uc->uc_mcontext.gregs[REG_R8]);
629 st->print("R9 ="); print_location(st, uc->uc_mcontext.gregs[REG_R9]);
630 st->print("R10="); print_location(st, uc->uc_mcontext.gregs[REG_R10]);
631 st->print("R11="); print_location(st, uc->uc_mcontext.gregs[REG_R11]);
632 st->print("R12="); print_location(st, uc->uc_mcontext.gregs[REG_R12]);
633 st->print("R13="); print_location(st, uc->uc_mcontext.gregs[REG_R13]);
634 st->print("R14="); print_location(st, uc->uc_mcontext.gregs[REG_R14]);
635 st->print("R15="); print_location(st, uc->uc_mcontext.gregs[REG_R15]);
636 #else
637 for (int r = 0; r < 31; r++)
638 st->print_cr( "R%d=" INTPTR_FORMAT, r, (uintptr_t)uc->uc_mcontext.regs[r]);
639 #endif
640 st->cr();
641 }
642
643 void os::setup_fpu() {
644 }
645
646 #ifndef PRODUCT
647 void os::verify_stack_alignment() {
648 assert(((intptr_t)os::current_stack_pointer() & (StackAlignmentInBytes-1)) == 0, "incorrect stack alignment");
649 }
650 #endif
651
652 int os::extra_bang_size_in_bytes() {
653 // AArch64 does not require the additional stack bang.
654 return 0;
655 }
656
657 extern "C" {
658 int SpinPause() {
659 return 0;
660 }
661
662 void _Copy_conjoint_jshorts_atomic(jshort* from, jshort* to, size_t count) {
663 if (from > to) {
664 jshort *end = from + count;
665 while (from < end)
666 *(to++) = *(from++);
667 }
668 else if (from < to) {
669 jshort *end = from;
670 from += count - 1;
671 to += count - 1;
672 while (from >= end)
673 *(to--) = *(from--);
674 }
675 }
676 void _Copy_conjoint_jints_atomic(jint* from, jint* to, size_t count) {
677 if (from > to) {
678 jint *end = from + count;
679 while (from < end)
680 *(to++) = *(from++);
681 }
682 else if (from < to) {
683 jint *end = from;
684 from += count - 1;
685 to += count - 1;
686 while (from >= end)
687 *(to--) = *(from--);
688 }
689 }
690 void _Copy_conjoint_jlongs_atomic(jlong* from, jlong* to, size_t count) {
691 if (from > to) {
692 jlong *end = from + count;
693 while (from < end)
694 os::atomic_copy64(from++, to++);
695 }
696 else if (from < to) {
697 jlong *end = from;
698 from += count - 1;
699 to += count - 1;
700 while (from >= end)
701 os::atomic_copy64(from--, to--);
702 }
703 }
704
705 void _Copy_arrayof_conjoint_bytes(HeapWord* from,
706 HeapWord* to,
707 size_t count) {
708 memmove(to, from, count);
709 }
710 void _Copy_arrayof_conjoint_jshorts(HeapWord* from,
711 HeapWord* to,
712 size_t count) {
713 memmove(to, from, count * 2);
714 }
715 void _Copy_arrayof_conjoint_jints(HeapWord* from,
716 HeapWord* to,
717 size_t count) {
718 memmove(to, from, count * 4);
719 }
720 void _Copy_arrayof_conjoint_jlongs(HeapWord* from,
721 HeapWord* to,
722 size_t count) {
723 memmove(to, from, count * 8);
724 }
725 };