os_linux_ppc.cpp revision 9743:d6c6ee9d40b0
1/* 2 * Copyright (c) 1997, 2015, Oracle and/or its affiliates. All rights reserved. 3 * Copyright 2012, 2015 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 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 "assembler_ppc.inline.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 "interpreter/interpreter.hpp" 35#include "jvm_linux.h" 36#include "memory/allocation.inline.hpp" 37#include "mutex_linux.inline.hpp" 38#include "nativeInst_ppc.hpp" 39#include "os_share_linux.hpp" 40#include "prims/jniFastGetField.hpp" 41#include "prims/jvm.h" 42#include "prims/jvm_misc.hpp" 43#include "runtime/arguments.hpp" 44#include "runtime/extendedPC.hpp" 45#include "runtime/frame.inline.hpp" 46#include "runtime/interfaceSupport.hpp" 47#include "runtime/java.hpp" 48#include "runtime/javaCalls.hpp" 49#include "runtime/mutexLocker.hpp" 50#include "runtime/osThread.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 58// put OS-includes here 59# include <sys/types.h> 60# include <sys/mman.h> 61# include <pthread.h> 62# include <signal.h> 63# include <errno.h> 64# include <dlfcn.h> 65# include <stdlib.h> 66# include <stdio.h> 67# include <unistd.h> 68# include <sys/resource.h> 69# include <pthread.h> 70# include <sys/stat.h> 71# include <sys/time.h> 72# include <sys/utsname.h> 73# include <sys/socket.h> 74# include <sys/wait.h> 75# include <pwd.h> 76# include <poll.h> 77# include <ucontext.h> 78 79 80address os::current_stack_pointer() { 81 intptr_t* csp; 82 83 // inline assembly `mr regno(csp), R1_SP': 84 __asm__ __volatile__ ("mr %0, 1":"=r"(csp):); 85 86 return (address) csp; 87} 88 89char* os::non_memory_address_word() { 90 // Must never look like an address returned by reserve_memory, 91 // even in its subfields (as defined by the CPU immediate fields, 92 // if the CPU splits constants across multiple instructions). 93 94 return (char*) -1; 95} 96 97void os::initialize_thread(Thread *thread) { } 98 99// Frame information (pc, sp, fp) retrieved via ucontext 100// always looks like a C-frame according to the frame 101// conventions in frame_ppc64.hpp. 102address os::Linux::ucontext_get_pc(const ucontext_t * uc) { 103 // On powerpc64, ucontext_t is not selfcontained but contains 104 // a pointer to an optional substructure (mcontext_t.regs) containing the volatile 105 // registers - NIP, among others. 106 // This substructure may or may not be there depending where uc came from: 107 // - if uc was handed over as the argument to a sigaction handler, a pointer to the 108 // substructure was provided by the kernel when calling the signal handler, and 109 // regs->nip can be accessed. 110 // - if uc was filled by getcontext(), it is undefined - getcontext() does not fill 111 // it because the volatile registers are not needed to make setcontext() work. 112 // Hopefully it was zero'd out beforehand. 113 guarantee(uc->uc_mcontext.regs != NULL, "only use ucontext_get_pc in sigaction context"); 114 return (address)uc->uc_mcontext.regs->nip; 115} 116 117// modify PC in ucontext. 118// Note: Only use this for an ucontext handed down to a signal handler. See comment 119// in ucontext_get_pc. 120void os::Linux::ucontext_set_pc(ucontext_t * uc, address pc) { 121 guarantee(uc->uc_mcontext.regs != NULL, "only use ucontext_set_pc in sigaction context"); 122 uc->uc_mcontext.regs->nip = (unsigned long)pc; 123} 124 125intptr_t* os::Linux::ucontext_get_sp(const ucontext_t * uc) { 126 return (intptr_t*)uc->uc_mcontext.regs->gpr[1/*REG_SP*/]; 127} 128 129intptr_t* os::Linux::ucontext_get_fp(const ucontext_t * uc) { 130 return NULL; 131} 132 133ExtendedPC os::fetch_frame_from_context(const void* ucVoid, 134 intptr_t** ret_sp, intptr_t** ret_fp) { 135 136 ExtendedPC epc; 137 const ucontext_t* uc = (const ucontext_t*)ucVoid; 138 139 if (uc != NULL) { 140 epc = ExtendedPC(os::Linux::ucontext_get_pc(uc)); 141 if (ret_sp) *ret_sp = os::Linux::ucontext_get_sp(uc); 142 if (ret_fp) *ret_fp = os::Linux::ucontext_get_fp(uc); 143 } else { 144 // construct empty ExtendedPC for return value checking 145 epc = ExtendedPC(NULL); 146 if (ret_sp) *ret_sp = (intptr_t *)NULL; 147 if (ret_fp) *ret_fp = (intptr_t *)NULL; 148 } 149 150 return epc; 151} 152 153frame os::fetch_frame_from_context(const void* ucVoid) { 154 intptr_t* sp; 155 intptr_t* fp; 156 ExtendedPC epc = fetch_frame_from_context(ucVoid, &sp, &fp); 157 return frame(sp, epc.pc()); 158} 159 160frame os::get_sender_for_C_frame(frame* fr) { 161 if (*fr->sp() == 0) { 162 // fr is the last C frame 163 return frame(NULL, NULL); 164 } 165 return frame(fr->sender_sp(), fr->sender_pc()); 166} 167 168 169frame os::current_frame() { 170 intptr_t* csp = (intptr_t*) *((intptr_t*) os::current_stack_pointer()); 171 // hack. 172 frame topframe(csp, (address)0x8); 173 // return sender of current topframe which hopefully has pc != NULL. 174 return os::get_sender_for_C_frame(&topframe); 175} 176 177// Utility functions 178 179extern "C" JNIEXPORT int 180JVM_handle_linux_signal(int sig, 181 siginfo_t* info, 182 void* ucVoid, 183 int abort_if_unrecognized) { 184 ucontext_t* uc = (ucontext_t*) ucVoid; 185 186 Thread* t = Thread::current_or_null_safe(); 187 188 SignalHandlerMark shm(t); 189 190 // Note: it's not uncommon that JNI code uses signal/sigset to install 191 // then restore certain signal handler (e.g. to temporarily block SIGPIPE, 192 // or have a SIGILL handler when detecting CPU type). When that happens, 193 // JVM_handle_linux_signal() might be invoked with junk info/ucVoid. To 194 // avoid unnecessary crash when libjsig is not preloaded, try handle signals 195 // that do not require siginfo/ucontext first. 196 197 if (sig == SIGPIPE) { 198 if (os::Linux::chained_handler(sig, info, ucVoid)) { 199 return true; 200 } else { 201 if (PrintMiscellaneous && (WizardMode || Verbose)) { 202 warning("Ignoring SIGPIPE - see bug 4229104"); 203 } 204 return true; 205 } 206 } 207 208 JavaThread* thread = NULL; 209 VMThread* vmthread = NULL; 210 if (os::Linux::signal_handlers_are_installed) { 211 if (t != NULL) { 212 if(t->is_Java_thread()) { 213 thread = (JavaThread*)t; 214 } else if(t->is_VM_thread()) { 215 vmthread = (VMThread *)t; 216 } 217 } 218 } 219 220 // Moved SafeFetch32 handling outside thread!=NULL conditional block to make 221 // it work if no associated JavaThread object exists. 222 if (uc) { 223 address const pc = os::Linux::ucontext_get_pc(uc); 224 if (pc && StubRoutines::is_safefetch_fault(pc)) { 225 os::Linux::ucontext_set_pc(uc, StubRoutines::continuation_for_safefetch_fault(pc)); 226 return true; 227 } 228 } 229 230 // decide if this trap can be handled by a stub 231 address stub = NULL; 232 address pc = NULL; 233 234 //%note os_trap_1 235 if (info != NULL && uc != NULL && thread != NULL) { 236 pc = (address) os::Linux::ucontext_get_pc(uc); 237 238 // Handle ALL stack overflow variations here 239 if (sig == SIGSEGV) { 240 // Si_addr may not be valid due to a bug in the linux-ppc64 kernel (see 241 // comment below). Use get_stack_bang_address instead of si_addr. 242 address addr = ((NativeInstruction*)pc)->get_stack_bang_address(uc); 243 244 // Check if fault address is within thread stack. 245 if (addr < thread->stack_base() && 246 addr >= thread->stack_base() - thread->stack_size()) { 247 // stack overflow 248 if (thread->in_stack_yellow_zone(addr)) { 249 thread->disable_stack_yellow_zone(); 250 if (thread->thread_state() == _thread_in_Java) { 251 // Throw a stack overflow exception. 252 // Guard pages will be reenabled while unwinding the stack. 253 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::STACK_OVERFLOW); 254 } else { 255 // Thread was in the vm or native code. Return and try to finish. 256 return 1; 257 } 258 } else if (thread->in_stack_red_zone(addr)) { 259 // Fatal red zone violation. Disable the guard pages and fall through 260 // to handle_unexpected_exception way down below. 261 thread->disable_stack_red_zone(); 262 tty->print_raw_cr("An irrecoverable stack overflow has occurred."); 263 264 // This is a likely cause, but hard to verify. Let's just print 265 // it as a hint. 266 tty->print_raw_cr("Please check if any of your loaded .so files has " 267 "enabled executable stack (see man page execstack(8))"); 268 } else { 269 // Accessing stack address below sp may cause SEGV if current 270 // thread has MAP_GROWSDOWN stack. This should only happen when 271 // current thread was created by user code with MAP_GROWSDOWN flag 272 // and then attached to VM. See notes in os_linux.cpp. 273 if (thread->osthread()->expanding_stack() == 0) { 274 thread->osthread()->set_expanding_stack(); 275 if (os::Linux::manually_expand_stack(thread, addr)) { 276 thread->osthread()->clear_expanding_stack(); 277 return 1; 278 } 279 thread->osthread()->clear_expanding_stack(); 280 } else { 281 fatal("recursive segv. expanding stack."); 282 } 283 } 284 } 285 } 286 287 if (thread->thread_state() == _thread_in_Java) { 288 // Java thread running in Java code => find exception handler if any 289 // a fault inside compiled code, the interpreter, or a stub 290 291 // A VM-related SIGILL may only occur if we are not in the zero page. 292 // On AIX, we get a SIGILL if we jump to 0x0 or to somewhere else 293 // in the zero page, because it is filled with 0x0. We ignore 294 // explicit SIGILLs in the zero page. 295 if (sig == SIGILL && (pc < (address) 0x200)) { 296 if (TraceTraps) { 297 tty->print_raw_cr("SIGILL happened inside zero page."); 298 } 299 goto report_and_die; 300 } 301 302 CodeBlob *cb = NULL; 303 // Handle signal from NativeJump::patch_verified_entry(). 304 if (( TrapBasedNotEntrantChecks && sig == SIGTRAP && nativeInstruction_at(pc)->is_sigtrap_zombie_not_entrant()) || 305 (!TrapBasedNotEntrantChecks && sig == SIGILL && nativeInstruction_at(pc)->is_sigill_zombie_not_entrant())) { 306 if (TraceTraps) { 307 tty->print_cr("trap: zombie_not_entrant (%s)", (sig == SIGTRAP) ? "SIGTRAP" : "SIGILL"); 308 } 309 stub = SharedRuntime::get_handle_wrong_method_stub(); 310 } 311 312 else if (sig == SIGSEGV && 313 // A linux-ppc64 kernel before 2.6.6 doesn't set si_addr on some segfaults 314 // in 64bit mode (cf. http://www.kernel.org/pub/linux/kernel/v2.6/ChangeLog-2.6.6), 315 // especially when we try to read from the safepoint polling page. So the check 316 // (address)info->si_addr == os::get_standard_polling_page() 317 // doesn't work for us. We use: 318 ((NativeInstruction*)pc)->is_safepoint_poll() && 319 CodeCache::contains((void*) pc) && 320 ((cb = CodeCache::find_blob(pc)) != NULL) && 321 cb->is_nmethod()) { 322 if (TraceTraps) { 323 tty->print_cr("trap: safepoint_poll at " INTPTR_FORMAT " (SIGSEGV)", p2i(pc)); 324 } 325 stub = SharedRuntime::get_poll_stub(pc); 326 } 327 328 // SIGTRAP-based ic miss check in compiled code. 329 else if (sig == SIGTRAP && TrapBasedICMissChecks && 330 nativeInstruction_at(pc)->is_sigtrap_ic_miss_check()) { 331 if (TraceTraps) { 332 tty->print_cr("trap: ic_miss_check at " INTPTR_FORMAT " (SIGTRAP)", p2i(pc)); 333 } 334 stub = SharedRuntime::get_ic_miss_stub(); 335 } 336 337 // SIGTRAP-based implicit null check in compiled code. 338 else if (sig == SIGTRAP && TrapBasedNullChecks && 339 nativeInstruction_at(pc)->is_sigtrap_null_check()) { 340 if (TraceTraps) { 341 tty->print_cr("trap: null_check at " INTPTR_FORMAT " (SIGTRAP)", p2i(pc)); 342 } 343 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL); 344 } 345 346 // SIGSEGV-based implicit null check in compiled code. 347 else if (sig == SIGSEGV && ImplicitNullChecks && 348 CodeCache::contains((void*) pc) && 349 !MacroAssembler::needs_explicit_null_check((intptr_t) info->si_addr)) { 350 if (TraceTraps) { 351 tty->print_cr("trap: null_check at " INTPTR_FORMAT " (SIGSEGV)", p2i(pc)); 352 } 353 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL); 354 } 355 356#ifdef COMPILER2 357 // SIGTRAP-based implicit range check in compiled code. 358 else if (sig == SIGTRAP && TrapBasedRangeChecks && 359 nativeInstruction_at(pc)->is_sigtrap_range_check()) { 360 if (TraceTraps) { 361 tty->print_cr("trap: range_check at " INTPTR_FORMAT " (SIGTRAP)", p2i(pc)); 362 } 363 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL); 364 } 365#endif 366 else if (sig == SIGBUS) { 367 // BugId 4454115: A read from a MappedByteBuffer can fault here if the 368 // underlying file has been truncated. Do not crash the VM in such a case. 369 CodeBlob* cb = CodeCache::find_blob_unsafe(pc); 370 nmethod* nm = (cb != NULL && cb->is_nmethod()) ? (nmethod*)cb : NULL; 371 if (nm != NULL && nm->has_unsafe_access()) { 372 // We don't really need a stub here! Just set the pending exeption and 373 // continue at the next instruction after the faulting read. Returning 374 // garbage from this read is ok. 375 thread->set_pending_unsafe_access_error(); 376 os::Linux::ucontext_set_pc(uc, pc + 4); 377 return true; 378 } 379 } 380 } 381 382 else { // thread->thread_state() != _thread_in_Java 383 if (sig == SIGILL && VM_Version::is_determine_features_test_running()) { 384 // SIGILL must be caused by VM_Version::determine_features(). 385 *(int *)pc = 0; // patch instruction to 0 to indicate that it causes a SIGILL, 386 // flushing of icache is not necessary. 387 stub = pc + 4; // continue with next instruction. 388 } 389 else if (thread->thread_state() == _thread_in_vm && 390 sig == SIGBUS && thread->doing_unsafe_access()) { 391 // We don't really need a stub here! Just set the pending exeption and 392 // continue at the next instruction after the faulting read. Returning 393 // garbage from this read is ok. 394 thread->set_pending_unsafe_access_error(); 395 os::Linux::ucontext_set_pc(uc, pc + 4); 396 return true; 397 } 398 } 399 400 // Check to see if we caught the safepoint code in the 401 // process of write protecting the memory serialization page. 402 // It write enables the page immediately after protecting it 403 // so we can just return to retry the write. 404 if ((sig == SIGSEGV) && 405 // Si_addr may not be valid due to a bug in the linux-ppc64 kernel (see comment above). 406 // Use is_memory_serialization instead of si_addr. 407 ((NativeInstruction*)pc)->is_memory_serialization(thread, ucVoid)) { 408 // Synchronization problem in the pseudo memory barrier code (bug id 6546278) 409 // Block current thread until the memory serialize page permission restored. 410 os::block_on_serialize_page_trap(); 411 return true; 412 } 413 } 414 415 if (stub != NULL) { 416 // Save all thread context in case we need to restore it. 417 if (thread != NULL) thread->set_saved_exception_pc(pc); 418 os::Linux::ucontext_set_pc(uc, stub); 419 return true; 420 } 421 422 // signal-chaining 423 if (os::Linux::chained_handler(sig, info, ucVoid)) { 424 return true; 425 } 426 427 if (!abort_if_unrecognized) { 428 // caller wants another chance, so give it to him 429 return false; 430 } 431 432 if (pc == NULL && uc != NULL) { 433 pc = os::Linux::ucontext_get_pc(uc); 434 } 435 436report_and_die: 437 // unmask current signal 438 sigset_t newset; 439 sigemptyset(&newset); 440 sigaddset(&newset, sig); 441 sigprocmask(SIG_UNBLOCK, &newset, NULL); 442 443 VMError::report_and_die(t, sig, pc, info, ucVoid); 444 445 ShouldNotReachHere(); 446 return false; 447} 448 449void os::Linux::init_thread_fpu_state(void) { 450 // Disable FP exceptions. 451 __asm__ __volatile__ ("mtfsfi 6,0"); 452} 453 454int os::Linux::get_fpu_control_word(void) { 455 // x86 has problems with FPU precision after pthread_cond_timedwait(). 456 // nothing to do on ppc64. 457 return 0; 458} 459 460void os::Linux::set_fpu_control_word(int fpu_control) { 461 // x86 has problems with FPU precision after pthread_cond_timedwait(). 462 // nothing to do on ppc64. 463} 464 465//////////////////////////////////////////////////////////////////////////////// 466// thread stack 467 468size_t os::Linux::min_stack_allowed = 128*K; 469 470// return default stack size for thr_type 471size_t os::Linux::default_stack_size(os::ThreadType thr_type) { 472 // default stack size (compiler thread needs larger stack) 473 // Notice that the setting for compiler threads here have no impact 474 // because of the strange 'fallback logic' in os::create_thread(). 475 // Better set CompilerThreadStackSize in globals_<os_cpu>.hpp if you want to 476 // specify a different stack size for compiler threads! 477 size_t s = (thr_type == os::compiler_thread ? 4 * M : 1024 * K); 478 return s; 479} 480 481size_t os::Linux::default_guard_size(os::ThreadType thr_type) { 482 return 2 * page_size(); 483} 484 485// Java thread: 486// 487// Low memory addresses 488// +------------------------+ 489// | |\ JavaThread created by VM does not have glibc 490// | glibc guard page | - guard, attached Java thread usually has 491// | |/ 1 page glibc guard. 492// P1 +------------------------+ Thread::stack_base() - Thread::stack_size() 493// | |\ 494// | HotSpot Guard Pages | - red and yellow pages 495// | |/ 496// +------------------------+ JavaThread::stack_yellow_zone_base() 497// | |\ 498// | Normal Stack | - 499// | |/ 500// P2 +------------------------+ Thread::stack_base() 501// 502// Non-Java thread: 503// 504// Low memory addresses 505// +------------------------+ 506// | |\ 507// | glibc guard page | - usually 1 page 508// | |/ 509// P1 +------------------------+ Thread::stack_base() - Thread::stack_size() 510// | |\ 511// | Normal Stack | - 512// | |/ 513// P2 +------------------------+ Thread::stack_base() 514// 515// ** P1 (aka bottom) and size ( P2 = P1 - size) are the address and stack size returned from 516// pthread_attr_getstack() 517 518static void current_stack_region(address * bottom, size_t * size) { 519 if (os::Linux::is_initial_thread()) { 520 // initial thread needs special handling because pthread_getattr_np() 521 // may return bogus value. 522 *bottom = os::Linux::initial_thread_stack_bottom(); 523 *size = os::Linux::initial_thread_stack_size(); 524 } else { 525 pthread_attr_t attr; 526 527 int rslt = pthread_getattr_np(pthread_self(), &attr); 528 529 // JVM needs to know exact stack location, abort if it fails 530 if (rslt != 0) { 531 if (rslt == ENOMEM) { 532 vm_exit_out_of_memory(0, OOM_MMAP_ERROR, "pthread_getattr_np"); 533 } else { 534 fatal("pthread_getattr_np failed with errno = %d", rslt); 535 } 536 } 537 538 if (pthread_attr_getstack(&attr, (void **)bottom, size) != 0) { 539 fatal("Can not locate current stack attributes!"); 540 } 541 542 pthread_attr_destroy(&attr); 543 544 } 545 assert(os::current_stack_pointer() >= *bottom && 546 os::current_stack_pointer() < *bottom + *size, "just checking"); 547} 548 549address os::current_stack_base() { 550 address bottom; 551 size_t size; 552 current_stack_region(&bottom, &size); 553 return (bottom + size); 554} 555 556size_t os::current_stack_size() { 557 // stack size includes normal stack and HotSpot guard pages 558 address bottom; 559 size_t size; 560 current_stack_region(&bottom, &size); 561 return size; 562} 563 564///////////////////////////////////////////////////////////////////////////// 565// helper functions for fatal error handler 566 567void os::print_context(outputStream *st, const void *context) { 568 if (context == NULL) return; 569 570 const ucontext_t* uc = (const ucontext_t*)context; 571 572 st->print_cr("Registers:"); 573 st->print("pc =" INTPTR_FORMAT " ", uc->uc_mcontext.regs->nip); 574 st->print("lr =" INTPTR_FORMAT " ", uc->uc_mcontext.regs->link); 575 st->print("ctr=" INTPTR_FORMAT " ", uc->uc_mcontext.regs->ctr); 576 st->cr(); 577 for (int i = 0; i < 32; i++) { 578 st->print("r%-2d=" INTPTR_FORMAT " ", i, uc->uc_mcontext.regs->gpr[i]); 579 if (i % 3 == 2) st->cr(); 580 } 581 st->cr(); 582 st->cr(); 583 584 intptr_t *sp = (intptr_t *)os::Linux::ucontext_get_sp(uc); 585 st->print_cr("Top of Stack: (sp=" PTR_FORMAT ")", p2i(sp)); 586 print_hex_dump(st, (address)sp, (address)(sp + 128), sizeof(intptr_t)); 587 st->cr(); 588 589 // Note: it may be unsafe to inspect memory near pc. For example, pc may 590 // point to garbage if entry point in an nmethod is corrupted. Leave 591 // this at the end, and hope for the best. 592 address pc = os::Linux::ucontext_get_pc(uc); 593 st->print_cr("Instructions: (pc=" PTR_FORMAT ")", p2i(pc)); 594 print_hex_dump(st, pc - 64, pc + 64, /*instrsize=*/4); 595 st->cr(); 596} 597 598void os::print_register_info(outputStream *st, const void *context) { 599 if (context == NULL) return; 600 601 const ucontext_t *uc = (const ucontext_t*)context; 602 603 st->print_cr("Register to memory mapping:"); 604 st->cr(); 605 606 // this is only for the "general purpose" registers 607 for (int i = 0; i < 32; i++) { 608 st->print("r%-2d=", i); 609 print_location(st, uc->uc_mcontext.regs->gpr[i]); 610 } 611 st->cr(); 612} 613 614extern "C" { 615 int SpinPause() { 616 return 0; 617 } 618} 619 620#ifndef PRODUCT 621void os::verify_stack_alignment() { 622 assert(((intptr_t)os::current_stack_pointer() & (StackAlignmentInBytes-1)) == 0, "incorrect stack alignment"); 623} 624#endif 625 626int os::extra_bang_size_in_bytes() { 627 // PPC does not require the additional stack bang. 628 return 0; 629} 630