rev 12696 : 8176872: [s390] wrong pc shown in error logs
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   1 /*
   2  * Copyright (c) 2016, Oracle and/or its affiliates. All rights reserved.
   3  * Copyright (c) 2016 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 // This file is organized as os_linux_x86.cpp.
  27 
  28 // no precompiled headers
  29 #include "asm/assembler.inline.hpp"
  30 #include "classfile/classLoader.hpp"
  31 #include "classfile/systemDictionary.hpp"
  32 #include "classfile/vmSymbols.hpp"
  33 #include "code/icBuffer.hpp"
  34 #include "code/nativeInst.hpp"
  35 #include "code/vtableStubs.hpp"
  36 #include "compiler/disassembler.hpp"
  37 #include "interpreter/interpreter.hpp"
  38 #include "jvm_linux.h"
  39 #include "memory/allocation.inline.hpp"
  40 #include "nativeInst_s390.hpp"
  41 #include "os_share_linux.hpp"
  42 #include "prims/jniFastGetField.hpp"
  43 #include "prims/jvm.h"
  44 #include "prims/jvm_misc.hpp"
  45 #include "runtime/arguments.hpp"
  46 #include "runtime/extendedPC.hpp"
  47 #include "runtime/frame.inline.hpp"
  48 #include "runtime/interfaceSupport.hpp"
  49 #include "runtime/java.hpp"
  50 #include "runtime/javaCalls.hpp"
  51 #include "runtime/mutexLocker.hpp"
  52 #include "runtime/osThread.hpp"
  53 #include "runtime/sharedRuntime.hpp"
  54 #include "runtime/stubRoutines.hpp"
  55 #include "runtime/thread.inline.hpp"
  56 #include "runtime/timer.hpp"
  57 #include "utilities/events.hpp"
  58 #include "utilities/vmError.hpp"
  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 
  81 address os::current_stack_pointer() {
  82   intptr_t* csp;
  83 
  84   // Inline assembly for `z_lgr regno(csp), Z_SP' (Z_SP = Z_R15):
  85   __asm__ __volatile__ ("lgr %0, 15":"=r"(csp):);
  86 
  87   assert(((uint64_t)csp & (frame::alignment_in_bytes-1)) == 0, "SP must be aligned");
  88   return (address) csp;
  89 }
  90 
  91 char* os::non_memory_address_word() {
  92   // Must never look like an address returned by reserve_memory,
  93   // even in its subfields (as defined by the CPU immediate fields,
  94   // if the CPU splits constants across multiple instructions).
  95   return (char*) -1;
  96 }
  97 
  98 // OS specific thread initialization.
  99 void os::initialize_thread(Thread* thread) { }
 100 
 101 // Frame information (pc, sp, fp) retrieved via ucontext
 102 // always looks like a C-frame according to the frame
 103 // conventions in frame_s390.hpp.
 104 address os::Linux::ucontext_get_pc(const ucontext_t * uc) {
 105   return (address)uc->uc_mcontext.psw.addr;
 106 }
 107 
 108 void os::Linux::ucontext_set_pc(ucontext_t * uc, address pc) {
 109   uc->uc_mcontext.psw.addr = (unsigned long)pc;
 110 }
 111 
 112 intptr_t* os::Linux::ucontext_get_sp(const ucontext_t * uc) {
 113   return (intptr_t*)uc->uc_mcontext.gregs[15/*REG_SP*/];
 114 }
 115 
 116 intptr_t* os::Linux::ucontext_get_fp(const ucontext_t * uc) {
 117   return NULL;
 118 }
 119 
 120 ExtendedPC os::fetch_frame_from_context(const void* ucVoid,
 121                     intptr_t** ret_sp, intptr_t** ret_fp) {
 122 
 123   ExtendedPC  epc;
 124   const ucontext_t* uc = (const ucontext_t*)ucVoid;
 125 
 126   if (uc != NULL) {
 127     epc = ExtendedPC(os::Linux::ucontext_get_pc(uc));
 128     if (ret_sp) { *ret_sp = os::Linux::ucontext_get_sp(uc); }
 129     if (ret_fp) { *ret_fp = os::Linux::ucontext_get_fp(uc); }
 130   } else {
 131     // Construct empty ExtendedPC for return value checking.
 132     epc = ExtendedPC(NULL);
 133     if (ret_sp) { *ret_sp = (intptr_t *)NULL; }
 134     if (ret_fp) { *ret_fp = (intptr_t *)NULL; }
 135   }
 136 
 137   return epc;
 138 }
 139 
 140 frame os::fetch_frame_from_context(const void* ucVoid) {
 141   intptr_t* sp;
 142   intptr_t* fp;
 143   ExtendedPC epc = fetch_frame_from_context(ucVoid, &sp, &fp);
 144   return frame(sp, epc.pc());
 145 }
 146 
 147 bool os::Linux::get_frame_at_stack_banging_point(JavaThread* thread, ucontext_t* uc, frame* fr) {
 148   address pc = (address) os::Linux::ucontext_get_pc(uc);
 149   if (Interpreter::contains(pc)) {
 150     // Interpreter performs stack banging after the fixed frame header has
 151     // been generated while the compilers perform it before. To maintain
 152     // semantic consistency between interpreted and compiled frames, the
 153     // method returns the Java sender of the current frame.
 154     *fr = os::fetch_frame_from_context(uc);
 155     if (!fr->is_first_java_frame()) {
 156       assert(fr->safe_for_sender(thread), "Safety check");
 157       *fr = fr->java_sender();
 158     }
 159   } else {
 160     // More complex code with compiled code.
 161     assert(!Interpreter::contains(pc), "Interpreted methods should have been handled above");
 162     CodeBlob* cb = CodeCache::find_blob(pc);
 163     if (cb == NULL || !cb->is_nmethod() || cb->is_frame_complete_at(pc)) {
 164       // Not sure where the pc points to, fallback to default
 165       // stack overflow handling. In compiled code, we bang before
 166       // the frame is complete.
 167       return false;
 168     } else {
 169       intptr_t* fp = os::Linux::ucontext_get_fp(uc);
 170       intptr_t* sp = os::Linux::ucontext_get_sp(uc);
 171       *fr = frame(sp, (address)*sp);
 172       if (!fr->is_java_frame()) {
 173         assert(fr->safe_for_sender(thread), "Safety check");
 174         assert(!fr->is_first_frame(), "Safety check");
 175         *fr = fr->java_sender();
 176       }
 177     }
 178   }
 179   assert(fr->is_java_frame(), "Safety check");
 180   return true;
 181 }
 182 
 183 frame os::get_sender_for_C_frame(frame* fr) {
 184   if (*fr->sp() == 0) {
 185     // fr is the last C frame.
 186     return frame();
 187   }
 188 
 189   // If its not one of our frames, the return pc is saved at gpr14
 190   // stack slot. The call_stub stores the return_pc to the stack slot
 191   // of gpr10.
 192   if ((Interpreter::code() != NULL && Interpreter::contains(fr->pc())) ||
 193       (CodeCache::contains(fr->pc()) && !StubRoutines::contains(fr->pc()))) {
 194     return frame(fr->sender_sp(), fr->sender_pc());
 195   } else {
 196     if (StubRoutines::contains(fr->pc())) {
 197       StubCodeDesc* desc = StubCodeDesc::desc_for(fr->pc());
 198       if (desc && !strcmp(desc->name(),"call_stub")) {
 199         return frame(fr->sender_sp(), fr->callstub_sender_pc());
 200       } else {
 201         return frame(fr->sender_sp(), fr->sender_pc());
 202       }
 203     } else {
 204       return frame(fr->sender_sp(), fr->native_sender_pc());
 205     }
 206   }
 207 }
 208 
 209 frame os::current_frame() {
 210   // Expected to return the stack pointer of this method.
 211   // But if inlined, returns the stack pointer of our caller!
 212   intptr_t* csp = (intptr_t*) *((intptr_t*) os::current_stack_pointer());
 213   assert (csp != NULL, "sp should not be NULL");
 214   // Pass a dummy pc. This way we don't have to load it from the
 215   // stack, since we don't know in which slot we can find it.
 216   frame topframe(csp, (address)0x8);
 217   if (os::is_first_C_frame(&topframe)) {
 218     // Stack is not walkable.
 219     return frame();
 220   } else {
 221     frame senderFrame = os::get_sender_for_C_frame(&topframe);
 222     assert(senderFrame.pc() != NULL, "Sender pc should not be NULL");
 223     // Return sender of sender of current topframe which hopefully
 224     // both have pc != NULL.
 225 #ifdef _NMT_NOINLINE_   // Is set in slowdebug builds.
 226     // Current_stack_pointer is not inlined, we must pop one more frame.
 227     frame tmp = os::get_sender_for_C_frame(&topframe);
 228     return os::get_sender_for_C_frame(&tmp);
 229 #else
 230     return os::get_sender_for_C_frame(&topframe);
 231 #endif
 232   }
 233 }
 234 
 235 // Utility functions
 236 
 237 extern "C" JNIEXPORT int
 238 JVM_handle_linux_signal(int sig,
 239                         siginfo_t* info,
 240                         void* ucVoid,
 241                         int abort_if_unrecognized) {
 242   ucontext_t* uc = (ucontext_t*) ucVoid;
 243 
 244   Thread* t = Thread::current_or_null_safe();
 245 
 246   // Must do this before SignalHandlerMark, if crash protection installed we will longjmp away
 247   // (no destructors can be run).
 248   os::WatcherThreadCrashProtection::check_crash_protection(sig, t);
 249 
 250   SignalHandlerMark shm(t);
 251 
 252   // Note: it's not uncommon that JNI code uses signal/sigset to install
 253   // then restore certain signal handler (e.g. to temporarily block SIGPIPE,
 254   // or have a SIGILL handler when detecting CPU type). When that happens,
 255   // JVM_handle_linux_signal() might be invoked with junk info/ucVoid. To
 256   // avoid unnecessary crash when libjsig is not preloaded, try handle signals
 257   // that do not require siginfo/ucontext first.
 258 
 259   if (sig == SIGPIPE) {
 260     if (os::Linux::chained_handler(sig, info, ucVoid)) {
 261       return true;
 262     } else {
 263       if (PrintMiscellaneous && (WizardMode || Verbose)) {
 264         warning("Ignoring SIGPIPE - see bug 4229104");
 265       }
 266       return true;
 267     }
 268   }
 269 
 270   JavaThread* thread = NULL;
 271   VMThread* vmthread = NULL;
 272   if (os::Linux::signal_handlers_are_installed) {
 273     if (t != NULL) {
 274       if(t->is_Java_thread()) {
 275         thread = (JavaThread*)t;
 276       } else if(t->is_VM_thread()) {
 277         vmthread = (VMThread *)t;
 278       }
 279     }
 280   }
 281 
 282   // Moved SafeFetch32 handling outside thread!=NULL conditional block to make
 283   // it work if no associated JavaThread object exists.
 284   if (uc) {
 285     address const pc = os::Linux::ucontext_get_pc(uc);
 286     if (pc && StubRoutines::is_safefetch_fault(pc)) {
 287       os::Linux::ucontext_set_pc(uc, StubRoutines::continuation_for_safefetch_fault(pc));
 288       return true;
 289     }
 290   }
 291 
 292   // Decide if this trap can be handled by a stub.
 293   address stub    = NULL;
 294   address pc      = NULL;  // Pc as retrieved from PSW. Usually points past failing instruction.
 295   address trap_pc = NULL;  // Pc of the instruction causing the trap.
 296 
 297   //%note os_trap_1
 298   if (info != NULL && uc != NULL && thread != NULL) {
 299     pc = os::Linux::ucontext_get_pc(uc);
 300     if (TraceTraps) {
 301       tty->print_cr("     pc at " INTPTR_FORMAT, p2i(pc));
 302     }
 303     if ((unsigned long)(pc - (address)info->si_addr) <= (unsigned long)Assembler::instr_maxlen() ) {
 304       trap_pc = (address)info->si_addr;
 305       if (TraceTraps) {
 306         tty->print_cr("trap_pc at " INTPTR_FORMAT, p2i(trap_pc));
 307       }
 308     }
 309 
 310     // Handle ALL stack overflow variations here
 311     if (sig == SIGSEGV) {
 312       address addr = (address)info->si_addr; // Address causing SIGSEGV, usually mem ref target.
 313 
 314       // Check if fault address is within thread stack.
 315       if (thread->on_local_stack(addr)) {
 316         // stack overflow
 317         if (thread->in_stack_yellow_reserved_zone(addr)) {
 318           if (thread->thread_state() == _thread_in_Java) {
 319             if (thread->in_stack_reserved_zone(addr)) {
 320               frame fr;
 321               if (os::Linux::get_frame_at_stack_banging_point(thread, uc, &fr)) {
 322                 assert(fr.is_java_frame(), "Must be a Javac frame");
 323                 frame activation =
 324                   SharedRuntime::look_for_reserved_stack_annotated_method(thread, fr);
 325                 if (activation.sp() != NULL) {
 326                   thread->disable_stack_reserved_zone();
 327                   if (activation.is_interpreted_frame()) {
 328                     thread->set_reserved_stack_activation((address)activation.fp());
 329                   } else {
 330                     thread->set_reserved_stack_activation((address)activation.unextended_sp());
 331                   }
 332                   return 1;
 333                 }
 334               }
 335             }
 336             // Throw a stack overflow exception.
 337             // Guard pages will be reenabled while unwinding the stack.
 338             thread->disable_stack_yellow_reserved_zone();
 339             stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::STACK_OVERFLOW);
 340           } else {
 341             // Thread was in the vm or native code. Return and try to finish.
 342             thread->disable_stack_yellow_reserved_zone();
 343             return 1;
 344           }
 345         } else if (thread->in_stack_red_zone(addr)) {
 346           // Fatal red zone violation.  Disable the guard pages and fall through
 347           // to handle_unexpected_exception way down below.
 348           thread->disable_stack_red_zone();
 349           tty->print_raw_cr("An irrecoverable stack overflow has occurred.");
 350 
 351           // This is a likely cause, but hard to verify. Let's just print
 352           // it as a hint.
 353           tty->print_raw_cr("Please check if any of your loaded .so files has "
 354                             "enabled executable stack (see man page execstack(8))");
 355         } else {
 356           // Accessing stack address below sp may cause SEGV if current
 357           // thread has MAP_GROWSDOWN stack. This should only happen when
 358           // current thread was created by user code with MAP_GROWSDOWN flag
 359           // and then attached to VM. See notes in os_linux.cpp.
 360           if (thread->osthread()->expanding_stack() == 0) {
 361              thread->osthread()->set_expanding_stack();
 362              if (os::Linux::manually_expand_stack(thread, addr)) {
 363                thread->osthread()->clear_expanding_stack();
 364                return 1;
 365              }
 366              thread->osthread()->clear_expanding_stack();
 367           } else {
 368              fatal("recursive segv. expanding stack.");
 369           }
 370         }
 371       }
 372     }
 373 
 374     if (thread->thread_state() == _thread_in_Java) {
 375       // Java thread running in Java code => find exception handler if any
 376       // a fault inside compiled code, the interpreter, or a stub
 377 
 378       // Handle signal from NativeJump::patch_verified_entry().
 379       if (sig == SIGILL && nativeInstruction_at(pc)->is_sigill_zombie_not_entrant()) {
 380         if (TraceTraps) {
 381           tty->print_cr("trap: zombie_not_entrant (SIGILL)");
 382         }
 383         stub = SharedRuntime::get_handle_wrong_method_stub();
 384       }
 385 
 386       else if (sig == SIGSEGV &&
 387                os::is_poll_address((address)info->si_addr)) {
 388         if (TraceTraps) {
 389           tty->print_cr("trap: safepoint_poll at " INTPTR_FORMAT " (SIGSEGV)", p2i(pc));
 390         }
 391         stub = SharedRuntime::get_poll_stub(pc);
 392 
 393         // Info->si_addr only points to the page base address, so we
 394         // must extract the real si_addr from the instruction and the
 395         // ucontext.
 396         assert(((NativeInstruction*)pc)->is_safepoint_poll(), "must be safepoint poll");
 397         const address real_si_addr = ((NativeInstruction*)pc)->get_poll_address(uc);
 398       }
 399 
 400       // SIGTRAP-based implicit null check in compiled code.
 401       else if ((sig == SIGFPE) &&
 402                TrapBasedNullChecks &&
 403                (trap_pc != NULL) &&
 404                Assembler::is_sigtrap_zero_check(trap_pc)) {
 405         if (TraceTraps) {
 406           tty->print_cr("trap: NULL_CHECK at " INTPTR_FORMAT " (SIGFPE)", p2i(trap_pc));
 407         }
 408         stub = SharedRuntime::continuation_for_implicit_exception(thread, trap_pc, SharedRuntime::IMPLICIT_NULL);
 409       }
 410 
 411       else if (sig == SIGSEGV && ImplicitNullChecks &&
 412                CodeCache::contains((void*) pc) &&
 413                !MacroAssembler::needs_explicit_null_check((intptr_t) info->si_addr)) {
 414         if (TraceTraps) {
 415           tty->print_cr("trap: null_check at " INTPTR_FORMAT " (SIGSEGV)", p2i(pc));
 416         }
 417         stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL);
 418       }
 419 
 420       // SIGTRAP-based implicit range check in compiled code.
 421       else if (sig == SIGFPE && TrapBasedRangeChecks &&
 422                (trap_pc != NULL) &&
 423                Assembler::is_sigtrap_range_check(trap_pc)) {
 424         if (TraceTraps) {
 425           tty->print_cr("trap: RANGE_CHECK at " INTPTR_FORMAT " (SIGFPE)", p2i(trap_pc));
 426         }
 427         stub = SharedRuntime::continuation_for_implicit_exception(thread, trap_pc, SharedRuntime::IMPLICIT_NULL);
 428       }
 429 
 430       else if (sig == SIGFPE && info->si_code == FPE_INTDIV) {
 431         stub = SharedRuntime::continuation_for_implicit_exception(thread, trap_pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO);
 432       }
 433 
 434       else if (sig == SIGBUS) {
 435         // BugId 4454115: A read from a MappedByteBuffer can fault here if the
 436         // underlying file has been truncated. Do not crash the VM in such a case.
 437         CodeBlob* cb = CodeCache::find_blob_unsafe(pc);
 438         CompiledMethod* nm = (cb != NULL) ? cb->as_compiled_method_or_null() : NULL;
 439         if (nm != NULL && nm->has_unsafe_access()) {
 440           // We don't really need a stub here! Just set the pending exeption and
 441           // continue at the next instruction after the faulting read. Returning
 442           // garbage from this read is ok.
 443           thread->set_pending_unsafe_access_error();
 444           uc->uc_mcontext.psw.addr = ((unsigned long)pc) + Assembler::instr_len(pc);
 445           return true;
 446         }
 447       }
 448     }
 449 
 450     else { // thread->thread_state() != _thread_in_Java
 451       if (sig == SIGILL && VM_Version::is_determine_features_test_running()) {
 452         // SIGILL must be caused by VM_Version::determine_features().
 453         //*(int *) (pc-6)=0; // Patch instruction to 0 to indicate that it causes a SIGILL.
 454                              // Flushing of icache is not necessary.
 455         stub = pc; // Continue with next instruction.
 456       } else if (thread->thread_state() == _thread_in_vm &&
 457                  sig == SIGBUS && thread->doing_unsafe_access()) {
 458         // We don't really need a stub here! Just set the pending exeption and
 459         // continue at the next instruction after the faulting read. Returning
 460         // garbage from this read is ok.
 461         thread->set_pending_unsafe_access_error();
 462         os::Linux::ucontext_set_pc(uc, pc + Assembler::instr_len(pc));
 463         return true;
 464       }
 465     }
 466 
 467     // Check to see if we caught the safepoint code in the
 468     // process of write protecting the memory serialization page.
 469     // It write enables the page immediately after protecting it
 470     // so we can just return to retry the write.
 471     // Info->si_addr need not be the exact address, it is only
 472     // guaranteed to be on the same page as the address that caused
 473     // the SIGSEGV.
 474     if ((sig == SIGSEGV) &&
 475         (os::get_memory_serialize_page() ==
 476          (address)((uintptr_t)info->si_addr & ~(os::vm_page_size()-1)))) {
 477       return true;
 478     }
 479   }
 480 
 481   if (stub != NULL) {
 482     // Save all thread context in case we need to restore it.
 483     if (thread != NULL) thread->set_saved_exception_pc(pc);
 484     os::Linux::ucontext_set_pc(uc, stub);
 485     return true;
 486   }
 487 
 488   // signal-chaining
 489   if (os::Linux::chained_handler(sig, info, ucVoid)) {
 490     return true;
 491   }
 492 
 493   if (!abort_if_unrecognized) {
 494     // caller wants another chance, so give it to him
 495     return false;
 496   }
 497 
 498   if (pc == NULL && uc != NULL) {
 499     pc = os::Linux::ucontext_get_pc(uc);
 500   }
 501 
 502   // unmask current signal
 503   sigset_t newset;
 504   sigemptyset(&newset);
 505   sigaddset(&newset, sig);
 506   sigprocmask(SIG_UNBLOCK, &newset, NULL);
 507 








 508   VMError::report_and_die(t, sig, pc, info, ucVoid);
 509 
 510   ShouldNotReachHere();
 511   return false;
 512 }
 513 
 514 void os::Linux::init_thread_fpu_state(void) {
 515   // Nothing to do on z/Architecture.
 516 }
 517 
 518 int os::Linux::get_fpu_control_word(void) {
 519   // Nothing to do on z/Architecture.
 520   return 0;
 521 }
 522 
 523 void os::Linux::set_fpu_control_word(int fpu_control) {
 524   // Nothing to do on z/Architecture.
 525 }
 526 
 527 ////////////////////////////////////////////////////////////////////////////////
 528 // thread stack
 529 
 530 // Minimum usable stack sizes required to get to user code. Space for
 531 // HotSpot guard pages is added later.
 532 size_t os::Posix::_compiler_thread_min_stack_allowed = (52 DEBUG_ONLY(+ 32)) * K;
 533 size_t os::Posix::_java_thread_min_stack_allowed = (32 DEBUG_ONLY(+ 8)) * K;
 534 size_t os::Posix::_vm_internal_thread_min_stack_allowed = 32 * K;
 535 
 536 // Return default stack size for thr_type.
 537 size_t os::Posix::default_stack_size(os::ThreadType thr_type) {
 538   // Default stack size (compiler thread needs larger stack).
 539   size_t s = (thr_type == os::compiler_thread ? 4 * M : 1024 * K);
 540   return s;
 541 }
 542 
 543 /////////////////////////////////////////////////////////////////////////////
 544 // helper functions for fatal error handler
 545 
 546 void os::print_context(outputStream *st, const void *context) {
 547   if (context == NULL) return;
 548 
 549   const ucontext_t* uc = (const ucontext_t*)context;
 550 
 551   st->print_cr("Processor state:");
 552   st->print_cr("----------------");
 553   st->print_cr("        ip = " INTPTR_FORMAT " ", uc->uc_mcontext.psw.addr);
 554   st->print_cr(" proc mask = " INTPTR_FORMAT " ", uc->uc_mcontext.psw.mask);
 555   st->print_cr("   fpc reg = 0x%8.8x "          , uc->uc_mcontext.fpregs.fpc);
 556   st->cr();
 557 
 558   st->print_cr("General Purpose Registers:");
 559   st->print_cr("--------------------------");
 560   for( int i = 0; i < 16; i+=2 ) {
 561     st->print("  r%-2d = " INTPTR_FORMAT "  " ,  i,   uc->uc_mcontext.gregs[i]);
 562     st->print("  r%-2d = " INTPTR_FORMAT "  |",  i+1, uc->uc_mcontext.gregs[i+1]);
 563     st->print("  r%-2d = %23.1ld  "           ,  i,   uc->uc_mcontext.gregs[i]);
 564     st->print("  r%-2d = %23.1ld  "           ,  i+1, uc->uc_mcontext.gregs[i+1]);
 565     st->cr();
 566   }
 567   st->cr();
 568 
 569   st->print_cr("Access Registers:");
 570   st->print_cr("-----------------");
 571   for( int i = 0; i < 16; i+=2 ) {
 572     st->print("  ar%-2d = 0x%8.8x  ", i,   uc->uc_mcontext.aregs[i]);
 573     st->print("  ar%-2d = 0x%8.8x  ", i+1, uc->uc_mcontext.aregs[i+1]);
 574     st->cr();
 575   }
 576   st->cr();
 577 
 578   st->print_cr("Float Registers:");
 579   st->print_cr("----------------");
 580   for (int i = 0; i < 16; i += 2) {
 581     st->print("  fr%-2d = " INTPTR_FORMAT "  " , i,   (int64_t)(uc->uc_mcontext.fpregs.fprs[i].d));
 582     st->print("  fr%-2d = " INTPTR_FORMAT "  |", i+1, (int64_t)(uc->uc_mcontext.fpregs.fprs[i+1].d));
 583     st->print("  fr%-2d = %23.15e  "           , i,   (uc->uc_mcontext.fpregs.fprs[i].d));
 584     st->print("  fr%-2d = %23.15e  "           , i+1, (uc->uc_mcontext.fpregs.fprs[i+1].d));
 585     st->cr();
 586   }
 587   st->cr();
 588   st->cr();
 589 
 590   intptr_t *sp = (intptr_t *)os::Linux::ucontext_get_sp(uc);
 591   st->print_cr("Top of Stack: (sp=" PTR_FORMAT ")", p2i(sp));
 592   print_hex_dump(st, (address)sp, (address)(sp + 128), sizeof(intptr_t));
 593   st->cr();
 594 
 595   // Note: it may be unsafe to inspect memory near pc. For example, pc may
 596   // point to garbage if entry point in an nmethod is corrupted. Leave
 597   // this at the end, and hope for the best.
 598   address pc = os::Linux::ucontext_get_pc(uc);
 599   if (Verbose) { st->print_cr("pc at " PTR_FORMAT, p2i(pc)); }
 600   st->print_cr("Instructions: (pc=" PTR_FORMAT ")", p2i(pc));
 601   print_hex_dump(st, pc-64, pc+64, /*intrsize=*/4);
 602   st->cr();
 603 }
 604 
 605 void os::print_register_info(outputStream *st, const void *context) {
 606   st->print("Not ported\n");
 607 }
 608 
 609 #ifndef PRODUCT
 610 void os::verify_stack_alignment() {
 611 }
 612 #endif
 613 
 614 int os::extra_bang_size_in_bytes() {
 615   // z/Architecture does not require the additional stack bang.
 616   return 0;
 617 }
--- EOF ---