1 /*
   2  * Copyright (c) 1999, 2016, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 // no precompiled headers
  26 #include "asm/macroAssembler.hpp"
  27 #include "classfile/classLoader.hpp"
  28 #include "classfile/systemDictionary.hpp"
  29 #include "classfile/vmSymbols.hpp"
  30 #include "code/codeCache.hpp"
  31 #include "code/icBuffer.hpp"
  32 #include "code/vtableStubs.hpp"
  33 #include "interpreter/interpreter.hpp"
  34 #include "jvm_bsd.h"
  35 #include "memory/allocation.inline.hpp"
  36 #include "os_share_bsd.hpp"
  37 #include "prims/jniFastGetField.hpp"
  38 #include "prims/jvm.h"
  39 #include "prims/jvm_misc.hpp"
  40 #include "runtime/arguments.hpp"
  41 #include "runtime/extendedPC.hpp"
  42 #include "runtime/frame.inline.hpp"
  43 #include "runtime/interfaceSupport.hpp"
  44 #include "runtime/java.hpp"
  45 #include "runtime/javaCalls.hpp"
  46 #include "runtime/mutexLocker.hpp"
  47 #include "runtime/osThread.hpp"
  48 #include "runtime/sharedRuntime.hpp"
  49 #include "runtime/stubRoutines.hpp"
  50 #include "runtime/thread.inline.hpp"
  51 #include "runtime/timer.hpp"
  52 #include "utilities/events.hpp"
  53 #include "utilities/vmError.hpp"
  54 
  55 // put OS-includes here
  56 # include <sys/types.h>
  57 # include <sys/mman.h>
  58 # include <pthread.h>
  59 # include <signal.h>
  60 # include <errno.h>
  61 # include <dlfcn.h>
  62 # include <stdlib.h>
  63 # include <stdio.h>
  64 # include <unistd.h>
  65 # include <sys/resource.h>
  66 # include <pthread.h>
  67 # include <sys/stat.h>
  68 # include <sys/time.h>
  69 # include <sys/utsname.h>
  70 # include <sys/socket.h>
  71 # include <sys/wait.h>
  72 # include <pwd.h>
  73 # include <poll.h>
  74 #ifndef __OpenBSD__
  75 # include <ucontext.h>
  76 #endif
  77 
  78 #if !defined(__APPLE__) && !defined(__NetBSD__)
  79 # include <pthread_np.h>
  80 #endif
  81 
  82 // needed by current_stack_region() workaround for Mavericks
  83 #if defined(__APPLE__)
  84 # include <errno.h>
  85 # include <sys/types.h>
  86 # include <sys/sysctl.h>
  87 # define DEFAULT_MAIN_THREAD_STACK_PAGES 2048
  88 # define OS_X_10_9_0_KERNEL_MAJOR_VERSION 13
  89 #endif
  90 
  91 #ifdef AMD64
  92 #define SPELL_REG_SP "rsp"
  93 #define SPELL_REG_FP "rbp"
  94 #else
  95 #define SPELL_REG_SP "esp"
  96 #define SPELL_REG_FP "ebp"
  97 #endif // AMD64
  98 
  99 #ifdef __FreeBSD__
 100 # define context_trapno uc_mcontext.mc_trapno
 101 # ifdef AMD64
 102 #  define context_pc uc_mcontext.mc_rip
 103 #  define context_sp uc_mcontext.mc_rsp
 104 #  define context_fp uc_mcontext.mc_rbp
 105 #  define context_rip uc_mcontext.mc_rip
 106 #  define context_rsp uc_mcontext.mc_rsp
 107 #  define context_rbp uc_mcontext.mc_rbp
 108 #  define context_rax uc_mcontext.mc_rax
 109 #  define context_rbx uc_mcontext.mc_rbx
 110 #  define context_rcx uc_mcontext.mc_rcx
 111 #  define context_rdx uc_mcontext.mc_rdx
 112 #  define context_rsi uc_mcontext.mc_rsi
 113 #  define context_rdi uc_mcontext.mc_rdi
 114 #  define context_r8  uc_mcontext.mc_r8
 115 #  define context_r9  uc_mcontext.mc_r9
 116 #  define context_r10 uc_mcontext.mc_r10
 117 #  define context_r11 uc_mcontext.mc_r11
 118 #  define context_r12 uc_mcontext.mc_r12
 119 #  define context_r13 uc_mcontext.mc_r13
 120 #  define context_r14 uc_mcontext.mc_r14
 121 #  define context_r15 uc_mcontext.mc_r15
 122 #  define context_flags uc_mcontext.mc_flags
 123 #  define context_err uc_mcontext.mc_err
 124 # else
 125 #  define context_pc uc_mcontext.mc_eip
 126 #  define context_sp uc_mcontext.mc_esp
 127 #  define context_fp uc_mcontext.mc_ebp
 128 #  define context_eip uc_mcontext.mc_eip
 129 #  define context_esp uc_mcontext.mc_esp
 130 #  define context_eax uc_mcontext.mc_eax
 131 #  define context_ebx uc_mcontext.mc_ebx
 132 #  define context_ecx uc_mcontext.mc_ecx
 133 #  define context_edx uc_mcontext.mc_edx
 134 #  define context_ebp uc_mcontext.mc_ebp
 135 #  define context_esi uc_mcontext.mc_esi
 136 #  define context_edi uc_mcontext.mc_edi
 137 #  define context_eflags uc_mcontext.mc_eflags
 138 #  define context_trapno uc_mcontext.mc_trapno
 139 # endif
 140 #endif
 141 
 142 #ifdef __APPLE__
 143 # if __DARWIN_UNIX03 && (MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5)
 144   // 10.5 UNIX03 member name prefixes
 145   #define DU3_PREFIX(s, m) __ ## s.__ ## m
 146 # else
 147   #define DU3_PREFIX(s, m) s ## . ## m
 148 # endif
 149 
 150 # ifdef AMD64
 151 #  define context_pc context_rip
 152 #  define context_sp context_rsp
 153 #  define context_fp context_rbp
 154 #  define context_rip uc_mcontext->DU3_PREFIX(ss,rip)
 155 #  define context_rsp uc_mcontext->DU3_PREFIX(ss,rsp)
 156 #  define context_rax uc_mcontext->DU3_PREFIX(ss,rax)
 157 #  define context_rbx uc_mcontext->DU3_PREFIX(ss,rbx)
 158 #  define context_rcx uc_mcontext->DU3_PREFIX(ss,rcx)
 159 #  define context_rdx uc_mcontext->DU3_PREFIX(ss,rdx)
 160 #  define context_rbp uc_mcontext->DU3_PREFIX(ss,rbp)
 161 #  define context_rsi uc_mcontext->DU3_PREFIX(ss,rsi)
 162 #  define context_rdi uc_mcontext->DU3_PREFIX(ss,rdi)
 163 #  define context_r8  uc_mcontext->DU3_PREFIX(ss,r8)
 164 #  define context_r9  uc_mcontext->DU3_PREFIX(ss,r9)
 165 #  define context_r10 uc_mcontext->DU3_PREFIX(ss,r10)
 166 #  define context_r11 uc_mcontext->DU3_PREFIX(ss,r11)
 167 #  define context_r12 uc_mcontext->DU3_PREFIX(ss,r12)
 168 #  define context_r13 uc_mcontext->DU3_PREFIX(ss,r13)
 169 #  define context_r14 uc_mcontext->DU3_PREFIX(ss,r14)
 170 #  define context_r15 uc_mcontext->DU3_PREFIX(ss,r15)
 171 #  define context_flags uc_mcontext->DU3_PREFIX(ss,rflags)
 172 #  define context_trapno uc_mcontext->DU3_PREFIX(es,trapno)
 173 #  define context_err uc_mcontext->DU3_PREFIX(es,err)
 174 # else
 175 #  define context_pc context_eip
 176 #  define context_sp context_esp
 177 #  define context_fp context_ebp
 178 #  define context_eip uc_mcontext->DU3_PREFIX(ss,eip)
 179 #  define context_esp uc_mcontext->DU3_PREFIX(ss,esp)
 180 #  define context_eax uc_mcontext->DU3_PREFIX(ss,eax)
 181 #  define context_ebx uc_mcontext->DU3_PREFIX(ss,ebx)
 182 #  define context_ecx uc_mcontext->DU3_PREFIX(ss,ecx)
 183 #  define context_edx uc_mcontext->DU3_PREFIX(ss,edx)
 184 #  define context_ebp uc_mcontext->DU3_PREFIX(ss,ebp)
 185 #  define context_esi uc_mcontext->DU3_PREFIX(ss,esi)
 186 #  define context_edi uc_mcontext->DU3_PREFIX(ss,edi)
 187 #  define context_eflags uc_mcontext->DU3_PREFIX(ss,eflags)
 188 #  define context_trapno uc_mcontext->DU3_PREFIX(es,trapno)
 189 # endif
 190 #endif
 191 
 192 #ifdef __OpenBSD__
 193 # define context_trapno sc_trapno
 194 # ifdef AMD64
 195 #  define context_pc sc_rip
 196 #  define context_sp sc_rsp
 197 #  define context_fp sc_rbp
 198 #  define context_rip sc_rip
 199 #  define context_rsp sc_rsp
 200 #  define context_rbp sc_rbp
 201 #  define context_rax sc_rax
 202 #  define context_rbx sc_rbx
 203 #  define context_rcx sc_rcx
 204 #  define context_rdx sc_rdx
 205 #  define context_rsi sc_rsi
 206 #  define context_rdi sc_rdi
 207 #  define context_r8  sc_r8
 208 #  define context_r9  sc_r9
 209 #  define context_r10 sc_r10
 210 #  define context_r11 sc_r11
 211 #  define context_r12 sc_r12
 212 #  define context_r13 sc_r13
 213 #  define context_r14 sc_r14
 214 #  define context_r15 sc_r15
 215 #  define context_flags sc_rflags
 216 #  define context_err sc_err
 217 # else
 218 #  define context_pc sc_eip
 219 #  define context_sp sc_esp
 220 #  define context_fp sc_ebp
 221 #  define context_eip sc_eip
 222 #  define context_esp sc_esp
 223 #  define context_eax sc_eax
 224 #  define context_ebx sc_ebx
 225 #  define context_ecx sc_ecx
 226 #  define context_edx sc_edx
 227 #  define context_ebp sc_ebp
 228 #  define context_esi sc_esi
 229 #  define context_edi sc_edi
 230 #  define context_eflags sc_eflags
 231 #  define context_trapno sc_trapno
 232 # endif
 233 #endif
 234 
 235 #ifdef __NetBSD__
 236 # define context_trapno uc_mcontext.__gregs[_REG_TRAPNO]
 237 # ifdef AMD64
 238 #  define __register_t __greg_t
 239 #  define context_pc uc_mcontext.__gregs[_REG_RIP]
 240 #  define context_sp uc_mcontext.__gregs[_REG_URSP]
 241 #  define context_fp uc_mcontext.__gregs[_REG_RBP]
 242 #  define context_rip uc_mcontext.__gregs[_REG_RIP]
 243 #  define context_rsp uc_mcontext.__gregs[_REG_URSP]
 244 #  define context_rax uc_mcontext.__gregs[_REG_RAX]
 245 #  define context_rbx uc_mcontext.__gregs[_REG_RBX]
 246 #  define context_rcx uc_mcontext.__gregs[_REG_RCX]
 247 #  define context_rdx uc_mcontext.__gregs[_REG_RDX]
 248 #  define context_rbp uc_mcontext.__gregs[_REG_RBP]
 249 #  define context_rsi uc_mcontext.__gregs[_REG_RSI]
 250 #  define context_rdi uc_mcontext.__gregs[_REG_RDI]
 251 #  define context_r8  uc_mcontext.__gregs[_REG_R8]
 252 #  define context_r9  uc_mcontext.__gregs[_REG_R9]
 253 #  define context_r10 uc_mcontext.__gregs[_REG_R10]
 254 #  define context_r11 uc_mcontext.__gregs[_REG_R11]
 255 #  define context_r12 uc_mcontext.__gregs[_REG_R12]
 256 #  define context_r13 uc_mcontext.__gregs[_REG_R13]
 257 #  define context_r14 uc_mcontext.__gregs[_REG_R14]
 258 #  define context_r15 uc_mcontext.__gregs[_REG_R15]
 259 #  define context_flags uc_mcontext.__gregs[_REG_RFL]
 260 #  define context_err uc_mcontext.__gregs[_REG_ERR]
 261 # else
 262 #  define context_pc uc_mcontext.__gregs[_REG_EIP]
 263 #  define context_sp uc_mcontext.__gregs[_REG_UESP]
 264 #  define context_fp uc_mcontext.__gregs[_REG_EBP]
 265 #  define context_eip uc_mcontext.__gregs[_REG_EIP]
 266 #  define context_esp uc_mcontext.__gregs[_REG_UESP]
 267 #  define context_eax uc_mcontext.__gregs[_REG_EAX]
 268 #  define context_ebx uc_mcontext.__gregs[_REG_EBX]
 269 #  define context_ecx uc_mcontext.__gregs[_REG_ECX]
 270 #  define context_edx uc_mcontext.__gregs[_REG_EDX]
 271 #  define context_ebp uc_mcontext.__gregs[_REG_EBP]
 272 #  define context_esi uc_mcontext.__gregs[_REG_ESI]
 273 #  define context_edi uc_mcontext.__gregs[_REG_EDI]
 274 #  define context_eflags uc_mcontext.__gregs[_REG_EFL]
 275 #  define context_trapno uc_mcontext.__gregs[_REG_TRAPNO]
 276 # endif
 277 #endif
 278 
 279 address os::current_stack_pointer() {
 280 #if defined(__clang__) || defined(__llvm__)
 281   register void *esp;
 282   __asm__("mov %%"SPELL_REG_SP", %0":"=r"(esp));
 283   return (address) esp;
 284 #elif defined(SPARC_WORKS)
 285   register void *esp;
 286   __asm__("mov %%"SPELL_REG_SP", %0":"=r"(esp));
 287   return (address) ((char*)esp + sizeof(long)*2);
 288 #else
 289   register void *esp __asm__ (SPELL_REG_SP);
 290   return (address) esp;
 291 #endif
 292 }
 293 
 294 char* os::non_memory_address_word() {
 295   // Must never look like an address returned by reserve_memory,
 296   // even in its subfields (as defined by the CPU immediate fields,
 297   // if the CPU splits constants across multiple instructions).
 298 
 299   return (char*) -1;
 300 }
 301 
 302 void os::initialize_thread(Thread* thr) {
 303 // Nothing to do.
 304 }
 305 
 306 address os::Bsd::ucontext_get_pc(const ucontext_t * uc) {
 307   return (address)uc->context_pc;
 308 }
 309 
 310 void os::Bsd::ucontext_set_pc(ucontext_t * uc, address pc) {
 311   uc->context_pc = (intptr_t)pc ;
 312 }
 313 
 314 intptr_t* os::Bsd::ucontext_get_sp(const ucontext_t * uc) {
 315   return (intptr_t*)uc->context_sp;
 316 }
 317 
 318 intptr_t* os::Bsd::ucontext_get_fp(const ucontext_t * uc) {
 319   return (intptr_t*)uc->context_fp;
 320 }
 321 
 322 // For Forte Analyzer AsyncGetCallTrace profiling support - thread
 323 // is currently interrupted by SIGPROF.
 324 // os::Solaris::fetch_frame_from_ucontext() tries to skip nested signal
 325 // frames. Currently we don't do that on Bsd, so it's the same as
 326 // os::fetch_frame_from_context().
 327 // This method is also used for stack overflow signal handling.
 328 ExtendedPC os::Bsd::fetch_frame_from_ucontext(Thread* thread,
 329   const ucontext_t* uc, intptr_t** ret_sp, intptr_t** ret_fp) {
 330 
 331   assert(thread != NULL, "just checking");
 332   assert(ret_sp != NULL, "just checking");
 333   assert(ret_fp != NULL, "just checking");
 334 
 335   return os::fetch_frame_from_context(uc, ret_sp, ret_fp);
 336 }
 337 
 338 ExtendedPC os::fetch_frame_from_context(const void* ucVoid,
 339                     intptr_t** ret_sp, intptr_t** ret_fp) {
 340 
 341   ExtendedPC  epc;
 342   const ucontext_t* uc = (const ucontext_t*)ucVoid;
 343 
 344   if (uc != NULL) {
 345     epc = ExtendedPC(os::Bsd::ucontext_get_pc(uc));
 346     if (ret_sp) *ret_sp = os::Bsd::ucontext_get_sp(uc);
 347     if (ret_fp) *ret_fp = os::Bsd::ucontext_get_fp(uc);
 348   } else {
 349     // construct empty ExtendedPC for return value checking
 350     epc = ExtendedPC(NULL);
 351     if (ret_sp) *ret_sp = (intptr_t *)NULL;
 352     if (ret_fp) *ret_fp = (intptr_t *)NULL;
 353   }
 354 
 355   return epc;
 356 }
 357 
 358 frame os::fetch_frame_from_context(const void* ucVoid) {
 359   intptr_t* sp;
 360   intptr_t* fp;
 361   ExtendedPC epc = fetch_frame_from_context(ucVoid, &sp, &fp);
 362   return frame(sp, fp, epc.pc());
 363 }
 364 
 365 frame os::fetch_frame_from_ucontext(Thread* thread, void* ucVoid) {
 366   intptr_t* sp;
 367   intptr_t* fp;
 368   ExtendedPC epc = os::Bsd::fetch_frame_from_ucontext(thread, (ucontext_t*)ucVoid, &sp, &fp);
 369   return frame(sp, fp, epc.pc());
 370 }
 371 
 372 bool os::Bsd::get_frame_at_stack_banging_point(JavaThread* thread, ucontext_t* uc, frame* fr) {
 373   address pc = (address) os::Bsd::ucontext_get_pc(uc);
 374   if (Interpreter::contains(pc)) {
 375     // interpreter performs stack banging after the fixed frame header has
 376     // been generated while the compilers perform it before. To maintain
 377     // semantic consistency between interpreted and compiled frames, the
 378     // method returns the Java sender of the current frame.
 379     *fr = os::fetch_frame_from_ucontext(thread, uc);
 380     if (!fr->is_first_java_frame()) {
 381       // get_frame_at_stack_banging_point() is only called when we
 382       // have well defined stacks so java_sender() calls do not need
 383       // to assert safe_for_sender() first.
 384       *fr = fr->java_sender();
 385     }
 386   } else {
 387     // more complex code with compiled code
 388     assert(!Interpreter::contains(pc), "Interpreted methods should have been handled above");
 389     CodeBlob* cb = CodeCache::find_blob(pc);
 390     if (cb == NULL || !cb->is_nmethod() || cb->is_frame_complete_at(pc)) {
 391       // Not sure where the pc points to, fallback to default
 392       // stack overflow handling
 393       return false;
 394     } else {
 395       *fr = os::fetch_frame_from_ucontext(thread, uc);
 396       // in compiled code, the stack banging is performed just after the return pc
 397       // has been pushed on the stack
 398       *fr = frame(fr->sp() + 1, fr->fp(), (address)*(fr->sp()));
 399       if (!fr->is_java_frame()) {
 400         // See java_sender() comment above.
 401         *fr = fr->java_sender();
 402       }
 403     }
 404   }
 405   assert(fr->is_java_frame(), "Safety check");
 406   return true;
 407 }
 408 
 409 // By default, gcc always save frame pointer (%ebp/%rbp) on stack. It may get
 410 // turned off by -fomit-frame-pointer,
 411 frame os::get_sender_for_C_frame(frame* fr) {
 412   return frame(fr->sender_sp(), fr->link(), fr->sender_pc());
 413 }
 414 
 415 intptr_t* _get_previous_fp() {
 416 #if defined(SPARC_WORKS) || defined(__clang__) || defined(__llvm__)
 417   register intptr_t **ebp;
 418   __asm__("mov %%"SPELL_REG_FP", %0":"=r"(ebp));
 419 #else
 420   register intptr_t **ebp __asm__ (SPELL_REG_FP);
 421 #endif
 422   // ebp is for this frame (_get_previous_fp). We want the ebp for the
 423   // caller of os::current_frame*(), so go up two frames. However, for
 424   // optimized builds, _get_previous_fp() will be inlined, so only go
 425   // up 1 frame in that case.
 426 #ifdef _NMT_NOINLINE_
 427   return **(intptr_t***)ebp;
 428 #else
 429   return *ebp;
 430 #endif
 431 }
 432 
 433 
 434 frame os::current_frame() {
 435   intptr_t* fp = _get_previous_fp();
 436   frame myframe((intptr_t*)os::current_stack_pointer(),
 437                 (intptr_t*)fp,
 438                 CAST_FROM_FN_PTR(address, os::current_frame));
 439   if (os::is_first_C_frame(&myframe)) {
 440     // stack is not walkable
 441     return frame();
 442   } else {
 443     return os::get_sender_for_C_frame(&myframe);
 444   }
 445 }
 446 
 447 // Utility functions
 448 
 449 // From IA32 System Programming Guide
 450 enum {
 451   trap_page_fault = 0xE
 452 };
 453 
 454 extern "C" JNIEXPORT int
 455 JVM_handle_bsd_signal(int sig,
 456                         siginfo_t* info,
 457                         void* ucVoid,
 458                         int abort_if_unrecognized) {
 459   ucontext_t* uc = (ucontext_t*) ucVoid;
 460 
 461   Thread* t = Thread::current_or_null_safe();
 462 
 463   // Must do this before SignalHandlerMark, if crash protection installed we will longjmp away
 464   // (no destructors can be run)
 465   os::WatcherThreadCrashProtection::check_crash_protection(sig, t);
 466 
 467   SignalHandlerMark shm(t);
 468 
 469   // Note: it's not uncommon that JNI code uses signal/sigset to install
 470   // then restore certain signal handler (e.g. to temporarily block SIGPIPE,
 471   // or have a SIGILL handler when detecting CPU type). When that happens,
 472   // JVM_handle_bsd_signal() might be invoked with junk info/ucVoid. To
 473   // avoid unnecessary crash when libjsig is not preloaded, try handle signals
 474   // that do not require siginfo/ucontext first.
 475 
 476   if (sig == SIGPIPE || sig == SIGXFSZ) {
 477     // allow chained handler to go first
 478     if (os::Bsd::chained_handler(sig, info, ucVoid)) {
 479       return true;
 480     } else {
 481       // Ignoring SIGPIPE/SIGXFSZ - see bugs 4229104 or 6499219
 482       return true;
 483     }
 484   }
 485 
 486   JavaThread* thread = NULL;
 487   VMThread* vmthread = NULL;
 488   if (os::Bsd::signal_handlers_are_installed) {
 489     if (t != NULL ){
 490       if(t->is_Java_thread()) {
 491         thread = (JavaThread*)t;
 492       }
 493       else if(t->is_VM_thread()){
 494         vmthread = (VMThread *)t;
 495       }
 496     }
 497   }
 498 /*
 499   NOTE: does not seem to work on bsd.
 500   if (info == NULL || info->si_code <= 0 || info->si_code == SI_NOINFO) {
 501     // can't decode this kind of signal
 502     info = NULL;
 503   } else {
 504     assert(sig == info->si_signo, "bad siginfo");
 505   }
 506 */
 507   // decide if this trap can be handled by a stub
 508   address stub = NULL;
 509 
 510   address pc          = NULL;
 511 
 512   //%note os_trap_1
 513   if (info != NULL && uc != NULL && thread != NULL) {
 514     pc = (address) os::Bsd::ucontext_get_pc(uc);
 515 
 516     if (StubRoutines::is_safefetch_fault(pc)) {
 517       os::Bsd::ucontext_set_pc(uc, StubRoutines::continuation_for_safefetch_fault(pc));
 518       return 1;
 519     }
 520 
 521     // Handle ALL stack overflow variations here
 522     if (sig == SIGSEGV || sig == SIGBUS) {
 523       address addr = (address) info->si_addr;
 524 
 525       // check if fault address is within thread stack
 526       if (thread->on_local_stack(addr)) {
 527         // stack overflow
 528         if (thread->in_stack_yellow_reserved_zone(addr)) {
 529           if (thread->thread_state() == _thread_in_Java) {
 530             if (thread->in_stack_reserved_zone(addr)) {
 531               frame fr;
 532               if (os::Bsd::get_frame_at_stack_banging_point(thread, uc, &fr)) {
 533                 assert(fr.is_java_frame(), "Must be a Java frame");
 534                 frame activation = SharedRuntime::look_for_reserved_stack_annotated_method(thread, fr);
 535                 if (activation.sp() != NULL) {
 536                   thread->disable_stack_reserved_zone();
 537                   if (activation.is_interpreted_frame()) {
 538                     thread->set_reserved_stack_activation((address)(
 539                       activation.fp() + frame::interpreter_frame_initial_sp_offset));
 540                   } else {
 541                     thread->set_reserved_stack_activation((address)activation.unextended_sp());
 542                   }
 543                   return 1;
 544                 }
 545               }
 546             }
 547             // Throw a stack overflow exception.  Guard pages will be reenabled
 548             // while unwinding the stack.
 549             thread->disable_stack_yellow_reserved_zone();
 550             stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::STACK_OVERFLOW);
 551           } else {
 552             // Thread was in the vm or native code.  Return and try to finish.
 553             thread->disable_stack_yellow_reserved_zone();
 554             return 1;
 555           }
 556         } else if (thread->in_stack_red_zone(addr)) {
 557           // Fatal red zone violation.  Disable the guard pages and fall through
 558           // to handle_unexpected_exception way down below.
 559           thread->disable_stack_red_zone();
 560           tty->print_raw_cr("An irrecoverable stack overflow has occurred.");
 561         }
 562       }
 563     }
 564 
 565     if ((sig == SIGSEGV || sig == SIGBUS) && VM_Version::is_cpuinfo_segv_addr(pc)) {
 566       // Verify that OS save/restore AVX registers.
 567       stub = VM_Version::cpuinfo_cont_addr();
 568     }
 569 
 570     // We test if stub is already set (by the stack overflow code
 571     // above) so it is not overwritten by the code that follows. This
 572     // check is not required on other platforms, because on other
 573     // platforms we check for SIGSEGV only or SIGBUS only, where here
 574     // we have to check for both SIGSEGV and SIGBUS.
 575     if (thread->thread_state() == _thread_in_Java && stub == NULL) {
 576       // Java thread running in Java code => find exception handler if any
 577       // a fault inside compiled code, the interpreter, or a stub
 578 
 579       if ((sig == SIGSEGV || sig == SIGBUS) && os::is_poll_address((address)info->si_addr)) {
 580         stub = SharedRuntime::get_poll_stub(pc);
 581 #if defined(__APPLE__)
 582       // 32-bit Darwin reports a SIGBUS for nearly all memory access exceptions.
 583       // 64-bit Darwin may also use a SIGBUS (seen with compressed oops).
 584       // Catching SIGBUS here prevents the implicit SIGBUS NULL check below from
 585       // being called, so only do so if the implicit NULL check is not necessary.
 586       } else if (sig == SIGBUS && MacroAssembler::needs_explicit_null_check((intptr_t)info->si_addr)) {
 587 #else
 588       } else if (sig == SIGBUS /* && info->si_code == BUS_OBJERR */) {
 589 #endif
 590         // BugId 4454115: A read from a MappedByteBuffer can fault
 591         // here if the underlying file has been truncated.
 592         // Do not crash the VM in such a case.
 593         CodeBlob* cb = CodeCache::find_blob_unsafe(pc);
 594         CompiledMethod* nm = (cb != NULL) ? cb->as_compiled_method_or_null() : NULL;
 595         if (nm != NULL && nm->has_unsafe_access()) {
 596           address next_pc = Assembler::locate_next_instruction(pc);
 597           stub = SharedRuntime::handle_unsafe_access(thread, next_pc);
 598         }
 599       }
 600       else
 601 
 602 #ifdef AMD64
 603       if (sig == SIGFPE  &&
 604           (info->si_code == FPE_INTDIV || info->si_code == FPE_FLTDIV)) {
 605         stub =
 606           SharedRuntime::
 607           continuation_for_implicit_exception(thread,
 608                                               pc,
 609                                               SharedRuntime::
 610                                               IMPLICIT_DIVIDE_BY_ZERO);
 611 #ifdef __APPLE__
 612       } else if (sig == SIGFPE && info->si_code == FPE_NOOP) {
 613         int op = pc[0];
 614 
 615         // Skip REX
 616         if ((pc[0] & 0xf0) == 0x40) {
 617           op = pc[1];
 618         } else {
 619           op = pc[0];
 620         }
 621 
 622         // Check for IDIV
 623         if (op == 0xF7) {
 624           stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime:: IMPLICIT_DIVIDE_BY_ZERO);
 625         } else {
 626           // TODO: handle more cases if we are using other x86 instructions
 627           //   that can generate SIGFPE signal.
 628           tty->print_cr("unknown opcode 0x%X with SIGFPE.", op);
 629           fatal("please update this code.");
 630         }
 631 #endif /* __APPLE__ */
 632 
 633 #else
 634       if (sig == SIGFPE /* && info->si_code == FPE_INTDIV */) {
 635         // HACK: si_code does not work on bsd 2.2.12-20!!!
 636         int op = pc[0];
 637         if (op == 0xDB) {
 638           // FIST
 639           // TODO: The encoding of D2I in i486.ad can cause an exception
 640           // prior to the fist instruction if there was an invalid operation
 641           // pending. We want to dismiss that exception. From the win_32
 642           // side it also seems that if it really was the fist causing
 643           // the exception that we do the d2i by hand with different
 644           // rounding. Seems kind of weird.
 645           // NOTE: that we take the exception at the NEXT floating point instruction.
 646           assert(pc[0] == 0xDB, "not a FIST opcode");
 647           assert(pc[1] == 0x14, "not a FIST opcode");
 648           assert(pc[2] == 0x24, "not a FIST opcode");
 649           return true;
 650         } else if (op == 0xF7) {
 651           // IDIV
 652           stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO);
 653         } else {
 654           // TODO: handle more cases if we are using other x86 instructions
 655           //   that can generate SIGFPE signal on bsd.
 656           tty->print_cr("unknown opcode 0x%X with SIGFPE.", op);
 657           fatal("please update this code.");
 658         }
 659 #endif // AMD64
 660       } else if ((sig == SIGSEGV || sig == SIGBUS) &&
 661                !MacroAssembler::needs_explicit_null_check((intptr_t)info->si_addr)) {
 662           // Determination of interpreter/vtable stub/compiled code null exception
 663           stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL);
 664       }
 665     } else if (thread->thread_state() == _thread_in_vm &&
 666                sig == SIGBUS && /* info->si_code == BUS_OBJERR && */
 667                thread->doing_unsafe_access()) {
 668         address next_pc = Assembler::locate_next_instruction(pc);
 669         stub = SharedRuntime::handle_unsafe_access(thread, next_pc);
 670     }
 671 
 672     // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC kicks in
 673     // and the heap gets shrunk before the field access.
 674     if ((sig == SIGSEGV) || (sig == SIGBUS)) {
 675       address addr = JNI_FastGetField::find_slowcase_pc(pc);
 676       if (addr != (address)-1) {
 677         stub = addr;
 678       }
 679     }
 680 
 681     // Check to see if we caught the safepoint code in the
 682     // process of write protecting the memory serialization page.
 683     // It write enables the page immediately after protecting it
 684     // so we can just return to retry the write.
 685     if ((sig == SIGSEGV || sig == SIGBUS) &&
 686         os::is_memory_serialize_page(thread, (address) info->si_addr)) {
 687       // Block current thread until the memory serialize page permission restored.
 688       os::block_on_serialize_page_trap();
 689       return true;
 690     }
 691   }
 692 
 693 #ifndef AMD64
 694   // Execution protection violation
 695   //
 696   // This should be kept as the last step in the triage.  We don't
 697   // have a dedicated trap number for a no-execute fault, so be
 698   // conservative and allow other handlers the first shot.
 699   //
 700   // Note: We don't test that info->si_code == SEGV_ACCERR here.
 701   // this si_code is so generic that it is almost meaningless; and
 702   // the si_code for this condition may change in the future.
 703   // Furthermore, a false-positive should be harmless.
 704   if (UnguardOnExecutionViolation > 0 &&
 705       (sig == SIGSEGV || sig == SIGBUS) &&
 706       uc->context_trapno == trap_page_fault) {
 707     int page_size = os::vm_page_size();
 708     address addr = (address) info->si_addr;
 709     address pc = os::Bsd::ucontext_get_pc(uc);
 710     // Make sure the pc and the faulting address are sane.
 711     //
 712     // If an instruction spans a page boundary, and the page containing
 713     // the beginning of the instruction is executable but the following
 714     // page is not, the pc and the faulting address might be slightly
 715     // different - we still want to unguard the 2nd page in this case.
 716     //
 717     // 15 bytes seems to be a (very) safe value for max instruction size.
 718     bool pc_is_near_addr =
 719       (pointer_delta((void*) addr, (void*) pc, sizeof(char)) < 15);
 720     bool instr_spans_page_boundary =
 721       (align_down((intptr_t) pc ^ (intptr_t) addr,
 722                        (intptr_t) page_size) > 0);
 723 
 724     if (pc == addr || (pc_is_near_addr && instr_spans_page_boundary)) {
 725       static volatile address last_addr =
 726         (address) os::non_memory_address_word();
 727 
 728       // In conservative mode, don't unguard unless the address is in the VM
 729       if (addr != last_addr &&
 730           (UnguardOnExecutionViolation > 1 || os::address_is_in_vm(addr))) {
 731 
 732         // Set memory to RWX and retry
 733         address page_start = align_down(addr, page_size);
 734         bool res = os::protect_memory((char*) page_start, page_size,
 735                                       os::MEM_PROT_RWX);
 736 
 737         log_debug(os)("Execution protection violation "
 738                       "at " INTPTR_FORMAT
 739                       ", unguarding " INTPTR_FORMAT ": %s, errno=%d", p2i(addr),
 740                       p2i(page_start), (res ? "success" : "failed"), errno);
 741         stub = pc;
 742 
 743         // Set last_addr so if we fault again at the same address, we don't end
 744         // up in an endless loop.
 745         //
 746         // There are two potential complications here.  Two threads trapping at
 747         // the same address at the same time could cause one of the threads to
 748         // think it already unguarded, and abort the VM.  Likely very rare.
 749         //
 750         // The other race involves two threads alternately trapping at
 751         // different addresses and failing to unguard the page, resulting in
 752         // an endless loop.  This condition is probably even more unlikely than
 753         // the first.
 754         //
 755         // Although both cases could be avoided by using locks or thread local
 756         // last_addr, these solutions are unnecessary complication: this
 757         // handler is a best-effort safety net, not a complete solution.  It is
 758         // disabled by default and should only be used as a workaround in case
 759         // we missed any no-execute-unsafe VM code.
 760 
 761         last_addr = addr;
 762       }
 763     }
 764   }
 765 #endif // !AMD64
 766 
 767   if (stub != NULL) {
 768     // save all thread context in case we need to restore it
 769     if (thread != NULL) thread->set_saved_exception_pc(pc);
 770 
 771     os::Bsd::ucontext_set_pc(uc, stub);
 772     return true;
 773   }
 774 
 775   // signal-chaining
 776   if (os::Bsd::chained_handler(sig, info, ucVoid)) {
 777      return true;
 778   }
 779 
 780   if (!abort_if_unrecognized) {
 781     // caller wants another chance, so give it to him
 782     return false;
 783   }
 784 
 785   if (pc == NULL && uc != NULL) {
 786     pc = os::Bsd::ucontext_get_pc(uc);
 787   }
 788 
 789   // unmask current signal
 790   sigset_t newset;
 791   sigemptyset(&newset);
 792   sigaddset(&newset, sig);
 793   sigprocmask(SIG_UNBLOCK, &newset, NULL);
 794 
 795   VMError::report_and_die(t, sig, pc, info, ucVoid);
 796 
 797   ShouldNotReachHere();
 798   return false;
 799 }
 800 
 801 // From solaris_i486.s ported to bsd_i486.s
 802 extern "C" void fixcw();
 803 
 804 void os::Bsd::init_thread_fpu_state(void) {
 805 #ifndef AMD64
 806   // Set fpu to 53 bit precision. This happens too early to use a stub.
 807   fixcw();
 808 #endif // !AMD64
 809 }
 810 
 811 
 812 // Check that the bsd kernel version is 2.4 or higher since earlier
 813 // versions do not support SSE without patches.
 814 bool os::supports_sse() {
 815   return true;
 816 }
 817 
 818 bool os::is_allocatable(size_t bytes) {
 819 #ifdef AMD64
 820   // unused on amd64?
 821   return true;
 822 #else
 823 
 824   if (bytes < 2 * G) {
 825     return true;
 826   }
 827 
 828   char* addr = reserve_memory(bytes, NULL);
 829 
 830   if (addr != NULL) {
 831     release_memory(addr, bytes);
 832   }
 833 
 834   return addr != NULL;
 835 #endif // AMD64
 836 }
 837 
 838 ////////////////////////////////////////////////////////////////////////////////
 839 // thread stack
 840 
 841 // Minimum usable stack sizes required to get to user code. Space for
 842 // HotSpot guard pages is added later.
 843 size_t os::Posix::_compiler_thread_min_stack_allowed = 48 * K;
 844 size_t os::Posix::_java_thread_min_stack_allowed = 48 * K;
 845 #ifdef _LP64
 846 size_t os::Posix::_vm_internal_thread_min_stack_allowed = 64 * K;
 847 #else
 848 size_t os::Posix::_vm_internal_thread_min_stack_allowed = (48 DEBUG_ONLY(+ 4)) * K;
 849 #endif // _LP64
 850 
 851 #ifndef AMD64
 852 #ifdef __GNUC__
 853 #define GET_GS() ({int gs; __asm__ volatile("movw %%gs, %w0":"=q"(gs)); gs&0xffff;})
 854 #endif
 855 #endif // AMD64
 856 
 857 // return default stack size for thr_type
 858 size_t os::Posix::default_stack_size(os::ThreadType thr_type) {
 859   // default stack size (compiler thread needs larger stack)
 860 #ifdef AMD64
 861   size_t s = (thr_type == os::compiler_thread ? 4 * M : 1 * M);
 862 #else
 863   size_t s = (thr_type == os::compiler_thread ? 2 * M : 512 * K);
 864 #endif // AMD64
 865   return s;
 866 }
 867 
 868 
 869 // Java thread:
 870 //
 871 //   Low memory addresses
 872 //    +------------------------+
 873 //    |                        |\  Java thread created by VM does not have glibc
 874 //    |    glibc guard page    | - guard, attached Java thread usually has
 875 //    |                        |/  1 glibc guard page.
 876 // P1 +------------------------+ Thread::stack_base() - Thread::stack_size()
 877 //    |                        |\
 878 //    |  HotSpot Guard Pages   | - red, yellow and reserved pages
 879 //    |                        |/
 880 //    +------------------------+ JavaThread::stack_reserved_zone_base()
 881 //    |                        |\
 882 //    |      Normal Stack      | -
 883 //    |                        |/
 884 // P2 +------------------------+ Thread::stack_base()
 885 //
 886 // Non-Java thread:
 887 //
 888 //   Low memory addresses
 889 //    +------------------------+
 890 //    |                        |\
 891 //    |  glibc guard page      | - usually 1 page
 892 //    |                        |/
 893 // P1 +------------------------+ Thread::stack_base() - Thread::stack_size()
 894 //    |                        |\
 895 //    |      Normal Stack      | -
 896 //    |                        |/
 897 // P2 +------------------------+ Thread::stack_base()
 898 //
 899 // ** P1 (aka bottom) and size ( P2 = P1 - size) are the address and stack size returned from
 900 //    pthread_attr_getstack()
 901 
 902 static void current_stack_region(address * bottom, size_t * size) {
 903 #ifdef __APPLE__
 904   pthread_t self = pthread_self();
 905   void *stacktop = pthread_get_stackaddr_np(self);
 906   *size = pthread_get_stacksize_np(self);
 907   // workaround for OS X 10.9.0 (Mavericks)
 908   // pthread_get_stacksize_np returns 128 pages even though the actual size is 2048 pages
 909   if (pthread_main_np() == 1) {
 910     if ((*size) < (DEFAULT_MAIN_THREAD_STACK_PAGES * (size_t)getpagesize())) {
 911       char kern_osrelease[256];
 912       size_t kern_osrelease_size = sizeof(kern_osrelease);
 913       int ret = sysctlbyname("kern.osrelease", kern_osrelease, &kern_osrelease_size, NULL, 0);
 914       if (ret == 0) {
 915         // get the major number, atoi will ignore the minor amd micro portions of the version string
 916         if (atoi(kern_osrelease) >= OS_X_10_9_0_KERNEL_MAJOR_VERSION) {
 917           *size = (DEFAULT_MAIN_THREAD_STACK_PAGES*getpagesize());
 918         }
 919       }
 920     }
 921   }
 922   *bottom = (address) stacktop - *size;
 923 #elif defined(__OpenBSD__)
 924   stack_t ss;
 925   int rslt = pthread_stackseg_np(pthread_self(), &ss);
 926 
 927   if (rslt != 0)
 928     fatal("pthread_stackseg_np failed with error = %d", rslt);
 929 
 930   *bottom = (address)((char *)ss.ss_sp - ss.ss_size);
 931   *size   = ss.ss_size;
 932 #else
 933   pthread_attr_t attr;
 934 
 935   int rslt = pthread_attr_init(&attr);
 936 
 937   // JVM needs to know exact stack location, abort if it fails
 938   if (rslt != 0)
 939     fatal("pthread_attr_init failed with error = %d", rslt);
 940 
 941   rslt = pthread_attr_get_np(pthread_self(), &attr);
 942 
 943   if (rslt != 0)
 944     fatal("pthread_attr_get_np failed with error = %d", rslt);
 945 
 946   if (pthread_attr_getstackaddr(&attr, (void **)bottom) != 0 ||
 947     pthread_attr_getstacksize(&attr, size) != 0) {
 948     fatal("Can not locate current stack attributes!");
 949   }
 950 
 951   pthread_attr_destroy(&attr);
 952 #endif
 953   assert(os::current_stack_pointer() >= *bottom &&
 954          os::current_stack_pointer() < *bottom + *size, "just checking");
 955 }
 956 
 957 address os::current_stack_base() {
 958   address bottom;
 959   size_t size;
 960   current_stack_region(&bottom, &size);
 961   return (bottom + size);
 962 }
 963 
 964 size_t os::current_stack_size() {
 965   // stack size includes normal stack and HotSpot guard pages
 966   address bottom;
 967   size_t size;
 968   current_stack_region(&bottom, &size);
 969   return size;
 970 }
 971 
 972 /////////////////////////////////////////////////////////////////////////////
 973 // helper functions for fatal error handler
 974 
 975 void os::print_context(outputStream *st, const void *context) {
 976   if (context == NULL) return;
 977 
 978   const ucontext_t *uc = (const ucontext_t*)context;
 979   st->print_cr("Registers:");
 980 #ifdef AMD64
 981   st->print(  "RAX=" INTPTR_FORMAT, uc->context_rax);
 982   st->print(", RBX=" INTPTR_FORMAT, uc->context_rbx);
 983   st->print(", RCX=" INTPTR_FORMAT, uc->context_rcx);
 984   st->print(", RDX=" INTPTR_FORMAT, uc->context_rdx);
 985   st->cr();
 986   st->print(  "RSP=" INTPTR_FORMAT, uc->context_rsp);
 987   st->print(", RBP=" INTPTR_FORMAT, uc->context_rbp);
 988   st->print(", RSI=" INTPTR_FORMAT, uc->context_rsi);
 989   st->print(", RDI=" INTPTR_FORMAT, uc->context_rdi);
 990   st->cr();
 991   st->print(  "R8 =" INTPTR_FORMAT, uc->context_r8);
 992   st->print(", R9 =" INTPTR_FORMAT, uc->context_r9);
 993   st->print(", R10=" INTPTR_FORMAT, uc->context_r10);
 994   st->print(", R11=" INTPTR_FORMAT, uc->context_r11);
 995   st->cr();
 996   st->print(  "R12=" INTPTR_FORMAT, uc->context_r12);
 997   st->print(", R13=" INTPTR_FORMAT, uc->context_r13);
 998   st->print(", R14=" INTPTR_FORMAT, uc->context_r14);
 999   st->print(", R15=" INTPTR_FORMAT, uc->context_r15);
1000   st->cr();
1001   st->print(  "RIP=" INTPTR_FORMAT, uc->context_rip);
1002   st->print(", EFLAGS=" INTPTR_FORMAT, uc->context_flags);
1003   st->print(", ERR=" INTPTR_FORMAT, uc->context_err);
1004   st->cr();
1005   st->print("  TRAPNO=" INTPTR_FORMAT, uc->context_trapno);
1006 #else
1007   st->print(  "EAX=" INTPTR_FORMAT, uc->context_eax);
1008   st->print(", EBX=" INTPTR_FORMAT, uc->context_ebx);
1009   st->print(", ECX=" INTPTR_FORMAT, uc->context_ecx);
1010   st->print(", EDX=" INTPTR_FORMAT, uc->context_edx);
1011   st->cr();
1012   st->print(  "ESP=" INTPTR_FORMAT, uc->context_esp);
1013   st->print(", EBP=" INTPTR_FORMAT, uc->context_ebp);
1014   st->print(", ESI=" INTPTR_FORMAT, uc->context_esi);
1015   st->print(", EDI=" INTPTR_FORMAT, uc->context_edi);
1016   st->cr();
1017   st->print(  "EIP=" INTPTR_FORMAT, uc->context_eip);
1018   st->print(", EFLAGS=" INTPTR_FORMAT, uc->context_eflags);
1019 #endif // AMD64
1020   st->cr();
1021   st->cr();
1022 
1023   intptr_t *sp = (intptr_t *)os::Bsd::ucontext_get_sp(uc);
1024   st->print_cr("Top of Stack: (sp=" PTR_FORMAT ")", sp);
1025   print_hex_dump(st, (address)sp, (address)(sp + 8*sizeof(intptr_t)), sizeof(intptr_t));
1026   st->cr();
1027 
1028   // Note: it may be unsafe to inspect memory near pc. For example, pc may
1029   // point to garbage if entry point in an nmethod is corrupted. Leave
1030   // this at the end, and hope for the best.
1031   address pc = os::Bsd::ucontext_get_pc(uc);
1032   st->print_cr("Instructions: (pc=" PTR_FORMAT ")", pc);
1033   print_hex_dump(st, pc - 32, pc + 32, sizeof(char));
1034 }
1035 
1036 void os::print_register_info(outputStream *st, const void *context) {
1037   if (context == NULL) return;
1038 
1039   const ucontext_t *uc = (const ucontext_t*)context;
1040 
1041   st->print_cr("Register to memory mapping:");
1042   st->cr();
1043 
1044   // this is horrendously verbose but the layout of the registers in the
1045   // context does not match how we defined our abstract Register set, so
1046   // we can't just iterate through the gregs area
1047 
1048   // this is only for the "general purpose" registers
1049 
1050 #ifdef AMD64
1051   st->print("RAX="); print_location(st, uc->context_rax);
1052   st->print("RBX="); print_location(st, uc->context_rbx);
1053   st->print("RCX="); print_location(st, uc->context_rcx);
1054   st->print("RDX="); print_location(st, uc->context_rdx);
1055   st->print("RSP="); print_location(st, uc->context_rsp);
1056   st->print("RBP="); print_location(st, uc->context_rbp);
1057   st->print("RSI="); print_location(st, uc->context_rsi);
1058   st->print("RDI="); print_location(st, uc->context_rdi);
1059   st->print("R8 ="); print_location(st, uc->context_r8);
1060   st->print("R9 ="); print_location(st, uc->context_r9);
1061   st->print("R10="); print_location(st, uc->context_r10);
1062   st->print("R11="); print_location(st, uc->context_r11);
1063   st->print("R12="); print_location(st, uc->context_r12);
1064   st->print("R13="); print_location(st, uc->context_r13);
1065   st->print("R14="); print_location(st, uc->context_r14);
1066   st->print("R15="); print_location(st, uc->context_r15);
1067 #else
1068   st->print("EAX="); print_location(st, uc->context_eax);
1069   st->print("EBX="); print_location(st, uc->context_ebx);
1070   st->print("ECX="); print_location(st, uc->context_ecx);
1071   st->print("EDX="); print_location(st, uc->context_edx);
1072   st->print("ESP="); print_location(st, uc->context_esp);
1073   st->print("EBP="); print_location(st, uc->context_ebp);
1074   st->print("ESI="); print_location(st, uc->context_esi);
1075   st->print("EDI="); print_location(st, uc->context_edi);
1076 #endif // AMD64
1077 
1078   st->cr();
1079 }
1080 
1081 void os::setup_fpu() {
1082 #ifndef AMD64
1083   address fpu_cntrl = StubRoutines::addr_fpu_cntrl_wrd_std();
1084   __asm__ volatile (  "fldcw (%0)" :
1085                       : "r" (fpu_cntrl) : "memory");
1086 #endif // !AMD64
1087 }
1088 
1089 #ifndef PRODUCT
1090 void os::verify_stack_alignment() {
1091 }
1092 #endif
1093 
1094 int os::extra_bang_size_in_bytes() {
1095   // JDK-8050147 requires the full cache line bang for x86.
1096   return VM_Version::L1_line_size();
1097 }