Mercurial > jdk8-mips64-public > hotspot / file revision

 /*

  * Copyright 1999-2007 Sun Microsystems, Inc.  All Rights Reserved.

  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

  *

  * This code is free software; you can redistribute it and/or modify it

  * under the terms of the GNU General Public License version 2 only, as

  * published by the Free Software Foundation.

  *

  * This code is distributed in the hope that it will be useful, but WITHOUT

  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

  * version 2 for more details (a copy is included in the LICENSE file that

  * accompanied this code).

  *

  * You should have received a copy of the GNU General Public License version

  * 2 along with this work; if not, write to the Free Software Foundation,

  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

  *

  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

  * CA 95054 USA or visit www.sun.com if you need additional information or

  * have any questions.

  *

  */

 // do not include  precompiled  header file

 # include <signal.h>        // needed first to avoid name collision for "std" with SC 5.0

 # include "incls/_os_solaris_sparc.cpp.incl"

 // put OS-includes here

 # include <sys/types.h>

 # include <sys/mman.h>

 # include <pthread.h>

 # include <errno.h>

 # include <dlfcn.h>

 # include <stdio.h>

 # include <unistd.h>

 # include <sys/resource.h>

 # include <thread.h>

 # include <sys/stat.h>

 # include <sys/time.h>

 # include <sys/filio.h>

 # include <sys/utsname.h>

 # include <sys/systeminfo.h>

 # include <sys/socket.h>

 # include <sys/lwp.h>

 # include <pwd.h>

 # include <poll.h>

 # include <sys/lwp.h>

 # define _STRUCTURED_PROC 1  //  this gets us the new structured proc interfaces of 5.6 & later

 # include <sys/procfs.h>     //  see comment in <sys/procfs.h>

 #define MAX_PATH (2 * K)

 // Minimum stack size for the VM.  It's easier to document a constant

 // but it's different for x86 and sparc because the page sizes are different.

 #ifdef _LP64

 size_t os::Solaris::min_stack_allowed = 128*K;

 #else

 size_t os::Solaris::min_stack_allowed = 96*K;

 #endif

 int os::Solaris::max_register_window_saves_before_flushing() {

   // We should detect this at run time. For now, filling

   // in with a constant.

   return 8;

 }

 static void handle_unflushed_register_windows(gwindows_t *win) {

   int restore_count = win->wbcnt;

   int i;

   for(i=0; i<restore_count; i++) {

     address sp = ((address)win->spbuf[i]) + STACK_BIAS;

     address reg_win = (address)&win->wbuf[i];

     memcpy(sp,reg_win,sizeof(struct rwindow));

   }

 }

 char* os::non_memory_address_word() {

   // Must never look like an address returned by reserve_memory,

   // even in its subfields (as defined by the CPU immediate fields,

   // if the CPU splits constants across multiple instructions).

   // On SPARC, 0 != %hi(any real address), because there is no

   // allocation in the first 1Kb of the virtual address space.

   return (char*) 0;

 }

 // Validate a ucontext retrieved from walking a uc_link of a ucontext.

 // There are issues with libthread giving out uc_links for different threads

 // on the same uc_link chain and bad or circular links.

 //

 bool os::Solaris::valid_ucontext(Thread* thread, ucontext_t* valid, ucontext_t* suspect) {

   if (valid >= suspect ||

       valid->uc_stack.ss_flags != suspect->uc_stack.ss_flags ||

       valid->uc_stack.ss_sp    != suspect->uc_stack.ss_sp    ||

       valid->uc_stack.ss_size  != suspect->uc_stack.ss_size) {

     DEBUG_ONLY(tty->print_cr("valid_ucontext: failed test 1");)

     return false;

   }

   if (thread->is_Java_thread()) {

     if (!valid_stack_address(thread, (address)suspect)) {

       DEBUG_ONLY(tty->print_cr("valid_ucontext: uc_link not in thread stack");)

       return false;

     }

     address _sp   = (address)((intptr_t)suspect->uc_mcontext.gregs[REG_SP] + STACK_BIAS);

     if (!valid_stack_address(thread, _sp) ||

         !frame::is_valid_stack_pointer(((JavaThread*)thread)->base_of_stack_pointer(), (intptr_t*)_sp)) {

       DEBUG_ONLY(tty->print_cr("valid_ucontext: stackpointer not in thread stack");)

       return false;

     }

   }

   return true;

 }

 // We will only follow one level of uc_link since there are libthread

 // issues with ucontext linking and it is better to be safe and just

 // let caller retry later.

 ucontext_t* os::Solaris::get_valid_uc_in_signal_handler(Thread *thread,

   ucontext_t *uc) {

   ucontext_t *retuc = NULL;

   // Sometimes the topmost register windows are not properly flushed.

   // i.e., if the kernel would have needed to take a page fault

   if (uc != NULL && uc->uc_mcontext.gwins != NULL) {

     ::handle_unflushed_register_windows(uc->uc_mcontext.gwins);

   }

   if (uc != NULL) {

     if (uc->uc_link == NULL) {

       // cannot validate without uc_link so accept current ucontext

       retuc = uc;

     } else if (os::Solaris::valid_ucontext(thread, uc, uc->uc_link)) {

       // first ucontext is valid so try the next one

       uc = uc->uc_link;

       if (uc->uc_link == NULL) {

         // cannot validate without uc_link so accept current ucontext

         retuc = uc;

       } else if (os::Solaris::valid_ucontext(thread, uc, uc->uc_link)) {

         // the ucontext one level down is also valid so return it

         retuc = uc;

       }

     }

   }

   return retuc;

 }

 // Assumes ucontext is valid

 ExtendedPC os::Solaris::ucontext_get_ExtendedPC(ucontext_t *uc) {

   address pc = (address)uc->uc_mcontext.gregs[REG_PC];

   // set npc to zero to avoid using it for safepoint, good for profiling only

   return ExtendedPC(pc);

 }

 // Assumes ucontext is valid

 intptr_t* os::Solaris::ucontext_get_sp(ucontext_t *uc) {

   return (intptr_t*)((intptr_t)uc->uc_mcontext.gregs[REG_SP] + STACK_BIAS);

 }

 // Solaris X86 only

 intptr_t* os::Solaris::ucontext_get_fp(ucontext_t *uc) {

   ShouldNotReachHere();

   return NULL;

 }

 // For Forte Analyzer AsyncGetCallTrace profiling support - thread

 // is currently interrupted by SIGPROF.

 //

 // ret_fp parameter is only used by Solaris X86.

 //

 // The difference between this and os::fetch_frame_from_context() is that

 // here we try to skip nested signal frames.

 ExtendedPC os::Solaris::fetch_frame_from_ucontext(Thread* thread,

   ucontext_t* uc, intptr_t** ret_sp, intptr_t** ret_fp) {

   assert(thread != NULL, "just checking");

   assert(ret_sp != NULL, "just checking");

   assert(ret_fp == NULL, "just checking");

   ucontext_t *luc = os::Solaris::get_valid_uc_in_signal_handler(thread, uc);

   return os::fetch_frame_from_context(luc, ret_sp, ret_fp);

 }

 // ret_fp parameter is only used by Solaris X86.

 ExtendedPC os::fetch_frame_from_context(void* ucVoid,

                     intptr_t** ret_sp, intptr_t** ret_fp) {

   ExtendedPC  epc;

   ucontext_t *uc = (ucontext_t*)ucVoid;

   if (uc != NULL) {

     epc = os::Solaris::ucontext_get_ExtendedPC(uc);

     if (ret_sp) *ret_sp = os::Solaris::ucontext_get_sp(uc);

   } else {

     // construct empty ExtendedPC for return value checking

     epc = ExtendedPC(NULL);

     if (ret_sp) *ret_sp = (intptr_t *)NULL;

   }

   return epc;

 }

 frame os::fetch_frame_from_context(void* ucVoid) {

   intptr_t* sp;

   intptr_t* fp;

   ExtendedPC epc = fetch_frame_from_context(ucVoid, &sp, &fp);

   return frame(sp, frame::unpatchable, epc.pc());

 }

 frame os::get_sender_for_C_frame(frame* fr) {

   return frame(fr->sender_sp(), frame::unpatchable, fr->sender_pc());

 }

 frame os::current_frame() {

   intptr_t* sp = StubRoutines::Sparc::flush_callers_register_windows_func()();

   frame myframe(sp, frame::unpatchable,

                 CAST_FROM_FN_PTR(address, os::current_frame));

   if (os::is_first_C_frame(&myframe)) {

     // stack is not walkable

     return frame(NULL, NULL, NULL);

   } else {

     return os::get_sender_for_C_frame(&myframe);

   }

 }

 void GetThreadPC_Callback::execute(OSThread::InterruptArguments *args) {

   Thread*     thread = args->thread();

   ucontext_t* uc     = args->ucontext();

   intptr_t* sp;

   assert(ProfileVM && thread->is_VM_thread(), "just checking");

   // Skip the mcontext corruption verification. If if occasionally

   // things get corrupt, it is ok for profiling - we will just get an unresolved

   // function name

   ExtendedPC new_addr((address)uc->uc_mcontext.gregs[REG_PC]);

   _addr = new_addr;

 }

 static int threadgetstate(thread_t tid, int *flags, lwpid_t *lwp, stack_t *ss, gregset_t rs, lwpstatus_t *lwpstatus) {

   char lwpstatusfile[PROCFILE_LENGTH];

   int lwpfd, err;

   if (err = os::Solaris::thr_getstate(tid, flags, lwp, ss, rs))

     return (err);

   if (*flags == TRS_LWPID) {

     sprintf(lwpstatusfile, "/proc/%d/lwp/%d/lwpstatus", getpid(),

             *lwp);

     if ((lwpfd = open(lwpstatusfile, O_RDONLY)) < 0) {

       perror("thr_mutator_status: open lwpstatus");

       return (EINVAL);

     }

     if (pread(lwpfd, lwpstatus, sizeof (lwpstatus_t), (off_t)0) !=

         sizeof (lwpstatus_t)) {

       perror("thr_mutator_status: read lwpstatus");

       (void) close(lwpfd);

       return (EINVAL);

     }

     (void) close(lwpfd);

   }

   return (0);

 }

 bool os::is_allocatable(size_t bytes) {

 #ifdef _LP64

    return true;

 #else

    return (bytes <= (size_t)3835*M);

 #endif

 }

 extern "C" void Fetch32PFI () ;

 extern "C" void Fetch32Resume () ;

 extern "C" void FetchNPFI () ;

 extern "C" void FetchNResume () ;

 extern "C" int JVM_handle_solaris_signal(int signo, siginfo_t* siginfo, void* ucontext, int abort_if_unrecognized);

 int JVM_handle_solaris_signal(int sig, siginfo_t* info, void* ucVoid, int abort_if_unrecognized) {

   ucontext_t* uc = (ucontext_t*) ucVoid;

   Thread* t = ThreadLocalStorage::get_thread_slow();

   SignalHandlerMark shm(t);

   if(sig == SIGPIPE || sig == SIGXFSZ) {

     if (os::Solaris::chained_handler(sig, info, ucVoid)) {

       return true;

     } else {

       if (PrintMiscellaneous && (WizardMode || Verbose)) {

         char buf[64];

         warning("Ignoring %s - see 4229104 or 6499219",

                 os::exception_name(sig, buf, sizeof(buf)));

       }

       return true;

     }

   }

   JavaThread* thread = NULL;

   VMThread* vmthread = NULL;

   if (os::Solaris::signal_handlers_are_installed) {

     if (t != NULL ){

       if(t->is_Java_thread()) {

         thread = (JavaThread*)t;

       }

       else if(t->is_VM_thread()){

         vmthread = (VMThread *)t;

       }

     }

   }

   guarantee(sig != os::Solaris::SIGinterrupt(), "Can not chain VM interrupt signal, try -XX:+UseAltSigs");

   if (sig == os::Solaris::SIGasync()) {

     if (thread) {

       OSThread::InterruptArguments args(thread, uc);

       thread->osthread()->do_interrupt_callbacks_at_interrupt(&args);

       return true;

     } else if (vmthread) {

       OSThread::InterruptArguments args(vmthread, uc);

       vmthread->osthread()->do_interrupt_callbacks_at_interrupt(&args);

       return true;

     } else if (os::Solaris::chained_handler(sig, info, ucVoid)) {

       return true;

     } else {

       // If os::Solaris::SIGasync not chained, and this is a non-vm and

       // non-java thread

       return true;

     }

   }

   if (info == NULL || info->si_code <= 0 || info->si_code == SI_NOINFO) {

     // can't decode this kind of signal

     info = NULL;

   } else {

     assert(sig == info->si_signo, "bad siginfo");

   }

   // decide if this trap can be handled by a stub

   address stub = NULL;

   address pc          = NULL;

   address npc         = NULL;

   //%note os_trap_1

   if (info != NULL && uc != NULL && thread != NULL) {

     // factor me: getPCfromContext

     pc  = (address) uc->uc_mcontext.gregs[REG_PC];

     npc = (address) uc->uc_mcontext.gregs[REG_nPC];

     // SafeFetch() support

     // Implemented with either a fixed set of addresses such

     // as Fetch32*, or with Thread._OnTrap.

     if (uc->uc_mcontext.gregs[REG_PC] == intptr_t(Fetch32PFI)) {

       uc->uc_mcontext.gregs [REG_PC]  = intptr_t(Fetch32Resume) ;

       uc->uc_mcontext.gregs [REG_nPC] = intptr_t(Fetch32Resume) + 4 ;

       return true ;

     }

     if (uc->uc_mcontext.gregs[REG_PC] == intptr_t(FetchNPFI)) {

       uc->uc_mcontext.gregs [REG_PC]  = intptr_t(FetchNResume) ;

       uc->uc_mcontext.gregs [REG_nPC] = intptr_t(FetchNResume) + 4 ;

       return true ;

     }

     // Handle ALL stack overflow variations here

     if (sig == SIGSEGV && info->si_code == SEGV_ACCERR) {

       address addr = (address) info->si_addr;

       if (thread->in_stack_yellow_zone(addr)) {

         thread->disable_stack_yellow_zone();

         // Sometimes the register windows are not properly flushed.

         if(uc->uc_mcontext.gwins != NULL) {

           ::handle_unflushed_register_windows(uc->uc_mcontext.gwins);

         }

         if (thread->thread_state() == _thread_in_Java) {

           // Throw a stack overflow exception.  Guard pages will be reenabled

           // while unwinding the stack.

           stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::STACK_OVERFLOW);

         } else {

           // Thread was in the vm or native code.  Return and try to finish.

           return true;

         }

       } else if (thread->in_stack_red_zone(addr)) {

         // Fatal red zone violation.  Disable the guard pages and fall through

         // to handle_unexpected_exception way down below.

         thread->disable_stack_red_zone();

         tty->print_raw_cr("An irrecoverable stack overflow has occurred.");

         // Sometimes the register windows are not properly flushed.

         if(uc->uc_mcontext.gwins != NULL) {

           ::handle_unflushed_register_windows(uc->uc_mcontext.gwins);

         }

       }

     }

     if (thread->thread_state() == _thread_in_vm) {

       if (sig == SIGBUS && info->si_code == BUS_OBJERR && thread->doing_unsafe_access()) {

         stub = StubRoutines::handler_for_unsafe_access();

       }

     }

     else if (thread->thread_state() == _thread_in_Java) {

       // Java thread running in Java code => find exception handler if any

       // a fault inside compiled code, the interpreter, or a stub

       // Support Safepoint Polling

       if ( sig == SIGSEGV && (address)info->si_addr == os::get_polling_page() ) {

         stub = SharedRuntime::get_poll_stub(pc);

       }

       // Not needed on x86 solaris because verify_oops doesn't generate

       // SEGV/BUS like sparc does.

       if ( (sig == SIGSEGV || sig == SIGBUS)

            && pc >= MacroAssembler::_verify_oop_implicit_branch[0]

            && pc <  MacroAssembler::_verify_oop_implicit_branch[1] ) {

         stub     =  MacroAssembler::_verify_oop_implicit_branch[2];

         warning("fixed up memory fault in +VerifyOops at address " INTPTR_FORMAT, info->si_addr);

       }

       // This is not factored because on x86 solaris the patching for

       // zombies does not generate a SEGV.

       else if (sig == SIGSEGV && nativeInstruction_at(pc)->is_zombie()) {

         // zombie method (ld [%g0],%o7 instruction)

         stub = SharedRuntime::get_handle_wrong_method_stub();

         // At the stub it needs to look like a call from the caller of this

         // method (not a call from the segv site).

         pc = (address)uc->uc_mcontext.gregs[REG_O7];

       }

       else if (sig == SIGBUS && info->si_code == BUS_OBJERR) {

         // BugId 4454115: A read from a MappedByteBuffer can fault

         // here if the underlying file has been truncated.

         // Do not crash the VM in such a case.

         CodeBlob* cb = CodeCache::find_blob_unsafe(pc);

         nmethod* nm = cb->is_nmethod() ? (nmethod*)cb : NULL;

         if (nm != NULL && nm->has_unsafe_access()) {

           stub = StubRoutines::handler_for_unsafe_access();

         }

       }

       else if (sig == SIGFPE && info->si_code == FPE_INTDIV) {

         // integer divide by zero

         stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO);

       }

       else if (sig == SIGFPE && info->si_code == FPE_FLTDIV) {

         // floating-point divide by zero

         stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO);

       }

 #ifdef COMPILER2

       else if (sig == SIGILL && nativeInstruction_at(pc)->is_ic_miss_trap()) {

 #ifdef ASSERT

   #ifdef TIERED

         CodeBlob* cb = CodeCache::find_blob_unsafe(pc);

         assert(cb->is_compiled_by_c2(), "Wrong compiler");

   #endif // TIERED

 #endif // ASSERT

         // Inline cache missed and user trap "Tne G0+ST_RESERVED_FOR_USER_0+2" taken.

         stub = SharedRuntime::get_ic_miss_stub();

         // At the stub it needs to look like a call from the caller of this

         // method (not a call from the segv site).

         pc = (address)uc->uc_mcontext.gregs[REG_O7];

       }

 #endif  // COMPILER2

       else if (sig == SIGSEGV && info->si_code > 0 && !MacroAssembler::needs_explicit_null_check((intptr_t)info->si_addr)) {

         // Determination of interpreter/vtable stub/compiled code null exception

         stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL);

       }

     }

     // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC kicks in

     // and the heap gets shrunk before the field access.

     if ((sig == SIGSEGV) || (sig == SIGBUS)) {

       address addr = JNI_FastGetField::find_slowcase_pc(pc);

       if (addr != (address)-1) {

         stub = addr;

       }

     }

     // Check to see if we caught the safepoint code in the

     // process of write protecting the memory serialization page.

     // It write enables the page immediately after protecting it

     // so just return.

     if ((sig == SIGSEGV) &&

         os::is_memory_serialize_page(thread, (address)info->si_addr)) {

       // Block current thread until the memory serialize page permission restored.

       os::block_on_serialize_page_trap();

       return true;

     }

   }

   if (stub != NULL) {

     // save all thread context in case we need to restore it

     thread->set_saved_exception_pc(pc);

     thread->set_saved_exception_npc(npc);

     // simulate a branch to the stub (a "call" in the safepoint stub case)

     // factor me: setPC

     uc->uc_mcontext.gregs[REG_PC ] = (greg_t)stub;

     uc->uc_mcontext.gregs[REG_nPC] = (greg_t)(stub + 4);

 #ifndef PRODUCT

     if (TraceJumps) thread->record_jump(stub, NULL, __FILE__, __LINE__);

 #endif /* PRODUCT */

     return true;

   }

   // signal-chaining

   if (os::Solaris::chained_handler(sig, info, ucVoid)) {

     return true;

   }

   if (!abort_if_unrecognized) {

     // caller wants another chance, so give it to him

     return false;

   }

   if (!os::Solaris::libjsig_is_loaded) {

     struct sigaction oldAct;

     sigaction(sig, (struct sigaction *)0, &oldAct);

     if (oldAct.sa_sigaction != signalHandler) {

       void* sighand = oldAct.sa_sigaction ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)

                                           : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);

       warning("Unexpected Signal %d occurred under user-defined signal handler " INTPTR_FORMAT, sig, (intptr_t)sighand);

     }

   }

   if (pc == NULL && uc != NULL) {

     pc = (address) uc->uc_mcontext.gregs[REG_PC];

   }

   // unmask current signal

   sigset_t newset;

   sigemptyset(&newset);

   sigaddset(&newset, sig);

   sigprocmask(SIG_UNBLOCK, &newset, NULL);

   VMError err(t, sig, pc, info, ucVoid);

   err.report_and_die();

   ShouldNotReachHere();

 }

 void os::print_context(outputStream *st, void *context) {

   if (context == NULL) return;

   ucontext_t *uc = (ucontext_t*)context;

   st->print_cr("Registers:");

   st->print_cr(" O0=" INTPTR_FORMAT " O1=" INTPTR_FORMAT

                " O2=" INTPTR_FORMAT " O3=" INTPTR_FORMAT,

                  uc->uc_mcontext.gregs[REG_O0],

                  uc->uc_mcontext.gregs[REG_O1],

                  uc->uc_mcontext.gregs[REG_O2],

                  uc->uc_mcontext.gregs[REG_O3]);

   st->print_cr(" O4=" INTPTR_FORMAT " O5=" INTPTR_FORMAT

                " O6=" INTPTR_FORMAT " O7=" INTPTR_FORMAT,

             uc->uc_mcontext.gregs[REG_O4],

             uc->uc_mcontext.gregs[REG_O5],

             uc->uc_mcontext.gregs[REG_O6],

             uc->uc_mcontext.gregs[REG_O7]);

   st->print_cr(" G1=" INTPTR_FORMAT " G2=" INTPTR_FORMAT

                " G3=" INTPTR_FORMAT " G4=" INTPTR_FORMAT,

             uc->uc_mcontext.gregs[REG_G1],

             uc->uc_mcontext.gregs[REG_G2],

             uc->uc_mcontext.gregs[REG_G3],

             uc->uc_mcontext.gregs[REG_G4]);

   st->print_cr(" G5=" INTPTR_FORMAT " G6=" INTPTR_FORMAT

                " G7=" INTPTR_FORMAT " Y=" INTPTR_FORMAT,

             uc->uc_mcontext.gregs[REG_G5],

             uc->uc_mcontext.gregs[REG_G6],

             uc->uc_mcontext.gregs[REG_G7],

             uc->uc_mcontext.gregs[REG_Y]);

   st->print_cr(" PC=" INTPTR_FORMAT " nPC=" INTPTR_FORMAT,

             uc->uc_mcontext.gregs[REG_PC],

             uc->uc_mcontext.gregs[REG_nPC]);

   st->cr();

   st->cr();

   intptr_t *sp = (intptr_t *)os::Solaris::ucontext_get_sp(uc);

   st->print_cr("Top of Stack: (sp=" PTR_FORMAT ")", sp);

   print_hex_dump(st, (address)sp, (address)(sp + 32), sizeof(intptr_t));

   st->cr();

   // Note: it may be unsafe to inspect memory near pc. For example, pc may

   // point to garbage if entry point in an nmethod is corrupted. Leave

   // this at the end, and hope for the best.

   ExtendedPC epc = os::Solaris::ucontext_get_ExtendedPC(uc);

   address pc = epc.pc();

   st->print_cr("Instructions: (pc=" PTR_FORMAT ")", pc);

   print_hex_dump(st, pc - 16, pc + 16, sizeof(char));

 }

 void os::Solaris::init_thread_fpu_state(void) {

     // Nothing needed on Sparc.

 }

 #if !defined(COMPILER2) && !defined(_LP64)

 // These routines are the initial value of atomic_xchg_entry(),

 // atomic_cmpxchg_entry(), atomic_add_entry() and fence_entry()

 // until initialization is complete.

 // TODO - remove when the VM drops support for V8.

 typedef jint  xchg_func_t        (jint,  volatile jint*);

 typedef jint  cmpxchg_func_t     (jint,  volatile jint*,  jint);

 typedef jlong cmpxchg_long_func_t(jlong, volatile jlong*, jlong);

 typedef jint  add_func_t         (jint,  volatile jint*);

 typedef void  fence_func_t       ();

 jint os::atomic_xchg_bootstrap(jint exchange_value, volatile jint* dest) {

   // try to use the stub:

   xchg_func_t* func = CAST_TO_FN_PTR(xchg_func_t*, StubRoutines::atomic_xchg_entry());

   if (func != NULL) {

     os::atomic_xchg_func = func;

     return (*func)(exchange_value, dest);

   }

   assert(Threads::number_of_threads() == 0, "for bootstrap only");

   jint old_value = *dest;

   *dest = exchange_value;

   return old_value;

 }

 jint os::atomic_cmpxchg_bootstrap(jint exchange_value, volatile jint* dest, jint compare_value) {

   // try to use the stub:

   cmpxchg_func_t* func = CAST_TO_FN_PTR(cmpxchg_func_t*, StubRoutines::atomic_cmpxchg_entry());

   if (func != NULL) {

     os::atomic_cmpxchg_func = func;

     return (*func)(exchange_value, dest, compare_value);

   }

   assert(Threads::number_of_threads() == 0, "for bootstrap only");

   jint old_value = *dest;

   if (old_value == compare_value)

     *dest = exchange_value;

   return old_value;

 }

 jlong os::atomic_cmpxchg_long_bootstrap(jlong exchange_value, volatile jlong* dest, jlong compare_value) {

   // try to use the stub:

   cmpxchg_long_func_t* func = CAST_TO_FN_PTR(cmpxchg_long_func_t*, StubRoutines::atomic_cmpxchg_long_entry());

   if (func != NULL) {

     os::atomic_cmpxchg_long_func = func;

     return (*func)(exchange_value, dest, compare_value);

   }

   assert(Threads::number_of_threads() == 0, "for bootstrap only");

   jlong old_value = *dest;

   if (old_value == compare_value)

     *dest = exchange_value;

   return old_value;

 }

 jint os::atomic_add_bootstrap(jint add_value, volatile jint* dest) {

   // try to use the stub:

   add_func_t* func = CAST_TO_FN_PTR(add_func_t*, StubRoutines::atomic_add_entry());

   if (func != NULL) {

     os::atomic_add_func = func;

     return (*func)(add_value, dest);

   }

   assert(Threads::number_of_threads() == 0, "for bootstrap only");

   return (*dest) += add_value;

 }

 void os::fence_bootstrap() {

   // try to use the stub:

   fence_func_t* func = CAST_TO_FN_PTR(fence_func_t*, StubRoutines::fence_entry());

   if (func != NULL) {

     os::fence_func = func;

     (*func)();

     return;

   }

   assert(Threads::number_of_threads() == 0, "for bootstrap only");

   // don't have to do anything for a single thread

 }

 xchg_func_t*         os::atomic_xchg_func         = os::atomic_xchg_bootstrap;

 cmpxchg_func_t*      os::atomic_cmpxchg_func      = os::atomic_cmpxchg_bootstrap;

 cmpxchg_long_func_t* os::atomic_cmpxchg_long_func = os::atomic_cmpxchg_long_bootstrap;

 add_func_t*          os::atomic_add_func          = os::atomic_add_bootstrap;

 fence_func_t*        os::fence_func               = os::fence_bootstrap;

 #endif // !_LP64 && !COMPILER2

 #if defined(__sparc) && defined(COMPILER2) && defined(_GNU_SOURCE)

  // See file build/solaris/makefiles/$compiler.make

  // For compiler1 the architecture is v8 and frps isn't present in v8

  extern "C"  void _mark_fpu_nosave() {

    __asm__ __volatile__ ("wr %%g0, 0, %%fprs \n\t" : : :);

   }

 #endif //defined(__sparc) && defined(COMPILER2)