aoqi@0: /*
aoqi@0:  * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
aoqi@0:  * Copyright 2012, 2014 SAP AG. All rights reserved.
aoqi@0:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
aoqi@0:  *
aoqi@0:  * This code is free software; you can redistribute it and/or modify it
aoqi@0:  * under the terms of the GNU General Public License version 2 only, as
aoqi@0:  * published by the Free Software Foundation.
aoqi@0:  *
aoqi@0:  * This code is distributed in the hope that it will be useful, but WITHOUT
aoqi@0:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
aoqi@0:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
aoqi@0:  * version 2 for more details (a copy is included in the LICENSE file that
aoqi@0:  * accompanied this code).
aoqi@0:  *
aoqi@0:  * You should have received a copy of the GNU General Public License version
aoqi@0:  * 2 along with this work; if not, write to the Free Software Foundation,
aoqi@0:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
aoqi@0:  *
aoqi@0:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
aoqi@0:  * or visit www.oracle.com if you need additional information or have any
aoqi@0:  * questions.
aoqi@0:  *
aoqi@0:  */
aoqi@0: 
aoqi@0: // no precompiled headers
aoqi@0: #include "assembler_ppc.inline.hpp"
aoqi@0: #include "classfile/classLoader.hpp"
aoqi@0: #include "classfile/systemDictionary.hpp"
aoqi@0: #include "classfile/vmSymbols.hpp"
aoqi@0: #include "code/icBuffer.hpp"
aoqi@0: #include "code/vtableStubs.hpp"
aoqi@0: #include "interpreter/interpreter.hpp"
aoqi@0: #include "jvm_aix.h"
aoqi@0: #include "memory/allocation.inline.hpp"
aoqi@0: #include "mutex_aix.inline.hpp"
aoqi@0: #include "nativeInst_ppc.hpp"
aoqi@0: #include "os_share_aix.hpp"
aoqi@0: #include "prims/jniFastGetField.hpp"
aoqi@0: #include "prims/jvm.h"
aoqi@0: #include "prims/jvm_misc.hpp"
aoqi@0: #include "runtime/arguments.hpp"
aoqi@0: #include "runtime/extendedPC.hpp"
aoqi@0: #include "runtime/frame.inline.hpp"
aoqi@0: #include "runtime/interfaceSupport.hpp"
aoqi@0: #include "runtime/java.hpp"
aoqi@0: #include "runtime/javaCalls.hpp"
aoqi@0: #include "runtime/mutexLocker.hpp"
aoqi@0: #include "runtime/osThread.hpp"
aoqi@0: #include "runtime/sharedRuntime.hpp"
aoqi@0: #include "runtime/stubRoutines.hpp"
aoqi@0: #include "runtime/thread.inline.hpp"
aoqi@0: #include "runtime/timer.hpp"
aoqi@0: #include "utilities/events.hpp"
aoqi@0: #include "utilities/vmError.hpp"
aoqi@0: #ifdef COMPILER1
aoqi@0: #include "c1/c1_Runtime1.hpp"
aoqi@0: #endif
aoqi@0: #ifdef COMPILER2
aoqi@0: #include "opto/runtime.hpp"
aoqi@0: #endif
aoqi@0: 
aoqi@0: // put OS-includes here
aoqi@0: # include <ucontext.h>
aoqi@0: 
aoqi@0: address os::current_stack_pointer() {
aoqi@0:   address csp;
aoqi@0: 
aoqi@0: #if !defined(USE_XLC_BUILTINS)
aoqi@0:   // inline assembly for `mr regno(csp), R1_SP':
aoqi@0:   __asm__ __volatile__ ("mr %0, 1":"=r"(csp):);
aoqi@0: #else
aoqi@0:   csp = (address) __builtin_frame_address(0);
aoqi@0: #endif
aoqi@0: 
aoqi@0:   return csp;
aoqi@0: }
aoqi@0: 
aoqi@0: char* os::non_memory_address_word() {
aoqi@0:   // Must never look like an address returned by reserve_memory,
aoqi@0:   // even in its subfields (as defined by the CPU immediate fields,
aoqi@0:   // if the CPU splits constants across multiple instructions).
aoqi@0: 
aoqi@0:   return (char*) -1;
aoqi@0: }
aoqi@0: 
aoqi@0: // OS specific thread initialization
aoqi@0: //
aoqi@0: // Calculate and store the limits of the memory stack.
aoqi@0: void os::initialize_thread(Thread *thread) { }
aoqi@0: 
aoqi@0: // Frame information (pc, sp, fp) retrieved via ucontext
aoqi@0: // always looks like a C-frame according to the frame
aoqi@0: // conventions in frame_ppc64.hpp.
aoqi@0: address os::Aix::ucontext_get_pc(ucontext_t * uc) {
aoqi@0:   return (address)uc->uc_mcontext.jmp_context.iar;
aoqi@0: }
aoqi@0: 
aoqi@0: intptr_t* os::Aix::ucontext_get_sp(ucontext_t * uc) {
aoqi@0:   // gpr1 holds the stack pointer on aix
aoqi@0:   return (intptr_t*)uc->uc_mcontext.jmp_context.gpr[1/*REG_SP*/];
aoqi@0: }
aoqi@0: 
aoqi@0: intptr_t* os::Aix::ucontext_get_fp(ucontext_t * uc) {
aoqi@0:   return NULL;
aoqi@0: }
aoqi@0: 
aoqi@0: void os::Aix::ucontext_set_pc(ucontext_t* uc, address new_pc) {
aoqi@0:   uc->uc_mcontext.jmp_context.iar = (uint64_t) new_pc;
aoqi@0: }
aoqi@0: 
aoqi@0: ExtendedPC os::fetch_frame_from_context(void* ucVoid,
aoqi@0:                                         intptr_t** ret_sp, intptr_t** ret_fp) {
aoqi@0: 
aoqi@0:   ExtendedPC  epc;
aoqi@0:   ucontext_t* uc = (ucontext_t*)ucVoid;
aoqi@0: 
aoqi@0:   if (uc != NULL) {
aoqi@0:     epc = ExtendedPC(os::Aix::ucontext_get_pc(uc));
aoqi@0:     if (ret_sp) *ret_sp = os::Aix::ucontext_get_sp(uc);
aoqi@0:     if (ret_fp) *ret_fp = os::Aix::ucontext_get_fp(uc);
aoqi@0:   } else {
aoqi@0:     // construct empty ExtendedPC for return value checking
aoqi@0:     epc = ExtendedPC(NULL);
aoqi@0:     if (ret_sp) *ret_sp = (intptr_t *)NULL;
aoqi@0:     if (ret_fp) *ret_fp = (intptr_t *)NULL;
aoqi@0:   }
aoqi@0: 
aoqi@0:   return epc;
aoqi@0: }
aoqi@0: 
aoqi@0: frame os::fetch_frame_from_context(void* ucVoid) {
aoqi@0:   intptr_t* sp;
aoqi@0:   intptr_t* fp;
aoqi@0:   ExtendedPC epc = fetch_frame_from_context(ucVoid, &sp, &fp);
aoqi@0:   // Avoid crash during crash if pc broken.
aoqi@0:   if (epc.pc()) {
aoqi@0:     frame fr(sp, epc.pc());
aoqi@0:     return fr;
aoqi@0:   }
aoqi@0:   frame fr(sp);
aoqi@0:   return fr;
aoqi@0: }
aoqi@0: 
aoqi@0: frame os::get_sender_for_C_frame(frame* fr) {
aoqi@0:   if (*fr->sp() == NULL) {
aoqi@0:     // fr is the last C frame
aoqi@0:     return frame(NULL, NULL);
aoqi@0:   }
aoqi@0:   return frame(fr->sender_sp(), fr->sender_pc());
aoqi@0: }
aoqi@0: 
aoqi@0: 
aoqi@0: frame os::current_frame() {
aoqi@0:   intptr_t* csp = (intptr_t*) *((intptr_t*) os::current_stack_pointer());
aoqi@0:   // hack.
aoqi@0:   frame topframe(csp, (address)0x8);
aoqi@0:   // return sender of current topframe which hopefully has pc != NULL.
aoqi@0:   return os::get_sender_for_C_frame(&topframe);
aoqi@0: }
aoqi@0: 
aoqi@0: // Utility functions
aoqi@0: 
aoqi@0: extern "C" JNIEXPORT int
aoqi@0: JVM_handle_aix_signal(int sig, siginfo_t* info, void* ucVoid, int abort_if_unrecognized) {
aoqi@0: 
aoqi@0:   ucontext_t* uc = (ucontext_t*) ucVoid;
aoqi@0: 
aoqi@0:   Thread* t = ThreadLocalStorage::get_thread_slow();   // slow & steady
aoqi@0: 
aoqi@0:   SignalHandlerMark shm(t);
aoqi@0: 
aoqi@0:   // Note: it's not uncommon that JNI code uses signal/sigset to install
aoqi@0:   // then restore certain signal handler (e.g. to temporarily block SIGPIPE,
aoqi@0:   // or have a SIGILL handler when detecting CPU type). When that happens,
aoqi@0:   // JVM_handle_aix_signal() might be invoked with junk info/ucVoid. To
aoqi@0:   // avoid unnecessary crash when libjsig is not preloaded, try handle signals
aoqi@0:   // that do not require siginfo/ucontext first.
aoqi@0: 
aoqi@0:   if (sig == SIGPIPE) {
aoqi@0:     if (os::Aix::chained_handler(sig, info, ucVoid)) {
aoqi@0:       return 1;
aoqi@0:     } else {
aoqi@0:       if (PrintMiscellaneous && (WizardMode || Verbose)) {
aoqi@0:         warning("Ignoring SIGPIPE - see bug 4229104");
aoqi@0:       }
aoqi@0:       return 1;
aoqi@0:     }
aoqi@0:   }
aoqi@0: 
aoqi@0:   JavaThread* thread = NULL;
aoqi@0:   VMThread* vmthread = NULL;
aoqi@0:   if (os::Aix::signal_handlers_are_installed) {
aoqi@0:     if (t != NULL) {
aoqi@0:       if(t->is_Java_thread()) {
aoqi@0:         thread = (JavaThread*)t;
aoqi@0:       }
aoqi@0:       else if(t->is_VM_thread()) {
aoqi@0:         vmthread = (VMThread *)t;
aoqi@0:       }
aoqi@0:     }
aoqi@0:   }
aoqi@0: 
aoqi@0:   // Decide if this trap can be handled by a stub.
aoqi@0:   address stub = NULL;
aoqi@0: 
aoqi@0:   // retrieve program counter
aoqi@0:   address const pc = uc ? os::Aix::ucontext_get_pc(uc) : NULL;
aoqi@0: 
aoqi@0:   // retrieve crash address
aoqi@0:   address const addr = info ? (const address) info->si_addr : NULL;
aoqi@0: 
aoqi@0:   // SafeFetch 32 handling:
aoqi@0:   // - make it work if _thread is null
aoqi@0:   // - make it use the standard os::...::ucontext_get/set_pc APIs
aoqi@0:   if (uc) {
aoqi@0:     address const pc = os::Aix::ucontext_get_pc(uc);
aoqi@0:     if (pc && StubRoutines::is_safefetch_fault(pc)) {
aoqi@0:       os::Aix::ucontext_set_pc(uc, StubRoutines::continuation_for_safefetch_fault(pc));
aoqi@0:       return true;
aoqi@0:     }
aoqi@0:   }
aoqi@0: 
aoqi@0:   // Handle SIGDANGER right away. AIX would raise SIGDANGER whenever available swap
aoqi@0:   // space falls below 30%. This is only a chance for the process to gracefully abort.
aoqi@0:   // We can't hope to proceed after SIGDANGER since SIGKILL tailgates.
aoqi@0:   if (sig == SIGDANGER) {
aoqi@0:     goto report_and_die;
aoqi@0:   }
aoqi@0: 
aoqi@0:   if (info == NULL || uc == NULL || thread == NULL && vmthread == NULL) {
aoqi@0:     goto run_chained_handler;
aoqi@0:   }
aoqi@0: 
aoqi@0:   // If we are a java thread...
aoqi@0:   if (thread != NULL) {
aoqi@0: 
aoqi@0:     // Handle ALL stack overflow variations here
aoqi@0:     if (sig == SIGSEGV && (addr < thread->stack_base() &&
aoqi@0:                            addr >= thread->stack_base() - thread->stack_size())) {
aoqi@0:       // stack overflow
aoqi@0:       //
aoqi@0:       // If we are in a yellow zone and we are inside java, we disable the yellow zone and
aoqi@0:       // throw a stack overflow exception.
aoqi@0:       // If we are in native code or VM C code, we report-and-die. The original coding tried
aoqi@0:       // to continue with yellow zone disabled, but that doesn't buy us much and prevents
aoqi@0:       // hs_err_pid files.
aoqi@0:       if (thread->in_stack_yellow_zone(addr)) {
aoqi@0:         thread->disable_stack_yellow_zone();
aoqi@0:         if (thread->thread_state() == _thread_in_Java) {
aoqi@0:           // Throw a stack overflow exception.
aoqi@0:           // Guard pages will be reenabled while unwinding the stack.
aoqi@0:           stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::STACK_OVERFLOW);
aoqi@0:           goto run_stub;
aoqi@0:         } else {
aoqi@0:           // Thread was in the vm or native code. Return and try to finish.
aoqi@0:           return 1;
aoqi@0:         }
aoqi@0:       } else if (thread->in_stack_red_zone(addr)) {
aoqi@0:         // Fatal red zone violation. Disable the guard pages and fall through
aoqi@0:         // to handle_unexpected_exception way down below.
aoqi@0:         thread->disable_stack_red_zone();
aoqi@0:         tty->print_raw_cr("An irrecoverable stack overflow has occurred.");
aoqi@0:         goto report_and_die;
aoqi@0:       } else {
aoqi@0:         // This means a segv happened inside our stack, but not in
aoqi@0:         // the guarded zone. I'd like to know when this happens,
aoqi@0:         tty->print_raw_cr("SIGSEGV happened inside stack but outside yellow and red zone.");
aoqi@0:         goto report_and_die;
aoqi@0:       }
aoqi@0: 
aoqi@0:     } // end handle SIGSEGV inside stack boundaries
aoqi@0: 
aoqi@0:     if (thread->thread_state() == _thread_in_Java) {
aoqi@0:       // Java thread running in Java code
aoqi@0: 
aoqi@0:       // The following signals are used for communicating VM events:
aoqi@0:       //
aoqi@0:       // SIGILL: the compiler generates illegal opcodes
aoqi@0:       //   at places where it wishes to interrupt the VM:
aoqi@0:       //   Safepoints, Unreachable Code, Entry points of Zombie methods,
aoqi@0:       //    This results in a SIGILL with (*pc) == inserted illegal instruction.
aoqi@0:       //
aoqi@0:       //   (so, SIGILLs with a pc inside the zero page are real errors)
aoqi@0:       //
aoqi@0:       // SIGTRAP:
aoqi@0:       //   The ppc trap instruction raises a SIGTRAP and is very efficient if it
aoqi@0:       //   does not trap. It is used for conditional branches that are expected
aoqi@0:       //   to be never taken. These are:
aoqi@0:       //     - zombie methods
aoqi@0:       //     - IC (inline cache) misses.
aoqi@0:       //     - null checks leading to UncommonTraps.
aoqi@0:       //     - range checks leading to Uncommon Traps.
aoqi@0:       //   On Aix, these are especially null checks, as the ImplicitNullCheck
aoqi@0:       //   optimization works only in rare cases, as the page at address 0 is only
aoqi@0:       //   write protected.      //
aoqi@0:       //   Note: !UseSIGTRAP is used to prevent SIGTRAPS altogether, to facilitate debugging.
aoqi@0:       //
aoqi@0:       // SIGSEGV:
aoqi@0:       //   used for safe point polling:
aoqi@0:       //     To notify all threads that they have to reach a safe point, safe point polling is used:
aoqi@0:       //     All threads poll a certain mapped memory page. Normally, this page has read access.
aoqi@0:       //     If the VM wants to inform the threads about impending safe points, it puts this
aoqi@0:       //     page to read only ("poisens" the page), and the threads then reach a safe point.
aoqi@0:       //   used for null checks:
aoqi@0:       //     If the compiler finds a store it uses it for a null check. Unfortunately this
aoqi@0:       //     happens rarely.  In heap based and disjoint base compressd oop modes also loads
aoqi@0:       //     are used for null checks.
aoqi@0: 
aoqi@0:       // A VM-related SIGILL may only occur if we are not in the zero page.
aoqi@0:       // On AIX, we get a SIGILL if we jump to 0x0 or to somewhere else
aoqi@0:       // in the zero page, because it is filled with 0x0. We ignore
aoqi@0:       // explicit SIGILLs in the zero page.
aoqi@0:       if (sig == SIGILL && (pc < (address) 0x200)) {
aoqi@0:         if (TraceTraps) {
aoqi@0:           tty->print_raw_cr("SIGILL happened inside zero page.");
aoqi@0:         }
aoqi@0:         goto report_and_die;
aoqi@0:       }
aoqi@0: 
aoqi@0:       // Handle signal from NativeJump::patch_verified_entry().
aoqi@0:       if (( TrapBasedNotEntrantChecks && sig == SIGTRAP && nativeInstruction_at(pc)->is_sigtrap_zombie_not_entrant()) ||
aoqi@0:           (!TrapBasedNotEntrantChecks && sig == SIGILL  && nativeInstruction_at(pc)->is_sigill_zombie_not_entrant())) {
aoqi@0:         if (TraceTraps) {
aoqi@0:           tty->print_cr("trap: zombie_not_entrant (%s)", (sig == SIGTRAP) ? "SIGTRAP" : "SIGILL");
aoqi@0:         }
aoqi@0:         stub = SharedRuntime::get_handle_wrong_method_stub();
aoqi@0:         goto run_stub;
aoqi@0:       }
aoqi@0: 
aoqi@0:       else if (sig == SIGSEGV && os::is_poll_address(addr)) {
aoqi@0:         if (TraceTraps) {
aoqi@0:           tty->print_cr("trap: safepoint_poll at " INTPTR_FORMAT " (SIGSEGV)", pc);
aoqi@0:         }
aoqi@0:         stub = SharedRuntime::get_poll_stub(pc);
aoqi@0:         goto run_stub;
aoqi@0:       }
aoqi@0: 
aoqi@0:       // SIGTRAP-based ic miss check in compiled code.
aoqi@0:       else if (sig == SIGTRAP && TrapBasedICMissChecks &&
aoqi@0:                nativeInstruction_at(pc)->is_sigtrap_ic_miss_check()) {
aoqi@0:         if (TraceTraps) {
aoqi@0:           tty->print_cr("trap: ic_miss_check at " INTPTR_FORMAT " (SIGTRAP)", pc);
aoqi@0:         }
aoqi@0:         stub = SharedRuntime::get_ic_miss_stub();
aoqi@0:         goto run_stub;
aoqi@0:       }
aoqi@0: 
aoqi@0:       // SIGTRAP-based implicit null check in compiled code.
aoqi@0:       else if (sig == SIGTRAP && TrapBasedNullChecks &&
aoqi@0:                nativeInstruction_at(pc)->is_sigtrap_null_check()) {
aoqi@0:         if (TraceTraps) {
aoqi@0:           tty->print_cr("trap: null_check at " INTPTR_FORMAT " (SIGTRAP)", pc);
aoqi@0:         }
aoqi@0:         stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL);
aoqi@0:         goto run_stub;
aoqi@0:       }
aoqi@0: 
aoqi@0:       // SIGSEGV-based implicit null check in compiled code.
aoqi@0:       else if (sig == SIGSEGV && ImplicitNullChecks &&
aoqi@0:                CodeCache::contains((void*) pc) &&
aoqi@0:                !MacroAssembler::needs_explicit_null_check((intptr_t) info->si_addr)) {
aoqi@0:         if (TraceTraps) {
aoqi@0:           tty->print_cr("trap: null_check at " INTPTR_FORMAT " (SIGSEGV)", pc);
aoqi@0:         }
aoqi@0:         stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL);
aoqi@0:       }
aoqi@0: 
aoqi@0: #ifdef COMPILER2
aoqi@0:       // SIGTRAP-based implicit range check in compiled code.
aoqi@0:       else if (sig == SIGTRAP && TrapBasedRangeChecks &&
aoqi@0:                nativeInstruction_at(pc)->is_sigtrap_range_check()) {
aoqi@0:         if (TraceTraps) {
aoqi@0:           tty->print_cr("trap: range_check at " INTPTR_FORMAT " (SIGTRAP)", pc);
aoqi@0:         }
aoqi@0:         stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL);
aoqi@0:         goto run_stub;
aoqi@0:       }
aoqi@0: #endif
aoqi@0: 
aoqi@0:       else if (sig == SIGFPE /* && info->si_code == FPE_INTDIV */) {
aoqi@0:         if (TraceTraps) {
aoqi@0:           tty->print_raw_cr("Fix SIGFPE handler, trying divide by zero handler.");
aoqi@0:         }
aoqi@0:         stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO);
aoqi@0:         goto run_stub;
aoqi@0:       }
aoqi@0: 
aoqi@0:       else if (sig == SIGBUS) {
aoqi@0:         // BugId 4454115: A read from a MappedByteBuffer can fault here if the
aoqi@0:         // underlying file has been truncated. Do not crash the VM in such a case.
aoqi@0:         CodeBlob* cb = CodeCache::find_blob_unsafe(pc);
aoqi@0:         nmethod* nm = cb->is_nmethod() ? (nmethod*)cb : NULL;
aoqi@0:         if (nm != NULL && nm->has_unsafe_access()) {
aoqi@0:           // We don't really need a stub here! Just set the pending exeption and
aoqi@0:           // continue at the next instruction after the faulting read. Returning
aoqi@0:           // garbage from this read is ok.
aoqi@0:           thread->set_pending_unsafe_access_error();
aoqi@0:           uc->uc_mcontext.jmp_context.iar = ((unsigned long)pc) + 4;
aoqi@0:           return 1;
aoqi@0:         }
aoqi@0:       }
aoqi@0:     }
aoqi@0: 
aoqi@0:     else { // thread->thread_state() != _thread_in_Java
aoqi@0:       // Detect CPU features. This is only done at the very start of the VM. Later, the
aoqi@0:       // VM_Version::is_determine_features_test_running() flag should be false.
aoqi@0: 
aoqi@0:       if (sig == SIGILL && VM_Version::is_determine_features_test_running()) {
aoqi@0:         // SIGILL must be caused by VM_Version::determine_features().
aoqi@0:         *(int *)pc = 0; // patch instruction to 0 to indicate that it causes a SIGILL,
aoqi@0:                         // flushing of icache is not necessary.
aoqi@0:         stub = pc + 4;  // continue with next instruction.
aoqi@0:         goto run_stub;
aoqi@0:       }
aoqi@0:       else if (thread->thread_state() == _thread_in_vm &&
aoqi@0:                sig == SIGBUS && thread->doing_unsafe_access()) {
aoqi@0:         // We don't really need a stub here! Just set the pending exeption and
aoqi@0:         // continue at the next instruction after the faulting read. Returning
aoqi@0:         // garbage from this read is ok.
aoqi@0:         thread->set_pending_unsafe_access_error();
aoqi@0:         uc->uc_mcontext.jmp_context.iar = ((unsigned long)pc) + 4;
aoqi@0:         return 1;
aoqi@0:       }
aoqi@0:     }
aoqi@0: 
aoqi@0:     // Check to see if we caught the safepoint code in the
aoqi@0:     // process of write protecting the memory serialization page.
aoqi@0:     // It write enables the page immediately after protecting it
aoqi@0:     // so we can just return to retry the write.
aoqi@0:     if ((sig == SIGSEGV) &&
aoqi@0:         os::is_memory_serialize_page(thread, addr)) {
aoqi@0:       // Synchronization problem in the pseudo memory barrier code (bug id 6546278)
aoqi@0:       // Block current thread until the memory serialize page permission restored.
aoqi@0:       os::block_on_serialize_page_trap();
aoqi@0:       return true;
aoqi@0:     }
aoqi@0:   }
aoqi@0: 
aoqi@0: run_stub:
aoqi@0: 
aoqi@0:   // One of the above code blocks ininitalized the stub, so we want to
aoqi@0:   // delegate control to that stub.
aoqi@0:   if (stub != NULL) {
aoqi@0:     // Save all thread context in case we need to restore it.
aoqi@0:     if (thread != NULL) thread->set_saved_exception_pc(pc);
aoqi@0:     uc->uc_mcontext.jmp_context.iar = (unsigned long)stub;
aoqi@0:     return 1;
aoqi@0:   }
aoqi@0: 
aoqi@0: run_chained_handler:
aoqi@0: 
aoqi@0:   // signal-chaining
aoqi@0:   if (os::Aix::chained_handler(sig, info, ucVoid)) {
aoqi@0:     return 1;
aoqi@0:   }
aoqi@0:   if (!abort_if_unrecognized) {
aoqi@0:     // caller wants another chance, so give it to him
aoqi@0:     return 0;
aoqi@0:   }
aoqi@0: 
aoqi@0: report_and_die:
aoqi@0: 
aoqi@0:   // Use sigthreadmask instead of sigprocmask on AIX and unmask current signal.
aoqi@0:   sigset_t newset;
aoqi@0:   sigemptyset(&newset);
aoqi@0:   sigaddset(&newset, sig);
aoqi@0:   sigthreadmask(SIG_UNBLOCK, &newset, NULL);
aoqi@0: 
aoqi@0:   VMError err(t, sig, pc, info, ucVoid);
aoqi@0:   err.report_and_die();
aoqi@0: 
aoqi@0:   ShouldNotReachHere();
aoqi@0:   return 0;
aoqi@0: }
aoqi@0: 
aoqi@0: void os::Aix::init_thread_fpu_state(void) {
aoqi@0: #if !defined(USE_XLC_BUILTINS)
aoqi@0:   // Disable FP exceptions.
aoqi@0:   __asm__ __volatile__ ("mtfsfi 6,0");
aoqi@0: #else
aoqi@0:   __mtfsfi(6, 0);
aoqi@0: #endif
aoqi@0: }
aoqi@0: 
aoqi@0: ////////////////////////////////////////////////////////////////////////////////
aoqi@0: // thread stack
aoqi@0: 
aoqi@0: size_t os::Aix::min_stack_allowed = 768*K;
aoqi@0: 
aoqi@0: // Aix is always in floating stack mode. The stack size for a new
aoqi@0: // thread can be set via pthread_attr_setstacksize().
aoqi@0: bool os::Aix::supports_variable_stack_size() { return true; }
aoqi@0: 
aoqi@0: // return default stack size for thr_type
aoqi@0: size_t os::Aix::default_stack_size(os::ThreadType thr_type) {
aoqi@0:   // default stack size (compiler thread needs larger stack)
aoqi@0:   // Notice that the setting for compiler threads here have no impact
aoqi@0:   // because of the strange 'fallback logic' in os::create_thread().
aoqi@0:   // Better set CompilerThreadStackSize in globals_<os_cpu>.hpp if you want to
aoqi@0:   // specify a different stack size for compiler threads!
aoqi@0:   size_t s = (thr_type == os::compiler_thread ? 4 * M : 1024 * K);
aoqi@0:   return s;
aoqi@0: }
aoqi@0: 
aoqi@0: size_t os::Aix::default_guard_size(os::ThreadType thr_type) {
aoqi@0:   return 2 * page_size();
aoqi@0: }
aoqi@0: 
aoqi@0: /////////////////////////////////////////////////////////////////////////////
aoqi@0: // helper functions for fatal error handler
aoqi@0: 
aoqi@0: void os::print_context(outputStream *st, void *context) {
aoqi@0:   if (context == NULL) return;
aoqi@0: 
aoqi@0:   ucontext_t* uc = (ucontext_t*)context;
aoqi@0: 
aoqi@0:   st->print_cr("Registers:");
aoqi@0:   st->print("pc =" INTPTR_FORMAT "  ", uc->uc_mcontext.jmp_context.iar);
aoqi@0:   st->print("lr =" INTPTR_FORMAT "  ", uc->uc_mcontext.jmp_context.lr);
aoqi@0:   st->print("ctr=" INTPTR_FORMAT "  ", uc->uc_mcontext.jmp_context.ctr);
aoqi@0:   st->cr();
aoqi@0:   for (int i = 0; i < 32; i++) {
aoqi@0:     st->print("r%-2d=" INTPTR_FORMAT "  ", i, uc->uc_mcontext.jmp_context.gpr[i]);
aoqi@0:     if (i % 3 == 2) st->cr();
aoqi@0:   }
aoqi@0:   st->cr();
aoqi@0:   st->cr();
aoqi@0: 
aoqi@0:   intptr_t *sp = (intptr_t *)os::Aix::ucontext_get_sp(uc);
aoqi@0:   st->print_cr("Top of Stack: (sp=" PTR_FORMAT ")", sp);
aoqi@0:   print_hex_dump(st, (address)sp, (address)(sp + 128), sizeof(intptr_t));
aoqi@0:   st->cr();
aoqi@0: 
aoqi@0:   // Note: it may be unsafe to inspect memory near pc. For example, pc may
aoqi@0:   // point to garbage if entry point in an nmethod is corrupted. Leave
aoqi@0:   // this at the end, and hope for the best.
aoqi@0:   address pc = os::Aix::ucontext_get_pc(uc);
aoqi@0:   st->print_cr("Instructions: (pc=" PTR_FORMAT ")", pc);
aoqi@0:   print_hex_dump(st, pc - 64, pc + 64, /*instrsize=*/4);
aoqi@0:   st->cr();
aoqi@0: 
aoqi@0:   // Try to decode the instructions.
aoqi@0:   st->print_cr("Decoded instructions: (pc=" PTR_FORMAT ")", pc);
aoqi@0:   st->print("<TODO: PPC port - print_context>");
aoqi@0:   // TODO: PPC port Disassembler::decode(pc, 16, 16, st);
aoqi@0:   st->cr();
aoqi@0: }
aoqi@0: 
aoqi@0: void os::print_register_info(outputStream *st, void *context) {
aoqi@0:   if (context == NULL) return;
aoqi@0:   st->print("Not ported - print_register_info\n");
aoqi@0: }
aoqi@0: 
aoqi@0: extern "C" {
aoqi@0:   int SpinPause() {
aoqi@0:     return 0;
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: #ifndef PRODUCT
aoqi@0: void os::verify_stack_alignment() {
aoqi@0:   assert(((intptr_t)os::current_stack_pointer() & (StackAlignmentInBytes-1)) == 0, "incorrect stack alignment");
aoqi@0: }
aoqi@0: #endif