--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/os_cpu/linux_zero/vm/os_linux_zero.cpp	Tue Oct 13 12:04:21 2009 -0700
@@ -0,0 +1,456 @@
+/*
+ * Copyright 2003-2007 Sun Microsystems, Inc.  All Rights Reserved.
+ * Copyright 2007, 2008 Red Hat, Inc.
+ * 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 "incls/_os_linux_zero.cpp.incl"
+
+address os::current_stack_pointer() {
+  address dummy = (address) &dummy;
+  return dummy;
+}
+
+frame os::get_sender_for_C_frame(frame* fr) {
+  ShouldNotCallThis();
+}
+
+frame os::current_frame() {
+  // The only thing that calls this is the stack printing code in
+  // VMError::report:
+  //   - Step 110 (printing stack bounds) uses the sp in the frame
+  //     to determine the amount of free space on the stack.  We
+  //     set the sp to a close approximation of the real value in
+  //     order to allow this step to complete.
+  //   - Step 120 (printing native stack) tries to walk the stack.
+  //     The frame we create has a NULL pc, which is ignored as an
+  //     invalid frame.
+  frame dummy = frame();
+  dummy.set_sp((intptr_t *) current_stack_pointer());
+  return dummy;
+}
+
+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).
+#ifdef SPARC
+  // On SPARC, 0 != %hi(any real address), because there is no
+  // allocation in the first 1Kb of the virtual address space.
+  return (char *) 0;
+#else
+  // This is the value for x86; works pretty well for PPC too.
+  return (char *) -1;
+#endif // SPARC
+}
+
+void os::initialize_thread() {
+  // Nothing to do.
+}
+
+address os::Linux::ucontext_get_pc(ucontext_t* uc) {
+  ShouldNotCallThis();
+}
+
+ExtendedPC os::fetch_frame_from_context(void* ucVoid,
+                                        intptr_t** ret_sp,
+                                        intptr_t** ret_fp) {
+  ShouldNotCallThis();
+}
+
+frame os::fetch_frame_from_context(void* ucVoid) {
+  ShouldNotCallThis();
+}
+
+extern "C" int
+JVM_handle_linux_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);
+
+  // Note: it's not uncommon that JNI code uses signal/sigset to
+  // install then restore certain signal handler (e.g. to temporarily
+  // block SIGPIPE, or have a SIGILL handler when detecting CPU
+  // type). When that happens, JVM_handle_linux_signal() might be
+  // invoked with junk info/ucVoid. To avoid unnecessary crash when
+  // libjsig is not preloaded, try handle signals that do not require
+  // siginfo/ucontext first.
+
+  if (sig == SIGPIPE || sig == SIGXFSZ) {
+    // allow chained handler to go first
+    if (os::Linux::chained_handler(sig, info, ucVoid)) {
+      return true;
+    } else {
+      if (PrintMiscellaneous && (WizardMode || Verbose)) {
+        char buf[64];
+        warning("Ignoring %s - see bugs 4229104 or 646499219",
+                os::exception_name(sig, buf, sizeof(buf)));
+      }
+      return true;
+    }
+  }
+
+  JavaThread* thread = NULL;
+  VMThread* vmthread = NULL;
+  if (os::Linux::signal_handlers_are_installed) {
+    if (t != NULL ){
+      if(t->is_Java_thread()) {
+        thread = (JavaThread*)t;
+      }
+      else if(t->is_VM_thread()){
+        vmthread = (VMThread *)t;
+      }
+    }
+  }
+
+  if (info != NULL && thread != NULL) {
+    // Handle ALL stack overflow variations here
+    if (sig == SIGSEGV) {
+      address addr = (address) info->si_addr;
+
+      // check if fault address is within thread stack
+      if (addr < thread->stack_base() &&
+          addr >= thread->stack_base() - thread->stack_size()) {
+        // stack overflow
+        if (thread->in_stack_yellow_zone(addr)) {
+          thread->disable_stack_yellow_zone();
+          ShouldNotCallThis();
+        }
+        else if (thread->in_stack_red_zone(addr)) {
+          thread->disable_stack_red_zone();
+          ShouldNotCallThis();
+        }
+        else {
+          // Accessing stack address below sp may cause SEGV if
+          // current thread has MAP_GROWSDOWN stack. This should
+          // only happen when current thread was created by user
+          // code with MAP_GROWSDOWN flag and then attached to VM.
+          // See notes in os_linux.cpp.
+          if (thread->osthread()->expanding_stack() == 0) {
+            thread->osthread()->set_expanding_stack();
+            if (os::Linux::manually_expand_stack(thread, addr)) {
+              thread->osthread()->clear_expanding_stack();
+              return true;
+            }
+            thread->osthread()->clear_expanding_stack();
+          }
+          else {
+            fatal("recursive segv. expanding stack.");
+          }
+        }
+      }
+    }
+
+    /*if (thread->thread_state() == _thread_in_Java) {
+      ShouldNotCallThis();
+    }
+    else*/ if (thread->thread_state() == _thread_in_vm &&
+               sig == SIGBUS && thread->doing_unsafe_access()) {
+      ShouldNotCallThis();
+    }
+
+    // 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 we can
+    // just return to retry the write.
+    if (sig == SIGSEGV &&
+        os::is_memory_serialize_page(thread, (address) info->si_addr)) {
+      // Block current thread until permission is restored.
+      os::block_on_serialize_page_trap();
+      return true;
+    }
+  }
+
+  // signal-chaining
+  if (os::Linux::chained_handler(sig, info, ucVoid)) {
+     return true;
+  }
+
+  if (!abort_if_unrecognized) {
+    // caller wants another chance, so give it to him
+    return false;
+  }
+
+#ifndef PRODUCT
+  if (sig == SIGSEGV) {
+    fatal("\n#"
+          "\n#    /--------------------\\"
+          "\n#    | segmentation fault |"
+          "\n#    \\---\\ /--------------/"
+          "\n#        /"
+          "\n#    [-]        |\\_/|    "
+          "\n#    (+)=C      |o o|__  "
+          "\n#    | |        =-*-=__\\ "
+          "\n#    OOO        c_c_(___)");
+  }
+#endif // !PRODUCT
+
+  const char *fmt = "caught unhandled signal %d";
+  char buf[64];
+
+  sprintf(buf, fmt, sig);
+  fatal(buf);
+}
+
+void os::Linux::init_thread_fpu_state(void) {
+  // Nothing to do
+}
+
+int os::Linux::get_fpu_control_word() {
+  ShouldNotCallThis();
+}
+
+void os::Linux::set_fpu_control_word(int fpu) {
+  ShouldNotCallThis();
+}
+
+bool os::is_allocatable(size_t bytes) {
+  ShouldNotCallThis();
+}
+
+///////////////////////////////////////////////////////////////////////////////
+// thread stack
+
+size_t os::Linux::min_stack_allowed = 64 * K;
+
+bool os::Linux::supports_variable_stack_size() {
+  return true;
+}
+
+size_t os::Linux::default_stack_size(os::ThreadType thr_type) {
+#ifdef _LP64
+  size_t s = (thr_type == os::compiler_thread ? 4 * M : 1 * M);
+#else
+  size_t s = (thr_type == os::compiler_thread ? 2 * M : 512 * K);
+#endif // _LP64
+  return s;
+}
+
+size_t os::Linux::default_guard_size(os::ThreadType thr_type) {
+  // Only enable glibc guard pages for non-Java threads
+  // (Java threads have HotSpot guard pages)
+  return (thr_type == java_thread ? 0 : page_size());
+}
+
+static void current_stack_region(address *bottom, size_t *size) {
+  pthread_attr_t attr;
+  int res = pthread_getattr_np(pthread_self(), &attr);
+  if (res != 0) {
+    if (res == ENOMEM) {
+      vm_exit_out_of_memory(0, "pthread_getattr_np");
+    }
+    else {
+      fatal1("pthread_getattr_np failed with errno = %d", res);
+    }
+  }
+
+  address stack_bottom;
+  size_t stack_bytes;
+  res = pthread_attr_getstack(&attr, (void **) &stack_bottom, &stack_bytes);
+  if (res != 0) {
+    fatal1("pthread_attr_getstack failed with errno = %d", res);
+  }
+  address stack_top = stack_bottom + stack_bytes;
+
+  // The block of memory returned by pthread_attr_getstack() includes
+  // guard pages where present.  We need to trim these off.
+  size_t page_bytes = os::Linux::page_size();
+  assert(((intptr_t) stack_bottom & (page_bytes - 1)) == 0, "unaligned stack");
+
+  size_t guard_bytes;
+  res = pthread_attr_getguardsize(&attr, &guard_bytes);
+  if (res != 0) {
+    fatal1("pthread_attr_getguardsize failed with errno = %d", res);
+  }
+  int guard_pages = align_size_up(guard_bytes, page_bytes) / page_bytes;
+  assert(guard_bytes == guard_pages * page_bytes, "unaligned guard");
+
+#ifdef IA64
+  // IA64 has two stacks sharing the same area of memory, a normal
+  // stack growing downwards and a register stack growing upwards.
+  // Guard pages, if present, are in the centre.  This code splits
+  // the stack in two even without guard pages, though in theory
+  // there's nothing to stop us allocating more to the normal stack
+  // or more to the register stack if one or the other were found
+  // to grow faster.
+  int total_pages = align_size_down(stack_bytes, page_bytes) / page_bytes;
+  stack_bottom += (total_pages - guard_pages) / 2 * page_bytes;
+#endif // IA64
+
+  stack_bottom += guard_bytes;
+
+  pthread_attr_destroy(&attr);
+
+  // The initial thread has a growable stack, and the size reported
+  // by pthread_attr_getstack is the maximum size it could possibly
+  // be given what currently mapped.  This can be huge, so we cap it.
+  if (os::Linux::is_initial_thread()) {
+    stack_bytes = stack_top - stack_bottom;
+
+    if (stack_bytes > JavaThread::stack_size_at_create())
+      stack_bytes = JavaThread::stack_size_at_create();
+
+    stack_bottom = stack_top - stack_bytes;
+  }
+
+  assert(os::current_stack_pointer() >= stack_bottom, "should do");
+  assert(os::current_stack_pointer() < stack_top, "should do");
+
+  *bottom = stack_bottom;
+  *size = stack_top - stack_bottom;
+}
+
+address os::current_stack_base() {
+  address bottom;
+  size_t size;
+  current_stack_region(&bottom, &size);
+  return bottom + size;
+}
+
+size_t os::current_stack_size() {
+  // stack size includes normal stack and HotSpot guard pages
+  address bottom;
+  size_t size;
+  current_stack_region(&bottom, &size);
+  return size;
+}
+
+/////////////////////////////////////////////////////////////////////////////
+// helper functions for fatal error handler
+
+void os::print_context(outputStream* st, void* context) {
+  ShouldNotCallThis();
+}
+
+/////////////////////////////////////////////////////////////////////////////
+// Stubs for things that would be in linux_zero.s if it existed.
+// You probably want to disassemble these monkeys to check they're ok.
+
+extern "C" {
+  int SpinPause() {
+  }
+
+  int SafeFetch32(int *adr, int errValue) {
+    int value = errValue;
+    value = *adr;
+    return value;
+  }
+  intptr_t SafeFetchN(intptr_t *adr, intptr_t errValue) {
+    intptr_t value = errValue;
+    value = *adr;
+    return value;
+  }
+
+  void _Copy_conjoint_jshorts_atomic(jshort* from, jshort* to, size_t count) {
+    if (from > to) {
+      jshort *end = from + count;
+      while (from < end)
+        *(to++) = *(from++);
+    }
+    else if (from < to) {
+      jshort *end = from;
+      from += count - 1;
+      to   += count - 1;
+      while (from >= end)
+        *(to--) = *(from--);
+    }
+  }
+  void _Copy_conjoint_jints_atomic(jint* from, jint* to, size_t count) {
+    if (from > to) {
+      jint *end = from + count;
+      while (from < end)
+        *(to++) = *(from++);
+    }
+    else if (from < to) {
+      jint *end = from;
+      from += count - 1;
+      to   += count - 1;
+      while (from >= end)
+        *(to--) = *(from--);
+    }
+  }
+  void _Copy_conjoint_jlongs_atomic(jlong* from, jlong* to, size_t count) {
+    if (from > to) {
+      jlong *end = from + count;
+      while (from < end)
+        os::atomic_copy64(from++, to++);
+    }
+    else if (from < to) {
+      jlong *end = from;
+      from += count - 1;
+      to   += count - 1;
+      while (from >= end)
+        os::atomic_copy64(from--, to--);
+    }
+  }
+
+  void _Copy_arrayof_conjoint_bytes(HeapWord* from,
+                                    HeapWord* to,
+                                    size_t    count) {
+    ShouldNotCallThis();
+  }
+  void _Copy_arrayof_conjoint_jshorts(HeapWord* from,
+                                      HeapWord* to,
+                                      size_t    count) {
+    ShouldNotCallThis();
+  }
+  void _Copy_arrayof_conjoint_jints(HeapWord* from,
+                                    HeapWord* to,
+                                    size_t    count) {
+    ShouldNotCallThis();
+  }
+  void _Copy_arrayof_conjoint_jlongs(HeapWord* from,
+                                     HeapWord* to,
+                                     size_t    count) {
+    ShouldNotCallThis();
+  }
+};
+
+/////////////////////////////////////////////////////////////////////////////
+// Implementations of atomic operations not supported by processors.
+//  -- http://gcc.gnu.org/onlinedocs/gcc-4.2.1/gcc/Atomic-Builtins.html
+
+#ifndef _LP64
+extern "C" {
+  long long unsigned int __sync_val_compare_and_swap_8(
+    volatile void *ptr,
+    long long unsigned int oldval,
+    long long unsigned int newval) {
+    ShouldNotCallThis();
+  }
+};
+#endif // !_LP64