1 /*
   2  * Copyright 2003 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  20  * CA 95054 USA or visit www.sun.com if you need additional information or
  21  * have any questions.
  22  *
  23  */
  24 
  25 #include "incls/_precompiled.incl"
  26 #include "incls/_assembler_linux_x86_64.cpp.incl"
  27 
  28 void MacroAssembler::int3() {
  29   call(RuntimeAddress(CAST_FROM_FN_PTR(address, os::breakpoint)));
  30 }
  31 
  32 void MacroAssembler::get_thread(Register thread) {
  33   // call pthread_getspecific
  34   // void * pthread_getspecific(pthread_key_t key);
  35    if (thread != rax) {
  36      pushq(rax);
  37    }
  38    pushq(rdi);
  39    pushq(rsi);
  40    pushq(rdx);
  41    pushq(rcx);
  42    pushq(r8);
  43    pushq(r9);
  44    pushq(r10);
  45    // XXX
  46    movq(r10, rsp);
  47    andq(rsp, -16);
  48    pushq(r10);
  49    pushq(r11);
  50 
  51    movl(rdi, ThreadLocalStorage::thread_index());
  52    call(RuntimeAddress(CAST_FROM_FN_PTR(address, pthread_getspecific)));
  53 
  54    popq(r11);
  55    popq(rsp);
  56    popq(r10);
  57    popq(r9);
  58    popq(r8);
  59    popq(rcx);
  60    popq(rdx);
  61    popq(rsi);
  62    popq(rdi);
  63    if (thread != rax) {
  64        movq(thread, rax);
  65        popq(rax);
  66    }
  67 }
  68 
  69 // NOTE: since the linux kernel resides at the low end of
  70 // user address space, no null pointer check is needed.
  71 bool MacroAssembler::needs_explicit_null_check(intptr_t offset) {
  72   if (UseCompressedOops) {
  73     uintptr_t heap_base = (uintptr_t)Universe::heap_base();
  74     if ((uintptr_t)offset >= heap_base) {
  75       offset = (intptr_t)(pointer_delta((void*)offset, (void*)heap_base, 1));
  76     }
  77   }
  78   return offset < 0 || offset >= 0x100000;
  79 }