src/hotspot/cpu/aarch64/gc/shared/barrierSetAssembler_aarch64.cpp
author rkennke
Sun, 06 May 2018 00:42:59 +0200
changeset 50024 7238cb613dc5
parent 49929 f38329fe8055
child 50110 3d98842c8677
permissions -rw-r--r--
8202676: AArch64: Missing enter/leave around barrier leads to infinite loop Reviewed-by: aph, eosterlund

/*
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 * 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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 * questions.
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 */

#include "precompiled.hpp"
#include "gc/shared/barrierSetAssembler.hpp"
#include "runtime/jniHandles.hpp"

#define __ masm->

void BarrierSetAssembler::load_at(MacroAssembler* masm, DecoratorSet decorators, BasicType type,
                                  Register dst, Address src, Register tmp1, Register tmp_thread) {

  // LR is live.  It must be saved around calls.

  bool on_heap = (decorators & IN_HEAP) != 0;
  bool on_root = (decorators & IN_ROOT) != 0;
  switch (type) {
  case T_OBJECT:
  case T_ARRAY: {
    if (on_heap) {
      __ load_heap_oop(dst, src);
    } else {
      assert(on_root, "why else?");
      __ ldr(dst, src);
    }
    break;
  }
  default: Unimplemented();
  }
}

void BarrierSetAssembler::store_at(MacroAssembler* masm, DecoratorSet decorators, BasicType type,
                                   Address dst, Register val, Register tmp1, Register tmp2) {
  bool on_heap = (decorators & IN_HEAP) != 0;
  bool on_root = (decorators & IN_ROOT) != 0;
  switch (type) {
  case T_OBJECT:
  case T_ARRAY: {
    if (on_heap) {
      __ store_heap_oop(dst, val);
    } else {
      assert(on_root, "why else?");
      __ str(val, dst);
    }
    break;
  }
  default: Unimplemented();
  }
}

void BarrierSetAssembler::try_resolve_jobject_in_native(MacroAssembler* masm, Register jni_env,
                                                        Register obj, Register tmp, Label& slowpath) {
  // If mask changes we need to ensure that the inverse is still encodable as an immediate
  STATIC_ASSERT(JNIHandles::weak_tag_mask == 1);
  __ andr(obj, obj, ~JNIHandles::weak_tag_mask);
  __ ldr(obj, Address(obj, 0));             // *obj
}