/*

 * Copyright (c) 2004, 2017, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 *

 */

#include "precompiled.hpp"

#include "asm/macroAssembler.hpp"

#include "memory/resourceArea.hpp"

#include "prims/jniFastGetField.hpp"

#include "prims/jvm_misc.hpp"

#include "runtime/safepoint.hpp"

#define __ masm->

#define BUFFER_SIZE 30*wordSize

// Instead of issuing lfence for LoadLoad barrier, we create data dependency

// between loads, which is more efficient than lfence.

// Common register usage:

// rax/xmm0: result

// c_rarg0:    jni env

// c_rarg1:    obj

// c_rarg2:    jfield id

static const Register robj          = r9;

static const Register rcounter      = r10;

static const Register roffset       = r11;

static const Register rcounter_addr = r11;

// Warning: do not use rip relative addressing after the first counter load

// since that may scratch r10!

address JNI_FastGetField::generate_fast_get_int_field0(BasicType type) {

  const char *name = NULL;

  switch (type) {

    case T_BOOLEAN: name = "jni_fast_GetBooleanField"; break;

    case T_BYTE:    name = "jni_fast_GetByteField";    break;

    case T_CHAR:    name = "jni_fast_GetCharField";    break;

    case T_SHORT:   name = "jni_fast_GetShortField";   break;

    case T_INT:     name = "jni_fast_GetIntField";     break;

    case T_LONG:    name = "jni_fast_GetLongField";    break;

    default:        ShouldNotReachHere();

  }

  ResourceMark rm;

  BufferBlob* blob = BufferBlob::create(name, BUFFER_SIZE);

  CodeBuffer cbuf(blob);

  MacroAssembler* masm = new MacroAssembler(&cbuf);

  address fast_entry = __ pc();

  Label slow;

  ExternalAddress counter(SafepointSynchronize::safepoint_counter_addr());

  __ mov32 (rcounter, counter);

  __ mov   (robj, c_rarg1);

  __ testb (rcounter, 1);

  __ jcc (Assembler::notZero, slow);

  if (os::is_MP()) {

    __ xorptr(robj, rcounter);

    __ xorptr(robj, rcounter);                   // obj, since

                                                // robj ^ rcounter ^ rcounter == robj

                                                // robj is data dependent on rcounter.

  }

  __ clear_jweak_tag(robj);

  __ movptr(robj, Address(robj, 0));             // *obj

  __ mov   (roffset, c_rarg2);

  __ shrptr(roffset, 2);                         // offset

  assert(count < LIST_CAPACITY, "LIST_CAPACITY too small");

  speculative_load_pclist[count] = __ pc();

  switch (type) {

    case T_BOOLEAN: __ movzbl (rax, Address(robj, roffset, Address::times_1)); break;

    case T_BYTE:    __ movsbl (rax, Address(robj, roffset, Address::times_1)); break;

    case T_CHAR:    __ movzwl (rax, Address(robj, roffset, Address::times_1)); break;

    case T_SHORT:   __ movswl (rax, Address(robj, roffset, Address::times_1)); break;

    case T_INT:     __ movl   (rax, Address(robj, roffset, Address::times_1)); break;

    case T_LONG:    __ movq   (rax, Address(robj, roffset, Address::times_1)); break;

    default:        ShouldNotReachHere();

  }

  if (os::is_MP()) {

    __ lea(rcounter_addr, counter);

    // ca is data dependent on rax.

    __ xorptr(rcounter_addr, rax);

    __ xorptr(rcounter_addr, rax);

    __ cmpl (rcounter, Address(rcounter_addr, 0));

  } else {

    __ cmp32 (rcounter, counter);

  }

  __ jcc (Assembler::notEqual, slow);

  __ ret (0);

  slowcase_entry_pclist[count++] = __ pc();

  __ bind (slow);

  address slow_case_addr = NULL;

  switch (type) {

    case T_BOOLEAN: slow_case_addr = jni_GetBooleanField_addr(); break;

    case T_BYTE:    slow_case_addr = jni_GetByteField_addr();    break;

    case T_CHAR:    slow_case_addr = jni_GetCharField_addr();    break;

    case T_SHORT:   slow_case_addr = jni_GetShortField_addr();   break;

    case T_INT:     slow_case_addr = jni_GetIntField_addr();     break;

  }

  // tail call

  __ jump (ExternalAddress(slow_case_addr));

  __ flush ();

  return fast_entry;

}

address JNI_FastGetField::generate_fast_get_boolean_field() {

  return generate_fast_get_int_field0(T_BOOLEAN);

}

address JNI_FastGetField::generate_fast_get_byte_field() {

  return generate_fast_get_int_field0(T_BYTE);

}

address JNI_FastGetField::generate_fast_get_char_field() {

  return generate_fast_get_int_field0(T_CHAR);

}

address JNI_FastGetField::generate_fast_get_short_field() {

  return generate_fast_get_int_field0(T_SHORT);

}

address JNI_FastGetField::generate_fast_get_int_field() {

  return generate_fast_get_int_field0(T_INT);

}

address JNI_FastGetField::generate_fast_get_long_field() {

  return generate_fast_get_int_field0(T_LONG);

}

address JNI_FastGetField::generate_fast_get_float_field0(BasicType type) {

  const char *name = NULL;

  switch (type) {

    case T_FLOAT:     name = "jni_fast_GetFloatField";     break;

    case T_DOUBLE:    name = "jni_fast_GetDoubleField";    break;

    default:          ShouldNotReachHere();

  }

  ResourceMark rm;

  BufferBlob* blob = BufferBlob::create(name, BUFFER_SIZE);

  CodeBuffer cbuf(blob);

  MacroAssembler* masm = new MacroAssembler(&cbuf);

  address fast_entry = __ pc();

  Label slow;

  ExternalAddress counter(SafepointSynchronize::safepoint_counter_addr());

  __ mov32 (rcounter, counter);

  __ mov   (robj, c_rarg1);

  __ testb (rcounter, 1);

  __ jcc (Assembler::notZero, slow);

  if (os::is_MP()) {

    __ xorptr(robj, rcounter);

    __ xorptr(robj, rcounter);                   // obj, since

                                                // robj ^ rcounter ^ rcounter == robj

                                                // robj is data dependent on rcounter.

  }

  __ clear_jweak_tag(robj);

  __ movptr(robj, Address(robj, 0));             // *obj

  __ mov   (roffset, c_rarg2);

  __ shrptr(roffset, 2);                         // offset

  assert(count < LIST_CAPACITY, "LIST_CAPACITY too small");

  speculative_load_pclist[count] = __ pc();

  switch (type) {

    case T_FLOAT:  __ movflt (xmm0, Address(robj, roffset, Address::times_1)); break;

    case T_DOUBLE: __ movdbl (xmm0, Address(robj, roffset, Address::times_1)); break;

    default:        ShouldNotReachHere();

  }

  if (os::is_MP()) {

    __ lea(rcounter_addr, counter);

    __ movdq (rax, xmm0);

    // counter address is data dependent on xmm0.

    __ xorptr(rcounter_addr, rax);

    __ xorptr(rcounter_addr, rax);

    __ cmpl (rcounter, Address(rcounter_addr, 0));

  } else {

    __ cmp32 (rcounter, counter);

  }

  __ jcc (Assembler::notEqual, slow);

  __ ret (0);

  slowcase_entry_pclist[count++] = __ pc();

  __ bind (slow);

  address slow_case_addr = NULL;

  switch (type) {

    case T_FLOAT:     slow_case_addr = jni_GetFloatField_addr();  break;

  }

  // tail call

  __ jump (ExternalAddress(slow_case_addr));

  __ flush ();

  return fast_entry;

}

address JNI_FastGetField::generate_fast_get_float_field() {

  return generate_fast_get_float_field0(T_FLOAT);

}

address JNI_FastGetField::generate_fast_get_double_field() {

  return generate_fast_get_float_field0(T_DOUBLE);

}