/*

 * Copyright (c) 2016, Oracle and/or its affiliates. All rights reserved.

 * Copyright (c) 2016 SAP SE. 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.inline.hpp"

#include "code/compiledIC.hpp"

#include "code/icBuffer.hpp"

#include "code/nmethod.hpp"

#include "memory/resourceArea.hpp"

#include "runtime/mutexLocker.hpp"

#include "runtime/safepoint.hpp"

#ifdef COMPILER2

#include "opto/matcher.hpp"

#endif

// ----------------------------------------------------------------------------

#undef  __

#define __ _masm.

address CompiledStaticCall::emit_to_interp_stub(CodeBuffer &cbuf, address mark/* = NULL*/) {

#ifdef COMPILER2

  // Stub is fixed up when the corresponding call is converted from calling

  // compiled code to calling interpreted code.

  if (mark == NULL) {

    // Get the mark within main instrs section which is set to the address of the call.

    mark = cbuf.insts_mark();

  }

  assert(mark != NULL, "mark must not be NULL");

  // Note that the code buffer's insts_mark is always relative to insts.

  // That's why we must use the macroassembler to generate a stub.

  MacroAssembler _masm(&cbuf);

  address stub = __ start_a_stub(Compile::MAX_stubs_size);

  if (stub == NULL) {

    return NULL;  // CodeBuffer::expand failed.

  }

  __ relocate(static_stub_Relocation::spec(mark));

  AddressLiteral meta = __ allocate_metadata_address(NULL);

  bool success = __ load_const_from_toc(as_Register(Matcher::inline_cache_reg_encode()), meta);

  __ set_inst_mark();

  AddressLiteral a((address)-1);

  success = success && __ load_const_from_toc(Z_R1, a);

  if (!success) {

    return NULL;  // CodeCache is full.

  }

  __ z_br(Z_R1);

  __ end_a_stub(); // Update current stubs pointer and restore insts_end.

  return stub;

#else

  ShouldNotReachHere();

#endif

}

#undef __

int CompiledStaticCall::to_interp_stub_size() {

  return 2 * MacroAssembler::load_const_from_toc_size() +

         2; // branch

}

// Relocation entries for call stub, compiled java to interpreter.

int CompiledStaticCall::reloc_to_interp_stub() {

  return 5; // 4 in emit_java_to_interp + 1 in Java_Static_Call

}

void CompiledDirectStaticCall::set_to_interpreted(const methodHandle& callee, address entry) {

  address stub = find_stub(/*is_aot*/ false);

  guarantee(stub != NULL, "stub not found");

  if (TraceICs) {

    ResourceMark rm;

    tty->print_cr("CompiledDirectStaticCall@" INTPTR_FORMAT ": set_to_interpreted %s",

                  p2i(instruction_address()),

                  callee->name_and_sig_as_C_string());

  }

  // Creation also verifies the object.

  NativeMovConstReg* method_holder = nativeMovConstReg_at(stub + NativeCall::get_IC_pos_in_java_to_interp_stub());

  NativeJump*        jump          = nativeJump_at(method_holder->next_instruction_address());

#ifdef ASSERT

  // A generated lambda form might be deleted from the Lambdaform

  // cache in MethodTypeForm.  If a jit compiled lambdaform method

  // becomes not entrant and the cache access returns null, the new

  // resolve will lead to a new generated LambdaForm.

  volatile intptr_t data = method_holder->data();

  volatile address destination = jump->jump_destination();

  assert(data == 0 || data == (intptr_t)callee() || callee->is_compiled_lambda_form(),

         "a) MT-unsafe modification of inline cache");

  assert(destination == (address)-1 || destination == entry,

         "b) MT-unsafe modification of inline cache");

#endif

  // Update stub.

  method_holder->set_data((intptr_t)callee());

  jump->set_jump_destination(entry);

  // Update jump to call.

  set_destination_mt_safe(stub);

}

void CompiledDirectStaticCall::set_stub_to_clean(static_stub_Relocation* static_stub) {

  assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "mt unsafe call");

  // Reset stub.

  address stub = static_stub->addr();

  assert(stub != NULL, "stub not found");

  // Creation also verifies the object.

  NativeMovConstReg* method_holder = nativeMovConstReg_at(stub + NativeCall::get_IC_pos_in_java_to_interp_stub());

  NativeJump*        jump          = nativeJump_at(method_holder->next_instruction_address());

  method_holder->set_data(0);

  jump->set_jump_destination((address)-1);

}

//-----------------------------------------------------------------------------

#ifndef PRODUCT

void CompiledDirectStaticCall::verify() {

  // Verify call.

  _call->verify();

  if (os::is_MP()) {

    _call->verify_alignment();

  }

  // Verify stub.

  address stub = find_stub(/*is_aot*/ false);

  assert(stub != NULL, "no stub found for static call");

  // Creation also verifies the object.

  NativeMovConstReg* method_holder = nativeMovConstReg_at(stub + NativeCall::get_IC_pos_in_java_to_interp_stub());

  NativeJump*        jump          = nativeJump_at(method_holder->next_instruction_address());

  // Verify state.

  assert(is_clean() || is_call_to_compiled() || is_call_to_interpreted(), "sanity check");

}

#endif // !PRODUCT