/*

 * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.

 * Copyright 2012, 2014 SAP AG. 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/assembler.hpp"

#include "asm/macroAssembler.inline.hpp"

#include "code/vtableStubs.hpp"

#include "interp_masm_ppc_64.hpp"

#include "memory/resourceArea.hpp"

#include "oops/instanceKlass.hpp"

#include "oops/klassVtable.hpp"

#include "runtime/sharedRuntime.hpp"

#include "vmreg_ppc.inline.hpp"

#ifdef COMPILER2

#include "opto/runtime.hpp"

#endif

#define __ masm->

#ifdef PRODUCT

#define BLOCK_COMMENT(str) // nothing

#else

#define BLOCK_COMMENT(str) __ block_comment(str)

#endif

#define BIND(label) bind(label); BLOCK_COMMENT(#label ":")

#ifndef PRODUCT

extern "C" void bad_compiled_vtable_index(JavaThread* thread, oopDesc* receiver, int index);

#endif

// Used by compiler only; may use only caller saved, non-argument

// registers.

VtableStub* VtableStubs::create_vtable_stub(int vtable_index) {

  // PPC port: use fixed size.

  const int code_length = VtableStub::pd_code_size_limit(true);

  VtableStub* s = new (code_length) VtableStub(true, vtable_index);

  ResourceMark rm;

  CodeBuffer cb(s->entry_point(), code_length);

  MacroAssembler* masm = new MacroAssembler(&cb);

  address start_pc;

#ifndef PRODUCT

  if (CountCompiledCalls) {

    __ load_const(R11_scratch1, SharedRuntime::nof_megamorphic_calls_addr());

    __ lwz(R12_scratch2, 0, R11_scratch1);

    __ addi(R12_scratch2, R12_scratch2, 1);

    __ stw(R12_scratch2, 0, R11_scratch1);

  }

#endif

  assert(VtableStub::receiver_location() == R3_ARG1->as_VMReg(), "receiver expected in R3_ARG1");

  // Get receiver klass.

  const Register rcvr_klass = R11_scratch1;

  // We might implicit NULL fault here.

  address npe_addr = __ pc(); // npe = null pointer exception

  __ load_klass_with_trap_null_check(rcvr_klass, R3);

 // Set method (in case of interpreted method), and destination address.

  int entry_offset = InstanceKlass::vtable_start_offset() + vtable_index*vtableEntry::size();

#ifndef PRODUCT

  if (DebugVtables) {

    Label L;

    // Check offset vs vtable length.

    const Register vtable_len = R12_scratch2;

    __ lwz(vtable_len, InstanceKlass::vtable_length_offset()*wordSize, rcvr_klass);

    __ cmpwi(CCR0, vtable_len, vtable_index*vtableEntry::size());

    __ bge(CCR0, L);

    __ li(R12_scratch2, vtable_index);

    __ call_VM(noreg, CAST_FROM_FN_PTR(address, bad_compiled_vtable_index), R3_ARG1, R12_scratch2, false);

    __ bind(L);

  }

#endif

  int v_off = entry_offset*wordSize + vtableEntry::method_offset_in_bytes();

  __ ld(R19_method, v_off, rcvr_klass);

#ifndef PRODUCT

  if (DebugVtables) {

    Label L;

    __ cmpdi(CCR0, R19_method, 0);

    __ bne(CCR0, L);

    __ stop("Vtable entry is ZERO", 102);

    __ bind(L);

  }

#endif

  // If the vtable entry is null, the method is abstract.

  address ame_addr = __ pc(); // ame = abstract method error

  __ load_with_trap_null_check(R12_scratch2, in_bytes(Method::from_compiled_offset()), R19_method);

  __ mtctr(R12_scratch2);

  __ bctr();

  masm->flush();

  guarantee(__ pc() <= s->code_end(), "overflowed buffer");

  s->set_exception_points(npe_addr, ame_addr);

  return s;

}

VtableStub* VtableStubs::create_itable_stub(int vtable_index) {

  // PPC port: use fixed size.

  const int code_length = VtableStub::pd_code_size_limit(false);

  VtableStub* s = new (code_length) VtableStub(false, vtable_index);

  ResourceMark rm;

  CodeBuffer cb(s->entry_point(), code_length);

  MacroAssembler* masm = new MacroAssembler(&cb);

  address start_pc;

#ifndef PRODUCT

  if (CountCompiledCalls) {

    __ load_const(R11_scratch1, SharedRuntime::nof_megamorphic_calls_addr());

    __ lwz(R12_scratch2, 0, R11_scratch1);

    __ addi(R12_scratch2, R12_scratch2, 1);

    __ stw(R12_scratch2, 0, R11_scratch1);

  }

#endif

  assert(VtableStub::receiver_location() == R3_ARG1->as_VMReg(), "receiver expected in R3_ARG1");

  // Entry arguments:

  //  R19_method: Interface

  //  R3_ARG1:    Receiver

  //

  const Register rcvr_klass = R11_scratch1;

  const Register vtable_len = R12_scratch2;

  const Register itable_entry_addr = R21_tmp1;

  const Register itable_interface = R22_tmp2;

  // Get receiver klass.

  // We might implicit NULL fault here.

  address npe_addr = __ pc(); // npe = null pointer exception

  __ load_klass_with_trap_null_check(rcvr_klass, R3_ARG1);

  BLOCK_COMMENT("Load start of itable entries into itable_entry.");

  __ lwz(vtable_len, InstanceKlass::vtable_length_offset() * wordSize, rcvr_klass);

  __ slwi(vtable_len, vtable_len, exact_log2(vtableEntry::size() * wordSize));

  __ add(itable_entry_addr, vtable_len, rcvr_klass);

  // Loop over all itable entries until desired interfaceOop(Rinterface) found.

  BLOCK_COMMENT("Increment itable_entry_addr in loop.");

  const int vtable_base_offset = InstanceKlass::vtable_start_offset() * wordSize;

  __ addi(itable_entry_addr, itable_entry_addr, vtable_base_offset + itableOffsetEntry::interface_offset_in_bytes());

  const int itable_offset_search_inc = itableOffsetEntry::size() * wordSize;

  Label search;

  __ bind(search);

  __ ld(itable_interface, 0, itable_entry_addr);

  // Handle IncompatibleClassChangeError in itable stubs.

  // If the entry is NULL then we've reached the end of the table

  // without finding the expected interface, so throw an exception.

  BLOCK_COMMENT("Handle IncompatibleClassChangeError in itable stubs.");

  Label throw_icce;

  __ cmpdi(CCR1, itable_interface, 0);

  __ cmpd(CCR0, itable_interface, R19_method);

  __ addi(itable_entry_addr, itable_entry_addr, itable_offset_search_inc);

  __ beq(CCR1, throw_icce);

  __ bne(CCR0, search);

  // Entry found and itable_entry_addr points to it, get offset of vtable for interface.

  const Register vtable_offset = R12_scratch2;

  const Register itable_method = R11_scratch1;

  const int vtable_offset_offset = (itableOffsetEntry::offset_offset_in_bytes() -

                                    itableOffsetEntry::interface_offset_in_bytes()) -

                                   itable_offset_search_inc;

  __ lwz(vtable_offset, vtable_offset_offset, itable_entry_addr);

  // Compute itableMethodEntry and get method and entry point for compiler.

  const int method_offset = (itableMethodEntry::size() * wordSize * vtable_index) +

    itableMethodEntry::method_offset_in_bytes();

  __ add(itable_method, rcvr_klass, vtable_offset);

  __ ld(R19_method, method_offset, itable_method);

#ifndef PRODUCT

  if (DebugVtables) {

    Label ok;

    __ cmpd(CCR0, R19_method, 0);

    __ bne(CCR0, ok);

    __ stop("method is null", 103);

    __ bind(ok);

  }

#endif

  // If the vtable entry is null, the method is abstract.

  address ame_addr = __ pc(); // ame = abstract method error

  // Must do an explicit check if implicit checks are disabled.

  assert(!MacroAssembler::needs_explicit_null_check(in_bytes(Method::from_compiled_offset())), "sanity");

  if (!ImplicitNullChecks || !os::zero_page_read_protected()) {

    if (TrapBasedNullChecks) {

      __ trap_null_check(R19_method);

    } else {

      __ cmpdi(CCR0, R19_method, 0);

      __ beq(CCR0, throw_icce);

    }

  }

  __ ld(R12_scratch2, in_bytes(Method::from_compiled_offset()), R19_method);

  __ mtctr(R12_scratch2);

  __ bctr();

  // Handle IncompatibleClassChangeError in itable stubs.

  // More detailed error message.

  // We force resolving of the call site by jumping to the "handle

  // wrong method" stub, and so let the interpreter runtime do all the

  // dirty work.

  __ bind(throw_icce);

  __ load_const(R11_scratch1, SharedRuntime::get_handle_wrong_method_stub());

  __ mtctr(R11_scratch1);

  __ bctr();

  masm->flush();

  guarantee(__ pc() <= s->code_end(), "overflowed buffer");

  s->set_exception_points(npe_addr, ame_addr);

  return s;

}

int VtableStub::pd_code_size_limit(bool is_vtable_stub) {

  if (TraceJumps || DebugVtables || CountCompiledCalls || VerifyOops) {

    return 1000;

  } else {

    int decode_klass_size = MacroAssembler::instr_size_for_decode_klass_not_null();

    if (is_vtable_stub) {

      return 20 + decode_klass_size +  8 + 8;   // Plain + cOops + Traps + safety

    } else {

      return 96 + decode_klass_size + 12 + 8;   // Plain + cOops + Traps + safety

    }

  }

}

int VtableStub::pd_code_alignment() {

  const unsigned int icache_line_size = 32;

  return icache_line_size;

}