/*

 * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.

 * Copyright (c) 2014, Red Hat Inc. 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 "assembler_aarch64.inline.hpp"

#include "code/vtableStubs.hpp"

#include "interp_masm_aarch64.hpp"

#include "memory/resourceArea.hpp"

#include "oops/instanceKlass.hpp"

#include "oops/klassVtable.hpp"

#include "runtime/sharedRuntime.hpp"

#include "vmreg_aarch64.inline.hpp"

#ifdef COMPILER2

#include "opto/runtime.hpp"

#endif

// machine-dependent part of VtableStubs: create VtableStub of correct size and

// initialize its code

#define __ masm->

#ifndef PRODUCT

extern "C" void bad_compiled_vtable_index(JavaThread* thread,

                                          oop receiver,

                                          int index);

#endif

VtableStub* VtableStubs::create_vtable_stub(int vtable_index) {

  const int aarch64_code_length = VtableStub::pd_code_size_limit(true);

  VtableStub* s = new(aarch64_code_length) VtableStub(true, vtable_index);

  ResourceMark rm;

  CodeBuffer cb(s->entry_point(), aarch64_code_length);

  MacroAssembler* masm = new MacroAssembler(&cb);

#ifndef PRODUCT

  if (CountCompiledCalls) {

    __ lea(r19, ExternalAddress((address) SharedRuntime::nof_megamorphic_calls_addr()));

    __ incrementw(Address(r19));

  }

#endif

  // get receiver (need to skip return address on top of stack)

  assert(VtableStub::receiver_location() == j_rarg0->as_VMReg(), "receiver expected in j_rarg0");

  // get receiver klass

  address npe_addr = __ pc();

  __ load_klass(r19, j_rarg0);

#ifndef PRODUCT

  if (DebugVtables) {

    Label L;

    // check offset vs vtable length

    __ ldrw(rscratch1, Address(r19, InstanceKlass::vtable_length_offset() * wordSize));

    __ cmpw(rscratch1, vtable_index * vtableEntry::size());

    __ br(Assembler::GT, L);

    __ enter();

    __ mov(r2, vtable_index);

    __ call_VM(noreg,

               CAST_FROM_FN_PTR(address, bad_compiled_vtable_index), j_rarg0, r2);

    __ leave();

    __ bind(L);

  }

#endif // PRODUCT

  __ lookup_virtual_method(r19, vtable_index, rmethod);

  if (DebugVtables) {

    Label L;

    __ cbz(rmethod, L);

    __ ldr(rscratch1, Address(rmethod, Method::from_compiled_offset()));

    __ cbnz(rscratch1, L);

    __ stop("Vtable entry is NULL");

    __ bind(L);

  }

  // r0: receiver klass

  // rmethod: Method*

  // r2: receiver

  address ame_addr = __ pc();

  __ ldr(rscratch1, Address(rmethod, Method::from_compiled_offset()));

  __ br(rscratch1);

  __ flush();

  if (PrintMiscellaneous && (WizardMode || Verbose)) {

    tty->print_cr("vtable #%d at "PTR_FORMAT"[%d] left over: %d",

                  vtable_index, p2i(s->entry_point()),

                  (int)(s->code_end() - s->entry_point()),

                  (int)(s->code_end() - __ pc()));

  }

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

  s->set_exception_points(npe_addr, ame_addr);

  return s;

}

VtableStub* VtableStubs::create_itable_stub(int itable_index) {

  // Note well: pd_code_size_limit is the absolute minimum we can get

  // away with.  If you add code here, bump the code stub size

  // returned by pd_code_size_limit!

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

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

  ResourceMark rm;

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

  MacroAssembler* masm = new MacroAssembler(&cb);

#ifndef PRODUCT

  if (CountCompiledCalls) {

    __ lea(r10, ExternalAddress((address) SharedRuntime::nof_megamorphic_calls_addr()));

    __ incrementw(Address(r10));

  }

#endif

  // Entry arguments:

  //  rscratch2: Interface

  //  j_rarg0: Receiver

  // Free registers (non-args) are r0 (interface), rmethod

  // get receiver (need to skip return address on top of stack)

  assert(VtableStub::receiver_location() == j_rarg0->as_VMReg(), "receiver expected in j_rarg0");

  // get receiver klass (also an implicit null-check)

  address npe_addr = __ pc();

  // Most registers are in use; we'll use r0, rmethod, r10, r11

  __ load_klass(r10, j_rarg0);

  Label throw_icce;

  // Get Method* and entrypoint for compiler

  __ lookup_interface_method(// inputs: rec. class, interface, itable index

                             r10, rscratch2, itable_index,

                             // outputs: method, scan temp. reg

                             rmethod, r11,

                             throw_icce);

  // method (rmethod): Method*

  // j_rarg0: receiver

#ifdef ASSERT

  if (DebugVtables) {

    Label L2;

    __ cbz(rmethod, L2);

    __ ldr(rscratch1, Address(rmethod, Method::from_compiled_offset()));

    __ cbnz(rscratch1, L2);

    __ stop("compiler entrypoint is null");

    __ bind(L2);

  }

#endif // ASSERT

  // rmethod: Method*

  // j_rarg0: receiver

  address ame_addr = __ pc();

  __ ldr(rscratch1, Address(rmethod, Method::from_compiled_offset()));

  __ br(rscratch1);

  __ bind(throw_icce);

  __ far_jump(RuntimeAddress(StubRoutines::throw_IncompatibleClassChangeError_entry()));

  __ flush();

  if (PrintMiscellaneous && (WizardMode || Verbose)) {

    tty->print_cr("itable #%d at "PTR_FORMAT"[%d] left over: %d",

                  itable_index, p2i(s->entry_point()),

                  (int)(s->code_end() - s->entry_point()),

                  (int)(s->code_end() - __ pc()));

  }

  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) {

  int size = DebugVtables ? 216 : 0;

  if (CountCompiledCalls)

    size += 6 * 4;

  // FIXME

  if (is_vtable_stub)

    size += 52;

  else

    size += 104;

  return size;

  // In order to tune these parameters, run the JVM with VM options

  // +PrintMiscellaneous and +WizardMode to see information about

  // actual itable stubs.  Run it with -Xmx31G -XX:+UseCompressedOops.

  //

  // If Universe::narrow_klass_base is nonzero, decoding a compressed

  // class can take zeveral instructions.  Run it with -Xmx31G

  // -XX:+UseCompressedOops.

  //

  // The JVM98 app. _202_jess has a megamorphic interface call.

  // The itable code looks like this:

  // Decoding VtableStub itbl[1]@12

  //     ldr     w10, [x1,#8]

  //     lsl     x10, x10, #3

  //     ldr     w11, [x10,#280]

  //     add     x11, x10, x11, uxtx #3

  //     add     x11, x11, #0x1b8

  //     ldr     x12, [x11]

  //     cmp     x9, x12

  //     b.eq    success

  // loop:

  //     cbz     x12, throw_icce

  //     add     x11, x11, #0x10

  //     ldr     x12, [x11]

  //     cmp     x9, x12

  //     b.ne    loop

  // success:

  //     ldr     x11, [x11,#8]

  //     ldr     x12, [x10,x11]

  //     ldr     x8, [x12,#72]

  //     br      x8

  // throw_icce:

  //     b      throw_ICCE_entry

}

int VtableStub::pd_code_alignment() { return 4; }