/*

 * Copyright (c) 2013, 2015, 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 "compiler/disassembler.hpp"

#include "oops/oop.inline.hpp"

#include "runtime/javaCalls.hpp"

#include "runtime/sharedRuntime.hpp"

#include "jvmci/jvmciEnv.hpp"

#include "jvmci/jvmciCodeInstaller.hpp"

#include "jvmci/jvmciJavaClasses.hpp"

#include "jvmci/jvmciCompilerToVM.hpp"

#include "jvmci/jvmciRuntime.hpp"

#include "asm/register.hpp"

#include "classfile/vmSymbols.hpp"

#include "code/vmreg.hpp"

#include "vmreg_x86.inline.hpp"

jint CodeInstaller::pd_next_offset(NativeInstruction* inst, jint pc_offset, oop method) {

  if (inst->is_call() || inst->is_jump()) {

    assert(NativeCall::instruction_size == (int)NativeJump::instruction_size, "unexpected size");

    return (pc_offset + NativeCall::instruction_size);

  } else if (inst->is_mov_literal64()) {

    // mov+call instruction pair

    jint offset = pc_offset + NativeMovConstReg::instruction_size;

    u_char* call = (u_char*) (_instructions->start() + offset);

    if (call[0] == Assembler::REX_B) {

      offset += 1; /* prefix byte for extended register R8-R15 */

      call++;

    }

    assert(call[0] == 0xFF, "expected call");

    offset += 2; /* opcode byte + modrm byte */

    return (offset);

  } else if (inst->is_call_reg()) {

    // the inlined vtable stub contains a "call register" instruction

    assert(method != NULL, "only valid for virtual calls");

    return (pc_offset + ((NativeCallReg *) inst)->next_instruction_offset());

  } else if (inst->is_cond_jump()) {

    address pc = (address) (inst);

    return pc_offset + (jint) (Assembler::locate_next_instruction(pc) - pc);

  } else {

    fatal("unsupported type of instruction for call site");

    return 0;

  }

}

void CodeInstaller::pd_patch_OopConstant(int pc_offset, Handle& constant) {

  address pc = _instructions->start() + pc_offset;

  Handle obj = HotSpotObjectConstantImpl::object(constant);

  jobject value = JNIHandles::make_local(obj());

  if (HotSpotObjectConstantImpl::compressed(constant)) {

#ifdef _LP64

    address operand = Assembler::locate_operand(pc, Assembler::narrow_oop_operand);

    int oop_index = _oop_recorder->find_index(value);

    _instructions->relocate(pc, oop_Relocation::spec(oop_index), Assembler::narrow_oop_operand);

    TRACE_jvmci_3("relocating (narrow oop constant) at " PTR_FORMAT "/" PTR_FORMAT, p2i(pc), p2i(operand));

#else

    fatal("compressed oop on 32bit");

#endif

  } else {

    address operand = Assembler::locate_operand(pc, Assembler::imm_operand);

    *((jobject*) operand) = value;

    _instructions->relocate(pc, oop_Relocation::spec_for_immediate(), Assembler::imm_operand);

    TRACE_jvmci_3("relocating (oop constant) at " PTR_FORMAT "/" PTR_FORMAT, p2i(pc), p2i(operand));

  }

}

void CodeInstaller::pd_patch_DataSectionReference(int pc_offset, int data_offset) {

  address pc = _instructions->start() + pc_offset;

  address operand = Assembler::locate_operand(pc, Assembler::disp32_operand);

  address next_instruction = Assembler::locate_next_instruction(pc);

  address dest = _constants->start() + data_offset;

  long disp = dest - next_instruction;

  assert(disp == (jint) disp, "disp doesn't fit in 32 bits");

  *((jint*) operand) = (jint) disp;

  _instructions->relocate(pc, section_word_Relocation::spec((address) dest, CodeBuffer::SECT_CONSTS), Assembler::disp32_operand);

  TRACE_jvmci_3("relocating at " PTR_FORMAT "/" PTR_FORMAT " with destination at " PTR_FORMAT " (%d)", p2i(pc), p2i(operand), p2i(dest), data_offset);

}

void CodeInstaller::pd_relocate_CodeBlob(CodeBlob* cb, NativeInstruction* inst) {

  if (cb->is_nmethod()) {

    nmethod* nm = (nmethod*) cb;

    nativeJump_at((address)inst)->set_jump_destination(nm->verified_entry_point());

  } else {

    nativeJump_at((address)inst)->set_jump_destination(cb->code_begin());

  }

  _instructions->relocate((address)inst, runtime_call_Relocation::spec(), Assembler::call32_operand);

}

void CodeInstaller::pd_relocate_ForeignCall(NativeInstruction* inst, jlong foreign_call_destination) {

  address pc = (address) inst;

  if (inst->is_call()) {

    // NOTE: for call without a mov, the offset must fit a 32-bit immediate

    //       see also CompilerToVM.getMaxCallTargetOffset()

    NativeCall* call = nativeCall_at(pc);

    call->set_destination((address) foreign_call_destination);

    _instructions->relocate(call->instruction_address(), runtime_call_Relocation::spec(), Assembler::call32_operand);

  } else if (inst->is_mov_literal64()) {

    NativeMovConstReg* mov = nativeMovConstReg_at(pc);

    mov->set_data((intptr_t) foreign_call_destination);

    _instructions->relocate(mov->instruction_address(), runtime_call_Relocation::spec(), Assembler::imm_operand);

  } else if (inst->is_jump()) {

    NativeJump* jump = nativeJump_at(pc);

    jump->set_jump_destination((address) foreign_call_destination);

    _instructions->relocate(jump->instruction_address(), runtime_call_Relocation::spec(), Assembler::call32_operand);

  } else if (inst->is_cond_jump()) {

    address old_dest = nativeGeneralJump_at(pc)->jump_destination();

    address disp = Assembler::locate_operand(pc, Assembler::call32_operand);

    *(jint*) disp += ((address) foreign_call_destination) - old_dest;

    _instructions->relocate(pc, runtime_call_Relocation::spec(), Assembler::call32_operand);

  } else {

    fatal("unsupported relocation for foreign call");

  }

  TRACE_jvmci_3("relocating (foreign call)  at " PTR_FORMAT, p2i(inst));

}

void CodeInstaller::pd_relocate_JavaMethod(oop hotspot_method, jint pc_offset) {

#ifdef ASSERT

  Method* method = NULL;

  // we need to check, this might also be an unresolved method

  if (hotspot_method->is_a(HotSpotResolvedJavaMethodImpl::klass())) {

    method = getMethodFromHotSpotMethod(hotspot_method);

  }

#endif

  switch (_next_call_type) {

    case INLINE_INVOKE:

      break;

    case INVOKEVIRTUAL:

    case INVOKEINTERFACE: {

      assert(method == NULL || !method->is_static(), "cannot call static method with invokeinterface");

      NativeCall* call = nativeCall_at(_instructions->start() + pc_offset);

      call->set_destination(SharedRuntime::get_resolve_virtual_call_stub());

      _instructions->relocate(call->instruction_address(),

                                             virtual_call_Relocation::spec(_invoke_mark_pc),

                                             Assembler::call32_operand);

      break;

    }

    case INVOKESTATIC: {

      assert(method == NULL || method->is_static(), "cannot call non-static method with invokestatic");

      NativeCall* call = nativeCall_at(_instructions->start() + pc_offset);

      call->set_destination(SharedRuntime::get_resolve_static_call_stub());

      _instructions->relocate(call->instruction_address(),

                                             relocInfo::static_call_type, Assembler::call32_operand);

      break;

    }

    case INVOKESPECIAL: {

      assert(method == NULL || !method->is_static(), "cannot call static method with invokespecial");

      NativeCall* call = nativeCall_at(_instructions->start() + pc_offset);

      call->set_destination(SharedRuntime::get_resolve_opt_virtual_call_stub());

      _instructions->relocate(call->instruction_address(),

                              relocInfo::opt_virtual_call_type, Assembler::call32_operand);

      break;

    }

    default:

      break;

  }

}

static void relocate_poll_near(address pc) {

  NativeInstruction* ni = nativeInstruction_at(pc);

  int32_t* disp = (int32_t*) Assembler::locate_operand(pc, Assembler::disp32_operand);

  int32_t offset = *disp; // The Java code installed the polling page offset into the disp32 operand

  intptr_t new_disp = (intptr_t) (os::get_polling_page() + offset) - (intptr_t) ni;

  *disp = (int32_t)new_disp;

}

void CodeInstaller::pd_relocate_poll(address pc, jint mark) {

  switch (mark) {

    case POLL_NEAR: {

      relocate_poll_near(pc);

      _instructions->relocate(pc, relocInfo::poll_type, Assembler::disp32_operand);

      break;

    }

    case POLL_FAR:

      // This is a load from a register so there is no relocatable operand.

      // We just have to ensure that the format is not disp32_operand

      // so that poll_Relocation::fix_relocation_after_move does the right

      // thing (i.e. ignores this relocation record)

      _instructions->relocate(pc, relocInfo::poll_type, Assembler::imm_operand);

      break;

    case POLL_RETURN_NEAR: {

      relocate_poll_near(pc);

      _instructions->relocate(pc, relocInfo::poll_return_type, Assembler::disp32_operand);

      break;

    }

    case POLL_RETURN_FAR:

      // see comment above for POLL_FAR

      _instructions->relocate(pc, relocInfo::poll_return_type, Assembler::imm_operand);

      break;

    default:

      fatal("invalid mark value");

      break;

  }

}

// convert JVMCI register indices (as used in oop maps) to HotSpot registers

VMReg CodeInstaller::get_hotspot_reg(jint jvmci_reg) {

  if (jvmci_reg < RegisterImpl::number_of_registers) {

    return as_Register(jvmci_reg)->as_VMReg();

  } else {

    jint floatRegisterNumber = jvmci_reg - RegisterImpl::number_of_registers;

    if (floatRegisterNumber < XMMRegisterImpl::number_of_registers) {

      return as_XMMRegister(floatRegisterNumber)->as_VMReg();

    }

    ShouldNotReachHere();

    return NULL;

  }

}

bool CodeInstaller::is_general_purpose_reg(VMReg hotspotRegister) {

  return !(hotspotRegister->is_FloatRegister() || hotspotRegister->is_XMMRegister());

}