/*

 * Copyright (c) 1999, 2018, 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 "c1/c1_CodeStubs.hpp"

#include "c1/c1_FrameMap.hpp"

#include "c1/c1_LIRAssembler.hpp"

#include "c1/c1_MacroAssembler.hpp"

#include "c1/c1_Runtime1.hpp"

#include "nativeInst_x86.hpp"

#include "runtime/sharedRuntime.hpp"

#include "utilities/align.hpp"

#include "utilities/macros.hpp"

#include "vmreg_x86.inline.hpp"

#define __ ce->masm()->

float ConversionStub::float_zero = 0.0;

double ConversionStub::double_zero = 0.0;

void ConversionStub::emit_code(LIR_Assembler* ce) {

  __ bind(_entry);

  assert(bytecode() == Bytecodes::_f2i || bytecode() == Bytecodes::_d2i, "other conversions do not require stub");

  if (input()->is_single_xmm()) {

    __ comiss(input()->as_xmm_float_reg(),

              ExternalAddress((address)&float_zero));

  } else if (input()->is_double_xmm()) {

    __ comisd(input()->as_xmm_double_reg(),

              ExternalAddress((address)&double_zero));

  } else {

    LP64_ONLY(ShouldNotReachHere());

    __ push(rax);

    __ ftst();

    __ fnstsw_ax();

    __ sahf();

    __ pop(rax);

  }

  Label NaN, do_return;

  __ jccb(Assembler::parity, NaN);

  __ jccb(Assembler::below, do_return);

  // input is > 0 -> return maxInt

  // result register already contains 0x80000000, so subtracting 1 gives 0x7fffffff

  __ decrement(result()->as_register());

  __ jmpb(do_return);

  // input is NaN -> return 0

  __ bind(NaN);

  __ xorptr(result()->as_register(), result()->as_register());

  __ bind(do_return);

  __ jmp(_continuation);

}

void CounterOverflowStub::emit_code(LIR_Assembler* ce) {

  __ bind(_entry);

  Metadata *m = _method->as_constant_ptr()->as_metadata();

  ce->store_parameter(m, 1);

  ce->store_parameter(_bci, 0);

  __ call(RuntimeAddress(Runtime1::entry_for(Runtime1::counter_overflow_id)));

  ce->add_call_info_here(_info);

  ce->verify_oop_map(_info);

  __ jmp(_continuation);

}

RangeCheckStub::RangeCheckStub(CodeEmitInfo* info, LIR_Opr index, LIR_Opr array)

  assert(info != NULL, "must have info");

  _info = new CodeEmitInfo(info);

}

RangeCheckStub::RangeCheckStub(CodeEmitInfo* info, LIR_Opr index)

  assert(info != NULL, "must have info");

  _info = new CodeEmitInfo(info);

}

void RangeCheckStub::emit_code(LIR_Assembler* ce) {

  __ bind(_entry);

  if (_info->deoptimize_on_exception()) {

    address a = Runtime1::entry_for(Runtime1::predicate_failed_trap_id);

    __ call(RuntimeAddress(a));

    ce->add_call_info_here(_info);

    ce->verify_oop_map(_info);

    debug_only(__ should_not_reach_here());

    return;

  }

  // pass the array index on stack because all registers must be preserved

  if (_index->is_cpu_register()) {

    ce->store_parameter(_index->as_register(), 0);

  } else {

    ce->store_parameter(_index->as_jint(), 0);

  }

  Runtime1::StubID stub_id;

  if (_throw_index_out_of_bounds_exception) {

    stub_id = Runtime1::throw_index_exception_id;

  } else {

    stub_id = Runtime1::throw_range_check_failed_id;

    ce->store_parameter(_array->as_pointer_register(), 1);

  }

  __ call(RuntimeAddress(Runtime1::entry_for(stub_id)));

  ce->add_call_info_here(_info);

  ce->verify_oop_map(_info);

  debug_only(__ should_not_reach_here());

}

PredicateFailedStub::PredicateFailedStub(CodeEmitInfo* info) {

  _info = new CodeEmitInfo(info);

}

void PredicateFailedStub::emit_code(LIR_Assembler* ce) {

  __ bind(_entry);

  address a = Runtime1::entry_for(Runtime1::predicate_failed_trap_id);

  __ call(RuntimeAddress(a));

  ce->add_call_info_here(_info);

  ce->verify_oop_map(_info);

  debug_only(__ should_not_reach_here());

}

void DivByZeroStub::emit_code(LIR_Assembler* ce) {

  if (_offset != -1) {

    ce->compilation()->implicit_exception_table()->append(_offset, __ offset());

  }

  __ bind(_entry);

  __ call(RuntimeAddress(Runtime1::entry_for(Runtime1::throw_div0_exception_id)));

  ce->add_call_info_here(_info);

  debug_only(__ should_not_reach_here());

}

// Implementation of NewInstanceStub

NewInstanceStub::NewInstanceStub(LIR_Opr klass_reg, LIR_Opr result, ciInstanceKlass* klass, CodeEmitInfo* info, Runtime1::StubID stub_id) {

  _result = result;

  _klass = klass;

  _klass_reg = klass_reg;

  _info = new CodeEmitInfo(info);

  assert(stub_id == Runtime1::new_instance_id                 ||

         stub_id == Runtime1::fast_new_instance_id            ||

         stub_id == Runtime1::fast_new_instance_init_check_id,

         "need new_instance id");

  _stub_id   = stub_id;

}

void NewInstanceStub::emit_code(LIR_Assembler* ce) {

  assert(__ rsp_offset() == 0, "frame size should be fixed");

  __ bind(_entry);

  __ movptr(rdx, _klass_reg->as_register());

  __ call(RuntimeAddress(Runtime1::entry_for(_stub_id)));

  ce->add_call_info_here(_info);

  ce->verify_oop_map(_info);

  assert(_result->as_register() == rax, "result must in rax,");

  __ jmp(_continuation);

}

// Implementation of NewTypeArrayStub

NewTypeArrayStub::NewTypeArrayStub(LIR_Opr klass_reg, LIR_Opr length, LIR_Opr result, CodeEmitInfo* info) {

  _klass_reg = klass_reg;

  _length = length;

  _result = result;

  _info = new CodeEmitInfo(info);

}

void NewTypeArrayStub::emit_code(LIR_Assembler* ce) {

  assert(__ rsp_offset() == 0, "frame size should be fixed");

  __ bind(_entry);

  assert(_length->as_register() == rbx, "length must in rbx,");

  assert(_klass_reg->as_register() == rdx, "klass_reg must in rdx");

  __ call(RuntimeAddress(Runtime1::entry_for(Runtime1::new_type_array_id)));

  ce->add_call_info_here(_info);

  ce->verify_oop_map(_info);

  assert(_result->as_register() == rax, "result must in rax,");

  __ jmp(_continuation);

}

// Implementation of NewObjectArrayStub

NewObjectArrayStub::NewObjectArrayStub(LIR_Opr klass_reg, LIR_Opr length, LIR_Opr result, CodeEmitInfo* info) {

  _klass_reg = klass_reg;

  _result = result;

  _length = length;

  _info = new CodeEmitInfo(info);

}

void NewObjectArrayStub::emit_code(LIR_Assembler* ce) {

  assert(__ rsp_offset() == 0, "frame size should be fixed");

  __ bind(_entry);

  assert(_length->as_register() == rbx, "length must in rbx,");

  assert(_klass_reg->as_register() == rdx, "klass_reg must in rdx");

  __ call(RuntimeAddress(Runtime1::entry_for(Runtime1::new_object_array_id)));

  ce->add_call_info_here(_info);

  ce->verify_oop_map(_info);

  assert(_result->as_register() == rax, "result must in rax,");

  __ jmp(_continuation);

}

// Implementation of MonitorAccessStubs

MonitorEnterStub::MonitorEnterStub(LIR_Opr obj_reg, LIR_Opr lock_reg, CodeEmitInfo* info)

: MonitorAccessStub(obj_reg, lock_reg)

{

  _info = new CodeEmitInfo(info);

}

void MonitorEnterStub::emit_code(LIR_Assembler* ce) {

  assert(__ rsp_offset() == 0, "frame size should be fixed");

  __ bind(_entry);

  ce->store_parameter(_obj_reg->as_register(),  1);

  ce->store_parameter(_lock_reg->as_register(), 0);

  Runtime1::StubID enter_id;

  if (ce->compilation()->has_fpu_code()) {

    enter_id = Runtime1::monitorenter_id;

  } else {

    enter_id = Runtime1::monitorenter_nofpu_id;

  }

  __ call(RuntimeAddress(Runtime1::entry_for(enter_id)));

  ce->add_call_info_here(_info);

  ce->verify_oop_map(_info);

  __ jmp(_continuation);

}

void MonitorExitStub::emit_code(LIR_Assembler* ce) {

  __ bind(_entry);

  if (_compute_lock) {

    // lock_reg was destroyed by fast unlocking attempt => recompute it

    ce->monitor_address(_monitor_ix, _lock_reg);

  }

  ce->store_parameter(_lock_reg->as_register(), 0);

  // note: non-blocking leaf routine => no call info needed

  Runtime1::StubID exit_id;

  if (ce->compilation()->has_fpu_code()) {

    exit_id = Runtime1::monitorexit_id;

  } else {

    exit_id = Runtime1::monitorexit_nofpu_id;

  }

  __ call(RuntimeAddress(Runtime1::entry_for(exit_id)));

  __ jmp(_continuation);

}

// Implementation of patching:

// - Copy the code at given offset to an inlined buffer (first the bytes, then the number of bytes)

// - Replace original code with a call to the stub

// At Runtime:

// - call to stub, jump to runtime

// - in runtime: preserve all registers (rspecially objects, i.e., source and destination object)

// - in runtime: after initializing class, restore original code, reexecute instruction

int PatchingStub::_patch_info_offset = -NativeGeneralJump::instruction_size;

void PatchingStub::align_patch_site(MacroAssembler* masm) {

  // We're patching a 5-7 byte instruction on intel and we need to

  // make sure that we don't see a piece of the instruction.  It

  // appears mostly impossible on Intel to simply invalidate other

  // processors caches and since they may do aggressive prefetch it's

  // very hard to make a guess about what code might be in the icache.

  // Force the instruction to be double word aligned so that it

  // doesn't span a cache line.

  masm->align(align_up((int)NativeGeneralJump::instruction_size, wordSize));

}

void PatchingStub::emit_code(LIR_Assembler* ce) {

  assert(NativeCall::instruction_size <= _bytes_to_copy && _bytes_to_copy <= 0xFF, "not enough room for call");

  Label call_patch;

  // static field accesses have special semantics while the class

  // initializer is being run so we emit a test which can be used to

  // check that this code is being executed by the initializing

  // thread.

  address being_initialized_entry = __ pc();

  if (CommentedAssembly) {

    __ block_comment(" patch template");

  }

  if (_id == load_klass_id) {

    // produce a copy of the load klass instruction for use by the being initialized case

#ifdef ASSERT

    address start = __ pc();

#endif

    Metadata* o = NULL;

    __ mov_metadata(_obj, o);

#ifdef ASSERT

    for (int i = 0; i < _bytes_to_copy; i++) {

      address ptr = (address)(_pc_start + i);

      int a_byte = (*ptr) & 0xFF;

      assert(a_byte == *start++, "should be the same code");

    }

#endif

  } else if (_id == load_mirror_id) {

    // produce a copy of the load mirror instruction for use by the being

    // initialized case

#ifdef ASSERT

    address start = __ pc();

#endif

    jobject o = NULL;

    __ movoop(_obj, o);

#ifdef ASSERT

    for (int i = 0; i < _bytes_to_copy; i++) {

      address ptr = (address)(_pc_start + i);

      int a_byte = (*ptr) & 0xFF;

      assert(a_byte == *start++, "should be the same code");

    }

#endif

  } else {

    // make a copy the code which is going to be patched.

    for (int i = 0; i < _bytes_to_copy; i++) {

      address ptr = (address)(_pc_start + i);

      int a_byte = (*ptr) & 0xFF;

      __ emit_int8(a_byte);

      *ptr = 0x90; // make the site look like a nop

    }

  }

  address end_of_patch = __ pc();

  int bytes_to_skip = 0;

  if (_id == load_mirror_id) {

    int offset = __ offset();

    if (CommentedAssembly) {

      __ block_comment(" being_initialized check");

    }

    assert(_obj != noreg, "must be a valid register");

    Register tmp = rax;

    Register tmp2 = rbx;

    __ push(tmp);

    __ push(tmp2);

    // Load without verification to keep code size small. We need it because

    // begin_initialized_entry_offset has to fit in a byte. Also, we know it's not null.

    __ movptr(tmp2, Address(_obj, java_lang_Class::klass_offset_in_bytes()));

    __ get_thread(tmp);

    __ cmpptr(tmp, Address(tmp2, InstanceKlass::init_thread_offset()));

    __ pop(tmp2);

    __ pop(tmp);

    __ jcc(Assembler::notEqual, call_patch);

    // access_field patches may execute the patched code before it's

    // copied back into place so we need to jump back into the main

    // code of the nmethod to continue execution.

    __ jmp(_patch_site_continuation);

    // make sure this extra code gets skipped

    bytes_to_skip += __ offset() - offset;

  }

  if (CommentedAssembly) {

    __ block_comment("patch data encoded as movl");

  }

  // Now emit the patch record telling the runtime how to find the

  // pieces of the patch.  We only need 3 bytes but for readability of

  // the disassembly we make the data look like a movl reg, imm32,

  // which requires 5 bytes

  int sizeof_patch_record = 5;

  bytes_to_skip += sizeof_patch_record;

  // emit the offsets needed to find the code to patch

  int being_initialized_entry_offset = __ pc() - being_initialized_entry + sizeof_patch_record;

  __ emit_int8((unsigned char)0xB8);

  __ emit_int8(0);

  __ emit_int8(being_initialized_entry_offset);

  __ emit_int8(bytes_to_skip);

  __ emit_int8(_bytes_to_copy);

  address patch_info_pc = __ pc();

  assert(patch_info_pc - end_of_patch == bytes_to_skip, "incorrect patch info");

  address entry = __ pc();

  NativeGeneralJump::insert_unconditional((address)_pc_start, entry);

  address target = NULL;

  relocInfo::relocType reloc_type = relocInfo::none;

  switch (_id) {

    case access_field_id:  target = Runtime1::entry_for(Runtime1::access_field_patching_id); break;

    case load_klass_id:    target = Runtime1::entry_for(Runtime1::load_klass_patching_id); reloc_type = relocInfo::metadata_type; break;

    case load_mirror_id:   target = Runtime1::entry_for(Runtime1::load_mirror_patching_id); reloc_type = relocInfo::oop_type; break;

    case load_appendix_id:      target = Runtime1::entry_for(Runtime1::load_appendix_patching_id); reloc_type = relocInfo::oop_type; break;

    default: ShouldNotReachHere();

  }

  __ bind(call_patch);

  if (CommentedAssembly) {

    __ block_comment("patch entry point");

  }

  __ call(RuntimeAddress(target));

  assert(_patch_info_offset == (patch_info_pc - __ pc()), "must not change");

  ce->add_call_info_here(_info);

  int jmp_off = __ offset();

  __ jmp(_patch_site_entry);

  // Add enough nops so deoptimization can overwrite the jmp above with a call

  // and not destroy the world. We cannot use fat nops here, since the concurrent

  // code rewrite may transiently create the illegal instruction sequence.

  for (int j = __ offset() ; j < jmp_off + 5 ; j++ ) {

    __ nop();

  }

  if (_id == load_klass_id || _id == load_mirror_id || _id == load_appendix_id) {

    CodeSection* cs = __ code_section();

    RelocIterator iter(cs, (address)_pc_start, (address)(_pc_start + 1));

    relocInfo::change_reloc_info_for_address(&iter, (address) _pc_start, reloc_type, relocInfo::none);

  }

}

void DeoptimizeStub::emit_code(LIR_Assembler* ce) {

  __ bind(_entry);

  ce->store_parameter(_trap_request, 0);

  __ call(RuntimeAddress(Runtime1::entry_for(Runtime1::deoptimize_id)));

  ce->add_call_info_here(_info);

  DEBUG_ONLY(__ should_not_reach_here());

}

void ImplicitNullCheckStub::emit_code(LIR_Assembler* ce) {

  address a;

  if (_info->deoptimize_on_exception()) {

    // Deoptimize, do not throw the exception, because it is probably wrong to do it here.

    a = Runtime1::entry_for(Runtime1::predicate_failed_trap_id);

  } else {

    a = Runtime1::entry_for(Runtime1::throw_null_pointer_exception_id);

  }

  ce->compilation()->implicit_exception_table()->append(_offset, __ offset());

  __ bind(_entry);

  __ call(RuntimeAddress(a));

  ce->add_call_info_here(_info);

  ce->verify_oop_map(_info);

  debug_only(__ should_not_reach_here());

}

void SimpleExceptionStub::emit_code(LIR_Assembler* ce) {

  assert(__ rsp_offset() == 0, "frame size should be fixed");

  __ bind(_entry);

  // pass the object on stack because all registers must be preserved

  if (_obj->is_cpu_register()) {

    ce->store_parameter(_obj->as_register(), 0);

  }

  __ call(RuntimeAddress(Runtime1::entry_for(_stub)));

  ce->add_call_info_here(_info);

  debug_only(__ should_not_reach_here());

}

void ArrayCopyStub::emit_code(LIR_Assembler* ce) {

  //---------------slow case: call to native-----------------

  __ bind(_entry);

  // Figure out where the args should go

  // This should really convert the IntrinsicID to the Method* and signature

  // but I don't know how to do that.

  //

  VMRegPair args[5];

  BasicType signature[5] = { T_OBJECT, T_INT, T_OBJECT, T_INT, T_INT};

  SharedRuntime::java_calling_convention(signature, args, 5, true);

  // push parameters

  // (src, src_pos, dest, destPos, length)

  Register r[5];

  r[0] = src()->as_register();

  r[1] = src_pos()->as_register();

  r[2] = dst()->as_register();

  r[3] = dst_pos()->as_register();

  r[4] = length()->as_register();

  // next registers will get stored on the stack

  for (int i = 0; i < 5 ; i++ ) {

    VMReg r_1 = args[i].first();

    if (r_1->is_stack()) {

      int st_off = r_1->reg2stack() * wordSize;

      __ movptr (Address(rsp, st_off), r[i]);

    } else {

      assert(r[i] == args[i].first()->as_Register(), "Wrong register for arg ");

    }

  }

  ce->align_call(lir_static_call);

  ce->emit_static_call_stub();

  if (ce->compilation()->bailed_out()) {

    return; // CodeCache is full

  }

  AddressLiteral resolve(SharedRuntime::get_resolve_static_call_stub(),

                         relocInfo::static_call_type);

  __ call(resolve);

  ce->add_call_info_here(info());