android-4.0.1_r1/s

// Copyright 2011 the V8 project authors. All rights reserved.
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
//     * Redistributions of source code must retain the above copyright
//       notice, this list of conditions and the following disclaimer.
//     * Redistributions in binary form must reproduce the above
//       copyright notice, this list of conditions and the following
//       disclaimer in the documentation and/or other materials provided
//       with the distribution.
//     * Neither the name of Google Inc. nor the names of its
//       contributors may be used to endorse or promote products derived
//       from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

#include "v8.h"

#if defined(V8_TARGET_ARCH_X64)

#include "codegen.h"
#include "ic-inl.h"
#include "runtime.h"
#include "stub-cache.h"

namespace v8 {
namespace internal {

// ----------------------------------------------------------------------------
// Static IC stub generators.
//

#define __ ACCESS_MASM(masm)


static void GenerateGlobalInstanceTypeCheck(MacroAssembler* masm,
                                            Register type,
                                            Label* global_object) {
  // Register usage:
  //   type: holds the receiver instance type on entry.
  __ cmpb(type, Immediate(JS_GLOBAL_OBJECT_TYPE));
  __ j(equal, global_object);
  __ cmpb(type, Immediate(JS_BUILTINS_OBJECT_TYPE));
  __ j(equal, global_object);
  __ cmpb(type, Immediate(JS_GLOBAL_PROXY_TYPE));
  __ j(equal, global_object);
}


// Generated code falls through if the receiver is a regular non-global
// JS object with slow properties and no interceptors.
static void GenerateStringDictionaryReceiverCheck(MacroAssembler* masm,
                                                  Register receiver,
                                                  Register r0,
                                                  Register r1,
                                                  Label* miss) {
  // Register usage:
  //   receiver: holds the receiver on entry and is unchanged.
  //   r0: used to hold receiver instance type.
  //       Holds the property dictionary on fall through.
  //   r1: used to hold receivers map.

  __ JumpIfSmi(receiver, miss);

  // Check that the receiver is a valid JS object.
  __ movq(r1, FieldOperand(receiver, HeapObject::kMapOffset));
  __ movb(r0, FieldOperand(r1, Map::kInstanceTypeOffset));
  __ cmpb(r0, Immediate(FIRST_JS_OBJECT_TYPE));
  __ j(below, miss);

  // If this assert fails, we have to check upper bound too.
  ASSERT(LAST_TYPE == JS_FUNCTION_TYPE);

  GenerateGlobalInstanceTypeCheck(masm, r0, miss);

  // Check for non-global object that requires access check.
  __ testb(FieldOperand(r1, Map::kBitFieldOffset),
           Immediate((1 << Map::kIsAccessCheckNeeded) |
                     (1 << Map::kHasNamedInterceptor)));
  __ j(not_zero, miss);

  __ movq(r0, FieldOperand(receiver, JSObject::kPropertiesOffset));
  __ CompareRoot(FieldOperand(r0, HeapObject::kMapOffset),
                 Heap::kHashTableMapRootIndex);
  __ j(not_equal, miss);
}


// Probe the string dictionary in the |elements| register. Jump to the
// |done| label if a property with the given name is found leaving the
// index into the dictionary in |r1|. Jump to the |miss| label
// otherwise.
static void GenerateStringDictionaryProbes(MacroAssembler* masm,
                                           Label* miss,
                                           Label* done,
                                           Register elements,
                                           Register name,
                                           Register r0,
                                           Register r1) {
  // Assert that name contains a string.
  if (FLAG_debug_code) __ AbortIfNotString(name);

  // Compute the capacity mask.
  const int kCapacityOffset =
      StringDictionary::kHeaderSize +
      StringDictionary::kCapacityIndex * kPointerSize;
  __ SmiToInteger32(r0, FieldOperand(elements, kCapacityOffset));
  __ decl(r0);

  // Generate an unrolled loop that performs a few probes before
  // giving up. Measurements done on Gmail indicate that 2 probes
  // cover ~93% of loads from dictionaries.
  static const int kProbes = 4;
  const int kElementsStartOffset =
      StringDictionary::kHeaderSize +
      StringDictionary::kElementsStartIndex * kPointerSize;
  for (int i = 0; i < kProbes; i++) {
    // Compute the masked index: (hash + i + i * i) & mask.
    __ movl(r1, FieldOperand(name, String::kHashFieldOffset));
    __ shrl(r1, Immediate(String::kHashShift));
    if (i > 0) {
      __ addl(r1, Immediate(StringDictionary::GetProbeOffset(i)));
    }
    __ and_(r1, r0);

    // Scale the index by multiplying by the entry size.
    ASSERT(StringDictionary::kEntrySize == 3);
    __ lea(r1, Operand(r1, r1, times_2, 0));  // r1 = r1 * 3

    // Check if the key is identical to the name.
    __ cmpq(name, Operand(elements, r1, times_pointer_size,
                          kElementsStartOffset - kHeapObjectTag));
    if (i != kProbes - 1) {
      __ j(equal, done);
    } else {
      __ j(not_equal, miss);
    }
  }
}


// Helper function used to load a property from a dictionary backing storage.
// This function may return false negatives, so miss_label
// must always call a backup property load that is complete.
// This function is safe to call if name is not a symbol, and will jump to
// the miss_label in that case.
// The generated code assumes that the receiver has slow properties,
// is not a global object and does not have interceptors.
static void GenerateDictionaryLoad(MacroAssembler* masm,
                                   Label* miss_label,
                                   Register elements,
                                   Register name,
                                   Register r0,
                                   Register r1,
                                   Register result) {
  // Register use:
  //
  // elements - holds the property dictionary on entry and is unchanged.
  //
  // name - holds the name of the property on entry and is unchanged.
  //
  // r0   - used to hold the capacity of the property dictionary.
  //
  // r1   - used to hold the index into the property dictionary.
  //
  // result - holds the result on exit if the load succeeded.

  Label done;

  // Probe the dictionary.
  GenerateStringDictionaryProbes(masm,
                                 miss_label,
                                 &done,
                                 elements,
                                 name,
                                 r0,
                                 r1);

  // If probing finds an entry in the dictionary, r0 contains the
  // index into the dictionary. Check that the value is a normal
  // property.
  __ bind(&done);
  const int kElementsStartOffset =
      StringDictionary::kHeaderSize +
      StringDictionary::kElementsStartIndex * kPointerSize;
  const int kDetailsOffset = kElementsStartOffset + 2 * kPointerSize;
  __ Test(Operand(elements, r1, times_pointer_size,
                  kDetailsOffset - kHeapObjectTag),
          Smi::FromInt(PropertyDetails::TypeField::mask()));
  __ j(not_zero, miss_label);

  // Get the value at the masked, scaled index.
  const int kValueOffset = kElementsStartOffset + kPointerSize;
  __ movq(result,
          Operand(elements, r1, times_pointer_size,
                  kValueOffset - kHeapObjectTag));
}


// Helper function used to store a property to a dictionary backing
// storage. This function may fail to store a property even though it
// is in the dictionary, so code at miss_label must always call a
// backup property store that is complete. This function is safe to
// call if name is not a symbol, and will jump to the miss_label in
// that case. The generated code assumes that the receiver has slow
// properties, is not a global object and does not have interceptors.
static void GenerateDictionaryStore(MacroAssembler* masm,
                                    Label* miss_label,
                                    Register elements,
                                    Register name,
                                    Register value,
                                    Register scratch0,
                                    Register scratch1) {
  // Register use:
  //
  // elements - holds the property dictionary on entry and is clobbered.
  //
  // name - holds the name of the property on entry and is unchanged.
  //
  // value - holds the value to store and is unchanged.
  //
  // scratch0 - used for index into the property dictionary and is clobbered.
  //
  // scratch1 - used to hold the capacity of the property dictionary and is
  //            clobbered.
  Label done;

  // Probe the dictionary.
  GenerateStringDictionaryProbes(masm,
                                 miss_label,
                                 &done,
                                 elements,
                                 name,
                                 scratch0,
                                 scratch1);

  // If probing finds an entry in the dictionary, scratch0 contains the
  // index into the dictionary. Check that the value is a normal
  // property that is not read only.
  __ bind(&done);
  const int kElementsStartOffset =
      StringDictionary::kHeaderSize +
      StringDictionary::kElementsStartIndex * kPointerSize;
  const int kDetailsOffset = kElementsStartOffset + 2 * kPointerSize;
  const int kTypeAndReadOnlyMask
      = (PropertyDetails::TypeField::mask() |
         PropertyDetails::AttributesField::encode(READ_ONLY)) << kSmiTagSize;
  __ Test(Operand(elements,
                  scratch1,
                  times_pointer_size,
                  kDetailsOffset - kHeapObjectTag),
          Smi::FromInt(kTypeAndReadOnlyMask));
  __ j(not_zero, miss_label);

  // Store the value at the masked, scaled index.
  const int kValueOffset = kElementsStartOffset + kPointerSize;
  __ lea(scratch1, Operand(elements,
                           scratch1,
                           times_pointer_size,
                           kValueOffset - kHeapObjectTag));
  __ movq(Operand(scratch1, 0), value);

  // Update write barrier. Make sure not to clobber the value.
  __ movq(scratch0, value);
  __ RecordWrite(elements, scratch1, scratch0);
}


static void GenerateNumberDictionaryLoad(MacroAssembler* masm,
                                         Label* miss,
                                         Register elements,
                                         Register key,
                                         Register r0,
                                         Register r1,
                                         Register r2,
                                         Register result) {
  // Register use:
  //
  // elements - holds the slow-case elements of the receiver on entry.
  //            Unchanged unless 'result' is the same register.
  //
  // key      - holds the smi key on entry.
  //            Unchanged unless 'result' is the same register.
  //
  // Scratch registers:
  //
  // r0 - holds the untagged key on entry and holds the hash once computed.
  //
  // r1 - used to hold the capacity mask of the dictionary
  //
  // r2 - used for the index into the dictionary.
  //
  // result - holds the result on exit if the load succeeded.
  //          Allowed to be the same as 'key' or 'result'.
  //          Unchanged on bailout so 'key' or 'result' can be used
  //          in further computation.

  Label done;

  // Compute the hash code from the untagged key.  This must be kept in sync
  // with ComputeIntegerHash in utils.h.
  //
  // hash = ~hash + (hash << 15);
  __ movl(r1, r0);
  __ notl(r0);
  __ shll(r1, Immediate(15));
  __ addl(r0, r1);
  // hash = hash ^ (hash >> 12);
  __ movl(r1, r0);
  __ shrl(r1, Immediate(12));
  __ xorl(r0, r1);
  // hash = hash + (hash << 2);
  __ leal(r0, Operand(r0, r0, times_4, 0));
  // hash = hash ^ (hash >> 4);
  __ movl(r1, r0);
  __ shrl(r1, Immediate(4));
  __ xorl(r0, r1);
  // hash = hash * 2057;
  __ imull(r0, r0, Immediate(2057));
  // hash = hash ^ (hash >> 16);
  __ movl(r1, r0);
  __ shrl(r1, Immediate(16));
  __ xorl(r0, r1);

  // Compute capacity mask.
  __ SmiToInteger32(r1,
                    FieldOperand(elements, NumberDictionary::kCapacityOffset));
  __ decl(r1);

  // Generate an unrolled loop that performs a few probes before giving up.
  const int kProbes = 4;
  for (int i = 0; i < kProbes; i++) {
    // Use r2 for index calculations and keep the hash intact in r0.
    __ movq(r2, r0);
    // Compute the masked index: (hash + i + i * i) & mask.
    if (i > 0) {
      __ addl(r2, Immediate(NumberDictionary::GetProbeOffset(i)));
    }
    __ and_(r2, r1);

    // Scale the index by multiplying by the entry size.
    ASSERT(NumberDictionary::kEntrySize == 3);
    __ lea(r2, Operand(r2, r2, times_2, 0));  // r2 = r2 * 3

    // Check if the key matches.
    __ cmpq(key, FieldOperand(elements,
                              r2,
                              times_pointer_size,
                              NumberDictionary::kElementsStartOffset));
    if (i != (kProbes - 1)) {
      __ j(equal, &done);
    } else {
      __ j(not_equal, miss);
    }
  }

  __ bind(&done);
  // Check that the value is a normal propety.
  const int kDetailsOffset =
      NumberDictionary::kElementsStartOffset + 2 * kPointerSize;
  ASSERT_EQ(NORMAL, 0);
  __ Test(FieldOperand(elements, r2, times_pointer_size, kDetailsOffset),
          Smi::FromInt(PropertyDetails::TypeField::mask()));
  __ j(not_zero, miss);

  // Get the value at the masked, scaled index.
  const int kValueOffset =
      NumberDictionary::kElementsStartOffset + kPointerSize;
  __ movq(result, FieldOperand(elements, r2, times_pointer_size, kValueOffset));
}


// The offset from the inlined patch site to the start of the inlined
// load instruction.
const int LoadIC::kOffsetToLoadInstruction = 20;


void LoadIC::GenerateArrayLength(MacroAssembler* masm) {
  // ----------- S t a t e -------------
  //  -- rax    : receiver
  //  -- rcx    : name
  //  -- rsp[0] : return address
  // -----------------------------------
  Label miss;

  StubCompiler::GenerateLoadArrayLength(masm, rax, rdx, &miss);
  __ bind(&miss);
  StubCompiler::GenerateLoadMiss(masm, Code::LOAD_IC);
}


void LoadIC::GenerateStringLength(MacroAssembler* masm, bool support_wrappers) {
  // ----------- S t a t e -------------
  //  -- rax    : receiver
  //  -- rcx    : name
  //  -- rsp[0] : return address
  // -----------------------------------
  Label miss;

  StubCompiler::GenerateLoadStringLength(masm, rax, rdx, rbx, &miss,
                                         support_wrappers);
  __ bind(&miss);
  StubCompiler::GenerateLoadMiss(masm, Code::LOAD_IC);
}


void LoadIC::GenerateFunctionPrototype(MacroAssembler* masm) {
  // ----------- S t a t e -------------
  //  -- rax    : receiver
  //  -- rcx    : name
  //  -- rsp[0] : return address
  // -----------------------------------
  Label miss;

  StubCompiler::GenerateLoadFunctionPrototype(masm, rax, rdx, rbx, &miss);
  __ bind(&miss);
  StubCompiler::GenerateLoadMiss(masm, Code::LOAD_IC);
}


// Checks the receiver for special cases (value type, slow case bits).
// Falls through for regular JS object.
static void GenerateKeyedLoadReceiverCheck(MacroAssembler* masm,
                                           Register receiver,
                                           Register map,
                                           int interceptor_bit,
                                           Label* slow) {
  // Register use:
  //   receiver - holds the receiver and is unchanged.
  // Scratch registers:
  //   map - used to hold the map of the receiver.

  // Check that the object isn't a smi.
  __ JumpIfSmi(receiver, slow);

  // Check that the object is some kind of JS object EXCEPT JS Value type.
  // In the case that the object is a value-wrapper object,
  // we enter the runtime system to make sure that indexing
  // into string objects work as intended.
  ASSERT(JS_OBJECT_TYPE > JS_VALUE_TYPE);
  __ CmpObjectType(receiver, JS_OBJECT_TYPE, map);
  __ j(below, slow);

  // Check bit field.
  __ testb(FieldOperand(map, Map::kBitFieldOffset),
           Immediate((1 << Map::kIsAccessCheckNeeded) |
                     (1 << interceptor_bit)));
  __ j(not_zero, slow);
}


// Loads an indexed element from a fast case array.
// If not_fast_array is NULL, doesn't perform the elements map check.
static void GenerateFastArrayLoad(MacroAssembler* masm,
                                  Register receiver,
                                  Register key,
                                  Register elements,
                                  Register scratch,
                                  Register result,
                                  Label* not_fast_array,
                                  Label* out_of_range) {
  // Register use:
  //
  // receiver - holds the receiver on entry.
  //            Unchanged unless 'result' is the same register.
  //
  // key      - holds the smi key on entry.
  //            Unchanged unless 'result' is the same register.
  //
  // elements - holds the elements of the receiver on exit.
  //
  // result   - holds the result on exit if the load succeeded.
  //            Allowed to be the the same as 'receiver' or 'key'.
  //            Unchanged on bailout so 'receiver' and 'key' can be safely
  //            used by further computation.
  //
  // Scratch registers:
  //
  //   scratch - used to hold elements of the receiver and the loaded value.

  __ movq(elements, FieldOperand(receiver, JSObject::kElementsOffset));
  if (not_fast_array != NULL) {
    // Check that the object is in fast mode and writable.
    __ CompareRoot(FieldOperand(elements, HeapObject::kMapOffset),
                   Heap::kFixedArrayMapRootIndex);
    __ j(not_equal, not_fast_array);
  } else {
    __ AssertFastElements(elements);
  }
  // Check that the key (index) is within bounds.
  __ SmiCompare(key, FieldOperand(elements, FixedArray::kLengthOffset));
  // Unsigned comparison rejects negative indices.
  __ j(above_equal, out_of_range);
  // Fast case: Do the load.
  SmiIndex index = masm->SmiToIndex(scratch, key, kPointerSizeLog2);
  __ movq(scratch, FieldOperand(elements,
                                index.reg,
                                index.scale,
                                FixedArray::kHeaderSize));
  __ CompareRoot(scratch, Heap::kTheHoleValueRootIndex);
  // In case the loaded value is the_hole we have to consult GetProperty
  // to ensure the prototype chain is searched.
  __ j(equal, out_of_range);
  if (!result.is(scratch)) {
    __ movq(result, scratch);
  }
}


// Checks whether a key is an array index string or a symbol string.
// Falls through if the key is a symbol.
static void GenerateKeyStringCheck(MacroAssembler* masm,
                                   Register key,
                                   Register map,
                                   Register hash,
                                   Label* index_string,
                                   Label* not_symbol) {
  // Register use:
  //   key - holds the key and is unchanged. Assumed to be non-smi.
  // Scratch registers:
  //   map - used to hold the map of the key.
  //   hash - used to hold the hash of the key.
  __ CmpObjectType(key, FIRST_NONSTRING_TYPE, map);
  __ j(above_equal, not_symbol);
  // Is the string an array index, with cached numeric value?
  __ movl(hash, FieldOperand(key, String::kHashFieldOffset));
  __ testl(hash, Immediate(String::kContainsCachedArrayIndexMask));
  __ j(zero, index_string);  // The value in hash is used at jump target.

  // Is the string a symbol?
  ASSERT(kSymbolTag != 0);
  __ testb(FieldOperand(map, Map::kInstanceTypeOffset),
           Immediate(kIsSymbolMask));
  __ j(zero, not_symbol);
}


void KeyedLoadIC::GenerateGeneric(MacroAssembler* masm) {
  // ----------- S t a t e -------------
  //  -- rax    : key
  //  -- rdx    : receiver
  //  -- rsp[0] : return address
  // -----------------------------------
  Label slow, check_string, index_smi, index_string, property_array_property;
  Label probe_dictionary, check_number_dictionary;

  // Check that the key is a smi.
  __ JumpIfNotSmi(rax, &check_string);
  __ bind(&index_smi);
  // Now the key is known to be a smi. This place is also jumped to from below
  // where a numeric string is converted to a smi.

  GenerateKeyedLoadReceiverCheck(
      masm, rdx, rcx, Map::kHasIndexedInterceptor, &slow);

  // Check the "has fast elements" bit in the receiver's map which is
  // now in rcx.
  __ testb(FieldOperand(rcx, Map::kBitField2Offset),
           Immediate(1 << Map::kHasFastElements));
  __ j(zero, &check_number_dictionary);

  GenerateFastArrayLoad(masm,
                        rdx,
                        rax,
                        rcx,
                        rbx,
                        rax,
                        NULL,
                        &slow);
  Counters* counters = masm->isolate()->counters();
  __ IncrementCounter(counters->keyed_load_generic_smi(), 1);
  __ ret(0);

  __ bind(&check_number_dictionary);
  __ SmiToInteger32(rbx, rax);
  __ movq(rcx, FieldOperand(rdx, JSObject::kElementsOffset));

  // Check whether the elements is a number dictionary.
  // rdx: receiver
  // rax: key
  // rbx: key as untagged int32
  // rcx: elements
  __ CompareRoot(FieldOperand(rcx, HeapObject::kMapOffset),
                 Heap::kHashTableMapRootIndex);
  __ j(not_equal, &slow);
  GenerateNumberDictionaryLoad(masm, &slow, rcx, rax, rbx, r9, rdi, rax);
  __ ret(0);

  __ bind(&slow);
  // Slow case: Jump to runtime.
  // rdx: receiver
  // rax: key
  __ IncrementCounter(counters->keyed_load_generic_slow(), 1);
  GenerateRuntimeGetProperty(masm);

  __ bind(&check_string);
  GenerateKeyStringCheck(masm, rax, rcx, rbx, &index_string, &slow);

  GenerateKeyedLoadReceiverCheck(
      masm, rdx, rcx, Map::kHasNamedInterceptor, &slow);

  // If the receiver is a fast-case object, check the keyed lookup
  // cache. Otherwise probe the dictionary leaving result in rcx.
  __ movq(rbx, FieldOperand(rdx, JSObject::kPropertiesOffset));
  __ CompareRoot(FieldOperand(rbx, HeapObject::kMapOffset),
                 Heap::kHashTableMapRootIndex);
  __ j(equal, &probe_dictionary);

  // Load the map of the receiver, compute the keyed lookup cache hash
  // based on 32 bits of the map pointer and the string hash.
  __ movq(rbx, FieldOperand(rdx, HeapObject::kMapOffset));
  __ movl(rcx, rbx);
  __ shr(rcx, Immediate(KeyedLookupCache::kMapHashShift));
  __ movl(rdi, FieldOperand(rax, String::kHashFieldOffset));
  __ shr(rdi, Immediate(String::kHashShift));
  __ xor_(rcx, rdi);
  __ and_(rcx, Immediate(KeyedLookupCache::kCapacityMask));

  // Load the key (consisting of map and symbol) from the cache and
  // check for match.
  ExternalReference cache_keys
      = ExternalReference::keyed_lookup_cache_keys(masm->isolate());
  __ movq(rdi, rcx);
  __ shl(rdi, Immediate(kPointerSizeLog2 + 1));
  __ LoadAddress(kScratchRegister, cache_keys);
  __ cmpq(rbx, Operand(kScratchRegister, rdi, times_1, 0));
  __ j(not_equal, &slow);
  __ cmpq(rax, Operand(kScratchRegister, rdi, times_1, kPointerSize));
  __ j(not_equal, &slow);

  // Get field offset, which is a 32-bit integer.
  ExternalReference cache_field_offsets
      = ExternalReference::keyed_lookup_cache_field_offsets(masm->isolate());
  __ LoadAddress(kScratchRegister, cache_field_offsets);
  __ movl(rdi, Operand(kScratchRegister, rcx, times_4, 0));
  __ movzxbq(rcx, FieldOperand(rbx, Map::kInObjectPropertiesOffset));
  __ subq(rdi, rcx);
  __ j(above_equal, &property_array_property);

  // Load in-object property.
  __ movzxbq(rcx, FieldOperand(rbx, Map::kInstanceSizeOffset));
  __ addq(rcx, rdi);
  __ movq(rax, FieldOperand(rdx, rcx, times_pointer_size, 0));
  __ IncrementCounter(counters->keyed_load_generic_lookup_cache(), 1);
  __ ret(0);

  // Load property array property.
  __ bind(&property_array_property);
  __ movq(rax, FieldOperand(rdx, JSObject::kPropertiesOffset));
  __ movq(rax, FieldOperand(rax, rdi, times_pointer_size,
                            FixedArray::kHeaderSize));
  __ IncrementCounter(counters->keyed_load_generic_lookup_cache(), 1);
  __ ret(0);

  // Do a quick inline probe of the receiver's dictionary, if it
  // exists.
  __ bind(&probe_dictionary);
  // rdx: receiver
  // rax: key
  // rbx: elements

  __ movq(rcx, FieldOperand(rdx, JSObject::kMapOffset));
  __ movb(rcx, FieldOperand(rcx, Map::kInstanceTypeOffset));
  GenerateGlobalInstanceTypeCheck(masm, rcx, &slow);

  GenerateDictionaryLoad(masm, &slow, rbx, rax, rcx, rdi, rax);
  __ IncrementCounter(counters->keyed_load_generic_symbol(), 1);
  __ ret(0);

  __ bind(&index_string);
  __ IndexFromHash(rbx, rax);
  __ jmp(&index_smi);
}


void KeyedLoadIC::GenerateString(MacroAssembler* masm) {
  // ----------- S t a t e -------------
  //  -- rax    : key
  //  -- rdx    : receiver
  //  -- rsp[0] : return address
  // -----------------------------------
  Label miss;

  Register receiver = rdx;
  Register index = rax;
  Register scratch1 = rbx;
  Register scratch2 = rcx;
  Register result = rax;

  StringCharAtGenerator char_at_generator(receiver,
                                          index,
                                          scratch1,
                                          scratch2,
                                          result,
                                          &miss,  // When not a string.
                                          &miss,  // When not a number.
                                          &miss,  // When index out of range.
                                          STRING_INDEX_IS_ARRAY_INDEX);
  char_at_generator.GenerateFast(masm);
  __ ret(0);

  StubRuntimeCallHelper call_helper;
  char_at_generator.GenerateSlow(masm, call_helper);

  __ bind(&miss);
  GenerateMiss(masm);
}


void KeyedLoadIC::GenerateIndexedInterceptor(MacroAssembler* masm) {
  // ----------- S t a t e -------------
  //  -- rax    : key
  //  -- rdx    : receiver
  //  -- rsp[0] : return address
  // -----------------------------------
  Label slow;

  // Check that the receiver isn't a smi.
  __ JumpIfSmi(rdx, &slow);

  // Check that the key is an array index, that is Uint32.
  STATIC_ASSERT(kSmiValueSize <= 32);
  __ JumpUnlessNonNegativeSmi(rax, &slow);

  // Get the map of the receiver.
  __ movq(rcx, FieldOperand(rdx, HeapObject::kMapOffset));

  // Check that it has indexed interceptor and access checks
  // are not enabled for this object.
  __ movb(rcx, FieldOperand(rcx, Map::kBitFieldOffset));
  __ andb(rcx, Immediate(kSlowCaseBitFieldMask));
  __ cmpb(rcx, Immediate(1 << Map::kHasIndexedInterceptor));
  __ j(not_zero, &slow);

  // Everything is fine, call runtime.
  __ pop(rcx);
  __ push(rdx);  // receiver
  __ push(rax);  // key
  __ push(rcx);  // return address

  // Perform tail call to the entry.
  __ TailCallExternalReference(
      ExternalReference(IC_Utility(kKeyedLoadPropertyWithInterceptor),
                        masm->isolate()),
      2,
      1);

  __ bind(&slow);
  GenerateMiss(masm);
}


void KeyedStoreIC::GenerateGeneric(MacroAssembler* masm,
                                   StrictModeFlag strict_mode) {
  // ----------- S t a t e -------------
  //  -- rax     : value
  //  -- rcx     : key
  //  -- rdx     : receiver
  //  -- rsp[0]  : return address
  // -----------------------------------
  Label slow, slow_with_tagged_index, fast, array, extra;

  // Check that the object isn't a smi.
  __ JumpIfSmi(rdx, &slow_with_tagged_index);
  // Get the map from the receiver.
  __ movq(rbx, FieldOperand(rdx, HeapObject::kMapOffset));
  // Check that the receiver does not require access checks.  We need
  // to do this because this generic stub does not perform map checks.
  __ testb(FieldOperand(rbx, Map::kBitFieldOffset),
           Immediate(1 << Map::kIsAccessCheckNeeded));
  __ j(not_zero, &slow_with_tagged_index);
  // Check that the key is a smi.
  __ JumpIfNotSmi(rcx, &slow_with_tagged_index);
  __ SmiToInteger32(rcx, rcx);

  __ CmpInstanceType(rbx, JS_ARRAY_TYPE);
  __ j(equal, &array);
  // Check that the object is some kind of JS object.
  __ CmpInstanceType(rbx, FIRST_JS_OBJECT_TYPE);
  __ j(below, &slow);

  // Object case: Check key against length in the elements array.
  // rax: value
  // rdx: JSObject
  // rcx: index
  __ movq(rbx, FieldOperand(rdx, JSObject::kElementsOffset));
  // Check that the object is in fast mode and writable.
  __ CompareRoot(FieldOperand(rbx, HeapObject::kMapOffset),
                 Heap::kFixedArrayMapRootIndex);
  __ j(not_equal, &slow);
  __ SmiCompareInteger32(FieldOperand(rbx, FixedArray::kLengthOffset), rcx);
  // rax: value
  // rbx: FixedArray
  // rcx: index
  __ j(above, &fast);

  // Slow case: call runtime.
  __ bind(&slow);
  __ Integer32ToSmi(rcx, rcx);
  __ bind(&slow_with_tagged_index);
  GenerateRuntimeSetProperty(masm, strict_mode);
  // Never returns to here.

  // Extra capacity case: Check if there is extra capacity to
  // perform the store and update the length. Used for adding one
  // element to the array by writing to array[array.length].
  __ bind(&extra);
  // rax: value
  // rdx: receiver (a JSArray)
  // rbx: receiver's elements array (a FixedArray)
  // rcx: index
  // flags: smicompare (rdx.length(), rbx)
  __ j(not_equal, &slow);  // do not leave holes in the array
  __ SmiCompareInteger32(FieldOperand(rbx, FixedArray::kLengthOffset), rcx);
  __ j(below_equal, &slow);
  // Increment index to get new length.
  __ leal(rdi, Operand(rcx, 1));
  __ Integer32ToSmiField(FieldOperand(rdx, JSArray::kLengthOffset), rdi);
  __ jmp(&fast);

  // Array case: Get the length and the elements array from the JS
  // array. Check that the array is in fast mode (and writable); if it
  // is the length is always a smi.
  __ bind(&array);
  // rax: value
  // rdx: receiver (a JSArray)
  // rcx: index
  __ movq(rbx, FieldOperand(rdx, JSObject::kElementsOffset));
  __ CompareRoot(FieldOperand(rbx, HeapObject::kMapOffset),
                 Heap::kFixedArrayMapRootIndex);
  __ j(not_equal, &slow);

  // Check the key against the length in the array, compute the
  // address to store into and fall through to fast case.
  __ SmiCompareInteger32(FieldOperand(rdx, JSArray::kLengthOffset), rcx);
  __ j(below_equal, &extra);

  // Fast case: Do the store.
  __ bind(&fast);
  // rax: value
  // rbx: receiver's elements array (a FixedArray)
  // rcx: index
  NearLabel non_smi_value;
  __ movq(FieldOperand(rbx, rcx, times_pointer_size, FixedArray::kHeaderSize),
          rax);
  __ JumpIfNotSmi(rax, &non_smi_value);
  __ ret(0);
  __ bind(&non_smi_value);
  // Slow case that needs to retain rcx for use by RecordWrite.
  // Update write barrier for the elements array address.
  __ movq(rdx, rax);
  __ RecordWriteNonSmi(rbx, 0, rdx, rcx);
  __ ret(0);
}


// The generated code does not accept smi keys.
// The generated code falls through if both probes miss.
static void GenerateMonomorphicCacheProbe(MacroAssembler* masm,
                                          int argc,
                                          Code::Kind kind) {
  // ----------- S t a t e -------------
  // rcx                      : function name
  // rdx                      : receiver
  // -----------------------------------
  Label number, non_number, non_string, boolean, probe, miss;

  // Probe the stub cache.
  Code::Flags flags = Code::ComputeFlags(kind,
                                         NOT_IN_LOOP,
                                         MONOMORPHIC,
                                         Code::kNoExtraICState,
                                         NORMAL,
                                         argc);
  Isolate::Current()->stub_cache()->GenerateProbe(masm, flags, rdx, rcx, rbx,
                                                  rax);

  // If the stub cache probing failed, the receiver might be a value.
  // For value objects, we use the map of the prototype objects for
  // the corresponding JSValue for the cache and that is what we need
  // to probe.
  //
  // Check for number.
  __ JumpIfSmi(rdx, &number);
  __ CmpObjectType(rdx, HEAP_NUMBER_TYPE, rbx);
  __ j(not_equal, &non_number);
  __ bind(&number);
  StubCompiler::GenerateLoadGlobalFunctionPrototype(
      masm, Context::NUMBER_FUNCTION_INDEX, rdx);
  __ jmp(&probe);

  // Check for string.
  __ bind(&non_number);
  __ CmpInstanceType(rbx, FIRST_NONSTRING_TYPE);
  __ j(above_equal, &non_string);
  StubCompiler::GenerateLoadGlobalFunctionPrototype(
      masm, Context::STRING_FUNCTION_INDEX, rdx);
  __ jmp(&probe);

  // Check for boolean.
  __ bind(&non_string);
  __ CompareRoot(rdx, Heap::kTrueValueRootIndex);
  __ j(equal, &boolean);
  __ CompareRoot(rdx, Heap::kFalseValueRootIndex);
  __ j(not_equal, &miss);
  __ bind(&boolean);
  StubCompiler::GenerateLoadGlobalFunctionPrototype(
      masm, Context::BOOLEAN_FUNCTION_INDEX, rdx);

  // Probe the stub cache for the value object.
  __ bind(&probe);
  Isolate::Current()->stub_cache()->GenerateProbe(masm, flags, rdx, rcx, rbx,
                                                  no_reg);

  __ bind(&miss);
}


static void GenerateFunctionTailCall(MacroAssembler* masm,
                                     int argc,
                                     Label* miss) {
  // ----------- S t a t e -------------
  // rcx                    : function name
  // rdi                    : function
  // rsp[0]                 : return address
  // rsp[8]                 : argument argc
  // rsp[16]                : argument argc - 1
  // ...
  // rsp[argc * 8]          : argument 1
  // rsp[(argc + 1) * 8]    : argument 0 = receiver
  // -----------------------------------
  __ JumpIfSmi(rdi, miss);
  // Check that the value is a JavaScript function.
  __ CmpObjectType(rdi, JS_FUNCTION_TYPE, rdx);
  __ j(not_equal, miss);

  // Invoke the function.
  ParameterCount actual(argc);
  __ InvokeFunction(rdi, actual, JUMP_FUNCTION);
}


// The generated code falls through if the call should be handled by runtime.
static void GenerateCallNormal(MacroAssembler* masm, int argc) {
  // ----------- S t a t e -------------
  // rcx                    : function name
  // rsp[0]                 : return address
  // rsp[8]                 : argument argc
  // rsp[16]                : argument argc - 1
  // ...
  // rsp[argc * 8]          : argument 1
  // rsp[(argc + 1) * 8]    : argument 0 = receiver
  // -----------------------------------
  Label miss;

  // Get the receiver of the function from the stack.
  __ movq(rdx, Operand(rsp, (argc + 1) * kPointerSize));

  GenerateStringDictionaryReceiverCheck(masm, rdx, rax, rbx, &miss);

  // rax: elements
  // Search the dictionary placing the result in rdi.
  GenerateDictionaryLoad(masm, &miss, rax, rcx, rbx, rdi, rdi);

  GenerateFunctionTailCall(masm, argc, &miss);

  __ bind(&miss);
}


static void GenerateCallMiss(MacroAssembler* masm, int argc, IC::UtilityId id) {
  // ----------- S t a t e -------------
  // rcx                      : function name
  // rsp[0]                   : return address
  // rsp[8]                   : argument argc
  // rsp[16]                  : argument argc - 1
  // ...
  // rsp[argc * 8]            : argument 1
  // rsp[(argc + 1) * 8]      : argument 0 = receiver
  // -----------------------------------

  Counters* counters = masm->isolate()->counters();
  if (id == IC::kCallIC_Miss) {
    __ IncrementCounter(counters->call_miss(), 1);
  } else {
    __ IncrementCounter(counters->keyed_call_miss(), 1);
  }

  // Get the receiver of the function from the stack; 1 ~ return address.
  __ movq(rdx, Operand(rsp, (argc + 1) * kPointerSize));

  // Enter an internal frame.
  __ EnterInternalFrame();

  // Push the receiver and the name of the function.
  __ push(rdx);
  __ push(rcx);

  // Call the entry.
  CEntryStub stub(1);
  __ Set(rax, 2);
  __ LoadAddress(rbx, ExternalReference(IC_Utility(id), masm->isolate()));
  __ CallStub(&stub);

  // Move result to rdi and exit the internal frame.
  __ movq(rdi, rax);
  __ LeaveInternalFrame();

  // Check if the receiver is a global object of some sort.
  // This can happen only for regular CallIC but not KeyedCallIC.
  if (id == IC::kCallIC_Miss) {
    Label invoke, global;
    __ movq(rdx, Operand(rsp, (argc + 1) * kPointerSize));  // receiver
    __ JumpIfSmi(rdx, &invoke);
    __ CmpObjectType(rdx, JS_GLOBAL_OBJECT_TYPE, rcx);
    __ j(equal, &global);
    __ CmpInstanceType(rcx, JS_BUILTINS_OBJECT_TYPE);
    __ j(not_equal, &invoke);

    // Patch the receiver on the stack.
    __ bind(&global);
    __ movq(rdx, FieldOperand(rdx, GlobalObject::kGlobalReceiverOffset));
    __ movq(Operand(rsp, (argc + 1) * kPointerSize), rdx);
    __ bind(&invoke);
  }

  // Invoke the function.
  ParameterCount actual(argc);
  __ InvokeFunction(rdi, actual, JUMP_FUNCTION);
}


void CallIC::GenerateMegamorphic(MacroAssembler* masm, int argc) {
  // ----------- S t a t e -------------
  // rcx                      : function name
  // rsp[0]                   : return address
  // rsp[8]                   : argument argc
  // rsp[16]                  : argument argc - 1
  // ...
  // rsp[argc * 8]            : argument 1
  // rsp[(argc + 1) * 8]      : argument 0 = receiver
  // -----------------------------------

  // Get the receiver of the function from the stack; 1 ~ return address.
  __ movq(rdx, Operand(rsp, (argc + 1) * kPointerSize));
  GenerateMonomorphicCacheProbe(masm, argc, Code::CALL_IC);
  GenerateMiss(masm, argc);
}


void CallIC::GenerateNormal(MacroAssembler* masm, int argc) {
  // ----------- S t a t e -------------
  // rcx                      : function name
  // rsp[0]                   : return address
  // rsp[8]                   : argument argc
  // rsp[16]                  : argument argc - 1
  // ...
  // rsp[argc * 8]            : argument 1
  // rsp[(argc + 1) * 8]      : argument 0 = receiver
  // -----------------------------------

  GenerateCallNormal(masm, argc);
  GenerateMiss(masm, argc);
}


void CallIC::GenerateMiss(MacroAssembler* masm, int argc) {
  // ----------- S t a t e -------------
  // rcx                      : function name
  // rsp[0]                   : return address
  // rsp[8]                   : argument argc
  // rsp[16]                  : argument argc - 1
  // ...
  // rsp[argc * 8]            : argument 1
  // rsp[(argc + 1) * 8]      : argument 0 = receiver
  // -----------------------------------

  GenerateCallMiss(masm, argc, IC::kCallIC_Miss);
}


void KeyedCallIC::GenerateMegamorphic(MacroAssembler* masm, int argc) {
  // ----------- S t a t e -------------
  // rcx                      : function name
  // rsp[0]                   : return address
  // rsp[8]                   : argument argc
  // rsp[16]                  : argument argc - 1
  // ...
  // rsp[argc * 8]            : argument 1
  // rsp[(argc + 1) * 8]      : argument 0 = receiver
  // -----------------------------------

  // Get the receiver of the function from the stack; 1 ~ return address.
  __ movq(rdx, Operand(rsp, (argc + 1) * kPointerSize));

  Label do_call, slow_call, slow_load;
  Label check_number_dictionary, check_string, lookup_monomorphic_cache;
  Label index_smi, index_string;

  // Check that the key is a smi.
  __ JumpIfNotSmi(rcx, &check_string);

  __ bind(&index_smi);
  // Now the key is known to be a smi. This place is also jumped to from below
  // where a numeric string is converted to a smi.

  GenerateKeyedLoadReceiverCheck(
      masm, rdx, rax, Map::kHasIndexedInterceptor, &slow_call);

  GenerateFastArrayLoad(
      masm, rdx, rcx, rax, rbx, rdi, &check_number_dictionary, &slow_load);
  Counters* counters = masm->isolate()->counters();
  __ IncrementCounter(counters->keyed_call_generic_smi_fast(), 1);

  __ bind(&do_call);
  // receiver in rdx is not used after this point.
  // rcx: key
  // rdi: function
  GenerateFunctionTailCall(masm, argc, &slow_call);

  __ bind(&check_number_dictionary);
  // rax: elements
  // rcx: smi key
  // Check whether the elements is a number dictionary.
  __ CompareRoot(FieldOperand(rax, HeapObject::kMapOffset),
                 Heap::kHashTableMapRootIndex);
  __ j(not_equal, &slow_load);
  __ SmiToInteger32(rbx, rcx);
  // ebx: untagged index
  GenerateNumberDictionaryLoad(masm, &slow_load, rax, rcx, rbx, r9, rdi, rdi);
  __ IncrementCounter(counters->keyed_call_generic_smi_dict(), 1);
  __ jmp(&do_call);

  __ bind(&slow_load);
  // This branch is taken when calling KeyedCallIC_Miss is neither required
  // nor beneficial.
  __ IncrementCounter(counters->keyed_call_generic_slow_load(), 1);
  __ EnterInternalFrame();
  __ push(rcx);  // save the key
  __ push(rdx);  // pass the receiver
  __ push(rcx);  // pass the key
  __ CallRuntime(Runtime::kKeyedGetProperty, 2);
  __ pop(rcx);  // restore the key
  __ LeaveInternalFrame();
  __ movq(rdi, rax);
  __ jmp(&do_call);

  __ bind(&check_string);
  GenerateKeyStringCheck(masm, rcx, rax, rbx, &index_string, &slow_call);

  // The key is known to be a symbol.
  // If the receiver is a regular JS object with slow properties then do
  // a quick inline probe of the receiver's dictionary.
  // Otherwise do the monomorphic cache probe.
  GenerateKeyedLoadReceiverCheck(
      masm, rdx, rax, Map::kHasNamedInterceptor, &lookup_monomorphic_cache);

  __ movq(rbx, FieldOperand(rdx, JSObject::kPropertiesOffset));
  __ CompareRoot(FieldOperand(rbx, HeapObject::kMapOffset),
                 Heap::kHashTableMapRootIndex);
  __ j(not_equal, &lookup_monomorphic_cache);

  GenerateDictionaryLoad(masm, &slow_load, rbx, rcx, rax, rdi, rdi);
  __ IncrementCounter(counters->keyed_call_generic_lookup_dict(), 1);
  __ jmp(&do_call);

  __ bind(&lookup_monomorphic_cache);
  __ IncrementCounter(counters->keyed_call_generic_lookup_cache(), 1);
  GenerateMonomorphicCacheProbe(masm, argc, Code::KEYED_CALL_IC);
  // Fall through on miss.

  __ bind(&slow_call);
  // This branch is taken if:
  // - the receiver requires boxing or access check,
  // - the key is neither smi nor symbol,
  // - the value loaded is not a function,
  // - there is hope that the runtime will create a monomorphic call stub
  //   that will get fetched next time.
  __ IncrementCounter(counters->keyed_call_generic_slow(), 1);
  GenerateMiss(masm, argc);

  __ bind(&index_string);
  __ IndexFromHash(rbx, rcx);
  // Now jump to the place where smi keys are handled.
  __ jmp(&index_smi);
}


void KeyedCallIC::GenerateNormal(MacroAssembler* masm, int argc) {
  // ----------- S t a t e -------------
  // rcx                      : function name
  // rsp[0]                   : return address
  // rsp[8]                   : argument argc
  // rsp[16]                  : argument argc - 1
  // ...
  // rsp[argc * 8]            : argument 1
  // rsp[(argc + 1) * 8]      : argument 0 = receiver
  // -----------------------------------

  // Check if the name is a string.
  Label miss;
  __ JumpIfSmi(rcx, &miss);
  Condition cond = masm->IsObjectStringType(rcx, rax, rax);
  __ j(NegateCondition(cond), &miss);
  GenerateCallNormal(masm, argc);
  __ bind(&miss);
  GenerateMiss(masm, argc);
}


void KeyedCallIC::GenerateMiss(MacroAssembler* masm, int argc) {
  // ----------- S t a t e -------------
  // rcx                      : function name
  // rsp[0]                   : return address
  // rsp[8]                   : argument argc
  // rsp[16]                  : argument argc - 1
  // ...
  // rsp[argc * 8]            : argument 1
  // rsp[(argc + 1) * 8]      : argument 0 = receiver
  // -----------------------------------

  GenerateCallMiss(masm, argc, IC::kKeyedCallIC_Miss);
}


void LoadIC::GenerateMegamorphic(MacroAssembler* masm) {
  // ----------- S t a t e -------------
  //  -- rax    : receiver
  //  -- rcx    : name
  //  -- rsp[0] : return address
  // -----------------------------------

  // Probe the stub cache.
  Code::Flags flags = Code::ComputeFlags(Code::LOAD_IC,
                                         NOT_IN_LOOP,
                                         MONOMORPHIC);
  Isolate::Current()->stub_cache()->GenerateProbe(masm, flags, rax, rcx, rbx,
                                                  rdx);

  // Cache miss: Jump to runtime.
  StubCompiler::GenerateLoadMiss(masm, Code::LOAD_IC);
}


void LoadIC::GenerateNormal(MacroAssembler* masm) {
  // ----------- S t a t e -------------
  //  -- rax    : receiver
  //  -- rcx    : name
  //  -- rsp[0] : return address
  // -----------------------------------
  Label miss;

  GenerateStringDictionaryReceiverCheck(masm, rax, rdx, rbx, &miss);

  //  rdx: elements
  // Search the dictionary placing the result in rax.
  GenerateDictionaryLoad(masm, &miss, rdx, rcx, rbx, rdi, rax);
  __ ret(0);

  // Cache miss: Jump to runtime.
  __ bind(&miss);
  GenerateMiss(masm);
}


void LoadIC::GenerateMiss(MacroAssembler* masm) {
  // ----------- S t a t e -------------
  //  -- rax    : receiver
  //  -- rcx    : name
  //  -- rsp[0] : return address
  // -----------------------------------

  Counters* counters = masm->isolate()->counters();
  __ IncrementCounter(counters->load_miss(), 1);

  __ pop(rbx);
  __ push(rax);  // receiver
  __ push(rcx);  // name
  __ push(rbx);  // return address

  // Perform tail call to the entry.
  ExternalReference ref =
      ExternalReference(IC_Utility(kLoadIC_Miss), masm->isolate());
  __ TailCallExternalReference(ref, 2, 1);
}


bool LoadIC::PatchInlinedLoad(Address address, Object* map, int offset) {
  if (V8::UseCrankshaft()) return false;

  // The address of the instruction following the call.
  Address test_instruction_address =
      address + Assembler::kCallTargetAddressOffset;
  // If the instruction following the call is not a test rax, nothing
  // was inlined.
  if (*test_instruction_address != Assembler::kTestEaxByte) return false;

  Address delta_address = test_instruction_address + 1;
  // The delta to the start of the map check instruction.
  int delta = *reinterpret_cast<int*>(delta_address);

  // The map address is the last 8 bytes of the 10-byte
  // immediate move instruction, so we add 2 to get the
  // offset to the last 8 bytes.
  Address map_address = test_instruction_address + delta + 2;
  *(reinterpret_cast<Object**>(map_address)) = map;

  // The offset is in the 32-bit displacement of a seven byte
  // memory-to-register move instruction (REX.W 0x88 ModR/M disp32),
  // so we add 3 to get the offset of the displacement.
  Address offset_address =
      test_instruction_address + delta + kOffsetToLoadInstruction + 3;
  *reinterpret_cast<int*>(offset_address) = offset - kHeapObjectTag;
  return true;
}


bool LoadIC::PatchInlinedContextualLoad(Address address,
                                        Object* map,
                                        Object* cell,
                                        bool is_dont_delete) {
  // TODO(<bug#>): implement this.
  return false;
}


bool StoreIC::PatchInlinedStore(Address address, Object* map, int offset) {
  if (V8::UseCrankshaft()) return false;

  // The address of the instruction following the call.
  Address test_instruction_address =
      address + Assembler::kCallTargetAddressOffset;

  // If the instruction following the call is not a test rax, nothing
  // was inlined.
  if (*test_instruction_address != Assembler::kTestEaxByte) return false;

  // Extract the encoded deltas from the test rax instruction.
  Address encoded_offsets_address = test_instruction_address + 1;
  int encoded_offsets = *reinterpret_cast<int*>(encoded_offsets_address);
  int delta_to_map_check = -(encoded_offsets & 0xFFFF);
  int delta_to_record_write = encoded_offsets >> 16;

  // Patch the map to check. The map address is the last 8 bytes of
  // the 10-byte immediate move instruction.
  Address map_check_address = test_instruction_address + delta_to_map_check;
  Address map_address = map_check_address + 2;
  *(reinterpret_cast<Object**>(map_address)) = map;

  // Patch the offset in the store instruction. The offset is in the
  // last 4 bytes of a 7 byte register-to-memory move instruction.
  Address offset_address =
      map_check_address + StoreIC::kOffsetToStoreInstruction + 3;
  // The offset should have initial value (kMaxInt - 1), cleared value
  // (-1) or we should be clearing the inlined version.
  ASSERT(*reinterpret_cast<int*>(offset_address) == kMaxInt - 1 ||
         *reinterpret_cast<int*>(offset_address) == -1 ||
         (offset == 0 && map == HEAP->null_value()));
  *reinterpret_cast<int*>(offset_address) = offset - kHeapObjectTag;

  // Patch the offset in the write-barrier code. The offset is the
  // last 4 bytes of a 7 byte lea instruction.
  offset_address = map_check_address + delta_to_record_write + 3;
  // The offset should have initial value (kMaxInt), cleared value
  // (-1) or we should be clearing the inlined version.
  ASSERT(*reinterpret_cast<int*>(offset_address) == kMaxInt ||
         *reinterpret_cast<int*>(offset_address) == -1 ||
         (offset == 0 && map == HEAP->null_value()));
  *reinterpret_cast<int*>(offset_address) = offset - kHeapObjectTag;

  return true;
}


static bool PatchInlinedMapCheck(Address address, Object* map) {
  if (V8::UseCrankshaft()) return false;

  // Arguments are address of start of call sequence that called
  // the IC,
  Address test_instruction_address =
      address + Assembler::kCallTargetAddressOffset;
  // The keyed load has a fast inlined case if the IC call instruction
  // is immediately followed by a test instruction.
  if (*test_instruction_address != Assembler::kTestEaxByte) return false;

  // Fetch the offset from the test instruction to the map compare
  // instructions (starting with the 64-bit immediate mov of the map
  // address). This offset is stored in the last 4 bytes of the 5
  // byte test instruction.
  Address delta_address = test_instruction_address + 1;
  int delta = *reinterpret_cast<int*>(delta_address);
  // Compute the map address.  The map address is in the last 8 bytes
  // of the 10-byte immediate mov instruction (incl. REX prefix), so we add 2
  // to the offset to get the map address.
  Address map_address = test_instruction_address + delta + 2;
  // Patch the map check.
  *(reinterpret_cast<Object**>(map_address)) = map;
  return true;
}


bool KeyedLoadIC::PatchInlinedLoad(Address address, Object* map) {
  return PatchInlinedMapCheck(address, map);
}


bool KeyedStoreIC::PatchInlinedStore(Address address, Object* map) {
  return PatchInlinedMapCheck(address, map);
}


void KeyedLoadIC::GenerateMiss(MacroAssembler* masm) {
  // ----------- S t a t e -------------
  //  -- rax    : key
  //  -- rdx    : receiver
  //  -- rsp[0]  : return address
  // -----------------------------------

  Counters* counters = masm->isolate()->counters();
  __ IncrementCounter(counters->keyed_load_miss(), 1);

  __ pop(rbx);
  __ push(rdx);  // receiver
  __ push(rax);  // name
  __ push(rbx);  // return address

  // Perform tail call to the entry.
  ExternalReference ref
      = ExternalReference(IC_Utility(kKeyedLoadIC_Miss), masm->isolate());
  __ TailCallExternalReference(ref, 2, 1);
}


void KeyedLoadIC::GenerateRuntimeGetProperty(MacroAssembler* masm) {
  // ----------- S t a t e -------------
  //  -- rax    : key
  //  -- rdx    : receiver
  //  -- rsp[0]  : return address
  // -----------------------------------

  __ pop(rbx);
  __ push(rdx);  // receiver
  __ push(rax);  // name
  __ push(rbx);  // return address

  // Perform tail call to the entry.
  __ TailCallRuntime(Runtime::kKeyedGetProperty, 2, 1);
}


void StoreIC::GenerateMegamorphic(MacroAssembler* masm,
                                  StrictModeFlag strict_mode) {
  // ----------- S t a t e -------------
  //  -- rax    : value
  //  -- rcx    : name
  //  -- rdx    : receiver
  //  -- rsp[0] : return address
  // -----------------------------------

  // Get the receiver from the stack and probe the stub cache.
  Code::Flags flags = Code::ComputeFlags(Code::STORE_IC,
                                         NOT_IN_LOOP,
                                         MONOMORPHIC,
                                         strict_mode);
  Isolate::Current()->stub_cache()->GenerateProbe(masm, flags, rdx, rcx, rbx,
                                                  no_reg);

  // Cache miss: Jump to runtime.
  GenerateMiss(masm);
}


void StoreIC::GenerateMiss(MacroAssembler* masm) {
  // ----------- S t a t e -------------
  //  -- rax    : value
  //  -- rcx    : name
  //  -- rdx    : receiver
  //  -- rsp[0] : return address
  // -----------------------------------

  __ pop(rbx);
  __ push(rdx);  // receiver
  __ push(rcx);  // name
  __ push(rax);  // value
  __ push(rbx);  // return address

  // Perform tail call to the entry.
  ExternalReference ref =
      ExternalReference(IC_Utility(kStoreIC_Miss), masm->isolate());
  __ TailCallExternalReference(ref, 3, 1);
}


// The offset from the inlined patch site to the start of the inlined
// store instruction.
const int StoreIC::kOffsetToStoreInstruction = 20;


void StoreIC::GenerateArrayLength(MacroAssembler* masm) {
  // ----------- S t a t e -------------
  //  -- rax    : value
  //  -- rcx    : name
  //  -- rdx    : receiver
  //  -- rsp[0] : return address
  // -----------------------------------
  //
  // This accepts as a receiver anything JSObject::SetElementsLength accepts
  // (currently anything except for external and pixel arrays which means
  // anything with elements of FixedArray type.), but currently is restricted
  // to JSArray.
  // Value must be a number, but only smis are accepted as the most common case.

  Label miss;

  Register receiver = rdx;
  Register value = rax;
  Register scratch = rbx;

  // Check that the receiver isn't a smi.
  __ JumpIfSmi(receiver, &miss);

  // Check that the object is a JS array.
  __ CmpObjectType(receiver, JS_ARRAY_TYPE, scratch);
  __ j(not_equal, &miss);

  // Check that elements are FixedArray.
  // We rely on StoreIC_ArrayLength below to deal with all types of
  // fast elements (including COW).
  __ movq(scratch, FieldOperand(receiver, JSArray::kElementsOffset));
  __ CmpObjectType(scratch, FIXED_ARRAY_TYPE, scratch);
  __ j(not_equal, &miss);

  // Check that value is a smi.
  __ JumpIfNotSmi(value, &miss);

  // Prepare tail call to StoreIC_ArrayLength.
  __ pop(scratch);
  __ push(receiver);
  __ push(value);
  __ push(scratch);  // return address

  ExternalReference ref =
      ExternalReference(IC_Utility(kStoreIC_ArrayLength), masm->isolate());
  __ TailCallExternalReference(ref, 2, 1);

  __ bind(&miss);

  GenerateMiss(masm);
}


void StoreIC::GenerateNormal(MacroAssembler* masm) {
  // ----------- S t a t e -------------
  //  -- rax    : value
  //  -- rcx    : name
  //  -- rdx    : receiver
  //  -- rsp[0] : return address
  // -----------------------------------

  Label miss;

  GenerateStringDictionaryReceiverCheck(masm, rdx, rbx, rdi, &miss);

  GenerateDictionaryStore(masm, &miss, rbx, rcx, rax, r8, r9);
  Counters* counters = masm->isolate()->counters();
  __ IncrementCounter(counters->store_normal_hit(), 1);
  __ ret(0);

  __ bind(&miss);
  __ IncrementCounter(counters->store_normal_miss(), 1);
  GenerateMiss(masm);
}


void StoreIC::GenerateGlobalProxy(MacroAssembler* masm,
                                  StrictModeFlag strict_mode) {
  // ----------- S t a t e -------------
  //  -- rax    : value
  //  -- rcx    : name
  //  -- rdx    : receiver
  //  -- rsp[0] : return address
  // -----------------------------------
  __ pop(rbx);
  __ push(rdx);
  __ push(rcx);
  __ push(rax);
  __ Push(Smi::FromInt(NONE));  // PropertyAttributes
  __ Push(Smi::FromInt(strict_mode));
  __ push(rbx);  // return address

  // Do tail-call to runtime routine.
  __ TailCallRuntime(Runtime::kSetProperty, 5, 1);
}


void KeyedStoreIC::GenerateRuntimeSetProperty(MacroAssembler* masm,
                                              StrictModeFlag strict_mode) {
  // ----------- S t a t e -------------
  //  -- rax     : value
  //  -- rcx     : key
  //  -- rdx     : receiver
  //  -- rsp[0]  : return address
  // -----------------------------------

  __ pop(rbx);
  __ push(rdx);  // receiver
  __ push(rcx);  // key
  __ push(rax);  // value
  __ Push(Smi::FromInt(NONE));          // PropertyAttributes
  __ Push(Smi::FromInt(strict_mode));   // Strict mode.
  __ push(rbx);  // return address

  // Do tail-call to runtime routine.
  __ TailCallRuntime(Runtime::kSetProperty, 5, 1);
}


void KeyedStoreIC::GenerateMiss(MacroAssembler* masm) {
  // ----------- S t a t e -------------
  //  -- rax     : value
  //  -- rcx     : key
  //  -- rdx     : receiver
  //  -- rsp[0]  : return address
  // -----------------------------------

  __ pop(rbx);
  __ push(rdx);  // receiver
  __ push(rcx);  // key
  __ push(rax);  // value
  __ push(rbx);  // return address

  // Do tail-call to runtime routine.
  ExternalReference ref =
      ExternalReference(IC_Utility(kKeyedStoreIC_Miss), masm->isolate());
  __ TailCallExternalReference(ref, 3, 1);
}


#undef __


Condition CompareIC::ComputeCondition(Token::Value op) {
  switch (op) {
    case Token::EQ_STRICT:
    case Token::EQ:
      return equal;
    case Token::LT:
      return less;
    case Token::GT:
      // Reverse left and right operands to obtain ECMA-262 conversion order.
      return less;
    case Token::LTE:
      // Reverse left and right operands to obtain ECMA-262 conversion order.
      return greater_equal;
    case Token::GTE:
      return greater_equal;
    default:
      UNREACHABLE();
      return no_condition;
  }
}


static bool HasInlinedSmiCode(Address address) {
  // The address of the instruction following the call.
  Address test_instruction_address =
      address + Assembler::kCallTargetAddressOffset;

  // If the instruction following the call is not a test al, nothing
  // was inlined.
  return *test_instruction_address == Assembler::kTestAlByte;
}


void CompareIC::UpdateCaches(Handle<Object> x, Handle<Object> y) {
  HandleScope scope;
  Handle<Code> rewritten;
  State previous_state = GetState();

  State state = TargetState(previous_state, HasInlinedSmiCode(address()), x, y);
  if (state == GENERIC) {
    CompareStub stub(GetCondition(), strict(), NO_COMPARE_FLAGS);
    rewritten = stub.GetCode();
  } else {
    ICCompareStub stub(op_, state);
    rewritten = stub.GetCode();
  }
  set_target(*rewritten);

#ifdef DEBUG
  if (FLAG_trace_ic) {
    PrintF("[CompareIC (%s->%s)#%s]\n",
           GetStateName(previous_state),
           GetStateName(state),
           Token::Name(op_));
  }
#endif

  // Activate inlined smi code.
  if (previous_state == UNINITIALIZED) {
    PatchInlinedSmiCode(address());
  }
}

void PatchInlinedSmiCode(Address address) {
  // The address of the instruction following the call.
  Address test_instruction_address =
      address + Assembler::kCallTargetAddressOffset;

  // If the instruction following the call is not a test al, nothing
  // was inlined.
  if (*test_instruction_address != Assembler::kTestAlByte) {
    ASSERT(*test_instruction_address == Assembler::kNopByte);
    return;
  }

  Address delta_address = test_instruction_address + 1;
  // The delta to the start of the map check instruction and the
  // condition code uses at the patched jump.
  int8_t delta = *reinterpret_cast<int8_t*>(delta_address);
  if (FLAG_trace_ic) {
    PrintF("[  patching ic at %p, test=%p, delta=%d\n",
           address, test_instruction_address, delta);
  }

  // Patch with a short conditional jump. There must be a
  // short jump-if-carry/not-carry at this position.
  Address jmp_address = test_instruction_address - delta;
  ASSERT(*jmp_address == Assembler::kJncShortOpcode ||
         *jmp_address == Assembler::kJcShortOpcode);
  Condition cc = *jmp_address == Assembler::kJncShortOpcode
      ? not_zero
      : zero;
  *jmp_address = static_cast<byte>(Assembler::kJccShortPrefix | cc);
}


} }  // namespace v8::internal

#endif  // V8_TARGET_ARCH_X64