// Copyright 2012 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef V8_MIPS_MACRO_ASSEMBLER_MIPS_H_
#define V8_MIPS_MACRO_ASSEMBLER_MIPS_H_

#include "src/assembler.h"
#include "src/globals.h"
#include "src/mips/assembler-mips.h"

namespace v8 {
namespace internal {

// Give alias names to registers for calling conventions.
constexpr Register kReturnRegister0 = {Register::kCode_v0};
constexpr Register kReturnRegister1 = {Register::kCode_v1};
constexpr Register kReturnRegister2 = {Register::kCode_a0};
constexpr Register kJSFunctionRegister = {Register::kCode_a1};
constexpr Register kContextRegister = {Register::kCpRegister};
constexpr Register kAllocateSizeRegister = {Register::kCode_a0};
constexpr Register kInterpreterAccumulatorRegister = {Register::kCode_v0};
constexpr Register kInterpreterBytecodeOffsetRegister = {Register::kCode_t4};
constexpr Register kInterpreterBytecodeArrayRegister = {Register::kCode_t5};
constexpr Register kInterpreterDispatchTableRegister = {Register::kCode_t6};
constexpr Register kJavaScriptCallArgCountRegister = {Register::kCode_a0};
constexpr Register kJavaScriptCallNewTargetRegister = {Register::kCode_a3};
constexpr Register kRuntimeCallFunctionRegister = {Register::kCode_a1};
constexpr Register kRuntimeCallArgCountRegister = {Register::kCode_a0};

// Forward declaration.
class JumpTarget;

// Reserved Register Usage Summary.
//
// Registers t8, t9, and at are reserved for use by the MacroAssembler.
//
// The programmer should know that the MacroAssembler may clobber these three,
// but won't touch other registers except in special cases.
//
// Per the MIPS ABI, register t9 must be used for indirect function call
// via 'jalr t9' or 'jr t9' instructions. This is relied upon by gcc when
// trying to update gp register for position-independent-code. Whenever
// MIPS generated code calls C code, it must be via t9 register.


// Flags used for LeaveExitFrame function.
enum LeaveExitFrameMode {
  EMIT_RETURN = true,
  NO_EMIT_RETURN = false
};

// Flags used for AllocateHeapNumber
enum TaggingMode {
  // Tag the result.
  TAG_RESULT,
  // Don't tag
  DONT_TAG_RESULT
};

// Allow programmer to use Branch Delay Slot of Branches, Jumps, Calls.
enum BranchDelaySlot {
  USE_DELAY_SLOT,
  PROTECT
};

// Flags used for the li macro-assembler function.
enum LiFlags {
  // If the constant value can be represented in just 16 bits, then
  // optimize the li to use a single instruction, rather than lui/ori pair.
  OPTIMIZE_SIZE = 0,
  // Always use 2 instructions (lui/ori pair), even if the constant could
  // be loaded with just one, so that this value is patchable later.
  CONSTANT_SIZE = 1
};


enum RememberedSetAction { EMIT_REMEMBERED_SET, OMIT_REMEMBERED_SET };
enum SmiCheck { INLINE_SMI_CHECK, OMIT_SMI_CHECK };
enum PointersToHereCheck {
  kPointersToHereMaybeInteresting,
  kPointersToHereAreAlwaysInteresting
};
enum RAStatus { kRAHasNotBeenSaved, kRAHasBeenSaved };

Register GetRegisterThatIsNotOneOf(Register reg1,
                                   Register reg2 = no_reg,
                                   Register reg3 = no_reg,
                                   Register reg4 = no_reg,
                                   Register reg5 = no_reg,
                                   Register reg6 = no_reg);

bool AreAliased(Register reg1, Register reg2, Register reg3 = no_reg,
                Register reg4 = no_reg, Register reg5 = no_reg,
                Register reg6 = no_reg, Register reg7 = no_reg,
                Register reg8 = no_reg, Register reg9 = no_reg,
                Register reg10 = no_reg);


// -----------------------------------------------------------------------------
// Static helper functions.

inline MemOperand ContextMemOperand(Register context, int index) {
  return MemOperand(context, Context::SlotOffset(index));
}


inline MemOperand NativeContextMemOperand() {
  return ContextMemOperand(cp, Context::NATIVE_CONTEXT_INDEX);
}


// Generate a MemOperand for loading a field from an object.
inline MemOperand FieldMemOperand(Register object, int offset) {
  return MemOperand(object, offset - kHeapObjectTag);
}


// Generate a MemOperand for storing arguments 5..N on the stack
// when calling CallCFunction().
inline MemOperand CFunctionArgumentOperand(int index) {
  DCHECK(index > kCArgSlotCount);
  // Argument 5 takes the slot just past the four Arg-slots.
  int offset = (index - 5) * kPointerSize + kCArgsSlotsSize;
  return MemOperand(sp, offset);
}

class TurboAssembler : public Assembler {
 public:
  TurboAssembler(Isolate* isolate, void* buffer, int buffer_size,
                 CodeObjectRequired create_code_object)
      : Assembler(isolate, buffer, buffer_size),
        isolate_(isolate),
        has_double_zero_reg_set_(false) {
    if (create_code_object == CodeObjectRequired::kYes) {
      code_object_ =
          Handle<HeapObject>::New(isolate->heap()->undefined_value(), isolate);
    }
  }

  void set_has_frame(bool value) { has_frame_ = value; }
  bool has_frame() const { return has_frame_; }

  Isolate* isolate() const { return isolate_; }

  Handle<HeapObject> CodeObject() {
    DCHECK(!code_object_.is_null());
    return code_object_;
  }

  // Activation support.
  void EnterFrame(StackFrame::Type type);
  void EnterFrame(StackFrame::Type type, bool load_constant_pool_pointer_reg) {
    // Out-of-line constant pool not implemented on mips.
    UNREACHABLE();
  }
  void LeaveFrame(StackFrame::Type type);

  // Generates function and stub prologue code.
  void StubPrologue(StackFrame::Type type);
  void Prologue();

  void InitializeRootRegister() {
    ExternalReference roots_array_start =
        ExternalReference::roots_array_start(isolate());
    li(kRootRegister, Operand(roots_array_start));
  }

  // Jump unconditionally to given label.
  // We NEED a nop in the branch delay slot, as it used by v8, for example in
  // CodeGenerator::ProcessDeferred().
  // Currently the branch delay slot is filled by the MacroAssembler.
  // Use rather b(Label) for code generation.
  void jmp(Label* L) { Branch(L); }

  // -------------------------------------------------------------------------
  // Debugging.

  // Calls Abort(msg) if the condition cc is not satisfied.
  // Use --debug_code to enable.
  void Assert(Condition cc, BailoutReason reason, Register rs, Operand rt);

  // Like Assert(), but always enabled.
  void Check(Condition cc, BailoutReason reason, Register rs, Operand rt);

  // Print a message to stdout and abort execution.
  void Abort(BailoutReason msg);

  inline bool AllowThisStubCall(CodeStub* stub);

  // Arguments macros.
#define COND_TYPED_ARGS Condition cond, Register r1, const Operand& r2
#define COND_ARGS cond, r1, r2

  // Cases when relocation is not needed.
#define DECLARE_NORELOC_PROTOTYPE(Name, target_type) \
  void Name(target_type target, BranchDelaySlot bd = PROTECT); \
  inline void Name(BranchDelaySlot bd, target_type target) { \
    Name(target, bd); \
  } \
  void Name(target_type target, \
            COND_TYPED_ARGS, \
            BranchDelaySlot bd = PROTECT); \
  inline void Name(BranchDelaySlot bd, \
                   target_type target, \
                   COND_TYPED_ARGS) { \
    Name(target, COND_ARGS, bd); \
  }

#define DECLARE_BRANCH_PROTOTYPES(Name)   \
  DECLARE_NORELOC_PROTOTYPE(Name, Label*) \
  DECLARE_NORELOC_PROTOTYPE(Name, int32_t)

  DECLARE_BRANCH_PROTOTYPES(Branch)
  DECLARE_BRANCH_PROTOTYPES(BranchAndLink)
  DECLARE_BRANCH_PROTOTYPES(BranchShort)

#undef DECLARE_BRANCH_PROTOTYPES
#undef COND_TYPED_ARGS
#undef COND_ARGS

  // Wrapper functions for the different cmp/branch types.
  inline void BranchF32(Label* target, Label* nan, Condition cc,
                        FPURegister cmp1, FPURegister cmp2,
                        BranchDelaySlot bd = PROTECT) {
    BranchFCommon(S, target, nan, cc, cmp1, cmp2, bd);
  }

  inline void BranchF64(Label* target, Label* nan, Condition cc,
                        FPURegister cmp1, FPURegister cmp2,
                        BranchDelaySlot bd = PROTECT) {
    BranchFCommon(D, target, nan, cc, cmp1, cmp2, bd);
  }

  // Alternate (inline) version for better readability with USE_DELAY_SLOT.
  inline void BranchF64(BranchDelaySlot bd, Label* target, Label* nan,
                        Condition cc, FPURegister cmp1, FPURegister cmp2) {
    BranchF64(target, nan, cc, cmp1, cmp2, bd);
  }

  inline void BranchF32(BranchDelaySlot bd, Label* target, Label* nan,
                        Condition cc, FPURegister cmp1, FPURegister cmp2) {
    BranchF32(target, nan, cc, cmp1, cmp2, bd);
  }

  void BranchMSA(Label* target, MSABranchDF df, MSABranchCondition cond,
                 MSARegister wt, BranchDelaySlot bd = PROTECT);

  void Branch(Label* L, Condition cond, Register rs, Heap::RootListIndex index,
              BranchDelaySlot bdslot = PROTECT);

  // Load int32 in the rd register.
  void li(Register rd, Operand j, LiFlags mode = OPTIMIZE_SIZE);
  inline void li(Register rd, int32_t j, LiFlags mode = OPTIMIZE_SIZE) {
    li(rd, Operand(j), mode);
  }
  void li(Register dst, Handle<HeapObject> value, LiFlags mode = OPTIMIZE_SIZE);

  // Jump, Call, and Ret pseudo instructions implementing inter-working.
#define COND_ARGS Condition cond = al, Register rs = zero_reg, \
  const Operand& rt = Operand(zero_reg), BranchDelaySlot bd = PROTECT

  void Jump(Register target, int16_t offset = 0, COND_ARGS);
  void Jump(Register target, Register base, int16_t offset = 0, COND_ARGS);
  void Jump(Register target, const Operand& offset, COND_ARGS);
  void Jump(intptr_t target, RelocInfo::Mode rmode, COND_ARGS);
  void Jump(Address target, RelocInfo::Mode rmode, COND_ARGS);
  void Jump(Handle<Code> code, RelocInfo::Mode rmode, COND_ARGS);
  static int CallSize(Register target, int16_t offset = 0, COND_ARGS);
  void Call(Register target, int16_t offset = 0, COND_ARGS);
  void Call(Register target, Register base, int16_t offset = 0, COND_ARGS);
  static int CallSize(Address target, RelocInfo::Mode rmode, COND_ARGS);
  void Call(Address target, RelocInfo::Mode rmode, COND_ARGS);
  int CallSize(Handle<Code> code,
               RelocInfo::Mode rmode = RelocInfo::CODE_TARGET,
               COND_ARGS);
  void Call(Handle<Code> code,
            RelocInfo::Mode rmode = RelocInfo::CODE_TARGET,
            COND_ARGS);
  void Call(Label* target);

  void CallForDeoptimization(Address target, RelocInfo::Mode rmode) {
    Call(target, rmode);
  }

  void Ret(COND_ARGS);
  inline void Ret(BranchDelaySlot bd, Condition cond = al,
    Register rs = zero_reg, const Operand& rt = Operand(zero_reg)) {
    Ret(cond, rs, rt, bd);
  }

  // Emit code to discard a non-negative number of pointer-sized elements
  // from the stack, clobbering only the sp register.
  void Drop(int count,
            Condition cond = cc_always,
            Register reg = no_reg,
            const Operand& op = Operand(no_reg));

  // Trivial case of DropAndRet that utilizes the delay slot and only emits
  // 2 instructions.
  void DropAndRet(int drop);

  void DropAndRet(int drop,
                  Condition cond,
                  Register reg,
                  const Operand& op);

  void push(Register src) {
    Addu(sp, sp, Operand(-kPointerSize));
    sw(src, MemOperand(sp, 0));
  }

  void Push(Register src) { push(src); }
  void Push(Handle<HeapObject> handle);
  void Push(Smi* smi);

  // Push two registers. Pushes leftmost register first (to highest address).
  void Push(Register src1, Register src2) {
    Subu(sp, sp, Operand(2 * kPointerSize));
    sw(src1, MemOperand(sp, 1 * kPointerSize));
    sw(src2, MemOperand(sp, 0 * kPointerSize));
  }

  // Push three registers. Pushes leftmost register first (to highest address).
  void Push(Register src1, Register src2, Register src3) {
    Subu(sp, sp, Operand(3 * kPointerSize));
    sw(src1, MemOperand(sp, 2 * kPointerSize));
    sw(src2, MemOperand(sp, 1 * kPointerSize));
    sw(src3, MemOperand(sp, 0 * kPointerSize));
  }

  // Push four registers. Pushes leftmost register first (to highest address).
  void Push(Register src1, Register src2, Register src3, Register src4) {
    Subu(sp, sp, Operand(4 * kPointerSize));
    sw(src1, MemOperand(sp, 3 * kPointerSize));
    sw(src2, MemOperand(sp, 2 * kPointerSize));
    sw(src3, MemOperand(sp, 1 * kPointerSize));
    sw(src4, MemOperand(sp, 0 * kPointerSize));
  }

  // Push five registers. Pushes leftmost register first (to highest address).
  void Push(Register src1, Register src2, Register src3, Register src4,
            Register src5) {
    Subu(sp, sp, Operand(5 * kPointerSize));
    sw(src1, MemOperand(sp, 4 * kPointerSize));
    sw(src2, MemOperand(sp, 3 * kPointerSize));
    sw(src3, MemOperand(sp, 2 * kPointerSize));
    sw(src4, MemOperand(sp, 1 * kPointerSize));
    sw(src5, MemOperand(sp, 0 * kPointerSize));
  }

  void Push(Register src, Condition cond, Register tst1, Register tst2) {
    // Since we don't have conditional execution we use a Branch.
    Branch(3, cond, tst1, Operand(tst2));
    Subu(sp, sp, Operand(kPointerSize));
    sw(src, MemOperand(sp, 0));
  }

  // Push multiple registers on the stack.
  // Registers are saved in numerical order, with higher numbered registers
  // saved in higher memory addresses.
  void MultiPush(RegList regs);
  void MultiPushFPU(RegList regs);

  void PushCallerSaved(SaveFPRegsMode fp_mode, Register exclusion1 = no_reg,
                       Register exclusion2 = no_reg,
                       Register exclusion3 = no_reg);
  void PopCallerSaved(SaveFPRegsMode fp_mode, Register exclusion1 = no_reg,
                      Register exclusion2 = no_reg,
                      Register exclusion3 = no_reg);

  void pop(Register dst) {
    lw(dst, MemOperand(sp, 0));
    Addu(sp, sp, Operand(kPointerSize));
  }

  void Pop(Register dst) { pop(dst); }

  // Pop two registers. Pops rightmost register first (from lower address).
  void Pop(Register src1, Register src2) {
    DCHECK(!src1.is(src2));
    lw(src2, MemOperand(sp, 0 * kPointerSize));
    lw(src1, MemOperand(sp, 1 * kPointerSize));
    Addu(sp, sp, 2 * kPointerSize);
  }

  // Pop three registers. Pops rightmost register first (from lower address).
  void Pop(Register src1, Register src2, Register src3) {
    lw(src3, MemOperand(sp, 0 * kPointerSize));
    lw(src2, MemOperand(sp, 1 * kPointerSize));
    lw(src1, MemOperand(sp, 2 * kPointerSize));
    Addu(sp, sp, 3 * kPointerSize);
  }

  void Pop(uint32_t count = 1) { Addu(sp, sp, Operand(count * kPointerSize)); }

  // Pops multiple values from the stack and load them in the
  // registers specified in regs. Pop order is the opposite as in MultiPush.
  void MultiPop(RegList regs);
  void MultiPopFPU(RegList regs);

  // Load Scaled Address instructions. Parameter sa (shift argument) must be
  // between [1, 31] (inclusive). On pre-r6 architectures the scratch register
  // may be clobbered.
  void Lsa(Register rd, Register rs, Register rt, uint8_t sa,
           Register scratch = at);

#define DEFINE_INSTRUCTION(instr)                          \
  void instr(Register rd, Register rs, const Operand& rt); \
  void instr(Register rd, Register rs, Register rt) {      \
    instr(rd, rs, Operand(rt));                            \
  }                                                        \
  void instr(Register rs, Register rt, int32_t j) { instr(rs, rt, Operand(j)); }

#define DEFINE_INSTRUCTION2(instr)                                 \
  void instr(Register rs, const Operand& rt);                      \
  void instr(Register rs, Register rt) { instr(rs, Operand(rt)); } \
  void instr(Register rs, int32_t j) { instr(rs, Operand(j)); }

#define DEFINE_INSTRUCTION3(instr)                                             \
  void instr(Register rd_hi, Register rd_lo, Register rs, const Operand& rt);  \
  void instr(Register rd_hi, Register rd_lo, Register rs, Register rt) {       \
    instr(rd_hi, rd_lo, rs, Operand(rt));                                      \
  }                                                                            \
  void instr(Register rd_hi, Register rd_lo, Register rs, int32_t j) {         \
    instr(rd_hi, rd_lo, rs, Operand(j));                                       \
  }

  DEFINE_INSTRUCTION(Addu);
  DEFINE_INSTRUCTION(Subu);
  DEFINE_INSTRUCTION(Mul);
  DEFINE_INSTRUCTION(Div);
  DEFINE_INSTRUCTION(Divu);
  DEFINE_INSTRUCTION(Mod);
  DEFINE_INSTRUCTION(Modu);
  DEFINE_INSTRUCTION(Mulh);
  DEFINE_INSTRUCTION2(Mult);
  DEFINE_INSTRUCTION(Mulhu);
  DEFINE_INSTRUCTION2(Multu);
  DEFINE_INSTRUCTION2(Div);
  DEFINE_INSTRUCTION2(Divu);

  DEFINE_INSTRUCTION3(Div);
  DEFINE_INSTRUCTION3(Mul);
  DEFINE_INSTRUCTION3(Mulu);

  DEFINE_INSTRUCTION(And);
  DEFINE_INSTRUCTION(Or);
  DEFINE_INSTRUCTION(Xor);
  DEFINE_INSTRUCTION(Nor);
  DEFINE_INSTRUCTION2(Neg);

  DEFINE_INSTRUCTION(Slt);
  DEFINE_INSTRUCTION(Sltu);

  // MIPS32 R2 instruction macro.
  DEFINE_INSTRUCTION(Ror);

#undef DEFINE_INSTRUCTION
#undef DEFINE_INSTRUCTION2
#undef DEFINE_INSTRUCTION3

  void SmiUntag(Register reg) { sra(reg, reg, kSmiTagSize); }

  void SmiUntag(Register dst, Register src) { sra(dst, src, kSmiTagSize); }

  // Removes current frame and its arguments from the stack preserving
  // the arguments and a return address pushed to the stack for the next call.
  // Both |callee_args_count| and |caller_args_count_reg| do not include
  // receiver. |callee_args_count| is not modified, |caller_args_count_reg|
  // is trashed.
  void PrepareForTailCall(const ParameterCount& callee_args_count,
                          Register caller_args_count_reg, Register scratch0,
                          Register scratch1);

  int CalculateStackPassedWords(int num_reg_arguments,
                                int num_double_arguments);

  // Before calling a C-function from generated code, align arguments on stack
  // and add space for the four mips argument slots.
  // After aligning the frame, non-register arguments must be stored on the
  // stack, after the argument-slots using helper: CFunctionArgumentOperand().
  // The argument count assumes all arguments are word sized.
  // Some compilers/platforms require the stack to be aligned when calling
  // C++ code.
  // Needs a scratch register to do some arithmetic. This register will be
  // trashed.
  void PrepareCallCFunction(int num_reg_arguments, int num_double_registers,
                            Register scratch);
  void PrepareCallCFunction(int num_reg_arguments, Register scratch);

  // Arguments 1-4 are placed in registers a0 through a3 respectively.
  // Arguments 5..n are stored to stack using following:
  //  sw(t0, CFunctionArgumentOperand(5));

  // Calls a C function and cleans up the space for arguments allocated
  // by PrepareCallCFunction. The called function is not allowed to trigger a
  // garbage collection, since that might move the code and invalidate the
  // return address (unless this is somehow accounted for by the called
  // function).
  void CallCFunction(ExternalReference function, int num_arguments);
  void CallCFunction(Register function, int num_arguments);
  void CallCFunction(ExternalReference function, int num_reg_arguments,
                     int num_double_arguments);
  void CallCFunction(Register function, int num_reg_arguments,
                     int num_double_arguments);
  void MovFromFloatResult(DoubleRegister dst);
  void MovFromFloatParameter(DoubleRegister dst);

  // There are two ways of passing double arguments on MIPS, depending on
  // whether soft or hard floating point ABI is used. These functions
  // abstract parameter passing for the three different ways we call
  // C functions from generated code.
  void MovToFloatParameter(DoubleRegister src);
  void MovToFloatParameters(DoubleRegister src1, DoubleRegister src2);
  void MovToFloatResult(DoubleRegister src);

  // See comments at the beginning of CEntryStub::Generate.
  inline void PrepareCEntryArgs(int num_args) { li(a0, num_args); }
  inline void PrepareCEntryFunction(const ExternalReference& ref) {
    li(a1, Operand(ref));
  }

  void CheckPageFlag(Register object, Register scratch, int mask, Condition cc,
                     Label* condition_met);

  void CallStubDelayed(CodeStub* stub, COND_ARGS);
#undef COND_ARGS

  void CallRuntimeDelayed(Zone* zone, Runtime::FunctionId fid,
                          SaveFPRegsMode save_doubles = kDontSaveFPRegs,
                          BranchDelaySlot bd = PROTECT);

  // Performs a truncating conversion of a floating point number as used by
  // the JS bitwise operations. See ECMA-262 9.5: ToInt32. Goes to 'done' if it
  // succeeds, otherwise falls through if result is saturated. On return
  // 'result' either holds answer, or is clobbered on fall through.
  //
  // Only public for the test code in test-code-stubs-arm.cc.
  void TryInlineTruncateDoubleToI(Register result, DoubleRegister input,
                                  Label* done);

  // Performs a truncating conversion of a floating point number as used by
  // the JS bitwise operations. See ECMA-262 9.5: ToInt32.
  // Exits with 'result' holding the answer.
  void TruncateDoubleToIDelayed(Zone* zone, Register result,
                                DoubleRegister double_input);

  // Conditional move.
  void Movz(Register rd, Register rs, Register rt);
  void Movn(Register rd, Register rs, Register rt);
  void Movt(Register rd, Register rs, uint16_t cc = 0);
  void Movf(Register rd, Register rs, uint16_t cc = 0);

  void Clz(Register rd, Register rs);

  // Int64Lowering instructions
  void AddPair(Register dst_low, Register dst_high, Register left_low,
               Register left_high, Register right_low, Register right_high);

  void SubPair(Register dst_low, Register dst_high, Register left_low,
               Register left_high, Register right_low, Register right_high);

  void ShlPair(Register dst_low, Register dst_high, Register src_low,
               Register src_high, Register shift);

  void ShlPair(Register dst_low, Register dst_high, Register src_low,
               Register src_high, uint32_t shift);

  void ShrPair(Register dst_low, Register dst_high, Register src_low,
               Register src_high, Register shift);

  void ShrPair(Register dst_low, Register dst_high, Register src_low,
               Register src_high, uint32_t shift);

  void SarPair(Register dst_low, Register dst_high, Register src_low,
               Register src_high, Register shift);

  void SarPair(Register dst_low, Register dst_high, Register src_low,
               Register src_high, uint32_t shift);

  // MIPS32 R2 instruction macro.
  void Ins(Register rt, Register rs, uint16_t pos, uint16_t size);
  void Ext(Register rt, Register rs, uint16_t pos, uint16_t size);
  void ExtractBits(Register dest, Register source, Register pos, int size,
                   bool sign_extend = false);
  void InsertBits(Register dest, Register source, Register pos, int size);

  void Seb(Register rd, Register rt);
  void Seh(Register rd, Register rt);
  void Neg_s(FPURegister fd, FPURegister fs);
  void Neg_d(FPURegister fd, FPURegister fs);

  // MIPS32 R6 instruction macros.
  void Bovc(Register rt, Register rs, Label* L);
  void Bnvc(Register rt, Register rs, Label* L);

  // Convert single to unsigned word.
  void Trunc_uw_s(FPURegister fd, FPURegister fs, FPURegister scratch);
  void Trunc_uw_s(FPURegister fd, Register rs, FPURegister scratch);

  // FP32 mode: Move the general purpose register into
  // the high part of the double-register pair.
  // FP64 mode: Move the general-purpose register into
  // the higher 32 bits of the 64-bit coprocessor register,
  // while leaving the low bits unchanged.
  void Mthc1(Register rt, FPURegister fs);

  // FP32 mode: move the high part of the double-register pair into
  // general purpose register.
  // FP64 mode: Move the higher 32 bits of the 64-bit coprocessor register into
  // general-purpose register.
  void Mfhc1(Register rt, FPURegister fs);

  void Madd_s(FPURegister fd, FPURegister fr, FPURegister fs, FPURegister ft,
              FPURegister scratch);
  void Madd_d(FPURegister fd, FPURegister fr, FPURegister fs, FPURegister ft,
              FPURegister scratch);
  void Msub_s(FPURegister fd, FPURegister fr, FPURegister fs, FPURegister ft,
              FPURegister scratch);
  void Msub_d(FPURegister fd, FPURegister fr, FPURegister fs, FPURegister ft,
              FPURegister scratch);

  // Change endianness
  void ByteSwapSigned(Register dest, Register src, int operand_size);
  void ByteSwapUnsigned(Register dest, Register src, int operand_size);

  void Ulh(Register rd, const MemOperand& rs);
  void Ulhu(Register rd, const MemOperand& rs);
  void Ush(Register rd, const MemOperand& rs, Register scratch);

  void Ulw(Register rd, const MemOperand& rs);
  void Usw(Register rd, const MemOperand& rs);

  void Ulwc1(FPURegister fd, const MemOperand& rs, Register scratch);
  void Uswc1(FPURegister fd, const MemOperand& rs, Register scratch);

  void Uldc1(FPURegister fd, const MemOperand& rs, Register scratch);
  void Usdc1(FPURegister fd, const MemOperand& rs, Register scratch);

  void Ldc1(FPURegister fd, const MemOperand& src);
  void Sdc1(FPURegister fs, const MemOperand& dst);

  void Ll(Register rd, const MemOperand& rs);
  void Sc(Register rd, const MemOperand& rs);

  // Perform a floating-point min or max operation with the
  // (IEEE-754-compatible) semantics of MIPS32's Release 6 MIN.fmt/MAX.fmt.
  // Some cases, typically NaNs or +/-0.0, are expected to be rare and are
  // handled in out-of-line code. The specific behaviour depends on supported
  // instructions.
  //
  // These functions assume (and assert) that !src1.is(src2). It is permitted
  // for the result to alias either input register.
  void Float32Max(FPURegister dst, FPURegister src1, FPURegister src2,
                  Label* out_of_line);
  void Float32Min(FPURegister dst, FPURegister src1, FPURegister src2,
                  Label* out_of_line);
  void Float64Max(DoubleRegister dst, DoubleRegister src1, DoubleRegister src2,
                  Label* out_of_line);
  void Float64Min(DoubleRegister dst, DoubleRegister src1, DoubleRegister src2,
                  Label* out_of_line);

  // Generate out-of-line cases for the macros above.
  void Float32MaxOutOfLine(FPURegister dst, FPURegister src1, FPURegister src2);
  void Float32MinOutOfLine(FPURegister dst, FPURegister src1, FPURegister src2);
  void Float64MaxOutOfLine(DoubleRegister dst, DoubleRegister src1,
                           DoubleRegister src2);
  void Float64MinOutOfLine(DoubleRegister dst, DoubleRegister src1,
                           DoubleRegister src2);

  bool IsDoubleZeroRegSet() { return has_double_zero_reg_set_; }

  void mov(Register rd, Register rt) { or_(rd, rt, zero_reg); }

  inline void Move(Register dst, Handle<HeapObject> handle) { li(dst, handle); }
  inline void Move(Register dst, Smi* smi) { li(dst, Operand(smi)); }

  inline void Move(Register dst, Register src) {
    if (!dst.is(src)) {
      mov(dst, src);
    }
  }

  inline void Move_d(FPURegister dst, FPURegister src) {
    if (!dst.is(src)) {
      mov_d(dst, src);
    }
  }

  inline void Move_s(FPURegister dst, FPURegister src) {
    if (!dst.is(src)) {
      mov_s(dst, src);
    }
  }

  inline void Move(FPURegister dst, FPURegister src) { Move_d(dst, src); }

  inline void Move(Register dst_low, Register dst_high, FPURegister src) {
    mfc1(dst_low, src);
    Mfhc1(dst_high, src);
  }

  inline void FmoveHigh(Register dst_high, FPURegister src) {
    Mfhc1(dst_high, src);
  }

  inline void FmoveHigh(FPURegister dst, Register src_high) {
    Mthc1(src_high, dst);
  }

  inline void FmoveLow(Register dst_low, FPURegister src) {
    mfc1(dst_low, src);
  }

  void FmoveLow(FPURegister dst, Register src_low);

  inline void Move(FPURegister dst, Register src_low, Register src_high) {
    mtc1(src_low, dst);
    Mthc1(src_high, dst);
  }

  void Move(FPURegister dst, float imm);
  void Move(FPURegister dst, double imm);

  // -------------------------------------------------------------------------
  // Overflow handling functions.
  // Usage: first call the appropriate arithmetic function, then call one of the
  // jump functions with the overflow_dst register as the second parameter.

  inline void AddBranchOvf(Register dst, Register left, const Operand& right,
                           Label* overflow_label, Register scratch = at) {
    AddBranchOvf(dst, left, right, overflow_label, nullptr, scratch);
  }

  inline void AddBranchNoOvf(Register dst, Register left, const Operand& right,
                             Label* no_overflow_label, Register scratch = at) {
    AddBranchOvf(dst, left, right, nullptr, no_overflow_label, scratch);
  }

  void AddBranchOvf(Register dst, Register left, const Operand& right,
                    Label* overflow_label, Label* no_overflow_label,
                    Register scratch = at);

  void AddBranchOvf(Register dst, Register left, Register right,
                    Label* overflow_label, Label* no_overflow_label,
                    Register scratch = at);

  inline void SubBranchOvf(Register dst, Register left, const Operand& right,
                           Label* overflow_label, Register scratch = at) {
    SubBranchOvf(dst, left, right, overflow_label, nullptr, scratch);
  }

  inline void SubBranchNoOvf(Register dst, Register left, const Operand& right,
                             Label* no_overflow_label, Register scratch = at) {
    SubBranchOvf(dst, left, right, nullptr, no_overflow_label, scratch);
  }

  void SubBranchOvf(Register dst, Register left, const Operand& right,
                    Label* overflow_label, Label* no_overflow_label,
                    Register scratch = at);

  void SubBranchOvf(Register dst, Register left, Register right,
                    Label* overflow_label, Label* no_overflow_label,
                    Register scratch = at);

  inline void MulBranchOvf(Register dst, Register left, const Operand& right,
                           Label* overflow_label, Register scratch = at) {
    MulBranchOvf(dst, left, right, overflow_label, nullptr, scratch);
  }

  inline void MulBranchNoOvf(Register dst, Register left, const Operand& right,
                             Label* no_overflow_label, Register scratch = at) {
    MulBranchOvf(dst, left, right, nullptr, no_overflow_label, scratch);
  }

  void MulBranchOvf(Register dst, Register left, const Operand& right,
                    Label* overflow_label, Label* no_overflow_label,
                    Register scratch = at);

  void MulBranchOvf(Register dst, Register left, Register right,
                    Label* overflow_label, Label* no_overflow_label,
                    Register scratch = at);

// Number of instructions needed for calculation of switch table entry address
#ifdef _MIPS_ARCH_MIPS32R6
  static constexpr int kSwitchTablePrologueSize = 5;
#else
  static constexpr int kSwitchTablePrologueSize = 10;
#endif
  // GetLabelFunction must be lambda '[](size_t index) -> Label*' or a
  // functor/function with 'Label *func(size_t index)' declaration.
  template <typename Func>
  void GenerateSwitchTable(Register index, size_t case_count,
                           Func GetLabelFunction);

  // Load an object from the root table.
  void LoadRoot(Register destination, Heap::RootListIndex index);
  void LoadRoot(Register destination, Heap::RootListIndex index, Condition cond,
                Register src1, const Operand& src2);

  // If the value is a NaN, canonicalize the value else, do nothing.
  void FPUCanonicalizeNaN(const DoubleRegister dst, const DoubleRegister src);

  // ---------------------------------------------------------------------------
  // FPU macros. These do not handle special cases like NaN or +- inf.

  // Convert unsigned word to double.
  void Cvt_d_uw(FPURegister fd, Register rs, FPURegister scratch);

  // Convert double to unsigned word.
  void Trunc_uw_d(FPURegister fd, FPURegister fs, FPURegister scratch);
  void Trunc_uw_d(FPURegister fd, Register rs, FPURegister scratch);

  // Jump the register contains a smi.
  void JumpIfSmi(Register value, Label* smi_label, Register scratch = at,
                 BranchDelaySlot bd = PROTECT);

  // Push a standard frame, consisting of ra, fp, context and JS function.
  void PushStandardFrame(Register function_reg);

  // Get the actual activation frame alignment for target environment.
  static int ActivationFrameAlignment();

  // Alias functions for backward compatibility.
  inline void BranchF(Label* target, Label* nan, Condition cc, FPURegister cmp1,
                      FPURegister cmp2, BranchDelaySlot bd = PROTECT) {
    BranchF64(target, nan, cc, cmp1, cmp2, bd);
  }

  inline void BranchF(BranchDelaySlot bd, Label* target, Label* nan,
                      Condition cc, FPURegister cmp1, FPURegister cmp2) {
    BranchF64(bd, target, nan, cc, cmp1, cmp2);
  }

 protected:
  void BranchLong(Label* L, BranchDelaySlot bdslot);

  inline Register GetRtAsRegisterHelper(const Operand& rt, Register scratch);

  inline int32_t GetOffset(int32_t offset, Label* L, OffsetSize bits);

 private:
  bool has_frame_ = false;
  Isolate* const isolate_;
  // This handle will be patched with the code object on installation.
  Handle<HeapObject> code_object_;
  bool has_double_zero_reg_set_;

  void CallCFunctionHelper(Register function_base, int16_t function_offset,
                           int num_reg_arguments, int num_double_arguments);

  // Common implementation of BranchF functions for the different formats.
  void BranchFCommon(SecondaryField sizeField, Label* target, Label* nan,
                     Condition cc, FPURegister cmp1, FPURegister cmp2,
                     BranchDelaySlot bd = PROTECT);

  void BranchShortF(SecondaryField sizeField, Label* target, Condition cc,
                    FPURegister cmp1, FPURegister cmp2,
                    BranchDelaySlot bd = PROTECT);

  void BranchShortMSA(MSABranchDF df, Label* target, MSABranchCondition cond,
                      MSARegister wt, BranchDelaySlot bd = PROTECT);

  bool CalculateOffset(Label* L, int32_t& offset, OffsetSize bits);
  bool CalculateOffset(Label* L, int32_t& offset, OffsetSize bits,
                       Register& scratch, const Operand& rt);

  void BranchShortHelperR6(int32_t offset, Label* L);
  void BranchShortHelper(int16_t offset, Label* L, BranchDelaySlot bdslot);
  bool BranchShortHelperR6(int32_t offset, Label* L, Condition cond,
                           Register rs, const Operand& rt);
  bool BranchShortHelper(int16_t offset, Label* L, Condition cond, Register rs,
                         const Operand& rt, BranchDelaySlot bdslot);
  bool BranchShortCheck(int32_t offset, Label* L, Condition cond, Register rs,
                        const Operand& rt, BranchDelaySlot bdslot);

  void BranchAndLinkShortHelperR6(int32_t offset, Label* L);
  void BranchAndLinkShortHelper(int16_t offset, Label* L,
                                BranchDelaySlot bdslot);
  void BranchAndLinkShort(int32_t offset, BranchDelaySlot bdslot = PROTECT);
  void BranchAndLinkShort(Label* L, BranchDelaySlot bdslot = PROTECT);
  bool BranchAndLinkShortHelperR6(int32_t offset, Label* L, Condition cond,
                                  Register rs, const Operand& rt);
  bool BranchAndLinkShortHelper(int16_t offset, Label* L, Condition cond,
                                Register rs, const Operand& rt,
                                BranchDelaySlot bdslot);
  bool BranchAndLinkShortCheck(int32_t offset, Label* L, Condition cond,
                               Register rs, const Operand& rt,
                               BranchDelaySlot bdslot);
  void BranchAndLinkLong(Label* L, BranchDelaySlot bdslot);

  // Push a fixed frame, consisting of ra, fp.
  void PushCommonFrame(Register marker_reg = no_reg);
};

// MacroAssembler implements a collection of frequently used macros.
class MacroAssembler : public TurboAssembler {
 public:
  MacroAssembler(Isolate* isolate, void* buffer, int size,
                 CodeObjectRequired create_code_object);

  // Emit code that loads |parameter_index|'th parameter from the stack to
  // the register according to the CallInterfaceDescriptor definition.
  // |sp_to_caller_sp_offset_in_words| specifies the number of words pushed
  // below the caller's sp.
  template <class Descriptor>
  void LoadParameterFromStack(
      Register reg, typename Descriptor::ParameterIndices parameter_index,
      int sp_to_ra_offset_in_words = 0) {
    DCHECK(Descriptor::kPassLastArgsOnStack);
    UNIMPLEMENTED();
  }

  // Swap two registers.  If the scratch register is omitted then a slightly
  // less efficient form using xor instead of mov is emitted.
  void Swap(Register reg1, Register reg2, Register scratch = no_reg);

  void PushRoot(Heap::RootListIndex index) {
    UseScratchRegisterScope temps(this);
    Register scratch = temps.Acquire();
    LoadRoot(scratch, index);
    Push(scratch);
  }

  // Compare the object in a register to a value and jump if they are equal.
  void JumpIfRoot(Register with, Heap::RootListIndex index, Label* if_equal) {
    UseScratchRegisterScope temps(this);
    Register scratch = temps.Acquire();
    LoadRoot(scratch, index);
    Branch(if_equal, eq, with, Operand(scratch));
  }

  // Compare the object in a register to a value and jump if they are not equal.
  void JumpIfNotRoot(Register with, Heap::RootListIndex index,
                     Label* if_not_equal) {
    UseScratchRegisterScope temps(this);
    Register scratch = temps.Acquire();
    LoadRoot(scratch, index);
    Branch(if_not_equal, ne, with, Operand(scratch));
  }

  // ---------------------------------------------------------------------------
  // GC Support

  void IncrementalMarkingRecordWriteHelper(Register object, Register value,
                                           Register address);

  enum RememberedSetFinalAction { kReturnAtEnd, kFallThroughAtEnd };

  // Record in the remembered set the fact that we have a pointer to new space
  // at the address pointed to by the addr register.  Only works if addr is not
  // in new space.
  void RememberedSetHelper(Register object,  // Used for debug code.
                           Register addr, Register scratch,
                           SaveFPRegsMode save_fp,
                           RememberedSetFinalAction and_then);

  // Check if object is in new space.  Jumps if the object is not in new space.
  // The register scratch can be object itself, but it will be clobbered.
  void JumpIfNotInNewSpace(Register object, Register scratch, Label* branch) {
    InNewSpace(object, scratch, eq, branch);
  }

  // Check if object is in new space.  Jumps if the object is in new space.
  // The register scratch can be object itself, but scratch will be clobbered.
  void JumpIfInNewSpace(Register object, Register scratch, Label* branch) {
    InNewSpace(object, scratch, ne, branch);
  }

  // Check if an object has a given incremental marking color.
  void HasColor(Register object, Register scratch0, Register scratch1,
                Label* has_color, int first_bit, int second_bit);

  void JumpIfBlack(Register object, Register scratch0, Register scratch1,
                   Label* on_black);

  // Checks the color of an object.  If the object is white we jump to the
  // incremental marker.
  void JumpIfWhite(Register value, Register scratch1, Register scratch2,
                   Register scratch3, Label* value_is_white);

  // Notify the garbage collector that we wrote a pointer into an object.
  // |object| is the object being stored into, |value| is the object being
  // stored.  value and scratch registers are clobbered by the operation.
  // The offset is the offset from the start of the object, not the offset from
  // the tagged HeapObject pointer.  For use with FieldOperand(reg, off).
  void RecordWriteField(
      Register object, int offset, Register value, Register scratch,
      RAStatus ra_status, SaveFPRegsMode save_fp,
      RememberedSetAction remembered_set_action = EMIT_REMEMBERED_SET,
      SmiCheck smi_check = INLINE_SMI_CHECK,
      PointersToHereCheck pointers_to_here_check_for_value =
          kPointersToHereMaybeInteresting);

  // As above, but the offset has the tag presubtracted.  For use with
  // MemOperand(reg, off).
  inline void RecordWriteContextSlot(
      Register context, int offset, Register value, Register scratch,
      RAStatus ra_status, SaveFPRegsMode save_fp,
      RememberedSetAction remembered_set_action = EMIT_REMEMBERED_SET,
      SmiCheck smi_check = INLINE_SMI_CHECK,
      PointersToHereCheck pointers_to_here_check_for_value =
          kPointersToHereMaybeInteresting) {
    RecordWriteField(context, offset + kHeapObjectTag, value, scratch,
                     ra_status, save_fp, remembered_set_action, smi_check,
                     pointers_to_here_check_for_value);
  }

  void RecordWriteForMap(Register object, Register map, Register dst,
                         RAStatus ra_status, SaveFPRegsMode save_fp);

  // For a given |object| notify the garbage collector that the slot |address|
  // has been written.  |value| is the object being stored. The value and
  // address registers are clobbered by the operation.
  void RecordWrite(
      Register object, Register address, Register value, RAStatus ra_status,
      SaveFPRegsMode save_fp,
      RememberedSetAction remembered_set_action = EMIT_REMEMBERED_SET,
      SmiCheck smi_check = INLINE_SMI_CHECK,
      PointersToHereCheck pointers_to_here_check_for_value =
          kPointersToHereMaybeInteresting);

  // ---------------------------------------------------------------------------
  // Allocation support.

  // Allocate an object in new space or old space. The object_size is
  // specified either in bytes or in words if the allocation flag SIZE_IN_WORDS
  // is passed. If the space is exhausted control continues at the gc_required
  // label. The allocated object is returned in result. If the flag
  // tag_allocated_object is true the result is tagged as as a heap object.
  // All registers are clobbered also when control continues at the gc_required
  // label.
  void Allocate(int object_size, Register result, Register scratch1,
                Register scratch2, Label* gc_required, AllocationFlags flags);

  // Allocate and initialize a JSValue wrapper with the specified {constructor}
  // and {value}.
  void AllocateJSValue(Register result, Register constructor, Register value,
                       Register scratch1, Register scratch2,
                       Label* gc_required);

  void Pref(int32_t hint, const MemOperand& rs);

  // Push and pop the registers that can hold pointers, as defined by the
  // RegList constant kSafepointSavedRegisters.
  void PushSafepointRegisters();
  void PopSafepointRegisters();

  void Trunc_w_d(FPURegister fd, FPURegister fs);
  void Round_w_d(FPURegister fd, FPURegister fs);
  void Floor_w_d(FPURegister fd, FPURegister fs);
  void Ceil_w_d(FPURegister fd, FPURegister fs);

  // Truncates a double using a specific rounding mode, and writes the value
  // to the result register.
  // The except_flag will contain any exceptions caused by the instruction.
  // If check_inexact is kDontCheckForInexactConversion, then the inexact
  // exception is masked.
  void EmitFPUTruncate(
      FPURoundingMode rounding_mode, Register result,
      DoubleRegister double_input, Register scratch,
      DoubleRegister double_scratch, Register except_flag,
      CheckForInexactConversion check_inexact = kDontCheckForInexactConversion);

  // Enter exit frame.
  // argc - argument count to be dropped by LeaveExitFrame.
  // save_doubles - saves FPU registers on stack, currently disabled.
  // stack_space - extra stack space.
  void EnterExitFrame(bool save_doubles, int stack_space = 0,
                      StackFrame::Type frame_type = StackFrame::EXIT);

  // Leave the current exit frame.
  void LeaveExitFrame(bool save_doubles, Register arg_count,
                      bool restore_context, bool do_return = NO_EMIT_RETURN,
                      bool argument_count_is_length = false);

  // Make sure the stack is aligned. Only emits code in debug mode.
  void AssertStackIsAligned();

  // Load the global object from the current context.
  void LoadGlobalObject(Register dst) {
    LoadNativeContextSlot(Context::EXTENSION_INDEX, dst);
  }

  // Load the global proxy from the current context.
  void LoadGlobalProxy(Register dst) {
    LoadNativeContextSlot(Context::GLOBAL_PROXY_INDEX, dst);
  }

  void LoadNativeContextSlot(int index, Register dst);

  // Load the initial map from the global function. The registers
  // function and map can be the same, function is then overwritten.
  void LoadGlobalFunctionInitialMap(Register function,
                                    Register map,
                                    Register scratch);

  // -------------------------------------------------------------------------
  // JavaScript invokes.

  // Invoke the JavaScript function code by either calling or jumping.
  void InvokeFunctionCode(Register function, Register new_target,
                          const ParameterCount& expected,
                          const ParameterCount& actual, InvokeFlag flag);

  // On function call, call into the debugger if necessary.
  void CheckDebugHook(Register fun, Register new_target,
                      const ParameterCount& expected,
                      const ParameterCount& actual);

  // Invoke the JavaScript function in the given register. Changes the
  // current context to the context in the function before invoking.
  void InvokeFunction(Register function, Register new_target,
                      const ParameterCount& actual, InvokeFlag flag);

  void InvokeFunction(Register function, const ParameterCount& expected,
                      const ParameterCount& actual, InvokeFlag flag);

  void InvokeFunction(Handle<JSFunction> function,
                      const ParameterCount& expected,
                      const ParameterCount& actual, InvokeFlag flag);

  // Frame restart support.
  void MaybeDropFrames();

  // Exception handling.

  // Push a new stack handler and link into stack handler chain.
  void PushStackHandler();

  // Unlink the stack handler on top of the stack from the stack handler chain.
  // Must preserve the result register.
  void PopStackHandler();

  // -------------------------------------------------------------------------
  // Support functions.

  // Machine code version of Map::GetConstructor().
  // |temp| holds |result|'s map when done, and |temp2| its instance type.
  void GetMapConstructor(Register result, Register map, Register temp,
                         Register temp2);

  void GetObjectType(Register function,
                     Register map,
                     Register type_reg);

  void GetInstanceType(Register object_map, Register object_instance_type) {
    lbu(object_instance_type,
        FieldMemOperand(object_map, Map::kInstanceTypeOffset));
  }

  // Compare an object's map with the specified map and its transitioned
  // elements maps if mode is ALLOW_ELEMENT_TRANSITION_MAPS. Jumps to
  // "branch_to" if the result of the comparison is "cond". If multiple map
  // compares are required, the compare sequences branches to early_success.
  void CompareMapAndBranch(Register obj,
                           Register scratch,
                           Handle<Map> map,
                           Label* early_success,
                           Condition cond,
                           Label* branch_to);

  // As above, but the map of the object is already loaded into the register
  // which is preserved by the code generated.
  void CompareMapAndBranch(Register obj_map,
                           Handle<Map> map,
                           Label* early_success,
                           Condition cond,
                           Label* branch_to);

  // Check if the map of an object is equal to a specified map and branch to
  // label if not. Skip the smi check if not required (object is known to be a
  // heap object). If mode is ALLOW_ELEMENT_TRANSITION_MAPS, then also match
  // against maps that are ElementsKind transition maps of the specificed map.
  void CheckMap(Register obj,
                Register scratch,
                Handle<Map> map,
                Label* fail,
                SmiCheckType smi_check_type);


  void CheckMap(Register obj,
                Register scratch,
                Heap::RootListIndex index,
                Label* fail,
                SmiCheckType smi_check_type);

  // Get value of the weak cell.
  void GetWeakValue(Register value, Handle<WeakCell> cell);

  // Load the value of the weak cell in the value register. Branch to the
  // given miss label is the weak cell was cleared.
  void LoadWeakValue(Register value, Handle<WeakCell> cell, Label* miss);

  // -------------------------------------------------------------------------
  // Runtime calls.

#define COND_ARGS Condition cond = al, Register rs = zero_reg, \
const Operand& rt = Operand(zero_reg), BranchDelaySlot bd = PROTECT

  // Call a code stub.
  void CallStub(CodeStub* stub,
                COND_ARGS);

  // Tail call a code stub (jump).
  void TailCallStub(CodeStub* stub, COND_ARGS);

#undef COND_ARGS

  // Call a runtime routine.
  void CallRuntime(const Runtime::Function* f, int num_arguments,
                   SaveFPRegsMode save_doubles = kDontSaveFPRegs,
                   BranchDelaySlot bd = PROTECT);

  // Convenience function: Same as above, but takes the fid instead.
  void CallRuntime(Runtime::FunctionId fid,
                   SaveFPRegsMode save_doubles = kDontSaveFPRegs,
                   BranchDelaySlot bd = PROTECT) {
    const Runtime::Function* function = Runtime::FunctionForId(fid);
    CallRuntime(function, function->nargs, save_doubles, bd);
  }

  // Convenience function: Same as above, but takes the fid instead.
  void CallRuntime(Runtime::FunctionId id, int num_arguments,
                   SaveFPRegsMode save_doubles = kDontSaveFPRegs,
                   BranchDelaySlot bd = PROTECT) {
    CallRuntime(Runtime::FunctionForId(id), num_arguments, save_doubles, bd);
  }

  // Convenience function: tail call a runtime routine (jump).
  void TailCallRuntime(Runtime::FunctionId fid);

  // Jump to the builtin routine.
  void JumpToExternalReference(const ExternalReference& builtin,
                               BranchDelaySlot bd = PROTECT,
                               bool builtin_exit_frame = false);

  // -------------------------------------------------------------------------
  // StatsCounter support.

  void IncrementCounter(StatsCounter* counter, int value,
                        Register scratch1, Register scratch2);
  void DecrementCounter(StatsCounter* counter, int value,
                        Register scratch1, Register scratch2);

  // -------------------------------------------------------------------------
  // Smi utilities.

  void SmiTag(Register reg) {
    Addu(reg, reg, reg);
  }

  void SmiTag(Register dst, Register src) { Addu(dst, src, src); }

  // Test if the register contains a smi.
  inline void SmiTst(Register value, Register scratch) {
    And(scratch, value, Operand(kSmiTagMask));
  }

  // Untag the source value into destination and jump if source is a smi.
  // Souce and destination can be the same register.
  void UntagAndJumpIfSmi(Register dst, Register src, Label* smi_case);

  // Jump if the register contains a non-smi.
  void JumpIfNotSmi(Register value,
                    Label* not_smi_label,
                    Register scratch = at,
                    BranchDelaySlot bd = PROTECT);

  // Jump if either of the registers contain a smi.
  void JumpIfEitherSmi(Register reg1, Register reg2, Label* on_either_smi);

  // Abort execution if argument is a smi, enabled via --debug-code.
  void AssertNotSmi(Register object);
  void AssertSmi(Register object);

  // Abort execution if argument is not a FixedArray, enabled via --debug-code.
  void AssertFixedArray(Register object);

  // Abort execution if argument is not a JSFunction, enabled via --debug-code.
  void AssertFunction(Register object);

  // Abort execution if argument is not a JSBoundFunction,
  // enabled via --debug-code.
  void AssertBoundFunction(Register object);

  // Abort execution if argument is not a JSGeneratorObject (or subclass),
  // enabled via --debug-code.
  void AssertGeneratorObject(Register object);

  // Abort execution if argument is not undefined or an AllocationSite, enabled
  // via --debug-code.
  void AssertUndefinedOrAllocationSite(Register object, Register scratch);

  // -------------------------------------------------------------------------
  // String utilities.

  // Checks if both instance types are sequential ASCII strings and jumps to
  // label if either is not.
  void JumpIfBothInstanceTypesAreNotSequentialOneByte(
      Register first_object_instance_type, Register second_object_instance_type,
      Register scratch1, Register scratch2, Label* failure);

  void JumpIfNotUniqueNameInstanceType(Register reg, Label* not_unique_name);

  // Checks if both objects are sequential one-byte strings and jumps to label
  // if either is not. Assumes that neither object is a smi.
  void JumpIfNonSmisNotBothSequentialOneByteStrings(Register first,
                                                    Register second,
                                                    Register scratch1,
                                                    Register scratch2,
                                                    Label* failure);

  void LoadInstanceDescriptors(Register map, Register descriptors);
  void LoadAccessor(Register dst, Register holder, int accessor_index,
                    AccessorComponent accessor);

  template<typename Field>
  void DecodeField(Register dst, Register src) {
    Ext(dst, src, Field::kShift, Field::kSize);
  }

  template<typename Field>
  void DecodeField(Register reg) {
    DecodeField<Field>(reg, reg);
  }

  void EnterBuiltinFrame(Register context, Register target, Register argc);
  void LeaveBuiltinFrame(Register context, Register target, Register argc);


 private:
  // Helper functions for generating invokes.
  void InvokePrologue(const ParameterCount& expected,
                      const ParameterCount& actual, Label* done,
                      bool* definitely_mismatches, InvokeFlag flag);

  // Helper for implementing JumpIfNotInNewSpace and JumpIfInNewSpace.
  void InNewSpace(Register object, Register scratch,
                  Condition cond,  // ne for new space, eq otherwise.
                  Label* branch);

  // Helper for finding the mark bits for an address.  Afterwards, the
  // bitmap register points at the word with the mark bits and the mask
  // the position of the first bit.  Leaves addr_reg unchanged.
  inline void GetMarkBits(Register addr_reg,
                          Register bitmap_reg,
                          Register mask_reg);

  // Compute memory operands for safepoint stack slots.
  static int SafepointRegisterStackIndex(int reg_code);

  // Needs access to SafepointRegisterStackIndex for compiled frame
  // traversal.
  friend class StandardFrame;
};

// The code patcher is used to patch (typically) small parts of code e.g. for
// debugging and other types of instrumentation. When using the code patcher
// the exact number of bytes specified must be emitted. It is not legal to emit
// relocation information. If any of these constraints are violated it causes
// an assertion to fail.
class CodePatcher {
 public:
  enum FlushICache {
    FLUSH,
    DONT_FLUSH
  };

  CodePatcher(Isolate* isolate, byte* address, int instructions,
              FlushICache flush_cache = FLUSH);
  ~CodePatcher();

  // Macro assembler to emit code.
  MacroAssembler* masm() { return &masm_; }

  // Emit an instruction directly.
  void Emit(Instr instr);

  // Emit an address directly.
  void Emit(Address addr);

  // Change the condition part of an instruction leaving the rest of the current
  // instruction unchanged.
  void ChangeBranchCondition(Instr current_instr, uint32_t new_opcode);

 private:
  byte* address_;  // The address of the code being patched.
  int size_;  // Number of bytes of the expected patch size.
  MacroAssembler masm_;  // Macro assembler used to generate the code.
  FlushICache flush_cache_;  // Whether to flush the I cache after patching.
};

template <typename Func>
void TurboAssembler::GenerateSwitchTable(Register index, size_t case_count,
                                         Func GetLabelFunction) {
  Label here;
  BlockTrampolinePoolFor(case_count + kSwitchTablePrologueSize);
  UseScratchRegisterScope temps(this);
  Register scratch = temps.Acquire();
  if (kArchVariant >= kMips32r6) {
    addiupc(scratch, 5);
    Lsa(scratch, scratch, index, kPointerSizeLog2);
    lw(scratch, MemOperand(scratch));
  } else {
    push(ra);
    bal(&here);
    sll(scratch, index, kPointerSizeLog2);  // Branch delay slot.
    bind(&here);
    addu(scratch, scratch, ra);
    pop(ra);
    lw(scratch, MemOperand(scratch, 6 * v8::internal::Assembler::kInstrSize));
  }
  jr(scratch);
  nop();  // Branch delay slot nop.
  for (size_t index = 0; index < case_count; ++index) {
    dd(GetLabelFunction(index));
  }
}

#define ACCESS_MASM(masm) masm->

}  // namespace internal
}  // namespace v8

#endif  // V8_MIPS_MACRO_ASSEMBLER_MIPS_H_
