js/src/jit/x64/MacroAssembler-x64.h
author Jeff Walden <jwalden@mit.edu>
Sun, 12 May 2019 01:39:15 +0000
changeset 532355 b435e9bb58cc70ce432f6f3fc837fa318d35a637
parent 517028 fdb6f449e8c0858442997e9fdf5d35fbc35d5fec
child 532357 464bde42a1588d89f7822d175f86db7f93d211ea
permissions -rw-r--r--
Bug 1550616 - Move ModuleBuilder into its own header so that module object-related data structures don't depend on EitherParser.h (and therefore all of parsing and tokenizing). r=tcampbell Differential Revision: https://phabricator.services.mozilla.com/D30578

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
 * vim: set ts=8 sts=2 et sw=2 tw=80:
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#ifndef jit_x64_MacroAssembler_x64_h
#define jit_x64_MacroAssembler_x64_h

#include "jit/JitFrames.h"
#include "jit/MoveResolver.h"
#include "jit/x86-shared/MacroAssembler-x86-shared.h"
#include "js/HeapAPI.h"
#include "vm/BigIntType.h"  // JS::BigInt

namespace js {
namespace jit {

struct ImmShiftedTag : public ImmWord {
  explicit ImmShiftedTag(JSValueShiftedTag shtag) : ImmWord((uintptr_t)shtag) {}

  explicit ImmShiftedTag(JSValueType type)
      : ImmWord(uintptr_t(JSValueShiftedTag(JSVAL_TYPE_TO_SHIFTED_TAG(type)))) {
  }
};

struct ImmTag : public Imm32 {
  explicit ImmTag(JSValueTag tag) : Imm32(tag) {}
};

// ScratchTagScope and ScratchTagScopeRelease are used to manage the tag
// register for splitTagForTest(), which has different register management on
// different platforms.  On 64-bit platforms it requires a scratch register that
// does not interfere with other operations; on 32-bit platforms it uses a
// register that is already part of the Value.
//
// The ScratchTagScope RAII type acquires the appropriate register; a reference
// to a variable of this type is then passed to splitTagForTest().
//
// On 64-bit platforms ScratchTagScopeRelease makes the owned scratch register
// available in a dynamic scope during compilation.  However it is important to
// remember that that does not preserve the register value in any way, so this
// RAII type should only be used along paths that eventually branch past further
// uses of the extracted tag value.
//
// On 32-bit platforms ScratchTagScopeRelease has no effect, since it does not
// manage a register, it only aliases a register in the ValueOperand.

class ScratchTagScope : public ScratchRegisterScope {
 public:
  ScratchTagScope(MacroAssembler& masm, const ValueOperand&)
      : ScratchRegisterScope(masm) {}
};

class ScratchTagScopeRelease {
  ScratchTagScope* ts_;

 public:
  explicit ScratchTagScopeRelease(ScratchTagScope* ts) : ts_(ts) {
    ts_->release();
  }
  ~ScratchTagScopeRelease() { ts_->reacquire(); }
};

class MacroAssemblerX64 : public MacroAssemblerX86Shared {
 private:
  // Perform a downcast. Should be removed by Bug 996602.
  MacroAssembler& asMasm();
  const MacroAssembler& asMasm() const;

  void bindOffsets(const MacroAssemblerX86Shared::UsesVector&);

 public:
  using MacroAssemblerX86Shared::load32;
  using MacroAssemblerX86Shared::store16;
  using MacroAssemblerX86Shared::store32;

  MacroAssemblerX64() {}

  // The buffer is about to be linked, make sure any constant pools or excess
  // bookkeeping has been flushed to the instruction stream.
  void finish();

  /////////////////////////////////////////////////////////////////
  // X64 helpers.
  /////////////////////////////////////////////////////////////////
  void writeDataRelocation(const Value& val) {
    if (val.isGCThing()) {
      gc::Cell* cell = val.toGCThing();
      if (cell && gc::IsInsideNursery(cell)) {
        embedsNurseryPointers_ = true;
      }
      dataRelocations_.writeUnsigned(masm.currentOffset());
    }
  }

  // Refers to the upper 32 bits of a 64-bit Value operand.
  // On x86_64, the upper 32 bits do not necessarily only contain the type.
  Operand ToUpper32(Operand base) {
    switch (base.kind()) {
      case Operand::MEM_REG_DISP:
        return Operand(Register::FromCode(base.base()), base.disp() + 4);

      case Operand::MEM_SCALE:
        return Operand(Register::FromCode(base.base()),
                       Register::FromCode(base.index()), base.scale(),
                       base.disp() + 4);

      default:
        MOZ_CRASH("unexpected operand kind");
    }
  }
  static inline Operand ToUpper32(const Address& address) {
    return Operand(address.base, address.offset + 4);
  }
  static inline Operand ToUpper32(const BaseIndex& address) {
    return Operand(address.base, address.index, address.scale,
                   address.offset + 4);
  }

  uint32_t Upper32Of(JSValueShiftedTag tag) {
    union {  // Implemented in this way to appease MSVC++.
      uint64_t tag;
      struct {
        uint32_t lo32;
        uint32_t hi32;
      } s;
    } e;
    e.tag = tag;
    return e.s.hi32;
  }

  JSValueShiftedTag GetShiftedTag(JSValueType type) {
    return (JSValueShiftedTag)JSVAL_TYPE_TO_SHIFTED_TAG(type);
  }

  /////////////////////////////////////////////////////////////////
  // X86/X64-common interface.
  /////////////////////////////////////////////////////////////////
  Address ToPayload(Address value) { return value; }

  void storeValue(ValueOperand val, Operand dest) {
    movq(val.valueReg(), dest);
  }
  void storeValue(ValueOperand val, const Address& dest) {
    storeValue(val, Operand(dest));
  }
  template <typename T>
  void storeValue(JSValueType type, Register reg, const T& dest) {
    // Value types with 32-bit payloads can be emitted as two 32-bit moves.
    if (type == JSVAL_TYPE_INT32 || type == JSVAL_TYPE_BOOLEAN) {
      movl(reg, Operand(dest));
      movl(Imm32(Upper32Of(GetShiftedTag(type))), ToUpper32(Operand(dest)));
    } else {
      ScratchRegisterScope scratch(asMasm());
#ifdef NIGHTLY_BUILD
      // Bug 1485209 - Diagnostic assert for constructing Values with
      // nullptr or misaligned (eg poisoned) JSObject/JSString pointers.
      if (type == JSVAL_TYPE_OBJECT || type == JSVAL_TYPE_STRING) {
        Label crash, ok;
        testPtr(reg, Imm32(js::gc::CellAlignMask));
        j(Assembler::NonZero, &crash);
        testPtr(reg, reg);
        j(Assembler::NonZero, &ok);
        bind(&crash);
        breakpoint();
        bind(&ok);
      }
#endif
      boxValue(type, reg, scratch);
      movq(scratch, Operand(dest));
    }
  }
  template <typename T>
  void storeValue(const Value& val, const T& dest) {
    ScratchRegisterScope scratch(asMasm());
    if (val.isGCThing()) {
      movWithPatch(ImmWord(val.asRawBits()), scratch);
      writeDataRelocation(val);
    } else {
      mov(ImmWord(val.asRawBits()), scratch);
    }
    movq(scratch, Operand(dest));
  }
  void storeValue(ValueOperand val, BaseIndex dest) {
    storeValue(val, Operand(dest));
  }
  void storeValue(const Address& src, const Address& dest, Register temp) {
    loadPtr(src, temp);
    storePtr(temp, dest);
  }
  void loadValue(Operand src, ValueOperand val) { movq(src, val.valueReg()); }
  void loadValue(Address src, ValueOperand val) {
    loadValue(Operand(src), val);
  }
  void loadValue(const BaseIndex& src, ValueOperand val) {
    loadValue(Operand(src), val);
  }
  void tagValue(JSValueType type, Register payload, ValueOperand dest) {
    ScratchRegisterScope scratch(asMasm());
    MOZ_ASSERT(dest.valueReg() != scratch);
    if (payload != dest.valueReg()) {
      movq(payload, dest.valueReg());
    }
    mov(ImmShiftedTag(type), scratch);
    orq(scratch, dest.valueReg());
  }
  void pushValue(ValueOperand val) { push(val.valueReg()); }
  void popValue(ValueOperand val) { pop(val.valueReg()); }
  void pushValue(const Value& val) {
    if (val.isGCThing()) {
      ScratchRegisterScope scratch(asMasm());
      movWithPatch(ImmWord(val.asRawBits()), scratch);
      writeDataRelocation(val);
      push(scratch);
    } else {
      push(ImmWord(val.asRawBits()));
    }
  }
  void pushValue(JSValueType type, Register reg) {
    ScratchRegisterScope scratch(asMasm());
    boxValue(type, reg, scratch);
    push(scratch);
  }
  void pushValue(const Address& addr) { push(Operand(addr)); }

  void boxValue(JSValueType type, Register src, Register dest);

  Condition testUndefined(Condition cond, Register tag) {
    MOZ_ASSERT(cond == Equal || cond == NotEqual);
    cmp32(tag, ImmTag(JSVAL_TAG_UNDEFINED));
    return cond;
  }
  Condition testInt32(Condition cond, Register tag) {
    MOZ_ASSERT(cond == Equal || cond == NotEqual);
    cmp32(tag, ImmTag(JSVAL_TAG_INT32));
    return cond;
  }
  Condition testBoolean(Condition cond, Register tag) {
    MOZ_ASSERT(cond == Equal || cond == NotEqual);
    cmp32(tag, ImmTag(JSVAL_TAG_BOOLEAN));
    return cond;
  }
  Condition testNull(Condition cond, Register tag) {
    MOZ_ASSERT(cond == Equal || cond == NotEqual);
    cmp32(tag, ImmTag(JSVAL_TAG_NULL));
    return cond;
  }
  Condition testString(Condition cond, Register tag) {
    MOZ_ASSERT(cond == Equal || cond == NotEqual);
    cmp32(tag, ImmTag(JSVAL_TAG_STRING));
    return cond;
  }
  Condition testSymbol(Condition cond, Register tag) {
    MOZ_ASSERT(cond == Equal || cond == NotEqual);
    cmp32(tag, ImmTag(JSVAL_TAG_SYMBOL));
    return cond;
  }
  Condition testBigInt(Condition cond, Register tag) {
    MOZ_ASSERT(cond == Equal || cond == NotEqual);
    cmp32(tag, ImmTag(JSVAL_TAG_BIGINT));
    return cond;
  }
  Condition testObject(Condition cond, Register tag) {
    MOZ_ASSERT(cond == Equal || cond == NotEqual);
    cmp32(tag, ImmTag(JSVAL_TAG_OBJECT));
    return cond;
  }
  Condition testDouble(Condition cond, Register tag) {
    MOZ_ASSERT(cond == Equal || cond == NotEqual);
    cmp32(tag, Imm32(JSVAL_TAG_MAX_DOUBLE));
    return cond == Equal ? BelowOrEqual : Above;
  }
  Condition testNumber(Condition cond, Register tag) {
    MOZ_ASSERT(cond == Equal || cond == NotEqual);
    cmp32(tag, Imm32(JSVAL_UPPER_INCL_TAG_OF_NUMBER_SET));
    return cond == Equal ? BelowOrEqual : Above;
  }
  Condition testGCThing(Condition cond, Register tag) {
    MOZ_ASSERT(cond == Equal || cond == NotEqual);
    cmp32(tag, Imm32(JSVAL_LOWER_INCL_TAG_OF_GCTHING_SET));
    return cond == Equal ? AboveOrEqual : Below;
  }

  Condition testMagic(Condition cond, Register tag) {
    MOZ_ASSERT(cond == Equal || cond == NotEqual);
    cmp32(tag, ImmTag(JSVAL_TAG_MAGIC));
    return cond;
  }
  Condition testError(Condition cond, Register tag) {
    return testMagic(cond, tag);
  }
  Condition testPrimitive(Condition cond, Register tag) {
    MOZ_ASSERT(cond == Equal || cond == NotEqual);
    cmp32(tag, ImmTag(JSVAL_UPPER_EXCL_TAG_OF_PRIMITIVE_SET));
    return cond == Equal ? Below : AboveOrEqual;
  }

  Condition testUndefined(Condition cond, const ValueOperand& src) {
    ScratchRegisterScope scratch(asMasm());
    splitTag(src, scratch);
    return testUndefined(cond, scratch);
  }
  Condition testInt32(Condition cond, const ValueOperand& src) {
    ScratchRegisterScope scratch(asMasm());
    splitTag(src, scratch);
    return testInt32(cond, scratch);
  }
  Condition testBoolean(Condition cond, const ValueOperand& src) {
    ScratchRegisterScope scratch(asMasm());
    splitTag(src, scratch);
    return testBoolean(cond, scratch);
  }
  Condition testDouble(Condition cond, const ValueOperand& src) {
    ScratchRegisterScope scratch(asMasm());
    splitTag(src, scratch);
    return testDouble(cond, scratch);
  }
  Condition testNumber(Condition cond, const ValueOperand& src) {
    ScratchRegisterScope scratch(asMasm());
    splitTag(src, scratch);
    return testNumber(cond, scratch);
  }
  Condition testNull(Condition cond, const ValueOperand& src) {
    ScratchRegisterScope scratch(asMasm());
    splitTag(src, scratch);
    return testNull(cond, scratch);
  }
  Condition testString(Condition cond, const ValueOperand& src) {
    ScratchRegisterScope scratch(asMasm());
    splitTag(src, scratch);
    return testString(cond, scratch);
  }
  Condition testSymbol(Condition cond, const ValueOperand& src) {
    ScratchRegisterScope scratch(asMasm());
    splitTag(src, scratch);
    return testSymbol(cond, scratch);
  }
  Condition testBigInt(Condition cond, const ValueOperand& src) {
    ScratchRegisterScope scratch(asMasm());
    splitTag(src, scratch);
    return testBigInt(cond, scratch);
  }
  Condition testObject(Condition cond, const ValueOperand& src) {
    ScratchRegisterScope scratch(asMasm());
    splitTag(src, scratch);
    return testObject(cond, scratch);
  }
  Condition testGCThing(Condition cond, const ValueOperand& src) {
    ScratchRegisterScope scratch(asMasm());
    splitTag(src, scratch);
    return testGCThing(cond, scratch);
  }
  Condition testPrimitive(Condition cond, const ValueOperand& src) {
    ScratchRegisterScope scratch(asMasm());
    splitTag(src, scratch);
    return testPrimitive(cond, scratch);
  }

  Condition testUndefined(Condition cond, const Address& src) {
    cmp32(ToUpper32(src),
          Imm32(Upper32Of(GetShiftedTag(JSVAL_TYPE_UNDEFINED))));
    return cond;
  }
  Condition testInt32(Condition cond, const Address& src) {
    cmp32(ToUpper32(src), Imm32(Upper32Of(GetShiftedTag(JSVAL_TYPE_INT32))));
    return cond;
  }
  Condition testBoolean(Condition cond, const Address& src) {
    cmp32(ToUpper32(src), Imm32(Upper32Of(GetShiftedTag(JSVAL_TYPE_BOOLEAN))));
    return cond;
  }
  Condition testDouble(Condition cond, const Address& src) {
    ScratchRegisterScope scratch(asMasm());
    splitTag(src, scratch);
    return testDouble(cond, scratch);
  }
  Condition testNumber(Condition cond, const Address& src) {
    ScratchRegisterScope scratch(asMasm());
    splitTag(src, scratch);
    return testNumber(cond, scratch);
  }
  Condition testNull(Condition cond, const Address& src) {
    cmp32(ToUpper32(src), Imm32(Upper32Of(GetShiftedTag(JSVAL_TYPE_NULL))));
    return cond;
  }
  Condition testString(Condition cond, const Address& src) {
    ScratchRegisterScope scratch(asMasm());
    splitTag(src, scratch);
    return testString(cond, scratch);
  }
  Condition testSymbol(Condition cond, const Address& src) {
    ScratchRegisterScope scratch(asMasm());
    splitTag(src, scratch);
    return testSymbol(cond, scratch);
  }
  Condition testBigInt(Condition cond, const Address& src) {
    ScratchRegisterScope scratch(asMasm());
    splitTag(src, scratch);
    return testBigInt(cond, scratch);
  }
  Condition testObject(Condition cond, const Address& src) {
    ScratchRegisterScope scratch(asMasm());
    splitTag(src, scratch);
    return testObject(cond, scratch);
  }
  Condition testPrimitive(Condition cond, const Address& src) {
    ScratchRegisterScope scratch(asMasm());
    splitTag(src, scratch);
    return testPrimitive(cond, scratch);
  }
  Condition testGCThing(Condition cond, const Address& src) {
    ScratchRegisterScope scratch(asMasm());
    splitTag(src, scratch);
    return testGCThing(cond, scratch);
  }
  Condition testMagic(Condition cond, const Address& src) {
    ScratchRegisterScope scratch(asMasm());
    splitTag(src, scratch);
    return testMagic(cond, scratch);
  }

  Condition testUndefined(Condition cond, const BaseIndex& src) {
    ScratchRegisterScope scratch(asMasm());
    splitTag(src, scratch);
    return testUndefined(cond, scratch);
  }
  Condition testNull(Condition cond, const BaseIndex& src) {
    ScratchRegisterScope scratch(asMasm());
    splitTag(src, scratch);
    return testNull(cond, scratch);
  }
  Condition testBoolean(Condition cond, const BaseIndex& src) {
    ScratchRegisterScope scratch(asMasm());
    splitTag(src, scratch);
    return testBoolean(cond, scratch);
  }
  Condition testString(Condition cond, const BaseIndex& src) {
    ScratchRegisterScope scratch(asMasm());
    splitTag(src, scratch);
    return testString(cond, scratch);
  }
  Condition testSymbol(Condition cond, const BaseIndex& src) {
    ScratchRegisterScope scratch(asMasm());
    splitTag(src, scratch);
    return testSymbol(cond, scratch);
  }
  Condition testBigInt(Condition cond, const BaseIndex& src) {
    ScratchRegisterScope scratch(asMasm());
    splitTag(src, scratch);
    return testBigInt(cond, scratch);
  }
  Condition testInt32(Condition cond, const BaseIndex& src) {
    ScratchRegisterScope scratch(asMasm());
    splitTag(src, scratch);
    return testInt32(cond, scratch);
  }
  Condition testObject(Condition cond, const BaseIndex& src) {
    ScratchRegisterScope scratch(asMasm());
    splitTag(src, scratch);
    return testObject(cond, scratch);
  }
  Condition testDouble(Condition cond, const BaseIndex& src) {
    ScratchRegisterScope scratch(asMasm());
    splitTag(src, scratch);
    return testDouble(cond, scratch);
  }
  Condition testMagic(Condition cond, const BaseIndex& src) {
    ScratchRegisterScope scratch(asMasm());
    splitTag(src, scratch);
    return testMagic(cond, scratch);
  }
  Condition testGCThing(Condition cond, const BaseIndex& src) {
    ScratchRegisterScope scratch(asMasm());
    splitTag(src, scratch);
    return testGCThing(cond, scratch);
  }

  Condition isMagic(Condition cond, const ValueOperand& src, JSWhyMagic why) {
    uint64_t magic = MagicValue(why).asRawBits();
    cmpPtr(src.valueReg(), ImmWord(magic));
    return cond;
  }

  void cmpPtr(Register lhs, const ImmWord rhs) {
    ScratchRegisterScope scratch(asMasm());
    MOZ_ASSERT(lhs != scratch);
    if (intptr_t(rhs.value) <= INT32_MAX && intptr_t(rhs.value) >= INT32_MIN) {
      cmpPtr(lhs, Imm32(int32_t(rhs.value)));
    } else {
      movePtr(rhs, scratch);
      cmpPtr(lhs, scratch);
    }
  }
  void cmpPtr(Register lhs, const ImmPtr rhs) {
    cmpPtr(lhs, ImmWord(uintptr_t(rhs.value)));
  }
  void cmpPtr(Register lhs, const ImmGCPtr rhs) {
    ScratchRegisterScope scratch(asMasm());
    MOZ_ASSERT(lhs != scratch);
    movePtr(rhs, scratch);
    cmpPtr(lhs, scratch);
  }
  void cmpPtr(Register lhs, const Imm32 rhs) { cmpq(rhs, lhs); }
  void cmpPtr(const Operand& lhs, const ImmGCPtr rhs) {
    ScratchRegisterScope scratch(asMasm());
    MOZ_ASSERT(!lhs.containsReg(scratch));
    movePtr(rhs, scratch);
    cmpPtr(lhs, scratch);
  }
  void cmpPtr(const Operand& lhs, const ImmWord rhs) {
    if ((intptr_t)rhs.value <= INT32_MAX && (intptr_t)rhs.value >= INT32_MIN) {
      cmpPtr(lhs, Imm32((int32_t)rhs.value));
    } else {
      ScratchRegisterScope scratch(asMasm());
      movePtr(rhs, scratch);
      cmpPtr(lhs, scratch);
    }
  }
  void cmpPtr(const Operand& lhs, const ImmPtr rhs) {
    cmpPtr(lhs, ImmWord(uintptr_t(rhs.value)));
  }
  void cmpPtr(const Address& lhs, const ImmGCPtr rhs) {
    cmpPtr(Operand(lhs), rhs);
  }
  void cmpPtr(const Address& lhs, const ImmWord rhs) {
    cmpPtr(Operand(lhs), rhs);
  }
  void cmpPtr(const Address& lhs, const ImmPtr rhs) {
    cmpPtr(lhs, ImmWord(uintptr_t(rhs.value)));
  }
  void cmpPtr(const Operand& lhs, Register rhs) { cmpq(rhs, lhs); }
  void cmpPtr(Register lhs, const Operand& rhs) { cmpq(rhs, lhs); }
  void cmpPtr(const Operand& lhs, const Imm32 rhs) { cmpq(rhs, lhs); }
  void cmpPtr(const Address& lhs, Register rhs) { cmpPtr(Operand(lhs), rhs); }
  void cmpPtr(Register lhs, Register rhs) { cmpq(rhs, lhs); }
  void testPtr(Register lhs, Register rhs) { testq(rhs, lhs); }
  void testPtr(Register lhs, Imm32 rhs) { testq(rhs, lhs); }
  void testPtr(const Operand& lhs, Imm32 rhs) { testq(rhs, lhs); }

  /////////////////////////////////////////////////////////////////
  // Common interface.
  /////////////////////////////////////////////////////////////////

  CodeOffsetJump jumpWithPatch(RepatchLabel* label) {
    JmpSrc src = jmpSrc(label);
    return CodeOffsetJump(size(),
                          addPatchableJump(src, RelocationKind::HARDCODED));
  }

  void movePtr(Register src, Register dest) { movq(src, dest); }
  void movePtr(Register src, const Operand& dest) { movq(src, dest); }
  void movePtr(ImmWord imm, Register dest) { mov(imm, dest); }
  void movePtr(ImmPtr imm, Register dest) { mov(imm, dest); }
  void movePtr(wasm::SymbolicAddress imm, Register dest) { mov(imm, dest); }
  void movePtr(ImmGCPtr imm, Register dest) { movq(imm, dest); }
  void loadPtr(AbsoluteAddress address, Register dest) {
    if (X86Encoding::IsAddressImmediate(address.addr)) {
      movq(Operand(address), dest);
    } else {
      ScratchRegisterScope scratch(asMasm());
      mov(ImmPtr(address.addr), scratch);
      loadPtr(Address(scratch, 0x0), dest);
    }
  }
  void loadPtr(const Address& address, Register dest) {
    movq(Operand(address), dest);
  }
  void load64(const Address& address, Register dest) {
    movq(Operand(address), dest);
  }
  void loadPtr(const Operand& src, Register dest) { movq(src, dest); }
  void loadPtr(const BaseIndex& src, Register dest) {
    movq(Operand(src), dest);
  }
  void loadPrivate(const Address& src, Register dest) {
    loadPtr(src, dest);
    shlq(Imm32(1), dest);
  }
  void load32(AbsoluteAddress address, Register dest) {
    if (X86Encoding::IsAddressImmediate(address.addr)) {
      movl(Operand(address), dest);
    } else {
      ScratchRegisterScope scratch(asMasm());
      mov(ImmPtr(address.addr), scratch);
      load32(Address(scratch, 0x0), dest);
    }
  }
  void load64(const Address& address, Register64 dest) {
    movq(Operand(address), dest.reg);
  }
  template <typename T>
  void storePtr(ImmWord imm, T address) {
    if ((intptr_t)imm.value <= INT32_MAX && (intptr_t)imm.value >= INT32_MIN) {
      movq(Imm32((int32_t)imm.value), Operand(address));
    } else {
      ScratchRegisterScope scratch(asMasm());
      mov(imm, scratch);
      movq(scratch, Operand(address));
    }
  }
  template <typename T>
  void storePtr(ImmPtr imm, T address) {
    storePtr(ImmWord(uintptr_t(imm.value)), address);
  }
  template <typename T>
  void storePtr(ImmGCPtr imm, T address) {
    ScratchRegisterScope scratch(asMasm());
    movq(imm, scratch);
    movq(scratch, Operand(address));
  }
  void storePtr(Register src, const Address& address) {
    movq(src, Operand(address));
  }
  void store64(Register src, const Address& address) {
    movq(src, Operand(address));
  }
  void storePtr(Register src, const BaseIndex& address) {
    movq(src, Operand(address));
  }
  void storePtr(Register src, const Operand& dest) { movq(src, dest); }
  void storePtr(Register src, AbsoluteAddress address) {
    if (X86Encoding::IsAddressImmediate(address.addr)) {
      movq(src, Operand(address));
    } else {
      ScratchRegisterScope scratch(asMasm());
      mov(ImmPtr(address.addr), scratch);
      storePtr(src, Address(scratch, 0x0));
    }
  }
  void store32(Register src, AbsoluteAddress address) {
    if (X86Encoding::IsAddressImmediate(address.addr)) {
      movl(src, Operand(address));
    } else {
      ScratchRegisterScope scratch(asMasm());
      mov(ImmPtr(address.addr), scratch);
      store32(src, Address(scratch, 0x0));
    }
  }
  void store16(Register src, AbsoluteAddress address) {
    if (X86Encoding::IsAddressImmediate(address.addr)) {
      movw(src, Operand(address));
    } else {
      ScratchRegisterScope scratch(asMasm());
      mov(ImmPtr(address.addr), scratch);
      store16(src, Address(scratch, 0x0));
    }
  }
  void store64(Register64 src, Address address) { storePtr(src.reg, address); }
  void store64(Imm64 imm, Address address) {
    storePtr(ImmWord(imm.value), address);
  }

  void splitTag(Register src, Register dest) {
    if (src != dest) {
      movq(src, dest);
    }
    shrq(Imm32(JSVAL_TAG_SHIFT), dest);
  }
  void splitTag(const ValueOperand& operand, Register dest) {
    splitTag(operand.valueReg(), dest);
  }
  void splitTag(const Operand& operand, Register dest) {
    movq(operand, dest);
    shrq(Imm32(JSVAL_TAG_SHIFT), dest);
  }
  void splitTag(const Address& operand, Register dest) {
    splitTag(Operand(operand), dest);
  }
  void splitTag(const BaseIndex& operand, Register dest) {
    splitTag(Operand(operand), dest);
  }

  // Extracts the tag of a value and places it in tag.
  void splitTagForTest(const ValueOperand& value, ScratchTagScope& tag) {
    splitTag(value, tag);
  }
  void cmpTag(const ValueOperand& operand, ImmTag tag) {
    ScratchTagScope reg(asMasm(), operand);
    splitTagForTest(operand, reg);
    cmp32(reg, tag);
  }

  Condition testMagic(Condition cond, const ValueOperand& src) {
    ScratchTagScope scratch(asMasm(), src);
    splitTagForTest(src, scratch);
    return testMagic(cond, scratch);
  }
  Condition testError(Condition cond, const ValueOperand& src) {
    return testMagic(cond, src);
  }

  void testNullSet(Condition cond, const ValueOperand& value, Register dest) {
    cond = testNull(cond, value);
    emitSet(cond, dest);
  }

  void testObjectSet(Condition cond, const ValueOperand& value, Register dest) {
    cond = testObject(cond, value);
    emitSet(cond, dest);
  }

  void testUndefinedSet(Condition cond, const ValueOperand& value,
                        Register dest) {
    cond = testUndefined(cond, value);
    emitSet(cond, dest);
  }

  void boxDouble(FloatRegister src, const ValueOperand& dest, FloatRegister) {
    vmovq(src, dest.valueReg());
  }
  void boxNonDouble(JSValueType type, Register src, const ValueOperand& dest) {
    MOZ_ASSERT(src != dest.valueReg());
    boxValue(type, src, dest.valueReg());
  }

  // Note that the |dest| register here may be ScratchReg, so we shouldn't
  // use it.
  void unboxInt32(const ValueOperand& src, Register dest) {
    movl(src.valueReg(), dest);
  }
  void unboxInt32(const Operand& src, Register dest) { movl(src, dest); }
  void unboxInt32(const Address& src, Register dest) {
    unboxInt32(Operand(src), dest);
  }
  void unboxDouble(const Address& src, FloatRegister dest) {
    loadDouble(Operand(src), dest);
  }

  void unboxArgObjMagic(const ValueOperand& src, Register dest) {
    unboxArgObjMagic(Operand(src.valueReg()), dest);
  }
  void unboxArgObjMagic(const Operand& src, Register dest) {
    mov(ImmWord(0), dest);
  }
  void unboxArgObjMagic(const Address& src, Register dest) {
    unboxArgObjMagic(Operand(src), dest);
  }

  void unboxBoolean(const ValueOperand& src, Register dest) {
    movl(src.valueReg(), dest);
  }
  void unboxBoolean(const Operand& src, Register dest) { movl(src, dest); }
  void unboxBoolean(const Address& src, Register dest) {
    unboxBoolean(Operand(src), dest);
  }

  void unboxMagic(const ValueOperand& src, Register dest) {
    movl(src.valueReg(), dest);
  }

  void unboxDouble(const ValueOperand& src, FloatRegister dest) {
    vmovq(src.valueReg(), dest);
  }
  void unboxPrivate(const ValueOperand& src, const Register dest) {
    movq(src.valueReg(), dest);
    shlq(Imm32(1), dest);
  }

  void notBoolean(const ValueOperand& val) { xorq(Imm32(1), val.valueReg()); }

  void unboxNonDouble(const ValueOperand& src, Register dest,
                      JSValueType type) {
    MOZ_ASSERT(type != JSVAL_TYPE_DOUBLE);
    if (type == JSVAL_TYPE_INT32 || type == JSVAL_TYPE_BOOLEAN) {
      movl(src.valueReg(), dest);
      return;
    }
    if (src.valueReg() == dest) {
      ScratchRegisterScope scratch(asMasm());
      mov(ImmWord(JSVAL_TYPE_TO_SHIFTED_TAG(type)), scratch);
      xorq(scratch, dest);
    } else {
      mov(ImmWord(JSVAL_TYPE_TO_SHIFTED_TAG(type)), dest);
      xorq(src.valueReg(), dest);
    }
  }
  void unboxNonDouble(const Operand& src, Register dest, JSValueType type) {
    MOZ_ASSERT(type != JSVAL_TYPE_DOUBLE);
    if (type == JSVAL_TYPE_INT32 || type == JSVAL_TYPE_BOOLEAN) {
      movl(src, dest);
      return;
    }
    // Explicitly permits |dest| to be used in |src|.
    ScratchRegisterScope scratch(asMasm());
    MOZ_ASSERT(dest != scratch);
    if (src.containsReg(dest)) {
      mov(ImmWord(JSVAL_TYPE_TO_SHIFTED_TAG(type)), scratch);
      // If src is already a register, then src and dest are the same
      // thing and we don't need to move anything into dest.
      if (src.kind() != Operand::REG) {
        movq(src, dest);
      }
      xorq(scratch, dest);
    } else {
      mov(ImmWord(JSVAL_TYPE_TO_SHIFTED_TAG(type)), dest);
      xorq(src, dest);
    }
  }
  void unboxNonDouble(const Address& src, Register dest, JSValueType type) {
    unboxNonDouble(Operand(src), dest, type);
  }
  void unboxNonDouble(const BaseIndex& src, Register dest, JSValueType type) {
    unboxNonDouble(Operand(src), dest, type);
  }

  void unboxString(const ValueOperand& src, Register dest) {
    unboxNonDouble(src, dest, JSVAL_TYPE_STRING);
  }
  void unboxString(const Operand& src, Register dest) {
    unboxNonDouble(src, dest, JSVAL_TYPE_STRING);
  }
  void unboxString(const Address& src, Register dest) {
    unboxNonDouble(src, dest, JSVAL_TYPE_STRING);
  }

  void unboxSymbol(const ValueOperand& src, Register dest) {
    unboxNonDouble(src, dest, JSVAL_TYPE_SYMBOL);
  }
  void unboxSymbol(const Operand& src, Register dest) {
    unboxNonDouble(src, dest, JSVAL_TYPE_SYMBOL);
  }

  void unboxBigInt(const ValueOperand& src, Register dest) {
    unboxNonDouble(src, dest, JSVAL_TYPE_BIGINT);
  }
  void unboxBigInt(const Operand& src, Register dest) {
    unboxNonDouble(src, dest, JSVAL_TYPE_BIGINT);
  }

  void unboxObject(const ValueOperand& src, Register dest) {
    unboxNonDouble(src, dest, JSVAL_TYPE_OBJECT);
  }
  void unboxObject(const Operand& src, Register dest) {
    unboxNonDouble(src, dest, JSVAL_TYPE_OBJECT);
  }
  void unboxObject(const Address& src, Register dest) {
    unboxNonDouble(Operand(src), dest, JSVAL_TYPE_OBJECT);
  }
  void unboxObject(const BaseIndex& src, Register dest) {
    unboxNonDouble(Operand(src), dest, JSVAL_TYPE_OBJECT);
  }

  template <typename T>
  void unboxObjectOrNull(const T& src, Register dest) {
    unboxNonDouble(src, dest, JSVAL_TYPE_OBJECT);
    ScratchRegisterScope scratch(asMasm());
    mov(ImmWord(~JSVAL_OBJECT_OR_NULL_BIT), scratch);
    andq(scratch, dest);
  }

  // This should only be used for the pre-barrier trampoline, to unbox a
  // string/symbol/object Value. It's fine there because we don't depend on
  // the actual Value type. In almost all other cases, this would be
  // Spectre-unsafe - use unboxNonDouble and friends instead.
  void unboxGCThingForPreBarrierTrampoline(const Address& src, Register dest) {
    movq(ImmWord(JSVAL_PAYLOAD_MASK_GCTHING), dest);
    andq(Operand(src), dest);
  }

  // Extended unboxing API. If the payload is already in a register, returns
  // that register. Otherwise, provides a move to the given scratch register,
  // and returns that.
  MOZ_MUST_USE Register extractObject(const Address& address,
                                      Register scratch) {
    MOZ_ASSERT(scratch != ScratchReg);
    unboxObject(address, scratch);
    return scratch;
  }
  MOZ_MUST_USE Register extractObject(const ValueOperand& value,
                                      Register scratch) {
    MOZ_ASSERT(scratch != ScratchReg);
    unboxObject(value, scratch);
    return scratch;
  }
  MOZ_MUST_USE Register extractSymbol(const ValueOperand& value,
                                      Register scratch) {
    MOZ_ASSERT(scratch != ScratchReg);
    unboxSymbol(value, scratch);
    return scratch;
  }
  MOZ_MUST_USE Register extractInt32(const ValueOperand& value,
                                     Register scratch) {
    MOZ_ASSERT(scratch != ScratchReg);
    unboxInt32(value, scratch);
    return scratch;
  }
  MOZ_MUST_USE Register extractBoolean(const ValueOperand& value,
                                       Register scratch) {
    MOZ_ASSERT(scratch != ScratchReg);
    unboxBoolean(value, scratch);
    return scratch;
  }
  MOZ_MUST_USE Register extractTag(const Address& address, Register scratch) {
    MOZ_ASSERT(scratch != ScratchReg);
    loadPtr(address, scratch);
    splitTag(scratch, scratch);
    return scratch;
  }
  MOZ_MUST_USE Register extractTag(const ValueOperand& value,
                                   Register scratch) {
    MOZ_ASSERT(scratch != ScratchReg);
    splitTag(value, scratch);
    return scratch;
  }

  inline void unboxValue(const ValueOperand& src, AnyRegister dest,
                         JSValueType type);

  // These two functions use the low 32-bits of the full value register.
  void boolValueToDouble(const ValueOperand& operand, FloatRegister dest) {
    convertInt32ToDouble(operand.valueReg(), dest);
  }
  void int32ValueToDouble(const ValueOperand& operand, FloatRegister dest) {
    convertInt32ToDouble(operand.valueReg(), dest);
  }

  void boolValueToFloat32(const ValueOperand& operand, FloatRegister dest) {
    convertInt32ToFloat32(operand.valueReg(), dest);
  }
  void int32ValueToFloat32(const ValueOperand& operand, FloatRegister dest) {
    convertInt32ToFloat32(operand.valueReg(), dest);
  }

  void loadConstantDouble(double d, FloatRegister dest);
  void loadConstantFloat32(float f, FloatRegister dest);

  void loadConstantSimd128Int(const SimdConstant& v, FloatRegister dest);
  void loadConstantSimd128Float(const SimdConstant& v, FloatRegister dest);

  void loadWasmGlobalPtr(uint32_t globalDataOffset, Register dest) {
    loadPtr(Address(WasmTlsReg,
                    offsetof(wasm::TlsData, globalArea) + globalDataOffset),
            dest);
  }
  void loadWasmPinnedRegsFromTls() {
    loadPtr(Address(WasmTlsReg, offsetof(wasm::TlsData, memoryBase)), HeapReg);
  }

 public:
  Condition testInt32Truthy(bool truthy, const ValueOperand& operand) {
    test32(operand.valueReg(), operand.valueReg());
    return truthy ? NonZero : Zero;
  }
  Condition testStringTruthy(bool truthy, const ValueOperand& value) {
    ScratchRegisterScope scratch(asMasm());
    unboxString(value, scratch);
    cmp32(Operand(scratch, JSString::offsetOfLength()), Imm32(0));
    return truthy ? Assembler::NotEqual : Assembler::Equal;
  }
  Condition testBigIntTruthy(bool truthy, const ValueOperand& value) {
    ScratchRegisterScope scratch(asMasm());
    unboxBigInt(value, scratch);
    cmpPtr(Operand(scratch, BigInt::offsetOfLengthSignAndReservedBits()),
           ImmWord(0));
    return truthy ? Assembler::NotEqual : Assembler::Equal;
  }

  template <typename T>
  inline void loadInt32OrDouble(const T& src, FloatRegister dest);

  template <typename T>
  void loadUnboxedValue(const T& src, MIRType type, AnyRegister dest) {
    if (dest.isFloat()) {
      loadInt32OrDouble(src, dest.fpu());
    } else if (type == MIRType::ObjectOrNull) {
      unboxObjectOrNull(src, dest.gpr());
    } else {
      unboxNonDouble(Operand(src), dest.gpr(), ValueTypeFromMIRType(type));
    }
  }

  template <typename T>
  void storeUnboxedPayload(ValueOperand value, T address, size_t nbytes,
                           JSValueType type) {
    switch (nbytes) {
      case 8: {
        ScratchRegisterScope scratch(asMasm());
        unboxNonDouble(value, scratch, type);
        storePtr(scratch, address);
        if (type == JSVAL_TYPE_OBJECT) {
          // Ideally we would call unboxObjectOrNull, but we need an extra
          // scratch register for that. So unbox as object, then clear the
          // object-or-null bit.
          mov(ImmWord(~JSVAL_OBJECT_OR_NULL_BIT), scratch);
          andq(scratch, Operand(address));
        }
        return;
      }
      case 4:
        store32(value.valueReg(), address);
        return;
      case 1:
        store8(value.valueReg(), address);
        return;
      default:
        MOZ_CRASH("Bad payload width");
    }
  }

  void loadInstructionPointerAfterCall(Register dest) {
    loadPtr(Address(StackPointer, 0x0), dest);
  }

  void convertUInt32ToDouble(Register src, FloatRegister dest) {
    // Zero the output register to break dependencies, see convertInt32ToDouble.
    zeroDouble(dest);

    vcvtsq2sd(src, dest, dest);
  }

  void convertUInt32ToFloat32(Register src, FloatRegister dest) {
    // Zero the output register to break dependencies, see convertInt32ToDouble.
    zeroDouble(dest);

    vcvtsq2ss(src, dest, dest);
  }

  inline void incrementInt32Value(const Address& addr);

  inline void ensureDouble(const ValueOperand& source, FloatRegister dest,
                           Label* failure);

 public:
  void handleFailureWithHandlerTail(void* handler, Label* profilerExitTail);

  // Instrumentation for entering and leaving the profiler.
  void profilerEnterFrame(Register framePtr, Register scratch);
  void profilerExitFrame();
};

typedef MacroAssemblerX64 MacroAssemblerSpecific;

}  // namespace jit
}  // namespace js

#endif /* jit_x64_MacroAssembler_x64_h */