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 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-

  * vim: set ts=8 sts=4 et sw=4 tw=99:

  * 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_x86_MacroAssembler_x86_h

 #define jit_x86_MacroAssembler_x86_h

 #include "jscompartment.h"

 #include "jit/IonFrames.h"

 #include "jit/MoveResolver.h"

 #include "jit/shared/MacroAssembler-x86-shared.h"

 namespace js {

 namespace jit {

 class MacroAssemblerX86 : public MacroAssemblerX86Shared

 {

     // Number of bytes the stack is adjusted inside a call to C. Calls to C may

     // not be nested.

     bool inCall_;

     uint32_t args_;

     uint32_t passedArgs_;

     uint32_t stackForCall_;

     bool dynamicAlignment_;

     bool enoughMemory_;

     struct Double {

         double value;

         AbsoluteLabel uses;

         Double(double value) : value(value) {}

     };

     Vector<Double, 0, SystemAllocPolicy> doubles_;

     struct Float {

         float value;

         AbsoluteLabel uses;

         Float(float value) : value(value) {}

     };

     Vector<Float, 0, SystemAllocPolicy> floats_;

     typedef HashMap<double, size_t, DefaultHasher<double>, SystemAllocPolicy> DoubleMap;

     DoubleMap doubleMap_;

     typedef HashMap<float, size_t, DefaultHasher<float>, SystemAllocPolicy> FloatMap;

     FloatMap floatMap_;

     Double *getDouble(double d);

     Float *getFloat(float f);

   protected:

     MoveResolver moveResolver_;

   private:

     Operand payloadOf(const Address &address) {

         return Operand(address.base, address.offset);

     }

     Operand tagOf(const Address &address) {

         return Operand(address.base, address.offset + 4);

     }

     Operand tagOf(const BaseIndex &address) {

         return Operand(address.base, address.index, address.scale, address.offset + 4);

     }

     void setupABICall(uint32_t args);

   public:

     using MacroAssemblerX86Shared::Push;

     using MacroAssemblerX86Shared::Pop;

     using MacroAssemblerX86Shared::callWithExitFrame;

     using MacroAssemblerX86Shared::branch32;

     using MacroAssemblerX86Shared::load32;

     using MacroAssemblerX86Shared::store32;

     using MacroAssemblerX86Shared::call;

     MacroAssemblerX86()

       : inCall_(false),

         enoughMemory_(true)

     {

     }

     // The buffer is about to be linked, make sure any constant pools or excess

     // bookkeeping has been flushed to the instruction stream.

     void finish();

     bool oom() const {

         return MacroAssemblerX86Shared::oom() || !enoughMemory_;

     }

     /////////////////////////////////////////////////////////////////

     // X86-specific interface.

     /////////////////////////////////////////////////////////////////

     Operand ToPayload(Operand base) {

         return base;

     }

     Address ToPayload(Address base) {

         return base;

     }

     Operand ToType(Operand base) {

         switch (base.kind()) {

           case Operand::MEM_REG_DISP:

             return Operand(Register::FromCode(base.base()), base.disp() + sizeof(void *));

           case Operand::MEM_SCALE:

             return Operand(Register::FromCode(base.base()), Register::FromCode(base.index()),

                            base.scale(), base.disp() + sizeof(void *));

           default:

             MOZ_ASSUME_UNREACHABLE("unexpected operand kind");

         }

     }

     Address ToType(Address base) {

         return ToType(Operand(base)).toAddress();

     }

     void moveValue(const Value &val, Register type, Register data) {

         jsval_layout jv = JSVAL_TO_IMPL(val);

         movl(Imm32(jv.s.tag), type);

         if (val.isMarkable())

             movl(ImmGCPtr(reinterpret_cast<gc::Cell *>(val.toGCThing())), data);

         else

             movl(Imm32(jv.s.payload.i32), data);

     }

     void moveValue(const Value &val, const ValueOperand &dest) {

         moveValue(val, dest.typeReg(), dest.payloadReg());

     }

     void moveValue(const ValueOperand &src, const ValueOperand &dest) {

         Register s0 = src.typeReg(), d0 = dest.typeReg(),

                  s1 = src.payloadReg(), d1 = dest.payloadReg();

         // Either one or both of the source registers could be the same as a

         // destination register.

         if (s1 == d0) {

             if (s0 == d1) {

                 // If both are, this is just a swap of two registers.

                 xchgl(d0, d1);

                 return;

             }

             // If only one is, copy that source first.

             mozilla::Swap(s0, s1);

             mozilla::Swap(d0, d1);

         }

         if (s0 != d0)

             movl(s0, d0);

         if (s1 != d1)

             movl(s1, d1);

     }

     /////////////////////////////////////////////////////////////////

     // X86/X64-common interface.

     /////////////////////////////////////////////////////////////////

     void storeValue(ValueOperand val, Operand dest) {

         movl(val.payloadReg(), ToPayload(dest));

         movl(val.typeReg(), ToType(dest));

     }

     void storeValue(ValueOperand val, const Address &dest) {

         storeValue(val, Operand(dest));

     }

     template <typename T>

     void storeValue(JSValueType type, Register reg, const T &dest) {

         storeTypeTag(ImmTag(JSVAL_TYPE_TO_TAG(type)), Operand(dest));

         storePayload(reg, Operand(dest));

     }

     template <typename T>

     void storeValue(const Value &val, const T &dest) {

         jsval_layout jv = JSVAL_TO_IMPL(val);

         storeTypeTag(ImmTag(jv.s.tag), Operand(dest));

         storePayload(val, Operand(dest));

     }

     void storeValue(ValueOperand val, BaseIndex dest) {

         storeValue(val, Operand(dest));

     }

     void loadValue(Operand src, ValueOperand val) {

         Operand payload = ToPayload(src);

         Operand type = ToType(src);

         // Ensure that loading the payload does not erase the pointer to the

         // Value in memory or the index.

         Register baseReg = Register::FromCode(src.base());

         Register indexReg = (src.kind() == Operand::MEM_SCALE) ? Register::FromCode(src.index()) : InvalidReg;

         if (baseReg == val.payloadReg() || indexReg == val.payloadReg()) {

             JS_ASSERT(baseReg != val.typeReg());

             JS_ASSERT(indexReg != val.typeReg());

             movl(type, val.typeReg());

             movl(payload, val.payloadReg());

         } else {

             JS_ASSERT(baseReg != val.payloadReg());

             JS_ASSERT(indexReg != val.payloadReg());

             movl(payload, val.payloadReg());

             movl(type, val.typeReg());

         }

     }

     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) {

         JS_ASSERT(dest.typeReg() != dest.payloadReg());

         if (payload != dest.payloadReg())

             movl(payload, dest.payloadReg());

         movl(ImmType(type), dest.typeReg());

     }

     void pushValue(ValueOperand val) {

         push(val.typeReg());

         push(val.payloadReg());

     }

     void popValue(ValueOperand val) {

         pop(val.payloadReg());

         pop(val.typeReg());

     }

     void pushValue(const Value &val) {

         jsval_layout jv = JSVAL_TO_IMPL(val);

         push(Imm32(jv.s.tag));

         if (val.isMarkable())

             push(ImmGCPtr(reinterpret_cast<gc::Cell *>(val.toGCThing())));

         else

             push(Imm32(jv.s.payload.i32));

     }

     void pushValue(JSValueType type, Register reg) {

         push(ImmTag(JSVAL_TYPE_TO_TAG(type)));

         push(reg);

     }

     void pushValue(const Address &addr) {

         push(tagOf(addr));

         push(payloadOf(addr));

     }

     void Push(const ValueOperand &val) {

         pushValue(val);

         framePushed_ += sizeof(Value);

     }

     void Pop(const ValueOperand &val) {

         popValue(val);

         framePushed_ -= sizeof(Value);

     }

     void storePayload(const Value &val, Operand dest) {

         jsval_layout jv = JSVAL_TO_IMPL(val);

         if (val.isMarkable())

             movl(ImmGCPtr((gc::Cell *)jv.s.payload.ptr), ToPayload(dest));

         else

             movl(Imm32(jv.s.payload.i32), ToPayload(dest));

     }

     void storePayload(Register src, Operand dest) {

         movl(src, ToPayload(dest));

     }

     void storeTypeTag(ImmTag tag, Operand dest) {

         movl(tag, ToType(dest));

     }

     void movePtr(const Register &src, const Register &dest) {

         movl(src, dest);

     }

     void movePtr(const Register &src, const Operand &dest) {

         movl(src, dest);

     }

     // Returns the register containing the type tag.

     Register splitTagForTest(const ValueOperand &value) {

         return value.typeReg();

     }

     Condition testUndefined(Condition cond, const Register &tag) {

         JS_ASSERT(cond == Equal || cond == NotEqual);

         cmpl(tag, ImmTag(JSVAL_TAG_UNDEFINED));

         return cond;

     }

     Condition testBoolean(Condition cond, const Register &tag) {

         JS_ASSERT(cond == Equal || cond == NotEqual);

         cmpl(tag, ImmTag(JSVAL_TAG_BOOLEAN));

         return cond;

     }

     Condition testInt32(Condition cond, const Register &tag) {

         JS_ASSERT(cond == Equal || cond == NotEqual);

         cmpl(tag, ImmTag(JSVAL_TAG_INT32));

         return cond;

     }

     Condition testDouble(Condition cond, const Register &tag) {

         JS_ASSERT(cond == Assembler::Equal || cond == Assembler::NotEqual);

         Condition actual = (cond == Equal) ? Below : AboveOrEqual;

         cmpl(tag, ImmTag(JSVAL_TAG_CLEAR));

         return actual;

     }

     Condition testNull(Condition cond, const Register &tag) {

         JS_ASSERT(cond == Equal || cond == NotEqual);

         cmpl(tag, ImmTag(JSVAL_TAG_NULL));

         return cond;

     }

     Condition testString(Condition cond, const Register &tag) {

         JS_ASSERT(cond == Equal || cond == NotEqual);

         cmpl(tag, ImmTag(JSVAL_TAG_STRING));

         return cond;

     }

     Condition testObject(Condition cond, const Register &tag) {

         JS_ASSERT(cond == Equal || cond == NotEqual);

         cmpl(tag, ImmTag(JSVAL_TAG_OBJECT));

         return cond;

     }

     Condition testNumber(Condition cond, const Register &tag) {

         JS_ASSERT(cond == Equal || cond == NotEqual);

         cmpl(tag, ImmTag(JSVAL_UPPER_INCL_TAG_OF_NUMBER_SET));

         return cond == Equal ? BelowOrEqual : Above;

     }

     Condition testGCThing(Condition cond, const Register &tag) {

         JS_ASSERT(cond == Equal || cond == NotEqual);

         cmpl(tag, ImmTag(JSVAL_LOWER_INCL_TAG_OF_GCTHING_SET));

         return cond == Equal ? AboveOrEqual : Below;

     }

     Condition testGCThing(Condition cond, const Address &address) {

         JS_ASSERT(cond == Equal || cond == NotEqual);

         cmpl(tagOf(address), ImmTag(JSVAL_LOWER_INCL_TAG_OF_GCTHING_SET));

         return cond == Equal ? AboveOrEqual : Below;

     }

     Condition testMagic(Condition cond, const Address &address) {

         JS_ASSERT(cond == Equal || cond == NotEqual);

         cmpl(tagOf(address), ImmTag(JSVAL_TAG_MAGIC));

         return cond;

     }

     Condition testMagic(Condition cond, const Register &tag) {

         JS_ASSERT(cond == Equal || cond == NotEqual);

         cmpl(tag, ImmTag(JSVAL_TAG_MAGIC));

         return cond;

     }

     Condition testMagic(Condition cond, const Operand &operand) {

         JS_ASSERT(cond == Equal || cond == NotEqual);

         cmpl(ToType(operand), ImmTag(JSVAL_TAG_MAGIC));

         return cond;

     }

     Condition testPrimitive(Condition cond, const Register &tag) {

         JS_ASSERT(cond == Equal || cond == NotEqual);

         cmpl(tag, ImmTag(JSVAL_UPPER_EXCL_TAG_OF_PRIMITIVE_SET));

         return cond == Equal ? Below : AboveOrEqual;

     }

     Condition testError(Condition cond, const Register &tag) {

         return testMagic(cond, tag);

     }

     Condition testInt32(Condition cond, const Operand &operand) {

         JS_ASSERT(cond == Equal || cond == NotEqual);

         cmpl(ToType(operand), ImmTag(JSVAL_TAG_INT32));

         return cond;

     }

     Condition testInt32(Condition cond, const Address &address) {

         JS_ASSERT(cond == Equal || cond == NotEqual);

         return testInt32(cond, Operand(address));

     }

     Condition testDouble(Condition cond, const Operand &operand) {

         JS_ASSERT(cond == Equal || cond == NotEqual);

         Condition actual = (cond == Equal) ? Below : AboveOrEqual;

         cmpl(ToType(operand), ImmTag(JSVAL_TAG_CLEAR));

         return actual;

     }

     Condition testDouble(Condition cond, const Address &address) {

         JS_ASSERT(cond == Equal || cond == NotEqual);

         return testDouble(cond, Operand(address));

     }

     Condition testUndefined(Condition cond, const Operand &operand) {

         JS_ASSERT(cond == Equal || cond == NotEqual);

         cmpl(ToType(operand), ImmTag(JSVAL_TAG_UNDEFINED));

         return cond;

     }

     Condition testUndefined(Condition cond, const Address &addr) {

         return testUndefined(cond, Operand(addr));

     }

     Condition testUndefined(Condition cond, const ValueOperand &value) {

         return testUndefined(cond, value.typeReg());

     }

     Condition testBoolean(Condition cond, const ValueOperand &value) {

         return testBoolean(cond, value.typeReg());

     }

     Condition testInt32(Condition cond, const ValueOperand &value) {

         return testInt32(cond, value.typeReg());

     }

     Condition testDouble(Condition cond, const ValueOperand &value) {

         return testDouble(cond, value.typeReg());

     }

     Condition testNull(Condition cond, const ValueOperand &value) {

         return testNull(cond, value.typeReg());

     }

     Condition testString(Condition cond, const ValueOperand &value) {

         return testString(cond, value.typeReg());

     }

     Condition testObject(Condition cond, const ValueOperand &value) {

         return testObject(cond, value.typeReg());

     }

     Condition testMagic(Condition cond, const ValueOperand &value) {

         return testMagic(cond, value.typeReg());

     }

     Condition testError(Condition cond, const ValueOperand &value) {

         return testMagic(cond, value);

     }

     Condition testNumber(Condition cond, const ValueOperand &value) {

         return testNumber(cond, value.typeReg());

     }

     Condition testGCThing(Condition cond, const ValueOperand &value) {

         return testGCThing(cond, value.typeReg());

     }

     Condition testPrimitive(Condition cond, const ValueOperand &value) {

         return testPrimitive(cond, value.typeReg());

     }

     Condition testUndefined(Condition cond, const BaseIndex &address) {

         JS_ASSERT(cond == Equal || cond == NotEqual);

         cmpl(tagOf(address), ImmTag(JSVAL_TAG_UNDEFINED));

         return cond;

     }

     Condition testNull(Condition cond, const BaseIndex &address) {

         JS_ASSERT(cond == Equal || cond == NotEqual);

         cmpl(tagOf(address), ImmTag(JSVAL_TAG_NULL));

         return cond;

     }

     Condition testBoolean(Condition cond, const BaseIndex &address) {

         JS_ASSERT(cond == Equal || cond == NotEqual);

         cmpl(tagOf(address), ImmTag(JSVAL_TAG_BOOLEAN));

         return cond;

     }

     Condition testString(Condition cond, const BaseIndex &address) {

         JS_ASSERT(cond == Equal || cond == NotEqual);

         cmpl(tagOf(address), ImmTag(JSVAL_TAG_STRING));

         return cond;

     }

     Condition testInt32(Condition cond, const BaseIndex &address) {

         JS_ASSERT(cond == Equal || cond == NotEqual);

         cmpl(tagOf(address), ImmTag(JSVAL_TAG_INT32));

         return cond;

     }

     Condition testObject(Condition cond, const BaseIndex &address) {

         JS_ASSERT(cond == Equal || cond == NotEqual);

         cmpl(tagOf(address), ImmTag(JSVAL_TAG_OBJECT));

         return cond;

     }

     Condition testDouble(Condition cond, const BaseIndex &address) {

         JS_ASSERT(cond == Equal || cond == NotEqual);

         Condition actual = (cond == Equal) ? Below : AboveOrEqual;

         cmpl(tagOf(address), ImmTag(JSVAL_TAG_CLEAR));

         return actual;

     }

     Condition testMagic(Condition cond, const BaseIndex &address) {

         JS_ASSERT(cond == Equal || cond == NotEqual);

         cmpl(tagOf(address), ImmTag(JSVAL_TAG_MAGIC));

         return cond;

     }

     Condition testGCThing(Condition cond, const BaseIndex &address) {

         JS_ASSERT(cond == Equal || cond == NotEqual);

         cmpl(tagOf(address), ImmTag(JSVAL_LOWER_INCL_TAG_OF_GCTHING_SET));

         return cond == Equal ? AboveOrEqual : Below;

     }

     void branchTestValue(Condition cond, const ValueOperand &value, const Value &v, Label *label);

     void branchTestValue(Condition cond, const Address &valaddr, const ValueOperand &value,

                          Label *label)

     {

         JS_ASSERT(cond == Equal || cond == NotEqual);

         // Check payload before tag, since payload is more likely to differ.

         if (cond == NotEqual) {

             branchPtr(NotEqual, payloadOf(valaddr), value.payloadReg(), label);

             branchPtr(NotEqual, tagOf(valaddr), value.typeReg(), label);

         } else {

             Label fallthrough;

             branchPtr(NotEqual, payloadOf(valaddr), value.payloadReg(), &fallthrough);

             branchPtr(Equal, tagOf(valaddr), value.typeReg(), label);

             bind(&fallthrough);

         }

     }

     void testNullSet(Condition cond, const ValueOperand &value, Register dest) {

         cond = testNull(cond, value);

         emitSet(cond, dest);

     }

     void testUndefinedSet(Condition cond, const ValueOperand &value, Register dest) {

         cond = testUndefined(cond, value);

         emitSet(cond, dest);

     }

     void cmpPtr(Register lhs, const ImmWord rhs) {

         cmpl(lhs, Imm32(rhs.value));

     }

     void cmpPtr(Register lhs, const ImmPtr imm) {

         cmpPtr(lhs, ImmWord(uintptr_t(imm.value)));

     }

     void cmpPtr(Register lhs, const ImmGCPtr rhs) {

         cmpl(lhs, rhs);

     }

     void cmpPtr(Register lhs, const Imm32 rhs) {

         cmpl(lhs, rhs);

     }

     void cmpPtr(const Operand &lhs, const ImmWord rhs) {

         cmpl(lhs, rhs);

     }

     void cmpPtr(const Operand &lhs, const ImmPtr imm) {

         cmpPtr(lhs, ImmWord(uintptr_t(imm.value)));

     }

     void cmpPtr(const Operand &lhs, const ImmGCPtr rhs) {

         cmpl(lhs, rhs);

     }

     void cmpPtr(const Operand &lhs, const Imm32 rhs) {

         cmpl(lhs, rhs);

     }

     void cmpPtr(const Address &lhs, Register rhs) {

         cmpl(Operand(lhs), rhs);

     }

     void cmpPtr(const Address &lhs, const ImmWord rhs) {

         cmpl(Operand(lhs), rhs);

     }

     void cmpPtr(const Address &lhs, const ImmPtr rhs) {

         cmpPtr(lhs, ImmWord(uintptr_t(rhs.value)));

     }

     void cmpPtr(Register lhs, Register rhs) {

         cmpl(lhs, rhs);

     }

     void testPtr(Register lhs, Register rhs) {

         testl(lhs, rhs);

     }

     template <typename T1, typename T2>

     void cmpPtrSet(Assembler::Condition cond, T1 lhs, T2 rhs, const Register &dest)

     {

         cmpPtr(lhs, rhs);

         emitSet(cond, dest);

     }

     /////////////////////////////////////////////////////////////////

     // Common interface.

     /////////////////////////////////////////////////////////////////

     void reserveStack(uint32_t amount) {

         if (amount)

             subl(Imm32(amount), StackPointer);

         framePushed_ += amount;

     }

     void freeStack(uint32_t amount) {

         JS_ASSERT(amount <= framePushed_);

         if (amount)

             addl(Imm32(amount), StackPointer);

         framePushed_ -= amount;

     }

     void freeStack(Register amount) {

         addl(amount, StackPointer);

     }

     void addPtr(const Register &src, const Register &dest) {

         addl(src, dest);

     }

     void addPtr(Imm32 imm, const Register &dest) {

         addl(imm, dest);

     }

     void addPtr(ImmWord imm, const Register &dest) {

         addl(Imm32(imm.value), dest);

     }

     void addPtr(ImmPtr imm, const Register &dest) {

         addPtr(ImmWord(uintptr_t(imm.value)), dest);

     }

     void addPtr(Imm32 imm, const Address &dest) {

         addl(imm, Operand(dest));

     }

     void addPtr(Imm32 imm, const Operand &dest) {

         addl(imm, dest);

     }

     void addPtr(const Address &src, const Register &dest) {

         addl(Operand(src), dest);

     }

     void subPtr(Imm32 imm, const Register &dest) {

         subl(imm, dest);

     }

     void subPtr(const Register &src, const Register &dest) {

         subl(src, dest);

     }

     void subPtr(const Address &addr, const Register &dest) {

         subl(Operand(addr), dest);

     }

     void subPtr(const Register &src, const Address &dest) {

         subl(src, Operand(dest));

     }

     void branch32(Condition cond, const AbsoluteAddress &lhs, Imm32 rhs, Label *label) {

         cmpl(Operand(lhs), rhs);

         j(cond, label);

     }

     void branch32(Condition cond, const AbsoluteAddress &lhs, Register rhs, Label *label) {

         cmpl(Operand(lhs), rhs);

         j(cond, label);

     }

     // Specialization for AsmJSAbsoluteAddress.

     void branchPtr(Condition cond, AsmJSAbsoluteAddress lhs, Register ptr, Label *label) {

         cmpl(lhs, ptr);

         j(cond, label);

     }

     template <typename T, typename S>

     void branchPtr(Condition cond, T lhs, S ptr, Label *label) {

         cmpl(Operand(lhs), ptr);

         j(cond, label);

     }

     void branchPrivatePtr(Condition cond, const Address &lhs, ImmPtr ptr, Label *label) {

         branchPtr(cond, lhs, ptr, label);

     }

     void branchPrivatePtr(Condition cond, const Address &lhs, Register ptr, Label *label) {

         branchPtr(cond, lhs, ptr, label);

     }

     template <typename T, typename S>

     void branchPtr(Condition cond, T lhs, S ptr, RepatchLabel *label) {

         cmpl(Operand(lhs), ptr);

         j(cond, label);

     }

     CodeOffsetJump jumpWithPatch(RepatchLabel *label) {

         jump(label);

         return CodeOffsetJump(size());

     }

     CodeOffsetJump jumpWithPatch(RepatchLabel *label, Assembler::Condition cond) {

         j(cond, label);

         return CodeOffsetJump(size());

     }

     template <typename S, typename T>

     CodeOffsetJump branchPtrWithPatch(Condition cond, S lhs, T ptr, RepatchLabel *label) {

         branchPtr(cond, lhs, ptr, label);

         return CodeOffsetJump(size());

     }

     void branchPtr(Condition cond, Register lhs, Register rhs, RepatchLabel *label) {

         cmpl(lhs, rhs);

         j(cond, label);

     }

     void branchPtr(Condition cond, Register lhs, Register rhs, Label *label) {

         cmpl(lhs, rhs);

         j(cond, label);

     }

     void branchTestPtr(Condition cond, Register lhs, Register rhs, Label *label) {

         testl(lhs, rhs);

         j(cond, label);

     }

     void branchTestPtr(Condition cond, Register lhs, Imm32 imm, Label *label) {

         testl(lhs, imm);

         j(cond, label);

     }

     void branchTestPtr(Condition cond, const Address &lhs, Imm32 imm, Label *label) {

         testl(Operand(lhs), imm);

         j(cond, label);

     }

     void decBranchPtr(Condition cond, const Register &lhs, Imm32 imm, Label *label) {

         subPtr(imm, lhs);

         j(cond, label);

     }

     void movePtr(ImmWord imm, Register dest) {

         movl(Imm32(imm.value), dest);

     }

     void movePtr(ImmPtr imm, Register dest) {

         movl(imm, dest);

     }

     void movePtr(AsmJSImmPtr imm, Register dest) {

         mov(imm, dest);

     }

     void movePtr(ImmGCPtr imm, Register dest) {

         movl(imm, dest);

     }

     void loadPtr(const Address &address, Register dest) {

         movl(Operand(address), dest);

     }

     void loadPtr(const Operand &src, Register dest) {

         movl(src, dest);

     }

     void loadPtr(const BaseIndex &src, Register dest) {

         movl(Operand(src), dest);

     }

     void loadPtr(const AbsoluteAddress &address, Register dest) {

         movl(Operand(address), dest);

     }

     void loadPrivate(const Address &src, Register dest) {

         movl(payloadOf(src), dest);

     }

     void load32(const AbsoluteAddress &address, Register dest) {

         movl(Operand(address), dest);

     }

     void storePtr(ImmWord imm, const Address &address) {

         movl(Imm32(imm.value), Operand(address));

     }

     void storePtr(ImmPtr imm, const Address &address) {

         storePtr(ImmWord(uintptr_t(imm.value)), address);

     }

     void storePtr(ImmGCPtr imm, const Address &address) {

         movl(imm, Operand(address));

     }

     void storePtr(Register src, const Address &address) {

         movl(src, Operand(address));

     }

     void storePtr(Register src, const Operand &dest) {

         movl(src, dest);

     }

     void storePtr(Register src, const AbsoluteAddress &address) {

         movl(src, Operand(address));

     }

     void store32(Register src, const AbsoluteAddress &address) {

         movl(src, Operand(address));

     }

     void setStackArg(const Register &reg, uint32_t arg) {

         movl(reg, Operand(esp, arg * sizeof(intptr_t)));

     }

     // Type testing instructions can take a tag in a register or a

     // ValueOperand.

     template <typename T>

     void branchTestUndefined(Condition cond, const T &t, Label *label) {

         cond = testUndefined(cond, t);

         j(cond, label);

     }

     template <typename T>

     void branchTestInt32(Condition cond, const T &t, Label *label) {

         cond = testInt32(cond, t);

         j(cond, label);

     }

     template <typename T>

     void branchTestBoolean(Condition cond, const T &t, Label *label) {

         cond = testBoolean(cond, t);

         j(cond, label);

     }

     template <typename T>

     void branchTestDouble(Condition cond, const T &t, Label *label) {

         cond = testDouble(cond, t);

         j(cond, label);

     }

     template <typename T>

     void branchTestNull(Condition cond, const T &t, Label *label) {

         cond = testNull(cond, t);

         j(cond, label);

     }

     template <typename T>

     void branchTestString(Condition cond, const T &t, Label *label) {

         cond = testString(cond, t);

         j(cond, label);

     }

     template <typename T>

     void branchTestObject(Condition cond, const T &t, Label *label) {

         cond = testObject(cond, t);

         j(cond, label);

     }

     template <typename T>

     void branchTestNumber(Condition cond, const T &t, Label *label) {

         cond = testNumber(cond, t);

         j(cond, label);

     }

     template <typename T>

     void branchTestGCThing(Condition cond, const T &t, Label *label) {

         cond = testGCThing(cond, t);

         j(cond, label);

     }

     template <typename T>

     void branchTestPrimitive(Condition cond, const T &t, Label *label) {

         cond = testPrimitive(cond, t);

         j(cond, label);

     }

     template <typename T>

     void branchTestMagic(Condition cond, const T &t, Label *label) {

         cond = testMagic(cond, t);

         j(cond, label);

     }

     void branchTestMagicValue(Condition cond, const ValueOperand &val, JSWhyMagic why,

                               Label *label)

     {

         JS_ASSERT(cond == Equal || cond == NotEqual);

         if (cond == Equal) {

             // Test for magic

             Label notmagic;

             Condition testCond = testMagic(Equal, val);

             j(InvertCondition(testCond), &notmagic);

             // Test magic value

             branch32(Equal, val.payloadReg(), Imm32(static_cast<int32_t>(why)), label);

             bind(&notmagic);

         } else {

             Condition testCond = testMagic(NotEqual, val);

             j(testCond, label);

             branch32(NotEqual, val.payloadReg(), Imm32(static_cast<int32_t>(why)), label);

         }

     }

     // Note: this function clobbers the source register.

     void boxDouble(const FloatRegister &src, const ValueOperand &dest) {

         movd(src, dest.payloadReg());

         psrldq(Imm32(4), src);

         movd(src, dest.typeReg());

     }

     void boxNonDouble(JSValueType type, const Register &src, const ValueOperand &dest) {

         if (src != dest.payloadReg())

             movl(src, dest.payloadReg());

         movl(ImmType(type), dest.typeReg());

     }

     void unboxInt32(const ValueOperand &src, const Register &dest) {

         movl(src.payloadReg(), dest);

     }

     void unboxInt32(const Address &src, const Register &dest) {

         movl(payloadOf(src), dest);

     }

     void unboxDouble(const Address &src, const FloatRegister &dest) {

         loadDouble(Operand(src), dest);

     }

     void unboxBoolean(const ValueOperand &src, const Register &dest) {

         movl(src.payloadReg(), dest);

     }

     void unboxBoolean(const Address &src, const Register &dest) {

         movl(payloadOf(src), dest);

     }

     void unboxObject(const ValueOperand &src, const Register &dest) {

         if (src.payloadReg() != dest)

             movl(src.payloadReg(), dest);

     }

     void unboxDouble(const ValueOperand &src, const FloatRegister &dest) {

         JS_ASSERT(dest != ScratchFloatReg);

         if (Assembler::HasSSE41()) {

             movd(src.payloadReg(), dest);

             pinsrd(src.typeReg(), dest);

         } else {

             movd(src.payloadReg(), dest);

             movd(src.typeReg(), ScratchFloatReg);

             unpcklps(ScratchFloatReg, dest);

         }

     }

     void unboxDouble(const Operand &payload, const Operand &type,

                      const Register &scratch, const FloatRegister &dest) {

         JS_ASSERT(dest != ScratchFloatReg);

         if (Assembler::HasSSE41()) {

             movl(payload, scratch);

             movd(scratch, dest);

             movl(type, scratch);

             pinsrd(scratch, dest);

         } else {

             movl(payload, scratch);

             movd(scratch, dest);

             movl(type, scratch);

             movd(scratch, ScratchFloatReg);

             unpcklps(ScratchFloatReg, dest);

         }

     }

     void unboxString(const ValueOperand &src, const Register &dest) {

         movl(src.payloadReg(), dest);

     }

     void unboxString(const Address &src, const Register &dest) {

         movl(payloadOf(src), dest);

     }

     void unboxValue(const ValueOperand &src, AnyRegister dest) {

         if (dest.isFloat()) {

             Label notInt32, end;

             branchTestInt32(Assembler::NotEqual, src, &notInt32);

             convertInt32ToDouble(src.payloadReg(), dest.fpu());

             jump(&end);

             bind(&notInt32);

             unboxDouble(src, dest.fpu());

             bind(&end);

         } else {

             if (src.payloadReg() != dest.gpr())

                 movl(src.payloadReg(), dest.gpr());

         }

     }

     void unboxPrivate(const ValueOperand &src, Register dest) {

         if (src.payloadReg() != dest)

             movl(src.payloadReg(), dest);

     }

     void notBoolean(const ValueOperand &val) {

         xorl(Imm32(1), val.payloadReg());

     }

     // 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.

     Register extractObject(const Address &address, Register scratch) {

         movl(payloadOf(address), scratch);

         return scratch;

     }

     Register extractObject(const ValueOperand &value, Register scratch) {

         return value.payloadReg();

     }

     Register extractInt32(const ValueOperand &value, Register scratch) {

         return value.payloadReg();

     }

     Register extractBoolean(const ValueOperand &value, Register scratch) {

         return value.payloadReg();

     }

     Register extractTag(const Address &address, Register scratch) {

         movl(tagOf(address), scratch);

         return scratch;

     }

     Register extractTag(const ValueOperand &value, Register scratch) {

         return value.typeReg();

     }

     void boolValueToDouble(const ValueOperand &operand, const FloatRegister &dest) {

         convertInt32ToDouble(operand.payloadReg(), dest);

     }

     void boolValueToFloat32(const ValueOperand &operand, const FloatRegister &dest) {

         convertInt32ToFloat32(operand.payloadReg(), dest);

     }

     void int32ValueToDouble(const ValueOperand &operand, const FloatRegister &dest) {

         convertInt32ToDouble(operand.payloadReg(), dest);

     }

     void int32ValueToFloat32(const ValueOperand &operand, const FloatRegister &dest) {

         convertInt32ToFloat32(operand.payloadReg(), dest);

     }

     void loadConstantDouble(double d, const FloatRegister &dest);

     void addConstantDouble(double d, const FloatRegister &dest);

     void loadConstantFloat32(float f, const FloatRegister &dest);

     void addConstantFloat32(float f, const FloatRegister &dest);

     void branchTruncateDouble(const FloatRegister &src, const Register &dest, Label *fail) {

         cvttsd2si(src, dest);

         // cvttsd2si returns 0x80000000 on failure. Test for it by

         // subtracting 1 and testing overflow (this permits the use of a

         // smaller immediate field).

         cmpl(dest, Imm32(1));

         j(Assembler::Overflow, fail);

     }

     void branchTruncateFloat32(const FloatRegister &src, const Register &dest, Label *fail) {

         cvttss2si(src, dest);

         // cvttss2si returns 0x80000000 on failure. Test for it by

         // subtracting 1 and testing overflow (this permits the use of a

         // smaller immediate field).

         cmpl(dest, Imm32(1));

         j(Assembler::Overflow, fail);

     }

     Condition testInt32Truthy(bool truthy, const ValueOperand &operand) {

         testl(operand.payloadReg(), operand.payloadReg());

         return truthy ? NonZero : Zero;

     }

     void branchTestInt32Truthy(bool truthy, const ValueOperand &operand, Label *label) {

         Condition cond = testInt32Truthy(truthy, operand);

         j(cond, label);

     }

     void branchTestBooleanTruthy(bool truthy, const ValueOperand &operand, Label *label) {

         testl(operand.payloadReg(), operand.payloadReg());

         j(truthy ? NonZero : Zero, label);

     }

     Condition testStringTruthy(bool truthy, const ValueOperand &value) {

         Register string = value.payloadReg();

         Operand lengthAndFlags(string, JSString::offsetOfLengthAndFlags());

         size_t mask = (0xFFFFFFFF << JSString::LENGTH_SHIFT);

         testl(lengthAndFlags, Imm32(mask));

         return truthy ? Assembler::NonZero : Assembler::Zero;

     }

     void branchTestStringTruthy(bool truthy, const ValueOperand &value, Label *label) {

         Condition cond = testStringTruthy(truthy, value);

         j(cond, label);

     }

     void loadInt32OrDouble(const Operand &operand, const FloatRegister &dest) {

         Label notInt32, end;

         branchTestInt32(Assembler::NotEqual, operand, &notInt32);

         convertInt32ToDouble(ToPayload(operand), dest);

         jump(&end);

         bind(&notInt32);

         loadDouble(operand, dest);

         bind(&end);

     }

     template <typename T>

     void loadUnboxedValue(const T &src, MIRType type, AnyRegister dest) {

         if (dest.isFloat())

             loadInt32OrDouble(Operand(src), dest.fpu());

         else

             movl(Operand(src), dest.gpr());

     }

     void rshiftPtr(Imm32 imm, Register dest) {

         shrl(imm, dest);

     }

     void lshiftPtr(Imm32 imm, Register dest) {

         shll(imm, dest);

     }

     void xorPtr(Imm32 imm, Register dest) {

         xorl(imm, dest);

     }

     void xorPtr(Register src, Register dest) {

         xorl(src, dest);

     }

     void orPtr(Imm32 imm, Register dest) {

         orl(imm, dest);

     }

     void orPtr(Register src, Register dest) {

         orl(src, dest);

     }

     void andPtr(Imm32 imm, Register dest) {

         andl(imm, dest);

     }

     void andPtr(Register src, Register dest) {

         andl(src, dest);

     }

     void loadInstructionPointerAfterCall(const Register &dest) {

         movl(Operand(StackPointer, 0x0), dest);

     }

     // Note: this function clobbers the source register.

     void convertUInt32ToDouble(const Register &src, const FloatRegister &dest) {

         // src is [0, 2^32-1]

         subl(Imm32(0x80000000), src);

         // Now src is [-2^31, 2^31-1] - int range, but not the same value.

         convertInt32ToDouble(src, dest);

         // dest is now a double with the int range.

         // correct the double value by adding 0x80000000.

         addConstantDouble(2147483648.0, dest);

     }

     // Note: this function clobbers the source register.

     void convertUInt32ToFloat32(const Register &src, const FloatRegister &dest) {

         convertUInt32ToDouble(src, dest);

         convertDoubleToFloat32(dest, dest);

     }

     void inc64(AbsoluteAddress dest) {

         addl(Imm32(1), Operand(dest));

         Label noOverflow;

         j(NonZero, &noOverflow);

         addl(Imm32(1), Operand(dest.offset(4)));

         bind(&noOverflow);

     }

     // If source is a double, load it into dest. If source is int32,

     // convert it to double. Else, branch to failure.

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

         Label isDouble, done;

         branchTestDouble(Assembler::Equal, source.typeReg(), &isDouble);

         branchTestInt32(Assembler::NotEqual, source.typeReg(), failure);

         convertInt32ToDouble(source.payloadReg(), dest);

         jump(&done);

         bind(&isDouble);

         unboxDouble(source, dest);

         bind(&done);

     }

     // Setup a call to C/C++ code, given the number of general arguments it

     // takes. Note that this only supports cdecl.

     //

     // In order for alignment to work correctly, the MacroAssembler must have a

     // consistent view of the stack displacement. It is okay to call "push"

     // manually, however, if the stack alignment were to change, the macro

     // assembler should be notified before starting a call.

     void setupAlignedABICall(uint32_t args);

     // Sets up an ABI call for when the alignment is not known. This may need a

     // scratch register.

     void setupUnalignedABICall(uint32_t args, const Register &scratch);

     // Arguments must be assigned to a C/C++ call in order. They are moved

     // in parallel immediately before performing the call. This process may

     // temporarily use more stack, in which case esp-relative addresses will be

     // automatically adjusted. It is extremely important that esp-relative

     // addresses are computed *after* setupABICall(). Furthermore, no

     // operations should be emitted while setting arguments.

     void passABIArg(const MoveOperand &from, MoveOp::Type type);

     void passABIArg(const Register &reg);

     void passABIArg(const FloatRegister &reg, MoveOp::Type type);

   private:

     void callWithABIPre(uint32_t *stackAdjust);

     void callWithABIPost(uint32_t stackAdjust, MoveOp::Type result);

   public:

     // Emits a call to a C/C++ function, resolving all argument moves.

     void callWithABI(void *fun, MoveOp::Type result = MoveOp::GENERAL);

     void callWithABI(AsmJSImmPtr fun, MoveOp::Type result = MoveOp::GENERAL);

     void callWithABI(const Address &fun, MoveOp::Type result = MoveOp::GENERAL);

     // Used from within an Exit frame to handle a pending exception.

     void handleFailureWithHandler(void *handler);

     void handleFailureWithHandlerTail();

     void makeFrameDescriptor(Register frameSizeReg, FrameType type) {

         shll(Imm32(FRAMESIZE_SHIFT), frameSizeReg);

         orl(Imm32(type), frameSizeReg);

     }

     // Save an exit frame (which must be aligned to the stack pointer) to

     // ThreadData::ionTop of the main thread.

     void linkExitFrame() {

         movl(StackPointer, Operand(AbsoluteAddress(GetIonContext()->runtime->addressOfIonTop())));

     }

     void callWithExitFrame(JitCode *target, Register dynStack) {

         addPtr(Imm32(framePushed()), dynStack);

         makeFrameDescriptor(dynStack, JitFrame_IonJS);

         Push(dynStack);

         call(target);

     }

     void call(const CallSiteDesc &desc, AsmJSImmPtr target) {

         call(target);

         appendCallSite(desc);

     }

     void callExit(AsmJSImmPtr target, uint32_t stackArgBytes) {

         call(CallSiteDesc::Exit(), target);

     }

     // Save an exit frame to the thread data of the current thread, given a

     // register that holds a PerThreadData *.

     void linkParallelExitFrame(const Register &pt) {

         movl(StackPointer, Operand(pt, offsetof(PerThreadData, ionTop)));

     }

 #ifdef JSGC_GENERATIONAL

     void branchPtrInNurseryRange(Register ptr, Register temp, Label *label);

     void branchValueIsNurseryObject(ValueOperand value, Register temp, Label *label);

 #endif

 };

 typedef MacroAssemblerX86 MacroAssemblerSpecific;

 } // namespace jit

 } // namespace js

 #endif /* jit_x86_MacroAssembler_x86_h */