Add m-esr52 at 52.6.0

1 files changed, 2980 insertions, 0 deletions

diff --git a/js/src/jit/MacroAssembler.cpp b/js/src/jit/MacroAssembler.cpp
new file mode 100644
index 000000000..f633b9b7b
--- /dev/null
+++ b/js/src/jit/MacroAssembler.cpp
@@ -0,0 +1,2980 @@
+/* -*- 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/. */
+
+#include "jit/MacroAssembler-inl.h"
+
+#include "mozilla/CheckedInt.h"
+
+#include "jsfriendapi.h"
+#include "jsprf.h"
+
+#include "builtin/TypedObject.h"
+#include "gc/GCTrace.h"
+#include "jit/AtomicOp.h"
+#include "jit/Bailouts.h"
+#include "jit/BaselineFrame.h"
+#include "jit/BaselineIC.h"
+#include "jit/BaselineJIT.h"
+#include "jit/Lowering.h"
+#include "jit/MIR.h"
+#include "js/Conversions.h"
+#include "js/GCAPI.h"
+#include "vm/TraceLogging.h"
+
+#include "jsobjinlines.h"
+
+#include "gc/Nursery-inl.h"
+#include "jit/shared/Lowering-shared-inl.h"
+#include "vm/Interpreter-inl.h"
+
+using namespace js;
+using namespace js::jit;
+
+using JS::GenericNaN;
+using JS::ToInt32;
+
+using mozilla::CheckedUint32;
+
+template <typename Source> void
+MacroAssembler::guardTypeSet(const Source& address, const TypeSet* types, BarrierKind kind,
+                             Register scratch, Label* miss)
+{
+    MOZ_ASSERT(kind == BarrierKind::TypeTagOnly || kind == BarrierKind::TypeSet);
+    MOZ_ASSERT(!types->unknown());
+
+    Label matched;
+    TypeSet::Type tests[8] = {
+        TypeSet::Int32Type(),
+        TypeSet::UndefinedType(),
+        TypeSet::BooleanType(),
+        TypeSet::StringType(),
+        TypeSet::SymbolType(),
+        TypeSet::NullType(),
+        TypeSet::MagicArgType(),
+        TypeSet::AnyObjectType()
+    };
+
+    // The double type also implies Int32.
+    // So replace the int32 test with the double one.
+    if (types->hasType(TypeSet::DoubleType())) {
+        MOZ_ASSERT(types->hasType(TypeSet::Int32Type()));
+        tests[0] = TypeSet::DoubleType();
+    }
+
+    Register tag = extractTag(address, scratch);
+
+    // Emit all typed tests.
+    BranchType lastBranch;
+    for (size_t i = 0; i < mozilla::ArrayLength(tests); i++) {
+        if (!types->hasType(tests[i]))
+            continue;
+
+        if (lastBranch.isInitialized())
+            lastBranch.emit(*this);
+        lastBranch = BranchType(Equal, tag, tests[i], &matched);
+    }
+
+    // If this is the last check, invert the last branch.
+    if (types->hasType(TypeSet::AnyObjectType()) || !types->getObjectCount()) {
+        if (!lastBranch.isInitialized()) {
+            jump(miss);
+            return;
+        }
+
+        lastBranch.invertCondition();
+        lastBranch.relink(miss);
+        lastBranch.emit(*this);
+
+        bind(&matched);
+        return;
+    }
+
+    if (lastBranch.isInitialized())
+        lastBranch.emit(*this);
+
+    // Test specific objects.
+    MOZ_ASSERT(scratch != InvalidReg);
+    branchTestObject(NotEqual, tag, miss);
+    if (kind != BarrierKind::TypeTagOnly) {
+        Register obj = extractObject(address, scratch);
+        guardObjectType(obj, types, scratch, miss);
+    } else {
+#ifdef DEBUG
+        Label fail;
+        Register obj = extractObject(address, scratch);
+        guardObjectType(obj, types, scratch, &fail);
+        jump(&matched);
+        bind(&fail);
+
+        if (obj == scratch)
+            extractObject(address, scratch);
+        guardTypeSetMightBeIncomplete(types, obj, scratch, &matched);
+
+        assumeUnreachable("Unexpected object type");
+#endif
+    }
+
+    bind(&matched);
+}
+
+template <typename TypeSet>
+void
+MacroAssembler::guardTypeSetMightBeIncomplete(TypeSet* types, Register obj, Register scratch, Label* label)
+{
+    // Type set guards might miss when an object's group changes. In this case
+    // either its old group's properties will become unknown, or it will change
+    // to a native object with an original unboxed group. Jump to label if this
+    // might have happened for the input object.
+
+    if (types->unknownObject()) {
+        jump(label);
+        return;
+    }
+
+    loadPtr(Address(obj, JSObject::offsetOfGroup()), scratch);
+    load32(Address(scratch, ObjectGroup::offsetOfFlags()), scratch);
+    and32(Imm32(OBJECT_FLAG_ADDENDUM_MASK), scratch);
+    branch32(Assembler::Equal,
+             scratch, Imm32(ObjectGroup::addendumOriginalUnboxedGroupValue()), label);
+
+    for (size_t i = 0; i < types->getObjectCount(); i++) {
+        if (JSObject* singleton = types->getSingletonNoBarrier(i)) {
+            movePtr(ImmGCPtr(singleton), scratch);
+            loadPtr(Address(scratch, JSObject::offsetOfGroup()), scratch);
+        } else if (ObjectGroup* group = types->getGroupNoBarrier(i)) {
+            movePtr(ImmGCPtr(group), scratch);
+        } else {
+            continue;
+        }
+        branchTest32(Assembler::NonZero, Address(scratch, ObjectGroup::offsetOfFlags()),
+                     Imm32(OBJECT_FLAG_UNKNOWN_PROPERTIES), label);
+    }
+}
+
+void
+MacroAssembler::guardObjectType(Register obj, const TypeSet* types,
+                                Register scratch, Label* miss)
+{
+    MOZ_ASSERT(!types->unknown());
+    MOZ_ASSERT(!types->hasType(TypeSet::AnyObjectType()));
+    MOZ_ASSERT_IF(types->getObjectCount() > 0, scratch != InvalidReg);
+
+    // Note: this method elides read barriers on values read from type sets, as
+    // this may be called off the main thread during Ion compilation. This is
+    // safe to do as the final JitCode object will be allocated during the
+    // incremental GC (or the compilation canceled before we start sweeping),
+    // see CodeGenerator::link. Other callers should use TypeSet::readBarrier
+    // to trigger the barrier on the contents of type sets passed in here.
+    Label matched;
+
+    BranchGCPtr lastBranch;
+    MOZ_ASSERT(!lastBranch.isInitialized());
+    bool hasObjectGroups = false;
+    unsigned count = types->getObjectCount();
+    for (unsigned i = 0; i < count; i++) {
+        if (!types->getSingletonNoBarrier(i)) {
+            hasObjectGroups = hasObjectGroups || types->getGroupNoBarrier(i);
+            continue;
+        }
+
+        if (lastBranch.isInitialized()) {
+            comment("emit GC pointer checks");
+            lastBranch.emit(*this);
+        }
+
+        JSObject* object = types->getSingletonNoBarrier(i);
+        lastBranch = BranchGCPtr(Equal, obj, ImmGCPtr(object), &matched);
+    }
+
+    if (hasObjectGroups) {
+        comment("has object groups");
+        // We are possibly going to overwrite the obj register. So already
+        // emit the branch, since branch depends on previous value of obj
+        // register and there is definitely a branch following. So no need
+        // to invert the condition.
+        if (lastBranch.isInitialized())
+            lastBranch.emit(*this);
+        lastBranch = BranchGCPtr();
+
+        // Note: Some platforms give the same register for obj and scratch.
+        // Make sure when writing to scratch, the obj register isn't used anymore!
+        loadPtr(Address(obj, JSObject::offsetOfGroup()), scratch);
+
+        for (unsigned i = 0; i < count; i++) {
+            if (!types->getGroupNoBarrier(i))
+                continue;
+
+            if (lastBranch.isInitialized())
+                lastBranch.emit(*this);
+
+            ObjectGroup* group = types->getGroupNoBarrier(i);
+            lastBranch = BranchGCPtr(Equal, scratch, ImmGCPtr(group), &matched);
+        }
+    }
+
+    if (!lastBranch.isInitialized()) {
+        jump(miss);
+        return;
+    }
+
+    lastBranch.invertCondition();
+    lastBranch.relink(miss);
+    lastBranch.emit(*this);
+
+    bind(&matched);
+}
+
+template void MacroAssembler::guardTypeSet(const Address& address, const TypeSet* types,
+                                           BarrierKind kind, Register scratch, Label* miss);
+template void MacroAssembler::guardTypeSet(const ValueOperand& value, const TypeSet* types,
+                                           BarrierKind kind, Register scratch, Label* miss);
+template void MacroAssembler::guardTypeSet(const TypedOrValueRegister& value, const TypeSet* types,
+                                           BarrierKind kind, Register scratch, Label* miss);
+
+template void MacroAssembler::guardTypeSetMightBeIncomplete(const TemporaryTypeSet* types,
+                                                            Register obj, Register scratch,
+                                                            Label* label);
+
+template<typename S, typename T>
+static void
+StoreToTypedFloatArray(MacroAssembler& masm, int arrayType, const S& value, const T& dest,
+                       unsigned numElems)
+{
+    switch (arrayType) {
+      case Scalar::Float32:
+        masm.storeFloat32(value, dest);
+        break;
+      case Scalar::Float64:
+        masm.storeDouble(value, dest);
+        break;
+      case Scalar::Float32x4:
+        switch (numElems) {
+          case 1:
+            masm.storeFloat32(value, dest);
+            break;
+          case 2:
+            masm.storeDouble(value, dest);
+            break;
+          case 3:
+            masm.storeFloat32x3(value, dest);
+            break;
+          case 4:
+            masm.storeUnalignedSimd128Float(value, dest);
+            break;
+          default: MOZ_CRASH("unexpected number of elements in simd write");
+        }
+        break;
+      case Scalar::Int32x4:
+        switch (numElems) {
+          case 1:
+            masm.storeInt32x1(value, dest);
+            break;
+          case 2:
+            masm.storeInt32x2(value, dest);
+            break;
+          case 3:
+            masm.storeInt32x3(value, dest);
+            break;
+          case 4:
+            masm.storeUnalignedSimd128Int(value, dest);
+            break;
+          default: MOZ_CRASH("unexpected number of elements in simd write");
+        }
+        break;
+      case Scalar::Int8x16:
+        MOZ_ASSERT(numElems == 16, "unexpected partial store");
+        masm.storeUnalignedSimd128Int(value, dest);
+        break;
+      case Scalar::Int16x8:
+        MOZ_ASSERT(numElems == 8, "unexpected partial store");
+        masm.storeUnalignedSimd128Int(value, dest);
+        break;
+      default:
+        MOZ_CRASH("Invalid typed array type");
+    }
+}
+
+void
+MacroAssembler::storeToTypedFloatArray(Scalar::Type arrayType, FloatRegister value,
+                                       const BaseIndex& dest, unsigned numElems)
+{
+    StoreToTypedFloatArray(*this, arrayType, value, dest, numElems);
+}
+void
+MacroAssembler::storeToTypedFloatArray(Scalar::Type arrayType, FloatRegister value,
+                                       const Address& dest, unsigned numElems)
+{
+    StoreToTypedFloatArray(*this, arrayType, value, dest, numElems);
+}
+
+template<typename T>
+void
+MacroAssembler::loadFromTypedArray(Scalar::Type arrayType, const T& src, AnyRegister dest, Register temp,
+                                   Label* fail, bool canonicalizeDoubles, unsigned numElems)
+{
+    switch (arrayType) {
+      case Scalar::Int8:
+        load8SignExtend(src, dest.gpr());
+        break;
+      case Scalar::Uint8:
+      case Scalar::Uint8Clamped:
+        load8ZeroExtend(src, dest.gpr());
+        break;
+      case Scalar::Int16:
+        load16SignExtend(src, dest.gpr());
+        break;
+      case Scalar::Uint16:
+        load16ZeroExtend(src, dest.gpr());
+        break;
+      case Scalar::Int32:
+        load32(src, dest.gpr());
+        break;
+      case Scalar::Uint32:
+        if (dest.isFloat()) {
+            load32(src, temp);
+            convertUInt32ToDouble(temp, dest.fpu());
+        } else {
+            load32(src, dest.gpr());
+
+            // Bail out if the value doesn't fit into a signed int32 value. This
+            // is what allows MLoadUnboxedScalar to have a type() of
+            // MIRType::Int32 for UInt32 array loads.
+            branchTest32(Assembler::Signed, dest.gpr(), dest.gpr(), fail);
+        }
+        break;
+      case Scalar::Float32:
+        loadFloat32(src, dest.fpu());
+        canonicalizeFloat(dest.fpu());
+        break;
+      case Scalar::Float64:
+        loadDouble(src, dest.fpu());
+        if (canonicalizeDoubles)
+            canonicalizeDouble(dest.fpu());
+        break;
+      case Scalar::Int32x4:
+        switch (numElems) {
+          case 1:
+            loadInt32x1(src, dest.fpu());
+            break;
+          case 2:
+            loadInt32x2(src, dest.fpu());
+            break;
+          case 3:
+            loadInt32x3(src, dest.fpu());
+            break;
+          case 4:
+            loadUnalignedSimd128Int(src, dest.fpu());
+            break;
+          default: MOZ_CRASH("unexpected number of elements in SIMD load");
+        }
+        break;
+      case Scalar::Float32x4:
+        switch (numElems) {
+          case 1:
+            loadFloat32(src, dest.fpu());
+            break;
+          case 2:
+            loadDouble(src, dest.fpu());
+            break;
+          case 3:
+            loadFloat32x3(src, dest.fpu());
+            break;
+          case 4:
+            loadUnalignedSimd128Float(src, dest.fpu());
+            break;
+          default: MOZ_CRASH("unexpected number of elements in SIMD load");
+        }
+        break;
+      case Scalar::Int8x16:
+        MOZ_ASSERT(numElems == 16, "unexpected partial load");
+        loadUnalignedSimd128Int(src, dest.fpu());
+        break;
+      case Scalar::Int16x8:
+        MOZ_ASSERT(numElems == 8, "unexpected partial load");
+        loadUnalignedSimd128Int(src, dest.fpu());
+        break;
+      default:
+        MOZ_CRASH("Invalid typed array type");
+    }
+}
+
+template void MacroAssembler::loadFromTypedArray(Scalar::Type arrayType, const Address& src, AnyRegister dest,
+                                                 Register temp, Label* fail, bool canonicalizeDoubles,
+                                                 unsigned numElems);
+template void MacroAssembler::loadFromTypedArray(Scalar::Type arrayType, const BaseIndex& src, AnyRegister dest,
+                                                 Register temp, Label* fail, bool canonicalizeDoubles,
+                                                 unsigned numElems);
+
+template<typename T>
+void
+MacroAssembler::loadFromTypedArray(Scalar::Type arrayType, const T& src, const ValueOperand& dest,
+                                   bool allowDouble, Register temp, Label* fail)
+{
+    switch (arrayType) {
+      case Scalar::Int8:
+      case Scalar::Uint8:
+      case Scalar::Uint8Clamped:
+      case Scalar::Int16:
+      case Scalar::Uint16:
+      case Scalar::Int32:
+        loadFromTypedArray(arrayType, src, AnyRegister(dest.scratchReg()), InvalidReg, nullptr);
+        tagValue(JSVAL_TYPE_INT32, dest.scratchReg(), dest);
+        break;
+      case Scalar::Uint32:
+        // Don't clobber dest when we could fail, instead use temp.
+        load32(src, temp);
+        if (allowDouble) {
+            // If the value fits in an int32, store an int32 type tag.
+            // Else, convert the value to double and box it.
+            Label done, isDouble;
+            branchTest32(Assembler::Signed, temp, temp, &isDouble);
+            {
+                tagValue(JSVAL_TYPE_INT32, temp, dest);
+                jump(&done);
+            }
+            bind(&isDouble);
+            {
+                convertUInt32ToDouble(temp, ScratchDoubleReg);
+                boxDouble(ScratchDoubleReg, dest);
+            }
+            bind(&done);
+        } else {
+            // Bailout if the value does not fit in an int32.
+            branchTest32(Assembler::Signed, temp, temp, fail);
+            tagValue(JSVAL_TYPE_INT32, temp, dest);
+        }
+        break;
+      case Scalar::Float32:
+        loadFromTypedArray(arrayType, src, AnyRegister(ScratchFloat32Reg), dest.scratchReg(),
+                           nullptr);
+        convertFloat32ToDouble(ScratchFloat32Reg, ScratchDoubleReg);
+        boxDouble(ScratchDoubleReg, dest);
+        break;
+      case Scalar::Float64:
+        loadFromTypedArray(arrayType, src, AnyRegister(ScratchDoubleReg), dest.scratchReg(),
+                           nullptr);
+        boxDouble(ScratchDoubleReg, dest);
+        break;
+      default:
+        MOZ_CRASH("Invalid typed array type");
+    }
+}
+
+template void MacroAssembler::loadFromTypedArray(Scalar::Type arrayType, const Address& src, const ValueOperand& dest,
+                                                 bool allowDouble, Register temp, Label* fail);
+template void MacroAssembler::loadFromTypedArray(Scalar::Type arrayType, const BaseIndex& src, const ValueOperand& dest,
+                                                 bool allowDouble, Register temp, Label* fail);
+
+template <typename T>
+void
+MacroAssembler::loadUnboxedProperty(T address, JSValueType type, TypedOrValueRegister output)
+{
+    switch (type) {
+      case JSVAL_TYPE_INT32: {
+          // Handle loading an int32 into a double reg.
+          if (output.type() == MIRType::Double) {
+              convertInt32ToDouble(address, output.typedReg().fpu());
+              break;
+          }
+          MOZ_FALLTHROUGH;
+      }
+
+      case JSVAL_TYPE_BOOLEAN:
+      case JSVAL_TYPE_STRING: {
+        Register outReg;
+        if (output.hasValue()) {
+            outReg = output.valueReg().scratchReg();
+        } else {
+            MOZ_ASSERT(output.type() == MIRTypeFromValueType(type));
+            outReg = output.typedReg().gpr();
+        }
+
+        switch (type) {
+          case JSVAL_TYPE_BOOLEAN:
+            load8ZeroExtend(address, outReg);
+            break;
+          case JSVAL_TYPE_INT32:
+            load32(address, outReg);
+            break;
+          case JSVAL_TYPE_STRING:
+            loadPtr(address, outReg);
+            break;
+          default:
+            MOZ_CRASH();
+        }
+
+        if (output.hasValue())
+            tagValue(type, outReg, output.valueReg());
+        break;
+      }
+
+      case JSVAL_TYPE_OBJECT:
+        if (output.hasValue()) {
+            Register scratch = output.valueReg().scratchReg();
+            loadPtr(address, scratch);
+
+            Label notNull, done;
+            branchPtr(Assembler::NotEqual, scratch, ImmWord(0), &notNull);
+
+            moveValue(NullValue(), output.valueReg());
+            jump(&done);
+
+            bind(&notNull);
+            tagValue(JSVAL_TYPE_OBJECT, scratch, output.valueReg());
+
+            bind(&done);
+        } else {
+            // Reading null can't be possible here, as otherwise the result
+            // would be a value (either because null has been read before or
+            // because there is a barrier).
+            Register reg = output.typedReg().gpr();
+            loadPtr(address, reg);
+#ifdef DEBUG
+            Label ok;
+            branchTestPtr(Assembler::NonZero, reg, reg, &ok);
+            assumeUnreachable("Null not possible");
+            bind(&ok);
+#endif
+        }
+        break;
+
+      case JSVAL_TYPE_DOUBLE:
+        // Note: doubles in unboxed objects are not accessed through other
+        // views and do not need canonicalization.
+        if (output.hasValue())
+            loadValue(address, output.valueReg());
+        else
+            loadDouble(address, output.typedReg().fpu());
+        break;
+
+      default:
+        MOZ_CRASH();
+    }
+}
+
+template void
+MacroAssembler::loadUnboxedProperty(Address address, JSValueType type,
+                                    TypedOrValueRegister output);
+
+template void
+MacroAssembler::loadUnboxedProperty(BaseIndex address, JSValueType type,
+                                    TypedOrValueRegister output);
+
+static void
+StoreUnboxedFailure(MacroAssembler& masm, Label* failure)
+{
+    // Storing a value to an unboxed property is a fallible operation and
+    // the caller must provide a failure label if a particular unboxed store
+    // might fail. Sometimes, however, a store that cannot succeed (such as
+    // storing a string to an int32 property) will be marked as infallible.
+    // This can only happen if the code involved is unreachable.
+    if (failure)
+        masm.jump(failure);
+    else
+        masm.assumeUnreachable("Incompatible write to unboxed property");
+}
+
+template <typename T>
+void
+MacroAssembler::storeUnboxedProperty(T address, JSValueType type,
+                                     const ConstantOrRegister& value, Label* failure)
+{
+    switch (type) {
+      case JSVAL_TYPE_BOOLEAN:
+        if (value.constant()) {
+            if (value.value().isBoolean())
+                store8(Imm32(value.value().toBoolean()), address);
+            else
+                StoreUnboxedFailure(*this, failure);
+        } else if (value.reg().hasTyped()) {
+            if (value.reg().type() == MIRType::Boolean)
+                store8(value.reg().typedReg().gpr(), address);
+            else
+                StoreUnboxedFailure(*this, failure);
+        } else {
+            if (failure)
+                branchTestBoolean(Assembler::NotEqual, value.reg().valueReg(), failure);
+            storeUnboxedPayload(value.reg().valueReg(), address, /* width = */ 1);
+        }
+        break;
+
+      case JSVAL_TYPE_INT32:
+        if (value.constant()) {
+            if (value.value().isInt32())
+                store32(Imm32(value.value().toInt32()), address);
+            else
+                StoreUnboxedFailure(*this, failure);
+        } else if (value.reg().hasTyped()) {
+            if (value.reg().type() == MIRType::Int32)
+                store32(value.reg().typedReg().gpr(), address);
+            else
+                StoreUnboxedFailure(*this, failure);
+        } else {
+            if (failure)
+                branchTestInt32(Assembler::NotEqual, value.reg().valueReg(), failure);
+            storeUnboxedPayload(value.reg().valueReg(), address, /* width = */ 4);
+        }
+        break;
+
+      case JSVAL_TYPE_DOUBLE:
+        if (value.constant()) {
+            if (value.value().isNumber()) {
+                loadConstantDouble(value.value().toNumber(), ScratchDoubleReg);
+                storeDouble(ScratchDoubleReg, address);
+            } else {
+                StoreUnboxedFailure(*this, failure);
+            }
+        } else if (value.reg().hasTyped()) {
+            if (value.reg().type() == MIRType::Int32) {
+                convertInt32ToDouble(value.reg().typedReg().gpr(), ScratchDoubleReg);
+                storeDouble(ScratchDoubleReg, address);
+            } else if (value.reg().type() == MIRType::Double) {
+                storeDouble(value.reg().typedReg().fpu(), address);
+            } else {
+                StoreUnboxedFailure(*this, failure);
+            }
+        } else {
+            ValueOperand reg = value.reg().valueReg();
+            Label notInt32, end;
+            branchTestInt32(Assembler::NotEqual, reg, &notInt32);
+            int32ValueToDouble(reg, ScratchDoubleReg);
+            storeDouble(ScratchDoubleReg, address);
+            jump(&end);
+            bind(&notInt32);
+            if (failure)
+                branchTestDouble(Assembler::NotEqual, reg, failure);
+            storeValue(reg, address);
+            bind(&end);
+        }
+        break;
+
+      case JSVAL_TYPE_OBJECT:
+        if (value.constant()) {
+            if (value.value().isObjectOrNull())
+                storePtr(ImmGCPtr(value.value().toObjectOrNull()), address);
+            else
+                StoreUnboxedFailure(*this, failure);
+        } else if (value.reg().hasTyped()) {
+            MOZ_ASSERT(value.reg().type() != MIRType::Null);
+            if (value.reg().type() == MIRType::Object)
+                storePtr(value.reg().typedReg().gpr(), address);
+            else
+                StoreUnboxedFailure(*this, failure);
+        } else {
+            if (failure) {
+                Label ok;
+                branchTestNull(Assembler::Equal, value.reg().valueReg(), &ok);
+                branchTestObject(Assembler::NotEqual, value.reg().valueReg(), failure);
+                bind(&ok);
+            }
+            storeUnboxedPayload(value.reg().valueReg(), address, /* width = */ sizeof(uintptr_t));
+        }
+        break;
+
+      case JSVAL_TYPE_STRING:
+        if (value.constant()) {
+            if (value.value().isString())
+                storePtr(ImmGCPtr(value.value().toString()), address);
+            else
+                StoreUnboxedFailure(*this, failure);
+        } else if (value.reg().hasTyped()) {
+            if (value.reg().type() == MIRType::String)
+                storePtr(value.reg().typedReg().gpr(), address);
+            else
+                StoreUnboxedFailure(*this, failure);
+        } else {
+            if (failure)
+                branchTestString(Assembler::NotEqual, value.reg().valueReg(), failure);
+            storeUnboxedPayload(value.reg().valueReg(), address, /* width = */ sizeof(uintptr_t));
+        }
+        break;
+
+      default:
+        MOZ_CRASH();
+    }
+}
+
+template void
+MacroAssembler::storeUnboxedProperty(Address address, JSValueType type,
+                                     const ConstantOrRegister& value, Label* failure);
+
+template void
+MacroAssembler::storeUnboxedProperty(BaseIndex address, JSValueType type,
+                                     const ConstantOrRegister& value, Label* failure);
+
+void
+MacroAssembler::checkUnboxedArrayCapacity(Register obj, const RegisterOrInt32Constant& index,
+                                          Register temp, Label* failure)
+{
+    Address initLengthAddr(obj, UnboxedArrayObject::offsetOfCapacityIndexAndInitializedLength());
+    Address lengthAddr(obj, UnboxedArrayObject::offsetOfLength());
+
+    Label capacityIsIndex, done;
+    load32(initLengthAddr, temp);
+    branchTest32(Assembler::NonZero, temp, Imm32(UnboxedArrayObject::CapacityMask), &capacityIsIndex);
+    branch32(Assembler::BelowOrEqual, lengthAddr, index, failure);
+    jump(&done);
+    bind(&capacityIsIndex);
+
+    // Do a partial shift so that we can get an absolute offset from the base
+    // of CapacityArray to use.
+    JS_STATIC_ASSERT(sizeof(UnboxedArrayObject::CapacityArray[0]) == 4);
+    rshiftPtr(Imm32(UnboxedArrayObject::CapacityShift - 2), temp);
+    and32(Imm32(~0x3), temp);
+
+    addPtr(ImmPtr(&UnboxedArrayObject::CapacityArray), temp);
+    branch32(Assembler::BelowOrEqual, Address(temp, 0), index, failure);
+    bind(&done);
+}
+
+// Inlined version of gc::CheckAllocatorState that checks the bare essentials
+// and bails for anything that cannot be handled with our jit allocators.
+void
+MacroAssembler::checkAllocatorState(Label* fail)
+{
+    // Don't execute the inline path if we are tracing allocations,
+    // or when the memory profiler is enabled.
+    if (js::gc::TraceEnabled() || MemProfiler::enabled())
+        jump(fail);
+
+#ifdef JS_GC_ZEAL
+    // Don't execute the inline path if gc zeal or tracing are active.
+    branch32(Assembler::NotEqual,
+             AbsoluteAddress(GetJitContext()->runtime->addressOfGCZealModeBits()), Imm32(0),
+             fail);
+#endif
+
+    // Don't execute the inline path if the compartment has an object metadata callback,
+    // as the metadata to use for the object may vary between executions of the op.
+    if (GetJitContext()->compartment->hasAllocationMetadataBuilder())
+        jump(fail);
+}
+
+// Inline version of ShouldNurseryAllocate.
+bool
+MacroAssembler::shouldNurseryAllocate(gc::AllocKind allocKind, gc::InitialHeap initialHeap)
+{
+    // Note that Ion elides barriers on writes to objects known to be in the
+    // nursery, so any allocation that can be made into the nursery must be made
+    // into the nursery, even if the nursery is disabled. At runtime these will
+    // take the out-of-line path, which is required to insert a barrier for the
+    // initializing writes.
+    return IsNurseryAllocable(allocKind) && initialHeap != gc::TenuredHeap;
+}
+
+// Inline version of Nursery::allocateObject. If the object has dynamic slots,
+// this fills in the slots_ pointer.
+void
+MacroAssembler::nurseryAllocate(Register result, Register temp, gc::AllocKind allocKind,
+                                size_t nDynamicSlots, gc::InitialHeap initialHeap, Label* fail)
+{
+    MOZ_ASSERT(IsNurseryAllocable(allocKind));
+    MOZ_ASSERT(initialHeap != gc::TenuredHeap);
+
+    // We still need to allocate in the nursery, per the comment in
+    // shouldNurseryAllocate; however, we need to insert into the
+    // mallocedBuffers set, so bail to do the nursery allocation in the
+    // interpreter.
+    if (nDynamicSlots >= Nursery::MaxNurseryBufferSize / sizeof(Value)) {
+        jump(fail);
+        return;
+    }
+
+    // No explicit check for nursery.isEnabled() is needed, as the comparison
+    // with the nursery's end will always fail in such cases.
+    const Nursery& nursery = GetJitContext()->runtime->gcNursery();
+    int thingSize = int(gc::Arena::thingSize(allocKind));
+    int totalSize = thingSize + nDynamicSlots * sizeof(HeapSlot);
+    MOZ_ASSERT(totalSize % gc::CellSize == 0);
+    loadPtr(AbsoluteAddress(nursery.addressOfPosition()), result);
+    computeEffectiveAddress(Address(result, totalSize), temp);
+    branchPtr(Assembler::Below, AbsoluteAddress(nursery.addressOfCurrentEnd()), temp, fail);
+    storePtr(temp, AbsoluteAddress(nursery.addressOfPosition()));
+
+    if (nDynamicSlots) {
+        computeEffectiveAddress(Address(result, thingSize), temp);
+        storePtr(temp, Address(result, NativeObject::offsetOfSlots()));
+    }
+}
+
+// Inlined version of FreeSpan::allocate. This does not fill in slots_.
+void
+MacroAssembler::freeListAllocate(Register result, Register temp, gc::AllocKind allocKind, Label* fail)
+{
+    CompileZone* zone = GetJitContext()->compartment->zone();
+    int thingSize = int(gc::Arena::thingSize(allocKind));
+
+    Label fallback;
+    Label success;
+
+    // Load the first and last offsets of |zone|'s free list for |allocKind|.
+    // If there is no room remaining in the span, fall back to get the next one.
+    loadPtr(AbsoluteAddress(zone->addressOfFreeList(allocKind)), temp);
+    load16ZeroExtend(Address(temp, js::gc::FreeSpan::offsetOfFirst()), result);
+    load16ZeroExtend(Address(temp, js::gc::FreeSpan::offsetOfLast()), temp);
+    branch32(Assembler::AboveOrEqual, result, temp, &fallback);
+
+    // Bump the offset for the next allocation.
+    add32(Imm32(thingSize), result);
+    loadPtr(AbsoluteAddress(zone->addressOfFreeList(allocKind)), temp);
+    store16(result, Address(temp, js::gc::FreeSpan::offsetOfFirst()));
+    sub32(Imm32(thingSize), result);
+    addPtr(temp, result); // Turn the offset into a pointer.
+    jump(&success);
+
+    bind(&fallback);
+    // If there are no free spans left, we bail to finish the allocation. The
+    // interpreter will call the GC allocator to set up a new arena to allocate
+    // from, after which we can resume allocating in the jit.
+    branchTest32(Assembler::Zero, result, result, fail);
+    loadPtr(AbsoluteAddress(zone->addressOfFreeList(allocKind)), temp);
+    addPtr(temp, result); // Turn the offset into a pointer.
+    Push(result);
+    // Update the free list to point to the next span (which may be empty).
+    load32(Address(result, 0), result);
+    store32(result, Address(temp, js::gc::FreeSpan::offsetOfFirst()));
+    Pop(result);
+
+    bind(&success);
+}
+
+void
+MacroAssembler::callMallocStub(size_t nbytes, Register result, Label* fail)
+{
+    // This register must match the one in JitRuntime::generateMallocStub.
+    const Register regNBytes = CallTempReg0;
+
+    MOZ_ASSERT(nbytes > 0);
+    MOZ_ASSERT(nbytes <= INT32_MAX);
+
+    if (regNBytes != result)
+        push(regNBytes);
+    move32(Imm32(nbytes), regNBytes);
+    call(GetJitContext()->runtime->jitRuntime()->mallocStub());
+    if (regNBytes != result) {
+        movePtr(regNBytes, result);
+        pop(regNBytes);
+    }
+    branchTest32(Assembler::Zero, result, result, fail);
+}
+
+void
+MacroAssembler::callFreeStub(Register slots)
+{
+    // This register must match the one in JitRuntime::generateFreeStub.
+    const Register regSlots = CallTempReg0;
+
+    push(regSlots);
+    movePtr(slots, regSlots);
+    call(GetJitContext()->runtime->jitRuntime()->freeStub());
+    pop(regSlots);
+}
+
+// Inlined equivalent of gc::AllocateObject, without failure case handling.
+void
+MacroAssembler::allocateObject(Register result, Register temp, gc::AllocKind allocKind,
+                               uint32_t nDynamicSlots, gc::InitialHeap initialHeap, Label* fail)
+{
+    MOZ_ASSERT(gc::IsObjectAllocKind(allocKind));
+
+    checkAllocatorState(fail);
+
+    if (shouldNurseryAllocate(allocKind, initialHeap))
+        return nurseryAllocate(result, temp, allocKind, nDynamicSlots, initialHeap, fail);
+
+    if (!nDynamicSlots)
+        return freeListAllocate(result, temp, allocKind, fail);
+
+    callMallocStub(nDynamicSlots * sizeof(GCPtrValue), temp, fail);
+
+    Label failAlloc;
+    Label success;
+
+    push(temp);
+    freeListAllocate(result, temp, allocKind, &failAlloc);
+
+    pop(temp);
+    storePtr(temp, Address(result, NativeObject::offsetOfSlots()));
+
+    jump(&success);
+
+    bind(&failAlloc);
+    pop(temp);
+    callFreeStub(temp);
+    jump(fail);
+
+    bind(&success);
+}
+
+void
+MacroAssembler::createGCObject(Register obj, Register temp, JSObject* templateObj,
+                               gc::InitialHeap initialHeap, Label* fail, bool initContents,
+                               bool convertDoubleElements)
+{
+    gc::AllocKind allocKind = templateObj->asTenured().getAllocKind();
+    MOZ_ASSERT(gc::IsObjectAllocKind(allocKind));
+
+    uint32_t nDynamicSlots = 0;
+    if (templateObj->isNative()) {
+        nDynamicSlots = templateObj->as<NativeObject>().numDynamicSlots();
+
+        // Arrays with copy on write elements do not need fixed space for an
+        // elements header. The template object, which owns the original
+        // elements, might have another allocation kind.
+        if (templateObj->as<NativeObject>().denseElementsAreCopyOnWrite())
+            allocKind = gc::AllocKind::OBJECT0_BACKGROUND;
+    }
+
+    allocateObject(obj, temp, allocKind, nDynamicSlots, initialHeap, fail);
+    initGCThing(obj, temp, templateObj, initContents, convertDoubleElements);
+}
+
+
+// Inlined equivalent of gc::AllocateNonObject, without failure case handling.
+// Non-object allocation does not need to worry about slots, so can take a
+// simpler path.
+void
+MacroAssembler::allocateNonObject(Register result, Register temp, gc::AllocKind allocKind, Label* fail)
+{
+    checkAllocatorState(fail);
+    freeListAllocate(result, temp, allocKind, fail);
+}
+
+void
+MacroAssembler::newGCString(Register result, Register temp, Label* fail)
+{
+    allocateNonObject(result, temp, js::gc::AllocKind::STRING, fail);
+}
+
+void
+MacroAssembler::newGCFatInlineString(Register result, Register temp, Label* fail)
+{
+    allocateNonObject(result, temp, js::gc::AllocKind::FAT_INLINE_STRING, fail);
+}
+
+void
+MacroAssembler::copySlotsFromTemplate(Register obj, const NativeObject* templateObj,
+                                      uint32_t start, uint32_t end)
+{
+    uint32_t nfixed = Min(templateObj->numFixedSlotsForCompilation(), end);
+    for (unsigned i = start; i < nfixed; i++)
+        storeValue(templateObj->getFixedSlot(i), Address(obj, NativeObject::getFixedSlotOffset(i)));
+}
+
+void
+MacroAssembler::fillSlotsWithConstantValue(Address base, Register temp,
+                                           uint32_t start, uint32_t end, const Value& v)
+{
+    MOZ_ASSERT(v.isUndefined() || IsUninitializedLexical(v));
+
+    if (start >= end)
+        return;
+
+#ifdef JS_NUNBOX32
+    // We only have a single spare register, so do the initialization as two
+    // strided writes of the tag and body.
+    Address addr = base;
+    move32(Imm32(v.toNunboxPayload()), temp);
+    for (unsigned i = start; i < end; ++i, addr.offset += sizeof(GCPtrValue))
+        store32(temp, ToPayload(addr));
+
+    addr = base;
+    move32(Imm32(v.toNunboxTag()), temp);
+    for (unsigned i = start; i < end; ++i, addr.offset += sizeof(GCPtrValue))
+        store32(temp, ToType(addr));
+#else
+    moveValue(v, temp);
+    for (uint32_t i = start; i < end; ++i, base.offset += sizeof(GCPtrValue))
+        storePtr(temp, base);
+#endif
+}
+
+void
+MacroAssembler::fillSlotsWithUndefined(Address base, Register temp, uint32_t start, uint32_t end)
+{
+    fillSlotsWithConstantValue(base, temp, start, end, UndefinedValue());
+}
+
+void
+MacroAssembler::fillSlotsWithUninitialized(Address base, Register temp, uint32_t start, uint32_t end)
+{
+    fillSlotsWithConstantValue(base, temp, start, end, MagicValue(JS_UNINITIALIZED_LEXICAL));
+}
+
+static void
+FindStartOfUninitializedAndUndefinedSlots(NativeObject* templateObj, uint32_t nslots,
+                                          uint32_t* startOfUninitialized,
+                                          uint32_t* startOfUndefined)
+{
+    MOZ_ASSERT(nslots == templateObj->lastProperty()->slotSpan(templateObj->getClass()));
+    MOZ_ASSERT(nslots > 0);
+
+    uint32_t first = nslots;
+    for (; first != 0; --first) {
+        if (templateObj->getSlot(first - 1) != UndefinedValue())
+            break;
+    }
+    *startOfUndefined = first;
+
+    if (first != 0 && IsUninitializedLexical(templateObj->getSlot(first - 1))) {
+        for (; first != 0; --first) {
+            if (!IsUninitializedLexical(templateObj->getSlot(first - 1)))
+                break;
+        }
+        *startOfUninitialized = first;
+    } else {
+        *startOfUninitialized = *startOfUndefined;
+    }
+}
+
+static void
+AllocateObjectBufferWithInit(JSContext* cx, TypedArrayObject* obj, int32_t count)
+{
+    JS::AutoCheckCannotGC nogc(cx);
+
+    obj->initPrivate(nullptr);
+
+    // Negative numbers or zero will bail out to the slow path, which in turn will raise
+    // an invalid argument exception or create a correct object with zero elements.
+    if (count <= 0 || uint32_t(count) >= INT32_MAX / obj->bytesPerElement()) {
+        obj->setFixedSlot(TypedArrayObject::LENGTH_SLOT, Int32Value(0));
+        return;
+    }
+
+    obj->setFixedSlot(TypedArrayObject::LENGTH_SLOT, Int32Value(count));
+    size_t nbytes;
+
+    switch (obj->type()) {
+#define CREATE_TYPED_ARRAY(T, N) \
+      case Scalar::N: \
+        MOZ_ALWAYS_TRUE(js::CalculateAllocSize<T>(count, &nbytes)); \
+        break;
+JS_FOR_EACH_TYPED_ARRAY(CREATE_TYPED_ARRAY)
+#undef CREATE_TYPED_ARRAY
+      default:
+        MOZ_CRASH("Unsupported TypedArray type");
+    }
+
+    MOZ_ASSERT((CheckedUint32(nbytes) + sizeof(Value)).isValid());
+
+    nbytes = JS_ROUNDUP(nbytes, sizeof(Value));
+    Nursery& nursery = cx->runtime()->gc.nursery;
+    void* buf = nursery.allocateBuffer(obj, nbytes);
+    if (buf) {
+        obj->initPrivate(buf);
+        memset(buf, 0, nbytes);
+    }
+}
+
+void
+MacroAssembler::initTypedArraySlots(Register obj, Register temp, Register lengthReg,
+                                    LiveRegisterSet liveRegs, Label* fail,
+                                    TypedArrayObject* templateObj, TypedArrayLength lengthKind)
+{
+    MOZ_ASSERT(templateObj->hasPrivate());
+    MOZ_ASSERT(!templateObj->hasBuffer());
+
+    size_t dataSlotOffset = TypedArrayObject::dataOffset();
+    size_t dataOffset = TypedArrayObject::dataOffset() + sizeof(HeapSlot);
+
+    static_assert(TypedArrayObject::FIXED_DATA_START == TypedArrayObject::DATA_SLOT + 1,
+                    "fixed inline element data assumed to begin after the data slot");
+
+    // Initialise data elements to zero.
+    int32_t length = templateObj->length();
+    size_t nbytes = length * templateObj->bytesPerElement();
+
+    if (lengthKind == TypedArrayLength::Fixed && dataOffset + nbytes <= JSObject::MAX_BYTE_SIZE) {
+        MOZ_ASSERT(dataOffset + nbytes <= templateObj->tenuredSizeOfThis());
+
+        // Store data elements inside the remaining JSObject slots.
+        computeEffectiveAddress(Address(obj, dataOffset), temp);
+        storePtr(temp, Address(obj, dataSlotOffset));
+
+        // Write enough zero pointers into fixed data to zero every
+        // element.  (This zeroes past the end of a byte count that's
+        // not a multiple of pointer size.  That's okay, because fixed
+        // data is a count of 8-byte HeapSlots (i.e. <= pointer size),
+        // and we won't inline unless the desired memory fits in that
+        // space.)
+        static_assert(sizeof(HeapSlot) == 8, "Assumed 8 bytes alignment");
+
+        size_t numZeroPointers = ((nbytes + 7) & ~0x7) / sizeof(char *);
+        for (size_t i = 0; i < numZeroPointers; i++)
+            storePtr(ImmWord(0), Address(obj, dataOffset + i * sizeof(char *)));
+#ifdef DEBUG
+        if (nbytes == 0)
+            store8(Imm32(TypedArrayObject::ZeroLengthArrayData), Address(obj, dataSlotOffset));
+#endif
+    } else {
+        if (lengthKind == TypedArrayLength::Fixed)
+            move32(Imm32(length), lengthReg);
+
+        // Allocate a buffer on the heap to store the data elements.
+        liveRegs.addUnchecked(temp);
+        liveRegs.addUnchecked(obj);
+        liveRegs.addUnchecked(lengthReg);
+        PushRegsInMask(liveRegs);
+        setupUnalignedABICall(temp);
+        loadJSContext(temp);
+        passABIArg(temp);
+        passABIArg(obj);
+        passABIArg(lengthReg);
+        callWithABI(JS_FUNC_TO_DATA_PTR(void*, AllocateObjectBufferWithInit));
+        PopRegsInMask(liveRegs);
+
+        // Fail when data elements is set to NULL.
+        branchPtr(Assembler::Equal, Address(obj, dataSlotOffset), ImmWord(0), fail);
+    }
+}
+
+void
+MacroAssembler::initGCSlots(Register obj, Register temp, NativeObject* templateObj,
+                            bool initContents)
+{
+    // Slots of non-array objects are required to be initialized.
+    // Use the values currently in the template object.
+    uint32_t nslots = templateObj->lastProperty()->slotSpan(templateObj->getClass());
+    if (nslots == 0)
+        return;
+
+    uint32_t nfixed = templateObj->numUsedFixedSlots();
+    uint32_t ndynamic = templateObj->numDynamicSlots();
+
+    // Attempt to group slot writes such that we minimize the amount of
+    // duplicated data we need to embed in code and load into registers. In
+    // general, most template object slots will be undefined except for any
+    // reserved slots. Since reserved slots come first, we split the object
+    // logically into independent non-UndefinedValue writes to the head and
+    // duplicated writes of UndefinedValue to the tail. For the majority of
+    // objects, the "tail" will be the entire slot range.
+    //
+    // The template object may be a CallObject, in which case we need to
+    // account for uninitialized lexical slots as well as undefined
+    // slots. Unitialized lexical slots appears in CallObjects if the function
+    // has parameter expressions, in which case closed over parameters have
+    // TDZ. Uninitialized slots come before undefined slots in CallObjects.
+    uint32_t startOfUninitialized = nslots;
+    uint32_t startOfUndefined = nslots;
+    FindStartOfUninitializedAndUndefinedSlots(templateObj, nslots,
+                                              &startOfUninitialized, &startOfUndefined);
+    MOZ_ASSERT(startOfUninitialized <= nfixed); // Reserved slots must be fixed.
+    MOZ_ASSERT(startOfUndefined >= startOfUninitialized);
+    MOZ_ASSERT_IF(!templateObj->is<CallObject>(), startOfUninitialized == startOfUndefined);
+
+    // Copy over any preserved reserved slots.
+    copySlotsFromTemplate(obj, templateObj, 0, startOfUninitialized);
+
+    // Fill the rest of the fixed slots with undefined and uninitialized.
+    if (initContents) {
+        size_t offset = NativeObject::getFixedSlotOffset(startOfUninitialized);
+        fillSlotsWithUninitialized(Address(obj, offset), temp,
+                                   startOfUninitialized, Min(startOfUndefined, nfixed));
+
+        offset = NativeObject::getFixedSlotOffset(startOfUndefined);
+        fillSlotsWithUndefined(Address(obj, offset), temp,
+                               startOfUndefined, nfixed);
+    }
+
+    if (ndynamic) {
+        // We are short one register to do this elegantly. Borrow the obj
+        // register briefly for our slots base address.
+        push(obj);
+        loadPtr(Address(obj, NativeObject::offsetOfSlots()), obj);
+
+        // Fill uninitialized slots if necessary. Otherwise initialize all
+        // slots to undefined.
+        if (startOfUndefined > nfixed) {
+            MOZ_ASSERT(startOfUninitialized != startOfUndefined);
+            fillSlotsWithUninitialized(Address(obj, 0), temp, 0, startOfUndefined - nfixed);
+            size_t offset = (startOfUndefined - nfixed) * sizeof(Value);
+            fillSlotsWithUndefined(Address(obj, offset), temp, startOfUndefined - nfixed, ndynamic);
+        } else {
+            fillSlotsWithUndefined(Address(obj, 0), temp, 0, ndynamic);
+        }
+
+        pop(obj);
+    }
+}
+
+void
+MacroAssembler::initGCThing(Register obj, Register temp, JSObject* templateObj,
+                            bool initContents, bool convertDoubleElements)
+{
+    // Fast initialization of an empty object returned by allocateObject().
+
+    storePtr(ImmGCPtr(templateObj->group()), Address(obj, JSObject::offsetOfGroup()));
+
+    if (Shape* shape = templateObj->maybeShape())
+        storePtr(ImmGCPtr(shape), Address(obj, ShapedObject::offsetOfShape()));
+
+    MOZ_ASSERT_IF(convertDoubleElements, templateObj->is<ArrayObject>());
+
+    if (templateObj->isNative()) {
+        NativeObject* ntemplate = &templateObj->as<NativeObject>();
+        MOZ_ASSERT_IF(!ntemplate->denseElementsAreCopyOnWrite(), !ntemplate->hasDynamicElements());
+
+        // If the object has dynamic slots, the slots member has already been
+        // filled in.
+        if (!ntemplate->hasDynamicSlots())
+            storePtr(ImmPtr(nullptr), Address(obj, NativeObject::offsetOfSlots()));
+
+        if (ntemplate->denseElementsAreCopyOnWrite()) {
+            storePtr(ImmPtr((const Value*) ntemplate->getDenseElements()),
+                     Address(obj, NativeObject::offsetOfElements()));
+        } else if (ntemplate->is<ArrayObject>()) {
+            int elementsOffset = NativeObject::offsetOfFixedElements();
+
+            computeEffectiveAddress(Address(obj, elementsOffset), temp);
+            storePtr(temp, Address(obj, NativeObject::offsetOfElements()));
+
+            // Fill in the elements header.
+            store32(Imm32(ntemplate->getDenseCapacity()),
+                    Address(obj, elementsOffset + ObjectElements::offsetOfCapacity()));
+            store32(Imm32(ntemplate->getDenseInitializedLength()),
+                    Address(obj, elementsOffset + ObjectElements::offsetOfInitializedLength()));
+            store32(Imm32(ntemplate->as<ArrayObject>().length()),
+                    Address(obj, elementsOffset + ObjectElements::offsetOfLength()));
+            store32(Imm32(convertDoubleElements
+                          ? ObjectElements::CONVERT_DOUBLE_ELEMENTS
+                          : 0),
+                    Address(obj, elementsOffset + ObjectElements::offsetOfFlags()));
+            MOZ_ASSERT(!ntemplate->hasPrivate());
+        } else if (ntemplate->is<ArgumentsObject>()) {
+            // The caller will initialize the reserved slots.
+            MOZ_ASSERT(!initContents);
+            MOZ_ASSERT(!ntemplate->hasPrivate());
+            storePtr(ImmPtr(emptyObjectElements), Address(obj, NativeObject::offsetOfElements()));
+        } else {
+            // If the target type could be a TypedArray that maps shared memory
+            // then this would need to store emptyObjectElementsShared in that case.
+            MOZ_ASSERT(!ntemplate->isSharedMemory());
+
+            storePtr(ImmPtr(emptyObjectElements), Address(obj, NativeObject::offsetOfElements()));
+
+            initGCSlots(obj, temp, ntemplate, initContents);
+
+            if (ntemplate->hasPrivate() && !ntemplate->is<TypedArrayObject>()) {
+                uint32_t nfixed = ntemplate->numFixedSlotsForCompilation();
+                storePtr(ImmPtr(ntemplate->getPrivate()),
+                         Address(obj, NativeObject::getPrivateDataOffset(nfixed)));
+            }
+        }
+    } else if (templateObj->is<InlineTypedObject>()) {
+        JS::AutoAssertNoGC nogc; // off-thread, so cannot GC
+        size_t nbytes = templateObj->as<InlineTypedObject>().size();
+        const uint8_t* memory = templateObj->as<InlineTypedObject>().inlineTypedMem(nogc);
+
+        // Memcpy the contents of the template object to the new object.
+        size_t offset = 0;
+        while (nbytes) {
+            uintptr_t value = *(uintptr_t*)(memory + offset);
+            storePtr(ImmWord(value),
+                     Address(obj, InlineTypedObject::offsetOfDataStart() + offset));
+            nbytes = (nbytes < sizeof(uintptr_t)) ? 0 : nbytes - sizeof(uintptr_t);
+            offset += sizeof(uintptr_t);
+        }
+    } else if (templateObj->is<UnboxedPlainObject>()) {
+        storePtr(ImmWord(0), Address(obj, UnboxedPlainObject::offsetOfExpando()));
+        if (initContents)
+            initUnboxedObjectContents(obj, &templateObj->as<UnboxedPlainObject>());
+    } else if (templateObj->is<UnboxedArrayObject>()) {
+        MOZ_ASSERT(templateObj->as<UnboxedArrayObject>().hasInlineElements());
+        int elementsOffset = UnboxedArrayObject::offsetOfInlineElements();
+        computeEffectiveAddress(Address(obj, elementsOffset), temp);
+        storePtr(temp, Address(obj, UnboxedArrayObject::offsetOfElements()));
+        store32(Imm32(templateObj->as<UnboxedArrayObject>().length()),
+                Address(obj, UnboxedArrayObject::offsetOfLength()));
+        uint32_t capacityIndex = templateObj->as<UnboxedArrayObject>().capacityIndex();
+        store32(Imm32(capacityIndex << UnboxedArrayObject::CapacityShift),
+                Address(obj, UnboxedArrayObject::offsetOfCapacityIndexAndInitializedLength()));
+    } else {
+        MOZ_CRASH("Unknown object");
+    }
+
+#ifdef JS_GC_TRACE
+    RegisterSet regs = RegisterSet::Volatile();
+    PushRegsInMask(regs);
+    regs.takeUnchecked(obj);
+    Register temp = regs.takeAnyGeneral();
+
+    setupUnalignedABICall(temp);
+    passABIArg(obj);
+    movePtr(ImmGCPtr(templateObj->type()), temp);
+    passABIArg(temp);
+    callWithABI(JS_FUNC_TO_DATA_PTR(void*, js::gc::TraceCreateObject));
+
+    PopRegsInMask(RegisterSet::Volatile());
+#endif
+}
+
+void
+MacroAssembler::initUnboxedObjectContents(Register object, UnboxedPlainObject* templateObject)
+{
+    const UnboxedLayout& layout = templateObject->layoutDontCheckGeneration();
+
+    // Initialize reference fields of the object, per UnboxedPlainObject::create.
+    if (const int32_t* list = layout.traceList()) {
+        while (*list != -1) {
+            storePtr(ImmGCPtr(GetJitContext()->runtime->names().empty),
+                     Address(object, UnboxedPlainObject::offsetOfData() + *list));
+            list++;
+        }
+        list++;
+        while (*list != -1) {
+            storePtr(ImmWord(0),
+                     Address(object, UnboxedPlainObject::offsetOfData() + *list));
+            list++;
+        }
+        // Unboxed objects don't have Values to initialize.
+        MOZ_ASSERT(*(list + 1) == -1);
+    }
+}
+
+void
+MacroAssembler::compareStrings(JSOp op, Register left, Register right, Register result,
+                               Label* fail)
+{
+    MOZ_ASSERT(IsEqualityOp(op));
+
+    Label done;
+    Label notPointerEqual;
+    // Fast path for identical strings.
+    branchPtr(Assembler::NotEqual, left, right, &notPointerEqual);
+    move32(Imm32(op == JSOP_EQ || op == JSOP_STRICTEQ), result);
+    jump(&done);
+
+    bind(&notPointerEqual);
+
+    Label notAtom;
+    // Optimize the equality operation to a pointer compare for two atoms.
+    Imm32 atomBit(JSString::ATOM_BIT);
+    branchTest32(Assembler::Zero, Address(left, JSString::offsetOfFlags()), atomBit, &notAtom);
+    branchTest32(Assembler::Zero, Address(right, JSString::offsetOfFlags()), atomBit, &notAtom);
+
+    cmpPtrSet(JSOpToCondition(MCompare::Compare_String, op), left, right, result);
+    jump(&done);
+
+    bind(&notAtom);
+    // Strings of different length can never be equal.
+    loadStringLength(left, result);
+    branch32(Assembler::Equal, Address(right, JSString::offsetOfLength()), result, fail);
+    move32(Imm32(op == JSOP_NE || op == JSOP_STRICTNE), result);
+
+    bind(&done);
+}
+
+void
+MacroAssembler::loadStringChars(Register str, Register dest)
+{
+    Label isInline, done;
+    branchTest32(Assembler::NonZero, Address(str, JSString::offsetOfFlags()),
+                 Imm32(JSString::INLINE_CHARS_BIT), &isInline);
+
+    loadPtr(Address(str, JSString::offsetOfNonInlineChars()), dest);
+    jump(&done);
+
+    bind(&isInline);
+    computeEffectiveAddress(Address(str, JSInlineString::offsetOfInlineStorage()), dest);
+
+    bind(&done);
+}
+
+void
+MacroAssembler::loadStringChar(Register str, Register index, Register output)
+{
+    MOZ_ASSERT(str != output);
+    MOZ_ASSERT(index != output);
+
+    loadStringChars(str, output);
+
+    Label isLatin1, done;
+    branchLatin1String(str, &isLatin1);
+    load16ZeroExtend(BaseIndex(output, index, TimesTwo), output);
+    jump(&done);
+
+    bind(&isLatin1);
+    load8ZeroExtend(BaseIndex(output, index, TimesOne), output);
+
+    bind(&done);
+}
+
+static void
+BailoutReportOverRecursed(JSContext* cx)
+{
+    ReportOverRecursed(cx);
+}
+
+void
+MacroAssembler::generateBailoutTail(Register scratch, Register bailoutInfo)
+{
+    enterExitFrame();
+
+    Label baseline;
+
+    // The return value from Bailout is tagged as:
+    // - 0x0: done (enter baseline)
+    // - 0x1: error (handle exception)
+    // - 0x2: overrecursed
+    JS_STATIC_ASSERT(BAILOUT_RETURN_OK == 0);
+    JS_STATIC_ASSERT(BAILOUT_RETURN_FATAL_ERROR == 1);
+    JS_STATIC_ASSERT(BAILOUT_RETURN_OVERRECURSED == 2);
+
+    branch32(Equal, ReturnReg, Imm32(BAILOUT_RETURN_OK), &baseline);
+    branch32(Equal, ReturnReg, Imm32(BAILOUT_RETURN_FATAL_ERROR), exceptionLabel());
+
+    // Fall-through: overrecursed.
+    {
+        loadJSContext(ReturnReg);
+        setupUnalignedABICall(scratch);
+        passABIArg(ReturnReg);
+        callWithABI(JS_FUNC_TO_DATA_PTR(void*, BailoutReportOverRecursed));
+        jump(exceptionLabel());
+    }
+
+    bind(&baseline);
+    {
+        // Prepare a register set for use in this case.
+        AllocatableGeneralRegisterSet regs(GeneralRegisterSet::All());
+        MOZ_ASSERT(!regs.has(getStackPointer()));
+        regs.take(bailoutInfo);
+
+        // Reset SP to the point where clobbering starts.
+        loadStackPtr(Address(bailoutInfo, offsetof(BaselineBailoutInfo, incomingStack)));
+
+        Register copyCur = regs.takeAny();
+        Register copyEnd = regs.takeAny();
+        Register temp = regs.takeAny();
+
+        // Copy data onto stack.
+        loadPtr(Address(bailoutInfo, offsetof(BaselineBailoutInfo, copyStackTop)), copyCur);
+        loadPtr(Address(bailoutInfo, offsetof(BaselineBailoutInfo, copyStackBottom)), copyEnd);
+        {
+            Label copyLoop;
+            Label endOfCopy;
+            bind(&copyLoop);
+            branchPtr(Assembler::BelowOrEqual, copyCur, copyEnd, &endOfCopy);
+            subPtr(Imm32(4), copyCur);
+            subFromStackPtr(Imm32(4));
+            load32(Address(copyCur, 0), temp);
+            store32(temp, Address(getStackPointer(), 0));
+            jump(&copyLoop);
+            bind(&endOfCopy);
+        }
+
+        // Enter exit frame for the FinishBailoutToBaseline call.
+        loadPtr(Address(bailoutInfo, offsetof(BaselineBailoutInfo, resumeFramePtr)), temp);
+        load32(Address(temp, BaselineFrame::reverseOffsetOfFrameSize()), temp);
+        makeFrameDescriptor(temp, JitFrame_BaselineJS, ExitFrameLayout::Size());
+        push(temp);
+        push(Address(bailoutInfo, offsetof(BaselineBailoutInfo, resumeAddr)));
+        // No GC things to mark on the stack, push a bare token.
+        enterFakeExitFrame(ExitFrameLayoutBareToken);
+
+        // If monitorStub is non-null, handle resumeAddr appropriately.
+        Label noMonitor;
+        Label done;
+        branchPtr(Assembler::Equal,
+                  Address(bailoutInfo, offsetof(BaselineBailoutInfo, monitorStub)),
+                  ImmPtr(nullptr),
+                  &noMonitor);
+
+        //
+        // Resuming into a monitoring stub chain.
+        //
+        {
+            // Save needed values onto stack temporarily.
+            pushValue(Address(bailoutInfo, offsetof(BaselineBailoutInfo, valueR0)));
+            push(Address(bailoutInfo, offsetof(BaselineBailoutInfo, resumeFramePtr)));
+            push(Address(bailoutInfo, offsetof(BaselineBailoutInfo, resumeAddr)));
+            push(Address(bailoutInfo, offsetof(BaselineBailoutInfo, monitorStub)));
+
+            // Call a stub to free allocated memory and create arguments objects.
+            setupUnalignedABICall(temp);
+            passABIArg(bailoutInfo);
+            callWithABI(JS_FUNC_TO_DATA_PTR(void*, FinishBailoutToBaseline));
+            branchTest32(Zero, ReturnReg, ReturnReg, exceptionLabel());
+
+            // Restore values where they need to be and resume execution.
+            AllocatableGeneralRegisterSet enterMonRegs(GeneralRegisterSet::All());
+            enterMonRegs.take(R0);
+            enterMonRegs.take(ICStubReg);
+            enterMonRegs.take(BaselineFrameReg);
+            enterMonRegs.takeUnchecked(ICTailCallReg);
+
+            pop(ICStubReg);
+            pop(ICTailCallReg);
+            pop(BaselineFrameReg);
+            popValue(R0);
+
+            // Discard exit frame.
+            addToStackPtr(Imm32(ExitFrameLayout::SizeWithFooter()));
+
+#if defined(JS_CODEGEN_X86) || defined(JS_CODEGEN_X64)
+            push(ICTailCallReg);
+#endif
+            jump(Address(ICStubReg, ICStub::offsetOfStubCode()));
+        }
+
+        //
+        // Resuming into main jitcode.
+        //
+        bind(&noMonitor);
+        {
+            // Save needed values onto stack temporarily.
+            pushValue(Address(bailoutInfo, offsetof(BaselineBailoutInfo, valueR0)));
+            pushValue(Address(bailoutInfo, offsetof(BaselineBailoutInfo, valueR1)));
+            push(Address(bailoutInfo, offsetof(BaselineBailoutInfo, resumeFramePtr)));
+            push(Address(bailoutInfo, offsetof(BaselineBailoutInfo, resumeAddr)));
+
+            // Call a stub to free allocated memory and create arguments objects.
+            setupUnalignedABICall(temp);
+            passABIArg(bailoutInfo);
+            callWithABI(JS_FUNC_TO_DATA_PTR(void*, FinishBailoutToBaseline));
+            branchTest32(Zero, ReturnReg, ReturnReg, exceptionLabel());
+
+            // Restore values where they need to be and resume execution.
+            AllocatableGeneralRegisterSet enterRegs(GeneralRegisterSet::All());
+            enterRegs.take(R0);
+            enterRegs.take(R1);
+            enterRegs.take(BaselineFrameReg);
+            Register jitcodeReg = enterRegs.takeAny();
+
+            pop(jitcodeReg);
+            pop(BaselineFrameReg);
+            popValue(R1);
+            popValue(R0);
+
+            // Discard exit frame.
+            addToStackPtr(Imm32(ExitFrameLayout::SizeWithFooter()));
+
+            jump(jitcodeReg);
+        }
+    }
+}
+
+void
+MacroAssembler::loadBaselineOrIonRaw(Register script, Register dest, Label* failure)
+{
+    loadPtr(Address(script, JSScript::offsetOfBaselineOrIonRaw()), dest);
+    if (failure)
+        branchTestPtr(Assembler::Zero, dest, dest, failure);
+}
+
+void
+MacroAssembler::loadBaselineOrIonNoArgCheck(Register script, Register dest, Label* failure)
+{
+    loadPtr(Address(script, JSScript::offsetOfBaselineOrIonSkipArgCheck()), dest);
+    if (failure)
+        branchTestPtr(Assembler::Zero, dest, dest, failure);
+}
+
+void
+MacroAssembler::loadBaselineFramePtr(Register framePtr, Register dest)
+{
+    if (framePtr != dest)
+        movePtr(framePtr, dest);
+    subPtr(Imm32(BaselineFrame::Size()), dest);
+}
+
+void
+MacroAssembler::handleFailure()
+{
+    // Re-entry code is irrelevant because the exception will leave the
+    // running function and never come back
+    JitCode* excTail = GetJitContext()->runtime->jitRuntime()->getExceptionTail();
+    jump(excTail);
+}
+
+#ifdef DEBUG
+static void
+AssumeUnreachable_(const char* output) {
+    MOZ_ReportAssertionFailure(output, __FILE__, __LINE__);
+}
+#endif
+
+void
+MacroAssembler::assumeUnreachable(const char* output)
+{
+#ifdef DEBUG
+    if (!IsCompilingWasm()) {
+        AllocatableRegisterSet regs(RegisterSet::Volatile());
+        LiveRegisterSet save(regs.asLiveSet());
+        PushRegsInMask(save);
+        Register temp = regs.takeAnyGeneral();
+
+        setupUnalignedABICall(temp);
+        movePtr(ImmPtr(output), temp);
+        passABIArg(temp);
+        callWithABI(JS_FUNC_TO_DATA_PTR(void*, AssumeUnreachable_));
+
+        PopRegsInMask(save);
+    }
+#endif
+
+    breakpoint();
+}
+
+template<typename T>
+void
+MacroAssembler::assertTestInt32(Condition cond, const T& value, const char* output)
+{
+#ifdef DEBUG
+    Label ok;
+    branchTestInt32(cond, value, &ok);
+    assumeUnreachable(output);
+    bind(&ok);
+#endif
+}
+
+template void MacroAssembler::assertTestInt32(Condition, const Address&, const char*);
+
+static void
+Printf0_(const char* output) {
+    // Use stderr instead of stdout because this is only used for debug
+    // output. stderr is less likely to interfere with the program's normal
+    // output, and it's always unbuffered.
+    fprintf(stderr, "%s", output);
+}
+
+void
+MacroAssembler::printf(const char* output)
+{
+    AllocatableRegisterSet regs(RegisterSet::Volatile());
+    LiveRegisterSet save(regs.asLiveSet());
+    PushRegsInMask(save);
+
+    Register temp = regs.takeAnyGeneral();
+
+    setupUnalignedABICall(temp);
+    movePtr(ImmPtr(output), temp);
+    passABIArg(temp);
+    callWithABI(JS_FUNC_TO_DATA_PTR(void*, Printf0_));
+
+    PopRegsInMask(save);
+}
+
+static void
+Printf1_(const char* output, uintptr_t value) {
+    AutoEnterOOMUnsafeRegion oomUnsafe;
+    char* line = JS_sprintf_append(nullptr, output, value);
+    if (!line)
+        oomUnsafe.crash("OOM at masm.printf");
+    fprintf(stderr, "%s", line);
+    js_free(line);
+}
+
+void
+MacroAssembler::printf(const char* output, Register value)
+{
+    AllocatableRegisterSet regs(RegisterSet::Volatile());
+    LiveRegisterSet save(regs.asLiveSet());
+    PushRegsInMask(save);
+
+    regs.takeUnchecked(value);
+
+    Register temp = regs.takeAnyGeneral();
+
+    setupUnalignedABICall(temp);
+    movePtr(ImmPtr(output), temp);
+    passABIArg(temp);
+    passABIArg(value);
+    callWithABI(JS_FUNC_TO_DATA_PTR(void*, Printf1_));
+
+    PopRegsInMask(save);
+}
+
+#ifdef JS_TRACE_LOGGING
+void
+MacroAssembler::tracelogStartId(Register logger, uint32_t textId, bool force)
+{
+    if (!force && !TraceLogTextIdEnabled(textId))
+        return;
+
+    AllocatableRegisterSet regs(RegisterSet::Volatile());
+    LiveRegisterSet save(regs.asLiveSet());
+    PushRegsInMask(save);
+    regs.takeUnchecked(logger);
+
+    Register temp = regs.takeAnyGeneral();
+
+    setupUnalignedABICall(temp);
+    passABIArg(logger);
+    move32(Imm32(textId), temp);
+    passABIArg(temp);
+    callWithABI(JS_FUNC_TO_DATA_PTR(void*, TraceLogStartEventPrivate));
+
+    PopRegsInMask(save);
+}
+
+void
+MacroAssembler::tracelogStartId(Register logger, Register textId)
+{
+    AllocatableRegisterSet regs(RegisterSet::Volatile());
+    LiveRegisterSet save(regs.asLiveSet());
+    PushRegsInMask(save);
+    regs.takeUnchecked(logger);
+    regs.takeUnchecked(textId);
+
+    Register temp = regs.takeAnyGeneral();
+
+    setupUnalignedABICall(temp);
+    passABIArg(logger);
+    passABIArg(textId);
+    callWithABI(JS_FUNC_TO_DATA_PTR(void*, TraceLogStartEventPrivate));
+
+    PopRegsInMask(save);
+}
+
+void
+MacroAssembler::tracelogStartEvent(Register logger, Register event)
+{
+    void (&TraceLogFunc)(TraceLoggerThread*, const TraceLoggerEvent&) = TraceLogStartEvent;
+
+    AllocatableRegisterSet regs(RegisterSet::Volatile());
+    LiveRegisterSet save(regs.asLiveSet());
+    PushRegsInMask(save);
+    regs.takeUnchecked(logger);
+    regs.takeUnchecked(event);
+
+    Register temp = regs.takeAnyGeneral();
+
+    setupUnalignedABICall(temp);
+    passABIArg(logger);
+    passABIArg(event);
+    callWithABI(JS_FUNC_TO_DATA_PTR(void*, TraceLogFunc));
+
+    PopRegsInMask(save);
+}
+
+void
+MacroAssembler::tracelogStopId(Register logger, uint32_t textId, bool force)
+{
+    if (!force && !TraceLogTextIdEnabled(textId))
+        return;
+
+    AllocatableRegisterSet regs(RegisterSet::Volatile());
+    LiveRegisterSet save(regs.asLiveSet());
+    PushRegsInMask(save);
+    regs.takeUnchecked(logger);
+
+    Register temp = regs.takeAnyGeneral();
+
+    setupUnalignedABICall(temp);
+    passABIArg(logger);
+    move32(Imm32(textId), temp);
+    passABIArg(temp);
+
+    callWithABI(JS_FUNC_TO_DATA_PTR(void*, TraceLogStopEventPrivate));
+
+    PopRegsInMask(save);
+}
+
+void
+MacroAssembler::tracelogStopId(Register logger, Register textId)
+{
+    AllocatableRegisterSet regs(RegisterSet::Volatile());
+    LiveRegisterSet save(regs.asLiveSet());
+    PushRegsInMask(save);
+    regs.takeUnchecked(logger);
+    regs.takeUnchecked(textId);
+
+    Register temp = regs.takeAnyGeneral();
+
+    setupUnalignedABICall(temp);
+    passABIArg(logger);
+    passABIArg(textId);
+    callWithABI(JS_FUNC_TO_DATA_PTR(void*, TraceLogStopEventPrivate));
+
+    PopRegsInMask(save);
+}
+#endif
+
+void
+MacroAssembler::convertInt32ValueToDouble(const Address& address, Register scratch, Label* done)
+{
+    branchTestInt32(Assembler::NotEqual, address, done);
+    unboxInt32(address, scratch);
+    convertInt32ToDouble(scratch, ScratchDoubleReg);
+    storeDouble(ScratchDoubleReg, address);
+}
+
+void
+MacroAssembler::convertValueToFloatingPoint(ValueOperand value, FloatRegister output,
+                                            Label* fail, MIRType outputType)
+{
+    Register tag = splitTagForTest(value);
+
+    Label isDouble, isInt32, isBool, isNull, done;
+
+    branchTestDouble(Assembler::Equal, tag, &isDouble);
+    branchTestInt32(Assembler::Equal, tag, &isInt32);
+    branchTestBoolean(Assembler::Equal, tag, &isBool);
+    branchTestNull(Assembler::Equal, tag, &isNull);
+    branchTestUndefined(Assembler::NotEqual, tag, fail);
+
+    // fall-through: undefined
+    loadConstantFloatingPoint(GenericNaN(), float(GenericNaN()), output, outputType);
+    jump(&done);
+
+    bind(&isNull);
+    loadConstantFloatingPoint(0.0, 0.0f, output, outputType);
+    jump(&done);
+
+    bind(&isBool);
+    boolValueToFloatingPoint(value, output, outputType);
+    jump(&done);
+
+    bind(&isInt32);
+    int32ValueToFloatingPoint(value, output, outputType);
+    jump(&done);
+
+    bind(&isDouble);
+    FloatRegister tmp = output;
+    if (outputType == MIRType::Float32 && hasMultiAlias())
+        tmp = ScratchDoubleReg;
+
+    unboxDouble(value, tmp);
+    if (outputType == MIRType::Float32)
+        convertDoubleToFloat32(tmp, output);
+
+    bind(&done);
+}
+
+bool
+MacroAssembler::convertValueToFloatingPoint(JSContext* cx, const Value& v, FloatRegister output,
+                                            Label* fail, MIRType outputType)
+{
+    if (v.isNumber() || v.isString()) {
+        double d;
+        if (v.isNumber())
+            d = v.toNumber();
+        else if (!StringToNumber(cx, v.toString(), &d))
+            return false;
+
+        loadConstantFloatingPoint(d, (float)d, output, outputType);
+        return true;
+    }
+
+    if (v.isBoolean()) {
+        if (v.toBoolean())
+            loadConstantFloatingPoint(1.0, 1.0f, output, outputType);
+        else
+            loadConstantFloatingPoint(0.0, 0.0f, output, outputType);
+        return true;
+    }
+
+    if (v.isNull()) {
+        loadConstantFloatingPoint(0.0, 0.0f, output, outputType);
+        return true;
+    }
+
+    if (v.isUndefined()) {
+        loadConstantFloatingPoint(GenericNaN(), float(GenericNaN()), output, outputType);
+        return true;
+    }
+
+    MOZ_ASSERT(v.isObject() || v.isSymbol());
+    jump(fail);
+    return true;
+}
+
+bool
+MacroAssembler::convertConstantOrRegisterToFloatingPoint(JSContext* cx,
+                                                         const ConstantOrRegister& src,
+                                                         FloatRegister output, Label* fail,
+                                                         MIRType outputType)
+{
+    if (src.constant())
+        return convertValueToFloatingPoint(cx, src.value(), output, fail, outputType);
+
+    convertTypedOrValueToFloatingPoint(src.reg(), output, fail, outputType);
+    return true;
+}
+
+void
+MacroAssembler::convertTypedOrValueToFloatingPoint(TypedOrValueRegister src, FloatRegister output,
+                                                   Label* fail, MIRType outputType)
+{
+    MOZ_ASSERT(IsFloatingPointType(outputType));
+
+    if (src.hasValue()) {
+        convertValueToFloatingPoint(src.valueReg(), output, fail, outputType);
+        return;
+    }
+
+    bool outputIsDouble = outputType == MIRType::Double;
+    switch (src.type()) {
+      case MIRType::Null:
+        loadConstantFloatingPoint(0.0, 0.0f, output, outputType);
+        break;
+      case MIRType::Boolean:
+      case MIRType::Int32:
+        convertInt32ToFloatingPoint(src.typedReg().gpr(), output, outputType);
+        break;
+      case MIRType::Float32:
+        if (outputIsDouble) {
+            convertFloat32ToDouble(src.typedReg().fpu(), output);
+        } else {
+            if (src.typedReg().fpu() != output)
+                moveFloat32(src.typedReg().fpu(), output);
+        }
+        break;
+      case MIRType::Double:
+        if (outputIsDouble) {
+            if (src.typedReg().fpu() != output)
+                moveDouble(src.typedReg().fpu(), output);
+        } else {
+            convertDoubleToFloat32(src.typedReg().fpu(), output);
+        }
+        break;
+      case MIRType::Object:
+      case MIRType::String:
+      case MIRType::Symbol:
+        jump(fail);
+        break;
+      case MIRType::Undefined:
+        loadConstantFloatingPoint(GenericNaN(), float(GenericNaN()), output, outputType);
+        break;
+      default:
+        MOZ_CRASH("Bad MIRType");
+    }
+}
+
+void
+MacroAssembler::outOfLineTruncateSlow(FloatRegister src, Register dest, bool widenFloatToDouble,
+                                      bool compilingWasm)
+{
+#if defined(JS_CODEGEN_ARM) || defined(JS_CODEGEN_ARM64) || \
+    defined(JS_CODEGEN_MIPS32) || defined(JS_CODEGEN_MIPS64)
+    if (widenFloatToDouble) {
+        convertFloat32ToDouble(src, ScratchDoubleReg);
+        src = ScratchDoubleReg;
+    }
+#elif defined(JS_CODEGEN_X86) || defined(JS_CODEGEN_X64)
+    FloatRegister srcSingle;
+    if (widenFloatToDouble) {
+        MOZ_ASSERT(src.isSingle());
+        srcSingle = src;
+        src = src.asDouble();
+        push(srcSingle);
+        convertFloat32ToDouble(srcSingle, src);
+    }
+#else
+    // Also see below
+    MOZ_CRASH("MacroAssembler platform hook: outOfLineTruncateSlow");
+#endif
+
+    MOZ_ASSERT(src.isDouble());
+
+    setupUnalignedABICall(dest);
+    passABIArg(src, MoveOp::DOUBLE);
+    if (compilingWasm)
+        callWithABI(wasm::SymbolicAddress::ToInt32);
+    else
+        callWithABI(mozilla::BitwiseCast<void*, int32_t(*)(double)>(JS::ToInt32));
+    storeCallInt32Result(dest);
+
+#if defined(JS_CODEGEN_ARM) || defined(JS_CODEGEN_ARM64) || \
+    defined(JS_CODEGEN_MIPS32) || defined(JS_CODEGEN_MIPS64)
+    // Nothing
+#elif defined(JS_CODEGEN_X86) || defined(JS_CODEGEN_X64)
+    if (widenFloatToDouble)
+        pop(srcSingle);
+#else
+    MOZ_CRASH("MacroAssembler platform hook: outOfLineTruncateSlow");
+#endif
+}
+
+void
+MacroAssembler::convertDoubleToInt(FloatRegister src, Register output, FloatRegister temp,
+                                   Label* truncateFail, Label* fail,
+                                   IntConversionBehavior behavior)
+{
+    switch (behavior) {
+      case IntConversion_Normal:
+      case IntConversion_NegativeZeroCheck:
+        convertDoubleToInt32(src, output, fail, behavior == IntConversion_NegativeZeroCheck);
+        break;
+      case IntConversion_Truncate:
+        branchTruncateDoubleMaybeModUint32(src, output, truncateFail ? truncateFail : fail);
+        break;
+      case IntConversion_ClampToUint8:
+        // Clamping clobbers the input register, so use a temp.
+        moveDouble(src, temp);
+        clampDoubleToUint8(temp, output);
+        break;
+    }
+}
+
+void
+MacroAssembler::convertValueToInt(ValueOperand value, MDefinition* maybeInput,
+                                  Label* handleStringEntry, Label* handleStringRejoin,
+                                  Label* truncateDoubleSlow,
+                                  Register stringReg, FloatRegister temp, Register output,
+                                  Label* fail, IntConversionBehavior behavior,
+                                  IntConversionInputKind conversion)
+{
+    Register tag = splitTagForTest(value);
+    bool handleStrings = (behavior == IntConversion_Truncate ||
+                          behavior == IntConversion_ClampToUint8) &&
+                         handleStringEntry &&
+                         handleStringRejoin;
+
+    MOZ_ASSERT_IF(handleStrings, conversion == IntConversion_Any);
+
+    Label done, isInt32, isBool, isDouble, isNull, isString;
+
+    maybeBranchTestType(MIRType::Int32, maybeInput, tag, &isInt32);
+    if (conversion == IntConversion_Any || conversion == IntConversion_NumbersOrBoolsOnly)
+        maybeBranchTestType(MIRType::Boolean, maybeInput, tag, &isBool);
+    maybeBranchTestType(MIRType::Double, maybeInput, tag, &isDouble);
+
+    if (conversion == IntConversion_Any) {
+        // If we are not truncating, we fail for anything that's not
+        // null. Otherwise we might be able to handle strings and objects.
+        switch (behavior) {
+          case IntConversion_Normal:
+          case IntConversion_NegativeZeroCheck:
+            branchTestNull(Assembler::NotEqual, tag, fail);
+            break;
+
+          case IntConversion_Truncate:
+          case IntConversion_ClampToUint8:
+            maybeBranchTestType(MIRType::Null, maybeInput, tag, &isNull);
+            if (handleStrings)
+                maybeBranchTestType(MIRType::String, maybeInput, tag, &isString);
+            maybeBranchTestType(MIRType::Object, maybeInput, tag, fail);
+            branchTestUndefined(Assembler::NotEqual, tag, fail);
+            break;
+        }
+    } else {
+        jump(fail);
+    }
+
+    // The value is null or undefined in truncation contexts - just emit 0.
+    if (isNull.used())
+        bind(&isNull);
+    mov(ImmWord(0), output);
+    jump(&done);
+
+    // Try converting a string into a double, then jump to the double case.
+    if (handleStrings) {
+        bind(&isString);
+        unboxString(value, stringReg);
+        jump(handleStringEntry);
+    }
+
+    // Try converting double into integer.
+    if (isDouble.used() || handleStrings) {
+        if (isDouble.used()) {
+            bind(&isDouble);
+            unboxDouble(value, temp);
+        }
+
+        if (handleStrings)
+            bind(handleStringRejoin);
+
+        convertDoubleToInt(temp, output, temp, truncateDoubleSlow, fail, behavior);
+        jump(&done);
+    }
+
+    // Just unbox a bool, the result is 0 or 1.
+    if (isBool.used()) {
+        bind(&isBool);
+        unboxBoolean(value, output);
+        jump(&done);
+    }
+
+    // Integers can be unboxed.
+    if (isInt32.used()) {
+        bind(&isInt32);
+        unboxInt32(value, output);
+        if (behavior == IntConversion_ClampToUint8)
+            clampIntToUint8(output);
+    }
+
+    bind(&done);
+}
+
+bool
+MacroAssembler::convertValueToInt(JSContext* cx, const Value& v, Register output, Label* fail,
+                                  IntConversionBehavior behavior)
+{
+    bool handleStrings = (behavior == IntConversion_Truncate ||
+                          behavior == IntConversion_ClampToUint8);
+
+    if (v.isNumber() || (handleStrings && v.isString())) {
+        double d;
+        if (v.isNumber())
+            d = v.toNumber();
+        else if (!StringToNumber(cx, v.toString(), &d))
+            return false;
+
+        switch (behavior) {
+          case IntConversion_Normal:
+          case IntConversion_NegativeZeroCheck: {
+            // -0 is checked anyways if we have a constant value.
+            int i;
+            if (mozilla::NumberIsInt32(d, &i))
+                move32(Imm32(i), output);
+            else
+                jump(fail);
+            break;
+          }
+          case IntConversion_Truncate:
+            move32(Imm32(ToInt32(d)), output);
+            break;
+          case IntConversion_ClampToUint8:
+            move32(Imm32(ClampDoubleToUint8(d)), output);
+            break;
+        }
+
+        return true;
+    }
+
+    if (v.isBoolean()) {
+        move32(Imm32(v.toBoolean() ? 1 : 0), output);
+        return true;
+    }
+
+    if (v.isNull() || v.isUndefined()) {
+        move32(Imm32(0), output);
+        return true;
+    }
+
+    MOZ_ASSERT(v.isObject() || v.isSymbol());
+
+    jump(fail);
+    return true;
+}
+
+bool
+MacroAssembler::convertConstantOrRegisterToInt(JSContext* cx,
+                                               const ConstantOrRegister& src,
+                                               FloatRegister temp, Register output,
+                                               Label* fail, IntConversionBehavior behavior)
+{
+    if (src.constant())
+        return convertValueToInt(cx, src.value(), output, fail, behavior);
+
+    convertTypedOrValueToInt(src.reg(), temp, output, fail, behavior);
+    return true;
+}
+
+void
+MacroAssembler::convertTypedOrValueToInt(TypedOrValueRegister src, FloatRegister temp,
+                                         Register output, Label* fail,
+                                         IntConversionBehavior behavior)
+{
+    if (src.hasValue()) {
+        convertValueToInt(src.valueReg(), temp, output, fail, behavior);
+        return;
+    }
+
+    switch (src.type()) {
+      case MIRType::Undefined:
+      case MIRType::Null:
+        move32(Imm32(0), output);
+        break;
+      case MIRType::Boolean:
+      case MIRType::Int32:
+        if (src.typedReg().gpr() != output)
+            move32(src.typedReg().gpr(), output);
+        if (src.type() == MIRType::Int32 && behavior == IntConversion_ClampToUint8)
+            clampIntToUint8(output);
+        break;
+      case MIRType::Double:
+        convertDoubleToInt(src.typedReg().fpu(), output, temp, nullptr, fail, behavior);
+        break;
+      case MIRType::Float32:
+        // Conversion to Double simplifies implementation at the expense of performance.
+        convertFloat32ToDouble(src.typedReg().fpu(), temp);
+        convertDoubleToInt(temp, output, temp, nullptr, fail, behavior);
+        break;
+      case MIRType::String:
+      case MIRType::Symbol:
+      case MIRType::Object:
+        jump(fail);
+        break;
+      default:
+        MOZ_CRASH("Bad MIRType");
+    }
+}
+
+void
+MacroAssembler::finish()
+{
+    if (failureLabel_.used()) {
+        bind(&failureLabel_);
+        handleFailure();
+    }
+
+    MacroAssemblerSpecific::finish();
+}
+
+void
+MacroAssembler::link(JitCode* code)
+{
+    MOZ_ASSERT(!oom());
+    linkSelfReference(code);
+    linkProfilerCallSites(code);
+}
+
+MacroAssembler::AutoProfilerCallInstrumentation::AutoProfilerCallInstrumentation(
+    MacroAssembler& masm
+    MOZ_GUARD_OBJECT_NOTIFIER_PARAM_IN_IMPL)
+{
+    MOZ_GUARD_OBJECT_NOTIFIER_INIT;
+    if (!masm.emitProfilingInstrumentation_)
+        return;
+
+    Register reg = CallTempReg0;
+    Register reg2 = CallTempReg1;
+    masm.push(reg);
+    masm.push(reg2);
+
+    JitContext* icx = GetJitContext();
+    AbsoluteAddress profilingActivation(icx->runtime->addressOfProfilingActivation());
+
+    CodeOffset label = masm.movWithPatch(ImmWord(uintptr_t(-1)), reg);
+    masm.loadPtr(profilingActivation, reg2);
+    masm.storePtr(reg, Address(reg2, JitActivation::offsetOfLastProfilingCallSite()));
+
+    masm.appendProfilerCallSite(label);
+
+    masm.pop(reg2);
+    masm.pop(reg);
+}
+
+void
+MacroAssembler::linkProfilerCallSites(JitCode* code)
+{
+    for (size_t i = 0; i < profilerCallSites_.length(); i++) {
+        CodeOffset offset = profilerCallSites_[i];
+        CodeLocationLabel location(code, offset);
+        PatchDataWithValueCheck(location, ImmPtr(location.raw()), ImmPtr((void*)-1));
+    }
+}
+
+void
+MacroAssembler::alignJitStackBasedOnNArgs(Register nargs)
+{
+    if (JitStackValueAlignment == 1)
+        return;
+
+    // A JitFrameLayout is composed of the following:
+    // [padding?] [argN] .. [arg1] [this] [[argc] [callee] [descr] [raddr]]
+    //
+    // We want to ensure that the |raddr| address is aligned.
+    // Which implies that we want to ensure that |this| is aligned.
+    static_assert(sizeof(JitFrameLayout) % JitStackAlignment == 0,
+      "No need to consider the JitFrameLayout for aligning the stack");
+
+    // Which implies that |argN| is aligned if |nargs| is even, and offset by
+    // |sizeof(Value)| if |nargs| is odd.
+    MOZ_ASSERT(JitStackValueAlignment == 2);
+
+    // Thus the |padding| is offset by |sizeof(Value)| if |nargs| is even, and
+    // aligned if |nargs| is odd.
+
+    // if (nargs % 2 == 0) {
+    //     if (sp % JitStackAlignment == 0)
+    //         sp -= sizeof(Value);
+    //     MOZ_ASSERT(sp % JitStackAlignment == JitStackAlignment - sizeof(Value));
+    // } else {
+    //     sp = sp & ~(JitStackAlignment - 1);
+    // }
+    Label odd, end;
+    Label* maybeAssert = &end;
+#ifdef DEBUG
+    Label assert;
+    maybeAssert = &assert;
+#endif
+    assertStackAlignment(sizeof(Value), 0);
+    branchTestPtr(Assembler::NonZero, nargs, Imm32(1), &odd);
+    branchTestStackPtr(Assembler::NonZero, Imm32(JitStackAlignment - 1), maybeAssert);
+    subFromStackPtr(Imm32(sizeof(Value)));
+#ifdef DEBUG
+    bind(&assert);
+#endif
+    assertStackAlignment(JitStackAlignment, sizeof(Value));
+    jump(&end);
+    bind(&odd);
+    andToStackPtr(Imm32(~(JitStackAlignment - 1)));
+    bind(&end);
+}
+
+void
+MacroAssembler::alignJitStackBasedOnNArgs(uint32_t nargs)
+{
+    if (JitStackValueAlignment == 1)
+        return;
+
+    // A JitFrameLayout is composed of the following:
+    // [padding?] [argN] .. [arg1] [this] [[argc] [callee] [descr] [raddr]]
+    //
+    // We want to ensure that the |raddr| address is aligned.
+    // Which implies that we want to ensure that |this| is aligned.
+    static_assert(sizeof(JitFrameLayout) % JitStackAlignment == 0,
+      "No need to consider the JitFrameLayout for aligning the stack");
+
+    // Which implies that |argN| is aligned if |nargs| is even, and offset by
+    // |sizeof(Value)| if |nargs| is odd.
+    MOZ_ASSERT(JitStackValueAlignment == 2);
+
+    // Thus the |padding| is offset by |sizeof(Value)| if |nargs| is even, and
+    // aligned if |nargs| is odd.
+
+    assertStackAlignment(sizeof(Value), 0);
+    if (nargs % 2 == 0) {
+        Label end;
+        branchTestStackPtr(Assembler::NonZero, Imm32(JitStackAlignment - 1), &end);
+        subFromStackPtr(Imm32(sizeof(Value)));
+        bind(&end);
+        assertStackAlignment(JitStackAlignment, sizeof(Value));
+    } else {
+        andToStackPtr(Imm32(~(JitStackAlignment - 1)));
+    }
+}
+
+// ===============================================================
+
+MacroAssembler::MacroAssembler(JSContext* cx, IonScript* ion,
+                               JSScript* script, jsbytecode* pc)
+  : framePushed_(0),
+#ifdef DEBUG
+    inCall_(false),
+#endif
+    emitProfilingInstrumentation_(false)
+{
+    constructRoot(cx);
+    jitContext_.emplace(cx, (js::jit::TempAllocator*)nullptr);
+    alloc_.emplace(cx);
+    moveResolver_.setAllocator(*jitContext_->temp);
+#if defined(JS_CODEGEN_ARM)
+    initWithAllocator();
+    m_buffer.id = GetJitContext()->getNextAssemblerId();
+#elif defined(JS_CODEGEN_ARM64)
+    initWithAllocator();
+    armbuffer_.id = GetJitContext()->getNextAssemblerId();
+#endif
+    if (ion) {
+        setFramePushed(ion->frameSize());
+        if (pc && cx->runtime()->spsProfiler.enabled())
+            enableProfilingInstrumentation();
+    }
+}
+
+MacroAssembler::AfterICSaveLive
+MacroAssembler::icSaveLive(LiveRegisterSet& liveRegs)
+{
+    PushRegsInMask(liveRegs);
+    AfterICSaveLive aic(framePushed());
+    alignFrameForICArguments(aic);
+    return aic;
+}
+
+bool
+MacroAssembler::icBuildOOLFakeExitFrame(void* fakeReturnAddr, AfterICSaveLive& aic)
+{
+    return buildOOLFakeExitFrame(fakeReturnAddr);
+}
+
+void
+MacroAssembler::icRestoreLive(LiveRegisterSet& liveRegs, AfterICSaveLive& aic)
+{
+    restoreFrameAlignmentForICArguments(aic);
+    MOZ_ASSERT(framePushed() == aic.initialStack);
+    PopRegsInMask(liveRegs);
+}
+
+#ifndef JS_CODEGEN_ARM64
+void
+MacroAssembler::subFromStackPtr(Register reg)
+{
+    subPtr(reg, getStackPointer());
+}
+#endif // JS_CODEGEN_ARM64
+
+//{{{ check_macroassembler_style
+// ===============================================================
+// Stack manipulation functions.
+
+void
+MacroAssembler::PushRegsInMask(LiveGeneralRegisterSet set)
+{
+    PushRegsInMask(LiveRegisterSet(set.set(), FloatRegisterSet()));
+}
+
+void
+MacroAssembler::PopRegsInMask(LiveRegisterSet set)
+{
+    PopRegsInMaskIgnore(set, LiveRegisterSet());
+}
+
+void
+MacroAssembler::PopRegsInMask(LiveGeneralRegisterSet set)
+{
+    PopRegsInMask(LiveRegisterSet(set.set(), FloatRegisterSet()));
+}
+
+void
+MacroAssembler::Push(jsid id, Register scratchReg)
+{
+    if (JSID_IS_GCTHING(id)) {
+        // If we're pushing a gcthing, then we can't just push the tagged jsid
+        // value since the GC won't have any idea that the push instruction
+        // carries a reference to a gcthing.  Need to unpack the pointer,
+        // push it using ImmGCPtr, and then rematerialize the id at runtime.
+
+        if (JSID_IS_STRING(id)) {
+            JSString* str = JSID_TO_STRING(id);
+            MOZ_ASSERT(((size_t)str & JSID_TYPE_MASK) == 0);
+            MOZ_ASSERT(JSID_TYPE_STRING == 0x0);
+            Push(ImmGCPtr(str));
+        } else {
+            MOZ_ASSERT(JSID_IS_SYMBOL(id));
+            JS::Symbol* sym = JSID_TO_SYMBOL(id);
+            movePtr(ImmGCPtr(sym), scratchReg);
+            orPtr(Imm32(JSID_TYPE_SYMBOL), scratchReg);
+            Push(scratchReg);
+        }
+    } else {
+        Push(ImmWord(JSID_BITS(id)));
+    }
+}
+
+void
+MacroAssembler::Push(TypedOrValueRegister v)
+{
+    if (v.hasValue()) {
+        Push(v.valueReg());
+    } else if (IsFloatingPointType(v.type())) {
+        FloatRegister reg = v.typedReg().fpu();
+        if (v.type() == MIRType::Float32) {
+            convertFloat32ToDouble(reg, ScratchDoubleReg);
+            reg = ScratchDoubleReg;
+        }
+        Push(reg);
+    } else {
+        Push(ValueTypeFromMIRType(v.type()), v.typedReg().gpr());
+    }
+}
+
+void
+MacroAssembler::Push(const ConstantOrRegister& v)
+{
+    if (v.constant())
+        Push(v.value());
+    else
+        Push(v.reg());
+}
+
+void
+MacroAssembler::Push(const ValueOperand& val)
+{
+    pushValue(val);
+    framePushed_ += sizeof(Value);
+}
+
+void
+MacroAssembler::Push(const Value& val)
+{
+    pushValue(val);
+    framePushed_ += sizeof(Value);
+}
+
+void
+MacroAssembler::Push(JSValueType type, Register reg)
+{
+    pushValue(type, reg);
+    framePushed_ += sizeof(Value);
+}
+
+void
+MacroAssembler::PushValue(const Address& addr)
+{
+    MOZ_ASSERT(addr.base != getStackPointer());
+    pushValue(addr);
+    framePushed_ += sizeof(Value);
+}
+
+void
+MacroAssembler::PushEmptyRooted(VMFunction::RootType rootType)
+{
+    switch (rootType) {
+      case VMFunction::RootNone:
+        MOZ_CRASH("Handle must have root type");
+      case VMFunction::RootObject:
+      case VMFunction::RootString:
+      case VMFunction::RootPropertyName:
+      case VMFunction::RootFunction:
+      case VMFunction::RootCell:
+        Push(ImmPtr(nullptr));
+        break;
+      case VMFunction::RootValue:
+        Push(UndefinedValue());
+        break;
+    }
+}
+
+void
+MacroAssembler::popRooted(VMFunction::RootType rootType, Register cellReg,
+                          const ValueOperand& valueReg)
+{
+    switch (rootType) {
+      case VMFunction::RootNone:
+        MOZ_CRASH("Handle must have root type");
+      case VMFunction::RootObject:
+      case VMFunction::RootString:
+      case VMFunction::RootPropertyName:
+      case VMFunction::RootFunction:
+      case VMFunction::RootCell:
+        Pop(cellReg);
+        break;
+      case VMFunction::RootValue:
+        Pop(valueReg);
+        break;
+    }
+}
+
+void
+MacroAssembler::adjustStack(int amount)
+{
+    if (amount > 0)
+        freeStack(amount);
+    else if (amount < 0)
+        reserveStack(-amount);
+}
+
+void
+MacroAssembler::freeStack(uint32_t amount)
+{
+    MOZ_ASSERT(amount <= framePushed_);
+    if (amount)
+        addToStackPtr(Imm32(amount));
+    framePushed_ -= amount;
+}
+
+void
+MacroAssembler::freeStack(Register amount)
+{
+    addToStackPtr(amount);
+}
+
+// ===============================================================
+// ABI function calls.
+
+void
+MacroAssembler::setupABICall()
+{
+#ifdef DEBUG
+    MOZ_ASSERT(!inCall_);
+    inCall_ = true;
+#endif
+
+#ifdef JS_SIMULATOR
+    signature_ = 0;
+#endif
+
+    // Reinitialize the ABIArg generator.
+    abiArgs_ = ABIArgGenerator();
+
+#if defined(JS_CODEGEN_ARM)
+    // On ARM, we need to know what ABI we are using, either in the
+    // simulator, or based on the configure flags.
+#if defined(JS_SIMULATOR_ARM)
+    abiArgs_.setUseHardFp(UseHardFpABI());
+#elif defined(JS_CODEGEN_ARM_HARDFP)
+    abiArgs_.setUseHardFp(true);
+#else
+    abiArgs_.setUseHardFp(false);
+#endif
+#endif
+
+#if defined(JS_CODEGEN_MIPS32)
+    // On MIPS, the system ABI use general registers pairs to encode double
+    // arguments, after one or 2 integer-like arguments. Unfortunately, the
+    // Lowering phase is not capable to express it at the moment. So we enforce
+    // the system ABI here.
+    abiArgs_.enforceO32ABI();
+#endif
+}
+
+void
+MacroAssembler::setupAlignedABICall()
+{
+    setupABICall();
+    dynamicAlignment_ = false;
+    assertStackAlignment(ABIStackAlignment);
+
+#if defined(JS_CODEGEN_ARM64)
+    MOZ_CRASH("Not supported on arm64");
+#endif
+}
+
+void
+MacroAssembler::passABIArg(const MoveOperand& from, MoveOp::Type type)
+{
+    MOZ_ASSERT(inCall_);
+    appendSignatureType(type);
+
+    ABIArg arg;
+    switch (type) {
+      case MoveOp::FLOAT32:
+        arg = abiArgs_.next(MIRType::Float32);
+        break;
+      case MoveOp::DOUBLE:
+        arg = abiArgs_.next(MIRType::Double);
+        break;
+      case MoveOp::GENERAL:
+        arg = abiArgs_.next(MIRType::Pointer);
+        break;
+      default:
+        MOZ_CRASH("Unexpected argument type");
+    }
+
+    MoveOperand to(*this, arg);
+    if (from == to)
+        return;
+
+    if (oom())
+        return;
+    propagateOOM(moveResolver_.addMove(from, to, type));
+}
+
+void
+MacroAssembler::callWithABINoProfiler(void* fun, MoveOp::Type result)
+{
+    appendSignatureType(result);
+#ifdef JS_SIMULATOR
+    fun = Simulator::RedirectNativeFunction(fun, signature());
+#endif
+
+    uint32_t stackAdjust;
+    callWithABIPre(&stackAdjust);
+    call(ImmPtr(fun));
+    callWithABIPost(stackAdjust, result);
+}
+
+void
+MacroAssembler::callWithABINoProfiler(wasm::SymbolicAddress imm, MoveOp::Type result)
+{
+    uint32_t stackAdjust;
+    callWithABIPre(&stackAdjust, /* callFromWasm = */ true);
+    call(imm);
+    callWithABIPost(stackAdjust, result);
+}
+
+// ===============================================================
+// Exit frame footer.
+
+void
+MacroAssembler::linkExitFrame()
+{
+    AbsoluteAddress jitTop(GetJitContext()->runtime->addressOfJitTop());
+    storeStackPtr(jitTop);
+}
+
+void
+MacroAssembler::linkSelfReference(JitCode* code)
+{
+    // If this code can transition to C++ code and witness a GC, then we need to store
+    // the JitCode onto the stack in order to GC it correctly.  exitCodePatch should
+    // be unset if the code never needed to push its JitCode*.
+    if (hasSelfReference()) {
+        PatchDataWithValueCheck(CodeLocationLabel(code, selfReferencePatch_),
+                                ImmPtr(code),
+                                ImmPtr((void*)-1));
+    }
+}
+
+// ===============================================================
+// Branch functions
+
+void
+MacroAssembler::branchIfNotInterpretedConstructor(Register fun, Register scratch, Label* label)
+{
+    // 16-bit loads are slow and unaligned 32-bit loads may be too so
+    // perform an aligned 32-bit load and adjust the bitmask accordingly.
+    MOZ_ASSERT(JSFunction::offsetOfNargs() % sizeof(uint32_t) == 0);
+    MOZ_ASSERT(JSFunction::offsetOfFlags() == JSFunction::offsetOfNargs() + 2);
+
+    // First, ensure it's a scripted function.
+    load32(Address(fun, JSFunction::offsetOfNargs()), scratch);
+    int32_t bits = IMM32_16ADJ(JSFunction::INTERPRETED);
+    branchTest32(Assembler::Zero, scratch, Imm32(bits), label);
+
+    // Check if the CONSTRUCTOR bit is set.
+    bits = IMM32_16ADJ(JSFunction::CONSTRUCTOR);
+    branchTest32(Assembler::Zero, scratch, Imm32(bits), label);
+}
+
+void
+MacroAssembler::maybeBranchTestType(MIRType type, MDefinition* maybeDef, Register tag, Label* label)
+{
+    if (!maybeDef || maybeDef->mightBeType(type)) {
+        switch (type) {
+          case MIRType::Null:
+            branchTestNull(Equal, tag, label);
+            break;
+          case MIRType::Boolean:
+            branchTestBoolean(Equal, tag, label);
+            break;
+          case MIRType::Int32:
+            branchTestInt32(Equal, tag, label);
+            break;
+          case MIRType::Double:
+            branchTestDouble(Equal, tag, label);
+            break;
+          case MIRType::String:
+            branchTestString(Equal, tag, label);
+            break;
+          case MIRType::Symbol:
+            branchTestSymbol(Equal, tag, label);
+            break;
+          case MIRType::Object:
+            branchTestObject(Equal, tag, label);
+            break;
+          default:
+            MOZ_CRASH("Unsupported type");
+        }
+    }
+}
+
+void
+MacroAssembler::wasmCallImport(const wasm::CallSiteDesc& desc, const wasm::CalleeDesc& callee)
+{
+    // Load the callee, before the caller's registers are clobbered.
+    uint32_t globalDataOffset = callee.importGlobalDataOffset();
+    loadWasmGlobalPtr(globalDataOffset + offsetof(wasm::FuncImportTls, code), ABINonArgReg0);
+
+    MOZ_ASSERT(ABINonArgReg0 != WasmTlsReg, "by constraint");
+
+    // Switch to the callee's TLS and pinned registers and make the call.
+    loadWasmGlobalPtr(globalDataOffset + offsetof(wasm::FuncImportTls, tls), WasmTlsReg);
+    loadWasmPinnedRegsFromTls();
+
+    call(desc, ABINonArgReg0);
+}
+
+void
+MacroAssembler::wasmCallBuiltinInstanceMethod(const ABIArg& instanceArg,
+                                              wasm::SymbolicAddress builtin)
+{
+    MOZ_ASSERT(instanceArg != ABIArg());
+
+    if (instanceArg.kind() == ABIArg::GPR) {
+        loadPtr(Address(WasmTlsReg, offsetof(wasm::TlsData, instance)), instanceArg.gpr());
+    } else if (instanceArg.kind() == ABIArg::Stack) {
+        // Safe to use ABINonArgReg0 since its the last thing before the call
+        Register scratch = ABINonArgReg0;
+        loadPtr(Address(WasmTlsReg, offsetof(wasm::TlsData, instance)), scratch);
+        storePtr(scratch, Address(getStackPointer(), instanceArg.offsetFromArgBase()));
+    } else {
+        MOZ_CRASH("Unknown abi passing style for pointer");
+    }
+
+    call(builtin);
+}
+
+void
+MacroAssembler::wasmCallIndirect(const wasm::CallSiteDesc& desc, const wasm::CalleeDesc& callee)
+{
+    Register scratch = WasmTableCallScratchReg;
+    Register index = WasmTableCallIndexReg;
+
+    if (callee.which() == wasm::CalleeDesc::AsmJSTable) {
+        // asm.js tables require no signature check, have had their index masked
+        // into range and thus need no bounds check and cannot be external.
+        loadWasmGlobalPtr(callee.tableBaseGlobalDataOffset(), scratch);
+        loadPtr(BaseIndex(scratch, index, ScalePointer), scratch);
+        call(desc, scratch);
+        return;
+    }
+
+    MOZ_ASSERT(callee.which() == wasm::CalleeDesc::WasmTable);
+
+    // Write the sig-id into the ABI sig-id register.
+    wasm::SigIdDesc sigId = callee.wasmTableSigId();
+    switch (sigId.kind()) {
+      case wasm::SigIdDesc::Kind::Global:
+        loadWasmGlobalPtr(sigId.globalDataOffset(), WasmTableCallSigReg);
+        break;
+      case wasm::SigIdDesc::Kind::Immediate:
+        move32(Imm32(sigId.immediate()), WasmTableCallSigReg);
+        break;
+      case wasm::SigIdDesc::Kind::None:
+        break;
+    }
+
+    // WebAssembly throws if the index is out-of-bounds.
+    loadWasmGlobalPtr(callee.tableLengthGlobalDataOffset(), scratch);
+
+    wasm::TrapOffset trapOffset(desc.lineOrBytecode());
+    wasm::TrapDesc oobTrap(trapOffset, wasm::Trap::OutOfBounds, framePushed());
+    branch32(Assembler::Condition::AboveOrEqual, index, scratch, oobTrap);
+
+    // Load the base pointer of the table.
+    loadWasmGlobalPtr(callee.tableBaseGlobalDataOffset(), scratch);
+
+    // Load the callee from the table.
+    wasm::TrapDesc nullTrap(trapOffset, wasm::Trap::IndirectCallToNull, framePushed());
+    if (callee.wasmTableIsExternal()) {
+        static_assert(sizeof(wasm::ExternalTableElem) == 8 || sizeof(wasm::ExternalTableElem) == 16,
+                      "elements of external tables are two words");
+        if (sizeof(wasm::ExternalTableElem) == 8) {
+            computeEffectiveAddress(BaseIndex(scratch, index, TimesEight), scratch);
+        } else {
+            lshift32(Imm32(4), index);
+            addPtr(index, scratch);
+        }
+
+        loadPtr(Address(scratch, offsetof(wasm::ExternalTableElem, tls)), WasmTlsReg);
+        branchTest32(Assembler::Zero, WasmTlsReg, WasmTlsReg, nullTrap);
+
+        loadWasmPinnedRegsFromTls();
+
+        loadPtr(Address(scratch, offsetof(wasm::ExternalTableElem, code)), scratch);
+    } else {
+        loadPtr(BaseIndex(scratch, index, ScalePointer), scratch);
+        branchTest32(Assembler::Zero, scratch, scratch, nullTrap);
+    }
+
+    call(desc, scratch);
+}
+
+void
+MacroAssembler::wasmEmitTrapOutOfLineCode()
+{
+    for (const wasm::TrapSite& site : trapSites()) {
+        // Trap out-of-line codes are created for two kinds of trap sites:
+        //  - jumps, which are bound directly to the trap out-of-line path
+        //  - memory accesses, which can fault and then have control transferred
+        //    to the out-of-line path directly via signal handler setting pc
+        switch (site.kind) {
+          case wasm::TrapSite::Jump: {
+            RepatchLabel jump;
+            jump.use(site.codeOffset);
+            bind(&jump);
+            break;
+          }
+          case wasm::TrapSite::MemoryAccess: {
+            append(wasm::MemoryAccess(site.codeOffset, currentOffset()));
+            break;
+          }
+        }
+
+        if (site.trap == wasm::Trap::IndirectCallBadSig) {
+            // The indirect call bad-signature trap is a special case for two
+            // reasons:
+            //  - the check happens in the very first instructions of the
+            //    prologue, before the stack frame has been set up which messes
+            //    up everything (stack depth computations, unwinding)
+            //  - the check happens in the callee while the trap should be
+            //    reported at the caller's call_indirect
+            // To solve both problems at once, the out-of-line path (far) jumps
+            // directly to the trap exit stub. This takes advantage of the fact
+            // that there is already a CallSite for call_indirect and the
+            // current pre-prologue stack/register state.
+            append(wasm::TrapFarJump(site.trap, farJumpWithPatch()));
+        } else {
+            // Inherit the frame depth of the trap site. This value is captured
+            // by the wasm::CallSite to allow unwinding this frame.
+            setFramePushed(site.framePushed);
+
+            // Align the stack for a nullary call.
+            size_t alreadyPushed = sizeof(wasm::Frame) + framePushed();
+            size_t toPush = ABIArgGenerator().stackBytesConsumedSoFar();
+            if (size_t dec = StackDecrementForCall(ABIStackAlignment, alreadyPushed, toPush))
+                reserveStack(dec);
+
+            // Call the trap's exit, using the bytecode offset of the trap site.
+            // Note that this code is inside the same CodeRange::Function as the
+            // trap site so it's as if the trapping instruction called the
+            // trap-handling function. The frame iterator knows to skip the trap
+            // exit's frame so that unwinding begins at the frame and offset of
+            // the trapping instruction.
+            wasm::CallSiteDesc desc(site.bytecodeOffset, wasm::CallSiteDesc::TrapExit);
+            call(desc, site.trap);
+        }
+
+#ifdef DEBUG
+        // Traps do not return, so no need to freeStack().
+        breakpoint();
+#endif
+    }
+
+    // Ensure that the return address of the last emitted call above is always
+    // within this function's CodeRange which is necessary for the stack
+    // iterator to find the right CodeRange while walking the stack.
+    breakpoint();
+
+    clearTrapSites();
+}
+
+//}}} check_macroassembler_style
+
+void
+MacroAssembler::BranchType::emit(MacroAssembler& masm)
+{
+    MOZ_ASSERT(isInitialized());
+    MIRType mirType = MIRType::None;
+
+    if (type_.isPrimitive()) {
+        if (type_.isMagicArguments())
+            mirType = MIRType::MagicOptimizedArguments;
+        else
+            mirType = MIRTypeFromValueType(type_.primitive());
+    } else if (type_.isAnyObject()) {
+        mirType = MIRType::Object;
+    } else {
+        MOZ_CRASH("Unknown conversion to mirtype");
+    }
+
+    if (mirType == MIRType::Double)
+        masm.branchTestNumber(cond(), reg(), jump());
+    else
+        masm.branchTestMIRType(cond(), reg(), mirType, jump());
+}
+
+void
+MacroAssembler::BranchGCPtr::emit(MacroAssembler& masm)
+{
+    MOZ_ASSERT(isInitialized());
+    masm.branchPtr(cond(), reg(), ptr_, jump());
+}
+
+namespace js {
+namespace jit {
+
+#ifdef DEBUG
+template <class RegisterType>
+AutoGenericRegisterScope<RegisterType>::AutoGenericRegisterScope(MacroAssembler& masm, RegisterType reg)
+  : RegisterType(reg), masm_(masm)
+{
+    masm.debugTrackedRegisters_.add(reg);
+}
+
+template AutoGenericRegisterScope<Register>::AutoGenericRegisterScope(MacroAssembler& masm, Register reg);
+template AutoGenericRegisterScope<FloatRegister>::AutoGenericRegisterScope(MacroAssembler& masm, FloatRegister reg);
+#endif // DEBUG
+
+#ifdef DEBUG
+template <class RegisterType>
+AutoGenericRegisterScope<RegisterType>::~AutoGenericRegisterScope()
+{
+    const RegisterType& reg = *dynamic_cast<RegisterType*>(this);
+    masm_.debugTrackedRegisters_.take(reg);
+}
+
+template AutoGenericRegisterScope<Register>::~AutoGenericRegisterScope();
+template AutoGenericRegisterScope<FloatRegister>::~AutoGenericRegisterScope();
+#endif // DEBUG
+
+} // namespace jit
+} // namespace js