Revert #1137 - Remove unboxed arrays

- accounting for removal of watch()/unwatch()
- updated for intermediate code changes.

1 files changed, 117 insertions, 18 deletions

diff --git a/js/src/jit/IonCaches.cpp b/js/src/jit/IonCaches.cpp
index f5e4659c1..c2dc57373 100644
--- a/js/src/jit/IonCaches.cpp
+++ b/js/src/jit/IonCaches.cpp
@@ -639,6 +639,9 @@ TestMatchingReceiver(MacroAssembler& masm, IonCache::StubAttacher& attacher,
         } else {
             masm.branchPtr(Assembler::NotEqual, expandoAddress, ImmWord(0), failure);
         }
+    } else if (obj->is<UnboxedArrayObject>()) {
+        MOZ_ASSERT(failure);
+        masm.branchTestObjGroup(Assembler::NotEqual, object, obj->group(), failure);
     } else if (obj->is<TypedObject>()) {
         attacher.branchNextStubOrLabel(masm, Assembler::NotEqual,
                                        Address(object, JSObject::offsetOfGroup()),
@@ -1185,6 +1188,39 @@ GenerateArrayLength(JSContext* cx, MacroAssembler& masm, IonCache::StubAttacher&
     return true;
 }
 
+static void
+GenerateUnboxedArrayLength(JSContext* cx, MacroAssembler& masm, IonCache::StubAttacher& attacher,
+                           JSObject* array, Register object, TypedOrValueRegister output,
+                           Label* failures)
+{
+    Register outReg;
+    if (output.hasValue()) {
+        outReg = output.valueReg().scratchReg();
+    } else {
+        MOZ_ASSERT(output.type() == MIRType::Int32);
+        outReg = output.typedReg().gpr();
+    }
+    MOZ_ASSERT(object != outReg);
+
+    TestMatchingReceiver(masm, attacher, object, array, failures);
+
+    // Load length.
+    masm.load32(Address(object, UnboxedArrayObject::offsetOfLength()), outReg);
+
+    // Check for a length that fits in an int32.
+    masm.branchTest32(Assembler::Signed, outReg, outReg, failures);
+
+    if (output.hasValue())
+        masm.tagValue(JSVAL_TYPE_INT32, outReg, output.valueReg());
+
+    // Success.
+    attacher.jumpRejoin(masm);
+
+    // Failure.
+    masm.bind(failures);
+    attacher.jumpNextStub(masm);
+}
+
 // In this case, the code for TypedArray and SharedTypedArray is not the same,
 // because the code embeds pointers to the respective class arrays.  Code that
 // caches the stub code must distinguish between the two cases.
@@ -1559,6 +1595,40 @@ GetPropertyIC::tryAttachUnboxedExpando(JSContext* cx, HandleScript outerScript,
 }
 
 bool
+GetPropertyIC::tryAttachUnboxedArrayLength(JSContext* cx, HandleScript outerScript, IonScript* ion,
+                                           HandleObject obj, HandleId id, void* returnAddr,
+                                           bool* emitted)
+{
+    MOZ_ASSERT(canAttachStub());
+    MOZ_ASSERT(!*emitted);
+    MOZ_ASSERT(outerScript->ionScript() == ion);
+
+    if (!obj->is<UnboxedArrayObject>())
+        return true;
+
+    if (!JSID_IS_ATOM(id, cx->names().length))
+        return true;
+
+    if (obj->as<UnboxedArrayObject>().length() > INT32_MAX)
+        return true;
+
+    if (!allowArrayLength(cx))
+        return true;
+
+    *emitted = true;
+
+    MacroAssembler masm(cx, ion, outerScript, profilerLeavePc_);
+
+    Label failures;
+    emitIdGuard(masm, id, &failures);
+
+    StubAttacher attacher(*this);
+    GenerateUnboxedArrayLength(cx, masm, attacher, obj, object(), output(), &failures);
+    return linkAndAttachStub(cx, masm, attacher, ion, "unboxed array length",
+                             JS::TrackedOutcome::ICGetPropStub_UnboxedArrayLength);
+}
+
+bool
 GetPropertyIC::tryAttachTypedArrayLength(JSContext* cx, HandleScript outerScript, IonScript* ion,
                                          HandleObject obj, HandleId id, bool* emitted)
 {
@@ -2133,6 +2203,9 @@ GetPropertyIC::tryAttachStub(JSContext* cx, HandleScript outerScript, IonScript*
         if (!*emitted && !tryAttachUnboxedExpando(cx, outerScript, ion, obj, id, returnAddr, emitted))
             return false;
 
+        if (!*emitted && !tryAttachUnboxedArrayLength(cx, outerScript, ion, obj, id, returnAddr, emitted))
+            return false;
+
         if (!*emitted && !tryAttachTypedArrayLength(cx, outerScript, ion, obj, id, emitted))
             return false;
     }
@@ -3953,7 +4026,7 @@ GetPropertyIC::tryAttachDenseElementHole(JSContext* cx, HandleScript outerScript
 GetPropertyIC::canAttachTypedOrUnboxedArrayElement(JSObject* obj, const Value& idval,
                                                    TypedOrValueRegister output)
 {
-    if (!obj->is<TypedArrayObject>())
+    if (!obj->is<TypedArrayObject>() && !obj->is<UnboxedArrayObject>())
         return false;
 
     MOZ_ASSERT(idval.isInt32() || idval.isString());
@@ -3984,6 +4057,13 @@ GetPropertyIC::canAttachTypedOrUnboxedArrayElement(JSObject* obj, const Value& i
         return output.hasValue() || !output.typedReg().isFloat();
     }
 
+    if (index >= obj->as<UnboxedArrayObject>().initializedLength())
+        return false;
+
+    JSValueType elementType = obj->as<UnboxedArrayObject>().elementType();
+    if (elementType == JSVAL_TYPE_DOUBLE)
+        return output.hasValue();
+
     return output.hasValue() || !output.typedReg().isFloat();
 }
 
@@ -4060,27 +4140,46 @@ GenerateGetTypedOrUnboxedArrayElement(JSContext* cx, MacroAssembler& masm,
 
     Label popObjectAndFail;
 
-    // Guard on the initialized length.
-    Address length(object, TypedArrayObject::lengthOffset());
-    masm.branch32(Assembler::BelowOrEqual, length, indexReg, &failures);
+    if (array->is<TypedArrayObject>()) {
+        // Guard on the initialized length.
+        Address length(object, TypedArrayObject::lengthOffset());
+        masm.branch32(Assembler::BelowOrEqual, length, indexReg, &failures);
 
-    // Save the object register on the stack in case of failure.
-    Register elementReg = object;
-    masm.push(object);
+        // Save the object register on the stack in case of failure.
+        Register elementReg = object;
+        masm.push(object);
 
-    // Load elements vector.
-    masm.loadPtr(Address(object, TypedArrayObject::dataOffset()), elementReg);
+        // Load elements vector.
+        masm.loadPtr(Address(object, TypedArrayObject::dataOffset()), elementReg);
 
-    // Load the value. We use an invalid register because the destination
-    // register is necessary a non double register.
-    Scalar::Type arrayType = array->as<TypedArrayObject>().type();
-    int width = Scalar::byteSize(arrayType);
-    BaseIndex source(elementReg, indexReg, ScaleFromElemWidth(width));
-    if (output.hasValue()) {
-        masm.loadFromTypedArray(arrayType, source, output.valueReg(), allowDoubleResult,
-                                elementReg, &popObjectAndFail);
+        // Load the value. We use an invalid register because the destination
+        // register is necessary a non double register.
+        Scalar::Type arrayType = array->as<TypedArrayObject>().type();
+        int width = Scalar::byteSize(arrayType);
+        BaseIndex source(elementReg, indexReg, ScaleFromElemWidth(width));
+        if (output.hasValue()) {
+            masm.loadFromTypedArray(arrayType, source, output.valueReg(), allowDoubleResult,
+                                    elementReg, &popObjectAndFail);
+        } else {
+            masm.loadFromTypedArray(arrayType, source, output.typedReg(), elementReg, &popObjectAndFail);
+        }
     } else {
-        masm.loadFromTypedArray(arrayType, source, output.typedReg(), elementReg, &popObjectAndFail);
+        // Save the object register on the stack in case of failure.
+        masm.push(object);
+
+        // Guard on the initialized length.
+        masm.load32(Address(object, UnboxedArrayObject::offsetOfCapacityIndexAndInitializedLength()), object);
+        masm.and32(Imm32(UnboxedArrayObject::InitializedLengthMask), object);
+        masm.branch32(Assembler::BelowOrEqual, object, indexReg, &popObjectAndFail);
+
+        // Load elements vector.
+        Register elementReg = object;
+        masm.loadPtr(Address(masm.getStackPointer(), 0), object);
+        masm.loadPtr(Address(object, UnboxedArrayObject::offsetOfElements()), elementReg);
+
+        JSValueType elementType = array->as<UnboxedArrayObject>().elementType();
+        BaseIndex source(elementReg, indexReg, ScaleFromElemWidth(UnboxedTypeSize(elementType)));
+        masm.loadUnboxedProperty(source, elementType, output);
     }
 
     masm.pop(object);