The Tor Browser: js/src/builtin/TypedObject.js@6474c204b198 (annotated)

js/src/builtin/TypedObject.js@6474c204b198 (annotated)

js/src/builtin/TypedObject.js

Wed, 31 Dec 2014 06:09:35 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Wed, 31 Dec 2014 06:09:35 +0100
changeset 0: 6474c204b198
permissions: -rw-r--r--

Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.

 #include "TypedObjectConstants.h"
 ///////////////////////////////////////////////////////////////////////////
 // Getters and setters for various slots.
 // Type object slots
 #define DESCR_KIND(obj) \
     UnsafeGetReservedSlot(obj, JS_DESCR_SLOT_KIND)
 #define DESCR_STRING_REPR(obj) \
     UnsafeGetReservedSlot(obj, JS_DESCR_SLOT_STRING_REPR)
 #define DESCR_ALIGNMENT(obj) \
     UnsafeGetReservedSlot(obj, JS_DESCR_SLOT_ALIGNMENT)
 #define DESCR_SIZE(obj) \
     UnsafeGetReservedSlot(obj, JS_DESCR_SLOT_SIZE)
 #define DESCR_OPAQUE(obj) \
     UnsafeGetReservedSlot(obj, JS_DESCR_SLOT_OPAQUE)
 #define DESCR_TYPE(obj)   \
     UnsafeGetReservedSlot(obj, JS_DESCR_SLOT_TYPE)
 #define DESCR_ARRAY_ELEMENT_TYPE(obj) \
     UnsafeGetReservedSlot(obj, JS_DESCR_SLOT_ARRAY_ELEM_TYPE)
 #define DESCR_SIZED_ARRAY_LENGTH(obj) \
     TO_INT32(UnsafeGetReservedSlot(obj, JS_DESCR_SLOT_SIZED_ARRAY_LENGTH))
 #define DESCR_STRUCT_FIELD_NAMES(obj) \
     UnsafeGetReservedSlot(obj, JS_DESCR_SLOT_STRUCT_FIELD_NAMES)
 #define DESCR_STRUCT_FIELD_TYPES(obj) \
     UnsafeGetReservedSlot(obj, JS_DESCR_SLOT_STRUCT_FIELD_TYPES)
 #define DESCR_STRUCT_FIELD_OFFSETS(obj) \
     UnsafeGetReservedSlot(obj, JS_DESCR_SLOT_STRUCT_FIELD_OFFSETS)
 // Typed object slots
 #define TYPEDOBJ_BYTEOFFSET(obj) \
     TO_INT32(UnsafeGetReservedSlot(obj, JS_TYPEDOBJ_SLOT_BYTEOFFSET))
 #define TYPEDOBJ_BYTELENGTH(obj) \
     TO_INT32(UnsafeGetReservedSlot(obj, JS_TYPEDOBJ_SLOT_BYTELENGTH))
 #define TYPEDOBJ_TYPE_DESCR(obj) \
     UnsafeGetReservedSlot(obj, JS_TYPEDOBJ_SLOT_TYPE_DESCR)
 #define TYPEDOBJ_OWNER(obj) \
     UnsafeGetReservedSlot(obj, JS_TYPEDOBJ_SLOT_OWNER)
 #define TYPEDOBJ_LENGTH(obj) \
     TO_INT32(UnsafeGetReservedSlot(obj, JS_TYPEDOBJ_SLOT_LENGTH))
 #define HAS_PROPERTY(obj, prop) \
     callFunction(std_Object_hasOwnProperty, obj, prop)
 ///////////////////////////////////////////////////////////////////////////
 // Getting values
 //
 // The methods in this section read from the memory pointed at
 // by `this` and produce JS values. This process is called *reification*
 // in the spec.
 // Reifies the value referenced by the pointer, meaning that it
 // returns a new object pointing at the value. If the value is
 // a scalar, it will return a JS number, but otherwise the reified
 // result will be a typedObj of the same class as the ptr's typedObj.
 function TypedObjectGet(descr, typedObj, offset) {
   assert(IsObject(descr) && ObjectIsTypeDescr(descr),
          "get() called with bad type descr");
   assert(TypedObjectIsAttached(typedObj),
          "get() called with unattached typedObj");
   switch (DESCR_KIND(descr)) {
   case JS_TYPEREPR_SCALAR_KIND:
     return TypedObjectGetScalar(descr, typedObj, offset);
   case JS_TYPEREPR_REFERENCE_KIND:
     return TypedObjectGetReference(descr, typedObj, offset);
   case JS_TYPEREPR_X4_KIND:
     return TypedObjectGetX4(descr, typedObj, offset);
   case JS_TYPEREPR_SIZED_ARRAY_KIND:
   case JS_TYPEREPR_STRUCT_KIND:
     return TypedObjectGetDerived(descr, typedObj, offset);
   case JS_TYPEREPR_UNSIZED_ARRAY_KIND:
     assert(false, "Unhandled repr kind: " + DESCR_KIND(descr));
   }
   assert(false, "Unhandled kind: " + DESCR_KIND(descr));
   return undefined;
 }
 function TypedObjectGetDerived(descr, typedObj, offset) {
   assert(!TypeDescrIsSimpleType(descr),
          "getDerived() used with simple type");
   return NewDerivedTypedObject(descr, typedObj, offset);
 }
 function TypedObjectGetDerivedIf(descr, typedObj, offset, cond) {
   return (cond ? TypedObjectGetDerived(descr, typedObj, offset) : undefined);
 }
 function TypedObjectGetOpaque(descr, typedObj, offset) {
   assert(!TypeDescrIsSimpleType(descr),
          "getDerived() used with simple type");
   var opaqueTypedObj = NewOpaqueTypedObject(descr);
   AttachTypedObject(opaqueTypedObj, typedObj, offset);
   return opaqueTypedObj;
 }
 function TypedObjectGetOpaqueIf(descr, typedObj, offset, cond) {
   return (cond ? TypedObjectGetOpaque(descr, typedObj, offset) : undefined);
 }
 function TypedObjectGetScalar(descr, typedObj, offset) {
   var type = DESCR_TYPE(descr);
   switch (type) {
   case JS_SCALARTYPEREPR_INT8:
     return Load_int8(typedObj, offset);
   case JS_SCALARTYPEREPR_UINT8:
   case JS_SCALARTYPEREPR_UINT8_CLAMPED:
     return Load_uint8(typedObj, offset);
   case JS_SCALARTYPEREPR_INT16:
     return Load_int16(typedObj, offset);
   case JS_SCALARTYPEREPR_UINT16:
     return Load_uint16(typedObj, offset);
   case JS_SCALARTYPEREPR_INT32:
     return Load_int32(typedObj, offset);
   case JS_SCALARTYPEREPR_UINT32:
     return Load_uint32(typedObj, offset);
   case JS_SCALARTYPEREPR_FLOAT32:
     return Load_float32(typedObj, offset);
   case JS_SCALARTYPEREPR_FLOAT64:
     return Load_float64(typedObj, offset);
   }
   assert(false, "Unhandled scalar type: " + type);
   return undefined;
 }
 function TypedObjectGetReference(descr, typedObj, offset) {
   var type = DESCR_TYPE(descr);
   switch (type) {
   case JS_REFERENCETYPEREPR_ANY:
     return Load_Any(typedObj, offset);
   case JS_REFERENCETYPEREPR_OBJECT:
     return Load_Object(typedObj, offset);
   case JS_REFERENCETYPEREPR_STRING:
     return Load_string(typedObj, offset);
   }
   assert(false, "Unhandled scalar type: " + type);
   return undefined;
 }
 function TypedObjectGetX4(descr, typedObj, offset) {
   var type = DESCR_TYPE(descr);
   switch (type) {
   case JS_X4TYPEREPR_FLOAT32:
     var x = Load_float32(typedObj, offset + 0);
     var y = Load_float32(typedObj, offset + 4);
     var z = Load_float32(typedObj, offset + 8);
     var w = Load_float32(typedObj, offset + 12);
     return GetFloat32x4TypeDescr()(x, y, z, w);
   case JS_X4TYPEREPR_INT32:
     var x = Load_int32(typedObj, offset + 0);
     var y = Load_int32(typedObj, offset + 4);
     var z = Load_int32(typedObj, offset + 8);
     var w = Load_int32(typedObj, offset + 12);
     return GetInt32x4TypeDescr()(x, y, z, w);
   }
   assert(false, "Unhandled x4 type: " + type);
   return undefined;
 }
 ///////////////////////////////////////////////////////////////////////////
 // Setting values
 //
 // The methods in this section modify the data pointed at by `this`.
 // Writes `fromValue` into the `typedObj` at offset `offset`, adapting
 // it to `descr` as needed. This is the most general entry point
 // and works for any type.
 function TypedObjectSet(descr, typedObj, offset, fromValue) {
   assert(TypedObjectIsAttached(typedObj), "set() called with unattached typedObj");
   // Fast path: `fromValue` is a typed object with same type
   // representation as the destination. In that case, we can just do a
   // memcpy.
   if (IsObject(fromValue) && ObjectIsTypedObject(fromValue)) {
     if (!descr.variable && DescrsEquiv(descr, TYPEDOBJ_TYPE_DESCR(fromValue))) {
       if (!TypedObjectIsAttached(fromValue))
         ThrowError(JSMSG_TYPEDOBJECT_HANDLE_UNATTACHED);
       var size = DESCR_SIZE(descr);
       Memcpy(typedObj, offset, fromValue, 0, size);
       return;
     }
   }
   switch (DESCR_KIND(descr)) {
   case JS_TYPEREPR_SCALAR_KIND:
     TypedObjectSetScalar(descr, typedObj, offset, fromValue);
     return;
   case JS_TYPEREPR_REFERENCE_KIND:
     TypedObjectSetReference(descr, typedObj, offset, fromValue);
     return;
   case JS_TYPEREPR_X4_KIND:
     TypedObjectSetX4(descr, typedObj, offset, fromValue);
     return;
   case JS_TYPEREPR_SIZED_ARRAY_KIND:
     var length = DESCR_SIZED_ARRAY_LENGTH(descr);
     if (TypedObjectSetArray(descr, length, typedObj, offset, fromValue))
       return;
     break;
   case JS_TYPEREPR_UNSIZED_ARRAY_KIND:
     var length = typedObj.length;
     if (TypedObjectSetArray(descr, length, typedObj, offset, fromValue))
       return;
     break;
   case JS_TYPEREPR_STRUCT_KIND:
     if (!IsObject(fromValue))
       break;
     // Adapt each field.
     var fieldNames = DESCR_STRUCT_FIELD_NAMES(descr);
     var fieldDescrs = DESCR_STRUCT_FIELD_TYPES(descr);
     var fieldOffsets = DESCR_STRUCT_FIELD_OFFSETS(descr);
     for (var i = 0; i < fieldNames.length; i++) {
       var fieldName = fieldNames[i];
       var fieldDescr = fieldDescrs[i];
       var fieldOffset = fieldOffsets[i];
       var fieldValue = fromValue[fieldName];
       TypedObjectSet(fieldDescr, typedObj, offset + fieldOffset, fieldValue);
     }
     return;
   }
   ThrowError(JSMSG_CANT_CONVERT_TO,
              typeof(fromValue),
              DESCR_STRING_REPR(descr));
 }
 function TypedObjectSetArray(descr, length, typedObj, offset, fromValue) {
   if (!IsObject(fromValue))
     return false;
   // Check that "array-like" fromValue has an appropriate length.
   if (fromValue.length !== length)
     return false;
   // Adapt each element.
   if (length > 0) {
     var elemDescr = DESCR_ARRAY_ELEMENT_TYPE(descr);
     var elemSize = DESCR_SIZE(elemDescr);
     var elemOffset = offset;
     for (var i = 0; i < length; i++) {
       TypedObjectSet(elemDescr, typedObj, elemOffset, fromValue[i]);
       elemOffset += elemSize;
     }
   }
   return true;
 }
 // Sets `fromValue` to `this` assuming that `this` is a scalar type.
 function TypedObjectSetScalar(descr, typedObj, offset, fromValue) {
   assert(DESCR_KIND(descr) === JS_TYPEREPR_SCALAR_KIND,
          "Expected scalar type descriptor");
   var type = DESCR_TYPE(descr);
   switch (type) {
   case JS_SCALARTYPEREPR_INT8:
     return Store_int8(typedObj, offset,
                      TO_INT32(fromValue) & 0xFF);
   case JS_SCALARTYPEREPR_UINT8:
     return Store_uint8(typedObj, offset,
                       TO_UINT32(fromValue) & 0xFF);
   case JS_SCALARTYPEREPR_UINT8_CLAMPED:
     var v = ClampToUint8(+fromValue);
     return Store_int8(typedObj, offset, v);
   case JS_SCALARTYPEREPR_INT16:
     return Store_int16(typedObj, offset,
                       TO_INT32(fromValue) & 0xFFFF);
   case JS_SCALARTYPEREPR_UINT16:
     return Store_uint16(typedObj, offset,
                        TO_UINT32(fromValue) & 0xFFFF);
   case JS_SCALARTYPEREPR_INT32:
     return Store_int32(typedObj, offset,
                       TO_INT32(fromValue));
   case JS_SCALARTYPEREPR_UINT32:
     return Store_uint32(typedObj, offset,
                        TO_UINT32(fromValue));
   case JS_SCALARTYPEREPR_FLOAT32:
     return Store_float32(typedObj, offset, +fromValue);
   case JS_SCALARTYPEREPR_FLOAT64:
     return Store_float64(typedObj, offset, +fromValue);
   }
   assert(false, "Unhandled scalar type: " + type);
   return undefined;
 }
 function TypedObjectSetReference(descr, typedObj, offset, fromValue) {
   var type = DESCR_TYPE(descr);
   switch (type) {
   case JS_REFERENCETYPEREPR_ANY:
     return Store_Any(typedObj, offset, fromValue);
   case JS_REFERENCETYPEREPR_OBJECT:
     var value = (fromValue === null ? fromValue : ToObject(fromValue));
     return Store_Object(typedObj, offset, value);
   case JS_REFERENCETYPEREPR_STRING:
     return Store_string(typedObj, offset, ToString(fromValue));
   }
   assert(false, "Unhandled scalar type: " + type);
   return undefined;
 }
 // Sets `fromValue` to `this` assuming that `this` is a scalar type.
 function TypedObjectSetX4(descr, typedObj, offset, fromValue) {
   // It is only permitted to set a float32x4/int32x4 value from another
   // float32x4/int32x4; in that case, the "fast path" that uses memcopy will
   // have already matched. So if we get to this point, we're supposed
   // to "adapt" fromValue, but there are no legal adaptions.
   ThrowError(JSMSG_CANT_CONVERT_TO,
              typeof(fromValue),
              DESCR_STRING_REPR(descr));
 }
 ///////////////////////////////////////////////////////////////////////////
 // C++ Wrappers
 //
 // These helpers are invoked by C++ code or used as method bodies.
 // Wrapper for use from C++ code.
 function ConvertAndCopyTo(destDescr,
                           destTypedObj,
                           destOffset,
                           fromValue)
 {
   assert(IsObject(destDescr) && ObjectIsTypeDescr(destDescr),
          "ConvertAndCopyTo: not type obj");
   assert(IsObject(destTypedObj) && ObjectIsTypedObject(destTypedObj),
          "ConvertAndCopyTo: not type typedObj");
   if (!TypedObjectIsAttached(destTypedObj))
     ThrowError(JSMSG_TYPEDOBJECT_HANDLE_UNATTACHED);
   TypedObjectSet(destDescr, destTypedObj, destOffset, fromValue);
 }
 // Wrapper for use from C++ code.
 function Reify(sourceDescr,
                sourceTypedObj,
                sourceOffset) {
   assert(IsObject(sourceDescr) && ObjectIsTypeDescr(sourceDescr),
          "Reify: not type obj");
   assert(IsObject(sourceTypedObj) && ObjectIsTypedObject(sourceTypedObj),
          "Reify: not type typedObj");
   if (!TypedObjectIsAttached(sourceTypedObj))
     ThrowError(JSMSG_TYPEDOBJECT_HANDLE_UNATTACHED);
   return TypedObjectGet(sourceDescr, sourceTypedObj, sourceOffset);
 }
 function FillTypedArrayWithValue(destArray, fromValue) {
   assert(IsObject(handle) && ObjectIsTypedObject(destArray),
          "FillTypedArrayWithValue: not typed handle");
   var descr = TYPEDOBJ_TYPE_DESCR(destArray);
   var length = DESCR_SIZED_ARRAY_LENGTH(descr);
   if (length === 0)
     return;
   // Use convert and copy to to produce the first element:
   var elemDescr = DESCR_ARRAY_ELEMENT_TYPE(descr);
   TypedObjectSet(elemDescr, destArray, 0, fromValue);
   // Stamp out the remaining copies:
   var elemSize = DESCR_SIZE(elemDescr);
   var totalSize = length * elemSize;
   for (var offset = elemSize; offset < totalSize; offset += elemSize)
     Memcpy(destArray, offset, destArray, 0, elemSize);
 }
 // Warning: user exposed!
 function TypeDescrEquivalent(otherDescr) {
   if (!IsObject(this) || !ObjectIsTypeDescr(this))
     ThrowError(JSMSG_TYPEDOBJECT_BAD_ARGS);
   if (!IsObject(otherDescr) || !ObjectIsTypeDescr(otherDescr))
     ThrowError(JSMSG_TYPEDOBJECT_BAD_ARGS);
   return DescrsEquiv(this, otherDescr);
 }
 // TypedArray.redimension(newArrayType)
 //
 // Method that "repackages" the data from this array into a new typed
 // object whose type is `newArrayType`. Once you strip away all the
 // outer array dimensions, the type of `this` array and `newArrayType`
 // must share the same innermost element type. Moreover, those
 // stripped away dimensions must amount to the same total number of
 // elements.
 //
 // For example, given two equivalent types `T` and `U`, it is legal to
 // interconvert between arrays types like:
 //     T[32]
 //     U[2][16]
 //     U[2][2][8]
 // Because they all share the same total number (32) of equivalent elements.
 // But it would be illegal to convert `T[32]` to `U[31]` or `U[2][17]`, since
 // the number of elements differs. And it's just plain incompatible to convert
 // if the base element types are not equivalent.
 //
 // Warning: user exposed!
 function TypedArrayRedimension(newArrayType) {
   if (!IsObject(this) || !ObjectIsTypedObject(this))
     ThrowError(JSMSG_TYPEDOBJECT_BAD_ARGS);
   if (!IsObject(newArrayType) || !ObjectIsTypeDescr(newArrayType))
     ThrowError(JSMSG_TYPEDOBJECT_BAD_ARGS);
   // Peel away the outermost array layers from the type of `this` to find
   // the core element type. In the process, count the number of elements.
   var oldArrayType = TYPEDOBJ_TYPE_DESCR(this);
   var oldArrayReprKind = DESCR_KIND(oldArrayType);
   var oldElementType = oldArrayType;
   var oldElementCount = 1;
   switch (oldArrayReprKind) {
   case JS_TYPEREPR_UNSIZED_ARRAY_KIND:
     oldElementCount *= this.length;
     oldElementType = oldElementType.elementType;
     break;
   case JS_TYPEREPR_SIZED_ARRAY_KIND:
     break;
   default:
     ThrowError(JSMSG_TYPEDOBJECT_BAD_ARGS);
   }
   while (DESCR_KIND(oldElementType) === JS_TYPEREPR_SIZED_ARRAY_KIND) {
     oldElementCount *= oldElementType.length;
     oldElementType = oldElementType.elementType;
   }
   // Peel away the outermost array layers from `newArrayType`. In the
   // process, count the number of elements.
   var newElementType = newArrayType;
   var newElementCount = 1;
   while (DESCR_KIND(newElementType) == JS_TYPEREPR_SIZED_ARRAY_KIND) {
     newElementCount *= newElementType.length;
     newElementType = newElementType.elementType;
   }
   // Check that the total number of elements does not change.
   if (oldElementCount !== newElementCount) {
     ThrowError(JSMSG_TYPEDOBJECT_BAD_ARGS);
   }
   // Check that the element types are equivalent.
   if (!DescrsEquiv(oldElementType, newElementType)) {
     ThrowError(JSMSG_TYPEDOBJECT_BAD_ARGS);
   }
   // Together, this should imply that the sizes are unchanged.
   assert(DESCR_SIZE(oldArrayType) == DESCR_SIZE(newArrayType),
          "Byte sizes should be equal");
   // Rewrap the data from `this` in a new type.
   return NewDerivedTypedObject(newArrayType, this, 0);
 }
 ///////////////////////////////////////////////////////////////////////////
 // X4
 function X4ProtoString(type) {
   switch (type) {
   case JS_X4TYPEREPR_INT32:
     return "int32x4";
   case JS_X4TYPEREPR_FLOAT32:
     return "float32x4";
   }
   assert(false, "Unhandled type constant");
   return undefined;
 }
 function X4ToSource() {
   if (!IsObject(this) || !ObjectIsTypedObject(this))
     ThrowError(JSMSG_INCOMPATIBLE_PROTO, "X4", "toSource", typeof this);
   var descr = TYPEDOBJ_TYPE_DESCR(this);
   if (DESCR_KIND(descr) != JS_TYPEREPR_X4_KIND)
     ThrowError(JSMSG_INCOMPATIBLE_PROTO, "X4", "toSource", typeof this);
   var type = DESCR_TYPE(descr);
   return X4ProtoString(type)+"("+this.x+", "+this.y+", "+this.z+", "+this.w+")";
 }
 ///////////////////////////////////////////////////////////////////////////
 // Miscellaneous
 function DescrsEquiv(descr1, descr2) {
   assert(IsObject(descr1) && ObjectIsTypeDescr(descr1), "descr1 not descr");
   assert(IsObject(descr2) && ObjectIsTypeDescr(descr2), "descr2 not descr");
   // Potential optimization: these two strings are guaranteed to be
   // atoms, and hence this string comparison can just be a pointer
   // comparison.  However, I don't think ion knows that. If this ever
   // becomes a bottleneck, we can add a intrinsic at some point that
   // is treated specially by Ion.  (Bug 976688)
   return DESCR_STRING_REPR(descr1) === DESCR_STRING_REPR(descr2);
 }
 // toSource() for type descriptors.
 //
 // Warning: user exposed!
 function DescrToSource() {
   if (!IsObject(this) || !ObjectIsTypeDescr(this))
     ThrowError(JSMSG_INCOMPATIBLE_PROTO, "Type", "toSource", "value");
   return DESCR_STRING_REPR(this);
 }
 // Warning: user exposed!
 function ArrayShorthand(...dims) {
   if (!IsObject(this) || !ObjectIsTypeDescr(this))
     ThrowError(JSMSG_TYPEDOBJECT_BAD_ARGS);
   var T = GetTypedObjectModule();
   if (dims.length == 0)
     return new T.ArrayType(this);
   var accum = this;
   for (var i = dims.length - 1; i >= 0; i--)
     accum = new T.ArrayType(accum).dimension(dims[i]);
   return accum;
 }
 // This is the `storage()` function defined in the spec.  When
 // provided with a *transparent* typed object, it returns an object
 // containing buffer, byteOffset, byteLength. When given an opaque
 // typed object, it returns null. Otherwise it throws.
 //
 // Warning: user exposed!
 function StorageOfTypedObject(obj) {
   if (IsObject(obj)) {
     if (ObjectIsOpaqueTypedObject(obj))
       return null;
     if (ObjectIsTransparentTypedObject(obj))
       return { buffer: TYPEDOBJ_OWNER(obj),
                byteLength: TYPEDOBJ_BYTELENGTH(obj),
                byteOffset: TYPEDOBJ_BYTEOFFSET(obj) };
   }
   ThrowError(JSMSG_TYPEDOBJECT_BAD_ARGS);
   return null; // pacify silly "always returns a value" lint
 }
 // This is the `objectType()` function defined in the spec.
 // It returns the type of its argument.
 //
 // Warning: user exposed!
 function TypeOfTypedObject(obj) {
   if (IsObject(obj) && ObjectIsTypedObject(obj))
     return TYPEDOBJ_TYPE_DESCR(obj);
   // Note: Do not create bindings for `Any`, `String`, etc in
   // Utilities.js, but rather access them through
   // `GetTypedObjectModule()`. The reason is that bindings
   // you create in Utilities.js are part of the self-hosted global,
   // vs the user-accessible global, and hence should not escape to
   // user script.
   var T = GetTypedObjectModule();
   switch (typeof obj) {
     case "object": return T.Object;
     case "function": return T.Object;
     case "string": return T.String;
     case "number": return T.float64;
     case "undefined": return T.Any;
     default: return T.Any;
   }
 }
 ///////////////////////////////////////////////////////////////////////////
 // TypedObject surface API methods (sequential implementations).
 // Warning: user exposed!
 function TypedObjectArrayTypeBuild(a,b,c) {
   // Arguments (this sized) : [depth], func
   // Arguments (this unsized) : length, [depth], func
   if (!IsObject(this) || !ObjectIsTypeDescr(this))
     ThrowError(JSMSG_TYPEDOBJECT_BAD_ARGS);
   var kind = DESCR_KIND(this);
   switch (kind) {
   case JS_TYPEREPR_SIZED_ARRAY_KIND:
     if (typeof a === "function") // XXX here and elsewhere: these type dispatches are fragile at best.
       return BuildTypedSeqImpl(this, this.length, 1, a);
     else if (typeof a === "number" && typeof b === "function")
       return BuildTypedSeqImpl(this, this.length, a, b);
     else if (typeof a === "number")
       return ThrowError(JSMSG_TYPEDOBJECT_BAD_ARGS);
     else
       return ThrowError(JSMSG_TYPEDOBJECT_BAD_ARGS);
   case JS_TYPEREPR_UNSIZED_ARRAY_KIND:
     var len = a;
     if (typeof b === "function")
       return BuildTypedSeqImpl(this, len, 1, b);
     else if (typeof b === "number" && typeof c === "function")
       return BuildTypedSeqImpl(this, len, b, c);
     else if (typeof b === "number")
       return ThrowError(JSMSG_TYPEDOBJECT_BAD_ARGS);
     else
       return ThrowError(JSMSG_TYPEDOBJECT_BAD_ARGS);
   default:
     return ThrowError(JSMSG_TYPEDOBJECT_BAD_ARGS);
   }
 }
 // Warning: user exposed!
 function TypedObjectArrayTypeFrom(a, b, c) {
   // Arguments: arrayLike, [depth], func
   if (!IsObject(this) || !ObjectIsTypeDescr(this))
     ThrowError(JSMSG_TYPEDOBJECT_BAD_ARGS);
   var untypedInput = !IsObject(a) || !ObjectIsTypedObject(a);
   // for untyped input array, the expectation (in terms of error
   // reporting for invalid parameters) is no-depth, despite
   // supporting an explicit depth of 1; while for typed input array,
   // the expectation is explicit depth.
   if (untypedInput) {
     var explicitDepth = (b === 1);
     if (explicitDepth && IsCallable(c))
       return MapUntypedSeqImpl(a, this, c);
     else if (IsCallable(b))
       return MapUntypedSeqImpl(a, this, b);
     else
       return ThrowError(JSMSG_TYPEDOBJECT_BAD_ARGS);
   } else {
     var explicitDepth = (typeof b === "number");
     if (explicitDepth && IsCallable(c))
       return MapTypedSeqImpl(a, b, this, c);
     else if (IsCallable(b))
       return MapTypedSeqImpl(a, 1, this, b);
     else if (explicitDepth)
       return ThrowError(JSMSG_TYPEDOBJECT_BAD_ARGS);
     else
       return ThrowError(JSMSG_TYPEDOBJECT_BAD_ARGS);
   }
 }
 // Warning: user exposed!
 function TypedArrayMap(a, b) {
   if (!IsObject(this) || !ObjectIsTypedObject(this))
     return ThrowError(JSMSG_TYPEDOBJECT_BAD_ARGS);
   var thisType = TYPEDOBJ_TYPE_DESCR(this);
   if (!TypeDescrIsArrayType(thisType))
     return ThrowError(JSMSG_TYPEDOBJECT_BAD_ARGS);
   // Arguments: [depth], func
   if (typeof a === "number" && typeof b === "function")
     return MapTypedSeqImpl(this, a, thisType, b);
   else if (typeof a === "function")
     return MapTypedSeqImpl(this, 1, thisType, a);
   return ThrowError(JSMSG_TYPEDOBJECT_BAD_ARGS);
 }
 // Warning: user exposed!
 function TypedArrayMapPar(a, b) {
   // Arguments: [depth], func
   // Defer to the sequential variant for error cases or
   // when not working with typed objects.
   if (!IsObject(this) || !ObjectIsTypedObject(this))
     return callFunction(TypedArrayMap, this, a, b);
   var thisType = TYPEDOBJ_TYPE_DESCR(this);
   if (!TypeDescrIsArrayType(thisType))
     return callFunction(TypedArrayMap, this, a, b);
   if (typeof a === "number" && IsCallable(b))
     return MapTypedParImpl(this, a, thisType, b);
   else if (IsCallable(a))
     return MapTypedParImpl(this, 1, thisType, a);
   return callFunction(TypedArrayMap, this, a, b);
 }
 // Warning: user exposed!
 function TypedArrayReduce(a, b) {
   // Arguments: func, [initial]
   if (!IsObject(this) || !ObjectIsTypedObject(this))
     return ThrowError(JSMSG_TYPEDOBJECT_BAD_ARGS);
   var thisType = TYPEDOBJ_TYPE_DESCR(this);
   if (!TypeDescrIsArrayType(thisType))
     return ThrowError(JSMSG_TYPEDOBJECT_BAD_ARGS);
   if (a !== undefined && typeof a !== "function")
     return ThrowError(JSMSG_TYPEDOBJECT_BAD_ARGS);
   var outputType = thisType.elementType;
   return ReduceTypedSeqImpl(this, outputType, a, b);
 }
 // Warning: user exposed!
 function TypedArrayScatter(a, b, c, d) {
   // Arguments: outputArrayType, indices, defaultValue, conflictFunction
   if (!IsObject(this) || !ObjectIsTypedObject(this))
     return ThrowError(JSMSG_TYPEDOBJECT_BAD_ARGS);
   var thisType = TYPEDOBJ_TYPE_DESCR(this);
   if (!TypeDescrIsArrayType(thisType))
     return ThrowError(JSMSG_TYPEDOBJECT_BAD_ARGS);
   if (!IsObject(a) || !ObjectIsTypeDescr(a) || !TypeDescrIsSizedArrayType(a))
     return ThrowError(JSMSG_TYPEDOBJECT_BAD_ARGS);
   if (d !== undefined && typeof d !== "function")
     return ThrowError(JSMSG_TYPEDOBJECT_BAD_ARGS);
   return ScatterTypedSeqImpl(this, a, b, c, d);
 }
 // Warning: user exposed!
 function TypedArrayFilter(func) {
   // Arguments: predicate
   if (!IsObject(this) || !ObjectIsTypedObject(this))
     return ThrowError(JSMSG_TYPEDOBJECT_BAD_ARGS);
   var thisType = TYPEDOBJ_TYPE_DESCR(this);
   if (!TypeDescrIsArrayType(thisType))
     return ThrowError(JSMSG_TYPEDOBJECT_BAD_ARGS);
   if (typeof func !== "function")
     return ThrowError(JSMSG_TYPEDOBJECT_BAD_ARGS);
   return FilterTypedSeqImpl(this, func);
 }
 // placeholders
 // Warning: user exposed!
 function TypedObjectArrayTypeBuildPar(a,b,c) {
   return callFunction(TypedObjectArrayTypeBuild, this, a, b, c);
 }
 // Warning: user exposed!
 function TypedObjectArrayTypeFromPar(a,b,c) {
   // Arguments: arrayLike, [depth], func
   // Use the sequential version for error cases or when arrayLike is
   // not a typed object.
   if (!IsObject(this) || !ObjectIsTypeDescr(this) || !TypeDescrIsArrayType(this))
     return callFunction(TypedObjectArrayTypeFrom, this, a, b, c);
   if (!IsObject(a) || !ObjectIsTypedObject(a))
     return callFunction(TypedObjectArrayTypeFrom, this, a, b, c);
   // Detect whether an explicit depth is supplied.
   if (typeof b === "number" && IsCallable(c))
     return MapTypedParImpl(a, b, this, c);
   if (IsCallable(b))
     return MapTypedParImpl(a, 1, this, b);
   return callFunction(TypedObjectArrayTypeFrom, this, a, b, c);
 }
 // Warning: user exposed!
 function TypedArrayReducePar(a, b) {
   return callFunction(TypedArrayReduce, this, a, b);
 }
 // Warning: user exposed!
 function TypedArrayScatterPar(a, b, c, d) {
   return callFunction(TypedArrayScatter, this, a, b, c, d);
 }
 // Warning: user exposed!
 function TypedArrayFilterPar(func) {
   return callFunction(TypedArrayFilter, this, func);
 }
 // should eventually become macros
 function NUM_BYTES(bits) {
   return (bits + 7) >> 3;
 }
 function SET_BIT(data, index) {
   var word = index >> 3;
   var mask = 1 << (index & 0x7);
   data[word] |= mask;
 }
 function GET_BIT(data, index) {
   var word = index >> 3;
   var mask = 1 << (index & 0x7);
   return (data[word] & mask) != 0;
 }
 // Bug 956914: make performance-tuned variants tailored to 1, 2, and 3 dimensions.
 function BuildTypedSeqImpl(arrayType, len, depth, func) {
   assert(IsObject(arrayType) && ObjectIsTypeDescr(arrayType), "Build called on non-type-object");
   if (depth <= 0 || TO_INT32(depth) !== depth)
     // RangeError("bad depth")
     ThrowError(JSMSG_TYPEDOBJECT_BAD_ARGS);
   // For example, if we have as input
   //    ArrayType(ArrayType(T, 4), 5)
   // and a depth of 2, we get
   //    grainType = T
   //    iterationSpace = [5, 4]
   var [iterationSpace, grainType, totalLength] =
     ComputeIterationSpace(arrayType, depth, len);
   // Create a zeroed instance with no data
   var result = arrayType.variable ? new arrayType(len) : new arrayType();
   var indices = NewDenseArray(depth);
   for (var i = 0; i < depth; i++) {
     indices[i] = 0;
   }
   var grainTypeIsComplex = !TypeDescrIsSimpleType(grainType);
   var size = DESCR_SIZE(grainType);
   var outOffset = 0;
   for (i = 0; i < totalLength; i++) {
     // Position out-pointer to point at &result[...indices], if appropriate.
     var userOutPointer = TypedObjectGetOpaqueIf(grainType, result, outOffset,
                                                 grainTypeIsComplex);
     // Invoke func(...indices, userOutPointer) and store the result
     callFunction(std_Array_push, indices, userOutPointer);
     var r = callFunction(std_Function_apply, func, undefined, indices);
     callFunction(std_Array_pop, indices);
     if (r !== undefined)
       TypedObjectSet(grainType, result, outOffset, r); // result[...indices] = r;
     // Increment indices.
     IncrementIterationSpace(indices, iterationSpace);
     outOffset += size;
   }
   return result;
 }
 function ComputeIterationSpace(arrayType, depth, len) {
   assert(IsObject(arrayType) && ObjectIsTypeDescr(arrayType), "ComputeIterationSpace called on non-type-object");
   assert(TypeDescrIsArrayType(arrayType), "ComputeIterationSpace called on non-array-type");
   assert(depth > 0, "ComputeIterationSpace called on non-positive depth");
   var iterationSpace = NewDenseArray(depth);
   iterationSpace[0] = len;
   var totalLength = len;
   var grainType = arrayType.elementType;
   for (var i = 1; i < depth; i++) {
     if (TypeDescrIsArrayType(grainType)) {
       var grainLen = grainType.length;
       iterationSpace[i] = grainLen;
       totalLength *= grainLen;
       grainType = grainType.elementType;
     } else {
       // RangeError("Depth "+depth+" too high");
       ThrowError(JSMSG_TYPEDOBJECT_ARRAYTYPE_BAD_ARGS);
     }
   }
   return [iterationSpace, grainType, totalLength];
 }
 function IncrementIterationSpace(indices, iterationSpace) {
   // Increment something like
   //     [5, 5, 7, 8]
   // in an iteration space of
   //     [9, 9, 9, 9]
   // to
   //     [5, 5, 8, 0]
   assert(indices.length === iterationSpace.length,
          "indices dimension must equal iterationSpace dimension.");
   var n = indices.length - 1;
   while (true) {
     indices[n] += 1;
     if (indices[n] < iterationSpace[n])
       return;
     assert(indices[n] === iterationSpace[n],
          "Components of indices must match those of iterationSpace.");
     indices[n] = 0;
     if (n == 0)
       return;
     n -= 1;
   }
 }
 // Implements |from| method for untyped |inArray|.  (Depth is implicitly 1 for untyped input.)
 function MapUntypedSeqImpl(inArray, outputType, maybeFunc) {
   assert(IsObject(outputType), "1. Map/From called on non-object outputType");
   assert(ObjectIsTypeDescr(outputType), "1. Map/From called on non-type-object outputType");
   inArray = ToObject(inArray);
   assert(TypeDescrIsArrayType(outputType), "Map/From called on non array-type outputType");
   if (!IsCallable(maybeFunc))
     ThrowError(JSMSG_NOT_FUNCTION, DecompileArg(0, maybeFunc));
   var func = maybeFunc;
   // Skip check for compatible iteration spaces; any normal JS array
   // is trivially compatible with any iteration space of depth 1.
   var outLength = outputType.variable ? inArray.length : outputType.length;
   var outGrainType = outputType.elementType;
   // Create a zeroed instance with no data
   var result = outputType.variable ? new outputType(inArray.length) : new outputType();
   var outUnitSize = DESCR_SIZE(outGrainType);
   var outGrainTypeIsComplex = !TypeDescrIsSimpleType(outGrainType);
   var outOffset = 0;
   // Core of map computation starts here (comparable to
   // DoMapTypedSeqDepth1 and DoMapTypedSeqDepthN below).
   for (var i = 0; i < outLength; i++) {
     // In this loop, since depth is 1, "indices" denotes singleton array [i].
     if (i in inArray) { // Check for holes (only needed for untyped case).
       // Extract element value.
       var element = inArray[i];
       // Create out pointer to point at &array[...indices] for result array.
       var out = TypedObjectGetOpaqueIf(outGrainType, result, outOffset,
                                        outGrainTypeIsComplex);
       // Invoke: var r = func(element, ...indices, collection, out);
       var r = func(element, i, inArray, out);
       if (r !== undefined)
         TypedObjectSet(outGrainType, result, outOffset, r); // result[i] = r
     }
     // Update offset and (implicitly) increment indices.
     outOffset += outUnitSize;
   }
   return result;
 }
 // Implements |map| and |from| methods for typed |inArray|.
 function MapTypedSeqImpl(inArray, depth, outputType, func) {
   assert(IsObject(outputType) && ObjectIsTypeDescr(outputType), "2. Map/From called on non-type-object outputType");
   assert(IsObject(inArray) && ObjectIsTypedObject(inArray), "Map/From called on non-object or untyped input array.");
   assert(TypeDescrIsArrayType(outputType), "Map/From called on non array-type outputType");
   if (depth <= 0 || TO_INT32(depth) !== depth)
     ThrowError(JSMSG_TYPEDOBJECT_BAD_ARGS);
   // Compute iteration space for input and output and check for compatibility.
   var inputType = TypeOfTypedObject(inArray);
   var [inIterationSpace, inGrainType, _] =
     ComputeIterationSpace(inputType, depth, inArray.length);
   if (!IsObject(inGrainType) || !ObjectIsTypeDescr(inGrainType))
     ThrowError(JSMSG_TYPEDOBJECT_BAD_ARGS);
   var [iterationSpace, outGrainType, totalLength] =
     ComputeIterationSpace(outputType, depth, outputType.variable ? inArray.length : outputType.length);
   for (var i = 0; i < depth; i++)
     if (inIterationSpace[i] !== iterationSpace[i])
       // TypeError("Incompatible iteration space in input and output type");
       ThrowError(JSMSG_TYPEDOBJECT_ARRAYTYPE_BAD_ARGS);
   // Create a zeroed instance with no data
   var result = outputType.variable ? new outputType(inArray.length) : new outputType();
   var inGrainTypeIsComplex = !TypeDescrIsSimpleType(inGrainType);
   var outGrainTypeIsComplex = !TypeDescrIsSimpleType(outGrainType);
   var inOffset = 0;
   var outOffset = 0;
   var isDepth1Simple = depth == 1 && !(inGrainTypeIsComplex || outGrainTypeIsComplex);
   var inUnitSize = isDepth1Simple ? 0 : DESCR_SIZE(inGrainType);
   var outUnitSize = isDepth1Simple ? 0 : DESCR_SIZE(outGrainType);
   // Bug 956914: add additional variants for depth = 2, 3, etc.
   function DoMapTypedSeqDepth1() {
     for (var i = 0; i < totalLength; i++) {
       // In this loop, since depth is 1, "indices" denotes singleton array [i].
       // Prepare input element/handle and out pointer
       var element = TypedObjectGet(inGrainType, inArray, inOffset);
       var out = TypedObjectGetOpaqueIf(outGrainType, result, outOffset,
                                        outGrainTypeIsComplex);
       // Invoke: var r = func(element, ...indices, collection, out);
       var r = func(element, i, inArray, out);
       if (r !== undefined)
         TypedObjectSet(outGrainType, result, outOffset, r); // result[i] = r
       // Update offsets and (implicitly) increment indices.
       inOffset += inUnitSize;
       outOffset += outUnitSize;
     }
     return result;
   }
   function DoMapTypedSeqDepth1Simple(inArray, totalLength, func, result) {
     for (var i = 0; i < totalLength; i++) {
       var r = func(inArray[i], i, inArray, undefined);
       if (r !== undefined)
         result[i] = r;
     }
     return result;
   }
   function DoMapTypedSeqDepthN() {
     var indices = new Uint32Array(depth);
     for (var i = 0; i < totalLength; i++) {
       // Prepare input element and out pointer
       var element = TypedObjectGet(inGrainType, inArray, inOffset);
       var out = TypedObjectGetOpaqueIf(outGrainType, result, outOffset,
                                        outGrainTypeIsComplex);
       // Invoke: var r = func(element, ...indices, collection, out);
       var args = [element];
       callFunction(std_Function_apply, std_Array_push, args, indices);
       callFunction(std_Array_push, args, inArray, out);
       var r = callFunction(std_Function_apply, func, void 0, args);
       if (r !== undefined)
         TypedObjectSet(outGrainType, result, outOffset, r); // result[...indices] = r
       // Update offsets and explicitly increment indices.
       inOffset += inUnitSize;
       outOffset += outUnitSize;
       IncrementIterationSpace(indices, iterationSpace);
     }
     return result;
   }
   if (isDepth1Simple)
     return DoMapTypedSeqDepth1Simple(inArray, totalLength, func, result);
   if (depth == 1)
     return DoMapTypedSeqDepth1();
   return DoMapTypedSeqDepthN();
 }
 // Implements |map| and |from| methods for typed |inArray|.
 function MapTypedParImpl(inArray, depth, outputType, func) {
   assert(IsObject(outputType) && ObjectIsTypeDescr(outputType),
          "Map/From called on non-type-object outputType");
   assert(IsObject(inArray) && ObjectIsTypedObject(inArray),
          "Map/From called on non-object or untyped input array.");
   assert(TypeDescrIsArrayType(outputType),
          "Map/From called on non array-type outputType");
   assert(typeof depth === "number",
          "Map/From called with non-numeric depth");
   assert(IsCallable(func),
          "Map/From called on something not callable");
   var inArrayType = TypeOfTypedObject(inArray);
   if (ShouldForceSequential() ||
       depth <= 0 ||
       TO_INT32(depth) !== depth ||
       !TypeDescrIsArrayType(inArrayType) ||
       !TypeDescrIsUnsizedArrayType(outputType))
   {
     // defer error cases to seq implementation:
     return MapTypedSeqImpl(inArray, depth, outputType, func);
   }
   switch (depth) {
   case 1:
     return MapTypedParImplDepth1(inArray, inArrayType, outputType, func);
   default:
     return MapTypedSeqImpl(inArray, depth, outputType, func);
   }
 }
 function RedirectPointer(typedObj, offset, outputIsScalar) {
   if (!outputIsScalar || !InParallelSection()) {
     // ^ Subtle note: always check InParallelSection() last, because
     // otherwise the other if conditions will not execute during
     // sequential mode and we will not gather enough type
     // information.
     // Here `typedObj` represents the input or output pointer we will
     // pass to the user function. Ideally, we will just update the
     // offset of `typedObj` in place so that it moves along the
     // input/output buffer without incurring any allocation costs. But
     // we can only do this if these changes are invisible to the user.
     //
     // Under normal uses, such changes *should* be invisible -- the
     // in/out pointers are only intended to be used during the
     // callback and then discarded, but of course in the general case
     // nothing prevents them from escaping.
     //
     // However, if we are in parallel mode, we know that the pointers
     // will not escape into global state. They could still escape by
     // being returned into the resulting array, but even that avenue
     // is impossible if the result array cannot contain objects.
     //
     // Therefore, we reuse a pointer if we are both in parallel mode
     // and we have a transparent output type.  It'd be nice to loosen
     // this condition later by using fancy ion optimizations that
     // assume the value won't escape and copy it if it does. But those
     // don't exist yet. Moreover, checking if the type is transparent
     // is an overapproximation: users can manually declare opaque
     // types that nonetheless only contain scalar data.
     typedObj = NewDerivedTypedObject(TYPEDOBJ_TYPE_DESCR(typedObj),
                                      typedObj, 0);
   }
   SetTypedObjectOffset(typedObj, offset);
   return typedObj;
 }
 SetScriptHints(RedirectPointer,         { inline: true });
 function MapTypedParImplDepth1(inArray, inArrayType, outArrayType, func) {
   assert(IsObject(inArrayType) && ObjectIsTypeDescr(inArrayType) &&
          TypeDescrIsArrayType(inArrayType),
          "DoMapTypedParDepth1: invalid inArrayType");
   assert(IsObject(outArrayType) && ObjectIsTypeDescr(outArrayType) &&
          TypeDescrIsArrayType(outArrayType),
          "DoMapTypedParDepth1: invalid outArrayType");
   assert(IsObject(inArray) && ObjectIsTypedObject(inArray),
          "DoMapTypedParDepth1: invalid inArray");
   // Determine the grain types of the input and output.
   const inGrainType = inArrayType.elementType;
   const outGrainType = outArrayType.elementType;
   const inGrainTypeSize = DESCR_SIZE(inGrainType);
   const outGrainTypeSize = DESCR_SIZE(outGrainType);
   const inGrainTypeIsComplex = !TypeDescrIsSimpleType(inGrainType);
   const outGrainTypeIsComplex = !TypeDescrIsSimpleType(outGrainType);
   const length = inArray.length;
   const mode = undefined;
   const outArray = new outArrayType(length);
   if (length === 0)
     return outArray;
   const outGrainTypeIsTransparent = ObjectIsTransparentTypedObject(outArray);
   // Construct the slices and initial pointers for each worker:
   const slicesInfo = ComputeSlicesInfo(length);
   const numWorkers = ForkJoinNumWorkers();
   assert(numWorkers > 0, "Should have at least the main thread");
   const pointers = [];
   for (var i = 0; i < numWorkers; i++) {
     const inTypedObject = TypedObjectGetDerivedIf(inGrainType, inArray, 0,
                                                   inGrainTypeIsComplex);
     const outTypedObject = TypedObjectGetOpaqueIf(outGrainType, outArray, 0,
                                                   outGrainTypeIsComplex);
     ARRAY_PUSH(pointers, ({ inTypedObject: inTypedObject,
                             outTypedObject: outTypedObject }));
   }
   // Below we will be adjusting offsets within the input to point at
   // successive entries; we'll need to know the offset of inArray
   // relative to its owner (which is often but not always 0).
   const inBaseOffset = TYPEDOBJ_BYTEOFFSET(inArray);
   ForkJoin(mapThread, 0, slicesInfo.count, ForkJoinMode(mode));
   return outArray;
   function mapThread(workerId, sliceStart, sliceEnd) {
     assert(TO_INT32(workerId) === workerId,
            "workerId not int: " + workerId);
     assert(workerId < pointers.length,
            "workerId too large: " + workerId + " >= " + pointers.length);
     var pointerIndex = InParallelSection() ? workerId : 0;
     assert(!!pointers[pointerIndex],
           "no pointer data for workerId: " + workerId);
     const { inTypedObject, outTypedObject } = pointers[pointerIndex];
     const sliceShift = slicesInfo.shift;
     var sliceId;
     while (GET_SLICE(sliceStart, sliceEnd, sliceId)) {
       const indexStart = SLICE_START_INDEX(sliceShift, sliceId);
       const indexEnd = SLICE_END_INDEX(sliceShift, indexStart, length);
       var inOffset = inBaseOffset + std_Math_imul(inGrainTypeSize, indexStart);
       var outOffset = std_Math_imul(outGrainTypeSize, indexStart);
       // Set the target region so that user is only permitted to write
       // within the range set aside for this slice. This prevents user
       // from writing to typed objects that escaped from prior slices
       // during sequential iteration. Note that, for any particular
       // iteration of the loop below, it's only valid to write to the
       // memory range corresponding to the index `i` -- however, since
       // the different iterations cannot communicate typed object
       // pointers to one another during parallel exec, we need only
       // fear escaped typed objects from *other* slices, so we can
       // just set the target region once.
       const endOffset = std_Math_imul(outGrainTypeSize, indexEnd);
       SetForkJoinTargetRegion(outArray, outOffset, endOffset);
       for (var i = indexStart; i < indexEnd; i++) {
         var inVal = (inGrainTypeIsComplex
                      ? RedirectPointer(inTypedObject, inOffset,
                                        outGrainTypeIsTransparent)
                      : inArray[i]);
         var outVal = (outGrainTypeIsComplex
                       ? RedirectPointer(outTypedObject, outOffset,
                                         outGrainTypeIsTransparent)
                       : undefined);
         const r = func(inVal, i, inArray, outVal);
         if (r !== undefined) {
           if (outGrainTypeIsComplex)
             SetTypedObjectValue(outGrainType, outArray, outOffset, r);
           else
             UnsafePutElements(outArray, i, r);
         }
         inOffset += inGrainTypeSize;
         outOffset += outGrainTypeSize;
         // A transparent result type cannot contain references, and
         // hence there is no way for a pointer to a thread-local object
         // to escape.
         if (outGrainTypeIsTransparent)
           ClearThreadLocalArenas();
       }
     }
     return sliceId;
   }
   return undefined;
 }
 SetScriptHints(MapTypedParImplDepth1,         { cloneAtCallsite: true });
 function ReduceTypedSeqImpl(array, outputType, func, initial) {
   assert(IsObject(array) && ObjectIsTypedObject(array), "Reduce called on non-object or untyped input array.");
   assert(IsObject(outputType) && ObjectIsTypeDescr(outputType), "Reduce called on non-type-object outputType");
   var start, value;
   if (initial === undefined && array.length < 1)
     // RangeError("reduce requires array of length > 0")
     ThrowError(JSMSG_TYPEDOBJECT_ARRAYTYPE_BAD_ARGS);
   // FIXME bug 950106 Should reduce method supply an outptr handle?
   // For now, reduce never supplies an outptr, regardless of outputType.
   if (TypeDescrIsSimpleType(outputType)) {
     if (initial === undefined) {
       start = 1;
       value = array[0];
     } else {
       start = 0;
       value = outputType(initial);
     }
     for (var i = start; i < array.length; i++)
       value = outputType(func(value, array[i]));
   } else {
     if (initial === undefined) {
       start = 1;
       value = new outputType(array[0]);
     } else {
       start = 0;
       value = initial;
     }
     for (var i = start; i < array.length; i++)
       value = func(value, array[i]);
   }
   return value;
 }
 function ScatterTypedSeqImpl(array, outputType, indices, defaultValue, conflictFunc) {
   assert(IsObject(array) && ObjectIsTypedObject(array), "Scatter called on non-object or untyped input array.");
   assert(IsObject(outputType) && ObjectIsTypeDescr(outputType), "Scatter called on non-type-object outputType");
   assert(TypeDescrIsSizedArrayType(outputType), "Scatter called on non-sized array type");
   assert(conflictFunc === undefined || typeof conflictFunc === "function", "Scatter called with invalid conflictFunc");
   var result = new outputType();
   var bitvec = new Uint8Array(result.length);
   var elemType = outputType.elementType;
   var i, j;
   if (defaultValue !== elemType(undefined)) {
     for (i = 0; i < result.length; i++) {
       result[i] = defaultValue;
     }
   }
   for (i = 0; i < indices.length; i++) {
     j = indices[i];
     if (!GET_BIT(bitvec, j)) {
       result[j] = array[i];
       SET_BIT(bitvec, j);
     } else if (conflictFunc === undefined) {
       ThrowError(JSMSG_PAR_ARRAY_SCATTER_CONFLICT);
     } else {
       result[j] = conflictFunc(result[j], elemType(array[i]));
     }
   }
   return result;
 }
 function FilterTypedSeqImpl(array, func) {
   assert(IsObject(array) && ObjectIsTypedObject(array), "Filter called on non-object or untyped input array.");
   assert(typeof func === "function", "Filter called with non-function predicate");
   var arrayType = TypeOfTypedObject(array);
   if (!TypeDescrIsArrayType(arrayType))
     ThrowError(JSMSG_TYPEDOBJECT_BAD_ARGS);
   var elementType = arrayType.elementType;
   var flags = new Uint8Array(NUM_BYTES(array.length));
   var count = 0;
   var size = DESCR_SIZE(elementType);
   var inOffset = 0;
   for (var i = 0; i < array.length; i++) {
     var v = TypedObjectGet(elementType, array, inOffset);
     if (func(v, i, array)) {
       SET_BIT(flags, i);
       count++;
     }
     inOffset += size;
   }
   var resultType = (arrayType.variable ? arrayType : arrayType.unsized);
   var result = new resultType(count);
   for (var i = 0, j = 0; i < array.length; i++) {
     if (GET_BIT(flags, i))
       result[j++] = array[i];
   }
   return result;
 }