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Note: The Float64x2 type is currently not part of the SIMD specification draft.
The SIMD.Float64x2
data type is a 128-bit vector divided into 2 lanes storing double precision floating point values.
Figure 1: SIMD.Float64x2 in a 128-bit SIMD register.
Syntax
SIMD.Float64x2(x, y);
Parameters
x
Optional- A double specifying the value of the first lane. Defaults to
NaN
. y
Optional- A double specifying the value of the second lane. Defaults to
NaN
.
Constructor functions
In addition to the simple creator functions, the SIMD API provides the following constructor functions:
SIMD.Float64x2.splat()
- Creates a Float64x2 with all lanes set to a given value.
Note that you can also convert from another SIMD data type to Float64x2.
Note: SIMD types don't work with new
, as SIMD values are no "boxed" objects (comparable to String(s)
vs. new String(s)
, which creates a String object).
var v = new SIMD.Float64x2(1,2); // TypeError: SIMD.Float64x2 is not a constructor var w = new SIMD.Float64x2.splat(3); // TypeError: SIMD.Float64x2.splat is not a constructor
Instead, you just write:
var v = SIMD.Float64x2(1,2); var w = SIMD.Float64x2.splat(3);
Operations
To actually do something with SIMD types, SIMD operations are needed that work on SIMD data types.
Checking SIMD types
SIMD.Float64x2.check()
- Returns a new Float64x2 if the parameter is a valid Float64x2 data type. Throws a
TypeError
otherwise.
Accessing and mutating lanes
SIMD.Float64x2.extractLane()
- Returns the value of the given lane.
SIMD.Float64x2.replaceLane()
- Returns a new Float64x2 with the given lane value replaced.
Loading from and storing into typed arrays
SIMD.Float64x2.load()
SIMD.Float64x2.load1()
- Returns a new Float64x2 with the lane values loaded from a typed array.
SIMD.Float64x2.store()
SIMD.Float64x2.store1()
- Stores a Float64x2 into a typed array.
Arithmetic operations
SIMD.Float64x2.abs()
- Returns a new Float64x2 with the absolute lane values.
SIMD.Float64x2.add()
- Returns a new Float64x2 with the lane values added (
a + b
). SIMD.Float64x2.div()
- Returns a new Float64x2 with the lane values divided (
a / b
). SIMD.Float64x2.mul()
- Returns a new loat64x2 with the lane values multiplied (
a * b
). SIMD.Float64x2.neg()
- Returns a new Float64x2 with the negated lane values.
SIMD.Float64x2.reciprocalApproximation()
- Returns a new Float64x2 with an approximation of the reciprocal lane values.
SIMD.Float64x2.reciprocalSqrtApproximation()
- Returns a new Float64x2 with an approximation of the reciprocal square root lane values.
SIMD.Float64x2.sub()
- Returns a new Float64x2 with the lane values subtracted (
a - b
). SIMD.Float64x2.sqrt()
- Returns a new Float64x2 with the square root of the lane values.
Shuffling and swizzling
SIMD.Float64x2.shuffle()
- Returns a new Float64x2 with the lane values shuffled.
SIMD.Float64x2.swizzle()
- Returns a new Float64x2 with the lane values swizzled.
Min and max values
SIMD.Float64x2.max()
- Returns a new Float64x2 with the maximum of the lane values.
SIMD.Float64x2.maxNum()
- Returns a new Float64x2 with the maximum of the lane values, preferring numbers over
NaN
. SIMD.Float64x2.min()
- Returns a new Float64x2 with the minimum of the lane values.
SIMD.Float64x2.minNum()
- Returns a new Float64x2 with the minimum of the lane values, preferring numbers over
NaN
.
Selections
SIMD.Float64x2.select()
- Returns a new loat64x2 with the lane values being a mix of the lanes depending on the selector mask.
Comparisons
SIMD.Float64x2.equal()
- Returns a selection mask depending on
a == b
. SIMD.Float64x2.notEqual()
- Returns a selection mask depending on
a != b
. SIMD.Float64x2.lessThan()
- Returns a selection mask depending on
a < b
. SIMD.Float64x2.lessThanOrEqual()
- Returns a selection mask depending on
a <= b
. SIMD.Float64x2.greaterThan()
- Returns a selection mask depending on
a > b
. SIMD.Float64x2.greaterThanOrEqual()
- Returns a selection mask depending on
a >= b
.
Data conversions
SIMD.Float64x2.fromFloat32x4Bits()
- Creates a new Float64x2 data type with a bit-wise copy from a Float32x4.
SIMD.Float64x2.fromInt32x4Bits()
- Creates a new Float64x2 data type with a bit-wise copy from an Int32x4.
SIMD.Float64x2.fromInt16x8Bits()
- Creates a new Float64x2 data type with a bit-wise copy from an Int16x8.
SIMD.Float64x2.fromInt8x16Bits()
- Creates a new Float64x2 data type with a bit-wise copy from an Int8x16.
SIMD.Float64x2.fromUint32x4Bits()
- Creates a new Float64x2 data type with a bit-wise copy from a Uint32x4.
SIMD.Float64x2.fromUint16x8Bits()
- Creates a new Float64x2 data type with a bit-wise copy from a Uint16x8.
SIMD.Float64x2.fromUint8x16Bits()
- Creates a new Float64x2 data type with a bit-wise copy from a Uint8x16.
SIMD prototype
The following methods and properties are installed on the SIMD.Float64x2.prototype
.
SIMD.Float64x2.prototype.constructor
- Specifies the function that creates a SIMD object's prototype.
SIMD.Float64x2.prototype.toLocaleString()
- Returns a localized string representing the SIMD type and its elements. Overrides the
Object.prototype.toLocaleString()
method. SIMD.Float64x2.prototype.toString()
- Returns a string representing the SIMD type and its elements. Overrides the
Object.prototype.toString()
method. SIMD.Float64x2.prototype.valueOf()
- Returns the primitive value of a SIMD object.
SIMD.Float64x2.prototype.toSource()
- Returns a string representing the source code of the object. Overrides the
Object.prototype.toSource()
method.
Examples
Constructing a Float64x2
SIMD.Float64x2(1, 2); // Float64x2[1, 2] SIMD.Float64x2(1); // Float64x2[1, NaN] SIMD.Float64x2(); // Float64x2[NaN, NaN]
Specifications
The Float64x2 type is currently not part of the SIMD specification draft.
Browser compatibility
Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari |
---|---|---|---|---|---|
Basic support | No support | Nightly build | No support | No support | No support |
Feature | Android | Chrome for Android | Firefox Mobile (Gecko) | IE Mobile | Opera Mobile | Safari Mobile |
---|---|---|---|---|---|---|
Basic support | No support | No support | Nightly build | No support | No support | No support |