This is an experimental technology, part of the Harmony (ECMAScript 7) proposal.
Because this technology's specification has not stabilized, check the compatibility table for usage in various browsers. Also note that the syntax and behavior of an experimental technology is subject to change in future version of browsers as the spec changes.
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- An double specifying the value of the first lane. Defaults to
NaN
. y
Optional- An double specifying the value of the second lane. Defaults to
NaN
.
Constructors
In addition to the simple constructors, the SIMD API provides the following constructor. Note that you can also convert from another SIMD data type to float64x2.
SIMD.float64x2.splat()
- Creates a float64x2 with all lanes set to a given value.
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()
- Returns a new float64x2 with the lane values loaded from a typed array.
SIMD.float64x2.store()
- 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 float64x2 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/max and clamping
SIMD.float64x2.clamp()
- Returns a new float64x2 with the lane values clamped between a lower limit and an upper limit.
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 float64x2 with the lane values being a mix of the lanes depending on the selector mask.
SIMD.float64x2.selectBits()
- Returns a new float64x2 with the lane values being a mix of bits 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 (packing / unpacking)
SIMD.float64x2.fromInt32x4()
- Creates a new float64x2 data type with a float conversion from an int32x4.
SIMD.float64x2.fromInt32x4Bits()
- Creates a new float64x2 data type with a bit-wise copy from an int32x4.
SIMD.float64x2.fromFloat32x4()
- Creates a new float64x2 data type with a float conversion from a float32x4.
SIMD.float64x2.fromFloat32x4Bits()
- Creates a new float64x2 data type with a bit-wise copy from a float32x4.
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.
Examples
Constructing an float64x2
new SIMD.float64x2(1, 2); // float64x2[1, 2] new SIMD.float64x2(1); // float64x2[1, NaN] new SIMD.float64x2(); // float64x2[NaN, NaN]
Specifications
SIMD is not yet part of an official standards document or draft. For standardization work and a Polyfill implementation based on typed arrays, see the ecmascript_simd GitHub repository.
Browser compatibility
Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari |
---|---|---|---|---|---|
Basic support | Not supported | Nightly build | Not supported | Not supported | Not supported |
Feature | Android | Chrome for Android | Firefox Mobile (Gecko) | IE Mobile | Opera Mobile | Safari Mobile |
---|---|---|---|---|---|---|
Basic support | Not supported | Not supported | Nightly build | Not supported | Not supported | Not supported |