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SIMD.js has been taken out of active development in TC39 and removed from Stage 3. It is not being pursued by web browsers for implementation anymore. SIMD operations exposed to the web are under active development within WebAssembly, with operations based on the SIMD.js operations.

The SIMD.Int8x16 data type is a 128-bit vector divided into 16 lanes storing 8-bit signed integer values.

SIMD.Int8x16

Figure 1: SIMD.Int8x16 in a 128-bit SIMD register.

Syntax

SIMD.Int8x16(s0,s1,s2,s3,s4,s5,s6,s7,s8,s9,s10,s11,s12,s13,s14,s15);

Parameters

s[0-15] Optional
An integer specifying the value of the lane. Defaults to 0.

Constructor functions

In addition to the simple creator functions, the SIMD API provides the following constructor functions:

SIMD.Int8x16.splat()
Creates an Int8x16 with all lanes set to a given value.

Note that you can also convert from another SIMD data type to Int8x16.

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.Int8x16(1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16); 
// TypeError: SIMD.Int8x16 is not a constructor
var w = new SIMD.Int8x16.splat(3); 
// TypeError: SIMD.Int8x16.splat is not a constructor

Instead, you just write:

var v = SIMD.Int8x16(1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16);
var w = SIMD.Int8x16.splat(3); 

Operations

To actually do something with SIMD types, SIMD operations are needed that work on SIMD data types.

Checking SIMD types

SIMD.Int8x16.check()
Returns a new Int8x16 if the parameter is a valid Int8x16 data type. Throws a TypeError otherwise.

Accessing and mutating lanes

SIMD.Int8x16.extractLane()
Returns the value of the given lane.
SIMD.Int8x16.replaceLane()
Returns a new Int8x16 with the given lane value replaced.

Loading from and storing into typed arrays

SIMD.Int8x16.load()
Returns a new Int8x16 with the lane values loaded from a typed array.
SIMD.Int8x16.store()
Stores an Int8x16 into a typed array.

Arithmetic operations

SIMD.Int8x16.add()
Returns a new Int8x16 with the lane values added (a + b).
SIMD.Int8x16.addSaturate()
Returns a new Int8x16 with the lane values added (a + b) and saturating behavior on overflow.
SIMD.Int8x16.mul()
Returns a new Int8x16 with the lane values multiplied (a * b).
SIMD.Int8x16.neg()
Returns a new Int8x16 with the negated lane values.
SIMD.Int8x16.sub()
Returns a new Int8x16 with the lane values subtracted (a - b).
SIMD.Int8x16.subSaturate()
Returns a Int8x16 instance with the lane values subtracted (a - b) and saturating behavior on overflow.

Shuffling and swizzling

SIMD.Int8x16.shuffle()
Returns a new Int8x16 with the lane values shuffled.
SIMD.Int8x16.swizzle()
Returns a new Int8x16 with the lane values swizzled.

Selections

SIMD.Int8x16.select()
Returns a new Int8x16 with the lane values being a mix of the lanes depending on the selector mask.

Comparisons

SIMD.Int8x16.equal()
Returns a selection mask depending on a == b.
SIMD.Int8x16.notEqual()
Returns a selection mask depending on a != b.
SIMD.Int8x16.lessThan()
Returns a selection mask depending on a < b.
SIMD.Int8x16.lessThanOrEqual()
Returns a selection mask depending on a <= b.
SIMD.Int8x16.greaterThan()
Returns a selection mask depending on a > b.
SIMD.Int8x16.greaterThanOrEqual()
Returns a selection mask depending on a >= b.

Bitwise logical operations

SIMD.Int8x16.and()
Returns a new Int8x16 with the logical AND of the lane values (a & b).
SIMD.Int8x16.or()
Returns a new Int8x16 with the logical OR of the lane values (a | b).
SIMD.Int8x16.xor()
Returns a new Int8x16 with the logical XOR of the lane values (a ^ b).
SIMD.Int8x16.not()
Returns a new Int8x16 with lane with the logical NOT of the lane values (~a).

Bitwise shift operations

SIMD.Int8x16.shiftLeftByScalar()
Returns a new Int8x16 with the lane values shifted left by a given bit count (a << bits).
SIMD.Int8x16.shiftRightByScalar()
Returns a new Int8x16 with the lane values shifted right.

Data conversions

SIMD.Int8x16.fromFloat32x4Bits()
Creates a new Int8x16 data type with a bit-wise copy from a Float32x4.
SIMD.Int8x16.fromFloat64x2Bits()
Creates a new Int8x16 data type with a bit-wise copy from a Float64x2.
SIMD.Int8x16.fromInt32x4Bits()
Creates a new Int8x16 data type with a bit-wise copy from an Int32x4.
SIMD.Int8x16.fromInt16x8Bits()
Creates a new Int8x16 data type with a bit-wise copy from an Int16x8.
SIMD.Int8x16.fromUint32x4Bits()
Creates a new Int8x16 data type with a bit-wise copy from a Uint32x4.
SIMD.Int8x16.fromUint16x8Bits()
Creates a new Int8x16 data type with a bit-wise copy from a Uint16x8.
SIMD.Int8x16.fromUint8x16Bits()
Creates a new Int8x16 data type with a bit-wise copy from an Uint8x16.

SIMD prototype

The following methods and properties are installed on the SIMD.Int8x16.prototype.

SIMD.Int8x16.prototype.constructor
Specifies the function that creates a SIMD object's prototype.
SIMD.Int8x16.prototype.toLocaleString()
Returns a localized string representing the SIMD type and its elements. Overrides the Object.prototype.toLocaleString() method.
SIMD.Int8x16.prototype.toString()
Returns a string representing the SIMD type and its elements. Overrides the Object.prototype.toString() method.
SIMD.Int8x16.prototype.valueOf()
Returns the primitive value of a SIMD object.
SIMD.Int8x16.prototype.toSource()
Returns a string representing the source code of the object. Overrides the Object.prototype.toSource() method.

Examples

Constructing an Int8x16

SIMD.Int8x16(1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16);
 // Int8x16[1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16]
SIMD.Int8x16(1, 2);
 // Int8x16[1, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0]
SIMD.Int8x16();
 // Int8x16[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0]

Specifications

Specification Status Comment
SIMD
The definition of 'Int8x16' in that specification.
Draft Initial definition.

Browser compatibility

Feature Chrome Edge Firefox (Gecko) Internet Explorer Opera Safari
Basic support No support Nightly build Nightly build No support No support No support
Feature Android Chrome for Android Edge Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support No support No support Nightly build Nightly build No support No support No support

See also

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