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This is an experimental technology
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 versions of browsers as the specification changes.
The SIMD.Int8x16
data type is a 128-bit vector divided into 16 lanes storing 8-bit signed integer values.
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 | 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 |