The extract_lane_u SIMD extract instruction extracts the value contained within the specified lane of a v128 value interpretation as an unsigned integer.

(module
  (import "console" "log" (func $log (param i32)))
  (func $main
    ;; load a SIMD value onto the stack
    (v128.const i16x8 1 0 -2 -1 -4 -2 -2 3)

    i16x8.extract_lane_u 6 ;; Extract a scalar value from the result
    call $log ;; log the result
  )
  (start $main)
)

WebAssembly.instantiateStreaming(fetch("{%wasm-url%}"), { console });

Syntax

value_type.extract_lane_u

• value_type

  • : The type of value the instruction is being run on. The following v128 value interpretations support extract_lane_u:

    • i8x16

    • i16x8

  extract_lane_u

  • : The extract_lane_u instruction. Must always be included after the value_type and a period (.).

Type

[input, lane] -> [output]

• input

  • : The v128 value interpretation you want to extract a lane from.

  lane

  • : The index of the lane whose value you wish to extract, for example 0.

  output

  • : The value extracted from the lane.

Binary encoding

InstructionBinary formatExample text => binaryi8x16.extract_lane_u0xfd 22:u32 l:lane_idxi8x16.extract_lane_u 11 => 0xfd 0x16 0x0bi16x8.extract_lane_u0xfd 25:u32 l:lane_idxi16x8.extract_lane_u 7 => 0xfd 0x19 0x07

Specifications

Browser compatibility

See also

• extract_lane