The narrow_i32x4_u SIMD conversion instruction converts two signed v128 i32x4 value interpretations into an i16x8 value interpretation using unsigned saturation (clamping to the range between 0 to 65,535).

(module
  (import "console" "log" (func $log (param i32)))
  (func $main
    v128.const i32x4 200 210 220 230
    v128.const i32x4 300 310 320 330

    i16x8.narrow_i32x4_u
    i16x8.extract_lane_s 7
    call $log ;; log the result
  )
  (start $main)
)

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

Syntax

i16x8.narrow_i32x4_u

• i16x8.narrow_i32x4_u

  • : The i16x8.narrow_i32x4_u instruction.

Type

[input1, input2] -> [output]

• input1

  • : The first input v128 i32x4 value interpretation.

  input2

  • : The second input v128 i32x4 value interpretation.

  output

  • : The output v128 i16x8 value interpretation.

Binary encoding

InstructionBinary formatExample text => binaryi16x8.narrow_i32x4_u0xfd 134:u32i16x8.narrow_i32x4_u => 0xfd 0x86 0x01

Specifications

Browser compatibility