trunc_sat_f32x4_u: Wasm SIMD conversion instruction

The trunc_sat_f32x4_u SIMD conversion instruction performs a saturating conversion of the lanes of a v128 f32x4 value interpretation into an unsigned i32x4 value interpretation, clamping the output to the range allowed by the value type.

Try it

(module
  (import "console" "log" (func $log (param i32)))
  (func $main
    v128.const f32x4 1300.5 60.4 0.5 780000.4

    i32x4.trunc_sat_f32x4_u
    i32x4.extract_lane 3
    call $log ;; log the result
  )
  (start $main)
)
WebAssembly.instantiateStreaming(fetch("{%wasm-url%}"), { console });

Saturation means that the output values are clamped to the upper and lower values allowed by the value interpretation. Allowed output values are 0 to 4,294,967,295 (the full range of an unsigned 32-bit integer). NaN values are converted to 0.

Syntax

value_type.trunc_sat_f32x4_u
value_type

The type of value the instruction is being run on. The following v128 value interpretations support trunc_sat_f32x4_u:

  • i32x4
trunc_sat_f32x4_u

The trunc_sat_f32x4_u instruction. Must always be included after the value_type and a period (.).

Type

[input] -> [output]
input

The input v128 f32x4 value interpretation.

output

The output v128 i32x4 value interpretation.

Binary encoding

Instruction Binary format Example text => binary
i32x4.trunc_sat_f32x4_u 0xfd 249:u32 i32x4.trunc_sat_f32x4_u => 0xfd 0xf9 0x01

Specifications

This feature does not appear to be defined in any specification.

Browser compatibility

See also