max_s: Wasm SIMD arithmetic instruction

The max_s instruction compares two v128 signed integer value interpretations and returns a new interpretation with each lane set to the greater of that lane index's value on the two inputs.

Try it

(module
  (import "console" "log" (func $log (param i32)))
  (func $main
    ;; load two v128 i16x8s onto the stack
    v128.const i16x8 10 400 0 86 87 9000 -5 19
    v128.const i16x8 200 20 0 -5 80 9 -6 283

    ;; return a i16x8 containing the greatest values from each input
    i16x8.max_s
    i16x8.extract_lane_s 5 ;; Extract a single lane
    call $log ;; log the result
  )
  (start $main)
)
const url = "{%wasm-url%}";
await WebAssembly.instantiateStreaming(fetch(url), { console });

Syntax

value_type.max_s
value_type

The type of value the instruction is being run on. The following types support max_s:

max_s

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

Type

[input1, input2] -> [output]
input1

The first input value.

input2

The second input value.

output

The output value. A new v128 of the same type as the inputs, with each lane set to the greater of that lane index's value on the two inputs.

Binary encoding

InstructionBinary formatExample text => binary
i8x16.max_s0xfd 120:u32i8x16.max_s => 0xfd 0x78
i16x8.max_s0xfd 152:u32i16x8.max_s => 0xfd 0x98 0x01
i32x4.max_s0xfd 184:u32i32x4.max_s => 0xfd 0xb8 0x01

Specifications

See also