return: Wasm text instruction

return returns from a function.

If there are no values left on the stack, it returns nothing/void.
If there are the same amount of values left on the stack as specified in the function's type signature, it returns those values.
If there are more values than the function's return type specifies, then the topmost N values are returned, and the remaining values on the stack are discarded.

Try it

(module
  (func (export "get_90") (result i32)
    ;; load 10 onto the stack
    i32.const 10
    ;; load 90 onto the stack
    i32.const 90
    ;; return the second value (90); the first is discarded
    return
  )
)

const url = "{%wasm-url%}";
await WebAssembly.instantiateStreaming(fetch(url)).then((result) => {
  const { get_90 } = result.instance.exports;
  console.log(get_90());
  // Expected output: 90
});

Syntax

wat

f32.const 4.3
return

wat

i32.const 7
f32.const 4.3
return

Instruction	Binary opcode
`return`	`0x0f`

Specifications

WebAssembly Core Specification