trunc_f64_u: Wasm text instruction
The trunc_f64_u instruction removes the fractional part of an f64 value and outputs it as an unsigned integer.
This is a separate instruction, trunc, which removes the fractional part of a float and outputs a float.
There are also other truncate integer conversion instructions:
Try it
(module
(import "console" "log" (func $log (param i32)))
(func $main
f64.const 2300044.4 ;; load a number onto the stack
i32.trunc_f64_u ;; discard decimal part and return unsigned integer
call $log ;; log the result
)
(start $main)
)
const url = "{%wasm-url%}";
await WebAssembly.instantiateStreaming(fetch(url), { console });
Syntax
value_type.trunc_f64_u
value_type-
The type of value the instruction is being run on. The following types support
trunc_f64_u:i32i64
trunc_f64_u-
The
trunc_f64_uinstruction. Must always be included after thevalue_typeand a period (.).
Type
[input] -> [output]
Binary encoding
| Instruction | Binary format | Example text => binary |
|---|---|---|
i32.trunc_f64_u |
0xab |
i32.trunc_f64_u => 0xab |
i64.trunc_f64_u |
0xb1 |
i64.trunc_f64_u => 0xb1 |