Truncate (float to int)

The trunc instructions, are used for converting floating points to integers. It's named truncate since it truncates the fractional part of the number when doing the conversion. There are signed and unsigned versions of this instruction.

There's another trunc instruction that truncates the fractional part of a floating point without converting it to and integer.

Try it


;; push an f32 onto the stack
f32.const 10.5

;; convert from f32 to signed i32 rounding towards zero (.5 will be lost)

;; the top item on the stack will now be the value 10 of type f32
Instruction Binary opcode
i32.trunc_f32_s 0xa8
i32.trunc_f32_u 0xa9
i32.trunc_f64_s 0xaa
i32.trunc_f64_u 0xab
i64.trunc_f32_s 0xae
i64.trunc_f32_u 0xaf
i64.trunc_f64_s 0xb0
i64.trunc_f64_u 0xb1