q/src/x64/SIB.go

20 lines
499 B
Go

package x64
// ScaleFactor encodes the scale factor.
type ScaleFactor = byte
const (
Scale1 = ScaleFactor(0b00)
Scale2 = ScaleFactor(0b01)
Scale4 = ScaleFactor(0b10)
Scale8 = ScaleFactor(0b11)
)
// SIB is used to generate an SIB byte.
// - scale: 2 bits. Multiplies the value of the index.
// - index: 3 bits. Specifies the index register.
// - base: 3 bits. Specifies the base register.
func SIB(scale ScaleFactor, index byte, base byte) byte {
return (scale << 6) | (index << 3) | base
}