As far as I am aware: A LEA with a scale of 3 does not exist on amd64. Scale can be 1,2,4,8.
A LEA with 3 arguments LEAQ 4(AX)(AX*2) on many modern amd64 compatible machines will use 3 cycles instead of 2 for two simpler LEA. The newest generation of Intel CPUs seems to have gotten better again avoiding slow LEA. https://github.com/golang/go/issues/21735 https://github.com/golang/go/issues/31900 On Wednesday, August 26, 2020 at 5:04:15 AM UTC+2, xie cui wrote: > > function: > func test3(a int) int { > return a * 3 + 4 > } > > go version go1.13.5 darwin/amd64 > generate instructions: > LEAQ (AX)(AX*2), AX > LEAQ 4(AX), AX > > As far as i known，there a better choice > LEAQ 4(AX*3), AX > > Can it be optimized? > > -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. To unsubscribe from this group and stop receiving emails from it, send an email to golang-nuts+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/golang-nuts/0d638194-eaf0-4b99-b66e-c831d8491470o%40googlegroups.com.
