Some vector registers must be preserved across calls, but this wasn't
happening on Linux and MacOS. When I added support for windows/arm64, I
saw that it required these vector registers to be preserved and assumed
this was Windows deviating from the standard calling convention. But
actually, Windows was just implementing the standard calling convention
and the bug was on Linux and MacOS.
This commit fixes the bug on Linux and MacOS and at the same time merges
the Go and assembly files as they no longer need to be separate.
This patch adds support for generating GOOS=darwin GOARCH=arm64
binaries. This means that it will become possible to run `go test` on
recent Macs, for example.
This results in smaller and likely more efficient code. It does require
some architecture specific code for each architecture, but I've kept the
amount of code as small as possible.
Ayke van Laethem