Thanks Aram and Michael, that helps a lot. I've studied https://github.com/golang/go/tree/master/src/crypto/sha1 which looks like a good example of having a pure-go fallback with architecture-specific assembly.
My next question is which tool is responsible for selecting the correct sha1block_GOARCH.s? Is the the compiler, linker, or where? On Tuesday, September 13, 2016 at 9:32:25 AM UTC-6, Aram Hăvărneanu wrote: > > On Tue, Sep 13, 2016 at 6:19 AM, <pcj...@gmail.com <javascript:>> wrote: > > My interpretation of golang's assembly is that it represents an > intermediate > > pseudo-language that is transformed via "instruction selection" to a > > concrete form. > > Correct, but this pseudo-language is not portable between architectures. > > > Therefore, is it possible to re-write the above to a cross-compilable > form? > > The assembly in the Go distribution is already cross-compilable, but > looking at your example you are not concerned whether the assembly is > cross-compilable or not (that depends on the toolchain, and not on the > assembly code), but you want the assembly to be portable between > architectures. > > Apart from the most trivial of cases, this is not possible. Different > targets use different instructions and different registers. > > The Go assembler uses the same *syntax* on every architecture, so it > can be parsed and processed by a single program, however the assembly > code required for each target is very different. > > -- > Aram Hăvărneanu > -- 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. For more options, visit https://groups.google.com/d/optout.
