Fix icelake marches

[danog]

The icelake march actually doesn't exist, only the icelake-server and icelake-client variants exist.

[ptr1337]

Good catch, would you mind also to upstream the patch to the official architecutre repository from graysky?

[ptr1337]

https://github.com/graysky2/kernel_compiler_patch

[danog]

@ptr1337 Sure, but actually, I don't really like the current approach of arch selection at all: I consider this to be a hotfix, because there is a large number of arches supported by both rustc and gcc/clang that isn't listed here; the best solution should just be something autogenerated, but there are some subarch-dependent config flags that are a bit cryptic and I can't quite tell how they could be autogenerated.

For example, I was thinking of completely dropping all MARCH variants (except for a few like the amd ones that require -mno-tbm), and specifying a string config flag that allows passing in raw rust/C compilation flags (which would be really neat to work with in combination with https://github.com/hartwork/resolve-march-native, and would allow further optimization like l1/2-cache-size flags & so on).

However, this may not work well with configs like X86_L1_CACHE_SHIFT, X86_INTEL_USERCOPY, X86_USE_PPRO_CHECKSUM, unless there's a simple way to extract the correct value for those config flags from the compilation flags generated by resolve-march-native (also the rustflags can be a bit problematic, but for the time being I think we could just copy just the -march from the custom cflags without any other option, they mostly coincide)...

(also ping @graysky2)

[danog]

I made this PR since I personally need optimized builds specifically for icelake-server, zen2/3/4 and alderlake, but a more universal solution would be much better I think...

[sirlucjan]

Please fix this patch error:

patch: **** malformed patch at line 514: + help

[danog]

This should do it

[sirlucjan]

Yes, thanks.

[1Naim]

CachyOS/linux@a1cc72e Queued for the next sync. Expect to see this in the repository some time next week. Thank you.