* remove "cpu features" that are actually just processors
* rename `v8` to `v8a`. this matches the corresponding
change to target/aarch64.zig
* rename types in preparation for removing sub-architecture
from `std.Target`.
I have other files changed in my dirty working tree, but about to make
some changes to arm.zig that I don't want batched with this commit.
The commit 70ee818d21c44ec0031b997916694327eb9fc37f
(update target CPUs and features with llvm10's data)
accidentally reverted 6793af8d8b370cefc0a1fccbcf1c9fd1a24c7378.
This un-reverts it.
Previously it was a tagged union which was one of:
* baseline
* a specific CPU
* a set of features
Now, it's possible to have a CPU but also modify the CPU's feature set
on top of that. This is closer to what LLVM does.
This is more correct because Zig's notion of CPUs (and LLVM's) is not
exact CPU models. For example "skylake" is not one very specific model;
there are several different pieces of hardware that match "skylake" that
have different feature sets enabled.
This reverts commit 6dd514ac8aa3ee2e5c6fd0374469d361ccfce5b9.
This strategy won't work for arm 32-bit; instead need to try to figure
out how to get more bits into the bit set.
