Notable changes:
`_i386`, `_i486`, and `_i686` are renamed to `i386`, `i486`,
and `i686` respectively. `std.zig.fmtId` is enhanced to support
formatting `i386` as `@"i386"`.
Some CPU features which are actually CPU models have been
properly flattened, such as `apple_a12`, `apple_a13`, `apple_a7`,
`cortex_a78c`, `exynos_m4`, `neoverse_e1`, `neoverse_n1`,
`neoverse_n2`, `neoverse_v1`.
Some CPU features have been added and some have been removed, following
LLVM's lead.
CSky CPU features support is added.
The idea is to depend on this language feature as little as possible
with the hopes that it can be adjusted to be less of an anti-pattern.
This also helps self-hosted, which does not yet implement
`usingnamespace`, get closer to being able to build compiler-rt.
The tools/update_cpu_features script is coming along, and generates
correct information for all these targets. The remaining targets are:
* arm
* aarch64
* amdgpu
* riscv
I will commit them once the issues with the updater tool are resolved.
in favor of CPU features. Also rearrange the `std.Target`
data structure.
* note: `@import("builtin")` was already deprecated in favor of
`@import("std").builtin`.
* `std.builtin.arch` is now deprecated in favor of
`std.builtin.cpu.arch`.
* `std.Target.CpuFeatures.Cpu` is now `std.Target.Cpu.Model`.
* `std.Target.CpuFeatures` is now `std.Target.Cpu`.
* `std.Target` no longer has an `arch` field. Instead it has a
`cpu` field, which has `arch`, `model`, and `features`.
* `std.Target` no longer has a `cpu_features` field.
* `std.Target.Arch` is moved to `std.Target.Cpu.Arch` and
it is an enum instead of a tagged union.
* `std.Target.parseOs` is moved to `std.Target.Os.parse`.
* `std.Target.parseAbi` is moved to `std.Target.Abi.parse`.
* `std.Target.parseArchSub` is only for arch now and moved
to `std.Target.Cpu.Arch.parse`.
* `std.Target.parse` is improved to accept CPU name and features.
* `std.Target.Arch.getBaselineCpuFeatures` is moved to
`std.Target.Cpu.baseline`.
* `std.Target.allCpus` is renamed to `std.Target.allCpuModels`.
* `std.Target.defaultAbi` is moved to `std.Target.Abi.default`.
* Significant cleanup of aarch64 and arm CPU features, resulting in
the needed bit count for cpu feature set going from 174 to 138.
* Add `std.Target.Cpu.Feature.Set.addFeatureSet` for merging
feature sets together.
`-target-feature` and `-target-cpu` are removed in favor of
`-mcpu`, to conform to established conventions, and it gains
additional power to support cpu features. The syntax is:
-mcpu=name+on1+on2-off1-off2
closes#4261
