compiler: factor Windows x86-32 ABI impl into its own file
While it shares more than zero code with the SysV x86-32 ABI impl, there is no particular reason to organize wildly different ABIs using if-else in the same function.
While it shares more than zero code with the SysV x86-32 ABI impl,
there is no particular reason to organize wildly different ABIs
using if-else in the same function.
Workaround Cranelift not yet properly supporting vectors smaller than 128bit
While it would technically be possible to workaround this in cg_clif, it quickly becomes very messy and would likely cause correctness issues. Working around it in rustc instead is much simper and won't have any negative impact for code running on stable as vectors smaller than 128bit can only be made on nightly using core::simd or #[repr(simd)].
While it would technically be possible to workaround this in cg_clif, it
quickly becomes very messy and would likely cause correctness issues.
Working around it in rustc instead is much simper and won't have any
negative impact for code running on stable as vectors smaller than
128bit can only be made on nightly using core::simd or #[repr(simd)].
We cannot produce anything useful if asked to compile unknown targets.
We should handle the error immediately at the point of discovery instead
of propagating it upward, and preferably in the simplest way: Die.
This allows cleaning up our "error-handling" spread across 5 crates.
It is speculated that these two can be conceptually merged, and it can
start by ripping out rustc's notion of the PtxKernel call convention.
Leave the ExternAbi for now, but the nvptx target now should see it as
just a different way to spell Conv::GpuKernel.
rustc_target has had a lot of weird reexports for various reasons, but
now we're at a point where we can actually start reducing their number.
We remove weird shadowing-dependent behavior and import directly from
rustc_abi instead of doing weird renaming imports.
This is only incremental progress and does not entirely fix the crate.
Add gpu-kernel calling convention
The amdgpu-kernel calling convention was reverted in commit f6b21e90d1 (#120495 and https://github.com/rust-lang/rust-analyzer/pull/16463) due to inactivity in the amdgpu target.
Introduce a `gpu-kernel` calling convention that translates to `ptx_kernel` or `amdgpu_kernel`, depending on the target that rust compiles for.
Tracking issue: #135467
amdgpu target tracking issue: #135024
The amdgpu-kernel calling convention was reverted in commit
f6b21e90d1 due to inactivity in the amdgpu
target.
Introduce a `gpu-kernel` calling convention that translates to
`ptx_kernel` or `amdgpu_kernel`, depending on the target that rust
compiles for.
The initial naming of "Abi" was an awful mistake, conveying wrong ideas
about how psABIs worked and even more about what the enum meant.
It was only meant to represent the way the value would be described to
a codegen backend as it was lowered to that intermediate representation.
It was never meant to mean anything about the actual psABI handling!
The conflation is because LLVM typically will associate a certain form
with a certain ABI, but even that does not hold when the special cases
that actually exist arise, plus the IR annotations that modify the ABI.
Reframe `rustc_abi::Abi` as the `BackendRepr` of the type, and rename
`BackendRepr::Aggregate` as `BackendRepr::Memory`. Unfortunately, due to
the persistent misunderstandings, this too is now incorrect:
- Scattered ABI-relevant code is entangled with BackendRepr
- We do not always pre-compute a correct BackendRepr that reflects how
we "actually" want this value to be handled, so we leave the backend
interface to also inject various special-cases here
- In some cases `BackendRepr::Memory` is a "real" aggregate, but in
others it is in fact using memory, and in some cases it is a scalar!
Our rustc-to-backend lowering code handles this sort of thing right now.
That will eventually be addressed by lifting duplicated lowering code
to either rustc_codegen_ssa or rustc_target as appropriate.
