2f8eeb2bba
Allow custom default address spaces and parse `p-` specifications in the datalayout string Some targets, such as CHERI, use as default an address space different from the "normal" default address space `0` (in the case of CHERI, [200 is used](https://www.cl.cam.ac.uk/techreports/UCAM-CL-TR-877.pdf)). Currently, `rustc` does not allow to specify custom address spaces and does not take into consideration [`p-` specifications in the datalayout string](https://llvm.org/docs/LangRef.html#langref-datalayout). This patch tries to mitigate these problems by allowing targets to define a custom default address space (while keeping the default value to address space `0`) and adding the code to parse the `p-` specifications in `rustc_abi`. The main changes are that `TargetDataLayout` now uses functions to refer to pointer-related informations, instead of having specific fields for the size and alignment of pointers in the default address space; furthermore, the two `pointer_size` and `pointer_align` fields in `TargetDataLayout` are replaced with an `FxHashMap` that holds info for all the possible address spaces, as parsed by the `p-` specifications. The potential performance drawbacks of not having ad-hoc fields for the default address space will be tested in this PR's CI run. r? workingjubilee |
||
|---|---|---|
| .. | ||
| callconv | ||
| extern_abi | ||
| layout | ||
| callconv.rs | ||
| canon_abi.rs | ||
| extern_abi.rs | ||
| layout.rs | ||
| lib.rs | ||
| tests.rs | ||