* Introduce a `TargetFrontendConfig` type.
`TargetFrontendConfig` is information specific to the target which is
provided to frontends to allow them to produce Cranelift IR for the
target. Currently this includes the pointer size and the default calling
convention.
The default calling convention is now inferred from the target, rather
than being a setting. cranelift-native is now just a provider of target
information, rather than also being a provider of settings, which gives
it a clearer role.
And instead of having cranelift-frontend routines require the whole
`TargetIsa`, just require the `TargetFrontendConfig`, and add a way to
get the `TargetFrontendConfig` from a `Module`.
Fixes#529.
Fixes#555.
This switches from a custom list of architectures to use the
target-lexicon crate.
- "set is_64bit=1; isa x86" is replaced with "target x86_64", and
similar for other architectures, and the `is_64bit` flag is removed
entirely.
- The `is_compressed` flag is removed too; it's no longer being used to
control REX prefixes on x86-64, ARM and Thumb are separate
architectures in target-lexicon, and we can figure out how to
select RISC-V compressed encodings when we're ready.
* Update to rustfmt-preview.
* Run "cargo fmt --all" with rustfmt 0.4.1.
rustfmt 0.4.1 is the latest release of rustfmt-preview available on the
stable channel.
* Fix a long line that rustfmt 0.4.1 can't handle.
* Remove unneeded commas left behind by rustfmt.
* initial set of work for windows fastcall (x64) call convention
- call conventions: rename `fastcall` to `windows_fastcall`
- add initial set of filetests
- ensure arguments are written after the shadow space/store (offset-wise)
The shadow space available before the arguments (range 0..32)
is not used as spill space yet.
* address review feedback
Add a calling-convention setting to the `Flags` used as part of the
`TargetIsa`. This allows Cretonne code that generates calls to use the
correct convention, such as when emitting libcalls during legalization
or when the wasm frontend is decoding functions. This setting can be
overridden per-function.
This also adds "fast", "cold", and "fastcall" conventions, with "fast"
as the new default. Note that "fast" and "cold" are not intended to be
ABI-compatible across Cretonne versions.
This will also ensure Windows users will get an `unimplemented!` rather
than silent calling-convention mismatches, which reflects the fact that
Windows calling conventions are not yet implemented.
This also renames SpiderWASM, which isn't camel-case, to Baldrdash,
which is, and which is also a more relevant name.
