rustc_codegen_ssa/traits/
backend.rs

1use std::any::Any;
2use std::hash::Hash;
3
4use rustc_ast::expand::allocator::AllocatorKind;
5use rustc_data_structures::fx::FxIndexMap;
6use rustc_data_structures::sync::{DynSend, DynSync};
7use rustc_metadata::EncodedMetadata;
8use rustc_metadata::creader::MetadataLoaderDyn;
9use rustc_middle::dep_graph::{WorkProduct, WorkProductId};
10use rustc_middle::ty::TyCtxt;
11use rustc_middle::util::Providers;
12use rustc_session::Session;
13use rustc_session::config::{self, OutputFilenames, PrintRequest};
14use rustc_span::Symbol;
15
16use super::CodegenObject;
17use super::write::WriteBackendMethods;
18use crate::back::archive::ArArchiveBuilderBuilder;
19use crate::back::link::link_binary;
20use crate::back::write::TargetMachineFactoryFn;
21use crate::{CodegenResults, ModuleCodegen, TargetConfig};
22
23pub trait BackendTypes {
24    type Value: CodegenObject + PartialEq;
25    type Metadata: CodegenObject;
26    type Function: CodegenObject;
27
28    type BasicBlock: Copy;
29    type Type: CodegenObject + PartialEq;
30    type Funclet;
31
32    // FIXME(eddyb) find a common convention for all of the debuginfo-related
33    // names (choose between `Dbg`, `Debug`, `DebugInfo`, `DI` etc.).
34    type DIScope: Copy + Hash + PartialEq + Eq;
35    type DILocation: Copy;
36    type DIVariable: Copy;
37}
38
39pub trait CodegenBackend {
40    /// Locale resources for diagnostic messages - a string the content of the Fluent resource.
41    /// Called before `init` so that all other functions are able to emit translatable diagnostics.
42    fn locale_resource(&self) -> &'static str;
43
44    fn init(&self, _sess: &Session) {}
45
46    fn print(&self, _req: &PrintRequest, _out: &mut String, _sess: &Session) {}
47
48    /// Collect target-specific options that should be set in `cfg(...)`, including
49    /// `target_feature` and support for unstable float types.
50    fn target_config(&self, _sess: &Session) -> TargetConfig {
51        TargetConfig {
52            target_features: vec![],
53            unstable_target_features: vec![],
54            // `true` is used as a default so backends need to acknowledge when they do not
55            // support the float types, rather than accidentally quietly skipping all tests.
56            has_reliable_f16: true,
57            has_reliable_f16_math: true,
58            has_reliable_f128: true,
59            has_reliable_f128_math: true,
60        }
61    }
62
63    fn print_passes(&self) {}
64
65    fn print_version(&self) {}
66
67    /// The metadata loader used to load rlib and dylib metadata.
68    ///
69    /// Alternative codegen backends may want to use different rlib or dylib formats than the
70    /// default native static archives and dynamic libraries.
71    fn metadata_loader(&self) -> Box<MetadataLoaderDyn> {
72        Box::new(crate::back::metadata::DefaultMetadataLoader)
73    }
74
75    fn provide(&self, _providers: &mut Providers) {}
76
77    fn codegen_crate<'tcx>(&self, tcx: TyCtxt<'tcx>) -> Box<dyn Any>;
78
79    /// This is called on the returned `Box<dyn Any>` from [`codegen_crate`](Self::codegen_crate)
80    ///
81    /// # Panics
82    ///
83    /// Panics when the passed `Box<dyn Any>` was not returned by [`codegen_crate`](Self::codegen_crate).
84    fn join_codegen(
85        &self,
86        ongoing_codegen: Box<dyn Any>,
87        sess: &Session,
88        outputs: &OutputFilenames,
89    ) -> (CodegenResults, FxIndexMap<WorkProductId, WorkProduct>);
90
91    /// This is called on the returned [`CodegenResults`] from [`join_codegen`](Self::join_codegen).
92    fn link(
93        &self,
94        sess: &Session,
95        codegen_results: CodegenResults,
96        metadata: EncodedMetadata,
97        outputs: &OutputFilenames,
98    ) {
99        link_binary(sess, &ArArchiveBuilderBuilder, codegen_results, metadata, outputs);
100    }
101}
102
103pub trait ExtraBackendMethods:
104    CodegenBackend + WriteBackendMethods + Sized + Send + Sync + DynSend + DynSync
105{
106    fn codegen_allocator<'tcx>(
107        &self,
108        tcx: TyCtxt<'tcx>,
109        module_name: &str,
110        kind: AllocatorKind,
111        alloc_error_handler_kind: AllocatorKind,
112    ) -> Self::Module;
113
114    /// This generates the codegen unit and returns it along with
115    /// a `u64` giving an estimate of the unit's processing cost.
116    fn compile_codegen_unit(
117        &self,
118        tcx: TyCtxt<'_>,
119        cgu_name: Symbol,
120    ) -> (ModuleCodegen<Self::Module>, u64);
121
122    fn target_machine_factory(
123        &self,
124        sess: &Session,
125        opt_level: config::OptLevel,
126        target_features: &[String],
127    ) -> TargetMachineFactoryFn<Self>;
128
129    fn spawn_named_thread<F, T>(
130        _time_trace: bool,
131        name: String,
132        f: F,
133    ) -> std::io::Result<std::thread::JoinHandle<T>>
134    where
135        F: FnOnce() -> T,
136        F: Send + 'static,
137        T: Send + 'static,
138    {
139        std::thread::Builder::new().name(name).spawn(f)
140    }
141
142    /// Returns `true` if this backend can be safely called from multiple threads.
143    ///
144    /// Defaults to `true`.
145    fn supports_parallel(&self) -> bool {
146        true
147    }
148}
rustc_codegen_ssa/traits/backend.rs

rustc_codegen_ssa/traits/
backend.rs
