1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
use super::write::WriteBackendMethods;
use super::CodegenObject;
use crate::back::write::TargetMachineFactoryFn;
use crate::{CodegenResults, ModuleCodegen};

use rustc_ast::expand::allocator::AllocatorKind;
use rustc_data_structures::fx::FxHashMap;
use rustc_errors::ErrorReported;
use rustc_metadata::EncodedMetadata;
use rustc_middle::dep_graph::{WorkProduct, WorkProductId};
use rustc_middle::ty::layout::{FnAbiOf, HasTyCtxt, LayoutOf, TyAndLayout};
use rustc_middle::ty::query::{ExternProviders, Providers};
use rustc_middle::ty::{Ty, TyCtxt};
use rustc_session::{
    config::{self, OutputFilenames, PrintRequest},
    cstore::MetadataLoaderDyn,
    Session,
};
use rustc_span::symbol::Symbol;
use rustc_target::abi::call::FnAbi;
use rustc_target::spec::Target;

pub use rustc_data_structures::sync::MetadataRef;

use std::any::Any;

pub trait BackendTypes {
    type Value: CodegenObject;
    type Function: CodegenObject;

    type BasicBlock: Copy;
    type Type: CodegenObject;
    type Funclet;

    // FIXME(eddyb) find a common convention for all of the debuginfo-related
    // names (choose between `Dbg`, `Debug`, `DebugInfo`, `DI` etc.).
    type DIScope: Copy;
    type DILocation: Copy;
    type DIVariable: Copy;
}

pub trait Backend<'tcx>:
    Sized
    + BackendTypes
    + HasTyCtxt<'tcx>
    + LayoutOf<'tcx, LayoutOfResult = TyAndLayout<'tcx>>
    + FnAbiOf<'tcx, FnAbiOfResult = &'tcx FnAbi<'tcx, Ty<'tcx>>>
{
}

impl<'tcx, T> Backend<'tcx> for T where
    Self: BackendTypes
        + HasTyCtxt<'tcx>
        + LayoutOf<'tcx, LayoutOfResult = TyAndLayout<'tcx>>
        + FnAbiOf<'tcx, FnAbiOfResult = &'tcx FnAbi<'tcx, Ty<'tcx>>>
{
}

pub trait CodegenBackend {
    fn init(&self, _sess: &Session) {}
    fn print(&self, _req: PrintRequest, _sess: &Session) {}
    fn target_features(&self, _sess: &Session) -> Vec<Symbol> {
        vec![]
    }
    fn print_passes(&self) {}
    fn print_version(&self) {}

    /// If this plugin provides additional builtin targets, provide the one enabled by the options here.
    /// Be careful: this is called *before* init() is called.
    fn target_override(&self, _opts: &config::Options) -> Option<Target> {
        None
    }

    /// The metadata loader used to load rlib and dylib metadata.
    ///
    /// Alternative codegen backends may want to use different rlib or dylib formats than the
    /// default native static archives and dynamic libraries.
    fn metadata_loader(&self) -> Box<MetadataLoaderDyn> {
        Box::new(crate::back::metadata::DefaultMetadataLoader)
    }

    fn provide(&self, _providers: &mut Providers) {}
    fn provide_extern(&self, _providers: &mut ExternProviders) {}
    fn codegen_crate<'tcx>(
        &self,
        tcx: TyCtxt<'tcx>,
        metadata: EncodedMetadata,
        need_metadata_module: bool,
    ) -> Box<dyn Any>;

    /// This is called on the returned `Box<dyn Any>` from `codegen_backend`
    ///
    /// # Panics
    ///
    /// Panics when the passed `Box<dyn Any>` was not returned by `codegen_backend`.
    fn join_codegen(
        &self,
        ongoing_codegen: Box<dyn Any>,
        sess: &Session,
    ) -> Result<(CodegenResults, FxHashMap<WorkProductId, WorkProduct>), ErrorReported>;

    /// This is called on the returned `Box<dyn Any>` from `join_codegen`
    ///
    /// # Panics
    ///
    /// Panics when the passed `Box<dyn Any>` was not returned by `join_codegen`.
    fn link(
        &self,
        sess: &Session,
        codegen_results: CodegenResults,
        outputs: &OutputFilenames,
    ) -> Result<(), ErrorReported>;
}

pub trait ExtraBackendMethods: CodegenBackend + WriteBackendMethods + Sized + Send + Sync {
    fn new_metadata(&self, sess: TyCtxt<'_>, mod_name: &str) -> Self::Module;
    fn write_compressed_metadata<'tcx>(
        &self,
        tcx: TyCtxt<'tcx>,
        metadata: &EncodedMetadata,
        llvm_module: &mut Self::Module,
    );
    fn codegen_allocator<'tcx>(
        &self,
        tcx: TyCtxt<'tcx>,
        module_llvm: &mut Self::Module,
        module_name: &str,
        kind: AllocatorKind,
        has_alloc_error_handler: bool,
    );
    /// This generates the codegen unit and returns it along with
    /// a `u64` giving an estimate of the unit's processing cost.
    fn compile_codegen_unit(
        &self,
        tcx: TyCtxt<'_>,
        cgu_name: Symbol,
    ) -> (ModuleCodegen<Self::Module>, u64);
    fn target_machine_factory(
        &self,
        sess: &Session,
        opt_level: config::OptLevel,
    ) -> TargetMachineFactoryFn<Self>;
    fn target_cpu<'b>(&self, sess: &'b Session) -> &'b str;
    fn tune_cpu<'b>(&self, sess: &'b Session) -> Option<&'b str>;

    fn spawn_thread<F, T>(_time_trace: bool, f: F) -> std::thread::JoinHandle<T>
    where
        F: FnOnce() -> T,
        F: Send + 'static,
        T: Send + 'static,
    {
        std::thread::spawn(f)
    }

    fn spawn_named_thread<F, T>(
        _time_trace: bool,
        name: String,
        f: F,
    ) -> std::io::Result<std::thread::JoinHandle<T>>
    where
        F: FnOnce() -> T,
        F: Send + 'static,
        T: Send + 'static,
    {
        std::thread::Builder::new().name(name).spawn(f)
    }
}