src/test/run-make-fulldeps/hotplug_codegen_backend/the_backend.rs

   1 #![feature(rustc_private)]
   2 #![deny(warnings)]
   3
   4 extern crate rustc_codegen_ssa;
   5 extern crate rustc_errors;
   6 extern crate rustc_middle;
   7 extern crate rustc_data_structures;
   8 extern crate rustc_driver;
   9 extern crate rustc_hir;
  10 extern crate rustc_session;
  11 extern crate rustc_span;
  12 extern crate rustc_symbol_mangling;
  13 extern crate rustc_target;
  14
  15 use rustc_codegen_ssa::back::linker::LinkerInfo;
  16 use rustc_codegen_ssa::traits::CodegenBackend;
  17 use rustc_codegen_ssa::{CodegenResults, CrateInfo};
  18 use rustc_data_structures::fx::FxHashMap;
  19 use rustc_errors::ErrorReported;
  20 use rustc_middle::dep_graph::{WorkProduct, WorkProductId};
  21 use rustc_middle::middle::cstore::EncodedMetadata;
  22 use rustc_middle::ty::TyCtxt;
  23 use rustc_session::config::OutputFilenames;
  24 use rustc_session::Session;
  25 use std::any::Any;
  26
  27 struct TheBackend;
  28
  29 impl CodegenBackend for TheBackend {
  30     fn codegen_crate<'a, 'tcx>(
  31         &self,
  32         tcx: TyCtxt<'tcx>,
  33         metadata: EncodedMetadata,
  34         _need_metadata_module: bool,
  35     ) -> Box<dyn Any> {
  36         Box::new(CodegenResults {
  37             modules: vec![],
  38             allocator_module: None,
  39             metadata_module: None,
  40             metadata,
  41             linker_info: LinkerInfo::new(tcx, "fake_target_cpu".to_string()),
  42             crate_info: CrateInfo::new(tcx),
  43         })
  44     }
  45
  46     fn join_codegen(
  47         &self,
  48         ongoing_codegen: Box<dyn Any>,
  49         _sess: &Session,
  50     ) -> Result<(CodegenResults, FxHashMap<WorkProductId, WorkProduct>), ErrorReported> {
  51         let codegen_results = ongoing_codegen
  52             .downcast::<CodegenResults>()
  53             .expect("in join_codegen: ongoing_codegen is not a CodegenResults");
  54         Ok((*codegen_results, FxHashMap::default()))
  55     }
  56
  57     fn link(
  58         &self,
  59         sess: &Session,
  60         codegen_results: CodegenResults,
  61         outputs: &OutputFilenames,
  62     ) -> Result<(), ErrorReported> {
  63         use rustc_session::{config::CrateType, output::out_filename};
  64         use std::io::Write;
  65         let crate_name = codegen_results.crate_info.local_crate_name;
  66         for &crate_type in sess.opts.crate_types.iter() {
  67             if crate_type != CrateType::Rlib {
  68                 sess.fatal(&format!("Crate type is {:?}", crate_type));
  69             }
  70             let output_name = out_filename(sess, crate_type, &outputs, &*crate_name.as_str());
  71             let mut out_file = ::std::fs::File::create(output_name).unwrap();
  72             write!(out_file, "This has been \"compiled\" successfully.").unwrap();
  73         }
  74         Ok(())
  75     }
  76 }
  77
  78 /// This is the entrypoint for a hot plugged rustc_codegen_llvm
  79 #[no_mangle]
  80 pub fn __rustc_codegen_backend() -> Box<dyn CodegenBackend> {
  81     Box::new(TheBackend)
  82 }