coverage: Rename CrateCoverageContext to CguCoverageContext

This context is stored in `CodegenCx`, which makes it per-CGU rather than
per-crate. A single crate can have multiple CGUs.

Author: Zalathar

compiler/rustc_codegen_llvm/src/context.rs

@@ -82,8 +82,8 @@ pub(crate) struct CodegenCx<'ll, 'tcx> {
 
     pub isize_ty: &'ll Type,
 
-    /// Extra codegen state needed when coverage instrumentation is enabled.
-    pub coverage_cx: Option<coverageinfo::CrateCoverageContext<'ll, 'tcx>>,
+    /// Extra per-CGU codegen state needed when coverage instrumentation is enabled.
+    pub coverage_cx: Option<coverageinfo::CguCoverageContext<'ll, 'tcx>>,
     pub dbg_cx: Option<debuginfo::CodegenUnitDebugContext<'ll, 'tcx>>,
 
     eh_personality: Cell<Option<&'ll Value>>,
@@ -525,7 +525,7 @@ impl<'ll, 'tcx> CodegenCx<'ll, 'tcx> {
         let (llcx, llmod) = (&*llvm_module.llcx, llvm_module.llmod());
 
         let coverage_cx =
-            tcx.sess.instrument_coverage().then(coverageinfo::CrateCoverageContext::new);
+            tcx.sess.instrument_coverage().then(coverageinfo::CguCoverageContext::new);
 
         let dbg_cx = if tcx.sess.opts.debuginfo != DebugInfo::None {
             let dctx = debuginfo::CodegenUnitDebugContext::new(llmod);
@@ -576,7 +576,7 @@ impl<'ll, 'tcx> CodegenCx<'ll, 'tcx> {
     /// Extra state that is only available when coverage instrumentation is enabled.
     #[inline]
     #[track_caller]
-    pub(crate) fn coverage_cx(&self) -> &coverageinfo::CrateCoverageContext<'ll, 'tcx> {
+    pub(crate) fn coverage_cx(&self) -> &coverageinfo::CguCoverageContext<'ll, 'tcx> {
         self.coverage_cx.as_ref().expect("only called when coverage instrumentation is enabled")
     }
 

compiler/rustc_codegen_llvm/src/coverageinfo/mod.rs

@@ -21,8 +21,8 @@ mod llvm_cov;
 pub(crate) mod map_data;
 mod mapgen;
 
-/// A context object for maintaining all state needed by the coverageinfo module.
-pub(crate) struct CrateCoverageContext<'ll, 'tcx> {
+/// Extra per-CGU context/state needed for coverage instrumentation.
+pub(crate) struct CguCoverageContext<'ll, 'tcx> {
     /// Coverage data for each instrumented function identified by DefId.
     pub(crate) function_coverage_map:
         RefCell<FxIndexMap<Instance<'tcx>, FunctionCoverageCollector<'tcx>>>,
@@ -32,7 +32,7 @@ pub(crate) struct CrateCoverageContext<'ll, 'tcx> {
     covfun_section_name: OnceCell<CString>,
 }
 
-impl<'ll, 'tcx> CrateCoverageContext<'ll, 'tcx> {
+impl<'ll, 'tcx> CguCoverageContext<'ll, 'tcx> {
     pub(crate) fn new() -> Self {
         Self {
             function_coverage_map: Default::default(),