coverage: Rename add_unused_functions to synthesize_unused_functions

Author: Zalathar

compiler/rustc_codegen_llvm/src/coverageinfo/mapgen.rs

@@ -40,7 +40,7 @@ pub fn finalize(cx: &CodegenCx<'_, '_>) {
     // MIR `Coverage` code regions to the `function_coverage_map`, before calling
     // `ctx.take_function_coverage_map()`.
     if cx.codegen_unit.is_code_coverage_dead_code_cgu() {
-        unused::add_unused_functions(cx);
+        unused::synthesize_unused_functions(cx);
     }
 
     let function_coverage_map = match cx.coverage_context() {

compiler/rustc_codegen_llvm/src/coverageinfo/unused.rs

@@ -30,7 +30,7 @@ use rustc_middle::ty::{self, GenericArgs, Instance, Ty};
 /// "code coverage dead code cgu" during the partitioning process. This prevents us from generating
 /// code regions for the same function more than once which can lead to linker errors regarding
 /// duplicate symbols.
-pub(crate) fn add_unused_functions(cx: &CodegenCx<'_, '_>) {
+pub(crate) fn synthesize_unused_functions(cx: &CodegenCx<'_, '_>) {
     assert!(cx.codegen_unit.is_code_coverage_dead_code_cgu());
 
     let tcx = cx.tcx;