From 05e1f0d7691860e44e87595e8a6a572f7c14d605 Mon Sep 17 00:00:00 2001 From: Eric Holk Date: Thu, 13 Jan 2022 15:31:36 -0800 Subject: [PATCH 1/2] Generate more precise generator names Currently all generators are named with a `generator$N` suffix, regardless of where they come from. This means an `async fn` shows up as a generator in stack traces, which can be surprising to async programmers since they should not need to know that async functions are implementated using generators. This change generators a different name depending on the generator kind, allowing us to tell whether the generator is the result of an async block, an async closure, an async fn, or a plain generator. --- compiler/rustc_codegen_ssa/src/debuginfo/type_names.rs | 10 ++++++++-- src/test/codegen/async-fn-debug-msvc.rs | 2 +- 2 files changed, 9 insertions(+), 3 deletions(-) diff --git a/compiler/rustc_codegen_ssa/src/debuginfo/type_names.rs b/compiler/rustc_codegen_ssa/src/debuginfo/type_names.rs index 9ecab82dd2e9e..61322a6e556ed 100644 --- a/compiler/rustc_codegen_ssa/src/debuginfo/type_names.rs +++ b/compiler/rustc_codegen_ssa/src/debuginfo/type_names.rs @@ -519,12 +519,18 @@ fn push_unqualified_item_name( output.push_str(tcx.crate_name(def_id.krate).as_str()); } DefPathData::ClosureExpr if tcx.generator_kind(def_id).is_some() => { + let key = match tcx.generator_kind(def_id).unwrap() { + hir::GeneratorKind::Async(hir::AsyncGeneratorKind::Block) => "async_block", + hir::GeneratorKind::Async(hir::AsyncGeneratorKind::Closure) => "async_closure", + hir::GeneratorKind::Async(hir::AsyncGeneratorKind::Fn) => "async_fn", + hir::GeneratorKind::Gen => "generator", + }; // Generators look like closures, but we want to treat them differently // in the debug info. if cpp_like_debuginfo(tcx) { - write!(output, "generator${}", disambiguated_data.disambiguator).unwrap(); + write!(output, "{}${}", key, disambiguated_data.disambiguator).unwrap(); } else { - write!(output, "{{generator#{}}}", disambiguated_data.disambiguator).unwrap(); + write!(output, "{{{}#{}}}", key, disambiguated_data.disambiguator).unwrap(); } } _ => match disambiguated_data.data.name() { diff --git a/src/test/codegen/async-fn-debug-msvc.rs b/src/test/codegen/async-fn-debug-msvc.rs index 0c16b9ad3ab51..bb0db9d3d8514 100644 --- a/src/test/codegen/async-fn-debug-msvc.rs +++ b/src/test/codegen/async-fn-debug-msvc.rs @@ -17,7 +17,7 @@ async fn async_fn_test() { // FIXME: No way to reliably check the filename. // CHECK-DAG: [[ASYNC_FN:!.*]] = !DINamespace(name: "async_fn_test" -// CHECK-DAG: [[GEN:!.*]] = !DICompositeType(tag: DW_TAG_union_type, name: "generator$0" +// CHECK-DAG: [[GEN:!.*]] = !DICompositeType(tag: DW_TAG_union_type, name: "async_fn$0" // CHECK: {{!.*}} = !DIDerivedType(tag: DW_TAG_member, name: "variant0", scope: [[GEN]], // For brevity, we only check the struct name and members of the last variant. // CHECK-SAME: file: [[FILE:![0-9]*]], line: 11, From a1173cf074ad557e8c896680537969f6b6942368 Mon Sep 17 00:00:00 2001 From: Eric Holk Date: Thu, 13 Jan 2022 15:56:51 -0800 Subject: [PATCH 2/2] Fix non-MSVC test --- src/test/codegen/async-fn-debug.rs | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/src/test/codegen/async-fn-debug.rs b/src/test/codegen/async-fn-debug.rs index 39319a3ea722c..f456f7ffc0fba 100644 --- a/src/test/codegen/async-fn-debug.rs +++ b/src/test/codegen/async-fn-debug.rs @@ -17,7 +17,7 @@ async fn async_fn_test() { // FIXME: No way to reliably check the filename. // CHECK-DAG: [[ASYNC_FN:!.*]] = !DINamespace(name: "async_fn_test" -// CHECK-DAG: [[GEN:!.*]] = !DICompositeType(tag: DW_TAG_structure_type, name: "{generator#0}", scope: [[ASYNC_FN]] +// CHECK-DAG: [[GEN:!.*]] = !DICompositeType(tag: DW_TAG_structure_type, name: "{async_fn#0}", scope: [[ASYNC_FN]] // CHECK: [[VARIANT:!.*]] = !DICompositeType(tag: DW_TAG_variant_part, scope: [[ASYNC_FN]], // CHECK-NOT: flags: DIFlagArtificial // CHECK-SAME: discriminator: [[DISC:![0-9]*]]