[Coroutines] Walk inlinedAt recursively to create legal DILabels

[Dinistro]

This commit resolves a defect in the creation of DILabels for suspend points. While a previous change introduced support for inlined locations, it did not consider that a location might originate from multiple inlinings. Therefore, we extend this to walk iteratively through all inlinedAt locations to get to the root.

[llvmbot]

@llvm/pr-subscribers-llvm-transforms

@llvm/pr-subscribers-coroutines

Author: Christian Ulmann (Dinistro)

Changes

This commit resolves a defect in the creation of DILabels for suspend points. While a previous change introduced support for inlined locations, it did not consider that a location might originate from multiple inlinings. Therefore, we extend this to walk iteratively through all inlinedAt locations to get to the root.

---

Full diff: https://github.com/llvm/llvm-project/pull/157099.diff

2 Files Affected:

• (modified) llvm/lib/Transforms/Coroutines/CoroSplit.cpp (+9-7)
• (modified) llvm/test/Transforms/Coroutines/coro-split-dbg-labels-inlined.ll (+7-1)

diff --git a/llvm/lib/Transforms/Coroutines/CoroSplit.cpp b/llvm/lib/Transforms/Coroutines/CoroSplit.cpp index 88b2bd9aa2046..02c38d02cff64 100644 --- a/llvm/lib/Transforms/Coroutines/CoroSplit.cpp +++ b/llvm/lib/Transforms/Coroutines/CoroSplit.cpp @@ -1568,13 +1568,15 @@ struct SwitchCoroutineSplitter { if (DebugLoc SuspendLoc = S->getDebugLoc()) { std::string LabelName = ("__coro_resume_" + Twine(SuspendIndex)).str(); - // Take the "inlined at" location, if present. This is mandatory as - // the DILabel insertion checks that the scopes of label and the - // attached location match. This is not the case when the suspend - // location has been inlined due to pointing to the original scope. - DILocation *DILoc = SuspendLoc->getInlinedAt(); - if (!DILoc) - DILoc = SuspendLoc; + // Take the "inlined at" location recursively, if present. This is + // mandatory as the DILabel insertion checks that the scopes of label + // and the attached location match. This is not the case when the + // suspend location has been inlined due to pointing to the original + // scope. + DILocation *DILoc = SuspendLoc; + while (DILocation *InlinedAt = DILoc->getInlinedAt()) + DILoc = InlinedAt; + DILabel *ResumeLabel = DBuilder.createLabel(DIS, LabelName, DILoc->getFile(), SuspendLoc.getLine(), SuspendLoc.getCol(), diff --git a/llvm/test/Transforms/Coroutines/coro-split-dbg-labels-inlined.ll b/llvm/test/Transforms/Coroutines/coro-split-dbg-labels-inlined.ll index 0905f5981502c..e9737b62b0b8f 100644 --- a/llvm/test/Transforms/Coroutines/coro-split-dbg-labels-inlined.ll +++ b/llvm/test/Transforms/Coroutines/coro-split-dbg-labels-inlined.ll @@ -1,5 +1,8 @@ ; RUN: opt %s -passes='cgscc(coro-split)' -S | FileCheck %s +; Verifies that suspend points with inlined locations are handled properly, +; i.e., that their debug labels point to the correct subprogram. + source_filename = "coro.c" ; Function Attrs: nounwind uwtable @@ -96,4 +99,7 @@ attributes #4 = { argmemonly nounwind readonly } !41 = !DILocation(line: 17, column: 1, scope: !16) !100 = distinct !DISubprogram(name: "callee", scope: !1, file: !1, line: 8, type: !17, scopeLine: 4, isOptimized: true, unit: !0, retainedNodes: !2) -!101 = !DILocation(line: 12, column: 6, scope: !16) +!101 = !DILocation(line: 42, column: 6, scope: !102, inlinedAt: !103) + +!102 = distinct !DISubprogram(name: "callee_recursive", scope: !1, file: !1, line: 8, type: !17, scopeLine: 4, isOptimized: true, unit: !0, retainedNodes: !2) +!103 = !DILocation(line: 12, column: 6, scope: !16) 

[gysit]

LGTM