[KeyInstr][Inline] Don't propagate atoms to inlined nodebug instructions

[OCHyams]

No description provided.

[OCHyams]

• [NFC][KeyInstr][Clang] Add some additional tests #134654
• [KeyInstr][Clang] Coerced store atoms #134653
• [KeyInstr][Clang] Ret atom #134652
• [KeyIntsr][Clang] Builtins alloca auto-init atom #134651
• [KeyInstr][Clang] Assign matrix element atom #134650
• [KeyInstr][Clang] Assign vector element atom #134649
• [KeyInstr][Clang] Bitfield atom #134648
• [KeyInstr][Clang] For range stmt atoms #134647
• [KeyInstr][Clang] For stmt atom #134646
• [KeyInstr][Clang] While stmt atom #134645
• [KeyInstr][Clang] Do stmt atom #134644
• [KeyInstr][Clang] Switch stmt atom #134643
• [KeyInstr][Clang] If stmt atom #134642
• [KeyInstr][Clang] Catch variable init atom #134641
• [KeyInstr][Clang] Member initalization atom #134640
• [KeyInstr][Clang] Aggregate init + copy #134639
• [KeyInstr] Complex assignment atoms #134638
• [KeyInstr][Clang] Assignment atom group #134637
• [KeyInstr][Clang] Static variable init atom #134636
• [KeyInstr][Clang] Agg init atom #134635
• [Clang][NFC] Move some static functions into CodeGenFunction #134634
• [KeyInstr][Clang] Scalar init atom #134633
• [KeyInstr][Clang] Add ApplyAtomGroup #134632
• [KeyInstr][Clang] Add Clang option -g[no-]key-instructions #134627
• [KeyInstr][DwarfDebug] Add is_stmt emission support #133495
• [KeyInstr] Add MIR parser support #133494
• [KeyInstr] Remap cloned PHIs in BreakCriticalEdges #133493
• Propagate DebugLocs on phis in BreakCriticalEdges #133492
• [KeyInstr][LoopUnswitch] Remap cloned instructions' atoms #133491
• [KeyInstr][LoopRotate] Remap atoms of duplicated instructions #133490
• [KeyInstr][LoopUnroll] Remap atoms while unrolling #133489
• [KeyInstr][JumpThreading] Remap atoms duping bb with cond br on phi into pred #133488
• [KeyInstr][JumpThreading] Remap atoms after threading #133487
• [KeyInstr][JumpThreading] Remap atoms in blocks duplicated for threading #133486
• [KeyInstr][Inline] Don't propagate atoms to inlined nodebug instructions #133485 👈 (View in Graphite)
• [KeyInstr][SimplifyCFG] Remap atoms after duplication for threading #133484
• [KeyInstr][debugify] Add --debugify-atoms to add key instructions metadata #133483
• [KeyInstr][SimplifyCFG] Remap atoms when folding br to common succ into pred #133482
• [KeyInstr] Inline atom info #133481
• [KeyInstr] Merge atoms in DILocation::getMergedLocation #133480
• [NFC][KeyInstr] Add Atom Group (re)mapping #133479
• [KeyInstr] Add Atom Group waterline to LLVMContext #133478
• [KeyInstr] Add fields to DILocation behind compile time flag #133477
• main

This stack of pull requests is managed by Graphite. Learn more about stacking.

[llvmbot]

@llvm/pr-subscribers-debuginfo
@llvm/pr-subscribers-llvm-transforms

@llvm/pr-subscribers-llvm-ir

Author: Orlando Cazalet-Hyams (OCHyams)

Changes

---

Full diff: https://github.com/llvm/llvm-project/pull/133485.diff

3 Files Affected:

• (modified) llvm/include/llvm/IR/DebugInfoMetadata.h (+7)
• (modified) llvm/lib/Transforms/Utils/InlineFunction.cpp (+2-2)
• (added) llvm/test/DebugInfo/KeyInstructions/Generic/inline-nodbg.ll (+43)

diff --git a/llvm/include/llvm/IR/DebugInfoMetadata.h b/llvm/include/llvm/IR/DebugInfoMetadata.h
index ede3bda5c68f4..243ea5e1236ad 100644
--- a/llvm/include/llvm/IR/DebugInfoMetadata.h
+++ b/llvm/include/llvm/IR/DebugInfoMetadata.h
@@ -2145,6 +2145,13 @@ class DILocation : public MDNode {
     return 0;
   }
 
+  const DILocation *getOrCloneWithoutAtom() const {
+    if (!getAtomGroup() && !getAtomRank())
+      return this;
+    return get(getContext(), getLine(), getColumn(), getScope(), getInlinedAt(),
+               isImplicitCode());
+  }
+
   // Disallow replacing operands.
   void replaceOperandWith(unsigned I, Metadata *New) = delete;
 
diff --git a/llvm/lib/Transforms/Utils/InlineFunction.cpp b/llvm/lib/Transforms/Utils/InlineFunction.cpp
index 9202451f5726d..fa4f21480b94d 100644
--- a/llvm/lib/Transforms/Utils/InlineFunction.cpp
+++ b/llvm/lib/Transforms/Utils/InlineFunction.cpp
@@ -1821,9 +1821,9 @@ static DebugLoc inlineDebugLoc(DebugLoc OrigDL, DILocation *InlinedAt,
 /// to encode location where these instructions are inlined.
 static void fixupLineNumbers(Function *Fn, Function::iterator FI,
                              Instruction *TheCall, bool CalleeHasDebugInfo) {
-  const DebugLoc &TheCallDL = TheCall->getDebugLoc();
-  if (!TheCallDL)
+  if (!TheCall->getDebugLoc())
     return;
+  DebugLoc TheCallDL = TheCall->getDebugLoc().get()->getOrCloneWithoutAtom();
 
   auto &Ctx = Fn->getContext();
   DILocation *InlinedAtNode = TheCallDL;
diff --git a/llvm/test/DebugInfo/KeyInstructions/Generic/inline-nodbg.ll b/llvm/test/DebugInfo/KeyInstructions/Generic/inline-nodbg.ll
new file mode 100644
index 0000000000000..33f7f673d91c3
--- /dev/null
+++ b/llvm/test/DebugInfo/KeyInstructions/Generic/inline-nodbg.ll
@@ -0,0 +1,43 @@
+; RUN: opt %s -passes=inline -S -o - | FileCheck %s
+
+;; $ cat test.cpp
+;; int g;
+;; [[clang::always_inline, gnu::nodebug]]  void a() { g = 1; }
+;; void b() { a(); }
+;;
+;; Check the inlined instructions don't inherit the call's atom info.
+;; FIXME: Perhaps we want to do actually do that, to preserve existing
+;; behaviour? Unclear what's best.
+
+; CHECK: _Z1bv()
+; CHECK: store i32 1, ptr @g, align 4, !dbg [[DBG:!.*]]
+; CHECK: [[DBG]] = !DILocation(line: 3, scope: ![[#]])
+
+@g = hidden global i32 0, align 4
+
+define hidden void @_Z1av() {
+entry:
+  store i32 1, ptr @g, align 4
+  ret void
+}
+
+define hidden void @_Z1bv() !dbg !15 {
+entry:
+  call void @_Z1av(), !dbg !18
+  ret void, !dbg !19
+}
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!2, !3}
+!llvm.ident = !{!10}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus_17, file: !1, producer: "clang version 19.0.0", isOptimized: true, runtimeVersion: 0, emissionKind: LineTablesOnly, splitDebugInlining: false, nameTableKind: None)
+!1 = !DIFile(filename: "test.cpp", directory: "/")
+!2 = !{i32 7, !"Dwarf Version", i32 5}
+!3 = !{i32 2, !"Debug Info Version", i32 3}
+!10 = !{!"clang version 19.0.0"}
+!15 = distinct !DISubprogram(name: "b", scope: !1, file: !1, line: 3, type: !16, scopeLine: 3, flags: DIFlagPrototyped | DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0)
+!16 = !DISubroutineType(types: !17)
+!17 = !{}
+!18 = !DILocation(line: 3, scope: !15, atomGroup: 1, atomRank: 1)
+!19 = !DILocation(line: 3, scope: !15, atomGroup: 2, atomRank: 1)

[SLTozer]

I think conceptually there is some space for copying atom group/rank to the inlined instructions, giving the instruction(s) that produce the return value (if any) the highest precedence. This would be a separate feature however, and this behaviour seems fine to me as a first pass; minor inline comment.

[SLTozer]

I think this could just be "getWithoutAtom", it's already implied with DIMetadata that "get" means "find me an existing metadata or create a new one".

[jmorse]

LGTM with nit

[jmorse]

Comment on why this is necessary desired.