[clang] [llvm] [llvm][DebugInfo][clang] Finalize all declaration subprograms in DIBuilder::finalize() (PR #139914)

[via cfe-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->
@llvm/pr-subscribers-clang-codegen

@llvm/pr-subscribers-debuginfo

Author: Vladislav Dzhidzhoev (dzhidzhoev)

<details>
<summary>Changes</summary>

DIBuilder began tracking definition subprograms and finalizing them in `DIBuilder::finalize()` in eb1bb4e419.
Currently, `finalizeSubprogram()` attaches local variables and labels to the `retainedNodes:` field of a corresponding subprogram.

After 75819aedf, the definition and some declaration subprograms are finalized in `DIBuilder::finalize()`:
`AllSubprograms` holds references to definition subprograms.
`RetainValues` holds references to declaration subprograms.
For DISubprogram elements of both variables, `finalizeSubprogram()` was called there.

However, `retainTypes()` is not necessarily called for every declaration subprogram (as in 40a3fcb0).

DIBuilder clients may also want to attach DILocalVariables to declaration subprograms, for example, in 58bdf8f9a8.

Thus, the `finalizeSubprogram()` function is called for all definition subprograms in `DIBuilder::finalize()` because they are stored in the `AllSubprograms` during the `CreateFunction(isDefinition: true)` call. But for the declaration subprograms, it should be called manually.

I think this feature of the DIBuilder interface is somewhat unclear, and `AllSubprograms` could just be used for holding and finalizing all DISubprograms.

---
Full diff: https://github.com/llvm/llvm-project/pull/139914.diff


2 Files Affected:

- (modified) clang/lib/CodeGen/CGDebugInfo.cpp (+1-3) 
- (modified) llvm/lib/IR/DIBuilder.cpp (+2-4) 


``````````diff
diff --git a/clang/lib/CodeGen/CGDebugInfo.cpp b/clang/lib/CodeGen/CGDebugInfo.cpp
index 2a11eebf1b682..bac113289f507 100644
--- a/clang/lib/CodeGen/CGDebugInfo.cpp
+++ b/clang/lib/CodeGen/CGDebugInfo.cpp
@@ -4611,7 +4611,7 @@ void CGDebugInfo::EmitFunctionDecl(GlobalDecl GD, SourceLocation Loc,
 
   // Preserve btf_decl_tag attributes for parameters of extern functions
   // for BPF target. The parameters created in this loop are attached as
-  // DISubprogram's retainedNodes in the subsequent finalizeSubprogram call.
+  // DISubprogram's retainedNodes in the DIBuilder::finalize() call.
   if (IsDeclForCallSite && CGM.getTarget().getTriple().isBPF()) {
     if (auto *FD = dyn_cast<FunctionDecl>(D)) {
       llvm::DITypeRefArray ParamTypes = STy->getTypeArray();
@@ -4628,8 +4628,6 @@ void CGDebugInfo::EmitFunctionDecl(GlobalDecl GD, SourceLocation Loc,
 
   if (IsDeclForCallSite)
     Fn->setSubprogram(SP);
-
-  DBuilder.finalizeSubprogram(SP);
 }
 
 void CGDebugInfo::EmitFuncDeclForCallSite(llvm::CallBase *CallOrInvoke,
diff --git a/llvm/lib/IR/DIBuilder.cpp b/llvm/lib/IR/DIBuilder.cpp
index 90da9f3acfe57..35e61caf9a241 100644
--- a/llvm/lib/IR/DIBuilder.cpp
+++ b/llvm/lib/IR/DIBuilder.cpp
@@ -940,8 +940,7 @@ DISubprogram *DIBuilder::createFunction(
       SPFlags, IsDefinition ? CUNode : nullptr, TParams, Decl, nullptr,
       ThrownTypes, Annotations, TargetFuncName);
 
-  if (IsDefinition)
-    AllSubprograms.push_back(Node);
+  AllSubprograms.push_back(Node);
   trackIfUnresolved(Node);
   return Node;
 }
@@ -978,8 +977,7 @@ DISubprogram *DIBuilder::createMethod(
       Flags, SPFlags, IsDefinition ? CUNode : nullptr, TParams, nullptr,
       nullptr, ThrownTypes);
 
-  if (IsDefinition)
-    AllSubprograms.push_back(SP);
+  AllSubprograms.push_back(SP);
   trackIfUnresolved(SP);
   return SP;
 }

``````````

</details>


https://github.com/llvm/llvm-project/pull/139914