[llvm] [Utils] Extract ProcessSubprogramAttachment from CloneFunctionInto (PR #114537)

[Felipe de Azevedo Piovezan via llvm-commits]

================
@@ -137,6 +137,29 @@ void llvm::CloneFunctionAttributesInto(Function *NewFunc,
                          OldAttrs.getRetAttrs(), NewArgAttrs));
 }
 
+DISubprogram *llvm::ProcessSubprogramAttachment(const Function &F,
+                                                CloneFunctionChangeType Changes,
+                                                DebugInfoFinder &DIFinder) {
+  DISubprogram *SPClonedWithinModule = nullptr;
+  if (Changes < CloneFunctionChangeType::DifferentModule) {
+    SPClonedWithinModule = F.getSubprogram();
+  }
+  if (SPClonedWithinModule)
+    DIFinder.processSubprogram(SPClonedWithinModule);
+
+  const Module *M = F.getParent();
+  if (Changes != CloneFunctionChangeType::ClonedModule && M) {
+    // Inspect instructions to process e.g. DILexicalBlocks of inlined functions
+    for (const auto &BB : F) {
+      for (const auto &I : BB) {
+        DIFinder.processInstruction(*M, I);
+      }
----------------
felipepiovezan wrote:

```
for (const auto &I : instructions(F))
  DIFinder...
```

[No need to go over BBs](https://llvm.org/doxygen/InstIterator_8h.html), also [no braces in single-line blocks](https://llvm.org/docs/CodingStandards.html#don-t-use-braces-on-simple-single-statement-bodies-of-if-else-loop-statements)


https://github.com/llvm/llvm-project/pull/114537