[llvm] [DebugInfo] Add fast path for parsing DW_TAG_compile_unit abbrevs (PR #108757)

[Alex Langford via llvm-commits]

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@@ -1051,6 +1051,17 @@ DWARFUnit::getLastChildEntry(const DWARFDebugInfoEntry *Die) const {
   return nullptr;
 }
 
+const DWARFAbbreviationDeclaration *DWARFUnit::tryExtractCUAbbrevFast() const {
+  Expected<const DWARFAbbreviationDeclaration *> AbbrevOrError =
+      Abbrev->tryExtractCUAbbrevFast(getAbbreviationsOffset());
+  if (!AbbrevOrError) {
+    // FIXME: We should propagate this error upwards.
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bulbazord wrote:

Why not have this return an `Expected` as well? You added this function so you get to decide how its used, no?

https://github.com/llvm/llvm-project/pull/108757