[llvm] [ProfileData] Introduce SampleProfileFuncOffsetTable (NFC) (PR #205045)

[Kazu Hirata via llvm-commits]

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@@ -908,6 +908,79 @@ class FuncOffsetHashTableInfo {
   }
 };
 
+/// A unified wrapper representing the function offset table.
+///
+/// This class abstracts away the physical representation of the offset table,
+/// which can either be:
+///
+/// - An llvm::DenseMap mapping function GUIDs (or context hashes) to their
+///   profile offsets, populated when reading the array of offsets in
+///   context-sensitive (CS) profiles or version 103 profiles.
+///
+/// - An OnDiskIterableChainedHashTable providing the same mapping directly from
+///   the file in (non-context-sensitive) version 104 profiles.
+///
+/// It exposes a single, type-agnostic lookup interface, shielding the reader
+/// from the underlying container types. To prevent hybrid-state corruption, it
+/// enforces mutually exclusive paths using assertions.
+class SampleProfileFuncOffsetTable {
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kazutakahirata wrote:

Fixed in the latest revision.  Thanks!

https://github.com/llvm/llvm-project/pull/205045