[llvm] [DataLayout] Privatize and rename '*AlignElem' structs and enum (NFC) (PR #103723)

[Sergei Barannikov via llvm-commits]

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@@ -159,16 +154,25 @@ class DataLayout {
   /// well-defined bitwise representation.
   SmallVector<unsigned, 8> NonIntegralAddressSpaces;
 
-  /// Attempts to set the alignment of the given type. Returns an error
-  /// description on failure.
-  Error setAlignment(AlignTypeEnum AlignType, Align ABIAlign, Align PrefAlign,
-                     uint32_t BitWidth);
+  // Searches for a primitive specification that matches the given bit width.
+  // Returns the end iterator if the specification is not found.
+  SmallVectorImpl<PrimitiveSpec>::const_iterator
+  getPrimitiveSpec(const SmallVectorImpl<PrimitiveSpec> &Specs,
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s-barannikov wrote:

This declaration is also unnecessary if the nested structs are public.

https://github.com/llvm/llvm-project/pull/103723