[llvm] [SelectionDAG] Preserve cache hint metadata during legalization (PR #225273)

[Matt Arsenault via llvm-commits]

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@@ -1493,6 +1493,13 @@ class MemSDNode : public SDNode {
     return getMemOperand()->getMemCacheHint();
   }
 
+  /// Returns LLVM IR metadata carried by this memory access, except for range
+  /// metadata. Range metadata describes a loaded value and cannot be blindly
+  /// transferred when an access is split or its type changes.
+  MMOMetadata getNonRangeMMOMetadata() const {
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arsenm wrote:

e.g., if we bothered to propagate nofpclass metadata would that be covered under range?

https://github.com/llvm/llvm-project/pull/225273