[llvm] [SCEV] Introduce exact flag for UDiv (PR #225065)

[David Sherwood via llvm-commits]

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@@ -154,16 +155,14 @@ struct SCEVUseT : private PointerIntPair<SCEVPtrT, 2> {
   /// flags and the underlying SCEV's flags, masked by \p Mask.
   SCEVFlags getNoWrapFlags(SCEVFlags Mask = SCEVFlags::FlagsNoWrapMask) const;
 
+  /// Return the flags for this SCEVUse, masked for the exact flag.
+  SCEVFlags getExactFlag() const;
+
   /// Return only the use-specific flags without the underlying SCEV's flags.
   SCEVFlags getUseNoWrapFlags() const {
     return getUseFlags() & SCEVFlags::FlagsNoWrapMask;
   }
-  SCEVFlags getUseFlags() const {
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david-arm wrote:

Some of these changes like this could be done in a separate NFC PR to reduce the diff and make it easier to reason about the changes.

https://github.com/llvm/llvm-project/pull/225065