[llvm] [ValueTracking] NFC: Allow tracking values through AddrSpaceCasts (PR #70483)

[Matt Arsenault via llvm-commits]

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@@ -895,6 +897,13 @@ class TargetTransformInfoImplBase {
 
   unsigned getMaxNumArgs() const { return UINT_MAX; }
 
+  std::optional<KnownBits>
+  computeKnownBitsAddrSpaceCast(unsigned DestAS, unsigned SrcAS,
+                                const APInt &DemandedElts, KnownBits &Known,
+                                const SimplifyQuery &Q) const {
+    return std::nullopt;
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arsenm wrote:

The default implementation might consider checking the alignment for integral address spaces 

https://github.com/llvm/llvm-project/pull/70483