[llvm] [TTI][TLI] Expose TargetLowering::isOffsetFoldingLegal (backend) to TargetTransformInfo for middle-end cost-benefit analysis (PR #104644)

[Matt Arsenault via llvm-commits]

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@@ -665,6 +665,8 @@ class TargetTransformInfo {
   void getPeelingPreferences(Loop *L, ScalarEvolution &SE,
                              PeelingPreferences &PP) const;
 
+  bool isOffsetFoldingLegal(const GlobalValue *GV) const;
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arsenm wrote:

This still doesn't explain to me what "legal" means in this context. What offset? And for what value? 

https://github.com/llvm/llvm-project/pull/104644