[llvm] RFC: [TTI] Assume casts between aliasing addrspaces are valid. NFCI. (PR #137969)

[Nikita Popov via llvm-commits]

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@@ -387,10 +387,6 @@ class BasicTTIImplBase : public TargetTransformInfoImplCRTPBase<T> {
 
   bool isAlwaysUniform(const Value *V) const override { return false; }
 
-  bool isValidAddrSpaceCast(unsigned FromAS, unsigned ToAS) const override {
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nikic wrote:

Probably anything that doesn't make use of TM/TLI (like this and surrounding methods) should only be in TTIImplBase rather than BasicTTIImpl?

https://github.com/llvm/llvm-project/pull/137969