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

[Sergei Barannikov 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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s-barannikov wrote:

`TTIImplBase` has two derived classes, `BasicTTIImpl` and `NoTTIImpl`. The latter is used when the target doesn't provide its own implementation of `TTIImplBase` (which is usually done by inheriting from `BasicTTIImpl`).


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