[llvm] [NVPTX] instcombine known pointer AS checks. (PR #112964)

[Alex MacLean via llvm-commits]

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@@ -413,11 +416,65 @@ static Instruction *simplifyNvvmIntrinsic(IntrinsicInst *II, InstCombiner &IC) {
   llvm_unreachable("All SpecialCase enumerators should be handled in switch.");
 }
 
+// Returns an instruction pointer (may be nullptr if we do not know the answer).
+// Returns nullopt if `II` is not one of the `isspacep` intrinsics.
+static std::optional<Instruction *>
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AlexMaclean wrote:

Fair enough.

https://github.com/llvm/llvm-project/pull/112964