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

[Artem Belevich via llvm-commits]

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@@ -6365,6 +6367,34 @@ static Value *simplifyUnaryIntrinsic(Function *F, Value *Op0,
 
     break;
   }
+  case Intrinsic::nvvm_isspacep_global:
+  case Intrinsic::nvvm_isspacep_local:
+  case Intrinsic::nvvm_isspacep_shared:
+  case Intrinsic::nvvm_isspacep_const: {
+    auto *Ty = F->getReturnType();
+    unsigned AS = Op0->getType()->getPointerAddressSpace();
+    if (AS == NVPTXAS::ADDRESS_SPACE_GENERIC) {
+      if (auto *ASC = dyn_cast<AddrSpaceCastInst>(Op0))
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Artem-B wrote:

I think that's handled by the `ConstantExpr` below.

At least, that's what handles `ptr addrspacecast (ptr addrspace(3) @shared_data to ptr)` in the tests. 

I guess casting directly to `AddrSpaceCastOperator` would avoid explicit comparison of the opcode with `Instruction::AddrSpaceCast`.



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