[llvm] [SPIR-V] Implement SPV_KHR_untyped_pointers extension (PR #201233)

[Juan Manuel Martinez Caamaño via llvm-commits]

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@@ -728,16 +731,19 @@ static bool buildAtomicCompareExchangeInst(
   SPIRVTypeInst SpvDesiredTy = GR->getSPIRVTypeForVReg(Desired);
   LLT DesiredLLT = MRI->getType(Desired);
 
-  assert(GR->getSPIRVTypeForVReg(ObjectPtr)->getOpcode() ==
-         SPIRV::OpTypePointer);
+  [[maybe_unused]] auto IsPtrTy = [](unsigned Op) {
+    return Op == SPIRV::OpTypePointer || Op == SPIRV::OpTypeUntypedPointerKHR;
+  };
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jmmartinez wrote:

Maybe we can move this as a helper in `SPIRVTypeInst.h`. The same check also appears in other assertions.

https://github.com/llvm/llvm-project/pull/201233