[llvm] [SPIRV] Handle `inttoptr` constant expressions in global initialisers (PR #166494)

[Alex Voicu via llvm-commits]

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@@ -348,6 +348,15 @@ static SPIRVType *propagateSPIRVType(MachineInstr *MI, SPIRVGlobalRegistry *GR,
         SpvType = GR->getOrCreateSPIRVIntegerType(
             MRI.getType(Reg).getScalarSizeInBits(), MIB);
         break;
+      case TargetOpcode::G_INTTOPTR:
+        // With opaque pointers it doesn't appear as if we can convert to
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AlexVlx wrote:

I don't think `assign.ptr.type` works for global values / quantities, as the assumption is that globals are already typeful. Hence the need to give this a type - in some sense it is symmetric with the `ptrtoint` above. There isn't enough context to infer any type other than `void*` at this point (these'd essentially be `ConstantExpr`s) - the only operator that'd carry extra type info might be GEP, but it's not immediately apparent how we'd have an `inttoptr` followed by `gep` sequence. Apologies if I misunderstood the gist of the question / suggestion or if I'm missing something obvious.

https://github.com/llvm/llvm-project/pull/166494