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

[Juan Manuel Martinez Caamaño via llvm-commits]

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@@ -1210,8 +1210,16 @@ bool SPIRVInstructionSelector::selectUnOp(Register ResVReg,
     for (MachineRegisterInfo::def_instr_iterator DefIt =
              MRI->def_instr_begin(SrcReg);
          DefIt != MRI->def_instr_end(); DefIt = std::next(DefIt)) {
-      if ((*DefIt).getOpcode() == TargetOpcode::G_GLOBAL_VALUE ||
-          (*DefIt).getOpcode() == SPIRV::OpVariable) {
+      unsigned DefOpCode = (*DefIt).getOpcode();
+      if (DefOpCode == SPIRV::ASSIGN_TYPE) {
+        // We need special handling to look through the type assignment and see
+        // if this is a constant or a global
+        if (auto *VRD = getVRegDef(*MRI, (*DefIt).getOperand(1).getReg()))
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jmmartinez wrote:

Same NIT as above.
```suggestion
        if (auto *VRD = getVRegDef(*MRI, DefIt->getOperand(1).getReg()))
```

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