[llvm] [SPIR-V] Diagnose function used as data pointer without SPV_INTEL_function_pointers (PR #207347)

[Arseniy Obolenskiy via llvm-commits]

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@@ -258,7 +258,9 @@ static void insertBitcasts(MachineFunction &MF, SPIRVGlobalRegistry *GR,
       Register Source = MI.getOperand(2).getReg();
       Type *ElemTy = getMDOperandAsType(MI.getOperand(3).getMetadata(), 0);
       auto SC =
-          isa<FunctionType>(ElemTy)
+          isa<FunctionType>(ElemTy) &&
+                  ST->canUseExtension(
+                      SPIRV::Extension::SPV_INTEL_function_pointers)
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aobolensk wrote:

Done, added test with +SPV_INTEL_function_pointers (pass) and without (failed with an error)

https://github.com/llvm/llvm-project/pull/207347