[llvm] [NFC][SPIRV] Move common SPIRV::LinkageType deduction code to a helper in SPIRVUtils (PR #164248)

[Juan Manuel Martinez Caamaño via llvm-commits]

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@@ -4350,23 +4350,16 @@ bool SPIRVInstructionSelector::selectGlobalValue(
   if (hasInitializer(GlobalVar) && !Init)
     return true;
 
-  bool HasLnkTy = !GV->hasInternalLinkage() && !GV->hasPrivateLinkage() &&
-                  !GV->hasHiddenVisibility();
-  SPIRV::LinkageType::LinkageType LnkType =
-      GV->isDeclarationForLinker()
-          ? SPIRV::LinkageType::Import
-          : (GV->hasLinkOnceODRLinkage() &&
-                     STI.canUseExtension(SPIRV::Extension::SPV_KHR_linkonce_odr)
-                 ? SPIRV::LinkageType::LinkOnceODR
-                 : SPIRV::LinkageType::Export);
+  std::optional<SPIRV::LinkageType::LinkageType> LnkType =
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jmmartinez wrote:

Thanks ! I've added const in the last commit.

https://github.com/llvm/llvm-project/pull/164248