[clang] [llvm] [clang][SPIR-V] Implement -fspv-preserve-interface (PR #196404)

[Juan Manuel Martinez Caamaño via cfe-commits]

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@@ -2507,7 +2542,7 @@ void SPIRVEmitIntrinsics::processGlobalValue(GlobalVariable &GV,
                                        {GV.getType(), Ty}, {&GV, Const});
     InitInst->setArgOperand(1, InitOp);
   }
-  if (!Init && GV.use_empty())
+  if (!Init && (GV.use_empty() || hasOnlyArtificialUses(GV)))
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jmmartinez wrote:

MC: `GV.use_empty()` implies `hasOnlyArtificialUses(GV)`; so it is redundant.

https://github.com/llvm/llvm-project/pull/196404