[llvm] [IR] llvm.reloc.none intrinsic for no-op symbol references (PR #147427)

[Matt Arsenault via llvm-commits]

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@@ -7757,6 +7757,20 @@ void SelectionDAGBuilder::visitIntrinsicCall(const CallInst &I,
     return;
   }
 
+  case Intrinsic::reloc_none: {
+    Metadata *MD = cast<MetadataAsValue>(I.getArgOperand(0))->getMetadata();
+    StringRef SymbolName = cast<MDString>(MD)->getString();
+    auto *M = const_cast<Module *>(I.getModule());
+    auto *RelocSymbol = cast<GlobalVariable>(
+        M->getOrInsertGlobal(SymbolName, StructType::create(M->getContext())));
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arsenm wrote:

You don't need a GlobalValue reference to emit the symbol name in the end. You just need to encode this as an ExternalSymbol operand instead. The comment that it's "for debug info" doesn't really matter 

https://github.com/llvm/llvm-project/pull/147427