[PATCH] D57702: [SelectionDAGBuilder] Add restrictions to EmitFuncArgumentDbgValue

[Jeremy Morse via Phabricator via llvm-commits]

jmorse added a comment.

Looks great,



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Comment at: llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp:4997
+    // emit using ArgDbgValue. This might catch some situations when the
+    // dgg.value refers to an argument that isn't used in the entry block, so
+    // any CopyToReg node would be optimized out and the only way to express
----------------
Typo dgg -> dbg


================
Comment at: llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp:5025-5032
+    if (VariableIsFunctionInputArg) {
+      unsigned ArgNo = Arg->getArgNo();
+      if (ArgNo >= FuncInfo.DescribedArgs.size())
+        FuncInfo.DescribedArgs.resize(ArgNo + 1);
+      else if (!IsInPrologue && FuncInfo.DescribedArgs.test(ArgNo))
+        return false;
+      FuncInfo.DescribedArgs.set(ArgNo);
----------------
Will this work with Arguments that are referred to by multiple fragments? Perhaps it doesn't need to, however the two-i32s-packed-in-i64-argument in PR40188 sprung to mind as that produces two DBG_VALUEs based on one Argument.


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D57702/new/

https://reviews.llvm.org/D57702