[PATCH] D55372: [DebugInfo] Emit "undef" DBG_VALUEs when SDNodes are optimised out

[Adrian Prantl via Phabricator via llvm-commits]

aprantl added a comment.

The basic idea looks good to me.



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Comment at: test/DebugInfo/X86/pieces-3.ll:40
   %outer.sroa.1.8.extract.trunc = trunc i64 %outer.coerce1 to i32, !dbg !33
   call void @llvm.dbg.value(metadata i32 %outer.sroa.1.8.extract.trunc, metadata !34, metadata !35), !dbg !33
   ret i32 %outer.sroa.1.8.extract.trunc, !dbg !36
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Why is this necessary?


Repository:
  rL LLVM

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D55372/new/

https://reviews.llvm.org/D55372