[llvm] [llvm-profdata] Enabled functionality to write split-layout profile (PR #101795)

[Lei Wang via llvm-commits]

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@@ -223,6 +223,11 @@ static bool ParseLine(const StringRef &Input, LineType &LineTy, uint32_t &Depth,
 
   if (Input[Depth] == '!') {
     LineTy = LineType::Metadata;
+    // This metadata is only for manual inspection only. We already created a
+    // FunctionSamples and put it in the profile map, so there is no point
+    // to skip profiles even they have no use for ThinLTO.
+    if (Input == StringRef(" !Flat"))
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wlei-llvm wrote:

Makes sense, thanks for the clarification. I thought for other incompatible cases( Profile Symbol List, PartialProfile, ProfileIsFS, etc), mostly because they don't support text format, but here as the text format is added, so maybe it's not hard to support the compatibility. 

https://github.com/llvm/llvm-project/pull/101795