[Lldb-commits] [PATCH] D123281: [trace][intel pt] Create a common accessor for live and postmortem data

[walter erquinigo via Phabricator via lldb-commits]

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Some parts of the code have to distinguish between live and postmortem threads
to figure out how to get some data, e.g. thread trace buffers. This makes the
code less generic and more error prone. An example of that is that we have
two different decoders: LiveThreadDecoder and PostMortemThreadDecoder. They
exist because getting the trace bufer is different for each case.

The problem doesn't stop there. Soon we'll have even more kinds of data, like
the context switch trace, whose fetching will be different for live and post-
mortem processes.

As a way to fix this, I'm creating a common API for accessing thread data,
which is able to figure out how to handle the postmortem and live cases on
behalf of the caller. As a result of that, I was able to eliminate the two
decoders and unify them into a simpler one. Not only that, our TraceSave
functionality only worked for live threads, but now it can also work for
postmortem processes, which might be useful now, but it might in the future.

This common API is OnThreadBinaryDataRead. More information in the inline 
documentation.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D123281

Files:
  lldb/include/lldb/Target/Trace.h
  lldb/source/Plugins/Trace/common/TraceSessionSaver.cpp
  lldb/source/Plugins/Trace/common/TraceSessionSaver.h
  lldb/source/Plugins/Trace/intel-pt/LibiptDecoder.cpp
  lldb/source/Plugins/Trace/intel-pt/ThreadDecoder.cpp
  lldb/source/Plugins/Trace/intel-pt/ThreadDecoder.h
  lldb/source/Plugins/Trace/intel-pt/TraceIntelPT.cpp
  lldb/source/Plugins/Trace/intel-pt/TraceIntelPT.h
  lldb/source/Plugins/Trace/intel-pt/TraceIntelPTSessionSaver.cpp
  lldb/source/Target/Trace.cpp

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