[PATCH] D41915: [lldCOFF] Print detailed timing information with /VERBOSE

[Rui Ueyama via Phabricator via llvm-commits]

ruiu added inline comments.


================
Comment at: lld/COFF/Driver.cpp:50
 
+static Timer InputFileTimer("Input File Reading");
+
----------------
Can you remove `addChildTimer` if you pass a parent timer to the constructor?


================
Comment at: lld/COFF/PDB.cpp:897
   }
+  U.stop();
 
----------------
I found T1, T2, ... (which you did in Writer.cpp) is better than T, U, V.


================
Comment at: lld/Common/Timer.cpp:8
+
+static bool IsTimingEnabled = false;
+
----------------
High resolution timer is very cheap on modern processors (I believe it is compiled to RSTSC instruction on x86, for example), so I think we should always enable this and just don't print out the final result if Config->ShowTiming is false.


================
Comment at: lld/Common/Timer.cpp:62
+  llvm::raw_svector_ostream Stream(Str);
+  repeat(Stream, '-', 49);
+  message(Str);
----------------
I believe this can be written without `repeat`:

  Stream << std::string('-', 49);


================
Comment at: lld/Common/Timer.cpp:80-87
+  int LI = Depth * 2;
+  int RI = std::max<int>(0, 30 - Name.size() - 1 - LI);
+  SmallString<32> Str;
+  llvm::raw_svector_ostream Stream(Str);
+  repeat(Stream, ' ', LI);
+  Stream << Name << ":";
+  repeat(Stream, ' ', RI);
----------------
  std::string S = (std::string(' ', Depth * 2) + Name).str();
  format("% 30s (%6.2f%%) %5d ms", S, 100 * millis() / TotalDuration, (int)millis());

is perhaps a bit easier to read?


================
Comment at: lld/include/lld/Common/Timer.h:35-41
+  std::chrono::time_point<std::chrono::high_resolution_clock> StartTime;
+  std::chrono::nanoseconds Total;
+  llvm::SmallVector<Timer *, 2> Children;
+  std::string Name;
+
+  void print(int Depth, double TotalDuration, bool Recurse = true) const;
+
----------------
We usually write private members after public members.


https://reviews.llvm.org/D41915