tools/llvm-mca/Views/SchedulerStatistics.h

   1 //===--------------------- SchedulerStatistics.h ----------------*- C++ -*-===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 /// \file
  10 ///
  11 /// This file defines class SchedulerStatistics. Class SchedulerStatistics is a
  12 /// View that listens to instruction issue events in order to print general
  13 /// statistics related to the hardware schedulers.
  14 ///
  15 /// Example:
  16 /// ========
  17 ///
  18 /// Schedulers - number of cycles where we saw N instructions issued:
  19 /// [# issued], [# cycles]
  20 ///  0,          6  (2.9%)
  21 ///  1,          106  (50.7%)
  22 ///  2,          97  (46.4%)
  23 ///
  24 /// Scheduler's queue usage:
  25 /// [1] Resource name.
  26 /// [2] Average number of used buffer entries.
  27 /// [3] Maximum number of used buffer entries.
  28 /// [4] Total number of buffer entries.
  29 ///
  30 ///  [1]            [2]        [3]        [4]
  31 /// JALU01           0          0          20
  32 /// JFPU01           15         18         18
  33 /// JLSAGU           0          0          12
  34 //
  35 //===----------------------------------------------------------------------===//
  36
  37 #ifndef LLVM_TOOLS_LLVM_MCA_SCHEDULERSTATISTICS_H
  38 #define LLVM_TOOLS_LLVM_MCA_SCHEDULERSTATISTICS_H
  39
  40 #include "Views/View.h"
  41 #include "llvm/ADT/SmallVector.h"
  42 #include "llvm/MC/MCSubtargetInfo.h"
  43 #include <map>
  44
  45 namespace mca {
  46
  47 class SchedulerStatistics final : public View {
  48   const llvm::MCSchedModel &SM;
  49   unsigned NumIssued;
  50   unsigned NumCycles;
  51
  52   // Tracks the usage of a scheduler's queue.
  53   struct BufferUsage {
  54     unsigned SlotsInUse;
  55     unsigned MaxUsedSlots;
  56     uint64_t CumulativeNumUsedSlots;
  57   };
  58
  59   std::vector<unsigned> IssuedPerCycle;
  60   std::vector<BufferUsage> Usage;
  61
  62   void updateHistograms();
  63   void printSchedulerStats(llvm::raw_ostream &OS) const;
  64   void printSchedulerUsage(llvm::raw_ostream &OS) const;
  65
  66 public:
  67   SchedulerStatistics(const llvm::MCSubtargetInfo &STI)
  68       : SM(STI.getSchedModel()), NumIssued(0), NumCycles(0),
  69         IssuedPerCycle(STI.getSchedModel().NumProcResourceKinds, 0),
  70         Usage(STI.getSchedModel().NumProcResourceKinds, {0, 0, 0}) {}
  71
  72   void onEvent(const HWInstructionEvent &Event) override;
  73
  74   void onCycleBegin() override { NumCycles++; }
  75
  76   void onCycleEnd() override { updateHistograms(); }
  77
  78   // Increases the number of used scheduler queue slots of every buffered
  79   // resource in the Buffers set.
  80   void onReservedBuffers(const InstRef &IR,
  81                          llvm::ArrayRef<unsigned> Buffers) override;
  82
  83   // Decreases by one the number of used scheduler queue slots of every
  84   // buffered resource in the Buffers set.
  85   void onReleasedBuffers(const InstRef &IR,
  86                          llvm::ArrayRef<unsigned> Buffers) override;
  87
  88   void printView(llvm::raw_ostream &OS) const override;
  89 };
  90 } // namespace mca
  91
  92 #endif