include/llvm/IR/PassTimingInfo.h

   1 //===- PassTimingInfo.h - pass execution timing -----------------*- C++ -*-===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 /// \file
   9 ///
  10 /// This header defines classes/functions to handle pass execution timing
  11 /// information with interfaces for both pass managers.
  12 ///
  13 //===----------------------------------------------------------------------===//
  14
  15 #ifndef LLVM_IR_PASSTIMINGINFO_H
  16 #define LLVM_IR_PASSTIMINGINFO_H
  17
  18 #include "llvm/ADT/Any.h"
  19 #include "llvm/ADT/DenseMap.h"
  20 #include "llvm/ADT/StringMap.h"
  21 #include "llvm/ADT/StringRef.h"
  22 #include "llvm/Support/Timer.h"
  23 #include "llvm/Support/TypeName.h"
  24 #include <memory>
  25 namespace llvm {
  26
  27 class Pass;
  28 class PassInstrumentationCallbacks;
  29
  30 /// If -time-passes has been specified, report the timings immediately and then
  31 /// reset the timers to zero.
  32 void reportAndResetTimings();
  33
  34 /// Request the timer for this legacy-pass-manager's pass instance.
  35 Timer *getPassTimer(Pass *);
  36
  37 /// If the user specifies the -time-passes argument on an LLVM tool command line
  38 /// then the value of this boolean will be true, otherwise false.
  39 /// This is the storage for the -time-passes option.
  40 extern bool TimePassesIsEnabled;
  41
  42 /// This class implements -time-passes functionality for new pass manager.
  43 /// It provides the pass-instrumentation callbacks that measure the pass
  44 /// execution time. They collect timing info into individual timers as
  45 /// passes are being run. At the end of its life-time it prints the resulting
  46 /// timing report.
  47 class TimePassesHandler {
  48   /// Value of this type is capable of uniquely identifying pass invocations.
  49   /// It is a pair of string Pass-Identifier (which for now is common
  50   /// to all the instance of a given pass) + sequential invocation counter.
  51   using PassInvocationID = std::pair<StringRef, unsigned>;
  52
  53   /// A group of all pass-timing timers.
  54   TimerGroup TG;
  55
  56   /// Map of timers for pass invocations
  57   DenseMap<PassInvocationID, std::unique_ptr<Timer>> TimingData;
  58
  59   /// Map that counts invocations of passes, for use in UniqPassID construction.
  60   StringMap<unsigned> PassIDCountMap;
  61
  62   /// Stack of currently active timers.
  63   SmallVector<Timer *, 8> TimerStack;
  64
  65   bool Enabled;
  66
  67 public:
  68   TimePassesHandler(bool Enabled = TimePassesIsEnabled);
  69
  70   /// Destructor handles the print action if it has not been handled before.
  71   ~TimePassesHandler() {
  72     // First destroying the timers from TimingData, which deploys all their
  73     // collected data into the TG time group member, which later prints itself
  74     // when being destroyed.
  75     TimingData.clear();
  76   }
  77
  78   /// Prints out timing information and then resets the timers.
  79   void print();
  80
  81   // We intend this to be unique per-compilation, thus no copies.
  82   TimePassesHandler(const TimePassesHandler &) = delete;
  83   void operator=(const TimePassesHandler &) = delete;
  84
  85   void registerCallbacks(PassInstrumentationCallbacks &PIC);
  86
  87 private:
  88   /// Dumps information for running/triggered timers, useful for debugging
  89   LLVM_DUMP_METHOD void dump() const;
  90
  91   /// Returns the new timer for each new run of the pass.
  92   Timer &getPassTimer(StringRef PassID);
  93
  94   /// Returns the incremented counter for the next invocation of \p PassID.
  95   unsigned nextPassID(StringRef PassID) { return ++PassIDCountMap[PassID]; }
  96
  97   void startTimer(StringRef PassID);
  98   void stopTimer(StringRef PassID);
  99
 100   // Implementation of pass instrumentation callbacks.
 101   bool runBeforePass(StringRef PassID);
 102   void runAfterPass(StringRef PassID);
 103 };
 104
 105 } // namespace llvm
 106
 107 #endif