contrib/llvm/lib/CodeGen/MachineOptimizationRemarkEmitter.cpp

   1 ///===- MachineOptimizationRemarkEmitter.cpp - Opt Diagnostic -*- 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 /// Optimization diagnostic interfaces for machine passes.  It's packaged as an
  11 /// analysis pass so that by using this service passes become dependent on MBFI
  12 /// as well.  MBFI is used to compute the "hotness" of the diagnostic message.
  13 ///
  14 ///===---------------------------------------------------------------------===//
  15
  16 #include "llvm/CodeGen/MachineOptimizationRemarkEmitter.h"
  17 #include "llvm/CodeGen/LazyMachineBlockFrequencyInfo.h"
  18 #include "llvm/CodeGen/MachineInstr.h"
  19 #include "llvm/IR/DebugInfo.h"
  20 #include "llvm/IR/DiagnosticInfo.h"
  21 #include "llvm/IR/LLVMContext.h"
  22
  23 using namespace llvm;
  24
  25 DiagnosticInfoMIROptimization::MachineArgument::MachineArgument(
  26     StringRef MKey, const MachineInstr &MI)
  27     : Argument() {
  28   Key = MKey;
  29
  30   raw_string_ostream OS(Val);
  31   MI.print(OS, /*SkipOpers=*/false, /*SkipDebugLoc=*/true);
  32 }
  33
  34 Optional<uint64_t>
  35 MachineOptimizationRemarkEmitter::computeHotness(const MachineBasicBlock &MBB) {
  36   if (!MBFI)
  37     return None;
  38
  39   return MBFI->getBlockProfileCount(&MBB);
  40 }
  41
  42 void MachineOptimizationRemarkEmitter::computeHotness(
  43     DiagnosticInfoMIROptimization &Remark) {
  44   const MachineBasicBlock *MBB = Remark.getBlock();
  45   if (MBB)
  46     Remark.setHotness(computeHotness(*MBB));
  47 }
  48
  49 void MachineOptimizationRemarkEmitter::emit(
  50     DiagnosticInfoOptimizationBase &OptDiagCommon) {
  51   auto &OptDiag = cast<DiagnosticInfoMIROptimization>(OptDiagCommon);
  52   computeHotness(OptDiag);
  53
  54   LLVMContext &Ctx = MF.getFunction()->getContext();
  55
  56   // If a diagnostic has a hotness value, then only emit it if its hotness
  57   // meets the threshold.
  58   if (OptDiag.getHotness() &&
  59       *OptDiag.getHotness() < Ctx.getDiagnosticsHotnessThreshold()) {
  60     return;
  61   }
  62
  63   yaml::Output *Out = Ctx.getDiagnosticsOutputFile();
  64   if (Out) {
  65     auto *P = &const_cast<DiagnosticInfoOptimizationBase &>(OptDiagCommon);
  66     *Out << P;
  67   }
  68   // FIXME: now that IsVerbose is part of DI, filtering for this will be moved
  69   // from here to clang.
  70   if (!OptDiag.isVerbose() || shouldEmitVerbose())
  71     Ctx.diagnose(OptDiag);
  72 }
  73
  74 MachineOptimizationRemarkEmitterPass::MachineOptimizationRemarkEmitterPass()
  75     : MachineFunctionPass(ID) {
  76   initializeMachineOptimizationRemarkEmitterPassPass(
  77       *PassRegistry::getPassRegistry());
  78 }
  79
  80 bool MachineOptimizationRemarkEmitterPass::runOnMachineFunction(
  81     MachineFunction &MF) {
  82   MachineBlockFrequencyInfo *MBFI;
  83
  84   if (MF.getFunction()->getContext().getDiagnosticsHotnessRequested())
  85     MBFI = &getAnalysis<LazyMachineBlockFrequencyInfoPass>().getBFI();
  86   else
  87     MBFI = nullptr;
  88
  89   ORE = llvm::make_unique<MachineOptimizationRemarkEmitter>(MF, MBFI);
  90   return false;
  91 }
  92
  93 void MachineOptimizationRemarkEmitterPass::getAnalysisUsage(
  94     AnalysisUsage &AU) const {
  95   AU.addRequired<LazyMachineBlockFrequencyInfoPass>();
  96   AU.setPreservesAll();
  97   MachineFunctionPass::getAnalysisUsage(AU);
  98 }
  99
 100 char MachineOptimizationRemarkEmitterPass::ID = 0;
 101 static const char ore_name[] = "Machine Optimization Remark Emitter";
 102 #define ORE_NAME "machine-opt-remark-emitter"
 103
 104 INITIALIZE_PASS_BEGIN(MachineOptimizationRemarkEmitterPass, ORE_NAME, ore_name,
 105                       false, true)
 106 INITIALIZE_PASS_DEPENDENCY(LazyMachineBlockFrequencyInfoPass)
 107 INITIALIZE_PASS_END(MachineOptimizationRemarkEmitterPass, ORE_NAME, ore_name,
 108                     false, true)