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/IR/DebugInfo.h"
19 #include "llvm/IR/DiagnosticInfo.h"
20 #include "llvm/IR/LLVMContext.h"
21 
22 using namespace llvm;
23 
24 Optional<uint64_t>
25 MachineOptimizationRemarkEmitter::computeHotness(const MachineBasicBlock &MBB) {
26   if (!MBFI)
27     return None;
28 
29   return MBFI->getBlockProfileCount(&MBB);
30 }
31 
32 void MachineOptimizationRemarkEmitter::computeHotness(
33     DiagnosticInfoMIROptimization &Remark) {
34   const MachineBasicBlock *MBB = Remark.getBlock();
35   if (MBB)
36     Remark.setHotness(computeHotness(*MBB));
37 }
38 
39 void MachineOptimizationRemarkEmitter::emit(
40     DiagnosticInfoOptimizationBase &OptDiagCommon) {
41   auto &OptDiag = cast<DiagnosticInfoMIROptimization>(OptDiagCommon);
42   computeHotness(OptDiag);
43 
44   LLVMContext &Ctx = MF.getFunction()->getContext();
45   yaml::Output *Out = Ctx.getDiagnosticsOutputFile();
46   if (Out) {
47     auto *P = &const_cast<DiagnosticInfoOptimizationBase &>(OptDiagCommon);
48     *Out << P;
49   }
50   // FIXME: now that IsVerbose is part of DI, filtering for this will be moved
51   // from here to clang.
52   if (!OptDiag.isVerbose() || shouldEmitVerbose())
53     Ctx.diagnose(OptDiag);
54 }
55 
56 MachineOptimizationRemarkEmitterPass::MachineOptimizationRemarkEmitterPass()
57     : MachineFunctionPass(ID) {
58   initializeMachineOptimizationRemarkEmitterPassPass(
59       *PassRegistry::getPassRegistry());
60 }
61 
62 bool MachineOptimizationRemarkEmitterPass::runOnMachineFunction(
63     MachineFunction &MF) {
64   MachineBlockFrequencyInfo *MBFI;
65 
66   if (MF.getFunction()->getContext().getDiagnosticHotnessRequested())
67     MBFI = &getAnalysis<LazyMachineBlockFrequencyInfoPass>().getBFI();
68   else
69     MBFI = nullptr;
70 
71   ORE = llvm::make_unique<MachineOptimizationRemarkEmitter>(MF, MBFI);
72   return false;
73 }
74 
75 void MachineOptimizationRemarkEmitterPass::getAnalysisUsage(
76     AnalysisUsage &AU) const {
77   LazyMachineBlockFrequencyInfoPass::getLazyMachineBFIAnalysisUsage(AU);
78   AU.setPreservesAll();
79   MachineFunctionPass::getAnalysisUsage(AU);
80 }
81 
82 char MachineOptimizationRemarkEmitterPass::ID = 0;
83 static const char ore_name[] = "Machine Optimization Remark Emitter";
84 #define ORE_NAME "machine-opt-remark-emitter"
85 
86 INITIALIZE_PASS_BEGIN(MachineOptimizationRemarkEmitterPass, ORE_NAME, ore_name,
87                       false, true)
88 INITIALIZE_PASS_DEPENDENCY(LazyMachineBFIPass)
89 INITIALIZE_PASS_END(MachineOptimizationRemarkEmitterPass, ORE_NAME, ore_name,
90                     false, true)
91