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/DiagnosticInfo.h"
20 #include "llvm/IR/LLVMContext.h"
21
22 using namespace llvm;
23
MachineArgument(StringRef MKey,const MachineInstr & MI)24 DiagnosticInfoMIROptimization::MachineArgument::MachineArgument(
25 StringRef MKey, const MachineInstr &MI)
26 : Argument() {
27 Key = MKey;
28
29 raw_string_ostream OS(Val);
30 MI.print(OS, /*IsStandalone=*/true, /*SkipOpers=*/false,
31 /*SkipDebugLoc=*/true);
32 }
33
34 Optional<uint64_t>
computeHotness(const MachineBasicBlock & MBB)35 MachineOptimizationRemarkEmitter::computeHotness(const MachineBasicBlock &MBB) {
36 if (!MBFI)
37 return None;
38
39 return MBFI->getBlockProfileCount(&MBB);
40 }
41
computeHotness(DiagnosticInfoMIROptimization & Remark)42 void MachineOptimizationRemarkEmitter::computeHotness(
43 DiagnosticInfoMIROptimization &Remark) {
44 const MachineBasicBlock *MBB = Remark.getBlock();
45 if (MBB)
46 Remark.setHotness(computeHotness(*MBB));
47 }
48
emit(DiagnosticInfoOptimizationBase & OptDiagCommon)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 // Only emit it if its hotness meets the threshold.
57 if (OptDiag.getHotness().getValueOr(0) <
58 Ctx.getDiagnosticsHotnessThreshold()) {
59 return;
60 }
61
62 Ctx.diagnose(OptDiag);
63 }
64
MachineOptimizationRemarkEmitterPass()65 MachineOptimizationRemarkEmitterPass::MachineOptimizationRemarkEmitterPass()
66 : MachineFunctionPass(ID) {
67 initializeMachineOptimizationRemarkEmitterPassPass(
68 *PassRegistry::getPassRegistry());
69 }
70
runOnMachineFunction(MachineFunction & MF)71 bool MachineOptimizationRemarkEmitterPass::runOnMachineFunction(
72 MachineFunction &MF) {
73 MachineBlockFrequencyInfo *MBFI;
74
75 if (MF.getFunction().getContext().getDiagnosticsHotnessRequested())
76 MBFI = &getAnalysis<LazyMachineBlockFrequencyInfoPass>().getBFI();
77 else
78 MBFI = nullptr;
79
80 ORE = llvm::make_unique<MachineOptimizationRemarkEmitter>(MF, MBFI);
81 return false;
82 }
83
getAnalysisUsage(AnalysisUsage & AU) const84 void MachineOptimizationRemarkEmitterPass::getAnalysisUsage(
85 AnalysisUsage &AU) const {
86 AU.addRequired<LazyMachineBlockFrequencyInfoPass>();
87 AU.setPreservesAll();
88 MachineFunctionPass::getAnalysisUsage(AU);
89 }
90
91 char MachineOptimizationRemarkEmitterPass::ID = 0;
92 static const char ore_name[] = "Machine Optimization Remark Emitter";
93 #define ORE_NAME "machine-opt-remark-emitter"
94
95 INITIALIZE_PASS_BEGIN(MachineOptimizationRemarkEmitterPass, ORE_NAME, ore_name,
96 false, true)
97 INITIALIZE_PASS_DEPENDENCY(LazyMachineBlockFrequencyInfoPass)
98 INITIALIZE_PASS_END(MachineOptimizationRemarkEmitterPass, ORE_NAME, ore_name,
99 false, true)
100