MachineSizeOpts.cpp revision 360784 
1//===- MachineSizeOpts.cpp - code size optimization related code ----------===//
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//
9// This file contains some shared machine IR code size optimization related
10// code.
11//
12//===----------------------------------------------------------------------===//
13
14#include "llvm/CodeGen/MachineSizeOpts.h"
15#include "llvm/Analysis/ProfileSummaryInfo.h"
16#include "llvm/CodeGen/MachineBlockFrequencyInfo.h"
17
18using namespace llvm;
19
20extern cl::opt<bool> EnablePGSO;
21extern cl::opt<bool> PGSOLargeWorkingSetSizeOnly;
22extern cl::opt<bool> ForcePGSO;
23extern cl::opt<int> PgsoCutoffInstrProf;
24extern cl::opt<int> PgsoCutoffSampleProf;
25
26namespace machine_size_opts_detail {
27
28/// Like ProfileSummaryInfo::isColdBlock but for MachineBasicBlock.
29bool isColdBlock(const MachineBasicBlock *MBB,
30                 ProfileSummaryInfo *PSI,
31                 const MachineBlockFrequencyInfo *MBFI) {
32  auto Count = MBFI->getBlockProfileCount(MBB);
33  return Count && PSI->isColdCount(*Count);
34}
35
36/// Like ProfileSummaryInfo::isHotBlockNthPercentile but for MachineBasicBlock.
37static bool isHotBlockNthPercentile(int PercentileCutoff,
38                                    const MachineBasicBlock *MBB,
39                                    ProfileSummaryInfo *PSI,
40                                    const MachineBlockFrequencyInfo *MBFI) {
41  auto Count = MBFI->getBlockProfileCount(MBB);
42  return Count && PSI->isHotCountNthPercentile(PercentileCutoff, *Count);
43}
44
45/// Like ProfileSummaryInfo::isFunctionColdInCallGraph but for
46/// MachineFunction.
47bool isFunctionColdInCallGraph(
48    const MachineFunction *MF,
49    ProfileSummaryInfo *PSI,
50    const MachineBlockFrequencyInfo &MBFI) {
51  if (auto FunctionCount = MF->getFunction().getEntryCount())
52    if (!PSI->isColdCount(FunctionCount.getCount()))
53      return false;
54  for (const auto &MBB : *MF)
55    if (!isColdBlock(&MBB, PSI, &MBFI))
56      return false;
57  return true;
58}
59
60/// Like ProfileSummaryInfo::isFunctionHotInCallGraphNthPercentile but for
61/// MachineFunction.
62bool isFunctionHotInCallGraphNthPercentile(
63    int PercentileCutoff,
64    const MachineFunction *MF,
65    ProfileSummaryInfo *PSI,
66    const MachineBlockFrequencyInfo &MBFI) {
67  if (auto FunctionCount = MF->getFunction().getEntryCount())
68    if (PSI->isHotCountNthPercentile(PercentileCutoff,
69                                     FunctionCount.getCount()))
70      return true;
71  for (const auto &MBB : *MF)
72    if (isHotBlockNthPercentile(PercentileCutoff, &MBB, PSI, &MBFI))
73      return true;
74  return false;
75}
76} // namespace machine_size_opts_detail
77
78namespace {
79struct MachineBasicBlockBFIAdapter {
80  static bool isFunctionColdInCallGraph(const MachineFunction *MF,
81                                        ProfileSummaryInfo *PSI,
82                                        const MachineBlockFrequencyInfo &MBFI) {
83    return machine_size_opts_detail::isFunctionColdInCallGraph(MF, PSI, MBFI);
84  }
85  static bool isFunctionHotInCallGraphNthPercentile(
86      int CutOff,
87      const MachineFunction *MF,
88      ProfileSummaryInfo *PSI,
89      const MachineBlockFrequencyInfo &MBFI) {
90    return machine_size_opts_detail::isFunctionHotInCallGraphNthPercentile(
91        CutOff, MF, PSI, MBFI);
92  }
93  static bool isColdBlock(const MachineBasicBlock *MBB,
94                          ProfileSummaryInfo *PSI,
95                          const MachineBlockFrequencyInfo *MBFI) {
96    return machine_size_opts_detail::isColdBlock(MBB, PSI, MBFI);
97  }
98  static bool isHotBlockNthPercentile(int CutOff,
99                                      const MachineBasicBlock *MBB,
100                                      ProfileSummaryInfo *PSI,
101                                      const MachineBlockFrequencyInfo *MBFI) {
102    return machine_size_opts_detail::isHotBlockNthPercentile(
103        CutOff, MBB, PSI, MBFI);
104  }
105};
106} // end anonymous namespace
107
108bool llvm::shouldOptimizeForSize(const MachineFunction *MF,
109                                 ProfileSummaryInfo *PSI,
110                                 const MachineBlockFrequencyInfo *MBFI,
111                                 PGSOQueryType QueryType) {
112  return shouldFuncOptimizeForSizeImpl<MachineBasicBlockBFIAdapter>(
113      MF, PSI, MBFI, QueryType);
114}
115
116bool llvm::shouldOptimizeForSize(const MachineBasicBlock *MBB,
117                                 ProfileSummaryInfo *PSI,
118                                 const MachineBlockFrequencyInfo *MBFI,
119                                 PGSOQueryType QueryType) {
120  return shouldOptimizeForSizeImpl<MachineBasicBlockBFIAdapter>(
121      MBB, PSI, MBFI, QueryType);
122}
123