1 //===- llvm/Transforms/Utils/SizeOpts.h - size optimization -----*- 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 //
9 // This file contains some shared code size optimization related code.
10 //
11 //===----------------------------------------------------------------------===//
12
13 #ifndef LLVM_TRANSFORMS_UTILS_SIZEOPTS_H
14 #define LLVM_TRANSFORMS_UTILS_SIZEOPTS_H
15
16 #include "llvm/Analysis/ProfileSummaryInfo.h"
17 #include "llvm/Support/CommandLine.h"
18
19 namespace llvm {
20 extern cl::opt<bool> EnablePGSO;
21 extern cl::opt<bool> PGSOLargeWorkingSetSizeOnly;
22 extern cl::opt<bool> PGSOColdCodeOnly;
23 extern cl::opt<bool> PGSOColdCodeOnlyForInstrPGO;
24 extern cl::opt<bool> PGSOColdCodeOnlyForSamplePGO;
25 extern cl::opt<bool> PGSOColdCodeOnlyForPartialSamplePGO;
26 extern cl::opt<bool> ForcePGSO;
27 extern cl::opt<int> PgsoCutoffInstrProf;
28 extern cl::opt<int> PgsoCutoffSampleProf;
29
30 class BasicBlock;
31 class BlockFrequencyInfo;
32 class Function;
33
34 enum class PGSOQueryType {
35 IRPass, // A query call from an IR-level transform pass.
36 Test, // A query call from a unit test.
37 Other, // Others.
38 };
39
isPGSOColdCodeOnly(ProfileSummaryInfo * PSI)40 static inline bool isPGSOColdCodeOnly(ProfileSummaryInfo *PSI) {
41 return PGSOColdCodeOnly ||
42 (PSI->hasInstrumentationProfile() && PGSOColdCodeOnlyForInstrPGO) ||
43 (PSI->hasSampleProfile() &&
44 ((!PSI->hasPartialSampleProfile() && PGSOColdCodeOnlyForSamplePGO) ||
45 (PSI->hasPartialSampleProfile() &&
46 PGSOColdCodeOnlyForPartialSamplePGO))) ||
47 (PGSOLargeWorkingSetSizeOnly && !PSI->hasLargeWorkingSetSize());
48 }
49
50 template <typename FuncT, typename BFIT>
shouldFuncOptimizeForSizeImpl(const FuncT * F,ProfileSummaryInfo * PSI,BFIT * BFI,PGSOQueryType QueryType)51 bool shouldFuncOptimizeForSizeImpl(const FuncT *F, ProfileSummaryInfo *PSI,
52 BFIT *BFI, PGSOQueryType QueryType) {
53 assert(F);
54 if (!PSI || !BFI || !PSI->hasProfileSummary())
55 return false;
56 if (ForcePGSO)
57 return true;
58 if (!EnablePGSO)
59 return false;
60 if (isPGSOColdCodeOnly(PSI))
61 return PSI->isFunctionColdInCallGraph(F, *BFI);
62 if (PSI->hasSampleProfile())
63 // The "isCold" check seems to work better for Sample PGO as it could have
64 // many profile-unannotated functions.
65 return PSI->isFunctionColdInCallGraphNthPercentile(PgsoCutoffSampleProf, F,
66 *BFI);
67 return !PSI->isFunctionHotInCallGraphNthPercentile(PgsoCutoffInstrProf, F,
68 *BFI);
69 }
70
71 template <typename BlockTOrBlockFreq, typename BFIT>
shouldOptimizeForSizeImpl(BlockTOrBlockFreq BBOrBlockFreq,ProfileSummaryInfo * PSI,BFIT * BFI,PGSOQueryType QueryType)72 bool shouldOptimizeForSizeImpl(BlockTOrBlockFreq BBOrBlockFreq,
73 ProfileSummaryInfo *PSI, BFIT *BFI,
74 PGSOQueryType QueryType) {
75 if (!PSI || !BFI || !PSI->hasProfileSummary())
76 return false;
77 if (ForcePGSO)
78 return true;
79 if (!EnablePGSO)
80 return false;
81 if (isPGSOColdCodeOnly(PSI))
82 return PSI->isColdBlock(BBOrBlockFreq, BFI);
83 if (PSI->hasSampleProfile())
84 // The "isCold" check seems to work better for Sample PGO as it could have
85 // many profile-unannotated functions.
86 return PSI->isColdBlockNthPercentile(PgsoCutoffSampleProf, BBOrBlockFreq,
87 BFI);
88 return !PSI->isHotBlockNthPercentile(PgsoCutoffInstrProf, BBOrBlockFreq, BFI);
89 }
90
91 /// Returns true if function \p F is suggested to be size-optimized based on the
92 /// profile.
93 bool shouldOptimizeForSize(const Function *F, ProfileSummaryInfo *PSI,
94 BlockFrequencyInfo *BFI,
95 PGSOQueryType QueryType = PGSOQueryType::Other);
96
97 /// Returns true if basic block \p BB is suggested to be size-optimized based on
98 /// the profile.
99 bool shouldOptimizeForSize(const BasicBlock *BB, ProfileSummaryInfo *PSI,
100 BlockFrequencyInfo *BFI,
101 PGSOQueryType QueryType = PGSOQueryType::Other);
102
103 } // end namespace llvm
104
105 #endif // LLVM_TRANSFORMS_UTILS_SIZEOPTS_H
106