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/BlockFrequencyInfo.h"
17 #include "llvm/Analysis/ProfileSummaryInfo.h"
18 #include "llvm/Support/CommandLine.h"
19 
20 extern llvm::cl::opt<bool> EnablePGSO;
21 extern llvm::cl::opt<bool> PGSOLargeWorkingSetSizeOnly;
22 extern llvm::cl::opt<bool> PGSOIRPassOrTestOnly;
23 extern llvm::cl::opt<bool> PGSOColdCodeOnly;
24 extern llvm::cl::opt<bool> ForcePGSO;
25 extern llvm::cl::opt<int> PgsoCutoffInstrProf;
26 extern llvm::cl::opt<int> PgsoCutoffSampleProf;
27 
28 namespace llvm {
29 
30 class BasicBlock;
31 class BlockFrequencyInfo;
32 class Function;
33 class ProfileSummaryInfo;
34 
35 enum class PGSOQueryType {
36   IRPass, // A query call from an IR-level transform pass.
37   Test,   // A query call from a unit test.
38   Other,  // Others.
39 };
40 
41 template<typename AdapterT, typename FuncT, typename BFIT>
42 bool shouldFuncOptimizeForSizeImpl(const FuncT *F, ProfileSummaryInfo *PSI,
43                                    BFIT *BFI, PGSOQueryType QueryType) {
44   assert(F);
45   if (!PSI || !BFI || !PSI->hasProfileSummary())
46     return false;
47   if (ForcePGSO)
48     return true;
49   if (!EnablePGSO)
50     return false;
51   // Temporarily enable size optimizations only for the IR pass or test query
52   // sites for gradual commit/rollout. This is to be removed later.
53   if (PGSOIRPassOrTestOnly && !(QueryType == PGSOQueryType::IRPass ||
54                                 QueryType == PGSOQueryType::Test))
55     return false;
56   if (PGSOColdCodeOnly ||
57       (PGSOLargeWorkingSetSizeOnly && !PSI->hasLargeWorkingSetSize())) {
58     // Even if the working set size isn't large, size-optimize cold code.
59     return AdapterT::isFunctionColdInCallGraph(F, PSI, *BFI);
60   }
61   return !AdapterT::isFunctionHotInCallGraphNthPercentile(
62       PSI->hasSampleProfile() ? PgsoCutoffSampleProf : PgsoCutoffInstrProf,
63       F, PSI, *BFI);
64 }
65 
66 template<typename AdapterT, typename BlockT, typename BFIT>
67 bool shouldOptimizeForSizeImpl(const BlockT *BB, ProfileSummaryInfo *PSI,
68                                BFIT *BFI, PGSOQueryType QueryType) {
69   assert(BB);
70   if (!PSI || !BFI || !PSI->hasProfileSummary())
71     return false;
72   if (ForcePGSO)
73     return true;
74   if (!EnablePGSO)
75     return false;
76   // Temporarily enable size optimizations only for the IR pass or test query
77   // sites for gradual commit/rollout. This is to be removed later.
78   if (PGSOIRPassOrTestOnly && !(QueryType == PGSOQueryType::IRPass ||
79                                 QueryType == PGSOQueryType::Test))
80     return false;
81   if (PGSOColdCodeOnly ||
82       (PGSOLargeWorkingSetSizeOnly && !PSI->hasLargeWorkingSetSize())) {
83     // Even if the working set size isn't large, size-optimize cold code.
84     return AdapterT::isColdBlock(BB, PSI, BFI);
85   }
86   return !AdapterT::isHotBlockNthPercentile(
87       PSI->hasSampleProfile() ? PgsoCutoffSampleProf : PgsoCutoffInstrProf,
88       BB, PSI, 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