1 //=-- ProfilesummaryBuilder.cpp - Profile summary computation ---------------=//
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 //
10 // This file contains support for computing profile summary data.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "llvm/IR/Attributes.h"
15 #include "llvm/IR/Function.h"
16 #include "llvm/IR/Metadata.h"
17 #include "llvm/IR/Type.h"
18 #include "llvm/ProfileData/InstrProf.h"
19 #include "llvm/ProfileData/ProfileCommon.h"
20 #include "llvm/ProfileData/SampleProf.h"
21 #include "llvm/Support/Casting.h"
22 
23 using namespace llvm;
24 
25 // A set of cutoff values. Each value, when divided by ProfileSummary::Scale
26 // (which is 1000000) is a desired percentile of total counts.
27 static const uint32_t DefaultCutoffsData[] = {
28     10000,  /*  1% */
29     100000, /* 10% */
30     200000, 300000, 400000, 500000, 600000, 700000, 800000,
31     900000, 950000, 990000, 999000, 999900, 999990, 999999};
32 const ArrayRef<uint32_t> ProfileSummaryBuilder::DefaultCutoffs =
33     DefaultCutoffsData;
34 
35 void InstrProfSummaryBuilder::addRecord(const InstrProfRecord &R) {
36   // The first counter is not necessarily an entry count for IR
37   // instrumentation profiles.
38   // Eventually MaxFunctionCount will become obsolete and this can be
39   // removed.
40   addEntryCount(R.Counts[0]);
41   for (size_t I = 1, E = R.Counts.size(); I < E; ++I)
42     addInternalCount(R.Counts[I]);
43 }
44 
45 // To compute the detailed summary, we consider each line containing samples as
46 // equivalent to a block with a count in the instrumented profile.
47 void SampleProfileSummaryBuilder::addRecord(
48     const sampleprof::FunctionSamples &FS) {
49   NumFunctions++;
50   if (FS.getHeadSamples() > MaxFunctionCount)
51     MaxFunctionCount = FS.getHeadSamples();
52   for (const auto &I : FS.getBodySamples())
53     addCount(I.second.getSamples());
54 }
55 
56 // The argument to this method is a vector of cutoff percentages and the return
57 // value is a vector of (Cutoff, MinCount, NumCounts) triplets.
58 void ProfileSummaryBuilder::computeDetailedSummary() {
59   if (DetailedSummaryCutoffs.empty())
60     return;
61   llvm::sort(DetailedSummaryCutoffs);
62   auto Iter = CountFrequencies.begin();
63   const auto End = CountFrequencies.end();
64 
65   uint32_t CountsSeen = 0;
66   uint64_t CurrSum = 0, Count = 0;
67 
68   for (const uint32_t Cutoff : DetailedSummaryCutoffs) {
69     assert(Cutoff <= 999999);
70     APInt Temp(128, TotalCount);
71     APInt N(128, Cutoff);
72     APInt D(128, ProfileSummary::Scale);
73     Temp *= N;
74     Temp = Temp.sdiv(D);
75     uint64_t DesiredCount = Temp.getZExtValue();
76     assert(DesiredCount <= TotalCount);
77     while (CurrSum < DesiredCount && Iter != End) {
78       Count = Iter->first;
79       uint32_t Freq = Iter->second;
80       CurrSum += (Count * Freq);
81       CountsSeen += Freq;
82       Iter++;
83     }
84     assert(CurrSum >= DesiredCount);
85     ProfileSummaryEntry PSE = {Cutoff, Count, CountsSeen};
86     DetailedSummary.push_back(PSE);
87   }
88 }
89 
90 std::unique_ptr<ProfileSummary> SampleProfileSummaryBuilder::getSummary() {
91   computeDetailedSummary();
92   return llvm::make_unique<ProfileSummary>(
93       ProfileSummary::PSK_Sample, DetailedSummary, TotalCount, MaxCount, 0,
94       MaxFunctionCount, NumCounts, NumFunctions);
95 }
96 
97 std::unique_ptr<ProfileSummary> InstrProfSummaryBuilder::getSummary() {
98   computeDetailedSummary();
99   return llvm::make_unique<ProfileSummary>(
100       ProfileSummary::PSK_Instr, DetailedSummary, TotalCount, MaxCount,
101       MaxInternalBlockCount, MaxFunctionCount, NumCounts, NumFunctions);
102 }
103 
104 void InstrProfSummaryBuilder::addEntryCount(uint64_t Count) {
105   addCount(Count);
106   NumFunctions++;
107   if (Count > MaxFunctionCount)
108     MaxFunctionCount = Count;
109 }
110 
111 void InstrProfSummaryBuilder::addInternalCount(uint64_t Count) {
112   addCount(Count);
113   if (Count > MaxInternalBlockCount)
114     MaxInternalBlockCount = Count;
115 }
116