xref: /freebsd/contrib/llvm-project/llvm/lib/IR/ProfileSummary.cpp (revision 77013d11e6483b970af25e13c9b892075742f7e5)
1 //=-- Profilesummary.cpp - Profile summary support --------------------------=//
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 support for converting profile summary data from/to
10 // metadata.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "llvm/IR/ProfileSummary.h"
15 #include "llvm/IR/Attributes.h"
16 #include "llvm/IR/Constants.h"
17 #include "llvm/IR/Function.h"
18 #include "llvm/IR/Metadata.h"
19 #include "llvm/IR/Type.h"
20 #include "llvm/Support/Casting.h"
21 #include "llvm/Support/Format.h"
22 
23 using namespace llvm;
24 
25 // Return an MDTuple with two elements. The first element is a string Key and
26 // the second is a uint64_t Value.
27 static Metadata *getKeyValMD(LLVMContext &Context, const char *Key,
28                              uint64_t Val) {
29   Type *Int64Ty = Type::getInt64Ty(Context);
30   Metadata *Ops[2] = {MDString::get(Context, Key),
31                       ConstantAsMetadata::get(ConstantInt::get(Int64Ty, Val))};
32   return MDTuple::get(Context, Ops);
33 }
34 
35 static Metadata *getKeyFPValMD(LLVMContext &Context, const char *Key,
36                                double Val) {
37   Type *DoubleTy = Type::getDoubleTy(Context);
38   Metadata *Ops[2] = {MDString::get(Context, Key),
39                       ConstantAsMetadata::get(ConstantFP::get(DoubleTy, Val))};
40   return MDTuple::get(Context, Ops);
41 }
42 
43 // Return an MDTuple with two elements. The first element is a string Key and
44 // the second is a string Value.
45 static Metadata *getKeyValMD(LLVMContext &Context, const char *Key,
46                              const char *Val) {
47   Metadata *Ops[2] = {MDString::get(Context, Key), MDString::get(Context, Val)};
48   return MDTuple::get(Context, Ops);
49 }
50 
51 // This returns an MDTuple representing the detiled summary. The tuple has two
52 // elements: a string "DetailedSummary" and an MDTuple representing the value
53 // of the detailed summary. Each element of this tuple is again an MDTuple whose
54 // elements are the (Cutoff, MinCount, NumCounts) triplet of the
55 // DetailedSummaryEntry.
56 Metadata *ProfileSummary::getDetailedSummaryMD(LLVMContext &Context) {
57   std::vector<Metadata *> Entries;
58   Type *Int32Ty = Type::getInt32Ty(Context);
59   Type *Int64Ty = Type::getInt64Ty(Context);
60   for (auto &Entry : DetailedSummary) {
61     Metadata *EntryMD[3] = {
62         ConstantAsMetadata::get(ConstantInt::get(Int32Ty, Entry.Cutoff)),
63         ConstantAsMetadata::get(ConstantInt::get(Int64Ty, Entry.MinCount)),
64         ConstantAsMetadata::get(ConstantInt::get(Int32Ty, Entry.NumCounts))};
65     Entries.push_back(MDTuple::get(Context, EntryMD));
66   }
67   Metadata *Ops[2] = {MDString::get(Context, "DetailedSummary"),
68                       MDTuple::get(Context, Entries)};
69   return MDTuple::get(Context, Ops);
70 }
71 
72 // This returns an MDTuple representing this ProfileSummary object. The first
73 // entry of this tuple is another MDTuple of two elements: a string
74 // "ProfileFormat" and a string representing the format ("InstrProf" or
75 // "SampleProfile"). The rest of the elements of the outer MDTuple are specific
76 // to the kind of profile summary as returned by getFormatSpecificMD.
77 // IsPartialProfile is an optional field and \p AddPartialField will decide
78 // whether to add a field for it.
79 // PartialProfileRatio is an optional field and \p AddPartialProfileRatioField
80 // will decide whether to add a field for it.
81 Metadata *ProfileSummary::getMD(LLVMContext &Context, bool AddPartialField,
82                                 bool AddPartialProfileRatioField) {
83   const char *KindStr[3] = {"InstrProf", "CSInstrProf", "SampleProfile"};
84   SmallVector<Metadata *, 16> Components;
85   Components.push_back(getKeyValMD(Context, "ProfileFormat", KindStr[PSK]));
86   Components.push_back(getKeyValMD(Context, "TotalCount", getTotalCount()));
87   Components.push_back(getKeyValMD(Context, "MaxCount", getMaxCount()));
88   Components.push_back(
89       getKeyValMD(Context, "MaxInternalCount", getMaxInternalCount()));
90   Components.push_back(
91       getKeyValMD(Context, "MaxFunctionCount", getMaxFunctionCount()));
92   Components.push_back(getKeyValMD(Context, "NumCounts", getNumCounts()));
93   Components.push_back(getKeyValMD(Context, "NumFunctions", getNumFunctions()));
94   if (AddPartialField)
95     Components.push_back(
96         getKeyValMD(Context, "IsPartialProfile", isPartialProfile()));
97   if (AddPartialProfileRatioField)
98     Components.push_back(getKeyFPValMD(Context, "PartialProfileRatio",
99                                        getPartialProfileRatio()));
100   Components.push_back(getDetailedSummaryMD(Context));
101   return MDTuple::get(Context, Components);
102 }
103 
104 // Get the value metadata for the input MD/Key.
105 static ConstantAsMetadata *getValMD(MDTuple *MD, const char *Key) {
106   if (!MD)
107     return nullptr;
108   if (MD->getNumOperands() != 2)
109     return nullptr;
110   MDString *KeyMD = dyn_cast<MDString>(MD->getOperand(0));
111   ConstantAsMetadata *ValMD = dyn_cast<ConstantAsMetadata>(MD->getOperand(1));
112   if (!KeyMD || !ValMD)
113     return nullptr;
114   if (!KeyMD->getString().equals(Key))
115     return nullptr;
116   return ValMD;
117 }
118 
119 // Parse an MDTuple representing (Key, Val) pair.
120 static bool getVal(MDTuple *MD, const char *Key, uint64_t &Val) {
121   if (auto *ValMD = getValMD(MD, Key)) {
122     Val = cast<ConstantInt>(ValMD->getValue())->getZExtValue();
123     return true;
124   }
125   return false;
126 }
127 
128 static bool getVal(MDTuple *MD, const char *Key, double &Val) {
129   if (auto *ValMD = getValMD(MD, Key)) {
130     Val = cast<ConstantFP>(ValMD->getValue())->getValueAPF().convertToDouble();
131     return true;
132   }
133   return false;
134 }
135 
136 // Check if an MDTuple represents a (Key, Val) pair.
137 static bool isKeyValuePair(MDTuple *MD, const char *Key, const char *Val) {
138   if (!MD || MD->getNumOperands() != 2)
139     return false;
140   MDString *KeyMD = dyn_cast<MDString>(MD->getOperand(0));
141   MDString *ValMD = dyn_cast<MDString>(MD->getOperand(1));
142   if (!KeyMD || !ValMD)
143     return false;
144   if (!KeyMD->getString().equals(Key) || !ValMD->getString().equals(Val))
145     return false;
146   return true;
147 }
148 
149 // Parse an MDTuple representing detailed summary.
150 static bool getSummaryFromMD(MDTuple *MD, SummaryEntryVector &Summary) {
151   if (!MD || MD->getNumOperands() != 2)
152     return false;
153   MDString *KeyMD = dyn_cast<MDString>(MD->getOperand(0));
154   if (!KeyMD || !KeyMD->getString().equals("DetailedSummary"))
155     return false;
156   MDTuple *EntriesMD = dyn_cast<MDTuple>(MD->getOperand(1));
157   if (!EntriesMD)
158     return false;
159   for (auto &&MDOp : EntriesMD->operands()) {
160     MDTuple *EntryMD = dyn_cast<MDTuple>(MDOp);
161     if (!EntryMD || EntryMD->getNumOperands() != 3)
162       return false;
163     ConstantAsMetadata *Op0 =
164         dyn_cast<ConstantAsMetadata>(EntryMD->getOperand(0));
165     ConstantAsMetadata *Op1 =
166         dyn_cast<ConstantAsMetadata>(EntryMD->getOperand(1));
167     ConstantAsMetadata *Op2 =
168         dyn_cast<ConstantAsMetadata>(EntryMD->getOperand(2));
169 
170     if (!Op0 || !Op1 || !Op2)
171       return false;
172     Summary.emplace_back(cast<ConstantInt>(Op0->getValue())->getZExtValue(),
173                          cast<ConstantInt>(Op1->getValue())->getZExtValue(),
174                          cast<ConstantInt>(Op2->getValue())->getZExtValue());
175   }
176   return true;
177 }
178 
179 // Get the value of an optional field. Increment 'Idx' if it was present. Return
180 // true if we can move onto the next field.
181 template <typename ValueType>
182 static bool getOptionalVal(MDTuple *Tuple, unsigned &Idx, const char *Key,
183                            ValueType &Value) {
184   if (getVal(dyn_cast<MDTuple>(Tuple->getOperand(Idx)), Key, Value)) {
185     Idx++;
186     // Need to make sure when the key is present, we won't step over the bound
187     // of Tuple operand array. Since (non-optional) DetailedSummary always comes
188     // last, the next entry in the tuple operand array must exist.
189     return Idx < Tuple->getNumOperands();
190   }
191   // It was absent, keep going.
192   return true;
193 }
194 
195 ProfileSummary *ProfileSummary::getFromMD(Metadata *MD) {
196   MDTuple *Tuple = dyn_cast_or_null<MDTuple>(MD);
197   if (!Tuple || Tuple->getNumOperands() < 8 || Tuple->getNumOperands() > 10)
198     return nullptr;
199 
200   unsigned I = 0;
201   auto &FormatMD = Tuple->getOperand(I++);
202   ProfileSummary::Kind SummaryKind;
203   if (isKeyValuePair(dyn_cast_or_null<MDTuple>(FormatMD), "ProfileFormat",
204                      "SampleProfile"))
205     SummaryKind = PSK_Sample;
206   else if (isKeyValuePair(dyn_cast_or_null<MDTuple>(FormatMD), "ProfileFormat",
207                           "InstrProf"))
208     SummaryKind = PSK_Instr;
209   else if (isKeyValuePair(dyn_cast_or_null<MDTuple>(FormatMD), "ProfileFormat",
210                           "CSInstrProf"))
211     SummaryKind = PSK_CSInstr;
212   else
213     return nullptr;
214 
215   uint64_t NumCounts, TotalCount, NumFunctions, MaxFunctionCount, MaxCount,
216       MaxInternalCount;
217   if (!getVal(dyn_cast<MDTuple>(Tuple->getOperand(I++)), "TotalCount",
218               TotalCount))
219     return nullptr;
220   if (!getVal(dyn_cast<MDTuple>(Tuple->getOperand(I++)), "MaxCount", MaxCount))
221     return nullptr;
222   if (!getVal(dyn_cast<MDTuple>(Tuple->getOperand(I++)), "MaxInternalCount",
223               MaxInternalCount))
224     return nullptr;
225   if (!getVal(dyn_cast<MDTuple>(Tuple->getOperand(I++)), "MaxFunctionCount",
226               MaxFunctionCount))
227     return nullptr;
228   if (!getVal(dyn_cast<MDTuple>(Tuple->getOperand(I++)), "NumCounts",
229               NumCounts))
230     return nullptr;
231   if (!getVal(dyn_cast<MDTuple>(Tuple->getOperand(I++)), "NumFunctions",
232               NumFunctions))
233     return nullptr;
234 
235   // Optional fields. Need to initialize because the fields are optional.
236   uint64_t IsPartialProfile = 0;
237   if (!getOptionalVal(Tuple, I, "IsPartialProfile", IsPartialProfile))
238     return nullptr;
239   double PartialProfileRatio = 0;
240   if (!getOptionalVal(Tuple, I, "PartialProfileRatio", PartialProfileRatio))
241     return nullptr;
242 
243   SummaryEntryVector Summary;
244   if (!getSummaryFromMD(dyn_cast<MDTuple>(Tuple->getOperand(I++)), Summary))
245     return nullptr;
246   return new ProfileSummary(SummaryKind, std::move(Summary), TotalCount,
247                             MaxCount, MaxInternalCount, MaxFunctionCount,
248                             NumCounts, NumFunctions, IsPartialProfile,
249                             PartialProfileRatio);
250 }
251 
252 void ProfileSummary::printSummary(raw_ostream &OS) {
253   OS << "Total functions: " << NumFunctions << "\n";
254   OS << "Maximum function count: " << MaxFunctionCount << "\n";
255   OS << "Maximum block count: " << MaxCount << "\n";
256   OS << "Total number of blocks: " << NumCounts << "\n";
257   OS << "Total count: " << TotalCount << "\n";
258 }
259 
260 void ProfileSummary::printDetailedSummary(raw_ostream &OS) {
261   OS << "Detailed summary:\n";
262   for (const auto &Entry : DetailedSummary) {
263     OS << Entry.NumCounts << " blocks with count >= " << Entry.MinCount
264        << " account for "
265        << format("%0.6g", (float)Entry.Cutoff / Scale * 100)
266        << " percentage of the total counts.\n";
267   }
268 }
269