LLVM  12.0.0git
ProfileSummary.cpp
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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),
32  return MDTuple::get(Context, Ops);
33 }
34 
36  double Val) {
37  Type *DoubleTy = Type::getDoubleTy(Context);
38  Metadata *Ops[2] = {MDString::get(Context, Key),
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",
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));
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 
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 
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 
261  OS << "Detailed summary:\n";
262  for (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 }
static MDTuple * get(LLVMContext &Context, ArrayRef< Metadata *> MDs)
Definition: Metadata.h:1139
LLVM_NODISCARD std::enable_if_t< !is_simple_type< Y >::value, typename cast_retty< X, const Y >::ret_type > dyn_cast(const Y &Val)
Definition: Casting.h:334
static Type * getDoubleTy(LLVMContext &C)
Definition: Type.cpp:175
LLVMContext & Context
ProfileSummary(Kind K, SummaryEntryVector DetailedSummary, uint64_t TotalCount, uint64_t MaxCount, uint64_t MaxInternalCount, uint64_t MaxFunctionCount, uint32_t NumCounts, uint32_t NumFunctions, bool Partial=false, double PartialProfileRatio=0)
This class represents lattice values for constants.
Definition: AllocatorList.h:23
static MDString * get(LLVMContext &Context, StringRef Str)
Definition: Metadata.cpp:453
This file contains the declarations for metadata subclasses.
format_object< Ts... > format(const char *Fmt, const Ts &... Vals)
These are helper functions used to produce formatted output.
Definition: Format.h:124
static bool isKeyValuePair(MDTuple *MD, const char *Key, const char *Val)
const MDOperand & getOperand(unsigned I) const
Definition: Metadata.h:1075
static IntegerType * getInt64Ty(LLVMContext &C)
Definition: Type.cpp:187
uint64_t getMaxInternalCount()
Tuple of metadata.
Definition: Metadata.h:1112
static bool getVal(MDTuple *MD, const char *Key, uint64_t &Val)
static const int Scale
This file contains the simple types necessary to represent the attributes associated with functions a...
static Metadata * getKeyFPValMD(LLVMContext &Context, const char *Key, double Val)
Key
PAL metadata keys.
static Metadata * getKeyValMD(LLVMContext &Context, const char *Key, uint64_t Val)
op_range operands() const
Definition: Metadata.h:1073
uint64_t getMaxFunctionCount()
static ConstantAsMetadata * get(Constant *C)
Definition: Metadata.h:410
StringRef getString() const
Definition: Metadata.cpp:463
void printSummary(raw_ostream &OS)
The instances of the Type class are immutable: once they are created, they are never changed...
Definition: Type.h:46
This is an important class for using LLVM in a threaded context.
Definition: LLVMContext.h:68
This file contains the declarations for the subclasses of Constant, which represent the different fla...
uint64_t getTotalCount()
Metadata * getMD(LLVMContext &Context, bool AddPartialField=true, bool AddPartialProfileRatioField=true)
Return summary information as metadata.
Constant * getValue() const
Definition: Metadata.h:418
This is a &#39;vector&#39; (really, a variable-sized array), optimized for the case when the array is small...
Definition: SmallVector.h:883
static Constant * get(Type *Ty, uint64_t V, bool isSigned=false)
If Ty is a vector type, return a Constant with a splat of the given value.
Definition: Constants.cpp:786
static Constant * get(Type *Ty, double V)
This returns a ConstantFP, or a vector containing a splat of a ConstantFP, for the specified value in...
Definition: Constants.cpp:851
static bool getSummaryFromMD(MDTuple *MD, SummaryEntryVector &Summary)
static ProfileSummary * getFromMD(Metadata *MD)
Construct profile summary from metdata.
static ConstantAsMetadata * getValMD(MDTuple *MD, const char *Key)
LLVM_NODISCARD bool equals(StringRef RHS) const
equals - Check for string equality, this is more efficient than compare() when the relative ordering ...
Definition: StringRef.h:190
double getPartialProfileRatio()
uint32_t getNumFunctions()
static IntegerType * getInt32Ty(LLVMContext &C)
Definition: Type.cpp:186
#define I(x, y, z)
Definition: MD5.cpp:59
void printDetailedSummary(raw_ostream &OS)
static bool getOptionalVal(MDTuple *Tuple, unsigned &Idx, const char *Key, ValueType &Value)
LLVM Value Representation.
Definition: Value.h:74
This class implements an extremely fast bulk output stream that can only output to a stream...
Definition: raw_ostream.h:46
A single uniqued string.
Definition: Metadata.h:602
std::vector< ProfileSummaryEntry > SummaryEntryVector
unsigned getNumOperands() const
Return number of MDNode operands.
Definition: Metadata.h:1081
Root of the metadata hierarchy.
Definition: Metadata.h:58
IntegerType * Int32Ty
A discriminated union of two or more pointer types, with the discriminator in the low bit of the poin...
Definition: PointerUnion.h:156