lib/IR/ProfileSummary.cpp

   1 //=-- Profilesummary.cpp - Profile summary support --------------------------=//
   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 converting profile summary data from/to
  11 // metadata.
  12 //
  13 //===----------------------------------------------------------------------===//
  14
  15 #include "llvm/IR/ProfileSummary.h"
  16 #include "llvm/IR/Attributes.h"
  17 #include "llvm/IR/Constants.h"
  18 #include "llvm/IR/Function.h"
  19 #include "llvm/IR/Metadata.h"
  20 #include "llvm/IR/Type.h"
  21 #include "llvm/Support/Casting.h"
  22
  23 using namespace llvm;
  24
  25 const char *ProfileSummary::KindStr[2] = {"InstrProf", "SampleProfile"};
  26
  27 // Return an MDTuple with two elements. The first element is a string Key and
  28 // the second is a uint64_t Value.
  29 static Metadata *getKeyValMD(LLVMContext &Context, const char *Key,
  30                              uint64_t Val) {
  31   Type *Int64Ty = Type::getInt64Ty(Context);
  32   Metadata *Ops[2] = {MDString::get(Context, Key),
  33                       ConstantAsMetadata::get(ConstantInt::get(Int64Ty, Val))};
  34   return MDTuple::get(Context, Ops);
  35 }
  36
  37 // Return an MDTuple with two elements. The first element is a string Key and
  38 // the second is a string Value.
  39 static Metadata *getKeyValMD(LLVMContext &Context, const char *Key,
  40                              const char *Val) {
  41   Metadata *Ops[2] = {MDString::get(Context, Key), MDString::get(Context, Val)};
  42   return MDTuple::get(Context, Ops);
  43 }
  44
  45 // This returns an MDTuple representing the detiled summary. The tuple has two
  46 // elements: a string "DetailedSummary" and an MDTuple representing the value
  47 // of the detailed summary. Each element of this tuple is again an MDTuple whose
  48 // elements are the (Cutoff, MinCount, NumCounts) triplet of the
  49 // DetailedSummaryEntry.
  50 Metadata *ProfileSummary::getDetailedSummaryMD(LLVMContext &Context) {
  51   std::vector<Metadata *> Entries;
  52   Type *Int32Ty = Type::getInt32Ty(Context);
  53   Type *Int64Ty = Type::getInt64Ty(Context);
  54   for (auto &Entry : DetailedSummary) {
  55     Metadata *EntryMD[3] = {
  56         ConstantAsMetadata::get(ConstantInt::get(Int32Ty, Entry.Cutoff)),
  57         ConstantAsMetadata::get(ConstantInt::get(Int64Ty, Entry.MinCount)),
  58         ConstantAsMetadata::get(ConstantInt::get(Int32Ty, Entry.NumCounts))};
  59     Entries.push_back(MDTuple::get(Context, EntryMD));
  60   }
  61   Metadata *Ops[2] = {MDString::get(Context, "DetailedSummary"),
  62                       MDTuple::get(Context, Entries)};
  63   return MDTuple::get(Context, Ops);
  64 }
  65
  66 // This returns an MDTuple representing this ProfileSummary object. The first
  67 // entry of this tuple is another MDTuple of two elements: a string
  68 // "ProfileFormat" and a string representing the format ("InstrProf" or
  69 // "SampleProfile"). The rest of the elements of the outer MDTuple are specific
  70 // to the kind of profile summary as returned by getFormatSpecificMD.
  71 Metadata *ProfileSummary::getMD(LLVMContext &Context) {
  72   Metadata *Components[] = {
  73     getKeyValMD(Context, "ProfileFormat", KindStr[PSK]),
  74     getKeyValMD(Context, "TotalCount", getTotalCount()),
  75     getKeyValMD(Context, "MaxCount", getMaxCount()),
  76     getKeyValMD(Context, "MaxInternalCount", getMaxInternalCount()),
  77     getKeyValMD(Context, "MaxFunctionCount", getMaxFunctionCount()),
  78     getKeyValMD(Context, "NumCounts", getNumCounts()),
  79     getKeyValMD(Context, "NumFunctions", getNumFunctions()),
  80     getDetailedSummaryMD(Context),
  81   };
  82   return MDTuple::get(Context, Components);
  83 }
  84
  85 // Parse an MDTuple representing (Key, Val) pair.
  86 static bool getVal(MDTuple *MD, const char *Key, uint64_t &Val) {
  87   if (!MD)
  88     return false;
  89   if (MD->getNumOperands() != 2)
  90     return false;
  91   MDString *KeyMD = dyn_cast<MDString>(MD->getOperand(0));
  92   ConstantAsMetadata *ValMD = dyn_cast<ConstantAsMetadata>(MD->getOperand(1));
  93   if (!KeyMD || !ValMD)
  94     return false;
  95   if (!KeyMD->getString().equals(Key))
  96     return false;
  97   Val = cast<ConstantInt>(ValMD->getValue())->getZExtValue();
  98   return true;
  99 }
 100
 101 // Check if an MDTuple represents a (Key, Val) pair.
 102 static bool isKeyValuePair(MDTuple *MD, const char *Key, const char *Val) {
 103   if (!MD || MD->getNumOperands() != 2)
 104     return false;
 105   MDString *KeyMD = dyn_cast<MDString>(MD->getOperand(0));
 106   MDString *ValMD = dyn_cast<MDString>(MD->getOperand(1));
 107   if (!KeyMD || !ValMD)
 108     return false;
 109   if (!KeyMD->getString().equals(Key) || !ValMD->getString().equals(Val))
 110     return false;
 111   return true;
 112 }
 113
 114 // Parse an MDTuple representing detailed summary.
 115 static bool getSummaryFromMD(MDTuple *MD, SummaryEntryVector &Summary) {
 116   if (!MD || MD->getNumOperands() != 2)
 117     return false;
 118   MDString *KeyMD = dyn_cast<MDString>(MD->getOperand(0));
 119   if (!KeyMD || !KeyMD->getString().equals("DetailedSummary"))
 120     return false;
 121   MDTuple *EntriesMD = dyn_cast<MDTuple>(MD->getOperand(1));
 122   if (!EntriesMD)
 123     return false;
 124   for (auto &&MDOp : EntriesMD->operands()) {
 125     MDTuple *EntryMD = dyn_cast<MDTuple>(MDOp);
 126     if (!EntryMD || EntryMD->getNumOperands() != 3)
 127       return false;
 128     ConstantAsMetadata *Op0 =
 129         dyn_cast<ConstantAsMetadata>(EntryMD->getOperand(0));
 130     ConstantAsMetadata *Op1 =
 131         dyn_cast<ConstantAsMetadata>(EntryMD->getOperand(1));
 132     ConstantAsMetadata *Op2 =
 133         dyn_cast<ConstantAsMetadata>(EntryMD->getOperand(2));
 134
 135     if (!Op0 || !Op1 || !Op2)
 136       return false;
 137     Summary.emplace_back(cast<ConstantInt>(Op0->getValue())->getZExtValue(),
 138                          cast<ConstantInt>(Op1->getValue())->getZExtValue(),
 139                          cast<ConstantInt>(Op2->getValue())->getZExtValue());
 140   }
 141   return true;
 142 }
 143
 144 ProfileSummary *ProfileSummary::getFromMD(Metadata *MD) {
 145   MDTuple *Tuple = dyn_cast_or_null<MDTuple>(MD);
 146   if (!Tuple || Tuple->getNumOperands() != 8)
 147     return nullptr;
 148
 149   auto &FormatMD = Tuple->getOperand(0);
 150   ProfileSummary::Kind SummaryKind;
 151   if (isKeyValuePair(dyn_cast_or_null<MDTuple>(FormatMD), "ProfileFormat",
 152                      "SampleProfile"))
 153     SummaryKind = PSK_Sample;
 154   else if (isKeyValuePair(dyn_cast_or_null<MDTuple>(FormatMD), "ProfileFormat",
 155                           "InstrProf"))
 156     SummaryKind = PSK_Instr;
 157   else
 158     return nullptr;
 159
 160   uint64_t NumCounts, TotalCount, NumFunctions, MaxFunctionCount, MaxCount,
 161       MaxInternalCount;
 162   if (!getVal(dyn_cast<MDTuple>(Tuple->getOperand(1)), "TotalCount",
 163               TotalCount))
 164     return nullptr;
 165   if (!getVal(dyn_cast<MDTuple>(Tuple->getOperand(2)), "MaxCount", MaxCount))
 166     return nullptr;
 167   if (!getVal(dyn_cast<MDTuple>(Tuple->getOperand(3)), "MaxInternalCount",
 168               MaxInternalCount))
 169     return nullptr;
 170   if (!getVal(dyn_cast<MDTuple>(Tuple->getOperand(4)), "MaxFunctionCount",
 171               MaxFunctionCount))
 172     return nullptr;
 173   if (!getVal(dyn_cast<MDTuple>(Tuple->getOperand(5)), "NumCounts", NumCounts))
 174     return nullptr;
 175   if (!getVal(dyn_cast<MDTuple>(Tuple->getOperand(6)), "NumFunctions",
 176               NumFunctions))
 177     return nullptr;
 178
 179   SummaryEntryVector Summary;
 180   if (!getSummaryFromMD(dyn_cast<MDTuple>(Tuple->getOperand(7)), Summary))
 181     return nullptr;
 182   return new ProfileSummary(SummaryKind, std::move(Summary), TotalCount,
 183                             MaxCount, MaxInternalCount, MaxFunctionCount,
 184                             NumCounts, NumFunctions);
 185 }