1 files changed, 81 insertions, 4 deletions

diff --git a/clang/lib/CodeGen/CodeGenPGO.cpp b/clang/lib/CodeGen/CodeGenPGO.cpp
index 2c0d93b394a..df043537dd4 100644
--- a/clang/lib/CodeGen/CodeGenPGO.cpp
+++ b/clang/lib/CodeGen/CodeGenPGO.cpp
@@ -18,11 +18,14 @@
 #include "clang/AST/StmtVisitor.h"
 #include "llvm/IR/Intrinsics.h"
 #include "llvm/IR/MDBuilder.h"
-#include "llvm/ProfileData/InstrProfReader.h"
 #include "llvm/Support/Endian.h"
 #include "llvm/Support/FileSystem.h"
 #include "llvm/Support/MD5.h"
 
+static llvm::cl::opt<bool> EnableValueProfiling(
+  "enable-value-profiling", llvm::cl::ZeroOrMore,
+  llvm::cl::desc("Enable value profiling"), llvm::cl::init(false));
+
 using namespace clang;
 using namespace CodeGen;
 
@@ -740,12 +743,83 @@ void CodeGenPGO::emitCounterIncrement(CGBuilderTy &Builder, const Stmt *S) {
                       Builder.getInt32(Counter)});
 }
 
+// This method either inserts a call to the profile run-time during
+// instrumentation or puts profile data into metadata for PGO use.
+void CodeGenPGO::valueProfile(CGBuilderTy &Builder, uint32_t ValueKind,
+    llvm::Instruction *ValueSite, llvm::Value *ValuePtr) {
+
+  if (!EnableValueProfiling)
+    return;
+
+  if (!ValuePtr || !ValueSite || !Builder.GetInsertBlock())
+    return;
+
+  bool InstrumentValueSites = CGM.getCodeGenOpts().ProfileInstrGenerate;
+  if (InstrumentValueSites && RegionCounterMap) {
+    llvm::LLVMContext &Ctx = CGM.getLLVMContext();
+    auto *I8PtrTy = llvm::Type::getInt8PtrTy(Ctx);
+    llvm::Value *Args[5] = {
+        llvm::ConstantExpr::getBitCast(FuncNameVar, I8PtrTy),
+        Builder.getInt64(FunctionHash),
+        Builder.CreatePtrToInt(ValuePtr, Builder.getInt64Ty()),
+        Builder.getInt32(ValueKind),
+        Builder.getInt32(NumValueSites[ValueKind]++)
+    };
+    Builder.CreateCall(
+        CGM.getIntrinsic(llvm::Intrinsic::instrprof_value_profile), Args);
+    return;
+  }
+
+  llvm::IndexedInstrProfReader *PGOReader = CGM.getPGOReader();
+  if (PGOReader && haveRegionCounts()) {
+    // We record the top most called three functions at each call site.
+    // Profile metadata contains "VP" string identifying this metadata
+    // as value profiling data, then a uint32_t value for the value profiling
+    // kind, a uint64_t value for the total number of times the call is
+    // executed, followed by the function hash and execution count (uint64_t)
+    // pairs for each function.
+    if (NumValueSites[ValueKind] >= ProfRecord->getNumValueSites(ValueKind))
+      return;
+    uint32_t NV = ProfRecord->getNumValueDataForSite(ValueKind,
+                                                     NumValueSites[ValueKind]);
+    std::unique_ptr<InstrProfValueData[]> VD =
+        ProfRecord->getValueForSite(ValueKind, NumValueSites[ValueKind]);
+
+    uint64_t Sum = 0;
+    for (uint32_t I = 0; I < NV; ++I)
+      Sum += VD[I].Count;
+
+    llvm::LLVMContext &Ctx = CGM.getLLVMContext();
+    llvm::MDBuilder MDHelper(Ctx);
+    SmallVector<llvm::Metadata*, 3> Vals;
+    Vals.push_back(MDHelper.createString("VP"));
+    Vals.push_back(MDHelper.createConstant(
+        llvm::ConstantInt::get(llvm::Type::getInt32Ty(Ctx), ValueKind)));
+    Vals.push_back(MDHelper.createConstant(
+        llvm::ConstantInt::get(llvm::Type::getInt64Ty(Ctx), Sum)));
+
+    uint32_t MDCount = 3;
+    for (uint32_t I = 0; I < NV; ++I) {
+      Vals.push_back(MDHelper.createConstant(
+          llvm::ConstantInt::get(llvm::Type::getInt64Ty(Ctx), VD[I].Value)));
+      Vals.push_back(MDHelper.createConstant(
+          llvm::ConstantInt::get(llvm::Type::getInt64Ty(Ctx), VD[I].Count)));
+      if (--MDCount == 0)
+        break;
+    }
+    ValueSite->setMetadata(
+        llvm::LLVMContext::MD_prof, llvm::MDNode::get(Ctx, Vals));
+    NumValueSites[ValueKind]++;
+  }
+}
+
 void CodeGenPGO::loadRegionCounts(llvm::IndexedInstrProfReader *PGOReader,
                                   bool IsInMainFile) {
   CGM.getPGOStats().addVisited(IsInMainFile);
   RegionCounts.clear();
-  if (std::error_code EC =
-          PGOReader->getFunctionCounts(FuncName, FunctionHash, RegionCounts)) {
+  llvm::ErrorOr<llvm::InstrProfRecord> RecordErrorOr =
+      PGOReader->getInstrProfRecord(FuncName, FunctionHash);
+  if (std::error_code EC = RecordErrorOr.getError()) {
     if (EC == llvm::instrprof_error::unknown_function)
       CGM.getPGOStats().addMissing(IsInMainFile);
     else if (EC == llvm::instrprof_error::hash_mismatch)
@@ -753,8 +827,11 @@ void CodeGenPGO::loadRegionCounts(llvm::IndexedInstrProfReader *PGOReader,
     else if (EC == llvm::instrprof_error::malformed)
       // TODO: Consider a more specific warning for this case.
       CGM.getPGOStats().addMismatched(IsInMainFile);
-    RegionCounts.clear();
+    return;
   }
+  ProfRecord =
+      llvm::make_unique<llvm::InstrProfRecord>(std::move(RecordErrorOr.get()));
+  RegionCounts = ProfRecord->Counts;
 }
 
 /// \brief Calculate what to divide by to scale weights.