[ThinLTO] Include linkage type in function summary

Summary:
Adds the linkage type to both the per-module and combined function
summaries, which subsumes the current islocal bit. This will eventually
be used to optimized linkage types based on global summary-based
analysis.

Reviewers: joker.eph

Subscribers: joker.eph, davidxl, llvm-commits

Differential Revision: http://reviews.llvm.org/D16943

llvm-svn: 259993

2 files changed, 18 insertions, 10 deletions

diff --git a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
index 36650dbe05a..176d836bf13 100644
--- a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
+++ b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
@@ -5592,14 +5592,14 @@ std::error_code FunctionIndexBitcodeReader::parseEntireSummary() {
     switch (Stream.readRecord(Entry.ID, Record)) {
     default: // Default behavior: ignore.
       break;
-    // FS_PERMODULE_ENTRY: [valueid, islocal, instcount]
+    // FS_PERMODULE_ENTRY: [valueid, linkage, instcount]
     case bitc::FS_CODE_PERMODULE_ENTRY: {
       unsigned ValueID = Record[0];
-      bool IsLocal = Record[1];
+      uint64_t RawLinkage = Record[1];
       unsigned InstCount = Record[2];
       std::unique_ptr<FunctionSummary> FS =
           llvm::make_unique<FunctionSummary>(InstCount);
-      FS->setLocalFunction(IsLocal);
+      FS->setFunctionLinkage(getDecodedLinkage(RawLinkage));
       // The module path string ref set in the summary must be owned by the
       // index's module string table. Since we don't have a module path
       // string table section in the per-module index, we create a single
@@ -5609,12 +5609,14 @@ std::error_code FunctionIndexBitcodeReader::parseEntireSummary() {
           TheIndex->addModulePath(Buffer->getBufferIdentifier(), 0));
       SummaryMap[ValueID] = std::move(FS);
     }
-    // FS_COMBINED_ENTRY: [modid, instcount]
+    // FS_COMBINED_ENTRY: [modid, linkage, instcount]
     case bitc::FS_CODE_COMBINED_ENTRY: {
       uint64_t ModuleId = Record[0];
-      unsigned InstCount = Record[1];
+      uint64_t RawLinkage = Record[1];
+      unsigned InstCount = Record[2];
       std::unique_ptr<FunctionSummary> FS =
           llvm::make_unique<FunctionSummary>(InstCount);
+      FS->setFunctionLinkage(getDecodedLinkage(RawLinkage));
       FS->setModulePath(ModuleIdMap[ModuleId]);
       SummaryMap[CurRecordBit] = std::move(FS);
     }
diff --git a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
index 5f85882cd40..bccd0430a09 100644
--- a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
+++ b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
@@ -496,8 +496,8 @@ static void WriteTypeTable(const ValueEnumerator &VE, BitstreamWriter &Stream) {
   Stream.ExitBlock();
 }
 
-static unsigned getEncodedLinkage(const GlobalValue &GV) {
-  switch (GV.getLinkage()) {
+static unsigned getEncodedLinkage(const GlobalValue::LinkageTypes Linkage) {
+  switch (Linkage) {
   case GlobalValue::ExternalLinkage:
     return 0;
   case GlobalValue::WeakAnyLinkage:
@@ -524,6 +524,10 @@ static unsigned getEncodedLinkage(const GlobalValue &GV) {
   llvm_unreachable("Invalid linkage");
 }
 
+static unsigned getEncodedLinkage(const GlobalValue &GV) {
+  return getEncodedLinkage(GV.getLinkage());
+}
+
 static unsigned getEncodedVisibility(const GlobalValue &GV) {
   switch (GV.getVisibility()) {
   case GlobalValue::DefaultVisibility:   return 0;
@@ -2449,7 +2453,7 @@ static void SaveFunctionInfo(
   std::unique_ptr<FunctionSummary> FuncSummary;
   if (EmitFunctionSummary) {
     FuncSummary = llvm::make_unique<FunctionSummary>(NumInsts);
-    FuncSummary->setLocalFunction(F.hasLocalLinkage());
+    FuncSummary->setFunctionLinkage(F.getLinkage());
   }
   FunctionIndex[&F] =
       llvm::make_unique<FunctionInfo>(BitcodeIndex, std::move(FuncSummary));
@@ -2776,7 +2780,7 @@ static void WritePerModuleFunctionSummaryRecord(
     unsigned FSAbbrev, BitstreamWriter &Stream) {
   assert(FS);
   NameVals.push_back(ValueID);
-  NameVals.push_back(FS->isLocalFunction());
+  NameVals.push_back(getEncodedLinkage(FS->getFunctionLinkage()));
   NameVals.push_back(FS->instCount());
 
   // Emit the finished record.
@@ -2795,7 +2799,7 @@ static void WritePerModuleFunctionSummary(
   BitCodeAbbrev *Abbv = new BitCodeAbbrev();
   Abbv->Add(BitCodeAbbrevOp(bitc::FS_CODE_PERMODULE_ENTRY));
   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));   // valueid
-  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // islocal
+  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 5)); // linkage
   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));   // instcount
   unsigned FSAbbrev = Stream.EmitAbbrev(Abbv);
 
@@ -2845,6 +2849,7 @@ static void WriteCombinedFunctionSummary(const FunctionInfoIndex &I,
   BitCodeAbbrev *Abbv = new BitCodeAbbrev();
   Abbv->Add(BitCodeAbbrevOp(bitc::FS_CODE_COMBINED_ENTRY));
   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8)); // modid
+  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 5)); // linkage
   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8)); // instcount
   unsigned FSAbbrev = Stream.EmitAbbrev(Abbv);
 
@@ -2855,6 +2860,7 @@ static void WriteCombinedFunctionSummary(const FunctionInfoIndex &I,
       assert(FS);
 
       NameVals.push_back(I.getModuleId(FS->modulePath()));
+      NameVals.push_back(getEncodedLinkage(FS->getFunctionLinkage()));
       NameVals.push_back(FS->instCount());
 
       // Record the starting offset of this summary entry for use