Reorganize GlobalValueSummary with a "Flags" bitfield.

Right now it only contains the LinkageType, but will be extended
with "hasSection", "isOptSize", "hasInlineAssembly", etc.

Differential Revision: http://reviews.llvm.org/D19404

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 267319

2 files changed, 61 insertions, 39 deletions

diff --git a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
index 8b583fe4995..0e29c0e77d7 100644
--- a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
+++ b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
@@ -738,6 +738,16 @@ static GlobalValue::LinkageTypes getDecodedLinkage(unsigned Val) {
   }
 }
 
+// Decode the flags for GlobalValue in the summary
+static GlobalValueSummary::GVFlags getDecodedGVSummaryFlags(uint64_t RawFlags,
+                                                            uint64_t Version) {
+  // Summary were not emitted before LLVM 3.9, we don't need to upgrade Linkage
+  // like getDecodedLinkage() above. Any future change to the linkage enum and
+  // to getDecodedLinkage() will need to be taken into account here as above.
+  auto Linkage = GlobalValue::LinkageTypes(RawFlags & 0xF); // 4 bits
+  return GlobalValueSummary::GVFlags(Linkage);
+}
+
 static GlobalValue::VisibilityTypes getDecodedVisibility(unsigned Val) {
   switch (Val) {
   default: // Map unknown visibilities to default.
@@ -6051,19 +6061,20 @@ std::error_code ModuleSummaryIndexBitcodeReader::parseEntireSummary() {
     switch (BitCode) {
     default: // Default behavior: ignore.
       break;
-    // FS_PERMODULE: [valueid, linkage, instcount, numrefs, numrefs x valueid,
+    // FS_PERMODULE: [valueid, flags, instcount, numrefs, numrefs x valueid,
     //                n x (valueid, callsitecount)]
-    // FS_PERMODULE_PROFILE: [valueid, linkage, instcount, numrefs,
+    // FS_PERMODULE_PROFILE: [valueid, flags, instcount, numrefs,
     //                        numrefs x valueid,
     //                        n x (valueid, callsitecount, profilecount)]
     case bitc::FS_PERMODULE:
     case bitc::FS_PERMODULE_PROFILE: {
       unsigned ValueID = Record[0];
-      uint64_t RawLinkage = Record[1];
+      uint64_t RawFlags = Record[1];
       unsigned InstCount = Record[2];
       unsigned NumRefs = Record[3];
-      std::unique_ptr<FunctionSummary> FS = llvm::make_unique<FunctionSummary>(
-          getDecodedLinkage(RawLinkage), InstCount);
+      auto Flags = getDecodedGVSummaryFlags(RawFlags, Version);
+      std::unique_ptr<FunctionSummary> FS =
+          llvm::make_unique<FunctionSummary>(Flags, InstCount);
       // 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
@@ -6097,15 +6108,15 @@ std::error_code ModuleSummaryIndexBitcodeReader::parseEntireSummary() {
       Info->setSummary(std::move(FS));
       break;
     }
-    // FS_ALIAS: [valueid, linkage, valueid]
+    // FS_ALIAS: [valueid, flags, valueid]
     // Aliases must be emitted (and parsed) after all FS_PERMODULE entries, as
     // they expect all aliasee summaries to be available.
     case bitc::FS_ALIAS: {
       unsigned ValueID = Record[0];
-      uint64_t RawLinkage = Record[1];
+      uint64_t RawFlags = Record[1];
       unsigned AliaseeID = Record[2];
-      std::unique_ptr<AliasSummary> AS =
-          llvm::make_unique<AliasSummary>(getDecodedLinkage(RawLinkage));
+      auto Flags = getDecodedGVSummaryFlags(RawFlags, Version);
+      std::unique_ptr<AliasSummary> AS = llvm::make_unique<AliasSummary>(Flags);
       // 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
@@ -6127,12 +6138,13 @@ std::error_code ModuleSummaryIndexBitcodeReader::parseEntireSummary() {
       Info->setSummary(std::move(AS));
       break;
     }
-    // FS_PERMODULE_GLOBALVAR_INIT_REFS: [valueid, linkage, n x valueid]
+    // FS_PERMODULE_GLOBALVAR_INIT_REFS: [valueid, flags, n x valueid]
     case bitc::FS_PERMODULE_GLOBALVAR_INIT_REFS: {
       unsigned ValueID = Record[0];
-      uint64_t RawLinkage = Record[1];
+      uint64_t RawFlags = Record[1];
+      auto Flags = getDecodedGVSummaryFlags(RawFlags, Version);
       std::unique_ptr<GlobalVarSummary> FS =
-          llvm::make_unique<GlobalVarSummary>(getDecodedLinkage(RawLinkage));
+          llvm::make_unique<GlobalVarSummary>(Flags);
       FS->setModulePath(
           TheIndex->addModulePath(Buffer->getBufferIdentifier(), 0)->first());
       for (unsigned I = 2, E = Record.size(); I != E; ++I) {
@@ -6147,19 +6159,20 @@ std::error_code ModuleSummaryIndexBitcodeReader::parseEntireSummary() {
       Info->setSummary(std::move(FS));
       break;
     }
-    // FS_COMBINED: [modid, linkage, instcount, numrefs, numrefs x valueid,
+    // FS_COMBINED: [modid, flags, instcount, numrefs, numrefs x valueid,
     //               n x (valueid, callsitecount)]
-    // FS_COMBINED_PROFILE: [modid, linkage, instcount, numrefs,
+    // FS_COMBINED_PROFILE: [modid, flags, instcount, numrefs,
     //                       numrefs x valueid,
     //                       n x (valueid, callsitecount, profilecount)]
     case bitc::FS_COMBINED:
     case bitc::FS_COMBINED_PROFILE: {
       uint64_t ModuleId = Record[0];
-      uint64_t RawLinkage = Record[1];
+      uint64_t RawFlags = Record[1];
       unsigned InstCount = Record[2];
       unsigned NumRefs = Record[3];
-      std::unique_ptr<FunctionSummary> FS = llvm::make_unique<FunctionSummary>(
-          getDecodedLinkage(RawLinkage), InstCount);
+      auto Flags = getDecodedGVSummaryFlags(RawFlags, Version);
+      std::unique_ptr<FunctionSummary> FS =
+          llvm::make_unique<FunctionSummary>(Flags, InstCount);
       LastSeenSummary = FS.get();
       FS->setModulePath(ModuleIdMap[ModuleId]);
       static int RefListStartIndex = 4;
@@ -6187,15 +6200,15 @@ std::error_code ModuleSummaryIndexBitcodeReader::parseEntireSummary() {
       Combined = true;
       break;
     }
-    // FS_COMBINED_ALIAS: [modid, linkage, offset]
+    // FS_COMBINED_ALIAS: [modid, flags, offset]
     // Aliases must be emitted (and parsed) after all FS_COMBINED entries, as
     // they expect all aliasee summaries to be available.
     case bitc::FS_COMBINED_ALIAS: {
       uint64_t ModuleId = Record[0];
-      uint64_t RawLinkage = Record[1];
+      uint64_t RawFlags = Record[1];
       uint64_t AliaseeSummaryOffset = Record[2];
-      std::unique_ptr<AliasSummary> AS =
-          llvm::make_unique<AliasSummary>(getDecodedLinkage(RawLinkage));
+      auto Flags = getDecodedGVSummaryFlags(RawFlags, Version);
+      std::unique_ptr<AliasSummary> AS = llvm::make_unique<AliasSummary>(Flags);
       LastSeenSummary = AS.get();
       AS->setModulePath(ModuleIdMap[ModuleId]);
 
@@ -6210,12 +6223,13 @@ std::error_code ModuleSummaryIndexBitcodeReader::parseEntireSummary() {
       Combined = true;
       break;
     }
-    // FS_COMBINED_GLOBALVAR_INIT_REFS: [modid, linkage, n x valueid]
+    // FS_COMBINED_GLOBALVAR_INIT_REFS: [modid, flags, n x valueid]
     case bitc::FS_COMBINED_GLOBALVAR_INIT_REFS: {
       uint64_t ModuleId = Record[0];
-      uint64_t RawLinkage = Record[1];
+      uint64_t RawFlags = Record[1];
+      auto Flags = getDecodedGVSummaryFlags(RawFlags, Version);
       std::unique_ptr<GlobalVarSummary> FS =
-          llvm::make_unique<GlobalVarSummary>(getDecodedLinkage(RawLinkage));
+          llvm::make_unique<GlobalVarSummary>(Flags);
       LastSeenSummary = FS.get();
       FS->setModulePath(ModuleIdMap[ModuleId]);
       for (unsigned I = 2, E = Record.size(); I != E; ++I) {
diff --git a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
index d0f87e7d9d0..d642dd4be23 100644
--- a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
+++ b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
@@ -786,6 +786,14 @@ static unsigned getEncodedLinkage(const GlobalValue &GV) {
   return getEncodedLinkage(GV.getLinkage());
 }
 
+// Decode the flags for GlobalValue in the summary
+static uint64_t getEncodedGVSummaryFlags(GlobalValueSummary::GVFlags Flags) {
+  uint64_t RawFlags = 0;
+  // Emit Linkage enum.
+  RawFlags |= Flags.Linkage; // 4 bits
+  return RawFlags;
+}
+
 static unsigned getEncodedVisibility(const GlobalValue &GV) {
   switch (GV.getVisibility()) {
   case GlobalValue::DefaultVisibility:   return 0;
@@ -3023,7 +3031,7 @@ void ModuleBitcodeWriter::writePerModuleFunctionSummaryRecord(
   NameVals.push_back(ValueID);
 
   FunctionSummary *FS = cast<FunctionSummary>(Info->summary());
-  NameVals.push_back(getEncodedLinkage(FS->linkage()));
+  NameVals.push_back(getEncodedGVSummaryFlags(FS->flags()));
   NameVals.push_back(FS->instCount());
   NameVals.push_back(FS->refs().size());
 
@@ -3057,7 +3065,7 @@ void ModuleBitcodeWriter::writeModuleLevelReferences(
   if (V.isDeclaration())
     return;
   NameVals.push_back(VE.getValueID(&V));
-  NameVals.push_back(getEncodedLinkage(V.getLinkage()));
+  NameVals.push_back(getEncodedGVSummaryFlags(V));
   auto *Info = Index->getGlobalValueInfo(V);
   GlobalVarSummary *VS = cast<GlobalVarSummary>(Info->summary());
   for (auto Ref : VS->refs())
@@ -3081,7 +3089,7 @@ void ModuleBitcodeWriter::writePerModuleGlobalValueSummary() {
   if (Index->begin() == Index->end())
     return;
 
-  Stream.EnterSubblock(bitc::GLOBALVAL_SUMMARY_BLOCK_ID, 3);
+  Stream.EnterSubblock(bitc::GLOBALVAL_SUMMARY_BLOCK_ID, 4);
 
   Stream.EmitRecord(bitc::FS_VERSION, ArrayRef<uint64_t>{INDEX_VERSION});
 
@@ -3089,7 +3097,7 @@ void ModuleBitcodeWriter::writePerModuleGlobalValueSummary() {
   BitCodeAbbrev *Abbv = new BitCodeAbbrev();
   Abbv->Add(BitCodeAbbrevOp(bitc::FS_PERMODULE));
   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));   // valueid
-  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 5)); // linkage
+  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // flags
   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));   // instcount
   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 4));   // numrefs
   // numrefs x valueid, n x (valueid, callsitecount)
@@ -3101,7 +3109,7 @@ void ModuleBitcodeWriter::writePerModuleGlobalValueSummary() {
   Abbv = new BitCodeAbbrev();
   Abbv->Add(BitCodeAbbrevOp(bitc::FS_PERMODULE_PROFILE));
   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));   // valueid
-  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 5)); // linkage
+  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // flags
   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));   // instcount
   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 4));   // numrefs
   // numrefs x valueid, n x (valueid, callsitecount, profilecount)
@@ -3113,7 +3121,7 @@ void ModuleBitcodeWriter::writePerModuleGlobalValueSummary() {
   Abbv = new BitCodeAbbrev();
   Abbv->Add(BitCodeAbbrevOp(bitc::FS_PERMODULE_GLOBALVAR_INIT_REFS));
   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8)); // valueid
-  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 5)); // linkage
+  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // flags
   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));  // valueids
   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
   unsigned FSModRefsAbbrev = Stream.EmitAbbrev(Abbv);
@@ -3122,7 +3130,7 @@ void ModuleBitcodeWriter::writePerModuleGlobalValueSummary() {
   Abbv = new BitCodeAbbrev();
   Abbv->Add(BitCodeAbbrevOp(bitc::FS_ALIAS));
   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));   // valueid
-  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 5)); // linkage
+  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // flags
   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));   // valueid
   unsigned FSAliasAbbrev = Stream.EmitAbbrev(Abbv);
 
@@ -3157,7 +3165,7 @@ void ModuleBitcodeWriter::writePerModuleGlobalValueSummary() {
     auto AliasId = VE.getValueID(&A);
     auto AliaseeId = VE.getValueID(Aliasee);
     NameVals.push_back(AliasId);
-    NameVals.push_back(getEncodedLinkage(A.getLinkage()));
+    NameVals.push_back(getEncodedGVSummaryFlags(A));
     NameVals.push_back(AliaseeId);
     Stream.EmitRecord(bitc::FS_ALIAS, NameVals, FSAliasAbbrev);
     NameVals.clear();
@@ -3175,7 +3183,7 @@ void IndexBitcodeWriter::writeCombinedGlobalValueSummary() {
   BitCodeAbbrev *Abbv = new BitCodeAbbrev();
   Abbv->Add(BitCodeAbbrevOp(bitc::FS_COMBINED));
   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));   // modid
-  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 5)); // linkage
+  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // flags
   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));   // instcount
   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 4));   // numrefs
   // numrefs x valueid, n x (valueid, callsitecount)
@@ -3187,7 +3195,7 @@ void IndexBitcodeWriter::writeCombinedGlobalValueSummary() {
   Abbv = new BitCodeAbbrev();
   Abbv->Add(BitCodeAbbrevOp(bitc::FS_COMBINED_PROFILE));
   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));   // modid
-  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 5)); // linkage
+  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // flags
   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));   // instcount
   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 4));   // numrefs
   // numrefs x valueid, n x (valueid, callsitecount, profilecount)
@@ -3199,7 +3207,7 @@ void IndexBitcodeWriter::writeCombinedGlobalValueSummary() {
   Abbv = new BitCodeAbbrev();
   Abbv->Add(BitCodeAbbrevOp(bitc::FS_COMBINED_GLOBALVAR_INIT_REFS));
   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));   // modid
-  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 5)); // linkage
+  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // flags
   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));    // valueids
   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
   unsigned FSModRefsAbbrev = Stream.EmitAbbrev(Abbv);
@@ -3208,7 +3216,7 @@ void IndexBitcodeWriter::writeCombinedGlobalValueSummary() {
   Abbv = new BitCodeAbbrev();
   Abbv->Add(BitCodeAbbrevOp(bitc::FS_COMBINED_ALIAS));
   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));   // modid
-  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 5)); // linkage
+  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // flags
   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));   // offset
   unsigned FSAliasAbbrev = Stream.EmitAbbrev(Abbv);
 
@@ -3243,7 +3251,7 @@ void IndexBitcodeWriter::writeCombinedGlobalValueSummary() {
 
       if (auto *VS = dyn_cast<GlobalVarSummary>(S)) {
         NameVals.push_back(Index.getModuleId(VS->modulePath()));
-        NameVals.push_back(getEncodedLinkage(VS->linkage()));
+        NameVals.push_back(getEncodedGVSummaryFlags(VS->flags()));
         for (auto &RI : VS->refs()) {
           NameVals.push_back(getValueId(RI.getGUID()));
         }
@@ -3266,7 +3274,7 @@ void IndexBitcodeWriter::writeCombinedGlobalValueSummary() {
 
       auto *FS = cast<FunctionSummary>(S);
       NameVals.push_back(Index.getModuleId(FS->modulePath()));
-      NameVals.push_back(getEncodedLinkage(FS->linkage()));
+      NameVals.push_back(getEncodedGVSummaryFlags(FS->flags()));
       NameVals.push_back(FS->instCount());
       NameVals.push_back(FS->refs().size());
 
@@ -3315,7 +3323,7 @@ void IndexBitcodeWriter::writeCombinedGlobalValueSummary() {
   for (auto GVI : Aliases) {
     AliasSummary *AS = cast<AliasSummary>(GVI->summary());
     NameVals.push_back(Index.getModuleId(AS->modulePath()));
-    NameVals.push_back(getEncodedLinkage(AS->linkage()));
+    NameVals.push_back(getEncodedGVSummaryFlags(AS->flags()));
     auto AliaseeOffset = SummaryToOffsetMap[&AS->getAliasee()];
     assert(AliaseeOffset);
     NameVals.push_back(AliaseeOffset);