Approved by Chris:

$ svn merge -c 113557 https://llvm.org/svn/llvm-project/llvm/trunk
--- Merging r113557 into '.':
U    include/llvm/Bitcode/LLVMBitCodes.h
U    tools/llvm-bcanalyzer/llvm-bcanalyzer.cpp
U    lib/Bitcode/Reader/BitcodeReader.cpp
U    lib/Bitcode/Writer/BitcodeWriter.cpp
$ svn merge -c 113764 https://llvm.org/svn/llvm-project/llvm/trunk
--- Merging r113764 into '.':
U    lib/Bitcode/Reader/BitcodeReader.h
G    lib/Bitcode/Reader/BitcodeReader.cpp
$ svn merge -c 113828 https://llvm.org/svn/llvm-project/llvm/trunk
--- Merging r113828 into '.':
U    lib/VMCore/Metadata.cpp



git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_28@113853 91177308-0d34-0410-b5e6-96231b3b80d8

4 files changed, 84 insertions, 18 deletions

diff --git a/lib/Bitcode/Reader/BitcodeReader.cpp b/lib/Bitcode/Reader/BitcodeReader.cpp
index cb7f2f40c4..ee55ebbbc5 100644
--- a/lib/Bitcode/Reader/BitcodeReader.cpp
+++ b/lib/Bitcode/Reader/BitcodeReader.cpp
@@ -774,7 +774,8 @@ bool BitcodeReader::ParseMetadata() {
     bool IsFunctionLocal = false;
     // Read a record.
     Record.clear();
-    switch (Stream.ReadRecord(Code, Record)) {
+    Code = Stream.ReadRecord(Code, Record);
+    switch (Code) {
     default:  // Default behavior: ignore.
       break;
     case bitc::METADATA_NAME: {
@@ -787,8 +788,12 @@ bool BitcodeReader::ParseMetadata() {
       Record.clear();
       Code = Stream.ReadCode();
 
-      // METADATA_NAME is always followed by METADATA_NAMED_NODE.
-      if (Stream.ReadRecord(Code, Record) != bitc::METADATA_NAMED_NODE)
+      // METADATA_NAME is always followed by METADATA_NAMED_NODE2.
+      // Or METADATA_NAMED_NODE in LLVM 2.7. FIXME: Remove this in LLVM 3.0.
+      unsigned NextBitCode = Stream.ReadRecord(Code, Record);
+      if (NextBitCode == bitc::METADATA_NAMED_NODE) {
+        LLVM2_7MetadataDetected = true;
+      } else if (NextBitCode != bitc::METADATA_NAMED_NODE2)
         assert ( 0 && "Inavlid Named Metadata record");
 
       // Read named metadata elements.
@@ -800,14 +805,29 @@ bool BitcodeReader::ParseMetadata() {
           return Error("Malformed metadata record");
         NMD->addOperand(MD);
       }
+      // Backwards compatibility hack: NamedMDValues used to be Values,
+      // and they got their own slots in the value numbering. They are no
+      // longer Values, however we still need to account for them in the
+      // numbering in order to be able to read old bitcode files.
+      // FIXME: Remove this in LLVM 3.0.
+      if (LLVM2_7MetadataDetected)
+        MDValueList.AssignValue(0, NextMDValueNo++);
       break;
     }
-    case bitc::METADATA_FN_NODE:
+    case bitc::METADATA_FN_NODE: // FIXME: Remove in LLVM 3.0.
+    case bitc::METADATA_FN_NODE2:
       IsFunctionLocal = true;
       // fall-through
-    case bitc::METADATA_NODE: {
+    case bitc::METADATA_NODE:    // FIXME: Remove in LLVM 3.0.
+    case bitc::METADATA_NODE2: {
+
+      // Detect 2.7-era metadata.
+      // FIXME: Remove in LLVM 3.0.
+      if (Code == bitc::METADATA_FN_NODE || Code == bitc::METADATA_NODE)
+        LLVM2_7MetadataDetected = true;
+
       if (Record.size() % 2 == 1)
-        return Error("Invalid METADATA_NODE record");
+        return Error("Invalid METADATA_NODE2 record");
 
       unsigned Size = Record.size();
       SmallVector<Value*, 8> Elts;
@@ -1594,7 +1614,10 @@ bool BitcodeReader::ParseMetadataAttachment() {
     switch (Stream.ReadRecord(Code, Record)) {
     default:  // Default behavior: ignore.
       break;
-    case bitc::METADATA_ATTACHMENT: {
+    // FIXME: Remove in LLVM 3.0.
+    case bitc::METADATA_ATTACHMENT:
+      LLVM2_7MetadataDetected = true;
+    case bitc::METADATA_ATTACHMENT2: {
       unsigned RecordLength = Record.size();
       if (Record.empty() || (RecordLength - 1) % 2 == 1)
         return Error ("Invalid METADATA_ATTACHMENT reader!");
@@ -1707,7 +1730,10 @@ bool BitcodeReader::ParseFunctionBody(Function *F) {
       I = 0;
       continue;
         
-    case bitc::FUNC_CODE_DEBUG_LOC: {      // DEBUG_LOC: [line, col, scope, ia]
+    // FIXME: Remove this in LLVM 3.0.
+    case bitc::FUNC_CODE_DEBUG_LOC:
+      LLVM2_7MetadataDetected = true;
+    case bitc::FUNC_CODE_DEBUG_LOC2: {      // DEBUG_LOC: [line, col, scope, ia]
       I = 0;     // Get the last instruction emitted.
       if (CurBB && !CurBB->empty())
         I = &CurBB->back();
@@ -2169,7 +2195,7 @@ bool BitcodeReader::ParseFunctionBody(Function *F) {
     }
     case bitc::FUNC_CODE_INST_ALLOCA: { // ALLOCA: [instty, opty, op, align]
       // For backward compatibility, tolerate a lack of an opty, and use i32.
-      // LLVM 3.0: Remove this.
+      // Remove this in LLVM 3.0.
       if (Record.size() < 3 || Record.size() > 4)
         return Error("Invalid ALLOCA record");
       unsigned OpNum = 0;
@@ -2222,7 +2248,10 @@ bool BitcodeReader::ParseFunctionBody(Function *F) {
       InstructionList.push_back(I);
       break;
     }
-    case bitc::FUNC_CODE_INST_CALL: {
+    // FIXME: Remove this in LLVM 3.0.
+    case bitc::FUNC_CODE_INST_CALL:
+      LLVM2_7MetadataDetected = true;
+    case bitc::FUNC_CODE_INST_CALL2: {
       // CALL: [paramattrs, cc, fnty, fnid, arg0, arg1...]
       if (Record.size() < 3)
         return Error("Invalid CALL record");
@@ -2341,9 +2370,21 @@ bool BitcodeReader::ParseFunctionBody(Function *F) {
     BlockAddrFwdRefs.erase(BAFRI);
   }
   
+  // FIXME: Remove this in LLVM 3.0.
+  unsigned NewMDValueListSize = MDValueList.size();
+
   // Trim the value list down to the size it was before we parsed this function.
   ValueList.shrinkTo(ModuleValueListSize);
   MDValueList.shrinkTo(ModuleMDValueListSize);
+
+  // Backwards compatibility hack: Function-local metadata numbers
+  // were previously not reset between functions. This is now fixed,
+  // however we still need to understand the old numbering in order
+  // to be able to read old bitcode files.
+  // FIXME: Remove this in LLVM 3.0.
+  if (LLVM2_7MetadataDetected)
+    MDValueList.resize(NewMDValueListSize);
+
   std::vector<BasicBlock*>().swap(FunctionBBs);
 
   return false;
diff --git a/lib/Bitcode/Reader/BitcodeReader.h b/lib/Bitcode/Reader/BitcodeReader.h
index a5ab5d29e9..053121bdad 100644
--- a/lib/Bitcode/Reader/BitcodeReader.h
+++ b/lib/Bitcode/Reader/BitcodeReader.h
@@ -173,11 +173,18 @@ class BitcodeReader : public GVMaterializer {
   /// are resolved lazily when functions are loaded.
   typedef std::pair<unsigned, GlobalVariable*> BlockAddrRefTy;
   DenseMap<Function*, std::vector<BlockAddrRefTy> > BlockAddrFwdRefs;
+
+  /// LLVM2_7MetadataDetected - True if metadata produced by LLVM 2.7 or
+  /// earlier was detected, in which case we behave slightly differently,
+  /// for compatibility.
+  /// FIXME: Remove in LLVM 3.0.
+  bool LLVM2_7MetadataDetected;
   
 public:
   explicit BitcodeReader(MemoryBuffer *buffer, LLVMContext &C)
     : Context(C), TheModule(0), Buffer(buffer), BufferOwned(false),
-      ErrorString(0), ValueList(C), MDValueList(C) {
+      ErrorString(0), ValueList(C), MDValueList(C),
+      LLVM2_7MetadataDetected(false) {
     HasReversedFunctionsWithBodies = false;
   }
   ~BitcodeReader() {
diff --git a/lib/Bitcode/Writer/BitcodeWriter.cpp b/lib/Bitcode/Writer/BitcodeWriter.cpp
index 07727f33d9..7b6fc6cd92 100644
--- a/lib/Bitcode/Writer/BitcodeWriter.cpp
+++ b/lib/Bitcode/Writer/BitcodeWriter.cpp
@@ -485,8 +485,8 @@ static void WriteMDNode(const MDNode *N,
       Record.push_back(0);
     }
   }
-  unsigned MDCode = N->isFunctionLocal() ? bitc::METADATA_FN_NODE :
-                                           bitc::METADATA_NODE;
+  unsigned MDCode = N->isFunctionLocal() ? bitc::METADATA_FN_NODE2 :
+                                           bitc::METADATA_NODE2;
   Stream.EmitRecord(MDCode, Record, 0);
   Record.clear();
 }
@@ -549,7 +549,7 @@ static void WriteModuleMetadata(const Module *M,
     // Write named metadata operands.
     for (unsigned i = 0, e = NMD->getNumOperands(); i != e; ++i)
       Record.push_back(VE.getValueID(NMD->getOperand(i)));
-    Stream.EmitRecord(bitc::METADATA_NAMED_NODE, Record, 0);
+    Stream.EmitRecord(bitc::METADATA_NAMED_NODE2, Record, 0);
     Record.clear();
   }
 
@@ -585,7 +585,7 @@ static void WriteMetadataAttachment(const Function &F,
   SmallVector<uint64_t, 64> Record;
 
   // Write metadata attachments
-  // METADATA_ATTACHMENT - [m x [value, [n x [id, mdnode]]]
+  // METADATA_ATTACHMENT2 - [m x [value, [n x [id, mdnode]]]
   SmallVector<std::pair<unsigned, MDNode*>, 4> MDs;
   
   for (Function::const_iterator BB = F.begin(), E = F.end(); BB != E; ++BB)
@@ -603,7 +603,7 @@ static void WriteMetadataAttachment(const Function &F,
         Record.push_back(MDs[i].first);
         Record.push_back(VE.getValueID(MDs[i].second));
       }
-      Stream.EmitRecord(bitc::METADATA_ATTACHMENT, Record, 0);
+      Stream.EmitRecord(bitc::METADATA_ATTACHMENT2, Record, 0);
       Record.clear();
     }
 
@@ -1111,7 +1111,7 @@ static void WriteInstruction(const Instruction &I, unsigned InstID,
     const PointerType *PTy = cast<PointerType>(CI.getCalledValue()->getType());
     const FunctionType *FTy = cast<FunctionType>(PTy->getElementType());
 
-    Code = bitc::FUNC_CODE_INST_CALL;
+    Code = bitc::FUNC_CODE_INST_CALL2;
 
     Vals.push_back(VE.getAttributeID(CI.getAttributes()));
     Vals.push_back((CI.getCallingConv() << 1) | unsigned(CI.isTailCall()));
@@ -1255,7 +1255,7 @@ static void WriteFunction(const Function &F, ValueEnumerator &VE,
         Vals.push_back(DL.getCol());
         Vals.push_back(Scope ? VE.getValueID(Scope)+1 : 0);
         Vals.push_back(IA ? VE.getValueID(IA)+1 : 0);
-        Stream.EmitRecord(bitc::FUNC_CODE_DEBUG_LOC, Vals);
+        Stream.EmitRecord(bitc::FUNC_CODE_DEBUG_LOC2, Vals);
         Vals.clear();
         
         LastDL = DL;
diff --git a/lib/VMCore/Metadata.cpp b/lib/VMCore/Metadata.cpp
index b9f97dbf60..da69c43ff7 100644
--- a/lib/VMCore/Metadata.cpp
+++ b/lib/VMCore/Metadata.cpp
@@ -354,6 +354,22 @@ void MDNode::replaceOperand(MDNodeOperand *Op, Value *To) {
 
   // InsertPoint will have been set by the FindNodeOrInsertPos call.
   pImpl->MDNodeSet.InsertNode(this, InsertPoint);
+
+  // If this MDValue was previously function-local but no longer is, clear
+  // its function-local flag.
+  if (isFunctionLocal() && !isFunctionLocalValue(To)) {
+    bool isStillFunctionLocal = false;
+    for (unsigned i = 0, e = getNumOperands(); i != e; ++i) {
+      Value *V = getOperand(i);
+      if (!V) continue;
+      if (isFunctionLocalValue(V)) {
+        isStillFunctionLocal = true;
+        break;
+      }
+    }
+    if (!isStillFunctionLocal)
+      setValueSubclassData(getSubclassDataFromValue() & ~FunctionLocalBit);
+  }
 }
 
 //===----------------------------------------------------------------------===//
@@ -387,6 +403,8 @@ MDNode *NamedMDNode::getOperand(unsigned i) const {
 
 /// addOperand - Add metadata Operand.
 void NamedMDNode::addOperand(MDNode *M) {
+  assert(!M->isFunctionLocal() &&
+         "NamedMDNode operands must not be function-local!");
   getNMDOps(Operands).push_back(TrackingVH<MDNode>(M));
 }