Initial import of LLVM 3.3

lib/Bitcode/Reader/BitcodeReader.h

@@ -14,27 +14,27 @@
 #ifndef BITCODE_READER_H
 #define BITCODE_READER_H
 
-#include "llvm/GVMaterializer.h"
-#include "llvm/Attributes.h"
-#include "llvm/Type.h"
-#include "llvm/OperandTraits.h"
+#include "llvm/ADT/DenseMap.h"
 #include "llvm/Bitcode/BitstreamReader.h"
 #include "llvm/Bitcode/LLVMBitCodes.h"
+#include "llvm/GVMaterializer.h"
+#include "llvm/IR/Attributes.h"
+#include "llvm/IR/OperandTraits.h"
+#include "llvm/IR/Type.h"
 #include "llvm/Support/ValueHandle.h"
-#include "llvm/ADT/DenseMap.h"
 #include <vector>
 
 namespace llvm {
   class MemoryBuffer;
   class LLVMContext;
-  
+
 //===----------------------------------------------------------------------===//
 //                          BitcodeReaderValueList Class
 //===----------------------------------------------------------------------===//
 
 class BitcodeReaderValueList {
   std::vector<WeakVH> ValuePtrs;
-  
+
   /// ResolveConstants - As we resolve forward-referenced constants, we add
   /// information about them to this vector.  This allows us to resolve them in
   /// bulk instead of resolving each reference at a time.  See the code in
@@ -57,17 +57,17 @@ public:
   void push_back(Value *V) {
     ValuePtrs.push_back(V);
   }
-  
+
   void clear() {
     assert(ResolveConstants.empty() && "Constants not resolved?");
     ValuePtrs.clear();
   }
-  
+
   Value *operator[](unsigned i) const {
     assert(i < ValuePtrs.size());
     return ValuePtrs[i];
   }
-  
+
   Value *back() const { return ValuePtrs.back(); }
     void pop_back() { ValuePtrs.pop_back(); }
   bool empty() const { return ValuePtrs.empty(); }
@@ -75,12 +75,12 @@ public:
     assert(N <= size() && "Invalid shrinkTo request!");
     ValuePtrs.resize(N);
   }
-  
+
   Constant *getConstantFwdRef(unsigned Idx, Type *Ty);
   Value *getValueFwdRef(unsigned Idx, Type *Ty);
-  
+
   void AssignValue(Value *V, unsigned Idx);
-  
+
   /// ResolveConstantForwardRefs - Once all constants are read, this method bulk
   /// resolves any forward references.
   void ResolveConstantForwardRefs();
@@ -93,7 +93,7 @@ public:
 
 class BitcodeReaderMDValueList {
   std::vector<WeakVH> MDValuePtrs;
-  
+
   LLVMContext &Context;
 public:
   BitcodeReaderMDValueList(LLVMContext& C) : Context(C) {}
@@ -106,12 +106,12 @@ public:
   Value *back() const         { return MDValuePtrs.back(); }
   void pop_back()             { MDValuePtrs.pop_back(); }
   bool empty() const          { return MDValuePtrs.empty(); }
-  
+
   Value *operator[](unsigned i) const {
     assert(i < MDValuePtrs.size());
     return MDValuePtrs[i];
   }
-  
+
   void shrinkTo(unsigned N) {
     assert(N <= size() && "Invalid shrinkTo request!");
     MDValuePtrs.resize(N);
@@ -131,9 +131,9 @@ class BitcodeReader : public GVMaterializer {
   DataStreamer *LazyStreamer;
   uint64_t NextUnreadBit;
   bool SeenValueSymbolTable;
-  
+
   const char *ErrorString;
-  
+
   std::vector<Type*> TypeList;
   BitcodeReaderValueList ValueList;
   BitcodeReaderMDValueList MDValueList;
@@ -142,55 +142,67 @@ class BitcodeReader : public GVMaterializer {
 
   std::vector<std::pair<GlobalVariable*, unsigned> > GlobalInits;
   std::vector<std::pair<GlobalAlias*, unsigned> > AliasInits;
-  
+
   /// MAttributes - The set of attributes by index.  Index zero in the
   /// file is for null, and is thus not represented here.  As such all indices
   /// are off by one.
-  std::vector<AttrListPtr> MAttributes;
-  
+  std::vector<AttributeSet> MAttributes;
+
+  /// \brief The set of attribute groups.
+  std::map<unsigned, AttributeSet> MAttributeGroups;
+
   /// FunctionBBs - While parsing a function body, this is a list of the basic
   /// blocks for the function.
   std::vector<BasicBlock*> FunctionBBs;
-  
+
   // When reading the module header, this list is populated with functions that
   // have bodies later in the file.
   std::vector<Function*> FunctionsWithBodies;
 
-  // When intrinsic functions are encountered which require upgrading they are 
+  // When intrinsic functions are encountered which require upgrading they are
   // stored here with their replacement function.
   typedef std::vector<std::pair<Function*, Function*> > UpgradedIntrinsicMap;
   UpgradedIntrinsicMap UpgradedIntrinsics;
 
   // Map the bitcode's custom MDKind ID to the Module's MDKind ID.
   DenseMap<unsigned, unsigned> MDKindMap;
-  
+
   // Several operations happen after the module header has been read, but
   // before function bodies are processed. This keeps track of whether
   // we've done this yet.
   bool SeenFirstFunctionBody;
-  
+
   /// DeferredFunctionInfo - When function bodies are initially scanned, this
   /// map contains info about where to find deferred function body in the
   /// stream.
   DenseMap<Function*, uint64_t> DeferredFunctionInfo;
-  
+
   /// BlockAddrFwdRefs - These are blockaddr references to basic blocks.  These
   /// are resolved lazily when functions are loaded.
   typedef std::pair<unsigned, GlobalVariable*> BlockAddrRefTy;
   DenseMap<Function*, std::vector<BlockAddrRefTy> > BlockAddrFwdRefs;
 
+  /// UseRelativeIDs - Indicates that we are using a new encoding for
+  /// instruction operands where most operands in the current
+  /// FUNCTION_BLOCK are encoded relative to the instruction number,
+  /// for a more compact encoding.  Some instruction operands are not
+  /// relative to the instruction ID: basic block numbers, and types.
+  /// Once the old style function blocks have been phased out, we would
+  /// not need this flag.
+  bool UseRelativeIDs;
+
 public:
   explicit BitcodeReader(MemoryBuffer *buffer, LLVMContext &C)
     : Context(C), TheModule(0), Buffer(buffer), BufferOwned(false),
       LazyStreamer(0), NextUnreadBit(0), SeenValueSymbolTable(false),
       ErrorString(0), ValueList(C), MDValueList(C),
-      SeenFirstFunctionBody(false) {
+      SeenFirstFunctionBody(false), UseRelativeIDs(false) {
   }
   explicit BitcodeReader(DataStreamer *streamer, LLVMContext &C)
     : Context(C), TheModule(0), Buffer(0), BufferOwned(false),
       LazyStreamer(streamer), NextUnreadBit(0), SeenValueSymbolTable(false),
       ErrorString(0), ValueList(C), MDValueList(C),
-      SeenFirstFunctionBody(false) {
+      SeenFirstFunctionBody(false), UseRelativeIDs(false) {
   }
   ~BitcodeReader() {
     FreeState();
@@ -199,11 +211,11 @@ public:
   void materializeForwardReferencedFunctions();
 
   void FreeState();
-  
+
   /// setBufferOwned - If this is true, the reader will destroy the MemoryBuffer
   /// when the reader is destroyed.
   void setBufferOwned(bool Owned) { BufferOwned = Owned; }
-  
+
   virtual bool isMaterializable(const GlobalValue *GV) const;
   virtual bool isDematerializable(const GlobalValue *GV) const;
   virtual bool Materialize(GlobalValue *GV, std::string *ErrInfo = 0);
@@ -215,7 +227,7 @@ public:
     return true;
   }
   const char *getErrorString() const { return ErrorString; }
-  
+
   /// @brief Main interface to parsing a bitcode buffer.
   /// @returns true if an error occurred.
   bool ParseBitcodeInto(Module *M);
@@ -223,6 +235,9 @@ public:
   /// @brief Cheap mechanism to just extract module triple
   /// @returns true if an error occurred.
   bool ParseTriple(std::string &Triple);
+
+  static uint64_t decodeSignRotatedValue(uint64_t V);
+
 private:
   Type *getTypeByID(unsigned ID);
   Value *getFnValueByID(unsigned ID, Type *Ty) {
@@ -234,12 +249,12 @@ private:
     if (ID >= FunctionBBs.size()) return 0; // Invalid ID
     return FunctionBBs[ID];
   }
-  AttrListPtr getAttributes(unsigned i) const {
+  AttributeSet getAttributes(unsigned i) const {
     if (i-1 < MAttributes.size())
       return MAttributes[i-1];
-    return AttrListPtr();
+    return AttributeSet();
   }
-  
+
   /// getValueTypePair - Read a value/type pair out of the specified record from
   /// slot 'Slot'.  Increment Slot past the number of slots used in the record.
   /// Return true on failure.
@@ -247,6 +262,9 @@ private:
                         unsigned InstNum, Value *&ResVal) {
     if (Slot == Record.size()) return true;
     unsigned ValNo = (unsigned)Record[Slot++];
+    // Adjust the ValNo, if it was encoded relative to the InstNum.
+    if (UseRelativeIDs)
+      ValNo = InstNum - ValNo;
     if (ValNo < InstNum) {
       // If this is not a forward reference, just return the value we already
       // have.
@@ -255,22 +273,57 @@ private:
     } else if (Slot == Record.size()) {
       return true;
     }
-    
+
     unsigned TypeNo = (unsigned)Record[Slot++];
     ResVal = getFnValueByID(ValNo, getTypeByID(TypeNo));
     return ResVal == 0;
   }
-  bool getValue(SmallVector<uint64_t, 64> &Record, unsigned &Slot,
-                Type *Ty, Value *&ResVal) {
-    if (Slot == Record.size()) return true;
-    unsigned ValNo = (unsigned)Record[Slot++];
-    ResVal = getFnValueByID(ValNo, Ty);
+
+  /// popValue - Read a value out of the specified record from slot 'Slot'.
+  /// Increment Slot past the number of slots used by the value in the record.
+  /// Return true if there is an error.
+  bool popValue(SmallVector<uint64_t, 64> &Record, unsigned &Slot,
+                unsigned InstNum, Type *Ty, Value *&ResVal) {
+    if (getValue(Record, Slot, InstNum, Ty, ResVal))
+      return true;
+    // All values currently take a single record slot.
+    ++Slot;
+    return false;
+  }
+
+  /// getValue -- Like popValue, but does not increment the Slot number.
+  bool getValue(SmallVector<uint64_t, 64> &Record, unsigned Slot,
+                unsigned InstNum, Type *Ty, Value *&ResVal) {
+    ResVal = getValue(Record, Slot, InstNum, Ty);
     return ResVal == 0;
   }
 
-  
+  /// getValue -- Version of getValue that returns ResVal directly,
+  /// or 0 if there is an error.
+  Value *getValue(SmallVector<uint64_t, 64> &Record, unsigned Slot,
+                  unsigned InstNum, Type *Ty) {
+    if (Slot == Record.size()) return 0;
+    unsigned ValNo = (unsigned)Record[Slot];
+    // Adjust the ValNo, if it was encoded relative to the InstNum.
+    if (UseRelativeIDs)
+      ValNo = InstNum - ValNo;
+    return getFnValueByID(ValNo, Ty);
+  }
+
+  /// getValueSigned -- Like getValue, but decodes signed VBRs.
+  Value *getValueSigned(SmallVector<uint64_t, 64> &Record, unsigned Slot,
+                        unsigned InstNum, Type *Ty) {
+    if (Slot == Record.size()) return 0;
+    unsigned ValNo = (unsigned)decodeSignRotatedValue(Record[Slot]);
+    // Adjust the ValNo, if it was encoded relative to the InstNum.
+    if (UseRelativeIDs)
+      ValNo = InstNum - ValNo;
+    return getFnValueByID(ValNo, Ty);
+  }
+
   bool ParseModule(bool Resume);
   bool ParseAttributeBlock();
+  bool ParseAttributeGroupBlock();
   bool ParseTypeTable();
   bool ParseTypeTableBody();
 
@@ -290,7 +343,7 @@ private:
   bool FindFunctionInStream(Function *F,
          DenseMap<Function*, uint64_t>::iterator DeferredFunctionInfoIterator);
 };
-  
+
 } // End llvm namespace
 
 #endif