Add the clang library to the repo (with some of my changes, too).

1 files changed, 451 insertions, 0 deletions

diff --git a/clang/lib/CodeGen/CGValue.h b/clang/lib/CodeGen/CGValue.h
new file mode 100644
index 0000000..ac704e7
--- /dev/null
+++ b/clang/lib/CodeGen/CGValue.h
@@ -0,0 +1,451 @@
+//===-- CGValue.h - LLVM CodeGen wrappers for llvm::Value* ------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// These classes implement wrappers around llvm::Value in order to
+// fully represent the range of values for C L- and R- values.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef CLANG_CODEGEN_CGVALUE_H
+#define CLANG_CODEGEN_CGVALUE_H
+
+#include "clang/AST/ASTContext.h"
+#include "clang/AST/CharUnits.h"
+#include "clang/AST/Type.h"
+
+namespace llvm {
+  class Constant;
+  class Value;
+}
+
+namespace clang {
+namespace CodeGen {
+  class AggValueSlot;
+  class CGBitFieldInfo;
+
+/// RValue - This trivial value class is used to represent the result of an
+/// expression that is evaluated.  It can be one of three things: either a
+/// simple LLVM SSA value, a pair of SSA values for complex numbers, or the
+/// address of an aggregate value in memory.
+class RValue {
+  enum Flavor { Scalar, Complex, Aggregate };
+
+  // Stores first value and flavor.
+  llvm::PointerIntPair<llvm::Value *, 2, Flavor> V1;
+  // Stores second value and volatility.
+  llvm::PointerIntPair<llvm::Value *, 1, bool> V2;
+
+public:
+  bool isScalar() const { return V1.getInt() == Scalar; }
+  bool isComplex() const { return V1.getInt() == Complex; }
+  bool isAggregate() const { return V1.getInt() == Aggregate; }
+
+  bool isVolatileQualified() const { return V2.getInt(); }
+
+  /// getScalarVal() - Return the Value* of this scalar value.
+  llvm::Value *getScalarVal() const {
+    assert(isScalar() && "Not a scalar!");
+    return V1.getPointer();
+  }
+
+  /// getComplexVal - Return the real/imag components of this complex value.
+  ///
+  std::pair<llvm::Value *, llvm::Value *> getComplexVal() const {
+    return std::make_pair(V1.getPointer(), V2.getPointer());
+  }
+
+  /// getAggregateAddr() - Return the Value* of the address of the aggregate.
+  llvm::Value *getAggregateAddr() const {
+    assert(isAggregate() && "Not an aggregate!");
+    return V1.getPointer();
+  }
+
+  static RValue get(llvm::Value *V) {
+    RValue ER;
+    ER.V1.setPointer(V);
+    ER.V1.setInt(Scalar);
+    ER.V2.setInt(false);
+    return ER;
+  }
+  static RValue getComplex(llvm::Value *V1, llvm::Value *V2) {
+    RValue ER;
+    ER.V1.setPointer(V1);
+    ER.V2.setPointer(V2);
+    ER.V1.setInt(Complex);
+    ER.V2.setInt(false);
+    return ER;
+  }
+  static RValue getComplex(const std::pair<llvm::Value *, llvm::Value *> &C) {
+    return getComplex(C.first, C.second);
+  }
+  // FIXME: Aggregate rvalues need to retain information about whether they are
+  // volatile or not.  Remove default to find all places that probably get this
+  // wrong.
+  static RValue getAggregate(llvm::Value *V, bool Volatile = false) {
+    RValue ER;
+    ER.V1.setPointer(V);
+    ER.V1.setInt(Aggregate);
+    ER.V2.setInt(Volatile);
+    return ER;
+  }
+};
+
+
+/// LValue - This represents an lvalue references.  Because C/C++ allow
+/// bitfields, this is not a simple LLVM pointer, it may be a pointer plus a
+/// bitrange.
+class LValue {
+  enum {
+    Simple,       // This is a normal l-value, use getAddress().
+    VectorElt,    // This is a vector element l-value (V[i]), use getVector*
+    BitField,     // This is a bitfield l-value, use getBitfield*.
+    ExtVectorElt  // This is an extended vector subset, use getExtVectorComp
+  } LVType;
+
+  llvm::Value *V;
+
+  union {
+    // Index into a vector subscript: V[i]
+    llvm::Value *VectorIdx;
+
+    // ExtVector element subset: V.xyx
+    llvm::Constant *VectorElts;
+
+    // BitField start bit and size
+    const CGBitFieldInfo *BitFieldInfo;
+  };
+
+  QualType Type;
+
+  // 'const' is unused here
+  Qualifiers Quals;
+
+  // The alignment to use when accessing this lvalue.  (For vector elements,
+  // this is the alignment of the whole vector.)
+  unsigned short Alignment;
+
+  // objective-c's ivar
+  bool Ivar:1;
+  
+  // objective-c's ivar is an array
+  bool ObjIsArray:1;
+
+  // LValue is non-gc'able for any reason, including being a parameter or local
+  // variable.
+  bool NonGC: 1;
+
+  // Lvalue is a global reference of an objective-c object
+  bool GlobalObjCRef : 1;
+  
+  // Lvalue is a thread local reference
+  bool ThreadLocalRef : 1;
+
+  Expr *BaseIvarExp;
+
+  /// TBAAInfo - TBAA information to attach to dereferences of this LValue.
+  llvm::MDNode *TBAAInfo;
+
+private:
+  void Initialize(QualType Type, Qualifiers Quals,
+                  CharUnits Alignment = CharUnits(),
+                  llvm::MDNode *TBAAInfo = 0) {
+    this->Type = Type;
+    this->Quals = Quals;
+    this->Alignment = Alignment.getQuantity();
+    assert(this->Alignment == Alignment.getQuantity() &&
+           "Alignment exceeds allowed max!");
+
+    // Initialize Objective-C flags.
+    this->Ivar = this->ObjIsArray = this->NonGC = this->GlobalObjCRef = false;
+    this->ThreadLocalRef = false;
+    this->BaseIvarExp = 0;
+    this->TBAAInfo = TBAAInfo;
+  }
+
+public:
+  bool isSimple() const { return LVType == Simple; }
+  bool isVectorElt() const { return LVType == VectorElt; }
+  bool isBitField() const { return LVType == BitField; }
+  bool isExtVectorElt() const { return LVType == ExtVectorElt; }
+
+  bool isVolatileQualified() const { return Quals.hasVolatile(); }
+  bool isRestrictQualified() const { return Quals.hasRestrict(); }
+  unsigned getVRQualifiers() const {
+    return Quals.getCVRQualifiers() & ~Qualifiers::Const;
+  }
+
+  QualType getType() const { return Type; }
+
+  Qualifiers::ObjCLifetime getObjCLifetime() const {
+    return Quals.getObjCLifetime();
+  }
+
+  bool isObjCIvar() const { return Ivar; }
+  void setObjCIvar(bool Value) { Ivar = Value; }
+
+  bool isObjCArray() const { return ObjIsArray; }
+  void setObjCArray(bool Value) { ObjIsArray = Value; }
+
+  bool isNonGC () const { return NonGC; }
+  void setNonGC(bool Value) { NonGC = Value; }
+
+  bool isGlobalObjCRef() const { return GlobalObjCRef; }
+  void setGlobalObjCRef(bool Value) { GlobalObjCRef = Value; }
+
+  bool isThreadLocalRef() const { return ThreadLocalRef; }
+  void setThreadLocalRef(bool Value) { ThreadLocalRef = Value;}
+
+  bool isObjCWeak() const {
+    return Quals.getObjCGCAttr() == Qualifiers::Weak;
+  }
+  bool isObjCStrong() const {
+    return Quals.getObjCGCAttr() == Qualifiers::Strong;
+  }
+
+  bool isVolatile() const {
+    return Quals.hasVolatile();
+  }
+  
+  Expr *getBaseIvarExp() const { return BaseIvarExp; }
+  void setBaseIvarExp(Expr *V) { BaseIvarExp = V; }
+
+  llvm::MDNode *getTBAAInfo() const { return TBAAInfo; }
+  void setTBAAInfo(llvm::MDNode *N) { TBAAInfo = N; }
+
+  const Qualifiers &getQuals() const { return Quals; }
+  Qualifiers &getQuals() { return Quals; }
+
+  unsigned getAddressSpace() const { return Quals.getAddressSpace(); }
+
+  CharUnits getAlignment() const { return CharUnits::fromQuantity(Alignment); }
+  void setAlignment(CharUnits A) { Alignment = A.getQuantity(); }
+
+  // simple lvalue
+  llvm::Value *getAddress() const { assert(isSimple()); return V; }
+  void setAddress(llvm::Value *address) {
+    assert(isSimple());
+    V = address;
+  }
+
+  // vector elt lvalue
+  llvm::Value *getVectorAddr() const { assert(isVectorElt()); return V; }
+  llvm::Value *getVectorIdx() const { assert(isVectorElt()); return VectorIdx; }
+
+  // extended vector elements.
+  llvm::Value *getExtVectorAddr() const { assert(isExtVectorElt()); return V; }
+  llvm::Constant *getExtVectorElts() const {
+    assert(isExtVectorElt());
+    return VectorElts;
+  }
+
+  // bitfield lvalue
+  llvm::Value *getBitFieldBaseAddr() const {
+    assert(isBitField());
+    return V;
+  }
+  const CGBitFieldInfo &getBitFieldInfo() const {
+    assert(isBitField());
+    return *BitFieldInfo;
+  }
+
+  static LValue MakeAddr(llvm::Value *address, QualType type,
+                         CharUnits alignment, ASTContext &Context,
+                         llvm::MDNode *TBAAInfo = 0) {
+    Qualifiers qs = type.getQualifiers();
+    qs.setObjCGCAttr(Context.getObjCGCAttrKind(type));
+
+    LValue R;
+    R.LVType = Simple;
+    R.V = address;
+    R.Initialize(type, qs, alignment, TBAAInfo);
+    return R;
+  }
+
+  static LValue MakeVectorElt(llvm::Value *Vec, llvm::Value *Idx,
+                              QualType type, CharUnits Alignment) {
+    LValue R;
+    R.LVType = VectorElt;
+    R.V = Vec;
+    R.VectorIdx = Idx;
+    R.Initialize(type, type.getQualifiers(), Alignment);
+    return R;
+  }
+
+  static LValue MakeExtVectorElt(llvm::Value *Vec, llvm::Constant *Elts,
+                                 QualType type, CharUnits Alignment) {
+    LValue R;
+    R.LVType = ExtVectorElt;
+    R.V = Vec;
+    R.VectorElts = Elts;
+    R.Initialize(type, type.getQualifiers(), Alignment);
+    return R;
+  }
+
+  /// \brief Create a new object to represent a bit-field access.
+  ///
+  /// \param BaseValue - The base address of the structure containing the
+  /// bit-field.
+  /// \param Info - The information describing how to perform the bit-field
+  /// access.
+  static LValue MakeBitfield(llvm::Value *BaseValue,
+                             const CGBitFieldInfo &Info,
+                             QualType type) {
+    LValue R;
+    R.LVType = BitField;
+    R.V = BaseValue;
+    R.BitFieldInfo = &Info;
+    R.Initialize(type, type.getQualifiers());
+    return R;
+  }
+
+  RValue asAggregateRValue() const {
+    // FIMXE: Alignment
+    return RValue::getAggregate(getAddress(), isVolatileQualified());
+  }
+};
+
+/// An aggregate value slot.
+class AggValueSlot {
+  /// The address.
+  llvm::Value *Addr;
+
+  // Qualifiers
+  Qualifiers Quals;
+
+  unsigned short Alignment;
+
+  /// DestructedFlag - This is set to true if some external code is
+  /// responsible for setting up a destructor for the slot.  Otherwise
+  /// the code which constructs it should push the appropriate cleanup.
+  bool DestructedFlag : 1;
+
+  /// ObjCGCFlag - This is set to true if writing to the memory in the
+  /// slot might require calling an appropriate Objective-C GC
+  /// barrier.  The exact interaction here is unnecessarily mysterious.
+  bool ObjCGCFlag : 1;
+  
+  /// ZeroedFlag - This is set to true if the memory in the slot is
+  /// known to be zero before the assignment into it.  This means that
+  /// zero fields don't need to be set.
+  bool ZeroedFlag : 1;
+
+  /// AliasedFlag - This is set to true if the slot might be aliased
+  /// and it's not undefined behavior to access it through such an
+  /// alias.  Note that it's always undefined behavior to access a C++
+  /// object that's under construction through an alias derived from
+  /// outside the construction process.
+  ///
+  /// This flag controls whether calls that produce the aggregate
+  /// value may be evaluated directly into the slot, or whether they
+  /// must be evaluated into an unaliased temporary and then memcpy'ed
+  /// over.  Since it's invalid in general to memcpy a non-POD C++
+  /// object, it's important that this flag never be set when
+  /// evaluating an expression which constructs such an object.
+  bool AliasedFlag : 1;
+
+public:
+  enum IsAliased_t { IsNotAliased, IsAliased };
+  enum IsDestructed_t { IsNotDestructed, IsDestructed };
+  enum IsZeroed_t { IsNotZeroed, IsZeroed };
+  enum NeedsGCBarriers_t { DoesNotNeedGCBarriers, NeedsGCBarriers };
+
+  /// ignored - Returns an aggregate value slot indicating that the
+  /// aggregate value is being ignored.
+  static AggValueSlot ignored() {
+    return forAddr(0, CharUnits(), Qualifiers(), IsNotDestructed,
+                   DoesNotNeedGCBarriers, IsNotAliased);
+  }
+
+  /// forAddr - Make a slot for an aggregate value.
+  ///
+  /// \param quals - The qualifiers that dictate how the slot should
+  /// be initialied. Only 'volatile' and the Objective-C lifetime
+  /// qualifiers matter.
+  ///
+  /// \param isDestructed - true if something else is responsible
+  ///   for calling destructors on this object
+  /// \param needsGC - true if the slot is potentially located
+  ///   somewhere that ObjC GC calls should be emitted for
+  static AggValueSlot forAddr(llvm::Value *addr, CharUnits align,
+                              Qualifiers quals,
+                              IsDestructed_t isDestructed,
+                              NeedsGCBarriers_t needsGC,
+                              IsAliased_t isAliased,
+                              IsZeroed_t isZeroed = IsNotZeroed) {
+    AggValueSlot AV;
+    AV.Addr = addr;
+    AV.Alignment = align.getQuantity();
+    AV.Quals = quals;
+    AV.DestructedFlag = isDestructed;
+    AV.ObjCGCFlag = needsGC;
+    AV.ZeroedFlag = isZeroed;
+    AV.AliasedFlag = isAliased;
+    return AV;
+  }
+
+  static AggValueSlot forLValue(LValue LV, IsDestructed_t isDestructed,
+                                NeedsGCBarriers_t needsGC,
+                                IsAliased_t isAliased,
+                                IsZeroed_t isZeroed = IsNotZeroed) {
+    return forAddr(LV.getAddress(), LV.getAlignment(),
+                   LV.getQuals(), isDestructed, needsGC, isAliased, isZeroed);
+  }
+
+  IsDestructed_t isExternallyDestructed() const {
+    return IsDestructed_t(DestructedFlag);
+  }
+  void setExternallyDestructed(bool destructed = true) {
+    DestructedFlag = destructed;
+  }
+
+  Qualifiers getQualifiers() const { return Quals; }
+
+  bool isVolatile() const {
+    return Quals.hasVolatile();
+  }
+
+  Qualifiers::ObjCLifetime getObjCLifetime() const {
+    return Quals.getObjCLifetime();
+  }
+
+  NeedsGCBarriers_t requiresGCollection() const {
+    return NeedsGCBarriers_t(ObjCGCFlag);
+  }
+  
+  llvm::Value *getAddr() const {
+    return Addr;
+  }
+
+  bool isIgnored() const {
+    return Addr == 0;
+  }
+
+  CharUnits getAlignment() const {
+    return CharUnits::fromQuantity(Alignment);
+  }
+
+  IsAliased_t isPotentiallyAliased() const {
+    return IsAliased_t(AliasedFlag);
+  }
+
+  // FIXME: Alignment?
+  RValue asRValue() const {
+    return RValue::getAggregate(getAddr(), isVolatile());
+  }
+
+  void setZeroed(bool V = true) { ZeroedFlag = V; }
+  IsZeroed_t isZeroed() const {
+    return IsZeroed_t(ZeroedFlag);
+  }
+};
+
+}  // end namespace CodeGen
+}  // end namespace clang
+
+#endif