Add addrspacecast instruction.

Patch by Michele Scandale!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194760 91177308-0d34-0410-b5e6-96231b3b80d8

51 files changed, 588 insertions, 229 deletions

diff --git a/docs/LangRef.rst b/docs/LangRef.rst
index 9c033ed..58bba1b 100644
--- a/docs/LangRef.rst
+++ b/docs/LangRef.rst
@@ -2382,6 +2382,10 @@ The following is the syntax for constant expressions:
     Convert a constant, CST, to another TYPE. The constraints of the
     operands are the same as those for the :ref:`bitcast
     instruction <i_bitcast>`.
+``addrspacecast (CST to TYPE)``
+    Convert a constant pointer or constant vector of pointer, CST, to another
+    TYPE in a different address space. The constraints of the operands are the
+    same as those for the :ref:`addrspacecast instruction <i_addrspacecast>`.
 ``getelementptr (CSTPTR, IDX0, IDX1, ...)``, ``getelementptr inbounds (CSTPTR, IDX0, IDX1, ...)``
     Perform the :ref:`getelementptr operation <i_getelementptr>` on
     constants. As with the :ref:`getelementptr <i_getelementptr>`
@@ -5726,9 +5730,9 @@ is always a *no-op cast* because no bits change with this
 conversion. The conversion is done as if the ``value`` had been stored
 to memory and read back as type ``ty2``. Pointer (or vector of
 pointers) types may only be converted to other pointer (or vector of
-pointers) types with this instruction if the pointer sizes are
-equal. To convert pointers to other types, use the :ref:`inttoptr
-<i_inttoptr>` or :ref:`ptrtoint <i_ptrtoint>` instructions first.
+pointers) types with the same address space through this instruction.
+To convert pointers to other types, use the :ref:`inttoptr <i_inttoptr>`
+or :ref:`ptrtoint <i_ptrtoint>` instructions first.
 
 Example:
 """"""""
@@ -5740,6 +5744,51 @@ Example:
       %Z = bitcast <2 x int> %V to i64;        ; yields i64: %V
       %Z = bitcast <2 x i32*> %V to <2 x i64*> ; yields <2 x i64*>
 
+.. _i_addrspacecast:
+
+'``addrspacecast .. to``' Instruction
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Syntax:
+"""""""
+
+::
+
+      <result> = addrspacecast <pty> <ptrval> to <pty2>       ; yields pty2
+
+Overview:
+"""""""""
+
+The '``addrspacecast``' instruction converts ``ptrval`` from ``pty`` in
+address space ``n`` to type ``pty2`` in address space ``m``.
+
+Arguments:
+""""""""""
+
+The '``addrspacecast``' instruction takes a pointer or vector of pointer value
+to cast and a pointer type to cast it to, which must have a different
+address space.
+
+Semantics:
+""""""""""
+
+The '``addrspacecast``' instruction converts the pointer value
+``ptrval`` to type ``pty2``. It can be a *no-op cast* or a complex
+value modification, depending on the target and the address spaces
+pair. Pointers conversion within the same address space must be
+performed with ``bitcast`` instruction. Note that if the address space
+conversion is legal then both result and operand refer to the same memory
+location.
+
+Example:
+""""""""
+
+.. code-block:: llvm
+
+      %X = addrspacecast i32* %x to addrspace(1) i32*    ; yields addrspace(1) i32*:%x
+      %Y = addrspacecast addrspace(1) <2 x i32>* %y to addrspace(2) i64*    ; yields addrspace(2) i32*:%y
+      %Z = addrspacecast <4 x i32*> %z to <4 x float addrspace(3)*>    ; yelds <4 x float addrspace(3)*>:%z
+
 .. _otherops:
 
 Other Operations
diff --git a/include/llvm-c/Core.h b/include/llvm-c/Core.h
index d4de523..9953d52 100644
--- a/include/llvm-c/Core.h
+++ b/include/llvm-c/Core.h
@@ -222,6 +222,7 @@ typedef enum {
   LLVMPtrToInt       = 39,
   LLVMIntToPtr       = 40,
   LLVMBitCast        = 41,
+  LLVMAddrSpaceCast  = 60,
 
   /* Other Operators */
   LLVMICmp           = 42,
@@ -1159,6 +1160,7 @@ LLVMTypeRef LLVMX86MMXType(void);
       macro(UnaryInstruction)               \
         macro(AllocaInst)                   \
         macro(CastInst)                     \
+          macro(AddrSpaceCastInst)          \
           macro(BitCastInst)                \
           macro(FPExtInst)                  \
           macro(FPToSIInst)                 \
@@ -1630,6 +1632,7 @@ LLVMValueRef LLVMConstFPToSI(LLVMValueRef ConstantVal, LLVMTypeRef ToType);
 LLVMValueRef LLVMConstPtrToInt(LLVMValueRef ConstantVal, LLVMTypeRef ToType);
 LLVMValueRef LLVMConstIntToPtr(LLVMValueRef ConstantVal, LLVMTypeRef ToType);
 LLVMValueRef LLVMConstBitCast(LLVMValueRef ConstantVal, LLVMTypeRef ToType);
+LLVMValueRef LLVMConstAddrSpaceCast(LLVMValueRef ConstantVal, LLVMTypeRef ToType);
 LLVMValueRef LLVMConstZExtOrBitCast(LLVMValueRef ConstantVal,
                                     LLVMTypeRef ToType);
 LLVMValueRef LLVMConstSExtOrBitCast(LLVMValueRef ConstantVal,
@@ -2605,6 +2608,8 @@ LLVMValueRef LLVMBuildIntToPtr(LLVMBuilderRef, LLVMValueRef Val,
                                LLVMTypeRef DestTy, const char *Name);
 LLVMValueRef LLVMBuildBitCast(LLVMBuilderRef, LLVMValueRef Val,
                               LLVMTypeRef DestTy, const char *Name);
+LLVMValueRef LLVMBuildAddrSpaceCast(LLVMBuilderRef, LLVMValueRef Val,
+                                    LLVMTypeRef DestTy, const char *Name);
 LLVMValueRef LLVMBuildZExtOrBitCast(LLVMBuilderRef, LLVMValueRef Val,
                                     LLVMTypeRef DestTy, const char *Name);
 LLVMValueRef LLVMBuildSExtOrBitCast(LLVMBuilderRef, LLVMValueRef Val,
diff --git a/include/llvm/AutoUpgrade.h b/include/llvm/AutoUpgrade.h
index 8df87fa..22d0c43 100644
--- a/include/llvm/AutoUpgrade.h
+++ b/include/llvm/AutoUpgrade.h
@@ -15,11 +15,14 @@
 #define LLVM_AUTOUPGRADE_H
 
 namespace llvm {
+  class Constant;
   class Module;
   class GlobalVariable;
   class Function;
   class CallInst;
   class Instruction;
+  class Value;
+  class Type;
 
   /// This is a more granular function that simply checks an intrinsic function
   /// for upgrading, and returns true if it requires upgrading. It may return
@@ -44,6 +47,16 @@ namespace llvm {
   /// If the TBAA tag for the given instruction uses the scalar TBAA format,
   /// we upgrade it to the struct-path aware TBAA format.
   void UpgradeInstWithTBAATag(Instruction *I);
+
+  /// This is an auto-upgrade for bitcast between pointers with different
+  /// address spaces: the instruction is replaced by a pair ptrtoint+inttoptr.
+  Instruction *UpgradeBitCastInst(unsigned Opc, Value *V, Type *DestTy,
+                                  Instruction *&Temp);
+
+  /// This is an auto-upgrade for bitcast constant expression between pointers
+  /// with different address spaces: the instruction is replaced by a pair
+  /// ptrtoint+inttoptr.
+  Value *UpgradeBitCastExpr(unsigned Opc, Constant *C, Type *DestTy);
 } // End llvm namespace
 
 #endif
diff --git a/include/llvm/Bitcode/LLVMBitCodes.h b/include/llvm/Bitcode/LLVMBitCodes.h
index 90e9063..b3d2466 100644
--- a/include/llvm/Bitcode/LLVMBitCodes.h
+++ b/include/llvm/Bitcode/LLVMBitCodes.h
@@ -194,7 +194,8 @@ namespace bitc {
     CAST_FPEXT    =  8,
     CAST_PTRTOINT =  9,
     CAST_INTTOPTR = 10,
-    CAST_BITCAST  = 11
+    CAST_BITCAST  = 11,
+    CAST_ADDRSPACECAST = 12
   };
 
   /// BinaryOpcodes - These are values used in the bitcode files to encode which
diff --git a/include/llvm/CodeGen/ISDOpcodes.h b/include/llvm/CodeGen/ISDOpcodes.h
index 3a49dd8..48a0523 100644
--- a/include/llvm/CodeGen/ISDOpcodes.h
+++ b/include/llvm/CodeGen/ISDOpcodes.h
@@ -419,6 +419,10 @@ namespace ISD {
     /// getNode().
     BITCAST,
 
+    /// ADDRSPACECAST - This operator converts between pointers of different
+    /// address spaces.
+    ADDRSPACECAST,
+
     /// CONVERT_RNDSAT - This operator is used to support various conversions
     /// between various types (float, signed, unsigned and vectors of those
     /// types) with rounding and saturation. NOTE: Avoid using this operator as
diff --git a/include/llvm/CodeGen/SelectionDAG.h b/include/llvm/CodeGen/SelectionDAG.h
index 3f27bce..5f18c4e 100644
--- a/include/llvm/CodeGen/SelectionDAG.h
+++ b/include/llvm/CodeGen/SelectionDAG.h
@@ -802,6 +802,10 @@ public:
   /// getMDNode - Return an MDNodeSDNode which holds an MDNode.
   SDValue getMDNode(const MDNode *MD);
 
+  /// getAddrSpaceCast - Return an AddrSpaceCastSDNode.
+  SDValue getAddrSpaceCast(SDLoc dl, EVT VT, SDValue Ptr,
+                           unsigned SrcAS, unsigned DestAS);
+
   /// getShiftAmountOperand - Return the specified value casted to
   /// the target's desired shift amount type.
   SDValue getShiftAmountOperand(EVT LHSTy, SDValue Op);
diff --git a/include/llvm/CodeGen/SelectionDAGNodes.h b/include/llvm/CodeGen/SelectionDAGNodes.h
index 8ec3b09..70c15e6 100644
--- a/include/llvm/CodeGen/SelectionDAGNodes.h
+++ b/include/llvm/CodeGen/SelectionDAGNodes.h
@@ -950,6 +950,23 @@ public:
   const SDValue &getValue() const { return Op; }
 };
 
+class AddrSpaceCastSDNode : public UnarySDNode {
+private:
+  unsigned SrcAddrSpace;
+  unsigned DestAddrSpace;
+
+public:
+  AddrSpaceCastSDNode(unsigned Order, DebugLoc dl, EVT VT, SDValue X,
+                      unsigned SrcAS, unsigned DestAS);
+
+  unsigned getSrcAddressSpace() const { return SrcAddrSpace; }
+  unsigned getDestAddressSpace() const { return DestAddrSpace; }
+
+  static bool classof(const SDNode *N) {
+    return N->getOpcode() == ISD::ADDRSPACECAST;
+  }
+};
+
 /// Abstact virtual class for operations for memory operations
 class MemSDNode : public SDNode {
 private:
diff --git a/include/llvm/IR/Constants.h b/include/llvm/IR/Constants.h
index 99aed0d..b6e2082 100644
--- a/include/llvm/IR/Constants.h
+++ b/include/llvm/IR/Constants.h
@@ -862,6 +862,7 @@ public:
   static Constant *getPtrToInt(Constant *C, Type *Ty);
   static Constant *getIntToPtr(Constant *C, Type *Ty);
   static Constant *getBitCast (Constant *C, Type *Ty);
+  static Constant *getAddrSpaceCast (Constant *C, Type *Ty);
 
   static Constant *getNSWNeg(Constant *C) { return getNeg(C, false, true); }
   static Constant *getNUWNeg(Constant *C) { return getNeg(C, true, false); }
diff --git a/include/llvm/IR/IRBuilder.h b/include/llvm/IR/IRBuilder.h
index e2aeed3..8d1432d 100644
--- a/include/llvm/IR/IRBuilder.h
+++ b/include/llvm/IR/IRBuilder.h
@@ -1133,6 +1133,10 @@ public:
                        const Twine &Name = "") {
     return CreateCast(Instruction::BitCast, V, DestTy, Name);
   }
+  Value *CreateAddrSpaceCast(Value *V, Type *DestTy,
+                             const Twine &Name = "") {
+    return CreateCast(Instruction::AddrSpaceCast, V, DestTy, Name);
+  }
   Value *CreateZExtOrBitCast(Value *V, Type *DestTy,
                              const Twine &Name = "") {
     if (V->getType() == DestTy)
diff --git a/include/llvm/IR/Instruction.def b/include/llvm/IR/Instruction.def
index e59a052..d46314c 100644
--- a/include/llvm/IR/Instruction.def
+++ b/include/llvm/IR/Instruction.def
@@ -154,25 +154,26 @@ HANDLE_CAST_INST(41, FPExt   , FPExtInst   )  // Extend floating point
 HANDLE_CAST_INST(42, PtrToInt, PtrToIntInst)  // Pointer -> Integer
 HANDLE_CAST_INST(43, IntToPtr, IntToPtrInst)  // Integer -> Pointer
 HANDLE_CAST_INST(44, BitCast , BitCastInst )  // Type cast
-  LAST_CAST_INST(44)
+HANDLE_CAST_INST(45, AddrSpaceCast, AddrSpaceCastInst)  // addrspace cast
+  LAST_CAST_INST(45)
 
 // Other operators...
- FIRST_OTHER_INST(45)
-HANDLE_OTHER_INST(45, ICmp   , ICmpInst   )  // Integer comparison instruction
-HANDLE_OTHER_INST(46, FCmp   , FCmpInst   )  // Floating point comparison instr.
-HANDLE_OTHER_INST(47, PHI    , PHINode    )  // PHI node instruction
-HANDLE_OTHER_INST(48, Call   , CallInst   )  // Call a function
-HANDLE_OTHER_INST(49, Select , SelectInst )  // select instruction
-HANDLE_OTHER_INST(50, UserOp1, Instruction)  // May be used internally in a pass
-HANDLE_OTHER_INST(51, UserOp2, Instruction)  // Internal to passes only
-HANDLE_OTHER_INST(52, VAArg  , VAArgInst  )  // vaarg instruction
-HANDLE_OTHER_INST(53, ExtractElement, ExtractElementInst)// extract from vector
-HANDLE_OTHER_INST(54, InsertElement, InsertElementInst)  // insert into vector
-HANDLE_OTHER_INST(55, ShuffleVector, ShuffleVectorInst)  // shuffle two vectors.
-HANDLE_OTHER_INST(56, ExtractValue, ExtractValueInst)// extract from aggregate
-HANDLE_OTHER_INST(57, InsertValue, InsertValueInst)  // insert into aggregate
-HANDLE_OTHER_INST(58, LandingPad, LandingPadInst)  // Landing pad instruction.
-  LAST_OTHER_INST(58)
+ FIRST_OTHER_INST(46)
+HANDLE_OTHER_INST(46, ICmp   , ICmpInst   )  // Integer comparison instruction
+HANDLE_OTHER_INST(47, FCmp   , FCmpInst   )  // Floating point comparison instr.
+HANDLE_OTHER_INST(48, PHI    , PHINode    )  // PHI node instruction
+HANDLE_OTHER_INST(49, Call   , CallInst   )  // Call a function
+HANDLE_OTHER_INST(50, Select , SelectInst )  // select instruction
+HANDLE_OTHER_INST(51, UserOp1, Instruction)  // May be used internally in a pass
+HANDLE_OTHER_INST(52, UserOp2, Instruction)  // Internal to passes only
+HANDLE_OTHER_INST(53, VAArg  , VAArgInst  )  // vaarg instruction
+HANDLE_OTHER_INST(54, ExtractElement, ExtractElementInst)// extract from vector
+HANDLE_OTHER_INST(55, InsertElement, InsertElementInst)  // insert into vector
+HANDLE_OTHER_INST(56, ShuffleVector, ShuffleVectorInst)  // shuffle two vectors.
+HANDLE_OTHER_INST(57, ExtractValue, ExtractValueInst)// extract from aggregate
+HANDLE_OTHER_INST(58, InsertValue, InsertValueInst)  // insert into aggregate
+HANDLE_OTHER_INST(59, LandingPad, LandingPadInst)  // Landing pad instruction.
+  LAST_OTHER_INST(59)
 
 #undef  FIRST_TERM_INST
 #undef HANDLE_TERM_INST
diff --git a/include/llvm/IR/Instructions.h b/include/llvm/IR/Instructions.h
index da260fb..0843d8f 100644
--- a/include/llvm/IR/Instructions.h
+++ b/include/llvm/IR/Instructions.h
@@ -3615,6 +3615,43 @@ public:
   }
 };
 
+//===----------------------------------------------------------------------===//
+//                          AddrSpaceCastInst Class
+//===----------------------------------------------------------------------===//
+
+/// \brief This class represents a conversion between pointers from
+/// one address space to another.
+class AddrSpaceCastInst : public CastInst {
+protected:
+  /// \brief Clone an identical AddrSpaceCastInst
+  virtual AddrSpaceCastInst *clone_impl() const;
+
+public:
+  /// \brief Constructor with insert-before-instruction semantics
+  AddrSpaceCastInst(
+    Value *S,                     ///< The value to be casted
+    Type *Ty,                     ///< The type to casted to
+    const Twine &NameStr = "",    ///< A name for the new instruction
+    Instruction *InsertBefore = 0 ///< Where to insert the new instruction
+  );
+
+  /// \brief Constructor with insert-at-end-of-block semantics
+  AddrSpaceCastInst(
+    Value *S,                     ///< The value to be casted
+    Type *Ty,                     ///< The type to casted to
+    const Twine &NameStr,         ///< A name for the new instruction
+    BasicBlock *InsertAtEnd       ///< The block to insert the instruction into
+  );
+
+  // Methods for support type inquiry through isa, cast, and dyn_cast:
+  static inline bool classof(const Instruction *I) {
+    return I->getOpcode() == AddrSpaceCast;
+  }
+  static inline bool classof(const Value *V) {
+    return isa<Instruction>(V) && classof(cast<Instruction>(V));
+  }
+};
+
 } // End llvm namespace
 
 #endif
diff --git a/include/llvm/InstVisitor.h b/include/llvm/InstVisitor.h
index 2911703..de7206d 100644
--- a/include/llvm/InstVisitor.h
+++ b/include/llvm/InstVisitor.h
@@ -191,6 +191,7 @@ public:
   RetTy visitPtrToIntInst(PtrToIntInst &I)        { DELEGATE(CastInst);}
   RetTy visitIntToPtrInst(IntToPtrInst &I)        { DELEGATE(CastInst);}
   RetTy visitBitCastInst(BitCastInst &I)          { DELEGATE(CastInst);}
+  RetTy visitAddrSpaceCastInst(AddrSpaceCastInst &I) { DELEGATE(CastInst);}
   RetTy visitSelectInst(SelectInst &I)            { DELEGATE(Instruction);}
   RetTy visitVAArgInst(VAArgInst   &I)            { DELEGATE(UnaryInstruction);}
   RetTy visitExtractElementInst(ExtractElementInst &I) { DELEGATE(Instruction);}
diff --git a/include/llvm/Target/TargetLowering.h b/include/llvm/Target/TargetLowering.h
index 5d6d1d2..2649d26 100644
--- a/include/llvm/Target/TargetLowering.h
+++ b/include/llvm/Target/TargetLowering.h
@@ -827,6 +827,11 @@ public:
     return 0;
   }
 
+  /// Returns true if a cast between SrcAS and DestAS is a noop.
+  virtual bool isNoopAddrSpaceCast(unsigned SrcAS, unsigned DestAS) const {
+    return false;
+  }
+
   //===--------------------------------------------------------------------===//
   /// \name Helpers for TargetTransformInfo implementations
   /// @{
diff --git a/lib/Analysis/ConstantFolding.cpp b/lib/Analysis/ConstantFolding.cpp
index e093631..3d32232 100644
--- a/lib/Analysis/ConstantFolding.cpp
+++ b/lib/Analysis/ConstantFolding.cpp
@@ -663,7 +663,7 @@ static Constant* StripPtrCastKeepAS(Constant* Ptr) {
   if (NewPtrTy->getAddressSpace() != OldPtrTy->getAddressSpace()) {
     NewPtrTy = NewPtrTy->getElementType()->getPointerTo(
       OldPtrTy->getAddressSpace());
-    Ptr = ConstantExpr::getBitCast(Ptr, NewPtrTy);
+    Ptr = ConstantExpr::getPointerCast(Ptr, NewPtrTy);
   }
   return Ptr;
 }
@@ -995,8 +995,9 @@ Constant *llvm::ConstantFoldInstOperands(unsigned Opcode, Type *DestTy,
     return ConstantExpr::getCast(Opcode, Ops[0], DestTy);
   case Instruction::IntToPtr:
     // If the input is a ptrtoint, turn the pair into a ptr to ptr bitcast if
-    // the int size is >= the ptr size.  This requires knowing the width of a
-    // pointer, so it can't be done in ConstantExpr::getCast.
+    // the int size is >= the ptr size and the address spaces are the same.
+    // This requires knowing the width of a pointer, so it can't be done in
+    // ConstantExpr::getCast.
     if (ConstantExpr *CE = dyn_cast<ConstantExpr>(Ops[0])) {
       if (TD && CE->getOpcode() == Instruction::PtrToInt) {
         Constant *SrcPtr = CE->getOperand(0);
@@ -1004,8 +1005,8 @@ Constant *llvm::ConstantFoldInstOperands(unsigned Opcode, Type *DestTy,
         unsigned MidIntSize = CE->getType()->getScalarSizeInBits();
 
         if (MidIntSize >= SrcPtrSize) {
-          unsigned DestPtrSize = TD->getPointerTypeSizeInBits(DestTy);
-          if (SrcPtrSize == DestPtrSize)
+          unsigned SrcAS = SrcPtr->getType()->getPointerAddressSpace();
+          if (SrcAS == DestTy->getPointerAddressSpace())
             return FoldBitCast(CE->getOperand(0), DestTy, *TD);
         }
       }
@@ -1021,6 +1022,7 @@ Constant *llvm::ConstantFoldInstOperands(unsigned Opcode, Type *DestTy,
   case Instruction::SIToFP:
   case Instruction::FPToUI:
   case Instruction::FPToSI:
+  case Instruction::AddrSpaceCast:
       return ConstantExpr::getCast(Opcode, Ops[0], DestTy);
   case Instruction::BitCast:
     if (TD)
diff --git a/lib/AsmParser/LLLexer.cpp b/lib/AsmParser/LLLexer.cpp
index 4c9439a..1e6085b 100644
--- a/lib/AsmParser/LLLexer.cpp
+++ b/lib/AsmParser/LLLexer.cpp
@@ -665,6 +665,7 @@ lltok::Kind LLLexer::LexIdentifier() {
   INSTKEYWORD(inttoptr,    IntToPtr);
   INSTKEYWORD(ptrtoint,    PtrToInt);
   INSTKEYWORD(bitcast,     BitCast);
+  INSTKEYWORD(addrspacecast, AddrSpaceCast);
   INSTKEYWORD(select,      Select);
   INSTKEYWORD(va_arg,      VAArg);
   INSTKEYWORD(ret,         Ret);
diff --git a/lib/AsmParser/LLParser.cpp b/lib/AsmParser/LLParser.cpp
index ad2cbe3..20fa0f4 100644
--- a/lib/AsmParser/LLParser.cpp
+++ b/lib/AsmParser/LLParser.cpp
@@ -2415,6 +2415,7 @@ bool LLParser::ParseValID(ValID &ID, PerFunctionState *PFS) {
   case lltok::kw_fptrunc:
   case lltok::kw_fpext:
   case lltok::kw_bitcast:
+  case lltok::kw_addrspacecast:
   case lltok::kw_uitofp:
   case lltok::kw_sitofp:
   case lltok::kw_fptoui:
@@ -3303,6 +3304,7 @@ int LLParser::ParseInstruction(Instruction *&Inst, BasicBlock *BB,
   case lltok::kw_fptrunc:
   case lltok::kw_fpext:
   case lltok::kw_bitcast:
+  case lltok::kw_addrspacecast:
   case lltok::kw_uitofp:
   case lltok::kw_sitofp:
   case lltok::kw_fptoui:
diff --git a/lib/AsmParser/LLToken.h b/lib/AsmParser/LLToken.h
index 086ea95..786d84d 100644
--- a/lib/AsmParser/LLToken.h
+++ b/lib/AsmParser/LLToken.h
@@ -150,6 +150,7 @@ namespace lltok {
     kw_phi, kw_call,
     kw_trunc, kw_zext, kw_sext, kw_fptrunc, kw_fpext, kw_uitofp, kw_sitofp,
     kw_fptoui, kw_fptosi, kw_inttoptr, kw_ptrtoint, kw_bitcast,
+    kw_addrspacecast,
     kw_select, kw_va_arg,
 
     kw_landingpad, kw_personality, kw_cleanup, kw_catch, kw_filter,
diff --git a/lib/Bitcode/Reader/BitcodeReader.cpp b/lib/Bitcode/Reader/BitcodeReader.cpp
index d25b33e..e052e6e 100644
--- a/lib/Bitcode/Reader/BitcodeReader.cpp
+++ b/lib/Bitcode/Reader/BitcodeReader.cpp
@@ -128,6 +128,7 @@ static int GetDecodedCastOpcode(unsigned Val) {
   case bitc::CAST_PTRTOINT: return Instruction::PtrToInt;
   case bitc::CAST_INTTOPTR: return Instruction::IntToPtr;
   case bitc::CAST_BITCAST : return Instruction::BitCast;
+  case bitc::CAST_ADDRSPACECAST : return Instruction::AddrSpaceCast;
   }
 }
 static int GetDecodedBinaryOpcode(unsigned Val, Type *Ty) {
@@ -1356,7 +1357,8 @@ error_code BitcodeReader::ParseConstants() {
         if (!OpTy)
           return Error(InvalidRecord);
         Constant *Op = ValueList.getConstantFwdRef(Record[2], OpTy);
-        V = ConstantExpr::getCast(Opc, Op, CurTy);
+        V = UpgradeBitCastExpr(Opc, Op, CurTy);
+        if (!V) V = ConstantExpr::getCast(Opc, Op, CurTy);
       }
       break;
     }
@@ -2296,7 +2298,15 @@ error_code BitcodeReader::ParseFunctionBody(Function *F) {
       int Opc = GetDecodedCastOpcode(Record[OpNum+1]);
       if (Opc == -1 || ResTy == 0)
         return Error(InvalidRecord);
-      I = CastInst::Create((Instruction::CastOps)Opc, Op, ResTy);
+      Instruction *Temp = 0;
+      if ((I = UpgradeBitCastInst(Opc, Op, ResTy, Temp))) {
+        if (Temp) {
+          InstructionList.push_back(Temp);
+          CurBB->getInstList().push_back(Temp);
+        }
+      } else {
+        I = CastInst::Create((Instruction::CastOps)Opc, Op, ResTy);
+      }
       InstructionList.push_back(I);
       break;
     }
diff --git a/lib/Bitcode/Writer/BitcodeWriter.cpp b/lib/Bitcode/Writer/BitcodeWriter.cpp
index 6f7aa14..02ee917 100644
--- a/lib/Bitcode/Writer/BitcodeWriter.cpp
+++ b/lib/Bitcode/Writer/BitcodeWriter.cpp
@@ -78,6 +78,7 @@ static unsigned GetEncodedCastOpcode(unsigned Opcode) {
   case Instruction::PtrToInt: return bitc::CAST_PTRTOINT;
   case Instruction::IntToPtr: return bitc::CAST_INTTOPTR;
   case Instruction::BitCast : return bitc::CAST_BITCAST;
+  case Instruction::AddrSpaceCast : return bitc::CAST_ADDRSPACECAST;
   }
 }
 
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
index 176e850..fb0e63e 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@@ -1507,6 +1507,26 @@ SDValue SelectionDAG::getMDNode(const MDNode *MD) {
   return SDValue(N, 0);
 }
 
+/// getAddrSpaceCast - Return an AddrSpaceCastSDNode.
+SDValue SelectionDAG::getAddrSpaceCast(SDLoc dl, EVT VT, SDValue Ptr,
+                                       unsigned SrcAS, unsigned DestAS) {
+  SDValue Ops[] = {Ptr};
+  FoldingSetNodeID ID;
+  AddNodeIDNode(ID, ISD::ADDRSPACECAST, getVTList(VT), &Ops[0], 1);
+  ID.AddInteger(SrcAS);
+  ID.AddInteger(DestAS);
+
+  void *IP = 0;
+  if (SDNode *E = CSEMap.FindNodeOrInsertPos(ID, IP))
+    return SDValue(E, 0);
+
+  SDNode *N = new (NodeAllocator) AddrSpaceCastSDNode(dl.getIROrder(),
+                                                      dl.getDebugLoc(),
+                                                      VT, Ptr, SrcAS, DestAS);
+  CSEMap.InsertNode(N, IP);
+  AllNodes.push_back(N);
+  return SDValue(N, 0);
+}
 
 /// getShiftAmountOperand - Return the specified value casted to
 /// the target's desired shift amount type.
@@ -5978,6 +5998,12 @@ GlobalAddressSDNode::GlobalAddressSDNode(unsigned Opc, unsigned Order,
   TheGlobal = GA;
 }
 
+AddrSpaceCastSDNode::AddrSpaceCastSDNode(unsigned Order, DebugLoc dl, EVT VT,
+                                         SDValue X, unsigned SrcAS,
+                                         unsigned DestAS)
+ : UnarySDNode(ISD::ADDRSPACECAST, Order, dl, getSDVTList(VT), X),
+   SrcAddrSpace(SrcAS), DestAddrSpace(DestAS) {}
+
 MemSDNode::MemSDNode(unsigned Opc, unsigned Order, DebugLoc dl, SDVTList VTs,
                      EVT memvt, MachineMemOperand *mmo)
  : SDNode(Opc, Order, dl, VTs), MemoryVT(memvt), MMO(mmo) {
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
index e80b630..009c590 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
@@ -2938,6 +2938,21 @@ void SelectionDAGBuilder::visitBitCast(const User &I) {
     setValue(&I, N);            // noop cast.
 }
 
+void SelectionDAGBuilder::visitAddrSpaceCast(const User &I) {
+  const TargetLowering &TLI = DAG.getTargetLoweringInfo();
+  const Value *SV = I.getOperand(0);
+  SDValue N = getValue(SV);
+  EVT DestVT = TM.getTargetLowering()->getValueType(I.getType());
+
+  unsigned SrcAS = SV->getType()->getPointerAddressSpace();
+  unsigned DestAS = I.getType()->getPointerAddressSpace();
+
+  if (!TLI.isNoopAddrSpaceCast(SrcAS, DestAS))
+    N = DAG.getAddrSpaceCast(getCurSDLoc(), DestVT, N, SrcAS, DestAS);
+
+  setValue(&I, N);
+}
+
 void SelectionDAGBuilder::visitInsertElement(const User &I) {
   const TargetLowering &TLI = DAG.getTargetLoweringInfo();
   SDValue InVec = getValue(I.getOperand(0));
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.h b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.h
index 570f927..835f643 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.h
+++ b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.h
@@ -26,6 +26,7 @@
 
 namespace llvm {
 
+class AddrSpaceCastInst;
 class AliasAnalysis;
 class AllocaInst;
 class BasicBlock;
@@ -720,6 +721,7 @@ private:
   void visitPtrToInt(const User &I);
   void visitIntToPtr(const User &I);
   void visitBitCast(const User &I);
+  void visitAddrSpaceCast(const User &I);
 
   void visitExtractElement(const User &I);
   void visitInsertElement(const User &I);
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGDumper.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGDumper.cpp
index 47bab32..c04a08d 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAGDumper.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAGDumper.cpp
@@ -224,6 +224,7 @@ std::string SDNode::getOperationName(const SelectionDAG *G) const {
   case ISD::FP_TO_SINT:                 return "fp_to_sint";
   case ISD::FP_TO_UINT:                 return "fp_to_uint";
   case ISD::BITCAST:                    return "bitcast";
+  case ISD::ADDRSPACECAST:              return "addrspacecast";
   case ISD::FP16_TO_FP32:               return "fp16_to_fp32";
   case ISD::FP32_TO_FP16:               return "fp32_to_fp16";
 
@@ -485,6 +486,13 @@ void SDNode::print_details(raw_ostream &OS, const SelectionDAG *G) const {
       OS << " " << offset;
     if (unsigned int TF = BA->getTargetFlags())
       OS << " [TF=" << TF << ']';
+  } else if (const AddrSpaceCastSDNode *ASC =
+               dyn_cast<AddrSpaceCastSDNode>(this)) {
+    OS << '['
+       << ASC->getSrcAddressSpace()
+       << " -> "
+       << ASC->getDestAddressSpace()
+       << ']';
   }
 
   if (unsigned Order = getIROrder())
diff --git a/lib/CodeGen/TargetLoweringBase.cpp b/lib/CodeGen/TargetLoweringBase.cpp
index 63743b6..30305af 100644
--- a/lib/CodeGen/TargetLoweringBase.cpp
+++ b/lib/CodeGen/TargetLoweringBase.cpp
@@ -1288,6 +1288,7 @@ int TargetLoweringBase::InstructionOpcodeToISD(unsigned Opcode) const {
   case PtrToInt:       return ISD::BITCAST;
   case IntToPtr:       return ISD::BITCAST;
   case BitCast:        return ISD::BITCAST;
+  case AddrSpaceCast:  return ISD::ADDRSPACECAST;
   case ICmp:           return ISD::SETCC;
   case FCmp:           return ISD::SETCC;
   case PHI:            return 0;
diff --git a/lib/IR/AutoUpgrade.cpp b/lib/IR/AutoUpgrade.cpp
index 52434d0..6f79919 100644
--- a/lib/IR/AutoUpgrade.cpp
+++ b/lib/IR/AutoUpgrade.cpp
@@ -447,3 +447,45 @@ void llvm::UpgradeInstWithTBAATag(Instruction *I) {
     I->setMetadata(LLVMContext::MD_tbaa, MDNode::get(I->getContext(), Elts));
   }
 }
+
+Instruction *llvm::UpgradeBitCastInst(unsigned Opc, Value *V, Type *DestTy,
+                                      Instruction *&Temp) {
+  if (Opc != Instruction::BitCast)
+    return 0;
+
+  Temp = 0;
+  Type *SrcTy = V->getType();
+  if (SrcTy->isPtrOrPtrVectorTy() && DestTy->isPtrOrPtrVectorTy() &&
+      SrcTy->getPointerAddressSpace() != DestTy->getPointerAddressSpace()) {
+    LLVMContext &Context = V->getContext();
+
+    // We have no information about target data layout, so we assume that
+    // the maximum pointer size is 64bit.
+    Type *MidTy = Type::getInt64Ty(Context);
+    Temp = CastInst::Create(Instruction::PtrToInt, V, MidTy);
+
+    return CastInst::Create(Instruction::IntToPtr, Temp, DestTy);
+  }
+
+  return 0;
+}
+
+Value *llvm::UpgradeBitCastExpr(unsigned Opc, Constant *C, Type *DestTy) {
+  if (Opc != Instruction::BitCast)
+    return 0;
+
+  Type *SrcTy = C->getType();
+  if (SrcTy->isPtrOrPtrVectorTy() && DestTy->isPtrOrPtrVectorTy() &&
+      SrcTy->getPointerAddressSpace() != DestTy->getPointerAddressSpace()) {
+    LLVMContext &Context = C->getContext();
+
+    // We have no information about target data layout, so we assume that
+    // the maximum pointer size is 64bit.
+    Type *MidTy = Type::getInt64Ty(Context);
+
+    return ConstantExpr::getIntToPtr(ConstantExpr::getPtrToInt(C, MidTy),
+                                     DestTy);
+  }
+
+  return 0;
+}
diff --git a/lib/IR/ConstantFold.cpp b/lib/IR/ConstantFold.cpp
index 3319ec5..f5e225c 100644
--- a/lib/IR/ConstantFold.cpp
+++ b/lib/IR/ConstantFold.cpp
@@ -689,6 +689,8 @@ Constant *llvm::ConstantFoldCastInstruction(unsigned opc, Constant *V,
   }
   case Instruction::BitCast:
     return FoldBitCast(V, DestTy);
+  case Instruction::AddrSpaceCast:
+    return 0;
   }
 }
 
diff --git a/lib/IR/Constants.cpp b/lib/IR/Constants.cpp
index 9067b34..a8a325a 100644
--- a/lib/IR/Constants.cpp
+++ b/lib/IR/Constants.cpp
@@ -1126,6 +1126,7 @@ getWithOperands(ArrayRef<Constant*> Ops, Type *Ty) const {
   case Instruction::PtrToInt:
   case Instruction::IntToPtr:
   case Instruction::BitCast:
+  case Instruction::AddrSpaceCast:
     return ConstantExpr::getCast(getOpcode(), Ops[0], Ty);
   case Instruction::Select:
     return ConstantExpr::getSelect(Ops[0], Ops[1], Ops[2]);
@@ -1461,6 +1462,7 @@ Constant *ConstantExpr::getCast(unsigned oc, Constant *C, Type *Ty) {
   case Instruction::PtrToInt: return getPtrToInt(C, Ty);
   case Instruction::IntToPtr: return getIntToPtr(C, Ty);
   case Instruction::BitCast:  return getBitCast(C, Ty);
+  case Instruction::AddrSpaceCast:  return getAddrSpaceCast(C, Ty);
   }
 }
 
@@ -1489,6 +1491,11 @@ Constant *ConstantExpr::getPointerCast(Constant *S, Type *Ty) {
 
   if (Ty->isIntOrIntVectorTy())
     return getPtrToInt(S, Ty);
+
+  unsigned SrcAS = S->getType()->getPointerAddressSpace();
+  if (Ty->isPtrOrPtrVectorTy() && SrcAS != Ty->getPointerAddressSpace())
+    return getAddrSpaceCast(S, Ty);
+
   return getBitCast(S, Ty);
 }
 
@@ -1662,6 +1669,13 @@ Constant *ConstantExpr::getBitCast(Constant *C, Type *DstTy) {
   return getFoldedCast(Instruction::BitCast, C, DstTy);
 }
 
+Constant *ConstantExpr::getAddrSpaceCast(Constant *C, Type *DstTy) {
+  assert(CastInst::castIsValid(Instruction::AddrSpaceCast, C, DstTy) &&
+         "Invalid constantexpr addrspacecast!");
+
+  return getFoldedCast(Instruction::AddrSpaceCast, C, DstTy);
+}
+
 Constant *ConstantExpr::get(unsigned Opcode, Constant *C1, Constant *C2,
                             unsigned Flags) {
   // Check the operands for consistency first.
diff --git a/lib/IR/Core.cpp b/lib/IR/Core.cpp
index 63cc2f6..c70f459 100644
--- a/lib/IR/Core.cpp
+++ b/lib/IR/Core.cpp
@@ -1033,6 +1033,12 @@ LLVMValueRef LLVMConstBitCast(LLVMValueRef ConstantVal, LLVMTypeRef ToType) {
                                        unwrap(ToType)));
 }
 
+LLVMValueRef LLVMConstAddrSpaceCast(LLVMValueRef ConstantVal,
+                                    LLVMTypeRef ToType) {
+  return wrap(ConstantExpr::getAddrSpaceCast(unwrap<Constant>(ConstantVal),
+                                             unwrap(ToType)));
+}
+
 LLVMValueRef LLVMConstZExtOrBitCast(LLVMValueRef ConstantVal,
                                     LLVMTypeRef ToType) {
   return wrap(ConstantExpr::getZExtOrBitCast(unwrap<Constant>(ConstantVal),
@@ -2318,6 +2324,11 @@ LLVMValueRef LLVMBuildBitCast(LLVMBuilderRef B, LLVMValueRef Val,
   return wrap(unwrap(B)->CreateBitCast(unwrap(Val), unwrap(DestTy), Name));
 }
 
+LLVMValueRef LLVMBuildAddrSpaceCast(LLVMBuilderRef B, LLVMValueRef Val,
+                                    LLVMTypeRef DestTy, const char *Name) {
+  return wrap(unwrap(B)->CreateAddrSpaceCast(unwrap(Val), unwrap(DestTy), Name));
+}
+
 LLVMValueRef LLVMBuildZExtOrBitCast(LLVMBuilderRef B, LLVMValueRef Val,
                                     LLVMTypeRef DestTy, const char *Name) {
   return wrap(unwrap(B)->CreateZExtOrBitCast(unwrap(Val), unwrap(DestTy),
diff --git a/lib/IR/Instruction.cpp b/lib/IR/Instruction.cpp
index 2b5a0b3..a7773c4 100644
--- a/lib/IR/Instruction.cpp
+++ b/lib/IR/Instruction.cpp
@@ -223,18 +223,19 @@ const char *Instruction::getOpcodeName(unsigned OpCode) {
   case GetElementPtr: return "getelementptr";
 
   // Convert instructions...
-  case Trunc:     return "trunc";
-  case ZExt:      return "zext";
-  case SExt:      return "sext";
-  case FPTrunc:   return "fptrunc";
-  case FPExt:     return "fpext";
-  case FPToUI:    return "fptoui";
-  case FPToSI:    return "fptosi";
-  case UIToFP:    return "uitofp";
-  case SIToFP:    return "sitofp";
-  case IntToPtr:  return "inttoptr";
-  case PtrToInt:  return "ptrtoint";
-  case BitCast:   return "bitcast";
+  case Trunc:         return "trunc";
+  case ZExt:          return "zext";
+  case SExt:          return "sext";
+  case FPTrunc:       return "fptrunc";
+  case FPExt:         return "fpext";
+  case FPToUI:        return "fptoui";
+  case FPToSI:        return "fptosi";
+  case UIToFP:        return "uitofp";
+  case SIToFP:        return "sitofp";
+  case IntToPtr:      return "inttoptr";
+  case PtrToInt:      return "ptrtoint";
+  case BitCast:       return "bitcast";
+  case AddrSpaceCast: return "addrspacecast";
 
   // Other instructions...
   case ICmp:           return "icmp";
diff --git a/lib/IR/Instructions.cpp b/lib/IR/Instructions.cpp
index 37b6782..8a6b77b 100644
--- a/lib/IR/Instructions.cpp
+++ b/lib/IR/Instructions.cpp
@@ -2095,7 +2095,9 @@ bool CastInst::isNoopCast(Instruction::CastOps Opcode,
     case Instruction::SIToFP:
     case Instruction::FPToUI:
     case Instruction::FPToSI:
-      return false; // These always modify bits
+    case Instruction::AddrSpaceCast:
+      // TODO: Target informations may give a more accurate answer here.
+      return false;
     case Instruction::BitCast:
       return true;  // BitCast never modifies bits.
     case Instruction::PtrToInt:
@@ -2137,44 +2139,46 @@ unsigned CastInst::isEliminableCastPair(
   // ZEXT          <       Integral   Unsigned     Integer      Any
   // SEXT          <       Integral    Signed      Integer      Any
   // FPTOUI       n/a      FloatPt      n/a        Integral   Unsigned
-  // FPTOSI       n/a      FloatPt      n/a        Integral    Signed 
-  // UITOFP       n/a      Integral   Unsigned     FloatPt      n/a   
-  // SITOFP       n/a      Integral    Signed      FloatPt      n/a   
-  // FPTRUNC       >       FloatPt      n/a        FloatPt      n/a   
-  // FPEXT         <       FloatPt      n/a        FloatPt      n/a   
+  // FPTOSI       n/a      FloatPt      n/a        Integral    Signed
+  // UITOFP       n/a      Integral   Unsigned     FloatPt      n/a
+  // SITOFP       n/a      Integral    Signed      FloatPt      n/a
+  // FPTRUNC       >       FloatPt      n/a        FloatPt      n/a
+  // FPEXT         <       FloatPt      n/a        FloatPt      n/a
   // PTRTOINT     n/a      Pointer      n/a        Integral   Unsigned
   // INTTOPTR     n/a      Integral   Unsigned     Pointer      n/a
-  // BITCAST       =       FirstClass   n/a       FirstClass    n/a   
+  // BITCAST       =       FirstClass   n/a       FirstClass    n/a
+  // ADDRSPCST    n/a      Pointer      n/a        Pointer      n/a
   //
   // NOTE: some transforms are safe, but we consider them to be non-profitable.
   // For example, we could merge "fptoui double to i32" + "zext i32 to i64",
   // into "fptoui double to i64", but this loses information about the range
-  // of the produced value (we no longer know the top-part is all zeros). 
+  // of the produced value (we no longer know the top-part is all zeros).
   // Further this conversion is often much more expensive for typical hardware,
-  // and causes issues when building libgcc.  We disallow fptosi+sext for the 
+  // and causes issues when building libgcc.  We disallow fptosi+sext for the
   // same reason.
-  const unsigned numCastOps = 
+  const unsigned numCastOps =
     Instruction::CastOpsEnd - Instruction::CastOpsBegin;
   static const uint8_t CastResults[numCastOps][numCastOps] = {
-    // T        F  F  U  S  F  F  P  I  B   -+
-    // R  Z  S  P  P  I  I  T  P  2  N  T    |
-    // U  E  E  2  2  2  2  R  E  I  T  C    +- secondOp
-    // N  X  X  U  S  F  F  N  X  N  2  V    |
-    // C  T  T  I  I  P  P  C  T  T  P  T   -+
-    {  1, 0, 0,99,99, 0, 0,99,99,99, 0, 3 }, // Trunc      -+
-    {  8, 1, 9,99,99, 2, 0,99,99,99, 2, 3 }, // ZExt        |
-    {  8, 0, 1,99,99, 0, 2,99,99,99, 0, 3 }, // SExt        |
-    {  0, 0, 0,99,99, 0, 0,99,99,99, 0, 3 }, // FPToUI      |
-    {  0, 0, 0,99,99, 0, 0,99,99,99, 0, 3 }, // FPToSI      |
-    { 99,99,99, 0, 0,99,99, 0, 0,99,99, 4 }, // UIToFP      +- firstOp
-    { 99,99,99, 0, 0,99,99, 0, 0,99,99, 4 }, // SIToFP      |
-    { 99,99,99, 0, 0,99,99, 1, 0,99,99, 4 }, // FPTrunc     |
-    { 99,99,99, 2, 2,99,99,10, 2,99,99, 4 }, // FPExt       |
-    {  1, 0, 0,99,99, 0, 0,99,99,99, 7, 3 }, // PtrToInt    |
-    { 99,99,99,99,99,99,99,99,99,13,99,12 }, // IntToPtr    |
-    {  5, 5, 5, 6, 6, 5, 5, 6, 6,11, 5, 1 }, // BitCast    -+
+    // T        F  F  U  S  F  F  P  I  B  A  -+
+    // R  Z  S  P  P  I  I  T  P  2  N  T  S   |
+    // U  E  E  2  2  2  2  R  E  I  T  C  C   +- secondOp
+    // N  X  X  U  S  F  F  N  X  N  2  V  V   |
+    // C  T  T  I  I  P  P  C  T  T  P  T  T  -+
+    {  1, 0, 0,99,99, 0, 0,99,99,99, 0, 3, 0}, // Trunc         -+
+    {  8, 1, 9,99,99, 2, 0,99,99,99, 2, 3, 0}, // ZExt           |
+    {  8, 0, 1,99,99, 0, 2,99,99,99, 0, 3, 0}, // SExt           |
+    {  0, 0, 0,99,99, 0, 0,99,99,99, 0, 3, 0}, // FPToUI         |
+    {  0, 0, 0,99,99, 0, 0,99,99,99, 0, 3, 0}, // FPToSI         |
+    { 99,99,99, 0, 0,99,99, 0, 0,99,99, 4, 0}, // UIToFP         +- firstOp
+    { 99,99,99, 0, 0,99,99, 0, 0,99,99, 4, 0}, // SIToFP         |
+    { 99,99,99, 0, 0,99,99, 1, 0,99,99, 4, 0}, // FPTrunc        |
+    { 99,99,99, 2, 2,99,99,10, 2,99,99, 4, 0}, // FPExt          |
+    {  1, 0, 0,99,99, 0, 0,99,99,99, 7, 3, 0}, // PtrToInt       |
+    { 99,99,99,99,99,99,99,99,99,11,99,15, 0}, // IntToPtr       |
+    {  5, 5, 5, 6, 6, 5, 5, 6, 6,16, 5, 1,14}, // BitCast        |
+    {  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,13,12}, // AddrSpaceCast -+
   };
-  
+
   // If either of the casts are a bitcast from scalar to vector, disallow the
   // merging. However, bitcast of A->B->A are allowed.
   bool isFirstBitcast  = (firstOp == Instruction::BitCast);
@@ -2191,47 +2195,50 @@ unsigned CastInst::isEliminableCastPair(
                             [secondOp-Instruction::CastOpsBegin];
   switch (ElimCase) {
     case 0: 
-      // categorically disallowed
+      // Categorically disallowed.
       return 0;
     case 1: 
-      // allowed, use first cast's opcode
+      // Allowed, use first cast's opcode.
       return firstOp;
     case 2: 
-      // allowed, use second cast's opcode
+      // Allowed, use second cast's opcode.
       return secondOp;
     case 3: 
-      // no-op cast in second op implies firstOp as long as the DestTy 
+      // No-op cast in second op implies firstOp as long as the DestTy
       // is integer and we are not converting between a vector and a
       // non vector type.
       if (!SrcTy->isVectorTy() && DstTy->isIntegerTy())
         return firstOp;
       return 0;
     case 4:
-      // no-op cast in second op implies firstOp as long as the DestTy
+      // No-op cast in second op implies firstOp as long as the DestTy
       // is floating point.
       if (DstTy->isFloatingPointTy())
         return firstOp;
       return 0;
     case 5: 
-      // no-op cast in first op implies secondOp as long as the SrcTy
+      // No-op cast in first op implies secondOp as long as the SrcTy
       // is an integer.
       if (SrcTy->isIntegerTy())
         return secondOp;
       return 0;
     case 6:
-      // no-op cast in first op implies secondOp as long as the SrcTy
+      // No-op cast in first op implies secondOp as long as the SrcTy
       // is a floating point.
       if (SrcTy->isFloatingPointTy())
         return secondOp;
       return 0;
     case 7: {
+      // Cannot simplify if address spaces are different!
+      if (SrcTy->getPointerAddressSpace() != DstTy->getPointerAddressSpace())
+        return 0;
+
       unsigned MidSize = MidTy->getScalarSizeInBits();
-      // Check the address spaces first. If we know they are in the same address
-      // space, the pointer sizes must be the same so we can still fold this
-      // without knowing the actual sizes as long we know that the intermediate
-      // pointer is the largest possible pointer size.
-      if (MidSize == 64 &&
-          SrcTy->getPointerAddressSpace() == DstTy->getPointerAddressSpace())
+      // We can still fold this without knowing the actual sizes as long we
+      // know that the intermediate pointer is the largest possible
+      // pointer size.
+      // FIXME: Is this always true?
+      if (MidSize == 64)
         return Instruction::BitCast;
 
       // ptrtoint, inttoptr -> bitcast (ptr -> ptr) if int size is >= ptr size.
@@ -2254,7 +2261,8 @@ unsigned CastInst::isEliminableCastPair(
         return firstOp;
       return secondOp;
     }
-    case 9: // zext, sext -> zext, because sext can't sign extend after zext
+    case 9:
+      // zext, sext -> zext, because sext can't sign extend after zext
       return Instruction::ZExt;
     case 10:
       // fpext followed by ftrunc is allowed if the bit size returned to is
@@ -2263,46 +2271,6 @@ unsigned CastInst::isEliminableCastPair(
         return Instruction::BitCast;
       return 0; // If the types are not the same we can't eliminate it.
     case 11: {
-      // bitcast followed by ptrtoint is allowed as long as the bitcast is a
-      // pointer to pointer cast, and the pointers are the same size.
-      PointerType *SrcPtrTy = dyn_cast<PointerType>(SrcTy);
-      PointerType *MidPtrTy = dyn_cast<PointerType>(MidTy);
-      if (!SrcPtrTy || !MidPtrTy)
-        return 0;
-
-      // If the address spaces are the same, we know they are the same size
-      // without size information
-      if (SrcPtrTy->getAddressSpace() == MidPtrTy->getAddressSpace())
-        return secondOp;
-
-      if (!SrcIntPtrTy || !MidIntPtrTy)
-        return 0;
-
-      if (SrcIntPtrTy->getScalarSizeInBits() ==
-          MidIntPtrTy->getScalarSizeInBits())
-        return secondOp;
-
-      return 0;
-    }
-    case 12: {
-      // inttoptr, bitcast -> inttoptr if bitcast is a ptr to ptr cast
-      // and the ptrs are to address spaces of the same size
-      PointerType *MidPtrTy = dyn_cast<PointerType>(MidTy);
-      PointerType *DstPtrTy = dyn_cast<PointerType>(DstTy);
-      if (!MidPtrTy || !DstPtrTy)
-        return 0;
-
-      if (MidPtrTy->getAddressSpace() == DstPtrTy->getAddressSpace())
-        return firstOp;
-
-      if (MidIntPtrTy &&
-          DstIntPtrTy &&
-          MidIntPtrTy->getScalarSizeInBits() ==
-          DstIntPtrTy->getScalarSizeInBits())
-        return firstOp;
-      return 0;
-    }
-    case 13: {
       // inttoptr, ptrtoint -> bitcast if SrcSize<=PtrSize and SrcSize==DstSize
       if (!MidIntPtrTy)
         return 0;
@@ -2313,8 +2281,65 @@ unsigned CastInst::isEliminableCastPair(
         return Instruction::BitCast;
       return 0;
     }
+    case 12: {
+      // addrspacecast, addrspacecast -> bitcast,       if SrcAS == DstAS
+      // addrspacecast, addrspacecast -> addrspacecast, if SrcAS != DstAS
+      if (SrcTy->getPointerAddressSpace() != DstTy->getPointerAddressSpace())
+        return Instruction::AddrSpaceCast;
+      return Instruction::BitCast;
+    }
+    case 13:
+      // FIXME: this state can be merged with (1), but the following assert
+      // is useful to check the correcteness of the sequence due to semantic
+      // change of bitcast.
+      assert(
+        SrcTy->isPtrOrPtrVectorTy() &&
+        MidTy->isPtrOrPtrVectorTy() &&
+        DstTy->isPtrOrPtrVectorTy() &&
+        SrcTy->getPointerAddressSpace() != MidTy->getPointerAddressSpace() &&
+        MidTy->getPointerAddressSpace() == DstTy->getPointerAddressSpace() &&
+        "Illegal addrspacecast, bitcast sequence!");
+      // Allowed, use first cast's opcode
+      return firstOp;
+    case 14:
+      // FIXME: this state can be merged with (2), but the following assert
+      // is useful to check the correcteness of the sequence due to semantic
+      // change of bitcast.
+      assert(
+        SrcTy->isPtrOrPtrVectorTy() &&
+        MidTy->isPtrOrPtrVectorTy() &&
+        DstTy->isPtrOrPtrVectorTy() &&
+        SrcTy->getPointerAddressSpace() == MidTy->getPointerAddressSpace() &&
+        MidTy->getPointerAddressSpace() != DstTy->getPointerAddressSpace() &&
+        "Illegal bitcast, addrspacecast sequence!");
+      // Allowed, use second cast's opcode
+      return secondOp;
+    case 15:
+      // FIXME: this state can be merged with (1), but the following assert
+      // is useful to check the correcteness of the sequence due to semantic
+      // change of bitcast.
+      assert(
+        SrcTy->isIntOrIntVectorTy() &&
+        MidTy->isPtrOrPtrVectorTy() &&
+        DstTy->isPtrOrPtrVectorTy() &&
+        MidTy->getPointerAddressSpace() == DstTy->getPointerAddressSpace() &&
+        "Illegal inttoptr, bitcast sequence!");
+      // Allowed, use first cast's opcode
+      return firstOp;
+    case 16:
+      // FIXME: this state can be merged with (2), but the following assert
+      // is useful to check the correcteness of the sequence due to semantic
+      // change of bitcast.
+      assert(
+        SrcTy->isPtrOrPtrVectorTy() &&
+        MidTy->isPtrOrPtrVectorTy() &&
+        DstTy->isIntOrIntVectorTy() &&
+        SrcTy->getPointerAddressSpace() == MidTy->getPointerAddressSpace() &&
+        "Illegal bitcast, ptrtoint sequence!");
+      // Allowed, use second cast's opcode
+      return secondOp;
     case 99: 
-      // cast combination can't happen (error in input). This is for all cases
+      // Cast combination can't happen (error in input). This is for all cases
       // where the MidTy is not the same for the two cast instructions.
       llvm_unreachable("Invalid Cast Combination");
     default:
@@ -2327,19 +2352,20 @@ CastInst *CastInst::Create(Instruction::CastOps op, Value *S, Type *Ty,
   assert(castIsValid(op, S, Ty) && "Invalid cast!");
   // Construct and return the appropriate CastInst subclass
   switch (op) {
-    case Trunc:    return new TruncInst    (S, Ty, Name, InsertBefore);
-    case ZExt:     return new ZExtInst     (S, Ty, Name, InsertBefore);
-    case SExt:     return new SExtInst     (S, Ty, Name, InsertBefore);
-    case FPTrunc:  return new FPTruncInst  (S, Ty, Name, InsertBefore);
-    case FPExt:    return new FPExtInst    (S, Ty, Name, InsertBefore);
-    case UIToFP:   return new UIToFPInst   (S, Ty, Name, InsertBefore);
-    case SIToFP:   return new SIToFPInst   (S, Ty, Name, InsertBefore);
-    case FPToUI:   return new FPToUIInst   (S, Ty, Name, InsertBefore);
-    case FPToSI:   return new FPToSIInst   (S, Ty, Name, InsertBefore);
-    case PtrToInt: return new PtrToIntInst (S, Ty, Name, InsertBefore);
-    case IntToPtr: return new IntToPtrInst (S, Ty, Name, InsertBefore);
-    case BitCast:  return new BitCastInst  (S, Ty, Name, InsertBefore);
-    default: llvm_unreachable("Invalid opcode provided");
+  case Trunc:         return new TruncInst         (S, Ty, Name, InsertBefore);
+  case ZExt:          return new ZExtInst          (S, Ty, Name, InsertBefore);
+  case SExt:          return new SExtInst          (S, Ty, Name, InsertBefore);
+  case FPTrunc:       return new FPTruncInst       (S, Ty, Name, InsertBefore);
+  case FPExt:         return new FPExtInst         (S, Ty, Name, InsertBefore);
+  case UIToFP:        return new UIToFPInst        (S, Ty, Name, InsertBefore);
+  case SIToFP:        return new SIToFPInst        (S, Ty, Name, InsertBefore);
+  case FPToUI:        return new FPToUIInst        (S, Ty, Name, InsertBefore);
+  case FPToSI:        return new FPToSIInst        (S, Ty, Name, InsertBefore);
+  case PtrToInt:      return new PtrToIntInst      (S, Ty, Name, InsertBefore);
+  case IntToPtr:      return new IntToPtrInst      (S, Ty, Name, InsertBefore);
+  case BitCast:       return new BitCastInst       (S, Ty, Name, InsertBefore);
+  case AddrSpaceCast: return new AddrSpaceCastInst (S, Ty, Name, InsertBefore);
+  default: llvm_unreachable("Invalid opcode provided");
   }
 }
 
@@ -2348,19 +2374,20 @@ CastInst *CastInst::Create(Instruction::CastOps op, Value *S, Type *Ty,
   assert(castIsValid(op, S, Ty) && "Invalid cast!");
   // Construct and return the appropriate CastInst subclass
   switch (op) {
-    case Trunc:    return new TruncInst    (S, Ty, Name, InsertAtEnd);
-    case ZExt:     return new ZExtInst     (S, Ty, Name, InsertAtEnd);
-    case SExt:     return new SExtInst     (S, Ty, Name, InsertAtEnd);
-    case FPTrunc:  return new FPTruncInst  (S, Ty, Name, InsertAtEnd);
-    case FPExt:    return new FPExtInst    (S, Ty, Name, InsertAtEnd);
-    case UIToFP:   return new UIToFPInst   (S, Ty, Name, InsertAtEnd);
-    case SIToFP:   return new SIToFPInst   (S, Ty, Name, InsertAtEnd);
-    case FPToUI:   return new FPToUIInst   (S, Ty, Name, InsertAtEnd);
-    case FPToSI:   return new FPToSIInst   (S, Ty, Name, InsertAtEnd);
-    case PtrToInt: return new PtrToIntInst (S, Ty, Name, InsertAtEnd);
-    case IntToPtr: return new IntToPtrInst (S, Ty, Name, InsertAtEnd);
-    case BitCast:  return new BitCastInst  (S, Ty, Name, InsertAtEnd);
-    default: llvm_unreachable("Invalid opcode provided");
+  case Trunc:         return new TruncInst         (S, Ty, Name, InsertAtEnd);
+  case ZExt:          return new ZExtInst          (S, Ty, Name, InsertAtEnd);
+  case SExt:          return new SExtInst          (S, Ty, Name, InsertAtEnd);
+  case FPTrunc:       return new FPTruncInst       (S, Ty, Name, InsertAtEnd);
+  case FPExt:         return new FPExtInst         (S, Ty, Name, InsertAtEnd);
+  case UIToFP:        return new UIToFPInst        (S, Ty, Name, InsertAtEnd);
+  case SIToFP:        return new SIToFPInst        (S, Ty, Name, InsertAtEnd);
+  case FPToUI:        return new FPToUIInst        (S, Ty, Name, InsertAtEnd);
+  case FPToSI:        return new FPToSIInst        (S, Ty, Name, InsertAtEnd);
+  case PtrToInt:      return new PtrToIntInst      (S, Ty, Name, InsertAtEnd);
+  case IntToPtr:      return new IntToPtrInst      (S, Ty, Name, InsertAtEnd);
+  case BitCast:       return new BitCastInst       (S, Ty, Name, InsertAtEnd);
+  case AddrSpaceCast: return new AddrSpaceCastInst (S, Ty, Name, InsertAtEnd);
+  default: llvm_unreachable("Invalid opcode provided");
   }
 }
 
@@ -2425,6 +2452,11 @@ CastInst *CastInst::CreatePointerCast(Value *S, Type *Ty,
 
   if (Ty->isIntOrIntVectorTy())
     return Create(Instruction::PtrToInt, S, Ty, Name, InsertAtEnd);
+
+  Type *STy = S->getType();
+  if (STy->getPointerAddressSpace() != Ty->getPointerAddressSpace())
+    return Create(Instruction::AddrSpaceCast, S, Ty, Name, InsertAtEnd);
+
   return Create(Instruction::BitCast, S, Ty, Name, InsertAtEnd);
 }
 
@@ -2442,6 +2474,11 @@ CastInst *CastInst::CreatePointerCast(Value *S, Type *Ty,
 
   if (Ty->isIntOrIntVectorTy())
     return Create(Instruction::PtrToInt, S, Ty, Name, InsertBefore);
+
+  Type *STy = S->getType();
+  if (STy->getPointerAddressSpace() != Ty->getPointerAddressSpace())
+    return Create(Instruction::AddrSpaceCast, S, Ty, Name, InsertBefore);
+
   return Create(Instruction::BitCast, S, Ty, Name, InsertBefore);
 }
 
@@ -2687,7 +2724,8 @@ CastInst::getCastOpcode(
     return BitCast;
   } else if (DestTy->isPointerTy()) {
     if (SrcTy->isPointerTy()) {
-      // TODO: Address space pointer sizes may not match
+      if (DestTy->getPointerAddressSpace() != SrcTy->getPointerAddressSpace())
+        return AddrSpaceCast;
       return BitCast;                               // ptr -> ptr
     } else if (SrcTy->isIntegerTy()) {
       return IntToPtr;                              // int -> ptr
@@ -2782,13 +2820,27 @@ CastInst::castIsValid(Instruction::CastOps op, Value *S, Type *DstTy) {
   case Instruction::BitCast:
     // BitCast implies a no-op cast of type only. No bits change.
     // However, you can't cast pointers to anything but pointers.
-    if (SrcTy->isPointerTy() != DstTy->isPointerTy())
+    if (SrcTy->isPtrOrPtrVectorTy() != DstTy->isPtrOrPtrVectorTy())
       return false;
 
-    // Now we know we're not dealing with a pointer/non-pointer mismatch. In all
-    // these cases, the cast is okay if the source and destination bit widths
-    // are identical.
-    return SrcTy->getPrimitiveSizeInBits() == DstTy->getPrimitiveSizeInBits();
+    // For non pointer cases, the cast is okay if the source and destination bit
+    // widths are identical.
+    if (!SrcTy->isPtrOrPtrVectorTy())
+      return SrcTy->getPrimitiveSizeInBits() == DstTy->getPrimitiveSizeInBits();
+
+    // If both are pointers then the address spaces must match and vector of
+    // pointers must have the same number of elements.
+    return SrcTy->getPointerAddressSpace() == DstTy->getPointerAddressSpace() &&
+           SrcTy->isVectorTy() == DstTy->isVectorTy() &&
+           (!SrcTy->isVectorTy() ||
+            SrcTy->getVectorNumElements() == SrcTy->getVectorNumElements());
+
+  case Instruction::AddrSpaceCast:
+    return SrcTy->isPtrOrPtrVectorTy() && DstTy->isPtrOrPtrVectorTy() &&
+           SrcTy->getPointerAddressSpace() != DstTy->getPointerAddressSpace() &&
+           SrcTy->isVectorTy() == DstTy->isVectorTy() &&
+           (!SrcTy->isVectorTy() ||
+            SrcTy->getVectorNumElements() == SrcTy->getVectorNumElements());
   }
 }
 
@@ -2935,6 +2987,18 @@ BitCastInst::BitCastInst(
   assert(castIsValid(getOpcode(), S, Ty) && "Illegal BitCast");
 }
 
+AddrSpaceCastInst::AddrSpaceCastInst(
+  Value *S, Type *Ty, const Twine &Name, Instruction *InsertBefore
+) : CastInst(Ty, AddrSpaceCast, S, Name, InsertBefore) {
+  assert(castIsValid(getOpcode(), S, Ty) && "Illegal AddrSpaceCast");
+}
+
+AddrSpaceCastInst::AddrSpaceCastInst(
+  Value *S, Type *Ty, const Twine &Name, BasicBlock *InsertAtEnd
+) : CastInst(Ty, AddrSpaceCast, S, Name, InsertAtEnd) {
+  assert(castIsValid(getOpcode(), S, Ty) && "Illegal AddrSpaceCast");
+}
+
 //===----------------------------------------------------------------------===//
 //                               CmpInst Classes
 //===----------------------------------------------------------------------===//
@@ -3553,6 +3617,10 @@ BitCastInst *BitCastInst::clone_impl() const {
   return new BitCastInst(getOperand(0), getType());
 }
 
+AddrSpaceCastInst *AddrSpaceCastInst::clone_impl() const {
+  return new AddrSpaceCastInst(getOperand(0), getType());
+}
+
 CallInst *CallInst::clone_impl() const {
   return  new(getNumOperands()) CallInst(*this);
 }
diff --git a/lib/IR/Value.cpp b/lib/IR/Value.cpp
index 6698f83..35808a6 100644
--- a/lib/IR/Value.cpp
+++ b/lib/IR/Value.cpp
@@ -365,7 +365,8 @@ static Value *stripPointerCastsAndOffsets(Value *V) {
         break;
       }
       V = GEP->getPointerOperand();
-    } else if (Operator::getOpcode(V) == Instruction::BitCast) {
+    } else if (Operator::getOpcode(V) == Instruction::BitCast ||
+               Operator::getOpcode(V) == Instruction::AddrSpaceCast) {
       V = cast<Operator>(V)->getOperand(0);
     } else if (GlobalAlias *GA = dyn_cast<GlobalAlias>(V)) {
       if (StripKind == PSK_ZeroIndices || GA->mayBeOverridden())
diff --git a/lib/IR/Verifier.cpp b/lib/IR/Verifier.cpp
index 1bb3e34..27bc13b 100644
--- a/lib/IR/Verifier.cpp
+++ b/lib/IR/Verifier.cpp
@@ -283,6 +283,7 @@ namespace {
     void visitIntToPtrInst(IntToPtrInst &I);
     void visitPtrToIntInst(PtrToIntInst &I);
     void visitBitCastInst(BitCastInst &I);
+    void visitAddrSpaceCastInst(AddrSpaceCastInst &I);
     void visitPHINode(PHINode &PN);
     void visitBinaryOperator(BinaryOperator &B);
     void visitICmpInst(ICmpInst &IC);
@@ -965,11 +966,9 @@ void Verifier::VerifyBitcastType(const Value *V, Type *DestTy, Type *SrcTy) {
   unsigned SrcAS = SrcTy->getPointerAddressSpace();
   unsigned DstAS = DestTy->getPointerAddressSpace();
 
-  unsigned SrcASSize = DL->getPointerSizeInBits(SrcAS);
-  unsigned DstASSize = DL->getPointerSizeInBits(DstAS);
-  Assert1(SrcASSize == DstASSize,
-          "Bitcasts between pointers of different address spaces must have "
-          "the same size pointers, otherwise use PtrToInt/IntToPtr.", V);
+  Assert1(SrcAS == DstAS,
+          "Bitcasts between pointers of different address spaces is not legal."
+          "Use AddrSpaceCast instead.", V);
 }
 
 void Verifier::VerifyConstantExprBitcastType(const ConstantExpr *CE) {
@@ -1455,6 +1454,22 @@ void Verifier::visitBitCastInst(BitCastInst &I) {
   visitInstruction(I);
 }
 
+void Verifier::visitAddrSpaceCastInst(AddrSpaceCastInst &I) {
+  Type *SrcTy = I.getOperand(0)->getType();
+  Type *DestTy = I.getType();
+
+  Assert1(SrcTy->isPtrOrPtrVectorTy(),
+          "AddrSpaceCast source must be a pointer", &I);
+  Assert1(DestTy->isPtrOrPtrVectorTy(),
+          "AddrSpaceCast result must be a pointer", &I);
+  Assert1(SrcTy->getPointerAddressSpace() != DestTy->getPointerAddressSpace(),
+          "AddrSpaceCast must be between different address spaces", &I);
+  if (SrcTy->isVectorTy())
+    Assert1(SrcTy->getVectorNumElements() == DestTy->getVectorNumElements(),
+            "AddrSpaceCast vector pointer number of elements mismatch", &I);
+  visitInstruction(I);
+}
+
 /// visitPHINode - Ensure that a PHI node is well formed.
 ///
 void Verifier::visitPHINode(PHINode &PN) {
diff --git a/lib/Target/NVPTX/NVPTXGenericToNVVM.cpp b/lib/Target/NVPTX/NVPTXGenericToNVVM.cpp
index 9f92a5b..9fb0dd8 100644
--- a/lib/Target/NVPTX/NVPTXGenericToNVVM.cpp
+++ b/lib/Target/NVPTX/NVPTXGenericToNVVM.cpp
@@ -142,7 +142,7 @@ bool GenericToNVVM::runOnModule(Module &M) {
     GlobalVariable *GV = I->first;
     GlobalVariable *NewGV = I->second;
     ++I;
-    Constant *BitCastNewGV = ConstantExpr::getBitCast(NewGV, GV->getType());
+    Constant *BitCastNewGV = ConstantExpr::getPointerCast(NewGV, GV->getType());
     // At this point, the remaining uses of GV should be found only in global
     // variable initializers, as other uses have been already been removed
     // while walking through the instructions in function definitions.
diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index a878ea8..aa96420 100644
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -92,7 +92,7 @@ static SDValue ExtractSubVector(SDValue Vec, unsigned IdxVal,
                                VecIdx);
 
   return Result;
-  
+
 }
 /// Generate a DAG to grab 128-bits from a vector > 128 bits.  This
 /// sets things up to match to an AVX VEXTRACTF128 / VEXTRACTI128
@@ -1765,6 +1765,13 @@ bool X86TargetLowering::getStackCookieLocation(unsigned &AddressSpace,
   return true;
 }
 
+bool X86TargetLowering::isNoopAddrSpaceCast(unsigned SrcAS,
+                                            unsigned DestAS) const {
+  assert(SrcAS != DestAS && "Expected different address spaces!");
+
+  return SrcAS < 256 && DestAS < 256;
+}
+
 //===----------------------------------------------------------------------===//
 //               Return Value Calling Convention Implementation
 //===----------------------------------------------------------------------===//
diff --git a/lib/Target/X86/X86ISelLowering.h b/lib/Target/X86/X86ISelLowering.h
index 07a36f9..bc3dd60 100644
--- a/lib/Target/X86/X86ISelLowering.h
+++ b/lib/Target/X86/X86ISelLowering.h
@@ -775,6 +775,8 @@ namespace llvm {
     SDValue BuildFILD(SDValue Op, EVT SrcVT, SDValue Chain, SDValue StackSlot,
                       SelectionDAG &DAG) const;
 
+    virtual bool isNoopAddrSpaceCast(unsigned SrcAS, unsigned DestAS) const LLVM_OVERRIDE;
+
     /// \brief Reset the operation actions based on target options.
     virtual void resetOperationActions();
 
diff --git a/test/Assembler/ConstantExprFoldCast.ll b/test/Assembler/ConstantExprFoldCast.ll
index 0ce6e84..161a4ca 100644
--- a/test/Assembler/ConstantExprFoldCast.ll
+++ b/test/Assembler/ConstantExprFoldCast.ll
@@ -12,3 +12,5 @@
 @F = global i32* inttoptr (i32 add (i32 5, i32 -5) to i32*)
 @G = global i32* inttoptr (i32 sub (i32 5, i32 5) to i32*)
 
+; Address space cast AS0 null-> AS1 null
+@H = global i32 addrspace(1)* addrspacecast(i32* null to i32 addrspace(1)*)
diff --git a/test/Assembler/ConstantExprNoFold.ll b/test/Assembler/ConstantExprNoFold.ll
index 83e8909..b41959f 100644
--- a/test/Assembler/ConstantExprNoFold.ll
+++ b/test/Assembler/ConstantExprNoFold.ll
@@ -21,3 +21,6 @@ target datalayout = "p:32:32"
 
 ; CHECK: @D = global i1 icmp eq (i64* getelementptr inbounds (i64* @A, i64 1), i64* getelementptr inbounds (i64* @B, i64 2))
 @D = global i1 icmp eq (i64* getelementptr inbounds (i64* @A, i64 1), i64* getelementptr inbounds (i64* @B, i64 2))
+
+; CHECK: @E = global i64 addrspace(1)* addrspacecast (i64* @A to i64 addrspace(1)*)
+@E = global i64 addrspace(1)* addrspacecast(i64* @A to i64 addrspace(1)*)
diff --git a/test/CodeGen/X86/atomic-dagsched.ll b/test/CodeGen/X86/atomic-dagsched.ll
index 05e630b..aa05757 100644
--- a/test/CodeGen/X86/atomic-dagsched.ll
+++ b/test/CodeGen/X86/atomic-dagsched.ll
@@ -34,8 +34,8 @@ dim_0_vector_pre_head.i:                          ; preds = %loop
 vector_kernel_entry.i:                            ; preds = %vector_kernel_entry.i, %dim_0_vector_pre_head.i
   %asr.iv9 = phi i8* [ %scevgep10, %vector_kernel_entry.i ], [ %asr.iv6, %dim_0_vector_pre_head.i ]
   %asr.iv = phi i64 [ %asr.iv.next, %vector_kernel_entry.i ], [ %vector.size.i, %dim_0_vector_pre_head.i ]
-  %8 = bitcast i8* %ptrtoarg4 to i32 addrspace(1)*
-  %asr.iv911 = bitcast i8* %asr.iv9 to <8 x i32> addrspace(1)*
+  %8 = addrspacecast i8* %ptrtoarg4 to i32 addrspace(1)*
+  %asr.iv911 = addrspacecast i8* %asr.iv9 to <8 x i32> addrspace(1)*
   %9 = load <8 x i32> addrspace(1)* %asr.iv911, align 4
   %extract8vector_func.i = extractelement <8 x i32> %9, i32 0
   %extract9vector_func.i = extractelement <8 x i32> %9, i32 1
@@ -73,8 +73,8 @@ dim_0_pre_head.i:                                 ; preds = %scalarIf.i
 
 scalar_kernel_entry.i:                            ; preds = %scalar_kernel_entry.i, %dim_0_pre_head.i
   %asr.iv12 = phi i64 [ %asr.iv.next13, %scalar_kernel_entry.i ], [ %22, %dim_0_pre_head.i ]
-  %23 = bitcast i8* %asr.iv6 to i32 addrspace(1)*
-  %24 = bitcast i8* %ptrtoarg4 to i32 addrspace(1)*
+  %23 = addrspacecast i8* %asr.iv6 to i32 addrspace(1)*
+  %24 = addrspacecast i8* %ptrtoarg4 to i32 addrspace(1)*
   %scevgep16 = getelementptr i32 addrspace(1)* %23, i64 %asr.iv12
   %25 = load i32 addrspace(1)* %scevgep16, align 4
   %26 = atomicrmw min i32 addrspace(1)* %24, i32 %25 seq_cst
diff --git a/test/DebugInfo/X86/dbg-value-isel.ll b/test/DebugInfo/X86/dbg-value-isel.ll
index fa74d61..fed8663 100644
--- a/test/DebugInfo/X86/dbg-value-isel.ll
+++ b/test/DebugInfo/X86/dbg-value-isel.ll
@@ -9,7 +9,7 @@ target triple = "x86_64-apple-darwin10.0.0"
 @sgv = internal addrspace(2) constant [1 x i8] zeroinitializer
 @fgv = internal addrspace(2) constant [1 x i8] zeroinitializer
 @lvgv = internal constant [0 x i8*] zeroinitializer
-@llvm.global.annotations = appending global [1 x %0] [%0 { i8* bitcast (void (i32 addrspace(1)*)* @__OpenCL_nbt02_kernel to i8*), i8* bitcast ([1 x i8] addrspace(2)* @sgv to i8*), i8* bitcast ([1 x i8] addrspace(2)* @fgv to i8*), i8* bitcast ([0 x i8*]* @lvgv to i8*), i32 0 }], section "llvm.metadata"
+@llvm.global.annotations = appending global [1 x %0] [%0 { i8* bitcast (void (i32 addrspace(1)*)* @__OpenCL_nbt02_kernel to i8*), i8* addrspacecast ([1 x i8] addrspace(2)* @sgv to i8*), i8* addrspacecast ([1 x i8] addrspace(2)* @fgv to i8*), i8* bitcast ([0 x i8*]* @lvgv to i8*), i32 0 }], section "llvm.metadata"
 
 define void @__OpenCL_nbt02_kernel(i32 addrspace(1)* %ip) nounwind {
 entry:
diff --git a/test/Feature/newcasts.ll b/test/Feature/newcasts.ll
index 4cfc8bc..dd47484 100644
--- a/test/Feature/newcasts.ll
+++ b/test/Feature/newcasts.ll
@@ -20,6 +20,9 @@ define void @"NewCasts" (i16 %x) {
   %p = uitofp <4 x i32> %n to <4 x float>
   %q = fptosi <4 x float> %p to <4 x i32>
   %r = fptoui <4 x float> %p to <4 x i32>
+  %s = inttoptr <4 x i32> %n to <4 x i32*>
+  %t = addrspacecast <4 x i32*> %s to <4 x i32 addrspace(1)*>
+  %z = addrspacecast <4 x i32*> %s to <4 x float addrspace(2)*>
   ret void
 }
 
diff --git a/test/Other/constant-fold-gep.ll b/test/Other/constant-fold-gep.ll
index 44b6628..aed4145 100644
--- a/test/Other/constant-fold-gep.ll
+++ b/test/Other/constant-fold-gep.ll
@@ -454,10 +454,10 @@ define i32* @fZ() nounwind {
 
 define i8* @different_addrspace() nounwind noinline {
 ; OPT: different_addrspace
-  %p = getelementptr inbounds i8* bitcast ([4 x i8] addrspace(12)* @p12 to i8*),
+  %p = getelementptr inbounds i8* addrspacecast ([4 x i8] addrspace(12)* @p12 to i8*),
                                   i32 2
   ret i8* %p
-; OPT: ret i8* getelementptr (i8* bitcast ([4 x i8] addrspace(12)* @p12 to i8*), i32 2)
+; OPT: ret i8* getelementptr (i8* addrspacecast ([4 x i8] addrspace(12)* @p12 to i8*), i32 2)
 }
 
 define i8* @same_addrspace() nounwind noinline {
diff --git a/test/Transforms/InstCombine/2009-01-16-PointerAddrSpace.ll b/test/Transforms/InstCombine/2009-01-16-PointerAddrSpace.ll
index 949fc59..e354311 100644
--- a/test/Transforms/InstCombine/2009-01-16-PointerAddrSpace.ll
+++ b/test/Transforms/InstCombine/2009-01-16-PointerAddrSpace.ll
@@ -5,7 +5,7 @@ target triple = "i386-apple-darwin9.6"
 
 define i32 @test(i32* %P) nounwind {
 entry:
-  %Q = bitcast i32* %P to i32 addrspace(1)*
+  %Q = addrspacecast i32* %P to i32 addrspace(1)*
   store i32 0, i32 addrspace(1)* %Q, align 4
   ret i32 0
 }
diff --git a/test/Transforms/InstCombine/2012-07-30-addrsp-bitcast.ll b/test/Transforms/InstCombine/2012-07-30-addrsp-bitcast.ll
index 6f3df5b..4d185bf 100644
--- a/test/Transforms/InstCombine/2012-07-30-addrsp-bitcast.ll
+++ b/test/Transforms/InstCombine/2012-07-30-addrsp-bitcast.ll
@@ -1,10 +1,10 @@
 ; RUN: opt < %s -instcombine -S | FileCheck %s
-; CHECK: bitcast
+; CHECK: addrspacecast
 
 @base = internal addrspace(3) unnamed_addr global [16 x i32] zeroinitializer, align 16
 declare void @foo(i32*)
 
 define void @test() nounwind {
-  call void @foo(i32* getelementptr (i32* bitcast ([16 x i32] addrspace(3)* @base to i32*), i64 2147483647)) nounwind
+  call void @foo(i32* getelementptr (i32* addrspacecast ([16 x i32] addrspace(3)* @base to i32*), i64 2147483647)) nounwind
   ret void
 }
diff --git a/test/Transforms/InstCombine/cast_ptr.ll b/test/Transforms/InstCombine/cast_ptr.ll
index d415810..23006a8 100644
--- a/test/Transforms/InstCombine/cast_ptr.ll
+++ b/test/Transforms/InstCombine/cast_ptr.ll
@@ -100,7 +100,7 @@ define %unop* @test5(%op* %O) {
 
 define i8 @test6(i8 addrspace(1)* %source) {
 entry:
-  %arrayidx223 = bitcast i8 addrspace(1)* %source to i8*
+  %arrayidx223 = addrspacecast i8 addrspace(1)* %source to i8*
   %tmp4 = load i8* %arrayidx223
   ret i8 %tmp4
 ; CHECK-LABEL: @test6(
diff --git a/test/Transforms/InstCombine/constant-fold-address-space-pointer.ll b/test/Transforms/InstCombine/constant-fold-address-space-pointer.ll
index f3a474a..9f21d54 100644
--- a/test/Transforms/InstCombine/constant-fold-address-space-pointer.ll
+++ b/test/Transforms/InstCombine/constant-fold-address-space-pointer.ll
@@ -32,10 +32,10 @@ define i32 addrspace(2)* @test_constant_fold_inttoptr_as_pointer_smaller() {
 }
 
 ; Different address spaces that are the same size, but they are
-; different so there should be a bitcast.
+; different so nothing should happen
 define i32 addrspace(4)* @test_constant_fold_inttoptr_as_pointer_smaller_different_as() {
 ; CHECK-LABEL: @test_constant_fold_inttoptr_as_pointer_smaller_different_as(
-; CHECK-NEXT: ret i32 addrspace(4)* bitcast (i32 addrspace(3)* @const_zero_i32_as3 to i32 addrspace(4)*)
+; CHECK-NEXT: ret i32 addrspace(4)* inttoptr (i16 ptrtoint (i32 addrspace(3)* @const_zero_i32_as3 to i16) to i32 addrspace(4)*)
   %x = ptrtoint i32 addrspace(3)* @const_zero_i32_as3 to i16
   %y = inttoptr i16 %x to i32 addrspace(4)*
   ret i32 addrspace(4)* %y
diff --git a/test/Transforms/InstCombine/gep-addrspace.ll b/test/Transforms/InstCombine/gep-addrspace.ll
index dfe12db..24c355d 100644
--- a/test/Transforms/InstCombine/gep-addrspace.ll
+++ b/test/Transforms/InstCombine/gep-addrspace.ll
@@ -9,7 +9,7 @@ target triple = "x86_64-pc-win32"
 define void @func(%myStruct addrspace(1)* nocapture %p) nounwind {
 ST:
   %A = getelementptr inbounds %myStruct addrspace(1)* %p, i64 0
-  %B = bitcast %myStruct addrspace(1)* %A to %myStruct*
+  %B = addrspacecast %myStruct addrspace(1)* %A to %myStruct*
   %C = getelementptr inbounds %myStruct* %B, i32 0, i32 1
   %D = getelementptr inbounds [3 x float]* %C, i32 0, i32 2
   %E = load float* %D, align 4
diff --git a/test/Transforms/InstCombine/objsize-address-space.ll b/test/Transforms/InstCombine/objsize-address-space.ll
index e3723ce..9cb6884 100644
--- a/test/Transforms/InstCombine/objsize-address-space.ll
+++ b/test/Transforms/InstCombine/objsize-address-space.ll
@@ -49,7 +49,7 @@ define i32 @array_as2_size() {
 define i32 @pointer_array_as1() {
 ; CHECK-LABEL: @pointer_array_as1(
 ; CHECK-NEXT: ret i32 80
-  %bc = bitcast [10 x i32 addrspace(1)*]* @array_as1_pointers to i8 addrspace(1)*
+  %bc = addrspacecast [10 x i32 addrspace(1)*]* @array_as1_pointers to i8 addrspace(1)*
   %1 = call i32 @llvm.objectsize.i32.p1i8(i8 addrspace(1)* %bc, i1 false)
   ret i32 %1
 }
diff --git a/unittests/IR/InstructionsTest.cpp b/unittests/IR/InstructionsTest.cpp
index ce6c465..65f85ba 100644
--- a/unittests/IR/InstructionsTest.cpp
+++ b/unittests/IR/InstructionsTest.cpp
@@ -149,6 +149,8 @@ TEST(InstructionsTest, CastInst) {
   const Constant* c8 = Constant::getNullValue(V8x8Ty);
   const Constant* c64 = Constant::getNullValue(V8x64Ty);
 
+  const Constant *v2ptr32 = Constant::getNullValue(V2Int32PtrTy);
+
   EXPECT_TRUE(CastInst::isCastable(V8x8Ty, X86MMXTy));
   EXPECT_TRUE(CastInst::isCastable(X86MMXTy, V8x8Ty));
   EXPECT_FALSE(CastInst::isCastable(Int64Ty, X86MMXTy));
@@ -169,6 +171,10 @@ TEST(InstructionsTest, CastInst) {
   EXPECT_FALSE(CastInst::isBitCastable(V2Int32PtrTy, V2Int32PtrAS1Ty));
   EXPECT_FALSE(CastInst::isBitCastable(V2Int32PtrAS1Ty, V2Int32PtrTy));
   EXPECT_TRUE(CastInst::isBitCastable(V2Int32PtrAS1Ty, V2Int64PtrAS1Ty));
+  EXPECT_TRUE(CastInst::isCastable(V2Int32PtrAS1Ty, V2Int32PtrTy));
+  EXPECT_EQ(CastInst::AddrSpaceCast, CastInst::getCastOpcode(v2ptr32, true,
+                                                             V2Int32PtrAS1Ty,
+                                                             true));
 
   // Test mismatched number of elements for pointers
   EXPECT_FALSE(CastInst::isBitCastable(V2Int32PtrAS1Ty, V4Int64PtrAS1Ty));
@@ -371,7 +377,6 @@ TEST(InstructionsTest, isEliminableCastPair) {
                                            0, Int32Ty, 0),
             0U);
 
-
   // Test that we don't eliminate bitcasts between different address spaces,
   // or if we don't have available pointer size information.
   DataLayout DL("e-p:32:32:32-p1:16:16:16-p2:64:64:64-i1:8:8-i8:8:8-i16:16:16"
@@ -384,26 +389,18 @@ TEST(InstructionsTest, isEliminableCastPair) {
   IntegerType *Int16SizePtr = DL.getIntPtrType(C, 1);
   IntegerType *Int64SizePtr = DL.getIntPtrType(C, 2);
 
-  // Fail since the ptr int types are not provided
+  // Cannot simplify inttoptr, addrspacecast
   EXPECT_EQ(CastInst::isEliminableCastPair(CastInst::IntToPtr,
-                                           CastInst::BitCast,
+                                           CastInst::AddrSpaceCast,
                                            Int16Ty, Int64PtrTyAS1, Int64PtrTyAS2,
-                                           0, 0, 0),
-            0U);
-
-  // Fail since the the bitcast is between different sized address spaces
-  EXPECT_EQ(CastInst::isEliminableCastPair(
-              CastInst::IntToPtr,
-              CastInst::BitCast,
-              Int16Ty, Int64PtrTyAS1, Int64PtrTyAS2,
-              0, Int16SizePtr, Int64SizePtr),
+                                           0, Int16SizePtr, Int64SizePtr),
             0U);
 
-  // Fail since the the bitcast is between different sized address spaces
-  EXPECT_EQ(CastInst::isEliminableCastPair(CastInst::IntToPtr,
-                                           CastInst::BitCast,
-                                           Int16Ty, Int64PtrTyAS1, Int64PtrTyAS2,
-                                           0, Int16SizePtr, Int64SizePtr),
+  // Cannot simplify addrspacecast, ptrtoint
+  EXPECT_EQ(CastInst::isEliminableCastPair(CastInst::AddrSpaceCast,
+                                           CastInst::PtrToInt,
+                                           Int64PtrTyAS1, Int64PtrTyAS2, Int16Ty,
+                                           Int64SizePtr, Int16SizePtr, 0),
             0U);
 
   // Pass since the bitcast address spaces are the same
@@ -413,28 +410,6 @@ TEST(InstructionsTest, isEliminableCastPair) {
                                            0, 0, 0),
             CastInst::IntToPtr);
 
-
-  // Fail without known pointer sizes and different address spaces
-  EXPECT_EQ(CastInst::isEliminableCastPair(CastInst::BitCast,
-                                           CastInst::PtrToInt,
-                                           Int64PtrTyAS1, Int64PtrTyAS2, Int16Ty,
-                                           0, 0, 0),
-            0U);
-
-  // Pass since the address spaces are the same, even though the pointer sizes
-  // are unknown
-  EXPECT_EQ(CastInst::isEliminableCastPair(CastInst::BitCast,
-                                           CastInst::PtrToInt,
-                                           Int64PtrTyAS1, Int64PtrTyAS1, Int32Ty,
-                                           0, 0, 0),
-            Instruction::PtrToInt);
-
-  // Fail since the bitcast is the wrong size
-  EXPECT_EQ(CastInst::isEliminableCastPair(CastInst::BitCast,
-                                           CastInst::PtrToInt,
-                                           Int64PtrTyAS1, Int64PtrTyAS2, Int64Ty,
-                                           Int16SizePtr, Int64SizePtr, 0),
-            0U);
 }
 
 }  // end anonymous namespace
diff --git a/utils/emacs/llvm-mode.el b/utils/emacs/llvm-mode.el
index 3b8fbd7..99d3294 100644
--- a/utils/emacs/llvm-mode.el
+++ b/utils/emacs/llvm-mode.el
@@ -43,7 +43,7 @@
    ;; Memory operators
    `(,(regexp-opt '("malloc" "alloca" "free" "load" "store" "getelementptr" "fence" "cmpxchg" "atomicrmw") 'words) . font-lock-keyword-face)
    ;; Casts
-   `(,(regexp-opt '("bitcast" "inttoptr" "ptrtoint" "trunc" "zext" "sext" "fptrunc" "fpext" "fptoui" "fptosi" "uitofp" "sitofp") 'words) . font-lock-keyword-face)
+   `(,(regexp-opt '("bitcast" "inttoptr" "ptrtoint" "trunc" "zext" "sext" "fptrunc" "fpext" "fptoui" "fptosi" "uitofp" "sitofp" "addrspacecast") 'words) . font-lock-keyword-face)
    ;; Vector ops
    `(,(regexp-opt '("extractelement" "insertelement" "shufflevector") 'words) . font-lock-keyword-face)
    ;; Aggregate ops
diff --git a/utils/kate/llvm.xml b/utils/kate/llvm.xml
index 7cea92a..dfacfb5 100644
--- a/utils/kate/llvm.xml
+++ b/utils/kate/llvm.xml
@@ -157,6 +157,7 @@
       <item> ptrtoint </item>
       <item> inttoptr </item>
       <item> bitcast </item>
+      <item> addrspacecast </item>
       <item> icmp </item>
       <item> fcmp </item>
       <item> phi </item>
diff --git a/utils/vim/llvm.vim b/utils/vim/llvm.vim
index c611ad8..c2ec57c 100644
--- a/utils/vim/llvm.vim
+++ b/utils/vim/llvm.vim
@@ -22,17 +22,18 @@ syn match   llvmType /\<i\d\+\>/
 " Instructions.
 " The true and false tokens can be used for comparison opcodes, but it's
 " much more common for these tokens to be used for boolean constants.
-syn keyword llvmStatement add alloca and arcp ashr atomicrmw bitcast br call
-syn keyword llvmStatement cmpxchg eq exact extractelement extractvalue fadd fast
-syn keyword llvmStatement fcmp fdiv fence fmul fpext fptosi fptoui fptrunc free
-syn keyword llvmStatement frem fsub getelementptr icmp inbounds indirectbr
-syn keyword llvmStatement insertelement insertvalue inttoptr invoke landingpad
-syn keyword llvmStatement load lshr malloc max min mul nand ne ninf nnan nsw nsz
-syn keyword llvmStatement nuw oeq oge ogt ole olt one or ord phi ptrtoint resume
-syn keyword llvmStatement ret sdiv select sext sge sgt shl shufflevector sitofp
-syn keyword llvmStatement sle slt srem store sub switch trunc udiv ueq uge ugt
-syn keyword llvmStatement uitofp ule ult umax umin une uno unreachable unwind
-syn keyword llvmStatement urem va_arg xchg xor zext
+syn keyword llvmStatement add addrspacecast alloca and arcp ashr atomicrmw
+syn keyword llvmStatement bitcast br call cmpxchg eq exact extractelement
+syn keyword llvmStatement extractvalue fadd fast fcmp fdiv fence fmul fpext
+syn keyword llvmStatement fptosi fptoui fptrunc free frem fsub getelementptr
+syn keyword llvmStatement icmp inbounds indirectbr insertelement insertvalue
+syn keyword llvmStatement inttoptr invoke landingpad load lshr malloc max min
+syn keyword llvmStatement mul nand ne ninf nnan nsw nsz nuw oeq oge ogt ole
+syn keyword llvmStatement olt one or ord phi ptrtoint resume ret sdiv select
+syn keyword llvmStatement sext sge sgt shl shufflevector sitofp sle slt srem
+syn keyword llvmStatement store sub switch trunc udiv ueq uge ugt uitofp ule ult
+syn keyword llvmStatement umax umin une uno unreachable unwind urem va_arg
+syn keyword llvmStatement xchg xor zext
 
 " Keywords.
 syn keyword llvmKeyword acq_rel acquire sanitize_address addrspace alias align