Factor out TargetABIInfo stuff into separate file. No functionality change.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@72962 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 1398 insertions, 1382 deletions

diff --git a/lib/CodeGen/ABIInfo.h b/lib/CodeGen/ABIInfo.h
index 3de461242a..44af0c476a 100644
--- a/lib/CodeGen/ABIInfo.h
+++ b/lib/CodeGen/ABIInfo.h
@@ -10,8 +10,13 @@
 #ifndef CLANG_CODEGEN_ABIINFO_H
 #define CLANG_CODEGEN_ABIINFO_H
 
+#include "clang/AST/Type.h"
+
+#include <cassert>
+
 namespace llvm {
   class Type;
+  class Value;
 }
 
 namespace clang {
@@ -38,32 +43,32 @@ namespace clang {
       Direct,    /// Pass the argument directly using the normal
                  /// converted LLVM type. Complex and structure types
                  /// are passed using first class aggregates.
-  
+
       Indirect,  /// Pass the argument indirectly via a hidden pointer
                  /// with the specified alignment (0 indicates default
                  /// alignment).
-  
+
       Ignore,    /// Ignore the argument (treat as void). Useful for
                  /// void and empty structs.
-  
+
       Coerce,    /// Only valid for aggregate return types, the argument
                  /// should be accessed by coercion to a provided type.
-  
+
       Expand,    /// Only valid for aggregate argument types. The
                  /// structure should be expanded into consecutive
                  /// arguments for its constituent fields. Currently
                  /// expand is only allowed on structures whose fields
                  /// are all scalar types or are themselves expandable
                  /// types.
-  
+
       KindFirst=Direct, KindLast=Expand
     };
-  
+
   private:
     Kind TheKind;
     const llvm::Type *TypeData;
     unsigned UIntData;
-  
+
     ABIArgInfo(Kind K, const llvm::Type *TD=0,
                unsigned UI=0) : TheKind(K),
                                 TypeData(TD),
@@ -71,13 +76,13 @@ namespace clang {
   public:
     ABIArgInfo() : TheKind(Direct), TypeData(0), UIntData(0) {}
 
-    static ABIArgInfo getDirect() { 
-      return ABIArgInfo(Direct); 
+    static ABIArgInfo getDirect() {
+      return ABIArgInfo(Direct);
     }
     static ABIArgInfo getIgnore() {
       return ABIArgInfo(Ignore);
     }
-    static ABIArgInfo getCoerce(const llvm::Type *T) { 
+    static ABIArgInfo getCoerce(const llvm::Type *T) {
       return ABIArgInfo(Coerce, T);
     }
     static ABIArgInfo getIndirect(unsigned Alignment) {
@@ -86,20 +91,20 @@ namespace clang {
     static ABIArgInfo getExpand() {
       return ABIArgInfo(Expand);
     }
-  
+
     Kind getKind() const { return TheKind; }
     bool isDirect() const { return TheKind == Direct; }
     bool isIgnore() const { return TheKind == Ignore; }
     bool isCoerce() const { return TheKind == Coerce; }
     bool isIndirect() const { return TheKind == Indirect; }
     bool isExpand() const { return TheKind == Expand; }
-  
+
     // Coerce accessors
     const llvm::Type *getCoerceToType() const {
       assert(TheKind == Coerce && "Invalid kind!");
       return TypeData;
     }
-  
+
     // ByVal accessors
     unsigned getIndirectAlign() const {
       assert(TheKind == Indirect && "Invalid kind!");
@@ -120,7 +125,7 @@ namespace clang {
 
     /// EmitVAArg - Emit the target dependent code to load a value of
     /// \arg Ty from the va_list pointed to by \arg VAListAddr.
-    
+
     // FIXME: This is a gaping layering violation if we wanted to drop
     // the ABI information any lower than CodeGen. Of course, for
     // VAArg handling it has to be at this level; there is no way to
diff --git a/lib/CodeGen/CGCall.cpp b/lib/CodeGen/CGCall.cpp
index 55601f38db..b46e860b2e 100644
--- a/lib/CodeGen/CGCall.cpp
+++ b/lib/CodeGen/CGCall.cpp
@@ -16,16 +16,12 @@
 #include "CodeGenFunction.h"
 #include "CodeGenModule.h"
 #include "clang/Basic/TargetInfo.h"
-#include "clang/AST/ASTContext.h"
 #include "clang/AST/Decl.h"
 #include "clang/AST/DeclCXX.h"
 #include "clang/AST/DeclObjC.h"
-#include "clang/AST/RecordLayout.h"
 #include "clang/Frontend/CompileOptions.h"
-#include "llvm/ADT/StringExtras.h"
 #include "llvm/Attributes.h"
 #include "llvm/Support/CallSite.h"
-#include "llvm/Support/MathExtras.h"
 #include "llvm/Target/TargetData.h"
 
 #include "ABIInfo.h"
@@ -127,1370 +123,6 @@ const CGFunctionInfo &CodeGenTypes::getFunctionInfo(QualType ResTy,
   return *FI;
 }
 
-/***/
-
-ABIInfo::~ABIInfo() {}
-
-void ABIArgInfo::dump() const {
-  fprintf(stderr, "(ABIArgInfo Kind=");
-  switch (TheKind) {
-  case Direct: 
-    fprintf(stderr, "Direct");
-    break;
-  case Ignore: 
-    fprintf(stderr, "Ignore");
-    break;
-  case Coerce: 
-    fprintf(stderr, "Coerce Type=");
-    getCoerceToType()->print(llvm::errs());
-    break;
-  case Indirect: 
-    fprintf(stderr, "Indirect Align=%d", getIndirectAlign());
-    break;
-  case Expand: 
-    fprintf(stderr, "Expand");
-    break;
-  }
-  fprintf(stderr, ")\n");
-}
-
-/***/
-
-static bool isEmptyRecord(ASTContext &Context, QualType T);
-
-/// isEmptyField - Return true iff a the field is "empty", that is it
-/// is an unnamed bit-field or an (array of) empty record(s).
-static bool isEmptyField(ASTContext &Context, const FieldDecl *FD) {
-  if (FD->isUnnamedBitfield())
-    return true;
-
-  QualType FT = FD->getType();
-  // Constant arrays of empty records count as empty, strip them off.
-  while (const ConstantArrayType *AT = Context.getAsConstantArrayType(FT))
-    FT = AT->getElementType();
-  
-  return isEmptyRecord(Context, FT);
-}
-
-/// isEmptyRecord - Return true iff a structure contains only empty
-/// fields. Note that a structure with a flexible array member is not
-/// considered empty.
-static bool isEmptyRecord(ASTContext &Context, QualType T) {
-  const RecordType *RT = T->getAsRecordType();
-  if (!RT)
-    return 0;
-  const RecordDecl *RD = RT->getDecl();
-  if (RD->hasFlexibleArrayMember())
-    return false;
-  for (RecordDecl::field_iterator i = RD->field_begin(Context), 
-         e = RD->field_end(Context); i != e; ++i)
-    if (!isEmptyField(Context, *i))
-      return false;
-  return true;
-}
-
-/// isSingleElementStruct - Determine if a structure is a "single
-/// element struct", i.e. it has exactly one non-empty field or
-/// exactly one field which is itself a single element
-/// struct. Structures with flexible array members are never
-/// considered single element structs.
-///
-/// \return The field declaration for the single non-empty field, if
-/// it exists.
-static const Type *isSingleElementStruct(QualType T, ASTContext &Context) {
-  const RecordType *RT = T->getAsStructureType();
-  if (!RT)
-    return 0;
-
-  const RecordDecl *RD = RT->getDecl();
-  if (RD->hasFlexibleArrayMember())
-    return 0;
-
-  const Type *Found = 0;
-  for (RecordDecl::field_iterator i = RD->field_begin(Context), 
-         e = RD->field_end(Context); i != e; ++i) {
-    const FieldDecl *FD = *i;
-    QualType FT = FD->getType();
-
-    // Ignore empty fields.
-    if (isEmptyField(Context, FD))
-      continue;
-
-    // If we already found an element then this isn't a single-element
-    // struct.
-    if (Found)
-      return 0;
-
-    // Treat single element arrays as the element.
-    while (const ConstantArrayType *AT = Context.getAsConstantArrayType(FT)) {
-      if (AT->getSize().getZExtValue() != 1)
-        break;
-      FT = AT->getElementType();
-    }
-
-    if (!CodeGenFunction::hasAggregateLLVMType(FT)) {
-      Found = FT.getTypePtr();
-    } else {
-      Found = isSingleElementStruct(FT, Context);
-      if (!Found)
-        return 0;
-    }
-  }
-
-  return Found;
-}
-
-static bool is32Or64BitBasicType(QualType Ty, ASTContext &Context) {
-  if (!Ty->getAsBuiltinType() && !Ty->isPointerType())
-    return false;
-
-  uint64_t Size = Context.getTypeSize(Ty);
-  return Size == 32 || Size == 64;
-}
-
-static bool areAllFields32Or64BitBasicType(const RecordDecl *RD,
-                                           ASTContext &Context) {
-  for (RecordDecl::field_iterator i = RD->field_begin(Context), 
-         e = RD->field_end(Context); i != e; ++i) {
-    const FieldDecl *FD = *i;
-
-    if (!is32Or64BitBasicType(FD->getType(), Context))
-      return false;
-    
-    // FIXME: Reject bit-fields wholesale; there are two problems, we don't know
-    // how to expand them yet, and the predicate for telling if a bitfield still
-    // counts as "basic" is more complicated than what we were doing previously.
-    if (FD->isBitField())
-      return false;
-  }
-
-  return true;
-}
-
-namespace {
-/// DefaultABIInfo - The default implementation for ABI specific
-/// details. This implementation provides information which results in
-/// self-consistent and sensible LLVM IR generation, but does not
-/// conform to any particular ABI.
-class DefaultABIInfo : public ABIInfo {
-  ABIArgInfo classifyReturnType(QualType RetTy, 
-                                ASTContext &Context) const;
-  
-  ABIArgInfo classifyArgumentType(QualType RetTy,
-                                  ASTContext &Context) const;
-
-  virtual void computeInfo(CGFunctionInfo &FI, ASTContext &Context) const {
-    FI.getReturnInfo() = classifyReturnType(FI.getReturnType(), Context);
-    for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
-         it != ie; ++it)
-      it->info = classifyArgumentType(it->type, Context);
-  }
-
-  virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
-                                 CodeGenFunction &CGF) const;
-};
-
-/// X86_32ABIInfo - The X86-32 ABI information.
-class X86_32ABIInfo : public ABIInfo {
-  ASTContext &Context;
-  bool IsDarwin;
-
-  static bool isRegisterSize(unsigned Size) {
-    return (Size == 8 || Size == 16 || Size == 32 || Size == 64);
-  }
-
-  static bool shouldReturnTypeInRegister(QualType Ty, ASTContext &Context);
-
-public:
-  ABIArgInfo classifyReturnType(QualType RetTy, 
-                                ASTContext &Context) const;
-
-  ABIArgInfo classifyArgumentType(QualType RetTy,
-                                  ASTContext &Context) const;
-
-  virtual void computeInfo(CGFunctionInfo &FI, ASTContext &Context) const {
-    FI.getReturnInfo() = classifyReturnType(FI.getReturnType(), Context);
-    for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
-         it != ie; ++it)
-      it->info = classifyArgumentType(it->type, Context);
-  }
-
-  virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
-                                 CodeGenFunction &CGF) const;
-
-  X86_32ABIInfo(ASTContext &Context, bool d) 
-    : ABIInfo(), Context(Context), IsDarwin(d) {}
-};
-}
-
-
-/// shouldReturnTypeInRegister - Determine if the given type should be
-/// passed in a register (for the Darwin ABI).
-bool X86_32ABIInfo::shouldReturnTypeInRegister(QualType Ty,
-                                               ASTContext &Context) {
-  uint64_t Size = Context.getTypeSize(Ty);
-
-  // Type must be register sized.
-  if (!isRegisterSize(Size))
-    return false;
-
-  if (Ty->isVectorType()) {
-    // 64- and 128- bit vectors inside structures are not returned in
-    // registers.
-    if (Size == 64 || Size == 128)
-      return false;
-
-    return true;
-  }
-
-  // If this is a builtin, pointer, or complex type, it is ok.
-  if (Ty->getAsBuiltinType() || Ty->isPointerType() || Ty->isAnyComplexType())
-    return true;
-
-  // Arrays are treated like records.
-  if (const ConstantArrayType *AT = Context.getAsConstantArrayType(Ty))
-    return shouldReturnTypeInRegister(AT->getElementType(), Context);
-
-  // Otherwise, it must be a record type.
-  const RecordType *RT = Ty->getAsRecordType();
-  if (!RT) return false;
-
-  // Structure types are passed in register if all fields would be
-  // passed in a register.
-  for (RecordDecl::field_iterator i = RT->getDecl()->field_begin(Context), 
-         e = RT->getDecl()->field_end(Context); i != e; ++i) {
-    const FieldDecl *FD = *i;
-    
-    // Empty fields are ignored.
-    if (isEmptyField(Context, FD))
-      continue;
-
-    // Check fields recursively.
-    if (!shouldReturnTypeInRegister(FD->getType(), Context))
-      return false;
-  }
-
-  return true;
-}
-
-ABIArgInfo X86_32ABIInfo::classifyReturnType(QualType RetTy,
-                                            ASTContext &Context) const {
-  if (RetTy->isVoidType()) {
-    return ABIArgInfo::getIgnore();
-  } else if (const VectorType *VT = RetTy->getAsVectorType()) {
-    // On Darwin, some vectors are returned in registers.
-    if (IsDarwin) {
-      uint64_t Size = Context.getTypeSize(RetTy);
-
-      // 128-bit vectors are a special case; they are returned in
-      // registers and we need to make sure to pick a type the LLVM
-      // backend will like.
-      if (Size == 128)
-        return ABIArgInfo::getCoerce(llvm::VectorType::get(llvm::Type::Int64Ty, 
-                                                           2));
-
-      // Always return in register if it fits in a general purpose
-      // register, or if it is 64 bits and has a single element.
-      if ((Size == 8 || Size == 16 || Size == 32) ||
-          (Size == 64 && VT->getNumElements() == 1))
-        return ABIArgInfo::getCoerce(llvm::IntegerType::get(Size));
-        
-      return ABIArgInfo::getIndirect(0);
-    }
-
-    return ABIArgInfo::getDirect();
-  } else if (CodeGenFunction::hasAggregateLLVMType(RetTy)) {
-    // Structures with flexible arrays are always indirect.
-    if (const RecordType *RT = RetTy->getAsStructureType())
-      if (RT->getDecl()->hasFlexibleArrayMember())
-        return ABIArgInfo::getIndirect(0);
-
-    // Outside of Darwin, structs and unions are always indirect.
-    if (!IsDarwin && !RetTy->isAnyComplexType())
-      return ABIArgInfo::getIndirect(0);
-
-    // Classify "single element" structs as their element type.
-    if (const Type *SeltTy = isSingleElementStruct(RetTy, Context)) {
-      if (const BuiltinType *BT = SeltTy->getAsBuiltinType()) {
-        if (BT->isIntegerType()) {
-          // We need to use the size of the structure, padding
-          // bit-fields can adjust that to be larger than the single
-          // element type.
-          uint64_t Size = Context.getTypeSize(RetTy);
-          return ABIArgInfo::getCoerce(llvm::IntegerType::get((unsigned) Size));
-        } else if (BT->getKind() == BuiltinType::Float) {
-          assert(Context.getTypeSize(RetTy) == Context.getTypeSize(SeltTy) &&
-                 "Unexpect single element structure size!");
-          return ABIArgInfo::getCoerce(llvm::Type::FloatTy);
-        } else if (BT->getKind() == BuiltinType::Double) {
-          assert(Context.getTypeSize(RetTy) == Context.getTypeSize(SeltTy) &&
-                 "Unexpect single element structure size!");
-          return ABIArgInfo::getCoerce(llvm::Type::DoubleTy);
-        }
-      } else if (SeltTy->isPointerType()) {
-        // FIXME: It would be really nice if this could come out as the proper
-        // pointer type.
-        llvm::Type *PtrTy = 
-          llvm::PointerType::getUnqual(llvm::Type::Int8Ty);
-        return ABIArgInfo::getCoerce(PtrTy);
-      } else if (SeltTy->isVectorType()) {
-        // 64- and 128-bit vectors are never returned in a
-        // register when inside a structure.
-        uint64_t Size = Context.getTypeSize(RetTy);
-        if (Size == 64 || Size == 128)
-          return ABIArgInfo::getIndirect(0);
-
-        return classifyReturnType(QualType(SeltTy, 0), Context);
-      }
-    }
-
-    // Small structures which are register sized are generally returned
-    // in a register.
-    if (X86_32ABIInfo::shouldReturnTypeInRegister(RetTy, Context)) {
-      uint64_t Size = Context.getTypeSize(RetTy);
-      return ABIArgInfo::getCoerce(llvm::IntegerType::get(Size));
-    }
-
-    return ABIArgInfo::getIndirect(0);
-  } else {
-    return ABIArgInfo::getDirect();
-  }
-}
-
-ABIArgInfo X86_32ABIInfo::classifyArgumentType(QualType Ty,
-                                               ASTContext &Context) const {
-  // FIXME: Set alignment on indirect arguments.
-  if (CodeGenFunction::hasAggregateLLVMType(Ty)) {
-    // Structures with flexible arrays are always indirect.
-    if (const RecordType *RT = Ty->getAsStructureType())
-      if (RT->getDecl()->hasFlexibleArrayMember())
-        return ABIArgInfo::getIndirect(0);
-
-    // Ignore empty structs.
-    uint64_t Size = Context.getTypeSize(Ty);
-    if (Ty->isStructureType() && Size == 0)
-      return ABIArgInfo::getIgnore();
-
-    // Expand structs with size <= 128-bits which consist only of
-    // basic types (int, long long, float, double, xxx*). This is
-    // non-recursive and does not ignore empty fields.
-    if (const RecordType *RT = Ty->getAsStructureType()) {
-      if (Context.getTypeSize(Ty) <= 4*32 &&
-          areAllFields32Or64BitBasicType(RT->getDecl(), Context))
-        return ABIArgInfo::getExpand();
-    }
-
-    return ABIArgInfo::getIndirect(0);
-  } else {
-    return ABIArgInfo::getDirect();
-  }
-}
-
-llvm::Value *X86_32ABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
-                                      CodeGenFunction &CGF) const {
-  const llvm::Type *BP = llvm::PointerType::getUnqual(llvm::Type::Int8Ty);
-  const llvm::Type *BPP = llvm::PointerType::getUnqual(BP);
-
-  CGBuilderTy &Builder = CGF.Builder;
-  llvm::Value *VAListAddrAsBPP = Builder.CreateBitCast(VAListAddr, BPP, 
-                                                       "ap");
-  llvm::Value *Addr = Builder.CreateLoad(VAListAddrAsBPP, "ap.cur");
-  llvm::Type *PTy = 
-    llvm::PointerType::getUnqual(CGF.ConvertType(Ty));
-  llvm::Value *AddrTyped = Builder.CreateBitCast(Addr, PTy);
-  
-  uint64_t Offset = 
-    llvm::RoundUpToAlignment(CGF.getContext().getTypeSize(Ty) / 8, 4);
-  llvm::Value *NextAddr = 
-    Builder.CreateGEP(Addr, 
-                      llvm::ConstantInt::get(llvm::Type::Int32Ty, Offset),
-                      "ap.next");
-  Builder.CreateStore(NextAddr, VAListAddrAsBPP);
-
-  return AddrTyped;
-}
-
-namespace {
-/// X86_64ABIInfo - The X86_64 ABI information.
-class X86_64ABIInfo : public ABIInfo {
-  enum Class {
-    Integer = 0,
-    SSE,
-    SSEUp,
-    X87,
-    X87Up,
-    ComplexX87,
-    NoClass,
-    Memory
-  };
-
-  /// merge - Implement the X86_64 ABI merging algorithm.
-  ///
-  /// Merge an accumulating classification \arg Accum with a field
-  /// classification \arg Field.
-  ///
-  /// \param Accum - The accumulating classification. This should
-  /// always be either NoClass or the result of a previous merge
-  /// call. In addition, this should never be Memory (the caller
-  /// should just return Memory for the aggregate).
-  Class merge(Class Accum, Class Field) const;
-
-  /// classify - Determine the x86_64 register classes in which the
-  /// given type T should be passed.
-  ///
-  /// \param Lo - The classification for the parts of the type
-  /// residing in the low word of the containing object.
-  ///
-  /// \param Hi - The classification for the parts of the type
-  /// residing in the high word of the containing object.
-  ///
-  /// \param OffsetBase - The bit offset of this type in the
-  /// containing object.  Some parameters are classified different
-  /// depending on whether they straddle an eightbyte boundary.
-  ///
-  /// If a word is unused its result will be NoClass; if a type should
-  /// be passed in Memory then at least the classification of \arg Lo
-  /// will be Memory.
-  ///
-  /// The \arg Lo class will be NoClass iff the argument is ignored.
-  ///
-  /// If the \arg Lo class is ComplexX87, then the \arg Hi class will
-  /// also be ComplexX87.
-  void classify(QualType T, ASTContext &Context, uint64_t OffsetBase,
-                Class &Lo, Class &Hi) const;
-  
-  /// getCoerceResult - Given a source type \arg Ty and an LLVM type
-  /// to coerce to, chose the best way to pass Ty in the same place
-  /// that \arg CoerceTo would be passed, but while keeping the
-  /// emitted code as simple as possible.
-  ///
-  /// FIXME: Note, this should be cleaned up to just take an enumeration of all
-  /// the ways we might want to pass things, instead of constructing an LLVM
-  /// type. This makes this code more explicit, and it makes it clearer that we
-  /// are also doing this for correctness in the case of passing scalar types.
-  ABIArgInfo getCoerceResult(QualType Ty,
-                             const llvm::Type *CoerceTo,
-                             ASTContext &Context) const;
-
-  /// getIndirectResult - Give a source type \arg Ty, return a suitable result
-  /// such that the argument will be passed in memory.
-  ABIArgInfo getIndirectResult(QualType Ty,
-                               ASTContext &Context) const;
-
-  ABIArgInfo classifyReturnType(QualType RetTy, 
-                                ASTContext &Context) const;  
-
-  ABIArgInfo classifyArgumentType(QualType Ty,
-                                  ASTContext &Context,
-                                  unsigned &neededInt,
-                                  unsigned &neededSSE) const;
-
-public:
-  virtual void computeInfo(CGFunctionInfo &FI, ASTContext &Context) const;
-
-  virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
-                                 CodeGenFunction &CGF) const;
-};
-}
-
-X86_64ABIInfo::Class X86_64ABIInfo::merge(Class Accum, 
-                                          Class Field) const {
-  // AMD64-ABI 3.2.3p2: Rule 4. Each field of an object is
-  // classified recursively so that always two fields are
-  // considered. The resulting class is calculated according to
-  // the classes of the fields in the eightbyte:
-  //
-  // (a) If both classes are equal, this is the resulting class.
-  //
-  // (b) If one of the classes is NO_CLASS, the resulting class is
-  // the other class.
-  //
-  // (c) If one of the classes is MEMORY, the result is the MEMORY
-  // class.
-  //
-  // (d) If one of the classes is INTEGER, the result is the
-  // INTEGER.
-  //
-  // (e) If one of the classes is X87, X87UP, COMPLEX_X87 class,
-  // MEMORY is used as class.
-  //
-  // (f) Otherwise class SSE is used.
-
-  // Accum should never be memory (we should have returned) or
-  // ComplexX87 (because this cannot be passed in a structure).
-  assert((Accum != Memory && Accum != ComplexX87) &&
-         "Invalid accumulated classification during merge.");
-  if (Accum == Field || Field == NoClass)
-    return Accum;
-  else if (Field == Memory)
-    return Memory;
-  else if (Accum == NoClass)
-    return Field;
-  else if (Accum == Integer || Field == Integer) 
-    return Integer;
-  else if (Field == X87 || Field == X87Up || Field == ComplexX87 ||
-           Accum == X87 || Accum == X87Up)
-    return Memory;
-  else
-    return SSE;
-}
-
-void X86_64ABIInfo::classify(QualType Ty,
-                             ASTContext &Context,
-                             uint64_t OffsetBase,
-                             Class &Lo, Class &Hi) const {
-  // FIXME: This code can be simplified by introducing a simple value class for
-  // Class pairs with appropriate constructor methods for the various
-  // situations.
-
-  // FIXME: Some of the split computations are wrong; unaligned vectors
-  // shouldn't be passed in registers for example, so there is no chance they
-  // can straddle an eightbyte. Verify & simplify.
-
-  Lo = Hi = NoClass;
-
-  Class &Current = OffsetBase < 64 ? Lo : Hi;
-  Current = Memory;
-
-  if (const BuiltinType *BT = Ty->getAsBuiltinType()) {
-    BuiltinType::Kind k = BT->getKind();
-
-    if (k == BuiltinType::Void) {
-      Current = NoClass; 
-    } else if (k == BuiltinType::Int128 || k == BuiltinType::UInt128) {
-      Lo = Integer;
-      Hi = Integer;
-    } else if (k >= BuiltinType::Bool && k <= BuiltinType::LongLong) {
-      Current = Integer;
-    } else if (k == BuiltinType::Float || k == BuiltinType::Double) {
-      Current = SSE;
-    } else if (k == BuiltinType::LongDouble) {
-      Lo = X87;
-      Hi = X87Up;
-    }
-    // FIXME: _Decimal32 and _Decimal64 are SSE.
-    // FIXME: _float128 and _Decimal128 are (SSE, SSEUp).
-  } else if (const EnumType *ET = Ty->getAsEnumType()) {
-    // Classify the underlying integer type.
-    classify(ET->getDecl()->getIntegerType(), Context, OffsetBase, Lo, Hi);
-  } else if (Ty->hasPointerRepresentation()) {
-    Current = Integer;
-  } else if (const VectorType *VT = Ty->getAsVectorType()) {
-    uint64_t Size = Context.getTypeSize(VT);
-    if (Size == 32) {
-      // gcc passes all <4 x char>, <2 x short>, <1 x int>, <1 x
-      // float> as integer.      
-      Current = Integer;
-
-      // If this type crosses an eightbyte boundary, it should be
-      // split.
-      uint64_t EB_Real = (OffsetBase) / 64;
-      uint64_t EB_Imag = (OffsetBase + Size - 1) / 64;
-      if (EB_Real != EB_Imag)
-        Hi = Lo;      
-    } else if (Size == 64) {
-      // gcc passes <1 x double> in memory. :(
-      if (VT->getElementType()->isSpecificBuiltinType(BuiltinType::Double))
-        return;
-      
-      // gcc passes <1 x long long> as INTEGER.
-      if (VT->getElementType()->isSpecificBuiltinType(BuiltinType::LongLong))
-        Current = Integer;
-      else
-        Current = SSE;
-
-      // If this type crosses an eightbyte boundary, it should be
-      // split.
-      if (OffsetBase && OffsetBase != 64)
-        Hi = Lo;
-    } else if (Size == 128) {
-      Lo = SSE;
-      Hi = SSEUp;
-    }
-  } else if (const ComplexType *CT = Ty->getAsComplexType()) {
-    QualType ET = Context.getCanonicalType(CT->getElementType());
-    
-    uint64_t Size = Context.getTypeSize(Ty);
-    if (ET->isIntegralType()) {
-      if (Size <= 64)
-        Current = Integer;
-      else if (Size <= 128)
-        Lo = Hi = Integer;
-    } else if (ET == Context.FloatTy) 
-      Current = SSE;
-    else if (ET == Context.DoubleTy)
-      Lo = Hi = SSE;
-    else if (ET == Context.LongDoubleTy)
-      Current = ComplexX87;
-
-    // If this complex type crosses an eightbyte boundary then it
-    // should be split.
-    uint64_t EB_Real = (OffsetBase) / 64;
-    uint64_t EB_Imag = (OffsetBase + Context.getTypeSize(ET)) / 64;
-    if (Hi == NoClass && EB_Real != EB_Imag)
-      Hi = Lo;
-  } else if (const ConstantArrayType *AT = Context.getAsConstantArrayType(Ty)) {
-    // Arrays are treated like structures.
-
-    uint64_t Size = Context.getTypeSize(Ty);
-    
-    // AMD64-ABI 3.2.3p2: Rule 1. If the size of an object is larger
-    // than two eightbytes, ..., it has class MEMORY.
-    if (Size > 128)
-      return;
-    
-    // AMD64-ABI 3.2.3p2: Rule 1. If ..., or it contains unaligned
-    // fields, it has class MEMORY.
-    //
-    // Only need to check alignment of array base.
-    if (OffsetBase % Context.getTypeAlign(AT->getElementType()))
-      return;
-
-    // Otherwise implement simplified merge. We could be smarter about
-    // this, but it isn't worth it and would be harder to verify.
-    Current = NoClass;
-    uint64_t EltSize = Context.getTypeSize(AT->getElementType());
-    uint64_t ArraySize = AT->getSize().getZExtValue();
-    for (uint64_t i=0, Offset=OffsetBase; i<ArraySize; ++i, Offset += EltSize) {
-      Class FieldLo, FieldHi;
-      classify(AT->getElementType(), Context, Offset, FieldLo, FieldHi);
-      Lo = merge(Lo, FieldLo);
-      Hi = merge(Hi, FieldHi);
-      if (Lo == Memory || Hi == Memory)
-        break;
-    }
-    
-    // Do post merger cleanup (see below). Only case we worry about is Memory.
-    if (Hi == Memory)
-      Lo = Memory;
-    assert((Hi != SSEUp || Lo == SSE) && "Invalid SSEUp array classification.");
-  } else if (const RecordType *RT = Ty->getAsRecordType()) {
-    uint64_t Size = Context.getTypeSize(Ty);
-    
-    // AMD64-ABI 3.2.3p2: Rule 1. If the size of an object is larger
-    // than two eightbytes, ..., it has class MEMORY.
-    if (Size > 128)
-      return;
-
-    const RecordDecl *RD = RT->getDecl();
-
-    // Assume variable sized types are passed in memory.
-    if (RD->hasFlexibleArrayMember())
-      return;
-
-    const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
-    
-    // Reset Lo class, this will be recomputed.
-    Current = NoClass;
-    unsigned idx = 0;
-    for (RecordDecl::field_iterator i = RD->field_begin(Context), 
-           e = RD->field_end(Context); i != e; ++i, ++idx) {
-      uint64_t Offset = OffsetBase + Layout.getFieldOffset(idx);
-      bool BitField = i->isBitField();
-
-      // AMD64-ABI 3.2.3p2: Rule 1. If ..., or it contains unaligned
-      // fields, it has class MEMORY.
-      //
-      // Note, skip this test for bit-fields, see below.
-      if (!BitField && Offset % Context.getTypeAlign(i->getType())) {
-        Lo = Memory;
-        return;
-      }
-
-      // Classify this field.
-      //
-      // AMD64-ABI 3.2.3p2: Rule 3. If the size of the aggregate
-      // exceeds a single eightbyte, each is classified
-      // separately. Each eightbyte gets initialized to class
-      // NO_CLASS.
-      Class FieldLo, FieldHi;
-      
-      // Bit-fields require special handling, they do not force the
-      // structure to be passed in memory even if unaligned, and
-      // therefore they can straddle an eightbyte.
-      if (BitField) {
-        // Ignore padding bit-fields.
-        if (i->isUnnamedBitfield())
-          continue;
-
-        uint64_t Offset = OffsetBase + Layout.getFieldOffset(idx);
-        uint64_t Size = i->getBitWidth()->EvaluateAsInt(Context).getZExtValue();
-
-        uint64_t EB_Lo = Offset / 64;
-        uint64_t EB_Hi = (Offset + Size - 1) / 64;
-        FieldLo = FieldHi = NoClass;
-        if (EB_Lo) {
-          assert(EB_Hi == EB_Lo && "Invalid classification, type > 16 bytes.");
-          FieldLo = NoClass;
-          FieldHi = Integer;
-        } else { 
-          FieldLo = Integer;
-          FieldHi = EB_Hi ? Integer : NoClass;
-        }
-      } else
-        classify(i->getType(), Context, Offset, FieldLo, FieldHi);
-      Lo = merge(Lo, FieldLo);
-      Hi = merge(Hi, FieldHi);
-      if (Lo == Memory || Hi == Memory)
-        break;
-    }
-
-    // AMD64-ABI 3.2.3p2: Rule 5. Then a post merger cleanup is done:
-    //
-    // (a) If one of the classes is MEMORY, the whole argument is
-    // passed in memory.
-    //
-    // (b) If SSEUP is not preceeded by SSE, it is converted to SSE.
-
-    // The first of these conditions is guaranteed by how we implement
-    // the merge (just bail). 
-    //
-    // The second condition occurs in the case of unions; for example
-    // union { _Complex double; unsigned; }.
-    if (Hi == Memory)
-      Lo = Memory;
-    if (Hi == SSEUp && Lo != SSE)
-      Hi = SSE;
-  }
-}
-
-ABIArgInfo X86_64ABIInfo::getCoerceResult(QualType Ty,
-                                          const llvm::Type *CoerceTo,
-                                          ASTContext &Context) const {
-  if (CoerceTo == llvm::Type::Int64Ty) {
-    // Integer and pointer types will end up in a general purpose
-    // register.
-    if (Ty->isIntegralType() || Ty->isPointerType())
-      return ABIArgInfo::getDirect();
-
-  } else if (CoerceTo == llvm::Type::DoubleTy) {
-    // FIXME: It would probably be better to make CGFunctionInfo only map using
-    // canonical types than to canonize here.
-    QualType CTy = Context.getCanonicalType(Ty);
-  
-    // Float and double end up in a single SSE reg.
-    if (CTy == Context.FloatTy || CTy == Context.DoubleTy)
-      return ABIArgInfo::getDirect();
-
-  }
-
-  return ABIArgInfo::getCoerce(CoerceTo);
-}
-
-ABIArgInfo X86_64ABIInfo::getIndirectResult(QualType Ty,
-                                            ASTContext &Context) const {
-  // If this is a scalar LLVM value then assume LLVM will pass it in the right
-  // place naturally.
-  if (!CodeGenFunction::hasAggregateLLVMType(Ty))
-    return ABIArgInfo::getDirect();
-
-  // FIXME: Set alignment correctly.
-  return ABIArgInfo::getIndirect(0);
-}
-
-ABIArgInfo X86_64ABIInfo::classifyReturnType(QualType RetTy,
-                                            ASTContext &Context) const {
-  // AMD64-ABI 3.2.3p4: Rule 1. Classify the return type with the
-  // classification algorithm.
-  X86_64ABIInfo::Class Lo, Hi;
-  classify(RetTy, Context, 0, Lo, Hi);
-
-  // Check some invariants.
-  assert((Hi != Memory || Lo == Memory) && "Invalid memory classification.");
-  assert((Lo != NoClass || Hi == NoClass) && "Invalid null classification.");
-  assert((Hi != SSEUp || Lo == SSE) && "Invalid SSEUp classification.");
-
-  const llvm::Type *ResType = 0;
-  switch (Lo) {
-  case NoClass:
-    return ABIArgInfo::getIgnore();
-
-  case SSEUp:
-  case X87Up:
-    assert(0 && "Invalid classification for lo word.");
-
-    // AMD64-ABI 3.2.3p4: Rule 2. Types of class memory are returned via
-    // hidden argument.
-  case Memory:
-    return getIndirectResult(RetTy, Context);
-
-    // AMD64-ABI 3.2.3p4: Rule 3. If the class is INTEGER, the next
-    // available register of the sequence %rax, %rdx is used.
-  case Integer:
-    ResType = llvm::Type::Int64Ty; break;
-
-    // AMD64-ABI 3.2.3p4: Rule 4. If the class is SSE, the next
-    // available SSE register of the sequence %xmm0, %xmm1 is used.
-  case SSE:
-    ResType = llvm::Type::DoubleTy; break;
-
-    // AMD64-ABI 3.2.3p4: Rule 6. If the class is X87, the value is
-    // returned on the X87 stack in %st0 as 80-bit x87 number.
-  case X87:
-    ResType = llvm::Type::X86_FP80Ty; break;
-
-    // AMD64-ABI 3.2.3p4: Rule 8. If the class is COMPLEX_X87, the real
-    // part of the value is returned in %st0 and the imaginary part in
-    // %st1.
-  case ComplexX87:
-    assert(Hi == ComplexX87 && "Unexpected ComplexX87 classification.");
-    ResType = llvm::StructType::get(llvm::Type::X86_FP80Ty,
-                                    llvm::Type::X86_FP80Ty,
-                                    NULL);
-    break;    
-  }
-
-  switch (Hi) {
-    // Memory was handled previously and X87 should
-    // never occur as a hi class.
-  case Memory:
-  case X87:
-    assert(0 && "Invalid classification for hi word.");
-
-  case ComplexX87: // Previously handled.
-  case NoClass: break;
-
-  case Integer:
-    ResType = llvm::StructType::get(ResType, llvm::Type::Int64Ty, NULL);
-    break;
-  case SSE:    
-    ResType = llvm::StructType::get(ResType, llvm::Type::DoubleTy, NULL);
-    break;
-
-    // AMD64-ABI 3.2.3p4: Rule 5. If the class is SSEUP, the eightbyte
-    // is passed in the upper half of the last used SSE register.
-    //
-    // SSEUP should always be preceeded by SSE, just widen.
-  case SSEUp:
-    assert(Lo == SSE && "Unexpected SSEUp classification.");
-    ResType = llvm::VectorType::get(llvm::Type::DoubleTy, 2);
-    break;
-
-    // AMD64-ABI 3.2.3p4: Rule 7. If the class is X87UP, the value is
-    // returned together with the previous X87 value in %st0.
-  case X87Up:
-    // If X87Up is preceeded by X87, we don't need to do
-    // anything. However, in some cases with unions it may not be
-    // preceeded by X87. In such situations we follow gcc and pass the
-    // extra bits in an SSE reg.
-    if (Lo != X87) 
-      ResType = llvm::StructType::get(ResType, llvm::Type::DoubleTy, NULL);
-    break;
-  }
-
-  return getCoerceResult(RetTy, ResType, Context);
-}
-
-ABIArgInfo X86_64ABIInfo::classifyArgumentType(QualType Ty, ASTContext &Context,
-                                               unsigned &neededInt,
-                                               unsigned &neededSSE) const {
-  X86_64ABIInfo::Class Lo, Hi;
-  classify(Ty, Context, 0, Lo, Hi);
-  
-  // Check some invariants.
-  // FIXME: Enforce these by construction.
-  assert((Hi != Memory || Lo == Memory) && "Invalid memory classification.");