xref: /external/clang/lib/CodeGen/CGBuiltin.cpp

//===---- CGBuiltin.cpp - Emit LLVM Code for builtins ---------------------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This contains code to emit Builtin calls as LLVM code.
//
//===----------------------------------------------------------------------===//

#include "TargetInfo.h"
#include "CodeGenFunction.h"
#include "CodeGenModule.h"
#include "CGObjCRuntime.h"
#include "clang/Basic/TargetInfo.h"
#include "clang/AST/APValue.h"
#include "clang/AST/ASTContext.h"
#include "clang/AST/Decl.h"
#include "clang/Basic/TargetBuiltins.h"
#include "llvm/Intrinsics.h"
#include "llvm/Target/TargetData.h"
using namespace clang;
using namespace CodeGen;
using namespace llvm;

static void EmitMemoryBarrier(CodeGenFunction &CGF,
                              bool LoadLoad, bool LoadStore,
                              bool StoreLoad, bool StoreStore,
                              bool Device) {
  Value *True = llvm::ConstantInt::getTrue(CGF.getLLVMContext());
  Value *False = llvm::ConstantInt::getFalse(CGF.getLLVMContext());
  Value *C[5] = { LoadLoad ? True : False,
                  LoadStore ? True : False,
                  StoreLoad ? True : False,
                  StoreStore ? True : False,
                  Device ? True : False };
  CGF.Builder.CreateCall(CGF.CGM.getIntrinsic(Intrinsic::memory_barrier),
                         C, C + 5);
}

/// Emit the conversions required to turn the given value into an
/// integer of the given size.
static Value *EmitToInt(CodeGenFunction &CGF, llvm::Value *V,
                        QualType T, const llvm::IntegerType *IntType) {
  V = CGF.EmitToMemory(V, T);

  if (V->getType()->isPointerTy())
    return CGF.Builder.CreatePtrToInt(V, IntType);

  assert(V->getType() == IntType);
  return V;
}

static Value *EmitFromInt(CodeGenFunction &CGF, llvm::Value *V,
                          QualType T, const llvm::Type *ResultType) {
  V = CGF.EmitFromMemory(V, T);

  if (ResultType->isPointerTy())
    return CGF.Builder.CreateIntToPtr(V, ResultType);

  assert(V->getType() == ResultType);
  return V;
}

// The atomic builtins are also full memory barriers. This is a utility for
// wrapping a call to the builtins with memory barriers.
static Value *EmitCallWithBarrier(CodeGenFunction &CGF, Value *Fn,
                                  Value **ArgBegin, Value **ArgEnd) {
  // FIXME: We need a target hook for whether this applies to device memory or
  // not.
  bool Device = true;

  // Create barriers both before and after the call.
  EmitMemoryBarrier(CGF, true, true, true, true, Device);
  Value *Result = CGF.Builder.CreateCall(Fn, ArgBegin, ArgEnd);
  EmitMemoryBarrier(CGF, true, true, true, true, Device);
  return Result;
}

/// Utility to insert an atomic instruction based on Instrinsic::ID
/// and the expression node.
static RValue EmitBinaryAtomic(CodeGenFunction &CGF,
                               Intrinsic::ID Id, const CallExpr *E) {
  QualType T = E->getType();
  assert(E->getArg(0)->getType()->isPointerType());
  assert(CGF.getContext().hasSameUnqualifiedType(T,
                                  E->getArg(0)->getType()->getPointeeType()));
  assert(CGF.getContext().hasSameUnqualifiedType(T, E->getArg(1)->getType()));

  llvm::Value *DestPtr = CGF.EmitScalarExpr(E->getArg(0));
  unsigned AddrSpace =
    cast<llvm::PointerType>(DestPtr->getType())->getAddressSpace();

  const llvm::IntegerType *IntType =
    llvm::IntegerType::get(CGF.getLLVMContext(),
                           CGF.getContext().getTypeSize(T));
  const llvm::Type *IntPtrType = IntType->getPointerTo(AddrSpace);

  const llvm::Type *IntrinsicTypes[2] = { IntType, IntPtrType };
  llvm::Value *AtomF = CGF.CGM.getIntrinsic(Id, IntrinsicTypes, 2);

  llvm::Value *Args[2];
  Args[0] = CGF.Builder.CreateBitCast(DestPtr, IntPtrType);
  Args[1] = CGF.EmitScalarExpr(E->getArg(1));
  const llvm::Type *ValueType = Args[1]->getType();
  Args[1] = EmitToInt(CGF, Args[1], T, IntType);

  llvm::Value *Result = EmitCallWithBarrier(CGF, AtomF, Args, Args + 2);
  Result = EmitFromInt(CGF, Result, T, ValueType);
  return RValue::get(Result);
}

/// Utility to insert an atomic instruction based Instrinsic::ID and
/// the expression node, where the return value is the result of the
/// operation.
static RValue EmitBinaryAtomicPost(CodeGenFunction &CGF,
                                   Intrinsic::ID Id, const CallExpr *E,
                                   Instruction::BinaryOps Op) {
  QualType T = E->getType();
  assert(E->getArg(0)->getType()->isPointerType());
  assert(CGF.getContext().hasSameUnqualifiedType(T,
                                  E->getArg(0)->getType()->getPointeeType()));
  assert(CGF.getContext().hasSameUnqualifiedType(T, E->getArg(1)->getType()));

  llvm::Value *DestPtr = CGF.EmitScalarExpr(E->getArg(0));
  unsigned AddrSpace =
    cast<llvm::PointerType>(DestPtr->getType())->getAddressSpace();

  const llvm::IntegerType *IntType =
    llvm::IntegerType::get(CGF.getLLVMContext(),
                           CGF.getContext().getTypeSize(T));
  const llvm::Type *IntPtrType = IntType->getPointerTo(AddrSpace);

  const llvm::Type *IntrinsicTypes[2] = { IntType, IntPtrType };
  llvm::Value *AtomF = CGF.CGM.getIntrinsic(Id, IntrinsicTypes, 2);

  llvm::Value *Args[2];
  Args[1] = CGF.EmitScalarExpr(E->getArg(1));
  const llvm::Type *ValueType = Args[1]->getType();
  Args[1] = EmitToInt(CGF, Args[1], T, IntType);
  Args[0] = CGF.Builder.CreateBitCast(DestPtr, IntPtrType);

  llvm::Value *Result = EmitCallWithBarrier(CGF, AtomF, Args, Args + 2);
  Result = CGF.Builder.CreateBinOp(Op, Result, Args[1]);
  Result = EmitFromInt(CGF, Result, T, ValueType);
  return RValue::get(Result);
}

/// EmitFAbs - Emit a call to fabs/fabsf/fabsl, depending on the type of ValTy,
/// which must be a scalar floating point type.
static Value *EmitFAbs(CodeGenFunction &CGF, Value *V, QualType ValTy) {
  const BuiltinType *ValTyP = ValTy->getAs<BuiltinType>();
  assert(ValTyP && "isn't scalar fp type!");

  StringRef FnName;
  switch (ValTyP->getKind()) {
  default: assert(0 && "Isn't a scalar fp type!");
  case BuiltinType::Float:      FnName = "fabsf"; break;
  case BuiltinType::Double:     FnName = "fabs"; break;
  case BuiltinType::LongDouble: FnName = "fabsl"; break;
  }

  // The prototype is something that takes and returns whatever V's type is.
  std::vector<const llvm::Type*> Args;
  Args.push_back(V->getType());
  llvm::FunctionType *FT = llvm::FunctionType::get(V->getType(), Args, false);
  llvm::Value *Fn = CGF.CGM.CreateRuntimeFunction(FT, FnName);

  return CGF.Builder.CreateCall(Fn, V, "abs");
}

RValue CodeGenFunction::EmitBuiltinExpr(const FunctionDecl *FD,
                                        unsigned BuiltinID, const CallExpr *E) {
  // See if we can constant fold this builtin.  If so, don't emit it at all.
  Expr::EvalResult Result;
  if (E->Evaluate(Result, CGM.getContext())) {
    if (Result.Val.isInt())
      return RValue::get(llvm::ConstantInt::get(VMContext,
                                                Result.Val.getInt()));
    if (Result.Val.isFloat())
      return RValue::get(ConstantFP::get(VMContext, Result.Val.getFloat()));
  }

  switch (BuiltinID) {
  default: break;  // Handle intrinsics and libm functions below.
  case Builtin::BI__builtin___CFStringMakeConstantString:
  case Builtin::BI__builtin___NSStringMakeConstantString:
    return RValue::get(CGM.EmitConstantExpr(E, E->getType(), 0));
  case Builtin::BI__builtin_stdarg_start:
  case Builtin::BI__builtin_va_start:
  case Builtin::BI__builtin_va_end: {
    Value *ArgValue = EmitVAListRef(E->getArg(0));
    const llvm::Type *DestType = llvm::Type::getInt8PtrTy(VMContext);
    if (ArgValue->getType() != DestType)
      ArgValue = Builder.CreateBitCast(ArgValue, DestType,
                                       ArgValue->getName().data());

    Intrinsic::ID inst = (BuiltinID == Builtin::BI__builtin_va_end) ?
      Intrinsic::vaend : Intrinsic::vastart;
    return RValue::get(Builder.CreateCall(CGM.getIntrinsic(inst), ArgValue));
  }
  case Builtin::BI__builtin_va_copy: {
    Value *DstPtr = EmitVAListRef(E->getArg(0));
    Value *SrcPtr = EmitVAListRef(E->getArg(1));

    const llvm::Type *Type = llvm::Type::getInt8PtrTy(VMContext);

    DstPtr = Builder.CreateBitCast(DstPtr, Type);
    SrcPtr = Builder.CreateBitCast(SrcPtr, Type);
    return RValue::get(Builder.CreateCall2(CGM.getIntrinsic(Intrinsic::vacopy),
                                           DstPtr, SrcPtr));
  }
  case Builtin::BI__builtin_abs: {
    Value *ArgValue = EmitScalarExpr(E->getArg(0));

    Value *NegOp = Builder.CreateNeg(ArgValue, "neg");
    Value *CmpResult =
    Builder.CreateICmpSGE(ArgValue,
                          llvm::Constant::getNullValue(ArgValue->getType()),
                                                            "abscond");
    Value *Result =
      Builder.CreateSelect(CmpResult, ArgValue, NegOp, "abs");

    return RValue::get(Result);
  }
  case Builtin::BI__builtin_ctz:
  case Builtin::BI__builtin_ctzl:
  case Builtin::BI__builtin_ctzll: {
    Value *ArgValue = EmitScalarExpr(E->getArg(0));

    const llvm::Type *ArgType = ArgValue->getType();
    Value *F = CGM.getIntrinsic(Intrinsic::cttz, &ArgType, 1);

    const llvm::Type *ResultType = ConvertType(E->getType());
    Value *Result = Builder.CreateCall(F, ArgValue, "tmp");
    if (Result->getType() != ResultType)
      Result = Builder.CreateIntCast(Result, ResultType, /*isSigned*/true,
                                     "cast");
    return RValue::get(Result);
  }
  case Builtin::BI__builtin_clz:
  case Builtin::BI__builtin_clzl:
  case Builtin::BI__builtin_clzll: {
    Value *ArgValue = EmitScalarExpr(E->getArg(0));

    const llvm::Type *ArgType = ArgValue->getType();
    Value *F = CGM.getIntrinsic(Intrinsic::ctlz, &ArgType, 1);

    const llvm::Type *ResultType = ConvertType(E->getType());
    Value *Result = Builder.CreateCall(F, ArgValue, "tmp");
    if (Result->getType() != ResultType)
      Result = Builder.CreateIntCast(Result, ResultType, /*isSigned*/true,
                                     "cast");
    return RValue::get(Result);
  }
  case Builtin::BI__builtin_ffs:
  case Builtin::BI__builtin_ffsl:
  case Builtin::BI__builtin_ffsll: {
    // ffs(x) -> x ? cttz(x) + 1 : 0
    Value *ArgValue = EmitScalarExpr(E->getArg(0));

    const llvm::Type *ArgType = ArgValue->getType();
    Value *F = CGM.getIntrinsic(Intrinsic::cttz, &ArgType, 1);

    const llvm::Type *ResultType = ConvertType(E->getType());
    Value *Tmp = Builder.CreateAdd(Builder.CreateCall(F, ArgValue, "tmp"),
                                   llvm::ConstantInt::get(ArgType, 1), "tmp");
    Value *Zero = llvm::Constant::getNullValue(ArgType);
    Value *IsZero = Builder.CreateICmpEQ(ArgValue, Zero, "iszero");
    Value *Result = Builder.CreateSelect(IsZero, Zero, Tmp, "ffs");
    if (Result->getType() != ResultType)
      Result = Builder.CreateIntCast(Result, ResultType, /*isSigned*/true,
                                     "cast");
    return RValue::get(Result);
  }
  case Builtin::BI__builtin_parity:
  case Builtin::BI__builtin_parityl:
  case Builtin::BI__builtin_parityll: {
    // parity(x) -> ctpop(x) & 1
    Value *ArgValue = EmitScalarExpr(E->getArg(0));

    const llvm::Type *ArgType = ArgValue->getType();
    Value *F = CGM.getIntrinsic(Intrinsic::ctpop, &ArgType, 1);

    const llvm::Type *ResultType = ConvertType(E->getType());
    Value *Tmp = Builder.CreateCall(F, ArgValue, "tmp");
    Value *Result = Builder.CreateAnd(Tmp, llvm::ConstantInt::get(ArgType, 1),
                                      "tmp");
    if (Result->getType() != ResultType)
      Result = Builder.CreateIntCast(Result, ResultType, /*isSigned*/true,
                                     "cast");
    return RValue::get(Result);
  }
  case Builtin::BI__builtin_popcount:
  case Builtin::BI__builtin_popcountl:
  case Builtin::BI__builtin_popcountll: {
    Value *ArgValue = EmitScalarExpr(E->getArg(0));

    const llvm::Type *ArgType = ArgValue->getType();
    Value *F = CGM.getIntrinsic(Intrinsic::ctpop, &ArgType, 1);

    const llvm::Type *ResultType = ConvertType(E->getType());
    Value *Result = Builder.CreateCall(F, ArgValue, "tmp");
    if (Result->getType() != ResultType)
      Result = Builder.CreateIntCast(Result, ResultType, /*isSigned*/true,
                                     "cast");
    return RValue::get(Result);
  }
  case Builtin::BI__builtin_expect: {
    // FIXME: pass expect through to LLVM
    if (E->getArg(1)->HasSideEffects(getContext()))
      (void)EmitScalarExpr(E->getArg(1));
    return RValue::get(EmitScalarExpr(E->getArg(0)));
  }
  case Builtin::BI__builtin_bswap32:
  case Builtin::BI__builtin_bswap64: {
    Value *ArgValue = EmitScalarExpr(E->getArg(0));
    const llvm::Type *ArgType = ArgValue->getType();
    Value *F = CGM.getIntrinsic(Intrinsic::bswap, &ArgType, 1);
    return RValue::get(Builder.CreateCall(F, ArgValue, "tmp"));
  }
  case Builtin::BI__builtin_object_size: {
    // We pass this builtin onto the optimizer so that it can
    // figure out the object size in more complex cases.
    const llvm::Type *ResType[] = {
      ConvertType(E->getType())
    };

    // LLVM only supports 0 and 2, make sure that we pass along that
    // as a boolean.
    Value *Ty = EmitScalarExpr(E->getArg(1));
    ConstantInt *CI = dyn_cast<ConstantInt>(Ty);
    assert(CI);
    uint64_t val = CI->getZExtValue();
    CI = ConstantInt::get(llvm::Type::getInt1Ty(VMContext), (val & 0x2) >> 1);

    Value *F = CGM.getIntrinsic(Intrinsic::objectsize, ResType, 1);
    return RValue::get(Builder.CreateCall2(F,
                                           EmitScalarExpr(E->getArg(0)),
                                           CI));
  }
  case Builtin::BI__builtin_prefetch: {
    Value *Locality, *RW, *Address = EmitScalarExpr(E->getArg(0));
    // FIXME: Technically these constants should of type 'int', yes?
    RW = (E->getNumArgs() > 1) ? EmitScalarExpr(E->getArg(1)) :
      llvm::ConstantInt::get(Int32Ty, 0);
    Locality = (E->getNumArgs() > 2) ? EmitScalarExpr(E->getArg(2)) :
      llvm::ConstantInt::get(Int32Ty, 3);
    Value *F = CGM.getIntrinsic(Intrinsic::prefetch, 0, 0);
    return RValue::get(Builder.CreateCall3(F, Address, RW, Locality));
  }
  case Builtin::BI__builtin_trap: {
    Value *F = CGM.getIntrinsic(Intrinsic::trap, 0, 0);
    return RValue::get(Builder.CreateCall(F));
  }
  case Builtin::BI__builtin_unreachable: {
    if (CatchUndefined && HaveInsertPoint())
      EmitBranch(getTrapBB());
    Value *V = Builder.CreateUnreachable();
    Builder.ClearInsertionPoint();
    return RValue::get(V);
  }

  case Builtin::BI__builtin_powi:
  case Builtin::BI__builtin_powif:
  case Builtin::BI__builtin_powil: {
    Value *Base = EmitScalarExpr(E->getArg(0));
    Value *Exponent = EmitScalarExpr(E->getArg(1));
    const llvm::Type *ArgType = Base->getType();
    Value *F = CGM.getIntrinsic(Intrinsic::powi, &ArgType, 1);
    return RValue::get(Builder.CreateCall2(F, Base, Exponent, "tmp"));
  }

  case Builtin::BI__builtin_isgreater:
  case Builtin::BI__builtin_isgreaterequal:
  case Builtin::BI__builtin_isless:
  case Builtin::BI__builtin_islessequal:
  case Builtin::BI__builtin_islessgreater:
  case Builtin::BI__builtin_isunordered: {
    // Ordered comparisons: we know the arguments to these are matching scalar
    // floating point values.
    Value *LHS = EmitScalarExpr(E->getArg(0));
    Value *RHS = EmitScalarExpr(E->getArg(1));

    switch (BuiltinID) {
    default: assert(0 && "Unknown ordered comparison");
    case Builtin::BI__builtin_isgreater:
      LHS = Builder.CreateFCmpOGT(LHS, RHS, "cmp");
      break;
    case Builtin::BI__builtin_isgreaterequal:
      LHS = Builder.CreateFCmpOGE(LHS, RHS, "cmp");
      break;
    case Builtin::BI__builtin_isless:
      LHS = Builder.CreateFCmpOLT(LHS, RHS, "cmp");
      break;
    case Builtin::BI__builtin_islessequal:
      LHS = Builder.CreateFCmpOLE(LHS, RHS, "cmp");
      break;
    case Builtin::BI__builtin_islessgreater:
      LHS = Builder.CreateFCmpONE(LHS, RHS, "cmp");
      break;
    case Builtin::BI__builtin_isunordered:
      LHS = Builder.CreateFCmpUNO(LHS, RHS, "cmp");
      break;
    }
    // ZExt bool to int type.
    return RValue::get(Builder.CreateZExt(LHS, ConvertType(E->getType()),
                                          "tmp"));
  }
  case Builtin::BI__builtin_isnan: {
    Value *V = EmitScalarExpr(E->getArg(0));
    V = Builder.CreateFCmpUNO(V, V, "cmp");
    return RValue::get(Builder.CreateZExt(V, ConvertType(E->getType()), "tmp"));
  }

  case Builtin::BI__builtin_isinf: {
    // isinf(x) --> fabs(x) == infinity
    Value *V = EmitScalarExpr(E->getArg(0));
    V = EmitFAbs(*this, V, E->getArg(0)->getType());

    V = Builder.CreateFCmpOEQ(V, ConstantFP::getInfinity(V->getType()),"isinf");
    return RValue::get(Builder.CreateZExt(V, ConvertType(E->getType()), "tmp"));
  }

  // TODO: BI__builtin_isinf_sign
  //   isinf_sign(x) -> isinf(x) ? (signbit(x) ? -1 : 1) : 0

  case Builtin::BI__builtin_isnormal: {
    // isnormal(x) --> x == x && fabsf(x) < infinity && fabsf(x) >= float_min
    Value *V = EmitScalarExpr(E->getArg(0));
    Value *Eq = Builder.CreateFCmpOEQ(V, V, "iseq");

    Value *Abs = EmitFAbs(*this, V, E->getArg(0)->getType());
    Value *IsLessThanInf =
      Builder.CreateFCmpULT(Abs, ConstantFP::getInfinity(V->getType()),"isinf");
    APFloat Smallest = APFloat::getSmallestNormalized(
                   getContext().getFloatTypeSemantics(E->getArg(0)->getType()));
    Value *IsNormal =
      Builder.CreateFCmpUGE(Abs, ConstantFP::get(V->getContext(), Smallest),
                            "isnormal");
    V = Builder.CreateAnd(Eq, IsLessThanInf, "and");
    V = Builder.CreateAnd(V, IsNormal, "and");
    return RValue::get(Builder.CreateZExt(V, ConvertType(E->getType())));
  }

  case Builtin::BI__builtin_isfinite: {
    // isfinite(x) --> x == x && fabs(x) != infinity; }
    Value *V = EmitScalarExpr(E->getArg(0));
    Value *Eq = Builder.CreateFCmpOEQ(V, V, "iseq");

    Value *Abs = EmitFAbs(*this, V, E->getArg(0)->getType());
    Value *IsNotInf =
      Builder.CreateFCmpUNE(Abs, ConstantFP::getInfinity(V->getType()),"isinf");

    V = Builder.CreateAnd(Eq, IsNotInf, "and");
    return RValue::get(Builder.CreateZExt(V, ConvertType(E->getType())));
  }

  case Builtin::BI__builtin_fpclassify: {
    Value *V = EmitScalarExpr(E->getArg(5));
    const llvm::Type *Ty = ConvertType(E->getArg(5)->getType());

    // Create Result
    BasicBlock *Begin = Builder.GetInsertBlock();
    BasicBlock *End = createBasicBlock("fpclassify_end", this->CurFn);
    Builder.SetInsertPoint(End);
    PHINode *Result =
      Builder.CreatePHI(ConvertType(E->getArg(0)->getType()),
                        "fpclassify_result");

    // if (V==0) return FP_ZERO
    Builder.SetInsertPoint(Begin);
    Value *IsZero = Builder.CreateFCmpOEQ(V, Constant::getNullValue(Ty),
                                          "iszero");
    Value *ZeroLiteral = EmitScalarExpr(E->getArg(4));
    BasicBlock *NotZero = createBasicBlock("fpclassify_not_zero", this->CurFn);
    Builder.CreateCondBr(IsZero, End, NotZero);
    Result->addIncoming(ZeroLiteral, Begin);

    // if (V != V) return FP_NAN
    Builder.SetInsertPoint(NotZero);
    Value *IsNan = Builder.CreateFCmpUNO(V, V, "cmp");
    Value *NanLiteral = EmitScalarExpr(E->getArg(0));
    BasicBlock *NotNan = createBasicBlock("fpclassify_not_nan", this->CurFn);
    Builder.CreateCondBr(IsNan, End, NotNan);
    Result->addIncoming(NanLiteral, NotZero);

    // if (fabs(V) == infinity) return FP_INFINITY
    Builder.SetInsertPoint(NotNan);
    Value *VAbs = EmitFAbs(*this, V, E->getArg(5)->getType());
    Value *IsInf =
      Builder.CreateFCmpOEQ(VAbs, ConstantFP::getInfinity(V->getType()),
                            "isinf");
    Value *InfLiteral = EmitScalarExpr(E->getArg(1));
    BasicBlock *NotInf = createBasicBlock("fpclassify_not_inf", this->CurFn);
    Builder.CreateCondBr(IsInf, End, NotInf);
    Result->addIncoming(InfLiteral, NotNan);

    // if (fabs(V) >= MIN_NORMAL) return FP_NORMAL else FP_SUBNORMAL
    Builder.SetInsertPoint(NotInf);
    APFloat Smallest = APFloat::getSmallestNormalized(
        getContext().getFloatTypeSemantics(E->getArg(5)->getType()));
    Value *IsNormal =
      Builder.CreateFCmpUGE(VAbs, ConstantFP::get(V->getContext(), Smallest),
                            "isnormal");
    Value *NormalResult =
      Builder.CreateSelect(IsNormal, EmitScalarExpr(E->getArg(2)),
                           EmitScalarExpr(E->getArg(3)));
    Builder.CreateBr(End);
    Result->addIncoming(NormalResult, NotInf);

    // return Result
    Builder.SetInsertPoint(End);
    return RValue::get(Result);
  }

  case Builtin::BIalloca:
  case Builtin::BI__builtin_alloca: {
    Value *Size = EmitScalarExpr(E->getArg(0));
    return RValue::get(Builder.CreateAlloca(llvm::Type::getInt8Ty(VMContext), Size, "tmp"));
  }
  case Builtin::BIbzero:
  case Builtin::BI__builtin_bzero: {
    Value *Address = EmitScalarExpr(E->getArg(0));
    Value *SizeVal = EmitScalarExpr(E->getArg(1));
    Builder.CreateMemSet(Address, Builder.getInt8(0), SizeVal, 1, false);
    return RValue::get(Address);
  }
  case Builtin::BImemcpy:
  case Builtin::BI__builtin_memcpy: {
    Value *Address = EmitScalarExpr(E->getArg(0));
    Value *SrcAddr = EmitScalarExpr(E->getArg(1));
    Value *SizeVal = EmitScalarExpr(E->getArg(2));
    Builder.CreateMemCpy(Address, SrcAddr, SizeVal, 1, false);
    return RValue::get(Address);
  }

  case Builtin::BI__builtin_objc_memmove_collectable: {
    Value *Address = EmitScalarExpr(E->getArg(0));
    Value *SrcAddr = EmitScalarExpr(E->getArg(1));
    Value *SizeVal = EmitScalarExpr(E->getArg(2));
    CGM.getObjCRuntime().EmitGCMemmoveCollectable(*this,
                                                  Address, SrcAddr, SizeVal);
    return RValue::get(Address);
  }

  case Builtin::BImemmove:
  case Builtin::BI__builtin_memmove: {
    Value *Address = EmitScalarExpr(E->getArg(0));
    Value *SrcAddr = EmitScalarExpr(E->getArg(1));
    Value *SizeVal = EmitScalarExpr(E->getArg(2));
    Builder.CreateMemMove(Address, SrcAddr, SizeVal, 1, false);
    return RValue::get(Address);
  }
  case Builtin::BImemset:
  case Builtin::BI__builtin_memset: {
    Value *Address = EmitScalarExpr(E->getArg(0));
    Value *ByteVal = Builder.CreateTrunc(EmitScalarExpr(E->getArg(1)),
                                         Builder.getInt8Ty());
    Value *SizeVal = EmitScalarExpr(E->getArg(2));
    Builder.CreateMemSet(Address, ByteVal, SizeVal, 1, false);
    return RValue::get(Address);
  }
  case Builtin::BI__builtin_dwarf_cfa: {
    // The offset in bytes from the first argument to the CFA.
    //
    // Why on earth is this in the frontend?  Is there any reason at
    // all that the backend can't reasonably determine this while
    // lowering llvm.eh.dwarf.cfa()?
    //
    // TODO: If there's a satisfactory reason, add a target hook for
    // this instead of hard-coding 0, which is correct for most targets.
    int32_t Offset = 0;

    Value *F = CGM.getIntrinsic(Intrinsic::eh_dwarf_cfa, 0, 0);
    return RValue::get(Builder.CreateCall(F,
                                      llvm::ConstantInt::get(Int32Ty, Offset)));
  }
  case Builtin::BI__builtin_return_address: {
    Value *Depth = EmitScalarExpr(E->getArg(0));
    Depth = Builder.CreateIntCast(Depth, Int32Ty, false, "tmp");
    Value *F = CGM.getIntrinsic(Intrinsic::returnaddress, 0, 0);
    return RValue::get(Builder.CreateCall(F, Depth));
  }
  case Builtin::BI__builtin_frame_address: {
    Value *Depth = EmitScalarExpr(E->getArg(0));
    Depth = Builder.CreateIntCast(Depth, Int32Ty, false, "tmp");
    Value *F = CGM.getIntrinsic(Intrinsic::frameaddress, 0, 0);
    return RValue::get(Builder.CreateCall(F, Depth));
  }
  case Builtin::BI__builtin_extract_return_addr: {
    Value *Address = EmitScalarExpr(E->getArg(0));
    Value *Result = getTargetHooks().decodeReturnAddress(*this, Address);
    return RValue::get(Result);
  }
  case Builtin::BI__builtin_frob_return_addr: {
    Value *Address = EmitScalarExpr(E->getArg(0));
    Value *Result = getTargetHooks().encodeReturnAddress(*this, Address);
    return RValue::get(Result);
  }
  case Builtin::BI__builtin_dwarf_sp_column: {
    const llvm::IntegerType *Ty
      = cast<llvm::IntegerType>(ConvertType(E->getType()));
    int Column = getTargetHooks().getDwarfEHStackPointer(CGM);
    if (Column == -1) {
      CGM.ErrorUnsupported(E, "__builtin_dwarf_sp_column");
      return RValue::get(llvm::UndefValue::get(Ty));
    }
    return RValue::get(llvm::ConstantInt::get(Ty, Column, true));
  }
  case Builtin::BI__builtin_init_dwarf_reg_size_table: {
    Value *Address = EmitScalarExpr(E->getArg(0));
    if (getTargetHooks().initDwarfEHRegSizeTable(*this, Address))
      CGM.ErrorUnsupported(E, "__builtin_init_dwarf_reg_size_table");
    return RValue::get(llvm::UndefValue::get(ConvertType(E->getType())));
  }
  case Builtin::BI__builtin_eh_return: {
    Value *Int = EmitScalarExpr(E->getArg(0));
    Value *Ptr = EmitScalarExpr(E->getArg(1));

    const llvm::IntegerType *IntTy = cast<llvm::IntegerType>(Int->getType());
    assert((IntTy->getBitWidth() == 32 || IntTy->getBitWidth() == 64) &&
           "LLVM's __builtin_eh_return only supports 32- and 64-bit variants");
    Value *F = CGM.getIntrinsic(IntTy->getBitWidth() == 32
                                  ? Intrinsic::eh_return_i32
                                  : Intrinsic::eh_return_i64,
                                0, 0);
    Builder.CreateCall2(F, Int, Ptr);
    Value *V = Builder.CreateUnreachable();
    Builder.ClearInsertionPoint();
    return RValue::get(V);
  }
  case Builtin::BI__builtin_unwind_init: {
    Value *F = CGM.getIntrinsic(Intrinsic::eh_unwind_init, 0, 0);
    return RValue::get(Builder.CreateCall(F));
  }
  case Builtin::BI__builtin_extend_pointer: {
    // Extends a pointer to the size of an _Unwind_Word, which is
    // uint64_t on all platforms.  Generally this gets poked into a
    // register and eventually used as an address, so if the
    // addressing registers are wider than pointers and the platform
    // doesn't implicitly ignore high-order bits when doing
    // addressing, we need to make sure we zext / sext based on
    // the platform's expectations.
    //
    // See: http://gcc.gnu.org/ml/gcc-bugs/2002-02/msg00237.html

    LLVMContext &C = CGM.getLLVMContext();

    // Cast the pointer to intptr_t.
    Value *Ptr = EmitScalarExpr(E->getArg(0));
    const llvm::IntegerType *IntPtrTy = CGM.getTargetData().getIntPtrType(C);
    Value *Result = Builder.CreatePtrToInt(Ptr, IntPtrTy, "extend.cast");

    // If that's 64 bits, we're done.
    if (IntPtrTy->getBitWidth() == 64)
      return RValue::get(Result);

    // Otherwise, ask the codegen data what to do.
    if (getTargetHooks().extendPointerWithSExt())
      return RValue::get(Builder.CreateSExt(Result, Int64Ty, "extend.sext"));
    else
      return RValue::get(Builder.CreateZExt(Result, Int64Ty, "extend.zext"));
  }
  case Builtin::BI__builtin_setjmp: {
    // Buffer is a void**.
    Value *Buf = EmitScalarExpr(E->getArg(0));

    // Store the frame pointer to the setjmp buffer.
    Value *FrameAddr =
      Builder.CreateCall(CGM.getIntrinsic(Intrinsic::frameaddress),
                         ConstantInt::get(Int32Ty, 0));
    Builder.CreateStore(FrameAddr, Buf);

    // Store the stack pointer to the setjmp buffer.
    Value *StackAddr =
      Builder.CreateCall(CGM.getIntrinsic(Intrinsic::stacksave));
    Value *StackSaveSlot =
      Builder.CreateGEP(Buf, ConstantInt::get(Int32Ty, 2));
    Builder.CreateStore(StackAddr, StackSaveSlot);

    // Call LLVM's EH setjmp, which is lightweight.
    Value *F = CGM.getIntrinsic(Intrinsic::eh_sjlj_setjmp);
    Buf = Builder.CreateBitCast(Buf, llvm::Type::getInt8PtrTy(VMContext));
    return RValue::get(Builder.CreateCall(F, Buf));
  }
  case Builtin::BI__builtin_longjmp: {
    Value *Buf = EmitScalarExpr(E->getArg(0));
    Buf = Builder.CreateBitCast(Buf, llvm::Type::getInt8PtrTy(VMContext));

    // Call LLVM's EH longjmp, which is lightweight.
    Builder.CreateCall(CGM.getIntrinsic(Intrinsic::eh_sjlj_longjmp), Buf);

    // longjmp doesn't return; mark this as unreachable
    Value *V = Builder.CreateUnreachable();
    Builder.ClearInsertionPoint();
    return RValue::get(V);
  }
  case Builtin::BI__sync_fetch_and_add:
  case Builtin::BI__sync_fetch_and_sub:
  case Builtin::BI__sync_fetch_and_or:
  case Builtin::BI__sync_fetch_and_and:
  case Builtin::BI__sync_fetch_and_xor:
  case Builtin::BI__sync_add_and_fetch:
  case Builtin::BI__sync_sub_and_fetch:
  case Builtin::BI__sync_and_and_fetch:
  case Builtin::BI__sync_or_and_fetch:
  case Builtin::BI__sync_xor_and_fetch:
  case Builtin::BI__sync_val_compare_and_swap:
  case Builtin::BI__sync_bool_compare_and_swap:
  case Builtin::BI__sync_lock_test_and_set:
  case Builtin::BI__sync_lock_release:
    assert(0 && "Shouldn't make it through sema");
  case Builtin::BI__sync_fetch_and_add_1:
  case Builtin::BI__sync_fetch_and_add_2:
  case Builtin::BI__sync_fetch_and_add_4:
  case Builtin::BI__sync_fetch_and_add_8:
  case Builtin::BI__sync_fetch_and_add_16:
    return EmitBinaryAtomic(*this, Intrinsic::atomic_load_add, E);
  case Builtin::BI__sync_fetch_and_sub_1:
  case Builtin::BI__sync_fetch_and_sub_2:
  case Builtin::BI__sync_fetch_and_sub_4:
  case Builtin::BI__sync_fetch_and_sub_8:
  case Builtin::BI__sync_fetch_and_sub_16:
    return EmitBinaryAtomic(*this, Intrinsic::atomic_load_sub, E);
  case Builtin::BI__sync_fetch_and_or_1:
  case Builtin::BI__sync_fetch_and_or_2:
  case Builtin::BI__sync_fetch_and_or_4:
  case Builtin::BI__sync_fetch_and_or_8:
  case Builtin::BI__sync_fetch_and_or_16:
    return EmitBinaryAtomic(*this, Intrinsic::atomic_load_or, E);
  case Builtin::BI__sync_fetch_and_and_1:
  case Builtin::BI__sync_fetch_and_and_2:
  case Builtin::BI__sync_fetch_and_and_4:
  case Builtin::BI__sync_fetch_and_and_8:
  case Builtin::BI__sync_fetch_and_and_16:
    return EmitBinaryAtomic(*this, Intrinsic::atomic_load_and, E);
  case Builtin::BI__sync_fetch_and_xor_1:
  case Builtin::BI__sync_fetch_and_xor_2:
  case Builtin::BI__sync_fetch_and_xor_4:
  case Builtin::BI__sync_fetch_and_xor_8:
  case Builtin::BI__sync_fetch_and_xor_16:
    return EmitBinaryAtomic(*this, Intrinsic::atomic_load_xor, E);

  // Clang extensions: not overloaded yet.
  case Builtin::BI__sync_fetch_and_min:
    return EmitBinaryAtomic(*this, Intrinsic::atomic_load_min, E);
  case Builtin::BI__sync_fetch_and_max:
    return EmitBinaryAtomic(*this, Intrinsic::atomic_load_max, E);
  case Builtin::BI__sync_fetch_and_umin:
    return EmitBinaryAtomic(*this, Intrinsic::atomic_load_umin, E);
  case Builtin::BI__sync_fetch_and_umax:
    return EmitBinaryAtomic(*this, Intrinsic::atomic_load_umax, E);

  case Builtin::BI__sync_add_and_fetch_1:
  case Builtin::BI__sync_add_and_fetch_2:
  case Builtin::BI__sync_add_and_fetch_4:
  case Builtin::BI__sync_add_and_fetch_8:
  case Builtin::BI__sync_add_and_fetch_16:
    return EmitBinaryAtomicPost(*this, Intrinsic::atomic_load_add, E,
                                llvm::Instruction::Add);
  case Builtin::BI__sync_sub_and_fetch_1:
  case Builtin::BI__sync_sub_and_fetch_2:
  case Builtin::BI__sync_sub_and_fetch_4:
  case Builtin::BI__sync_sub_and_fetch_8:
  case Builtin::BI__sync_sub_and_fetch_16:
    return EmitBinaryAtomicPost(*this, Intrinsic::atomic_load_sub, E,
                                llvm::Instruction::Sub);
  case Builtin::BI__sync_and_and_fetch_1:
  case Builtin::BI__sync_and_and_fetch_2:
  case Builtin::BI__sync_and_and_fetch_4:
  case Builtin::BI__sync_and_and_fetch_8:
  case Builtin::BI__sync_and_and_fetch_16:
    return EmitBinaryAtomicPost(*this, Intrinsic::atomic_load_and, E,
                                llvm::Instruction::And);
  case Builtin::BI__sync_or_and_fetch_1:
  case Builtin::BI__sync_or_and_fetch_2:
  case Builtin::BI__sync_or_and_fetch_4:
  case Builtin::BI__sync_or_and_fetch_8:
  case Builtin::BI__sync_or_and_fetch_16:
    return EmitBinaryAtomicPost(*this, Intrinsic::atomic_load_or, E,
                                llvm::Instruction::Or);
  case Builtin::BI__sync_xor_and_fetch_1:
  case Builtin::BI__sync_xor_and_fetch_2:
  case Builtin::BI__sync_xor_and_fetch_4:
  case Builtin::BI__sync_xor_and_fetch_8:
  case Builtin::BI__sync_xor_and_fetch_16:
    return EmitBinaryAtomicPost(*this, Intrinsic::atomic_load_xor, E,
                                llvm::Instruction::Xor);

  case Builtin::BI__sync_val_compare_and_swap_1:
  case Builtin::BI__sync_val_compare_and_swap_2:
  case Builtin::BI__sync_val_compare_and_swap_4:
  case Builtin::BI__sync_val_compare_and_swap_8:
  case Builtin::BI__sync_val_compare_and_swap_16: {
    QualType T = E->getType();
    llvm::Value *DestPtr = CGF.EmitScalarExpr(E->getArg(0));
    unsigned AddrSpace =
      cast<llvm::PointerType>(DestPtr->getType())->getAddressSpace();

    const llvm::IntegerType *IntType =
      llvm::IntegerType::get(CGF.getLLVMContext(),
                             CGF.getContext().getTypeSize(T));
    const llvm::Type *IntPtrType = IntType->getPointerTo(AddrSpace);
    const llvm::Type *IntrinsicTypes[2] = { IntType, IntPtrType };
    Value *AtomF = CGM.getIntrinsic(Intrinsic::atomic_cmp_swap,
                                    IntrinsicTypes, 2);

    Value *Args[3];
    Args[0] = Builder.CreateBitCast(DestPtr, IntPtrType);
    Args[1] = CGF.EmitScalarExpr(E->getArg(1));
    const llvm::Type *ValueType = Args[1]->getType();
    Args[1] = EmitToInt(CGF, Args[1], T, IntType);
    Args[2] = EmitToInt(CGF, CGF.EmitScalarExpr(E->getArg(2)), T, IntType);

    Value *Result = EmitCallWithBarrier(CGF, AtomF, Args, Args + 3);
    Result = EmitFromInt(CGF, Result, T, ValueType);
    return RValue::get(Result);
  }

  case Builtin::BI__sync_bool_compare_and_swap_1:
  case Builtin::BI__sync_bool_compare_and_swap_2:
  case Builtin::BI__sync_bool_compare_and_swap_4:
  case Builtin::BI__sync_bool_compare_and_swap_8:
  case Builtin::BI__sync_bool_compare_and_swap_16: {
    QualType T = E->getArg(1)->getType();
    llvm::Value *DestPtr = CGF.EmitScalarExpr(E->getArg(0));
    unsigned AddrSpace =
      cast<llvm::PointerType>(DestPtr->getType())->getAddressSpace();

    const llvm::IntegerType *IntType =
      llvm::IntegerType::get(CGF.getLLVMContext(),
                             CGF.getContext().getTypeSize(T));
    const llvm::Type *IntPtrType = IntType->getPointerTo(AddrSpace);
    const llvm::Type *IntrinsicTypes[2] = { IntType, IntPtrType };
    Value *AtomF = CGM.getIntrinsic(Intrinsic::atomic_cmp_swap,
                                    IntrinsicTypes, 2);

    Value *Args[3];
    Args[0] = Builder.CreateBitCast(DestPtr, IntPtrType);
    Args[1] = EmitToInt(CGF, CGF.EmitScalarExpr(E->getArg(1)), T, IntType);
    Args[2] = EmitToInt(CGF, CGF.EmitScalarExpr(E->getArg(2)), T, IntType);

    Value *OldVal = Args[1];
    Value *PrevVal = EmitCallWithBarrier(*this, AtomF, Args, Args + 3);
    Value *Result = Builder.CreateICmpEQ(PrevVal, OldVal);
    // zext bool to int.
    Result = Builder.CreateZExt(Result, ConvertType(E->getType()));
    return RValue::get(Result);
  }

  case Builtin::BI__sync_lock_test_and_set_1:
  case Builtin::BI__sync_lock_test_and_set_2:
  case Builtin::BI__sync_lock_test_and_set_4:
  case Builtin::BI__sync_lock_test_and_set_8:
  case Builtin::BI__sync_lock_test_and_set_16:
    return EmitBinaryAtomic(*this, Intrinsic::atomic_swap, E);

  case Builtin::BI__sync_lock_release_1:
  case Builtin::BI__sync_lock_release_2:
  case Builtin::BI__sync_lock_release_4:
  case Builtin::BI__sync_lock_release_8:
  case Builtin::BI__sync_lock_release_16: {
    Value *Ptr = EmitScalarExpr(E->getArg(0));
    const llvm::Type *ElTy =
      cast<llvm::PointerType>(Ptr->getType())->getElementType();
    llvm::StoreInst *Store =
      Builder.CreateStore(llvm::Constant::getNullValue(ElTy), Ptr);
    Store->setVolatile(true);
    return RValue::get(0);
  }

  case Builtin::BI__sync_synchronize: {
    // We assume like gcc appears to, that this only applies to cached memory.
    EmitMemoryBarrier(*this, true, true, true, true, false);
    return RValue::get(0);
  }

  case Builtin::BI__builtin_llvm_memory_barrier: {
    Value *C[5] = {
      EmitScalarExpr(E->getArg(0)),
      EmitScalarExpr(E->getArg(1)),
      EmitScalarExpr(E->getArg(2)),
      EmitScalarExpr(E->getArg(3)),
      EmitScalarExpr(E->getArg(4))
    };
    Builder.CreateCall(CGM.getIntrinsic(Intrinsic::memory_barrier), C, C + 5);
    return RValue::get(0);
  }

    // Library functions with special handling.
  case Builtin::BIsqrt:
  case Builtin::BIsqrtf:
  case Builtin::BIsqrtl: {
    // TODO: there is currently no set of optimizer flags
    // sufficient for us to rewrite sqrt to @llvm.sqrt.
    // -fmath-errno=0 is not good enough; we need finiteness.
    // We could probably precondition the call with an ult
    // against 0, but is that worth the complexity?
    break;
  }

  case Builtin::BIpow:
  case Builtin::BIpowf:
  case Builtin::BIpowl: {
    // Rewrite sqrt to intrinsic if allowed.
    if (!FD->hasAttr<ConstAttr>())
      break;
    Value *Base = EmitScalarExpr(E->getArg(0));
    Value *Exponent = EmitScalarExpr(E->getArg(1));
    const llvm::Type *ArgType = Base->getType();
    Value *F = CGM.getIntrinsic(Intrinsic::pow, &ArgType, 1);
    return RValue::get(Builder.CreateCall2(F, Base, Exponent, "tmp"));
  }

  case Builtin::BI__builtin_signbit:
  case Builtin::BI__builtin_signbitf:
  case Builtin::BI__builtin_signbitl: {
    LLVMContext &C = CGM.getLLVMContext();

    Value *Arg = EmitScalarExpr(E->getArg(0));
    const llvm::Type *ArgTy = Arg->getType();
    if (ArgTy->isPPC_FP128Ty())
      break; // FIXME: I'm not sure what the right implementation is here.
    int ArgWidth = ArgTy->getPrimitiveSizeInBits();
    const llvm::Type *ArgIntTy = llvm::IntegerType::get(C, ArgWidth);
    Value *BCArg = Builder.CreateBitCast(Arg, ArgIntTy);
    Value *ZeroCmp = llvm::Constant::getNullValue(ArgIntTy);
    Value *Result = Builder.CreateICmpSLT(BCArg, ZeroCmp);
    return RValue::get(Builder.CreateZExt(Result, ConvertType(E->getType())));
  }
  }

  // If this is an alias for a libm function (e.g. __builtin_sin) turn it into
  // that function.
  if (getContext().BuiltinInfo.isLibFunction(BuiltinID) ||
      getContext().BuiltinInfo.isPredefinedLibFunction(BuiltinID))
    return EmitCall(E->getCallee()->getType(),
                    CGM.getBuiltinLibFunction(FD, BuiltinID),
                    ReturnValueSlot(),
                    E->arg_begin(), E->arg_end());

  // See if we have a target specific intrinsic.
  const char *Name = getContext().BuiltinInfo.GetName(BuiltinID);
  Intrinsic::ID IntrinsicID = Intrinsic::not_intrinsic;
  if (const char *Prefix =
      llvm::Triple::getArchTypePrefix(Target.getTriple().getArch()))
    IntrinsicID = Intrinsic::getIntrinsicForGCCBuiltin(Prefix, Name);

  if (IntrinsicID != Intrinsic::not_intrinsic) {
    SmallVector<Value*, 16> Args;

    // Find out if any arguments are required to be integer constant
    // expressions.
    unsigned ICEArguments = 0;
    ASTContext::GetBuiltinTypeError Error;
    getContext().GetBuiltinType(BuiltinID, Error, &ICEArguments);
    assert(Error == ASTContext::GE_None && "Should not codegen an error");

    Function *F = CGM.getIntrinsic(IntrinsicID);
    const llvm::FunctionType *FTy = F->getFunctionType();

    for (unsigned i = 0, e = E->getNumArgs(); i != e; ++i) {
      Value *ArgValue;
      // If this is a normal argument, just emit it as a scalar.
      if ((ICEArguments & (1 << i)) == 0) {
        ArgValue = EmitScalarExpr(E->getArg(i));
      } else {
        // If this is required to be a constant, constant fold it so that we
        // know that the generated intrinsic gets a ConstantInt.
        llvm::APSInt Result;
        bool IsConst = E->getArg(i)->isIntegerConstantExpr(Result,getContext());
        assert(IsConst && "Constant arg isn't actually constant?");
        (void)IsConst;
        ArgValue = llvm::ConstantInt::get(VMContext, Result);
      }

      // If the intrinsic arg type is different from the builtin arg type
      // we need to do a bit cast.
      const llvm::Type *PTy = FTy->getParamType(i);
      if (PTy != ArgValue->getType()) {
        assert(PTy->canLosslesslyBitCastTo(FTy->getParamType(i)) &&
               "Must be able to losslessly bit cast to param");
        ArgValue = Builder.CreateBitCast(ArgValue, PTy);
      }

      Args.push_back(ArgValue);
    }

    Value *V = Builder.CreateCall(F, Args.data(), Args.data() + Args.size());
    QualType BuiltinRetType = E->getType();

    const llvm::Type *RetTy = llvm::Type::getVoidTy(VMContext);
    if (!BuiltinRetType->isVoidType()) RetTy = ConvertType(BuiltinRetType);

    if (RetTy != V->getType()) {
      assert(V->getType()->canLosslesslyBitCastTo(RetTy) &&
             "Must be able to losslessly bit cast result type");
      V = Builder.CreateBitCast(V, RetTy);
    }

    return RValue::get(V);
  }

  // See if we have a target specific builtin that needs to be lowered.
  if (Value *V = EmitTargetBuiltinExpr(BuiltinID, E))
    return RValue::get(V);

  ErrorUnsupported(E, "builtin function");

  // Unknown builtin, for now just dump it out and return undef.
  if (hasAggregateLLVMType(E->getType()))
    return RValue::getAggregate(CreateMemTemp(E->getType()));
  return RValue::get(llvm::UndefValue::get(ConvertType(E->getType())));
}

Value *CodeGenFunction::EmitTargetBuiltinExpr(unsigned BuiltinID,
                                              const CallExpr *E) {
  switch (Target.getTriple().getArch()) {
  case llvm::Triple::arm:
  case llvm::Triple::thumb:
    return EmitARMBuiltinExpr(BuiltinID, E);
  case llvm::Triple::x86:
  case llvm::Triple::x86_64:
    return EmitX86BuiltinExpr(BuiltinID, E);
  case llvm::Triple::ppc:
  case llvm::Triple::ppc64:
    return EmitPPCBuiltinExpr(BuiltinID, E);
  default:
    return 0;
  }
}

const llvm::VectorType *GetNeonType(LLVMContext &C, unsigned type, bool q) {
  switch (type) {
    default: break;
    case 0:
    case 5: return llvm::VectorType::get(llvm::Type::getInt8Ty(C), 8 << (int)q);
    case 6:
    case 7:
    case 1: return llvm::VectorType::get(llvm::Type::getInt16Ty(C),4 << (int)q);
    case 2: return llvm::VectorType::get(llvm::Type::getInt32Ty(C),2 << (int)q);
    case 3: return llvm::VectorType::get(llvm::Type::getInt64Ty(C),1 << (int)q);
    case 4: return llvm::VectorType::get(llvm::Type::getFloatTy(C),2 << (int)q);
  };
  return 0;
}

Value *CodeGenFunction::EmitNeonSplat(Value *V, Constant *C) {
  unsigned nElts = cast<llvm::VectorType>(V->getType())->getNumElements();
  SmallVector<Constant*, 16> Indices(nElts, C);
  Value* SV = llvm::ConstantVector::get(Indices.begin(), Indices.size());
  return Builder.CreateShuffleVector(V, V, SV, "lane");
}

Value *CodeGenFunction::EmitNeonCall(Function *F, SmallVectorImpl<Value*> &Ops,
                                     const char *name,
                                     unsigned shift, bool rightshift) {
  unsigned j = 0;
  for (Function::const_arg_iterator ai = F->arg_begin(), ae = F->arg_end();
       ai != ae; ++ai, ++j)
    if (shift > 0 && shift == j)
      Ops[j] = EmitNeonShiftVector(Ops[j], ai->getType(), rightshift);
    else
      Ops[j] = Builder.CreateBitCast(Ops[j], ai->getType(), name);

  return Builder.CreateCall(F, Ops.begin(), Ops.end(), name);
}

Value *CodeGenFunction::EmitNeonShiftVector(Value *V, const llvm::Type *Ty,
                                            bool neg) {
  ConstantInt *CI = cast<ConstantInt>(V);
  int SV = CI->getSExtValue();

  const llvm::VectorType *VTy = cast<llvm::VectorType>(Ty);
  llvm::Constant *C = ConstantInt::get(VTy->getElementType(), neg ? -SV : SV);
  SmallVector<llvm::Constant*, 16> CV(VTy->getNumElements(), C);
  return llvm::ConstantVector::get(CV.begin(), CV.size());
}

/// GetPointeeAlignment - Given an expression with a pointer type, find the
/// alignment of the type referenced by the pointer.  Skip over implicit
/// casts.
static Value *GetPointeeAlignment(CodeGenFunction &CGF, const Expr *Addr) {
  unsigned Align = 1;
  // Check if the type is a pointer.  The implicit cast operand might not be.
  while (Addr->getType()->isPointerType()) {
    QualType PtTy = Addr->getType()->getPointeeType();
    unsigned NewA = CGF.getContext().getTypeAlignInChars(PtTy).getQuantity();
    if (NewA > Align)
      Align = NewA;

    // If the address is an implicit cast, repeat with the cast operand.
    if (const ImplicitCastExpr *CastAddr = dyn_cast<ImplicitCastExpr>(Addr)) {
      Addr = CastAddr->getSubExpr();
      continue;
    }
    break;
  }
  return llvm::ConstantInt::get(CGF.Int32Ty, Align);
}

Value *CodeGenFunction::EmitARMBuiltinExpr(unsigned BuiltinID,
                                           const CallExpr *E) {
  if (BuiltinID == ARM::BI__clear_cache) {
    const FunctionDecl *FD = E->getDirectCallee();
    Value *a = EmitScalarExpr(E->getArg(0));
    Value *b = EmitScalarExpr(E->getArg(1));
    const llvm::Type *Ty = CGM.getTypes().ConvertType(FD->getType());
    const llvm::FunctionType *FTy = cast<llvm::FunctionType>(Ty);
    llvm::StringRef Name = FD->getName();
    return Builder.CreateCall2(CGM.CreateRuntimeFunction(FTy, Name),
                               a, b);
  }

  llvm::SmallVector<Value*, 4> Ops;
  for (unsigned i = 0, e = E->getNumArgs() - 1; i != e; i++)
    Ops.push_back(EmitScalarExpr(E->getArg(i)));

  llvm::APSInt Result;
  const Expr *Arg = E->getArg(E->getNumArgs()-1);
  if (!Arg->isIntegerConstantExpr(Result, getContext()))
    return 0;

  if (BuiltinID == ARM::BI__builtin_arm_vcvtr_f ||
      BuiltinID == ARM::BI__builtin_arm_vcvtr_d) {
    // Determine the overloaded type of this builtin.
    const llvm::Type *Ty;
    if (BuiltinID == ARM::BI__builtin_arm_vcvtr_f)
      Ty = llvm::Type::getFloatTy(VMContext);
    else
      Ty = llvm::Type::getDoubleTy(VMContext);

    // Determine whether this is an unsigned conversion or not.
    bool usgn = Result.getZExtValue() == 1;
    unsigned Int = usgn ? Intrinsic::arm_vcvtru : Intrinsic::arm_vcvtr;

    // Call the appropriate intrinsic.
    Function *F = CGM.getIntrinsic(Int, &Ty, 1);
    return Builder.CreateCall(F, Ops.begin(), Ops.end(), "vcvtr");
  }

  // Determine the type of this overloaded NEON intrinsic.
  unsigned type = Result.getZExtValue();
  bool usgn = type & 0x08;
  bool quad = type & 0x10;
  bool poly = (type & 0x7) == 5 || (type & 0x7) == 6;
  (void)poly;  // Only used in assert()s.
  bool rightShift = false;

  const llvm::VectorType *VTy = GetNeonType(VMContext, type & 0x7, quad);
  const llvm::Type *Ty = VTy;
  if (!Ty)
    return 0;

  unsigned Int;
  switch (BuiltinID) {
  default: return 0;
  case ARM::BI__builtin_neon_vabd_v:
  case ARM::BI__builtin_neon_vabdq_v:
    Int = usgn ? Intrinsic::arm_neon_vabdu : Intrinsic::arm_neon_vabds;
    return EmitNeonCall(CGM.getIntrinsic(Int, &Ty, 1), Ops, "vabd");
  case ARM::BI__builtin_neon_vabs_v:
  case ARM::BI__builtin_neon_vabsq_v:
    return EmitNeonCall(CGM.getIntrinsic(Intrinsic::arm_neon_vabs, &Ty, 1),
                        Ops, "vabs");
  case ARM::BI__builtin_neon_vaddhn_v:
    return EmitNeonCall(CGM.getIntrinsic(Intrinsic::arm_neon_vaddhn, &Ty, 1),
                        Ops, "vaddhn");
  case ARM::BI__builtin_neon_vcale_v:
    std::swap(Ops[0], Ops[1]);
  case ARM::BI__builtin_neon_vcage_v: {
    Function *F = CGM.getIntrinsic(Intrinsic::arm_neon_vacged);
    return EmitNeonCall(F, Ops, "vcage");
  }
  case ARM::BI__builtin_neon_vcaleq_v:
    std::swap(Ops[0], Ops[1]);
  case ARM::BI__builtin_neon_vcageq_v: {
    Function *F = CGM.getIntrinsic(Intrinsic::arm_neon_vacgeq);
    return EmitNeonCall(F, Ops, "vcage");
  }
  case ARM::BI__builtin_neon_vcalt_v:
    std::swap(Ops[0], Ops[1]);
  case ARM::BI__builtin_neon_vcagt_v: {
    Function *F = CGM.getIntrinsic(Intrinsic::arm_neon_vacgtd);
    return EmitNeonCall(F, Ops, "vcagt");
  }
  case ARM::BI__builtin_neon_vcaltq_v:
    std::swap(Ops[0], Ops[1]);
  case ARM::BI__builtin_neon_vcagtq_v: {
    Function *F = CGM.getIntrinsic(Intrinsic::arm_neon_vacgtq);
    return EmitNeonCall(F, Ops, "vcagt");
  }
  case ARM::BI__builtin_neon_vcls_v:
  case ARM::BI__builtin_neon_vclsq_v: {
    Function *F = CGM.getIntrinsic(Intrinsic::arm_neon_vcls, &Ty, 1);
    return EmitNeonCall(F, Ops, "vcls");
  }
  case ARM::BI__builtin_neon_vclz_v:
  case ARM::BI__builtin_neon_vclzq_v: {
    Function *F = CGM.getIntrinsic(Intrinsic::arm_neon_vclz, &Ty, 1);
    return EmitNeonCall(F, Ops, "vclz");
  }
  case ARM::BI__builtin_neon_vcnt_v:
  case ARM::BI__builtin_neon_vcntq_v: {
    Function *F = CGM.getIntrinsic(Intrinsic::arm_neon_vcnt, &Ty, 1);
    return EmitNeonCall(F, Ops, "vcnt");
  }
  case ARM::BI__builtin_neon_vcvt_f16_v: {
    assert((type & 0x7) == 7 && !quad && "unexpected vcvt_f16_v builtin");
    Function *F = CGM.getIntrinsic(Intrinsic::arm_neon_vcvtfp2hf);
    return EmitNeonCall(F, Ops, "vcvt");
  }
  case ARM::BI__builtin_neon_vcvt_f32_f16: {
    assert((type & 0x7) == 7 && !quad && "unexpected vcvt_f32_f16 builtin");
    Function *F = CGM.getIntrinsic(Intrinsic::arm_neon_vcvthf2fp);
    return EmitNeonCall(F, Ops, "vcvt");
  }
  case ARM::BI__builtin_neon_vcvt_f32_v:
  case ARM::BI__builtin_neon_vcvtq_f32_v: {
    Ops[0] = Builder.CreateBitCast(Ops[0], Ty);
    Ty = GetNeonType(VMContext, 4, quad);
    return usgn ? Builder.CreateUIToFP(Ops[0], Ty, "vcvt")
                : Builder.CreateSIToFP(Ops[0], Ty, "vcvt");
  }
  case ARM::BI__builtin_neon_vcvt_s32_v:
  case ARM::BI__builtin_neon_vcvt_u32_v:
  case ARM::BI__builtin_neon_vcvtq_s32_v:
  case ARM::BI__builtin_neon_vcvtq_u32_v: {
    Ops[0] = Builder.CreateBitCast(Ops[0], GetNeonType(VMContext, 4, quad));
    return usgn ? Builder.CreateFPToUI(Ops[0], Ty, "vcvt")
                : Builder.CreateFPToSI(Ops[0], Ty, "vcvt");
  }
  case ARM::BI__builtin_neon_vcvt_n_f32_v:
  case ARM::BI__builtin_neon_vcvtq_n_f32_v: {
    const llvm::Type *Tys[2] = { GetNeonType(VMContext, 4, quad), Ty };
    Int = usgn ? Intrinsic::arm_neon_vcvtfxu2fp : Intrinsic::arm_neon_vcvtfxs2fp;
    Function *F = CGM.getIntrinsic(Int, Tys, 2);
    return EmitNeonCall(F, Ops, "vcvt_n");
  }
  case ARM::BI__builtin_neon_vcvt_n_s32_v:
  case ARM::BI__builtin_neon_vcvt_n_u32_v:
  case ARM::BI__builtin_neon_vcvtq_n_s32_v:
  case ARM::BI__builtin_neon_vcvtq_n_u32_v: {
    const llvm::Type *Tys[2] = { Ty, GetNeonType(VMContext, 4, quad) };
    Int = usgn ? Intrinsic::arm_neon_vcvtfp2fxu : Intrinsic::arm_neon_vcvtfp2fxs;
    Function *F = CGM.getIntrinsic(Int, Tys, 2);
    return EmitNeonCall(F, Ops, "vcvt_n");
  }
  case ARM::BI__builtin_neon_vext_v:
  case ARM::BI__builtin_neon_vextq_v: {
    ConstantInt *C = dyn_cast<ConstantInt>(Ops[2]);
    int CV = C->getSExtValue();
    SmallVector<Constant*, 16> Indices;
    for (unsigned i = 0, e = VTy->getNumElements(); i != e; ++i)
      Indices.push_back(ConstantInt::get(Int32Ty, i+CV));

    Ops[0] = Builder.CreateBitCast(Ops[0], Ty);
    Ops[1] = Builder.CreateBitCast(Ops[1], Ty);
    Value* SV = llvm::ConstantVector::get(Indices.begin(), Indices.size());
    return Builder.CreateShuffleVector(Ops[0], Ops[1], SV, "vext");
  }
  case ARM::BI__builtin_neon_vget_lane_i8:
  case ARM::BI__builtin_neon_vget_lane_i16:
  case ARM::BI__builtin_neon_vget_lane_i32:
  case ARM::BI__builtin_neon_vget_lane_i64:
  case ARM::BI__builtin_neon_vget_lane_f32:
  case ARM::BI__builtin_neon_vgetq_lane_i8:
  case ARM::BI__builtin_neon_vgetq_lane_i16:
  case ARM::BI__builtin_neon_vgetq_lane_i32:
  case ARM::BI__builtin_neon_vgetq_lane_i64:
  case ARM::BI__builtin_neon_vgetq_lane_f32:
    return Builder.CreateExtractElement(Ops[0], EmitScalarExpr(E->getArg(1)),
                                        "vget_lane");
  case ARM::BI__builtin_neon_vhadd_v:
  case ARM::BI__builtin_neon_vhaddq_v:
    Int = usgn ? Intrinsic::arm_neon_vhaddu : Intrinsic::arm_neon_vhadds;
    return EmitNeonCall(CGM.getIntrinsic(Int, &Ty, 1), Ops, "vhadd");
  case ARM::BI__builtin_neon_vhsub_v:
  case ARM::BI__builtin_neon_vhsubq_v:
    Int = usgn ? Intrinsic::arm_neon_vhsubu : Intrinsic::arm_neon_vhsubs;
    return EmitNeonCall(CGM.getIntrinsic(Int, &Ty, 1), Ops, "vhsub");
  case ARM::BI__builtin_neon_vld1_v:
  case ARM::BI__builtin_neon_vld1q_v:
    Ops.push_back(GetPointeeAlignment(*this, E->getArg(0)));
    return EmitNeonCall(CGM.getIntrinsic(Intrinsic::arm_neon_vld1, &Ty, 1),
                        Ops, "vld1");
  case ARM::BI__builtin_neon_vld1_lane_v:
  case ARM::BI__builtin_neon_vld1q_lane_v:
    Ops[1] = Builder.CreateBitCast(Ops[1], Ty);
    Ty = llvm::PointerType::getUnqual(VTy->getElementType());
    Ops[0] = Builder.CreateBitCast(Ops[0], Ty);
    Ops[0] = Builder.CreateLoad(Ops[0]);
    return Builder.CreateInsertElement(Ops[1], Ops[0], Ops[2], "vld1_lane");
  case ARM::BI__builtin_neon_vld1_dup_v:
  case ARM::BI__builtin_neon_vld1q_dup_v: {
    Value *V = UndefValue::get(Ty);
    Ty = llvm::PointerType::getUnqual(VTy->getElementType());
    Ops[0] = Builder.CreateBitCast(Ops[0], Ty);
    Ops[0] = Builder.CreateLoad(Ops[0]);
    llvm::Constant *CI = ConstantInt::get(Int32Ty, 0);
    Ops[0] = Builder.CreateInsertElement(V, Ops[0], CI);
    return EmitNeonSplat(Ops[0], CI);
  }
  case ARM::BI__builtin_neon_vld2_v:
  case ARM::BI__builtin_neon_vld2q_v: {
    Function *F = CGM.getIntrinsic(Intrinsic::arm_neon_vld2, &Ty, 1);
    Value *Align = GetPointeeAlignment(*this, E->getArg(1));
    Ops[1] = Builder.CreateCall2(F, Ops[1], Align, "vld2");
    Ty = llvm::PointerType::getUnqual(Ops[1]->getType());
    Ops[0] = Builder.CreateBitCast(Ops[0], Ty);
    return Builder.CreateStore(Ops[1], Ops[0]);
  }
  case ARM::BI__builtin_neon_vld3_v:
  case ARM::BI__builtin_neon_vld3q_v: {
    Function *F = CGM.getIntrinsic(Intrinsic::arm_neon_vld3, &Ty, 1);
    Value *Align = GetPointeeAlignment(*this, E->getArg(1));
    Ops[1] = Builder.CreateCall2(F, Ops[1], Align, "vld3");
    Ty = llvm::PointerType::getUnqual(Ops[1]->getType());
    Ops[0] = Builder.CreateBitCast(Ops[0], Ty);
    return Builder.CreateStore(Ops[1], Ops[0]);
  }
  case ARM::BI__builtin_neon_vld4_v:
  case ARM::BI__builtin_neon_vld4q_v: {
    Function *F = CGM.getIntrinsic(Intrinsic::arm_neon_vld4, &Ty, 1);
    Value *Align = GetPointeeAlignment(*this, E->getArg(1));
    Ops[1] = Builder.CreateCall2(F, Ops[1], Align, "vld4");
    Ty = llvm::PointerType::getUnqual(Ops[1]->getType());
    Ops[0] = Builder.CreateBitCast(Ops[0], Ty);
    return Builder.CreateStore(Ops[1], Ops[0]);
  }
  case ARM::BI__builtin_neon_vld2_lane_v:
  case ARM::BI__builtin_neon_vld2q_lane_v: {
    Function *F = CGM.getIntrinsic(Intrinsic::arm_neon_vld2lane, &Ty, 1);
    Ops[2] = Builder.CreateBitCast(Ops[2], Ty);
    Ops[3] = Builder.CreateBitCast(Ops[3], Ty);
    Ops.push_back(GetPointeeAlignment(*this, E->getArg(1)));
    Ops[1] = Builder.CreateCall(F, Ops.begin() + 1, Ops.end(), "vld2_lane");
    Ty = llvm::PointerType::getUnqual(Ops[1]->getType());
    Ops[0] = Builder.CreateBitCast(Ops[0], Ty);
    return Builder.CreateStore(Ops[1], Ops[0]);
  }
  case ARM::BI__builtin_neon_vld3_lane_v:
  case ARM::BI__builtin_neon_vld3q_lane_v: {
    Function *F = CGM.getIntrinsic(Intrinsic::arm_neon_vld3lane, &Ty, 1);
    Ops[2] = Builder.CreateBitCast(Ops[2], Ty);
    Ops[3] = Builder.CreateBitCast(Ops[3], Ty);
    Ops[4] = Builder.CreateBitCast(Ops[4], Ty);
    Ops.push_back(GetPointeeAlignment(*this, E->getArg(1)));
    Ops[1] = Builder.CreateCall(F, Ops.begin() + 1, Ops.end(), "vld3_lane");
    Ty = llvm::PointerType::getUnqual(Ops[1]->getType());
    Ops[0] = Builder.CreateBitCast(Ops[0], Ty);
    return Builder.CreateStore(Ops[1], Ops[0]);
  }
  case ARM::BI__builtin_neon_vld4_lane_v:
  case ARM::BI__builtin_neon_vld4q_lane_v: {
    Function *F = CGM.getIntrinsic(Intrinsic::arm_neon_vld4lane, &Ty, 1);
    Ops[2] = Builder.CreateBitCast(Ops[2], Ty);
    Ops[3] = Builder.CreateBitCast(Ops[3], Ty);
    Ops[4] = Builder.CreateBitCast(Ops[4], Ty);
    Ops[5] = Builder.CreateBitCast(Ops[5], Ty);
    Ops.push_back(GetPointeeAlignment(*this, E->getArg(1)));
    Ops[1] = Builder.CreateCall(F, Ops.begin() + 1, Ops.end(), "vld3_lane");
    Ty = llvm::PointerType::getUnqual(Ops[1]->getType());
    Ops[0] = Builder.CreateBitCast(Ops[0], Ty);
    return Builder.CreateStore(Ops[1], Ops[0]);
  }
  case ARM::BI__builtin_neon_vld2_dup_v:
  case ARM::BI__builtin_neon_vld3_dup_v:
  case ARM::BI__builtin_neon_vld4_dup_v: {
    // Handle 64-bit elements as a special-case.  There is no "dup" needed.
    if (VTy->getElementType()->getPrimitiveSizeInBits() == 64) {
      switch (BuiltinID) {
      case ARM::BI__builtin_neon_vld2_dup_v:
        Int = Intrinsic::arm_neon_vld2;
        break;
      case ARM::BI__builtin_neon_vld3_dup_v:
        Int = Intrinsic::arm_neon_vld2;
        break;
      case ARM::BI__builtin_neon_vld4_dup_v:
        Int = Intrinsic::arm_neon_vld2;
        break;
      default: assert(0 && "unknown vld_dup intrinsic?");
      }
      Function *F = CGM.getIntrinsic(Int, &Ty, 1);
      Value *Align = GetPointeeAlignment(*this, E->getArg(1));
      Ops[1] = Builder.CreateCall2(F, Ops[1], Align, "vld_dup");
      Ty = llvm::PointerType::getUnqual(Ops[1]->getType());
      Ops[0] = Builder.CreateBitCast(Ops[0], Ty);
      return Builder.CreateStore(Ops[1], Ops[0]);
    }
    switch (BuiltinID) {
    case ARM::BI__builtin_neon_vld2_dup_v:
      Int = Intrinsic::arm_neon_vld2lane;
      break;
    case ARM::BI__builtin_neon_vld3_dup_v:
      Int = Intrinsic::arm_neon_vld2lane;
      break;
    case ARM::BI__builtin_neon_vld4_dup_v:
      Int = Intrinsic::arm_neon_vld2lane;
      break;
    default: assert(0 && "unknown vld_dup intrinsic?");
    }
    Function *F = CGM.getIntrinsic(Int, &Ty, 1);
    const llvm::StructType *STy = cast<llvm::StructType>(F->getReturnType());

    SmallVector<Value*, 6> Args;
    Args.push_back(Ops[1]);
    Args.append(STy->getNumElements(), UndefValue::get(Ty));

    llvm::Constant *CI = ConstantInt::get(Int32Ty, 0);
    Args.push_back(CI);
    Args.push_back(GetPointeeAlignment(*this, E->getArg(1)));

    Ops[1] = Builder.CreateCall(F, Args.begin(), Args.end(), "vld_dup");
    // splat lane 0 to all elts in each vector of the result.
    for (unsigned i = 0, e = STy->getNumElements(); i != e; ++i) {
      Value *Val = Builder.CreateExtractValue(Ops[1], i);
      Value *Elt = Builder.CreateBitCast(Val, Ty);
      Elt = EmitNeonSplat(Elt, CI);
      Elt = Builder.CreateBitCast(Elt, Val->getType());
      Ops[1] = Builder.CreateInsertValue(Ops[1], Elt, i);
    }
    Ty = llvm::PointerType::getUnqual(Ops[1]->getType());
    Ops[0] = Builder.CreateBitCast(Ops[0], Ty);
    return Builder.CreateStore(Ops[1], Ops[0]);
  }
  case ARM::BI__builtin_neon_vmax_v:
  case ARM::BI__builtin_neon_vmaxq_v:
    Int = usgn ? Intrinsic::arm_neon_vmaxu : Intrinsic::arm_neon_vmaxs;
    return EmitNeonCall(CGM.getIntrinsic(Int, &Ty, 1), Ops, "vmax");
  case ARM::BI__builtin_neon_vmin_v:
  case ARM::BI__builtin_neon_vminq_v:
    Int = usgn ? Intrinsic::arm_neon_vminu : Intrinsic::arm_neon_vmins;
    return EmitNeonCall(CGM.getIntrinsic(Int, &Ty, 1), Ops, "vmin");
  case ARM::BI__builtin_neon_vmovl_v: {
    const llvm::Type *DTy =llvm::VectorType::getTruncatedElementVectorType(VTy);
    Ops[0] = Builder.CreateBitCast(Ops[0], DTy);
    if (usgn)
      return Builder.CreateZExt(Ops[0], Ty, "vmovl");
    return Builder.CreateSExt(Ops[0], Ty, "vmovl");
  }
  case ARM::BI__builtin_neon_vmovn_v: {
    const llvm::Type *QTy = llvm::VectorType::getExtendedElementVectorType(VTy);
    Ops[0] = Builder.CreateBitCast(Ops[0], QTy);
    return Builder.CreateTrunc(Ops[0], Ty, "vmovn");
  }
  case ARM::BI__builtin_neon_vmul_v:
  case ARM::BI__builtin_neon_vmulq_v:
    assert(poly && "vmul builtin only supported for polynomial types");
    return EmitNeonCall(CGM.getIntrinsic(Intrinsic::arm_neon_vmulp, &Ty, 1),
                        Ops, "vmul");
  case ARM::BI__builtin_neon_vmull_v:
    assert(poly && "vmull builtin only supported for polynomial types");
    return EmitNeonCall(CGM.getIntrinsic(Intrinsic::arm_neon_vmullp, &Ty, 1),
                        Ops, "vmull");
  case ARM::BI__builtin_neon_vpadal_v:
  case ARM::BI__builtin_neon_vpadalq_v: {
    Int = usgn ? Intrinsic::arm_neon_vpadalu : Intrinsic::arm_neon_vpadals;
    // The source operand type has twice as many elements of half the size.
    unsigned EltBits = VTy->getElementType()->getPrimitiveSizeInBits();
    const llvm::Type *EltTy = llvm::IntegerType::get(VMContext, EltBits / 2);
    const llvm::Type *NarrowTy =
      llvm::VectorType::get(EltTy, VTy->getNumElements() * 2);
    const llvm::Type *Tys[2] = { Ty, NarrowTy };
    return EmitNeonCall(CGM.getIntrinsic(Int, Tys, 2), Ops, "vpadal");
  }
  case ARM::BI__builtin_neon_vpadd_v:
    return EmitNeonCall(CGM.getIntrinsic(Intrinsic::arm_neon_vpadd, &Ty, 1),
                        Ops, "vpadd");
  case ARM::BI__builtin_neon_vpaddl_v:
  case ARM::BI__builtin_neon_vpaddlq_v: {
    Int = usgn ? Intrinsic::arm_neon_vpaddlu : Intrinsic::arm_neon_vpaddls;
    // The source operand type has twice as many elements of half the size.
    unsigned EltBits = VTy->getElementType()->getPrimitiveSizeInBits();
    const llvm::Type *EltTy = llvm::IntegerType::get(VMContext, EltBits / 2);
    const llvm::Type *NarrowTy =
      llvm::VectorType::get(EltTy, VTy->getNumElements() * 2);
    const llvm::Type *Tys[2] = { Ty, NarrowTy };
    return EmitNeonCall(CGM.getIntrinsic(Int, Tys, 2), Ops, "vpaddl");
  }
  case ARM::BI__builtin_neon_vpmax_v:
    Int = usgn ? Intrinsic::arm_neon_vpmaxu : Intrinsic::arm_neon_vpmaxs;
    return EmitNeonCall(CGM.getIntrinsic(Int, &Ty, 1), Ops, "vpmax");
  case ARM::BI__builtin_neon_vpmin_v:
    Int = usgn ? Intrinsic::arm_neon_vpminu : Intrinsic::arm_neon_vpmins;
    return EmitNeonCall(CGM.getIntrinsic(Int, &Ty, 1), Ops, "vpmin");
  case ARM::BI__builtin_neon_vqabs_v:
  case ARM::BI__builtin_neon_vqabsq_v:
    return EmitNeonCall(CGM.getIntrinsic(Intrinsic::arm_neon_vqabs, &Ty, 1),
                        Ops, "vqabs");
  case ARM::BI__builtin_neon_vqadd_v:
  case ARM::BI__builtin_neon_vqaddq_v:
    Int = usgn ? Intrinsic::arm_neon_vqaddu : Intrinsic::arm_neon_vqadds;
    return EmitNeonCall(CGM.getIntrinsic(Int, &Ty, 1), Ops, "vqadd");
  case ARM::BI__builtin_neon_vqdmlal_v:
    return EmitNeonCall(CGM.getIntrinsic(Intrinsic::arm_neon_vqdmlal, &Ty, 1),
                        Ops, "vqdmlal");
  case ARM::BI__builtin_neon_vqdmlsl_v:
    return EmitNeonCall(CGM.getIntrinsic(Intrinsic::arm_neon_vqdmlsl, &Ty, 1),
                        Ops, "vqdmlsl");
  case ARM::BI__builtin_neon_vqdmulh_v:
  case ARM::BI__builtin_neon_vqdmulhq_v:
    return EmitNeonCall(CGM.getIntrinsic(Intrinsic::arm_neon_vqdmulh, &Ty, 1),
                        Ops, "vqdmulh");
  case ARM::BI__builtin_neon_vqdmull_v:
    return EmitNeonCall(CGM.getIntrinsic(Intrinsic::arm_neon_vqdmull, &Ty, 1),
                        Ops, "vqdmull");
  case ARM::BI__builtin_neon_vqmovn_v:
    Int = usgn ? Intrinsic::arm_neon_vqmovnu : Intrinsic::arm_neon_vqmovns;
    return EmitNeonCall(CGM.getIntrinsic(Int, &Ty, 1), Ops, "vqmovn");
  case ARM::BI__builtin_neon_vqmovun_v:
    return EmitNeonCall(CGM.getIntrinsic(Intrinsic::arm_neon_vqmovnsu, &Ty, 1),
                        Ops, "vqdmull");
  case ARM::BI__builtin_neon_vqneg_v:
  case ARM::BI__builtin_neon_vqnegq_v:
    return EmitNeonCall(CGM.getIntrinsic(Intrinsic::arm_neon_vqneg, &Ty, 1),
                        Ops, "vqneg");
  case ARM::BI__builtin_neon_vqrdmulh_v:
  case ARM::BI__builtin_neon_vqrdmulhq_v:
    return EmitNeonCall(CGM.getIntrinsic(Intrinsic::arm_neon_vqrdmulh, &Ty, 1),
                        Ops, "vqrdmulh");
  case ARM::BI__builtin_neon_vqrshl_v:
  case ARM::BI__builtin_neon_vqrshlq_v:
    Int = usgn ? Intrinsic::arm_neon_vqrshiftu : Intrinsic::arm_neon_vqrshifts;
    return EmitNeonCall(CGM.getIntrinsic(Int, &Ty, 1), Ops, "vqrshl");
  case ARM::BI__builtin_neon_vqrshrn_n_v:
    Int = usgn ? Intrinsic::arm_neon_vqrshiftnu : Intrinsic::arm_neon_vqrshiftns;
    return EmitNeonCall(CGM.getIntrinsic(Int, &Ty, 1), Ops, "vqrshrn_n",
                        1, true);
  case ARM::BI__builtin_neon_vqrshrun_n_v:
    return EmitNeonCall(CGM.getIntrinsic(Intrinsic::arm_neon_vqrshiftnsu, &Ty, 1),
                        Ops, "vqrshrun_n", 1, true);
  case ARM::BI__builtin_neon_vqshl_v:
  case ARM::BI__builtin_neon_vqshlq_v:
    Int = usgn ? Intrinsic::arm_neon_vqshiftu : Intrinsic::arm_neon_vqshifts;
    return EmitNeonCall(CGM.getIntrinsic(Int, &Ty, 1), Ops, "vqshl");
  case ARM::BI__builtin_neon_vqshl_n_v:
  case ARM::BI__builtin_neon_vqshlq_n_v:
    Int = usgn ? Intrinsic::arm_neon_vqshiftu : Intrinsic::arm_neon_vqshifts;
    return EmitNeonCall(CGM.getIntrinsic(Int, &Ty, 1), Ops, "vqshl_n",
                        1, false);
  case ARM::BI__builtin_neon_vqshlu_n_v:
  case ARM::BI__builtin_neon_vqshluq_n_v:
    return EmitNeonCall(CGM.getIntrinsic(Intrinsic::arm_neon_vqshiftsu, &Ty, 1),
                        Ops, "vqshlu", 1, false);
  case ARM::BI__builtin_neon_vqshrn_n_v:
    Int = usgn ? Intrinsic::arm_neon_vqshiftnu : Intrinsic::arm_neon_vqshiftns;
    return EmitNeonCall(CGM.getIntrinsic(Int, &Ty, 1), Ops, "vqshrn_n",
                        1, true);
  case ARM::BI__builtin_neon_vqshrun_n_v:
    return EmitNeonCall(CGM.getIntrinsic(Intrinsic::arm_neon_vqshiftnsu, &Ty, 1),
                        Ops, "vqshrun_n", 1, true);
  case ARM::BI__builtin_neon_vqsub_v:
  case ARM::BI__builtin_neon_vqsubq_v:
    Int = usgn ? Intrinsic::arm_neon_vqsubu : Intrinsic::arm_neon_vqsubs;
    return EmitNeonCall(CGM.getIntrinsic(Int, &Ty, 1), Ops, "vqsub");
  case ARM::BI__builtin_neon_vraddhn_v:
    return EmitNeonCall(CGM.getIntrinsic(Intrinsic::arm_neon_vraddhn, &Ty, 1),
                        Ops, "vraddhn");
  case ARM::BI__builtin_neon_vrecpe_v:
  case ARM::BI__builtin_neon_vrecpeq_v:
    return EmitNeonCall(CGM.getIntrinsic(Intrinsic::arm_neon_vrecpe, &Ty, 1),
                        Ops, "vrecpe");
  case ARM::BI__builtin_neon_vrecps_v:
  case ARM::BI__builtin_neon_vrecpsq_v:
    return EmitNeonCall(CGM.getIntrinsic(Intrinsic::arm_neon_vrecps, &Ty, 1),
                        Ops, "vrecps");
  case ARM::BI__builtin_neon_vrhadd_v:
  case ARM::BI__builtin_neon_vrhaddq_v:
    Int = usgn ? Intrinsic::arm_neon_vrhaddu : Intrinsic::arm_neon_vrhadds;
    return EmitNeonCall(CGM.getIntrinsic(Int, &Ty, 1), Ops, "vrhadd");
  case ARM::BI__builtin_neon_vrshl_v:
  case ARM::BI__builtin_neon_vrshlq_v:
    Int = usgn ? Intrinsic::arm_neon_vrshiftu : Intrinsic::arm_neon_vrshifts;
    return EmitNeonCall(CGM.getIntrinsic(Int, &Ty, 1), Ops, "vrshl");
  case ARM::BI__builtin_neon_vrshrn_n_v:
    return EmitNeonCall(CGM.getIntrinsic(Intrinsic::arm_neon_vrshiftn, &Ty, 1),
                        Ops, "vrshrn_n", 1, true);
  case ARM::BI__builtin_neon_vrshr_n_v:
  case ARM::BI__builtin_neon_vrshrq_n_v:
    Int = usgn ? Intrinsic::arm_neon_vrshiftu : Intrinsic::arm_neon_vrshifts;
    return EmitNeonCall(CGM.getIntrinsic(Int, &Ty, 1), Ops, "vrshr_n", 1, true);
  case ARM::BI__builtin_neon_vrsqrte_v:
  case ARM::BI__builtin_neon_vrsqrteq_v:
    return EmitNeonCall(CGM.getIntrinsic(Intrinsic::arm_neon_vrsqrte, &Ty, 1),
                        Ops, "vrsqrte");
  case ARM::BI__builtin_neon_vrsqrts_v:
  case ARM::BI__builtin_neon_vrsqrtsq_v:
    return EmitNeonCall(CGM.getIntrinsic(Intrinsic::arm_neon_vrsqrts, &Ty, 1),
                        Ops, "vrsqrts");
  case ARM::BI__builtin_neon_vrsra_n_v:
  case ARM::BI__builtin_neon_vrsraq_n_v:
    Ops[0] = Builder.CreateBitCast(Ops[0], Ty);
    Ops[1] = Builder.CreateBitCast(Ops[1], Ty);
    Ops[2] = EmitNeonShiftVector(Ops[2], Ty, true);
    Int = usgn ? Intrinsic::arm_neon_vrshiftu : Intrinsic::arm_neon_vrshifts;
    Ops[1] = Builder.CreateCall2(CGM.getIntrinsic(Int, &Ty, 1), Ops[1], Ops[2]);
    return Builder.CreateAdd(Ops[0], Ops[1], "vrsra_n");
  case ARM::BI__builtin_neon_vrsubhn_v:
    return EmitNeonCall(CGM.getIntrinsic(Intrinsic::arm_neon_vrsubhn, &Ty, 1),
                        Ops, "vrsubhn");
  case ARM::BI__builtin_neon_vset_lane_i8:
  case ARM::BI__builtin_neon_vset_lane_i16:
  case ARM::BI__builtin_neon_vset_lane_i32:
  case ARM::BI__builtin_neon_vset_lane_i64:
  case ARM::BI__builtin_neon_vset_lane_f32:
  case ARM::BI__builtin_neon_vsetq_lane_i8:
  case ARM::BI__builtin_neon_vsetq_lane_i16:
  case ARM::BI__builtin_neon_vsetq_lane_i32:
  case ARM::BI__builtin_neon_vsetq_lane_i64:
  case ARM::BI__builtin_neon_vsetq_lane_f32:
    Ops.push_back(EmitScalarExpr(E->getArg(2)));
    return Builder.CreateInsertElement(Ops[1], Ops[0], Ops[2], "vset_lane");
  case ARM::BI__builtin_neon_vshl_v:
  case ARM::BI__builtin_neon_vshlq_v:
    Int = usgn ? Intrinsic::arm_neon_vshiftu : Intrinsic::arm_neon_vshifts;
    return EmitNeonCall(CGM.getIntrinsic(Int, &Ty, 1), Ops, "vshl");
  case ARM::BI__builtin_neon_vshll_n_v:
    Int = usgn ? Intrinsic::arm_neon_vshiftlu : Intrinsic::arm_neon_vshiftls;
    return EmitNeonCall(CGM.getIntrinsic(Int, &Ty, 1), Ops, "vshll", 1);
  case ARM::BI__builtin_neon_vshl_n_v:
  case ARM::BI__builtin_neon_vshlq_n_v:
    Ops[1] = EmitNeonShiftVector(Ops[1], Ty, false);
    return Builder.CreateShl(Builder.CreateBitCast(Ops[0],Ty), Ops[1], "vshl_n");
  case ARM::BI__builtin_neon_vshrn_n_v:
    return EmitNeonCall(CGM.getIntrinsic(Intrinsic::arm_neon_vshiftn, &Ty, 1),
                        Ops, "vshrn_n", 1, true);
  case ARM::BI__builtin_neon_vshr_n_v:
  case ARM::BI__builtin_neon_vshrq_n_v:
    Ops[0] = Builder.CreateBitCast(Ops[0], Ty);
    Ops[1] = EmitNeonShiftVector(Ops[1], Ty, false);
    if (usgn)
      return Builder.CreateLShr(Ops[0], Ops[1], "vshr_n");
    else
      return Builder.CreateAShr(Ops[0], Ops[1], "vshr_n");
  case ARM::BI__builtin_neon_vsri_n_v:
  case ARM::BI__builtin_neon_vsriq_n_v:
    rightShift = true;
  case ARM::BI__builtin_neon_vsli_n_v:
  case ARM::BI__builtin_neon_vsliq_n_v:
    Ops[2] = EmitNeonShiftVector(Ops[2], Ty, rightShift);
    return EmitNeonCall(CGM.getIntrinsic(Intrinsic::arm_neon_vshiftins, &Ty, 1),
                        Ops, "vsli_n");
  case ARM::BI__builtin_neon_vsra_n_v:
  case ARM::BI__builtin_neon_vsraq_n_v:
    Ops[0] = Builder.CreateBitCast(Ops[0], Ty);
    Ops[1] = Builder.CreateBitCast(Ops[1], Ty);
    Ops[2] = EmitNeonShiftVector(Ops[2], Ty, false);
    if (usgn)
      Ops[1] = Builder.CreateLShr(Ops[1], Ops[2], "vsra_n");
    else
      Ops[1] = Builder.CreateAShr(Ops[1], Ops[2], "vsra_n");
    return Builder.CreateAdd(Ops[0], Ops[1]);
  case ARM::BI__builtin_neon_vst1_v:
  case ARM::BI__builtin_neon_vst1q_v:
    Ops.push_back(GetPointeeAlignment(*this, E->getArg(0)));
    return EmitNeonCall(CGM.getIntrinsic(Intrinsic::arm_neon_vst1, &Ty, 1),
                        Ops, "");
  case ARM::BI__builtin_neon_vst1_lane_v:
  case ARM::BI__builtin_neon_vst1q_lane_v:
    Ops[1] = Builder.CreateBitCast(Ops[1], Ty);
    Ops[1] = Builder.CreateExtractElement(Ops[1], Ops[2]);
    Ty = llvm::PointerType::getUnqual(Ops[1]->getType());
    return Builder.CreateStore(Ops[1], Builder.CreateBitCast(Ops[0], Ty));
  case ARM::BI__builtin_neon_vst2_v:
  case ARM::BI__builtin_neon_vst2q_v:
    Ops.push_back(GetPointeeAlignment(*this, E->getArg(0)));
    return EmitNeonCall(CGM.getIntrinsic(Intrinsic::arm_neon_vst2, &Ty, 1),
                        Ops, "");
  case ARM::BI__builtin_neon_vst2_lane_v:
  case ARM::BI__builtin_neon_vst2q_lane_v:
    Ops.push_back(GetPointeeAlignment(*this, E->getArg(0)));
    return EmitNeonCall(CGM.getIntrinsic(Intrinsic::arm_neon_vst2lane, &Ty, 1),
                        Ops, "");
  case ARM::BI__builtin_neon_vst3_v:
  case ARM::BI__builtin_neon_vst3q_v:
    Ops.push_back(GetPointeeAlignment(*this, E->getArg(0)));
    return EmitNeonCall(CGM.getIntrinsic(Intrinsic::arm_neon_vst3, &Ty, 1),
                        Ops, "");
  case ARM::BI__builtin_neon_vst3_lane_v:
  case ARM::BI__builtin_neon_vst3q_lane_v:
    Ops.push_back(GetPointeeAlignment(*this, E->getArg(0)));
    return EmitNeonCall(CGM.getIntrinsic(Intrinsic::arm_neon_vst3lane, &Ty, 1),
                        Ops, "");
  case ARM::BI__builtin_neon_vst4_v:
  case ARM::BI__builtin_neon_vst4q_v:
    Ops.push_back(GetPointeeAlignment(*this, E->getArg(0)));
    return EmitNeonCall(CGM.getIntrinsic(Intrinsic::arm_neon_vst4, &Ty, 1),
                        Ops, "");
  case ARM::BI__builtin_neon_vst4_lane_v:
  case ARM::BI__builtin_neon_vst4q_lane_v:
    Ops.push_back(GetPointeeAlignment(*this, E->getArg(0)));
    return EmitNeonCall(CGM.getIntrinsic(Intrinsic::arm_neon_vst4lane, &Ty, 1),
                        Ops, "");
  case ARM::BI__builtin_neon_vsubhn_v:
    return EmitNeonCall(CGM.getIntrinsic(Intrinsic::arm_neon_vsubhn, &Ty, 1),
                        Ops, "vsubhn");
  case ARM::BI__builtin_neon_vtbl1_v:
    return EmitNeonCall(CGM.getIntrinsic(Intrinsic::arm_neon_vtbl1),
                        Ops, "vtbl1");
  case ARM::BI__builtin_neon_vtbl2_v:
    return EmitNeonCall(CGM.getIntrinsic(Intrinsic::arm_neon_vtbl2),
                        Ops, "vtbl2");
  case ARM::BI__builtin_neon_vtbl3_v:
    return EmitNeonCall(CGM.getIntrinsic(Intrinsic::arm_neon_vtbl3),
                        Ops, "vtbl3");
  case ARM::BI__builtin_neon_vtbl4_v:
    return EmitNeonCall(CGM.getIntrinsic(Intrinsic::arm_neon_vtbl4),
                        Ops, "vtbl4");
  case ARM::BI__builtin_neon_vtbx1_v:
    return EmitNeonCall(CGM.getIntrinsic(Intrinsic::arm_neon_vtbx1),
                        Ops, "vtbx1");
  case ARM::BI__builtin_neon_vtbx2_v:
    return EmitNeonCall(CGM.getIntrinsic(Intrinsic::arm_neon_vtbx2),
                        Ops, "vtbx2");
  case ARM::BI__builtin_neon_vtbx3_v:
    return EmitNeonCall(CGM.getIntrinsic(Intrinsic::arm_neon_vtbx3),
                        Ops, "vtbx3");
  case ARM::BI__builtin_neon_vtbx4_v:
    return EmitNeonCall(CGM.getIntrinsic(Intrinsic::arm_neon_vtbx4),
                        Ops, "vtbx4");
  case ARM::BI__builtin_neon_vtst_v:
  case ARM::BI__builtin_neon_vtstq_v: {
    Ops[0] = Builder.CreateBitCast(Ops[0], Ty);
    Ops[1] = Builder.CreateBitCast(Ops[1], Ty);
    Ops[0] = Builder.CreateAnd(Ops[0], Ops[1]);
    Ops[0] = Builder.CreateICmp(ICmpInst::ICMP_NE, Ops[0],
                                ConstantAggregateZero::get(Ty));
    return Builder.CreateSExt(Ops[0], Ty, "vtst");
  }
  case ARM::BI__builtin_neon_vtrn_v:
  case ARM::BI__builtin_neon_vtrnq_v: {
    Ops[0] = Builder.CreateBitCast(Ops[0], llvm::PointerType::getUnqual(Ty));
    Ops[1] = Builder.CreateBitCast(Ops[1], Ty);
    Ops[2] = Builder.CreateBitCast(Ops[2], Ty);
    Value *SV;

    for (unsigned vi = 0; vi != 2; ++vi) {
      SmallVector<Constant*, 16> Indices;
      for (unsigned i = 0, e = VTy->getNumElements(); i != e; i += 2) {
        Indices.push_back(ConstantInt::get(Int32Ty, i+vi));
        Indices.push_back(ConstantInt::get(Int32Ty, i+e+vi));
      }
      Value *Addr = Builder.CreateConstInBoundsGEP1_32(Ops[0], vi);
      SV = llvm::ConstantVector::get(Indices.begin(), Indices.size());
      SV = Builder.CreateShuffleVector(Ops[1], Ops[2], SV, "vtrn");
      SV = Builder.CreateStore(SV, Addr);
    }
    return SV;
  }
  case ARM::BI__builtin_neon_vuzp_v:
  case ARM::BI__builtin_neon_vuzpq_v: {
    Ops[0] = Builder.CreateBitCast(Ops[0], llvm::PointerType::getUnqual(Ty));
    Ops[1] = Builder.CreateBitCast(Ops[1], Ty);
    Ops[2] = Builder.CreateBitCast(Ops[2], Ty);
    Value *SV;

    for (unsigned vi = 0; vi != 2; ++vi) {
      SmallVector<Constant*, 16> Indices;
      for (unsigned i = 0, e = VTy->getNumElements(); i != e; ++i)
        Indices.push_back(ConstantInt::get(Int32Ty, 2*i+vi));

      Value *Addr = Builder.CreateConstInBoundsGEP1_32(Ops[0], vi);
      SV = llvm::ConstantVector::get(Indices.begin(), Indices.size());
      SV = Builder.CreateShuffleVector(Ops[1], Ops[2], SV, "vuzp");
      SV = Builder.CreateStore(SV, Addr);
    }
    return SV;
  }
  case ARM::BI__builtin_neon_vzip_v:
  case ARM::BI__builtin_neon_vzipq_v: {
    Ops[0] = Builder.CreateBitCast(Ops[0], llvm::PointerType::getUnqual(Ty));
    Ops[1] = Builder.CreateBitCast(Ops[1], Ty);
    Ops[2] = Builder.CreateBitCast(Ops[2], Ty);
    Value *SV;

    for (unsigned vi = 0; vi != 2; ++vi) {
      SmallVector<Constant*, 16> Indices;
      for (unsigned i = 0, e = VTy->getNumElements(); i != e; i += 2) {
        Indices.push_back(ConstantInt::get(Int32Ty, (i + vi*e) >> 1));
        Indices.push_back(ConstantInt::get(Int32Ty, ((i + vi*e) >> 1)+e));
      }
      Value *Addr = Builder.CreateConstInBoundsGEP1_32(Ops[0], vi);
      SV = llvm::ConstantVector::get(Indices.begin(), Indices.size());
      SV = Builder.CreateShuffleVector(Ops[1], Ops[2], SV, "vzip");
      SV = Builder.CreateStore(SV, Addr);
    }
    return SV;
  }
  }
}

llvm::Value *CodeGenFunction::
BuildVector(const llvm::SmallVectorImpl<llvm::Value*> &Ops) {
  assert((Ops.size() & (Ops.size() - 1)) == 0 &&
         "Not a power-of-two sized vector!");
  bool AllConstants = true;
  for (unsigned i = 0, e = Ops.size(); i != e && AllConstants; ++i)
    AllConstants &= isa<Constant>(Ops[i]);

  // If this is a constant vector, create a ConstantVector.
  if (AllConstants) {
    std::vector<llvm::Constant*> CstOps;
    for (unsigned i = 0, e = Ops.size(); i != e; ++i)
      CstOps.push_back(cast<Constant>(Ops[i]));
    return llvm::ConstantVector::get(CstOps);
  }

  // Otherwise, insertelement the values to build the vector.
  Value *Result =
    llvm::UndefValue::get(llvm::VectorType::get(Ops[0]->getType(), Ops.size()));

  for (unsigned i = 0, e = Ops.size(); i != e; ++i)
    Result = Builder.CreateInsertElement(Result, Ops[i],
               llvm::ConstantInt::get(llvm::Type::getInt32Ty(VMContext), i));

  return Result;
}

Value *CodeGenFunction::EmitX86BuiltinExpr(unsigned BuiltinID,
                                           const CallExpr *E) {
  llvm::SmallVector<Value*, 4> Ops;

  // Find out if any arguments are required to be integer constant expressions.
  unsigned ICEArguments = 0;
  ASTContext::GetBuiltinTypeError Error;
  getContext().GetBuiltinType(BuiltinID, Error, &ICEArguments);
  assert(Error == ASTContext::GE_None && "Should not codegen an error");

  for (unsigned i = 0, e = E->getNumArgs(); i != e; i++) {
    // If this is a normal argument, just emit it as a scalar.
    if ((ICEArguments & (1 << i)) == 0) {
      Ops.push_back(EmitScalarExpr(E->getArg(i)));
      continue;
    }

    // If this is required to be a constant, constant fold it so that we know
    // that the generated intrinsic gets a ConstantInt.
    llvm::APSInt Result;
    bool IsConst = E->getArg(i)->isIntegerConstantExpr(Result, getContext());
    assert(IsConst && "Constant arg isn't actually constant?"); (void)IsConst;
    Ops.push_back(llvm::ConstantInt::get(VMContext, Result));
  }

  switch (BuiltinID) {
  default: return 0;
  case X86::BI__builtin_ia32_pslldi128:
  case X86::BI__builtin_ia32_psllqi128:
  case X86::BI__builtin_ia32_psllwi128:
  case X86::BI__builtin_ia32_psradi128:
  case X86::BI__builtin_ia32_psrawi128:
  case X86::BI__builtin_ia32_psrldi128:
  case X86::BI__builtin_ia32_psrlqi128:
  case X86::BI__builtin_ia32_psrlwi128: {
    Ops[1] = Builder.CreateZExt(Ops[1], Int64Ty, "zext");
    const llvm::Type *Ty = llvm::VectorType::get(Int64Ty, 2);
    llvm::Value *Zero = llvm::ConstantInt::get(Int32Ty, 0);
    Ops[1] = Builder.CreateInsertElement(llvm::UndefValue::get(Ty),
                                         Ops[1], Zero, "insert");
    Ops[1] = Builder.CreateBitCast(Ops[1], Ops[0]->getType(), "bitcast");
    const char *name = 0;
    Intrinsic::ID ID = Intrinsic::not_intrinsic;

    switch (BuiltinID) {
    default: assert(0 && "Unsupported shift intrinsic!");
    case X86::BI__builtin_ia32_pslldi128:
      name = "pslldi";
      ID = Intrinsic::x86_sse2_psll_d;
      break;
    case X86::BI__builtin_ia32_psllqi128:
      name = "psllqi";
      ID = Intrinsic::x86_sse2_psll_q;
      break;
    case X86::BI__builtin_ia32_psllwi128:
      name = "psllwi";
      ID = Intrinsic::x86_sse2_psll_w;
      break;
    case X86::BI__builtin_ia32_psradi128:
      name = "psradi";
      ID = Intrinsic::x86_sse2_psra_d;
      break;
    case X86::BI__builtin_ia32_psrawi128:
      name = "psrawi";
      ID = Intrinsic::x86_sse2_psra_w;
      break;
    case X86::BI__builtin_ia32_psrldi128:
      name = "psrldi";
      ID = Intrinsic::x86_sse2_psrl_d;
      break;
    case X86::BI__builtin_ia32_psrlqi128:
      name = "psrlqi";
      ID = Intrinsic::x86_sse2_psrl_q;
      break;
    case X86::BI__builtin_ia32_psrlwi128:
      name = "psrlwi";
      ID = Intrinsic::x86_sse2_psrl_w;
      break;
    }
    llvm::Function *F = CGM.getIntrinsic(ID);
    return Builder.CreateCall(F, &Ops[0], &Ops[0] + Ops.size(), name);
  }
  case X86::BI__builtin_ia32_vec_init_v8qi:
  case X86::BI__builtin_ia32_vec_init_v4hi:
  case X86::BI__builtin_ia32_vec_init_v2si:
    return Builder.CreateBitCast(BuildVector(Ops),
                                 llvm::Type::getX86_MMXTy(VMContext));
  case X86::BI__builtin_ia32_vec_ext_v2si:
    return Builder.CreateExtractElement(Ops[0],
                                  llvm::ConstantInt::get(Ops[1]->getType(), 0));
  case X86::BI__builtin_ia32_pslldi:
  case X86::BI__builtin_ia32_psllqi:
  case X86::BI__builtin_ia32_psllwi:
  case X86::BI__builtin_ia32_psradi:
  case X86::BI__builtin_ia32_psrawi:
  case X86::BI__builtin_ia32_psrldi:
  case X86::BI__builtin_ia32_psrlqi:
  case X86::BI__builtin_ia32_psrlwi: {
    Ops[1] = Builder.CreateZExt(Ops[1], Int64Ty, "zext");
    const llvm::Type *Ty = llvm::VectorType::get(Int64Ty, 1);
    Ops[1] = Builder.CreateBitCast(Ops[1], Ty, "bitcast");
    const char *name = 0;
    Intrinsic::ID ID = Intrinsic::not_intrinsic;

    switch (BuiltinID) {
    default: assert(0 && "Unsupported shift intrinsic!");
    case X86::BI__builtin_ia32_pslldi:
      name = "pslldi";
      ID = Intrinsic::x86_mmx_psll_d;
      break;
    case X86::BI__builtin_ia32_psllqi:
      name = "psllqi";
      ID = Intrinsic::x86_mmx_psll_q;
      break;
    case X86::BI__builtin_ia32_psllwi:
      name = "psllwi";
      ID = Intrinsic::x86_mmx_psll_w;
      break;
    case X86::BI__builtin_ia32_psradi:
      name = "psradi";
      ID = Intrinsic::x86_mmx_psra_d;
      break;
    case X86::BI__builtin_ia32_psrawi:
      name = "psrawi";
      ID = Intrinsic::x86_mmx_psra_w;
      break;
    case X86::BI__builtin_ia32_psrldi:
      name = "psrldi";
      ID = Intrinsic::x86_mmx_psrl_d;
      break;
    case X86::BI__builtin_ia32_psrlqi:
      name = "psrlqi";
      ID = Intrinsic::x86_mmx_psrl_q;
      break;
    case X86::BI__builtin_ia32_psrlwi:
      name = "psrlwi";
      ID = Intrinsic::x86_mmx_psrl_w;
      break;
    }
    llvm::Function *F = CGM.getIntrinsic(ID);
    return Builder.CreateCall(F, &Ops[0], &Ops[0] + Ops.size(), name);
  }
  case X86::BI__builtin_ia32_cmpps: {
    llvm::Function *F = CGM.getIntrinsic(Intrinsic::x86_sse_cmp_ps);
    return Builder.CreateCall(F, &Ops[0], &Ops[0] + Ops.size(), "cmpps");
  }
  case X86::BI__builtin_ia32_cmpss: {
    llvm::Function *F = CGM.getIntrinsic(Intrinsic::x86_sse_cmp_ss);
    return Builder.CreateCall(F, &Ops[0], &Ops[0] + Ops.size(), "cmpss");
  }
  case X86::BI__builtin_ia32_ldmxcsr: {
    const llvm::Type *PtrTy = llvm::Type::getInt8PtrTy(VMContext);
    Value *One = llvm::ConstantInt::get(Int32Ty, 1);
    Value *Tmp = Builder.CreateAlloca(Int32Ty, One, "tmp");
    Builder.CreateStore(Ops[0], Tmp);
    return Builder.CreateCall(CGM.getIntrinsic(Intrinsic::x86_sse_ldmxcsr),
                              Builder.CreateBitCast(Tmp, PtrTy));
  }
  case X86::BI__builtin_ia32_stmxcsr: {
    const llvm::Type *PtrTy = llvm::Type::getInt8PtrTy(VMContext);
    Value *One = llvm::ConstantInt::get(Int32Ty, 1);
    Value *Tmp = Builder.CreateAlloca(Int32Ty, One, "tmp");
    One = Builder.CreateCall(CGM.getIntrinsic(Intrinsic::x86_sse_stmxcsr),
                             Builder.CreateBitCast(Tmp, PtrTy));
    return Builder.CreateLoad(Tmp, "stmxcsr");
  }
  case X86::BI__builtin_ia32_cmppd: {
    llvm::Function *F = CGM.getIntrinsic(Intrinsic::x86_sse2_cmp_pd);
    return Builder.CreateCall(F, &Ops[0], &Ops[0] + Ops.size(), "cmppd");
  }
  case X86::BI__builtin_ia32_cmpsd: {
    llvm::Function *F = CGM.getIntrinsic(Intrinsic::x86_sse2_cmp_sd);
    return Builder.CreateCall(F, &Ops[0], &Ops[0] + Ops.size(), "cmpsd");
  }
  case X86::BI__builtin_ia32_storehps:
  case X86::BI__builtin_ia32_storelps: {
    llvm::Type *PtrTy = llvm::PointerType::getUnqual(Int64Ty);
    llvm::Type *VecTy = llvm::VectorType::get(Int64Ty, 2);

    // cast val v2i64
    Ops[1] = Builder.CreateBitCast(Ops[1], VecTy, "cast");

    // extract (0, 1)
    unsigned Index = BuiltinID == X86::BI__builtin_ia32_storelps ? 0 : 1;
    llvm::Value *Idx = llvm::ConstantInt::get(Int32Ty, Index);
    Ops[1] = Builder.CreateExtractElement(Ops[1], Idx, "extract");

    // cast pointer to i64 & store
    Ops[0] = Builder.CreateBitCast(Ops[0], PtrTy);
    return Builder.CreateStore(Ops[1], Ops[0]);
  }
  case X86::BI__builtin_ia32_palignr: {
    unsigned shiftVal = cast<llvm::ConstantInt>(Ops[2])->getZExtValue();

    // If palignr is shifting the pair of input vectors less than 9 bytes,
    // emit a shuffle instruction.
    if (shiftVal <= 8) {
      llvm::SmallVector<llvm::Constant*, 8> Indices;
      for (unsigned i = 0; i != 8; ++i)
        Indices.push_back(llvm::ConstantInt::get(Int32Ty, shiftVal + i));

      Value* SV = llvm::ConstantVector::get(Indices.begin(), Indices.size());
      return Builder.CreateShuffleVector(Ops[1], Ops[0], SV, "palignr");
    }

    // If palignr is shifting the pair of input vectors more than 8 but less
    // than 16 bytes, emit a logical right shift of the destination.
    if (shiftVal < 16) {
      // MMX has these as 1 x i64 vectors for some odd optimization reasons.
      const llvm::Type *VecTy = llvm::VectorType::get(Int64Ty, 1);

      Ops[0] = Builder.CreateBitCast(Ops[0], VecTy, "cast");
      Ops[1] = llvm::ConstantInt::get(VecTy, (shiftVal-8) * 8);

      // create i32 constant
      llvm::Function *F = CGM.getIntrinsic(Intrinsic::x86_mmx_psrl_q);
      return Builder.CreateCall(F, &Ops[0], &Ops[0] + 2, "palignr");
    }

    // If palignr is shifting the pair of vectors more than 32 bytes, emit zero.
    return llvm::Constant::getNullValue(ConvertType(E->getType()));
  }
  case X86::BI__builtin_ia32_palignr128: {
    unsigned shiftVal = cast<llvm::ConstantInt>(Ops[2])->getZExtValue();

    // If palignr is shifting the pair of input vectors less than 17 bytes,
    // emit a shuffle instruction.
    if (shiftVal <= 16) {
      llvm::SmallVector<llvm::Constant*, 16> Indices;
      for (unsigned i = 0; i != 16; ++i)
        Indices.push_back(llvm::ConstantInt::get(Int32Ty, shiftVal + i));

      Value* SV = llvm::ConstantVector::get(Indices.begin(), Indices.size());
      return Builder.CreateShuffleVector(Ops[1], Ops[0], SV, "palignr");
    }

    // If palignr is shifting the pair of input vectors more than 16 but less
    // than 32 bytes, emit a logical right shift of the destination.
    if (shiftVal < 32) {
      const llvm::Type *VecTy = llvm::VectorType::get(Int64Ty, 2);

      Ops[0] = Builder.CreateBitCast(Ops[0], VecTy, "cast");
      Ops[1] = llvm::ConstantInt::get(Int32Ty, (shiftVal-16) * 8);

      // create i32 constant
      llvm::Function *F = CGM.getIntrinsic(Intrinsic::x86_sse2_psrl_dq);
      return Builder.CreateCall(F, &Ops[0], &Ops[0] + 2, "palignr");
    }

    // If palignr is shifting the pair of vectors more than 32 bytes, emit zero.
    return llvm::Constant::getNullValue(ConvertType(E->getType()));
  }
  }
}

Value *CodeGenFunction::EmitPPCBuiltinExpr(unsigned BuiltinID,
                                           const CallExpr *E) {
  llvm::SmallVector<Value*, 4> Ops;

  for (unsigned i = 0, e = E->getNumArgs(); i != e; i++)
    Ops.push_back(EmitScalarExpr(E->getArg(i)));

  Intrinsic::ID ID = Intrinsic::not_intrinsic;

  switch (BuiltinID) {
  default: return 0;

  // vec_ld, vec_lvsl, vec_lvsr
  case PPC::BI__builtin_altivec_lvx:
  case PPC::BI__builtin_altivec_lvxl:
  case PPC::BI__builtin_altivec_lvebx:
  case PPC::BI__builtin_altivec_lvehx:
  case PPC::BI__builtin_altivec_lvewx:
  case PPC::BI__builtin_altivec_lvsl:
  case PPC::BI__builtin_altivec_lvsr:
  {
    Ops[1] = Builder.CreateBitCast(Ops[1], llvm::Type::getInt8PtrTy(VMContext));

    Ops[0] = Builder.CreateGEP(Ops[1], Ops[0], "tmp");
    Ops.pop_back();

    switch (BuiltinID) {
    default: assert(0 && "Unsupported ld/lvsl/lvsr intrinsic!");
    case PPC::BI__builtin_altivec_lvx:
      ID = Intrinsic::ppc_altivec_lvx;
      break;
    case PPC::BI__builtin_altivec_lvxl:
      ID = Intrinsic::ppc_altivec_lvxl;
      break;
    case PPC::BI__builtin_altivec_lvebx:
      ID = Intrinsic::ppc_altivec_lvebx;
      break;
    case PPC::BI__builtin_altivec_lvehx:
      ID = Intrinsic::ppc_altivec_lvehx;
      break;
    case PPC::BI__builtin_altivec_lvewx:
      ID = Intrinsic::ppc_altivec_lvewx;
      break;
    case PPC::BI__builtin_altivec_lvsl:
      ID = Intrinsic::ppc_altivec_lvsl;
      break;
    case PPC::BI__builtin_altivec_lvsr:
      ID = Intrinsic::ppc_altivec_lvsr;
      break;
    }
    llvm::Function *F = CGM.getIntrinsic(ID);
    return Builder.CreateCall(F, &Ops[0], &Ops[0] + Ops.size(), "");
  }

  // vec_st
  case PPC::BI__builtin_altivec_stvx:
  case PPC::BI__builtin_altivec_stvxl:
  case PPC::BI__builtin_altivec_stvebx:
  case PPC::BI__builtin_altivec_stvehx:
  case PPC::BI__builtin_altivec_stvewx:
  {
    Ops[2] = Builder.CreateBitCast(Ops[2], llvm::Type::getInt8PtrTy(VMContext));
    Ops[1] = Builder.CreateGEP(Ops[2], Ops[1], "tmp");
    Ops.pop_back();

    switch (BuiltinID) {
    default: assert(0 && "Unsupported st intrinsic!");
    case PPC::BI__builtin_altivec_stvx:
      ID = Intrinsic::ppc_altivec_stvx;
      break;
    case PPC::BI__builtin_altivec_stvxl:
      ID = Intrinsic::ppc_altivec_stvxl;
      break;
    case PPC::BI__builtin_altivec_stvebx:
      ID = Intrinsic::ppc_altivec_stvebx;
      break;
    case PPC::BI__builtin_altivec_stvehx:
      ID = Intrinsic::ppc_altivec_stvehx;
      break;
    case PPC::BI__builtin_altivec_stvewx:
      ID = Intrinsic::ppc_altivec_stvewx;
      break;
    }
    llvm::Function *F = CGM.getIntrinsic(ID);
    return Builder.CreateCall(F, &Ops[0], &Ops[0] + Ops.size(), "");
  }
  }
  return 0;
}