Revert "blockfreq: Rewrite BlockFrequencyInfoImpl"

This reverts commit r206704, as expected.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206707 91177308-0d34-0410-b5e6-96231b3b80d8

12 files changed, 316 insertions, 2930 deletions

diff --git a/include/llvm/Analysis/BlockFrequencyInfoImpl.h b/include/llvm/Analysis/BlockFrequencyInfoImpl.h
index 53a000d12f..f891afdf55 100644
--- a/include/llvm/Analysis/BlockFrequencyInfoImpl.h
+++ b/include/llvm/Analysis/BlockFrequencyInfoImpl.h
@@ -7,7 +7,7 @@
 //
 //===----------------------------------------------------------------------===//
 //
-// Shared implementation of BlockFrequency for IR and Machine Instructions.
+// Shared implementation of BlockFrequencyInfo for IR and Machine Instructions.
 //
 //===----------------------------------------------------------------------===//
 
@@ -16,6 +16,8 @@
 
 #include "llvm/ADT/DenseMap.h"
 #include "llvm/ADT/PostOrderIterator.h"
+#include "llvm/CodeGen/MachineBasicBlock.h"
+#include "llvm/CodeGen/MachineFunction.h"
 #include "llvm/IR/BasicBlock.h"
 #include "llvm/Support/BlockFrequency.h"
 #include "llvm/Support/BranchProbability.h"
@@ -24,1527 +26,374 @@
 #include <string>
 #include <vector>
 
-//===----------------------------------------------------------------------===//
-//
-// PositiveFloat definition.
-//
-// TODO: Make this private to BlockFrequencyInfoImpl or delete.
-//
-//===----------------------------------------------------------------------===//
 namespace llvm {
 
-class PositiveFloatBase {
-public:
-  static const int32_t MaxExponent = 16383;
-  static const int32_t MinExponent = -16382;
-  static const int DefaultPrecision = 10;
-
-  static void dump(uint64_t D, int16_t E, int Width);
-  static raw_ostream &print(raw_ostream &OS, uint64_t D, int16_t E, int Width,
-                            unsigned Precision);
-  static std::string toString(uint64_t D, int16_t E, int Width,
-                              unsigned Precision);
-  static int countLeadingZeros32(uint32_t N) { return countLeadingZeros(N); }
-  static int countLeadingZeros64(uint64_t N) { return countLeadingZeros(N); }
-  static uint64_t getHalf(uint64_t N) { return (N >> 1) + (N & 1); }
-
-  static std::pair<uint64_t, bool> splitSigned(int64_t N) {
-    if (N >= 0)
-      return std::make_pair(N, false);
-    uint64_t Unsigned = N == INT64_MIN ? UINT64_C(1) << 63 : uint64_t(-N);
-    return std::make_pair(Unsigned, true);
-  }
-  static int64_t joinSigned(uint64_t U, bool IsNeg) {
-    if (U > uint64_t(INT64_MAX))
-      return IsNeg ? INT64_MIN : INT64_MAX;
-    return IsNeg ? -int64_t(U) : int64_t(U);
-  }
-
-  static int32_t extractLg(const std::pair<int32_t, int> &Lg) {
-    return Lg.first;
-  }
-  static int32_t extractLgFloor(const std::pair<int32_t, int> &Lg) {
-    return Lg.first - (Lg.second > 0);
-  }
-  static int32_t extractLgCeiling(const std::pair<int32_t, int> &Lg) {
-    return Lg.first + (Lg.second < 0);
-  }
-
-  static std::pair<uint64_t, int16_t> divide64(uint64_t L, uint64_t R);
-  static std::pair<uint64_t, int16_t> multiply64(uint64_t L, uint64_t R);
-
-  static int compare(uint64_t L, uint64_t R, int Shift) {
-    assert(Shift >= 0);
-    assert(Shift < 64);
 
-    uint64_t L_adjusted = L >> Shift;
-    if (L_adjusted < R)
-      return -1;
-    if (L_adjusted > R)
-      return 1;
+class BranchProbabilityInfo;
+class BlockFrequencyInfo;
+class MachineBranchProbabilityInfo;
+class MachineBlockFrequencyInfo;
 
-    return L > L_adjusted << Shift ? 1 : 0;
-  }
+namespace bfi_detail {
+template <class BlockT> struct TypeMap {};
+template <> struct TypeMap<BasicBlock> {
+  typedef BasicBlock BlockT;
+  typedef Function FunctionT;
+  typedef BranchProbabilityInfo BranchProbabilityInfoT;
 };
-
-/// \brief Simple representation of a positive floating point.
-///
-/// PositiveFloat is a positive floating point number.  It uses simple
-/// saturation arithmetic, and every operation is well-defined for every value.
-///
-/// The number is split into a signed exponent and unsigned digits.  The number
-/// represented is \c getDigits()*2^getExponent().  In this way, the digits are
-/// much like the mantissa in the x87 long double, but there is no canonical
-/// form, so the same number can be represented by many bit representations
-/// (it's always in "denormal" mode).
-///
-/// PositiveFloat is templated on the underlying integer type for digits, which
-/// is expected to be one of uint64_t, uint32_t, uint16_t or uint8_t.
-///
-/// Unlike builtin floating point types, PositiveFloat is portable.
-///
-/// Unlike APFloat, PositiveFloat does not model architecture floating point
-/// behaviour (this should make it a little faster), and implements most
-/// operators (this makes it usable).
-///
-/// PositiveFloat is totally ordered.  However, there is no canonical form, so
-/// there are multiple representations of most scalars.  E.g.:
-///
-///     PositiveFloat(8u, 0) == PositiveFloat(4u, 1)
-///     PositiveFloat(4u, 1) == PositiveFloat(2u, 2)
-///     PositiveFloat(2u, 2) == PositiveFloat(1u, 3)
-///
-/// PositiveFloat implements most arithmetic operations.  Precision is kept
-/// where possible.  Uses simple saturation arithmetic, so that operations
-/// saturate to 0.0 or getLargest() rather than under or overflowing.  It has
-/// some extra arithmetic for unit inversion.  0.0/0.0 is defined to be 0.0.
-/// Any other division by 0.0 is defined to be getLargest().
-///
-/// As a convenience for modifying the exponent, left and right shifting are
-/// both implemented, and both interpret negative shifts as positive shifts in
-/// the opposite direction.
-///
-/// Future work might extract most of the implementation into a base class
-/// (e.g., \c Float) that has an \c IsSigned template parameter.  The initial
-/// use case for this only needed positive semantics, but it wouldn't take much
-/// work to extend.
-///
-/// Exponents are limited to the range accepted by x87 long double.  This makes
-/// it trivial to add functionality to convert to APFloat (this is already
-/// relied on for the implementation of printing).
-template <class DigitsT> class PositiveFloat : PositiveFloatBase {
-public:
-  static_assert(!std::numeric_limits<DigitsT>::is_signed,
-                "only unsigned floats supported");
-
-  typedef DigitsT DigitsType;
-
-private:
-  typedef std::numeric_limits<DigitsType> DigitsLimits;
-
-  static const int Width = sizeof(DigitsType) * 8;
-  static_assert(Width <= 64, "invalid integer width for digits");
-
-private:
-  DigitsType Digits;
-  int16_t Exponent;
-
-public:
-  PositiveFloat() : Digits(0), Exponent(0) {}
-
-  PositiveFloat(DigitsType Digits, int16_t Exponent)
-      : Digits(Digits), Exponent(Exponent) {}
-
-private:
-  PositiveFloat(const std::pair<uint64_t, int16_t> &X)
-      : Digits(X.first), Exponent(X.second) {}
-
-public:
-  static PositiveFloat getZero() { return PositiveFloat(0, 0); }
-  static PositiveFloat getOne() { return PositiveFloat(1, 0); }
-  static PositiveFloat getLargest() {
-    return PositiveFloat(DigitsLimits::max(), MaxExponent);
-  }
-  static PositiveFloat getFloat(uint64_t N) { return adjustToWidth(N, 0); }
-  static PositiveFloat getInverseFloat(uint64_t N) {
-    return getFloat(N).invert();
-  }
-  static PositiveFloat getFraction(DigitsType N, DigitsType D) {
-    return getQuotient(N, D);
-  }
-
-  int16_t getExponent() const { return Exponent; }
-  DigitsType getDigits() const { return Digits; }
-
-  /// \brief Convert to the given integer type.
-  ///
-  /// Convert to \c IntT using simple saturating arithmetic, truncating if
-  /// necessary.
-  template <class IntT> IntT toInt() const;
-
-  bool isZero() const { return !Digits; }
-  bool isLargest() const { return *this == getLargest(); }
-  bool isOne() const {
-    if (Exponent > 0 || Exponent <= -Width)
-      return false;
-    return Digits == DigitsType(1) << -Exponent;
-  }
-
-  /// \brief The log base 2, rounded.
-  ///
-  /// Get the lg of the scalar.  lg 0 is defined to be INT32_MIN.
-  int32_t lg() const { return extractLg(lgImpl()); }
-
-  /// \brief The log base 2, rounded towards INT32_MIN.
-  ///
-  /// Get the lg floor.  lg 0 is defined to be INT32_MIN.
-  int32_t lgFloor() const { return extractLgFloor(lgImpl()); }
-
-  /// \brief The log base 2, rounded towards INT32_MAX.
-  ///
-  /// Get the lg ceiling.  lg 0 is defined to be INT32_MIN.
-  int32_t lgCeiling() const { return extractLgCeiling(lgImpl()); }
-
-  bool operator==(const PositiveFloat &X) const { return compare(X) == 0; }
-  bool operator<(const PositiveFloat &X) const { return compare(X) < 0; }
-  bool operator!=(const PositiveFloat &X) const { return compare(X) != 0; }
-  bool operator>(const PositiveFloat &X) const { return compare(X) > 0; }
-  bool operator<=(const PositiveFloat &X) const { return compare(X) <= 0; }
-  bool operator>=(const PositiveFloat &X) const { return compare(X) >= 0; }
-
-  bool operator!() const { return isZero(); }
-
-  /// \brief Convert to a decimal representation in a string.
-  ///
-  /// Convert to a string.  Uses scientific notation for very large/small
-  /// numbers.  Scientific notation is used roughly for numbers outside of the
-  /// range 2^-64 through 2^64.
-  ///
-  /// \c Precision indicates the number of decimal digits of precision to use;
-  /// 0 requests the maximum available.
-  ///
-  /// As a special case to make debugging easier, if the number is small enough
-  /// to convert without scientific notation and has more than \c Precision
-  /// digits before the decimal place, it's printed accurately to the first
-  /// digit past zero.  E.g., assuming 10 digits of precision:
-  ///
-  ///     98765432198.7654... => 98765432198.8
-  ///      8765432198.7654... =>  8765432198.8
-  ///       765432198.7654... =>   765432198.8
-  ///        65432198.7654... =>    65432198.77
-  ///         5432198.7654... =>     5432198.765
-  std::string toString(unsigned Precision = DefaultPrecision) {
-    return PositiveFloatBase::toString(Digits, Exponent, Width, Precision);
-  }
-
-  /// \brief Print a decimal representation.
-  ///
-  /// Print a string.  See toString for documentation.
-  raw_ostream &print(raw_ostream &OS,
-                     unsigned Precision = DefaultPrecision) const {
-    return PositiveFloatBase::print(OS, Digits, Exponent, Width, Precision);
-  }
-  void dump() const { return PositiveFloatBase::dump(Digits, Exponent, Width); }
-
-  PositiveFloat &operator+=(const PositiveFloat &X);
-  PositiveFloat &operator-=(const PositiveFloat &X);
-  PositiveFloat &operator*=(const PositiveFloat &X);
-  PositiveFloat &operator/=(const PositiveFloat &X);
-  PositiveFloat &operator<<=(int16_t Shift) { shiftLeft(Shift); return *this; }
-  PositiveFloat &operator>>=(int16_t Shift) { shiftRight(Shift); return *this; }
-
-private:
-  void shiftLeft(int32_t Shift);
-  void shiftRight(int32_t Shift);
-
-  /// \brief Adjust two floats to have matching exponents.
-  ///
-  /// Adjust \c this and \c X to have matching exponents.  Returns the new \c X
-  /// by value.  Does nothing if \a isZero() for either.
-  ///
-  /// The value that compares smaller will lose precision, and possibly become
-  /// \a isZero().
-  PositiveFloat matchExponents(PositiveFloat X);
-
-  /// \brief Increase exponent to match another float.
-  ///
-  /// Increases \c this to have an exponent matching \c X.  May decrease the
-  /// exponent of \c X in the process, and \c this may possibly become \a
-  /// isZero().
-  void increaseExponentToMatch(PositiveFloat &X, int32_t ExponentDiff);
-
-public:
-  /// \brief Scale a large number accurately.
-  ///
-  /// Scale N (multiply it by this).  Uses full precision multiplication, even
-  /// if Width is smaller than 64, so information is not lost.
-  uint64_t scale(uint64_t N) const;
-  uint64_t scaleByInverse(uint64_t N) const {
-    // TODO: implement directly, rather than relying on inverse.  Inverse is
-    // expensive.
-    return inverse().scale(N);
-  }
-  int64_t scale(int64_t N) const {
-    std::pair<uint64_t, bool> Unsigned = splitSigned(N);
-    return joinSigned(scale(Unsigned.first), Unsigned.second);
-  }
-  int64_t scaleByInverse(int64_t N) const {
-    std::pair<uint64_t, bool> Unsigned = splitSigned(N);
-    return joinSigned(scaleByInverse(Unsigned.first), Unsigned.second);
-  }
-
-  int compare(const PositiveFloat &X) const;
-  int compareTo(uint64_t N) const {
-    PositiveFloat Float = getFloat(N);
-    int Compare = compare(Float);
-    if (Width == 64 || Compare != 0)
-      return Compare;
-
-    // Check for precision loss.  We know *this == RoundTrip.
-    uint64_t RoundTrip = Float.template toInt<uint64_t>();
-    return N == RoundTrip ? 0 : RoundTrip < N ? -1 : 1;
-  }
-  int compareTo(int64_t N) const { return N < 0 ? 1 : compareTo(uint64_t(N)); }
-
-  PositiveFloat &invert() { return *this = PositiveFloat::getFloat(1) / *this; }
-  PositiveFloat inverse() const { return PositiveFloat(*this).invert(); }
-
-private:
-  static PositiveFloat getProduct(DigitsType L, DigitsType R);
-  static PositiveFloat getQuotient(DigitsType Dividend, DigitsType Divisor);
-
-  std::pair<int32_t, int> lgImpl() const;
-  static int countLeadingZerosWidth(DigitsType Digits) {
-    if (Width == 64)
-      return countLeadingZeros64(Digits);
-    if (Width == 32)
-      return countLeadingZeros32(Digits);
-    return countLeadingZeros32(Digits) + Width - 32;
-  }
-
-  static PositiveFloat adjustToWidth(uint64_t N, int32_t S) {
-    assert(S >= MinExponent);
-    assert(S <= MaxExponent);
-    if (Width == 64 || N <= DigitsLimits::max())
-      return PositiveFloat(N, S);
-
-    // Shift right.
-    int Shift = 64 - Width - countLeadingZeros64(N);
-    DigitsType Shifted = N >> Shift;
-
-    // Round.
-    assert(S + Shift <= MaxExponent);
-    return getRounded(PositiveFloat(Shifted, S + Shift),
-                      N & UINT64_C(1) << (Shift - 1));
-  }
-
-  static PositiveFloat getRounded(PositiveFloat P, bool Round) {
-    if (!Round)
-      return P;
-    if (P.Digits == DigitsLimits::max())
-      // Careful of overflow in the exponent.
-      return PositiveFloat(1, P.Exponent) <<= Width;
-    return PositiveFloat(P.Digits + 1, P.Exponent);
-  }
+template <> struct TypeMap<MachineBasicBlock> {
+  typedef MachineBasicBlock BlockT;
+  typedef MachineFunction FunctionT;
+  typedef MachineBranchProbabilityInfo BranchProbabilityInfoT;
 };
-
-#define POSITIVE_FLOAT_BOP(op, base)                                           \
-  template <class DigitsT>                                                     \
-  PositiveFloat<DigitsT> operator op(const PositiveFloat<DigitsT> &L,          \
-                                     const PositiveFloat<DigitsT> &R) {        \
-    return PositiveFloat<DigitsT>(L) base R;                                   \
-  }
-POSITIVE_FLOAT_BOP(+, += )
-POSITIVE_FLOAT_BOP(-, -= )
-POSITIVE_FLOAT_BOP(*, *= )
-POSITIVE_FLOAT_BOP(/, /= )
-POSITIVE_FLOAT_BOP(<<, <<= )
-POSITIVE_FLOAT_BOP(>>, >>= )
-#undef POSITIVE_FLOAT_BOP
-
-template <class DigitsT>
-raw_ostream &operator<<(raw_ostream &OS, const PositiveFloat<DigitsT> &X) {
-  return X.print(OS, 10);
-}
-
-#define POSITIVE_FLOAT_COMPARE_TO_TYPE(op, T1, T2)                             \
-  template <class DigitsT>                                                     \
-  bool operator op(const PositiveFloat<DigitsT> &L, T1 R) {                    \
-    return L.compareTo(T2(R)) op 0;                                            \
-  }                                                                            \
-  template <class DigitsT>                                                     \
-  bool operator op(T1 L, const PositiveFloat<DigitsT> &R) {                    \
-    return 0 op R.compareTo(T2(L));                                            \
-  }
-#define POSITIVE_FLOAT_COMPARE_TO(op)                                          \
-  POSITIVE_FLOAT_COMPARE_TO_TYPE(op, uint64_t, uint64_t)                       \
-  POSITIVE_FLOAT_COMPARE_TO_TYPE(op, uint32_t, uint64_t)                       \
-  POSITIVE_FLOAT_COMPARE_TO_TYPE(op, int64_t, int64_t)                         \
-  POSITIVE_FLOAT_COMPARE_TO_TYPE(op, int32_t, int64_t)
-POSITIVE_FLOAT_COMPARE_TO(< )
-POSITIVE_FLOAT_COMPARE_TO(> )
-POSITIVE_FLOAT_COMPARE_TO(== )
-POSITIVE_FLOAT_COMPARE_TO(!= )
-POSITIVE_FLOAT_COMPARE_TO(<= )
-POSITIVE_FLOAT_COMPARE_TO(>= )
-#undef POSITIVE_FLOAT_COMPARE_TO
-#undef POSITIVE_FLOAT_COMPARE_TO_TYPE
-
-template <class DigitsT>
-uint64_t PositiveFloat<DigitsT>::scale(uint64_t N) const {
-  if (Width == 64 || N <= DigitsLimits::max())
-    return (getFloat(N) * *this).template toInt<uint64_t>();
-
-  // Defer to the 64-bit version.
-  return PositiveFloat<uint64_t>(Digits, Exponent).scale(N);
-}
-
-template <class DigitsT>
-PositiveFloat<DigitsT> PositiveFloat<DigitsT>::getProduct(DigitsType L,
-                                                          DigitsType R) {
-  // Check for zero.
-  if (!L || !R)
-    return getZero();
-
-  // Check for numbers that we can compute with 64-bit math.
-  if (Width <= 32 || (L <= UINT32_MAX && R <= UINT32_MAX))
-    return adjustToWidth(uint64_t(L) * uint64_t(R), 0);
-
-  // Do the full thing.
-  return PositiveFloat(multiply64(L, R));
-}
-template <class DigitsT>
-PositiveFloat<DigitsT> PositiveFloat<DigitsT>::getQuotient(DigitsType Dividend,
-                                                           DigitsType Divisor) {
-  // Check for zero.
-  if (!Dividend)
-    return getZero();
-  if (!Divisor)
-    return getLargest();
-
-  if (Width == 64)
-    return PositiveFloat(divide64(Dividend, Divisor));
-
-  // We can compute this with 64-bit math.
-  int Shift = countLeadingZeros64(Dividend);
-  uint64_t Shifted = uint64_t(Dividend) << Shift;
-  uint64_t Quotient = Shifted / Divisor;
-
-  // If Quotient needs to be shifted, then adjustToWidth will round.
-  if (Quotient > DigitsLimits::max())
-    return adjustToWidth(Quotient, -Shift);
-
-  // Round based on the value of the next bit.
-  return getRounded(PositiveFloat(Quotient, -Shift),
-                    Shifted % Divisor >= getHalf(Divisor));
-}
-
-template <class DigitsT>
-template <class IntT>
-IntT PositiveFloat<DigitsT>::toInt() const {
-  typedef std::numeric_limits<IntT> Limits;
-  if (*this < 1)
-    return 0;
-  if (*this >= Limits::max())
-    return Limits::max();
-
-  IntT N = Digits;
-  if (Exponent > 0) {
-    assert(size_t(Exponent) < sizeof(IntT) * 8);
-    return N << Exponent;
-  }
-  if (Exponent < 0) {
-    assert(size_t(-Exponent) < sizeof(IntT) * 8);
-    return N >> -Exponent;
-  }
-  return N;
 }
 
-template <class DigitsT>
-std::pair<int32_t, int> PositiveFloat<DigitsT>::lgImpl() const {
-  if (isZero())
-    return std::make_pair(INT32_MIN, 0);
+/// BlockFrequencyInfoImpl implements block frequency algorithm for IR and
+/// Machine Instructions. Algorithm starts with value ENTRY_FREQ
+/// for the entry block and then propagates frequencies using branch weights
+/// from (Machine)BranchProbabilityInfo. LoopInfo is not required because
+/// algorithm can find "backedges" by itself.
+template <class BT>
+class BlockFrequencyInfoImpl {
+  typedef typename bfi_detail::TypeMap<BT>::BlockT BlockT;
+  typedef typename bfi_detail::TypeMap<BT>::FunctionT FunctionT;
+  typedef typename bfi_detail::TypeMap<BT>::BranchProbabilityInfoT
+  BranchProbabilityInfoT;
 
-  // Get the floor of the lg of Digits.
-  int32_t LocalFloor = Width - countLeadingZerosWidth(Digits) - 1;
+  DenseMap<const BlockT *, BlockFrequency> Freqs;
 
-  // Get the floor of the lg of this.
-  int32_t Floor = Exponent + LocalFloor;
-  if (Digits == UINT64_C(1) << LocalFloor)
-    return std::make_pair(Floor, 0);
+  BranchProbabilityInfoT *BPI;
 
-  // Round based on the next digit.
-  assert(LocalFloor >= 1);
-  bool Round = Digits & UINT64_C(1) << (LocalFloor - 1);
-  return std::make_pair(Floor + Round, Round ? 1 : -1);
-}
+  FunctionT *Fn;
 
-template <class DigitsT>
-PositiveFloat<DigitsT> PositiveFloat<DigitsT>::matchExponents(PositiveFloat X) {
-  if (isZero() || X.isZero() || Exponent == X.Exponent)
-    return X;
-
-  int32_t Diff = int32_t(X.Exponent) - int32_t(Exponent);
-  if (Diff > 0)
-    increaseExponentToMatch(X, Diff);
-  else
-    X.increaseExponentToMatch(*this, -Diff);
-  return X;
-}
-template <class DigitsT>
-void PositiveFloat<DigitsT>::increaseExponentToMatch(PositiveFloat &X,
-                                                     int32_t ExponentDiff) {
-  assert(ExponentDiff > 0);
-  if (ExponentDiff >= 2 * Width) {
-    *this = getZero();
-    return;
-  }
+  typedef GraphTraits< Inverse<BlockT *> > GT;
 
-  // Use up any leading zeros on X, and then shift this.
-  int32_t ShiftX = std::min(countLeadingZerosWidth(X.Digits), ExponentDiff);
-  assert(ShiftX < Width);
+  static const uint64_t EntryFreq = 1 << 14;
 
-  int32_t ShiftThis = ExponentDiff - ShiftX;
-  if (ShiftThis >= Width) {
-    *this = getZero();
-    return;
+  std::string getBlockName(BasicBlock *BB) const {
+    return BB->getName().str();
   }
 
-  X.Digits <<= ShiftX;
-  X.Exponent -= ShiftX;
-  Digits >>= ShiftThis;
-  Exponent += ShiftThis;
-  return;
-}
+  std::string getBlockName(MachineBasicBlock *MBB) const {
+    std::string str;
+    raw_string_ostream ss(str);
+    ss << "BB#" << MBB->getNumber();
 
-template <class DigitsT>
-PositiveFloat<DigitsT> &PositiveFloat<DigitsT>::
-operator+=(const PositiveFloat &X) {
-  if (isLargest() || X.isZero())
-    return *this;
-  if (isZero() || X.isLargest())
-    return *this = X;
-
-  // Normalize exponents.
-  PositiveFloat Scaled = matchExponents(X);
-
-  // Check for zero again.
-  if (isZero())
-    return *this = Scaled;
-  if (Scaled.isZero())
-    return *this;
-
-  // Compute sum.
-  DigitsType Sum = Digits + Scaled.Digits;
-  bool DidOverflow = Sum < Digits;
-  Digits = Sum;
-  if (!DidOverflow)
-    return *this;
-
-  if (Exponent == MaxExponent)
-    return *this = getLargest();
-
-  ++Exponent;
-  Digits = UINT64_C(1) << (Width - 1) | Digits >> 1;
-
-  return *this;
-}
-template <class DigitsT>
-PositiveFloat<DigitsT> &PositiveFloat<DigitsT>::
-operator-=(const PositiveFloat &X) {
-  if (X.isZero())
-    return *this;
-  if (*this <= X)
-    return *this = getZero();
-
-  // Normalize exponents.
-  PositiveFloat Scaled = matchExponents(X);
-  assert(Digits >= Scaled.Digits);
-
-  // Compute difference.
-  if (!Scaled.isZero()) {
-    Digits -= Scaled.Digits;
-    return *this;
-  }
+    if (const BasicBlock *BB = MBB->getBasicBlock())
+      ss << " derived from LLVM BB " << BB->getName();
 
-  // Check if X just barely lost its last bit.  E.g., for 32-bit:
-  //
-  //   1*2^32 - 1*2^0 == 0xffffffff != 1*2^32
-  if (*this == PositiveFloat(1, X.lgFloor() + Width)) {
-    Digits = DigitsType(0) - 1;
-    --Exponent;
-  }
-  return *this;
-}
-template <class DigitsT>
-PositiveFloat<DigitsT> &PositiveFloat<DigitsT>::
-operator*=(const PositiveFloat &X) {
-  if (isZero())
-    return *this;
-  if (X.isZero())
-    return *this = X;
-
-  // Save the exponents.
-  int32_t Exponents = int32_t(Exponent) + int32_t(X.Exponent);
-
-  // Get the raw product.
-  *this = getProduct(Digits, X.Digits);
-
-  // Combine with exponents.
-  return *this <<= Exponents;
-}
-template <class DigitsT>
-PositiveFloat<DigitsT> &PositiveFloat<DigitsT>::
-operator/=(const PositiveFloat &X) {
-  if (isZero())
-    return *this;
-  if (X.isZero())
-    return *this = getLargest();
-
-  // Save the exponents.
-  int32_t Exponents = int32_t(Exponent) - int32_t(X.Exponent);
-
-  // Get the raw quotient.
-  *this = getQuotient(Digits, X.Digits);
-
-  // Combine with exponents.
-  return *this <<= Exponents;
-}
-template <class DigitsT>
-void PositiveFloat<DigitsT>::shiftLeft(int32_t Shift) {
-  if (!Shift || isZero())
-    return;
-  assert(Shift != INT32_MIN);
-  if (Shift < 0) {
-    shiftRight(-Shift);
-    return;
+    return ss.str();
   }
 
-  // Shift as much as we can in the exponent.
-  int32_t ExponentShift = std::min(Shift, MaxExponent - Exponent);
-  Exponent += ExponentShift;
-  if (ExponentShift == Shift)
-    return;
-
-  // Check this late, since it's rare.
-  if (isLargest())
-    return;
-
-  // Shift the digits themselves.
-  Shift -= ExponentShift;
-  if (Shift > countLeadingZerosWidth(Digits)) {
-    // Saturate.
-    *this = getLargest();
-    return;
+  void setBlockFreq(BlockT *BB, BlockFrequency Freq) {
+    Freqs[BB] = Freq;
+    DEBUG(dbgs() << "Frequency(" << getBlockName(BB) << ") = ";
+          printBlockFreq(dbgs(), Freq) << "\n");
   }
 
-  Digits <<= Shift;
-  return;
-}
-
-template <class DigitsT>
-void PositiveFloat<DigitsT>::shiftRight(int32_t Shift) {
-  if (!Shift || isZero())
-    return;
-  assert(Shift != INT32_MIN);
-  if (Shift < 0) {
-    shiftLeft(-Shift);
-    return;
+  /// getEdgeFreq - Return edge frequency based on SRC frequency and Src -> Dst
+  /// edge probability.
+  BlockFrequency getEdgeFreq(BlockT *Src, BlockT *Dst) const {
+    BranchProbability Prob = BPI->getEdgeProbability(Src, Dst);
+    return getBlockFreq(Src) * Prob;
   }
 
-  // Shift as much as we can in the exponent.
-  int32_t ExponentShift = std::min(Shift, Exponent - MinExponent);
-  Exponent -= ExponentShift;
-  if (ExponentShift == Shift)
-    return;
-
-  // Shift the digits themselves.
-  Shift -= ExponentShift;
-  if (Shift >= Width) {
-    // Saturate.
-    *this = getZero();
-    return;
+  /// incBlockFreq - Increase BB block frequency by FREQ.
+  ///
+  void incBlockFreq(BlockT *BB, BlockFrequency Freq) {
+    Freqs[BB] += Freq;
+    DEBUG(dbgs() << "Frequency(" << getBlockName(BB) << ") += ";
+          printBlockFreq(dbgs(), Freq) << " --> ";
+          printBlockFreq(dbgs(), Freqs[BB]) << "\n");
   }
 
-  Digits >>= Shift;
-  return;
-}
+  // All blocks in postorder.
+  std::vector<BlockT *> POT;
 
-template <class DigitsT>
-int PositiveFloat<DigitsT>::compare(const PositiveFloat &X) const {
-  // Check for zero.
-  if (isZero())
-    return X.isZero() ? 0 : -1;
-  if (X.isZero())
-    return 1;
-
-  // Check for the scale.  Use lgFloor to be sure that the exponent difference
-  // is always lower than 64.
-  int32_t lgL = lgFloor(), lgR = X.lgFloor();
-  if (lgL != lgR)
-    return lgL < lgR ? -1 : 1;
-
-  // Compare digits.
-  if (Exponent < X.Exponent)
-    return PositiveFloatBase::compare(Digits, X.Digits, X.Exponent - Exponent);
-
-  return -PositiveFloatBase::compare(X.Digits, Digits, Exponent - X.Exponent);
-}
+  // Map Block -> Position in reverse-postorder list.
+  DenseMap<BlockT *, unsigned> RPO;
 
-template <class T> struct isPodLike<PositiveFloat<T>> {
-  static const bool value = true;
-};
-}
+  // For each loop header, record the per-iteration probability of exiting the
+  // loop. This is the reciprocal of the expected number of loop iterations.
+  typedef DenseMap<BlockT*, BranchProbability> LoopExitProbMap;
+  LoopExitProbMap LoopExitProb;
 
-//===----------------------------------------------------------------------===//
-//
-// BlockMass definition.
-//
-// TODO: Make this private to BlockFrequencyInfoImpl or delete.
-//
-//===----------------------------------------------------------------------===//
-namespace llvm {
-
-/// \brief Mass of a block.
-///
-/// This class implements a sort of fixed-point fraction always between 0.0 and
-/// 1.0.  getMass() == UINT64_MAX indicates a value of 1.0.
-///
-/// Masses can be added and subtracted.  Simple saturation arithmetic is used,
-/// so arithmetic operations never overflow or underflow.
-///
-/// Masses can be multiplied.  Multiplication treats full mass as 1.0 and uses
-/// an inexpensive floating-point algorithm that's off-by-one (almost, but not
-/// quite, maximum precision).
-///
-/// Masses can be scaled by \a BranchProbability at maximum precision.
-class BlockMass {
-  uint64_t Mass;
-
-public:
-  BlockMass() : Mass(0) {}
-  explicit BlockMass(uint64_t Mass) : Mass(Mass) {}
-
-  static BlockMass getEmpty() { return BlockMass(); }
-  static BlockMass getFull() { return BlockMass(UINT64_MAX); }
+  // (reverse-)postorder traversal iterators.
+  typedef typename std::vector<BlockT *>::iterator pot_iterator;
+  typedef typename std::vector<BlockT *>::reverse_iterator rpot_iterator;
 
-  uint64_t getMass() const { return Mass; }
+  pot_iterator pot_begin() { return POT.begin(); }
+  pot_iterator pot_end() { return POT.end(); }
 
-  bool isFull() const { return Mass == UINT64_MAX; }
-  bool isEmpty() const { return !Mass; }
+  rpot_iterator rpot_begin() { return POT.rbegin(); }
+  rpot_iterator rpot_end() { return POT.rend(); }
 
-  bool operator!() const { return isEmpty(); }
+  rpot_iterator rpot_at(BlockT *BB) {
+    rpot_iterator I = rpot_begin();
+    unsigned idx = RPO.lookup(BB);
+    assert(idx);
+    std::advance(I, idx - 1);
 
-  /// \brief Add another mass.
-  ///
-  /// Adds another mass, saturating at \a isFull() rather than overflowing.
-  BlockMass &operator+=(const BlockMass &X) {
-    uint64_t Sum = Mass + X.Mass;
-    Mass = Sum < Mass ? UINT64_MAX : Sum;
-    return *this;
+    assert(*I == BB);
+    return I;
   }
 
-  /// \brief Subtract another mass.
+  /// isBackedge - Return if edge Src -> Dst is a reachable backedge.
   ///
-  /// Subtracts another mass, saturating at \a isEmpty() rather than
-  /// undeflowing.
-  BlockMass &operator-=(const BlockMass &X) {
-    uint64_t Diff = Mass - X.Mass;
-    Mass = Diff > Mass ? 0 : Diff;
-    return *this;
-  }
-
-  /// \brief Scale by another mass.
-  ///
-  /// The current implementation is a little imprecise, but it's relatively
-  /// fast, never overflows, and maintains the property that 1.0*1.0==1.0
-  /// (where isFull represents the number 1.0).  It's an approximation of
-  /// 128-bit multiply that gets right-shifted by 64-bits.
-  ///
-  /// For a given digit size, multiplying two-digit numbers looks like:
-  ///
-  ///                  U1 .    L1
-  ///                * U2 .    L2
-  ///                ============
-  ///           0 .       . L1*L2
-  ///     +     0 . U1*L2 .     0 // (shift left once by a digit-size)
-  ///     +     0 . U2*L1 .     0 // (shift left once by a digit-size)
-  ///     + U1*L2 .     0 .     0 // (shift left twice by a digit-size)
-  ///
-  /// BlockMass has 64-bit numbers.  Split each into two 32-bit digits, stored
-  /// 64-bit.  Add 1 to the lower digits, to model isFull as 1.0; this won't
-  /// overflow, since we have 64-bit storage for each digit.
-  ///
-  /// To do this accurately, (a) multiply into two 64-bit digits, incrementing
-  /// the upper digit on overflows of the lower digit (carry), (b) subtract 1
-  /// from the lower digit, decrementing the upper digit on underflow (carry),
-  /// and (c) truncate the lower digit.  For the 1.0*1.0 case, the upper digit
-  /// will be 0 at the end of step (a), and then will underflow back to isFull
-  /// (1.0) in step (b).
-  ///
-  /// Instead, the implementation does something a little faster with a small
-  /// loss of accuracy: ignore the lower 64-bit digit entirely.  The loss of
-  /// accuracy is small, since the sum of the unmodelled carries is 0 or 1
-  /// (i.e., step (a) will overflow at most once, and step (b) will underflow
-  /// only if step (a) overflows).
-  ///
-  /// This is the formula we're calculating:
-  ///
-  ///     U1.L1 * U2.L2 == U1 * U2 + (U1 * (L2+1))>>32 + (U2 * (L1+1))>>32
-  ///
-  /// As a demonstration of 1.0*1.0, consider two 4-bit numbers that are both
-  /// full (1111).
-  ///
-  ///     U1.L1 * U2.L2 == U1 * U2 + (U1 * (L2+1))>>2 + (U2 * (L1+1))>>2
-  ///     11.11 * 11.11 == 11 * 11 + (11 * (11+1))/4 + (11 * (11+1))/4
-  ///                   == 1001 + (11 * 100)/4 + (11 * 100)/4
-  ///                   == 1001 + 1100/4 + 1100/4
-  ///                   == 1001 + 0011 + 0011
-  ///                   == 1111
-  BlockMass &operator*=(const BlockMass &X) {
-    uint64_t U1 = Mass >> 32, L1 = Mass & UINT32_MAX, U2 = X.Mass >> 32,
-             L2 = X.Mass & UINT32_MAX;
-    Mass = U1 * U2 + (U1 * (L2 + 1) >> 32) + ((L1 + 1) * U2 >> 32);
-    return *this;
+  bool isBackedge(BlockT *Src, BlockT *Dst) const {
+    unsigned a = RPO.lookup(Src);
+    if (!a)
+      return false;
+    unsigned b = RPO.lookup(Dst);
+    assert(b && "Destination block should be reachable");
+    return a >= b;
   }
 
-  /// \brief Multiply by a branch probability.
-  ///
-  /// Multiply by P.  Guarantees full precision.
-  ///
-  /// This could be naively implemented by multiplying by the numerator and
-  /// dividing by the denominator, but in what order?  Multiplying first can
-  /// overflow, while dividing first will lose precision (potentially, changing
-  /// a non-zero mass to zero).
-  ///
-  /// The implementation mixes the two methods.  Since \a BranchProbability
-  /// uses 32-bits and \a BlockMass 64-bits, shift the mass as far to the left
-  /// as there is room, then divide by the denominator to get a quotient.
-  /// Multiplying by the numerator and right shifting gives a first
-  /// approximation.
-  ///
-  /// Calculate the error in this first approximation by calculating the
-  /// opposite mass (multiply by the opposite numerator and shift) and
-  /// subtracting both from teh original mass.
-  ///
-  /// Add to the first approximation the correct fraction of this error value.
-  /// This time, multiply first and then divide, since there is no danger of
-  /// overflow.
-  ///
-  /// \pre P represents a fraction between 0.0 and 1.0.
-  BlockMass &operator*=(const BranchProbability &P);
-
-  bool operator==(const BlockMass &X) const { return Mass == X.Mass; }
-  bool operator!=(const BlockMass &X) const { return Mass != X.Mass; }
-  bool operator<=(const BlockMass &X) const { return Mass <= X.Mass; }
-  bool operator>=(const BlockMass &X) const { return Mass >= X.Mass; }
-  bool operator<(const BlockMass &X) const { return Mass < X.Mass; }
-  bool operator>(const BlockMass &X) const { return Mass > X.Mass; }
+  /// getSingleBlockPred - return single BB block predecessor or NULL if
+  /// BB has none or more predecessors.
+  BlockT *getSingleBlockPred(BlockT *BB) {
+    typename GT::ChildIteratorType
+      PI = GraphTraits< Inverse<BlockT *> >::child_begin(BB),
+      PE = GraphTraits< Inverse<BlockT *> >::child_end(BB);
 
-  /// \brief Convert to floating point.
-  ///
-  /// Convert to a float.  \a isFull() gives 1.0, while \a isEmpty() gives
-  /// slightly above 0.0.
-  PositiveFloat<uint64_t> toFloat() const;
+    if (PI == PE)
+      return nullptr;
 
-  void dump() const;
-  raw_ostream &print(raw_ostream &OS) const;
-};
+    BlockT *Pred = *PI;
 
-inline BlockMass operator+(const BlockMass &L, const BlockMass &R) {
-  return BlockMass(L) += R;
-}
-inline BlockMass operator-(const BlockMass &L, const BlockMass &R) {
-  return BlockMass(L) -= R;
-}
-inline BlockMass operator*(const BlockMass &L, const BlockMass &R) {
-  return BlockMass(L) *= R;
-}
-inline BlockMass operator*(const BlockMass &L, const BranchProbability &R) {
-  return BlockMass(L) *= R;
-}
-inline BlockMass operator*(const BranchProbability &L, const BlockMass &R) {
-  return BlockMass(R) *= L;
-}
+    ++PI;
+    if (PI != PE)
+      return nullptr;
 
-inline raw_ostream &operator<<(raw_ostream &OS, const BlockMass &X) {
-  return X.print(OS);
-}
-
-template <> struct isPodLike<BlockMass> {
-  static const bool value = true;
-};
-}
+    return Pred;
+  }
 
-//===----------------------------------------------------------------------===//
-//
-// BlockFrequencyInfoImpl definition.
-//
-//===----------------------------------------------------------------------===//
-namespace llvm {
+  void doBlock(BlockT *BB, BlockT *LoopHead,
+               SmallPtrSet<BlockT *, 8> &BlocksInLoop) {
 
-class BasicBlock;
-class BranchProbabilityInfo;
-class Function;
-class Loop;
-class LoopInfo;
-class MachineBasicBlock;
-class MachineBranchProbabilityInfo;
-class MachineFunction;
-class MachineLoop;
-class MachineLoopInfo;
-
-/// \brief Base class for BlockFrequencyInfoImpl
-///
-/// BlockFrequencyInfoImplBase has supporting data structures and some
-/// algorithms for BlockFrequencyInfoImplBase.  Only algorithms that depend on
-/// the block type (or that call such algorithms) are skipped here.
-///
-/// Nevertheless, the majority of the overall algorithm documention lives with
-/// BlockFrequencyInfoImpl.  See there for details.
-class BlockFrequencyInfoImplBase {
-public:
-  typedef PositiveFloat<uint64_t> Float;
+    DEBUG(dbgs() << "doBlock(" << getBlockName(BB) << ")\n");
+    setBlockFreq(BB, 0);
 
-  /// \brief Representative of a block.
-  ///
-  /// This is a simple wrapper around an index into the reverse-post-order
-  /// traversal of the blocks.
-  ///
-  /// Unlike a block pointer, its order has meaning (location in the
-  /// topological sort) and it's class is the same regardless of block type.
-  struct BlockNode {
-    typedef uint32_t IndexType;
-    IndexType Index;
-
-    bool operator==(const BlockNode &X) const { return Index == X.Index; }
-    bool operator!=(const BlockNode &X) const { return Index != X.Index; }
-    bool operator<=(const BlockNode &X) const { return Index <= X.Index; }
-    bool operator>=(const BlockNode &X) const { return Index >= X.Index; }
-    bool operator<(const BlockNode &X) const { return Index < X.Index; }
-    bool operator>(const BlockNode &X) const { return Index > X.Index; }
-
-    BlockNode() : Index(UINT32_MAX) {}
-    BlockNode(IndexType Index) : Index(Index) {}
-
-    bool isValid() const { return Index <= getMaxIndex(); }
-    static size_t getMaxIndex() { return UINT32_MAX - 1; }
-  };
-
-  /// \brief Stats about a block itself.
-  struct FrequencyData {
-    Float Floating;
-    uint64_t Integer;
-  };
-
-  /// \brief Index of loop information.
-  struct WorkingData {
-    BlockNode ContainingLoop; ///< The block whose loop this block is inside.
-    uint32_t LoopIndex;       ///< Index into PackagedLoops.
-    bool IsPackaged;          ///< Has ContainingLoop been packaged up?
-    bool IsAPackage;          ///< Has this block's loop been packaged up?
-    BlockMass Mass;           ///< Mass distribution from the entry block.
-
-    WorkingData()
-        : LoopIndex(UINT32_MAX), IsPackaged(false), IsAPackage(false) {}
-
-    bool hasLoopHeader() const { return ContainingLoop.isValid(); }
-    bool isLoopHeader() const { return LoopIndex != UINT32_MAX; }
-  };
-
-  /// \brief Unscaled probability weight.
-  ///
-  /// Probability weight for an edge in the graph (including the
-  /// successor/target node).
-  ///
-  /// All edges in the original function are 32-bit.  However, exit edges from
-  /// loop packages are taken from 64-bit exit masses, so we need 64-bits of
-  /// space in general.
-  ///
-  /// In addition to the raw weight amount, Weight stores the type of the edge
-  /// in the current context (i.e., the context of the loop being processed).
-  /// Is this a local edge within the loop, an exit from the loop, or a
-  /// backedge to the loop header?
-  struct Weight {
-    enum DistType { Local, Exit, Backedge };
-    DistType Type;
-    BlockNode TargetNode;
-    uint64_t Amount;
-    Weight() : Type(Local), Amount(0) {}
-  };
-
-  /// \brief Distribution of unscaled probability weight.
-  ///
-  /// Distribution of unscaled probability weight to a set of successors.
-  ///
-  /// This class collates the successor edge weights for later processing.
-  ///
-  /// \a DidOverflow indicates whether \a Total did overflow while adding to
-  /// the distribution.  It should never overflow twice.  There's no flag for
-  /// whether \a ForwardTotal overflows, since when \a Total exceeds 32-bits
-  /// they both get re-computed during \a normalize().
-  struct Distribution {
-    typedef SmallVector<Weight, 4> WeightList;
-    WeightList Weights;    ///< Individual successor weights.
-    uint64_t Total;        ///< Sum of all weights.
-    bool DidOverflow;      ///< Whether \a Total did overflow.
-    uint32_t ForwardTotal; ///< Total excluding backedges.
-
-    Distribution() : Total(0), DidOverflow(false), ForwardTotal(0) {}
-    void addLocal(const BlockNode &Node, uint64_t Amount) {
-      add(Node, Amount, Weight::Local);
+    if (BB == LoopHead) {
+      setBlockFreq(BB, EntryFreq);
+      return;
     }
-    void addExit(const BlockNode &Node, uint64_t Amount) {
-      add(Node, Amount, Weight::Exit);
+
+    if (BlockT *Pred = getSingleBlockPred(BB)) {
+      if (BlocksInLoop.count(Pred))
+        setBlockFreq(BB, getEdgeFreq(Pred, BB));
+      // TODO: else? irreducible, ignore it for now.
+      return;
     }
-    void addBackedge(const BlockNode &Node, uint64_t Amount) {
-      add(Node, Amount, Weight::Backedge);
+
+    bool isInLoop = false;
+    bool isLoopHead = false;
+
+    for (typename GT::ChildIteratorType
+         PI = GraphTraits< Inverse<BlockT *> >::child_begin(BB),
+         PE = GraphTraits< Inverse<BlockT *> >::child_end(BB);
+         PI != PE; ++PI) {
+      BlockT *Pred = *PI;
+
+      if (isBackedge(Pred, BB)) {
+        isLoopHead = true;
+      } else if (BlocksInLoop.count(Pred)) {
+        incBlockFreq(BB, getEdgeFreq(Pred, BB));
+        isInLoop = true;
+      }
+      // TODO: else? irreducible.
     }
 
-    /// \brief Normalize the distribution.
-    ///
-    /// Combines multiple edges to the same \a Weight::TargetNode and scales
-    /// down so that \a Total fits into 32-bits.
-    ///
-    /// This is linear in the size of \a Weights.  For the vast majority of
-    /// cases, adjacent edge weights are combined by sorting WeightList and
-    /// combining adjacent weights.  However, for very large edge lists an
-    /// auxiliary hash table is used.
-    void normalize();
-
-  private:
-    void add(const BlockNode &Node, uint64_t Amount, Weight::DistType Type);
-  };
-
-  /// \brief Data for a packaged loop.
-  ///
-  /// Contains the data necessary to represent represent a loop as a node once
-  /// it's packaged.
-  ///
-  /// PackagedLoopData inherits from BlockData to give the node the necessary
-  /// stats.  Further, it has a list of successors, list of members, and stores
-  /// the backedge mass assigned to this loop.
-  struct PackagedLoopData {
-    typedef SmallVector<std::pair<BlockNode, BlockMass>, 4> ExitMap;
-    typedef SmallVector<BlockNode, 4> MemberList;
-    BlockNode Header;       ///< Header.
-    ExitMap Exits;          ///< Successor edges (and weights).
-    MemberList Members;     ///< Members of the loop.
-    BlockMass BackedgeMass; ///< Mass returned to loop header.
-    BlockMass Mass;
-    Float Scale;
-
-    PackagedLoopData(const BlockNode &Header) : Header(Header) {}
-  };
-
-  /// \brief Data about each block.  This is used downstream.
-  std::vector<FrequencyData> Freqs;
-
-  /// \brief Loop data: see initializeLoops().
-  std::vector<WorkingData> Working;
-
-  /// \brief Indexed information about packaged loops.
-  std::vector<PackagedLoopData> PackagedLoops;
-
-  /// \brief Create the initial loop packages.
-  ///
-  /// Initializes PackagedLoops using the data in Working about backedges
-  /// and containing loops.  Called by initializeLoops().
-  ///
-  /// \post WorkingData::LoopIndex has been initialized for every loop header
-  /// and PackagedLoopData::Members has been initialized.
+    if (!isInLoop)
+      return;
 
-  /// \brief Add all edges out of a packaged loop to the distribution.
-  ///
-  /// Adds all edges from LocalLoopHead to Dist.  Calls addToDist() to add each
-  /// successor edge.
-  void addLoopSuccessorsToDist(const BlockNode &LoopHead,
-                               const BlockNode &LocalLoopHead,
-                               Distribution &Dist);
+    if (!isLoopHead)
+      return;
 
-  /// \brief Add an edge to the distribution.
-  ///
-  /// Adds an edge to Succ to Dist.  If \c LoopHead.isValid(), then whether the
-  /// edge is forward/exit/backedge is in the context of LoopHead.  Otherwise,
-  /// every edge should be a forward edge (since all the loops are packaged
-  /// up).
-  void addToDist(Distribution &Dist, const BlockNode &LoopHead,
-                 const BlockNode &Pred, const BlockNode &Succ, uint64_t Weight);
-
-  PackagedLoopData &getLoopPackage(const BlockNode &Head) {
-    assert(Head.Index < Working.size());
-    size_t Index = Working[Head.Index].LoopIndex;
-    assert(Index < PackagedLoops.size());
-    return PackagedLoops[Index];
+    // This block is a loop header, so boost its frequency by the expected
+    // number of loop iterations. The loop blocks will be revisited so they all
+    // get this boost.
+    typename LoopExitProbMap::const_iterator I = LoopExitProb.find(BB);
+    assert(I != LoopExitProb.end() && "Loop header missing from table");
+    Freqs[BB] /= I->second;
+    DEBUG(dbgs() << "Loop header scaled to ";
+          printBlockFreq(dbgs(), Freqs[BB]) << ".\n");
   }
 
-  /// \brief Distribute mass according to a distribution.
-  ///
-  /// Distributes the mass in Source according to Dist.  If LoopHead.isValid(),
-  /// backedges and exits are stored in its entry in PackagedLoops.
-  ///
-  /// Mass is distributed in parallel from two copies of the source mass.
-  ///
-  /// The first mass (forward) represents the distribution of mass through the
-  /// local DAG.  This distribution should lose mass at loop exits and ignore
-  /// backedges.
-  ///
-  /// The second mass (general) represents the behavior of the loop in the
-  /// global context.  In a given distribution from the head, how much mass
-  /// exits, and to where?  How much mass returns to the loop head?
-  ///
-  /// The forward mass should be split up between local successors and exits,
-  /// but only actually distributed to the local successors.  The general mass
-  /// should be split up between all three types of successors, but distributed
-  /// only to exits and backedges.
-  void distributeMass(const BlockNode &Source, const BlockNode &LoopHead,
-                      Distribution &Dist);
+  /// doLoop - Propagate block frequency down through the loop.
+  void doLoop(BlockT *Head, BlockT *Tail) {
+    DEBUG(dbgs() << "doLoop(" << getBlockName(Head) << ", "
+                 << getBlockName(Tail) << ")\n");
 
-  /// \brief Compute the loop scale for a loop.
-  void computeLoopScale(const BlockNode &LoopHead);
+    SmallPtrSet<BlockT *, 8> BlocksInLoop;
 
-  /// \brief Package up a loop.
-  void packageLoop(const BlockNode &LoopHead);
+    for (rpot_iterator I = rpot_at(Head), E = rpot_at(Tail); ; ++I) {
+      BlockT *BB = *I;
+      doBlock(BB, Head, BlocksInLoop);
 
-  /// \brief Finalize frequency metrics.
-  ///
-  /// Unwraps loop packages, calculates final frequencies, and cleans up
-  /// no-longer-needed data structures.
-  void finalizeMetrics();
-
-  /// \brief Clear all memory.
-  void clear();
-
-  virtual std::string getBlockName(const BlockNode &Node) const;
-
-  virtual raw_ostream &print(raw_ostream &OS) const { return OS; }
-  void dump() const { print(dbgs()); }
-
-  Float getFloatingBlockFreq(const BlockNode &Node) const;
-
-  BlockFrequency getBlockFreq(const BlockNode &Node) const;
+      BlocksInLoop.insert(BB);
+      if (I == E)
+        break;
+    }
 
-  raw_ostream &printBlockFreq(raw_ostream &OS, const BlockNode &Node) const;
-  raw_ostream &printBlockFreq(raw_ostream &OS,
-                              const BlockFrequency &Freq) const;
+    // Compute loop's cyclic probability using backedges probabilities.
+    BlockFrequency BackFreq;
+    for (typename GT::ChildIteratorType
+         PI = GraphTraits< Inverse<BlockT *> >::child_begin(Head),
+         PE = GraphTraits< Inverse<BlockT *> >::child_end(Head);
+         PI != PE; ++PI) {
+      BlockT *Pred = *PI;
+      assert(Pred);
+      if (isBackedge(Pred, Head))
+        BackFreq += getEdgeFreq(Pred, Head);
+    }
 
-  uint64_t getEntryFreq() const {
-    assert(!Freqs.empty());
-    return Freqs[0].Integer;
+    // The cyclic probability is freq(BackEdges) / freq(Head), where freq(Head)
+    // only counts edges entering the loop, not the loop backedges.
+    // The probability of leaving the loop on each iteration is:
+    //
+    //   ExitProb = 1 - CyclicProb
+    //
+    // The Expected number of loop iterations is:
+    //
+    //   Iterations = 1 / ExitProb
+    //
+    uint64_t D = std::max(getBlockFreq(Head).getFrequency(), UINT64_C(1));
+    uint64_t N = std::max(BackFreq.getFrequency(), UINT64_C(1));
+    if (N < D)
+      N = D - N;
+    else
+      // We'd expect N < D, but rounding and saturation means that can't be
+      // guaranteed.
+      N = 1;
+
+    // Now ExitProb = N / D, make sure it fits in an i32/i32 fraction.
+    assert(N <= D);
+    if (D > UINT32_MAX) {
+      unsigned Shift = 32 - countLeadingZeros(D);
+      D >>= Shift;
+      N >>= Shift;
+      if (N == 0)
+        N = 1;
+    }
+    BranchProbability LEP = BranchProbability(N, D);
+    LoopExitProb.insert(std::make_pair(Head, LEP));
+    DEBUG(dbgs() << "LoopExitProb[" << getBlockName(Head) << "] = " << LEP
+          << " from 1 - ";
+          printBlockFreq(dbgs(), BackFreq) << " / ";
+          printBlockFreq(dbgs(), getBlockFreq(Head)) << ".\n");
   }
-  /// \brief Virtual destructor.
-  ///
-  /// Need a virtual destructor to mask the compiler warning about
-  /// getBlockName().
-  virtual ~BlockFrequencyInfoImplBase() {}
-};
-
-namespace bfi_detail {
-template <class BlockT> struct TypeMap {};
-template <> struct TypeMap<BasicBlock> {
-  typedef BasicBlock BlockT;
-  typedef Function FunctionT;
-  typedef BranchProbabilityInfo BranchProbabilityInfoT;
-  typedef Loop LoopT;
-  typedef LoopInfo LoopInfoT;
-};
-template <> struct TypeMap<MachineBasicBlock> {
-  typedef MachineBasicBlock BlockT;
-  typedef MachineFunction FunctionT;
-  typedef MachineBranchProbabilityInfo BranchProbabilityInfoT;
-  typedef MachineLoop LoopT;
-  typedef MachineLoopInfo LoopInfoT;
-};
 
-/// \brief Get the name of a MachineBasicBlock.
-///
-/// Get the name of a MachineBasicBlock.  It's templated so that including from
-/// CodeGen is unnecessary (that would be a layering issue).
-///
-/// This is used mainly for debug output.  The name is similar to
-/// MachineBasicBlock::getFullName(), but skips the name of the function.
-template <class BlockT> std::string getBlockName(const BlockT *BB) {
-  assert(BB && "Unexpected nullptr");
-  auto MachineName = "BB" + Twine(BB->getNumber());
-  if (BB->getBasicBlock())
-    return (MachineName + "[" + BB->getName() + "]").str();
-  return MachineName.str();
-}
-/// \brief Get the name of a BasicBlock.
-template <> inline std::string getBlockName(const BasicBlock *BB) {
-  assert(BB && "Unexpected nullptr");
-  return BB->getName().str();
-}
-}
+  friend class BlockFrequencyInfo;
+  friend class MachineBlockFrequencyInfo;
 
-/// \brief Shared implementation for block frequency analysis.
-///
-/// This is a shared implementation of BlockFrequencyInfo and
-/// MachineBlockFrequencyInfo, and calculates the relative frequencies of
-/// blocks.
-///
-/// This algorithm leverages BlockMass and PositiveFloat to maintain precision,
-/// separates mass distribution from loop scaling, and dithers to eliminate
-/// probability mass loss.
-///
-/// The implementation is split between BlockFrequencyInfoImpl, which knows the
-/// type of graph being modelled (BasicBlock vs. MachineBasicBlock), and
-/// BlockFrequencyInfoImplBase, which doesn't.  The base class uses \a
-/// BlockNode, a wrapper around a uint32_t.  BlockNode is numbered from 0 in
-/// reverse-post order.  This gives two advantages:  it's easy to compare the
-/// relative ordering of two nodes, and maps keyed on BlockT can be represented
-/// by vectors.
-///
-/// This algorithm is O(V+E), unless there is irreducible control flow, in
-/// which case it's O(V*E) in the worst case.
-///
-/// These are the main stages:
-///
-///  0. Reverse post-order traversal (\a initializeRPOT()).
-///
-///     Run a single post-order traversal and save it (in reverse) in RPOT.
-///     All other stages make use of this ordering.  Save a lookup from BlockT
-///     to BlockNode (the index into RPOT) in Nodes.
-///
-///  1. Loop indexing (\a initializeLoops()).
-///
-///     Translate LoopInfo/MachineLoopInfo into a form suitable for the rest of
-///     the algorithm.  In particular, store the immediate members of each loop
-///     in reverse post-order.
-///
-///  2. Calculate mass and scale in loops (\a computeMassInLoops()).
-///
-///     For each loop (bottom-up), distribute mass through the DAG resulting
-///     from ignoring backedges and treating sub-loops as a single pseudo-node.
-///     Track the backedge mass distributed to the loop header, and use it to
-///     calculate the loop scale (number of loop iterations).
-///
-///     Visiting loops bottom-up is a post-order traversal of loop headers.
-///     For each loop, immediate members that represent sub-loops will already
-///     have been visited and packaged into a pseudo-node.
-///
-///     Distributing mass in a loop is a reverse-post-order traversal through
-///     the loop.  Start by assigning full mass to the Loop header.  For each
-///     node in the loop:
-///
-///         - Fetch and categorize the weight distribution for its successors.
-///           If this is a packaged-subloop, the weight distribution is stored
-///           in \a PackagedLoopData::Exits.  Otherwise, fetch it from
-///           BranchProbabilityInfo.
-///
-///         - Each successor is categorized as \a Weight::Local, a normal
-///           forward edge within the current loop, \a Weight::Backedge, a
-///           backedge to the loop header, or \a Weight::Exit, any successor
-///           outside the loop.  The weight, the successor, and its category
-///           are stored in \a Distribution.  There can be multiple edges to
-///           each successor.
-///
-///         - Normalize the distribution:  scale weights down so that their sum
-///           is 32-bits, and coalesce multiple edges to the same node.
-///
-///         - Distribute the mass accordingly, dithering to minimize mass loss,
-///           as described in \a distributeMass().  Mass is distributed in
-///           parallel in two ways: forward, and general.  Local successors
-///           take their mass from the forward mass, while exit and backedge
-///           successors take their mass from the general mass.  Additionally,
-///           exit edges use up (ignored) mass from the forward mass, and local
-///           edges use up (ignored) mass from the general distribution.
-///
-///     Finally, calculate the loop scale from the accumulated backedge mass.
-///
-///  3. Distribute mass in the function (\a computeMassInFunction()).
-///
-///     Finally, distribute mass through the DAG resulting from packaging all
-///     loops in the function.  This uses the same algorithm as distributing
-///     mass in a loop, except that there are no exit or backedge edges.
-///
-///  4. Loop unpackaging and cleanup (\a finalizeMetrics()).
-///
-///     Initialize the frequency to a floating point representation of its
-///     mass.
-///
-///     Visit loops top-down (reverse post-order), scaling the loop header's
-///     frequency by its psuedo-node's mass and loop scale.  Keep track of the
-///     minimum and maximum final frequencies.
-///
-///     Using the min and max frequencies as a guide, translate floating point
-///     frequencies to an appropriate range in uint64_t.
-///
-/// It has some known flaws.
-///
-///   - Irreducible control flow isn't modelled correctly.  In particular,
-///     LoopInfo and MachineLoopInfo ignore irreducible backedges.  The main
-///     result is that irreducible SCCs will under-scaled.  No mass is lost,
-///     but the computed branch weights for the loop pseudo-node will be
-///     incorrect.
-///
-///     Modelling irreducible control flow exactly involves setting up and
-///     solving a group of infinite geometric series.  Such precision is
-///     unlikely to be worthwhile, since most of our algorithms give up on
-///     irreducible control flow anyway.
-///
-///     Nevertheless, we might find that we need to get closer.  If
-///     LoopInfo/MachineLoopInfo flags loops with irreducible control flow
-///     (and/or the function as a whole), we can find the SCCs, compute an
-///     approximate exit frequency for the SCC as a whole, and scale up
-///     accordingly.
-///
-///   - Loop scale is limited to 4096 per loop (2^12) to avoid exhausting
-///     BlockFrequency's 64-bit integer precision.
-template <class BT> class BlockFrequencyInfoImpl : BlockFrequencyInfoImplBase {
-  typedef typename bfi_detail::TypeMap<BT>::BlockT BlockT;
-  typedef typename bfi_detail::TypeMap<BT>::FunctionT FunctionT;
-  typedef typename bfi_detail::TypeMap<BT>::BranchProbabilityInfoT
-  BranchProbabilityInfoT;
-  typedef typename bfi_detail::TypeMap<BT>::LoopT LoopT;
-  typedef typename bfi_detail::TypeMap<BT>::LoopInfoT LoopInfoT;
+  BlockFrequencyInfoImpl() { }
 
-  typedef GraphTraits<const BlockT *> Successor;
-  typedef GraphTraits<Inverse<const BlockT *>> Predecessor;
+  void doFunction(FunctionT *fn, BranchProbabilityInfoT *bpi) {
+    Fn = fn;
+    BPI = bpi;
 
-  const BranchProbabilityInfoT *BPI;
-  const LoopInfoT *LI;
-  const FunctionT *F;
+    // Clear everything.
+    RPO.clear();
+    POT.clear();
+    LoopExitProb.clear();
+    Freqs.clear();
 
-  // All blocks in reverse postorder.
-  std::vector<const BlockT *> RPOT;
-  DenseMap<const BlockT *, BlockNode> Nodes;
+    BlockT *EntryBlock = fn->begin();
 
-  typedef typename std::vector<const BlockT *>::const_iterator rpot_iterator;
+    std::copy(po_begin(EntryBlock), po_end(EntryBlock), std::back_inserter(POT));
 
-  rpot_iterator rpot_begin() const { return RPOT.begin(); }
-  rpot_iterator rpot_end() const { return RPOT.end(); }
+    unsigned RPOidx = 0;
+    for (rpot_iterator I = rpot_begin(), E = rpot_end(); I != E; ++I) {
+      BlockT *BB = *I;
+      RPO[BB] = ++RPOidx;
+      DEBUG(dbgs() << "RPO[" << getBlockName(BB) << "] = " << RPO[BB] << "\n");
+    }
 
-  size_t getIndex(const rpot_iterator &I) const { return I - rpot_begin(); }
+    // Travel over all blocks in postorder.
+    for (pot_iterator I = pot_begin(), E = pot_end(); I != E; ++I) {
+      BlockT *BB = *I;
+      BlockT *LastTail = nullptr;
+      DEBUG(dbgs() << "POT: " << getBlockName(BB) << "\n");
 
-  BlockNode getNode(const rpot_iterator &I) const {
-    return BlockNode(getIndex(I));
-  }
-  BlockNode getNode(const BlockT *BB) const { return Nodes.lookup(BB); }
+      for (typename GT::ChildIteratorType
+           PI = GraphTraits< Inverse<BlockT *> >::child_begin(BB),
+           PE = GraphTraits< Inverse<BlockT *> >::child_end(BB);
+           PI != PE; ++PI) {
 
-  const BlockT *getBlock(const BlockNode &Node) const {
-    assert(Node.Index < RPOT.size());
-    return RPOT[Node.Index];
-  }
-
-  void initializeRPOT();
-  void initializeLoops();
-  void runOnFunction(const FunctionT *F);
+        BlockT *Pred = *PI;
+        if (isBackedge(Pred, BB) && (!LastTail || RPO[Pred] > RPO[LastTail]))
+          LastTail = Pred;
+      }
 
-  void propagateMassToSuccessors(const BlockNode &LoopHead,
-                                 const BlockNode &Node);
-  void computeMassInLoops();
-  void computeMassInLoop(const BlockNode &LoopHead);
-  void computeMassInFunction();
+      if (LastTail)
+        doLoop(BB, LastTail);
+    }
 
-  std::string getBlockName(const BlockNode &Node) const override {
-    return bfi_detail::getBlockName(getBlock(Node));
+    // At the end assume the whole function as a loop, and travel over it once
+    // again.
+    doLoop(*(rpot_begin()), *(pot_begin()));
   }
 
 public:
-  const FunctionT *getFunction() const { return F; }
 
-  void doFunction(const FunctionT *F, const BranchProbabilityInfoT *BPI,
-                  const LoopInfoT *LI);
-  BlockFrequencyInfoImpl() : BPI(0), LI(0), F(0) {}
+  uint64_t getEntryFreq() { return EntryFreq; }
 
-  using BlockFrequencyInfoImplBase::getEntryFreq;
+  /// getBlockFreq - Return block frequency. Return 0 if we don't have it.
   BlockFrequency getBlockFreq(const BlockT *BB) const {
-    return BlockFrequencyInfoImplBase::getBlockFreq(getNode(BB));
-  }
-  Float getFloatingBlockFreq(const BlockT *BB) const {
-    return BlockFrequencyInfoImplBase::getFloatingBlockFreq(getNode(BB));
-  }
-
-  /// \brief Print the frequencies for the current function.
-  ///
-  /// Prints the frequencies for the blocks in the current function.
-  ///
-  /// Blocks are printed in the natural iteration order of the function, rather
-  /// than reverse post-order.  This provides two advantages:  writing -analyze
-  /// tests is easier (since blocks come out in source order), and even
-  /// unreachable blocks are printed.
-  ///
-  /// \a BlockFrequencyInfoImplBase::print() only knows reverse post-order, so
-  /// we need to override it here.
-  raw_ostream &print(raw_ostream &OS) const override;
-  using BlockFrequencyInfoImplBase::dump;
-
-  using BlockFrequencyInfoImplBase::printBlockFreq;
-  raw_ostream &printBlockFreq(raw_ostream &OS, const BlockT *BB) const {
-    return BlockFrequencyInfoImplBase::printBlockFreq(OS, getNode(BB));
-  }
-};
-
-template <class BT>
-void BlockFrequencyInfoImpl<BT>::doFunction(const FunctionT *F,
-                                            const BranchProbabilityInfoT *BPI,
-                                            const LoopInfoT *LI) {
-  // Save the parameters.
-  this->BPI = BPI;
-  this->LI = LI;
-  this->F = F;
-
-  // Clean up left-over data structures.
-  BlockFrequencyInfoImplBase::clear();
-  RPOT.clear();
-  Nodes.clear();
-
-  // Initialize.
-  DEBUG(dbgs() << "\nblock-frequency: " << F->getName() << "\n================="
-               << std::string(F->getName().size(), '=') << "\n");
-  initializeRPOT();
-  initializeLoops();
-
-  // Visit loops in post-order to find thelocal mass distribution, and then do
-  // the full function.
-  computeMassInLoops();
-  computeMassInFunction();
-  finalizeMetrics();
-}
-
-template <class BT> void BlockFrequencyInfoImpl<BT>::initializeRPOT() {
-  const BlockT *Entry = F->begin();
-  RPOT.reserve(F->size());
-  std::copy(po_begin(Entry), po_end(Entry), std::back_inserter(RPOT));
-  std::reverse(RPOT.begin(), RPOT.end());
-
-  assert(RPOT.size() - 1 <= BlockNode::getMaxIndex() &&
-         "More nodes in function than Block Frequency Info supports");
-
-  DEBUG(dbgs() << "reverse-post-order-traversal\n");
-  for (rpot_iterator I = rpot_begin(), E = rpot_end(); I != E; ++I) {
-    BlockNode Node = getNode(I);
-    DEBUG(dbgs() << " - " << getIndex(I) << ": " << getBlockName(Node) << "\n");
-    Nodes[*I] = Node;
+    typename DenseMap<const BlockT *, BlockFrequency>::const_iterator
+      I = Freqs.find(BB);
+    if (I != Freqs.end())
+      return I->second;
+    return 0;
   }
 
-  Working.resize(RPOT.size());
-  Freqs.resize(RPOT.size());
-}
-
-template <class BT> void BlockFrequencyInfoImpl<BT>::initializeLoops() {
-  DEBUG(dbgs() << "loop-detection\n");
-  if (LI->empty())
-    return;
-
-  // Visit loops top down and assign them an index.
-  std::deque<const LoopT *> Q;
-  Q.insert(Q.end(), LI->begin(), LI->end());
-  while (!Q.empty()) {
-    const LoopT *Loop = Q.front();
-    Q.pop_front();
-    Q.insert(Q.end(), Loop->begin(), Loop->end());
-
-    // Save the order this loop was visited.
-    BlockNode Header = getNode(Loop->getHeader());
-    assert(Header.isValid());
-
-    Working[Header.Index].LoopIndex = PackagedLoops.size();
-    PackagedLoops.emplace_back(Header);
-    DEBUG(dbgs() << " - loop = " << getBlockName(Header) << "\n");
+  void print(raw_ostream &OS) const {
+    OS << "\n\n---- Block Freqs ----\n";
+    for (typename FunctionT::iterator I = Fn->begin(), E = Fn->end(); I != E;) {
+      BlockT *BB = I++;
+      OS << " " << getBlockName(BB) << " = ";
+      printBlockFreq(OS, getBlockFreq(BB)) << "\n";
+
+      for (typename GraphTraits<BlockT *>::ChildIteratorType
+           SI = GraphTraits<BlockT *>::child_begin(BB),
+           SE = GraphTraits<BlockT *>::child_end(BB); SI != SE; ++SI) {
+        BlockT *Succ = *SI;
+        OS << "  " << getBlockName(BB) << " -> " << getBlockName(Succ)
+           << " = "; printBlockFreq(OS, getEdgeFreq(BB, Succ)) << "\n";
+      }
+    }
   }
 
-  // Visit nodes in reverse post-order and add them to their deepest containing
-  // loop.
-  for (size_t Index = 0; Index < RPOT.size(); ++Index) {
-    const LoopT *Loop = LI->getLoopFor(RPOT[Index]);
-    if (!Loop)
-      continue;
-
-    // If this is a loop header, find its parent loop (if any).
-    if (Working[Index].isLoopHeader())
-      if (!(Loop = Loop->getParentLoop()))
-        continue;
-
-    // Add this node to its containing loop's member list.
-    BlockNode Header = getNode(Loop->getHeader());
-    assert(Header.isValid());
-    const auto &HeaderData = Working[Header.Index];
-    assert(HeaderData.isLoopHeader());
-
-    Working[Index].ContainingLoop = Header;
-    PackagedLoops[HeaderData.LoopIndex].Members.push_back(Index);
-    DEBUG(dbgs() << " - loop = " << getBlockName(Header)
-                 << ": member = " << getBlockName(Index) << "\n");
+  void dump() const {
+    print(dbgs());
   }
-}
-
-template <class BT> void BlockFrequencyInfoImpl<BT>::computeMassInLoops() {
-  // Visit loops with the deepest first, and the top-level loops last.
-  for (auto L = PackagedLoops.rbegin(), LE = PackagedLoops.rend(); L != LE; ++L)
-    computeMassInLoop(L->Header);
-}
-
-template <class BT>
-void BlockFrequencyInfoImpl<BT>::computeMassInLoop(const BlockNode &LoopHead) {
-  // Compute mass in loop.
-  DEBUG(dbgs() << "compute-mass-in-loop: " << getBlockName(LoopHead) << "\n");
-
-  Working[LoopHead.Index].Mass = BlockMass::getFull();
-  propagateMassToSuccessors(LoopHead, LoopHead);
-
-  for (const BlockNode &M : getLoopPackage(LoopHead).Members)
-    propagateMassToSuccessors(LoopHead, M);
-
-  computeLoopScale(LoopHead);
-  packageLoop(LoopHead);
-}
 
-template <class BT> void BlockFrequencyInfoImpl<BT>::computeMassInFunction() {
-  // Compute mass in function.
-  DEBUG(dbgs() << "compute-mass-in-function\n");
-  assert(!Working.empty() && "no blocks in function");
-  assert(!Working[0].isLoopHeader() && "entry block is a loop header");
-
-  Working[0].Mass = BlockMass::getFull();
-  for (rpot_iterator I = rpot_begin(), IE = rpot_end(); I != IE; ++I) {
-    // Check for nodes that have been packaged.
-    BlockNode Node = getNode(I);
-    if (Working[Node.Index].hasLoopHeader())
-      continue;
-
-    propagateMassToSuccessors(BlockNode(), Node);
+  // Utility method that looks up the block frequency associated with BB and
+  // prints it to OS.
+  raw_ostream &printBlockFreq(raw_ostream &OS,
+                              const BlockT *BB) {
+    return printBlockFreq(OS, getBlockFreq(BB));
   }
-}
 
-template <class BT>
-void
-BlockFrequencyInfoImpl<BT>::propagateMassToSuccessors(const BlockNode &LoopHead,
-                                                      const BlockNode &Node) {
-  DEBUG(dbgs() << " - node: " << getBlockName(Node) << "\n");
-  // Calculate probability for successors.
-  Distribution Dist;
-  if (Node != LoopHead && Working[Node.Index].isLoopHeader())
-    addLoopSuccessorsToDist(LoopHead, Node, Dist);
-  else {
-    const BlockT *BB = getBlock(Node);
-    for (auto SI = Successor::child_begin(BB), SE = Successor::child_end(BB);
-         SI != SE; ++SI)
-      // Do not dereference SI, or getEdgeWeight() is linear in the number of
-      // successors.
-      addToDist(Dist, LoopHead, Node, getNode(*SI), BPI->getEdgeWeight(BB, SI));
+  raw_ostream &printBlockFreq(raw_ostream &OS,
+                              const BlockFrequency &Freq) const {
+    // Convert fixed-point number to decimal.
+    uint64_t Frequency = Freq.getFrequency();
+    OS << Frequency / EntryFreq << ".";
+    uint64_t Rem = Frequency % EntryFreq;
+    uint64_t Eps = 1;
+    do {
+      Rem *= 10;
+      Eps *= 10;
+      OS << Rem / EntryFreq;
+      Rem = Rem % EntryFreq;
+    } while (Rem >= Eps/2);
+    return OS;
   }
 
-  // Distribute mass to successors, saving exit and backedge data in the
-  // loop header.
-  distributeMass(Node, LoopHead, Dist);
-}
+};
 
-template <class BT>
-raw_ostream &BlockFrequencyInfoImpl<BT>::print(raw_ostream &OS) const {
-  if (!F)
-    return OS;
-  OS << "block-frequency-info: " << F->getName() << "\n";
-  for (const BlockT &BB : *F)
-    OS << " - " << bfi_detail::getBlockName(&BB)
-       << ": float = " << getFloatingBlockFreq(&BB)
-       << ", int = " << getBlockFreq(&BB).getFrequency() << "\n";
-
-  // Add an extra newline for readability.
-  OS << "\n";
-  return OS;
-}
 }
 
 #endif
diff --git a/lib/Analysis/BlockFrequencyInfo.cpp b/lib/Analysis/BlockFrequencyInfo.cpp
index 13ab29a94d..39aef9e140 100644
--- a/lib/Analysis/BlockFrequencyInfo.cpp
+++ b/lib/Analysis/BlockFrequencyInfo.cpp
@@ -11,7 +11,6 @@
 //
 //===----------------------------------------------------------------------===//
 
-#define DEBUG_TYPE "block-freq"
 #include "llvm/Analysis/BlockFrequencyInfo.h"
 #include "llvm/Analysis/BlockFrequencyInfoImpl.h"
 #include "llvm/Analysis/BranchProbabilityInfo.h"
@@ -107,7 +106,6 @@ struct DOTGraphTraits<BlockFrequencyInfo*> : public DefaultDOTGraphTraits {
 INITIALIZE_PASS_BEGIN(BlockFrequencyInfo, "block-freq",
                       "Block Frequency Analysis", true, true)
 INITIALIZE_PASS_DEPENDENCY(BranchProbabilityInfo)
-INITIALIZE_PASS_DEPENDENCY(LoopInfo)
 INITIALIZE_PASS_END(BlockFrequencyInfo, "block-freq",
                     "Block Frequency Analysis", true, true)
 
@@ -122,16 +120,14 @@ BlockFrequencyInfo::~BlockFrequencyInfo() {}
 
 void BlockFrequencyInfo::getAnalysisUsage(AnalysisUsage &AU) const {
   AU.addRequired<BranchProbabilityInfo>();
-  AU.addRequired<LoopInfo>();
   AU.setPreservesAll();
 }
 
 bool BlockFrequencyInfo::runOnFunction(Function &F) {
   BranchProbabilityInfo &BPI = getAnalysis<BranchProbabilityInfo>();
-  LoopInfo &LI = getAnalysis<LoopInfo>();
   if (!BFI)
     BFI.reset(new ImplType);
-  BFI->doFunction(&F, &BPI, &LI);
+  BFI->doFunction(&F, &BPI);
 #ifndef NDEBUG
   if (ViewBlockFreqPropagationDAG != GVDT_None)
     view();
@@ -162,7 +158,7 @@ void BlockFrequencyInfo::view() const {
 }
 
 const Function *BlockFrequencyInfo::getFunction() const {
-  return BFI ? BFI->getFunction() : nullptr;
+  return BFI ? BFI->Fn : nullptr;
 }
 
 raw_ostream &BlockFrequencyInfo::
diff --git a/lib/Analysis/BlockFrequencyInfoImpl.cpp b/lib/Analysis/BlockFrequencyInfoImpl.cpp
deleted file mode 100644
index e7424aebd7..0000000000
--- a/lib/Analysis/BlockFrequencyInfoImpl.cpp
+++ /dev/null
@@ -1,932 +0,0 @@
-//===- BlockFrequencyImplInfo.cpp - Block Frequency Info Implementation ---===//
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-//
-// Loops should be simplified before this analysis.
-//
-//===----------------------------------------------------------------------===//
-
-#define DEBUG_TYPE "block-freq"
-#include "llvm/Analysis/BlockFrequencyInfoImpl.h"
-#include "llvm/ADT/APFloat.h"
-#include "llvm/Support/raw_ostream.h"
-#include <deque>
-
-using namespace llvm;
-
-//===----------------------------------------------------------------------===//
-//
-// PositiveFloat implementation.
-//
-//===----------------------------------------------------------------------===//
-#ifndef _MSC_VER
-const int32_t PositiveFloatBase::MaxExponent;
-const int32_t PositiveFloatBase::MinExponent;
-#endif
-
-static void appendDigit(std::string &Str, unsigned D) {
-  assert(D < 10);
-  Str += '0' + D % 10;
-}
-
-static void appendNumber(std::string &Str, uint64_t N) {
-  while (N) {
-    appendDigit(Str, N % 10);
-    N /= 10;
-  }
-}
-
-static bool doesRoundUp(char Digit) {
-  switch (Digit) {
-  case '5':
-  case '6':
-  case '7':
-  case '8':
-  case '9':
-    return true;
-  default:
-    return false;
-  }
-}
-
-static std::string toStringAPFloat(uint64_t D, int E, unsigned Precision) {
-  assert(E >= PositiveFloatBase::MinExponent);
-  assert(E <= PositiveFloatBase::MaxExponent);
-
-  // Find a new E, but don't let it increase past MaxExponent.
-  int LeadingZeros = PositiveFloatBase::countLeadingZeros64(D);
-  int NewE = std::min(PositiveFloatBase::MaxExponent, E + 63 - LeadingZeros);
-  int Shift = 63 - (NewE - E);
-  assert(Shift <= LeadingZeros);
-  assert(Shift == LeadingZeros || NewE == PositiveFloatBase::MaxExponent);
-  D <<= Shift;
-  E = NewE;
-
-  // Check for a denormal.
-  unsigned AdjustedE = E + 16383;
-  if (!(D >> 63)) {
-    assert(E == PositiveFloatBase::MaxExponent);
-    AdjustedE = 0;
-  }
-
-  // Build the float and print it.
-  uint64_t RawBits[2] = {D, AdjustedE};
-  APFloat Float(APFloat::x87DoubleExtended, APInt(80, RawBits));
-  SmallVector<char, 24> Chars;
-  Float.toString(Chars, Precision, 0);
-  return std::string(Chars.begin(), Chars.end());
-}
-
-static std::string stripTrailingZeros(const std::string &Float) {
-  size_t NonZero = Float.find_last_not_of('0');
-  assert(NonZero != std::string::npos && "no . in floating point string");
-
-  if (Float[NonZero] == '.')
-    ++NonZero;
-
-  return Float.substr(0, NonZero + 1);
-}
-
-std::string PositiveFloatBase::toString(uint64_t D, int16_t E, int Width,
-                                        unsigned Precision) {
-  if (!D)
-    return "0.0";
-
-  // Canonicalize exponent and digits.
-  uint64_t Above0 = 0;
-  uint64_t Below0 = 0;
-  uint64_t Extra = 0;
-  int ExtraShift = 0;
-  if (E == 0) {
-    Above0 = D;
-  } else if (E > 0) {
-    if (int Shift = std::min(int16_t(countLeadingZeros64(D)), E)) {
-      D <<= Shift;
-      E -= Shift;
-
-      if (!E)
-        Above0 = D;
-    }
-  } else if (E > -64) {
-    Above0 = D >> -E;
-    Below0 = D << (64 + E);
-  } else if (E > -120) {
-    Below0 = D >> (-E - 64);
-    Extra = D << (128 + E);
-    ExtraShift = -64 - E;
-  }
-
-  // Fall back on APFloat for very small and very large numbers.
-  if (!Above0 && !Below0)
-    return toStringAPFloat(D, E, Precision);
-
-  // Append the digits before the decimal.
-  std::string Str;
-  size_t DigitsOut = 0;
-  if (Above0) {
-    appendNumber(Str, Above0);
-    DigitsOut = Str.size();
-  } else
-    appendDigit(Str, 0);
-  std::reverse(Str.begin(), Str.end());
-
-  // Return early if there's nothing after the decimal.
-  if (!Below0)
-    return Str + ".0";
-
-  // Append the decimal and beyond.
-  Str += '.';
-  uint64_t Error = UINT64_C(1) << (64 - Width);
-
-  // We need to shift Below0 to the right to make space for calculating
-  // digits.  Save the precision we're losing in Extra.
-  Extra = (Below0 & 0xf) << 56 | (Extra >> 8);
-  Below0 >>= 4;
-  size_t SinceDot = 0;
-  size_t AfterDot = Str.size();
-  do {
-    if (ExtraShift) {
-      --ExtraShift;
-      Error *= 5;
-    } else
-      Error *= 10;
-
-    Below0 *= 10;
-    Extra *= 10;
-    Below0 += (Extra >> 60);
-    Extra = Extra & (UINT64_MAX >> 4);
-    appendDigit(Str, Below0 >> 60);
-    Below0 = Below0 & (UINT64_MAX >> 4);
-    if (DigitsOut || Str.back() != '0')
-      ++DigitsOut;
-    ++SinceDot;
-  } while (Error && (Below0 << 4 | Extra >> 60) >= Error / 2 &&
-           (!Precision || DigitsOut <= Precision || SinceDot < 2));
-
-  // Return early for maximum precision.
-  if (!Precision || DigitsOut <= Precision)
-    return stripTrailingZeros(Str);
-
-  // Find where to truncate.
-  size_t Truncate =
-      std::max(Str.size() - (DigitsOut - Precision), AfterDot + 1);
-
-  // Check if there's anything to truncate.
-  if (Truncate >= Str.size())
-    return stripTrailingZeros(Str);
-
-  bool Carry = doesRoundUp(Str[Truncate]);
-  if (!Carry)
-    return stripTrailingZeros(Str.substr(0, Truncate));
-
-  // Round with the first truncated digit.
-  for (std::string::reverse_iterator I(Str.begin() + Truncate), E = Str.rend();
-       I != E; ++I) {
-    if (*I == '.')
-      continue;
-    if (*I == '9') {
-      *I = '0';
-      continue;
-    }
-
-    ++*I;
-    Carry = false;
-    break;
-  }
-
-  // Add "1" in front if we still need to carry.
-  return stripTrailingZeros(std::string(Carry, '1') + Str.substr(0, Truncate));
-}
-
-raw_ostream &PositiveFloatBase::print(raw_ostream &OS, uint64_t D, int16_t E,
-                                      int Width, unsigned Precision) {
-  return OS << toString(D, E, Width, Precision);
-}
-
-void PositiveFloatBase::dump(uint64_t D, int16_t E, int Width) {
-  print(dbgs(), D, E, Width, 0) << "[" << Width << ":" << D << "*2^" << E
-                                << "]";
-}
-
-static std::pair<uint64_t, int16_t>
-getRoundedFloat(uint64_t N, bool ShouldRound, int64_t Shift) {
-  if (ShouldRound)
-    if (!++N)
-      // Rounding caused an overflow.
-      return std::make_pair(UINT64_C(1), Shift + 64);
-  return std::make_pair(N, Shift);
-}
-
-std::pair<uint64_t, int16_t> PositiveFloatBase::divide64(uint64_t Dividend,
-                                                         uint64_t Divisor) {
-  // Input should be sanitized.
-  assert(Divisor);
-  assert(Dividend);
-
-  // Minimize size of divisor.
-  int16_t Shift = 0;
-  if (int Zeros = countTrailingZeros(Divisor)) {
-    Shift -= Zeros;
-    Divisor >>= Zeros;
-  }
-
-  // Check for powers of two.
-  if (Divisor == 1)
-    return std::make_pair(Dividend, Shift);
-
-  // Maximize size of dividend.
-  if (int Zeros = countLeadingZeros64(Dividend)) {
-    Shift -= Zeros;
-    Dividend <<= Zeros;
-  }
-
-  // Start with the result of a divide.
-  uint64_t Quotient = Dividend / Divisor;
-  Dividend %= Divisor;
-
-  // Continue building the quotient with long division.
-  //
-  // TODO: continue with largers digits.
-  while (!(Quotient >> 63) && Dividend) {
-    // Shift Dividend, and check for overflow.
-    bool IsOverflow = Dividend >> 63;
-    Dividend <<= 1;
-    --Shift;
-
-    // Divide.
-    bool DoesDivide = IsOverflow || Divisor <= Dividend;
-    Quotient = (Quotient << 1) | uint64_t(DoesDivide);
-    Dividend -= DoesDivide ? Divisor : 0;
-  }
-
-  // Round.
-  if (Dividend >= getHalf(Divisor))
-    if (!++Quotient)
-      // Rounding caused an overflow in Quotient.
-      return std::make_pair(UINT64_C(1), Shift + 64);
-
-  return getRoundedFloat(Quotient, Dividend >= getHalf(Divisor), Shift);
-}
-
-std::pair<uint64_t, int16_t> PositiveFloatBase::multiply64(uint64_t L,
-                                                           uint64_t R) {
-  // Separate into two 32-bit digits (U.L).
-  uint64_t UL = L >> 32, LL = L & UINT32_MAX, UR = R >> 32, LR = R & UINT32_MAX;
-
-  // Compute cross products.
-  uint64_t P1 = UL * UR, P2 = UL * LR, P3 = LL * UR, P4 = LL * LR;
-
-  // Sum into two 64-bit digits.
-  uint64_t Upper = P1, Lower = P4;
-  auto addWithCarry = [&](uint64_t N) {
-    uint64_t NewLower = Lower + (N << 32);
-    Upper += (N >> 32) + (NewLower < Lower);
-    Lower = NewLower;
-  };
-  addWithCarry(P2);
-  addWithCarry(P3);
-
-  // Check whether the upper digit is empty.
-  if (!Upper)
-    return std::make_pair(Lower, 0);
-
-  // Shift as little as possible to maximize precision.
-  unsigned LeadingZeros = countLeadingZeros64(Upper);
-  int16_t Shift = 64 - LeadingZeros;
-  if (LeadingZeros)
-    Upper = Upper << LeadingZeros | Lower >> Shift;
-  bool ShouldRound = Shift && (Lower & UINT64_C(1) << (Shift - 1));
-  return getRoundedFloat(Upper, ShouldRound, Shift);
-}
-
-//===----------------------------------------------------------------------===//
-//
-// BlockMass implementation.
-//
-//===----------------------------------------------------------------------===//
-BlockMass &BlockMass::operator*=(const BranchProbability &P) {
-  uint32_t N = P.getNumerator(), D = P.getDenominator();
-  assert(D && "divide by 0");
-  assert(N <= D && "fraction greater than 1");
-
-  // Fast path for multiplying by 1.0.
-  if (!Mass || N == D)
-    return *this;
-
-  // Get as much precision as we can.
-  int Shift = countLeadingZeros(Mass);
-  uint64_t ShiftedQuotient = (Mass << Shift) / D;
-  uint64_t Product = ShiftedQuotient * N >> Shift;
-
-  // Now check for what's lost.
-  uint64_t Left = ShiftedQuotient * (D - N) >> Shift;
-  uint64_t Lost = Mass - Product - Left;
-
-  // TODO: prove this assertion.
-  assert(Lost <= UINT32_MAX);
-
-  // Take the product plus a portion of the spoils.
-  Mass = Product + Lost * N / D;
-  return *this;
-}
-
-PositiveFloat<uint64_t> BlockMass::toFloat() const {
-  if (isFull())
-    return PositiveFloat<uint64_t>(1, 0);
-  return PositiveFloat<uint64_t>(getMass() + 1, -64);
-}
-
-void BlockMass::dump() const { print(dbgs()); }
-
-static char getHexDigit(int N) {
-  assert(N < 16);
-  if (N < 10)
-    return '0' + N;
-  return 'a' + N - 10;
-}
-raw_ostream &BlockMass::print(raw_ostream &OS) const {
-  for (int Digits = 0; Digits < 16; ++Digits)
-    OS << getHexDigit(Mass >> (60 - Digits * 4) & 0xf);
-  return OS;
-}
-
-//===----------------------------------------------------------------------===//
-//
-// BlockFrequencyInfoImpl implementation.
-//
-//===----------------------------------------------------------------------===//
-namespace {
-
-typedef BlockFrequencyInfoImplBase::BlockNode BlockNode;
-typedef BlockFrequencyInfoImplBase::Distribution Distribution;
-typedef BlockFrequencyInfoImplBase::Distribution::WeightList WeightList;
-typedef BlockFrequencyInfoImplBase::Float Float;
-typedef BlockFrequencyInfoImplBase::PackagedLoopData PackagedLoopData;
-typedef BlockFrequencyInfoImplBase::Weight Weight;
-typedef BlockFrequencyInfoImplBase::FrequencyData FrequencyData;
-
-/// \brief Dithering mass distributer.
-///
-/// This class splits up a single mass into portions by weight, dithering to
-/// spread out error.  No mass is lost.  The dithering precision depends on the
-/// precision of the product of \a BlockMass and \a BranchProbability.
-///
-/// The distribution algorithm follows.
-///
-///  1. Initialize by saving the sum of the weights in \a RemWeight and the
-///     mass to distribute in \a RemMass.
-///
-///  2. For each portion:
-///
-///      1. Construct a branch probability, P, as the portion's weight divided
-///         by the current value of \a RemWeight.
-///      2. Calculate the portion's mass as \a RemMass times P.
-///      3. Update \a RemWeight and \a RemMass at each portion by subtracting
-///         the current portion's weight and mass.
-///
-/// Mass is distributed in two ways: full distribution and forward
-/// distribution.  The latter ignores backedges, and uses the parallel fields
-/// \a RemForwardWeight and \a RemForwardMass.
-struct DitheringDistributer {
-  uint32_t RemWeight;
-  uint32_t RemForwardWeight;
-
-  BlockMass RemMass;
-  BlockMass RemForwardMass;
-
-  DitheringDistributer(Distribution &Dist, const BlockMass &Mass);
-
-  BlockMass takeLocalMass(uint32_t Weight) {
-    (void)takeMass(Weight);
-    return takeForwardMass(Weight);
-  }
-  BlockMass takeExitMass(uint32_t Weight) {
-    (void)takeForwardMass(Weight);
-    return takeMass(Weight);
-  }
-  BlockMass takeBackedgeMass(uint32_t Weight) { return takeMass(Weight); }
-
-private:
-  BlockMass takeForwardMass(uint32_t Weight);
-  BlockMass takeMass(uint32_t Weight);
-};
-}
-
-DitheringDistributer::DitheringDistributer(Distribution &Dist,
-                                           const BlockMass &Mass) {
-  Dist.normalize();
-  RemWeight = Dist.Total;
-  RemForwardWeight = Dist.ForwardTotal;
-  RemMass = Mass;
-  RemForwardMass = Dist.ForwardTotal ? Mass : BlockMass();
-}
-
-BlockMass DitheringDistributer::takeForwardMass(uint32_t Weight) {
-  // Compute the amount of mass to take.
-  assert(Weight && "invalid weight");
-  assert(Weight <= RemForwardWeight);
-  BlockMass Mass = RemForwardMass * BranchProbability(Weight, RemForwardWeight);
-
-  // Decrement totals (dither).
-  RemForwardWeight -= Weight;
-  RemForwardMass -= Mass;
-  return Mass;
-}
-BlockMass DitheringDistributer::takeMass(uint32_t Weight) {
-  assert(Weight && "invalid weight");
-  assert(Weight <= RemWeight);
-  BlockMass Mass = RemMass * BranchProbability(Weight, RemWeight);
-
-  // Decrement totals (dither).
-  RemWeight -= Weight;
-  RemMass -= Mass;
-  return Mass;
-}
-
-void Distribution::add(const BlockNode &Node, uint64_t Amount,
-                       Weight::DistType Type) {
-  assert(Amount && "invalid weight of 0");
-  uint64_t NewTotal = Total + Amount;
-
-  // Check for overflow.  It should be impossible to overflow twice.
-  bool IsOverflow = NewTotal < Total;
-  assert(!(DidOverflow && IsOverflow) && "unexpected repeated overflow");
-  DidOverflow |= IsOverflow;
-
-  // Update the total.
-  Total = NewTotal;
-
-  // Save the weight.
-  Weight W;
-  W.TargetNode = Node;
-  W.Amount = Amount;
-  W.Type = Type;
-  Weights.push_back(W);
-
-  if (Type == Weight::Backedge)
-    return;
-
-  // Update forward total.  Don't worry about overflow here, since then Total
-  // will exceed 32-bits and they'll both be recomputed in normalize().
-  ForwardTotal += Amount;
-}
-
-static void combineWeight(Weight &W, const Weight &OtherW) {
-  assert(OtherW.TargetNode.isValid());
-  if (!W.Amount) {
-    W = OtherW;
-    return;
-  }
-  assert(W.Type == OtherW.Type);
-  assert(W.TargetNode == OtherW.TargetNode);
-  assert(W.Amount < W.Amount + OtherW.Amount);
-  W.Amount += OtherW.Amount;
-}
-static void combineWeightsBySorting(WeightList &Weights) {
-  // Sort so edges to the same node are adjacent.
-  std::sort(Weights.begin(), Weights.end(),
-            [](const Weight &L,
-               const Weight &R) { return L.TargetNode < R.TargetNode; });
-
-  // Combine adjacent edges.
-  WeightList::iterator O = Weights.begin();
-  for (WeightList::const_iterator I = O, L = O, E = Weights.end(); I != E;
-       ++O, (I = L)) {
-    *O = *I;
-
-    // Find the adjacent weights to the same node.
-    for (++L; L != E && I->TargetNode == L->TargetNode; ++L)
-      combineWeight(*O, *L);
-  }
-
-  // Erase extra entries.
-  Weights.erase(O, Weights.end());
-  return;
-}
-static void combineWeightsByHashing(WeightList &Weights) {
-  // Collect weights into a DenseMap.
-  typedef DenseMap<BlockNode::IndexType, Weight> HashTable;
-  HashTable Combined(NextPowerOf2(2 * Weights.size()));
-  for (const Weight &W : Weights)
-    combineWeight(Combined[W.TargetNode.Index], W);
-
-  // Check whether anything changed.
-  if (Weights.size() == Combined.size())
-    return;
-
-  // Fill in the new weights.
-  Weights.clear();
-  Weights.reserve(Combined.size());
-  for (const auto &I : Combined)
-    Weights.push_back(I.second);
-}
-static void combineWeights(WeightList &Weights) {
-  // Use a hash table for many successors to keep this linear.
-  if (Weights.size() > 128) {
-    combineWeightsByHashing(Weights);
-    return;
-  }
-
-  combineWeightsBySorting(Weights);
-}
-static uint64_t shiftRightAndRound(uint64_t N, int Shift) {
-  assert(Shift >= 0);
-  assert(Shift < 64);
-  if (!Shift)
-    return N;
-  return (N >> Shift) + (UINT64_C(1) & N >> (Shift - 1));
-}
-void Distribution::normalize() {
-  // Early exit for termination nodes.
-  if (Weights.empty())
-    return;
-
-  // Only bother if there are multiple successors.
-  if (Weights.size() > 1)
-    combineWeights(Weights);
-
-  // Early exit when combined into a single successor.
-  if (Weights.size() == 1) {
-    Total = 1;
-    ForwardTotal = Weights.front().Type != Weight::Backedge;
-    Weights.front().Amount = 1;
-    return;
-  }
-
-  // Determine how much to shift right so that the total fits into 32-bits.
-  //
-  // If we shift at all, shift by 1 extra.  Otherwise, the lower limit of 1
-  // for each weight can cause a 32-bit overflow.
-  int Shift = 0;
-  if (DidOverflow)
-    Shift = 33;
-  else if (Total > UINT32_MAX)
-    Shift = 33 - countLeadingZeros(Total);
-
-  // Early exit if nothing needs to be scaled.
-  if (!Shift)
-    return;
-
-  // Recompute the total through accumulation (rather than shifting it) so that
-  // it's accurate after shifting.  ForwardTotal is dirty here anyway.
-  Total = 0;
-  ForwardTotal = 0;
-
-  // Sum the weights to each node and shift right if necessary.
-  for (Weight &W : Weights) {
-    // Scale down below UINT32_MAX.  Since Shift is larger than necessary, we
-    // can round here without concern about overflow.
-    assert(W.TargetNode.isValid());
-    W.Amount = std::max(UINT64_C(1), shiftRightAndRound(W.Amount, Shift));
-    assert(W.Amount <= UINT32_MAX);
-
-    // Update the total.
-    Total += W.Amount;
-    if (W.Type == Weight::Backedge)
-      continue;
-
-    // Update the forward total.
-    ForwardTotal += W.Amount;
-  }
-  assert(Total <= UINT32_MAX);
-}
-
-void BlockFrequencyInfoImplBase::clear() {
-  *this = BlockFrequencyInfoImplBase();
-}
-
-/// \brief Clear all memory not needed downstream.
-///
-/// Releases all memory not used downstream.  In particular, saves Freqs.
-static void cleanup(BlockFrequencyInfoImplBase &BFI) {
-  std::vector<FrequencyData> SavedFreqs(std::move(BFI.Freqs));
-  BFI.clear();
-  BFI.Freqs = std::move(SavedFreqs);
-}
-
-/// \brief Get a possibly packaged node.
-///
-/// Get the node currently representing Node, which could be a containing
-/// loop.
-///
-/// This function should only be called when distributing mass.  As long as
-/// there are no irreducilbe edges to Node, then it will have complexity O(1)
-/// in this context.
-///
-/// In general, the complexity is O(L), where L is the number of loop headers
-/// Node has been packaged into.  Since this method is called in the context
-/// of distributing mass, L will be the number of loop headers an early exit
-/// edge jumps out of.
-static BlockNode getPackagedNode(const BlockFrequencyInfoImplBase &BFI,
-                                 const BlockNode &Node) {
-  assert(Node.isValid());
-  if (!BFI.Working[Node.Index].IsPackaged)
-    return Node;
-  if (!BFI.Working[Node.Index].ContainingLoop.isValid())
-    return Node;
-  return getPackagedNode(BFI, BFI.Working[Node.Index].ContainingLoop);
-}
-
-/// \brief Get the appropriate mass for a possible pseudo-node loop package.
-///
-/// Get appropriate mass for Node.  If Node is a loop-header (whose loop has
-/// been packaged), returns the mass of its pseudo-node.  If it's a node inside
-/// a packaged loop, it returns the loop's pseudo-node.
-static BlockMass &getPackageMass(BlockFrequencyInfoImplBase &BFI,
-                                 const BlockNode &Node) {
-  assert(Node.isValid());
-  assert(!BFI.Working[Node.Index].IsPackaged);
-  if (!BFI.Working[Node.Index].IsAPackage)
-    return BFI.Working[Node.Index].Mass;
-
-  return BFI.getLoopPackage(Node).Mass;
-}
-
-void BlockFrequencyInfoImplBase::addToDist(Distribution &Dist,
-                                           const BlockNode &LoopHead,
-                                           const BlockNode &Pred,
-                                           const BlockNode &Succ,
-                                           uint64_t Weight) {
-  if (!Weight)
-    Weight = 1;
-
-#ifndef NDEBUG
-  auto debugSuccessor = [&](const char *Type, const BlockNode &Resolved) {
-    dbgs() << "  =>"
-           << " [" << Type << "] weight = " << Weight;
-    if (Succ != LoopHead)
-      dbgs() << ", succ = " << getBlockName(Succ);
-    if (Resolved != Succ)
-      dbgs() << ", resolved = " << getBlockName(Resolved);
-    dbgs() << "\n";
-  };
-  (void)debugSuccessor;
-#endif
-
-  if (Succ == LoopHead) {
-    DEBUG(debugSuccessor("backedge", Succ));
-    Dist.addBackedge(LoopHead, Weight);
-    return;
-  }
-  BlockNode Resolved = getPackagedNode(*this, Succ);
-  assert(Resolved != LoopHead);
-
-  if (Working[Resolved.Index].ContainingLoop != LoopHead) {
-    DEBUG(debugSuccessor("  exit  ", Resolved));
-    Dist.addExit(Resolved, Weight);
-    return;
-  }
-
-  if (!LoopHead.isValid() && Resolved < Pred) {
-    // Irreducible backedge.  Skip this edge in the distribution.
-    DEBUG(debugSuccessor("skipped ", Resolved));
-    return;
-  }
-
-  DEBUG(debugSuccessor(" local  ", Resolved));
-  Dist.addLocal(Resolved, Weight);
-}
-
-void BlockFrequencyInfoImplBase::addLoopSuccessorsToDist(
-    const BlockNode &LoopHead, const BlockNode &LocalLoopHead,
-    Distribution &Dist) {
-  PackagedLoopData &LoopPackage = getLoopPackage(LocalLoopHead);
-  const PackagedLoopData::ExitMap &Exits = LoopPackage.Exits;
-
-  // Copy the exit map into Dist.
-  for (const auto &I : Exits)
-    addToDist(Dist, LoopHead, LocalLoopHead, I.first, I.second.getMass());
-
-  // We don't need this map any more.  Clear it to prevent quadratic memory
-  // usage in deeply nested loops with irreducible control flow.
-  LoopPackage.Exits.clear();
-}
-
-/// \brief Get the maximum allowed loop scale.
-///
-/// Gives the maximum number of estimated iterations allowed for a loop.
-/// Downstream users have trouble with very large numbers (even within
-/// 64-bits).  Perhaps they can be changed to use PositiveFloat.
-///
-/// TODO: change downstream users so that this can be increased or removed.
-static Float getMaxLoopScale() { return Float(1, 12); }
-
-/// \brief Compute the loop scale for a loop.
-void BlockFrequencyInfoImplBase::computeLoopScale(const BlockNode &LoopHead) {
-  // Compute loop scale.
-  DEBUG(dbgs() << "compute-loop-scale: " << getBlockName(LoopHead) << "\n");
-
-  // LoopScale == 1 / ExitMass
-  // ExitMass == HeadMass - BackedgeMass
-  PackagedLoopData &LoopPackage = getLoopPackage(LoopHead);
-  BlockMass ExitMass = BlockMass::getFull() - LoopPackage.BackedgeMass;
-
-  // Block scale stores the inverse of the scale.
-  LoopPackage.Scale = ExitMass.toFloat().inverse();
-
-  DEBUG(dbgs() << " - exit-mass = " << ExitMass << " (" << BlockMass::getFull()
-               << " - " << LoopPackage.BackedgeMass << ")\n"
-               << " - scale = " << LoopPackage.Scale << "\n");
-
-  if (LoopPackage.Scale > getMaxLoopScale()) {
-    LoopPackage.Scale = getMaxLoopScale();
-    DEBUG(dbgs() << " - reduced-to-max-scale: " << getMaxLoopScale() << "\n");
-  }
-}
-
-/// \brief Package up a loop.
-void BlockFrequencyInfoImplBase::packageLoop(const BlockNode &LoopHead) {
-  DEBUG(dbgs() << "packaging-loop: " << getBlockName(LoopHead) << "\n");
-  Working[LoopHead.Index].IsAPackage = true;
-  for (const BlockNode &M : getLoopPackage(LoopHead).Members) {
-    DEBUG(dbgs() << " - node: " << getBlockName(M.Index) << "\n");
-    Working[M.Index].IsPackaged = true;
-  }
-}
-
-void BlockFrequencyInfoImplBase::distributeMass(const BlockNode &Source,
-                                                const BlockNode &LoopHead,
-                                                Distribution &Dist) {
-  BlockMass Mass = getPackageMass(*this, Source);
-  DEBUG(dbgs() << "  => mass:  " << Mass
-               << " (    general     |    forward     )\n");
-
-  // Distribute mass to successors as laid out in Dist.
-  DitheringDistributer D(Dist, Mass);
-
-#ifndef NDEBUG
-  auto debugAssign = [&](const BlockNode &T, const BlockMass &M,
-                         const char *Desc) {
-    dbgs() << "  => assign " << M << " (" << D.RemMass << "|"
-           << D.RemForwardMass << ")";
-    if (Desc)
-      dbgs() << " [" << Desc << "]";
-    if (T.isValid())
-      dbgs() << " to " << getBlockName(T);
-    dbgs() << "\n";
-  };
-  (void)debugAssign;
-#endif
-
-  PackagedLoopData *LoopPackage = 0;
-  if (LoopHead.isValid())
-    LoopPackage = &getLoopPackage(LoopHead);
-  for (const Weight &W : Dist.Weights) {
-    // Check for a local edge (forward and non-exit).
-    if (W.Type == Weight::Local) {
-      BlockMass Local = D.takeLocalMass(W.Amount);
-      getPackageMass(*this, W.TargetNode) += Local;
-      DEBUG(debugAssign(W.TargetNode, Local, nullptr));
-      continue;
-    }
-
-    // Backedges and exits only make sense if we're processing a loop.
-    assert(LoopPackage && "backedge or exit outside of loop");
-
-    // Check for a backedge.
-    if (W.Type == Weight::Backedge) {
-      BlockMass Back = D.takeBackedgeMass(W.Amount);
-      LoopPackage->BackedgeMass += Back;
-      DEBUG(debugAssign(BlockNode(), Back, "back"));
-      continue;
-    }
-
-    // This must be an exit.
-    assert(W.Type == Weight::Exit);
-    BlockMass Exit = D.takeExitMass(W.Amount);
-    LoopPackage->Exits.push_back(std::make_pair(W.TargetNode, Exit));
-    DEBUG(debugAssign(W.TargetNode, Exit, "exit"));
-  }
-}
-
-static void convertFloatingToInteger(BlockFrequencyInfoImplBase &BFI,
-                                     const Float &Min, const Float &Max) {
-  // Scale the Factor to a size that creates integers.  Ideally, integers would
-  // be scaled so that Max == UINT64_MAX so that they can be best
-  // differentiated.  However, the register allocator currently deals poorly
-  // with large numbers.  Instead, push Min up a little from 1 to give some
-  // room to differentiate small, unequal numbers.
-  //
-  // TODO: fix issues downstream so that ScalingFactor can be Float(1,64)/Max.
-  Float ScalingFactor = Min.inverse();
-  if ((Max / Min).lg() < 60)
-    ScalingFactor <<= 3;
-
-  // Translate the floats to integers.
-  DEBUG(dbgs() << "float-to-int: min = " << Min << ", max = " << Max
-               << ", factor = " << ScalingFactor << "\n");
-  for (size_t Index = 0; Index < BFI.Freqs.size(); ++Index) {
-    Float Scaled = BFI.Freqs[Index].Floating * ScalingFactor;
-    BFI.Freqs[Index].Integer = std::max(UINT64_C(1), Scaled.toInt<uint64_t>());
-    DEBUG(dbgs() << " - " << BFI.getBlockName(Index) << ": float = "
-                 << BFI.Freqs[Index].Floating << ", scaled = " << Scaled
-                 << ", int = " << BFI.Freqs[Index].Integer << "\n");
-  }
-}
-
-static void scaleBlockData(BlockFrequencyInfoImplBase &BFI,
-                           const BlockNode &Node,
-                           const PackagedLoopData &Loop) {
-  Float F = Loop.Mass.toFloat() * Loop.Scale;
-
-  Float &Current = BFI.Freqs[Node.Index].Floating;
-  Float Updated = Current * F;
-
-  DEBUG(dbgs() << " - " << BFI.getBlockName(Node) << ": " << Current << " => "
-               << Updated << "\n");
-
-  Current = Updated;
-}
-
-/// \brief Unwrap a loop package.
-///
-/// Visits all the members of a loop, adjusting their BlockData according to
-/// the loop's pseudo-node.
-static void unwrapLoopPackage(BlockFrequencyInfoImplBase &BFI,
-                              const BlockNode &Head) {
-  assert(Head.isValid());
-
-  PackagedLoopData &LoopPackage = BFI.getLoopPackage(Head);
-  DEBUG(dbgs() << "unwrap-loop-package: " << BFI.getBlockName(Head)
-               << ": mass = " << LoopPackage.Mass
-               << ", scale = " << LoopPackage.Scale << "\n");
-  scaleBlockData(BFI, Head, LoopPackage);
-
-  // Propagate the head scale through the loop.  Since members are visited in
-  // RPO, the head scale will be updated by the loop scale first, and then the
-  // final head scale will be used for updated the rest of the members.
-  for (const BlockNode &M : LoopPackage.Members) {
-    const FrequencyData &HeadData = BFI.Freqs[Head.Index];
-    FrequencyData &Freqs = BFI.Freqs[M.Index];
-    Float NewFreq = Freqs.Floating * HeadData.Floating;
-    DEBUG(dbgs() << " - " << BFI.getBlockName(M) << ": " << Freqs.Floating
-                 << " => " << NewFreq << "\n");
-    Freqs.Floating = NewFreq;
-  }
-}
-
-void BlockFrequencyInfoImplBase::finalizeMetrics() {
-  // Set initial frequencies from loop-local masses.
-  for (size_t Index = 0; Index < Working.size(); ++Index)
-    Freqs[Index].Floating = Working[Index].Mass.toFloat();
-
-  // Unwrap loop packages in reverse post-order, tracking min and max
-  // frequencies.
-  auto Min = Float::getLargest();
-  auto Max = Float::getZero();
-  for (size_t Index = 0; Index < Working.size(); ++Index) {
-    if (Working[Index].isLoopHeader())
-      unwrapLoopPackage(*this, BlockNode(Index));
-
-    // Update max scale.
-    Min = std::min(Min, Freqs[Index].Floating);
-    Max = std::max(Max, Freqs[Index].Floating);
-  }
-
-  // Convert to integers.
-  convertFloatingToInteger(*this, Min, Max);
-
-  // Clean up data structures.
-  cleanup(*this);
-
-  // Print out the final stats.
-  DEBUG(dump());
-}
-
-BlockFrequency
-BlockFrequencyInfoImplBase::getBlockFreq(const BlockNode &Node) const {
-  if (!Node.isValid())
-    return 0;
-  return Freqs[Node.Index].Integer;
-}
-Float
-BlockFrequencyInfoImplBase::getFloatingBlockFreq(const BlockNode &Node) const {
-  if (!Node.isValid())
-    return Float::getZero();
-  return Freqs[Node.Index].Floating;
-}
-
-std::string
-BlockFrequencyInfoImplBase::getBlockName(const BlockNode &Node) const {
-  return std::string();
-}
-
-raw_ostream &
-BlockFrequencyInfoImplBase::printBlockFreq(raw_ostream &OS,
-                                           const BlockNode &Node) const {
-  return OS << getFloatingBlockFreq(Node);
-}
-
-raw_ostream &
-BlockFrequencyInfoImplBase::printBlockFreq(raw_ostream &OS,
-                                           const BlockFrequency &Freq) const {
-  Float Block(Freq.getFrequency(), 0);
-  Float Entry(getEntryFreq(), 0);
-
-  return OS << Block / Entry;
-}
diff --git a/lib/Analysis/CMakeLists.txt b/lib/Analysis/CMakeLists.txt
index 0b0b2f92ea..c6d4573885 100644
--- a/lib/Analysis/CMakeLists.txt
+++ b/lib/Analysis/CMakeLists.txt
@@ -7,7 +7,6 @@ add_llvm_library(LLVMAnalysis
   Analysis.cpp
   BasicAliasAnalysis.cpp
   BlockFrequencyInfo.cpp
-  BlockFrequencyInfoImpl.cpp
   BranchProbabilityInfo.cpp
   CFG.cpp
   CFGPrinter.cpp
diff --git a/lib/CodeGen/MachineBlockFrequencyInfo.cpp b/lib/CodeGen/MachineBlockFrequencyInfo.cpp
index d3ac0c0437..70efa307d5 100644
--- a/lib/CodeGen/MachineBlockFrequencyInfo.cpp
+++ b/lib/CodeGen/MachineBlockFrequencyInfo.cpp
@@ -11,12 +11,9 @@
 //
 //===----------------------------------------------------------------------===//
 
-#define DEBUG_TYPE "block-freq"
 #include "llvm/CodeGen/MachineBlockFrequencyInfo.h"
 #include "llvm/Analysis/BlockFrequencyInfoImpl.h"
 #include "llvm/CodeGen/MachineBranchProbabilityInfo.h"
-#include "llvm/CodeGen/MachineFunction.h"
-#include "llvm/CodeGen/MachineLoopInfo.h"
 #include "llvm/CodeGen/Passes.h"
 #include "llvm/InitializePasses.h"
 #include "llvm/Support/CommandLine.h"
@@ -115,7 +112,6 @@ struct DOTGraphTraits<MachineBlockFrequencyInfo*> :
 INITIALIZE_PASS_BEGIN(MachineBlockFrequencyInfo, "machine-block-freq",
                       "Machine Block Frequency Analysis", true, true)
 INITIALIZE_PASS_DEPENDENCY(MachineBranchProbabilityInfo)
-INITIALIZE_PASS_DEPENDENCY(MachineLoopInfo)
 INITIALIZE_PASS_END(MachineBlockFrequencyInfo, "machine-block-freq",
                     "Machine Block Frequency Analysis", true, true)
 
@@ -131,18 +127,16 @@ MachineBlockFrequencyInfo::~MachineBlockFrequencyInfo() {}
 
 void MachineBlockFrequencyInfo::getAnalysisUsage(AnalysisUsage &AU) const {
   AU.addRequired<MachineBranchProbabilityInfo>();
-  AU.addRequired<MachineLoopInfo>();
   AU.setPreservesAll();
   MachineFunctionPass::getAnalysisUsage(AU);
 }
 
 bool MachineBlockFrequencyInfo::runOnMachineFunction(MachineFunction &F) {
   MachineBranchProbabilityInfo &MBPI =
-      getAnalysis<MachineBranchProbabilityInfo>();
-  MachineLoopInfo &MLI = getAnalysis<MachineLoopInfo>();
+    getAnalysis<MachineBranchProbabilityInfo>();
   if (!MBFI)
     MBFI.reset(new ImplType);
-  MBFI->doFunction(&F, &MBPI, &MLI);
+  MBFI->doFunction(&F, &MBPI);
 #ifndef NDEBUG
   if (ViewMachineBlockFreqPropagationDAG != GVDT_None) {
     view();
@@ -172,7 +166,7 @@ getBlockFreq(const MachineBasicBlock *MBB) const {
 }
 
 const MachineFunction *MachineBlockFrequencyInfo::getFunction() const {
-  return MBFI ? MBFI->getFunction() : nullptr;
+  return MBFI ? MBFI->Fn : nullptr;
 }
 
 raw_ostream &
diff --git a/test/Analysis/BlockFrequencyInfo/bad_input.ll b/test/Analysis/BlockFrequencyInfo/bad_input.ll
deleted file mode 100644
index bcdc1e6f0b..0000000000
--- a/test/Analysis/BlockFrequencyInfo/bad_input.ll
+++ /dev/null
@@ -1,50 +0,0 @@
-; RUN: opt < %s -analyze -block-freq | FileCheck %s
-
-declare void @g(i32 %x)
-
-; CHECK-LABEL: Printing analysis {{.*}} for function 'branch_weight_0':
-; CHECK-NEXT: block-frequency-info: branch_weight_0
-define void @branch_weight_0(i32 %a) {
-; CHECK-NEXT: entry: float = 1.0, int = [[ENTRY:[0-9]+]]
-entry:
-  br label %for.body
-
-; Check that we get 1,4 instead of 0,3.
-; CHECK-NEXT: for.body: float = 4.0,
-for.body:
-  %i = phi i32 [ 0, %entry ], [ %inc, %for.body ]
-  call void @g(i32 %i)
-  %inc = add i32 %i, 1
-  %cmp = icmp ugt i32 %inc, %a
-  br i1 %cmp, label %for.end, label %for.body, !prof !0
-
-; CHECK-NEXT: for.end: float = 1.0, int = [[ENTRY]]
-for.end:
-  ret void
-}
-
-!0 = metadata !{metadata !"branch_weights", i32 0, i32 3}
-
-; CHECK-LABEL: Printing analysis {{.*}} for function 'infinite_loop'
-; CHECK-NEXT: block-frequency-info: infinite_loop
-define void @infinite_loop(i1 %x) {
-; CHECK-NEXT: entry: float = 1.0, int = [[ENTRY:[0-9]+]]
-entry:
-  br i1 %x, label %for.body, label %for.end, !prof !1
-
-; Check that the loop scale maxes out at 4096, giving 2048 here.
-; CHECK-NEXT: for.body: float = 2048.0,
-for.body:
-  %i = phi i32 [ 0, %entry ], [ %inc, %for.body ]
-  call void @g(i32 %i)
-  %inc = add i32 %i, 1
-  br label %for.body
-
-; Check that the exit weight is half of entry, since half is lost in the
-; infinite loop above.
-; CHECK-NEXT: for.end: float = 0.5,
-for.end:
-  ret void
-}
-
-!1 = metadata !{metadata !"branch_weights", i32 1, i32 1}
diff --git a/test/Analysis/BlockFrequencyInfo/basic.ll b/test/Analysis/BlockFrequencyInfo/basic.ll
index 006e6ab4d7..ce29fb5ce1 100644
--- a/test/Analysis/BlockFrequencyInfo/basic.ll
+++ b/test/Analysis/BlockFrequencyInfo/basic.ll
@@ -1,14 +1,13 @@
 ; RUN: opt < %s -analyze -block-freq | FileCheck %s
 
 define i32 @test1(i32 %i, i32* %a) {
-; CHECK-LABEL: Printing analysis {{.*}} for function 'test1':
-; CHECK-NEXT: block-frequency-info: test1
-; CHECK-NEXT: entry: float = 1.0, int = [[ENTRY:[0-9]+]]
+; CHECK: Printing analysis {{.*}} for function 'test1'
+; CHECK: entry = 1.0
 entry:
   br label %body
 
 ; Loop backedges are weighted and thus their bodies have a greater frequency.
-; CHECK-NEXT: body: float = 32.0,
+; CHECK: body = 32.0
 body:
   %iv = phi i32 [ 0, %entry ], [ %next, %body ]
   %base = phi i32 [ 0, %entry ], [ %sum, %body ]
@@ -19,29 +18,29 @@ body:
   %exitcond = icmp eq i32 %next, %i
   br i1 %exitcond, label %exit, label %body
 
-; CHECK-NEXT: exit: float = 1.0, int = [[ENTRY]]
+; CHECK: exit = 1.0
 exit:
   ret i32 %sum
 }
 
 define i32 @test2(i32 %i, i32 %a, i32 %b) {
-; CHECK-LABEL: Printing analysis {{.*}} for function 'test2':
-; CHECK-NEXT: block-frequency-info: test2
-; CHECK-NEXT: entry: float = 1.0, int = [[ENTRY:[0-9]+]]
+; CHECK: Printing analysis {{.*}} for function 'test2'
+; CHECK: entry = 1.0
 entry:
   %cond = icmp ult i32 %i, 42
   br i1 %cond, label %then, label %else, !prof !0
 
 ; The 'then' branch is predicted more likely via branch weight metadata.
-; CHECK-NEXT: then: float = 0.9411{{[0-9]*}},
+; CHECK: then = 0.94116
 then:
   br label %exit
 
-; CHECK-NEXT: else: float = 0.05882{{[0-9]*}},
+; CHECK: else = 0.05877
 else:
   br label %exit
 
-; CHECK-NEXT: exit: float = 1.0, int = [[ENTRY]]
+; FIXME: It may be a bug that we don't sum back to 1.0.
+; CHECK: exit = 0.99993
 exit:
   %result = phi i32 [ %a, %then ], [ %b, %else ]
   ret i32 %result
@@ -50,37 +49,37 @@ exit:
 !0 = metadata !{metadata !"branch_weights", i32 64, i32 4}
 
 define i32 @test3(i32 %i, i32 %a, i32 %b, i32 %c, i32 %d, i32 %e) {
-; CHECK-LABEL: Printing analysis {{.*}} for function 'test3':
-; CHECK-NEXT: block-frequency-info: test3
-; CHECK-NEXT: entry: float = 1.0, int = [[ENTRY:[0-9]+]]
+; CHECK: Printing analysis {{.*}} for function 'test3'
+; CHECK: entry = 1.0
 entry:
   switch i32 %i, label %case_a [ i32 1, label %case_b
                                  i32 2, label %case_c
                                  i32 3, label %case_d
                                  i32 4, label %case_e ], !prof !1
 
-; CHECK-NEXT: case_a: float = 0.05,
+; CHECK: case_a = 0.04998
 case_a:
   br label %exit
 
-; CHECK-NEXT: case_b: float = 0.05,
+; CHECK: case_b = 0.04998
 case_b:
   br label %exit
 
 ; The 'case_c' branch is predicted more likely via branch weight metadata.
-; CHECK-NEXT: case_c: float = 0.8,
+; CHECK: case_c = 0.79998
 case_c:
   br label %exit
 
-; CHECK-NEXT: case_d: float = 0.05,
+; CHECK: case_d = 0.04998
 case_d:
   br label %exit
 
-; CHECK-NEXT: case_e: float = 0.05,
+; CHECK: case_e = 0.04998
 case_e:
   br label %exit
 
-; CHECK-NEXT: exit: float = 1.0, int = [[ENTRY]]
+; FIXME: It may be a bug that we don't sum back to 1.0.
+; CHECK: exit = 0.99993
 exit:
   %result = phi i32 [ %a, %case_a ],
                     [ %b, %case_b ],
@@ -92,50 +91,44 @@ exit:
 
 !1 = metadata !{metadata !"branch_weights", i32 4, i32 4, i32 64, i32 4, i32 4}
 
+; CHECK: Printing analysis {{.*}} for function 'nested_loops'
+; CHECK: entry = 1.0
+; This test doesn't seem to be assigning sensible frequencies to nested loops.
 define void @nested_loops(i32 %a) {
-; CHECK-LABEL: Printing analysis {{.*}} for function 'nested_loops':
-; CHECK-NEXT: block-frequency-info: nested_loops
-; CHECK-NEXT: entry: float = 1.0, int = [[ENTRY:[0-9]+]]
 entry:
   br label %for.cond1.preheader
 
-; CHECK-NEXT: for.cond1.preheader: float = 4001.0,
 for.cond1.preheader:
   %x.024 = phi i32 [ 0, %entry ], [ %inc12, %for.inc11 ]
   br label %for.cond4.preheader
 
-; CHECK-NEXT: for.cond4.preheader: float = 16008001.0,
 for.cond4.preheader:
   %y.023 = phi i32 [ 0, %for.cond1.preheader ], [ %inc9, %for.inc8 ]
   %add = add i32 %y.023, %x.024
   br label %for.body6
 
-; CHECK-NEXT: for.body6: float = 64048012001.0,
 for.body6:
   %z.022 = phi i32 [ 0, %for.cond4.preheader ], [ %inc, %for.body6 ]
   %add7 = add i32 %add, %z.022
-  tail call void @g(i32 %add7)
+  tail call void @g(i32 %add7) #2
   %inc = add i32 %z.022, 1
   %cmp5 = icmp ugt i32 %inc, %a
   br i1 %cmp5, label %for.inc8, label %for.body6, !prof !2
 
-; CHECK-NEXT: for.inc8: float = 16008001.0,
 for.inc8:
   %inc9 = add i32 %y.023, 1
   %cmp2 = icmp ugt i32 %inc9, %a
   br i1 %cmp2, label %for.inc11, label %for.cond4.preheader, !prof !2
 
-; CHECK-NEXT: for.inc11: float = 4001.0,
 for.inc11:
   %inc12 = add i32 %x.024, 1
   %cmp = icmp ugt i32 %inc12, %a
   br i1 %cmp, label %for.end13, label %for.cond1.preheader, !prof !2
 
-; CHECK-NEXT: for.end13: float = 1.0, int = [[ENTRY]]
 for.end13:
   ret void
 }
 
-declare void @g(i32)
+declare void @g(i32) #1
 
 !2 = metadata !{metadata !"branch_weights", i32 1, i32 4000}
diff --git a/test/Analysis/BlockFrequencyInfo/double_exit.ll b/test/Analysis/BlockFrequencyInfo/double_exit.ll
deleted file mode 100644
index 2fe617c9f5..0000000000
--- a/test/Analysis/BlockFrequencyInfo/double_exit.ll
+++ /dev/null
@@ -1,165 +0,0 @@
-; RUN: opt < %s -analyze -block-freq | FileCheck %s
-
-; CHECK-LABEL: Printing analysis {{.*}} for function 'double_exit':
-; CHECK-NEXT: block-frequency-info: double_exit
-define i32 @double_exit(i32 %N) {
-; Mass = 1
-; Frequency = 1
-; CHECK-NEXT: entry: float = 1.0, int = [[ENTRY:[0-9]+]]
-entry:
-  br label %outer
-
-; Mass = 1
-; Backedge mass = 1/3, exit mass = 2/3
-; Loop scale = 3/2
-; Psuedo-edges = exit
-; Psuedo-mass = 1
-; Frequency = 1*3/2*1 = 3/2
-; CHECK-NEXT: outer: float = 1.5,
-outer:
-  %I.0 = phi i32 [ 0, %entry ], [ %inc6, %outer.inc ]
-  %Return.0 = phi i32 [ 0, %entry ], [ %Return.1, %outer.inc ]
-  %cmp = icmp slt i32 %I.0, %N
-  br i1 %cmp, label %inner, label %exit, !prof !2 ; 2:1
-
-; Mass = 1
-; Backedge mass = 3/5, exit mass = 2/5
-; Loop scale = 5/2
-; Pseudo-edges = outer.inc @ 1/5, exit @ 1/5
-; Pseudo-mass = 2/3
-; Frequency = 3/2*1*5/2*2/3 = 5/2
-; CHECK-NEXT: inner: float = 2.5,
-inner:
-  %Return.1 = phi i32 [ %Return.0, %outer ], [ %call4, %inner.inc ]
-  %J.0 = phi i32 [ %I.0, %outer ], [ %inc, %inner.inc ]
-  %cmp2 = icmp slt i32 %J.0, %N
-  br i1 %cmp2, label %inner.body, label %outer.inc, !prof !1 ; 4:1
-
-; Mass = 4/5
-; Frequency = 5/2*4/5 = 2
-; CHECK-NEXT: inner.body: float = 2.0,
-inner.body:
-  %call = call i32 @c2(i32 %I.0, i32 %J.0)
-  %tobool = icmp ne i32 %call, 0
-  br i1 %tobool, label %exit, label %inner.inc, !prof !0 ; 3:1
-
-; Mass = 3/5
-; Frequency = 5/2*3/5 = 3/2
-; CHECK-NEXT: inner.inc: float = 1.5,
-inner.inc:
-  %call4 = call i32 @logic2(i32 %Return.1, i32 %I.0, i32 %J.0)
-  %inc = add nsw i32 %J.0, 1
-  br label %inner
-
-; Mass = 1/3
-; Frequency = 3/2*1/3 = 1/2
-; CHECK-NEXT: outer.inc: float = 0.5,
-outer.inc:
-  %inc6 = add nsw i32 %I.0, 1
-  br label %outer
-
-; Mass = 1
-; Frequency = 1
-; CHECK-NEXT: exit: float = 1.0, int = [[ENTRY]]
-exit:
-  %Return.2 = phi i32 [ %Return.1, %inner.body ], [ %Return.0, %outer ]
-  ret i32 %Return.2
-}
-
-!0 = metadata !{metadata !"branch_weights", i32 1, i32 3}
-!1 = metadata !{metadata !"branch_weights", i32 4, i32 1}
-!2 = metadata !{metadata !"branch_weights", i32 2, i32 1}
-
-declare i32 @c2(i32, i32)
-declare i32 @logic2(i32, i32, i32)
-
-; CHECK-LABEL: Printing analysis {{.*}} for function 'double_exit_in_loop':
-; CHECK-NEXT: block-frequency-info: double_exit_in_loop
-define i32 @double_exit_in_loop(i32 %N) {
-; Mass = 1
-; Frequency = 1
-; CHECK-NEXT: entry: float = 1.0, int = [[ENTRY:[0-9]+]]
-entry:
-  br label %outer
-
-; Mass = 1
-; Backedge mass = 1/2, exit mass = 1/2
-; Loop scale = 2
-; Pseudo-edges = exit
-; Psuedo-mass = 1
-; Frequency = 1*2*1 = 2
-; CHECK-NEXT: outer: float = 2.0,
-outer:
-  %I.0 = phi i32 [ 0, %entry ], [ %inc12, %outer.inc ]
-  %Return.0 = phi i32 [ 0, %entry ], [ %Return.3, %outer.inc ]
-  %cmp = icmp slt i32 %I.0, %N
-  br i1 %cmp, label %middle, label %exit, !prof !3 ; 1:1
-
-; Mass = 1
-; Backedge mass = 1/3, exit mass = 2/3
-; Loop scale = 3/2
-; Psuedo-edges = outer.inc
-; Psuedo-mass = 1/2
-; Frequency = 2*1*3/2*1/2 = 3/2
-; CHECK-NEXT: middle: float = 1.5,
-middle:
-  %J.0 = phi i32 [ %I.0, %outer ], [ %inc9, %middle.inc ]
-  %Return.1 = phi i32 [ %Return.0, %outer ], [ %Return.2, %middle.inc ]
-  %cmp2 = icmp slt i32 %J.0, %N
-  br i1 %cmp2, label %inner, label %outer.inc, !prof !2 ; 2:1
-
-; Mass = 1
-; Backedge mass = 3/5, exit mass = 2/5
-; Loop scale = 5/2
-; Pseudo-edges = middle.inc @ 1/5, outer.inc @ 1/5
-; Pseudo-mass = 2/3
-; Frequency = 3/2*1*5/2*2/3 = 5/2
-; CHECK-NEXT: inner: float = 2.5,
-inner:
-  %Return.2 = phi i32 [ %Return.1, %middle ], [ %call7, %inner.inc ]
-  %K.0 = phi i32 [ %J.0, %middle ], [ %inc, %inner.inc ]
-  %cmp5 = icmp slt i32 %K.0, %N
-  br i1 %cmp5, label %inner.body, label %middle.inc, !prof !1 ; 4:1
-
-; Mass = 4/5
-; Frequency = 5/2*4/5 = 2
-; CHECK-NEXT: inner.body: float = 2.0,
-inner.body:
-  %call = call i32 @c3(i32 %I.0, i32 %J.0, i32 %K.0)
-  %tobool = icmp ne i32 %call, 0
-  br i1 %tobool, label %outer.inc, label %inner.inc, !prof !0 ; 3:1
-
-; Mass = 3/5
-; Frequency = 5/2*3/5 = 3/2
-; CHECK-NEXT: inner.inc: float = 1.5,
-inner.inc:
-  %call7 = call i32 @logic3(i32 %Return.2, i32 %I.0, i32 %J.0, i32 %K.0)
-  %inc = add nsw i32 %K.0, 1
-  br label %inner
-
-; Mass = 1/3
-; Frequency = 3/2*1/3 = 1/2
-; CHECK-NEXT: middle.inc: float = 0.5,
-middle.inc:
-  %inc9 = add nsw i32 %J.0, 1
-  br label %middle
-
-; Mass = 1/2
-; Frequency = 2*1/2 = 1
-; CHECK-NEXT: outer.inc: float = 1.0,
-outer.inc:
-  %Return.3 = phi i32 [ %Return.2, %inner.body ], [ %Return.1, %middle ]
-  %inc12 = add nsw i32 %I.0, 1
-  br label %outer
-
-; Mass = 1
-; Frequency = 1
-; CHECK-NEXT: exit: float = 1.0, int = [[ENTRY]]
-exit:
-  ret i32 %Return.0
-}
-
-!3 = metadata !{metadata !"branch_weights", i32 1, i32 1}
-
-declare i32 @c3(i32, i32, i32)
-declare i32 @logic3(i32, i32, i32, i32)
diff --git a/test/Analysis/BlockFrequencyInfo/irreducible.ll b/test/Analysis/BlockFrequencyInfo/irreducible.ll
deleted file mode 100644
index 46a2958700..0000000000
--- a/test/Analysis/BlockFrequencyInfo/irreducible.ll
+++ /dev/null
@@ -1,197 +0,0 @@
-; RUN: opt < %s -analyze -block-freq | FileCheck %s
-
-; A loop with multiple exits should be handled correctly.
-;
-; CHECK-LABEL: Printing analysis {{.*}} for function 'multiexit':
-; CHECK-NEXT: block-frequency-info: multiexit
-define void @multiexit(i32 %a) {
-; CHECK-NEXT: entry: float = 1.0, int = [[ENTRY:[0-9]+]]
-entry:
-  br label %loop.1
-
-; CHECK-NEXT: loop.1: float = 1.333{{3*}},
-loop.1:
-  %i = phi i32 [ 0, %entry ], [ %inc.2, %loop.2 ]
-  call void @f(i32 %i)
-  %inc.1 = add i32 %i, 1
-  %cmp.1 = icmp ugt i32 %inc.1, %a
-  br i1 %cmp.1, label %exit.1, label %loop.2, !prof !0
-
-; CHECK-NEXT: loop.2: float = 0.666{{6*7}},
-loop.2:
-  call void @g(i32 %inc.1)
-  %inc.2 = add i32 %inc.1, 1
-  %cmp.2 = icmp ugt i32 %inc.2, %a
-  br i1 %cmp.2, label %exit.2, label %loop.1, !prof !1
-
-; CHECK-NEXT: exit.1: float = 0.666{{6*7}},
-exit.1:
-  call void @h(i32 %inc.1)
-  br label %return
-
-; CHECK-NEXT: exit.2: float = 0.333{{3*}},
-exit.2:
-  call void @i(i32 %inc.2)
-  br label %return
-
-; CHECK-NEXT: return: float = 1.0, int = [[ENTRY]]
-return:
-  ret void
-}
-
-declare void @f(i32 %x)
-declare void @g(i32 %x)
-declare void @h(i32 %x)
-declare void @i(i32 %x)
-
-!0 = metadata !{metadata !"branch_weights", i32 3, i32 3}
-!1 = metadata !{metadata !"branch_weights", i32 5, i32 5}
-
-; The current BlockFrequencyInfo algorithm doesn't handle multiple entrances
-; into a loop very well.  The frequencies assigned to blocks in the loop are
-; predictable (and not absurd), but also not correct and therefore not worth
-; testing.
-;
-; There are two testcases below.
-;
-; For each testcase, I use a CHECK-NEXT/NOT combo like an XFAIL with the
-; granularity of a single check.  If/when this behaviour is fixed, we'll know
-; about it, and the test should be updated.
-;
-; Testcase #1
-; ===========
-;
-; In this case c1 and c2 should have frequencies of 15/7 and 13/7,
-; respectively.  To calculate this, consider assigning 1.0 to entry, and
-; distributing frequency iteratively (to infinity).  At the first iteration,
-; entry gives 3/4 to c1 and 1/4 to c2.  At every step after, c1 and c2 give 3/4
-; of what they have to each other.  Somehow, all of it comes out to exit.
-;
-;       c1 = 3/4 + 1/4*3/4 + 3/4*3^2/4^2 + 1/4*3^3/4^3 + 3/4*3^3/4^3 + ...
-;       c2 = 1/4 + 3/4*3/4 + 1/4*3^2/4^2 + 3/4*3^3/4^3 + 1/4*3^3/4^3 + ...
-;
-; Simplify by splitting up the odd and even terms of the series and taking out
-; factors so that the infite series matches:
-;
-;       c1 =  3/4 *(9^0/16^0 + 9^1/16^1 + 9^2/16^2 + ...)
-;          +  3/16*(9^0/16^0 + 9^1/16^1 + 9^2/16^2 + ...)
-;       c2 =  1/4 *(9^0/16^0 + 9^1/16^1 + 9^2/16^2 + ...)
-;          +  9/16*(9^0/16^0 + 9^1/16^1 + 9^2/16^2 + ...)
-;
-;       c1 = 15/16*(9^0/16^0 + 9^1/16^1 + 9^2/16^2 + ...)
-;       c2 = 13/16*(9^0/16^0 + 9^1/16^1 + 9^2/16^2 + ...)
-;
-; Since this geometric series sums to 16/7:
-;
-;       c1 = 15/7
-;       c2 = 13/7
-;
-; If we treat c1 and c2 as members of the same loop, the exit frequency of the
-; loop as a whole is 1/4, so the loop scale should be 4.  Summing c1 and c2
-; gives 28/7, or 4.0, which is nice confirmation of the math above.
-;
-; However, assuming c1 precedes c2 in reverse post-order, the current algorithm
-; returns 3/4 and 13/16, respectively.  LoopInfo ignores edges between loops
-; (and doesn't see any loops here at all), and -block-freq ignores the
-; irreducible edge from c2 to c1.
-;
-; CHECK-LABEL: Printing analysis {{.*}} for function 'multientry':
-; CHECK-NEXT: block-frequency-info: multientry
-define void @multientry(i32 %a) {
-; CHECK-NEXT: entry: float = 1.0, int = [[ENTRY:[0-9]+]]
-entry:
-  %choose = call i32 @choose(i32 %a)
-  %compare = icmp ugt i32 %choose, %a
-  br i1 %compare, label %c1, label %c2, !prof !2
-
-; This is like a single-line XFAIL (see above).
-; CHECK-NEXT: c1:
-; CHECK-NOT: float = 2.142857{{[0-9]*}},
-c1:
-  %i1 = phi i32 [ %a, %entry ], [ %i2.inc, %c2 ]
-  %i1.inc = add i32 %i1, 1
-  %choose1 = call i32 @choose(i32 %i1)
-  %compare1 = icmp ugt i32 %choose1, %a
-  br i1 %compare1, label %c2, label %exit, !prof !2
-
-; This is like a single-line XFAIL (see above).
-; CHECK-NEXT: c2:
-; CHECK-NOT: float = 1.857142{{[0-9]*}},
-c2:
-  %i2 = phi i32 [ %a, %entry ], [ %i1.inc, %c1 ]
-  %i2.inc = add i32 %i2, 1
-  %choose2 = call i32 @choose(i32 %i2)
-  %compare2 = icmp ugt i32 %choose2, %a
-  br i1 %compare2, label %c1, label %exit, !prof !2
-
-; We still shouldn't lose any frequency.
-; CHECK-NEXT: exit: float = 1.0, int = [[ENTRY]]
-exit:
-  ret void
-}
-
-; Testcase #2
-; ===========
-;
-; In this case c1 and c2 should be treated as equals in a single loop.  The
-; exit frequency is 1/3, so the scaling factor for the loop should be 3.0.  The
-; loop is entered 2/3 of the time, and c1 and c2 split the total loop frequency
-; evenly (1/2), so they should each have frequencies of 1.0 (3.0*2/3*1/2).
-; Another way of computing this result is by assigning 1.0 to entry and showing
-; that c1 and c2 should accumulate frequencies of:
-;
-;       1/3   +   2/9   +   4/27  +   8/81  + ...
-;     2^0/3^1 + 2^1/3^2 + 2^2/3^3 + 2^3/3^4 + ...
-;
-; At the first step, c1 and c2 each get 1/3 of the entry.  At each subsequent
-; step, c1 and c2 each get 1/3 of what's left in c1 and c2 combined.  This
-; infinite series sums to 1.
-;
-; However, assuming c1 precedes c2 in reverse post-order, the current algorithm
-; returns 1/2 and 3/4, respectively.  LoopInfo ignores edges between loops (and
-; treats c1 and c2 as self-loops only), and -block-freq ignores the irreducible
-; edge from c2 to c1.
-;
-; Below I use a CHECK-NEXT/NOT combo like an XFAIL with the granularity of a
-; single check.  If/when this behaviour is fixed, we'll know about it, and the
-; test should be updated.
-;
-; CHECK-LABEL: Printing analysis {{.*}} for function 'crossloops':
-; CHECK-NEXT: block-frequency-info: crossloops
-define void @crossloops(i32 %a) {
-; CHECK-NEXT: entry: float = 1.0, int = [[ENTRY:[0-9]+]]
-entry:
-  %choose = call i32 @choose(i32 %a)
-  switch i32 %choose, label %exit [ i32 1, label %c1
-                                    i32 2, label %c2 ], !prof !3
-
-; This is like a single-line XFAIL (see above).
-; CHECK-NEXT: c1:
-; CHECK-NOT: float = 1.0,
-c1:
-  %i1 = phi i32 [ %a, %entry ], [ %i1.inc, %c1 ], [ %i2.inc, %c2 ]
-  %i1.inc = add i32 %i1, 1
-  %choose1 = call i32 @choose(i32 %i1)
-  switch i32 %choose1, label %exit [ i32 1, label %c1
-                                     i32 2, label %c2 ], !prof !3
-
-; This is like a single-line XFAIL (see above).
-; CHECK-NEXT: c2:
-; CHECK-NOT: float = 1.0,
-c2:
-  %i2 = phi i32 [ %a, %entry ], [ %i1.inc, %c1 ], [ %i2.inc, %c2 ]
-  %i2.inc = add i32 %i2, 1
-  %choose2 = call i32 @choose(i32 %i2)
-  switch i32 %choose2, label %exit [ i32 1, label %c1
-                                     i32 2, label %c2 ], !prof !3
-
-; We still shouldn't lose any frequency.
-; CHECK-NEXT: exit: float = 1.0, int = [[ENTRY]]
-exit:
-  ret void
-}
-
-declare i32 @choose(i32)
-
-!2 = metadata !{metadata !"branch_weights", i32 3, i32 1}
-!3 = metadata !{metadata !"branch_weights", i32 2, i32 2, i32 2}
diff --git a/test/Analysis/BlockFrequencyInfo/loop_with_branch.ll b/test/Analysis/BlockFrequencyInfo/loop_with_branch.ll
deleted file mode 100644
index 9d27b6bf0f..0000000000
--- a/test/Analysis/BlockFrequencyInfo/loop_with_branch.ll
+++ /dev/null
@@ -1,44 +0,0 @@
-; RUN: opt < %s -analyze -block-freq | FileCheck %s
-
-; CHECK-LABEL: Printing analysis {{.*}} for function 'loop_with_branch':
-; CHECK-NEXT: block-frequency-info: loop_with_branch
-define void @loop_with_branch(i32 %a) {
-; CHECK-NEXT: entry: float = 1.0, int = [[ENTRY:[0-9]+]]
-entry:
-  %skip_loop = call i1 @foo0(i32 %a)
-  br i1 %skip_loop, label %skip, label %header, !prof !0
-
-; CHECK-NEXT: skip: float = 0.25,
-skip:
-  br label %exit
-
-; CHECK-NEXT: header: float = 4.5,
-header:
-  %i = phi i32 [ 0, %entry ], [ %i.next, %back ]
-  %i.next = add i32 %i, 1
-  %choose = call i2 @foo1(i32 %i)
-  switch i2 %choose, label %exit [ i2 0, label %left
-                                   i2 1, label %right ], !prof !1
-
-; CHECK-NEXT: left: float = 1.5,
-left:
-  br label %back
-
-; CHECK-NEXT: right: float = 2.25,
-right:
-  br label %back
-
-; CHECK-NEXT: back: float = 3.75,
-back:
-  br label %header
-
-; CHECK-NEXT: exit: float = 1.0, int = [[ENTRY]]
-exit:
-  ret void
-}
-
-declare i1 @foo0(i32)
-declare i2 @foo1(i32)
-
-!0 = metadata !{metadata !"branch_weights", i32 1, i32 3}
-!1 = metadata !{metadata !"branch_weights", i32 1, i32 2, i32 3}
diff --git a/test/Analysis/BlockFrequencyInfo/nested_loop_with_branches.ll b/test/Analysis/BlockFrequencyInfo/nested_loop_with_branches.ll
deleted file mode 100644
index d93ffceb5f..0000000000
--- a/test/Analysis/BlockFrequencyInfo/nested_loop_with_branches.ll
+++ /dev/null
@@ -1,59 +0,0 @@
-; RUN: opt < %s -analyze -block-freq | FileCheck %s
-
-; CHECK-LABEL: Printing analysis {{.*}} for function 'nested_loop_with_branches'
-; CHECK-NEXT: block-frequency-info: nested_loop_with_branches
-define void @nested_loop_with_branches(i32 %a) {
-; CHECK-NEXT: entry: float = 1.0, int = [[ENTRY:[0-9]+]]
-entry:
-  %v0 = call i1 @foo0(i32 %a)
-  br i1 %v0, label %exit, label %outer, !prof !0
-
-; CHECK-NEXT: outer: float = 12.0,
-outer:
-  %i = phi i32 [ 0, %entry ], [ %i.next, %inner.end ], [ %i.next, %no_inner ]
-  %i.next = add i32 %i, 1
-  %do_inner = call i1 @foo1(i32 %i)
-  br i1 %do_inner, label %no_inner, label %inner, !prof !0
-
-; CHECK-NEXT: inner: float = 36.0,
-inner:
-  %j = phi i32 [ 0, %outer ], [ %j.next, %inner.end ]
-  %side = call i1 @foo3(i32 %j)
-  br i1 %side, label %left, label %right, !prof !0
-
-; CHECK-NEXT: left: float = 9.0,
-left:
-  %v4 = call i1 @foo4(i32 %j)
-  br label %inner.end
-
-; CHECK-NEXT: right: float = 27.0,
-right:
-  %v5 = call i1 @foo5(i32 %j)
-  br label %inner.end
-
-; CHECK-NEXT: inner.end: float = 36.0,
-inner.end:
-  %stay_inner = phi i1 [ %v4, %left ], [ %v5, %right ]
-  %j.next = add i32 %j, 1
-  br i1 %stay_inner, label %inner, label %outer, !prof !1
-
-; CHECK-NEXT: no_inner: float = 3.0,
-no_inner:
-  %continue = call i1 @foo6(i32 %i)
-  br i1 %continue, label %outer, label %exit, !prof !1
-
-; CHECK-NEXT: exit: float = 1.0, int = [[ENTRY]]
-exit:
-  ret void
-}
-
-declare i1 @foo0(i32)
-declare i1 @foo1(i32)
-declare i1 @foo2(i32)
-declare i1 @foo3(i32)
-declare i1 @foo4(i32)
-declare i1 @foo5(i32)
-declare i1 @foo6(i32)
-
-!0 = metadata !{metadata !"branch_weights", i32 1, i32 3}
-!1 = metadata !{metadata !"branch_weights", i32 3, i32 1}
diff --git a/test/CodeGen/XCore/llvm-intrinsics.ll b/test/CodeGen/XCore/llvm-intrinsics.ll
index b436282615..e0acd66e4a 100644
--- a/test/CodeGen/XCore/llvm-intrinsics.ll
+++ b/test/CodeGen/XCore/llvm-intrinsics.ll
@@ -287,8 +287,9 @@ define void @Unwind1() {
 ; CHECKFP: .LBB{{[0-9_]+}}
 ; CHECKFP-NEXT: ldc r2, 40
 ; CHECKFP-NEXT: add r2, r10, r2
-; CHECKFP-NEXT: add r2, r2, r0
+; CHECKFP-NEXT: add r0, r2, r0
 ; CHECKFP-NEXT: mov r3, r1
+; CHECKFP-NEXT: mov r2, r0
 ; CHECKFP-NEXT: ldw r9, r10[4]
 ; CHECKFP-NEXT: ldw r8, r10[5]
 ; CHECKFP-NEXT: ldw r7, r10[6]
@@ -336,8 +337,9 @@ define void @Unwind1() {
 ; CHECK-NEXT: ldc r2, 36
 ; CHECK-NEXT: ldaw r3, sp[0]
 ; CHECK-NEXT: add r2, r3, r2
-; CHECK-NEXT: add r2, r2, r0
+; CHECK-NEXT: add r0, r2, r0
 ; CHECK-NEXT: mov r3, r1
+; CHECK-NEXT: mov r2, r0
 ; CHECK-NEXT: ldw r10, sp[2]
 ; CHECK-NEXT: ldw r9, sp[3]
 ; CHECK-NEXT: ldw r8, sp[4]