Index: include/llvm/ADT/APInt.h
===================================================================
--- include/llvm/ADT/APInt.h
+++ include/llvm/ADT/APInt.h
@@ -82,7 +82,7 @@
   union {
     uint64_t VAL;   ///< Used to store the <= 64 bits integer value.
     uint64_t *pVal; ///< Used to store the >64 bits integer value.
-  };
+  } U;
 
   /// This enum is used to hold the constants we needed for APInt.
   enum {
@@ -99,7 +99,9 @@
   ///
   /// This constructor is used only internally for speed of construction of
   /// temporaries. It is unsafe for general use so it is not public.
-  APInt(uint64_t *val, unsigned bits) : BitWidth(bits), pVal(val) {}
+  APInt(uint64_t *val, unsigned bits) : BitWidth(bits) {
+    U.pVal = val;
+  }
 
   /// \brief Determine if this APInt just has one word to store value.
   ///
@@ -149,16 +151,16 @@
     // Mask out the high bits.
     uint64_t mask = UINT64_MAX >> (APINT_BITS_PER_WORD - wordBits);
     if (isSingleWord())
-      VAL &= mask;
+      U.VAL &= mask;
     else
-      pVal[getNumWords() - 1] &= mask;
+      U.pVal[getNumWords() - 1] &= mask;
     return *this;
   }
 
   /// \brief Get the word corresponding to a bit position
   /// \returns the corresponding word for the specified bit position.
   uint64_t getWord(unsigned bitPosition) const {
-    return isSingleWord() ? VAL : pVal[whichWord(bitPosition)];
+    return isSingleWord() ? U.VAL : U.pVal[whichWord(bitPosition)];
   }
 
   /// \brief Convert a char array into an APInt
@@ -238,10 +240,10 @@
   /// \param val the initial value of the APInt
   /// \param isSigned how to treat signedness of val
   APInt(unsigned numBits, uint64_t val, bool isSigned = false)
-      : BitWidth(numBits), VAL(0) {
+      : BitWidth(numBits) {
     assert(BitWidth && "bitwidth too small");
     if (isSingleWord()) {
-      VAL = val;
+      U.VAL = val;
       clearUnusedBits();
     } else {
       initSlowCase(val, isSigned);
@@ -281,22 +283,23 @@
 
   /// Simply makes *this a copy of that.
   /// @brief Copy Constructor.
-  APInt(const APInt &that) : BitWidth(that.BitWidth), VAL(0) {
+  APInt(const APInt &that) : BitWidth(that.BitWidth) {
     if (isSingleWord())
-      VAL = that.VAL;
+      U.VAL = that.U.VAL;
     else
       initSlowCase(that);
   }
 
   /// \brief Move Constructor.
-  APInt(APInt &&that) : BitWidth(that.BitWidth), VAL(that.VAL) {
+  APInt(APInt &&that) : BitWidth(that.BitWidth) {
+    memcpy(&U, &that.U, sizeof(U));
     that.BitWidth = 0;
   }
 
   /// \brief Destructor.
   ~APInt() {
     if (needsCleanup())
-      delete[] pVal;
+      delete[] U.pVal;
   }
 
   /// \brief Default constructor that creates an uninteresting APInt
@@ -304,7 +307,7 @@
   ///
   /// This is useful for object deserialization (pair this with the static
   ///  method Read).
-  explicit APInt() : BitWidth(1), VAL(0) {}
+  explicit APInt() : BitWidth(1) { U.VAL = 0; }
 
   /// \brief Returns whether this instance allocated memory.
   bool needsCleanup() const { return !isSingleWord(); }
@@ -342,7 +345,7 @@
   /// This checks to see if the value has all bits of the APInt are set or not.
   bool isAllOnesValue() const {
     if (isSingleWord())
-      return VAL == UINT64_MAX >> (APINT_BITS_PER_WORD - BitWidth);
+      return U.VAL == UINT64_MAX >> (APINT_BITS_PER_WORD - BitWidth);
     return countPopulationSlowCase() == BitWidth;
   }
 
@@ -391,7 +394,7 @@
   /// \returns true if the argument APInt value is a power of two > 0.
   bool isPowerOf2() const {
     if (isSingleWord())
-      return isPowerOf2_64(VAL);
+      return isPowerOf2_64(U.VAL);
     return countPopulationSlowCase() == 1;
   }
 
@@ -576,8 +579,8 @@
   /// conversions.
   const uint64_t *getRawData() const {
     if (isSingleWord())
-      return &VAL;
-    return &pVal[0];
+      return &U.VAL;
+    return &U.pVal[0];
   }
 
   /// @}
@@ -630,10 +633,10 @@
   /// \returns true if *this is zero, false otherwise.
   bool operator!() const {
     if (isSingleWord())
-      return !VAL;
+      return !U.VAL;
 
     for (unsigned i = 0; i != getNumWords(); ++i)
-      if (pVal[i])
+      if (U.pVal[i])
         return false;
     return true;
   }
@@ -648,7 +651,7 @@
   APInt &operator=(const APInt &RHS) {
     // If the bitwidths are the same, we can avoid mucking with memory
     if (isSingleWord() && RHS.isSingleWord()) {
-      VAL = RHS.VAL;
+      U.VAL = RHS.U.VAL;
       BitWidth = RHS.BitWidth;
       return clearUnusedBits();
     }
@@ -664,12 +667,12 @@
       // where half of the output is left in a moved-from state.
       if (this == &that)
         return *this;
-      delete[] pVal;
+      delete[] U.pVal;
     }
 
     // Use memcpy so that type based alias analysis sees both VAL and pVal
     // as modified.
-    memcpy(&VAL, &that.VAL, sizeof(uint64_t));
+    memcpy(&U, &that.U, sizeof(U));
 
     // If 'this == &that', avoid zeroing our own bitwidth by storing to 'that'
     // first.
@@ -719,10 +722,10 @@
   /// the LHS.
   APInt &operator|=(uint64_t RHS) {
     if (isSingleWord()) {
-      VAL |= RHS;
+      U.VAL |= RHS;
       clearUnusedBits();
     } else {
-      pVal[0] |= RHS;
+      U.pVal[0] |= RHS;
     }
     return *this;
   }
@@ -742,10 +745,10 @@
   /// the LHS.
   APInt &operator^=(uint64_t RHS) {
     if (isSingleWord()) {
-      VAL ^= RHS;
+      U.VAL ^= RHS;
       clearUnusedBits();
     } else {
-      pVal[0] ^= RHS;
+      U.pVal[0] ^= RHS;
     }
     return *this;
   }
@@ -795,7 +798,7 @@
   APInt operator&(const APInt &RHS) const {
     assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
     if (isSingleWord())
-      return APInt(getBitWidth(), VAL & RHS.VAL);
+      return APInt(getBitWidth(), U.VAL & RHS.U.VAL);
     return AndSlowCase(RHS);
   }
 
@@ -807,7 +810,7 @@
   APInt operator|(const APInt &RHS) const {
     assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
     if (isSingleWord())
-      return APInt(getBitWidth(), VAL | RHS.VAL);
+      return APInt(getBitWidth(), U.VAL | RHS.U.VAL);
     return OrSlowCase(RHS);
   }
 
@@ -819,7 +822,7 @@
   APInt operator^(const APInt &RHS) const {
     assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
     if (isSingleWord())
-      return APInt(BitWidth, VAL ^ RHS.VAL);
+      return APInt(BitWidth, U.VAL ^ RHS.U.VAL);
     return XorSlowCase(RHS);
   }
 
@@ -856,7 +859,7 @@
     if (isSingleWord()) {
       if (shiftAmt >= BitWidth)
         return APInt(BitWidth, 0); // avoid undefined shift results
-      return APInt(BitWidth, VAL << shiftAmt);
+      return APInt(BitWidth, U.VAL << shiftAmt);
     }
     return shlSlowCase(shiftAmt);
   }
@@ -947,7 +950,7 @@
   bool operator[](unsigned bitPosition) const {
     assert(bitPosition < getBitWidth() && "Bit position out of bounds!");
     return (maskBit(bitPosition) &
-            (isSingleWord() ? VAL : pVal[whichWord(bitPosition)])) !=
+            (isSingleWord() ? U.VAL : U.pVal[whichWord(bitPosition)])) !=
            0;
   }
 
@@ -962,7 +965,7 @@
   bool operator==(const APInt &RHS) const {
     assert(BitWidth == RHS.BitWidth && "Comparison requires equal bit widths");
     if (isSingleWord())
-      return VAL == RHS.VAL;
+      return U.VAL == RHS.U.VAL;
     return EqualSlowCase(RHS);
   }
 
@@ -974,7 +977,7 @@
   /// \returns true if *this == Val
   bool operator==(uint64_t Val) const {
     if (isSingleWord())
-      return VAL == Val;
+      return U.VAL == Val;
     return EqualSlowCase(Val);
   }
 
@@ -1206,11 +1209,11 @@
   /// \brief Set every bit to 1.
   void setAllBits() {
     if (isSingleWord())
-      VAL = UINT64_MAX;
+      U.VAL = UINT64_MAX;
     else {
       // Set all the bits in all the words.
       for (unsigned i = 0; i < getNumWords(); ++i)
-        pVal[i] = UINT64_MAX;
+        U.pVal[i] = UINT64_MAX;
     }
     // Clear the unused ones
     clearUnusedBits();
@@ -1227,9 +1230,9 @@
   /// \brief Set every bit to 0.
   void clearAllBits() {
     if (isSingleWord())
-      VAL = 0;
+      U.VAL = 0;
     else
-      memset(pVal, 0, getNumWords() * APINT_WORD_SIZE);
+      memset(U.pVal, 0, getNumWords() * APINT_WORD_SIZE);
   }
 
   /// \brief Set a given bit to 0.
@@ -1240,10 +1243,10 @@
   /// \brief Toggle every bit to its opposite value.
   void flipAllBits() {
     if (isSingleWord())
-      VAL ^= UINT64_MAX;
+      U.VAL ^= UINT64_MAX;
     else {
       for (unsigned i = 0; i < getNumWords(); ++i)
-        pVal[i] ^= UINT64_MAX;
+        U.pVal[i] ^= UINT64_MAX;
     }
     clearUnusedBits();
   }
@@ -1318,9 +1321,9 @@
   /// uint64_t. Otherwise an assertion will result.
   uint64_t getZExtValue() const {
     if (isSingleWord())
-      return VAL;
+      return U.VAL;
     assert(getActiveBits() <= 64 && "Too many bits for uint64_t");
-    return pVal[0];
+    return U.pVal[0];
   }
 
   /// \brief Get sign extended value
@@ -1330,10 +1333,10 @@
   /// int64_t. Otherwise an assertion will result.
   int64_t getSExtValue() const {
     if (isSingleWord())
-      return int64_t(VAL << (APINT_BITS_PER_WORD - BitWidth)) >>
+      return int64_t(U.VAL << (APINT_BITS_PER_WORD - BitWidth)) >>
              (APINT_BITS_PER_WORD - BitWidth);
     assert(getMinSignedBits() <= 64 && "Too many bits for int64_t");
-    return int64_t(pVal[0]);
+    return int64_t(U.pVal[0]);
   }
 
   /// \brief Get bits required for string value.
@@ -1353,7 +1356,7 @@
   unsigned countLeadingZeros() const {
     if (isSingleWord()) {
       unsigned unusedBits = APINT_BITS_PER_WORD - BitWidth;
-      return llvm::countLeadingZeros(VAL) - unusedBits;
+      return llvm::countLeadingZeros(U.VAL) - unusedBits;
     }
     return countLeadingZerosSlowCase();
   }
@@ -1394,7 +1397,7 @@
   /// of ones from the least significant bit to the first zero bit.
   unsigned countTrailingOnes() const {
     if (isSingleWord())
-      return llvm::countTrailingOnes(VAL);
+      return llvm::countTrailingOnes(U.VAL);
     return countTrailingOnesSlowCase();
   }
 
@@ -1406,7 +1409,7 @@
   /// \returns 0 if the value is zero, otherwise returns the number of set bits.
   unsigned countPopulation() const {
     if (isSingleWord())
-      return llvm::countPopulation(VAL);
+      return llvm::countPopulation(U.VAL);
     return countPopulationSlowCase();
   }
 
@@ -1465,7 +1468,7 @@
       uint64_t I;
       double D;
     } T;
-    T.I = (isSingleWord() ? VAL : pVal[0]);
+    T.I = (isSingleWord() ? U.VAL : U.pVal[0]);
     return T.D;
   }
 
@@ -1479,7 +1482,7 @@
       unsigned I;
       float F;
     } T;
-    T.I = unsigned((isSingleWord() ? VAL : pVal[0]));
+    T.I = unsigned((isSingleWord() ? U.VAL : U.pVal[0]));
     return T.F;
   }
 
@@ -1537,7 +1540,7 @@
     // get 0. If VAL is 0, we get UINT64_MAX which gets truncated to
     // UINT32_MAX.
     if (BitWidth == 1)
-      return VAL - 1;
+      return U.VAL - 1;
 
     // Handle the zero case.
     if (!getBoolValue())
Index: lib/IR/LLVMContextImpl.h
===================================================================
--- lib/IR/LLVMContextImpl.h
+++ lib/IR/LLVMContextImpl.h
@@ -52,12 +52,12 @@
 struct DenseMapAPIntKeyInfo {
   static inline APInt getEmptyKey() {
     APInt V(nullptr, 0);
-    V.VAL = 0;
+    V.U.VAL = 0;
     return V;
   }
   static inline APInt getTombstoneKey() {
     APInt V(nullptr, 0);
-    V.VAL = 1;
+    V.U.VAL = 1;
     return V;
   }
   static unsigned getHashValue(const APInt &Key) {
Index: lib/Support/APInt.cpp
===================================================================
--- lib/Support/APInt.cpp
+++ lib/Support/APInt.cpp
@@ -76,48 +76,48 @@
 
 
 void APInt::initSlowCase(uint64_t val, bool isSigned) {
-  pVal = getClearedMemory(getNumWords());
-  pVal[0] = val;
+  U.pVal = getClearedMemory(getNumWords());
+  U.pVal[0] = val;
   if (isSigned && int64_t(val) < 0)
     for (unsigned i = 1; i < getNumWords(); ++i)
-      pVal[i] = -1ULL;
+      U.pVal[i] = -1ULL;
   clearUnusedBits();
 }
 
 void APInt::initSlowCase(const APInt& that) {
-  pVal = getMemory(getNumWords());
-  memcpy(pVal, that.pVal, getNumWords() * APINT_WORD_SIZE);
+  U.pVal = getMemory(getNumWords());
+  memcpy(U.pVal, that.U.pVal, getNumWords() * APINT_WORD_SIZE);
 }
 
 void APInt::initFromArray(ArrayRef<uint64_t> bigVal) {
   assert(BitWidth && "Bitwidth too small");
   assert(bigVal.data() && "Null pointer detected!");
   if (isSingleWord())
-    VAL = bigVal[0];
+    U.VAL = bigVal[0];
   else {
     // Get memory, cleared to 0
-    pVal = getClearedMemory(getNumWords());
+    U.pVal = getClearedMemory(getNumWords());
     // Calculate the number of words to copy
     unsigned words = std::min<unsigned>(bigVal.size(), getNumWords());
     // Copy the words from bigVal to pVal
-    memcpy(pVal, bigVal.data(), words * APINT_WORD_SIZE);
+    memcpy(U.pVal, bigVal.data(), words * APINT_WORD_SIZE);
   }
   // Make sure unused high bits are cleared
   clearUnusedBits();
 }
 
 APInt::APInt(unsigned numBits, ArrayRef<uint64_t> bigVal)
-  : BitWidth(numBits), VAL(0) {
+  : BitWidth(numBits) {
   initFromArray(bigVal);
 }
 
 APInt::APInt(unsigned numBits, unsigned numWords, const uint64_t bigVal[])
-  : BitWidth(numBits), VAL(0) {
+  : BitWidth(numBits) {
   initFromArray(makeArrayRef(bigVal, numWords));
 }
 
 APInt::APInt(unsigned numbits, StringRef Str, uint8_t radix)
-  : BitWidth(numbits), VAL(0) {
+  : BitWidth(numbits) {
   assert(BitWidth && "Bitwidth too small");
   fromString(numbits, Str, radix);
 }
@@ -130,25 +130,24 @@
   if (BitWidth == RHS.getBitWidth()) {
     // assume same bit-width single-word case is already handled
     assert(!isSingleWord());
-    memcpy(pVal, RHS.pVal, getNumWords() * APINT_WORD_SIZE);
+    memcpy(U.pVal, RHS.U.pVal, getNumWords() * APINT_WORD_SIZE);
     return *this;
   }
 
   if (isSingleWord()) {
     // assume case where both are single words is already handled
     assert(!RHS.isSingleWord());
-    VAL = 0;
-    pVal = getMemory(RHS.getNumWords());
-    memcpy(pVal, RHS.pVal, RHS.getNumWords() * APINT_WORD_SIZE);
+    U.pVal = getMemory(RHS.getNumWords());
+    memcpy(U.pVal, RHS.U.pVal, RHS.getNumWords() * APINT_WORD_SIZE);
   } else if (getNumWords() == RHS.getNumWords())
-    memcpy(pVal, RHS.pVal, RHS.getNumWords() * APINT_WORD_SIZE);
+    memcpy(U.pVal, RHS.U.pVal, RHS.getNumWords() * APINT_WORD_SIZE);
   else if (RHS.isSingleWord()) {
-    delete [] pVal;
-    VAL = RHS.VAL;
+    delete [] U.pVal;
+    U.VAL = RHS.U.VAL;
   } else {
-    delete [] pVal;
-    pVal = getMemory(RHS.getNumWords());
-    memcpy(pVal, RHS.pVal, RHS.getNumWords() * APINT_WORD_SIZE);
+    delete [] U.pVal;
+    U.pVal = getMemory(RHS.getNumWords());
+    memcpy(U.pVal, RHS.U.pVal, RHS.getNumWords() * APINT_WORD_SIZE);
   }
   BitWidth = RHS.BitWidth;
   return clearUnusedBits();
@@ -156,10 +155,10 @@
 
 APInt& APInt::operator=(uint64_t RHS) {
   if (isSingleWord())
-    VAL = RHS;
+    U.VAL = RHS;
   else {
-    pVal[0] = RHS;
-    memset(pVal+1, 0, (getNumWords() - 1) * APINT_WORD_SIZE);
+    U.pVal[0] = RHS;
+    memset(U.pVal+1, 0, (getNumWords() - 1) * APINT_WORD_SIZE);
   }
   return clearUnusedBits();
 }
@@ -169,13 +168,13 @@
   ID.AddInteger(BitWidth);
 
   if (isSingleWord()) {
-    ID.AddInteger(VAL);
+    ID.AddInteger(U.VAL);
     return;
   }
 
   unsigned NumWords = getNumWords();
   for (unsigned i = 0; i < NumWords; ++i)
-    ID.AddInteger(pVal[i]);
+    ID.AddInteger(U.pVal[i]);
 }
 
 /// This function adds a single "digit" integer, y, to the multiple
@@ -198,9 +197,9 @@
 /// @brief Prefix increment operator. Increments the APInt by one.
 APInt& APInt::operator++() {
   if (isSingleWord())
-    ++VAL;
+    ++U.VAL;
   else
-    add_1(pVal, pVal, getNumWords(), 1);
+    add_1(U.pVal, U.pVal, getNumWords(), 1);
   return clearUnusedBits();
 }
 
@@ -227,9 +226,9 @@
 /// @brief Prefix decrement operator. Decrements the APInt by one.
 APInt& APInt::operator--() {
   if (isSingleWord())
-    --VAL;
+    --U.VAL;
   else
-    sub_1(pVal, getNumWords(), 1);
+    sub_1(U.pVal, getNumWords(), 1);
   return clearUnusedBits();
 }
 
@@ -254,18 +253,18 @@
 APInt& APInt::operator+=(const APInt& RHS) {
   assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
   if (isSingleWord())
-    VAL += RHS.VAL;
+    U.VAL += RHS.U.VAL;
   else {
-    add(pVal, pVal, RHS.pVal, getNumWords());
+    add(U.pVal, U.pVal, RHS.U.pVal, getNumWords());
   }
   return clearUnusedBits();
 }
 
 APInt& APInt::operator+=(uint64_t RHS) {
   if (isSingleWord())
-    VAL += RHS;
+    U.VAL += RHS;
   else
-    add_1(pVal, pVal, getNumWords(), RHS);
+    add_1(U.pVal, U.pVal, getNumWords(), RHS);
   return clearUnusedBits();
 }
 
@@ -289,17 +288,17 @@
 APInt& APInt::operator-=(const APInt& RHS) {
   assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
   if (isSingleWord())
-    VAL -= RHS.VAL;
+    U.VAL -= RHS.U.VAL;
   else
-    sub(pVal, pVal, RHS.pVal, getNumWords());
+    sub(U.pVal, U.pVal, RHS.U.pVal, getNumWords());
   return clearUnusedBits();
 }
 
 APInt& APInt::operator-=(uint64_t RHS) {
   if (isSingleWord())
-    VAL -= RHS;
+    U.VAL -= RHS;
   else
-    sub_1(pVal, getNumWords(), RHS);
+    sub_1(U.pVal, getNumWords(), RHS);
   return clearUnusedBits();
 }
 
@@ -374,7 +373,7 @@
 APInt& APInt::operator*=(const APInt& RHS) {
   assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
   if (isSingleWord()) {
-    VAL *= RHS.VAL;
+    U.VAL *= RHS.U.VAL;
     clearUnusedBits();
     return *this;
   }
@@ -400,12 +399,12 @@
   uint64_t *dest = getMemory(destWords);
 
   // Perform the long multiply
-  mul(dest, pVal, lhsWords, RHS.pVal, rhsWords);
+  mul(dest, U.pVal, lhsWords, RHS.U.pVal, rhsWords);
 
   // Copy result back into *this
   clearAllBits();
   unsigned wordsToCopy = destWords >= getNumWords() ? getNumWords() : destWords;
-  memcpy(pVal, dest, wordsToCopy * APINT_WORD_SIZE);
+  memcpy(U.pVal, dest, wordsToCopy * APINT_WORD_SIZE);
   clearUnusedBits();
 
   // delete dest array and return
@@ -416,48 +415,48 @@
 APInt& APInt::operator&=(const APInt& RHS) {
   assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
   if (isSingleWord()) {
-    VAL &= RHS.VAL;
+    U.VAL &= RHS.U.VAL;
     return *this;
   }
   unsigned numWords = getNumWords();
   for (unsigned i = 0; i < numWords; ++i)
-    pVal[i] &= RHS.pVal[i];
+    U.pVal[i] &= RHS.U.pVal[i];
   return *this;
 }
 
 APInt &APInt::operator&=(uint64_t RHS) {
   if (isSingleWord()) {
-    VAL &= RHS;
+    U.VAL &= RHS;
     return *this;
   }
-  pVal[0] &= RHS;
+  U.pVal[0] &= RHS;
   unsigned numWords = getNumWords();
   for (unsigned i = 1; i < numWords; ++i)
-    pVal[i] = 0;
+    U.pVal[i] = 0;
   return *this;
 }
 
 APInt& APInt::operator|=(const APInt& RHS) {
   assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
   if (isSingleWord()) {
-    VAL |= RHS.VAL;
+    U.VAL |= RHS.U.VAL;
     return *this;
   }
   unsigned numWords = getNumWords();
   for (unsigned i = 0; i < numWords; ++i)
-    pVal[i] |= RHS.pVal[i];
+    U.pVal[i] |= RHS.U.pVal[i];
   return *this;
 }
 
 APInt& APInt::operator^=(const APInt& RHS) {
   assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
   if (isSingleWord()) {
-    VAL ^= RHS.VAL;
+    U.VAL ^= RHS.U.VAL;
     return *this;
   }
   unsigned numWords = getNumWords();
   for (unsigned i = 0; i < numWords; ++i)
-    pVal[i] ^= RHS.pVal[i];
+    U.pVal[i] ^= RHS.U.pVal[i];
   return *this;
 }
 
@@ -465,7 +464,7 @@
   unsigned numWords = getNumWords();
   uint64_t* val = getMemory(numWords);
   for (unsigned i = 0; i < numWords; ++i)
-    val[i] = pVal[i] & RHS.pVal[i];
+    val[i] = U.pVal[i] & RHS.U.pVal[i];
   return APInt(val, getBitWidth());
 }
 
@@ -473,7 +472,7 @@
   unsigned numWords = getNumWords();
   uint64_t *val = getMemory(numWords);
   for (unsigned i = 0; i < numWords; ++i)
-    val[i] = pVal[i] | RHS.pVal[i];
+    val[i] = U.pVal[i] | RHS.U.pVal[i];
   return APInt(val, getBitWidth());
 }
 
@@ -481,7 +480,7 @@
   unsigned numWords = getNumWords();
   uint64_t *val = getMemory(numWords);
   for (unsigned i = 0; i < numWords; ++i)
-    val[i] = pVal[i] ^ RHS.pVal[i];
+    val[i] = U.pVal[i] ^ RHS.U.pVal[i];
 
   return APInt(val, getBitWidth());
 }
@@ -489,20 +488,20 @@
 APInt APInt::operator*(const APInt& RHS) const {
   assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
   if (isSingleWord())
-    return APInt(BitWidth, VAL * RHS.VAL);
+    return APInt(BitWidth, U.VAL * RHS.U.VAL);
   APInt Result(*this);
   Result *= RHS;
   return Result;
 }
 
 bool APInt::EqualSlowCase(const APInt& RHS) const {
-  return std::equal(pVal, pVal + getNumWords(), RHS.pVal);
+  return std::equal(U.pVal, U.pVal + getNumWords(), RHS.U.pVal);
 }
 
 bool APInt::EqualSlowCase(uint64_t Val) const {
   unsigned n = getActiveBits();
   if (n <= APINT_BITS_PER_WORD)
-    return pVal[0] == Val;
+    return U.pVal[0] == Val;
   else
     return false;
 }
@@ -510,7 +509,7 @@
 bool APInt::ult(const APInt& RHS) const {
   assert(BitWidth == RHS.BitWidth && "Bit widths must be same for comparison");
   if (isSingleWord())
-    return VAL < RHS.VAL;
+    return U.VAL < RHS.U.VAL;
 
   // Get active bit length of both operands
   unsigned n1 = getActiveBits();
@@ -526,14 +525,14 @@
 
   // If they bot fit in a word, just compare the low order word
   if (n1 <= APINT_BITS_PER_WORD && n2 <= APINT_BITS_PER_WORD)
-    return pVal[0] < RHS.pVal[0];
+    return U.pVal[0] < RHS.U.pVal[0];
 
   // Otherwise, compare all words
   unsigned topWord = whichWord(std::max(n1,n2)-1);
   for (int i = topWord; i >= 0; --i) {
-    if (pVal[i] > RHS.pVal[i])
+    if (U.pVal[i] > RHS.U.pVal[i])
       return false;
-    if (pVal[i] < RHS.pVal[i])
+    if (U.pVal[i] < RHS.U.pVal[i])
       return true;
   }
   return false;
@@ -542,8 +541,8 @@
 bool APInt::slt(const APInt& RHS) const {
   assert(BitWidth == RHS.BitWidth && "Bit widths must be same for comparison");
   if (isSingleWord()) {
-    int64_t lhsSext = SignExtend64(VAL, BitWidth);
-    int64_t rhsSext = SignExtend64(RHS.VAL, BitWidth);
+    int64_t lhsSext = SignExtend64(U.VAL, BitWidth);
+    int64_t rhsSext = SignExtend64(RHS.U.VAL, BitWidth);
     return lhsSext < rhsSext;
   }
 
@@ -561,9 +560,9 @@
 
 void APInt::setBit(unsigned bitPosition) {
   if (isSingleWord())
-    VAL |= maskBit(bitPosition);
+    U.VAL |= maskBit(bitPosition);
   else
-    pVal[whichWord(bitPosition)] |= maskBit(bitPosition);
+    U.pVal[whichWord(bitPosition)] |= maskBit(bitPosition);
 }
 
 void APInt::setBits(unsigned loBit, unsigned hiBit) {
@@ -584,17 +583,17 @@
       uint64_t mask = UINT64_MAX;
       mask >>= (APINT_BITS_PER_WORD - (hiBit - loBit));
       mask <<= whichBit(loBit);
-      pVal[loWord] |= mask;
+      U.pVal[loWord] |= mask;
     } else {
       // Set bits span multiple words, create a lo mask with set bits starting
       // at loBit, a hi mask with set bits below hiBit and set all bits of the
       // words in between.
       uint64_t loMask = UINT64_MAX << whichBit(loBit);
       uint64_t hiMask = UINT64_MAX >> (64 - whichBit(hiBit1) - 1);
-      pVal[loWord] |= loMask;
-      pVal[hiWord] |= hiMask;
+      U.pVal[loWord] |= loMask;
+      U.pVal[hiWord] |= hiMask;
       for (unsigned word = loWord + 1; word < hiWord; ++word)
-        pVal[word] = UINT64_MAX;
+        U.pVal[word] = UINT64_MAX;
     }
   }
 }
@@ -603,9 +602,9 @@
 /// @brief Set a given bit to 0.
 void APInt::clearBit(unsigned bitPosition) {
   if (isSingleWord())
-    VAL &= ~maskBit(bitPosition);
+    U.VAL &= ~maskBit(bitPosition);
   else
-    pVal[whichWord(bitPosition)] &= ~maskBit(bitPosition);
+    U.pVal[whichWord(bitPosition)] &= ~maskBit(bitPosition);
 }
 
 /// @brief Toggle every bit to its opposite value.
@@ -625,7 +624,7 @@
          "Illegal bit extraction");
 
   if (isSingleWord())
-    return APInt(numBits, VAL >> bitPosition);
+    return APInt(numBits, U.VAL >> bitPosition);
 
   unsigned loBit = whichBit(bitPosition);
   unsigned loWord = whichWord(bitPosition);
@@ -633,12 +632,12 @@
 
   // Single word result extracting bits from a single word source.
   if (loWord == hiWord)
-    return APInt(numBits, pVal[loWord] >> loBit);
+    return APInt(numBits, U.pVal[loWord] >> loBit);
 
   // Extracting bits that start on a source word boundary can be done
   // as a fast memory copy.
   if (loBit == 0)
-    return APInt(numBits, makeArrayRef(pVal + loWord, 1 + hiWord - loWord));
+    return APInt(numBits, makeArrayRef(U.pVal + loWord, 1 + hiWord - loWord));
 
   // General case - shift + copy source words directly into place.
   APInt Result(numBits, 0);
@@ -646,10 +645,10 @@
   unsigned NumDstWords = Result.getNumWords();
 
   for (unsigned word = 0; word < NumDstWords; ++word) {
-    uint64_t w0 = pVal[loWord + word];
+    uint64_t w0 = U.pVal[loWord + word];
     uint64_t w1 =
-        (loWord + word + 1) < NumSrcWords ? pVal[loWord + word + 1] : 0;
-    Result.pVal[word] = (w0 >> loBit) | (w1 << (APINT_BITS_PER_WORD - loBit));
+        (loWord + word + 1) < NumSrcWords ? U.pVal[loWord + word + 1] : 0;
+    Result.U.pVal[word] = (w0 >> loBit) | (w1 << (APINT_BITS_PER_WORD - loBit));
   }
 
   return Result.clearUnusedBits();
@@ -710,9 +709,9 @@
 
 hash_code llvm::hash_value(const APInt &Arg) {
   if (Arg.isSingleWord())
-    return hash_combine(Arg.VAL);
+    return hash_combine(Arg.U.VAL);
 
-  return hash_combine_range(Arg.pVal, Arg.pVal + Arg.getNumWords());
+  return hash_combine_range(Arg.U.pVal, Arg.U.pVal + Arg.getNumWords());
 }
 
 bool APInt::isSplat(unsigned SplatSizeInBits) const {
@@ -737,7 +736,7 @@
 unsigned APInt::countLeadingZerosSlowCase() const {
   unsigned Count = 0;
   for (int i = getNumWords()-1; i >= 0; --i) {
-    integerPart V = pVal[i];
+    integerPart V = U.pVal[i];
     if (V == 0)
       Count += APINT_BITS_PER_WORD;
     else {
@@ -753,7 +752,7 @@
 
 unsigned APInt::countLeadingOnes() const {
   if (isSingleWord())
-    return llvm::countLeadingOnes(VAL << (APINT_BITS_PER_WORD - BitWidth));
+    return llvm::countLeadingOnes(U.VAL << (APINT_BITS_PER_WORD - BitWidth));
 
   unsigned highWordBits = BitWidth % APINT_BITS_PER_WORD;
   unsigned shift;
@@ -764,13 +763,13 @@
     shift = APINT_BITS_PER_WORD - highWordBits;
   }
   int i = getNumWords() - 1;
-  unsigned Count = llvm::countLeadingOnes(pVal[i] << shift);
+  unsigned Count = llvm::countLeadingOnes(U.pVal[i] << shift);
   if (Count == highWordBits) {
     for (i--; i >= 0; --i) {
-      if (pVal[i] == -1ULL)
+      if (U.pVal[i] == -1ULL)
         Count += APINT_BITS_PER_WORD;
       else {
-        Count += llvm::countLeadingOnes(pVal[i]);
+        Count += llvm::countLeadingOnes(U.pVal[i]);
         break;
       }
     }
@@ -780,30 +779,30 @@
 
 unsigned APInt::countTrailingZeros() const {
   if (isSingleWord())
-    return std::min(unsigned(llvm::countTrailingZeros(VAL)), BitWidth);
+    return std::min(unsigned(llvm::countTrailingZeros(U.VAL)), BitWidth);
   unsigned Count = 0;
   unsigned i = 0;
-  for (; i < getNumWords() && pVal[i] == 0; ++i)
+  for (; i < getNumWords() && U.pVal[i] == 0; ++i)
     Count += APINT_BITS_PER_WORD;
   if (i < getNumWords())
-    Count += llvm::countTrailingZeros(pVal[i]);
+    Count += llvm::countTrailingZeros(U.pVal[i]);
   return std::min(Count, BitWidth);
 }
 
 unsigned APInt::countTrailingOnesSlowCase() const {
   unsigned Count = 0;
   unsigned i = 0;
-  for (; i < getNumWords() && pVal[i] == -1ULL; ++i)
+  for (; i < getNumWords() && U.pVal[i] == -1ULL; ++i)
     Count += APINT_BITS_PER_WORD;
   if (i < getNumWords())
-    Count += llvm::countTrailingOnes(pVal[i]);
+    Count += llvm::countTrailingOnes(U.pVal[i]);
   return std::min(Count, BitWidth);
 }
 
 unsigned APInt::countPopulationSlowCase() const {
   unsigned Count = 0;
   for (unsigned i = 0; i < getNumWords(); ++i)
-    Count += llvm::countPopulation(pVal[i]);
+    Count += llvm::countPopulation(U.pVal[i]);
   return Count;
 }
 
@@ -822,24 +821,24 @@
 APInt APInt::byteSwap() const {
   assert(BitWidth >= 16 && BitWidth % 16 == 0 && "Cannot byteswap!");
   if (BitWidth == 16)
-    return APInt(BitWidth, ByteSwap_16(uint16_t(VAL)));
+    return APInt(BitWidth, ByteSwap_16(uint16_t(U.VAL)));
   if (BitWidth == 32)
-    return APInt(BitWidth, ByteSwap_32(unsigned(VAL)));
+    return APInt(BitWidth, ByteSwap_32(unsigned(U.VAL)));
   if (BitWidth == 48) {
-    unsigned Tmp1 = unsigned(VAL >> 16);
+    unsigned Tmp1 = unsigned(U.VAL >> 16);
     Tmp1 = ByteSwap_32(Tmp1);
-    uint16_t Tmp2 = uint16_t(VAL);
+    uint16_t Tmp2 = uint16_t(U.VAL);
     Tmp2 = ByteSwap_16(Tmp2);
     return APInt(BitWidth, (uint64_t(Tmp2) << 32) | Tmp1);
   }
   if (BitWidth == 64)
-    return APInt(BitWidth, ByteSwap_64(VAL));
+    return APInt(BitWidth, ByteSwap_64(U.VAL));
 
   APInt Result(getNumWords() * APINT_BITS_PER_WORD, 0);
   for (unsigned I = 0, N = getNumWords(); I != N; ++I)
-    Result.pVal[I] = ByteSwap_64(pVal[N - I - 1]);
+    Result.U.pVal[I] = ByteSwap_64(U.pVal[N - I - 1]);
   if (Result.BitWidth != BitWidth) {
-    lshrNear(Result.pVal, Result.pVal, getNumWords(),
+    lshrNear(Result.U.pVal, Result.U.pVal, getNumWords(),
              Result.BitWidth - BitWidth);
     Result.BitWidth = BitWidth;
   }
@@ -849,13 +848,13 @@
 APInt APInt::reverseBits() const {
   switch (BitWidth) {
   case 64:
-    return APInt(BitWidth, llvm::reverseBits<uint64_t>(VAL));
+    return APInt(BitWidth, llvm::reverseBits<uint64_t>(U.VAL));
   case 32:
-    return APInt(BitWidth, llvm::reverseBits<uint32_t>(VAL));
+    return APInt(BitWidth, llvm::reverseBits<uint32_t>(U.VAL));
   case 16:
-    return APInt(BitWidth, llvm::reverseBits<uint16_t>(VAL));
+    return APInt(BitWidth, llvm::reverseBits<uint16_t>(U.VAL));
   case 8:
-    return APInt(BitWidth, llvm::reverseBits<uint8_t>(VAL));
+    return APInt(BitWidth, llvm::reverseBits<uint8_t>(U.VAL));
   default:
     break;
   }
@@ -970,13 +969,13 @@
   uint64_t mantissa;
   unsigned hiWord = whichWord(n-1);
   if (hiWord == 0) {
-    mantissa = Tmp.pVal[0];
+    mantissa = Tmp.U.pVal[0];
     if (n > 52)
       mantissa >>= n - 52; // shift down, we want the top 52 bits.
   } else {
     assert(hiWord > 0 && "huh?");
-    uint64_t hibits = Tmp.pVal[hiWord] << (52 - n % APINT_BITS_PER_WORD);
-    uint64_t lobits = Tmp.pVal[hiWord-1] >> (11 + n % APINT_BITS_PER_WORD);
+    uint64_t hibits = Tmp.U.pVal[hiWord] << (52 - n % APINT_BITS_PER_WORD);
+    uint64_t lobits = Tmp.U.pVal[hiWord-1] >> (11 + n % APINT_BITS_PER_WORD);
     mantissa = hibits | lobits;
   }
 
@@ -1003,12 +1002,12 @@
   // Copy full words.
   unsigned i;
   for (i = 0; i != width / APINT_BITS_PER_WORD; i++)
-    Result.pVal[i] = pVal[i];
+    Result.U.pVal[i] = U.pVal[i];
 
   // Truncate and copy any partial word.
   unsigned bits = (0 - width) % APINT_BITS_PER_WORD;
   if (bits != 0)
-    Result.pVal[i] = pVal[i] << bits >> bits;
+    Result.U.pVal[i] = U.pVal[i] << bits >> bits;
 
   return Result;
 }
@@ -1018,7 +1017,7 @@
   assert(width > BitWidth && "Invalid APInt SignExtend request");
 
   if (width <= APINT_BITS_PER_WORD) {
-    uint64_t val = VAL << (APINT_BITS_PER_WORD - BitWidth);
+    uint64_t val = U.VAL << (APINT_BITS_PER_WORD - BitWidth);
     val = (int64_t)val >> (width - BitWidth);
     return APInt(width, val >> (APINT_BITS_PER_WORD - width));
   }
@@ -1030,7 +1029,7 @@
   uint64_t word = 0;
   for (i = 0; i != BitWidth / APINT_BITS_PER_WORD; i++) {
     word = getRawData()[i];
-    Result.pVal[i] = word;
+    Result.U.pVal[i] = word;
   }
 
   // Read and sign-extend any partial word.
@@ -1042,14 +1041,14 @@
 
   // Write remaining full words.
   for (; i != width / APINT_BITS_PER_WORD; i++) {
-    Result.pVal[i] = word;
+    Result.U.pVal[i] = word;
     word = (int64_t)word >> (APINT_BITS_PER_WORD - 1);
   }
 
   // Write any partial word.
   bits = (0 - width) % APINT_BITS_PER_WORD;
   if (bits != 0)
-    Result.pVal[i] = word << bits >> bits;
+    Result.U.pVal[i] = word << bits >> bits;
 
   return Result;
 }
@@ -1059,17 +1058,17 @@
   assert(width > BitWidth && "Invalid APInt ZeroExtend request");
 
   if (width <= APINT_BITS_PER_WORD)
-    return APInt(width, VAL);
+    return APInt(width, U.VAL);
 
   APInt Result(getMemory(getNumWords(width)), width);
 
   // Copy words.
   unsigned i;
   for (i = 0; i != getNumWords(); i++)
-    Result.pVal[i] = getRawData()[i];
+    Result.U.pVal[i] = getRawData()[i];
 
   // Zero remaining words.
-  memset(&Result.pVal[i], 0, (Result.getNumWords() - i) * APINT_WORD_SIZE);
+  memset(&Result.U.pVal[i], 0, (Result.getNumWords() - i) * APINT_WORD_SIZE);
 
   return Result;
 }
@@ -1120,7 +1119,7 @@
   if (isSingleWord()) {
     if (shiftAmt == BitWidth)
       return APInt(BitWidth, 0); // undefined
-    return APInt(BitWidth, SignExtend64(VAL, BitWidth) >> shiftAmt);
+    return APInt(BitWidth, SignExtend64(U.VAL, BitWidth) >> shiftAmt);
   }
 
   // If all the bits were shifted out, the result is, technically, undefined.
@@ -1148,7 +1147,7 @@
   if (wordShift == 0) {
     // Move the words containing significant bits
     for (unsigned i = 0; i <= breakWord; ++i)
-      val[i] = pVal[i+offset]; // move whole word
+      val[i] = U.pVal[i+offset]; // move whole word
 
     // Adjust the top significant word for sign bit fill, if negative
     if (isNegative())
@@ -1159,13 +1158,13 @@
     for (unsigned i = 0; i < breakWord; ++i) {
       // This combines the shifted corresponding word with the low bits from
       // the next word (shifted into this word's high bits).
-      val[i] = (pVal[i+offset] >> wordShift) |
-               (pVal[i+offset+1] << (APINT_BITS_PER_WORD - wordShift));
+      val[i] = (U.pVal[i+offset] >> wordShift) |
+               (U.pVal[i+offset+1] << (APINT_BITS_PER_WORD - wordShift));
     }
 
     // Shift the break word. In this case there are no bits from the next word
     // to include in this word.
-    val[breakWord] = pVal[breakWord+offset] >> wordShift;
+    val[breakWord] = U.pVal[breakWord+offset] >> wordShift;
 
     // Deal with sign extension in the break word, and possibly the word before
     // it.
@@ -1202,7 +1201,7 @@
     if (shiftAmt >= BitWidth)
       return APInt(BitWidth, 0);
     else
-      return APInt(BitWidth, this->VAL >> shiftAmt);
+      return APInt(BitWidth, this->U.VAL >> shiftAmt);
   }
 
   // If all the bits were shifted out, the result is 0. This avoids issues
@@ -1222,7 +1221,7 @@
 
   // If we are shifting less than a word, compute the shift with a simple carry
   if (shiftAmt < APINT_BITS_PER_WORD) {
-    lshrNear(val, pVal, getNumWords(), shiftAmt);
+    lshrNear(val, U.pVal, getNumWords(), shiftAmt);
     APInt Result(val, BitWidth);
     Result.clearUnusedBits();
     return Result;
@@ -1235,7 +1234,7 @@
   // If we are shifting whole words, just move whole words
   if (wordShift == 0) {
     for (unsigned i = 0; i < getNumWords() - offset; ++i)
-      val[i] = pVal[i+offset];
+      val[i] = U.pVal[i+offset];
     for (unsigned i = getNumWords()-offset; i < getNumWords(); i++)
       val[i] = 0;
     APInt Result(val, BitWidth);
@@ -1246,10 +1245,10 @@
   // Shift the low order words
   unsigned breakWord = getNumWords() - offset -1;
   for (unsigned i = 0; i < breakWord; ++i)
-    val[i] = (pVal[i+offset] >> wordShift) |
-             (pVal[i+offset+1] << (APINT_BITS_PER_WORD - wordShift));
+    val[i] = (U.pVal[i+offset] >> wordShift) |
+             (U.pVal[i+offset+1] << (APINT_BITS_PER_WORD - wordShift));
   // Shift the break word.
-  val[breakWord] = pVal[breakWord+offset] >> wordShift;
+  val[breakWord] = U.pVal[breakWord+offset] >> wordShift;
 
   // Remaining words are 0
   for (unsigned i = breakWord+1; i < getNumWords(); ++i)
@@ -1286,8 +1285,8 @@
   if (shiftAmt < APINT_BITS_PER_WORD) {
     uint64_t carry = 0;
     for (unsigned i = 0; i < getNumWords(); i++) {
-      val[i] = pVal[i] << shiftAmt | carry;
-      carry = pVal[i] >> (APINT_BITS_PER_WORD - shiftAmt);
+      val[i] = U.pVal[i] << shiftAmt | carry;
+      carry = U.pVal[i] >> (APINT_BITS_PER_WORD - shiftAmt);
     }
     APInt Result(val, BitWidth);
     Result.clearUnusedBits();
@@ -1303,7 +1302,7 @@
     for (unsigned i = 0; i < offset; i++)
       val[i] = 0;
     for (unsigned i = offset; i < getNumWords(); i++)
-      val[i] = pVal[i-offset];
+      val[i] = U.pVal[i-offset];
     APInt Result(val, BitWidth);
     Result.clearUnusedBits();
     return Result;
@@ -1312,9 +1311,9 @@
   // Copy whole words from this to Result.
   unsigned i = getNumWords() - 1;
   for (; i > offset; --i)
-    val[i] = pVal[i-offset] << wordShift |
-             pVal[i-offset-1] >> (APINT_BITS_PER_WORD - wordShift);
-  val[offset] = pVal[0] << wordShift;
+    val[i] = U.pVal[i-offset] << wordShift |
+             U.pVal[i-offset-1] >> (APINT_BITS_PER_WORD - wordShift);
+  val[offset] = U.pVal[0] << wordShift;
   for (i = 0; i < offset; ++i)
     val[i] = 0;
   APInt Result(val, BitWidth);
@@ -1381,7 +1380,7 @@
       /* 21-30 */ 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
       /*    31 */ 6
     };
-    return APInt(BitWidth, results[ (isSingleWord() ? VAL : pVal[0]) ]);
+    return APInt(BitWidth, results[ (isSingleWord() ? U.VAL : U.pVal[0]) ]);
   }
 
   // If the magnitude of the value fits in less than 52 bits (the precision of
@@ -1390,7 +1389,8 @@
   // This should be faster than the algorithm below.
   if (magnitude < 52) {
     return APInt(BitWidth,
-                 uint64_t(::round(::sqrt(double(isSingleWord()?VAL:pVal[0])))));
+                 uint64_t(::round(::sqrt(double(isSingleWord() ? U.VAL
+                                                               : U.pVal[0])))));
   }
 
   // Okay, all the short cuts are exhausted. We must compute it. The following
@@ -1768,7 +1768,7 @@
   // Initialize the dividend
   memset(U, 0, (m+n+1)*sizeof(unsigned));
   for (unsigned i = 0; i < lhsWords; ++i) {
-    uint64_t tmp = (LHS.getNumWords() == 1 ? LHS.VAL : LHS.pVal[i]);
+    uint64_t tmp = (LHS.getNumWords() == 1 ? LHS.U.VAL : LHS.U.pVal[i]);
     U[i * 2] = (unsigned)(tmp & mask);
     U[i * 2 + 1] = (unsigned)(tmp >> (sizeof(unsigned)*CHAR_BIT));
   }
@@ -1777,7 +1777,7 @@
   // Initialize the divisor
   memset(V, 0, (n)*sizeof(unsigned));
   for (unsigned i = 0; i < rhsWords; ++i) {
-    uint64_t tmp = (RHS.getNumWords() == 1 ? RHS.VAL : RHS.pVal[i]);
+    uint64_t tmp = (RHS.getNumWords() == 1 ? RHS.U.VAL : RHS.U.pVal[i]);
     V[i * 2] = (unsigned)(tmp & mask);
     V[i * 2 + 1] = (unsigned)(tmp >> (sizeof(unsigned)*CHAR_BIT));
   }
@@ -1837,12 +1837,12 @@
     // Set up the Quotient value's memory.
     if (Quotient->BitWidth != LHS.BitWidth) {
       if (Quotient->isSingleWord())
-        Quotient->VAL = 0;
+        Quotient->U.VAL = 0;
       else
-        delete [] Quotient->pVal;
+        delete [] Quotient->U.pVal;
       Quotient->BitWidth = LHS.BitWidth;
       if (!Quotient->isSingleWord())
-        Quotient->pVal = getClearedMemory(Quotient->getNumWords());
+        Quotient->U.pVal = getClearedMemory(Quotient->getNumWords());
     } else
       Quotient->clearAllBits();
 
@@ -1854,13 +1854,13 @@
       uint64_t tmp =
         uint64_t(Q[0]) | (uint64_t(Q[1]) << (APINT_BITS_PER_WORD / 2));
       if (Quotient->isSingleWord())
-        Quotient->VAL = tmp;
+        Quotient->U.VAL = tmp;
       else
-        Quotient->pVal[0] = tmp;
+        Quotient->U.pVal[0] = tmp;
     } else {
       assert(!Quotient->isSingleWord() && "Quotient APInt not large enough");
       for (unsigned i = 0; i < lhsWords; ++i)
-        Quotient->pVal[i] =
+        Quotient->U.pVal[i] =
           uint64_t(Q[i*2]) | (uint64_t(Q[i*2+1]) << (APINT_BITS_PER_WORD / 2));
     }
   }
@@ -1870,12 +1870,12 @@
     // Set up the Remainder value's memory.
     if (Remainder->BitWidth != RHS.BitWidth) {
       if (Remainder->isSingleWord())
-        Remainder->VAL = 0;
+        Remainder->U.VAL = 0;
       else
-        delete [] Remainder->pVal;
+        delete [] Remainder->U.pVal;
       Remainder->BitWidth = RHS.BitWidth;
       if (!Remainder->isSingleWord())
-        Remainder->pVal = getClearedMemory(Remainder->getNumWords());
+        Remainder->U.pVal = getClearedMemory(Remainder->getNumWords());
     } else
       Remainder->clearAllBits();
 
@@ -1885,13 +1885,13 @@
       uint64_t tmp =
         uint64_t(R[0]) | (uint64_t(R[1]) << (APINT_BITS_PER_WORD / 2));
       if (Remainder->isSingleWord())
-        Remainder->VAL = tmp;
+        Remainder->U.VAL = tmp;
       else
-        Remainder->pVal[0] = tmp;
+        Remainder->U.pVal[0] = tmp;
     } else {
       assert(!Remainder->isSingleWord() && "Remainder APInt not large enough");
       for (unsigned i = 0; i < rhsWords; ++i)
-        Remainder->pVal[i] =
+        Remainder->U.pVal[i] =
           uint64_t(R[i*2]) | (uint64_t(R[i*2+1]) << (APINT_BITS_PER_WORD / 2));
     }
   }
@@ -1910,8 +1910,8 @@
 
   // First, deal with the easy case
   if (isSingleWord()) {
-    assert(RHS.VAL != 0 && "Divide by zero?");
-    return APInt(BitWidth, VAL / RHS.VAL);
+    assert(RHS.U.VAL != 0 && "Divide by zero?");
+    return APInt(BitWidth, U.VAL / RHS.U.VAL);
   }
 
   // Get some facts about the LHS and RHS number of bits and words
@@ -1933,7 +1933,7 @@
     return APInt(BitWidth, 1);
   } else if (lhsWords == 1 && rhsWords == 1) {
     // All high words are zero, just use native divide
-    return APInt(BitWidth, this->pVal[0] / RHS.pVal[0]);
+    return APInt(BitWidth, this->U.pVal[0] / RHS.U.pVal[0]);
   }
 
   // We have to compute it the hard way. Invoke the Knuth divide algorithm.
@@ -1956,8 +1956,8 @@
 APInt APInt::urem(const APInt& RHS) const {
   assert(BitWidth == RHS.BitWidth && "Bit widths must be the same");
   if (isSingleWord()) {
-    assert(RHS.VAL != 0 && "Remainder by zero?");
-    return APInt(BitWidth, VAL % RHS.VAL);
+    assert(RHS.U.VAL != 0 && "Remainder by zero?");
+    return APInt(BitWidth, U.VAL % RHS.U.VAL);
   }
 
   // Get some facts about the LHS
@@ -1981,7 +1981,7 @@
     return APInt(BitWidth, 0);
   } else if (lhsWords == 1) {
     // All high words are zero, just use native remainder
-    return APInt(BitWidth, pVal[0] % RHS.pVal[0]);
+    return APInt(BitWidth, U.pVal[0] % RHS.U.pVal[0]);
   }
 
   // We have to compute it the hard way. Invoke the Knuth divide algorithm.
@@ -2007,9 +2007,9 @@
 
   // First, deal with the easy case
   if (LHS.isSingleWord()) {
-    assert(RHS.VAL != 0 && "Divide by zero?");
-    uint64_t QuotVal = LHS.VAL / RHS.VAL;
-    uint64_t RemVal = LHS.VAL % RHS.VAL;
+    assert(RHS.U.VAL != 0 && "Divide by zero?");
+    uint64_t QuotVal = LHS.U.VAL / RHS.U.VAL;
+    uint64_t RemVal = LHS.U.VAL % RHS.U.VAL;
     Quotient = APInt(LHS.BitWidth, QuotVal);
     Remainder = APInt(LHS.BitWidth, RemVal);
     return;
@@ -2042,8 +2042,8 @@
 
   if (lhsWords == 1 && rhsWords == 1) {
     // There is only one word to consider so use the native versions.
-    uint64_t lhsValue = LHS.isSingleWord() ? LHS.VAL : LHS.pVal[0];
-    uint64_t rhsValue = RHS.isSingleWord() ? RHS.VAL : RHS.pVal[0];
+    uint64_t lhsValue = LHS.isSingleWord() ? LHS.U.VAL : LHS.U.pVal[0];
+    uint64_t rhsValue = RHS.isSingleWord() ? RHS.U.VAL : RHS.U.pVal[0];
     Quotient = APInt(LHS.getBitWidth(), lhsValue / rhsValue);
     Remainder = APInt(LHS.getBitWidth(), lhsValue % rhsValue);
     return;
@@ -2170,9 +2170,11 @@
   assert((((slen-1)*64)/22 <= numbits || radix != 10) &&
          "Insufficient bit width");
 
-  // Allocate memory
-  if (!isSingleWord())
-    pVal = getClearedMemory(getNumWords());
+  // Allocate memory if needed
+  if (isSingleWord())
+    U.VAL = 0;
+  else
+    U.pVal = getClearedMemory(getNumWords());
 
   // Figure out if we can shift instead of multiply
   unsigned shift = (radix == 16 ? 4 : radix == 8 ? 3 : radix == 2 ? 1 : 0);
@@ -2197,9 +2199,9 @@
 
     // Add in the digit we just interpreted
     if (apdigit.isSingleWord())
-      apdigit.VAL = digit;
+      apdigit.U.VAL = digit;
     else
-      apdigit.pVal[0] = digit;
+      apdigit.U.pVal[0] = digit;
     *this += apdigit;
   }
   // If its negative, put it in two's complement form