+ // Use ^ instead of - because both gcc and llvm can remove the associated ^
+ // in the __builtin_clz intrinsic on x86.
+ return countLeadingZeros(Val, ZB_Undefined) ^
+ (std::numeric_limits<T>::digits - 1);
+}
+
+// Disable signed.
+template <typename T>
+typename std::enable_if<std::numeric_limits<T>::is_integer &&
+ std::numeric_limits<T>::is_signed, T>::type
+findLastSet(T Val, ZeroBehavior ZB = ZB_Max) LLVM_DELETED_FUNCTION;
+
+/// \brief Macro compressed bit reversal table for 256 bits.
+///
+/// http://graphics.stanford.edu/~seander/bithacks.html#BitReverseTable
+static const unsigned char BitReverseTable256[256] = {
+#define R2(n) n, n + 2 * 64, n + 1 * 64, n + 3 * 64
+#define R4(n) R2(n), R2(n + 2 * 16), R2(n + 1 * 16), R2(n + 3 * 16)
+#define R6(n) R4(n), R4(n + 2 * 4), R4(n + 1 * 4), R4(n + 3 * 4)
+ R6(0), R6(2), R6(1), R6(3)
+#undef R2
+#undef R4
+#undef R6
+};
+
+/// \brief Reverse the bits in \p Val.
+template <typename T>
+T reverseBits(T Val) {
+ unsigned char in[sizeof(Val)];
+ unsigned char out[sizeof(Val)];
+ std::memcpy(in, &Val, sizeof(Val));
+ for (unsigned i = 0; i < sizeof(Val); ++i)
+ out[(sizeof(Val) - i) - 1] = BitReverseTable256[in[i]];
+ std::memcpy(&Val, out, sizeof(Val));
+ return Val;
+}
+
+// NOTE: The following support functions use the _32/_64 extensions instead of
+// type overloading so that signed and unsigned integers can be used without
+// ambiguity.
+
+/// Hi_32 - This function returns the high 32 bits of a 64 bit value.
+inline uint32_t Hi_32(uint64_t Value) {
+ return static_cast<uint32_t>(Value >> 32);
+}
+
+/// Lo_32 - This function returns the low 32 bits of a 64 bit value.
+inline uint32_t Lo_32(uint64_t Value) {
+ return static_cast<uint32_t>(Value);
+}
+
+/// Make_64 - This functions makes a 64-bit integer from a high / low pair of
+/// 32-bit integers.
+inline uint64_t Make_64(uint32_t High, uint32_t Low) {
+ return ((uint64_t)High << 32) | (uint64_t)Low;
+}
+
+/// isInt - Checks if an integer fits into the given bit width.
+template<unsigned N>
+inline bool isInt(int64_t x) {
+ return N >= 64 || (-(INT64_C(1)<<(N-1)) <= x && x < (INT64_C(1)<<(N-1)));
+}
+// Template specializations to get better code for common cases.
+template<>
+inline bool isInt<8>(int64_t x) {
+ return static_cast<int8_t>(x) == x;
+}
+template<>
+inline bool isInt<16>(int64_t x) {
+ return static_cast<int16_t>(x) == x;
+}
+template<>
+inline bool isInt<32>(int64_t x) {
+ return static_cast<int32_t>(x) == x;
+}
+
+/// isShiftedInt<N,S> - Checks if a signed integer is an N bit number shifted
+/// left by S.
+template<unsigned N, unsigned S>
+inline bool isShiftedInt(int64_t x) {
+ return isInt<N+S>(x) && (x % (1<<S) == 0);
+}
+
+/// isUInt - Checks if an unsigned integer fits into the given bit width.
+template<unsigned N>
+inline bool isUInt(uint64_t x) {
+ return N >= 64 || x < (UINT64_C(1)<<(N));
+}
+// Template specializations to get better code for common cases.
+template<>
+inline bool isUInt<8>(uint64_t x) {
+ return static_cast<uint8_t>(x) == x;
+}
+template<>
+inline bool isUInt<16>(uint64_t x) {
+ return static_cast<uint16_t>(x) == x;
+}
+template<>
+inline bool isUInt<32>(uint64_t x) {
+ return static_cast<uint32_t>(x) == x;
+}
+
+/// isShiftedUInt<N,S> - Checks if a unsigned integer is an N bit number shifted
+/// left by S.
+template<unsigned N, unsigned S>
+inline bool isShiftedUInt(uint64_t x) {
+ return isUInt<N+S>(x) && (x % (1<<S) == 0);
+}
+
+/// isUIntN - Checks if an unsigned integer fits into the given (dynamic)
+/// bit width.
+inline bool isUIntN(unsigned N, uint64_t x) {
+ return x == (x & (~0ULL >> (64 - N)));
+}
+
+/// isIntN - Checks if an signed integer fits into the given (dynamic)
+/// bit width.
+inline bool isIntN(unsigned N, int64_t x) {
+ return N >= 64 || (-(INT64_C(1)<<(N-1)) <= x && x < (INT64_C(1)<<(N-1)));
+}
+
+/// isMask_32 - This function returns true if the argument is a sequence of ones
+/// starting at the least significant bit with the remainder zero (32 bit
+/// version). Ex. isMask_32(0x0000FFFFU) == true.
+inline bool isMask_32(uint32_t Value) {