path: root/src/jit/bitsetasshortlong.h

// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.

// A set of integers in the range [0..N], for some N defined by the "Env" (via "BitSetTraits").
//
// Represented as a pointer-sized item.  If N bits can fit in this item, the representation is "direct"; otherwise,
// the item is a pointer to an array of K size_t's, where K is the number of size_t's necessary to hold N bits.

#ifndef bitSetAsShortLong_DEFINED
#define bitSetAsShortLong_DEFINED 1

#include "bitset.h"
#include "compilerbitsettraits.h"

typedef size_t* BitSetShortLongRep;

template <typename Env, typename BitSetTraits>
class BitSetOps</*BitSetType*/ BitSetShortLongRep,
                /*Brand*/ BSShortLong,
                /*Env*/ Env,
                /*BitSetTraits*/ BitSetTraits>
{
public:
    typedef BitSetShortLongRep Rep;

private:
    static const unsigned BitsInSizeT = sizeof(size_t) * BitSetSupport::BitsInByte;

    inline static bool IsShort(Env env)
    {
        return BitSetTraits::GetArrSize(env, sizeof(size_t)) <= 1;
    }

    // The operations on the "long" (pointer-to-array-of-size_t) versions of the representation.
    static void AssignLong(Env env, BitSetShortLongRep& lhs, BitSetShortLongRep rhs);
    static BitSetShortLongRep MakeSingletonLong(Env env, unsigned bitNum);
    static BitSetShortLongRep MakeCopyLong(Env env, BitSetShortLongRep bs);
    static bool IsEmptyLong(Env env, BitSetShortLongRep bs);
    static unsigned CountLong(Env env, BitSetShortLongRep bs);
    static bool IsEmptyUnionLong(Env env, BitSetShortLongRep bs1, BitSetShortLongRep bs2);
    static void UnionDLong(Env env, BitSetShortLongRep& bs1, BitSetShortLongRep bs2);
    static void DiffDLong(Env env, BitSetShortLongRep& bs1, BitSetShortLongRep bs2);
    static void AddElemDLong(Env env, BitSetShortLongRep& bs, unsigned i);
    static bool TryAddElemDLong(Env env, BitSetShortLongRep& bs, unsigned i);
    static void RemoveElemDLong(Env env, BitSetShortLongRep& bs, unsigned i);
    static void ClearDLong(Env env, BitSetShortLongRep& bs);
    static BitSetShortLongRep MakeUninitArrayBits(Env env);
    static BitSetShortLongRep MakeEmptyArrayBits(Env env);
    static BitSetShortLongRep MakeFullArrayBits(Env env);
    static bool IsMemberLong(Env env, BitSetShortLongRep bs, unsigned i);
    static bool EqualLong(Env env, BitSetShortLongRep bs1, BitSetShortLongRep bs2);
    static bool IsSubsetLong(Env env, BitSetShortLongRep bs1, BitSetShortLongRep bs2);
    static bool IsEmptyIntersectionLong(Env env, BitSetShortLongRep bs1, BitSetShortLongRep bs2);
    static void IntersectionDLong(Env env, BitSetShortLongRep& bs1, BitSetShortLongRep bs2);
    static void DataFlowDLong(Env                      env,
                              BitSetShortLongRep&      out,
                              const BitSetShortLongRep gen,
                              const BitSetShortLongRep in);
    static void LivenessDLong(Env                      env,
                              BitSetShortLongRep&      in,
                              const BitSetShortLongRep def,
                              const BitSetShortLongRep use,
                              const BitSetShortLongRep out);
#ifdef DEBUG
    static const char* ToStringLong(Env env, BitSetShortLongRep bs);
#endif

public:
    inline static BitSetShortLongRep UninitVal()
    {
        return nullptr;
    }

    static bool MayBeUninit(BitSetShortLongRep bs)
    {
        return bs == UninitVal();
    }

    static void Assign(Env env, BitSetShortLongRep& lhs, BitSetShortLongRep rhs)
    {
        // We can't assert that rhs != UninitVal in the Short case, because in that
        // case it's a legal value.
        if (IsShort(env))
        {
            // Both are short.
            lhs = rhs;
        }
        else if (lhs == UninitVal())
        {
            assert(rhs != UninitVal());
            lhs = MakeCopy(env, rhs);
        }
        else
        {
            AssignLong(env, lhs, rhs);
        }
    }

    static void AssignAllowUninitRhs(Env env, BitSetShortLongRep& lhs, BitSetShortLongRep rhs)
    {
        if (IsShort(env))
        {
            // Both are short.
            lhs = rhs;
        }
        else if (rhs == UninitVal())
        {
            lhs = rhs;
        }
        else if (lhs == UninitVal())
        {
            lhs = MakeCopy(env, rhs);
        }
        else
        {
            AssignLong(env, lhs, rhs);
        }
    }

    static void AssignNoCopy(Env env, BitSetShortLongRep& lhs, BitSetShortLongRep rhs)
    {
        lhs = rhs;
    }

    static void ClearD(Env env, BitSetShortLongRep& bs)
    {
        if (IsShort(env))
        {
            bs = (BitSetShortLongRep) nullptr;
        }
        else
        {
            assert(bs != UninitVal());
            ClearDLong(env, bs);
        }
    }

    static BitSetShortLongRep MakeSingleton(Env env, unsigned bitNum)
    {
        assert(bitNum < BitSetTraits::GetSize(env));
        if (IsShort(env))
        {
            return BitSetShortLongRep(((size_t)1) << bitNum);
        }
        else
        {
            return MakeSingletonLong(env, bitNum);
        }
    }

    static BitSetShortLongRep MakeCopy(Env env, BitSetShortLongRep bs)
    {
        if (IsShort(env))
        {
            return bs;
        }
        else
        {
            return MakeCopyLong(env, bs);
        }
    }

    static bool IsEmpty(Env env, BitSetShortLongRep bs)
    {
        if (IsShort(env))
        {
            return bs == nullptr;
        }
        else
        {
            assert(bs != UninitVal());
            return IsEmptyLong(env, bs);
        }
    }

    static unsigned Count(Env env, BitSetShortLongRep bs)
    {
        if (IsShort(env))
        {
            return BitSetSupport::CountBitsInIntegral(size_t(bs));
        }
        else
        {
            assert(bs != UninitVal());
            return CountLong(env, bs);
        }
    }

    static bool IsEmptyUnion(Env env, BitSetShortLongRep bs1, BitSetShortLongRep bs2)
    {
        if (IsShort(env))
        {
            return (((size_t)bs1) | ((size_t)bs2)) == 0;
        }
        else
        {
            return IsEmptyUnionLong(env, bs1, bs2);
        }
    }

    static void UnionD(Env env, BitSetShortLongRep& bs1, BitSetShortLongRep bs2)
    {
        if (IsShort(env))
        {
            bs1 = (BitSetShortLongRep)(((size_t)bs1) | ((size_t)bs2));
        }
        else
        {
            UnionDLong(env, bs1, bs2);
        }
    }
    static BitSetShortLongRep Union(Env env, BitSetShortLongRep bs1, BitSetShortLongRep bs2)
    {
        BitSetShortLongRep res = MakeCopy(env, bs1);
        UnionD(env, res, bs2);
        return res;
    }

    static void DiffD(Env env, BitSetShortLongRep& bs1, BitSetShortLongRep bs2)
    {
        if (IsShort(env))
        {
            bs1 = (BitSetShortLongRep)(((size_t)bs1) & (~(size_t)bs2));
        }
        else
        {
            DiffDLong(env, bs1, bs2);
        }
    }
    static BitSetShortLongRep Diff(Env env, BitSetShortLongRep bs1, BitSetShortLongRep bs2)
    {
        BitSetShortLongRep res = MakeCopy(env, bs1);
        DiffD(env, res, bs2);
        return res;
    }

    static void RemoveElemD(Env env, BitSetShortLongRep& bs, unsigned i)
    {
        assert(i < BitSetTraits::GetSize(env));
        if (IsShort(env))
        {
            size_t mask = ((size_t)1) << i;
            mask        = ~mask;
            bs          = (BitSetShortLongRep)(((size_t)bs) & mask);
        }
        else
        {
            assert(bs != UninitVal());
            RemoveElemDLong(env, bs, i);
        }
    }
    static BitSetShortLongRep RemoveElem(Env env, BitSetShortLongRep bs, unsigned i)
    {
        BitSetShortLongRep res = MakeCopy(env, bs);
        RemoveElemD(env, res, i);
        return res;
    }

    static void AddElemD(Env env, BitSetShortLongRep& bs, unsigned i)
    {
        assert(i < BitSetTraits::GetSize(env));
        if (IsShort(env))
        {
            size_t mask = ((size_t)1) << i;
            bs          = (BitSetShortLongRep)(((size_t)bs) | mask);
        }
        else
        {
            AddElemDLong(env, bs, i);
        }
    }
    static BitSetShortLongRep AddElem(Env env, BitSetShortLongRep bs, unsigned i)
    {
        BitSetShortLongRep res = MakeCopy(env, bs);
        AddElemD(env, res, i);
        return res;
    }

    static bool TryAddElemD(Env env, BitSetShortLongRep& bs, unsigned i)
    {
        assert(i < BitSetTraits::GetSize(env));
        if (IsShort(env))
        {
            size_t mask  = ((size_t)1) << i;
            size_t bits  = (size_t)bs;
            bool   added = (bits & mask) == 0;
            bs           = (BitSetShortLongRep)(bits | mask);
            return added;
        }
        else
        {
            return TryAddElemDLong(env, bs, i);
        }
    }

    static bool IsMember(Env env, const BitSetShortLongRep bs, unsigned i)
    {
        assert(i < BitSetTraits::GetSize(env));
        if (IsShort(env))
        {
            size_t mask = ((size_t)1) << i;
            return (((size_t)bs) & mask) != 0;
        }
        else
        {
            assert(bs != UninitVal());
            return IsMemberLong(env, bs, i);
        }
    }

    static void IntersectionD(Env env, BitSetShortLongRep& bs1, BitSetShortLongRep bs2)
    {
        if (IsShort(env))
        {
            size_t val = (size_t)bs1;

            val &= (size_t)bs2;
            bs1 = (BitSetShortLongRep)val;
        }
        else
        {
            IntersectionDLong(env, bs1, bs2);
        }
    }

    static BitSetShortLongRep Intersection(Env env, BitSetShortLongRep bs1, BitSetShortLongRep bs2)
    {
        BitSetShortLongRep res = MakeCopy(env, bs1);
        IntersectionD(env, res, bs2);
        return res;
    }
    static bool IsEmptyIntersection(Env env, BitSetShortLongRep bs1, BitSetShortLongRep bs2)
    {
        if (IsShort(env))
        {
            return (((size_t)bs1) & ((size_t)bs2)) == 0;
        }
        else
        {
            return IsEmptyIntersectionLong(env, bs1, bs2);
        }
    }

    static void DataFlowD(Env env, BitSetShortLongRep& out, const BitSetShortLongRep gen, const BitSetShortLongRep in)
    {
        if (IsShort(env))
        {
            (size_t&)out = (size_t)out & ((size_t)gen | (size_t)in);
        }
        else
        {
            DataFlowDLong(env, out, gen, in);
        }
    }

    static void LivenessD(Env                      env,
                          BitSetShortLongRep&      in,
                          const BitSetShortLongRep def,
                          const BitSetShortLongRep use,
                          const BitSetShortLongRep out)
    {
        if (IsShort(env))
        {
            (size_t&)in = (size_t)use | ((size_t)out & ~(size_t)def);
        }
        else
        {
            LivenessDLong(env, in, def, use, out);
        }
    }

    static bool IsSubset(Env env, BitSetShortLongRep bs1, BitSetShortLongRep bs2)
    {
        if (IsShort(env))
        {
            size_t u1 = (size_t)bs1;
            size_t u2 = (size_t)bs2;
            return (u1 & u2) == u1;
        }
        else
        {
            return IsSubsetLong(env, bs1, bs2);
        }
    }

    static bool Equal(Env env, BitSetShortLongRep bs1, BitSetShortLongRep bs2)
    {
        if (IsShort(env))
        {
            return (size_t)bs1 == (size_t)bs2;
        }
        else
        {
            return EqualLong(env, bs1, bs2);
        }
    }

#ifdef DEBUG
    // Returns a string valid until the allocator releases the memory.
    static const char* ToString(Env env, BitSetShortLongRep bs)
    {
        if (IsShort(env))
        {
            assert(sizeof(BitSetShortLongRep) == sizeof(size_t));
            const int CharsForSizeT  = sizeof(size_t) * 2;
            char*     res            = nullptr;
            const int ShortAllocSize = CharsForSizeT + 4;
            res                      = (char*)BitSetTraits::DebugAlloc(env, ShortAllocSize);
            size_t   bits            = (size_t)bs;
            unsigned remaining       = ShortAllocSize;
            char*    ptr             = res;
            if (sizeof(size_t) == sizeof(int64_t))
            {
                sprintf_s(ptr, remaining, "%016zX", bits);
            }
            else
            {
                assert(sizeof(size_t) == sizeof(int));
                sprintf_s(ptr, remaining, "%08zX", bits);
            }
            return res;
        }
        else
        {
            return ToStringLong(env, bs);
        }
    }
#endif

    static BitSetShortLongRep MakeEmpty(Env env)
    {
        if (IsShort(env))
        {
            return nullptr;
        }
        else
        {
            return MakeEmptyArrayBits(env);
        }
    }

    static BitSetShortLongRep MakeFull(Env env)
    {
        if (IsShort(env))
        {
            // Can't just shift by numBits+1, since that might be 32 (and (1 << 32( == 1, for an unsigned).
            unsigned numBits = BitSetTraits::GetSize(env);
            if (numBits == BitsInSizeT)
            {
                // Can't use the implementation below to get all 1's...
                return BitSetShortLongRep(size_t(-1));
            }
            else
            {
                return BitSetShortLongRep((size_t(1) << numBits) - 1);
            }
        }
        else
        {
            return MakeFullArrayBits(env);
        }
    }

    class Iter
    {
        // The BitSet that we're iterating over. This is updated to point at the current
        // size_t set of bits.
        BitSetShortLongRep m_bs;

        // The end of the iteration.
        BitSetShortLongRep m_bsEnd;

        // The remaining bits to be iterated over in the current size_t set of bits.
        // In the "short" case, these are all the remaining bits.
        // In the "long" case, these are remaining bits in the current element;
        // these and the bits in the remaining elements comprise the remaining bits.
        size_t m_bits;

        // The number of bits that have already been iterated over (set or clear). If you
        // add this to the bit number of the next bit in "m_bits", you get the proper bit number of that
        // bit in "m_bs". This is only updated when we increment m_bs.
        unsigned m_bitNum;

    public:
        Iter(Env env, const BitSetShortLongRep& bs) : m_bs(bs), m_bitNum(0)
        {
            if (BitSetOps::IsShort(env))
            {
                m_bits = (size_t)bs;

                // Set the iteration end condition, valid even though this is not a pointer in the short case.
                m_bsEnd = bs + 1;
            }
            else
            {
                assert(bs != BitSetOps::UninitVal());
                m_bits = bs[0];

                unsigned len = BitSetTraits::GetArrSize(env, sizeof(size_t));
                m_bsEnd      = bs + len;
            }
        }

        bool NextElem(unsigned* pElem)
        {
#if BITSET_TRACK_OPCOUNTS
            BitSetStaticsImpl::RecordOp(BitSetStaticsImpl::BSOP_NextBit);
#endif
            for (;;)
            {
                DWORD nextBit;
                BOOL  hasBit;
#ifdef _HOST_64BIT_
                static_assert_no_msg(sizeof(size_t) == 8);
                hasBit = BitScanForward64(&nextBit, m_bits);
#else
                static_assert_no_msg(sizeof(size_t) == 4);
                hasBit = BitScanForward(&nextBit, m_bits);
#endif

                // If there's a bit, doesn't matter if we're short or long.
                if (hasBit)
                {
                    *pElem = m_bitNum + nextBit;
                    m_bits &= ~(((size_t)1) << nextBit); // clear bit we just found so we don't find it again
                    return true;
                }
                else
                {
                    // Go to the next size_t bit element. For short bitsets, this will hit the end condition
                    // and exit.
                    ++m_bs;
                    if (m_bs == m_bsEnd)
                    {
                        return false;
                    }

                    // If we get here, it's not a short type, so get the next size_t element.
                    m_bitNum += sizeof(size_t) * BitSetSupport::BitsInByte;
                    m_bits = *m_bs;
                }
            }
        }
    };

    typedef const BitSetShortLongRep& ValArgType;
    typedef BitSetShortLongRep        RetValType;
};

template <typename Env, typename BitSetTraits>
void BitSetOps</*BitSetType*/ BitSetShortLongRep,
               /*Brand*/ BSShortLong,
               /*Env*/ Env,
               /*BitSetTraits*/ BitSetTraits>::AssignLong(Env env, BitSetShortLongRep& lhs, BitSetShortLongRep rhs)
{
    assert(!IsShort(env));
    unsigned len = BitSetTraits::GetArrSize(env, sizeof(size_t));
    for (unsigned i = 0; i < len; i++)
    {
        lhs[i] = rhs[i];
    }
}

template <typename Env, typename BitSetTraits>
BitSetShortLongRep BitSetOps</*BitSetType*/ BitSetShortLongRep,
                             /*Brand*/ BSShortLong,
                             /*Env*/ Env,
                             /*BitSetTraits*/ BitSetTraits>::MakeSingletonLong(Env env, unsigned bitNum)
{
    assert(!IsShort(env));
    BitSetShortLongRep res   = MakeEmptyArrayBits(env);
    unsigned           index = bitNum / BitsInSizeT;
    res[index]               = ((size_t)1) << (bitNum % BitsInSizeT);
    return res;
}

template <typename Env, typename BitSetTraits>
BitSetShortLongRep BitSetOps</*BitSetType*/ BitSetShortLongRep,
                             /*Brand*/ BSShortLong,
                             /*Env*/ Env,
                             /*BitSetTraits*/ BitSetTraits>::MakeCopyLong(Env env, BitSetShortLongRep bs)
{
    assert(!IsShort(env));
    BitSetShortLongRep res = MakeUninitArrayBits(env);
    unsigned           len = BitSetTraits::GetArrSize(env, sizeof(size_t));
    for (unsigned i = 0; i < len; i++)
    {
        res[i] = bs[i];
    }
    return res;
}

template <typename Env, typename BitSetTraits>
bool BitSetOps</*BitSetType*/ BitSetShortLongRep,
               /*Brand*/ BSShortLong,
               /*Env*/ Env,
               /*BitSetTraits*/ BitSetTraits>::IsEmptyLong(Env env, BitSetShortLongRep bs)
{
    assert(!IsShort(env));
    unsigned len = BitSetTraits::GetArrSize(env, sizeof(size_t));
    for (unsigned i = 0; i < len; i++)
    {
        if (bs[i] != 0)
        {
            return false;
        }
    }
    return true;
}

template <typename Env, typename BitSetTraits>
unsigned BitSetOps</*BitSetType*/ BitSetShortLongRep,
                   /*Brand*/ BSShortLong,
                   /*Env*/ Env,
                   /*BitSetTraits*/ BitSetTraits>::CountLong(Env env, BitSetShortLongRep bs)
{
    assert(!IsShort(env));
    unsigned len = BitSetTraits::GetArrSize(env, sizeof(size_t));
    unsigned res = 0;
    for (unsigned i = 0; i < len; i++)
    {
        res += BitSetSupport::CountBitsInIntegral(bs[i]);
    }
    return res;
}

template <typename Env, typename BitSetTraits>
void BitSetOps</*BitSetType*/ BitSetShortLongRep,
               /*Brand*/ BSShortLong,
               /*Env*/ Env,
               /*BitSetTraits*/ BitSetTraits>::UnionDLong(Env env, BitSetShortLongRep& bs1, BitSetShortLongRep bs2)
{
    assert(!IsShort(env));
    unsigned len = BitSetTraits::GetArrSize(env, sizeof(size_t));
    for (unsigned i = 0; i < len; i++)
    {
        bs1[i] |= bs2[i];
    }
}

template <typename Env, typename BitSetTraits>
void BitSetOps</*BitSetType*/ BitSetShortLongRep,
               /*Brand*/ BSShortLong,
               /*Env*/ Env,
               /*BitSetTraits*/ BitSetTraits>::DiffDLong(Env env, BitSetShortLongRep& bs1, BitSetShortLongRep bs2)
{
    assert(!IsShort(env));
    unsigned len = BitSetTraits::GetArrSize(env, sizeof(size_t));
    for (unsigned i = 0; i < len; i++)
    {
        bs1[i] &= ~bs2[i];
    }
}

template <typename Env, typename BitSetTraits>
void BitSetOps</*BitSetType*/ BitSetShortLongRep,
               /*Brand*/ BSShortLong,
               /*Env*/ Env,
               /*BitSetTraits*/ BitSetTraits>::AddElemDLong(Env env, BitSetShortLongRep& bs, unsigned i)
{
    assert(!IsShort(env));
    unsigned index = i / BitsInSizeT;
    size_t   mask  = ((size_t)1) << (i % BitsInSizeT);
    bs[index] |= mask;
}

template <typename Env, typename BitSetTraits>
bool BitSetOps</*BitSetType*/ BitSetShortLongRep,
               /*Brand*/ BSShortLong,
               /*Env*/ Env,
               /*BitSetTraits*/ BitSetTraits>::TryAddElemDLong(Env env, BitSetShortLongRep& bs, unsigned i)
{
    assert(!IsShort(env));
    unsigned index = i / BitsInSizeT;
    size_t   mask  = ((size_t)1) << (i % BitsInSizeT);
    size_t   bits  = bs[index];
    bool     added = (bits & mask) == 0;
    bs[index]      = bits | mask;
    return added;
}

template <typename Env, typename BitSetTraits>
void BitSetOps</*BitSetType*/ BitSetShortLongRep,
               /*Brand*/ BSShortLong,
               /*Env*/ Env,
               /*BitSetTraits*/ BitSetTraits>::RemoveElemDLong(Env env, BitSetShortLongRep& bs, unsigned i)
{
    assert(!IsShort(env));
    unsigned index = i / BitsInSizeT;
    size_t   mask  = ((size_t)1) << (i % BitsInSizeT);
    mask           = ~mask;
    bs[index] &= mask;
}

template <typename Env, typename BitSetTraits>
void BitSetOps</*BitSetType*/ BitSetShortLongRep,
               /*Brand*/ BSShortLong,
               /*Env*/ Env,
               /*BitSetTraits*/ BitSetTraits>::ClearDLong(Env env, BitSetShortLongRep& bs)
{
    assert(!IsShort(env));
    unsigned len = BitSetTraits::GetArrSize(env, sizeof(size_t));
    for (unsigned i = 0; i < len; i++)
    {
        bs[i] = 0;
    }
}

template <typename Env, typename BitSetTraits>
BitSetShortLongRep BitSetOps</*BitSetType*/ BitSetShortLongRep,
                             /*Brand*/ BSShortLong,
                             /*Env*/ Env,
                             /*BitSetTraits*/ BitSetTraits>::MakeUninitArrayBits(Env env)
{
    assert(!IsShort(env));
    unsigned len = BitSetTraits::GetArrSize(env, sizeof(size_t));
    assert(len > 1); // Or else would not require an array.
    return (BitSetShortLongRep)(BitSetTraits::Alloc(env, len * sizeof(size_t)));
}

template <typename Env, typename BitSetTraits>
BitSetShortLongRep BitSetOps</*BitSetType*/ BitSetShortLongRep,
                             /*Brand*/ BSShortLong,
                             /*Env*/ Env,
                             /*BitSetTraits*/ BitSetTraits>::MakeEmptyArrayBits(Env env)
{
    assert(!IsShort(env));
    unsigned len = BitSetTraits::GetArrSize(env, sizeof(size_t));
    assert(len > 1); // Or else would not require an array.
    BitSetShortLongRep res = (BitSetShortLongRep)(BitSetTraits::Alloc(env, len * sizeof(size_t)));
    for (unsigned i = 0; i < len; i++)
    {
        res[i] = 0;
    }
    return res;
}

template <typename Env, typename BitSetTraits>
BitSetShortLongRep BitSetOps</*BitSetType*/ BitSetShortLongRep,
                             /*Brand*/ BSShortLong,
                             /*Env*/ Env,
                             /*BitSetTraits*/ BitSetTraits>::MakeFullArrayBits(Env env)
{
    assert(!IsShort(env));
    unsigned len = BitSetTraits::GetArrSize(env, sizeof(size_t));
    assert(len > 1); // Or else would not require an array.
    BitSetShortLongRep res = (BitSetShortLongRep)(BitSetTraits::Alloc(env, len * sizeof(size_t)));
    for (unsigned i = 0; i < len - 1; i++)
    {
        res[i] = size_t(-1);
    }
    // Start with all ones, shift in zeros in the last elem.
    unsigned lastElemBits = (BitSetTraits::GetSize(env) - 1) % BitsInSizeT + 1;
    res[len - 1]          = (size_t(-1) >> (BitsInSizeT - lastElemBits));
    return res;
}

template <typename Env, typename BitSetTraits>
bool BitSetOps</*BitSetType*/ BitSetShortLongRep,
               /*Brand*/ BSShortLong,
               /*Env*/ Env,
               /*BitSetTraits*/ BitSetTraits>::IsMemberLong(Env env, BitSetShortLongRep bs, unsigned i)
{
    assert(!IsShort(env));
    unsigned index     = i / BitsInSizeT;
    unsigned bitInElem = (i % BitsInSizeT);
    size_t   mask      = ((size_t)1) << bitInElem;
    return (bs[index] & mask) != 0;
}

template <typename Env, typename BitSetTraits>
void BitSetOps</*BitSetType*/ BitSetShortLongRep,
               /*Brand*/ BSShortLong,
               /*Env*/ Env,
               /*BitSetTraits*/ BitSetTraits>::IntersectionDLong(Env                 env,
                                                                 BitSetShortLongRep& bs1,
                                                                 BitSetShortLongRep  bs2)
{
    assert(!IsShort(env));
    unsigned len = BitSetTraits::GetArrSize(env, sizeof(size_t));
    for (unsigned i = 0; i < len; i++)
    {
        bs1[i] &= bs2[i];
    }
}

template <typename Env, typename BitSetTraits>
bool BitSetOps</*BitSetType*/ BitSetShortLongRep,
               /*Brand*/ BSShortLong,
               /*Env*/ Env,
               /*BitSetTraits*/ BitSetTraits>::IsEmptyIntersectionLong(Env                env,
                                                                       BitSetShortLongRep bs1,
                                                                       BitSetShortLongRep bs2)
{
    assert(!IsShort(env));
    unsigned len = BitSetTraits::GetArrSize(env, sizeof(size_t));
    for (unsigned i = 0; i < len; i++)
    {
        if ((bs1[i] & bs2[i]) != 0)
        {
            return false;
        }
    }
    return true;
}

template <typename Env, typename BitSetTraits>
bool BitSetOps</*BitSetType*/ BitSetShortLongRep,
               /*Brand*/ BSShortLong,
               /*Env*/ Env,
               /*BitSetTraits*/ BitSetTraits>::IsEmptyUnionLong(Env env, BitSetShortLongRep bs1, BitSetShortLongRep bs2)
{
    assert(!IsShort(env));
    unsigned len = BitSetTraits::GetArrSize(env, sizeof(size_t));
    for (unsigned i = 0; i < len; i++)
    {
        if ((bs1[i] | bs2[i]) != 0)
        {
            return false;
        }
    }
    return true;
}

template <typename Env, typename BitSetTraits>
void BitSetOps</*BitSetType*/ BitSetShortLongRep,
               /*Brand*/ BSShortLong,
               /*Env*/ Env,
               /*BitSetTraits*/ BitSetTraits>::DataFlowDLong(Env                      env,
                                                             BitSetShortLongRep&      out,
                                                             const BitSetShortLongRep gen,
                                                             const BitSetShortLongRep in)
{
    assert(!IsShort(env));
    unsigned len = BitSetTraits::GetArrSize(env, sizeof(size_t));
    for (unsigned i = 0; i < len; i++)
    {
        out[i] = out[i] & (gen[i] | in[i]);
    }
}

template <typename Env, typename BitSetTraits>
void BitSetOps</*BitSetType*/ BitSetShortLongRep,
               /*Brand*/ BSShortLong,
               /*Env*/ Env,
               /*BitSetTraits*/ BitSetTraits>::LivenessDLong(Env                      env,
                                                             BitSetShortLongRep&      in,
                                                             const BitSetShortLongRep def,
                                                             const BitSetShortLongRep use,
                                                             const BitSetShortLongRep out)
{
    assert(!IsShort(env));
    unsigned len = BitSetTraits::GetArrSize(env, sizeof(size_t));
    for (unsigned i = 0; i < len; i++)
    {
        in[i] = use[i] | (out[i] & ~def[i]);
    }
}

template <typename Env, typename BitSetTraits>
bool BitSetOps</*BitSetType*/ BitSetShortLongRep,
               /*Brand*/ BSShortLong,
               /*Env*/ Env,
               /*BitSetTraits*/ BitSetTraits>::EqualLong(Env env, BitSetShortLongRep bs1, BitSetShortLongRep bs2)
{
    assert(!IsShort(env));
    unsigned len = BitSetTraits::GetArrSize(env, sizeof(size_t));
    for (unsigned i = 0; i < len; i++)
    {
        if (bs1[i] != bs2[i])
        {
            return false;
        }
    }
    return true;
}

template <typename Env, typename BitSetTraits>
bool BitSetOps</*BitSetType*/ BitSetShortLongRep,
               /*Brand*/ BSShortLong,
               /*Env*/ Env,
               /*BitSetTraits*/ BitSetTraits>::IsSubsetLong(Env env, BitSetShortLongRep bs1, BitSetShortLongRep bs2)
{
    assert(!IsShort(env));
    unsigned len = BitSetTraits::GetArrSize(env, sizeof(size_t));
    for (unsigned i = 0; i < len; i++)
    {
        if ((bs1[i] & bs2[i]) != bs1[i])
        {
            return false;
        }
    }
    return true;
}

#ifdef DEBUG
template <typename Env, typename BitSetTraits>
const char* BitSetOps</*BitSetType*/ BitSetShortLongRep,
                      /*Brand*/ BSShortLong,
                      /*Env*/ Env,
                      /*BitSetTraits*/ BitSetTraits>::ToStringLong(Env env, BitSetShortLongRep bs)
{
    assert(!IsShort(env));
    unsigned  len           = BitSetTraits::GetArrSize(env, sizeof(size_t));
    const int CharsForSizeT = sizeof(size_t) * 2;
    unsigned  allocSz       = len * CharsForSizeT + 4;
    unsigned  remaining     = allocSz;
    char*     res           = (char*)BitSetTraits::DebugAlloc(env, allocSz);
    char*     temp          = res;
    for (unsigned i = len; 0 < i; i--)
    {
        size_t bits = bs[i - 1];
        for (unsigned bytesDone = 0; bytesDone < sizeof(size_t); bytesDone += sizeof(unsigned))
        {
            unsigned bits0 = (unsigned)bits;
            sprintf_s(temp, remaining, "%08X", bits0);
            temp += 8;
            remaining -= 8;
            bytesDone += 4;
            assert(sizeof(unsigned) == 4);
            // Doing this twice by 16, rather than once by 32, avoids warnings when size_t == unsigned.
            bits = bits >> 16;
            bits = bits >> 16;
        }
    }
    return res;
}
#endif

#endif // bitSetAsShortLong_DEFINED