vec_pred_reg.hh

Go to the documentation of this file.

// Copyright (c) 2017 ARM Limited
// All rights reserved
//
// The license below extends only to copyright in the software and shall
// not be construed as granting a license to any other intellectual
// property including but not limited to intellectual property relating
// to a hardware implementation of the functionality of the software
// licensed hereunder.  You may use the software subject to the license
// terms below provided that you ensure that this notice is replicated
// unmodified and in its entirety in all distributions of the software,
// modified or unmodified, in source code or in binary form.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met: redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer;
// redistributions in binary form must reproduce the above copyright
// notice, this list of conditions and the following disclaimer in the
// documentation and/or other materials provided with the distribution;
// neither the name of the copyright holders nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
#ifndef __ARCH_GENERIC_VEC_PRED_REG_HH__
#define __ARCH_GENERIC_VEC_PRED_REG_HH__
 
#include <array>
#include <cassert>
#include <cstdint>
#include <string>
#include <type_traits>
#include <vector>
 
#include "base/cprintf.hh"
#include "sim/serialize_handlers.hh"
 
namespace gem5
{
 
template <size_t NumBits, bool Packed>
class VecPredRegContainer;
 
template <typename VecElem, size_t NumElems, bool Packed, bool Const>
class VecPredRegT
{
  protected:
    static constexpr size_t NUM_BITS = Packed ? NumElems :
                                                sizeof(VecElem) * NumElems;
 
  public:
    using Container = typename std::conditional_t<
        Const,
        const VecPredRegContainer<NUM_BITS, Packed>,
        VecPredRegContainer<NUM_BITS, Packed>>;
 
  protected:
    // Alias for this type
    using MyClass = VecPredRegT<VecElem, NumElems, Packed, Const>;
    Container& container;
 
  public:
    VecPredRegT(Container& c) : container(c) {}
 
    template<bool Condition = !Const>
    std::enable_if_t<Condition> reset() { container.reset(); }
 
    template<bool Condition = !Const>
    std::enable_if_t<Condition> set() { container.set(); }
 
    template<bool Condition = !Const>
    std::enable_if_t<Condition, MyClass&>
    operator=(const MyClass& that)
    {
        container = that.container;
        return *this;
    }
 
    const bool&
    operator[](size_t idx) const
    {
        return container[idx * (Packed ? 1 : sizeof(VecElem))];
    }
 
    template<bool Condition = !Const>
    std::enable_if_t<Condition, bool&>
    operator[](size_t idx)
    {
        return container[idx * (Packed ? 1 : sizeof(VecElem))];
    }
 
    uint8_t
    getRaw(size_t idx) const
    {
        return container.getBits(idx * (Packed ? 1 : sizeof(VecElem)),
                (Packed ? 1 : sizeof(VecElem)));
    }
 
    template<bool Condition = !Const>
    std::enable_if_t<Condition>
    setRaw(size_t idx, uint8_t val)
    {
        container.setBits(idx * (Packed ? 1 : sizeof(VecElem)),
                (Packed ? 1 : sizeof(VecElem)), val);
    }
 
    template<typename VE2, size_t NE2, bool P2, bool C2>
    bool
    operator==(const VecPredRegT<VE2, NE2, P2, C2>& that) const
    {
        return container == that.container;
    }
 
    template<typename VE2, size_t NE2, bool P2, bool C2>
    bool
    operator!=(const VecPredRegT<VE2, NE2, P2, C2>& that) const
    {
        return !operator==(that);
    }
 
    friend std::ostream&
    operator<<(std::ostream& os, const MyClass& p)
    {
        // Size must be greater than 0.
        for (int i = 0; i < NUM_BITS; i++)
            ccprintf(os, "%s%d", i ? " " : "[", (int)p.container[i]);
        ccprintf(os, "]");
        return os;
    }
 
    template <bool MC>
    bool
    firstActive(const VecPredRegT<VecElem, NumElems, Packed, MC>& mask,
                size_t actual_num_elems) const
    {
        assert(actual_num_elems <= NumElems);
        for (int i = 0; i < actual_num_elems; ++i) {
            if (mask[i]) {
                return (*this)[i];
            }
        }
        return false;
    }
 
    template <bool MC>
    bool
    noneActive(const VecPredRegT<VecElem, NumElems, Packed, MC>& mask,
               size_t actual_num_elems) const
    {
        assert(actual_num_elems <= NumElems);
        for (int i = 0; i < actual_num_elems; ++i) {
            if (mask[i] && operator[](i)) {
                return false;
            }
        }
        return true;
    }
 
    template <bool MC>
    bool
    lastActive(const VecPredRegT<VecElem, NumElems, Packed, MC>& mask,
               size_t actual_num_elems) const
    {
        assert(actual_num_elems <= NumElems);
        for (int i = actual_num_elems - 1; i >= 0; --i) {
            if (mask[i]) {
                return operator[](i);
            }
        }
        return false;
    }
};
 
template <size_t NumBits, bool Packed>
class VecPredRegContainer
{
    static_assert(NumBits > 0,
                  "Size of a predicate register must be > 0");
 
  public:
    static constexpr size_t NUM_BITS = NumBits;
    using Container = std::array<bool, NumBits>;
 
  private:
    Container container;
    // Alias for this type
    using MyClass = VecPredRegContainer<NumBits, Packed>;
 
  public:
    VecPredRegContainer() {}
    VecPredRegContainer(const VecPredRegContainer &) = default;
 
    MyClass&
    operator=(const MyClass& that)
    {
        if (&that == this)
            return *this;
        container = that.container;
        return *this;
    }
 
    MyClass&
    operator=(const std::vector<uint8_t>& that)
    {
        assert(that.size() == NUM_BITS);
        std::copy(that.begin(), that.end(), container.begin());
        return *this;
    }
 
    void
    reset()
    {
        container.fill(false);
    }
 
    void
    set()
    {
        container.fill(true);
    }
 
    template<size_t N2, bool P2>
    inline bool
    operator==(const VecPredRegContainer<N2, P2>& that) const
    {
        return NumBits == N2 && Packed == P2 && container == that.container;
    }
 
    template<size_t N2, bool P2>
    bool
    operator!=(const VecPredRegContainer<N2, P2>& that) const
    {
        return !operator==(that);
    }
 
    bool& operator[](size_t idx) { return container[idx]; }
 
    const bool& operator[](size_t idx) const { return container[idx]; }
 
    uint8_t
    getBits(size_t idx, uint8_t nbits) const
    {
        assert(nbits > 0 && nbits <= 8 && (idx + nbits - 1) < NumBits);
        uint8_t v = 0;
        idx = idx + nbits - 1;
        for (int i = 0; i < nbits; ++i, --idx) {
            v <<= 1;
            v |= container[idx];
        }
        return v;
    }
 
    void
    setBits(size_t idx, uint8_t nbits, uint8_t bval)
    {
        assert(nbits > 0 && nbits <= 8 && (idx + nbits - 1) < NumBits);
        for (int i = 0; i < nbits; ++i, ++idx) {
            container[idx] = bval & 1;
            bval >>= 1;
        }
    }
 
    friend std::ostream&
    operator<<(std::ostream& os, const MyClass& p)
    {
        // Size must be greater than 0.
        for (int i = 0; i < NumBits; i++)
            ccprintf(os, "%s%d", i ? " " : "[", (int)p.container[i]);
        ccprintf(os, "]");
        return os;
    }
 
    friend ShowParam<VecPredRegContainer<NumBits, Packed>>;
 
    template <typename VecElem>
    VecPredRegT<VecElem, NumBits / sizeof(VecElem), Packed, true>
    as() const
    {
        static_assert(NumBits % sizeof(VecElem) == 0,
                "Container size incompatible with view size.");
        return VecPredRegT<VecElem, NumBits / sizeof(VecElem), Packed, true>(
                *this);
    }
 
    template <typename VecElem>
    VecPredRegT<VecElem, NumBits / sizeof(VecElem), Packed, false>
    as()
    {
        static_assert(NumBits % sizeof(VecElem) == 0,
                "Container size incompatible with view size.");
        return VecPredRegT<VecElem, NumBits / sizeof(VecElem), Packed, false>(
                *this);
    }
};
 
template <size_t NumBits, bool Packed>
struct ParseParam<VecPredRegContainer<NumBits, Packed>>
{
    static bool
    parse(const std::string &s, VecPredRegContainer<NumBits, Packed> &value)
    {
        int i = 0;
        for (const auto& c: s)
            value[i++] = (c == '1');
        return true;
    }
};
 
template <size_t NumBits, bool Packed>
struct ShowParam<VecPredRegContainer<NumBits, Packed>>
{
    static void
    show(std::ostream &os, const VecPredRegContainer<NumBits, Packed> &value)
    {
        for (auto b: value.container)
            ccprintf(os, "%d", b);
    }
};
 
using DummyVecPredRegContainer = VecPredRegContainer<8, false>;
 
} // namespace gem5
 
#endif  // __ARCH_GENERIC_VEC_PRED_REG_HH__