memory_arena.h

/*
 * cugar
 * Copyright (c) 2011-2018, NVIDIA CORPORATION. All rights reserved.
 * 
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 * modification, are permitted provided that the following conditions are met:
 *    * Redistributions of source code must retain the above copyright
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 *    * Redistributions in binary form must reproduce the above copyright
 *      notice, this list of conditions and the following disclaimer in the
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 *      names of its contributors may be used to endorse or promote products
 *      derived from this software without specific prior written permission.
 * 
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 */

#pragma once

#include <cugar/basic/types.h>
#include <cugar/basic/numbers.h>

namespace cugar {



struct memory_arena
{
    CUGAR_HOST_DEVICE
    memory_arena(uint8* _ptr = NULL) : ptr(_ptr), size(0u) {}

    CUGAR_HOST_DEVICE
    uint8* byte_alloc(const uint64 sz, const uint64 alignment = 1u)
    {
        const uint64 base = round_i(size, alignment);
        size = base + sz;
        return ptr + base;
    }

    template <typename T>
    CUGAR_HOST_DEVICE
    T* alloc(const uint64 sz, const uint64 alignment = sizeof(T))
    {
        return (T*)byte_alloc(sz * sizeof(T), alignment);
    }

    uint8*  ptr;
    uint64  size;
};


} // namespace cugar