Lua: Don't lua_error() out of context with pending dtors

[lsnes.git] / src / library / memorysearch.cpp

#include "memoryspace.hpp"
#include "memorysearch.hpp"
#include "eatarg.hpp"
#include "minmax.hpp"
#include "serialization.hpp"
#include "int24.hpp"
#include <iostream>

memory_search::memory_search(memory_space& space) throw(std::bad_alloc)
        : mspace(space)
{
        candidates = 0;
}


struct search_update
{
        typedef uint8_t value_type;
        bool operator()(uint8_t oldv, uint8_t newv) const throw() { return true; }
};

template<typename T>
struct search_value
{
        typedef T value_type;
        search_value(T v) throw() { val = v; }
        bool operator()(T oldv, T newv) const throw() { return (newv == val); }
        T val;
};

template<typename T>
struct search_difference
{
        typedef T value_type;
        search_difference(T v) throw() { val = v; }
        bool operator()(T oldv, T newv) const throw() { return ((newv - oldv) == val); }
        T val;
};

template<typename T>
struct search_lt
{
        typedef T value_type;
        bool operator()(T oldv, T newv) const throw() { return (newv < oldv); }
};

template<typename T>
struct search_le
{
        typedef T value_type;
        bool operator()(T oldv, T newv) const throw() { return (newv <= oldv); }
};

template<typename T>
struct search_eq
{
        typedef T value_type;
        bool operator()(T oldv, T newv) const throw() { return (newv == oldv); }
};

template<typename T>
struct search_ne
{
        typedef T value_type;
        bool operator()(T oldv, T newv) const throw() { return (newv != oldv); }
};

template<typename T>
struct search_ge
{
        typedef T value_type;
        bool operator()(T oldv, T newv) const throw() { return (newv >= oldv); }
};

template<typename T>
struct search_gt
{
        typedef T value_type;
        bool operator()(T oldv, T newv) const throw() { return (newv > oldv); }
};

template<typename T>
struct search_seqlt
{
        typedef T value_type;
        bool operator()(T oldv, T newv) const throw()
        {
                T mask = (T)1 << (sizeof(T) * 8 - 1);
                T diff = newv - oldv;
                return ((diff & mask) != (T)0);
        }
};

template<typename T>
struct search_seqle
{
        typedef T value_type;
        bool operator()(T oldv, T newv) const throw()
        {
                T mask = (T)1 << (sizeof(T) * 8 - 1);
                T diff = newv - oldv;
                return ((diff & mask) != (T)0) || (diff == (T)0);
        }
};

template<typename T>
struct search_seqge
{
        typedef T value_type;
        bool operator()(T oldv, T newv) const throw()
        {
                T mask = (T)1 << (sizeof(T) * 8 - 1);
                T diff = newv - oldv;
                return ((diff & mask) == (T)0);
        }
};

template<typename T>
struct search_seqgt
{
        typedef T value_type;
        bool operator()(T oldv, T newv) const throw()
        {
                T mask = (T)1 << (sizeof(T) * 8 - 1);
                T diff = newv - oldv;
                return ((diff & mask) == (T)0) && (diff != (T)0);
        }
};


template<typename T>
struct search_value_helper
{
        typedef typename T::value_type value_type;
        search_value_helper(const T& v)  throw()
                : val(v)
        {
        }
        bool operator()(const uint8_t* newv, const uint8_t* oldv, uint64_t left, int endian) const throw()
        {
                if(left < sizeof(value_type))
                        return false;
                value_type v1 = serialization::read_endian<value_type>(oldv, endian);
                value_type v2 = serialization::read_endian<value_type>(newv, endian);
                return val(v1, v2);
        }
        const T& val;
};

namespace
{
        void dq_all_after(uint64_t* still_in, uint64_t& candidates, uint64_t size, uint64_t after)
        {
                for(uint64_t i = after; i < size; i++) {
                        if((still_in[i / 64] >> (i % 64)) & 1) {
                                still_in[i / 64] &= ~(1ULL << (i % 64));
                                candidates--;
                        }
                }
        }

        inline void dq_entry(uint64_t* still_in, uint64_t& candidates, uint64_t i)
        {
                if((still_in[i / 64] >> (i % 64)) & 1) {
                        still_in[i / 64] &= ~(1ULL << (i % 64));
                        candidates--;
                }
        }

        inline uint64_t next_multiple_of_64(uint64_t i)
        {
                return (i + 64) >> 6 << 6;
        }

        inline uint64_t prev_multiple_of_64(uint64_t i)
        {
                return ((i - 64) >> 6 << 6) + 63;
        }

        template<typename T>
        void search_block_mapped(uint64_t* still_in, uint64_t& candidates, memory_space::region& region,
                uint64_t rbase, uint64_t ibase, T& helper, std::vector<uint8_t>& previous_content)
        {
                if(ibase >= previous_content.size())
                        return;
                unsigned char* mem = region.direct_map;
                uint64_t rsize = region.size;
                int endian = region.endian;
                uint64_t i = ibase;
                uint64_t switch_at = ibase + rsize - rbase;     //The smallest i not in this region.
                rsize = min(rsize, previous_content.size() - ibase);
                for(unsigned j = rbase; j < rsize; i++, j++) {
                        //Advance blocks of 64 addresses if none of the addresses match.
                        while(still_in[i / 64] == 0 && next_multiple_of_64(i) <= switch_at) {
                                uint64_t old_i = i;
                                i = next_multiple_of_64(i);
                                j += i - old_i;
                        }
                        //This might match. Check it.
                        if(!helper(mem + j, &previous_content[i], rsize - j, endian))
                                dq_entry(still_in, candidates, i);
                }
        }

        template<typename T>
        void search_block_read(uint64_t* still_in, uint64_t& candidates, memory_space::region& region, uint64_t rbase,
                uint64_t ibase, T& helper, std::vector<uint8_t>& previous_content)
        {
                if(ibase >= previous_content.size())
                        return;
                uint64_t rsize = region.size;
                int endian = region.endian;
                uint64_t i = ibase;
                uint64_t switch_at = ibase + rsize - rbase;     //The smallest i not in this region.

                //The buffer.
                const size_t buffer_capacity = 4096;
                unsigned char buffer[buffer_capacity];
                uint64_t buffer_offset = 0;             //The offset in buffer.
                uint64_t buffer_remaining = 0;          //Number of bytes remaining in buffer.
                uint64_t buffer_soffset = rbase;        //The offset buffer start corresponds to.
                uint64_t buffer_eoffset = rbase;        //The first offset not in buffer.

                rsize = min(rsize, previous_content.size() - ibase);
                for(unsigned j = rbase; j < rsize; i++, j++) {
                        //Fill the buffer again if it has gotten low enough.
                        if(buffer_remaining < 256 && buffer_eoffset != rsize) {
                                if(buffer_remaining)
                                        memmove(buffer, buffer + buffer_offset, buffer_remaining);
                                buffer_offset = 0;
                                size_t fill_amount = min((uint64_t)buffer_capacity, rsize - buffer_eoffset);
                                region.read(buffer_eoffset, buffer + buffer_remaining, fill_amount);
                                buffer_eoffset += fill_amount;
                                buffer_remaining += fill_amount;
                        }
                        //Advance blocks of 64 addresses if none of the addresses match.
                        while(still_in[i / 64] == 0 && next_multiple_of_64(i) <= switch_at) {
                                uint64_t old_i = i;
                                i = next_multiple_of_64(i);
                                uint64_t advance = i - old_i;
                                j += advance;
                                buffer_offset += advance;
                                buffer_remaining -= advance;
                                buffer_soffset += advance;
                        }
                        //This might match. Check it.
                        if(!helper(buffer + buffer_offset, &previous_content[i], buffer_remaining, endian))
                                dq_entry(still_in, candidates, i);
                        buffer_offset++;
                        buffer_remaining--;
                        buffer_soffset++;
                }
        }

        void copy_block_mapped(uint8_t* old, memory_space::region& region, uint64_t rbase, uint64_t maxr)
        {
                memcpy(old, region.direct_map + rbase, min(region.size - rbase, maxr));
        }

        void copy_block_read(uint8_t* old, memory_space::region& region, uint64_t rbase, uint64_t maxr)
        {
                region.read(rbase, old, min(region.size - rbase, maxr));
        }

        void dq_block(uint64_t* still_in, uint64_t& candidates, memory_space::region& region, uint64_t rbase,
                uint64_t ibase, uint64_t first, uint64_t last, uint64_t ramsize)
        {
                if(ibase >= ramsize)
                        return;
                if(last < region.base + rbase || first >= region.base + region.size)
                        return;         //Nothing to DQ in this block.
                first = max(first, region.base + rbase) - region.base + rbase;
                last = last - region.base - rbase;
                last = min(last, ramsize - ibase);
                uint64_t ilast = ibase + last;
                for(uint64_t i = ibase + first; i <= ilast; i++) {
                        while(still_in[i / 64] == 0 && next_multiple_of_64(i) <= ilast) {
                                i = next_multiple_of_64(i);
                                continue;
                        }
                        dq_entry(still_in, candidates, i);
                }
        }

        void candidates_block(std::list<uint64_t>& out, memory_space::region& region, uint64_t rbase, uint64_t ibase,
                uint64_t* still_in, uint64_t ramsize)
        {
                if(ibase >= ramsize)
                        return;
                uint64_t rsize = region.size;
                uint64_t i = ibase;
                uint64_t switch_at = ibase + rsize - rbase;     //The smallest i not in this region.
                rsize = min(rsize, ramsize - ibase);
                for(unsigned j = rbase; j < rsize; i++, j++) {
                        //Advance blocks of 64 addresses if none of the addresses match.
                        while(still_in[i / 64] == 0 && next_multiple_of_64(i) <= switch_at) {
                                uint64_t old_i = i;
                                i = next_multiple_of_64(i);
                                j += i - old_i;
                        }
                        if((still_in[i / 64] >> (i % 64)) & 1)
                                out.push_back(region.base + j);
                }
        }

}

void memory_search::dq_range(uint64_t first, uint64_t last)
{
        auto t = mspace.lookup_linear(0);
        if(!t.first)
                return;
        uint64_t i = 0;
        uint64_t size = previous_content.size();
        while(true) {
                //Switch blocks.
                t = mspace.lookup_linear(i);
                if(!t.first) {
                        //DQ all rest.
                        dq_all_after(&still_in[0], candidates, size, i);
                        break;
                }
                dq_block(&still_in[0], candidates, *t.first, t.second, i, first, last, previous_content.size());
                i += t.first->size - t.second;
        }
}

template<class T> void memory_search::search(const T& obj) throw()
{
        search_value_helper<T> helper(obj);
        auto t = mspace.lookup_linear(0);
        if(!t.first)
                return;
        uint64_t size = previous_content.size();
        uint64_t i = 0;
        while(true) {
                //Switch blocks.
                t = mspace.lookup_linear(i);
                if(!t.first) {
                        //DQ all rest.
                        dq_all_after(&still_in[0], candidates, size, i);
                        break;
                }
                if(t.first->direct_map) {
                        search_block_mapped(&still_in[0], candidates, *t.first, t.second, i, helper,
                                previous_content);
                        copy_block_mapped(&previous_content[i], *t.first, t.second,
                                  max((uint64_t)previous_content.size(), i) - i);
                } else {
                        search_block_read(&still_in[0], candidates, *t.first, t.second, i, helper, previous_content);
                        copy_block_read(&previous_content[i], *t.first, t.second,
                                  max((uint64_t)previous_content.size(), i) - i);
                }
                i += t.first->size - t.second;
        }
}

template<typename T> void memory_search::s_value(T value) throw() { search(search_value<T>(value)); }
template<typename T> void memory_search::s_difference(T value) throw() { search(search_difference<T>(value)); }
template<typename T> void memory_search::s_lt() throw() { search(search_lt<T>()); }
template<typename T> void memory_search::s_le() throw() { search(search_le<T>()); }
template<typename T> void memory_search::s_eq() throw() { search(search_eq<T>()); }
template<typename T> void memory_search::s_ne() throw() { search(search_ne<T>()); }
template<typename T> void memory_search::s_ge() throw() { search(search_ge<T>()); }
template<typename T> void memory_search::s_gt() throw() { search(search_gt<T>()); }
template<typename T> void memory_search::s_seqlt() throw() { search(search_seqlt<T>()); }
template<typename T> void memory_search::s_seqle() throw() { search(search_seqle<T>()); }
template<typename T> void memory_search::s_seqge() throw() { search(search_seqge<T>()); }
template<typename T> void memory_search::s_seqgt() throw() { search(search_seqgt<T>()); }

template<typename T> T memory_search::v_read(uint64_t addr) throw() { return mspace.read<T>(addr); }
template<typename T> void memory_search::v_write(uint64_t addr, T val) throw() { mspace.write<T>(addr, val); }

template<typename T> T memory_search::v_readold(uint64_t addr) throw()
{
        uint64_t i = 0;
        auto t = mspace.lookup_linear(0);
        if(!t.first)
                return 0;
        //Search for linear range containing the address.
        while(true) {
                t = mspace.lookup_linear(i);
                if(!t.first)
                        return 0;
                if(t.first->base <= addr && t.first->base + t.first->size > addr) {
                        //Global address t.first->base <=> linear address i.
                        uint64_t linaddr = addr - t.first->base + i;
                        uint64_t maxr = t.first->size + t.first->base - addr;
                        maxr = min(maxr, (uint64_t)sizeof(T));
                        char buf[sizeof(T)] = {0};
                        if(previous_content.size() < linaddr + maxr)
                                return 0;
                        memcpy(buf, &previous_content[linaddr], maxr);
                        return serialization::read_endian<T>(buf, t.first->endian);
                }
                i += t.first->size - t.second;
        }
        return 0;
}

template<typename T> void memorysearch_pull_type(memory_search& s)
{
        eat_argument(&memory_search::s_value<T>);
        eat_argument(&memory_search::s_difference<T>);
        eat_argument(&memory_search::s_lt<T>);
        eat_argument(&memory_search::s_le<T>);
        eat_argument(&memory_search::s_eq<T>);
        eat_argument(&memory_search::s_ne<T>);
        eat_argument(&memory_search::s_ge<T>);
        eat_argument(&memory_search::s_gt<T>);
        eat_argument(&memory_search::s_seqlt<T>);
        eat_argument(&memory_search::s_seqle<T>);
        eat_argument(&memory_search::s_seqge<T>);
        eat_argument(&memory_search::s_seqgt<T>);
        eat_argument(&memory_search::v_read<T>);
        eat_argument(&memory_search::v_readold<T>);
        eat_argument(&memory_search::v_write<T>);
}

template<typename T> void memorysearch_pull_type2(memory_search& s)
{
        eat_argument(&memory_search::s_value<T>);
        eat_argument(&memory_search::s_difference<T>);
        eat_argument(&memory_search::s_lt<T>);
        eat_argument(&memory_search::s_le<T>);
        eat_argument(&memory_search::s_eq<T>);
        eat_argument(&memory_search::s_ne<T>);
        eat_argument(&memory_search::s_ge<T>);
        eat_argument(&memory_search::s_gt<T>);
        eat_argument(&memory_search::v_read<T>);
        eat_argument(&memory_search::v_readold<T>);
        eat_argument(&memory_search::v_write<T>);
}

void memorysearch_pull_all(memory_search& s)
{
        memorysearch_pull_type<int8_t>(s);
        memorysearch_pull_type<uint8_t>(s);
        memorysearch_pull_type<int16_t>(s);
        memorysearch_pull_type<uint16_t>(s);
        memorysearch_pull_type<ss_int24_t>(s);
        memorysearch_pull_type<ss_uint24_t>(s);
        memorysearch_pull_type<int32_t>(s);
        memorysearch_pull_type<uint32_t>(s);
        memorysearch_pull_type<int64_t>(s);
        memorysearch_pull_type<uint64_t>(s);
        memorysearch_pull_type2<float>(s);
        memorysearch_pull_type2<double>(s);
}

void memory_search::update() throw() { search(search_update()); }

uint64_t memory_search::get_candidate_count() throw()
{
        return candidates;
}

std::list<uint64_t> memory_search::get_candidates() throw(std::bad_alloc)
{
        std::list<uint64_t> out;
        auto t = mspace.lookup_linear(0);
        if(!t.first)
                return out;
        uint64_t i = 0;
        while(true) {
                //Switch blocks.
                t = mspace.lookup_linear(i);
                if(!t.first)
                        return out;
                candidates_block(out, *t.first, t.second, i, &still_in[0], previous_content.size());
                i += t.first->size - t.second;
        }
        return out;
}

bool memory_search::is_candidate(uint64_t addr) throw()
{
        auto t = mspace.lookup_linear(0);
        if(!t.first)
                return false;
        uint64_t i = 0;
        while(true) {
                //Switch blocks.
                t = mspace.lookup_linear(i);
                if(!t.first)
                        return false;
                if(i >= previous_content.size())
                        return false;
                uint64_t rsize = t.first->size;
                rsize = min(rsize, previous_content.size() - i);
                if(addr >= t.first->base + t.second && addr < t.first->base + rsize) {
                        uint64_t adv = addr - (t.first->base + t.second);
                        uint64_t ix = i + adv;
                        return ((still_in[ix / 64] >> (ix % 64)) & 1);
                }
                i += t.first->size - t.second;
        }
        return false;
}

uint64_t memory_search::cycle_candidate_vma(uint64_t addr, bool next) throw()
{
        auto t = mspace.lookup_linear(0);
        if(!t.first)
                return false;
        uint64_t i = 0;
        while(true) {
                //Switch blocks.
                t = mspace.lookup_linear(i);
                if(!t.first)
                        return addr;
                if(i >= previous_content.size())
                        return addr;
                uint64_t rsize = t.first->size;
                int64_t switch_at = i + rsize - t.second;       //The smallest i not in this region.
                rsize = min(rsize, previous_content.size() - i);
                if(addr >= t.first->base + t.second && addr < t.first->base + rsize) {
                        uint64_t baseaddr = t.first->base + t.second;
                        int64_t tryoff = addr - baseaddr + i;
                        int64_t finoff = tryoff;
                        int64_t warp = i;
                        bool warped = false;
                        if(next) {
                                //Cycle forwards.
                                tryoff++;
                                while(tryoff < finoff || !warped) {
                                        if(tryoff >= switch_at) {
                                                tryoff = warp;
                                                if(warped)
                                                        return addr;
                                                warped = true;
                                        }
                                        if(still_in[tryoff / 64] == 0)
                                                tryoff = next_multiple_of_64(tryoff);
                                        else {
                                                if((still_in[tryoff / 64] >> (tryoff % 64)) & 1)
                                                        return tryoff - i + baseaddr;
                                                tryoff++;
                                        }
                                }
                        } else {
                                //Cycle backwards.
                                tryoff--;
                                while(tryoff > finoff || !warped) {
                                        if(tryoff < warp) {
                                                tryoff = switch_at - 1;
                                                if(warped)
                                                        return addr;
                                                warped = true;
                                        }
                                        if(still_in[tryoff / 64] == 0)
                                                tryoff = prev_multiple_of_64(tryoff);
                                        else {
                                                if((still_in[tryoff / 64] >> (tryoff % 64)) & 1)
                                                        return tryoff - i + baseaddr;
                                                tryoff--;
                                        }
                                }
                        }
                }
                i += t.first->size - t.second;
        }
        return addr;
}

void memory_search::reset() throw(std::bad_alloc)
{
        uint64_t linearram = mspace.get_linear_size();
        previous_content.resize(linearram);
        still_in.resize((linearram + 63) / 64);
        for(uint64_t i = 0; i < linearram / 64; i++)
                still_in[i] = 0xFFFFFFFFFFFFFFFFULL;
        if(linearram % 64)
                still_in[linearram / 64] = (1ULL << (linearram % 64)) - 1;
        candidates = linearram;

        auto t = mspace.lookup_linear(0);
        if(!t.first)
                return;
        uint64_t i = 0;
        while(true) {
                //Switch blocks.
                t = mspace.lookup_linear(i);
                if(!t.first)
                        break;
                if(t.first->direct_map)
                        copy_block_mapped(&previous_content[i], *t.first, t.second,
                                max((uint64_t)previous_content.size(), i) - i);
                else
                        copy_block_read(&previous_content[i], *t.first, t.second,
                                max((uint64_t)previous_content.size(), i) - i);
                i += t.first->size - t.second;
        }
}


void memory_search::savestate(std::vector<char>& buffer, enum savestate_type type) const
{
        size_t size;
        uint64_t linsize = mspace.get_linear_size();
        if(type == ST_PREVMEM)
                size = 9 + linsize;
        else if(type == ST_SET)
                size = 17 + (linsize + 63) / 64 * 8;
        else if(type == ST_ALL)
                size = 17 + linsize + (linsize + 63) / 64 * 8;
        else
                throw std::runtime_error("Invalid savestate type");
        buffer.resize(size);
        buffer[0] = type;
        serialization::u64b(&buffer[1], linsize);
        size_t offset = 9;
        if(type == ST_PREVMEM || type == ST_ALL) {
                memcpy(&buffer[offset], &previous_content[0], min(linsize, (uint64_t)previous_content.size()));
                offset += linsize;
        }
        if(type == ST_SET || type == ST_ALL) {
                serialization::u64b(&buffer[offset], candidates);
                offset += 8;
                size_t bound = min((linsize + 63) / 64, (uint64_t)still_in.size());
                for(unsigned i = 0; i < bound; i++) {
                        serialization::u64b(&buffer[offset], still_in[i]);
                        offset += 8;
                }
        }
}

void memory_search::loadstate(const std::vector<char>& buffer)
{
        if(buffer.size() < 9 || buffer[0] < ST_PREVMEM || buffer[0] > ST_ALL)
                throw std::runtime_error("Invalid memory search save");
        uint64_t linsize = serialization::u64b(&buffer[1]);
        if(linsize != mspace.get_linear_size())
                throw std::runtime_error("Save size mismatch (not from this game)");
        if(!previous_content.size())
                reset();
        savestate_type type = (savestate_type)buffer[0];
        size_t offset = 9;
        if(type == ST_PREVMEM || type == ST_ALL) {
                memcpy(&previous_content[0], &buffer[offset], min(linsize, (uint64_t)previous_content.size()));
                offset += linsize;
        }
        if(type == ST_SET || type == ST_ALL) {
                candidates = serialization::u64b(&buffer[offset]);
                offset += 8;
                size_t bound = min((linsize + 63) / 64, (uint64_t)still_in.size());
                for(unsigned i = 0; i < bound; i++) {
                        still_in[i] = serialization::u64b(&buffer[offset]);
                        offset += 8;
                }
        }
}