From 08ea92908437518a0223368776aa920442d2f0d4 Mon Sep 17 00:00:00 2001
From: tovjemam <zbyvaj@seznam.cz>
Date: Sat, 22 Nov 2025 19:36:26 +0100
Subject: [PATCH] New era

---
 .clang-format  |   2 +
 .gitignore     |   1 +
 main.cpp       |  71 +++++++++++++++++---
 mp/int.hpp     |  97 ++++++++++++++++++++++++++++
 mp/math.hpp    | 172 +++++++++++++++++++++++++++++++++++++++++++++++++
 mp/storage.hpp |  74 +++++++++++++++++++++
 mp/utils.hpp   | 150 ++++++++++++++++++++++++++++++++++++++++++
 7 files changed, 558 insertions(+), 9 deletions(-)
 create mode 100644 mp/int.hpp
 create mode 100644 mp/math.hpp
 create mode 100644 mp/storage.hpp
 create mode 100644 mp/utils.hpp

diff --git a/.clang-format b/.clang-format
index 06546a8..0f3b668 100644
--- a/.clang-format
+++ b/.clang-format
@@ -4,3 +4,5 @@ PointerAlignment: Left
 IndentWidth: 4        # spaces per indent level
 TabWidth: 4           # width of a tab character
 UseTab: Never         # options: Never, ForIndentation, Alwayss
+BreakTemplateDeclarations: Yes
+AllowShortFunctionsOnASingleLine: Inline
diff --git a/.gitignore b/.gitignore
index e524d79..24e741c 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,2 +1,3 @@
 .vscode/
+.vs/
 build/
diff --git a/main.cpp b/main.cpp
index 3bab47f..fc93991 100644
--- a/main.cpp
+++ b/main.cpp
@@ -1,31 +1,84 @@
 #include <iostream>
 
-#include "mp.hpp"
+//#include "mp.hpp"
+#include "mp/int.hpp"
+#include "mp/storage.hpp"
+#include "mp/math.hpp"
 
 template <class T>
 static void PrintInt(const char* name, const T& val)
 {
-    std::cout << name << " = " << mp::ToHexString(val) << std::endl;
+    std::cout << name << " = " << mp::to_hex_string(val) << std::endl;
 }
 
 int main()
 {
     // mp::Int a{0xDEADBEEFDEADF154, 0x0123456789ABCDEF, 0x1111222233334444};
-    mp::Int<4> a{0xFFFFFFFFFFFFFFFF, 0xFFFFFFFFFFFFFFFF};
-    mp::Int<5> b{0x55};
+    mp::Int<32> a{0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF};
+    mp::Int<1> b{0x55};
     
     PrintInt("a", a);
     PrintInt("b", b);
     
     auto c = a + b;
+    //auto c = binary_opa, b);
     PrintInt("c", c);
     
-    a += mp::Int<1>{1};
-    PrintInt("a", a);
+    //a += mp::Int<1>{1};
+    //PrintInt("a", a);
     
-    a -= mp::Int<1>{1};
-    PrintInt("a", a);
+    //a -= mp::Int<1>{1};
+    //PrintInt("a", a);
 
-    std::cout << mp::Int<16>::LAST_ELEM_MASK << std::endl;
+    std::cout << mp::Int<17>::LAST_ELEM_MASK << std::endl;
 
+    std::cout << sizeof(mp::Int<1>) << std::endl;
+    std::cout << sizeof(mp::Int<2>) << std::endl;
+    std::cout << sizeof(mp::Int<3>) << std::endl;
+    std::cout << sizeof(mp::Int<4>) << std::endl;
+    std::cout << sizeof(mp::Int<5>) << std::endl;
+    std::cout << sizeof(mp::Int<6>) << std::endl;
+    std::cout << sizeof(mp::Int<7>) << std::endl;
+    std::cout << sizeof(mp::Int<8>) << std::endl;
+    std::cout << sizeof(mp::Int<9>) << std::endl;
+    std::cout << sizeof(mp::Int<10>) << std::endl;
+    std::cout << sizeof(mp::Int<20>) << std::endl;
+    std::cout << sizeof(mp::Int<30>) << std::endl;
+    std::cout << sizeof(mp::Int<40>) << std::endl;
+    std::cout << sizeof(mp::Int<50>) << std::endl;
+    std::cout << sizeof(mp::Int<60>) << std::endl;
+    std::cout << sizeof(mp::Int<70>) << std::endl;
+    std::cout << sizeof(mp::Int<80>) << std::endl;
+    std::cout << sizeof(mp::Int<90>) << std::endl;
+    std::cout << sizeof(mp::Int<100>) << std::endl;
+    std::cout << sizeof(mp::Int<110>) << std::endl;
+    std::cout << sizeof(mp::Int<120>) << std::endl;
+    std::cout << sizeof(mp::Int<130>) << std::endl;
+    std::cout << sizeof(mp::Int<140>) << std::endl;
+    std::cout << sizeof(mp::Int<150>) << std::endl;
+    std::cout << sizeof(mp::Int<160>) << std::endl;
+
+
+
+    {
+        mp::Int<1024> acc{1};
+
+        try
+        {
+            while (true)
+            {
+                acc *= mp::Int<1>{10};
+                PrintInt("acc", acc);
+            }
+        }
+        catch (const mp::OverflowErrorOf<decltype(acc), mp::Int<1>>& e)
+        {
+            std::cout << "overflow" << std::endl;
+            PrintInt("value", e.value());
+        }
+        catch (const std::exception& e)
+        {
+            std::cout << "error: " << e.what() << std::endl;
+        }
+    }
 }
\ No newline at end of file
diff --git a/mp/int.hpp b/mp/int.hpp
new file mode 100644
index 0000000..2f5eca8
--- /dev/null
+++ b/mp/int.hpp
@@ -0,0 +1,97 @@
+#pragma once
+
+#include <ranges>
+
+#include "utils.hpp"
+#include "storage.hpp"
+
+namespace mp
+{
+
+template <ElementSuitable TElem, size_t MaxBytes>
+class BasicInt
+{
+  public:
+    using ElementType = TElem;
+    constexpr static size_t MAX_BYTES = MaxBytes;
+    constexpr static size_t ELEMENT_BYTES = sizeof(TElem);
+    constexpr static size_t MAX_ELEMS = (MAX_BYTES + ELEMENT_BYTES - 1) / ELEMENT_BYTES;
+    constexpr static TElem LAST_ELEM_MASK = calculate_last_elem_mask<TElem, MAX_BYTES>();
+
+    BasicInt() = default;
+
+    BasicInt(std::initializer_list<ElementType> init)
+    {
+        for (size_t i = 0; i < init.size(); ++i)
+        {
+            set(i, *(init.begin() + i));
+        }
+    }
+
+    TElem& operator[](size_t index) { return m_data[index]; }
+    const TElem& operator[](size_t index) const { return m_data[index]; }
+
+    void resize(size_t new_size)
+    {
+        m_data.resize(new_size);
+    }
+
+    void zero() { m_data.clear(); }
+
+    bool try_set(size_t idx, TElem value)
+    {
+        if (idx >= m_data.size())
+        {
+            if (value == 0)
+            {
+                return true;
+            }
+
+            if (idx >= MAX_ELEMS)
+            {
+                return false;
+            }
+
+            m_data.resize(idx + 1);
+        }
+
+        m_data[idx] = value;
+
+        if (idx == MAX_ELEMS - 1 && value > LAST_ELEM_MASK)
+        {
+            m_data[idx] &= LAST_ELEM_MASK;
+            return false;
+        }
+
+        return true;
+    }
+
+    void set(size_t idx, TElem value)
+    {
+        if (!try_set(idx, value))
+        {
+            throw std::out_of_range("Value exceeds maximum size");
+        }
+    }
+
+    TElem get(size_t idx) const
+    {
+        if (idx >= m_data.size())
+        {
+            return TElem{0};
+        }
+        return m_data[idx];
+    }
+
+    //std::span<TElem> data() { return m_data; }
+
+    size_t size_elems() const { return m_data.size(); }
+
+  private:
+    Container<TElem, MAX_ELEMS> m_data;
+};
+
+template<size_t MaxBytes>
+using Int = BasicInt<LongestElementSuitableType, MaxBytes>;
+
+} // namespace mp
\ No newline at end of file
diff --git a/mp/math.hpp b/mp/math.hpp
new file mode 100644
index 0000000..99f5d9a
--- /dev/null
+++ b/mp/math.hpp
@@ -0,0 +1,172 @@
+#pragma once
+
+#include "int.hpp"
+#include "storage.hpp"
+#include "utils.hpp"
+
+namespace mp
+{
+
+template <size_t SizeA, size_t SizeB>
+constexpr size_t ResultMaxSize = std::max(SizeA, SizeB);
+
+template <AnyInt TLhs, AnyInt TRhs>
+    requires ElementTypesMatch<TLhs, TRhs>
+using OpResult = BasicInt<typename TLhs::ElementType, ResultMaxSize<TLhs::MAX_BYTES, TRhs::MAX_BYTES>>;
+
+template <AnyInt T>
+class OverflowError : public std::runtime_error
+{
+  public:
+    OverflowError(T&& value) : std::runtime_error("Overflow"), m_value(std::move(value)) {}
+
+    const T& value() const { return m_value; }
+
+  private:
+    T m_value;
+};
+
+template <AnyInt TLhs, AnyInt TRhs>
+using OverflowErrorOf = OverflowError<OpResult<TLhs, TRhs>>;
+
+struct Addition
+{
+    template <AnyInt TLhs, AnyInt TRhs, AnyInt TRes>
+        requires ElementTypesMatch<TLhs, TRes> && ElementTypesMatch<TRhs, TRes>
+    static void invoke(const TLhs& lhs, const TRhs& rhs, TRes& res)
+    {
+        using ElementType = typename TRes::ElementType;
+
+        res.zero();
+
+        ElementType carry = 0;
+        size_t end = std::max(lhs.size_elems(), rhs.size_elems());
+
+        for (size_t i = 0; i < end; ++i)
+        {
+            ElementType a = lhs.get(i);
+            ElementType b = rhs.get(i);
+
+            ElementType c = carry + a;
+            carry = (c < a) ? 1 : 0;
+            c += b;
+            if (c < b)
+                carry = 1;
+
+            res.set(i, c);
+        }
+
+        res.set(end, carry);
+    }
+};
+
+struct Multiplication
+{
+    template <AnyInt TLhs, AnyInt TRhs, AnyInt TRes>
+        requires ElementTypesMatch<TLhs, TRes> && ElementTypesMatch<TRhs, TRes>
+    static void invoke(const TLhs& lhs, const TRhs& rhs, TRes& res)
+    {
+        using ElementType = typename TRes::ElementType;
+        using DoubleType = DoubleWidthType<ElementType>;
+
+        res.zero();
+
+        bool overflow = false;
+
+        const size_t n = lhs.size_elems();
+        const size_t m = rhs.size_elems();
+
+        for (size_t i = 0; i < n; i++)
+        {
+            DoubleType carry = 0;
+            ElementType a = lhs[i];
+            for (size_t j = 0; j < m; j++)
+            {
+                ElementType b = rhs[j];
+                DoubleType t = static_cast<DoubleType>(a) * b + res.get(i + j) + carry;
+
+                overflow |= !res.try_set(i + j, static_cast<ElementType>(t));
+                carry = t >> (sizeof(ElementType) * 8);
+            }
+            overflow |= !res.try_set(i + m, static_cast<ElementType>(carry));
+        }
+
+        if (overflow)
+        {
+            throw std::overflow_error("Multiplication overflow");
+        }
+    };
+};
+
+// Binary operation
+template <typename TOp, AnyInt TLhs, AnyInt TRhs>
+    requires ElementTypesMatch<TLhs, TRhs>
+OpResult<TLhs, TRhs> binary_op(const TLhs& lhs, const TRhs& rhs)
+{
+    OpResult<TLhs, TRhs> res{};
+
+    try
+    {
+        TOp::invoke(lhs, rhs, res);
+    }
+    catch (const std::overflow_error&)
+    {
+        throw OverflowErrorOf<TLhs, TRhs>(std::move(res));
+    }
+
+    return res;
+}
+
+// Compound assignment binary operation
+template <typename TOp, AnyInt TLhs, AnyInt TRhs>
+    requires ElementTypesMatch<TLhs, TRhs>
+TLhs& ca_binary_op(TLhs& lhs, const TRhs& rhs)
+{
+    TLhs res{};
+
+    try
+    {
+        TOp::invoke(lhs, rhs, res);
+    }
+    catch (const std::overflow_error&)
+    {
+        throw OverflowErrorOf<TLhs, TRhs>(std::move(res));
+    }
+
+    lhs = std::move(res);
+    return lhs;
+}
+
+// Addition operators
+
+template <AnyInt TLhs, AnyInt TRhs>
+    requires ElementTypesMatch<TLhs, TRhs>
+OpResult<TLhs, TRhs> operator+(const TLhs& lhs, const TRhs& rhs)
+{
+    return binary_op<Addition>(lhs, rhs);
+}
+
+template <AnyInt TLhs, AnyInt TRhs>
+    requires ElementTypesMatch<TLhs, TRhs>
+TLhs& operator+=(TLhs& lhs, const TRhs& rhs)
+{
+    return ca_binary_op<Addition>(lhs, rhs);
+}
+
+// Multiplication operators
+
+template <AnyInt TLhs, AnyInt TRhs>
+    requires ElementTypesMatch<TLhs, TRhs>
+OpResult<TLhs, TRhs> operator*(const TLhs& lhs, const TRhs& rhs)
+{
+    return binary_op<Multiplication>(lhs, rhs);
+}
+
+template <AnyInt TLhs, AnyInt TRhs>
+    requires ElementTypesMatch<TLhs, TRhs>
+TLhs& operator*=(TLhs& lhs, const TRhs& rhs)
+{
+    return ca_binary_op<Multiplication>(lhs, rhs);
+}
+
+} // namespace mp
\ No newline at end of file
diff --git a/mp/storage.hpp b/mp/storage.hpp
new file mode 100644
index 0000000..697166c
--- /dev/null
+++ b/mp/storage.hpp
@@ -0,0 +1,74 @@
+#pragma once
+
+#include <array>
+#include <concepts>
+#include <cstddef>
+#include <span>
+#include <stdexcept>
+#include <vector>
+
+#include "utils.hpp"
+
+namespace mp
+{
+
+template <typename TElem, size_t MaxSize>
+class ArrayContainer
+{
+  public:
+    ArrayContainer() = default;
+
+    TElem& operator[](size_t idx) { return m_data[idx]; }
+    const TElem& operator[](size_t idx) const { return m_data[idx]; }
+
+    size_t size() const { return m_size; }
+    void clear() { m_size = 0; }
+
+    void resize(size_t new_size)
+    {
+        if (new_size > MaxSize)
+            throw std::out_of_range("New size exceeds maximum number of elements");
+
+        if (new_size > m_size)
+            std::fill(m_data.begin() + m_size, m_data.begin() + new_size, TElem{0});
+
+        m_size = new_size;
+    }
+
+  private:
+    size_t m_size = 0;
+    std::array<TElem, MaxSize> m_data;
+};
+
+template <typename TElem, size_t MaxSize>
+class VectorContainer
+{
+  public:
+    VectorContainer() = default;
+
+    TElem& operator[](size_t idx) { return m_data[idx]; }
+    const TElem& operator[](size_t idx) const { return m_data[idx]; }
+
+    size_t size() const { return m_data.size(); }
+    void clear() { m_data.clear(); }
+
+    void resize(size_t new_size)
+    {
+        if (new_size > MaxSize)
+            throw std::out_of_range("New size exceeds maximum number of elements");
+
+        m_data.resize(new_size, TElem{0});
+    }
+
+  private:
+    std::vector<TElem> m_data;
+};
+
+// threshold for self-contained storage
+constexpr size_t MAX_ARRAY_BYTES = 128;
+
+template <typename TElem, size_t MaxSize>
+using Container =
+    std::conditional_t<(sizeof(TElem) * MaxSize > MAX_ARRAY_BYTES), VectorContainer<TElem, MaxSize>, ArrayContainer<TElem, MaxSize>>;
+
+} // namespace mp
\ No newline at end of file
diff --git a/mp/utils.hpp b/mp/utils.hpp
new file mode 100644
index 0000000..868be88
--- /dev/null
+++ b/mp/utils.hpp
@@ -0,0 +1,150 @@
+#pragma once
+
+#include <concepts>
+#include <cstdint>
+#include <type_traits>
+
+namespace mp
+{
+
+//======================== DoubleWidthType =======================//
+
+template <typename T>
+struct DoubleWidth;
+
+template <>
+struct DoubleWidth<uint8_t>
+{
+    using type = uint16_t;
+};
+
+template <>
+struct DoubleWidth<uint16_t>
+{
+    using type = uint32_t;
+};
+
+template <>
+struct DoubleWidth<uint32_t>
+{
+    using type = uint64_t;
+};
+
+#ifdef __SIZEOF_INT128__
+template <>
+struct DoubleWidth<uint64_t>
+{
+    using type = __uint128_t;
+};
+#endif
+
+template <typename T>
+using DoubleWidthType = typename DoubleWidth<T>::type;
+
+//======================== HalfWidthType =======================//
+
+template <typename T>
+struct HalfWidth;
+
+template <>
+struct HalfWidth<uint16_t>
+{
+    using type = uint8_t;
+};
+
+template <>
+struct HalfWidth<uint32_t>
+{
+    using type = uint16_t;
+};
+
+template <>
+struct HalfWidth<uint64_t>
+{
+    using type = uint32_t;
+};
+
+template <typename T>
+using HalfWidthType = typename HalfWidth<T>::type;
+
+//======================== Concepts =======================//
+
+template <typename T>
+concept ElementSuitable = std::unsigned_integral<T>;
+
+template <typename T, typename TElem = T::ElementType>
+concept AnyInt = requires(T t, TElem a, size_t i) {
+    { t[i] } -> std::convertible_to<TElem>;
+    { t.set(i, a) };
+    { t.try_set(i, a) } -> std::convertible_to<bool>;
+    { t.get(i) } -> std::convertible_to<TElem>;
+    { t.zero() };
+    { t.size_elems() } -> std::convertible_to<size_t>;
+    { T::MAX_BYTES } -> std::convertible_to<size_t>;
+    { T::MAX_ELEMS } -> std::convertible_to<size_t>;
+    { T::ELEMENT_BYTES } -> std::convertible_to<size_t>;
+    { T::LAST_ELEM_MASK } -> std::convertible_to<TElem>;
+};
+
+//======================== Utils =======================//
+
+#ifdef __SIZEOF_INT128__
+using LongestElementSuitableType = uint64_t;
+#else
+using LongestElementSuitableType = HalfWidthType<size_t>;
+#endif
+
+template <AnyInt TA, AnyInt TB>
+constexpr bool ElementTypesMatch = std::is_same_v<typename TA::ElementType, typename TB::ElementType>;
+
+template <ElementSuitable TElem, size_t MaxBytes>
+constexpr TElem calculate_last_elem_mask()
+{
+    size_t last_elem_bytes = MaxBytes % sizeof(TElem);
+    TElem mask = 0;
+
+    if (last_elem_bytes == 0)
+    {
+        return ~mask;
+    }
+
+    for (size_t i = 0; i < last_elem_bytes; ++i)
+    {
+        mask <<= 8;
+        mask |= 0xFF;
+    }
+    return mask;
+}
+
+inline char hex_digit(uint8_t bits)
+{
+    return bits > 9 ? 'a' + (bits - 10) : '0' + bits;
+}
+
+template <AnyInt T>
+std::string to_hex_string(const T& number)
+{
+    constexpr size_t ELEMENT_DIGITS = T::ELEMENT_BYTES * 2;
+
+    std::string str(number.size_elems() * ELEMENT_DIGITS, '-');
+
+    for (size_t elem = 0; elem < number.size_elems(); ++elem)
+    {
+        auto v = number[elem];
+        for (size_t digit = 0; digit < ELEMENT_DIGITS; ++digit)
+        {
+            str[str.size() - 1 - (elem * ELEMENT_DIGITS) - digit] = hex_digit((v >> (digit * 4)) & 0xF);
+        }
+    }
+
+    auto first = str.find_first_not_of('0');
+    if (first != std::string::npos)
+    {
+        return "0x" + str.substr(first);
+    }
+
+    return "0x0";
+
+}
+
+}
\ No newline at end of file