eden/src/shader_recompiler/frontend/maxwell/decode.cpp

// SPDX-FileCopyrightText: Copyright 2026 Eden Emulator Project
// SPDX-License-Identifier: GPL-3.0-or-later
// SPDX-FileCopyrightText: Copyright 2021 yuzu Emulator Project
// SPDX-License-Identifier: GPL-2.0-or-later

#include <algorithm>
#include <array>
#include <bit>
#include <memory>
#include <ranges>
#include <string_view>

#include "common/assert.h"
#include "common/common_types.h"
#include "shader_recompiler/exception.h"
#include "shader_recompiler/frontend/maxwell/decode.h"
#include "shader_recompiler/frontend/maxwell/opcodes.h"

namespace Shader::Maxwell {

consteval std::pair<u64, u64> MaskValueFromEncoding(const char data[20]) noexcept {
    u64 mask = 0, value = 0, bit = u64(1) << 63;
    for (int i = 0; i < 20; ++i)
        switch (data[i]) {
        case '0':
            mask |= bit;
            bit >>= 1;
            break;
        case '1':
            mask |= bit;
            value |= bit;
            bit >>= 1;
            break;
        case '-':
            bit >>= 1;
            break;
        default:
            break;
        }
    return { mask, value };
}

Opcode Decode(u64 insn) {
#define INST(name, cute, encode) \
    if (auto const p = MaskValueFromEncoding(encode); (insn & p.first) == p.second) \
        return Opcode::name;
#include "maxwell.inc"
#undef INST
    ASSERT_MSG(false, "Invalid insn {:#016x}", insn);
    return Opcode::NOP;
}

} // namespace Shader::Maxwell