rustorch 0.6.29

//! Hardware-specific optimizations
//! ハードウェア特化最適化

use crate::error::{RusTorchError, RusTorchResult};
use std::collections::HashMap;

/// Hardware accelerator types
/// ハードウェアアクセラレータタイプ
#[derive(Debug, Clone, Copy, PartialEq)]
pub enum AcceleratorType {
    /// CPU only
    CPU,
    /// NVIDIA GPU (CUDA)
    CUDA,
    /// AMD GPU (ROCm)
    ROCm,
    /// Intel GPU (oneAPI)
    OneAPI,
    /// Apple Silicon GPU (Metal)
    Metal,
    /// Custom accelerator
    Custom,
}

/// Hardware capabilities
/// ハードウェア機能
#[derive(Debug, Clone)]
pub struct HardwareCapabilities {
    /// Available accelerators
    pub accelerators: Vec<AcceleratorInfo>,
    /// CPU information
    pub cpu_info: CpuInfo,
    /// Memory hierarchy
    pub memory_hierarchy: MemoryHierarchy,
    /// Interconnect bandwidth
    pub interconnect_bandwidth: f64,
    /// Power constraints
    pub power_budget: Option<f64>,
}

/// Accelerator information
/// アクセラレータ情報
#[derive(Debug, Clone)]
pub struct AcceleratorInfo {
    /// Accelerator type
    pub accel_type: AcceleratorType,
    /// Device name
    pub name: String,
    /// Number of compute units
    pub compute_units: usize,
    /// Clock frequency (MHz)
    pub clock_freq: usize,
    /// Memory size (bytes)
    pub memory_size: usize,
    /// Memory bandwidth (GB/s)
    pub memory_bandwidth: f64,
    /// Compute capability (TFLOPS)
    pub compute_capability: f64,
    /// Device ID
    pub device_id: usize,
}

/// CPU information
/// CPU情報
#[derive(Debug, Clone)]
pub struct CpuInfo {
    /// Vendor (Intel, AMD, ARM, etc.)
    pub vendor: String,
    /// Model name
    pub model: String,
    /// Number of physical cores
    pub physical_cores: usize,
    /// Number of logical cores
    pub logical_cores: usize,
    /// Base frequency (MHz)
    pub base_freq: usize,
    /// Turbo frequency (MHz)
    pub turbo_freq: Option<usize>,
    /// Instruction set extensions
    pub extensions: Vec<String>,
}

/// Memory hierarchy information
/// メモリ階層情報
#[derive(Debug, Clone)]
pub struct MemoryHierarchy {
    /// L1 cache size (bytes)
    pub l1_cache: usize,
    /// L2 cache size (bytes)
    pub l2_cache: usize,
    /// L3 cache size (bytes)
    pub l3_cache: Option<usize>,
    /// Main memory size (bytes)
    pub main_memory: usize,
    /// Memory latencies (cycles)
    pub latencies: HashMap<String, usize>,
}

/// Hardware optimizer
/// ハードウェア最適化器
pub struct HardwareOptimizer {
    capabilities: HardwareCapabilities,
    selected_accelerator: Option<AcceleratorInfo>,
    optimization_strategy: OptimizationStrategy,
}

/// Optimization strategies
/// 最適化戦略
#[derive(Debug, Clone, Copy)]
enum OptimizationStrategy {
    /// Optimize for latency
    MinimizeLatency,
    /// Optimize for throughput
    MaximizeThroughput,
    /// Optimize for power efficiency
    PowerEfficient,
    /// Balanced optimization
    Balanced,
}

impl HardwareOptimizer {
    /// Create new hardware optimizer
    /// 新規ハードウェア最適化器作成
    pub fn new() -> Self {
        let capabilities = Self::detect_hardware();
        let selected_accelerator = Self::select_best_accelerator(&capabilities);

        HardwareOptimizer {
            capabilities,
            selected_accelerator,
            optimization_strategy: OptimizationStrategy::Balanced,
        }
    }

    /// Detect hardware capabilities
    /// ハードウェア機能検出
    fn detect_hardware() -> HardwareCapabilities {
        let cpu_info = Self::detect_cpu_info();
        let accelerators = Self::detect_accelerators();
        let memory_hierarchy = Self::detect_memory_hierarchy();

        HardwareCapabilities {
            accelerators,
            cpu_info,
            memory_hierarchy,
            interconnect_bandwidth: Self::measure_interconnect_bandwidth(),
            power_budget: Self::detect_power_constraints(),
        }
    }

    /// Detect CPU information
    /// CPU情報検出
    fn detect_cpu_info() -> CpuInfo {
        let logical_cores = num_cpus::get();
        let physical_cores = num_cpus::get_physical();

        CpuInfo {
            vendor: Self::get_cpu_vendor(),
            model: Self::get_cpu_model(),
            physical_cores,
            logical_cores,
            base_freq: Self::get_cpu_frequency(),
            turbo_freq: Self::get_turbo_frequency(),
            extensions: Self::detect_cpu_extensions(),
        }
    }

    /// Get CPU vendor
    /// CPUベンダー取得
    fn get_cpu_vendor() -> String {
        #[cfg(target_arch = "x86_64")]
        return "x86_64".to_string();

        #[cfg(target_arch = "aarch64")]
        return "ARM".to_string();

        #[cfg(not(any(target_arch = "x86_64", target_arch = "aarch64")))]
        "Unknown".to_string()
    }

    /// Get CPU model
    /// CPUモデル取得
    fn get_cpu_model() -> String {
        #[cfg(target_arch = "x86_64")]
        return "x86_64 CPU".to_string();

        #[cfg(target_arch = "aarch64")]
        return "ARM CPU".to_string();

        #[cfg(not(any(target_arch = "x86_64", target_arch = "aarch64")))]
        "Unknown CPU".to_string()
    }

    /// Get CPU frequency
    /// CPU周波数取得
    fn get_cpu_frequency() -> usize {
        // Default: 2.0 GHz
        2000
    }

    /// Get turbo frequency
    /// ターボ周波数取得
    fn get_turbo_frequency() -> Option<usize> {
        None
    }

    /// Detect CPU extensions
    /// CPU拡張機能検出
    fn detect_cpu_extensions() -> Vec<String> {
        #[allow(unused_mut)]
        let mut extensions = Vec::new();

        #[cfg(target_arch = "x86_64")]
        {
            if is_x86_feature_detected!("sse") {
                extensions.push("SSE".to_string());
            }
            if is_x86_feature_detected!("sse2") {
                extensions.push("SSE2".to_string());
            }
            if is_x86_feature_detected!("sse3") {
                extensions.push("SSE3".to_string());
            }
            if is_x86_feature_detected!("ssse3") {
                extensions.push("SSSE3".to_string());
            }
            if is_x86_feature_detected!("sse4.1") {
                extensions.push("SSE4.1".to_string());
            }
            if is_x86_feature_detected!("sse4.2") {
                extensions.push("SSE4.2".to_string());
            }
            if is_x86_feature_detected!("avx") {
                extensions.push("AVX".to_string());
            }
            if is_x86_feature_detected!("avx2") {
                extensions.push("AVX2".to_string());
            }
            if is_x86_feature_detected!("avx512f") {
                extensions.push("AVX512F".to_string());
            }
            if is_x86_feature_detected!("fma") {
                extensions.push("FMA".to_string());
            }
        }

        #[cfg(target_arch = "aarch64")]
        {
            extensions.push("NEON".to_string());
            // Additional ARM extensions could be detected here
        }

        extensions
    }

    /// Detect available accelerators
    /// 利用可能アクセラレータ検出
    fn detect_accelerators() -> Vec<AcceleratorInfo> {
        #[allow(unused_mut)]
        let mut accelerators = Vec::new();

        // Check for CUDA devices
        #[cfg(feature = "cuda")]
        {
            if let Ok(cuda_devices) = Self::detect_cuda_devices() {
                accelerators.extend(cuda_devices);
            }
        }

        // Check for Metal devices (macOS)
        #[cfg(target_os = "macos")]
        {
            if let Ok(metal_devices) = Self::detect_metal_devices() {
                accelerators.extend(metal_devices);
            }
        }

        accelerators
    }

    /// Detect CUDA devices
    /// CUDAデバイス検出
    #[cfg(feature = "cuda")]
    fn detect_cuda_devices() -> RusTorchResult<Vec<AcceleratorInfo>> {
        // This would interface with CUDA runtime API
        // For now, return empty vector
        Ok(Vec::new())
    }

    #[cfg(not(feature = "cuda"))]
    fn detect_cuda_devices() -> RusTorchResult<Vec<AcceleratorInfo>> {
        Ok(Vec::new())
    }

    /// Detect Metal devices
    /// Metalデバイス検出
    #[cfg(target_os = "macos")]
    fn detect_metal_devices() -> RusTorchResult<Vec<AcceleratorInfo>> {
        // This would interface with Metal API
        // For now, create a placeholder for Apple Silicon GPU
        Ok(vec![AcceleratorInfo {
            accel_type: AcceleratorType::Metal,
            name: "Apple Silicon GPU".to_string(),
            compute_units: 8,                    // Placeholder
            clock_freq: 1300,                    // Placeholder
            memory_size: 8 * 1024 * 1024 * 1024, // 8GB shared
            memory_bandwidth: 200.0,             // GB/s placeholder
            compute_capability: 2.6,             // TFLOPS placeholder
            device_id: 0,
        }])
    }

    #[cfg(not(target_os = "macos"))]
    fn detect_metal_devices() -> RusTorchResult<Vec<AcceleratorInfo>> {
        Ok(Vec::new())
    }

    /// Detect memory hierarchy
    /// メモリ階層検出
    fn detect_memory_hierarchy() -> MemoryHierarchy {
        let mut latencies = HashMap::new();
        latencies.insert("L1".to_string(), 4);
        latencies.insert("L2".to_string(), 12);
        latencies.insert("L3".to_string(), 40);
        latencies.insert("Main".to_string(), 100);

        MemoryHierarchy {
            l1_cache: 32 * 1024,             // 32KB typical
            l2_cache: 256 * 1024,            // 256KB typical
            l3_cache: Some(8 * 1024 * 1024), // 8MB typical
            main_memory: Self::get_system_memory(),
            latencies,
        }
    }

    /// Get system memory
    /// システムメモリ取得
    fn get_system_memory() -> usize {
        #[cfg(target_os = "linux")]
        {
            // Linux memory detection would require sys-info crate
            8_usize
                .saturating_mul(1024)
                .saturating_mul(1024)
                .saturating_mul(1024)
        }
        #[cfg(not(target_os = "linux"))]
        {
            // Default: 8GB
            8_usize
                .saturating_mul(1024)
                .saturating_mul(1024)
                .saturating_mul(1024)
        }
    }

    /// Measure interconnect bandwidth
    /// インターコネクト帯域幅測定
    fn measure_interconnect_bandwidth() -> f64 {
        // This would perform actual bandwidth measurements
        // For now, return a typical value
        100.0 // GB/s
    }

    /// Detect power constraints
    /// 電力制約検出
    fn detect_power_constraints() -> Option<f64> {
        // This would interface with power management APIs
        None
    }

    /// Select best accelerator
    /// 最適アクセラレータ選択
    fn select_best_accelerator(capabilities: &HardwareCapabilities) -> Option<AcceleratorInfo> {
        capabilities
            .accelerators
            .iter()
            .max_by(|a, b| {
                a.compute_capability
                    .partial_cmp(&b.compute_capability)
                    .unwrap_or(std::cmp::Ordering::Equal)
            })
            .cloned()
    }

    /// Get optimal data layout for hardware
    /// ハードウェアに最適なデータレイアウト取得
    pub fn optimal_data_layout(&self, tensor_shape: &[usize]) -> DataLayout {
        if let Some(accel) = &self.selected_accelerator {
            match accel.accel_type {
                AcceleratorType::CUDA | AcceleratorType::ROCm => {
                    // GPUs prefer coalesced memory access
                    DataLayout::RowMajor
                }
                AcceleratorType::Metal => {
                    // Metal prefers specific layouts for textures
                    DataLayout::Tiled
                }
                _ => DataLayout::RowMajor,
            }
        } else {
            // CPU: consider cache lines
            if tensor_shape.len() == 2 && tensor_shape[1] % 8 == 0 {
                DataLayout::RowMajor
            } else {
                DataLayout::ColumnMajor
            }
        }
    }

    /// Calculate optimal tile size for operations
    /// 演算の最適タイルサイズ計算
    pub fn optimal_tile_size(&self, operation: &str) -> (usize, usize) {
        let cache_size = self.capabilities.memory_hierarchy.l1_cache;
        let element_size = std::mem::size_of::<f32>();

        match operation {
            "matmul" => {
                // Optimize for L1 cache
                let tile_elements = cache_size / (3 * element_size); // 3 matrices
                let tile_dim = (tile_elements as f64).sqrt() as usize;
                (tile_dim, tile_dim)
            }
            "conv2d" => {
                // Different tiling for convolution
                (32, 32)
            }
            _ => (64, 64),
        }
    }

    /// Get hardware capabilities
    /// ハードウェア機能取得
    pub fn capabilities(&self) -> &HardwareCapabilities {
        &self.capabilities
    }

    /// Get selected accelerator
    /// 選択済みアクセラレータ取得
    pub fn selected_accelerator(&self) -> Option<&AcceleratorInfo> {
        self.selected_accelerator.as_ref()
    }
}

/// Data layout preferences
/// データレイアウト設定
#[derive(Debug, Clone, Copy)]
pub enum DataLayout {
    /// Row-major (C-style)
    RowMajor,
    /// Column-major (Fortran-style)
    ColumnMajor,
    /// Tiled layout
    Tiled,
    /// Custom layout
    Custom,
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn test_hardware_detection() {
        let optimizer = HardwareOptimizer::new();
        let capabilities = optimizer.capabilities();

        println!("CPU Information:");
        println!("  Vendor: {}", capabilities.cpu_info.vendor);
        println!("  Model: {}", capabilities.cpu_info.model);
        println!("  Physical cores: {}", capabilities.cpu_info.physical_cores);
        println!("  Logical cores: {}", capabilities.cpu_info.logical_cores);
        println!("  Base frequency: {} MHz", capabilities.cpu_info.base_freq);
        println!("  Extensions: {:?}", capabilities.cpu_info.extensions);

        println!("\nMemory Hierarchy:");
        println!(
            "  L1 cache: {} KB",
            capabilities.memory_hierarchy.l1_cache / 1024
        );
        println!(
            "  L2 cache: {} KB",
            capabilities.memory_hierarchy.l2_cache / 1024
        );
        if let Some(l3) = capabilities.memory_hierarchy.l3_cache {
            println!("  L3 cache: {} MB", l3 / (1024 * 1024));
        }

        println!(
            "\nAccelerators: {} detected",
            capabilities.accelerators.len()
        );
        for accel in &capabilities.accelerators {
            println!("  - {} ({})", accel.name, accel.compute_capability);
        }

        assert!(capabilities.cpu_info.logical_cores > 0);
    }

    #[test]
    fn test_optimal_layouts() {
        let optimizer = HardwareOptimizer::new();

        let layout1 = optimizer.optimal_data_layout(&[1024, 1024]);
        let layout2 = optimizer.optimal_data_layout(&[100, 7]);

        println!("Optimal layout for [1024, 1024]: {:?}", layout1);
        println!("Optimal layout for [100, 7]: {:?}", layout2);
    }

    #[test]
    fn test_tile_size_calculation() {
        let optimizer = HardwareOptimizer::new();

        let (m, n) = optimizer.optimal_tile_size("matmul");
        println!("Optimal tile size for matmul: {}x{}", m, n);

        assert!(m > 0 && n > 0);
    }
}