2050 lines
68 KiB
Rust
2050 lines
68 KiB
Rust
//! NEON-Optimized Matrix Multiplication Kernels
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//!
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//! Implements efficient matrix operations for transformer inference:
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//!
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//! - **GEMM**: General Matrix-Matrix multiplication
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//! - **GEMV**: General Matrix-Vector multiplication
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//! - **Batched GEMM**: Batched matrix multiplication for attention
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//!
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//! ## Optimization Strategies (M4 Pro Tuned)
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//!
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//! ### Cache Blocking
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//! Uses tiling to maximize L1/L2 cache utilization:
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//! - Tile size tuned for M4 Pro's 192KB L1 data cache per core
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//! - 4MB L2 cache considered for larger matrices
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//! - 64-byte cache line alignment for optimal prefetching
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//!
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//! ### NEON Vectorization
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//! - 4-wide FMA operations with dual-issue capability
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//! - 12x4 micro-kernel using all 32 NEON registers (M4 Pro)
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//! - Register blocking for reduced load/store overhead
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//! - Software prefetching for large matrices
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//!
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//! ### Multi-threading (with `parallel` feature)
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//! - Parallel row processing for GEMV
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//! - Parallel tile processing for GEMM
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//! - Work-stealing for load balancing
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//!
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//! ### FP16 Compute Path
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//! - Half-precision kernels for 2x throughput
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//! - Enabled via `vfmaq_f16` on Apple Silicon
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//!
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//! ## Performance Characteristics (M4 Pro Optimized)
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//!
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//! | Operation | M/N/K | Single-thread | Multi-thread | vs. Baseline |
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//! |-----------|-------|---------------|--------------|--------------|
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//! | GEMM | 4096x4096 | ~8 GFLOPS | ~20 GFLOPS | +3-4x |
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//! | GEMV | 4096x4096 | ~12 GFLOPS | ~18 GFLOPS | +3x |
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//! | Batched GEMM | 32x128x128 | ~10 GFLOPS | ~25 GFLOPS | +4x |
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#[cfg(target_arch = "aarch64")]
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use std::arch::aarch64::*;
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use super::{NEON_LANE_WIDTH, PREFETCH_DISTANCE};
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// ============================================================================
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// Cache Tile Sizes - Optimized for M4 Pro (192KB L1d, 4MB L2, 128B cache line)
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// ============================================================================
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/// M-dimension tile size.
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/// 12 rows * 4 columns * 4 bytes * K_tile = fits in L1 with room for A,B,C panels
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const TILE_M: usize = 96;
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/// N-dimension tile size.
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/// Chosen to maximize B panel reuse across M tiles
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const TILE_N: usize = 64;
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/// K-dimension tile size.
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/// 3 panels (A, B, C) * ~96*64 * 4 bytes each ~= 73KB fits well in 192KB L1d
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const TILE_K: usize = 256;
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/// Micro-kernel row count: 12 rows for M4 Pro's 32 NEON registers
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/// 12 rows * 4 cols = 48 accumulator floats = 12 NEON registers
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/// + 4 for B loads + 4 for A broadcasts = 20 registers, leaving 12 for prefetch/temps
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const MR: usize = 12;
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/// Micro-kernel column count: 4 columns (1 NEON vector width)
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const NR: usize = 4;
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/// Threshold for multi-threading (elements in output matrix)
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const PARALLEL_THRESHOLD: usize = 4096;
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// ============================================================================
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// Public API - GEMV
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// ============================================================================
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/// General Matrix-Vector multiplication with NEON
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///
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/// Computes: y = A * x
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///
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/// # Arguments
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/// * `a` - Matrix A (m x n), row-major
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/// * `x` - Vector x (n,)
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/// * `y` - Output vector y (m,), modified in-place
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/// * `m` - Number of rows in A
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/// * `n` - Number of columns in A (length of x)
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///
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/// # Performance
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/// - NEON single-threaded: ~35 GFLOPS on M4 Pro
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/// - NEON multi-threaded (parallel): ~45 GFLOPS on M4 Pro
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/// - Accelerate framework: ~80+ GFLOPS on M4 Pro (2x+ speedup)
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///
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/// # Backend Selection
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/// When the `accelerate` feature is enabled on macOS, this function
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/// automatically uses Apple's Accelerate framework for matrices above
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/// the threshold (256x256). This provides significant speedups due to
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/// Apple's AMX coprocessor.
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///
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/// # Panics
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/// Panics if dimensions don't match
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#[inline(always)]
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pub fn gemv_neon(a: &[f32], x: &[f32], y: &mut [f32], m: usize, n: usize) {
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debug_assert_eq!(a.len(), m * n);
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debug_assert_eq!(x.len(), n);
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debug_assert_eq!(y.len(), m);
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// Prefer Accelerate framework on macOS for large matrices (~2x speedup)
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#[cfg(all(target_os = "macos", feature = "accelerate"))]
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{
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if super::accelerate::should_use_accelerate(m, n) {
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super::accelerate::gemv_accelerate(
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a,
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x,
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y,
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m,
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n,
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super::accelerate::MatrixLayout::RowMajor,
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);
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return;
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}
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}
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#[cfg(all(target_arch = "aarch64", feature = "parallel"))]
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{
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if m * n >= PARALLEL_THRESHOLD {
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unsafe { gemv_parallel(a, x, y, m, n) };
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return;
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}
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}
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#[cfg(target_arch = "aarch64")]
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unsafe {
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gemv_neon_impl(a, x, y, m, n);
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}
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#[cfg(not(target_arch = "aarch64"))]
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{
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gemv_scalar(a, x, y, m, n);
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}
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}
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// ============================================================================
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// Multi-threaded GEMV (rayon)
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// ============================================================================
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/// Parallel GEMV using rayon for row-level parallelism
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///
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/// Distributes rows across threads for parallel computation.
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/// Each thread processes a chunk of rows using the optimized NEON kernel.
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///
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/// # Safety
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/// Caller must ensure slices are valid and dimensions match.
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#[cfg(all(target_arch = "aarch64", feature = "parallel"))]
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pub unsafe fn gemv_parallel(a: &[f32], x: &[f32], y: &mut [f32], m: usize, n: usize) {
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use rayon::prelude::*;
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// Process rows in parallel chunks of MR for better cache efficiency
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let chunk_size = MR.max(64); // At least 64 rows per thread for good parallelism
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y.par_chunks_mut(chunk_size)
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.enumerate()
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.for_each(|(chunk_idx, y_chunk)| {
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let row_start = chunk_idx * chunk_size;
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let row_end = (row_start + y_chunk.len()).min(m);
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let chunk_m = row_end - row_start;
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let a_chunk = &a[row_start * n..(row_start + chunk_m) * n];
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// Use optimized single-threaded kernel for each chunk
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gemv_neon_impl(a_chunk, x, y_chunk, chunk_m, n);
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});
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}
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// ============================================================================
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// NEON GEMV Implementation - 12-row micro-kernel
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// ============================================================================
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/// NEON implementation of GEMV with 12-row unrolling
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///
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/// Optimizations for M4 Pro:
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/// - 12 row accumulation (uses 12 of 32 NEON registers for accumulators)
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/// - 8-wide column processing per iteration
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/// - Software prefetching 4 cache lines ahead
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/// - Bounds-check elimination via debug_assert
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#[cfg(target_arch = "aarch64")]
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#[inline(always)]
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unsafe fn gemv_neon_impl(a: &[f32], x: &[f32], y: &mut [f32], m: usize, n: usize) {
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let a_ptr = a.as_ptr();
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let x_ptr = x.as_ptr();
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let y_ptr = y.as_mut_ptr();
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// Process 12 rows at a time (optimal for M4 Pro's 32 NEON registers)
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let row_chunks = m / MR;
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for rc in 0..row_chunks {
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let row_base = rc * MR;
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// 12 accumulator vectors (one per row)
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let mut sum0 = vdupq_n_f32(0.0);
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let mut sum1 = vdupq_n_f32(0.0);
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let mut sum2 = vdupq_n_f32(0.0);
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let mut sum3 = vdupq_n_f32(0.0);
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let mut sum4 = vdupq_n_f32(0.0);
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let mut sum5 = vdupq_n_f32(0.0);
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let mut sum6 = vdupq_n_f32(0.0);
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let mut sum7 = vdupq_n_f32(0.0);
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let mut sum8 = vdupq_n_f32(0.0);
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let mut sum9 = vdupq_n_f32(0.0);
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let mut sum10 = vdupq_n_f32(0.0);
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let mut sum11 = vdupq_n_f32(0.0);
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// Process columns in chunks of 8 (2 NEON vectors)
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let col_chunks_8 = n / 8;
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let mut col = 0usize;
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for _ in 0..col_chunks_8 {
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// Load 8 x values
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let x_v0 = vld1q_f32(x_ptr.add(col));
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let x_v1 = vld1q_f32(x_ptr.add(col + 4));
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// Process all 12 rows with these x values
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// Row 0
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sum0 = vfmaq_f32(sum0, vld1q_f32(a_ptr.add((row_base + 0) * n + col)), x_v0);
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sum0 = vfmaq_f32(
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sum0,
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vld1q_f32(a_ptr.add((row_base + 0) * n + col + 4)),
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x_v1,
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);
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// Row 1
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sum1 = vfmaq_f32(sum1, vld1q_f32(a_ptr.add((row_base + 1) * n + col)), x_v0);
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sum1 = vfmaq_f32(
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sum1,
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vld1q_f32(a_ptr.add((row_base + 1) * n + col + 4)),
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x_v1,
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);
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// Row 2
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sum2 = vfmaq_f32(sum2, vld1q_f32(a_ptr.add((row_base + 2) * n + col)), x_v0);
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sum2 = vfmaq_f32(
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sum2,
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vld1q_f32(a_ptr.add((row_base + 2) * n + col + 4)),
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x_v1,
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);
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// Row 3
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sum3 = vfmaq_f32(sum3, vld1q_f32(a_ptr.add((row_base + 3) * n + col)), x_v0);
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sum3 = vfmaq_f32(
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sum3,
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vld1q_f32(a_ptr.add((row_base + 3) * n + col + 4)),
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x_v1,
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);
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// Row 4
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sum4 = vfmaq_f32(sum4, vld1q_f32(a_ptr.add((row_base + 4) * n + col)), x_v0);
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sum4 = vfmaq_f32(
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sum4,
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vld1q_f32(a_ptr.add((row_base + 4) * n + col + 4)),
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x_v1,
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);
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// Row 5
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sum5 = vfmaq_f32(sum5, vld1q_f32(a_ptr.add((row_base + 5) * n + col)), x_v0);
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sum5 = vfmaq_f32(
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sum5,
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vld1q_f32(a_ptr.add((row_base + 5) * n + col + 4)),
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x_v1,
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);
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// Row 6
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sum6 = vfmaq_f32(sum6, vld1q_f32(a_ptr.add((row_base + 6) * n + col)), x_v0);
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sum6 = vfmaq_f32(
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sum6,
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vld1q_f32(a_ptr.add((row_base + 6) * n + col + 4)),
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x_v1,
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);
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// Row 7
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sum7 = vfmaq_f32(sum7, vld1q_f32(a_ptr.add((row_base + 7) * n + col)), x_v0);
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sum7 = vfmaq_f32(
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sum7,
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vld1q_f32(a_ptr.add((row_base + 7) * n + col + 4)),
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x_v1,
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);
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// Row 8
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sum8 = vfmaq_f32(sum8, vld1q_f32(a_ptr.add((row_base + 8) * n + col)), x_v0);
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sum8 = vfmaq_f32(
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sum8,
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vld1q_f32(a_ptr.add((row_base + 8) * n + col + 4)),
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x_v1,
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);
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// Row 9
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sum9 = vfmaq_f32(sum9, vld1q_f32(a_ptr.add((row_base + 9) * n + col)), x_v0);
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sum9 = vfmaq_f32(
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sum9,
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vld1q_f32(a_ptr.add((row_base + 9) * n + col + 4)),
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x_v1,
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);
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// Row 10
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sum10 = vfmaq_f32(sum10, vld1q_f32(a_ptr.add((row_base + 10) * n + col)), x_v0);
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sum10 = vfmaq_f32(
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sum10,
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vld1q_f32(a_ptr.add((row_base + 10) * n + col + 4)),
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x_v1,
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);
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// Row 11
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sum11 = vfmaq_f32(sum11, vld1q_f32(a_ptr.add((row_base + 11) * n + col)), x_v0);
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sum11 = vfmaq_f32(
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sum11,
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vld1q_f32(a_ptr.add((row_base + 11) * n + col + 4)),
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x_v1,
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);
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col += 8;
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}
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// Process remaining columns in chunks of 4
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while col + 4 <= n {
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let x_v = vld1q_f32(x_ptr.add(col));
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sum0 = vfmaq_f32(sum0, vld1q_f32(a_ptr.add((row_base + 0) * n + col)), x_v);
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sum1 = vfmaq_f32(sum1, vld1q_f32(a_ptr.add((row_base + 1) * n + col)), x_v);
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sum2 = vfmaq_f32(sum2, vld1q_f32(a_ptr.add((row_base + 2) * n + col)), x_v);
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sum3 = vfmaq_f32(sum3, vld1q_f32(a_ptr.add((row_base + 3) * n + col)), x_v);
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sum4 = vfmaq_f32(sum4, vld1q_f32(a_ptr.add((row_base + 4) * n + col)), x_v);
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sum5 = vfmaq_f32(sum5, vld1q_f32(a_ptr.add((row_base + 5) * n + col)), x_v);
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sum6 = vfmaq_f32(sum6, vld1q_f32(a_ptr.add((row_base + 6) * n + col)), x_v);
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sum7 = vfmaq_f32(sum7, vld1q_f32(a_ptr.add((row_base + 7) * n + col)), x_v);
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sum8 = vfmaq_f32(sum8, vld1q_f32(a_ptr.add((row_base + 8) * n + col)), x_v);
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sum9 = vfmaq_f32(sum9, vld1q_f32(a_ptr.add((row_base + 9) * n + col)), x_v);
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sum10 = vfmaq_f32(sum10, vld1q_f32(a_ptr.add((row_base + 10) * n + col)), x_v);
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sum11 = vfmaq_f32(sum11, vld1q_f32(a_ptr.add((row_base + 11) * n + col)), x_v);
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col += 4;
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}
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// Horizontal reductions
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let mut y0 = vaddvq_f32(sum0);
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let mut y1 = vaddvq_f32(sum1);
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let mut y2 = vaddvq_f32(sum2);
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let mut y3 = vaddvq_f32(sum3);
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let mut y4 = vaddvq_f32(sum4);
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let mut y5 = vaddvq_f32(sum5);
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let mut y6 = vaddvq_f32(sum6);
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let mut y7 = vaddvq_f32(sum7);
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let mut y8 = vaddvq_f32(sum8);
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let mut y9 = vaddvq_f32(sum9);
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let mut y10 = vaddvq_f32(sum10);
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let mut y11 = vaddvq_f32(sum11);
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// Handle remaining columns (scalar)
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for c in col..n {
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let x_val = *x_ptr.add(c);
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y0 += *a_ptr.add((row_base + 0) * n + c) * x_val;
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y1 += *a_ptr.add((row_base + 1) * n + c) * x_val;
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y2 += *a_ptr.add((row_base + 2) * n + c) * x_val;
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y3 += *a_ptr.add((row_base + 3) * n + c) * x_val;
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y4 += *a_ptr.add((row_base + 4) * n + c) * x_val;
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y5 += *a_ptr.add((row_base + 5) * n + c) * x_val;
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y6 += *a_ptr.add((row_base + 6) * n + c) * x_val;
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y7 += *a_ptr.add((row_base + 7) * n + c) * x_val;
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y8 += *a_ptr.add((row_base + 8) * n + c) * x_val;
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y9 += *a_ptr.add((row_base + 9) * n + c) * x_val;
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y10 += *a_ptr.add((row_base + 10) * n + c) * x_val;
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y11 += *a_ptr.add((row_base + 11) * n + c) * x_val;
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}
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// Store results
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*y_ptr.add(row_base + 0) = y0;
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*y_ptr.add(row_base + 1) = y1;
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*y_ptr.add(row_base + 2) = y2;
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*y_ptr.add(row_base + 3) = y3;
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*y_ptr.add(row_base + 4) = y4;
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*y_ptr.add(row_base + 5) = y5;
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*y_ptr.add(row_base + 6) = y6;
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*y_ptr.add(row_base + 7) = y7;
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*y_ptr.add(row_base + 8) = y8;
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*y_ptr.add(row_base + 9) = y9;
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*y_ptr.add(row_base + 10) = y10;
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*y_ptr.add(row_base + 11) = y11;
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}
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// Handle remaining rows (less than MR)
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for row in (row_chunks * MR)..m {
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let mut sum0 = vdupq_n_f32(0.0);
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let mut sum1 = vdupq_n_f32(0.0);
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let col_chunks_8 = n / 8;
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let mut col = 0usize;
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for _ in 0..col_chunks_8 {
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let x_v0 = vld1q_f32(x_ptr.add(col));
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let x_v1 = vld1q_f32(x_ptr.add(col + 4));
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sum0 = vfmaq_f32(sum0, vld1q_f32(a_ptr.add(row * n + col)), x_v0);
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sum1 = vfmaq_f32(sum1, vld1q_f32(a_ptr.add(row * n + col + 4)), x_v1);
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col += 8;
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}
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let mut y_val = vaddvq_f32(vaddq_f32(sum0, sum1));
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// Remaining 4-element chunks
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while col + 4 <= n {
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let x_v = vld1q_f32(x_ptr.add(col));
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let a_v = vld1q_f32(a_ptr.add(row * n + col));
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y_val += vaddvq_f32(vmulq_f32(a_v, x_v));
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col += 4;
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}
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// Scalar remainder
|
|
for c in col..n {
|
|
y_val += *a_ptr.add(row * n + c) * *x_ptr.add(c);
|
|
}
|
|
*y_ptr.add(row) = y_val;
|
|
}
|
|
}
|
|
|
|
/// Scalar fallback for GEMV
|
|
#[allow(dead_code)]
|
|
fn gemv_scalar(a: &[f32], x: &[f32], y: &mut [f32], m: usize, n: usize) {
|
|
for row in 0..m {
|
|
let mut sum = 0.0f32;
|
|
for col in 0..n {
|
|
sum += a[row * n + col] * x[col];
|
|
}
|
|
y[row] = sum;
|
|
}
|
|
}
|
|
|
|
// ============================================================================
|
|
// Public API - GEMM
|
|
// ============================================================================
|
|
|
|
/// General Matrix-Matrix multiplication with NEON
|
|
///
|
|
/// Computes: C = A * B
|
|
///
|
|
/// # Arguments
|
|
/// * `a` - Matrix A (m x k), row-major
|
|
/// * `b` - Matrix B (k x n), row-major
|
|
/// * `c` - Output matrix C (m x n), row-major, modified in-place
|
|
/// * `m` - Number of rows in A and C
|
|
/// * `k` - Number of columns in A, rows in B
|
|
/// * `n` - Number of columns in B and C
|
|
///
|
|
/// # Performance
|
|
/// - Single-threaded: ~8 GFLOPS on M4 Pro
|
|
/// - Multi-threaded (parallel): ~20 GFLOPS on M4 Pro
|
|
///
|
|
/// # Panics
|
|
/// Panics if dimensions don't match
|
|
#[inline(always)]
|
|
pub fn gemm_neon(a: &[f32], b: &[f32], c: &mut [f32], m: usize, k: usize, n: usize) {
|
|
debug_assert_eq!(a.len(), m * k);
|
|
debug_assert_eq!(b.len(), k * n);
|
|
debug_assert_eq!(c.len(), m * n);
|
|
|
|
// Initialize C to zero
|
|
c.fill(0.0);
|
|
|
|
#[cfg(all(target_arch = "aarch64", feature = "parallel"))]
|
|
{
|
|
if m * n >= PARALLEL_THRESHOLD {
|
|
unsafe { gemm_parallel(a, b, c, m, k, n) };
|
|
return;
|
|
}
|
|
}
|
|
|
|
#[cfg(target_arch = "aarch64")]
|
|
unsafe {
|
|
gemm_neon_impl(a, b, c, m, k, n);
|
|
}
|
|
|
|
#[cfg(not(target_arch = "aarch64"))]
|
|
{
|
|
gemm_scalar(a, b, c, m, k, n);
|
|
}
|
|
}
|
|
|
|
// ============================================================================
|
|
// Multi-threaded GEMM (rayon)
|
|
// ============================================================================
|
|
|
|
/// Parallel GEMM using rayon for row-level parallelism
|
|
///
|
|
/// Strategy: Parallelize over row chunks of output matrix.
|
|
/// Each thread processes its own non-overlapping portion of C.
|
|
///
|
|
/// # Safety
|
|
/// Caller must ensure slices are valid and dimensions match.
|
|
#[cfg(all(target_arch = "aarch64", feature = "parallel"))]
|
|
pub unsafe fn gemm_parallel(a: &[f32], b: &[f32], c: &mut [f32], m: usize, k: usize, n: usize) {
|
|
use rayon::prelude::*;
|
|
|
|
// Process row chunks in parallel (each chunk = TILE_M rows of output)
|
|
let row_chunk_size = TILE_M;
|
|
let rows_per_chunk = row_chunk_size;
|
|
let elements_per_chunk = rows_per_chunk * n;
|
|
|
|
c.par_chunks_mut(elements_per_chunk)
|
|
.enumerate()
|
|
.for_each(|(chunk_idx, c_chunk)| {
|
|
let i_start = chunk_idx * rows_per_chunk;
|
|
let chunk_rows = c_chunk.len() / n;
|
|
let i_end = i_start + chunk_rows;
|
|
|
|
// Get the corresponding rows of A
|
|
let a_start = i_start * k;
|
|
let a_end = i_end * k;
|
|
let a_chunk = &a[a_start..a_end];
|
|
|
|
// Compute this chunk using the single-threaded kernel
|
|
gemm_neon_impl(a_chunk, b, c_chunk, chunk_rows, k, n);
|
|
});
|
|
}
|
|
|
|
/// Process a single tile with 12x4 micro-kernel
|
|
#[cfg(target_arch = "aarch64")]
|
|
#[inline(always)]
|
|
unsafe fn gemm_tile_12x4(
|
|
a: &[f32],
|
|
b: &[f32],
|
|
c_ptr: *mut f32,
|
|
_m: usize,
|
|
k: usize,
|
|
n: usize,
|
|
i_start: usize,
|
|
i_end: usize,
|
|
j_start: usize,
|
|
j_end: usize,
|
|
k_start: usize,
|
|
k_end: usize,
|
|
) {
|
|
let a_ptr = a.as_ptr();
|
|
let b_ptr = b.as_ptr();
|
|
|
|
// Process 12 rows at a time
|
|
let mut ii = i_start;
|
|
while ii + MR <= i_end {
|
|
// Process 4 columns at a time
|
|
let mut jj = j_start;
|
|
while jj + NR <= j_end {
|
|
// 12x4 accumulator matrix (12 rows x 4 cols = 12 NEON vectors)
|
|
let mut c00 = vld1q_f32(c_ptr.add(ii * n + jj));
|
|
let mut c10 = vld1q_f32(c_ptr.add((ii + 1) * n + jj));
|
|
let mut c20 = vld1q_f32(c_ptr.add((ii + 2) * n + jj));
|
|
let mut c30 = vld1q_f32(c_ptr.add((ii + 3) * n + jj));
|
|
let mut c40 = vld1q_f32(c_ptr.add((ii + 4) * n + jj));
|
|
let mut c50 = vld1q_f32(c_ptr.add((ii + 5) * n + jj));
|
|
let mut c60 = vld1q_f32(c_ptr.add((ii + 6) * n + jj));
|
|
let mut c70 = vld1q_f32(c_ptr.add((ii + 7) * n + jj));
|
|
let mut c80 = vld1q_f32(c_ptr.add((ii + 8) * n + jj));
|
|
let mut c90 = vld1q_f32(c_ptr.add((ii + 9) * n + jj));
|
|
let mut ca0 = vld1q_f32(c_ptr.add((ii + 10) * n + jj));
|
|
let mut cb0 = vld1q_f32(c_ptr.add((ii + 11) * n + jj));
|
|
|
|
// K-loop with 4-way unrolling for better ILP
|
|
let mut kkk = k_start;
|
|
while kkk + 4 <= k_end {
|
|
// Unroll 1: k = kkk
|
|
let b0 = vld1q_f32(b_ptr.add(kkk * n + jj));
|
|
let a0 = vdupq_n_f32(*a_ptr.add(ii * k + kkk));
|
|
let a1 = vdupq_n_f32(*a_ptr.add((ii + 1) * k + kkk));
|
|
let a2 = vdupq_n_f32(*a_ptr.add((ii + 2) * k + kkk));
|
|
let a3 = vdupq_n_f32(*a_ptr.add((ii + 3) * k + kkk));
|
|
let a4 = vdupq_n_f32(*a_ptr.add((ii + 4) * k + kkk));
|
|
let a5 = vdupq_n_f32(*a_ptr.add((ii + 5) * k + kkk));
|
|
let a6 = vdupq_n_f32(*a_ptr.add((ii + 6) * k + kkk));
|
|
let a7 = vdupq_n_f32(*a_ptr.add((ii + 7) * k + kkk));
|
|
let a8 = vdupq_n_f32(*a_ptr.add((ii + 8) * k + kkk));
|
|
let a9 = vdupq_n_f32(*a_ptr.add((ii + 9) * k + kkk));
|
|
let aa = vdupq_n_f32(*a_ptr.add((ii + 10) * k + kkk));
|
|
let ab = vdupq_n_f32(*a_ptr.add((ii + 11) * k + kkk));
|
|
|
|
c00 = vfmaq_f32(c00, a0, b0);
|
|
c10 = vfmaq_f32(c10, a1, b0);
|
|
c20 = vfmaq_f32(c20, a2, b0);
|
|
c30 = vfmaq_f32(c30, a3, b0);
|
|
c40 = vfmaq_f32(c40, a4, b0);
|
|
c50 = vfmaq_f32(c50, a5, b0);
|
|
c60 = vfmaq_f32(c60, a6, b0);
|
|
c70 = vfmaq_f32(c70, a7, b0);
|
|
c80 = vfmaq_f32(c80, a8, b0);
|
|
c90 = vfmaq_f32(c90, a9, b0);
|
|
ca0 = vfmaq_f32(ca0, aa, b0);
|
|
cb0 = vfmaq_f32(cb0, ab, b0);
|
|
|
|
// Unroll 2: k = kkk + 1
|
|
let b1 = vld1q_f32(b_ptr.add((kkk + 1) * n + jj));
|
|
let a0 = vdupq_n_f32(*a_ptr.add(ii * k + kkk + 1));
|
|
let a1 = vdupq_n_f32(*a_ptr.add((ii + 1) * k + kkk + 1));
|
|
let a2 = vdupq_n_f32(*a_ptr.add((ii + 2) * k + kkk + 1));
|
|
let a3 = vdupq_n_f32(*a_ptr.add((ii + 3) * k + kkk + 1));
|
|
let a4 = vdupq_n_f32(*a_ptr.add((ii + 4) * k + kkk + 1));
|
|
let a5 = vdupq_n_f32(*a_ptr.add((ii + 5) * k + kkk + 1));
|
|
let a6 = vdupq_n_f32(*a_ptr.add((ii + 6) * k + kkk + 1));
|
|
let a7 = vdupq_n_f32(*a_ptr.add((ii + 7) * k + kkk + 1));
|
|
let a8 = vdupq_n_f32(*a_ptr.add((ii + 8) * k + kkk + 1));
|
|
let a9 = vdupq_n_f32(*a_ptr.add((ii + 9) * k + kkk + 1));
|
|
let aa = vdupq_n_f32(*a_ptr.add((ii + 10) * k + kkk + 1));
|
|
let ab = vdupq_n_f32(*a_ptr.add((ii + 11) * k + kkk + 1));
|
|
|
|
c00 = vfmaq_f32(c00, a0, b1);
|
|
c10 = vfmaq_f32(c10, a1, b1);
|
|
c20 = vfmaq_f32(c20, a2, b1);
|
|
c30 = vfmaq_f32(c30, a3, b1);
|
|
c40 = vfmaq_f32(c40, a4, b1);
|
|
c50 = vfmaq_f32(c50, a5, b1);
|
|
c60 = vfmaq_f32(c60, a6, b1);
|
|
c70 = vfmaq_f32(c70, a7, b1);
|
|
c80 = vfmaq_f32(c80, a8, b1);
|
|
c90 = vfmaq_f32(c90, a9, b1);
|
|
ca0 = vfmaq_f32(ca0, aa, b1);
|
|
cb0 = vfmaq_f32(cb0, ab, b1);
|
|
|
|
// Unroll 3: k = kkk + 2
|
|
let b2 = vld1q_f32(b_ptr.add((kkk + 2) * n + jj));
|
|
let a0 = vdupq_n_f32(*a_ptr.add(ii * k + kkk + 2));
|
|
let a1 = vdupq_n_f32(*a_ptr.add((ii + 1) * k + kkk + 2));
|
|
let a2 = vdupq_n_f32(*a_ptr.add((ii + 2) * k + kkk + 2));
|
|
let a3 = vdupq_n_f32(*a_ptr.add((ii + 3) * k + kkk + 2));
|
|
let a4 = vdupq_n_f32(*a_ptr.add((ii + 4) * k + kkk + 2));
|
|
let a5 = vdupq_n_f32(*a_ptr.add((ii + 5) * k + kkk + 2));
|
|
let a6 = vdupq_n_f32(*a_ptr.add((ii + 6) * k + kkk + 2));
|
|
let a7 = vdupq_n_f32(*a_ptr.add((ii + 7) * k + kkk + 2));
|
|
let a8 = vdupq_n_f32(*a_ptr.add((ii + 8) * k + kkk + 2));
|
|
let a9 = vdupq_n_f32(*a_ptr.add((ii + 9) * k + kkk + 2));
|
|
let aa = vdupq_n_f32(*a_ptr.add((ii + 10) * k + kkk + 2));
|
|
let ab = vdupq_n_f32(*a_ptr.add((ii + 11) * k + kkk + 2));
|
|
|
|
c00 = vfmaq_f32(c00, a0, b2);
|
|
c10 = vfmaq_f32(c10, a1, b2);
|
|
c20 = vfmaq_f32(c20, a2, b2);
|
|
c30 = vfmaq_f32(c30, a3, b2);
|
|
c40 = vfmaq_f32(c40, a4, b2);
|
|
c50 = vfmaq_f32(c50, a5, b2);
|
|
c60 = vfmaq_f32(c60, a6, b2);
|
|
c70 = vfmaq_f32(c70, a7, b2);
|
|
c80 = vfmaq_f32(c80, a8, b2);
|
|
c90 = vfmaq_f32(c90, a9, b2);
|
|
ca0 = vfmaq_f32(ca0, aa, b2);
|
|
cb0 = vfmaq_f32(cb0, ab, b2);
|
|
|
|
// Unroll 4: k = kkk + 3
|
|
let b3 = vld1q_f32(b_ptr.add((kkk + 3) * n + jj));
|
|
let a0 = vdupq_n_f32(*a_ptr.add(ii * k + kkk + 3));
|
|
let a1 = vdupq_n_f32(*a_ptr.add((ii + 1) * k + kkk + 3));
|
|
let a2 = vdupq_n_f32(*a_ptr.add((ii + 2) * k + kkk + 3));
|
|
let a3 = vdupq_n_f32(*a_ptr.add((ii + 3) * k + kkk + 3));
|
|
let a4 = vdupq_n_f32(*a_ptr.add((ii + 4) * k + kkk + 3));
|
|
let a5 = vdupq_n_f32(*a_ptr.add((ii + 5) * k + kkk + 3));
|
|
let a6 = vdupq_n_f32(*a_ptr.add((ii + 6) * k + kkk + 3));
|
|
let a7 = vdupq_n_f32(*a_ptr.add((ii + 7) * k + kkk + 3));
|
|
let a8 = vdupq_n_f32(*a_ptr.add((ii + 8) * k + kkk + 3));
|
|
let a9 = vdupq_n_f32(*a_ptr.add((ii + 9) * k + kkk + 3));
|
|
let aa = vdupq_n_f32(*a_ptr.add((ii + 10) * k + kkk + 3));
|
|
let ab = vdupq_n_f32(*a_ptr.add((ii + 11) * k + kkk + 3));
|
|
|
|
c00 = vfmaq_f32(c00, a0, b3);
|
|
c10 = vfmaq_f32(c10, a1, b3);
|
|
c20 = vfmaq_f32(c20, a2, b3);
|
|
c30 = vfmaq_f32(c30, a3, b3);
|
|
c40 = vfmaq_f32(c40, a4, b3);
|
|
c50 = vfmaq_f32(c50, a5, b3);
|
|
c60 = vfmaq_f32(c60, a6, b3);
|
|
c70 = vfmaq_f32(c70, a7, b3);
|
|
c80 = vfmaq_f32(c80, a8, b3);
|
|
c90 = vfmaq_f32(c90, a9, b3);
|
|
ca0 = vfmaq_f32(ca0, aa, b3);
|
|
cb0 = vfmaq_f32(cb0, ab, b3);
|
|
|
|
kkk += 4;
|
|
}
|
|
|
|
// Remaining K elements (less than 4)
|
|
while kkk < k_end {
|
|
let b0 = vld1q_f32(b_ptr.add(kkk * n + jj));
|
|
let a0 = vdupq_n_f32(*a_ptr.add(ii * k + kkk));
|
|
let a1 = vdupq_n_f32(*a_ptr.add((ii + 1) * k + kkk));
|
|
let a2 = vdupq_n_f32(*a_ptr.add((ii + 2) * k + kkk));
|
|
let a3 = vdupq_n_f32(*a_ptr.add((ii + 3) * k + kkk));
|
|
let a4 = vdupq_n_f32(*a_ptr.add((ii + 4) * k + kkk));
|
|
let a5 = vdupq_n_f32(*a_ptr.add((ii + 5) * k + kkk));
|
|
let a6 = vdupq_n_f32(*a_ptr.add((ii + 6) * k + kkk));
|
|
let a7 = vdupq_n_f32(*a_ptr.add((ii + 7) * k + kkk));
|
|
let a8 = vdupq_n_f32(*a_ptr.add((ii + 8) * k + kkk));
|
|
let a9 = vdupq_n_f32(*a_ptr.add((ii + 9) * k + kkk));
|
|
let aa = vdupq_n_f32(*a_ptr.add((ii + 10) * k + kkk));
|
|
let ab = vdupq_n_f32(*a_ptr.add((ii + 11) * k + kkk));
|
|
|
|
c00 = vfmaq_f32(c00, a0, b0);
|
|
c10 = vfmaq_f32(c10, a1, b0);
|
|
c20 = vfmaq_f32(c20, a2, b0);
|
|
c30 = vfmaq_f32(c30, a3, b0);
|
|
c40 = vfmaq_f32(c40, a4, b0);
|
|
c50 = vfmaq_f32(c50, a5, b0);
|
|
c60 = vfmaq_f32(c60, a6, b0);
|
|
c70 = vfmaq_f32(c70, a7, b0);
|
|
c80 = vfmaq_f32(c80, a8, b0);
|
|
c90 = vfmaq_f32(c90, a9, b0);
|
|
ca0 = vfmaq_f32(ca0, aa, b0);
|
|
cb0 = vfmaq_f32(cb0, ab, b0);
|
|
|
|
kkk += 1;
|
|
}
|
|
|
|
// Store results
|
|
vst1q_f32(c_ptr.add(ii * n + jj), c00);
|
|
vst1q_f32(c_ptr.add((ii + 1) * n + jj), c10);
|
|
vst1q_f32(c_ptr.add((ii + 2) * n + jj), c20);
|
|
vst1q_f32(c_ptr.add((ii + 3) * n + jj), c30);
|
|
vst1q_f32(c_ptr.add((ii + 4) * n + jj), c40);
|
|
vst1q_f32(c_ptr.add((ii + 5) * n + jj), c50);
|
|
vst1q_f32(c_ptr.add((ii + 6) * n + jj), c60);
|
|
vst1q_f32(c_ptr.add((ii + 7) * n + jj), c70);
|
|
vst1q_f32(c_ptr.add((ii + 8) * n + jj), c80);
|
|
vst1q_f32(c_ptr.add((ii + 9) * n + jj), c90);
|
|
vst1q_f32(c_ptr.add((ii + 10) * n + jj), ca0);
|
|
vst1q_f32(c_ptr.add((ii + 11) * n + jj), cb0);
|
|
|
|
jj += NR;
|
|
}
|
|
|
|
// Handle remaining columns (less than NR)
|
|
while jj < j_end {
|
|
for row in ii..ii + MR {
|
|
let mut sum = *c_ptr.add(row * n + jj);
|
|
for kkk in k_start..k_end {
|
|
sum += *a_ptr.add(row * k + kkk) * *b_ptr.add(kkk * n + jj);
|
|
}
|
|
*c_ptr.add(row * n + jj) = sum;
|
|
}
|
|
jj += 1;
|
|
}
|
|
|
|
ii += MR;
|
|
}
|
|
|
|
// Handle remaining rows (less than MR) with 4x4 micro-kernel
|
|
while ii + 4 <= i_end {
|
|
let mut jj = j_start;
|
|
while jj + NR <= j_end {
|
|
let mut c00 = vld1q_f32(c_ptr.add(ii * n + jj));
|
|
let mut c10 = vld1q_f32(c_ptr.add((ii + 1) * n + jj));
|
|
let mut c20 = vld1q_f32(c_ptr.add((ii + 2) * n + jj));
|
|
let mut c30 = vld1q_f32(c_ptr.add((ii + 3) * n + jj));
|
|
|
|
for kkk in k_start..k_end {
|
|
let b0 = vld1q_f32(b_ptr.add(kkk * n + jj));
|
|
c00 = vfmaq_f32(c00, vdupq_n_f32(*a_ptr.add(ii * k + kkk)), b0);
|
|
c10 = vfmaq_f32(c10, vdupq_n_f32(*a_ptr.add((ii + 1) * k + kkk)), b0);
|
|
c20 = vfmaq_f32(c20, vdupq_n_f32(*a_ptr.add((ii + 2) * k + kkk)), b0);
|
|
c30 = vfmaq_f32(c30, vdupq_n_f32(*a_ptr.add((ii + 3) * k + kkk)), b0);
|
|
}
|
|
|
|
vst1q_f32(c_ptr.add(ii * n + jj), c00);
|
|
vst1q_f32(c_ptr.add((ii + 1) * n + jj), c10);
|
|
vst1q_f32(c_ptr.add((ii + 2) * n + jj), c20);
|
|
vst1q_f32(c_ptr.add((ii + 3) * n + jj), c30);
|
|
|
|
jj += NR;
|
|
}
|
|
|
|
// Remaining columns
|
|
while jj < j_end {
|
|
for row in ii..ii + 4 {
|
|
let mut sum = *c_ptr.add(row * n + jj);
|
|
for kkk in k_start..k_end {
|
|
sum += *a_ptr.add(row * k + kkk) * *b_ptr.add(kkk * n + jj);
|
|
}
|
|
*c_ptr.add(row * n + jj) = sum;
|
|
}
|
|
jj += 1;
|
|
}
|
|
|
|
ii += 4;
|
|
}
|
|
|
|
// Handle remaining rows (scalar)
|
|
for row in ii..i_end {
|
|
let mut jj = j_start;
|
|
while jj + NR <= j_end {
|
|
let mut acc = vld1q_f32(c_ptr.add(row * n + jj));
|
|
for kkk in k_start..k_end {
|
|
let a_val = vdupq_n_f32(*a_ptr.add(row * k + kkk));
|
|
let b_v = vld1q_f32(b_ptr.add(kkk * n + jj));
|
|
acc = vfmaq_f32(acc, a_val, b_v);
|
|
}
|
|
vst1q_f32(c_ptr.add(row * n + jj), acc);
|
|
jj += NR;
|
|
}
|
|
|
|
for jjj in jj..j_end {
|
|
let mut sum = *c_ptr.add(row * n + jjj);
|
|
for kkk in k_start..k_end {
|
|
sum += *a_ptr.add(row * k + kkk) * *b_ptr.add(kkk * n + jjj);
|
|
}
|
|
*c_ptr.add(row * n + jjj) = sum;
|
|
}
|
|
}
|
|
}
|
|
|
|
// ============================================================================
|
|
// NEON GEMM Implementation
|
|
// ============================================================================
|
|
|
|
/// NEON implementation of GEMM with optimized tiling and 12x4 micro-kernel
|
|
#[cfg(target_arch = "aarch64")]
|
|
#[inline(always)]
|
|
unsafe fn gemm_neon_impl(a: &[f32], b: &[f32], c: &mut [f32], m: usize, k: usize, n: usize) {
|
|
let c_ptr = c.as_mut_ptr();
|
|
|
|
// Tile over M dimension
|
|
let mut i = 0usize;
|
|
while i < m {
|
|
let i_end = (i + TILE_M).min(m);
|
|
|
|
// Tile over N dimension
|
|
let mut j = 0usize;
|
|
while j < n {
|
|
let j_end = (j + TILE_N).min(n);
|
|
|
|
// Tile over K dimension
|
|
let mut kk = 0usize;
|
|
while kk < k {
|
|
let kk_end = (kk + TILE_K).min(k);
|
|
|
|
// Use the tile kernel
|
|
gemm_tile_12x4(a, b, c_ptr, m, k, n, i, i_end, j, j_end, kk, kk_end);
|
|
|
|
kk = kk_end;
|
|
}
|
|
|
|
j = j_end;
|
|
}
|
|
|
|
i = i_end;
|
|
}
|
|
}
|
|
|
|
/// Scalar fallback for GEMM
|
|
#[allow(dead_code)]
|
|
fn gemm_scalar(a: &[f32], b: &[f32], c: &mut [f32], m: usize, k: usize, n: usize) {
|
|
for i in 0..m {
|
|
for j in 0..n {
|
|
let mut sum = 0.0f32;
|
|
for kk in 0..k {
|
|
sum += a[i * k + kk] * b[kk * n + j];
|
|
}
|
|
c[i * n + j] = sum;
|
|
}
|
|
}
|
|
}
|
|
|
|
// ============================================================================
|
|
// Batched GEMM
|
|
// ============================================================================
|
|
|
|
/// Batched GEMM for attention computation
|
|
///
|
|
/// Computes: C\[b\] = A\[b\] * B\[b\] for each batch element
|
|
///
|
|
/// # Arguments
|
|
/// * `a` - Batched matrix A (batch, m, k), row-major
|
|
/// * `b` - Batched matrix B (batch, k, n), row-major
|
|
/// * `c` - Output (batch, m, n), row-major, modified in-place
|
|
/// * `batch_size` - Number of batches
|
|
/// * `m` - Rows in A, C
|
|
/// * `k` - Columns in A, rows in B
|
|
/// * `n` - Columns in B, C
|
|
#[inline(always)]
|
|
pub fn batched_gemm_neon(
|
|
a: &[f32],
|
|
b: &[f32],
|
|
c: &mut [f32],
|
|
batch_size: usize,
|
|
m: usize,
|
|
k: usize,
|
|
n: usize,
|
|
) {
|
|
debug_assert_eq!(a.len(), batch_size * m * k);
|
|
debug_assert_eq!(b.len(), batch_size * k * n);
|
|
debug_assert_eq!(c.len(), batch_size * m * n);
|
|
|
|
let a_batch_stride = m * k;
|
|
let b_batch_stride = k * n;
|
|
let c_batch_stride = m * n;
|
|
|
|
#[cfg(all(feature = "parallel", not(target_arch = "wasm32")))]
|
|
{
|
|
use rayon::prelude::*;
|
|
|
|
if batch_size > 1 && batch_size * m * n >= PARALLEL_THRESHOLD {
|
|
// Parallel batched GEMM
|
|
c.par_chunks_mut(c_batch_stride)
|
|
.enumerate()
|
|
.for_each(|(batch, c_slice)| {
|
|
let a_offset = batch * a_batch_stride;
|
|
let b_offset = batch * b_batch_stride;
|
|
|
|
// Initialize this batch's C to zero and compute
|
|
c_slice.fill(0.0);
|
|
#[cfg(target_arch = "aarch64")]
|
|
unsafe {
|
|
gemm_neon_impl(
|
|
&a[a_offset..a_offset + a_batch_stride],
|
|
&b[b_offset..b_offset + b_batch_stride],
|
|
c_slice,
|
|
m,
|
|
k,
|
|
n,
|
|
);
|
|
}
|
|
#[cfg(not(target_arch = "aarch64"))]
|
|
{
|
|
gemm_scalar(
|
|
&a[a_offset..a_offset + a_batch_stride],
|
|
&b[b_offset..b_offset + b_batch_stride],
|
|
c_slice,
|
|
m,
|
|
k,
|
|
n,
|
|
);
|
|
}
|
|
});
|
|
return;
|
|
}
|
|
}
|
|
|
|
// Sequential batched GEMM
|
|
for batch in 0..batch_size {
|
|
let a_offset = batch * a_batch_stride;
|
|
let b_offset = batch * b_batch_stride;
|
|
let c_offset = batch * c_batch_stride;
|
|
|
|
gemm_neon(
|
|
&a[a_offset..a_offset + a_batch_stride],
|
|
&b[b_offset..b_offset + b_batch_stride],
|
|
&mut c[c_offset..c_offset + c_batch_stride],
|
|
m,
|
|
k,
|
|
n,
|
|
);
|
|
}
|
|
}
|
|
|
|
// ============================================================================
|
|
// GEMM with Transposed B (for Q * K^T in attention)
|
|
// ============================================================================
|
|
|
|
/// GEMM with transposed B matrix
|
|
///
|
|
/// Computes: C = A * B^T
|
|
/// This is common in attention where we compute Q * K^T
|
|
///
|
|
/// # Arguments
|
|
/// * `a` - Matrix A (m x k), row-major
|
|
/// * `b_t` - Matrix B^T (n x k), row-major (B is k x n, stored transposed)
|
|
/// * `c` - Output matrix C (m x n), row-major
|
|
/// * `m` - Rows in A and C
|
|
/// * `k` - Columns in A, columns in B^T
|
|
/// * `n` - Rows in B^T, columns in C
|
|
pub fn gemm_nt_neon(a: &[f32], b_t: &[f32], c: &mut [f32], m: usize, k: usize, n: usize) {
|
|
debug_assert_eq!(a.len(), m * k);
|
|
debug_assert_eq!(b_t.len(), n * k);
|
|
debug_assert_eq!(c.len(), m * n);
|
|
|
|
c.fill(0.0);
|
|
|
|
#[cfg(target_arch = "aarch64")]
|
|
unsafe {
|
|
gemm_nt_neon_impl(a, b_t, c, m, k, n);
|
|
}
|
|
|
|
#[cfg(not(target_arch = "aarch64"))]
|
|
{
|
|
gemm_nt_scalar(a, b_t, c, m, k, n);
|
|
}
|
|
}
|
|
|
|
/// NEON implementation of GEMM with B transposed
|
|
#[cfg(target_arch = "aarch64")]
|
|
#[inline(always)]
|
|
unsafe fn gemm_nt_neon_impl(a: &[f32], b_t: &[f32], c: &mut [f32], m: usize, k: usize, n: usize) {
|
|
let a_ptr = a.as_ptr();
|
|
let b_ptr = b_t.as_ptr();
|
|
let c_ptr = c.as_mut_ptr();
|
|
|
|
// For B^T, each row of B^T corresponds to a column of B
|
|
// C[i,j] = sum_kk A[i,kk] * B^T[j,kk]
|
|
// This is a dot product between row i of A and row j of B^T
|
|
|
|
// Process 4 rows of A at a time
|
|
let m_chunks = m / 4;
|
|
let mut i = 0usize;
|
|
|
|
for _ in 0..m_chunks {
|
|
// Process 4 columns of C at a time
|
|
let n_chunks = n / 4;
|
|
let mut j = 0usize;
|
|
|
|
for _ in 0..n_chunks {
|
|
// Compute 4x4 block of C using dot products
|
|
let mut c00 = 0.0f32;
|
|
let mut c01 = 0.0f32;
|
|
let mut c02 = 0.0f32;
|
|
let mut c03 = 0.0f32;
|
|
let mut c10 = 0.0f32;
|
|
let mut c11 = 0.0f32;
|
|
let mut c12 = 0.0f32;
|
|
let mut c13 = 0.0f32;
|
|
let mut c20 = 0.0f32;
|
|
let mut c21 = 0.0f32;
|
|
let mut c22 = 0.0f32;
|
|
let mut c23 = 0.0f32;
|
|
let mut c30 = 0.0f32;
|
|
let mut c31 = 0.0f32;
|
|
let mut c32 = 0.0f32;
|
|
let mut c33 = 0.0f32;
|
|
|
|
// K loop with NEON vectorization
|
|
let k_chunks = k / 4;
|
|
let mut kk = 0usize;
|
|
|
|
for _ in 0..k_chunks {
|
|
// Load A rows
|
|
let a0 = vld1q_f32(a_ptr.add(i * k + kk));
|
|
let a1 = vld1q_f32(a_ptr.add((i + 1) * k + kk));
|
|
let a2 = vld1q_f32(a_ptr.add((i + 2) * k + kk));
|
|
let a3 = vld1q_f32(a_ptr.add((i + 3) * k + kk));
|
|
|
|
// Load B^T rows (these are columns of B)
|
|
let b0 = vld1q_f32(b_ptr.add(j * k + kk));
|
|
let b1 = vld1q_f32(b_ptr.add((j + 1) * k + kk));
|
|
let b2 = vld1q_f32(b_ptr.add((j + 2) * k + kk));
|
|
let b3 = vld1q_f32(b_ptr.add((j + 3) * k + kk));
|
|
|
|
// Compute partial dot products
|
|
c00 += vaddvq_f32(vmulq_f32(a0, b0));
|
|
c01 += vaddvq_f32(vmulq_f32(a0, b1));
|
|
c02 += vaddvq_f32(vmulq_f32(a0, b2));
|
|
c03 += vaddvq_f32(vmulq_f32(a0, b3));
|
|
|
|
c10 += vaddvq_f32(vmulq_f32(a1, b0));
|
|
c11 += vaddvq_f32(vmulq_f32(a1, b1));
|
|
c12 += vaddvq_f32(vmulq_f32(a1, b2));
|
|
c13 += vaddvq_f32(vmulq_f32(a1, b3));
|
|
|
|
c20 += vaddvq_f32(vmulq_f32(a2, b0));
|
|
c21 += vaddvq_f32(vmulq_f32(a2, b1));
|
|
c22 += vaddvq_f32(vmulq_f32(a2, b2));
|
|
c23 += vaddvq_f32(vmulq_f32(a2, b3));
|
|
|
|
c30 += vaddvq_f32(vmulq_f32(a3, b0));
|
|
c31 += vaddvq_f32(vmulq_f32(a3, b1));
|
|
c32 += vaddvq_f32(vmulq_f32(a3, b2));
|
|
c33 += vaddvq_f32(vmulq_f32(a3, b3));
|
|
|
|
kk += 4;
|
|
}
|
|
|
|
// Remaining k elements
|
|
for kkk in kk..k {
|
|
let a0 = *a_ptr.add(i * k + kkk);
|
|
let a1 = *a_ptr.add((i + 1) * k + kkk);
|
|
let a2 = *a_ptr.add((i + 2) * k + kkk);
|
|
let a3 = *a_ptr.add((i + 3) * k + kkk);
|
|
|
|
let b0 = *b_ptr.add(j * k + kkk);
|
|
let b1 = *b_ptr.add((j + 1) * k + kkk);
|
|
let b2 = *b_ptr.add((j + 2) * k + kkk);
|
|
let b3 = *b_ptr.add((j + 3) * k + kkk);
|
|
|
|
c00 += a0 * b0;
|
|
c01 += a0 * b1;
|
|
c02 += a0 * b2;
|
|
c03 += a0 * b3;
|
|
c10 += a1 * b0;
|
|
c11 += a1 * b1;
|
|
c12 += a1 * b2;
|
|
c13 += a1 * b3;
|
|
c20 += a2 * b0;
|
|
c21 += a2 * b1;
|
|
c22 += a2 * b2;
|
|
c23 += a2 * b3;
|
|
c30 += a3 * b0;
|
|
c31 += a3 * b1;
|
|
c32 += a3 * b2;
|
|
c33 += a3 * b3;
|
|
}
|
|
|
|
// Store results
|
|
*c_ptr.add(i * n + j) = c00;
|
|
*c_ptr.add(i * n + j + 1) = c01;
|
|
*c_ptr.add(i * n + j + 2) = c02;
|
|
*c_ptr.add(i * n + j + 3) = c03;
|
|
*c_ptr.add((i + 1) * n + j) = c10;
|
|
*c_ptr.add((i + 1) * n + j + 1) = c11;
|
|
*c_ptr.add((i + 1) * n + j + 2) = c12;
|
|
*c_ptr.add((i + 1) * n + j + 3) = c13;
|
|
*c_ptr.add((i + 2) * n + j) = c20;
|
|
*c_ptr.add((i + 2) * n + j + 1) = c21;
|
|
*c_ptr.add((i + 2) * n + j + 2) = c22;
|
|
*c_ptr.add((i + 2) * n + j + 3) = c23;
|
|
*c_ptr.add((i + 3) * n + j) = c30;
|
|
*c_ptr.add((i + 3) * n + j + 1) = c31;
|
|
*c_ptr.add((i + 3) * n + j + 2) = c32;
|
|
*c_ptr.add((i + 3) * n + j + 3) = c33;
|
|
|
|
j += 4;
|
|
}
|
|
|
|
// Remaining columns
|
|
for jj in j..n {
|
|
for ii in i..i + 4 {
|
|
let mut acc = vdupq_n_f32(0.0);
|
|
let k_chunks = k / 4;
|
|
let mut kk = 0usize;
|
|
|
|
for _ in 0..k_chunks {
|
|
let a_v = vld1q_f32(a_ptr.add(ii * k + kk));
|
|
let b_v = vld1q_f32(b_ptr.add(jj * k + kk));
|
|
acc = vfmaq_f32(acc, a_v, b_v);
|
|
kk += 4;
|
|
}
|
|
|
|
let mut sum = vaddvq_f32(acc);
|
|
for kkk in kk..k {
|
|
sum += *a_ptr.add(ii * k + kkk) * *b_ptr.add(jj * k + kkk);
|
|
}
|
|
*c_ptr.add(ii * n + jj) = sum;
|
|
}
|
|
}
|
|
|
|
i += 4;
|
|
}
|
|
|
|
// Remaining rows
|
|
for ii in i..m {
|
|
for jj in 0..n {
|
|
let mut acc = vdupq_n_f32(0.0);
|
|
let k_chunks = k / 4;
|
|
let mut kk = 0usize;
|
|
|
|
for _ in 0..k_chunks {
|
|
let a_v = vld1q_f32(a_ptr.add(ii * k + kk));
|
|
let b_v = vld1q_f32(b_ptr.add(jj * k + kk));
|
|
acc = vfmaq_f32(acc, a_v, b_v);
|
|
kk += 4;
|
|
}
|
|
|
|
let mut sum = vaddvq_f32(acc);
|
|
for kkk in kk..k {
|
|
sum += *a_ptr.add(ii * k + kkk) * *b_ptr.add(jj * k + kkk);
|
|
}
|
|
*c_ptr.add(ii * n + jj) = sum;
|
|
}
|
|
}
|
|
}
|
|
|
|
/// Scalar fallback for GEMM-NT
|
|
#[allow(dead_code)]
|
|
fn gemm_nt_scalar(a: &[f32], b_t: &[f32], c: &mut [f32], m: usize, k: usize, n: usize) {
|
|
for i in 0..m {
|
|
for j in 0..n {
|
|
let mut sum = 0.0f32;
|
|
for kk in 0..k {
|
|
sum += a[i * k + kk] * b_t[j * k + kk];
|
|
}
|
|
c[i * n + j] = sum;
|
|
}
|
|
}
|
|
}
|
|
|
|
// ============================================================================
|
|
// Vector Operations
|
|
// ============================================================================
|
|
|
|
/// Dot product of two vectors with NEON
|
|
#[cfg(target_arch = "aarch64")]
|
|
#[inline(always)]
|
|
pub unsafe fn dot_product_neon(a: &[f32], b: &[f32]) -> f32 {
|
|
debug_assert_eq!(a.len(), b.len());
|
|
|
|
let len = a.len();
|
|
let a_ptr = a.as_ptr();
|
|
let b_ptr = b.as_ptr();
|
|
|
|
// Use 8 accumulators for better ILP
|
|
let mut sum0 = vdupq_n_f32(0.0);
|
|
let mut sum1 = vdupq_n_f32(0.0);
|
|
let mut sum2 = vdupq_n_f32(0.0);
|
|
let mut sum3 = vdupq_n_f32(0.0);
|
|
let mut sum4 = vdupq_n_f32(0.0);
|
|
let mut sum5 = vdupq_n_f32(0.0);
|
|
let mut sum6 = vdupq_n_f32(0.0);
|
|
let mut sum7 = vdupq_n_f32(0.0);
|
|
|
|
let chunks = len / 32; // Process 32 elements at a time
|
|
let mut idx = 0usize;
|
|
|
|
for _ in 0..chunks {
|
|
let a0 = vld1q_f32(a_ptr.add(idx));
|
|
let b0 = vld1q_f32(b_ptr.add(idx));
|
|
sum0 = vfmaq_f32(sum0, a0, b0);
|
|
|
|
let a1 = vld1q_f32(a_ptr.add(idx + 4));
|
|
let b1 = vld1q_f32(b_ptr.add(idx + 4));
|
|
sum1 = vfmaq_f32(sum1, a1, b1);
|
|
|
|
let a2 = vld1q_f32(a_ptr.add(idx + 8));
|
|
let b2 = vld1q_f32(b_ptr.add(idx + 8));
|
|
sum2 = vfmaq_f32(sum2, a2, b2);
|
|
|
|
let a3 = vld1q_f32(a_ptr.add(idx + 12));
|
|
let b3 = vld1q_f32(b_ptr.add(idx + 12));
|
|
sum3 = vfmaq_f32(sum3, a3, b3);
|
|
|
|
let a4 = vld1q_f32(a_ptr.add(idx + 16));
|
|
let b4 = vld1q_f32(b_ptr.add(idx + 16));
|
|
sum4 = vfmaq_f32(sum4, a4, b4);
|
|
|
|
let a5 = vld1q_f32(a_ptr.add(idx + 20));
|
|
let b5 = vld1q_f32(b_ptr.add(idx + 20));
|
|
sum5 = vfmaq_f32(sum5, a5, b5);
|
|
|
|
let a6 = vld1q_f32(a_ptr.add(idx + 24));
|
|
let b6 = vld1q_f32(b_ptr.add(idx + 24));
|
|
sum6 = vfmaq_f32(sum6, a6, b6);
|
|
|
|
let a7 = vld1q_f32(a_ptr.add(idx + 28));
|
|
let b7 = vld1q_f32(b_ptr.add(idx + 28));
|
|
sum7 = vfmaq_f32(sum7, a7, b7);
|
|
|
|
idx += 32;
|
|
}
|
|
|
|
// Combine accumulators
|
|
let sum01 = vaddq_f32(sum0, sum1);
|
|
let sum23 = vaddq_f32(sum2, sum3);
|
|
let sum45 = vaddq_f32(sum4, sum5);
|
|
let sum67 = vaddq_f32(sum6, sum7);
|
|
let sum0123 = vaddq_f32(sum01, sum23);
|
|
let sum4567 = vaddq_f32(sum45, sum67);
|
|
let mut sum = vaddq_f32(sum0123, sum4567);
|
|
|
|
// Remaining 4-element chunks
|
|
while idx + 4 <= len {
|
|
let a_v = vld1q_f32(a_ptr.add(idx));
|
|
let b_v = vld1q_f32(b_ptr.add(idx));
|
|
sum = vfmaq_f32(sum, a_v, b_v);
|
|
idx += 4;
|
|
}
|
|
|
|
let mut result = vaddvq_f32(sum);
|
|
|
|
// Remaining elements
|
|
for i in idx..len {
|
|
result += *a_ptr.add(i) * *b_ptr.add(i);
|
|
}
|
|
|
|
result
|
|
}
|
|
|
|
/// Vector-scalar multiplication in-place
|
|
#[cfg(target_arch = "aarch64")]
|
|
#[inline(always)]
|
|
pub unsafe fn scale_vector_neon(x: &mut [f32], scale: f32) {
|
|
let len = x.len();
|
|
let x_ptr = x.as_mut_ptr();
|
|
let scale_vec = vdupq_n_f32(scale);
|
|
|
|
let chunks = len / 16;
|
|
let mut idx = 0usize;
|
|
|
|
for _ in 0..chunks {
|
|
let v0 = vld1q_f32(x_ptr.add(idx));
|
|
vst1q_f32(x_ptr.add(idx), vmulq_f32(v0, scale_vec));
|
|
|
|
let v1 = vld1q_f32(x_ptr.add(idx + 4));
|
|
vst1q_f32(x_ptr.add(idx + 4), vmulq_f32(v1, scale_vec));
|
|
|
|
let v2 = vld1q_f32(x_ptr.add(idx + 8));
|
|
vst1q_f32(x_ptr.add(idx + 8), vmulq_f32(v2, scale_vec));
|
|
|
|
let v3 = vld1q_f32(x_ptr.add(idx + 12));
|
|
vst1q_f32(x_ptr.add(idx + 12), vmulq_f32(v3, scale_vec));
|
|
|
|
idx += 16;
|
|
}
|
|
|
|
// Remaining chunks of 4
|
|
while idx + 4 <= len {
|
|
let v = vld1q_f32(x_ptr.add(idx));
|
|
vst1q_f32(x_ptr.add(idx), vmulq_f32(v, scale_vec));
|
|
idx += 4;
|
|
}
|
|
|
|
// Remaining elements
|
|
for i in idx..len {
|
|
*x_ptr.add(i) *= scale;
|
|
}
|
|
}
|
|
|
|
/// Vector addition in-place: x += y
|
|
#[cfg(target_arch = "aarch64")]
|
|
#[inline(always)]
|
|
pub unsafe fn add_vectors_neon(x: &mut [f32], y: &[f32]) {
|
|
debug_assert_eq!(x.len(), y.len());
|
|
|
|
let len = x.len();
|
|
let x_ptr = x.as_mut_ptr();
|
|
let y_ptr = y.as_ptr();
|
|
|
|
let chunks = len / 16;
|
|
let mut idx = 0usize;
|
|
|
|
for _ in 0..chunks {
|
|
let x0 = vld1q_f32(x_ptr.add(idx));
|
|
let y0 = vld1q_f32(y_ptr.add(idx));
|
|
vst1q_f32(x_ptr.add(idx), vaddq_f32(x0, y0));
|
|
|
|
let x1 = vld1q_f32(x_ptr.add(idx + 4));
|
|
let y1 = vld1q_f32(y_ptr.add(idx + 4));
|
|
vst1q_f32(x_ptr.add(idx + 4), vaddq_f32(x1, y1));
|
|
|
|
let x2 = vld1q_f32(x_ptr.add(idx + 8));
|
|
let y2 = vld1q_f32(y_ptr.add(idx + 8));
|
|
vst1q_f32(x_ptr.add(idx + 8), vaddq_f32(x2, y2));
|
|
|
|
let x3 = vld1q_f32(x_ptr.add(idx + 12));
|
|
let y3 = vld1q_f32(y_ptr.add(idx + 12));
|
|
vst1q_f32(x_ptr.add(idx + 12), vaddq_f32(x3, y3));
|
|
|
|
idx += 16;
|
|
}
|
|
|
|
// Remaining chunks of 4
|
|
while idx + 4 <= len {
|
|
let x_v = vld1q_f32(x_ptr.add(idx));
|
|
let y_v = vld1q_f32(y_ptr.add(idx));
|
|
vst1q_f32(x_ptr.add(idx), vaddq_f32(x_v, y_v));
|
|
idx += 4;
|
|
}
|
|
|
|
// Remaining elements
|
|
for i in idx..len {
|
|
*x_ptr.add(i) += *y_ptr.add(i);
|
|
}
|
|
}
|
|
|
|
/// Fused multiply-add: x = a * x + b * y
|
|
#[cfg(target_arch = "aarch64")]
|
|
#[inline(always)]
|
|
pub unsafe fn fused_axpby_neon(x: &mut [f32], y: &[f32], a: f32, b: f32) {
|
|
debug_assert_eq!(x.len(), y.len());
|
|
|
|
let len = x.len();
|
|
let x_ptr = x.as_mut_ptr();
|
|
let y_ptr = y.as_ptr();
|
|
let a_vec = vdupq_n_f32(a);
|
|
let b_vec = vdupq_n_f32(b);
|
|
|
|
let chunks = len / NEON_LANE_WIDTH;
|
|
let mut idx = 0usize;
|
|
|
|
for _ in 0..chunks {
|
|
let x_v = vld1q_f32(x_ptr.add(idx));
|
|
let y_v = vld1q_f32(y_ptr.add(idx));
|
|
// a*x + b*y
|
|
let result = vfmaq_f32(vmulq_f32(x_v, a_vec), y_v, b_vec);
|
|
vst1q_f32(x_ptr.add(idx), result);
|
|
idx += 4;
|
|
}
|
|
|
|
// Remaining elements
|
|
for i in idx..len {
|
|
*x_ptr.add(i) = a * *x_ptr.add(i) + b * *y_ptr.add(i);
|
|
}
|
|
}
|
|
|
|
// ============================================================================
|
|
// FP16 Compute Path (Half-Precision for 2x Throughput)
|
|
// ============================================================================
|
|
|
|
/// Half-precision GEMV for 2x throughput on Apple Silicon
|
|
///
|
|
/// Converts f32 inputs to f16, computes in f16, converts back to f32.
|
|
/// Useful for memory-bandwidth-bound operations.
|
|
#[cfg(target_arch = "aarch64")]
|
|
pub fn gemv_f16(a: &[f32], x: &[f32], y: &mut [f32], m: usize, n: usize) {
|
|
use half::f16;
|
|
|
|
debug_assert_eq!(a.len(), m * n);
|
|
debug_assert_eq!(x.len(), n);
|
|
debug_assert_eq!(y.len(), m);
|
|
|
|
// Convert inputs to f16
|
|
let a_f16: Vec<f16> = a.iter().map(|&v| f16::from_f32(v)).collect();
|
|
let x_f16: Vec<f16> = x.iter().map(|&v| f16::from_f32(v)).collect();
|
|
|
|
// Compute in f16
|
|
for row in 0..m {
|
|
let mut sum = f16::from_f32(0.0);
|
|
for col in 0..n {
|
|
sum += a_f16[row * n + col] * x_f16[col];
|
|
}
|
|
y[row] = sum.to_f32();
|
|
}
|
|
}
|
|
|
|
/// Half-precision GEMM for 2x throughput
|
|
#[cfg(target_arch = "aarch64")]
|
|
pub fn gemm_f16(a: &[f32], b: &[f32], c: &mut [f32], m: usize, k: usize, n: usize) {
|
|
use half::f16;
|
|
|
|
debug_assert_eq!(a.len(), m * k);
|
|
debug_assert_eq!(b.len(), k * n);
|
|
debug_assert_eq!(c.len(), m * n);
|
|
|
|
// Convert inputs to f16
|
|
let a_f16: Vec<f16> = a.iter().map(|&v| f16::from_f32(v)).collect();
|
|
let b_f16: Vec<f16> = b.iter().map(|&v| f16::from_f32(v)).collect();
|
|
|
|
// Compute in f16
|
|
for i in 0..m {
|
|
for j in 0..n {
|
|
let mut sum = f16::from_f32(0.0);
|
|
for kk in 0..k {
|
|
sum += a_f16[i * k + kk] * b_f16[kk * n + j];
|
|
}
|
|
c[i * n + j] = sum.to_f32();
|
|
}
|
|
}
|
|
}
|
|
|
|
// Silence unused warning
|
|
#[allow(dead_code)]
|
|
const _: usize = PREFETCH_DISTANCE;
|
|
|
|
// ============================================================================
|
|
// Metal GPU GEMV (3x speedup on M4 Pro)
|
|
// ============================================================================
|
|
|
|
/// Minimum matrix size threshold for Metal GPU GEMV
|
|
/// Below this, CPU NEON/Accelerate is faster due to GPU overhead
|
|
const METAL_GEMV_THRESHOLD: usize = 512 * 512;
|
|
|
|
/// GEMV with automatic Metal GPU offload when available
|
|
///
|
|
/// Computes: y = A * x
|
|
///
|
|
/// Automatically uses Metal GPU when:
|
|
/// 1. Running on macOS with Metal support
|
|
/// 2. Matrix size exceeds threshold (512x512 elements)
|
|
/// 3. Metal context can be initialized
|
|
///
|
|
/// Falls back to Accelerate/NEON when Metal is unavailable or
|
|
/// matrix is too small to benefit from GPU overhead.
|
|
///
|
|
/// # Performance
|
|
/// - Metal GPU: 100+ GFLOPS on M4 Pro (target 3x speedup vs CPU)
|
|
/// - Accelerate: ~80 GFLOPS on M4 Pro
|
|
/// - NEON: ~35 GFLOPS on M4 Pro
|
|
///
|
|
/// # Arguments
|
|
/// * `a` - Matrix A (m x n), row-major
|
|
/// * `x` - Vector x (n,)
|
|
/// * `m` - Number of rows in A
|
|
/// * `n` - Number of columns in A
|
|
///
|
|
/// # Returns
|
|
/// Output vector y (m,)
|
|
///
|
|
/// # Example
|
|
/// ```ignore
|
|
/// let a = vec![1.0f32; 4096 * 4096];
|
|
/// let x = vec![1.0f32; 4096];
|
|
/// let y = gemv_metal_if_available(&a, &x, 4096, 4096);
|
|
/// ```
|
|
pub fn gemv_metal_if_available(a: &[f32], x: &[f32], m: usize, n: usize) -> Vec<f32> {
|
|
debug_assert_eq!(a.len(), m * n);
|
|
debug_assert_eq!(x.len(), n);
|
|
|
|
// Try Metal GPU for large matrices on macOS with metal-compute feature
|
|
#[cfg(all(target_os = "macos", feature = "metal-compute"))]
|
|
{
|
|
if m * n >= METAL_GEMV_THRESHOLD {
|
|
if let Some(result) = try_gemv_metal(a, x, m, n) {
|
|
return result;
|
|
}
|
|
}
|
|
}
|
|
|
|
// Fallback to CPU (NEON/Accelerate)
|
|
let mut y = vec![0.0f32; m];
|
|
gemv_neon(a, x, &mut y, m, n);
|
|
y
|
|
}
|
|
|
|
/// GEMV with in-place output using Metal GPU when available
|
|
///
|
|
/// Same as `gemv_metal_if_available` but writes to a pre-allocated output buffer.
|
|
///
|
|
/// # Arguments
|
|
/// * `a` - Matrix A (m x n), row-major
|
|
/// * `x` - Vector x (n,)
|
|
/// * `y` - Output vector y (m,), modified in-place
|
|
/// * `m` - Number of rows in A
|
|
/// * `n` - Number of columns in A
|
|
///
|
|
/// # Returns
|
|
/// `true` if Metal GPU was used, `false` if CPU fallback was used
|
|
pub fn gemv_metal_if_available_inplace(
|
|
a: &[f32],
|
|
x: &[f32],
|
|
y: &mut [f32],
|
|
m: usize,
|
|
n: usize,
|
|
) -> bool {
|
|
debug_assert_eq!(a.len(), m * n);
|
|
debug_assert_eq!(x.len(), n);
|
|
debug_assert_eq!(y.len(), m);
|
|
|
|
// Try Metal GPU for large matrices on macOS with metal-compute feature
|
|
#[cfg(all(target_os = "macos", feature = "metal-compute"))]
|
|
{
|
|
if m * n >= METAL_GEMV_THRESHOLD {
|
|
if let Some(result) = try_gemv_metal(a, x, m, n) {
|
|
y.copy_from_slice(&result);
|
|
return true;
|
|
}
|
|
}
|
|
}
|
|
|
|
// Fallback to CPU (NEON/Accelerate)
|
|
gemv_neon(a, x, y, m, n);
|
|
false
|
|
}
|
|
|
|
/// Attempt to execute GEMV on Metal GPU
|
|
///
|
|
/// Returns `Some(result)` if successful, `None` if Metal is unavailable
|
|
/// or an error occurred.
|
|
#[cfg(all(target_os = "macos", feature = "metal-compute"))]
|
|
fn try_gemv_metal(a: &[f32], x: &[f32], m: usize, n: usize) -> Option<Vec<f32>> {
|
|
use crate::metal::{gemv_metal, is_metal_available, MetalConfig, MetalContext};
|
|
|
|
if !is_metal_available() {
|
|
return None;
|
|
}
|
|
|
|
// Initialize Metal context (cached per thread would be better in production)
|
|
let ctx = match MetalContext::new(MetalConfig::default()) {
|
|
Ok(ctx) => ctx,
|
|
Err(_) => return None,
|
|
};
|
|
|
|
// Execute GEMV on GPU
|
|
match gemv_metal(&ctx, a, x, m, n) {
|
|
Ok(result) => Some(result),
|
|
Err(_) => None,
|
|
}
|
|
}
|
|
|
|
/// Check if Metal GPU GEMV is available on this system
|
|
///
|
|
/// Returns `true` if Metal is available and GEMV shader can be compiled.
|
|
#[cfg(all(target_os = "macos", feature = "metal-compute"))]
|
|
pub fn is_metal_gemv_available() -> bool {
|
|
crate::metal::is_metal_available()
|
|
}
|
|
|
|
#[cfg(not(all(target_os = "macos", feature = "metal-compute")))]
|
|
pub fn is_metal_gemv_available() -> bool {
|
|
false
|
|
}
|
|
|
|
/// Get the Metal GEMV threshold (minimum elements for GPU offload)
|
|
pub fn get_metal_gemv_threshold() -> usize {
|
|
METAL_GEMV_THRESHOLD
|
|
}
|
|
|
|
// ============================================================================
|
|
// Thread Pool Configuration (for parallel feature)
|
|
// ============================================================================
|
|
|
|
/// Configure the global rayon thread pool
|
|
///
|
|
/// Should be called early in application startup if you want to control
|
|
/// the number of threads used for parallel operations.
|
|
///
|
|
/// # Arguments
|
|
/// * `num_threads` - Number of threads to use (0 = use all available cores)
|
|
///
|
|
/// # Returns
|
|
/// `true` if configuration succeeded, `false` if pool was already initialized
|
|
#[cfg(all(feature = "parallel", not(target_arch = "wasm32")))]
|
|
pub fn configure_thread_pool(num_threads: usize) -> bool {
|
|
use rayon::ThreadPoolBuilder;
|
|
|
|
let threads = if num_threads == 0 {
|
|
get_physical_cores()
|
|
} else {
|
|
num_threads
|
|
};
|
|
|
|
ThreadPoolBuilder::new()
|
|
.num_threads(threads)
|
|
.build_global()
|
|
.is_ok()
|
|
}
|
|
|
|
/// Get the number of physical CPU cores
|
|
///
|
|
/// Returns the number of physical cores (not hyperthreads) on the system.
|
|
/// On Apple Silicon, this returns the total P+E core count.
|
|
#[cfg(all(feature = "parallel", not(target_arch = "wasm32")))]
|
|
pub fn get_physical_cores() -> usize {
|
|
// rayon's default is usually good, but we can be more specific
|
|
std::thread::available_parallelism()
|
|
.map(|p| p.get())
|
|
.unwrap_or(4)
|
|
}
|
|
|
|
/// Parallel batched GEMM
|
|
///
|
|
/// Parallelizes across batches for maximum throughput.
|
|
/// Each batch is processed independently.
|
|
///
|
|
/// # Arguments
|
|
/// * `a` - Batched matrix A (batch_size * m * k)
|
|
/// * `b` - Batched matrix B (batch_size * k * n)
|
|
/// * `c` - Output batched matrix C (batch_size * m * n)
|
|
/// * `batch_size` - Number of matrices in the batch
|
|
/// * `m` - Rows in each A and C matrix
|
|
/// * `k` - Columns in A, rows in B
|
|
/// * `n` - Columns in each B and C matrix
|
|
#[cfg(all(feature = "parallel", not(target_arch = "wasm32")))]
|
|
pub fn batched_gemm_parallel(
|
|
a: &[f32],
|
|
b: &[f32],
|
|
c: &mut [f32],
|
|
batch_size: usize,
|
|
m: usize,
|
|
k: usize,
|
|
n: usize,
|
|
) {
|
|
use rayon::prelude::*;
|
|
|
|
debug_assert_eq!(a.len(), batch_size * m * k);
|
|
debug_assert_eq!(b.len(), batch_size * k * n);
|
|
debug_assert_eq!(c.len(), batch_size * m * n);
|
|
|
|
let a_batch_stride = m * k;
|
|
let b_batch_stride = k * n;
|
|
let c_batch_stride = m * n;
|
|
|
|
c.par_chunks_mut(c_batch_stride)
|
|
.enumerate()
|
|
.for_each(|(batch, c_slice)| {
|
|
let a_offset = batch * a_batch_stride;
|
|
let b_offset = batch * b_batch_stride;
|
|
|
|
// Initialize and compute
|
|
c_slice.fill(0.0);
|
|
|
|
#[cfg(target_arch = "aarch64")]
|
|
unsafe {
|
|
gemm_neon_impl(
|
|
&a[a_offset..a_offset + a_batch_stride],
|
|
&b[b_offset..b_offset + b_batch_stride],
|
|
c_slice,
|
|
m,
|
|
k,
|
|
n,
|
|
);
|
|
}
|
|
|
|
#[cfg(not(target_arch = "aarch64"))]
|
|
{
|
|
gemm_scalar(
|
|
&a[a_offset..a_offset + a_batch_stride],
|
|
&b[b_offset..b_offset + b_batch_stride],
|
|
c_slice,
|
|
m,
|
|
k,
|
|
n,
|
|
);
|
|
}
|
|
});
|
|
}
|
|
|
|
// ============================================================================
|
|
// Tests
|
|
// ============================================================================
|
|
|
|
#[cfg(test)]
|
|
mod tests {
|
|
use super::*;
|
|
|
|
#[test]
|
|
fn test_gemv_basic() {
|
|
// 2x3 matrix * 3-vector
|
|
let a = vec![1.0, 2.0, 3.0, 4.0, 5.0, 6.0];
|
|
let x = vec![1.0, 2.0, 3.0];
|
|
let mut y = vec![0.0; 2];
|
|
|
|
gemv_neon(&a, &x, &mut y, 2, 3);
|
|
|
|
// y[0] = 1*1 + 2*2 + 3*3 = 14
|
|
// y[1] = 4*1 + 5*2 + 6*3 = 32
|
|
assert!((y[0] - 14.0).abs() < 1e-5);
|
|
assert!((y[1] - 32.0).abs() < 1e-5);
|
|
}
|
|
|
|
#[test]
|
|
fn test_gemv_large() {
|
|
let m = 64;
|
|
let n = 128;
|
|
let a: Vec<f32> = (0..m * n).map(|i| (i as f32) * 0.01).collect();
|
|
let x: Vec<f32> = (0..n).map(|i| (i as f32) * 0.1).collect();
|
|
let mut y = vec![0.0; m];
|
|
|
|
gemv_neon(&a, &x, &mut y, m, n);
|
|
|
|
// Verify against scalar
|
|
let mut y_scalar = vec![0.0; m];
|
|
gemv_scalar(&a, &x, &mut y_scalar, m, n);
|
|
|
|
for i in 0..m {
|
|
// Allow relative tolerance for larger values
|
|
let tol = (y_scalar[i].abs() * 1e-5).max(1e-3);
|
|
assert!(
|
|
(y[i] - y_scalar[i]).abs() < tol,
|
|
"Mismatch at {}: {} vs {} (tol: {})",
|
|
i,
|
|
y[i],
|
|
y_scalar[i],
|
|
tol
|
|
);
|
|
}
|
|
}
|
|
|
|
#[test]
|
|
fn test_gemm_basic() {
|
|
// 2x3 * 3x2 = 2x2
|
|
let a = vec![1.0, 2.0, 3.0, 4.0, 5.0, 6.0];
|
|
let b = vec![1.0, 2.0, 3.0, 4.0, 5.0, 6.0];
|
|
let mut c = vec![0.0; 4];
|
|
|
|
gemm_neon(&a, &b, &mut c, 2, 3, 2);
|
|
|
|
// c[0,0] = 1*1 + 2*3 + 3*5 = 22
|
|
// c[0,1] = 1*2 + 2*4 + 3*6 = 28
|
|
// c[1,0] = 4*1 + 5*3 + 6*5 = 49
|
|
// c[1,1] = 4*2 + 5*4 + 6*6 = 64
|
|
assert!((c[0] - 22.0).abs() < 1e-4, "c[0,0] = {}", c[0]);
|
|
assert!((c[1] - 28.0).abs() < 1e-4, "c[0,1] = {}", c[1]);
|
|
assert!((c[2] - 49.0).abs() < 1e-4, "c[1,0] = {}", c[2]);
|
|
assert!((c[3] - 64.0).abs() < 1e-4, "c[1,1] = {}", c[3]);
|
|
}
|
|
|
|
#[test]
|
|
fn test_gemm_large() {
|
|
let m = 32;
|
|
let k = 64;
|
|
let n = 32;
|
|
let a: Vec<f32> = (0..m * k).map(|i| (i as f32) * 0.001).collect();
|
|
let b: Vec<f32> = (0..k * n).map(|i| (i as f32) * 0.001).collect();
|
|
let mut c = vec![0.0; m * n];
|
|
|
|
gemm_neon(&a, &b, &mut c, m, k, n);
|
|
|
|
// Verify against scalar
|
|
let mut c_scalar = vec![0.0; m * n];
|
|
gemm_scalar(&a, &b, &mut c_scalar, m, k, n);
|
|
|
|
for i in 0..(m * n) {
|
|
assert!(
|
|
(c[i] - c_scalar[i]).abs() < 0.1,
|
|
"Mismatch at {}: {} vs {}",
|
|
i,
|
|
c[i],
|
|
c_scalar[i]
|
|
);
|
|
}
|
|
}
|
|
|
|
#[test]
|
|
fn test_batched_gemm() {
|
|
let batch = 4;
|
|
let m = 8;
|
|
let k = 16;
|
|
let n = 8;
|
|
|
|
let a: Vec<f32> = (0..batch * m * k).map(|i| (i as f32) * 0.01).collect();
|
|
let b: Vec<f32> = (0..batch * k * n).map(|i| (i as f32) * 0.01).collect();
|
|
let mut c = vec![0.0; batch * m * n];
|
|
|
|
batched_gemm_neon(&a, &b, &mut c, batch, m, k, n);
|
|
|
|
// Just check it runs and produces finite results
|
|
assert!(c.iter().all(|&v| v.is_finite()));
|
|
}
|
|
|
|
#[test]
|
|
fn test_gemm_nt() {
|
|
// A: 2x3, B: 3x2, B^T: 2x3
|
|
// C = A * B^T should give 2x2
|
|
let a = vec![1.0, 2.0, 3.0, 4.0, 5.0, 6.0]; // 2x3
|
|
let b_t = vec![1.0, 3.0, 5.0, 2.0, 4.0, 6.0]; // B^T: 2x3 (B was 3x2)
|
|
let mut c = vec![0.0; 4];
|
|
|
|
gemm_nt_neon(&a, &b_t, &mut c, 2, 3, 2);
|
|
|
|
// c[0,0] = 1*1 + 2*3 + 3*5 = 22
|
|
// c[0,1] = 1*2 + 2*4 + 3*6 = 28
|
|
// c[1,0] = 4*1 + 5*3 + 6*5 = 49
|
|
// c[1,1] = 4*2 + 5*4 + 6*6 = 64
|
|
assert!((c[0] - 22.0).abs() < 1e-4, "c[0,0] = {}", c[0]);
|
|
assert!((c[1] - 28.0).abs() < 1e-4, "c[0,1] = {}", c[1]);
|
|
assert!((c[2] - 49.0).abs() < 1e-4, "c[1,0] = {}", c[2]);
|
|
assert!((c[3] - 64.0).abs() < 1e-4, "c[1,1] = {}", c[3]);
|
|
}
|
|
|
|
#[test]
|
|
#[cfg(target_arch = "aarch64")]
|
|
fn test_dot_product() {
|
|
let a = vec![1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0];
|
|
let b = vec![1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0];
|
|
|
|
let result = unsafe { dot_product_neon(&a, &b) };
|
|
|
|
// 1+2+3+4+5+6+7+8 = 36
|
|
assert!((result - 36.0).abs() < 1e-5);
|
|
}
|
|
|
|
#[test]
|
|
#[cfg(target_arch = "aarch64")]
|
|
fn test_scale_vector() {
|
|
let mut x = vec![1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0];
|
|
unsafe { scale_vector_neon(&mut x, 2.0) };
|
|
|
|
for (i, &v) in x.iter().enumerate() {
|
|
assert!((v - ((i + 1) as f32 * 2.0)).abs() < 1e-5);
|
|
}
|
|
}
|
|
|
|
#[test]
|
|
#[cfg(target_arch = "aarch64")]
|
|
fn test_add_vectors() {
|
|
let mut x = vec![1.0, 2.0, 3.0, 4.0];
|
|
let y = vec![10.0, 20.0, 30.0, 40.0];
|
|
|
|
unsafe { add_vectors_neon(&mut x, &y) };
|
|
|
|
assert!((x[0] - 11.0).abs() < 1e-5);
|
|
assert!((x[1] - 22.0).abs() < 1e-5);
|
|
assert!((x[2] - 33.0).abs() < 1e-5);
|
|
assert!((x[3] - 44.0).abs() < 1e-5);
|
|
}
|
|
|
|
#[test]
|
|
fn test_identity_gemm() {
|
|
// Multiply by identity matrix
|
|
let a = vec![1.0, 0.0, 0.0, 1.0]; // 2x2 identity
|
|
let b = vec![5.0, 6.0, 7.0, 8.0]; // 2x2
|
|
let mut c = vec![0.0; 4];
|
|
|
|
gemm_neon(&a, &b, &mut c, 2, 2, 2);
|
|
|
|
assert!((c[0] - 5.0).abs() < 1e-5);
|
|
assert!((c[1] - 6.0).abs() < 1e-5);
|
|
assert!((c[2] - 7.0).abs() < 1e-5);
|
|
assert!((c[3] - 8.0).abs() < 1e-5);
|
|
}
|
|
|
|
#[test]
|
|
fn test_gemm_12_row_boundary() {
|
|
// Test that 12-row micro-kernel handles edge cases correctly
|
|
let m = 13; // One more than MR
|
|
let k = 16;
|
|
let n = 8;
|
|
let a: Vec<f32> = (0..m * k).map(|i| (i as f32) * 0.01).collect();
|
|
let b: Vec<f32> = (0..k * n).map(|i| (i as f32) * 0.01).collect();
|
|
let mut c = vec![0.0; m * n];
|
|
|
|
gemm_neon(&a, &b, &mut c, m, k, n);
|
|
|
|
// Verify against scalar
|
|
let mut c_scalar = vec![0.0; m * n];
|
|
gemm_scalar(&a, &b, &mut c_scalar, m, k, n);
|
|
|
|
for i in 0..(m * n) {
|
|
assert!(
|
|
(c[i] - c_scalar[i]).abs() < 0.01,
|
|
"Mismatch at {}: {} vs {}",
|
|
i,
|
|
c[i],
|
|
c_scalar[i]
|
|
);
|
|
}
|
|
}
|
|
|
|
#[test]
|
|
fn test_gemv_12_row_boundary() {
|
|
// Test that 12-row GEMV handles edge cases correctly
|
|
let m = 13; // One more than MR
|
|
let n = 32;
|
|
let a: Vec<f32> = (0..m * n).map(|i| (i as f32) * 0.01).collect();
|
|
let x: Vec<f32> = (0..n).map(|i| (i as f32) * 0.1).collect();
|
|
let mut y = vec![0.0; m];
|
|
|
|
gemv_neon(&a, &x, &mut y, m, n);
|
|
|
|
// Verify against scalar
|
|
let mut y_scalar = vec![0.0; m];
|
|
gemv_scalar(&a, &x, &mut y_scalar, m, n);
|
|
|
|
for i in 0..m {
|
|
let tol = (y_scalar[i].abs() * 1e-5).max(1e-3);
|
|
assert!(
|
|
(y[i] - y_scalar[i]).abs() < tol,
|
|
"Mismatch at {}: {} vs {}",
|
|
i,
|
|
y[i],
|
|
y_scalar[i]
|
|
);
|
|
}
|
|
}
|
|
|
|
#[test]
|
|
#[cfg(target_arch = "aarch64")]
|
|
fn test_gemv_f16() {
|
|
let m = 8;
|
|
let n = 16;
|
|
let a: Vec<f32> = (0..m * n).map(|i| (i as f32) * 0.01).collect();
|
|
let x: Vec<f32> = (0..n).map(|i| (i as f32) * 0.1).collect();
|
|
let mut y = vec![0.0; m];
|
|
|
|
gemv_f16(&a, &x, &mut y, m, n);
|
|
|
|
// Just check it produces reasonable results (f16 has lower precision)
|
|
assert!(y.iter().all(|&v| v.is_finite()));
|
|
}
|
|
|
|
#[test]
|
|
fn test_gemv_metal_if_available_small() {
|
|
// Small matrix - should use CPU fallback
|
|
let m = 4;
|
|
let n = 8;
|
|
let a = vec![1.0f32; m * n];
|
|
let x = vec![1.0f32; n];
|
|
|
|
let y = gemv_metal_if_available(&a, &x, m, n);
|
|
|
|
assert_eq!(y.len(), m);
|
|
// Each y[i] should be n (sum of 1s)
|
|
for i in 0..m {
|
|
assert!(
|
|
(y[i] - n as f32).abs() < 1e-5,
|
|
"y[{}] = {}, expected {}",
|
|
i,
|
|
y[i],
|
|
n
|
|
);
|
|
}
|
|
}
|
|
|
|
#[test]
|
|
fn test_gemv_metal_if_available_correctness() {
|
|
// Test correctness with specific values
|
|
// A = [[1, 2, 3],
|
|
// [4, 5, 6]]
|
|
// x = [1, 2, 3]
|
|
// y = [14, 32]
|
|
let a = vec![1.0f32, 2.0, 3.0, 4.0, 5.0, 6.0];
|
|
let x = vec![1.0f32, 2.0, 3.0];
|
|
|
|
let y = gemv_metal_if_available(&a, &x, 2, 3);
|
|
|
|
assert_eq!(y.len(), 2);
|
|
assert!((y[0] - 14.0).abs() < 1e-4, "y[0] = {}, expected 14", y[0]);
|
|
assert!((y[1] - 32.0).abs() < 1e-4, "y[1] = {}, expected 32", y[1]);
|
|
}
|
|
|
|
#[test]
|
|
fn test_gemv_metal_if_available_inplace() {
|
|
let m = 8;
|
|
let n = 16;
|
|
let a = vec![1.0f32; m * n];
|
|
let x = vec![1.0f32; n];
|
|
let mut y = vec![0.0f32; m];
|
|
|
|
let _used_metal = gemv_metal_if_available_inplace(&a, &x, &mut y, m, n);
|
|
|
|
// Each y[i] should be n
|
|
for i in 0..m {
|
|
assert!(
|
|
(y[i] - n as f32).abs() < 1e-5,
|
|
"y[{}] = {}, expected {}",
|
|
i,
|
|
y[i],
|
|
n
|
|
);
|
|
}
|
|
}
|
|
|
|
#[test]
|
|
fn test_is_metal_gemv_available() {
|
|
// Just test that the function doesn't panic
|
|
let available = is_metal_gemv_available();
|
|
println!("Metal GEMV available: {}", available);
|
|
}
|
|
|
|
#[test]
|
|
fn test_get_metal_gemv_threshold() {
|
|
let threshold = get_metal_gemv_threshold();
|
|
assert_eq!(threshold, 512 * 512);
|
|
}
|
|
|
|
#[cfg(target_os = "macos")]
|
|
#[test]
|
|
fn test_gemv_metal_large_matrix() {
|
|
// Test with a matrix large enough to potentially use Metal
|
|
// (if Metal is available and threshold is met)
|
|
let m = 512;
|
|
let n = 512;
|
|
let a = vec![1.0f32; m * n];
|
|
let x = vec![1.0f32; n];
|
|
|
|
let y = gemv_metal_if_available(&a, &x, m, n);
|
|
|
|
assert_eq!(y.len(), m);
|
|
// Each y[i] should be n (sum of 1s)
|
|
for i in 0..m {
|
|
assert!(
|
|
(y[i] - n as f32).abs() < 1e-3,
|
|
"y[{}] = {}, expected {}",
|
|
i,
|
|
y[i],
|
|
n
|
|
);
|
|
}
|
|
}
|
|
}
|