b10236

metal: implement DSv4 Lightning Indexer (#25893)

• metal: implement F16 Lightning Indexer

• Implement GGML_OP_LIGHTNING_INDEXER for 128-dimensional, 64-head inputs
  with F32 queries and weights plus F16 keys and masks.
• Add tiled and tail kernels and test KV lengths around 8- and 64-element
  boundaries.

llama-bench (--mmap 1, -fa 1, -p 512, -n 128; d=0/10k/20k/30k):

Before:

• pp512: 153.73 ± 0.87 t/s
• tg128: 8.91 ± 0.04 t/s
• pp512 @ d10000: 73.90 ± 0.39 t/s
• tg128 @ d10000: 8.66 ± 0.03 t/s
• pp512 @ d20000: 45.83 ± 0.18 t/s
• tg128 @ d20000: 8.26 ± 0.03 t/s
• pp512 @ d30000: 33.40 ± 0.21 t/s
• tg128 @ d30000: 7.94 ± 0.01 t/s

After:

• pp512: 155.19 ± 0.91 t/s
• tg128: 8.95 ± 0.04 t/s
• pp512 @ d10000: 86.95 ± 0.69 t/s
• tg128 @ d10000: 9.00 ± 0.05 t/s
• pp512 @ d20000: 62.01 ± 0.45 t/s
• tg128 @ d20000: 8.68 ± 0.04 t/s
• pp512 @ d30000: 49.18 ± 0.33 t/s
• tg128 @ d30000: 8.60 ± 0.02 t/s

Assisted-by: Codex

• metal: stage Lightning Indexer K tiles

• Stage and dequantize K in F16 threadgroup memory before simdgroup matrix loads.
• Zero-fill partial tiles and guard stores so all KV segments use the same numerical path.
• Support F32, F16, BF16, Q4_0, Q4_1, Q5_0, Q5_1, and Q8_0 K caches.

llama-bench (--mmap 1, -fa on, -p 512, -n 128; d=0/10k/20k):

• pp512: 160.38 +/- 1.01 t/s
• tg128: 9.08 +/- 0.03 t/s
• pp512 @ d10000: 88.37 +/- 0.46 t/s
• tg128 @ d10000: 9.07 +/- 0.04 t/s
• pp512 @ d20000: 62.53 +/- 0.46 t/s
• tg128 @ d20000: 8.84 +/- 0.03 t/s

Assisted-by: Codex

• dedup Lightning Indexer constants, fix flaky test

• cont : fix whitespace

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Co-authored-by: forforever73 690105611@qq.com
Co-authored-by: Georgi Gerganov ggerganov@gmail.com

Website:

• https://llama.app

macOS/iOS:

• macOS Apple Silicon (arm64)
• macOS Apple Silicon (arm64, KleidiAI enabled) DISABLED
• macOS Intel (x64)
• iOS XCFramework

Linux:

• Ubuntu x64 (CPU)
• Ubuntu arm64 (CPU)
• Ubuntu s390x (CPU)
• Ubuntu x64 (Vulkan)
• Ubuntu arm64 (Vulkan)
• Ubuntu x64 (ROCm 7.2)
• Ubuntu x64 (OpenVINO)
• Ubuntu x64 (SYCL FP32)
• Ubuntu x64 (SYCL FP16)

Android:

• Android arm64 (CPU)

Windows:

• Windows x64 (CPU)
• Windows arm64 (CPU)
• Windows arm64 (OpenCL Adreno)
• Windows x64 (CUDA 12) - CUDA 12.4 DLLs
• Windows x64 (CUDA 13) - CUDA 13.3 DLLs
• Windows x64 (Vulkan)
• Windows x64 (OpenVINO)
• Windows x64 (SYCL)
• Windows x64 (HIP)

openEuler:

• DISABLED
• openEuler x86 (310p)
• openEuler x86 (910b, ACL Graph)
• openEuler aarch64 (310p)
• openEuler aarch64 (910b, ACL Graph)

UI:

• UI