b12094

hexagon: faster TOP_K for the backend sampler (#31279)

• hexagon: faster TOP_K for the backend sampler (skip tiles, then block scan)

Skip the bitonic sort for tiles whose max cannot reach the running k-th
best value, then replace the tile sort with top_k_scan(): reject 256-float
blocks with one HVX max-reduce and insert only surviving elements into a
sorted k-entry list. Used for k in 2..64 and rows wider than 1024, in both
the single-row and multi-row paths.

Ties keep the first-seen index. NaN is treated as -INF.

• hex-top-k: eliminate scalar reads from vtcm

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Co-authored-by: Max Krasnyansky maxk@qti.qualcomm.com

Website:

• https://llama.app

Attestations:

• https://github.com/ggml-org/llama.cpp/attestations/63400302

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 26.04 s390x (CPU)
• Ubuntu 26.04 s390x (zDNN)
• Ubuntu x64 (Vulkan)
• Ubuntu arm64 (Vulkan)
• Ubuntu x64 (CUDA 12) - CUDA 12.8 libraries
• Ubuntu x64 (CUDA 13) - CUDA 13.4 libraries
• Ubuntu arm64 (CUDA 13) - CUDA 13.4 libraries
• Ubuntu x64 (ROCm 10.0)
• Ubuntu x64 (OpenVINO)
• Ubuntu x64 (SYCL FP32)
• Ubuntu x64 (SYCL FP16)
• Linux arm64 (Snapdragon: CPU, Adreno GPU, Hexagon NPU) - setup guide

Android:

• Android arm64 (CPU)
• Android arm64 (Snapdragon: CPU, Adreno GPU, Hexagon NPU) - setup guide

Windows:

• Windows x64 (CPU)
• Windows arm64 (CPU)
• Windows arm64 (OpenCL Adreno)
• Windows x64 (CUDA 12) - CUDA 12.4 DLLs
• Windows x64 (CUDA 13) - CUDA 13.4 DLLs
• Windows arm64 (CUDA 13) - CUDA 13.4 DLLs
• Windows x64 (Vulkan)
• Windows arm64 (Vulkan)
• Windows x64 (OpenVINO)
• Windows x64 (SYCL)
• Windows x64 (ROCm 10.0)

openEuler:

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

UI:

• UI