* sycl : fused MoE mul_mat_vec_q for TG
Create an MMVQ kernel so ggml_sycl_mul_mat_id can consolidate
n_experts_used matmuls in a single kernel launch. The kernel
also reads expert IDs directly, removing a per-call host sync.
This is similar to the CUDA backend's ggml_cuda_mul_mat_vec_q*
paths.
All types supported in the current MMVQ are supported here as well:
Q2_K, Q3_K, Q4_K, Q5_K, Q6_K, Q4_0, Q4_1, Q5_0, Q5_1, Q8_0
It will fall back to the existing per-expert path when src0 has been rewritten
by opt_for_reorder(), and for any shape the fused path doesn't handle.
test-backend-ops passes for supported type/shape combos.
Benchmark: Qwen3-Next-35B-A3B Q4_K_M on Intel Arc B70 (SYCL0),
baseline 707c0b7a6, 16k context, -fa 0.
build/bin/llama-bench -hf unsloth/Qwen3.5-35B-A3B-GGUF:Q4_K_M \
-p 1024 -n 128 -d 16384 -ngl 99 -fa 0 -ub 2048 -r 2 -dev SYCL0
Before (3 runs on 707c0b7a6):
| test | run 1 | run 2 | run 3 |
| --------------- | ----------------:| ----------------:| ----------------:|
| pp1024 @ d16384 | 533.26 ± 4.87 | 535.20 ± 2.78 | 524.27 ± 3.10 |
| tg128 @ d16384 | 33.47 ± 0.02 | 33.31 ± 0.02 | 33.17 ± 0.05 |
After (3 runs on 707c0b7a6 + this patch):
| test | run 1 | run 2 | run 3 |
| --------------- | ----------------:| ----------------:| ----------------:|
| pp1024 @ d16384 | 534.06 ± 0.97 | 531.95 ± 0.02 | 520.94 ± 20.10 |
| tg128 @ d16384 | 45.85 ± 0.21 | 45.95 ± 0.45 | 46.22 ± 0.12 |
disclosure: Claude wrote it, but I reviewed and understand the implementation
(albeit my C is a little rusty).
* sycl: also support nvfp4 and mxfp4 expert types
* sycl: terser comments/nested dispatch in response to review
* sycl: more comment cleanup in mmvq.cpp/hpp
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Co-authored-by: Debian <aaron@openllmi.net.bots.is>
abotsis
60b68a6279