ggml-org/llama.cpp b12189

on GitHub

metal : fix GROUP_NORM for ne03 > 1 and non-contiguous inputs (#31852)

The kernel_group_norm_f32 kernel and its host dispatch ignored the
batch dimension (ne03) of the source tensor: only ngrp threadgroups
were dispatched and each normalized the flat range
[tgpiggs, (tgpig+1)gs) with gs = ne00ne01ceil(ne02/ngrp). For
tensors with ne03 > 1, all but the first ne00ne01ne02 elements were
left unwritten (exposed by the new GROUP_NORM test with
ne=[3,1,1,65537], num_groups=1).

Dispatch one threadgroup per (group, i03) pair (ngrp in x, ne03 in z,
same work distribution as the Vulkan backend) and compute per-batch
statistics, matching the CPU reference. Also clamp the group element
count for the last group when ne02 is not divisible by ngrp and use
int64_t indexing.

The kernel now only requires ggml_is_contiguous_rows(op->src[0])
instead of full contiguity: it addresses src0 and dst with their own
strides (nb03 and the dst strides are added to the kernel args - dst
can be a strided view of src0 with ggml_group_norm_inplace) and falls
back from the flat fast path to a strided path that decodes the linear
element index when rows or channels are padded. The flat/strided
selection is done on the host in
ggml_metal_library_get_pipeline_group_norm and compiled into one of
two specialized pipeline variants via a FC_group_norm_flat function
constant, so the dead path is eliminated at pipeline creation.
GROUP_NORM support is also gated on F32 src and dst in supports_op -
the kernel only implements f32 and an f16 input would silently be read
as f32.

Assisted-by: dsh:llama.cpp/ggml-org/GLM-5.3-Flash-GGUF (Mac Studio, M5 Ultra, 256GB)