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vulkan: fix wrong results when a mul_mat reads a slice of a larger cache (#28956)

  • vulkan: read the batch stride of an in place src0 from nb[2]

A dim01 contiguous tensor can still be a view whose batches are
strided by more than ne[1] rows, the first rows of a KV cache for
example. Both the mat-vec and the matrix paths read such a tensor in
place but passed ne00*ne01 as the batch stride, so every head past
the first read the wrong rows. The same applies to src1. The stride
now comes from nb[2] whenever the tensor is used in place; the value
is unchanged for a contiguous tensor.

test-backend-ops gets an m_v parameter on test_mul_mat, the number of
rows of a in memory, and two cases at the shapes of a decoder self
attention over a cache.

  • vulkan: size the in place A and B ranges by their strided extent

The matrix path bound src0 and src1 to the shader with a range of
elements times type size, which ends before the batches of a strided
view. Pipelines with bounded access read zero past that range, so the
same view that the mat-vec path already handles gave wrong results
on Intel and on NVIDIA without coopmat2. The range now comes from
ggml_nbytes when the tensor is read in place.

  • vulkan: address review from jeffbolznv

Bind the in place A and B of the matrix path with ggml_vk_subbuffer,
which spans to the end of the buffer, so a strided view is in range
without computing its extent.

mul_mat_id reads the batch stride of an in place src0 and src1 with
the same helper as mul_mat. test_mul_mat_id gets an m_v parameter,
the number of rows of as in memory, and a case whose experts are
strided by more rows than it uses.

  • vulkan: read the batch stride of an in place src0 in mul_mat_vec_id

The single token path of mul_mat_id passed ne00*ne01 as the batch
stride of A, so a strided expert view read the wrong rows. The stride
now comes from ggml_vk_batch_stride like the other three paths, and
src1 follows the same rule.

test_mul_mat_id gets a single token case over the strided view.

  • vulkan: address review from jeffbolznv

The batch stride of an in place tensor is taken from nb[2] as
nb[2] / type_size * block_size, which holds when nb[2] is padded and
not a multiple of nb[1]. A test_mul_mat case with a padded batch stride
covers it.

  • vulkan: keep the A and B ranges exact in mul_mm

The quantized A loads of mul_mm carry no row bound and rely on the
descriptor range to read zeros past the last row of a partial tile.
Binding A and B up to the end of the buffer let those tiles read the
leftovers of a previous node and hung the NVFP4 mul_mm on NVIDIA
without coopmat2. The range is the strided extent of a tensor read in
place and the staged size otherwise.

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openEuler:

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

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