Stack from [ghstack](https://github.com/ezyang/ghstack/tree/0.15.0)
(oldest at bottom):
* #20465
* #20464
* #20463
* #20435
* #20399
* #20398
* #20397
* #20396
* #20395
* #20394
* #20393
* #20392
* #20391
* #20390
* #20363
* __->__ #20362
* #20361
* #20360
* #20359



Adds `aten.select_copy.int` to the WebGPU delegate as a gather: picks a
fixed index along one dim, producing an output of rank (input rank - 1).

Composition (single dispatch):
- `select/Select.cpp` — reads `[self, dim, index, out]` (static `Int`
via `read_scalar`; throws on dynamic `SymInt`), normalizes +
bounds-checks dim/index, builds 2 `TensorMeta` UBOs + a
`SelectParams{dim,index}`, fp32 guard, 1D-dispatch over `numel`,
releases uniforms after the bind group.
- `select/select.wgsl` — seeds the input offset with `index *
in.strides[dim]`, delinearizes the output index, maps each out dim to
its in dim (shifted past the selected dim), relinearizes on input
strides.
@exported-using-ghexport

Differential Revision:
[D108793166](https://our.internmc.facebook.com/intern/diff/D108793166/)

Differential Revision:
[D108793166](https://our.internmc.facebook.com/intern/diff/D108793166)

…ework) (#20363)

Stack from [ghstack](https://github.com/ezyang/ghstack/tree/0.15.0)
(oldest at bottom):
* #20465
* #20464
* #20463
* #20435
* #20399
* #20398
* #20397
* #20396
* #20395
* #20394
* #20393
* #20392
* #20391
* #20390
* __->__ #20363
* #20362
* #20361
* #20360
* #20359



Registers `aten.select_copy.int` in the `cases.py` op-test framework: a
`_select_suite` of 4 configs (leading/middle/last dim + negative index)
that `generate_op_tests` exports and compares to a torch golden on Dawn.
Also adds `test/ops/select/test_select.py` (`SelectModule` + `CONFIGS` +
an export-delegation/eager smoke test) and the `aten.select_copy.int`
partitioner-allowlist entry in `tester.py`.
@exported-using-ghexport

Differential Revision:
[D108793161](https://our.internmc.facebook.com/intern/diff/D108793161/)

Differential Revision:
[D108793161](https://our.internmc.facebook.com/intern/diff/D108793161)

Stack from [ghstack](https://github.com/ezyang/ghstack/tree/0.15.0)
(oldest at bottom):
* #20465
* #20464
* #20463
* #20435
* #20399
* #20398
* #20397
* #20396
* #20395
* #20394
* #20393
* #20392
* #20391
* __->__ #20390
* #20363
* #20362
* #20361
* #20360
* #20359



Adds `aten.sigmoid.default` to the WebGPU delegate: element-wise
`1/(1+exp(-x))` over a flat fp32 buffer. On the Llama critical path
(`F.silu` -> `sigmoid` + `mul`).

Composition (single dispatch):
- `sigmoid/UnaryOp.cpp` — binds input (storage, read-only) + output
(storage) + a `Params{num_elements}` uniform, 1D-dispatches over
`num_elements` with `override wg_size` (clamped to the device limit);
mirrors the `add` op (uniform mapped-at-creation, released after the
bind group).
- `sigmoid/sigmoid.wgsl` — guards `idx >= num_elements` and writes the
logistic of each element.
@exported-using-ghexport

Differential Revision:
[D108793157](https://our.internmc.facebook.com/intern/diff/D108793157/)

Differential Revision:
[D108793157](https://our.internmc.facebook.com/intern/diff/D108793157)

…k) (#20391)

Stack from [ghstack](https://github.com/ezyang/ghstack/tree/0.15.0)
(oldest at bottom):
* #20465
* #20464
* #20463
* #20435
* #20399
* #20398
* #20397
* #20396
* #20395
* #20394
* #20393
* #20392
* __->__ #20391
* #20390
* #20363
* #20362
* #20361
* #20360
* #20359



Registers `aten.sigmoid.default` in the `cases.py` op-test framework: a
`_sigmoid_suite` (hard-coded shapes + a saturation case over a
`linspace(-12, 12)` input) that `generate_op_tests` exports and compares
to an fp64 torch golden on Dawn. Also adds
`test/ops/sigmoid/test_sigmoid.py` (`SigmoidModule` + `N` + `_det_input`
+ an export-delegation/eager smoke test) and the `aten.sigmoid.default`
partitioner-allowlist entry in `tester.py`.
@exported-using-ghexport

Differential Revision:
[D108793159](https://our.internmc.facebook.com/intern/diff/D108793159/)

Differential Revision:
[D108793159](https://our.internmc.facebook.com/intern/diff/D108793159)

…20392)

Stack from [ghstack](https://github.com/ezyang/ghstack/tree/0.15.0)
(oldest at bottom):
* #20465
* #20464
* #20463
* #20435
* #20399
* #20398
* #20397
* #20396
* #20395
* #20394
* #20393
* __->__ #20392
* #20391
* #20390
* #20363
* #20362
* #20361
* #20360
* #20359



Adds `aten.squeeze_copy.dims` and `aten.unsqueeze_copy.default` to the
WebGPU delegate. Both are numel-preserving shape ops; on a dense
row-major buffer backend they are the same flat copy as `view_copy` —
only the shape metadata differs (mirrors the Vulkan delegate, which
routes both through `add_view_copy_node`).

Composition (no new kernel):
- `squeeze/Squeeze.cpp` — reads `args = [self, dims, out]`, ignores the
AOT-fixed `dims`, calls `add_flat_copy(graph, in, out)` from
`runtime/ops/view_copy/view_copy.h`.
- `unsqueeze/Unsqueeze.cpp` — reads `args = [self, dim, out]`, ignores
the AOT-fixed `dim`, calls `add_flat_copy(graph, in, out)`.
@exported-using-ghexport

Differential Revision:
[D108793153](https://our.internmc.facebook.com/intern/diff/D108793153/)

Differential Revision:
[D108793153](https://our.internmc.facebook.com/intern/diff/D108793153)

….py op-test framework) (#20393)

Stack from [ghstack](https://github.com/ezyang/ghstack/tree/0.15.0)
(oldest at bottom):
* #20465
* #20464
* #20463
* #20435
* #20399
* #20398
* #20397
* #20396
* #20395
* #20394
* __->__ #20393
* #20392
* #20391
* #20390
* #20363
* #20362
* #20361
* #20360
* #20359



Registers `aten.squeeze_copy.dims` and `aten.unsqueeze_copy.default` in
the `cases.py` op-test framework: a `_squeeze_suite` of 3 configs
(squeeze leading/middle/multiple size-1 dims) and a `_unsqueeze_suite`
of 3 configs (insert dim at front/middle/last) that `generate_op_tests`
exports via `VulkanPartitioner` and compares to a torch golden on Dawn.
Also adds `test/ops/squeeze/test_squeeze.py` (`SqueezeModule` +
`CONFIGS` + `_op_delegated` smoke test),
`test/ops/unsqueeze/test_unsqueeze.py` (`UnsqueezeModule` + `CONFIGS` +
`_op_delegated` smoke test), and the two partitioner-allowlist entries
in `tester.py`.
@exported-using-ghexport

Differential Revision:
[D108793152](https://our.internmc.facebook.com/intern/diff/D108793152/)

Differential Revision:
[D108793152](https://our.internmc.facebook.com/intern/diff/D108793152)

Pull Request resolved: #20360

**Add `aten.view_copy.default` as a native buffer-to-buffer DMA** — a contiguous reshape on the dense row-major buffer backend is a flat copy, so it needs no shader.

**Problem:** a reshape only relabels shape metadata; the bytes are unchanged. Launching a compute dispatch (shader module + pipeline + bind group + uniform) just to run `output[i] = input[i]` is wasted setup for every view/clone/squeeze/unsqueeze in the graph.

**Solution:**
- Before: a `view_copy.wgsl` compute kernel dispatched over `num_elements`, with its own pipeline/bind-group/uniform per copy.
- After: `add_flat_copy` records a `wgpuCommandEncoderCopyBufferToBuffer` DMA in graph order — no shader, no pipeline, no uniform.

**Implementation:**
- `WebGPUGraph` gains a `WebGPUDispatch::Kind::Copy` command + `add_buffer_copy(src, dst, nbytes)`; `execute()` emits the encoder-level copy between compute passes (both single-shot and chunked paths), preserving the existing per-pass read-after-write ordering.
- `add_flat_copy` (declared in `view_copy.h`, reused by the stacked clone/squeeze/unsqueeze) keeps the fail-loud guards (both tensors, fp32 4-byte alignment, equal `nbytes`) and treats an aliased in/out buffer as a no-op.
- Tensor buffers already carry `CopySrc | CopyDst`, so no usage-flag change is needed.
- Mirrors Vulkan `add_view_copy_node` (`backends/vulkan/runtime/graph/ops/impl/View.cpp`): Vulkan always dispatches `view_buffer.glsl` only to remap non-contiguous layouts, which the buffer-only WebGPU backend never produces — so the contiguous DMA is the equivalent path.
ghstack-source-id: 397026498
@exported-using-ghexport

Differential Revision: [D108793164](https://our.internmc.facebook.com/intern/diff/D108793164/)

Stack from [ghstack](https://github.com/ezyang/ghstack/tree/0.15.0)
(oldest at bottom):
* #20465
* #20464
* #20463
* #20435
* #20399
* #20398
* #20397
* #20396
* #20395
* __->__ #20394
* #20393
* #20392
* #20391
* #20390
* #20363
* #20362
* #20361
* #20360
* #20359



Adds `aten.slice_copy.Tensor` to the WebGPU delegate as a gather: each
output element is mapped back to its source input element along the
sliced dim via `start + coord * step`.

Composition (single compute dispatch):
- `runtime/ops/slice/Slice.cpp` — reads `args = [self, dim, start, end,
step, out]` via `read_scalar` (static `Int`/`Null`-sentinel default;
throws on dynamic `SymInt`); normalizes negative `dim`/`start`, clamps
`start` to `[0, in_size]`; builds two `TensorMeta` UBOs + a
`SliceParams{dim, start, step}` uniform; guards fp32; dispatches over
`compute_1d_workgroup_count(out.numel)` with `override wg_size`;
releases all uniforms after the bind group.
- `runtime/ops/slice/slice.wgsl` — delinearizes the output index over
the contiguous output strides, maps the sliced-dim coordinate back to
the input (`start + coord*step`), relinearizes over the input strides.
@exported-using-ghexport

Differential Revision:
[D108793168](https://our.internmc.facebook.com/intern/diff/D108793168/)

Differential Revision:
[D108793168](https://our.internmc.facebook.com/intern/diff/D108793168)

…work) (#20395)

Stack from [ghstack](https://github.com/ezyang/ghstack/tree/0.15.0)
(oldest at bottom):
* #20465
* #20464
* #20463
* #20435
* #20399
* #20398
* #20397
* #20396
* __->__ #20395
* #20394
* #20393
* #20392
* #20391
* #20390
* #20363
* #20362
* #20361
* #20360
* #20359



Registers `aten.slice_copy.Tensor` in the `cases.py` op-test framework:
a `_slice_suite` of 4 configs (leading-dim slice `[:,1:5]`, last-dim
slice `[...,1:3]`, step-2 `[:,0:8:2]`, negative-end `[:,1:-1]`) that
`generate_op_tests` exports via `VulkanPartitioner` and compares to a
torch golden on Dawn. Also adds `test/ops/slice/test_slice.py`
(`SliceModule` + `CONFIGS` + export-delegation/eager smoke test) and the
`aten.slice_copy.Tensor` partitioner-allowlist entry in `tester.py`.
@exported-using-ghexport

Differential Revision:
[D108793151](https://our.internmc.facebook.com/intern/diff/D108793151/)

Differential Revision:
[D108793151](https://our.internmc.facebook.com/intern/diff/D108793151)

…ermute_copy.default) (#20396)

Stack from [ghstack](https://github.com/ezyang/ghstack/tree/0.15.0)
(oldest at bottom):
* #20465
* #20464
* #20463
* #20435
* #20399
* #20398
* #20397
* __->__ #20396
* #20395
* #20394
* #20393
* #20392
* #20391
* #20390
* #20363
* #20362
* #20361
* #20360
* #20359



Adds `aten.permute_copy.default` (a coordinate-reorder gather) to the
WebGPU delegate, and the `IntList` graph value type it needs to read its
`dims` argument.

Composition:
- `runtime/WebGPUGraph.{h,cpp}` — adds `ValueType::IntList` backed by
`std::vector<std::vector<int64_t>> int_lists_` + `get_int_list(int)`;
`build()` deserializes `vkgraph::GraphTypes::IntList` via
`value_as_IntList()->items()` (int64, matching the FlatBuffer `[long]`);
mirrors the existing scalar value plumbing.
- `runtime/ops/permute/Permute.cpp` — reads the permutation via
`get_int_list`, normalizes negative dims, validates it is a permutation
of `[0, ndim)`, builds two `TensorMeta` UBOs + a `PermuteParams{perm:
vec4<u32>}` uniform, guards fp32 + rank≤4, dispatches over
`compute_1d_workgroup_count(out.numel)` with `override wg_size`;
releases all uniforms after the bind group.
- `runtime/ops/permute/permute.wgsl` — delinearizes the output index
over the contiguous output strides, reads `input` at
`in.strides[perm[d]]` per dim (mirrors Vulkan `permute_buffer.glsl`).
- Registers both `aten.permute_copy.default` and `aten.permute.default`
to the same handler.
@exported-using-ghexport

Differential Revision:
[D108793162](https://our.internmc.facebook.com/intern/diff/D108793162/)

Differential Revision:
[D108793162](https://our.internmc.facebook.com/intern/diff/D108793162)

…mework) (#20397)

Stack from [ghstack](https://github.com/ezyang/ghstack/tree/0.15.0)
(oldest at bottom):
* #20465
* #20464
* #20463
* #20435
* #20399
* #20398
* __->__ #20397
* #20396
* #20395
* #20394
* #20393
* #20392
* #20391
* #20390
* #20363
* #20362
* #20361
* #20360
* #20359



Registers `aten.permute_copy.default` in the `cases.py` op-test
framework: a `_permute_suite` of 4 configs (3D rotation, 4D middle-dim
transpose, 2D transpose, full 4D shuffle) that `generate_op_tests`
exports via `VulkanPartitioner` and compares to a torch golden on Dawn.
Also adds `test/ops/permute/test_permute.py` (`PermuteModule` +
`CONFIGS` + `_op_delegated` smoke test) and the
`aten.permute_copy.default` partitioner-allowlist entry in `tester.py`.
@exported-using-ghexport

Differential Revision:
[D108793156](https://our.internmc.facebook.com/intern/diff/D108793156/)

Differential Revision:
[D108793156](https://our.internmc.facebook.com/intern/diff/D108793156)