[Sushanth Rajasankar (sushraja-msft)]

Adds signed int8 and int64 support for Abs, Neg, Relu, and Sign to improve WebGPU EP coverage on WebNN WPT tests.

The measured WebNN WPT pass rate increased from 96.6% (1,691/1,751) to 97.1% (1,701/1,751) in combined validation. Eight newly passing integer unary cases correspond to this change; the other two gains are not attributed to this PR. The selection excludes float16 input/output cases.

Int64 unary kernels respect the enableInt64 opt-in; int8 support is unaffected.

Validation: all 12 native unary tests pass with no skips, covering enabled/disabled int64 configurations with CPU fallback disabled. WPT measurements predate the subsequent kernel refactor; WPT was not rerun afterward.

[Copilot]

🟡 Changes recommended

The new int64 Abs, Neg, Sign, and Relu kernels are registered even when enable_int64 is false, bypassing the documented opt-in and requiring guarded registration with enabled and disabled configuration coverage.

1 open issue

• Guard int64 kernel registrations behind enable_int64 · New

What changed in this PR

Adds signed int8 and int64 support for Abs, Neg, Relu, and Sign in ONNX Runtime’s WebGPU execution provider, expanding integer operator coverage for WebNN conformance.

Changes:

• Adds packed int8 handling and full-width, two-word int64 unary arithmetic.
• Registers the new int64 kernels across supported operator versions.
• Adds GPU-only integer tests and float32/int32 compatibility checks, including scalar, empty, and initializer inputs.

File	Description
onnxruntime/​test/​providers/​webgpu/​plugin/​unary_elementwise_ops_test.cc	Adds integer unary and compatibility tests with CPU fallback disabled.
onnxruntime/​core/​providers/​webgpu/​webgpu_execution_provider.cc	Adds versioned int64 unary kernel registrations.
onnxruntime/​core/​providers/​webgpu/​math/​unary_elementwise_ops.cc	Implements int8 unpacking and int64 unary shaders; extends supported types.

_{Review effort: Balanced}

[Copilot]

Note

Copilot was unable to run its full agentic suite in this review.

Copilot review overview

3 open issues

• The range described for i32 truncation is inaccurate/incomplete: truncation is lossy for values… · New
• This registration block is highly repetitive and error-prone to maintain (e.g., adding another… · New
• This new macro is introduced in this change but isn’t used anywhere in the shown diff. If it’s… · New

1 resolved since last review

• Guard int64 kernel registrations behind enable_int64

_{Review effort: Lite}

[Copilot]

🟢 Approval recommended

No active review issues are identified for the expanded WebGPU integer unary operator support.

No open issues 🎉

3 resolved since last review

• This registration block is highly repetitive and error-prone to maintain (e.g., adding another…
• The range described for i32 truncation is inaccurate/incomplete: truncation is lossy for values…
• This new macro is introduced in this change but isn’t used anywhere in the shown diff. If it’s…

_{Review effort: Balanced}