[torch.compile] Enable silu_mul_fp8_quant fusion without custom ops enabled

[ZJY0516]

Purpose

Based on #24604, modified activation fusion pass to do op matching w/o needing to enable the custom op.

Test Plan

pytest -s tests/compile/test_silu_mul_quant_fusion.py

Test Result

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• The purpose of the PR, such as "Fix some issue (link existing issues this PR will resolve)".
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[gemini-code-assist]

Code Review

This pull request enables the silu_mul_fp8_quant fusion pass to work even when the silu_and_mul custom operator is not enabled, by matching against the native PyTorch implementation. This is achieved by introducing a MatcherSiluAndMul utility that can trace either the custom op or the native implementation. The changes are well-structured and the tests have been updated to cover both scenarios. My review found a minor issue in the test suite where TestSiluMulNvfp4QuantModel is not correctly handled by the new test parameterization, which would cause test failures. I've provided a suggestion to fix this by adding appropriate skip conditions.

[ProExpertProg]

Looks great! For tests, could you only generate relevant tests, and then skip based on support (right now it's a little bit mixed up)

[ProExpertProg]

Great work! Could you post some E2E perf and accuracy numbers? And would you be interested in adding dynamic quant support as a follow-up?

[ZJY0516]

Great work! Could you post some E2E perf and accuracy numbers?

Do you know which model use silu_mul and fp8 quant?

And would you be interested in adding dynamic quant support as a follow-up?

Sure.

[ProExpertProg]

Do you know which model use silu_mul and fp8 quant?

silu_mul is used by basically all models. fp8 quant is used by the -FP8 quantized models. For example you can use redhatai/meta-llama3.1-8b-instruct-fp8 or redhatai/meta-llama3.1-70B-instruct-fp8