update stdarch submodule

[dgbo]

This commit update the src/stdarch submodule, we primarily want to include /~https://github.com/rust-lang/stdarch/pull/918 which provides prefetch hints for aarch64. This PR could deliver ~20% performance gain on our aarch64 server in Filecoin. Wish this could be used as soon as possible.

Thanks.

[rust-highfive]

Thanks for the pull request, and welcome! The Rust team is excited to review your changes, and you should hear from @kennytm (or someone else) soon.

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[rust-highfive]

⚠️ Warning ⚠️

• These commits modify submodules.

[kennytm]

This PR updates the stdarch dependency to the current master rust-lang/stdarch@7895ab1 (rust-lang/stdarch#917), but the CI at that commit is currently failing because const_fn_transmute is declared twice in /~https://github.com/rust-lang/stdarch/blob/master/crates/core_arch/src/lib.rs#L41.

error[E0636]: the feature `const_fn_transmute` has already been declared
  --> crates/core_arch/src/lib.rs:41:5
   |
41 |     const_fn_transmute
   |     ^^^^^^^^^^^^^^^^^^

error: aborting due to previous error

Please either change the commit to rust-lang/stdarch@b422b01 or remove the redundant const_fn_transmute feature.

[dgbo]

This PR updates the stdarch dependency to the current master rust-lang/stdarch@7895ab1 (rust-lang/stdarch#917), but the CI at that commit is currently failing because const_fn_transmute is declared twice in /~https://github.com/rust-lang/stdarch/blob/master/crates/core_arch/src/lib.rs#L41.

error[E0636]: the feature `const_fn_transmute` has already been declared
  --> crates/core_arch/src/lib.rs:41:5
   |
41 |     const_fn_transmute
   |     ^^^^^^^^^^^^^^^^^^

error: aborting due to previous error

Please either change the commit to rust-lang/stdarch@b422b01 or remove the redundant const_fn_transmute feature.

Thanks for the quick review. The commit is changed to rust-lang/stdarch@b422b01.

@rustbot modify labels: -S-waiting-on-author +S-waiting-on-review

[kennytm]

@bors r+ rollup=iffy

[bors]

📌 Commit 2e64ff9 has been approved by kennytm

[bors]

⌛ Testing commit 2e64ff9 with merge 1d216fe...

[bors]

☀️ Test successful - checks-actions, checks-azure
Approved by: kennytm
Pushing 1d216fe to master...