Intrinsic overflow checks perf trial

[pitaj]

Based on #128666

This PR exists to test the perf effects of adding a new intrinsic, like ub_checks, for overflow checks. Tests are expected to fail.

[rustbot]

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[rustbot]

Some changes occurred to the CTFE / Miri interpreter

cc @rust-lang/miri

Some changes occurred to MIR optimizations

cc @rust-lang/wg-mir-opt

This PR changes rustc_public

cc @oli-obk, @celinval, @ouz-a

Some changes occurred in compiler/rustc_codegen_cranelift

cc @bjorn3

Some changes occurred to constck

cc @fee1-dead

The Miri subtree was changed

cc @rust-lang/miri

Some changes occurred to the intrinsics. Make sure the CTFE / Miri interpreter
gets adapted for the changes, if necessary.

cc @rust-lang/miri, @RalfJung, @oli-obk, @lcnr

Some changes occurred to the CTFE machinery

cc @RalfJung, @oli-obk, @lcnr

Some changes occurred in compiler/rustc_codegen_ssa

cc @WaffleLapkin

Some changes occurred in src/tools/clippy

cc @rust-lang/clippy

This PR changes MIR

cc @oli-obk, @RalfJung, @JakobDegen, @vakaras

[bors]

☔ The latest upstream changes (presumably #146683) made this pull request unmergeable. Please resolve the merge conflicts.

[rustbot]

This PR was rebased onto a different master commit. Here's a range-diff highlighting what actually changed.

Rebasing is a normal part of keeping PRs up to date, so no action is needed—this note is just to help reviewers.