Stabilize `asm_goto` feature gate
Stabilize `asm_goto` feature (tracked by #119364). The issue will remain open and be updated to track `asm_goto_with_outputs`.
Reference PR: https://github.com/rust-lang/reference/pull/1693
# Stabilization Report
This feature adds a `label <block>` operand type to `asm!`. `<block>` must be a block expression with type unit or never. The address of the block is substituted and the assembly may jump to the block. When block completes the `asm!` block returns and continues execution.
The block starts a new safety context and unsafe operations within must have additional `unsafe`s; the effect of `unsafe` that surrounds `asm!` block is cancelled. See https://github.com/rust-lang/rust/issues/119364#issuecomment-2316037703 and https://github.com/rust-lang/rust/pull/131544.
It's currently forbidden to use `asm_goto` with output operands; that is still unstable under `asm_goto_with_outputs`.
Example:
```rust
unsafe {
asm!(
"jmp {}",
label {
println!("Jumped from asm!");
}
);
}
```
Tests:
- tests/ui/asm/x86_64/goto.rs
- tests/ui/asm/x86_64/goto-block-safe.stderr
- tests/ui/asm/x86_64/bad-options.rs
- tests/codegen/asm/goto.rs
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