Module hint 

Branch-prediction hints for hot handlers.

Both functions are identity over bool on every supported target. The call site cost is zero: the compiler inlines them into the containing branch with no runtime effect. What they communicate is intent. A handler that expects the fast path to win 99% of the time writes

if hopper::utils::hint::likely(is_cached) {
    return fast_path(ctx);
}
slow_path(ctx)

and the compiler keeps the fast path straight-line, pushing the spill into the cold branch. Same story for [unlikely] in the opposite direction.

On host targets (tests, off-chain tooling) future versions may route through core::intrinsics::likely when that intrinsic is stabilized; the API shape stays identical so user code never needs to change. On SBF the Solana runtime does not expose a branch-weight hint today, so the hint compiles out entirely. Leaving the calls in the code path is safe and free.

Functions

likely

Hint the branch condition is probably true. Zero runtime cost on SBF; on host targets it maps to LLVM’s llvm.expect.i1 via core::hint::likely when available, and to an identity otherwise.

unlikely

Hint the branch condition is probably false. Mirror of likely.