Crate tcontract_exec 

Explicit execution contexts for the tcontract stack.

A host lends its Rayon pool through Pool::borrow; operations take an Exec. Work of width one runs on the calling thread and never touches the pool; wider work enters the pool once, and not at all when the caller is already one of its workers. See PERFORMANCE_TIPS.md, CPU Threading Contract.

Examples

use tcontract_exec::{Exec, Pool};
let tp = rayon::ThreadPoolBuilder::new().num_threads(2).build().unwrap();
let pool = Pool::borrow(&tp);
let exec = Exec::rayon(&pool);
let width = exec.install(2, |par| par.threads());
assert_eq!(width, 2);
assert_eq!(pool.stats().entries, 1);

Structs

ArenaProvider

A workspace owner: per-thread worker slots plus a free list of team sets.

Pool

A wrapper around a host’s borrowed, owned or shared Rayon pool.

PoolStats

Counters of how often a Pool was entered, for tests and benchmarks.

TeamLease

An exclusive loan of a team set, returned to its owner on drop.

WidthPolicy

Cost model for choosing a barrier-free partition width from the work.

WorkspaceReq

Bytes and counts one execute needs. Buffer sizes are bytes because the provider is element-type erased: the driver knows the element type and converts its real counts once.

WorkspaceStats

What an owner currently holds and currently lends out.

Enums

Exec

Execution context passed to every operation that may run in parallel.

ExecError

Errors from building or using an Exec.

Par

Parallelism granted to an operation by Exec::install.

Traits

WorkspaceProvider

Storage an execution may borrow. Implemented by the owner; the driver only ever sees this trait, so nothing here depends on the driver.