1# @ajax/mesh-rt-wasm
2
3The guest runtime of wasm CPU mesh programs, ported from alpha-rust-mesh's `crates/mesh-rt-wasm`: mesh-rt's
4surface (`mesh_ctx`, `mesh_view`, `mesh_exchange`, `MESH_PROGRAM(init, task)`) over the `mesh::*`
5imports of meshd's wasm executor. wasm32 only (`"targets": ["wasm32"]`).
6
7A program includes `mesh/rt_wasm.h`, writes `init` and `task`, and `MESH_PROGRAM(init, task)` exports
8`mesh_init`, `mesh_task` and `mesh_rt_abi`. A node is one CPU thread: `lane()` is 0 and `leader()` true.
9Views are windows reached through bounds-checked imports (use the bulk `read`/`write` in hot loops);
10linear memory is scratch. f32 in the cluster float mode is `@ajax/mesh-ftz`, whose operations on wasm32
11are the exported `mesh_ftz_*` helpers meshd's float guard allows.
12
13It also gives freestanding wasm32 code `memcpy`, `memmove`, `memset` and compiler-rt's `__multi3`.
14
15## Differences
16
17C has no OnceCell or slices: `mesh_ctx_get()` builds the context on first use, views are passed by value,
18and Option results are `bool` plus an out parameter.
19
20Tests: every guest in `programs/*-wasm`, through `@ajax/mesh-wasm-programs-check`.