Koute
e349fc9ef8
This PR adds initial support for building RISC-V runtimes targeting PolkaVM. - Setting the `SUBSTRATE_RUNTIME_TARGET=riscv` environment variable will now build a RISC-V runtime instead of a WASM runtime. - This only adds support for *building* runtimes; running them will need a PolkaVM-based executor, which I will add in a future PR. - Only building the minimal runtime is supported (building the Polkadot runtime doesn't work *yet* due to one of the dependencies). - The builder now sets a `substrate_runtime` cfg flag when building the runtimes, with the idea being that instead of doing `#[cfg(not(feature = "std"))]` or `#[cfg(target_arch = "wasm32")]` to detect that we're building a runtime you'll do `#[cfg(substrate_runtime)]`. (Switching the whole codebase to use this will be done in a future PR; I deliberately didn't do this here to keep this PR minimal and reviewable.) - Further renaming of things (e.g. types, environment variables and proc macro attributes having "wasm" in their name) to be target-agnostic will also be done in a future refactoring PR (while keeping backwards compatibility where it makes sense; I don't intend to break anyone's workflow or create unnecessary churn). - This PR also fixes two bugs in the `wasm-builder` crate: * The `RUSTC` environment variable is now removed when invoking the compiler. This prevents the toolchain version from being overridden when called from a `build.rs` script. * When parsing the `rustup toolchain list` output the `(default)` is now properly stripped and not treated as part of the version. - I've also added a minimal CI job that makes sure this doesn't break in the future. (cc @paritytech/ci) cc @athei ------ Also, just a fun little tidbit: quickly comparing the size of the built runtimes it seems that the PolkaVM runtime is slightly smaller than the WASM one. (`production` build, with the `names` section substracted from the WASM's size to keep things fair, since for the PolkaVM runtime we're currently stripping out everything) - `.wasm`: 625505 bytes - `.wasm` (after wasm-opt -O3): 563205 bytes - `.wasm` (after wasm-opt -Os): 562987 bytes - `.wasm` (after wasm-opt -Oz): 536852 bytes - `.polkavm`: ~~580338 bytes~~ 550476 bytes (after enabling extra target features; I'll add those in another PR once we have an executor working) --------- Co-authored-by: Bastian Köcher <git@kchr.de>
Substrate runtime api
The Substrate runtime api is the crucial interface between the node and the runtime.
Every call that goes into the runtime is done with a runtime api. The runtime apis are not fixed.
Every Substrate user can define its own apis with
decl_runtime_apis and implement them in
the runtime with impl_runtime_apis.
Every Substrate runtime needs to implement the [Core] runtime api. This api provides the basic
functionality that every runtime needs to export.
Besides the macros and the [Core] runtime api, this crates provides the [Metadata] runtime
api, the [ApiExt] trait, the [CallApiAt] trait and the [ConstructRuntimeApi] trait.
On a meta level this implies, the client calls the generated API from the client perspective.
License: Apache-2.0