This commit refactors the Wasmtime CLI tools to use `structopt` instead of `docopt`. The `wasmtime` tool now has the following subcommands: * `config new` - creates a new Wasmtime configuration file. * `run` - runs a WebAssembly module. * `wasm2obj` - translates a Wasm module to native object file. * `wast` - runs a test script file. If no subcommand is specified, the `run` subcommand is used. Thus, `wasmtime foo.wasm` should continue to function as expected. The `wasm2obj` and `wast` tools still exist, but delegate to the same implementation as the `wasmtime` subcommands. The standalone `wasm2obj` and `wast` tools may be removed in the future in favor of simply using `wasmtime`. Included in this commit is a breaking change to the default Wasmtime configuration file: it has been renamed from `wasmtime-cache-config.toml` to simply `config.toml`. The new name is less specific which will allow for additional (non-cache-related) settings in the future. There are some breaking changes to improve command line UX: * The `--cache-config` option has been renamed to `--config`. * The `--create-config-file` option has moved to the `config new` subcommand. As a result, the `wasm2obj` and `wast` tools cannot be used to create a new config file. * The short form of the `--optimize` option has changed from `-o` to `-O` for consistency. * The `wasm2obj` command takes the output object file as a required positional argument rather than the former required output *option* (e.g. `wasmtime wasm2obj foo.wasm foo.obj`).
This is the wasmtime-environ crate, which contains the implementations
of the ModuleEnvironment and FuncEnvironment traits from
cranelift-wasm. They effectively
implement an ABI for basic wasm compilation that defines how linear memories
are allocated, how indirect calls work, and other details. They can be used
for JITing, native object files, or other purposes.