This commit introduces initial support for multi-value Wasm. Wasm blocks and
calls can now take and return an arbitrary number of values.
The encoding for multi-value blocks means that we need to keep the contents of
the "Types" section around when translating function bodies. To do this, we
introduce a `WasmTypesMap` type that maps the type indices to their parameters
and returns, construct it when parsing the "Types" section, and shepherd it
through a bunch of functions and methods when translating function bodies.
`VisibleTranslationState` was a wrapper around a `TranslationState` that was
meant to public API consumers outside of this crate. However, the internal
`TranslationState` and all its methods were still publicly exposed! This commit
simplifies and remedies the situation by combining them into a single
`TranslationState` type. Most of its methods are only `pub(crate)` now, not
visible to the entire world. The only methods that are `pub` are the ones that
`VisibleTranslationState` exposed.
This commit adds a hook to the `ModuleEnvironment` trait to learn when a
custom section in a wasm file is read. This hook can in theory be used
to parse and handle custom sections as they appear in the wasm file
without having to re-iterate over the wasm file after cranelift has
already parsed the wasm file.
The `translate_module` function is now less strict in that it doesn't
require sections to be in a particular order, but it's figured that the
wasm file is already validated elsewhere to verify the section order.
-Add resumable_trap, safepoint, isnull, and null instructions
-Add Stackmap struct and StackmapSink trait
Co-authored-by: Mir Ahmed <mirahmed753@gmail.com>
Co-authored-by: Dan Gohman <sunfish@mozilla.com>
* [wasm] return a WasmResult from `declare_table_elements`
This method in particular needs to accommodate failure because any table index other than zero is
currently invalid.
* [wasm] additional failure handling improvements
- Adds `WasmResult<()>` as the return type for most of the `ModuleEnvironment` methods that
previously returned nothing.
- Replaces some panics with `WasmError::Unsupported` now that the methods can return a result.
- Adds a `wasm_unsupported!()` macro for early returns with a formatted unsupported message.
