feat: add {stream,future}.forward canon builtins - #2614
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stream.forward canon builtinstream.splice canon builtin
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stream.splice canon builtinstream.{splice,forward} canon builtins
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stream.{splice,forward} canon builtins{stream,future}.forward canon builtins
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Implement parsing, validation, encoding, and printing support for the ⏩-gated `stream.forward` built-in proposed in WebAssembly/component-model#658: (canon stream.forward $streamT (core func $f)) where `$f` has type `(func (param i32 i32))`, taking a readable stream end and a writable stream end. `stream.forward` transfers both ends out of the calling instance and returns immediately with no result, so it takes neither an `n` parameter nor an `async` immediate. It also takes no `canonopt`s, since no elements pass through the caller's linear memory. The binary encoding uses opcode 0x2f as assigned in the proposed specification change, and validation gates the built-in behind the component model async and "more async builtins" features. Assisted-by: claude:claude-fable-5 Signed-off-by: Roman Volosatovs <rvolosatovs@riseup.net>
Implement parsing, validation, encoding, and printing support for the ⏩-gated `future.forward` built-in proposed in WebAssembly/component-model#658: (canon future.forward $futureT (core func $f)) where `$f` has type `(func (param i32 i32))`, taking a readable future end and a writable future end. Exactly like its `stream.forward` counterpart, `future.forward` transfers both ends out of the calling instance and returns immediately with no result, so it takes neither an `async` immediate nor any `canonopt`s, since the value does not pass through the caller's linear memory. The binary encoding uses opcode 0x2e as assigned in the proposed specification change, and validation gates the built-in behind the component model async and "more async builtins" features. Assisted-by: claude:claude-fable-5
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Pick up `wasmparser`/`wast`/`wasm-encoder` support for the `stream.forward` and `future.forward` canonical built-ins from bytecodealliance/wasm-tools#2614 until that lands upstream.
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Add support for
{stream,future}.forwardbuiltins as specified in WebAssembly/component-model#709