async/stream/future plumbing for wasmtime-environ

I've split this out of bytecodealliance#9582 to make review easier.

This patch includes the plumbing needed to route
async/stream/future/error-context data from `wit-parser`, through the various
layers of `wasmtime-environ`, and on to `wasmtime-cranelift` and `wasmtime`.
The `wasmtime::runtime`, `wasmtime_environ::fact`, and
`wasmtime_cranelift::compiler::component` modules only contain `todo!()` stubs
to begin with; I'll flesh those out in later PRs.

Signed-off-by: Joel Dice <[email protected]>

remove debugging code

Signed-off-by: Joel Dice <[email protected]>

revert comment formatting change in trap_encoding.rs

Signed-off-by: Joel Dice <[email protected]>

deduplicate code in inline.rs

Signed-off-by: Joel Dice <[email protected]>

remove `ComponentTypesBuilder::error_context_type`

This was just an alias for `error_context_table_type`, which I've made public.

Signed-off-by: Joel Dice <[email protected]>

defer `VMComponentOffsets` changes to a future PR

Signed-off-by: Joel Dice <[email protected]>

Author: dicej

crates/cranelift/src/compiler/component.rs

@@ -94,6 +94,103 @@ impl<'a> TrampolineCompiler<'a> {
             Trampoline::AlwaysTrap => {
                 self.translate_always_trap();
             }
+            Trampoline::TaskBackpressure { instance } => {
+                _ = instance;
+                todo!()
+            }
+            Trampoline::TaskReturn => todo!(),
+            Trampoline::TaskWait {
+                instance,
+                async_,
+                memory,
+            } => {
+                _ = (instance, async_, memory);
+                todo!()
+            }
+            Trampoline::TaskPoll {
+                instance,
+                async_,
+                memory,
+            } => {
+                _ = (instance, async_, memory);
+                todo!()
+            }
+            Trampoline::TaskYield { async_ } => {
+                _ = async_;
+                todo!()
+            }
+            Trampoline::SubtaskDrop { instance } => {
+                _ = instance;
+                todo!()
+            }
+            Trampoline::StreamNew { ty } => {
+                _ = ty;
+                todo!()
+            }
+            Trampoline::StreamRead { ty, options } => {
+                _ = (ty, options);
+                todo!()
+            }
+            Trampoline::StreamWrite { ty, options } => {
+                _ = (ty, options);
+                todo!()
+            }
+            Trampoline::StreamCancelRead { ty, async_ } => {
+                _ = (ty, async_);
+                todo!()
+            }
+            Trampoline::StreamCancelWrite { ty, async_ } => {
+                _ = (ty, async_);
+                todo!()
+            }
+            Trampoline::StreamCloseReadable { ty } => {
+                _ = ty;
+                todo!()
+            }
+            Trampoline::StreamCloseWritable { ty } => {
+                _ = ty;
+                todo!()
+            }
+            Trampoline::FutureNew { ty } => {
+                _ = ty;
+                todo!()
+            }
+            Trampoline::FutureRead { ty, options } => {
+                _ = (ty, options);
+                todo!()
+            }
+            Trampoline::FutureWrite { ty, options } => {
+                _ = (ty, options);
+                todo!()
+            }
+            Trampoline::FutureCancelRead { ty, async_ } => {
+                _ = (ty, async_);
+                todo!()
+            }
+            Trampoline::FutureCancelWrite { ty, async_ } => {
+                _ = (ty, async_);
+                todo!()
+            }
+            Trampoline::FutureCloseReadable { ty } => {
+                _ = ty;
+                todo!()
+            }
+            Trampoline::FutureCloseWritable { ty } => {
+                _ = ty;
+                todo!()
+            }
+            Trampoline::ErrorContextNew { ty, options } => {
+                _ = (ty, options);
+                todo!()
+            }
+            Trampoline::ErrorContextDebugMessage { ty, options } => {
+                _ = (ty, options);
+                todo!()
+            }
+            Trampoline::ErrorContextDrop { ty } => {
+                _ = ty;
+                todo!()
+            }
             Trampoline::ResourceNew(ty) => self.translate_resource_new(*ty),
             Trampoline::ResourceRep(ty) => self.translate_resource_rep(*ty),
             Trampoline::ResourceDrop(ty) => self.translate_resource_drop(*ty),
@@ -115,6 +212,26 @@ impl<'a> TrampolineCompiler<'a> {
                     me.raise_if_host_trapped(rets.pop().unwrap());
                 })
             }
+            Trampoline::AsyncEnterCall => todo!(),
+            Trampoline::AsyncExitCall {
+                callback,
+                post_return,
+            } => {
+                _ = (callback, post_return);
+                todo!()
+            }
+            Trampoline::FutureTransfer => {
+                _ = host::future_transfer;
+                todo!()
+            }
+            Trampoline::StreamTransfer => {
+                _ = host::stream_transfer;
+                todo!()
+            }
+            Trampoline::ErrorContextTransfer => {
+                _ = host::error_context_transfer;
+                todo!()
+            }
         }
     }
 
@@ -159,8 +276,14 @@ impl<'a> TrampolineCompiler<'a> {
             realloc,
             post_return,
             string_encoding,
+            callback: _,
+            async_,
         } = *options;
 
+        if async_ {
+            todo!()
+        }
+
         // vmctx: *mut VMComponentContext
         host_sig.params.push(ir::AbiParam::new(pointer_type));
         callee_args.push(vmctx);

crates/environ/examples/factc.rs

@@ -147,6 +147,8 @@ impl Factc {
                     realloc: Some(dummy_def()),
                     // Lowering never allows `post-return`
                     post_return: None,
+                    async_: false,
+                    callback: None,
                 },
                 lift_options: AdapterOptions {
                     instance: RuntimeComponentInstanceIndex::from_u32(1),
@@ -159,6 +161,8 @@ impl Factc {
                     } else {
                         None
                     },
+                    async_: false,
+                    callback: None,
                 },
                 func: dummy_def(),
             });

crates/environ/src/component.rs

@@ -83,6 +83,10 @@ macro_rules! foreach_builtin_component_function {
             resource_enter_call(vmctx: vmctx);
             resource_exit_call(vmctx: vmctx) -> bool;
 
+            future_transfer(vmctx: vmctx, src_idx: u32, src_table: u32, dst_table: u32) -> u64;
+            stream_transfer(vmctx: vmctx, src_idx: u32, src_table: u32, dst_table: u32) -> u64;
+            error_context_transfer(vmctx: vmctx, src_idx: u32, src_table: u32, dst_table: u32) -> u64;
+
             trap(vmctx: vmctx, code: u8);
 
             utf8_to_utf8(src: ptr_u8, len: size, dst: ptr_u8) -> bool;