Remove backpressure.set (#2397)

* Remove `backpressure.set`

The replacements of `backpressure.{inc,dec}` have been around for
awhile, no need to keep these any more.

* Fix wit-dylib tests

Author: alexcrichton

Cargo.lock

@@ -478,12 +478,6 @@ impl ComponentBuilder {
         self.core_funcs.add(Some("thread.available-parallelism"))
     }
 
-    /// Declares a new `backpressure.set` intrinsic.
-    pub fn backpressure_set(&mut self) -> u32 {
-        self.canonical_functions().backpressure_set();
-        self.core_funcs.add(Some("backpressure.set"))
-    }
-
     /// Declares a new `backpressure.inc` intrinsic.
     pub fn backpressure_inc(&mut self) -> u32 {
         self.canonical_functions().backpressure_inc();

crates/wasm-encoder/src/component/builder.rs

@@ -196,16 +196,6 @@ impl CanonicalFunctionSection {
         self
     }
 
-    /// Defines a function which tells the host to enable or disable
-    /// backpressure for the caller's instance.  When backpressure is enabled,
-    /// the host must not start any new calls to that instance until
-    /// backpressure is disabled.
-    pub fn backpressure_set(&mut self) -> &mut Self {
-        self.bytes.push(0x08);
-        self.num_added += 1;
-        self
-    }
-
     /// Defines a function which tells the host to increment the backpressure
     /// counter.
     pub fn backpressure_inc(&mut self) -> &mut Self {

crates/wasm-encoder/src/component/canonicals.rs

@@ -977,9 +977,6 @@ pub mod component_utils {
             wasmparser::CanonicalFunction::ThreadAvailableParallelism => {
                 section.thread_available_parallelism();
             }
-            wasmparser::CanonicalFunction::BackpressureSet => {
-                section.backpressure_set();
-            }
             wasmparser::CanonicalFunction::BackpressureInc => {
                 section.backpressure_inc();
             }

crates/wasm-encoder/src/reencode/component.rs

@@ -90,9 +90,6 @@ pub enum CanonicalFunction {
     /// A function which returns the number of threads that can be expected to
     /// execute concurrently
     ThreadAvailableParallelism,
-    /// A function which tells the host to enable or disable backpressure for
-    /// the caller's instance.
-    BackpressureSet,
     /// A function which tells the host to enable backpressure by incrementing
     /// the component's counter by 1.
     BackpressureInc,
@@ -329,7 +326,6 @@ impl<'a> FromReader<'a> for CanonicalFunction {
             0x04 => CanonicalFunction::ResourceRep {
                 resource: reader.read()?,
             },
-            0x08 => CanonicalFunction::BackpressureSet,
             0x24 => CanonicalFunction::BackpressureInc,
             0x25 => CanonicalFunction::BackpressureDec,
             0x09 => CanonicalFunction::TaskReturn {

crates/wasmparser/src/readers/component/canonicals.rs

@@ -1185,7 +1185,6 @@ impl ComponentState {
             CanonicalFunction::ThreadAvailableParallelism => {
                 self.thread_available_parallelism(types, offset)
             }
-            CanonicalFunction::BackpressureSet => self.backpressure_set(types, offset),
             CanonicalFunction::BackpressureInc => self.backpressure_inc(types, offset),
             CanonicalFunction::BackpressureDec => self.backpressure_dec(types, offset),
             CanonicalFunction::TaskReturn { result, options } => {
@@ -1393,19 +1392,6 @@ impl ComponentState {
         Ok(())
     }
 
-    fn backpressure_set(&mut self, types: &mut TypeAlloc, offset: usize) -> Result<()> {
-        if !self.features.cm_async() {
-            bail!(
-                offset,
-                "`backpressure.set` requires the component model async feature"
-            )
-        }
-
-        self.core_funcs
-            .push(types.intern_func_type(FuncType::new([ValType::I32], []), offset));
-        Ok(())
-    }
-
     fn backpressure_inc(&mut self, types: &mut TypeAlloc, offset: usize) -> Result<()> {
         if !self.features.cm_async() {
             bail!(

crates/wasmparser/src/validator/component.rs

@@ -947,9 +947,6 @@ impl Printer<'_, '_> {
                         Ok(())
                     })?;
                 }
-                CanonicalFunction::BackpressureSet => {
-                    self.print_intrinsic(state, "canon backpressure.set", &|_, _| Ok(()))?;
-                }
                 CanonicalFunction::BackpressureInc => {
                     self.print_intrinsic(state, "canon backpressure.inc", &|_, _| Ok(()))?;
                 }

crates/wasmprinter/src/component.rs

@@ -370,10 +370,6 @@ impl<'a> Encoder<'a> {
                     self.core_func_names.push(name);
                     self.funcs.thread_available_parallelism();
                 }
-                CoreFuncKind::BackpressureSet => {
-                    self.core_func_names.push(name);
-                    self.funcs.backpressure_set();
-                }
                 CoreFuncKind::BackpressureInc => {
                     self.core_func_names.push(name);
                     self.funcs.backpressure_inc();

crates/wast/src/component/binary.rs

@@ -54,7 +54,6 @@ pub enum CoreFuncKind<'a> {
     ThreadSpawnRef(CanonThreadSpawnRef<'a>),
     ThreadSpawnIndirect(CanonThreadSpawnIndirect<'a>),
     ThreadAvailableParallelism(CanonThreadAvailableParallelism),
-    BackpressureSet,
     BackpressureInc,
     BackpressureDec,
     TaskReturn(CanonTaskReturn<'a>),
@@ -126,9 +125,6 @@ impl<'a> CoreFuncKind<'a> {
             Ok(CoreFuncKind::ThreadSpawnIndirect(parser.parse()?))
         } else if l.peek::<kw::thread_available_parallelism>()? {
             Ok(CoreFuncKind::ThreadAvailableParallelism(parser.parse()?))
-        } else if l.peek::<kw::backpressure_set>()? {
-            parser.parse::<kw::backpressure_set>()?;
-            Ok(CoreFuncKind::BackpressureSet)
         } else if l.peek::<kw::backpressure_inc>()? {
             parser.parse::<kw::backpressure_inc>()?;
             Ok(CoreFuncKind::BackpressureInc)