Remove the finished_functions field in Instance

Turns out we don't actually need it anywhere any more! This removes an
allocation when instantiating.

Author: alexcrichton

crates/jit/src/instantiate.rs

@@ -14,7 +14,7 @@ use std::collections::HashMap;
 use std::sync::Arc;
 use thiserror::Error;
 use wasmtime_debug::create_gdbjit_image;
-use wasmtime_environ::entity::{BoxedSlice, PrimaryMap};
+use wasmtime_environ::entity::PrimaryMap;
 use wasmtime_environ::isa::TargetIsa;
 use wasmtime_environ::wasm::{DefinedFuncIndex, SignatureIndex};
 use wasmtime_environ::{
@@ -134,7 +134,7 @@ impl CompilationArtifacts {
     }
 }
 
-struct FinishedFunctions(BoxedSlice<DefinedFuncIndex, *mut [VMFunctionBody]>);
+struct FinishedFunctions(PrimaryMap<DefinedFuncIndex, *mut [VMFunctionBody]>);
 
 unsafe impl Send for FinishedFunctions {}
 unsafe impl Sync for FinishedFunctions {}
@@ -207,7 +207,7 @@ impl CompiledModule {
             None
         };
 
-        let finished_functions = FinishedFunctions(finished_functions.into_boxed_slice());
+        let finished_functions = FinishedFunctions(finished_functions);
 
         Ok(Self {
             module: Arc::new(module),
@@ -271,12 +271,10 @@ impl CompiledModule {
             trampolines.insert(signatures[i], trampoline.clone());
         }
 
-        let finished_functions = self.finished_functions.0.clone();
-
         InstanceHandle::new(
             self.module.clone(),
             self.code.clone(),
-            finished_functions,
+            &self.finished_functions.0,
             trampolines,
             imports,
             mem_creator,
@@ -310,7 +308,7 @@ impl CompiledModule {
     }
 
     /// Returns the map of all finished JIT functions compiled for this module
-    pub fn finished_functions(&self) -> &BoxedSlice<DefinedFuncIndex, *mut [VMFunctionBody]> {
+    pub fn finished_functions(&self) -> &PrimaryMap<DefinedFuncIndex, *mut [VMFunctionBody]> {
         &self.finished_functions.0
     }
 

crates/runtime/src/instance.rs

@@ -62,9 +62,6 @@ pub(crate) struct Instance {
     /// get removed. A missing entry is considered equivalent to an empty slice.
     passive_data: RefCell<HashMap<DataIndex, Arc<[u8]>>>,
 
-    /// Pointers to functions in executable memory.
-    finished_functions: BoxedSlice<DefinedFuncIndex, *mut [VMFunctionBody]>,
-
     /// Pointers to trampoline functions used to enter particular signatures
     trampolines: HashMap<VMSharedSignatureIndex, VMTrampoline>,
 
@@ -821,7 +818,7 @@ impl InstanceHandle {
     pub unsafe fn new(
         module: Arc<Module>,
         code: Arc<dyn Any>,
-        finished_functions: BoxedSlice<DefinedFuncIndex, *mut [VMFunctionBody]>,
+        finished_functions: &PrimaryMap<DefinedFuncIndex, *mut [VMFunctionBody]>,
         trampolines: HashMap<VMSharedSignatureIndex, VMTrampoline>,
         imports: Imports,
         mem_creator: Option<&dyn RuntimeMemoryCreator>,
@@ -864,7 +861,6 @@ impl InstanceHandle {
                 tables,
                 passive_elements: Default::default(),
                 passive_data,
-                finished_functions,
                 trampolines,
                 host_state,
                 interrupts,
@@ -944,7 +940,7 @@ impl InstanceHandle {
             let (func_ptr, vmctx) =
                 if let Some(def_index) = instance.module.defined_func_index(index) {
                     (
-                        NonNull::new(instance.finished_functions[def_index] as *mut _).unwrap(),
+                        NonNull::new(finished_functions[def_index] as *mut _).unwrap(),
                         instance.vmctx_ptr(),
                     )
                 } else {

crates/wasmtime/src/trampoline/create_handle.rs

@@ -36,7 +36,7 @@ pub(crate) fn create_handle(
         let handle = InstanceHandle::new(
             Arc::new(module),
             Arc::new(()),
-            finished_functions.into_boxed_slice(),
+            &finished_functions,
             trampolines,
             imports,
             store.memory_creator(),