Re-enable interceptor API on debug builds

But not on release builds to avoid the non-trivial overhead of
interception.

Author: kateinoigakukun

Sources/CLI/Run/Run.swift

@@ -54,6 +54,11 @@ struct Run: ParsableCommand {
         }
 
         let interceptor = try deriveInterceptor()
+        #if !DEBUG
+        guard interceptor == nil else {
+            fatalError("Internal Error: Interceptor API is unavailable with Release build due to performance reasons")
+        }
+        #endif
         defer { interceptor?.finalize() }
 
         let invoke: () throws -> Void

Sources/WasmKit/Execution/Instructions/Control.swift

@@ -119,9 +119,11 @@ extension ExecutionState {
 
     private mutating func endOfFunction(runtime: Runtime, currentFrame: Frame) throws {
         // When reached at "end" of function
-//        if let address = currentFrame.address {
-//            runtime.interceptor?.onExitFunction(address, store: runtime.store)
-//        }
+        #if DEBUG
+        if let address = currentFrame.address {
+            runtime.interceptor?.onExitFunction(address, store: runtime.store)
+        }
+        #endif
         let values = stack.popValues(count: currentFrame.arity)
         stack.popFrame()
         stack.push(values: values)

Sources/WasmKit/Execution/Runtime/ExecutionState.swift

@@ -62,7 +62,9 @@ extension ExecutionState {
     /// > Note:
     /// <https://webassembly.github.io/spec/core/exec/instructions.html#invocation-of-function-address>
     mutating func invoke(functionAddress address: FunctionAddress, runtime: Runtime) throws {
-        // runtime.interceptor?.onEnterFunction(address, store: runtime.store)
+        #if DEBUG
+        runtime.interceptor?.onEnterFunction(address, store: runtime.store)
+        #endif
 
         switch try runtime.store.function(at: address) {
         case let .host(function):