Switch to single-AppDomain execution

As I thought, remote method invocation seems to have been the major
bottleneck in /serialize.  Using a lighter-weight isolation protocol
has improved performance:

(time mono-sgen run/Niecza.exe -C CORE)
master:  user    0m30.898s
before:  user    1m26.453s
now:     user    0m29.246s

The new procedure uses only Assembly-level isolation: runtime
assemblies are renamed to have names starting with Run.; so CORE.dll
is the compiler's CORE and Run.CORE.dll is the user's.  This seemed
preferable over the reverse to avoid name clashes with perversely
named user modules.

Makefile

@@ -20,14 +20,14 @@ srcunits=CClass CgOp Op OpHelpers Sig RxOp STD NieczaGrammar Metamodel \
 	 NieczaPassSimplifier OptBeta NieczaPathSearch NieczaBackendDotnet \
 	 NieczaCompiler GetOptLong
 
-all: run/Niecza.exe obj/Kernel.dll obj/CORE.dll
+all: run/Niecza.exe obj/Run.Kernel.dll obj/Run.CORE.dll
 	@git describe --tags > VERSION
 
 $(patsubst %,boot/obj/%.nam,$(srcunits)): boot/obj/%.nam: .fetch-stamp src/%.pm6 boot/obj/CORE.nam
 	cd src && $(RUN_CLR) ../boot/run/Niecza.exe -Bnam -C $*
 	$(RUN_CLR) boot/obj/CLRBackend.exe boot/obj $*.nam $*.dll 0
 
-obj/CORE.dll: run/Niecza.exe obj/Kernel.dll lib/CORE.setting
+obj/Run.CORE.dll: run/Niecza.exe obj/Run.Kernel.dll lib/CORE.setting
 	$(RUN_CLR) run/Niecza.exe -C CORE
 
 run/Niecza.exe: .fetch-stamp $(patsubst %,boot/obj/%.nam,$(srcunits)) src/niecza
@@ -48,8 +48,8 @@ run/Niecza.exe: .fetch-stamp $(patsubst %,boot/obj/%.nam,$(srcunits)) src/niecza
 boot/obj/CompilerBlob.dll: .fetch-stamp src/CompilerBlob.cs
 	$(CSC) /target:library /out:boot/obj/CompilerBlob.dll /r:Kernel \
 	    /lib:boot/obj src/CompilerBlob.cs
-obj/Kernel.dll: $(patsubst %,lib/%,$(cskernel))
-	$(CSC) /target:exe /out:obj/Kernel.dll /lib:obj /unsafe+ \
+obj/Run.Kernel.dll: $(patsubst %,lib/%,$(cskernel))
+	$(CSC) /target:exe /out:obj/Run.Kernel.dll /lib:obj /unsafe+ \
 	    $(patsubst %,lib/%,$(cskernel))
 
 perl5: obj/Perl5Interpreter.dll obj/p5embed.so

lib/Builtins.cs

@@ -1628,16 +1628,12 @@ public partial class Builtins {
         System.Diagnostics.Process.Start(file, args).WaitForExit();
     }
 
-    [TrueGlobal] internal static AppDomain up_domain;
-    [TrueGlobal] static System.Collections.IDictionary upcall_receiver;
+    [TrueGlobal] internal static System.Collections.IDictionary upcall_receiver;
     internal static object UpCall(object[] args) {
-        if (upcall_receiver == null)
-            upcall_receiver = (System.Collections.IDictionary)
-                up_domain.CreateInstanceAndUnwrap("CompilerBlob", "Niecza.UpcallReceiver");
         return upcall_receiver[args];
     }
     public static Frame simple_eval(Frame th, Variable str) {
-        if (up_domain == null)
+        if (upcall_receiver == null)
             return Kernel.Die(th, "Cannot eval; no compiler available");
         SubInfo outer = th.caller.info;
         object r = UpCall(new object[] { "eval",

lib/CodeGen.cs

@@ -3420,6 +3420,11 @@ class NamProcessor {
     }
 
     public class Backend {
+        [TrueGlobal]
+        public static string obj_dir = AppDomain.CurrentDomain.BaseDirectory;
+        [TrueGlobal]
+        public static string prefix = (typeof(Backend).Assembly.GetName().Name == "Kernel") ? "" : "Run.";
+
         public static string LocStr(string fo, int lo, string fn, int ln) {
             return fn == fo ? " (see line " + lo + ")" :
                 " (see " + fo + " line " + lo + ")";
@@ -3613,8 +3618,9 @@ public class DowncallReceiver : CallReceiver {
                 object o = Handle.Unbox(args[1]);
                 return (o is SubInfo) ? "sub" : (o is RuntimeUnit) ? "unit" :
                     (o is STable) ? "type" : (o is Frame) ? "frame" : "unknown";
-            } else if (cmd == "set_parent") {
-                Builtins.up_domain = (AppDomain)args[1];
+            } else if (cmd == "set_binding") {
+                Backend.obj_dir = (string)args[1];
+                Builtins.upcall_receiver = (System.Collections.IDictionary)args[2];
                 return null;
             } else if (cmd == "push_compartment") {
                 Compartment.Push();

lib/Kernel.cs

@@ -593,7 +593,7 @@ public sealed class RuntimeUnit : IFreeze {
             if (name == "CORE")
                 Kernel.CreateBasicTypes();
 
-            this.asm_name = name.Replace("::", ".");
+            this.asm_name = Backend.prefix + name.Replace("::", ".");
             this.dll_name = asm_name + (main ? ".exe" : ".dll");
             our_subs = new List<SubInfo>();
         }
@@ -608,7 +608,7 @@ public sealed class RuntimeUnit : IFreeze {
                     new AssemblyName(asm_name),
                     (runnow ? AssemblyBuilderAccess.Run :
                         AssemblyBuilderAccess.Save),
-                    AppDomain.CurrentDomain.BaseDirectory);
+                    Backend.obj_dir);
             eu.mod_builder = runnow ?
                 eu.asm_builder.DefineDynamicModule(asm_name) :
                 eu.asm_builder.DefineDynamicModule(asm_name, dll_name);
@@ -636,7 +636,7 @@ public sealed class RuntimeUnit : IFreeze {
                         typeof(void), new Type[] { typeof(string[]) });
                 var il = mainb.GetILGenerator();
 
-                il.Emit(OpCodes.Ldstr, asm_name);
+                il.Emit(OpCodes.Ldstr, name);
                 il.Emit(OpCodes.Ldarg_0);
                 il.Emit(OpCodes.Call, typeof(Kernel).GetMethod("MainHandler"));
                 il.Emit(OpCodes.Ret);
@@ -663,7 +663,7 @@ public sealed class RuntimeUnit : IFreeze {
         public void Save() {
             EmitUnit eu = GenerateCode(false);
             eu.asm_builder.Save(dll_name);
-            reg.SaveUnit(asm_name, this);
+            reg.SaveUnit(name, this);
         }
 
         internal void SetConstants() {
@@ -856,7 +856,7 @@ public sealed class RuntimeUnit : IFreeze {
 
             n.name     = tb.String();
             string[] srcinfo = tb.Strings();
-            if (Builtins.up_domain != null) {
+            if (Builtins.upcall_receiver != null) {
                 object[] args = new object[srcinfo.Length + 1];
                 Array.Copy(srcinfo, 0, args, 1, srcinfo.Length);
                 args[0] = "check_dated";
@@ -872,8 +872,8 @@ public sealed class RuntimeUnit : IFreeze {
 
             n.depended_units = new HashSet<RuntimeUnit>(tb.RefsA<RuntimeUnit>());
 
-            n.assembly = Assembly.LoadFrom(System.IO.Path.Combine(AppDomain.CurrentDomain.BaseDirectory, n.dll_name));
-            n.type = tb.type = n.assembly.GetType(n.name, true);
+            n.assembly = Assembly.Load(n.asm_name);
+            n.type = tb.type = n.assembly.GetType(n.asm_name, true);
 
             int ncon = tb.Int();
             n.constants = new Dictionary<object,FieldInfo>();

lib/Serialize.cs

@@ -3,6 +3,7 @@
 using System.Security.Cryptography;
 using System.Collections.Generic;
 using System.Text;
+using Niecza.CLRBackend;
 
 // Here in Niecza we have four different kinds of unit scopes:
 //
@@ -111,8 +112,8 @@ struct ObjRef {
             if (units.TryGetValue(name, out su))
                 return su;
 
-            string file = Path.Combine(AppDomain.CurrentDomain.BaseDirectory,
-                    name + ".ser");
+            string file = Path.Combine(Backend.obj_dir, Backend.prefix +
+                    name.Replace("::",".") + ".ser");
             byte[] bytes = File.ReadAllBytes(file);
 
             su = new SerUnit();
@@ -163,8 +164,8 @@ struct ObjRef {
                 throw new InvalidOperationException("unit " +name+ " exists");
 
             bool success = false;
-            string file = Path.Combine(AppDomain.CurrentDomain.BaseDirectory,
-                    name + ".ser");
+            string file = Path.Combine(Backend.obj_dir, Backend.prefix +
+                    name.Replace("::",".") + ".ser");
 
             FreezeBuffer fb = new FreezeBuffer(this, su);
 

src/CompilerBlob.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Reflection;
 using System.Collections;
 using System.Collections.Generic;
 using System.Text;
@@ -45,29 +46,40 @@ public class UpcallReceiver : CallReceiver {
     }
 
     public class Downcaller {
-        static AppDomain subDomain;
         internal static Variable upcall_cb;
         static IDictionary responder;
         static P6any UnitP, StaticSubP, TypeP;
+        static string obj_dir;
+
+        // let the CLR load assemblies from obj/ too
+        static Assembly ObjLoader(object source, ResolveEventArgs e) {
+            string name = e.Name;
+            if (name.IndexOf(',') >= 0)
+                name = name.Substring(0, name.IndexOf(','));
+            string file = Path.Combine(obj_dir, name + ".dll");
+            if (File.Exists(file))
+                return Assembly.LoadFrom(file);
+            else
+                return null;
+        }
         // Better, but still fudgy.  Relies too much on path structure.
         public static void InitSlave(Variable cb, Variable unit,
                 Variable staticSub, Variable type) {
-            if (subDomain != null) return;
+            if (responder != null) return;
 
             UnitP = unit.Fetch();
             StaticSubP = staticSub.Fetch();
             TypeP = type.Fetch();
 
-            AppDomainSetup ads = new AppDomainSetup();
-            string obj = Path.GetFullPath(Path.Combine(AppDomain.CurrentDomain.BaseDirectory, Path.Combine("..", "obj")));
-            ads.ApplicationBase = obj;
-            string backend = Path.Combine(obj, "Kernel.dll");
-            subDomain = AppDomain.CreateDomain("zyg", null, ads);
+            obj_dir = Path.GetFullPath(Path.Combine(
+                        AppDomain.CurrentDomain.BaseDirectory,
+                        Path.Combine("..", "obj")));
+            AppDomain.CurrentDomain.AssemblyResolve += ObjLoader;
+
             upcall_cb = cb;
-            responder = (IDictionary)
-                subDomain.CreateInstanceFromAndUnwrap(backend,
-                        "Niecza.CLRBackend.DowncallReceiver");
-            RawDowncall("set_parent", AppDomain.CurrentDomain);
+            responder = (IDictionary) Activator.CreateInstance(Type.GetType(
+                    "Niecza.CLRBackend.DowncallReceiver,Run.Kernel", true));
+            RawDowncall("set_binding", obj_dir, new UpcallReceiver());
         }
         public static object RawDowncall(params object[] args) {
             return responder[args];