mcs/class/Microsoft.JScript/Microsoft.JScript/CodeGenerator.cs

   1 //
   2 // CodeGenerator.cs
   3 //
   4 // Author:
   5 //      Cesar Lopez Nataren (cesar@ciencias.unam.mx)
   6 //
   7 // (C) 2003, 2004 Cesar Lopez Nataren
   8 //
   9
  10 //
  11 // Permission is hereby granted, free of charge, to any person obtaining
  12 // a copy of this software and associated documentation files (the
  13 // "Software"), to deal in the Software without restriction, including
  14 // without limitation the rights to use, copy, modify, merge, publish,
  15 // distribute, sublicense, and/or sell copies of the Software, and to
  16 // permit persons to whom the Software is furnished to do so, subject to
  17 // the following conditions:
  18 //
  19 // The above copyright notice and this permission notice shall be
  20 // included in all copies or substantial portions of the Software.
  21 //
  22 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  23 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  24 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  25 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  26 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  27 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  28 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  29 //
  30
  31 using System;
  32 using System.IO;
  33 using System.Reflection;
  34 using System.Reflection.Emit;
  35 using System.Threading;
  36 using Microsoft.JScript.Vsa;
  37 using System.Runtime.CompilerServices;
  38
  39 namespace Microsoft.JScript {
  40
  41         internal class EmitContext {
  42
  43                 internal TypeBuilder type_builder;
  44                 internal ILGenerator ig;
  45                 internal ModuleBuilder mod_builder;
  46
  47                 internal Label LoopBegin, LoopEnd;
  48
  49                 internal EmitContext (TypeBuilder type)
  50                 {
  51                         type_builder = type;
  52
  53                         if (type_builder != null) {
  54                                 MethodBuilder global_code =  type_builder.DefineMethod (
  55                                                                         "Global Code",
  56                                                                         MethodAttributes.Public,
  57                                                                         typeof (System.Object),
  58                                                                         new Type [] {});
  59                                 ig = global_code.GetILGenerator ();
  60                         }
  61                 }
  62
  63                 internal EmitContext (TypeBuilder type_builder, ModuleBuilder mod_builder, ILGenerator ig)
  64                 {
  65                         this.type_builder = type_builder;
  66                         this.mod_builder = mod_builder;
  67                         this.ig = ig;
  68                 }
  69         }
  70
  71         public class CodeGenerator {
  72
  73                 private static string MODULE = "JScript Module";
  74
  75                 internal static string mod_name;
  76                 internal static AppDomain app_domain;
  77                 internal static AssemblyName assembly_name;
  78                 internal static AssemblyBuilder assembly_builder;
  79                 internal static ModuleBuilder module_builder;
  80
  81                 internal static string Basename (string name)
  82                 {
  83                         int pos = name.LastIndexOf ('/');
  84
  85                         if (pos != -1)
  86                                 return name.Substring (pos + 1);
  87
  88                         pos = name.LastIndexOf ('\\');
  89                         if (pos != -1)
  90                                 return name.Substring (pos + 1);
  91
  92                         return name;
  93                 }
  94
  95                 internal static string Dirname (string name)
  96                 {
  97                         int pos = name.LastIndexOf ('/');
  98
  99                         if (pos != -1)
 100                                 return name.Substring (0, pos);
 101
 102                         pos = name.LastIndexOf ('\\');
 103                         if (pos != -1)
 104                                 return name.Substring (0, pos);
 105
 106                         return ".";
 107                 }
 108
 109                 internal static void Init (string file_name)
 110                 {
 111                         app_domain = Thread.GetDomain ();
 112
 113                         assembly_name = new AssemblyName ();
 114                         assembly_name.Name = Path.GetFileNameWithoutExtension (file_name);
 115                         mod_name = MODULE;
 116
 117                         assembly_builder = app_domain.DefineDynamicAssembly (
 118                                              assembly_name,
 119                                              AssemblyBuilderAccess.RunAndSave,
 120                                              Dirname (file_name));
 121
 122                         ConstructorInfo ctr_info = typeof (Microsoft.JScript.ReferenceAttribute).GetConstructor (new Type [] { typeof (string) });
 123                         // FIXME: find out which is the blob.
 124                         byte [] blob  = new byte [] {};
 125                         assembly_builder.SetCustomAttribute (ctr_info, blob);
 126
 127                         module_builder = assembly_builder.DefineDynamicModule (
 128                                                mod_name,
 129                                                Basename (assembly_name.Name + ".exe"),
 130                                                false);
 131                 }
 132
 133                 internal static string trim_extension (string file_name)
 134                 {
 135                         int index = file_name.LastIndexOf ('.');
 136
 137                         if (index < 0)
 138                                 return file_name;
 139                         else
 140                                 return file_name.Substring (0, index);
 141                 }
 142
 143                 internal static void Save (string target_name)
 144                 {
 145                         assembly_builder.Save (CodeGenerator.Basename (target_name));
 146                 }
 147
 148                 internal static void Emit (AST prog)
 149                 {
 150                         if (prog == null)
 151                                 return;
 152
 153                         TypeBuilder type_builder;
 154                         type_builder = module_builder.DefineType ("JScript 0", TypeAttributes.Public);
 155
 156                         type_builder.SetParent (typeof (GlobalScope));
 157                         type_builder.SetCustomAttribute (new CustomAttributeBuilder
 158                                                          (typeof (CompilerGlobalScopeAttribute).GetConstructor (new Type [] {}), new object [] {}));
 159
 160                         EmitContext ec = new EmitContext (type_builder);
 161                         ec.mod_builder = module_builder;
 162                         ILGenerator global_code = ec.ig;
 163
 164                         emit_default_script_constructor (ec);
 165                         emit_default_init_global_code (global_code);
 166                         prog.Emit (ec);
 167                         emit_default_end_global_code (global_code);
 168                         ec.type_builder.CreateType ();
 169
 170                         //
 171                         // Build the default 'JScript Main' class
 172                         //
 173                         ec.type_builder = module_builder.DefineType ("JScript Main");
 174                         emit_jscript_main (ec.type_builder);
 175                         ec.type_builder.CreateType ();
 176                 }
 177
 178                 internal static void emit_default_init_global_code (ILGenerator ig)
 179                 {
 180                         ig.Emit (OpCodes.Ldarg_0);
 181                         ig.Emit (OpCodes.Ldfld, typeof (ScriptObject).GetField ("engine"));
 182                         ig.Emit (OpCodes.Ldarg_0);
 183                         ig.Emit (OpCodes.Call,
 184                                 typeof (VsaEngine).GetMethod ("PushScriptObject",
 185                                                               new Type [] { typeof (ScriptObject)}));
 186                 }
 187
 188                 internal static void emit_default_end_global_code (ILGenerator ig)
 189                 {
 190                         ig.Emit (OpCodes.Ldnull);
 191                         ig.Emit (OpCodes.Ldarg_0);
 192                         ig.Emit (OpCodes.Ldfld, typeof (ScriptObject).GetField ("engine"));
 193                         ig.Emit (OpCodes.Call, typeof (VsaEngine).GetMethod ("PopScriptObject"));
 194                         ig.Emit (OpCodes.Pop);
 195                         ig.Emit (OpCodes.Ret);
 196                 }
 197
 198                 internal static void emit_default_script_constructor (EmitContext ec)
 199                 {
 200                         ConstructorBuilder cons_builder;
 201                         TypeBuilder tb = ec.type_builder;
 202                         cons_builder = tb.DefineConstructor (MethodAttributes.Public,
 203                                                              CallingConventions.Standard,
 204                                                              new Type [] { typeof (GlobalScope) });
 205
 206                         ILGenerator ig = cons_builder.GetILGenerator ();
 207                         ig.Emit (OpCodes.Ldarg_0);
 208                         ig.Emit (OpCodes.Ldarg_1);
 209                         ig.Emit (OpCodes.Dup);
 210                         ig.Emit (OpCodes.Ldfld,
 211                                  typeof (ScriptObject).GetField ("engine"));
 212
 213                         ig.Emit (OpCodes.Call,
 214                                  typeof (GlobalScope).GetConstructor (new Type [] {typeof (GlobalScope),
 215                                                                                    typeof (VsaEngine)}));
 216                         ig.Emit (OpCodes.Ret);
 217                 }
 218
 219                 internal static void emit_jscript_main (TypeBuilder tb)
 220                 {
 221                         emit_jscript_main_constructor (tb);
 222                         emit_jscript_main_entry_point (tb);
 223                 }
 224
 225                 internal static void emit_jscript_main_constructor (TypeBuilder tb)
 226                 {
 227                         ConstructorBuilder cons = tb.DefineConstructor (MethodAttributes.Public,
 228                                                                         CallingConventions.Standard,
 229                                                                         new Type [] {});
 230                         ILGenerator ig = cons.GetILGenerator ();
 231                         ig.Emit (OpCodes.Ldarg_0);
 232                         ig.Emit (OpCodes.Call, typeof (Object).GetConstructor (new Type [] {}));
 233                         ig.Emit (OpCodes.Ret);
 234                 }
 235
 236                 internal static void emit_jscript_main_entry_point (TypeBuilder tb)
 237                 {
 238                         MethodBuilder method;
 239                         method = tb.DefineMethod ("Main",
 240                                                   MethodAttributes.Public | MethodAttributes.Static,
 241                                                   typeof (void), new Type [] {typeof (String [])});
 242
 243                         method.SetCustomAttribute (new CustomAttributeBuilder
 244                                                    (typeof (STAThreadAttribute).GetConstructor (
 245                                                                                         new Type [] {}),
 246                                                      new object [] {}));
 247
 248                         ILGenerator ig = method.GetILGenerator ();
 249
 250                         ig.DeclareLocal (typeof (GlobalScope));
 251
 252                         ig.Emit (OpCodes.Ldc_I4_1);
 253                         ig.Emit (OpCodes.Ldc_I4_1);
 254                         ig.Emit (OpCodes.Newarr, typeof (string));
 255                         ig.Emit (OpCodes.Dup);
 256                         ig.Emit (OpCodes.Ldc_I4_0);
 257
 258                         ig.Emit (OpCodes.Ldstr,
 259                                  "mscorlib, Version=1.0.3300.0, Culture=neutral, Pub" +
 260                                  "licKeyToken=b77a5c561934e089");
 261
 262                         ig.Emit (OpCodes.Stelem_Ref);
 263
 264                         ig.Emit (OpCodes.Call,
 265                                  typeof (VsaEngine).GetMethod ("CreateEngineAndGetGlobalScope",
 266                                                                new Type [] {typeof (bool),
 267                                                                             typeof (string [])}));
 268                         ig.Emit (OpCodes.Stloc_0);
 269                         ig.Emit (OpCodes.Ldloc_0);
 270
 271                         ig.Emit (OpCodes.Newobj,
 272                                  assembly_builder.GetType ("JScript 0").GetConstructor (
 273                                                                         new Type [] {typeof (GlobalScope)}));
 274                         ig.Emit (OpCodes.Call,
 275                                  assembly_builder.GetType ("JScript 0").GetMethod (
 276                                                                            "Global Code", new Type [] {}));
 277                         ig.Emit (OpCodes.Pop);
 278                         ig.Emit (OpCodes.Ret);
 279
 280                         assembly_builder.SetEntryPoint (method);
 281                 }
 282
 283                 public static void Run (string file_name, AST prog)
 284                 {
 285                         CodeGenerator.Init (file_name);
 286                         CodeGenerator.Emit (prog);
 287                         CodeGenerator.Save (trim_extension (file_name) + ".exe");
 288                 }
 289
 290                 static void emit_default_case (EmitContext ec, AST ast, OpCode op, Label lbl)
 291                 {
 292                         ast.Emit (ec);
 293                         if (need_convert_to_boolean (ast))
 294                                 emit_to_boolean (ast, ec.ig, 0);
 295                         ec.ig.Emit (op, lbl);
 296                 }
 297
 298                 static void ft_binary_recursion (EmitContext ec, AST ast, Label lbl)
 299                 {
 300                         ILGenerator ig = ec.ig;
 301                         if (ast is Binary) {
 302                                 Binary b = ast as Binary;
 303                                 switch (b.op) {
 304                                 case JSToken.LogicalOr:
 305                                         Label ftLb = ig.DefineLabel ();
 306                                         fall_false (ec, b.left, ftLb);
 307                                         fall_true (ec, b.right, lbl);
 308                                         ig.MarkLabel (ftLb);
 309                                         break;
 310                                 case JSToken.LogicalAnd:
 311                                         fall_true (ec, b.left, lbl);
 312                                         fall_true (ec, b.right, lbl);
 313                                         break;
 314
 315                                 case JSToken.LessThan:
 316                                         ig.Emit (OpCodes.Ldc_I4_0);
 317                                         ig.Emit (OpCodes.Conv_R8);
 318                                         ig.Emit (OpCodes.Blt, lbl);
 319                                         break;
 320                                 }
 321                         }
 322                 }
 323
 324                 static void ft_emit_equality (EmitContext ec, AST ast, Label lbl)
 325                 {
 326                         ILGenerator ig = ec.ig;
 327                         Equality eq = ast as Equality;
 328
 329                         switch (eq.op) {
 330                         case JSToken.NotEqual:
 331                                 ig.Emit (OpCodes.Brtrue, lbl);
 332                                 break;
 333                         case JSToken.Equal:
 334                                 ig.Emit (OpCodes.Brfalse, lbl);
 335                                 break;
 336                         }
 337                 }
 338
 339                 internal static void fall_true (EmitContext ec, AST ast, Label lbl)
 340                 {
 341                         Type type = ast.GetType ();
 342
 343                         if (type == typeof (Expression)) {
 344                                 Expression exp = ast as Expression;
 345                                 exp.Emit (ec);
 346                                 AST last_exp = (AST) exp.exprs [exp.exprs.Count - 1];
 347
 348                                 if (last_exp is Binary)
 349                                         ft_binary_recursion (ec, last_exp, lbl);
 350                                 else if (last_exp is Equality)
 351                                         ft_emit_equality (ec, last_exp, lbl);
 352                         } else if (type == typeof (Binary))
 353                                 ft_binary_recursion (ec, ast, lbl);
 354                         else
 355                                 emit_default_case (ec, ast, OpCodes.Brfalse, lbl);
 356                 }
 357
 358                 static void ff_emit_relational (EmitContext ec, AST ast, Label lbl)
 359                 {
 360                         ILGenerator ig = ec.ig;
 361                         Relational r = ast as Relational;
 362                         r.Emit (ec);
 363
 364                         switch (r.op) {
 365                         case JSToken.LessThan:
 366                                 ig.Emit (OpCodes.Ldc_I4_0);
 367                                 ig.Emit (OpCodes.Conv_R8);
 368                                 ig.Emit (OpCodes.Blt, lbl);
 369                                 break;
 370                         }
 371                 }
 372
 373                 static void ff_binary_recursion (EmitContext ec, AST ast, Label lbl)
 374                 {
 375                         ILGenerator ig = ec.ig;
 376                         Binary b = ast as Binary;
 377
 378                         switch (b.op) {
 379                         case JSToken.LogicalOr:
 380                                 fall_false (ec, b.left, lbl);
 381                                 fall_false (ec, b.right, lbl);
 382                                 break;
 383
 384                         case JSToken.LogicalAnd:
 385                                 Label ftLb = ig.DefineLabel ();
 386                                 fall_true (ec, b.left, ftLb);
 387                                 fall_false (ec, b.right, lbl);
 388                                 ig.MarkLabel (ftLb);
 389                                 break;
 390                         }
 391                 }
 392
 393                 static void ff_emit_equality_cond (EmitContext ec, AST ast, Label lbl)
 394                 {
 395                         ILGenerator ig = ec.ig;
 396                         Equality eq = ast as Equality;
 397                         eq.Emit (ec);
 398
 399                         switch (eq.op) {
 400                         case JSToken.NotEqual:
 401                         case JSToken.Equal:
 402                                 ig.Emit (OpCodes.Brfalse, lbl);
 403                                 break;
 404                         }
 405                 }
 406
 407                 internal static void fall_false (EmitContext ec, AST ast, Label lbl)
 408                 {
 409                         Type type = ast.GetType ();
 410
 411                         if (type == typeof (Expression)) {
 412                                 Expression exp = ast as Expression;
 413
 414                                 if (exp.Size > 1)
 415                                         exp.Emit (ec);
 416
 417                                 AST last_exp = (AST) exp.exprs [exp.exprs.Count - 1];
 418
 419                                 if (last_exp is Relational)
 420                                         ff_emit_relational (ec, last_exp, lbl);
 421                                 else if (last_exp is Binary)
 422                                         ff_binary_recursion (ec, last_exp, lbl);
 423                                 else if (last_exp is Identifier || last_exp is BooleanLiteral)
 424                                         emit_default_case (ec, last_exp, OpCodes.Brtrue, lbl);
 425                                 else if (last_exp is Equality)
 426                                         ff_emit_equality_cond (ec, last_exp, lbl);
 427                                 else {
 428                                         Console.WriteLine ("fall_false, last_exp.GetType () == {0}", last_exp);
 429                                         throw new Exception ("uknown type: " + last_exp.GetType ().ToString ());
 430                                 }
 431                         } else if (type == typeof (Binary))
 432                                 ff_binary_recursion (ec, ast, lbl);
 433                         else
 434                                 emit_default_case (ec, ast, OpCodes.Brtrue, lbl);
 435                 }
 436
 437                 internal static void emit_to_boolean (AST ast, ILGenerator ig, int i)
 438                 {
 439                         ig.Emit (OpCodes.Ldc_I4, i);
 440                         ig.Emit (OpCodes.Call, typeof (Convert).GetMethod ("ToBoolean",
 441                                                                            new Type [] { typeof (object), typeof (Boolean)}));
 442                 }
 443
 444                 internal static bool need_convert_to_boolean (AST ast)
 445                 {
 446                         if (ast == null)
 447                                 return false;
 448
 449                         if (ast is Identifier)
 450                                 return true;
 451                         else if (ast is Expression) {
 452                                 Expression exp = ast as Expression;
 453                                 int n = exp.exprs.Count - 1;
 454                                 AST tmp = (AST) exp.exprs [n];
 455                                 if (tmp is Equality || tmp is Relational || tmp is BooleanLiteral)
 456                                         return false;
 457                                 else
 458                                         return true;
 459                         } else
 460                                 return false;
 461                 }
 462
 463                 //
 464                 // Loads a current VsaEngine
 465                 //
 466                 internal static void load_engine (AST parent, ILGenerator ig)
 467                 {
 468                         //
 469                         // If we are in a function declaration at global level,
 470                         // we must load the engine associated to the current 'JScript N' instance,
 471                         // otherwise pick up the engine at second place in method's signature.
 472                         //
 473                         if (parent == null ||  parent.GetType () == typeof (ScriptBlock)) {
 474                                 ig.Emit (OpCodes.Ldarg_0);
 475                                 ig.Emit (OpCodes.Ldfld, typeof (ScriptObject).GetField ("engine"));
 476                         } else if (parent != null &&  parent.GetType () == typeof (FunctionDeclaration ))
 477                                 ig.Emit (OpCodes.Ldarg_1);
 478                 }
 479         }
 480 }