Stop using with explicitly to implement try/catch.

src/full-codegen.cc

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 169 matching lines @@
 
 
 void BreakableStatementChecker::VisitObjectLiteral(ObjectLiteral* expr) {
 }
 
 
 void BreakableStatementChecker::VisitArrayLiteral(ArrayLiteral* expr) {
 }
 
 
-void BreakableStatementChecker::VisitCatchExtensionObject(
-    CatchExtensionObject* expr) {
-}
-
-
 void BreakableStatementChecker::VisitAssignment(Assignment* expr) {
   // If assigning to a property (including a global property) the assignment is
   // breakable.
   Variable* var = expr->target()->AsVariableProxy()->AsVariable();
   Property* prop = expr->target()->AsProperty();
   if (prop != NULL || (var != NULL && var->is_global())) {
     is_breakable_ = true;
     return;
   }
 
@@ skipping 750 matching lines @@
 
   EmitReturnSequence();
 }
 
 
 void FullCodeGenerator::VisitWithEnterStatement(WithEnterStatement* stmt) {
   Comment cmnt(masm_, "[ WithEnterStatement");
   SetStatementPosition(stmt);
 
   VisitForStackValue(stmt->expression());
-  if (stmt->is_catch_block()) {
-    __ CallRuntime(Runtime::kPushCatchContext, 1);
-  } else {
-    __ CallRuntime(Runtime::kPushContext, 1);
-  }
-  // Both runtime calls return the new context in both the context and the
-  // result registers.
-
-  // Update local stack frame context field.
+  __ CallRuntime(Runtime::kPushContext, 1);
   StoreToFrameField(StandardFrameConstants::kContextOffset, context_register());
 }
 
 
 void FullCodeGenerator::VisitWithExitStatement(WithExitStatement* stmt) {
   Comment cmnt(masm_, "[ WithExitStatement");
   SetStatementPosition(stmt);
 
   // Pop context.
   LoadContextField(context_register(), Context::PREVIOUS_INDEX);
@@ skipping 126 matching lines @@
   // At this point, the exception is in a register, and store it in
   // the temporary local variable (prints as ".catch-var") before
   // executing the catch block. The catch block has been rewritten
   // to introduce a new scope to bind the catch variable and to remove
   // that scope again afterwards.
 
   Label try_handler_setup, catch_entry, done;
   __ Call(&try_handler_setup);
   // Try handler code, exception in result register.
 
-  // Store exception in local .catch variable before executing catch block.
-  {
-    // The catch variable is *always* a variable proxy for a local variable.
-    Variable* catch_var = stmt->catch_var()->AsVariableProxy()->AsVariable();
-    ASSERT_NOT_NULL(catch_var);
-    Slot* variable_slot = catch_var->AsSlot();
-    ASSERT_NOT_NULL(variable_slot);
-    ASSERT_EQ(Slot::LOCAL, variable_slot->type());
-    StoreToFrameField(SlotOffset(variable_slot), result_register());
+  // Extend the context before executing the catch block.
+  { Comment cmnt(masm_, "[ Extend catch context");
+    __ push(stmt->name());
+    __ push(result_register());
+    __ CallRuntime(Runtime::kCreateCatchExtensionObject, 2);
+    __ push(result_register());
+    __ CallRuntime(Runtime::kPushCatchContext, 1);
+    StoreToFrameField(StandardFrameConstants::kContextOffset,
+                      context_register());
   }
 
   Visit(stmt->catch_block());
   __ jmp(&done);
 
   // Try block code. Sets up the exception handler chain.
   __ bind(&try_handler_setup);
   {
     TryCatch try_block(this, &catch_entry);
     __ PushTryHandler(IN_JAVASCRIPT, TRY_CATCH_HANDLER);
@@ skipping 135 matching lines @@
 }
 
 
 void FullCodeGenerator::VisitSharedFunctionInfoLiteral(
     SharedFunctionInfoLiteral* expr) {
   Comment cmnt(masm_, "[ SharedFunctionInfoLiteral");
   EmitNewClosure(expr->shared_function_info(), false);
 }
 
 
-void FullCodeGenerator::VisitCatchExtensionObject(CatchExtensionObject* expr) {
-  // Call runtime routine to allocate the catch extension object and
-  // assign the exception value to the catch variable.
-  Comment cmnt(masm_, "[ CatchExtensionObject");
-  VisitForStackValue(expr->key());
-  VisitForStackValue(expr->value());
-  // Create catch extension object.
-  __ CallRuntime(Runtime::kCreateCatchExtensionObject, 2);
-  context()->Plug(result_register());
-}
-
-
 void FullCodeGenerator::VisitThrow(Throw* expr) {
   Comment cmnt(masm_, "[ Throw");
   VisitForStackValue(expr->exception());
   __ CallRuntime(Runtime::kThrow, 1);
   // Never returns here.
 }
 
 
 int FullCodeGenerator::TryFinally::Exit(int stack_depth) {
   // The macros used here must preserve the result register.
   __ Drop(stack_depth);
   __ PopTryHandler();
   __ Call(finally_entry_);
   return 0;
 }
 
 
 int FullCodeGenerator::TryCatch::Exit(int stack_depth) {
   // The macros used here must preserve the result register.
   __ Drop(stack_depth);
   __ PopTryHandler();
   return 0;
 }
 
 
 #undef __
 
 
 } }  // namespace v8::internal