Add tracing of the stack height to full code generator.

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 419 matching lines @@
 }
 
 
 void FullCodeGenerator::AccumulatorValueContext::Plug(Register reg) const {
   __ Move(result_register(), reg);
 }
 
 
 void FullCodeGenerator::StackValueContext::Plug(Register reg) const {
   __ push(reg);
+  codegen()->increment_stack_height();
 }
 
 
 void FullCodeGenerator::TestContext::Plug(Register reg) const {
   // For simplicity we always test the accumulator register.
   __ Move(result_register(), reg);
   codegen()->PrepareForBailoutBeforeSplit(TOS_REG, false, NULL, NULL);
   codegen()->DoTest(this);
 }
 
 
 void FullCodeGenerator::EffectContext::PlugTOS() const {
   __ Drop(1);
+  codegen()->decrement_stack_height();
 }
 
 
 void FullCodeGenerator::AccumulatorValueContext::PlugTOS() const {
   __ pop(result_register());
+  codegen()->decrement_stack_height();
 }
 
 
 void FullCodeGenerator::StackValueContext::PlugTOS() const {
 }
 
 
 void FullCodeGenerator::TestContext::PlugTOS() const {
   // For simplicity we always test the accumulator register.
   __ pop(result_register());
+  codegen()->decrement_stack_height();
   codegen()->PrepareForBailoutBeforeSplit(TOS_REG, false, NULL, NULL);
   codegen()->DoTest(this);
 }
 
 
 void FullCodeGenerator::EffectContext::PrepareTest(
     Label* materialize_true,
     Label* materialize_false,
     Label** if_true,
     Label** if_false,
@@ skipping 475 matching lines @@
 
 
 void FullCodeGenerator::VisitEnterWithContextStatement(
     EnterWithContextStatement* stmt) {
   Comment cmnt(masm_, "[ EnterWithContextStatement");
   SetStatementPosition(stmt);
 
   VisitForStackValue(stmt->expression());
   PushFunctionArgumentForContextAllocation();
   __ CallRuntime(Runtime::kPushWithContext, 2);
+  decrement_stack_height();
   StoreToFrameField(StandardFrameConstants::kContextOffset, context_register());
 }
 
 
 void FullCodeGenerator::VisitExitContextStatement(ExitContextStatement* stmt) {
   Comment cmnt(masm_, "[ ExitContextStatement");
   SetStatementPosition(stmt);
 
   // Pop context.
   LoadContextField(context_register(), Context::PREVIOUS_INDEX);
@@ skipping 148 matching lines @@
   ASSERT(scope_->declarations()->is_empty());
   Visit(stmt->catch_block());
   scope_ = saved_scope;
   __ 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);
+    increment_stack_height(StackHandlerConstants::kSize / kPointerSize);
     Visit(stmt->try_block());
     __ PopTryHandler();
+    decrement_stack_height(StackHandlerConstants::kSize / kPointerSize);
   }
   __ bind(&done);
 }
 
 
 void FullCodeGenerator::VisitTryFinallyStatement(TryFinallyStatement* stmt) {
   Comment cmnt(masm_, "[ TryFinallyStatement");
   SetStatementPosition(stmt);
   // Try finally is compiled by setting up a try-handler on the stack while
   // executing the try body, and removing it again afterwards.
@@ skipping 11 matching lines @@
   //    handler code. The handler code then calls the finally-block before
   //    rethrowing the exception.
   //
   // The finally block must assume a return address on top of the stack
   // (or in the link register on ARM chips) and a value (return value or
   // exception) in the result register (rax/eax/r0), both of which must
   // be preserved. The return address isn't GC-safe, so it should be
   // cooked before GC.
   Label finally_entry;
   Label try_handler_setup;
+  const int original_stack_height = stack_height();
+  const int finally_block_stack_height = original_stack_height + 2;
+  const int try_block_stack_height = original_stack_height + 4;
+  STATIC_ASSERT(StackHandlerConstants::kSize / kPointerSize == 4);
 
   // Setup the try-handler chain. Use a call to
   // Jump to try-handler setup and try-block code. Use call to put try-handler
   // address on stack.
   __ Call(&try_handler_setup);
   // Try handler code. Return address of call is pushed on handler stack.
   {
     // This code is only executed during stack-handler traversal when an
     // exception is thrown. The execption is in the result register, which
     // is retained by the finally block.
     // Call the finally block and then rethrow the exception.
     __ Call(&finally_entry);
     __ push(result_register());
     __ CallRuntime(Runtime::kReThrow, 1);
   }
 
   __ bind(&finally_entry);
   {
     // Finally block implementation.
     Finally finally_block(this);
     EnterFinallyBlock();
+    set_stack_height(finally_block_stack_height);
     Visit(stmt->finally_block());
     ExitFinallyBlock();  // Return to the calling code.
   }
 
   __ bind(&try_handler_setup);
   {
     // Setup try handler (stack pointer registers).
     TryFinally try_block(this, &finally_entry);
     __ PushTryHandler(IN_JAVASCRIPT, TRY_FINALLY_HANDLER);
+    set_stack_height(try_block_stack_height);
     Visit(stmt->try_block());
     __ PopTryHandler();
+    set_stack_height(original_stack_height);
   }
   // Execute the finally block on the way out.  Clobber the unpredictable
   // value in the accumulator with one that's safe for GC.  The finally
   // block will unconditionally preserve the accumulator on the stack.
   ClearAccumulator();
   __ Call(&finally_entry);
 }
 
 
 void FullCodeGenerator::VisitDebuggerStatement(DebuggerStatement* stmt) {
 #ifdef ENABLE_DEBUGGER_SUPPORT
   Comment cmnt(masm_, "[ DebuggerStatement");
   SetStatementPosition(stmt);
 
   __ DebugBreak();
   // Ignore the return value.
 #endif
 }
 
 
 void FullCodeGenerator::VisitConditional(Conditional* expr) {
   Comment cmnt(masm_, "[ Conditional");
   Label true_case, false_case, done;
   VisitForControl(expr->condition(), &true_case, &false_case, &true_case);
 
   PrepareForBailoutForId(expr->ThenId(), NO_REGISTERS);
   __ bind(&true_case);
   SetExpressionPosition(expr->then_expression(),
                         expr->then_expression_position());
+  int start_stack_height = stack_height();
   if (context()->IsTest()) {
     const TestContext* for_test = TestContext::cast(context());
     VisitForControl(expr->then_expression(),
                     for_test->true_label(),
                     for_test->false_label(),
                     NULL);
   } else {
     VisitInCurrentContext(expr->then_expression());
     __ jmp(&done);
   }
 
   PrepareForBailoutForId(expr->ElseId(), NO_REGISTERS);
   __ bind(&false_case);
+  set_stack_height(start_stack_height);
   if (context()->IsTest()) ForwardBailoutToChild(expr);
   SetExpressionPosition(expr->else_expression(),
                         expr->else_expression_position());
   VisitInCurrentContext(expr->else_expression());
   // If control flow falls through Visit, merge it with true case here.
   if (!context()->IsTest()) {
     __ bind(&done);
   }
 }
 
@@ skipping 20 matching lines @@
 
 void FullCodeGenerator::VisitSharedFunctionInfoLiteral(
     SharedFunctionInfoLiteral* expr) {
   Comment cmnt(masm_, "[ SharedFunctionInfoLiteral");
   EmitNewClosure(expr->shared_function_info(), false);
 }
 
 
 void FullCodeGenerator::VisitThrow(Throw* expr) {
   Comment cmnt(masm_, "[ Throw");
+  // Throw has no effect on the stack height or the current expression context.
+  // Usually the expression context is null, because throw is a statement.
   VisitForStackValue(expr->exception());
   __ CallRuntime(Runtime::kThrow, 1);
+  decrement_stack_height();
   // 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;
@@ skipping 25 matching lines @@
   }
 
   return false;
 }
 
 
 #undef __
 
 
 } }  // namespace v8::internal