Checking for stack height equality between full codegen and hydrogen.

src/full-codegen.cc

Index: src/full-codegen.cc
diff --git a/src/full-codegen.cc b/src/full-codegen.cc
index 6ae927c9018a16a5462f2448f5ae79bdc3e997a1..1409f90629b8e2e2fed0380955bc0abd19735d42 100644
--- a/src/full-codegen.cc
+++ b/src/full-codegen.cc
@@ -381,6 +381,9 @@ void FullCodeGenerator::PopulateDeoptimizationData(Handle<Code> code) {
   for (int i = 0; i < length; i++) {
     data->SetAstId(i, bailout_entries_[i].id);
     data->SetPcAndState(i, Smi::FromInt(bailout_entries_[i].pc_and_state));
+#if defined(COMPARE_OPT_STACK_HEIGHT)
+    data->SetStackHeight(i, Smi::FromInt(bailout_entries_[i].stack_height));
+#endif
   }
   code->set_deoptimization_data(*data);
 }
@@ -448,7 +451,12 @@ void FullCodeGenerator::RecordJSReturnSite(Call* call) {
 void FullCodeGenerator::PrepareForBailoutForId(BailoutId id, State state) {
   // There's no need to prepare this code for bailouts from already optimized
   // code or code that can't be optimized.
-  if (!info_->HasDeoptimizationSupport()) return;
+  if (!info_->HasDeoptimizationSupport()) {
+    // We still need to insert the check to make sure that we generate exactly
+    // the same code
+    CheckStackHeight();
+    return;
+  }
   unsigned pc_and_state =
       StateField::encode(state) | PcField::encode(masm_->pc_offset());
   ASSERT(Smi::IsValid(pc_and_state));
@@ -457,8 +465,11 @@ void FullCodeGenerator::PrepareForBailoutForId(BailoutId id, State state) {
     ASSERT(bailout_entries_[i].id != id);
   }
 #endif
-  BailoutEntry entry = { id, pc_and_state };
+  // If the we store the top of the stack register, pretend it is on the stack
+  int stack_height = stack_height_.get() + (state == TOS_REG ? 1 : 0);
+  BailoutEntry entry = { id, pc_and_state, stack_height };
   bailout_entries_.Add(entry, zone());
+  CheckStackHeight();
 }
 
 
@@ -492,7 +503,7 @@ void FullCodeGenerator::AccumulatorValueContext::Plug(Register reg) const {
 
 
 void FullCodeGenerator::StackValueContext::Plug(Register reg) const {
-  __ Push(reg);
+  codegen()->AsmPush(reg);
 }
 
 
@@ -505,12 +516,12 @@ void FullCodeGenerator::TestContext::Plug(Register reg) const {
 
 
 void FullCodeGenerator::EffectContext::PlugTOS() const {
-  __ Drop(1);
+  codegen()->AsmDrop(1);
 }
 
 
 void FullCodeGenerator::AccumulatorValueContext::PlugTOS() const {
-  __ Pop(result_register());
+  codegen()->AsmPop(result_register());
 }
 
 
@@ -520,7 +531,7 @@ void FullCodeGenerator::StackValueContext::PlugTOS() const {
 
 void FullCodeGenerator::TestContext::PlugTOS() const {
   // For simplicity we always test the accumulator register.
-  __ Pop(result_register());
+  codegen()->AsmPop(result_register());
   codegen()->PrepareForBailoutBeforeSplit(condition(), false, NULL, NULL);
   codegen()->DoTest(this);
 }
@@ -597,9 +608,9 @@ void FullCodeGenerator::AllocateModules(ZoneList<Declaration*>* declarations) {
 
         // Set up module context.
         ASSERT(scope->interface()->Index() >= 0);
-        __ Push(Smi::FromInt(scope->interface()->Index()));
-        __ Push(scope->GetScopeInfo());
-        __ CallRuntime(Runtime::kHiddenPushModuleContext, 2);
+        AsmPushSmi(Smi::FromInt(scope->interface()->Index()));
+        AsmPushHandle(scope->GetScopeInfo());
+        AsmCallRuntime(Runtime::kHiddenPushModuleContext, 2);
         StoreToFrameField(StandardFrameConstants::kContextOffset,
                           context_register());
 
@@ -688,6 +699,7 @@ void FullCodeGenerator::VisitDeclarations(
     // This is a scope hosting modules. Allocate a descriptor array to pass
     // to the runtime for initialization.
     Comment cmnt(masm_, "[ Allocate modules");
+
     ASSERT(scope_->is_global_scope());
     modules_ =
         isolate()->factory()->NewFixedArray(scope_->num_modules(), TENURED);
@@ -737,9 +749,9 @@ void FullCodeGenerator::VisitModuleLiteral(ModuleLiteral* module) {
 
   // Set up module context.
   ASSERT(interface->Index() >= 0);
-  __ Push(Smi::FromInt(interface->Index()));
-  __ Push(Smi::FromInt(0));
-  __ CallRuntime(Runtime::kHiddenPushModuleContext, 2);
+  AsmPushSmi(Smi::FromInt(interface->Index()));
+  AsmPushSmi(Smi::FromInt(0));
+  AsmCallRuntime(Runtime::kHiddenPushModuleContext, 2);
   StoreToFrameField(StandardFrameConstants::kContextOffset, context_register());
 
   {
@@ -970,32 +982,32 @@ void FullCodeGenerator::VisitLogicalExpression(BinaryOperation* expr) {
     } else {
       VisitForControl(left, test->true_label(), &eval_right, &eval_right);
     }
-    PrepareForBailoutForId(right_id, NO_REGISTERS);
     __ bind(&eval_right);
-
+    PrepareForBailoutForId(right_id, NO_REGISTERS);
   } else if (context()->IsAccumulatorValue()) {
     VisitForAccumulatorValue(left);
     // We want the value in the accumulator for the test, and on the stack in
     // case we need it.
-    __ Push(result_register());
+    AsmPush(result_register());
     Label discard, restore;
     if (is_logical_and) {
       DoTest(left, &discard, &restore, &restore);
     } else {
       DoTest(left, &restore, &discard, &restore);
     }
+    StackHeightWrapper branch_stack_height = CurrentStackHeight();
     __ bind(&restore);
-    __ Pop(result_register());
+    AsmPop(result_register());
     __ jmp(&done);
     __ bind(&discard);
-    __ Drop(1);
+    SetStackHeight(branch_stack_height);
+    AsmDrop(1);
     PrepareForBailoutForId(right_id, NO_REGISTERS);
-
   } else if (context()->IsStackValue()) {
     VisitForAccumulatorValue(left);
     // We want the value in the accumulator for the test, and on the stack in
     // case we need it.
-    __ Push(result_register());
+    AsmPush(result_register());
     Label discard;
     if (is_logical_and) {
       DoTest(left, &discard, &done, &discard);
@@ -1003,9 +1015,8 @@ void FullCodeGenerator::VisitLogicalExpression(BinaryOperation* expr) {
       DoTest(left, &done, &discard, &discard);
     }
     __ bind(&discard);
-    __ Drop(1);
+    AsmDrop(1);
     PrepareForBailoutForId(right_id, NO_REGISTERS);
-
   } else {
     ASSERT(context()->IsEffect());
     Label eval_right;
@@ -1014,8 +1025,8 @@ void FullCodeGenerator::VisitLogicalExpression(BinaryOperation* expr) {
     } else {
       VisitForControl(left, &done, &eval_right, &eval_right);
     }
-    PrepareForBailoutForId(right_id, NO_REGISTERS);
     __ bind(&eval_right);
+    PrepareForBailoutForId(right_id, NO_REGISTERS);
   }
 
   VisitInDuplicateContext(right);
@@ -1056,9 +1067,9 @@ void FullCodeGenerator::VisitBlock(Block* stmt) {
     scope_ = stmt->scope();
     ASSERT(!scope_->is_module_scope());
     { Comment cmnt(masm_, "[ Extend block context");
-      __ Push(scope_->GetScopeInfo());
+      AsmPushHandle(scope_->GetScopeInfo());
       PushFunctionArgumentForContextAllocation();
-      __ CallRuntime(Runtime::kHiddenPushBlockContext, 2);
+      AsmCallRuntime(Runtime::kHiddenPushBlockContext, 2);
 
       // Replace the context stored in the frame.
       StoreToFrameField(StandardFrameConstants::kContextOffset,
@@ -1088,9 +1099,9 @@ void FullCodeGenerator::VisitBlock(Block* stmt) {
 void FullCodeGenerator::VisitModuleStatement(ModuleStatement* stmt) {
   Comment cmnt(masm_, "[ Module context");
 
-  __ Push(Smi::FromInt(stmt->proxy()->interface()->Index()));
-  __ Push(Smi::FromInt(0));
-  __ CallRuntime(Runtime::kHiddenPushModuleContext, 2);
+  AsmPushSmi(Smi::FromInt(stmt->proxy()->interface()->Index()));
+  AsmPushSmi(Smi::FromInt(0));
+  AsmCallRuntime(Runtime::kHiddenPushModuleContext, 2);
   StoreToFrameField(
       StandardFrameConstants::kContextOffset, context_register());
 
@@ -1125,18 +1136,20 @@ void FullCodeGenerator::VisitIfStatement(IfStatement* stmt) {
 
   if (stmt->HasElseStatement()) {
     VisitForControl(stmt->condition(), &then_part, &else_part, &then_part);
-    PrepareForBailoutForId(stmt->ThenId(), NO_REGISTERS);
+    StackHeightWrapper if_stack_height = CurrentStackHeight();
     __ bind(&then_part);
+    PrepareForBailoutForId(stmt->ThenId(), NO_REGISTERS);
     Visit(stmt->then_statement());
     __ jmp(&done);
 
-    PrepareForBailoutForId(stmt->ElseId(), NO_REGISTERS);
     __ bind(&else_part);
+    SetStackHeight(if_stack_height);
+    PrepareForBailoutForId(stmt->ElseId(), NO_REGISTERS);
     Visit(stmt->else_statement());
   } else {
     VisitForControl(stmt->condition(), &then_part, &done, &then_part);
-    PrepareForBailoutForId(stmt->ThenId(), NO_REGISTERS);
     __ bind(&then_part);
+    PrepareForBailoutForId(stmt->ThenId(), NO_REGISTERS);
     Visit(stmt->then_statement());
 
     PrepareForBailoutForId(stmt->ElseId(), NO_REGISTERS);
@@ -1150,6 +1163,7 @@ void FullCodeGenerator::VisitContinueStatement(ContinueStatement* stmt) {
   Comment cmnt(masm_,  "[ ContinueStatement");
   SetStatementPosition(stmt);
   NestedStatement* current = nesting_stack_;
+  StackHeightWrapper original_stack_height = CurrentStackHeight();
   int stack_depth = 0;
   int context_length = 0;
   // When continuing, we clobber the unpredictable value in the accumulator
@@ -1160,7 +1174,7 @@ void FullCodeGenerator::VisitContinueStatement(ContinueStatement* stmt) {
   while (!current->IsContinueTarget(stmt->target())) {
     current = current->Exit(&stack_depth, &context_length);
   }
-  __ Drop(stack_depth);
+  AsmDrop(stack_depth);
   if (context_length > 0) {
     while (context_length > 0) {
       LoadContextField(context_register(), Context::PREVIOUS_INDEX);
@@ -1171,6 +1185,7 @@ void FullCodeGenerator::VisitContinueStatement(ContinueStatement* stmt) {
   }
 
   __ jmp(current->AsIteration()->continue_label());
+  SetStackHeight(original_stack_height);
 }
 
 
@@ -1178,6 +1193,7 @@ void FullCodeGenerator::VisitBreakStatement(BreakStatement* stmt) {
   Comment cmnt(masm_,  "[ BreakStatement");
   SetStatementPosition(stmt);
   NestedStatement* current = nesting_stack_;
+  StackHeightWrapper original_stack_height = CurrentStackHeight();
   int stack_depth = 0;
   int context_length = 0;
   // When breaking, we clobber the unpredictable value in the accumulator
@@ -1188,7 +1204,7 @@ void FullCodeGenerator::VisitBreakStatement(BreakStatement* stmt) {
   while (!current->IsBreakTarget(stmt->target())) {
     current = current->Exit(&stack_depth, &context_length);
   }
-  __ Drop(stack_depth);
+  AsmDrop(stack_depth);
   if (context_length > 0) {
     while (context_length > 0) {
       LoadContextField(context_register(), Context::PREVIOUS_INDEX);
@@ -1199,6 +1215,7 @@ void FullCodeGenerator::VisitBreakStatement(BreakStatement* stmt) {
   }
 
   __ jmp(current->AsBreakable()->break_label());
+  SetStackHeight(original_stack_height);
 }
 
 
@@ -1209,7 +1226,7 @@ void FullCodeGenerator::EmitUnwindBeforeReturn() {
   while (current != NULL) {
     current = current->Exit(&stack_depth, &context_length);
   }
-  __ Drop(stack_depth);
+  AsmDrop(stack_depth);
 }
 
 
@@ -1218,8 +1235,11 @@ void FullCodeGenerator::VisitReturnStatement(ReturnStatement* stmt) {
   SetStatementPosition(stmt);
   Expression* expr = stmt->expression();
   VisitForAccumulatorValue(expr);
+  StackHeightWrapper previous_stack_height = CurrentStackHeight();
   EmitUnwindBeforeReturn();
   EmitReturnSequence();
+  // Reset the expected stack height
+  SetStackHeight(previous_stack_height);
 }
 
 
@@ -1229,7 +1249,7 @@ void FullCodeGenerator::VisitWithStatement(WithStatement* stmt) {
 
   VisitForStackValue(stmt->expression());
   PushFunctionArgumentForContextAllocation();
-  __ CallRuntime(Runtime::kHiddenPushWithContext, 2);
+  AsmCallRuntime(Runtime::kHiddenPushWithContext, 2);
   StoreToFrameField(StandardFrameConstants::kContextOffset, context_register());
 
   Scope* saved_scope = scope();
@@ -1268,13 +1288,13 @@ void FullCodeGenerator::VisitDoWhileStatement(DoWhileStatement* stmt) {
                   &book_keeping);
 
   // Check stack before looping.
-  PrepareForBailoutForId(stmt->BackEdgeId(), NO_REGISTERS);
   __ bind(&book_keeping);
+  PrepareForBailoutForId(stmt->BackEdgeId(), NO_REGISTERS);
   EmitBackEdgeBookkeeping(stmt, &body);
   __ jmp(&body);
 
-  PrepareForBailoutForId(stmt->ExitId(), NO_REGISTERS);
   __ bind(loop_statement.break_label());
+  PrepareForBailoutForId(stmt->ExitId(), NO_REGISTERS);
   decrement_loop_depth();
 }
 
@@ -1289,8 +1309,8 @@ void FullCodeGenerator::VisitWhileStatement(WhileStatement* stmt) {
   // Emit the test at the bottom of the loop.
   __ jmp(&test);
 
-  PrepareForBailoutForId(stmt->BodyId(), NO_REGISTERS);
   __ bind(&body);
+  PrepareForBailoutForId(stmt->BodyId(), NO_REGISTERS);
   Visit(stmt->body());
 
   // Emit the statement position here as this is where the while
@@ -1307,8 +1327,8 @@ void FullCodeGenerator::VisitWhileStatement(WhileStatement* stmt) {
                   loop_statement.break_label(),
                   loop_statement.break_label());
 
-  PrepareForBailoutForId(stmt->ExitId(), NO_REGISTERS);
   __ bind(loop_statement.break_label());
+  PrepareForBailoutForId(stmt->ExitId(), NO_REGISTERS);
   decrement_loop_depth();
 }
 
@@ -1330,12 +1350,12 @@ void FullCodeGenerator::VisitForStatement(ForStatement* stmt) {
   // Emit the test at the bottom of the loop (even if empty).
   __ jmp(&test);
 
-  PrepareForBailoutForId(stmt->BodyId(), NO_REGISTERS);
   __ bind(&body);
+  PrepareForBailoutForId(stmt->BodyId(), NO_REGISTERS);
   Visit(stmt->body());
 
-  PrepareForBailoutForId(stmt->ContinueId(), NO_REGISTERS);
   __ bind(loop_statement.continue_label());
+  PrepareForBailoutForId(stmt->ContinueId(), NO_REGISTERS);
   if (stmt->next() != NULL) {
     Visit(stmt->next());
   }
@@ -1357,8 +1377,8 @@ void FullCodeGenerator::VisitForStatement(ForStatement* stmt) {
     __ jmp(&body);
   }
 
-  PrepareForBailoutForId(stmt->ExitId(), NO_REGISTERS);
   __ bind(loop_statement.break_label());
+  PrepareForBailoutForId(stmt->ExitId(), NO_REGISTERS);
   decrement_loop_depth();
 }
 
@@ -1379,10 +1399,10 @@ void FullCodeGenerator::VisitTryCatchStatement(TryCatchStatement* stmt) {
   // Exception handler code, the exception is in the result register.
   // Extend the context before executing the catch block.
   { Comment cmnt(masm_, "[ Extend catch context");
-    __ Push(stmt->variable()->name());
-    __ Push(result_register());
+    AsmPushHandle(stmt->variable()->name());
+    AsmPush(result_register());
     PushFunctionArgumentForContextAllocation();
-    __ CallRuntime(Runtime::kHiddenPushCatchContext, 3);
+    AsmCallRuntime(Runtime::kHiddenPushCatchContext, 3);
     StoreToFrameField(StandardFrameConstants::kContextOffset,
                       context_register());
   }
@@ -1401,11 +1421,11 @@ void FullCodeGenerator::VisitTryCatchStatement(TryCatchStatement* stmt) {
 
   // Try block code. Sets up the exception handler chain.
   __ bind(&try_entry);
-  __ PushTryHandler(StackHandler::CATCH, stmt->index());
+  AsmPushTryHandler(StackHandler::CATCH, stmt->index());
   { TryCatch try_body(this);
     Visit(stmt->try_block());
   }
-  __ PopTryHandler();
+  AsmPopTryHandler();
   __ bind(&exit);
 }
 
@@ -1445,11 +1465,13 @@ void FullCodeGenerator::VisitTryFinallyStatement(TryFinallyStatement* stmt) {
   // preserved by the finally block.  Call the finally block and then
   // rethrow the exception if it returns.
   __ Call(&finally_entry);
-  __ Push(result_register());
-  __ CallRuntime(Runtime::kHiddenReThrow, 1);
+  AsmPush(result_register());
+  AsmCallRuntime(Runtime::kHiddenReThrow, 1);
 
   // Finally block implementation.
   __ bind(&finally_entry);
+  // The return address is on the stack -> update the height
+  UpdateStackHeight(1);
   EnterFinallyBlock();
   { Finally finally_body(this);
     Visit(stmt->finally_block());
@@ -1458,11 +1480,11 @@ void FullCodeGenerator::VisitTryFinallyStatement(TryFinallyStatement* stmt) {
 
   // Set up try handler.
   __ bind(&try_entry);
-  __ PushTryHandler(StackHandler::FINALLY, stmt->index());
+  AsmPushTryHandler(StackHandler::FINALLY, stmt->index());
   { TryFinally try_body(this, &finally_entry);
     Visit(stmt->try_block());
   }
-  __ PopTryHandler();
+  AsmPopTryHandler();
   // Execute the finally block on the way out.  Clobber the unpredictable
   // value in the result register with one that's safe for GC because the
   // finally block will unconditionally preserve the result register on the
@@ -1490,9 +1512,10 @@ void FullCodeGenerator::VisitConditional(Conditional* expr) {
   Comment cmnt(masm_, "[ Conditional");
   Label true_case, false_case, done;
   VisitForControl(expr->condition(), &true_case, &false_case, &true_case);
+  StackHeightWrapper if_stack_height = CurrentStackHeight();
 
-  PrepareForBailoutForId(expr->ThenId(), NO_REGISTERS);
   __ bind(&true_case);
+  PrepareForBailoutForId(expr->ThenId(), NO_REGISTERS);
   SetExpressionPosition(expr->then_expression());
   if (context()->IsTest()) {
     const TestContext* for_test = TestContext::cast(context());
@@ -1505,8 +1528,9 @@ void FullCodeGenerator::VisitConditional(Conditional* expr) {
     __ jmp(&done);
   }
 
-  PrepareForBailoutForId(expr->ElseId(), NO_REGISTERS);
   __ bind(&false_case);
+  SetStackHeight(if_stack_height);
+  PrepareForBailoutForId(expr->ElseId(), NO_REGISTERS);
   SetExpressionPosition(expr->else_expression());
   VisitInDuplicateContext(expr->else_expression());
   // If control flow falls through Visit, merge it with true case here.
@@ -1572,8 +1596,12 @@ void FullCodeGenerator::VisitNativeFunctionLiteral(
 void FullCodeGenerator::VisitThrow(Throw* expr) {
   Comment cmnt(masm_, "[ Throw");
   VisitForStackValue(expr->exception());
-  __ CallRuntime(Runtime::kHiddenThrow, 1);
-  // Never returns here.
+  AsmCallRuntime(Runtime::kHiddenThrow, 1);
+  // Never returns here. Update stack height so that we do not confuse the
+  // stack height checker.
+  if (context() != NULL && !context()->IsEffect()) {
+    UpdateStackHeight(1);
+  }
 }
 
 
@@ -1581,8 +1609,8 @@ FullCodeGenerator::NestedStatement* FullCodeGenerator::TryCatch::Exit(
     int* stack_depth,
     int* context_length) {
   // The macros used here must preserve the result register.
-  __ Drop(*stack_depth);
-  __ PopTryHandler();
+  codegen()->AsmDrop(*stack_depth);
+  codegen()->AsmPopTryHandler();
   *stack_depth = 0;
   return previous_;
 }