Fix issue 265 by handling extra statement state on the frame based on...

src/codegen-arm.cc

Index: src/codegen-arm.cc
===================================================================
--- src/codegen-arm.cc	(revision 1481)
+++ src/codegen-arm.cc	(working copy)
@@ -83,7 +83,6 @@
       allocator_(NULL),
       cc_reg_(al),
       state_(NULL),
-      break_stack_height_(0),
       function_return_is_shadowed_(false),
       in_spilled_code_(false) {
 }
@@ -107,8 +106,6 @@
   ASSERT(frame_ == NULL);
   frame_ = new VirtualFrame(this);
   cc_reg_ = al;
-  function_return_.Initialize(this, JumpTarget::BIDIRECTIONAL);
-  function_return_is_shadowed_ = false;
   set_in_spilled_code(false);
   {
     CodeGenState state(this);
@@ -133,6 +130,10 @@
 
     // Allocate space for locals and initialize them.
     frame_->AllocateStackSlots(scope_->num_stack_slots());
+    // Initialize the function return target after the locals are set
+    // up, because it needs the expected frame height from the frame.
+    function_return_.Initialize(this, JumpTarget::BIDIRECTIONAL);
+    function_return_is_shadowed_ = false;
 
     VirtualFrame::SpilledScope spilled_scope(this);
     if (scope_->num_heap_slots() > 0) {
@@ -1127,7 +1128,6 @@
   VirtualFrame::SpilledScope spilled_scope(this);
   Comment cmnt(masm_, "[ Block");
   CodeForStatementPosition(node);
-  node->set_break_stack_height(break_stack_height_);
   node->break_target()->Initialize(this);
   VisitStatementsAndSpill(node->statements());
   if (node->break_target()->is_linked()) {
@@ -1341,18 +1341,10 @@
 }
 
 
-void CodeGenerator::CleanStack(int num_bytes) {
-  VirtualFrame::SpilledScope spilled_scope(this);
-  ASSERT(num_bytes % kPointerSize == 0);
-  frame_->Drop(num_bytes / kPointerSize);
-}
-
-
 void CodeGenerator::VisitContinueStatement(ContinueStatement* node) {
   VirtualFrame::SpilledScope spilled_scope(this);
   Comment cmnt(masm_, "[ ContinueStatement");
   CodeForStatementPosition(node);
-  CleanStack(break_stack_height_ - node->target()->break_stack_height());
   node->target()->continue_target()->Jump();
 }
 
@@ -1361,7 +1353,6 @@
   VirtualFrame::SpilledScope spilled_scope(this);
   Comment cmnt(masm_, "[ BreakStatement");
   CodeForStatementPosition(node);
-  CleanStack(break_stack_height_ - node->target()->break_stack_height());
   node->target()->break_target()->Jump();
 }
 
@@ -1521,7 +1512,6 @@
   VirtualFrame::SpilledScope spilled_scope(this);
   Comment cmnt(masm_, "[ SwitchStatement");
   CodeForStatementPosition(node);
-  node->set_break_stack_height(break_stack_height_);
   node->break_target()->Initialize(this);
 
   LoadAndSpill(node->tag());
@@ -1615,7 +1605,6 @@
   VirtualFrame::SpilledScope spilled_scope(this);
   Comment cmnt(masm_, "[ LoopStatement");
   CodeForStatementPosition(node);
-  node->set_break_stack_height(break_stack_height_);
   node->break_target()->Initialize(this);
 
   // Simple condition analysis.  ALWAYS_TRUE and ALWAYS_FALSE represent a
@@ -1805,15 +1794,6 @@
   Comment cmnt(masm_, "[ ForInStatement");
   CodeForStatementPosition(node);
 
-  // We keep stuff on the stack while the body is executing.
-  // Record it, so that a break/continue crossing this statement
-  // can restore the stack.
-  const int kForInStackSize = 5 * kPointerSize;
-  break_stack_height_ += kForInStackSize;
-  node->set_break_stack_height(break_stack_height_);
-  node->break_target()->Initialize(this);
-  node->continue_target()->Initialize(this);
-
   JumpTarget primitive(this);
   JumpTarget jsobject(this);
   JumpTarget fixed_array(this);
@@ -1902,6 +1882,11 @@
   // sp[2] : array or enum cache
   // sp[3] : 0 or map
   // sp[4] : enumerable
+  // Grab the current frame's height for the break and continue
+  // targets only after all the state is pushed on the frame.
+  node->break_target()->Initialize(this);
+  node->continue_target()->Initialize(this);
+
   __ ldr(r0, frame_->ElementAt(0));  // load the current count
   __ ldr(r1, frame_->ElementAt(1));  // load the length
   __ cmp(r0, Operand(r1));  // compare to the array length
@@ -1986,7 +1971,6 @@
 
   // Exit.
   exit.Bind();
-  break_stack_height_ -= kForInStackSize;
   ASSERT(frame_->height() == original_height);
 }
 
@@ -2259,16 +2243,11 @@
   frame_->EmitPush(r2);
 
   // We keep two elements on the stack - the (possibly faked) result
-  // and the state - while evaluating the finally block. Record it, so
-  // that a break/continue crossing this statement can restore the
-  // stack.
-  const int kFinallyStackSize = 2 * kPointerSize;
-  break_stack_height_ += kFinallyStackSize;
-
+  // and the state - while evaluating the finally block.
+  //
   // Generate code for the statements in the finally block.
   VisitStatementsAndSpill(node->finally_block()->statements());
 
-  break_stack_height_ -= kFinallyStackSize;
   if (has_valid_frame()) {
     JumpTarget exit(this);
     // Restore state and return value or faked TOS.