Add tracking of loop nesting to ARM code.

Review URL: http://codereview.chromium.org/1645008

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4429 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/arm/codegen-arm.cc

@@ -133,6 +133,7 @@ CodeGenerator::CodeGenerator(MacroAssembler* masm)
       allocator_(NULL),
       cc_reg_(al),
       state_(NULL),
+      loop_nesting_(0),
       function_return_is_shadowed_(false) {
 }
 
@@ -156,6 +157,11 @@ void CodeGenerator::Generate(CompilationInfo* info) {
   ASSERT(frame_ == NULL);
   frame_ = new VirtualFrame();
   cc_reg_ = al;
+
+  // Adjust for function-level loop nesting.
+  ASSERT_EQ(0, loop_nesting_);
+  loop_nesting_ = info->loop_nesting();
+
   {
     CodeGenState state(this);
 
@@ -380,6 +386,10 @@ void CodeGenerator::Generate(CompilationInfo* info) {
               masm_->InstructionsGeneratedSince(&check_exit_codesize));
   }
 
+  // Adjust for function-level loop nesting.
+  ASSERT(loop_nesting_ == info->loop_nesting());
+  loop_nesting_ = 0;
+
   // Code generation state must be reset.
   ASSERT(!has_cc());
   ASSERT(state_ == NULL);
@@ -1885,6 +1895,7 @@ void CodeGenerator::VisitDoWhileStatement(DoWhileStatement* node) {
   CodeForStatementPosition(node);
   node->break_target()->set_direction(JumpTarget::FORWARD_ONLY);
   JumpTarget body(JumpTarget::BIDIRECTIONAL);
+  IncrementLoopNesting();
 
   // Label the top of the loop for the backward CFG edge.  If the test
   // is always true we can use the continue target, and if the test is
@@ -1945,6 +1956,7 @@ void CodeGenerator::VisitDoWhileStatement(DoWhileStatement* node) {
   if (node->break_target()->is_linked()) {
     node->break_target()->Bind();
   }
+  DecrementLoopNesting();
   ASSERT(!has_valid_frame() || frame_->height() == original_height);
 }
 
@@ -1963,6 +1975,7 @@ void CodeGenerator::VisitWhileStatement(WhileStatement* node) {
   if (info == ALWAYS_FALSE) return;
 
   node->break_target()->set_direction(JumpTarget::FORWARD_ONLY);
+  IncrementLoopNesting();
 
   // Label the top of the loop with the continue target for the backward
   // CFG edge.
@@ -1994,6 +2007,7 @@ void CodeGenerator::VisitWhileStatement(WhileStatement* node) {
   if (node->break_target()->is_linked()) {
     node->break_target()->Bind();
   }
+  DecrementLoopNesting();
   ASSERT(!has_valid_frame() || frame_->height() == original_height);
 }
 
@@ -2015,6 +2029,7 @@ void CodeGenerator::VisitForStatement(ForStatement* node) {
   if (info == ALWAYS_FALSE) return;
 
   node->break_target()->set_direction(JumpTarget::FORWARD_ONLY);
+  IncrementLoopNesting();
 
   // If there is no update statement, label the top of the loop with the
   // continue target, otherwise with the loop target.
@@ -2069,6 +2084,7 @@ void CodeGenerator::VisitForStatement(ForStatement* node) {
   if (node->break_target()->is_linked()) {
     node->break_target()->Bind();
   }
+  DecrementLoopNesting();
   ASSERT(!has_valid_frame() || frame_->height() == original_height);
 }
 

src/arm/codegen-arm.h

@@ -215,8 +215,10 @@ class CodeGenerator: public AstVisitor {
   JumpTarget* true_target() const  { return state_->true_target(); }
   JumpTarget* false_target() const  { return state_->false_target(); }
 
-  // We don't track loop nesting level on ARM yet.
-  int loop_nesting() const { return 0; }
+  // Track loop nesting level.
+  int loop_nesting() const { return loop_nesting_; }
+  void IncrementLoopNesting() { loop_nesting_++; }
+  void DecrementLoopNesting() { loop_nesting_--; }
 
   // Node visitors.
   void VisitStatements(ZoneList<Statement*>* statements);
@@ -284,6 +286,7 @@ class CodeGenerator: public AstVisitor {
   void LoadFromSlot(Slot* slot, TypeofState typeof_state);
   // Store the value on top of the stack to a slot.
   void StoreToSlot(Slot* slot, InitState init_state);
+
   // Load a keyed property, leaving it in r0.  The receiver and key are
   // passed on the stack, and remain there.
   void EmitKeyedLoad(bool is_global);
@@ -458,6 +461,7 @@ class CodeGenerator: public AstVisitor {
   RegisterAllocator* allocator_;
   Condition cc_reg_;
   CodeGenState* state_;
+  int loop_nesting_;
 
   // Jump targets
   BreakTarget function_return_;

src/ia32/codegen-ia32.cc

@@ -140,7 +140,8 @@ void CodeGenerator::Generate(CompilationInfo* info) {
   set_in_spilled_code(false);
 
   // Adjust for function-level loop nesting.
-  loop_nesting_ += info->loop_nesting();
+  ASSERT_EQ(0, loop_nesting_);
+  loop_nesting_ = info->loop_nesting();
 
   JumpTarget::set_compiling_deferred_code(false);
 
@@ -333,7 +334,8 @@ void CodeGenerator::Generate(CompilationInfo* info) {
   }
 
   // Adjust for function-level loop nesting.
-  loop_nesting_ -= info->loop_nesting();
+  ASSERT_EQ(info->loop_nesting(), loop_nesting_);
+  loop_nesting_ = 0;
 
   // Code generation state must be reset.
   ASSERT(state_ == NULL);

src/x64/codegen-x64.cc

@@ -290,6 +290,7 @@ void CodeGenerator::Generate(CompilationInfo* info) {
   set_in_spilled_code(false);
 
   // Adjust for function-level loop nesting.
+  ASSERT_EQ(0, loop_nesting_);
   loop_nesting_ += info->loop_nesting();
 
   JumpTarget::set_compiling_deferred_code(false);
@@ -483,11 +484,11 @@ void CodeGenerator::Generate(CompilationInfo* info) {
   }
 
   // Adjust for function-level loop nesting.
-  loop_nesting_ -= info->loop_nesting();
+  ASSERT_EQ(loop_nesting_, info->loop_nesting());
+  loop_nesting_ = 0;
 
   // Code generation state must be reset.
   ASSERT(state_ == NULL);
-  ASSERT(loop_nesting() == 0);
   ASSERT(!function_return_is_shadowed_);
   function_return_.Unuse();
   DeleteFrame();