Experimental: introduce factory functions for the FrameElement type....

src/virtual-frame-ia32.cc

Index: src/virtual-frame-ia32.cc
===================================================================
--- src/virtual-frame-ia32.cc	(revision 980)
+++ src/virtual-frame-ia32.cc	(working copy)
@@ -97,9 +97,8 @@
       local_count_(0),
       stack_pointer_(parameter_count_ + 1),  // 0-based index of TOS.
       frame_pointer_(kIllegalIndex) {
-  FrameElement memory_element;
   for (int i = 0; i < parameter_count_ + 2; i++) {
-    elements_.Add(memory_element);
+    elements_.Add(FrameElement::MemoryElement());
   }
 }
 
@@ -130,7 +129,7 @@
   ASSERT(stack_pointer_ == elements_.length() - 1);
 
   for (int i = 0; i < count; i++) {
-    elements_.Add(FrameElement());
+    elements_.Add(FrameElement::MemoryElement());
   }
   stack_pointer_ += count;
 }
@@ -252,8 +251,7 @@
   }
   SyncElementAt(index);
   // The element is now in memory.
-  FrameElement memory_element;
-  elements_[index] = memory_element;
+  elements_[index] = FrameElement::MemoryElement();
 }
 
 
@@ -372,8 +370,10 @@
   // bottom up.  (NB: Currently when spilling registers that are
   // multiply referenced, it is the lowermost occurrence that gets to
   // stay in the register.)
+
+  // The elements of new_elements are initially invalid.
   FrameElement* new_elements = new FrameElement[elements_.length()];
-  FrameElement memory_element;
+  FrameElement memory_element = FrameElement::MemoryElement();
   for (int i = elements_.length() - 1; i >= 0; i--) {
     FrameElement element = elements_[i];
     if (element.is_constant() ||
@@ -389,8 +389,8 @@
         if (reg.is(no_reg)) {
           new_elements[i] = memory_element;
         } else {
-          FrameElement register_element(reg, FrameElement::NOT_SYNCED);
-          new_elements[i] = register_element;
+          new_elements[i] =
+              FrameElement::RegisterElement(reg, FrameElement::NOT_SYNCED);
         }
       }
 
@@ -670,7 +670,8 @@
     // use pushes to allocate and initialize the locals.
     SyncRange(stack_pointer_ + 1, elements_.length());
     Handle<Object> undefined = Factory::undefined_value();
-    FrameElement initial_value(undefined, FrameElement::SYNCED);
+    FrameElement initial_value =
+        FrameElement::ConstantElement(undefined, FrameElement::SYNCED);
     Register temp = cgen_->allocator()->Allocate();
     __ Set(temp, Immediate(undefined));
     for (int i = 0; i < count; i++) {
@@ -696,7 +697,8 @@
     // register location.
     Register temp = cgen_->allocator()->Allocate();
     ASSERT(!temp.is(no_reg));
-    FrameElement new_element(temp, FrameElement::NOT_SYNCED);
+    FrameElement new_element
+        = FrameElement::RegisterElement(temp, FrameElement::NOT_SYNCED);
     Use(temp);
     elements_[index] = new_element;
     Use(temp);
@@ -881,7 +883,7 @@
 
 void VirtualFrame::EmitPush(Register reg) {
   ASSERT(stack_pointer_ == elements_.length() - 1);
-  elements_.Add(FrameElement());
+  elements_.Add(FrameElement::MemoryElement());
   stack_pointer_++;
   __ push(reg);
 }
@@ -889,7 +891,7 @@
 
 void VirtualFrame::EmitPush(Operand operand) {
   ASSERT(stack_pointer_ == elements_.length() - 1);
-  elements_.Add(FrameElement());
+  elements_.Add(FrameElement::MemoryElement());
   stack_pointer_++;
   __ push(operand);
 }
@@ -897,23 +899,22 @@
 
 void VirtualFrame::EmitPush(Immediate immediate) {
   ASSERT(stack_pointer_ == elements_.length() - 1);
-  FrameElement memory_element;
-  elements_.Add(memory_element);
+  elements_.Add(FrameElement::MemoryElement());
   stack_pointer_++;
   __ push(immediate);
 }
 
 
 void VirtualFrame::Push(Register reg) {
-  FrameElement register_element(reg, FrameElement::NOT_SYNCED);
   Use(reg);
-  elements_.Add(register_element);
+  elements_.Add(FrameElement::RegisterElement(reg,
+                                              FrameElement::NOT_SYNCED));
 }
 
 
 void VirtualFrame::Push(Handle<Object> value) {
-  FrameElement constant_element(value, FrameElement::NOT_SYNCED);
-  elements_.Add(constant_element);
+  elements_.Add(FrameElement::ConstantElement(value,
+                                              FrameElement::NOT_SYNCED));
 }