Introduce a BreakTarget subclass of JumpTarget used to represent the...

src/jump-target.cc

 // Copyright 2009 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 19 matching lines @@
 #include "codegen.h"
 #include "jump-target.h"
 
 namespace v8 { namespace internal {
 
 // -------------------------------------------------------------------------
 // JumpTarget implementation.
 
 JumpTarget::JumpTarget(CodeGenerator* cgen, Directionality direction)
     : cgen_(cgen),
+      masm_(cgen == NULL ? NULL : cgen->masm()),
       direction_(direction),
       reaching_frames_(0),
       merge_labels_(0),
       entry_frame_(NULL),
       is_bound_(false),
       is_linked_(false) {
-  ASSERT(cgen_ != NULL);
-  masm_ = cgen_->masm();
-}
-
-
-JumpTarget::JumpTarget()
-    : cgen_(NULL),
-      masm_(NULL),
-      direction_(FORWARD_ONLY),
-      reaching_frames_(0),
-      merge_labels_(0),
-      entry_frame_(NULL),
-      is_bound_(false),
-      is_linked_(false) {
 }
 
 
-void JumpTarget::Initialize(CodeGenerator* cgen, Directionality direction) {
-  ASSERT(cgen != NULL);
-  ASSERT(cgen_ == NULL);
-  cgen_ = cgen;
-  masm_ = cgen->masm();
-  direction_ = direction;
-}
-
-
 void JumpTarget::Unuse() {
   ASSERT(!is_linked());
   entry_label_.Unuse();
   delete entry_frame_;
   entry_frame_ = NULL;
   is_bound_ = false;
   is_linked_ = false;
 }
 
 
@@ skipping 423 matching lines @@
     cgen_->frame()->Push(arg3);
   }
   Bind(mergable_elements);
   *arg3 = cgen_->frame()->Pop();
   *arg2 = cgen_->frame()->Pop();
   *arg1 = cgen_->frame()->Pop();
   *arg0 = cgen_->frame()->Pop();
 }
 
 
-void JumpTarget::CopyTo(JumpTarget* destination) {
+void JumpTarget::AddReachingFrame(VirtualFrame* frame) {
+  ASSERT(reaching_frames_.length() == merge_labels_.length());
+  Label fresh;
+  merge_labels_.Add(fresh);
+  reaching_frames_.Add(frame);
+}
+
+
+// -------------------------------------------------------------------------
+// BreakTarget implementation.
+
+BreakTarget::BreakTarget() : JumpTarget(NULL, FORWARD_ONLY) {
+}
+
+
+void BreakTarget::Initialize(CodeGenerator* cgen, Directionality direction) {
+  ASSERT(cgen != NULL);
+  ASSERT(cgen_ == NULL);
+  cgen_ = cgen;
+  masm_ = cgen->masm();
+  direction_ = direction;
+}
+
+
+void BreakTarget::CopyTo(BreakTarget* destination) {
   ASSERT(destination != NULL);
   destination->cgen_ = cgen_;
   destination->masm_ = masm_;
   destination->direction_ = direction_;
   destination->reaching_frames_.Clear();
   destination->merge_labels_.Clear();
   ASSERT(reaching_frames_.length() == merge_labels_.length());
   for (int i = 0; i < reaching_frames_.length(); i++) {
     destination->reaching_frames_.Add(reaching_frames_[i]);
     destination->merge_labels_.Add(merge_labels_[i]);
   }
   destination->entry_frame_ = entry_frame_;
   destination->entry_label_ = entry_label_;
   destination->is_bound_ = is_bound_;
   destination->is_linked_ = is_linked_;
 }
 
 
-void JumpTarget::AddReachingFrame(VirtualFrame* frame) {
-  ASSERT(reaching_frames_.length() == merge_labels_.length());
-  Label fresh;
-  merge_labels_.Add(fresh);
-  reaching_frames_.Add(frame);
-}
-
-
 // -------------------------------------------------------------------------
 // ShadowTarget implementation.
 
-ShadowTarget::ShadowTarget(JumpTarget* shadowed) {
+ShadowTarget::ShadowTarget(BreakTarget* shadowed) {
   ASSERT(shadowed != NULL);
   other_target_ = shadowed;
 
 #ifdef DEBUG
   is_shadowing_ = true;
 #endif
   // While shadowing this shadow target saves the state of the original.
   shadowed->CopyTo(this);
 
   // Setting the code generator to null prevents the shadow target from
@@ skipping 11 matching lines @@
 void ShadowTarget::StopShadowing() {
   ASSERT(is_shadowing_);
 
   // This target does not have a valid code generator yet.
   cgen_ = other_target_->code_generator();
   ASSERT(cgen_ != NULL);
   masm_ = cgen_->masm();
 
   // The states of this target, which was shadowed, and the original
   // target, which was shadowing, are swapped.
-  JumpTarget temp;
+  BreakTarget temp;
   other_target_->CopyTo(&temp);
   CopyTo(other_target_);
   temp.CopyTo(this);
   temp.Reset();  // So the destructor does not deallocate virtual frames.
 
 #ifdef DEBUG
   is_shadowing_ = false;
 #endif
 }
 
 
 } }  // namespace v8::internal