[debugger] use absolute source positions for break locations.

src/debug/debug.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/debug/debug.h"
 
 #include "src/api.h"
 #include "src/arguments.h"
 #include "src/bootstrapper.h"
 #include "src/code-stubs.h"
@@ skipping 68 matching lines @@
     : debug_info_(debug_info),
       code_offset_(code_offset),
       type_(type),
       position_(position),
       statement_position_(statement_position) {
   if (type == DEBUG_BREAK_SLOT_AT_RETURN) {
     int return_position = 0;
     SharedFunctionInfo* shared = debug_info->shared();
     if (shared->HasSourceCode()) {
       return_position =
-          std::max(shared->end_position() - shared->start_position() - 1, 0);
+          std::max(shared->end_position() - 1, shared->start_position());
     }
     // TODO(yangguo): find out why return position is wrong for liveedit.
     position_ = return_position;
-    statement_position = return_position;
+    statement_position_ = return_position;
   }
 }
 
 BreakLocation::Iterator* BreakLocation::GetIterator(
     Handle<DebugInfo> debug_info, BreakLocatorType type) {
   if (debug_info->abstract_code()->IsBytecodeArray()) {
     return new BytecodeArrayIterator(debug_info, type);
   } else {
     return new CodeIterator(debug_info, type);
   }
 }
 
 BreakLocation::Iterator::Iterator(Handle<DebugInfo> debug_info)
-    : debug_info_(debug_info),
-      break_index_(-1),
-      position_(1),
-      statement_position_(1) {}
+    : debug_info_(debug_info), break_index_(-1) {
+  position_ = debug_info->shared()->start_position();
+  statement_position_ = position_;
+}
 
 BreakLocation::CodeIterator::CodeIterator(Handle<DebugInfo> debug_info,
                                           BreakLocatorType type)
     : Iterator(debug_info),
       reloc_iterator_(debug_info->abstract_code()->GetCode(),
                       GetModeMask(type)),
       source_position_iterator_(
-          debug_info->abstract_code()->GetCode()->source_position_table()),
-      start_position_(debug_info_->shared()->start_position()) {
+          debug_info->abstract_code()->GetCode()->source_position_table()) {
   // There is at least one break location.
   DCHECK(!Done());
   Next();
 }
 
 int BreakLocation::CodeIterator::GetModeMask(BreakLocatorType type) {
   int mask = 0;
   mask |= RelocInfo::ModeMask(RelocInfo::DEBUG_BREAK_SLOT_AT_RETURN);
   mask |= RelocInfo::ModeMask(RelocInfo::DEBUG_BREAK_SLOT_AT_CALL);
   if (isolate()->is_tail_call_elimination_enabled()) {
@@ skipping 13 matching lines @@
   // Iterate through reloc info stopping at each breakable code target.
   bool first = break_index_ == -1;
 
   if (!first) reloc_iterator_.next();
   first = false;
   if (Done()) return;
 
   int offset = code_offset();
   while (!source_position_iterator_.done() &&
          source_position_iterator_.code_offset() <= offset) {
-    position_ = source_position_iterator_.source_position() - start_position_;
+    position_ = source_position_iterator_.source_position();
     if (source_position_iterator_.is_statement()) {
       statement_position_ = position_;
     }
     source_position_iterator_.Advance();
   }
 
   DCHECK(RelocInfo::IsDebugBreakSlot(rmode()) ||
          RelocInfo::IsDebuggerStatement(rmode()));
   break_index_++;
 }
@@ skipping 18 matching lines @@
   return BreakLocation(debug_info_, type, code_offset(), position(),
                        statement_position());
 }
 
 BreakLocation::BytecodeArrayIterator::BytecodeArrayIterator(
     Handle<DebugInfo> debug_info, BreakLocatorType type)
     : Iterator(debug_info),
       source_position_iterator_(debug_info->abstract_code()
                                     ->GetBytecodeArray()
                                     ->source_position_table()),
-      break_locator_type_(type),
-      start_position_(debug_info->shared()->start_position()) {
+      break_locator_type_(type) {
   // There is at least one break location.
   DCHECK(!Done());
   Next();
 }
 
 void BreakLocation::BytecodeArrayIterator::Next() {
   DisallowHeapAllocation no_gc;
   DCHECK(!Done());
   bool first = break_index_ == -1;
   while (!Done()) {
     if (!first) source_position_iterator_.Advance();
     first = false;
     if (Done()) return;
-    position_ = source_position_iterator_.source_position() - start_position_;
+    position_ = source_position_iterator_.source_position();
     if (source_position_iterator_.is_statement()) {
       statement_position_ = position_;
     }
     DCHECK(position_ >= 0);
     DCHECK(statement_position_ >= 0);
 
     enum DebugBreakType type = GetDebugBreakType();
     if (type == NOT_DEBUG_BREAK) continue;
 
     if (break_locator_type_ == ALL_BREAK_LOCATIONS) break;
@@ skipping 581 matching lines @@
 
   // Make sure the function has set up the debug info.
   Handle<SharedFunctionInfo> shared = Handle<SharedFunctionInfo>::cast(result);
   if (!EnsureDebugInfo(shared, Handle<JSFunction>::null())) {
     // Return if retrieving debug info failed.
     return false;
   }
 
   // Find position within function. The script position might be before the
   // source position of the first function.
-  int position;
   if (shared->start_position() > *source_position) {
-    position = 0;
-  } else {
-    position = *source_position - shared->start_position();
+    *source_position = shared->start_position();
   }
 
   Handle<DebugInfo> debug_info(shared->GetDebugInfo());
-  // Source positions starts with zero.
-  DCHECK(position >= 0);
 
   // Find the break point and change it.
   BreakLocation location =
-      BreakLocation::FromPosition(debug_info, position, alignment);
+      BreakLocation::FromPosition(debug_info, *source_position, alignment);
   location.SetBreakPoint(break_point_object);
 
   feature_tracker()->Track(DebugFeatureTracker::kBreakPoint);
 
-  position = (alignment == STATEMENT_ALIGNED) ? location.statement_position()
-                                              : location.position();
-
-  *source_position = position + shared->start_position();
+  *source_position = (alignment == STATEMENT_ALIGNED)
+                         ? location.statement_position()
+                         : location.position();
 
   // At least one active break point now.
   DCHECK(debug_info->GetBreakPointCount() > 0);
   return true;
 }
 
 
 void Debug::ClearBreakPoint(Handle<Object> break_point_object) {
   HandleScope scope(isolate_);
 
@@ skipping 1751 matching lines @@
 }
 
 
 void LockingCommandMessageQueue::Clear() {
   base::LockGuard<base::Mutex> lock_guard(&mutex_);
   queue_.Clear();
 }
 
 }  // namespace internal
 }  // namespace v8