[profiler] collect more source positions when debugger is active.

src/compilation-info.cc

 // Copyright 2016 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/compilation-info.h"
 
 #include "src/api.h"
 #include "src/ast/ast.h"
 #include "src/ast/scopes.h"
+#include "src/debug/debug.h"
 #include "src/isolate.h"
 #include "src/parsing/parse-info.h"
 #include "src/source-position.h"
 
 namespace v8 {
 namespace internal {
 
 #define PARSE_INFO_GETTER(type, name)  \
   type CompilationInfo::name() const { \
     CHECK(parse_info());               \
@@ skipping 41 matching lines @@
   // compiling later on. This means that code recompiled with deoptimization
   // support won't be "equivalent" (as defined by SharedFunctionInfo::
   // EnableDeoptimizationSupport), so it will replace the old code and all
   // its type feedback. To avoid this, always compile functions in the snapshot
   // with deoptimization support.
   if (isolate_->serializer_enabled()) EnableDeoptimizationSupport();
 
   if (FLAG_function_context_specialization) MarkAsFunctionContextSpecializing();
   if (FLAG_turbo_splitting) MarkAsSplittingEnabled();
 
+  // Collect source positions for optimized code when profiling or if debugger
+  // is active, to be able to get more precise source positions at the price of
+  // more memory consumption.
   if (FLAG_trace_deopt || FLAG_trace_turbo || FLAG_trace_turbo_graph ||
-      FLAG_turbo_profiling || isolate_->is_profiling()) {
+      FLAG_turbo_profiling || isolate_->is_profiling() ||
+      isolate_->debug()->is_active()) {
     MarkAsSourcePositionsEnabled();
   }
 }
 
 CompilationInfo::CompilationInfo(Vector<const char> debug_name,
                                  Isolate* isolate, Zone* zone,
                                  Code::Flags code_flags)
     : CompilationInfo(nullptr, debug_name, code_flags, STUB, isolate, zone) {}
 
 CompilationInfo::CompilationInfo(ParseInfo* parse_info,
@@ skipping 143 matching lines @@
       inlined_function, handle(inlined_function->code()), pos));
   return id;
 }
 
 Code::Kind CompilationInfo::output_code_kind() const {
   return Code::ExtractKindFromFlags(code_flags_);
 }
 
 }  // namespace internal
 }  // namespace v8