Support for precise stepping in functions compiled before debugging was started (step 2)

src/compiler.cc

 // Copyright 2011 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 41 matching lines @@
 
 CompilationInfo::CompilationInfo(Handle<Script> script)
     : isolate_(script->GetIsolate()),
       flags_(0),
       function_(NULL),
       scope_(NULL),
       script_(script),
       extension_(NULL),
       pre_parse_data_(NULL),
       supports_deoptimization_(false),
-      osr_ast_id_(AstNode::kNoNumber) {
+      osr_ast_id_(AstNode::kNoNumber),
+      compiling_for_debugging_(false) {
   Initialize(NONOPT);
 }
 
 
 CompilationInfo::CompilationInfo(Handle<SharedFunctionInfo> shared_info)
     : isolate_(shared_info->GetIsolate()),
       flags_(IsLazy::encode(true)),
       function_(NULL),
       scope_(NULL),
       shared_info_(shared_info),
       script_(Handle<Script>(Script::cast(shared_info->script()))),
       extension_(NULL),
       pre_parse_data_(NULL),
       supports_deoptimization_(false),
-      osr_ast_id_(AstNode::kNoNumber) {
+      osr_ast_id_(AstNode::kNoNumber),
+      compiling_for_debugging_(false) {
   Initialize(BASE);
 }
 
 
 CompilationInfo::CompilationInfo(Handle<JSFunction> closure)
     : isolate_(closure->GetIsolate()),
       flags_(IsLazy::encode(true)),
       function_(NULL),
       scope_(NULL),
       closure_(closure),
       shared_info_(Handle<SharedFunctionInfo>(closure->shared())),
       script_(Handle<Script>(Script::cast(shared_info_->script()))),
       extension_(NULL),
       pre_parse_data_(NULL),
       supports_deoptimization_(false),
-      osr_ast_id_(AstNode::kNoNumber) {
+      osr_ast_id_(AstNode::kNoNumber),
+      compiling_for_debugging_(false) {
   Initialize(BASE);
 }
 
 
 // Disable optimization for the rest of the compilation pipeline.
 void CompilationInfo::DisableOptimization() {
   bool is_optimizable_closure =
     FLAG_optimize_closures &&
     closure_.is_null() &&
     !scope_->HasTrivialOuterContext() &&
@@ skipping 197 matching lines @@
     Handle<JSFunction> closure = info->closure();
     info->shared_info()->DisableOptimization(*closure);
   }
   // True indicates the compilation pipeline is still going, not necessarily
   // that we optimized the code.
   return true;
 }
 
 
 static bool GenerateCode(CompilationInfo* info) {
-  return V8::UseCrankshaft() ?
-    MakeCrankshaftCode(info) :
-    FullCodeGenerator::MakeCode(info);
+  if (info->CompilingForDebugging()) {

[Kevin Millikin (Chromium), 2011/09/29 10:47:35]

You could piggyback on the existing test so the control flow through here
doesn't get too complicated conditions don't get too complicated:

return V8::UseCrankshaft() && !info->CompilingForDebugging()
    ? MakeCrankshaftCode(info)
    : FullCodeGenerator::MakeCode(info);

or 

return info->CompilingForDebugging() || !V8::UseCrankshaft()
    ? FullCodeGenerator::MakeCode(info)
    : MakeCrankshaftCode(info);

[Søren Thygesen Gjesse, 2011/09/30 08:33:22]

Done.

+    return FullCodeGenerator::MakeCode(info);
+  } else {
+    return V8::UseCrankshaft() ?
+        MakeCrankshaftCode(info) :
+        FullCodeGenerator::MakeCode(info);
+  }
 }
 
 
 static bool MakeCode(CompilationInfo* info) {
   // Precondition: code has been parsed.  Postcondition: the code field in
   // the compilation info is set if compilation succeeded.
   ASSERT(info->function() != NULL);
   return Rewriter::Rewrite(info) && Scope::Analyze(info) && GenerateCode(info);
 }
 
@@ skipping 465 matching lines @@
     }
   }
 
   GDBJIT(AddCode(Handle<String>(shared->DebugName()),
                  Handle<Script>(info->script()),
                  Handle<Code>(info->code()),
                  info));
 }
 
 } }  // namespace v8::internal