Make global eval faster by lazily computing its call position.

src/objects.cc

Index: src/objects.cc
diff --git a/src/objects.cc b/src/objects.cc
index 5a6286593eacb53c32adbec9ffa5e6ed0731a69f..be76d127c0f42598dc2886f0d155b56c2e9546b7 100644
--- a/src/objects.cc
+++ b/src/objects.cc
@@ -12,9 +12,9 @@
 
 #include "src/accessors.h"
 #include "src/allocation-site-scopes.h"
-#include "src/api.h"
 #include "src/api-arguments.h"
 #include "src/api-natives.h"
+#include "src/api.h"
 #include "src/base/bits.h"
 #include "src/base/utils/random-number-generator.h"
 #include "src/bootstrapper.h"
@@ -30,6 +30,7 @@
 #include "src/field-index-inl.h"
 #include "src/field-index.h"
 #include "src/field-type.h"
+#include "src/frames-inl.h"
 #include "src/full-codegen/full-codegen.h"
 #include "src/ic/ic.h"
 #include "src/identity-map.h"
@@ -13000,6 +13001,45 @@ void Oddball::Initialize(Isolate* isolate, Handle<Oddball> oddball,
   oddball->set_kind(kind);
 }
 
+void Script::SetEvalOrigin(Handle<Script> script,
+                           Handle<SharedFunctionInfo> outer_info,
+                           int eval_position) {
+  if (eval_position == RelocInfo::kNoPosition) {
+    // If the position is missing, attempt to get the code offset from the
+    // current activation.  Do not translate the code offset into source
+    // position, but store it as negative value for lazy translation.
+    StackTraceFrameIterator it(script->GetIsolate());
+    if (!it.done() && it.is_javascript()) {
+      FrameSummary summary = FrameSummary::GetFirst(it.javascript_frame());
+      script->set_eval_from_shared(summary.function()->shared());
+      script->set_eval_from_position(-summary.code_offset());
+      return;
+    }
+    eval_position = 0;
+  }
+  script->set_eval_from_shared(*outer_info);
+  script->set_eval_from_position(eval_position);
+}
+
+int Script::GetEvalPosition() {
+  DisallowHeapAllocation no_gc;
+  DCHECK(compilation_type() == Script::COMPILATION_TYPE_EVAL);
+  int position = eval_from_position();
+  if (position < 0) {
+    // Due to laziness, the position may not have been translated from code
+    // offset yet, which would be encoded as negative integer. In that case,
+    // translate and set the position.
+    if (eval_from_shared()->IsUndefined()) {
+      position = 0;
+    } else {
+      SharedFunctionInfo* shared = SharedFunctionInfo::cast(eval_from_shared());
+      position = shared->abstract_code()->SourcePosition(-position);
+    }
+    DCHECK(position >= 0);
+    set_eval_from_position(position);
+  }
+  return position;
+}
 
 void Script::InitLineEnds(Handle<Script> script) {
   if (!script->line_ends()->IsUndefined()) return;