Merge of source position information from kernel-sdk.

runtime/vm/object.cc

Index: runtime/vm/object.cc
diff --git a/runtime/vm/object.cc b/runtime/vm/object.cc
index ccd7f25336eb8ac0355e8d39ec991b23466daed9..0cfa413eda298e48f3058400b91f3111308433f1 100644
--- a/runtime/vm/object.cc
+++ b/runtime/vm/object.cc
@@ -8782,6 +8782,8 @@ const char* Script::GetKindAsCString() const {
       return "patch";
     case RawScript::kEvaluateTag:
       return "evaluate";
+    case RawScript::kKernelTag:
+      return "kernel";
     default:
       UNIMPLEMENTED();
   }
@@ -8804,6 +8806,10 @@ void Script::set_source(const String& value) const {
   StorePointer(&raw_ptr()->source_, value.raw());
 }
 
+void Script::set_line_starts(const Array& value) const {
+  StorePointer(&raw_ptr()->line_starts_, value.raw());
+}
+
 
 void Script::set_kind(RawScript::Kind value) const {
   StoreNonPointer(&raw_ptr()->kind_, value);
@@ -8854,10 +8860,49 @@ void Script::GetTokenLocation(TokenPosition token_pos,
                               intptr_t* token_len) const {
   ASSERT(line != NULL);
   Zone* zone = Thread::Current()->zone();
+
+  if (kind() == RawScript::kKernelTag) {
+    const Array& line_starts_array = Array::Handle(line_starts());
+    if (line_starts_array.IsNull()) {
+      // Scripts in the AOT snapshot do not have a line starts array.
+      *line = -1;
+      if (column != NULL) {
+        *column = -1;
+      }
+      if (token_len != NULL) {
+        *token_len = 1;
+      }
+      return;
+    }
+    ASSERT(line_starts_array.Length() > 0);
+    intptr_t offset = token_pos.value();
+    int min = 0;
+    int max = line_starts_array.Length() - 1;
+
+    // Binary search to find the line containing this offset.
+    Smi& smi = Smi::Handle();
+    while (min < max) {
+      int midpoint = (max - min + 1) / 2 + min;
+
+      smi ^= line_starts_array.At(midpoint);
+      if (smi.Value() > offset) {
+        max = midpoint - 1;
+      } else {
+        min = midpoint;
+      }
+    }
+    *line = min + 1;
+    smi ^= line_starts_array.At(min);
+    *column = offset - smi.Value() + 1;
+    if (token_len != NULL) {
+      *token_len = 1;
+    }
+    return;
+  }
+
   const TokenStream& tkns = TokenStream::Handle(zone, tokens());
   if (tkns.IsNull()) {
-    ASSERT((Dart::snapshot_kind() == Snapshot::kAppNoJIT) ||
-           (url() == Symbols::KernelScriptUri().raw()));
+    ASSERT((Dart::snapshot_kind() == Snapshot::kAppNoJIT));
     *line = -1;
     if (column != NULL) {
       *column = -1;
@@ -22312,7 +22357,7 @@ static intptr_t PrintOneStacktrace(Zone* zone,
   intptr_t line = -1;
   intptr_t column = -1;
   if (!script.IsNull() && token_pos.IsReal()) {
-    if (script.HasSource()) {
+    if (script.HasSource() || script.kind() == RawScript::kKernelTag) {
       script.GetTokenLocation(token_pos, &line, &column);
     } else {
       script.GetTokenLocation(token_pos, &line, NULL);