Add assertions to FrameSummary and Code::SourcePosition.

src/objects.cc

 // Copyright 2015 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/objects.h"
 
 #include <cmath>
 #include <iomanip>
 #include <sstream>
 
@@ skipping 14039 matching lines @@
       // same distance as the current candidate and the position is higher then
       // this position is the new candidate.
       if ((dist < distance) ||
           (dist == distance && pos > position)) {
         position = pos;
         distance = dist;
       }
     }
     it.next();
   }
+  DCHECK(kind() == FUNCTION || is_optimized_code() && is_turbofanned() ||
+         is_wasm_code() || position == RelocInfo::kNoPosition);
   return position;
 }
 
 
 // Same as Code::SourcePosition above except it only looks for statement
 // positions.
 int Code::SourceStatementPosition(int code_offset) {
   // First find the position as close as possible using all position
   // information.
   int position = SourcePosition(code_offset);
@@ skipping 5684 matching lines @@
   if (cell->value() != *new_value) {
     cell->set_value(*new_value);
     Isolate* isolate = cell->GetIsolate();
     cell->dependent_code()->DeoptimizeDependentCodeGroup(
         isolate, DependentCode::kPropertyCellChangedGroup);
   }
 }
 
 }  // namespace internal
 }  // namespace v8