[stubs] Ensure CSA_ASSERT and CSA_SLOW_ASSERT do not produce unused instructions in release mode.

src/builtins/builtins-regexp.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/builtins/builtins-utils.h"
 #include "src/builtins/builtins.h"
 
 #include "src/code-factory.h"
 #include "src/regexp/jsregexp.h"
 #include "src/regexp/regexp-utils.h"
@@ skipping 1659 matching lines @@
               a->LoadFixedArrayElement(res_elems, next_i, 0, mode);
 
           Node* const new_match_start = a->SmiSub(next_elem, elem);
           var_match_start.Bind(new_match_start);
           a->Goto(&loop_epilogue);
         }
       }
 
       a->Bind(&if_isstring);
       {
-        a->Assert(a->IsStringInstanceType(a->LoadInstanceType(elem)));
+        a->CSA_ASSERT(a->IsStringInstanceType(a->LoadInstanceType(elem)));
 
         Callable call_callable = CodeFactory::Call(isolate);
         Node* const replacement_obj =
             a->CallJS(call_callable, context, replace_callable, undefined, elem,
                       var_match_start.value(), subject_string);
 
         Node* const replacement_str = a->ToString(context, replacement_obj);
         a->StoreFixedArrayElement(res_elems, i, replacement_str);
 
         Node* const elem_length = a->LoadStringLength(elem);
@@ skipping 317 matching lines @@
   a->Bind(&if_matched);
   {
     Node* result = ConstructNewResultFromMatchInfo(isolate, a, context,
                                                    match_indices, string);
     a->Return(result);
   }
 }
 
 }  // namespace internal
 }  // namespace v8