Remove a brittle assertion from Turbofan lazy deoptimization handling.

src/compiler/x64/code-generator-x64.cc

Index: src/compiler/x64/code-generator-x64.cc
diff --git a/src/compiler/x64/code-generator-x64.cc b/src/compiler/x64/code-generator-x64.cc
index 9f278ad8980f1aa59978d6bfa2f001bb1001cb92..f407fa5387cc0e47fed1dc2409004024eee8ac76 100644
--- a/src/compiler/x64/code-generator-x64.cc
+++ b/src/compiler/x64/code-generator-x64.cc
@@ -982,20 +982,6 @@ void CodeGenerator::AddNopForSmiCodeInlining() { __ nop(); }
 
 #undef __
 
-#ifdef DEBUG
-
-// Checks whether the code between start_pc and end_pc is a no-op.
-bool CodeGenerator::IsNopForSmiCodeInlining(Handle<Code> code, int start_pc,
-                                            int end_pc) {
-  if (start_pc + 1 != end_pc) {
-    return false;
-  }
-  return *(code->instruction_start() + start_pc) ==
-         v8::internal::Assembler::kNopByte;
-}
-
-#endif
-
 }  // namespace internal
 }  // namespace compiler
 }  // namespace v8