[turbofan] Remove --turbo-loop-stackcheck flag.

src/compiler/ast-graph-builder.cc

 // Copyright 2014 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/compiler/ast-graph-builder.h"
 
 #include "src/ast/compile-time-value.h"
 #include "src/ast/scopes.h"
 #include "src/compilation-info.h"
 #include "src/compiler.h"
@@ skipping 2210 matching lines @@
 void AstGraphBuilder::VisitIfNotNull(Statement* stmt) {
   if (stmt == nullptr) return;
   Visit(stmt);
 }
 
 
 void AstGraphBuilder::VisitIterationBody(IterationStatement* stmt,
                                          LoopBuilder* loop,
                                          BailoutId stack_check_id) {
   ControlScopeForIteration scope(this, stmt, loop);
-  if (FLAG_turbo_loop_stackcheck || !info()->shared_info()->asm_function()) {
-    Node* node = NewNode(javascript()->StackCheck());
-    PrepareFrameState(node, stack_check_id);
-  }
+  Node* node = NewNode(javascript()->StackCheck());
+  PrepareFrameState(node, stack_check_id);
   Visit(stmt->body());
 }
 
 
 void AstGraphBuilder::VisitDelete(UnaryOperation* expr) {
   Node* value;
   if (expr->expression()->IsVariableProxy()) {
     // Delete of an unqualified identifier is disallowed in strict mode but
     // "delete this" is allowed.
     Variable* variable = expr->expression()->AsVariableProxy()->var();
@@ skipping 1057 matching lines @@
     float invocation_frequency, LoopAssignmentAnalysis* loop_assignment,
     SourcePositionTable* source_positions, int inlining_id)
     : AstGraphBuilder(local_zone, info, jsgraph, invocation_frequency,
                       loop_assignment),
       source_positions_(source_positions),
       start_position_(info->shared_info()->start_position(), inlining_id) {}
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8