[turbofan] Relax dependencies due to deopt during instruction scheduling.

src/compiler/instruction-scheduler.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/compiler/instruction-scheduler.h"
 
 #include "src/base/adapters.h"
 #include "src/base/utils/random-number-generator.h"
 
 namespace v8 {
@@ skipping 118 matching lines @@
   } else if (IsFixedRegisterParameter(instr)) {
     if (last_live_in_reg_marker_ != nullptr) {
       last_live_in_reg_marker_->AddSuccessor(new_node);
     }
     last_live_in_reg_marker_ = new_node;
   } else {
     if (last_live_in_reg_marker_ != nullptr) {
       last_live_in_reg_marker_->AddSuccessor(new_node);
     }
 
-    // Make sure that new instructions are not scheduled before the last
-    // deoptimization point.
-    if (last_deopt_ != nullptr) {
+    // Make sure that instructions are not scheduled before the last
+    // deoptimization point when they depend on it.
+    if ((last_deopt_ != nullptr) && DependsOnDeoptimization(instr)) {
       last_deopt_->AddSuccessor(new_node);
     }
 
     // Instructions with side effects and memory operations can't be
     // reordered with respect to each other.
     if (HasSideEffect(instr)) {
       if (last_side_effect_instr_ != nullptr) {
         last_side_effect_instr_->AddSuccessor(new_node);
       }
       for (ScheduleGraphNode* load : pending_loads_) {
@@ skipping 203 matching lines @@
       }
     }
 
     node->set_total_latency(max_latency + node->latency());
   }
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8