[turbofan] Remove Instruction::IsControl() and Instruction::MarkAsControl()

src/compiler/x64/instruction-selector-x64.cc

Index: src/compiler/x64/instruction-selector-x64.cc
diff --git a/src/compiler/x64/instruction-selector-x64.cc b/src/compiler/x64/instruction-selector-x64.cc
index f5f1264aa50500fbca5faf3bc9c7b906b329861f..bb55baa98709b2e651c37440d4c545cb02530a2f 100644
--- a/src/compiler/x64/instruction-selector-x64.cc
+++ b/src/compiler/x64/instruction-selector-x64.cc
@@ -351,9 +351,8 @@ static void VisitBinop(InstructionSelector* selector, Node* node,
   DCHECK_GE(arraysize(inputs), input_count);
   DCHECK_GE(arraysize(outputs), output_count);
 
-  Instruction* instr = selector->Emit(cont->Encode(opcode), output_count,
-                                      outputs, input_count, inputs);
-  if (cont->IsBranch()) instr->MarkAsControl();
+  selector->Emit(cont->Encode(opcode), output_count, outputs, input_count,
+                 inputs);
 }
 
 
@@ -1033,8 +1032,7 @@ void VisitCompare(InstructionSelector* selector, InstructionCode opcode,
   opcode = cont->Encode(opcode);
   if (cont->IsBranch()) {
     selector->Emit(opcode, g.NoOutput(), left, right,
-                   g.Label(cont->true_block()),
-                   g.Label(cont->false_block()))->MarkAsControl();
+                   g.Label(cont->true_block()), g.Label(cont->false_block()));
   } else {
     DCHECK(cont->IsSet());
     selector->Emit(opcode, g.DefineAsRegister(cont->result()), left, right);
@@ -1089,7 +1087,7 @@ void VisitWord64Compare(InstructionSelector* selector, Node* node,
       InstructionCode opcode = cont->Encode(kX64StackCheck);
       if (cont->IsBranch()) {
         selector->Emit(opcode, g.NoOutput(), g.Label(cont->true_block()),
-                       g.Label(cont->false_block()))->MarkAsControl();
+                       g.Label(cont->false_block()));
       } else {
         DCHECK(cont->IsSet());
         selector->Emit(opcode, g.DefineAsRegister(cont->result()));
@@ -1265,8 +1263,7 @@ void InstructionSelector::VisitSwitch(Node* node, BasicBlock* default_branch,
       DCHECK_LT(value + 2, input_count);
       inputs[value + 2] = g.Label(branch);
     }
-    Emit(kArchTableSwitch, 0, nullptr, input_count, inputs, 0, nullptr)
-        ->MarkAsControl();
+    Emit(kArchTableSwitch, 0, nullptr, input_count, inputs, 0, nullptr);
     return;
   }
 
@@ -1281,8 +1278,7 @@ void InstructionSelector::VisitSwitch(Node* node, BasicBlock* default_branch,
     inputs[index * 2 + 2 + 0] = g.TempImmediate(value);
     inputs[index * 2 + 2 + 1] = g.Label(branch);
   }
-  Emit(kArchLookupSwitch, 0, nullptr, input_count, inputs, 0, nullptr)
-      ->MarkAsControl();
+  Emit(kArchLookupSwitch, 0, nullptr, input_count, inputs, 0, nullptr);
 }