diff --git a/compiler/optimizing/code_generator_arm.cc b/compiler/optimizing/code_generator_arm.cc
index 07c84bc..32ec535 100644
--- a/compiler/optimizing/code_generator_arm.cc
+++ b/compiler/optimizing/code_generator_arm.cc
@@ -2437,10 +2437,6 @@
   Location out = locations->Out();
   Location in = locations->InAt(0);
   switch (not_->InputAt(0)->GetType()) {
-    case Primitive::kPrimBoolean:
-      __ eor(out.AsRegister<Register>(), in.AsRegister<Register>(), ShifterOperand(1));
-      break;
-
     case Primitive::kPrimInt:
       __ mvn(out.AsRegister<Register>(), ShifterOperand(in.AsRegister<Register>()));
       break;
diff --git a/compiler/optimizing/code_generator_arm64.cc b/compiler/optimizing/code_generator_arm64.cc
index 306845b..5bbcd55 100644
--- a/compiler/optimizing/code_generator_arm64.cc
+++ b/compiler/optimizing/code_generator_arm64.cc
@@ -2269,10 +2269,6 @@
 
 void InstructionCodeGeneratorARM64::VisitNot(HNot* instruction) {
   switch (instruction->InputAt(0)->GetType()) {
-    case Primitive::kPrimBoolean:
-      __ Eor(OutputRegister(instruction), InputRegisterAt(instruction, 0), Operand(1));
-      break;
-
     case Primitive::kPrimInt:
     case Primitive::kPrimLong:
       __ Mvn(OutputRegister(instruction), InputOperandAt(instruction, 0));
diff --git a/compiler/optimizing/code_generator_x86.cc b/compiler/optimizing/code_generator_x86.cc
index 57f01e8..25a6e84 100644
--- a/compiler/optimizing/code_generator_x86.cc
+++ b/compiler/optimizing/code_generator_x86.cc
@@ -2608,10 +2608,6 @@
   Location out = locations->Out();
   DCHECK(in.Equals(out));
   switch (not_->InputAt(0)->GetType()) {
-    case Primitive::kPrimBoolean:
-      __ xorl(out.AsRegister<Register>(), Immediate(1));
-      break;
-
     case Primitive::kPrimInt:
       __ notl(out.AsRegister<Register>());
       break;
diff --git a/compiler/optimizing/code_generator_x86_64.cc b/compiler/optimizing/code_generator_x86_64.cc
index dd6861f..619ac09 100644
--- a/compiler/optimizing/code_generator_x86_64.cc
+++ b/compiler/optimizing/code_generator_x86_64.cc
@@ -2469,10 +2469,6 @@
             locations->Out().AsRegister<CpuRegister>().AsRegister());
   Location out = locations->Out();
   switch (not_->InputAt(0)->GetType()) {
-    case Primitive::kPrimBoolean:
-      __ xorq(out.AsRegister<CpuRegister>(), Immediate(1));
-      break;
-
     case Primitive::kPrimInt:
       __ notl(out.AsRegister<CpuRegister>());
       break;
diff --git a/compiler/optimizing/instruction_simplifier.cc b/compiler/optimizing/instruction_simplifier.cc
index 49ca443..63bc4ae 100644
--- a/compiler/optimizing/instruction_simplifier.cc
+++ b/compiler/optimizing/instruction_simplifier.cc
@@ -59,10 +59,9 @@
       equal->ReplaceWith(equal->InputAt(0));
       equal->GetBlock()->RemoveInstruction(equal);
     } else {
-      // Replace (bool_value == 0) with !bool_value
+      // We should replace (bool_value == 0) with !bool_value, but we unfortunately
+      // do not have such instruction.
       DCHECK_EQ(input2->AsIntConstant()->GetValue(), 0);
-      equal->GetBlock()->ReplaceAndRemoveInstructionWith(
-          equal, new (GetGraph()->GetArena()) HNot(Primitive::kPrimBoolean, input1));
     }
   }
 }