diff --git a/src/arm/lithium-arm.cc b/src/arm/lithium-arm.cc
index 72bff7850e..861ea38104 100644
--- a/src/arm/lithium-arm.cc
+++ b/src/arm/lithium-arm.cc
@@ -1667,7 +1667,7 @@ LInstruction* LChunkBuilder::DoChange(HChange* instr) {
 
 LInstruction* LChunkBuilder::DoCheckNonSmi(HCheckNonSmi* instr) {
   LOperand* value = UseRegisterAtStart(instr->value());
-  return AssignEnvironment(new LCheckSmi(value, eq));
+  return AssignEnvironment(new LCheckNonSmi(value));
 }
 
 
@@ -1688,7 +1688,7 @@ LInstruction* LChunkBuilder::DoCheckPrototypeMaps(HCheckPrototypeMaps* instr) {
 
 LInstruction* LChunkBuilder::DoCheckSmi(HCheckSmi* instr) {
   LOperand* value = UseRegisterAtStart(instr->value());
-  return AssignEnvironment(new LCheckSmi(value, ne));
+  return AssignEnvironment(new LCheckSmi(value));
 }
 
 
diff --git a/src/arm/lithium-arm.h b/src/arm/lithium-arm.h
index cb811ccd6e..a148fdbea4 100644
--- a/src/arm/lithium-arm.h
+++ b/src/arm/lithium-arm.h
@@ -69,6 +69,7 @@ class LCodeGen;
   V(CallStub)                                   \
   V(CheckFunction)                              \
   V(CheckInstanceType)                          \
+  V(CheckNonSmi)                                \
   V(CheckMap)                                   \
   V(CheckPrototypeMaps)                         \
   V(CheckSmi)                                   \
@@ -1718,20 +1719,21 @@ class LCheckPrototypeMaps: public LTemplateInstruction<0, 0, 2> {
 
 class LCheckSmi: public LTemplateInstruction<0, 1, 0> {
  public:
-  LCheckSmi(LOperand* value, Condition condition)
-      : condition_(condition) {
+  explicit LCheckSmi(LOperand* value) {
     inputs_[0] = value;
   }
 
-  Condition condition() const { return condition_; }
+  DECLARE_CONCRETE_INSTRUCTION(CheckSmi, "check-smi")
+};
 
-  virtual void CompileToNative(LCodeGen* generator);
-  virtual const char* Mnemonic() const {
-    return (condition_ == eq) ? "check-non-smi" : "check-smi";
+
+class LCheckNonSmi: public LTemplateInstruction<0, 1, 0> {
+ public:
+  explicit LCheckNonSmi(LOperand* value) {
+    inputs_[0] = value;
   }
 
- private:
-  Condition condition_;
+  DECLARE_CONCRETE_INSTRUCTION(CheckNonSmi, "check-non-smi")
 };
 
 
diff --git a/src/arm/lithium-codegen-arm.cc b/src/arm/lithium-codegen-arm.cc
index aa252f1fcf..a2d1df04ae 100644
--- a/src/arm/lithium-codegen-arm.cc
+++ b/src/arm/lithium-codegen-arm.cc
@@ -3525,9 +3525,15 @@ void LCodeGen::DoDoubleToI(LDoubleToI* instr) {
 
 void LCodeGen::DoCheckSmi(LCheckSmi* instr) {
   LOperand* input = instr->InputAt(0);
-  ASSERT(input->IsRegister());
   __ tst(ToRegister(input), Operand(kSmiTagMask));
-  DeoptimizeIf(instr->condition(), instr->environment());
+  DeoptimizeIf(ne, instr->environment());
+}
+
+
+void LCodeGen::DoCheckNonSmi(LCheckNonSmi* instr) {
+  LOperand* input = instr->InputAt(0);
+  __ tst(ToRegister(input), Operand(kSmiTagMask));
+  DeoptimizeIf(eq, instr->environment());
 }
 
 
diff --git a/src/ia32/lithium-codegen-ia32.cc b/src/ia32/lithium-codegen-ia32.cc
index 2446c576ce..95383b301f 100644
--- a/src/ia32/lithium-codegen-ia32.cc
+++ b/src/ia32/lithium-codegen-ia32.cc
@@ -3497,9 +3497,15 @@ void LCodeGen::DoDoubleToI(LDoubleToI* instr) {
 
 void LCodeGen::DoCheckSmi(LCheckSmi* instr) {
   LOperand* input = instr->InputAt(0);
-  ASSERT(input->IsRegister());
   __ test(ToRegister(input), Immediate(kSmiTagMask));
-  DeoptimizeIf(instr->condition(), instr->environment());
+  DeoptimizeIf(not_zero, instr->environment());
+}
+
+
+void LCodeGen::DoCheckNonSmi(LCheckNonSmi* instr) {
+  LOperand* input = instr->InputAt(0);
+  __ test(ToRegister(input), Immediate(kSmiTagMask));
+  DeoptimizeIf(zero, instr->environment());
 }
 
 
diff --git a/src/ia32/lithium-ia32.cc b/src/ia32/lithium-ia32.cc
index 3148ae2b24..3408451c0a 100644
--- a/src/ia32/lithium-ia32.cc
+++ b/src/ia32/lithium-ia32.cc
@@ -1683,7 +1683,7 @@ LInstruction* LChunkBuilder::DoChange(HChange* instr) {
 
 LInstruction* LChunkBuilder::DoCheckNonSmi(HCheckNonSmi* instr) {
   LOperand* value = UseRegisterAtStart(instr->value());
-  return AssignEnvironment(new LCheckSmi(value, zero));
+  return AssignEnvironment(new LCheckNonSmi(value));
 }
 
 
@@ -1704,7 +1704,7 @@ LInstruction* LChunkBuilder::DoCheckPrototypeMaps(HCheckPrototypeMaps* instr) {
 
 LInstruction* LChunkBuilder::DoCheckSmi(HCheckSmi* instr) {
   LOperand* value = UseRegisterAtStart(instr->value());
-  return AssignEnvironment(new LCheckSmi(value, not_zero));
+  return AssignEnvironment(new LCheckSmi(value));
 }
 
 
diff --git a/src/ia32/lithium-ia32.h b/src/ia32/lithium-ia32.h
index 9a07c6f2a1..3d09267499 100644
--- a/src/ia32/lithium-ia32.h
+++ b/src/ia32/lithium-ia32.h
@@ -70,6 +70,7 @@ class LCodeGen;
   V(CheckFunction)                              \
   V(CheckInstanceType)                          \
   V(CheckMap)                                   \
+  V(CheckNonSmi)                                \
   V(CheckPrototypeMaps)                         \
   V(CheckSmi)                                   \
   V(ClassOfTest)                                \
@@ -1792,20 +1793,21 @@ class LCheckPrototypeMaps: public LTemplateInstruction<0, 0, 1> {
 
 class LCheckSmi: public LTemplateInstruction<0, 1, 0> {
  public:
-  LCheckSmi(LOperand* value, Condition condition)
-      : condition_(condition) {
+  explicit LCheckSmi(LOperand* value) {
     inputs_[0] = value;
   }
 
-  Condition condition() const { return condition_; }
+  DECLARE_CONCRETE_INSTRUCTION(CheckSmi, "check-smi")
+};
 
-  virtual void CompileToNative(LCodeGen* generator);
-  virtual const char* Mnemonic() const {
-    return (condition_ == zero) ? "check-non-smi" : "check-smi";
+
+class LCheckNonSmi: public LTemplateInstruction<0, 1, 0> {
+ public:
+  explicit LCheckNonSmi(LOperand* value) {
+    inputs_[0] = value;
   }
 
- private:
-  Condition condition_;
+  DECLARE_CONCRETE_INSTRUCTION(CheckNonSmi, "check-non-smi")
 };
 
 
diff --git a/src/x64/lithium-codegen-x64.cc b/src/x64/lithium-codegen-x64.cc
index d48b871769..8809f8877c 100644
--- a/src/x64/lithium-codegen-x64.cc
+++ b/src/x64/lithium-codegen-x64.cc
@@ -3297,11 +3297,14 @@ void LCodeGen::DoDoubleToI(LDoubleToI* instr) {
 
 void LCodeGen::DoCheckSmi(LCheckSmi* instr) {
   LOperand* input = instr->InputAt(0);
-  ASSERT(input->IsRegister());
   Condition cc = masm()->CheckSmi(ToRegister(input));
-  if (instr->condition() != equal) {
-    cc = NegateCondition(cc);
-  }
+  DeoptimizeIf(NegateCondition(cc), instr->environment());
+}
+
+
+void LCodeGen::DoCheckNonSmi(LCheckNonSmi* instr) {
+  LOperand* input = instr->InputAt(0);
+  Condition cc = masm()->CheckSmi(ToRegister(input));
   DeoptimizeIf(cc, instr->environment());
 }
 
diff --git a/src/x64/lithium-x64.cc b/src/x64/lithium-x64.cc
index 99a7ace3d1..4882d79a16 100644
--- a/src/x64/lithium-x64.cc
+++ b/src/x64/lithium-x64.cc
@@ -1658,7 +1658,7 @@ LInstruction* LChunkBuilder::DoChange(HChange* instr) {
 
 LInstruction* LChunkBuilder::DoCheckNonSmi(HCheckNonSmi* instr) {
   LOperand* value = UseRegisterAtStart(instr->value());
-  return AssignEnvironment(new LCheckSmi(value, zero));
+  return AssignEnvironment(new LCheckNonSmi(value));
 }
 
 
@@ -1678,7 +1678,7 @@ LInstruction* LChunkBuilder::DoCheckPrototypeMaps(HCheckPrototypeMaps* instr) {
 
 LInstruction* LChunkBuilder::DoCheckSmi(HCheckSmi* instr) {
   LOperand* value = UseRegisterAtStart(instr->value());
-  return AssignEnvironment(new LCheckSmi(value, not_zero));
+  return AssignEnvironment(new LCheckSmi(value));
 }
 
 
diff --git a/src/x64/lithium-x64.h b/src/x64/lithium-x64.h
index 926924b5d4..b43b9aea7b 100644
--- a/src/x64/lithium-x64.h
+++ b/src/x64/lithium-x64.h
@@ -70,6 +70,7 @@ class LCodeGen;
   V(CheckFunction)                              \
   V(CheckInstanceType)                          \
   V(CheckMap)                                   \
+  V(CheckNonSmi)                                \
   V(CheckPrototypeMaps)                         \
   V(CheckSmi)                                   \
   V(ClassOfTest)                                \
@@ -1707,20 +1708,21 @@ class LCheckPrototypeMaps: public LTemplateInstruction<0, 0, 1> {
 
 class LCheckSmi: public LTemplateInstruction<0, 1, 0> {
  public:
-  LCheckSmi(LOperand* value, Condition condition)
-      : condition_(condition) {
+  explicit LCheckSmi(LOperand* value) {
     inputs_[0] = value;
   }
 
-  Condition condition() const { return condition_; }
+  DECLARE_CONCRETE_INSTRUCTION(CheckSmi, "check-smi")
+};
 
-  virtual void CompileToNative(LCodeGen* generator);
-  virtual const char* Mnemonic() const {
-    return (condition_ == zero) ? "check-non-smi" : "check-smi";
+
+class LCheckNonSmi: public LTemplateInstruction<0, 1, 0> {
+ public:
+  explicit LCheckNonSmi(LOperand* value) {
+    inputs_[0] = value;
   }
 
- private:
-  Condition condition_;
+  DECLARE_CONCRETE_INSTRUCTION(CheckNonSmi, "check-non-smi")
 };