diff --git a/src/compiler/effect-control-linearizer.cc b/src/compiler/effect-control-linearizer.cc
index fb850093c8..6cab5f259e 100644
--- a/src/compiler/effect-control-linearizer.cc
+++ b/src/compiler/effect-control-linearizer.cc
@@ -1281,10 +1281,7 @@ void EffectControlLinearizer::TruncateTaggedPointerToBit(
             &if_heapnumber);
 
   // Check if {value} is a BigInt.
-  Node* value_instance_type =
-      __ LoadField(AccessBuilder::ForMapInstanceType(), value_map);
-  __ GotoIf(__ Word32Equal(value_instance_type, __ Int32Constant(BIGINT_TYPE)),
-            &if_bigint);
+  __ GotoIf(__ WordEqual(value_map, __ BigIntMapConstant()), &if_bigint);
 
   // All other values that reach here are true.
   __ Goto(done, __ Int32Constant(1));
@@ -2478,10 +2475,7 @@ Node* EffectControlLinearizer::LowerObjectIsBigInt(Node* node) {
   Node* check = ObjectIsSmi(value);
   __ GotoIf(check, &if_smi);
   Node* value_map = __ LoadField(AccessBuilder::ForMap(), value);
-  Node* value_instance_type =
-      __ LoadField(AccessBuilder::ForMapInstanceType(), value_map);
-  Node* vfalse =
-      __ Word32Equal(value_instance_type, __ Uint32Constant(BIGINT_TYPE));
+  Node* vfalse = __ WordEqual(value_map, __ BigIntMapConstant());
   __ Goto(&done, vfalse);
 
   __ Bind(&if_smi);
diff --git a/src/compiler/graph-assembler.h b/src/compiler/graph-assembler.h
index c8e4517f66..eeebcd7ee5 100644
--- a/src/compiler/graph-assembler.h
+++ b/src/compiler/graph-assembler.h
@@ -92,6 +92,7 @@ namespace compiler {
   V(TrueConstant)                          \
   V(FalseConstant)                         \
   V(NullConstant)                          \
+  V(BigIntMapConstant)                     \
   V(BooleanMapConstant)                    \
   V(HeapNumberMapConstant)                 \
   V(NoContextConstant)                     \
diff --git a/src/compiler/js-graph.cc b/src/compiler/js-graph.cc
index eca30ad525..dc5746ae96 100644
--- a/src/compiler/js-graph.cc
+++ b/src/compiler/js-graph.cc
@@ -134,6 +134,8 @@ DEFINE_GETTER(AllocateInOldSpaceStubConstant,
 DEFINE_GETTER(ArrayConstructorStubConstant,
               HeapConstant(BUILTIN_CODE(isolate(), ArrayConstructorImpl)))
 
+DEFINE_GETTER(BigIntMapConstant, HeapConstant(factory()->bigint_map()))
+
 DEFINE_GETTER(BooleanMapConstant, HeapConstant(factory()->boolean_map()))
 
 DEFINE_GETTER(ToNumberBuiltinConstant,
diff --git a/src/compiler/js-graph.h b/src/compiler/js-graph.h
index 3ce87d37a6..52c618122e 100644
--- a/src/compiler/js-graph.h
+++ b/src/compiler/js-graph.h
@@ -84,6 +84,7 @@ class V8_EXPORT_PRIVATE JSGraph : public MachineGraph {
   V(AllocateInNewSpaceStubConstant) \
   V(AllocateInOldSpaceStubConstant) \
   V(ArrayConstructorStubConstant)   \
+  V(BigIntMapConstant)              \
   V(BooleanMapConstant)             \
   V(ToNumberBuiltinConstant)        \
   V(EmptyFixedArrayConstant)        \