diff --git a/android/register.go b/android/register.go
index b48d3d1..d5aa1a5 100644
--- a/android/register.go
+++ b/android/register.go
@@ -127,6 +127,12 @@
 	RegisterModuleType(name string, factory ModuleFactory)
 	RegisterSingletonType(name string, factory SingletonFactory)
 	PreArchMutators(f RegisterMutatorFunc)
+
+	// Register pre arch mutators that are hard coded into mutator.go.
+	//
+	// Only registers mutators for testing, is a noop on the InitRegistrationContext.
+	HardCodedPreArchMutators(f RegisterMutatorFunc)
+
 	PreDepsMutators(f RegisterMutatorFunc)
 	PostDepsMutators(f RegisterMutatorFunc)
 }
@@ -180,6 +186,10 @@
 	PreArchMutators(f)
 }
 
+func (ctx *initRegistrationContext) HardCodedPreArchMutators(f RegisterMutatorFunc) {
+	// Nothing to do as the mutators are hard code in preArch in mutator.go
+}
+
 func (ctx *initRegistrationContext) PreDepsMutators(f RegisterMutatorFunc) {
 	PreDepsMutators(f)
 }
diff --git a/android/testing.go b/android/testing.go
index 6663728..c07af7f 100644
--- a/android/testing.go
+++ b/android/testing.go
@@ -59,6 +59,11 @@
 	ctx.preArch = append(ctx.preArch, f)
 }
 
+func (ctx *TestContext) HardCodedPreArchMutators(f RegisterMutatorFunc) {
+	// Register mutator function as normal for testing.
+	ctx.PreArchMutators(f)
+}
+
 func (ctx *TestContext) PreDepsMutators(f RegisterMutatorFunc) {
 	ctx.preDeps = append(ctx.preDeps, f)
 }