diff --git a/compatibility_matrices/Android.mk b/compatibility_matrices/Android.mk
index 2a01480..e876b3d 100644
--- a/compatibility_matrices/Android.mk
+++ b/compatibility_matrices/Android.mk
@@ -16,123 +16,78 @@
 
 LOCAL_PATH := $(call my-dir)
 
+BUILD_FRAMEWORK_COMPATIBILITY_MATRIX := $(LOCAL_PATH)/compatibility_matrix.mk
+
+# Clear potential input variables to BUILD_FRAMEWORK_COMPATIBILITY_MATRIX
+LOCAL_ADD_VBMETA_VERSION :=
+LOCAL_ASSEMBLE_VINTF_ENV_VARS :=
+LOCAL_ASSEMBLE_VINTF_FLAGS :=
+LOCAL_KERNEL_VERSIONS :=
+LOCAL_GEN_FILE_DEPENDENCIES :=
+
 # Install all compatibility_matrix.*.xml to /system/etc/vintf
 
+
 include $(CLEAR_VARS)
-LOCAL_MODULE := framework_compatibility_matrix.legacy.xml
 LOCAL_MODULE_STEM := compatibility_matrix.legacy.xml
 LOCAL_SRC_FILES := $(LOCAL_MODULE_STEM)
-LOCAL_MODULE_CLASS := ETC
-LOCAL_MODULE_PATH := $(TARGET_OUT)/etc/vintf
-include $(BUILD_PREBUILT)
+LOCAL_KERNEL_VERSIONS := 3.18 4.4 4.9
+include $(BUILD_FRAMEWORK_COMPATIBILITY_MATRIX)
 
 include $(CLEAR_VARS)
-LOCAL_MODULE := framework_compatibility_matrix.1.xml
 LOCAL_MODULE_STEM := compatibility_matrix.1.xml
 LOCAL_SRC_FILES := $(LOCAL_MODULE_STEM)
-LOCAL_MODULE_CLASS := ETC
-LOCAL_MODULE_PATH := $(TARGET_OUT)/etc/vintf
-include $(BUILD_PREBUILT)
+LOCAL_KERNEL_VERSIONS := 3.18 4.4 4.9
+include $(BUILD_FRAMEWORK_COMPATIBILITY_MATRIX)
 
 include $(CLEAR_VARS)
-LOCAL_MODULE := framework_compatibility_matrix.2.xml
 LOCAL_MODULE_STEM := compatibility_matrix.2.xml
 LOCAL_SRC_FILES := $(LOCAL_MODULE_STEM)
-LOCAL_MODULE_CLASS := ETC
-LOCAL_MODULE_PATH := $(TARGET_OUT)/etc/vintf
-include $(BUILD_PREBUILT)
+LOCAL_KERNEL_VERSIONS := 3.18 4.4 4.9
+include $(BUILD_FRAMEWORK_COMPATIBILITY_MATRIX)
+
+# TODO(b/72409164): STOPSHIP: update kernel version requirements
 
 include $(CLEAR_VARS)
-LOCAL_MODULE := framework_compatibility_matrix.current.xml
 LOCAL_MODULE_STEM := compatibility_matrix.current.xml
 LOCAL_SRC_FILES := $(LOCAL_MODULE_STEM)
-LOCAL_MODULE_CLASS := ETC
-LOCAL_MODULE_PATH := $(TARGET_OUT)/etc/vintf
-include $(BUILD_PREBUILT)
+LOCAL_KERNEL_VERSIONS := 4.4 4.9
+include $(BUILD_FRAMEWORK_COMPATIBILITY_MATRIX)
 
-# Framework Compatibility Matrix without HALs
+# Framework Compatibility Matrix (common to all FCM versions)
+
 include $(CLEAR_VARS)
-LOCAL_MODULE        := framework_compatibility_matrix.empty.xml
-LOCAL_MODULE_STEM   := compatibility_matrix.empty.xml
-LOCAL_MODULE_CLASS  := ETC
-LOCAL_MODULE_PATH   := $(TARGET_OUT)/etc/vintf
+LOCAL_MODULE_STEM := compatibility_matrix.empty.xml
+LOCAL_SRC_FILES := $(LOCAL_MODULE_STEM)
+LOCAL_ADD_VBMETA_VERSION := true
+LOCAL_ASSEMBLE_VINTF_ENV_VARS := \
+	POLICYVERS \
+	BOARD_SEPOLICY_VERS
 
-GEN := $(local-generated-sources-dir)/$(LOCAL_MODULE_STEM)
-
-$(GEN): PRIVATE_FLAGS :=
-
-ifeq (true,$(BOARD_AVB_ENABLE))
-$(GEN): $(AVBTOOL)
-# INTERNAL_AVB_SYSTEM_SIGNING_ARGS consists of BOARD_AVB_SYSTEM_KEY_PATH and
-# BOARD_AVB_SYSTEM_ALGORITHM. We should add the dependency of key path, which
-# is a file, here.
-$(GEN): $(BOARD_AVB_SYSTEM_KEY_PATH)
-# Use deferred assignment (=) instead of immediate assignment (:=).
-# Otherwise, cannot get INTERNAL_AVB_SYSTEM_SIGNING_ARGS.
-$(GEN): FRAMEWORK_VBMETA_VERSION = $$("$(AVBTOOL)" add_hashtree_footer \
-                           --print_required_libavb_version \
-                           $(INTERNAL_AVB_SYSTEM_SIGNING_ARGS) \
-                           $(BOARD_AVB_SYSTEM_ADD_HASHTREE_FOOTER_ARGS))
-else
-$(GEN): FRAMEWORK_VBMETA_VERSION := 0.0
-endif
-
-# Specify kernel versions that the current framework supports. These versions,
-# along with kernel configurations, are written to the framework compatibility
-# matrix.
-$(GEN): KERNEL_VERSIONS := 3.18 4.4 4.9
-
-# Specify the location of android-base*.cfg files.
-$(GEN): KERNEL_CONFIG_DATA := kernel/configs
-
-$(GEN): $(foreach version,$(KERNEL_VERSIONS),\
-	$(wildcard $(KERNEL_CONFIG_DATA)/android-$(version)/android-base*.cfg))
-$(GEN): PRIVATE_FLAGS += $(foreach version,$(KERNEL_VERSIONS),\
-	--kernel=$(version):$(call normalize-path-list,\
-		$(wildcard $(KERNEL_CONFIG_DATA)/android-$(version)/android-base*.cfg)))
-
-$(GEN): $(LOCAL_PATH)/compatibility_matrix.empty.xml $(HOST_OUT_EXECUTABLES)/assemble_vintf
-	POLICYVERS=$(POLICYVERS) \
-		BOARD_SEPOLICY_VERS=$(BOARD_SEPOLICY_VERS) \
-		FRAMEWORK_VBMETA_VERSION=$(FRAMEWORK_VBMETA_VERSION) \
-		$(HOST_OUT_EXECUTABLES)/assemble_vintf \
-		-i $< -o $@ $(PRIVATE_FLAGS)
-LOCAL_PREBUILT_MODULE_FILE := $(GEN)
-include $(BUILD_PREBUILT)
+include $(BUILD_FRAMEWORK_COMPATIBILITY_MATRIX)
 
 # Framework Compatibility Matrix
-include $(CLEAR_VARS)
-LOCAL_MODULE        := framework_compatibility_matrix.xml
-LOCAL_MODULE_STEM   := compatibility_matrix.xml
-LOCAL_MODULE_CLASS  := ETC
-LOCAL_MODULE_PATH   := $(TARGET_OUT)
 
+include $(CLEAR_VARS)
+LOCAL_MODULE := framework_compatibility_matrix.xml
+LOCAL_MODULE_STEM := compatibility_matrix.xml
+LOCAL_MODULE_PATH := $(TARGET_OUT)
 LOCAL_REQUIRED_MODULES := \
     framework_compatibility_matrix.legacy.xml \
     framework_compatibility_matrix.1.xml \
     framework_compatibility_matrix.2.xml \
     framework_compatibility_matrix.current.xml \
     framework_compatibility_matrix.empty.xml
-
-GEN := $(local-generated-sources-dir)/compatibility_matrix.xml
-
-$(GEN): PRIVATE_FLAGS :=
+LOCAL_GENERATED_SOURCES := $(call module-installed-files,$(LOCAL_REQUIRED_MODULES))
 
 ifdef BUILT_VENDOR_MANIFEST
-$(GEN): $(BUILT_VENDOR_MANIFEST)
-$(GEN): PRIVATE_FLAGS += -c "$(BUILT_VENDOR_MANIFEST)"
+LOCAL_GEN_FILE_DEPENDENCIES += $(BUILT_VENDOR_MANIFEST)
+LOCAL_ASSEMBLE_VINTF_FLAGS += -c "$(BUILT_VENDOR_MANIFEST)"
 endif
 
-MATRIX_SRC_FILES := $(call module-installed-files,$(LOCAL_REQUIRED_MODULES))
-$(GEN): PRIVATE_MATRIX_SRC_FILES := $(MATRIX_SRC_FILES)
-$(GEN): $(MATRIX_SRC_FILES) $(HOST_OUT_EXECUTABLES)/assemble_vintf
-	PRODUCT_ENFORCE_VINTF_MANIFEST=$(PRODUCT_ENFORCE_VINTF_MANIFEST) \
-		$(HOST_OUT_EXECUTABLES)/assemble_vintf \
-		-i $(call normalize-path-list,$(PRIVATE_MATRIX_SRC_FILES)) \
-		-o $@ $(PRIVATE_FLAGS)
+LOCAL_ASSEMBLE_VINTF_ENV_VARS := PRODUCT_ENFORCE_VINTF_MANIFEST
 
-MATRIX_SRC_FILES :=
-
-LOCAL_PREBUILT_MODULE_FILE := $(GEN)
-include $(BUILD_PREBUILT)
+include $(BUILD_FRAMEWORK_COMPATIBILITY_MATRIX)
 BUILT_SYSTEM_COMPATIBILITY_MATRIX := $(LOCAL_BUILT_MODULE)
+
+BUILD_FRAMEWORK_COMPATIBILITY_MATRIX :=
diff --git a/compatibility_matrices/compatibility_matrix.mk b/compatibility_matrices/compatibility_matrix.mk
new file mode 100644
index 0000000..90713d4
--- /dev/null
+++ b/compatibility_matrices/compatibility_matrix.mk
@@ -0,0 +1,87 @@
+#
+# Copyright (C) 2018 The Android Open Source Project
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+ifndef LOCAL_MODULE_STEM
+$(error LOCAL_MODULE_STEM must be defined.)
+endif
+
+LOCAL_MODULE := framework_$(LOCAL_MODULE_STEM)
+LOCAL_MODULE_CLASS := ETC
+
+ifndef LOCAL_MODULE_PATH
+LOCAL_MODULE_PATH := $(TARGET_OUT)/etc/vintf
+endif
+
+GEN := $(local-generated-sources-dir)/$(LOCAL_MODULE_STEM)
+
+$(GEN): PRIVATE_ENV_VARS := $(LOCAL_ASSEMBLE_VINTF_ENV_VARS)
+$(GEN): PRIVATE_FLAGS := $(LOCAL_ASSEMBLE_VINTF_FLAGS)
+
+$(GEN): $(LOCAL_GEN_FILE_DEPENDENCIES)
+
+ifeq (true,$(strip $(LOCAL_ADD_VBMETA_VERSION)))
+ifeq (true,$(BOARD_AVB_ENABLE))
+$(GEN): $(AVBTOOL)
+# INTERNAL_AVB_SYSTEM_SIGNING_ARGS consists of BOARD_AVB_SYSTEM_KEY_PATH and
+# BOARD_AVB_SYSTEM_ALGORITHM. We should add the dependency of key path, which
+# is a file, here.
+$(GEN): $(BOARD_AVB_SYSTEM_KEY_PATH)
+# Use deferred assignment (=) instead of immediate assignment (:=).
+# Otherwise, cannot get INTERNAL_AVB_SYSTEM_SIGNING_ARGS.
+$(GEN): FRAMEWORK_VBMETA_VERSION = $$("$(AVBTOOL)" add_hashtree_footer \
+                           --print_required_libavb_version \
+                           $(INTERNAL_AVB_SYSTEM_SIGNING_ARGS) \
+                           $(BOARD_AVB_SYSTEM_ADD_HASHTREE_FOOTER_ARGS))
+else
+$(GEN): FRAMEWORK_VBMETA_VERSION := 0.0
+endif # BOARD_AVB_ENABLE
+$(GEN): PRIVATE_ENV_VARS += FRAMEWORK_VBMETA_VERSION
+endif # LOCAL_ADD_VBMETA_VERSION
+
+ifneq (,$(strip $(LOCAL_KERNEL_VERSIONS)))
+$(GEN): PRIVATE_KERNEL_CONFIG_DATA := kernel/configs
+$(GEN): PRIVATE_KERNEL_VERSIONS := $(LOCAL_KERNEL_VERSIONS)
+$(GEN): $(foreach version,$(PRIVATE_KERNEL_VERSIONS),\
+    $(wildcard $(PRIVATE_KERNEL_CONFIG_DATA)/android-$(version)/android-base*.cfg))
+$(GEN): PRIVATE_FLAGS += $(foreach version,$(PRIVATE_KERNEL_VERSIONS),\
+    --kernel=$(version):$(call normalize-path-list,\
+        $(wildcard $(PRIVATE_KERNEL_CONFIG_DATA)/android-$(version)/android-base*.cfg)))
+endif
+
+my_matrix_src_files := \
+	$(addprefix $(LOCAL_PATH)/,$(LOCAL_SRC_FILES)) \
+	$(LOCAL_GENERATED_SOURCES)
+
+$(GEN): PRIVATE_SRC_FILES := $(my_matrix_src_files)
+$(GEN): $(my_matrix_src_files) $(HOST_OUT_EXECUTABLES)/assemble_vintf
+	$(foreach varname,$(PRIVATE_ENV_VARS),$(varname)=$($(varname))) \
+		$(HOST_OUT_EXECUTABLES)/assemble_vintf \
+		-i $(call normalize-path-list,$(PRIVATE_SRC_FILES)) \
+		-o $@ \
+		$(PRIVATE_FLAGS)
+
+LOCAL_PREBUILT_MODULE_FILE := $(GEN)
+LOCAL_SRC_FILES :=
+LOCAL_GENERATED_SOURCES :=
+
+LOCAL_ADD_VBMETA_VERSION :=
+LOCAL_ASSEMBLE_VINTF_ENV_VARS :=
+LOCAL_ASSEMBLE_VINTF_FLAGS :=
+LOCAL_KERNEL_VERSIONS :=
+LOCAL_GEN_FILE_DEPENDENCIES :=
+my_matrix_src_files :=
+
+include $(BUILD_PREBUILT)