diff --git a/core/clear_vars.mk b/core/clear_vars.mk
index a564b3c..a389915 100644
--- a/core/clear_vars.mk
+++ b/core/clear_vars.mk
@@ -98,8 +98,7 @@
 LOCAL_SDK_VERSION:=
 LOCAL_SDK_RES_VERSION:=
 LOCAL_NDK_STL_VARIANT:=
-LOCAL_NO_EMMA_INSTRUMENT:=
-LOCAL_NO_EMMA_COMPILE:=
+LOCAL_EMMA_INSTRUMENT:=
 LOCAL_PROGUARD_ENABLED:= # '',optonly,full,custom,disabled
 LOCAL_PROGUARD_FLAGS:=
 LOCAL_PROGUARD_FLAG_FILES:=
diff --git a/core/config.mk b/core/config.mk
index aa4e7f1..b35e55d 100644
--- a/core/config.mk
+++ b/core/config.mk
@@ -403,8 +403,6 @@
 # define llvm tools and global flags
 include $(BUILD_SYSTEM)/llvm_config.mk
 
-PREBUILT_IS_PRESENT := $(if $(wildcard prebuilt/Android.mk),true)
-
 # ###############################################################
 # Collect a list of the SDK versions that we could compile against
 # For use with the LOCAL_SDK_VERSION variable for include $(BUILD_PACKAGE)
diff --git a/core/java.mk b/core/java.mk
index 4d85601..9e47dc3 100644
--- a/core/java.mk
+++ b/core/java.mk
@@ -75,29 +75,8 @@
 intermediates := $(call local-intermediates-dir)
 intermediates.COMMON := $(call local-intermediates-dir,COMMON)
 
-# Emma source code coverage
-ifeq ($(EMMA_FULL_APP_INSTRUMENT),true)
-  # doing a full emma instrument here, i.e. all app packages instrumented
-  EMMA_INSTRUMENT := true
-  # do not instrument modules that are not app packages
-  ifneq ($(LOCAL_MODULE_CLASS),APPS)
-    LOCAL_NO_EMMA_INSTRUMENT := true
-    LOCAL_NO_EMMA_COMPILE := true
-  endif
-  # do not instrument modules that are marked tests
-  ifeq ($(LOCAL_MODULE_TAGS),tests)
-    LOCAL_NO_EMMA_INSTRUMENT := true
-    LOCAL_NO_EMMA_COMPILE := true
-  endif
-endif
-
-ifneq ($(EMMA_INSTRUMENT),true)
-LOCAL_NO_EMMA_INSTRUMENT := true
-LOCAL_NO_EMMA_COMPILE := true
-endif
-
 # Choose leaf name for the compiled jar file.
-ifneq ($(LOCAL_NO_EMMA_COMPILE),true)
+ifeq ($(LOCAL_EMMA_INSTRUMENT),true)
 full_classes_compiled_jar_leaf := classes-no-debug-var.jar
 built_dex_intermediate_leaf := classes-no-local.dex
 else
@@ -307,13 +286,7 @@
 	$(hide) $(ACP) -fp $< $@
 endif
 
-ifeq ($(LOCAL_IS_STATIC_JAVA_LIBRARY),true)
-# Skip adding emma instrumentation to class files if this is a static library,
-# since it will be instrumented by the package that includes it
-LOCAL_NO_EMMA_INSTRUMENT:= true
-endif
-
-ifneq ($(LOCAL_NO_EMMA_INSTRUMENT),true)
+ifeq ($(LOCAL_EMMA_INSTRUMENT),true)
 $(full_classes_emma_jar): PRIVATE_EMMA_COVERAGE_FILE := $(intermediates.COMMON)/coverage.em
 $(full_classes_emma_jar): PRIVATE_EMMA_INTERMEDIATES_DIR := $(emma_intermediates_dir)
 # module level coverage filter can be defined using LOCAL_EMMA_COVERAGE_FILTER
@@ -329,10 +302,7 @@
 # $(full_classes_emma_jar)
 $(full_classes_emma_jar): $(full_classes_jarjar_jar) | $(EMMA_JAR)
 	$(transform-classes.jar-to-emma)
-$(PRIVATE_EMMA_COVERAGE_FILE): $(full_classes_emma_jar)
 
-# tell proguard to load emma jar
-LOCAL_PROGUARD_FLAGS := $(LOCAL_PROGUARD_FLAGS) $(addprefix -libraryjars ,$(EMMA_JAR))
 else
 $(full_classes_emma_jar): $(full_classes_jarjar_jar) | $(ACP)
 	@echo Copying: $@
@@ -396,7 +366,7 @@
 # The workaround here is to build different dex file here based on emma switch
 # then later copy into classes.dex. When emma is on, dx is run with --no-locals
 # option to remove local variable information
-ifneq ($(LOCAL_NO_EMMA_COMPILE),true)
+ifeq ($(LOCAL_EMMA_INSTRUMENT),true)
 $(built_dex_intermediate): PRIVATE_DX_FLAGS += --no-locals
 endif
 $(built_dex_intermediate): $(full_classes_proguard_jar) $(DX)
diff --git a/core/java_library.mk b/core/java_library.mk
index 06cdfc4..03e069d 100644
--- a/core/java_library.mk
+++ b/core/java_library.mk
@@ -44,6 +44,16 @@
 LOCAL_DEX_PREOPT :=
 endif
 
+ifeq (true,$(EMMA_INSTRUMENT))
+ifeq (true,$(LOCAL_EMMA_INSTRUMENT))
+ifeq (true,$(EMMA_INSTRUMENT_STATIC))
+LOCAL_STATIC_JAVA_LIBRARIES += emma
+endif # LOCAL_EMMA_INSTRUMENT
+endif # EMMA_INSTRUMENT_STATIC
+else
+LOCAL_EMMA_INSTRUMENT := false
+endif # EMMA_INSTRUMENT
+
 #################################
 include $(BUILD_SYSTEM)/java.mk
 #################################
diff --git a/core/main.mk b/core/main.mk
index def9f62..eda80ed 100644
--- a/core/main.mk
+++ b/core/main.mk
@@ -218,6 +218,11 @@
 MAKECMDGOALS := $(filter-out incrementaljavac, $(MAKECMDGOALS))
 endif
 
+# EMMA_INSTRUMENT_STATIC merges the static emma library to each emma-enabled module.
+ifeq (true,$(EMMA_INSTRUMENT_STATIC))
+EMMA_INSTRUMENT := true
+endif
+
 # Bring in standard build system definitions.
 include $(BUILD_SYSTEM)/definitions.mk
 
diff --git a/core/package.mk b/core/package.mk
index a1d901e..c181ae4 100644
--- a/core/package.mk
+++ b/core/package.mk
@@ -170,6 +170,35 @@
 LOCAL_DEX_PREOPT :=
 endif
 
+ifeq (true,$(EMMA_INSTRUMENT))
+ifndef LOCAL_EMMA_INSTRUMENT
+# No emma for test apks.
+ifeq (,$(filer tests,$(LOCAL_MODULE_TAGS))$(LOCAL_INSTRUMENTATION_FOR))
+LOCAL_EMMA_INSTRUMENT := true
+endif # No test apk
+endif # LOCAL_EMMA_INSTRUMENT is not set
+else
+LOCAL_EMMA_INSTRUMENT := false
+endif # EMMA_INSTRUMENT is true
+
+ifeq (true,$(LOCAL_EMMA_INSTRUMENT))
+ifeq (true,$(EMMA_INSTRUMENT_STATIC))
+LOCAL_STATIC_JAVA_LIBRARIES += emma
+else
+ifdef LOCAL_SDK_VERSION
+ifdef TARGET_BUILD_APPS
+# In unbundled build merge the emma library into the apk.
+LOCAL_STATIC_JAVA_LIBRARIES += emma
+else
+# If build against the SDK in full build, core.jar is not used,
+# we have to use prebiult emma.jar to make Proguard happy;
+# Otherwise emma classes are included in core.jar.
+LOCAL_PROGUARD_FLAGS += -libraryjars $(EMMA_JAR)
+endif # full build
+endif # LOCAL_SDK_VERSION
+endif # EMMA_INSTRUMENT_STATIC
+endif # LOCAL_EMMA_INSTRUMENT
+
 #################################
 include $(BUILD_SYSTEM)/java.mk
 #################################