diff --git a/core/Makefile b/core/Makefile
index d39f9de..30ad4b6 100644
--- a/core/Makefile
+++ b/core/Makefile
@@ -5198,7 +5198,6 @@
 	$(ALL_DEFAULT_INSTALLED_MODULES) \
 	$(INSTALLED_RAMDISK_TARGET) \
 	$(ALL_DOCS) \
-	$(TARGET_OUT_COMMON_INTERMEDIATES)/PACKAGING/api-stubs-docs_annotations.zip \
 	$(ALL_SDK_FILES)
 endif
 
diff --git a/core/dex_preopt.mk b/core/dex_preopt.mk
index 55eeec6..20b4051 100644
--- a/core/dex_preopt.mk
+++ b/core/dex_preopt.mk
@@ -18,9 +18,35 @@
 ALL_DEFAULT_INSTALLED_MODULES += $(call copy-many-files,$(DEXPREOPT_IMAGE_PROFILE_BUILT_INSTALLED),$(PRODUCT_OUT))
 
 # Install boot images. Note that there can be multiple.
+my_boot_image_arch := TARGET_ARCH
+my_boot_image_out := $(PRODUCT_OUT)
+my_boot_image_syms := $(TARGET_OUT_UNSTRIPPED)
+my_boot_image_root := DEFAULT_DEX_PREOPT_INSTALLED_IMAGE
 DEFAULT_DEX_PREOPT_INSTALLED_IMAGE :=
-$(TARGET_2ND_ARCH_VAR_PREFIX)DEFAULT_DEX_PREOPT_INSTALLED_IMAGE :=
 $(foreach my_boot_image_name,$(DEXPREOPT_IMAGE_NAMES),$(eval include $(BUILD_SYSTEM)/dex_preopt_libart.mk))
+ifdef TARGET_2ND_ARCH
+  my_boot_image_arch := TARGET_2ND_ARCH
+  my_boot_image_root := 2ND_DEFAULT_DEX_PREOPT_INSTALLED_IMAGE
+  2ND_DEFAULT_DEX_PREOPT_INSTALLED_IMAGE :=
+  $(foreach my_boot_image_name,$(DEXPREOPT_IMAGE_NAMES),$(eval include $(BUILD_SYSTEM)/dex_preopt_libart.mk))
+endif
+# Install boot images for testing on host. We exclude framework image as it is not part of art manifest.
+my_boot_image_arch := HOST_ARCH
+my_boot_image_out := $(HOST_OUT)
+my_boot_image_syms := $(HOST_OUT)/symbols
+my_boot_image_root := HOST_BOOT_IMAGE
+HOST_BOOT_IMAGE :=
+$(foreach my_boot_image_name,art_host,$(eval include $(BUILD_SYSTEM)/dex_preopt_libart.mk))
+ifdef HOST_2ND_ARCH
+  my_boot_image_arch := HOST_2ND_ARCH
+  my_boot_image_root := 2ND_HOST_BOOT_IMAGE
+  2ND_HOST_BOOT_IMAGE :=
+  $(foreach my_boot_image_name,art_host,$(eval include $(BUILD_SYSTEM)/dex_preopt_libart.mk))
+endif
+my_boot_image_arch :=
+my_boot_image_out :=
+my_boot_image_syms :=
+my_boot_image_root :=
 
 # Build the boot.zip which contains the boot jars and their compilation output
 # We can do this only if preopt is enabled and if the product uses libart config (which sets the
diff --git a/core/dex_preopt_libart.mk b/core/dex_preopt_libart.mk
index 79d5f8c..12b29f4 100644
--- a/core/dex_preopt_libart.mk
+++ b/core/dex_preopt_libart.mk
@@ -1,45 +1,42 @@
 ####################################
 # ART boot image installation
-# Input variable:
+# Input variables:
 #   my_boot_image_name: the boot image to install
+#   my_boot_image_arch: the architecture to install (e.g. TARGET_ARCH, not expanded)
+#   my_boot_image_out:  the install directory (e.g. $(PRODUCT_OUT))
+#   my_boot_image_syms: the symbols director (e.g. $(TARGET_OUT_UNSTRIPPED))
+#   my_boot_image_root: make variable used to store installed image path
 #
 ####################################
 
-# Install primary arch vdex files into a shared location, and then symlink them to both the primary
-# and secondary arch directories.
-my_vdex_copy_pairs := $(DEXPREOPT_IMAGE_VDEX_BUILT_INSTALLED_$(my_boot_image_name)_$(TARGET_ARCH))
-my_installed := $(foreach v,$(my_vdex_copy_pairs),$(PRODUCT_OUT)$(call word-colon,2,$(v)))
+# Install $(1) to $(2) so that it is shared between architectures.
+define copy-vdex-file
+my_vdex_shared := $$(dir $$(patsubst %/,%,$$(dir $(2))))$$(notdir $(2))  # Remove the arch dir.
+ifneq ($(my_boot_image_arch),$(filter $(my_boot_image_arch), TARGET_2ND_ARCH HOST_2ND_ARCH))
+$$(my_vdex_shared): $(1)  # Copy $(1) to directory one level up (i.e. with the arch dir removed).
+	@echo "Install: $$@"
+	$$(copy-file-to-target)
+endif
+$(2): $$(my_vdex_shared)  # Create symlink at $(2) which points to the actual physical copy.
+	@echo "Symlink: $$@"
+	mkdir -p $$(dir $$@)
+	ln -sfn ../$$(notdir $$@) $$@
+my_vdex_shared :=
+endef
+
+# Same as 'copy-many-files' but it uses the vdex-specific helper above.
+define copy-vdex-files
+$(foreach v,$(1),$(eval $(call copy-vdex-file, $(call word-colon,1,$(v)), $(2)$(call word-colon,2,$(v)))))
+$(foreach v,$(1),$(2)$(call word-colon,2,$(v)))
+endef
+
+# Install the boot images compiled by Soong.
+# The first file is saved in $(my_boot_image_root) and the rest are added as it's dependencies.
+my_suffix := BUILT_INSTALLED_$(my_boot_image_name)_$($(my_boot_image_arch))
+my_installed := $(call copy-many-files,$(DEXPREOPT_IMAGE_$(my_suffix)),$(my_boot_image_out))
+my_installed += $(call copy-many-files,$(DEXPREOPT_IMAGE_UNSTRIPPED_$(my_suffix)),$(my_boot_image_syms))
+my_installed += $(call copy-vdex-files,$(DEXPREOPT_IMAGE_VDEX_$(my_suffix)),$(my_boot_image_out))
+$(my_boot_image_root) += $(firstword $(my_installed))
 $(firstword $(my_installed)): $(wordlist 2,9999,$(my_installed))
-
-my_built_vdex_dir := $(dir $(call word-colon,1,$(firstword $(my_vdex_copy_pairs))))
-my_installed_vdex_dir := $(PRODUCT_OUT)$(dir $(call word-colon,2,$(firstword $(my_vdex_copy_pairs))))
-
-$(my_installed): $(my_installed_vdex_dir)% : $(my_built_vdex_dir)%
-	@echo "Install: $@"
-	@rm -f $@
-	$(copy-file-to-target)
-	mkdir -p $(dir $@)/$(TARGET_ARCH)
-	ln -sfn ../$(notdir $@) $(dir $@)/$(TARGET_ARCH)
-ifdef TARGET_2ND_ARCH
-	mkdir -p $(dir $@)/$(TARGET_2ND_ARCH)
-	ln -sfn ../$(notdir $@) $(dir $@)/$(TARGET_2ND_ARCH)
-endif
-
-my_dexpreopt_image_extra_deps := $(firstword $(my_installed))
-
-my_2nd_arch_prefix :=
-include $(BUILD_SYSTEM)/dex_preopt_libart_boot.mk
-
-ifdef TARGET_2ND_ARCH
-  my_2nd_arch_prefix := $(TARGET_2ND_ARCH_VAR_PREFIX)
-  include $(BUILD_SYSTEM)/dex_preopt_libart_boot.mk
-endif
-
-my_2nd_arch_prefix :=
-
-
-my_vdex_copy_pairs :=
 my_installed :=
-my_built_vdex_dir :=
-my_installed_vdex_dir :=
-my_dexpreopt_image_extra_deps :=
+my_suffix :=
diff --git a/core/dex_preopt_libart_boot.mk b/core/dex_preopt_libart_boot.mk
deleted file mode 100644
index 34b8526..0000000
--- a/core/dex_preopt_libart_boot.mk
+++ /dev/null
@@ -1,25 +0,0 @@
-# Rules to install a boot image built by dexpreopt_bootjars.go
-# Input variables:
-#   my_boot_image_name: the boot image to install
-#   my_2nd_arch_prefix: indicates if this is to build for the 2nd arch.
-#   my_dexpreopt_image_extra_deps: extra dependencies to add on the installed boot.art
-
-# Install the boot images compiled by Soong
-# The first file (generally boot.art) is saved as DEFAULT_DEX_PREOPT_INSTALLED_IMAGE,
-# and the rest are added as dependencies of the first.
-
-my_installed := $(call copy-many-files,$(DEXPREOPT_IMAGE_BUILT_INSTALLED_$(my_boot_image_name)_$(TARGET_$(my_2nd_arch_prefix)ARCH)),$(PRODUCT_OUT))
-$(firstword $(my_installed)): $(wordlist 2,9999,$(my_installed))
-$(my_2nd_arch_prefix)DEFAULT_DEX_PREOPT_INSTALLED_IMAGE += $(firstword $(my_installed))
-
-# Install the unstripped boot images compiled by Soong into the symbols directory
-# The first file (generally boot.art) made a dependency of DEFAULT_DEX_PREOPT_INSTALLED_IMAGE,
-# and the rest are added as dependencies of the first.
-my_installed := $(call copy-many-files,$(DEXPREOPT_IMAGE_UNSTRIPPED_BUILT_INSTALLED_$(my_boot_image_name)_$(TARGET_$(my_2nd_arch_prefix)ARCH)),$(TARGET_OUT_UNSTRIPPED))
-$(firstword $(my_installed)): $(wordlist 2,9999,$(my_installed))
-$($(my_2nd_arch_prefix)DEFAULT_DEX_PREOPT_INSTALLED_IMAGE): $(firstword $(my_installed))
-
-$($(my_2nd_arch_prefix)DEFAULT_DEX_PREOPT_INSTALLED_IMAGE): $(my_dexpreopt_image_extra_deps)
-
-my_installed :=
-my_built_installed :=
diff --git a/tools/releasetools/ota_from_target_files.py b/tools/releasetools/ota_from_target_files.py
index 7a0d994..2126d11 100755
--- a/tools/releasetools/ota_from_target_files.py
+++ b/tools/releasetools/ota_from_target_files.py
@@ -631,7 +631,7 @@
     partition_target_info = target_info["fstab"]["/" + name]
     disable_imgdiff = (partition_source_info.fs_type == "squashfs" or
                        partition_target_info.fs_type == "squashfs")
-    return common.BlockDifference(name, partition_src, partition_tgt,
+    return common.BlockDifference(name, partition_tgt, partition_src,
                                   check_first_block,
                                   version=blockimgdiff_version,
                                   disable_imgdiff=disable_imgdiff)