diff --git a/android/Android.bp b/android/Android.bp
index 69aa037..efa70a9 100644
--- a/android/Android.bp
+++ b/android/Android.bp
@@ -59,6 +59,7 @@
         "sandbox.go",
         "sdk.go",
         "singleton.go",
+        "singleton_module.go",
         "soong_config_modules.go",
         "test_suites.go",
         "testing.go",
@@ -95,6 +96,7 @@
         "paths_test.go",
         "prebuilt_test.go",
         "rule_builder_test.go",
+        "singleton_module_test.go",
         "soong_config_modules_test.go",
         "util_test.go",
         "variable_test.go",
diff --git a/android/config.go b/android/config.go
index ddb2de3..a7e0b67 100644
--- a/android/config.go
+++ b/android/config.go
@@ -1256,6 +1256,27 @@
 	return HasAnyPrefix(path, c.productVariables.CFIIncludePaths)
 }
 
+func (c *config) MemtagHeapDisabledForPath(path string) bool {
+	if len(c.productVariables.MemtagHeapExcludePaths) == 0 {
+		return false
+	}
+	return HasAnyPrefix(path, c.productVariables.MemtagHeapExcludePaths)
+}
+
+func (c *config) MemtagHeapAsyncEnabledForPath(path string) bool {
+	if len(c.productVariables.MemtagHeapAsyncIncludePaths) == 0 {
+		return false
+	}
+	return HasAnyPrefix(path, c.productVariables.MemtagHeapAsyncIncludePaths)
+}
+
+func (c *config) MemtagHeapSyncEnabledForPath(path string) bool {
+	if len(c.productVariables.MemtagHeapSyncIncludePaths) == 0 {
+		return false
+	}
+	return HasAnyPrefix(path, c.productVariables.MemtagHeapSyncIncludePaths)
+}
+
 func (c *config) VendorConfig(name string) VendorConfig {
 	return soongconfig.Config(c.productVariables.VendorVars[name])
 }
diff --git a/android/makevars.go b/android/makevars.go
index 546abcf..40c0ccd 100644
--- a/android/makevars.go
+++ b/android/makevars.go
@@ -134,8 +134,6 @@
 
 // SingletonMakeVarsProvider is a Singleton with an extra method to provide extra values to be exported to Make.
 type SingletonMakeVarsProvider interface {
-	Singleton
-
 	// MakeVars uses a MakeVarsContext to provide extra values to be exported to Make.
 	MakeVars(ctx MakeVarsContext)
 }
diff --git a/android/module.go b/android/module.go
index b0ad89b..17035bb 100644
--- a/android/module.go
+++ b/android/module.go
@@ -454,6 +454,7 @@
 	InstallForceOS() (*OsType, *ArchType)
 	HideFromMake()
 	IsHideFromMake() bool
+	IsSkipInstall() bool
 	MakeUninstallable()
 	ReplacedByPrebuilt()
 	IsReplacedByPrebuilt() bool
@@ -1398,6 +1399,12 @@
 	m.commonProperties.SkipInstall = true
 }
 
+// IsSkipInstall returns true if this variant is marked to not create install
+// rules when ctx.Install* are called.
+func (m *ModuleBase) IsSkipInstall() bool {
+	return m.commonProperties.SkipInstall
+}
+
 // Similar to HideFromMake, but if the AndroidMk entry would set
 // LOCAL_UNINSTALLABLE_MODULE then this variant may still output that entry
 // rather than leaving it out altogether. That happens in cases where it would
diff --git a/android/register.go b/android/register.go
index 995be0c..ca658f5 100644
--- a/android/register.go
+++ b/android/register.go
@@ -16,6 +16,7 @@
 
 import (
 	"fmt"
+	"reflect"
 
 	"github.com/google/blueprint"
 )
@@ -26,6 +27,7 @@
 }
 
 var moduleTypes []moduleType
+var moduleTypesForDocs = map[string]reflect.Value{}
 
 type singleton struct {
 	name    string
@@ -72,6 +74,16 @@
 
 func RegisterModuleType(name string, factory ModuleFactory) {
 	moduleTypes = append(moduleTypes, moduleType{name, factory})
+	RegisterModuleTypeForDocs(name, reflect.ValueOf(factory))
+}
+
+// RegisterModuleTypeForDocs associates a module type name with a reflect.Value of the factory
+// function that has documentation for the module type.  It is normally called automatically
+// by RegisterModuleType, but can be called manually after RegisterModuleType in order to
+// override the factory method used for documentation, for example if the method passed to
+// RegisterModuleType was a lambda.
+func RegisterModuleTypeForDocs(name string, factory reflect.Value) {
+	moduleTypesForDocs[name] = factory
 }
 
 func RegisterSingletonType(name string, factory SingletonFactory) {
@@ -157,12 +169,17 @@
 	return ret
 }
 
+func ModuleTypeFactoriesForDocs() map[string]reflect.Value {
+	return moduleTypesForDocs
+}
+
 // Interface for registering build components.
 //
 // Provided to allow registration of build components to be shared between the runtime
 // and test environments.
 type RegistrationContext interface {
 	RegisterModuleType(name string, factory ModuleFactory)
+	RegisterSingletonModuleType(name string, factory SingletonModuleFactory)
 	RegisterSingletonType(name string, factory SingletonFactory)
 	PreArchMutators(f RegisterMutatorFunc)
 
@@ -201,8 +218,9 @@
 var _ RegistrationContext = (*TestContext)(nil)
 
 type initRegistrationContext struct {
-	moduleTypes    map[string]ModuleFactory
-	singletonTypes map[string]SingletonFactory
+	moduleTypes        map[string]ModuleFactory
+	singletonTypes     map[string]SingletonFactory
+	moduleTypesForDocs map[string]reflect.Value
 }
 
 func (ctx *initRegistrationContext) RegisterModuleType(name string, factory ModuleFactory) {
@@ -211,6 +229,17 @@
 	}
 	ctx.moduleTypes[name] = factory
 	RegisterModuleType(name, factory)
+	RegisterModuleTypeForDocs(name, reflect.ValueOf(factory))
+}
+
+func (ctx *initRegistrationContext) RegisterSingletonModuleType(name string, factory SingletonModuleFactory) {
+	s, m := SingletonModuleFactoryAdaptor(name, factory)
+	ctx.RegisterSingletonType(name, s)
+	ctx.RegisterModuleType(name, m)
+	// Overwrite moduleTypesForDocs with the original factory instead of the lambda returned by
+	// SingletonModuleFactoryAdaptor so that docs can find the module type documentation on the
+	// factory method.
+	RegisterModuleTypeForDocs(name, reflect.ValueOf(factory))
 }
 
 func (ctx *initRegistrationContext) RegisterSingletonType(name string, factory SingletonFactory) {
diff --git a/android/singleton_module.go b/android/singleton_module.go
new file mode 100644
index 0000000..2351738
--- /dev/null
+++ b/android/singleton_module.go
@@ -0,0 +1,146 @@
+// Copyright 2020 Google Inc. All rights reserved.
+//
+// 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.
+
+package android
+
+import (
+	"fmt"
+	"sync"
+
+	"github.com/google/blueprint"
+)
+
+// A SingletonModule is halfway between a Singleton and a Module.  It has access to visiting
+// other modules via its GenerateSingletonBuildActions method, but must be defined in an Android.bp
+// file and can also be depended on like a module.  It must be used zero or one times in an
+// Android.bp file, and it can only have a single variant.
+//
+// The SingletonModule's GenerateAndroidBuildActions method will be called before any normal or
+// singleton module that depends on it, but its GenerateSingletonBuildActions method will be called
+// after all modules, in registration order with other singletons and singleton modules.
+// GenerateAndroidBuildActions and GenerateSingletonBuildActions will not be called if the
+// SingletonModule was not instantiated in an Android.bp file.
+//
+// Since the SingletonModule rules likely depend on the modules visited during
+// GenerateSingletonBuildActions, the GenerateAndroidBuildActions is unlikely to produce any
+// rules directly.  Instead, it will probably set some providers to paths that will later have rules
+// generated to produce them in GenerateSingletonBuildActions.
+//
+// The expected use case for a SingletonModule is a module that produces files that depend on all
+// modules in the tree and will be used by other modules.  For example it could produce a text
+// file that lists all modules that meet a certain criteria, and that text file could be an input
+// to another module.  Care must be taken that the ninja rules produced by the SingletonModule
+// don't produce a cycle by referencing output files of rules of modules that depend on the
+// SingletonModule.
+//
+// A SingletonModule must embed a SingletonModuleBase struct, and its factory method must be
+// registered with RegisterSingletonModuleType from an init() function.
+//
+// A SingletonModule can also implement SingletonMakeVarsProvider to export values to Make.
+type SingletonModule interface {
+	Module
+	GenerateSingletonBuildActions(SingletonContext)
+	singletonModuleBase() *SingletonModuleBase
+}
+
+// SingletonModuleBase must be embedded into implementers of the SingletonModule interface.
+type SingletonModuleBase struct {
+	ModuleBase
+
+	lock    sync.Mutex
+	bp      string
+	variant string
+}
+
+// GenerateBuildActions wraps the ModuleBase GenerateBuildActions method, verifying it was only
+// called once to prevent multiple variants of a SingletonModule.
+func (smb *SingletonModuleBase) GenerateBuildActions(ctx blueprint.ModuleContext) {
+	smb.lock.Lock()
+	if smb.variant != "" {
+		ctx.ModuleErrorf("GenerateAndroidBuildActions already called for variant %q, SingletonModules can only  have one variant", smb.variant)
+	}
+	smb.variant = ctx.ModuleSubDir()
+	smb.lock.Unlock()
+
+	smb.ModuleBase.GenerateBuildActions(ctx)
+}
+
+// InitAndroidSingletonModule must be called from the SingletonModule's factory function to
+// initialize SingletonModuleBase.
+func InitAndroidSingletonModule(sm SingletonModule) {
+	InitAndroidModule(sm)
+}
+
+// singletonModuleBase retrieves the embedded SingletonModuleBase from a SingletonModule.
+func (smb *SingletonModuleBase) singletonModuleBase() *SingletonModuleBase { return smb }
+
+// SingletonModuleFactory is a factory method that returns a SingletonModule.
+type SingletonModuleFactory func() SingletonModule
+
+// SingletonModuleFactoryAdaptor converts a SingletonModuleFactory into a SingletonFactory and a
+// ModuleFactory.
+func SingletonModuleFactoryAdaptor(name string, factory SingletonModuleFactory) (SingletonFactory, ModuleFactory) {
+	// The sm variable acts as a static holder of the only SingletonModule instance.  Calls to the
+	// returned SingletonFactory and ModuleFactory lambdas will always return the same sm value.
+	// The SingletonFactory is only expected to be called once, but the ModuleFactory may be
+	// called multiple times if the module is replaced with a clone of itself at the end of
+	// blueprint.ResolveDependencies.
+	var sm SingletonModule
+	s := func() Singleton {
+		sm = factory()
+		return &singletonModuleSingletonAdaptor{sm}
+	}
+	m := func() Module {
+		if sm == nil {
+			panic(fmt.Errorf("Singleton %q for SingletonModule was not instantiated", name))
+		}
+
+		// Check for multiple uses of a SingletonModule in a LoadHook.  Checking directly in the
+		// factory would incorrectly flag when the factory was called again when the module is
+		// replaced with a clone of itself at the end of blueprint.ResolveDependencies.
+		AddLoadHook(sm, func(ctx LoadHookContext) {
+			smb := sm.singletonModuleBase()
+			smb.lock.Lock()
+			defer smb.lock.Unlock()
+			if smb.bp != "" {
+				ctx.ModuleErrorf("Duplicate SingletonModule %q, previously used in %s", name, smb.bp)
+			}
+			smb.bp = ctx.BlueprintsFile()
+		})
+		return sm
+	}
+	return s, m
+}
+
+// singletonModuleSingletonAdaptor makes a SingletonModule into a Singleton by translating the
+// GenerateSingletonBuildActions method to Singleton.GenerateBuildActions.
+type singletonModuleSingletonAdaptor struct {
+	sm SingletonModule
+}
+
+// GenerateBuildActions calls the SingletonModule's GenerateSingletonBuildActions method, but only
+// if the module was defined in an Android.bp file.
+func (smsa *singletonModuleSingletonAdaptor) GenerateBuildActions(ctx SingletonContext) {
+	if smsa.sm.singletonModuleBase().bp != "" {
+		smsa.sm.GenerateSingletonBuildActions(ctx)
+	}
+}
+
+func (smsa *singletonModuleSingletonAdaptor) MakeVars(ctx MakeVarsContext) {
+	if smsa.sm.singletonModuleBase().bp != "" {
+		if makeVars, ok := smsa.sm.(SingletonMakeVarsProvider); ok {
+			makeVars.MakeVars(ctx)
+		}
+	}
+}
diff --git a/android/singleton_module_test.go b/android/singleton_module_test.go
new file mode 100644
index 0000000..9232eb4
--- /dev/null
+++ b/android/singleton_module_test.go
@@ -0,0 +1,149 @@
+// Copyright 2021 Google Inc. All rights reserved.
+//
+// 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.
+
+package android
+
+import (
+	"reflect"
+	"strings"
+	"testing"
+)
+
+type testSingletonModule struct {
+	SingletonModuleBase
+	ops []string
+}
+
+func (tsm *testSingletonModule) GenerateAndroidBuildActions(ctx ModuleContext) {
+	tsm.ops = append(tsm.ops, "GenerateAndroidBuildActions")
+}
+
+func (tsm *testSingletonModule) GenerateSingletonBuildActions(ctx SingletonContext) {
+	tsm.ops = append(tsm.ops, "GenerateSingletonBuildActions")
+}
+
+func (tsm *testSingletonModule) MakeVars(ctx MakeVarsContext) {
+	tsm.ops = append(tsm.ops, "MakeVars")
+}
+
+func testSingletonModuleFactory() SingletonModule {
+	tsm := &testSingletonModule{}
+	InitAndroidSingletonModule(tsm)
+	return tsm
+}
+
+func runSingletonModuleTest(bp string) (*TestContext, []error) {
+	config := TestConfig(buildDir, nil, bp, nil)
+	// Enable Kati output to test SingletonModules with MakeVars.
+	config.katiEnabled = true
+	ctx := NewTestContext(config)
+	ctx.RegisterSingletonModuleType("test_singleton_module", testSingletonModuleFactory)
+	ctx.RegisterSingletonType("makevars", makeVarsSingletonFunc)
+	ctx.Register()
+
+	_, errs := ctx.ParseBlueprintsFiles("Android.bp")
+	if len(errs) > 0 {
+		return ctx, errs
+	}
+
+	_, errs = ctx.PrepareBuildActions(config)
+	return ctx, errs
+}
+
+func TestSingletonModule(t *testing.T) {
+	bp := `
+		test_singleton_module {
+			name: "test_singleton_module",
+		}
+	`
+	ctx, errs := runSingletonModuleTest(bp)
+	if len(errs) > 0 {
+		t.Fatal(errs)
+	}
+
+	ops := ctx.ModuleForTests("test_singleton_module", "").Module().(*testSingletonModule).ops
+	wantOps := []string{"GenerateAndroidBuildActions", "GenerateSingletonBuildActions", "MakeVars"}
+	if !reflect.DeepEqual(ops, wantOps) {
+		t.Errorf("Expected operations %q, got %q", wantOps, ops)
+	}
+}
+
+func TestDuplicateSingletonModule(t *testing.T) {
+	bp := `
+		test_singleton_module {
+			name: "test_singleton_module",
+		}
+
+		test_singleton_module {
+			name: "test_singleton_module2",
+		}
+	`
+	_, errs := runSingletonModuleTest(bp)
+	if len(errs) == 0 {
+		t.Fatal("expected duplicate SingletonModule error")
+	}
+	if len(errs) != 1 || !strings.Contains(errs[0].Error(), `Duplicate SingletonModule "test_singleton_module", previously used in`) {
+		t.Fatalf("expected duplicate SingletonModule error, got %q", errs)
+	}
+}
+
+func TestUnusedSingletonModule(t *testing.T) {
+	bp := ``
+	ctx, errs := runSingletonModuleTest(bp)
+	if len(errs) > 0 {
+		t.Fatal(errs)
+	}
+
+	singleton := ctx.SingletonForTests("test_singleton_module").Singleton()
+	sm := singleton.(*singletonModuleSingletonAdaptor).sm
+	ops := sm.(*testSingletonModule).ops
+	if ops != nil {
+		t.Errorf("Expected no operations, got %q", ops)
+	}
+}
+
+func testVariantSingletonModuleMutator(ctx BottomUpMutatorContext) {
+	if _, ok := ctx.Module().(*testSingletonModule); ok {
+		ctx.CreateVariations("a", "b")
+	}
+}
+
+func TestVariantSingletonModule(t *testing.T) {
+	bp := `
+		test_singleton_module {
+			name: "test_singleton_module",
+		}
+	`
+
+	config := TestConfig(buildDir, nil, bp, nil)
+	ctx := NewTestContext(config)
+	ctx.PreDepsMutators(func(ctx RegisterMutatorsContext) {
+		ctx.BottomUp("test_singleton_module_mutator", testVariantSingletonModuleMutator)
+	})
+	ctx.RegisterSingletonModuleType("test_singleton_module", testSingletonModuleFactory)
+	ctx.Register()
+
+	_, errs := ctx.ParseBlueprintsFiles("Android.bp")
+
+	if len(errs) == 0 {
+		_, errs = ctx.PrepareBuildActions(config)
+	}
+
+	if len(errs) == 0 {
+		t.Fatal("expected duplicate SingletonModule error")
+	}
+	if len(errs) != 1 || !strings.Contains(errs[0].Error(), `GenerateAndroidBuildActions already called for variant`) {
+		t.Fatalf("expected duplicate SingletonModule error, got %q", errs)
+	}
+}
diff --git a/android/testing.go b/android/testing.go
index 6539063..a66b1e1 100644
--- a/android/testing.go
+++ b/android/testing.go
@@ -103,6 +103,12 @@
 	ctx.Context.RegisterModuleType(name, ModuleFactoryAdaptor(factory))
 }
 
+func (ctx *TestContext) RegisterSingletonModuleType(name string, factory SingletonModuleFactory) {
+	s, m := SingletonModuleFactoryAdaptor(name, factory)
+	ctx.RegisterSingletonType(name, s)
+	ctx.RegisterModuleType(name, m)
+}
+
 func (ctx *TestContext) RegisterSingletonType(name string, factory SingletonFactory) {
 	ctx.Context.RegisterSingletonType(name, SingletonFactoryAdaptor(ctx.Context, factory))
 }
diff --git a/android/variable.go b/android/variable.go
index 9786b9f..41cd337 100644
--- a/android/variable.go
+++ b/android/variable.go
@@ -260,6 +260,10 @@
 
 	DisableScudo *bool `json:",omitempty"`
 
+	MemtagHeapExcludePaths      []string `json:",omitempty"`
+	MemtagHeapAsyncIncludePaths []string `json:",omitempty"`
+	MemtagHeapSyncIncludePaths  []string `json:",omitempty"`
+
 	VendorPath    *string `json:",omitempty"`
 	OdmPath       *string `json:",omitempty"`
 	ProductPath   *string `json:",omitempty"`
diff --git a/apex/allowed_deps.txt b/apex/allowed_deps.txt
index 57b18de..c11a89c 100644
--- a/apex/allowed_deps.txt
+++ b/apex/allowed_deps.txt
@@ -486,6 +486,8 @@
 neuralnetworks_utils_hal_1_3(minSdkVersion:30)
 neuralnetworks_utils_hal_common(minSdkVersion:30)
 neuralnetworks_utils_hal_service(minSdkVersion:30)
+note_memtag_heap_async(minSdkVersion:16)
+note_memtag_heap_sync(minSdkVersion:16)
 PermissionController(minSdkVersion:28)
 permissioncontroller-statsd(minSdkVersion:current)
 philox_random(minSdkVersion:(no version))
diff --git a/apex/apex.go b/apex/apex.go
index a18e34b..5cd18ed 100644
--- a/apex/apex.go
+++ b/apex/apex.go
@@ -168,6 +168,10 @@
 	// used in tests.
 	Test_only_unsigned_payload *bool
 
+	// Whenever apex should be compressed, regardless of product flag used. Should be only
+	// used in tests.
+	Test_only_force_compression *bool
+
 	IsCoverageVariant bool `blueprint:"mutated"`
 
 	// List of sanitizer names that this APEX is enabled for
@@ -1241,6 +1245,11 @@
 	return proptools.Bool(a.properties.Test_only_unsigned_payload)
 }
 
+// See the test_only_force_compression property
+func (a *apexBundle) testOnlyShouldForceCompression() bool {
+	return proptools.Bool(a.properties.Test_only_force_compression)
+}
+
 // These functions are interfacing with cc/sanitizer.go. The entire APEX (along with all of its
 // members) can be sanitized, either forcibly, or by the global configuration. For some of the
 // sanitizers, extra dependencies can be forcibly added as well.
diff --git a/apex/builder.go b/apex/builder.go
index 106302b..bc1b566 100644
--- a/apex/builder.go
+++ b/apex/builder.go
@@ -763,9 +763,13 @@
 	})
 	a.outputFile = signedOutputFile
 
-	// Process APEX compression if enabled
+	// Process APEX compression if enabled or forced
+	if ctx.ModuleDir() != "system/apex/apexd/apexd_testdata" && a.testOnlyShouldForceCompression() {
+		ctx.PropertyErrorf("test_only_force_compression", "not available")
+		return
+	}
 	compressionEnabled := ctx.Config().CompressedApex() && proptools.BoolDefault(a.properties.Compressible, true)
-	if compressionEnabled && apexType == imageApex {
+	if apexType == imageApex && (compressionEnabled || a.testOnlyShouldForceCompression()) {
 		a.isCompressed = true
 		unsignedCompressedOutputFile := android.PathForModuleOut(ctx, a.Name()+".capex.unsigned")
 
diff --git a/cc/cc.go b/cc/cc.go
index c0c85f9..ca2bd4f 100644
--- a/cc/cc.go
+++ b/cc/cc.go
@@ -420,6 +420,7 @@
 type ModuleContextIntf interface {
 	static() bool
 	staticBinary() bool
+	testBinary() bool
 	header() bool
 	binary() bool
 	object() bool
@@ -1261,6 +1262,10 @@
 	return ctx.mod.staticBinary()
 }
 
+func (ctx *moduleContextImpl) testBinary() bool {
+	return ctx.mod.testBinary()
+}
+
 func (ctx *moduleContextImpl) header() bool {
 	return ctx.mod.Header()
 }
@@ -2961,6 +2966,15 @@
 	return false
 }
 
+func (c *Module) testBinary() bool {
+	if test, ok := c.linker.(interface {
+		testBinary() bool
+	}); ok {
+		return test.testBinary()
+	}
+	return false
+}
+
 // Header returns true if the module is a header-only variant. (See cc/library.go header()).
 func (c *Module) Header() bool {
 	if h, ok := c.linker.(interface {
diff --git a/cc/cc_test.go b/cc/cc_test.go
index 3502d5f..3399e93 100644
--- a/cc/cc_test.go
+++ b/cc/cc_test.go
@@ -738,12 +738,29 @@
 			},
 			nocrt: true,
 		}
+
+		cc_library {
+			name: "libllndk",
+			llndk_stubs: "libllndk.llndk",
+		}
+
+		llndk_library {
+			name: "libllndk.llndk",
+			symbol_file: "",
+			export_llndk_headers: ["libllndk_headers"],
+		}
+
+		llndk_headers {
+			name: "libllndk_headers",
+			export_include_dirs: ["include"],
+		}
 	`)
 
 	checkVndkOutput(t, ctx, "vndk/vndk.libraries.txt", []string{
 		"LLNDK: libc.so",
 		"LLNDK: libdl.so",
 		"LLNDK: libft2.so",
+		"LLNDK: libllndk.so",
 		"LLNDK: libm.so",
 		"VNDK-SP: libc++.so",
 		"VNDK-core: libvndk-private.so",
@@ -4461,3 +4478,138 @@
 		t.Errorf("aidl command %q does not contain %q", aidlCommand, expectedAidlFlag)
 	}
 }
+
+func checkHasImplicitDep(t *testing.T, m android.TestingModule, name string) {
+	implicits := m.Rule("ld").Implicits
+	for _, lib := range implicits {
+		if strings.Contains(lib.Rel(), name) {
+			return
+		}
+	}
+
+	t.Errorf("%q is not found in implicit deps of module %q", name, m.Module().(*Module).Name())
+}
+
+func checkDoesNotHaveImplicitDep(t *testing.T, m android.TestingModule, name string) {
+	implicits := m.Rule("ld").Implicits
+	for _, lib := range implicits {
+		if strings.Contains(lib.Rel(), name) {
+			t.Errorf("%q is found in implicit deps of module %q", name, m.Module().(*Module).Name())
+		}
+	}
+}
+
+func TestSanitizeMemtagHeap(t *testing.T) {
+	rootBp := `
+		cc_library_static {
+			name: "libstatic",
+			sanitize: { memtag_heap: true },
+		}
+
+		cc_library_shared {
+			name: "libshared",
+			sanitize: { memtag_heap: true },
+		}
+
+		cc_library {
+			name: "libboth",
+			sanitize: { memtag_heap: true },
+		}
+
+		cc_binary {
+			name: "binary",
+			shared_libs: [ "libshared" ],
+			static_libs: [ "libstatic" ],
+		}
+
+		cc_binary {
+			name: "binary_true",
+			sanitize: { memtag_heap: true },
+		}
+
+		cc_binary {
+			name: "binary_true_sync",
+			sanitize: { memtag_heap: true, diag: { memtag_heap: true }, },
+		}
+
+		cc_binary {
+			name: "binary_false",
+			sanitize: { memtag_heap: false },
+		}
+
+		cc_test {
+			name: "test",
+			gtest: false,
+		}
+
+		cc_test {
+			name: "test_true",
+			gtest: false,
+			sanitize: { memtag_heap: true },
+		}
+
+		cc_test {
+			name: "test_false",
+			gtest: false,
+			sanitize: { memtag_heap: false },
+		}
+
+		cc_test {
+			name: "test_true_async",
+			gtest: false,
+			sanitize: { memtag_heap: true, diag: { memtag_heap: false }  },
+		}
+
+		`
+
+	subdirAsyncBp := `
+		cc_binary {
+			name: "binary_async",
+		}
+		`
+
+	subdirSyncBp := `
+		cc_binary {
+			name: "binary_sync",
+		}
+		`
+
+	mockFS := map[string][]byte{
+		"subdir_async/Android.bp": []byte(subdirAsyncBp),
+		"subdir_sync/Android.bp":  []byte(subdirSyncBp),
+	}
+
+	config := TestConfig(buildDir, android.Android, nil, rootBp, mockFS)
+	config.TestProductVariables.DeviceVndkVersion = StringPtr("current")
+	config.TestProductVariables.Platform_vndk_version = StringPtr("VER")
+	config.TestProductVariables.MemtagHeapAsyncIncludePaths = []string{"subdir_async"}
+	config.TestProductVariables.MemtagHeapSyncIncludePaths = []string{"subdir_sync"}
+	ctx := CreateTestContext(config)
+	ctx.Register()
+
+	_, errs := ctx.ParseFileList(".", []string{"Android.bp", "subdir_sync/Android.bp", "subdir_async/Android.bp"})
+	android.FailIfErrored(t, errs)
+	_, errs = ctx.PrepareBuildActions(config)
+	android.FailIfErrored(t, errs)
+
+	variant := "android_arm64_armv8-a"
+	note_async := "note_memtag_heap_async"
+	note_sync := "note_memtag_heap_sync"
+	note_any := "note_memtag_"
+
+	checkDoesNotHaveImplicitDep(t, ctx.ModuleForTests("libshared", "android_arm64_armv8-a_shared"), note_any)
+	checkDoesNotHaveImplicitDep(t, ctx.ModuleForTests("libboth", "android_arm64_armv8-a_shared"), note_any)
+
+	checkDoesNotHaveImplicitDep(t, ctx.ModuleForTests("binary", variant), note_any)
+	checkHasImplicitDep(t, ctx.ModuleForTests("binary_true", variant), note_async)
+	checkHasImplicitDep(t, ctx.ModuleForTests("binary_true_sync", variant), note_sync)
+	checkDoesNotHaveImplicitDep(t, ctx.ModuleForTests("binary_false", variant), note_any)
+
+	checkHasImplicitDep(t, ctx.ModuleForTests("test", variant), note_sync)
+	checkHasImplicitDep(t, ctx.ModuleForTests("test_true", variant), note_async)
+	checkDoesNotHaveImplicitDep(t, ctx.ModuleForTests("test_false", variant), note_any)
+	checkHasImplicitDep(t, ctx.ModuleForTests("test_true_async", variant), note_async)
+
+	checkHasImplicitDep(t, ctx.ModuleForTests("binary_async", variant), note_async)
+	checkHasImplicitDep(t, ctx.ModuleForTests("binary_sync", variant), note_sync)
+}
diff --git a/cc/config/global.go b/cc/config/global.go
index fa8e0fb..d47e0ce 100644
--- a/cc/config/global.go
+++ b/cc/config/global.go
@@ -215,10 +215,6 @@
 			"frameworks/native/opengl/include",
 			"frameworks/av/include",
 		})
-	// This is used by non-NDK modules to get jni.h. export_include_dirs doesn't help
-	// with this, since there is no associated library.
-	pctx.PrefixedExistentPathsForSourcesVariable("CommonNativehelperInclude", "-I",
-		[]string{"libnativehelper/include_jni"})
 
 	pctx.SourcePathVariable("ClangDefaultBase", ClangDefaultBase)
 	pctx.VariableFunc("ClangBase", func(ctx android.PackageVarContext) string {
diff --git a/cc/config/vndk.go b/cc/config/vndk.go
index cf5674b..0aa6866 100644
--- a/cc/config/vndk.go
+++ b/cc/config/vndk.go
@@ -18,6 +18,7 @@
 // For these libraries, the vendor variants must be installed even if the device
 // has VndkUseCoreVariant set.
 var VndkMustUseVendorVariantList = []string{
+	"android.hardware.authsecret-unstable-ndk_platform",
 	"android.hardware.automotive.occupant_awareness-ndk_platform",
 	"android.hardware.light-ndk_platform",
 	"android.hardware.identity-ndk_platform",
diff --git a/cc/image.go b/cc/image.go
index 13095fc..f89194f 100644
--- a/cc/image.go
+++ b/cc/image.go
@@ -264,31 +264,34 @@
 		productVndkVersion = platformVndkVersion
 	}
 
-	if boardVndkVersion == "" {
+	_, isLLNDKLibrary := m.linker.(*llndkStubDecorator)
+	_, isLLNDKHeaders := m.linker.(*llndkHeadersDecorator)
+	lib := moduleLibraryInterface(m)
+	hasLLNDKStubs := lib != nil && lib.hasLLNDKStubs()
+
+	if isLLNDKLibrary || isLLNDKHeaders || hasLLNDKStubs {
+		// This is an LLNDK library.  The implementation of the library will be on /system,
+		// and vendor and product variants will be created with LLNDK stubs.
+		// The LLNDK libraries need vendor variants even if there is no VNDK.
+		// The obsolete llndk_library and llndk_headers modules also need the vendor variants
+		// so the cc_library LLNDK stubs can depend on them.
+		if hasLLNDKStubs {
+			coreVariantNeeded = true
+		}
+		if platformVndkVersion != "" {
+			vendorVariants = append(vendorVariants, platformVndkVersion)
+			productVariants = append(productVariants, platformVndkVersion)
+		}
+		if boardVndkVersion != "" {
+			vendorVariants = append(vendorVariants, boardVndkVersion)
+		}
+		if productVndkVersion != "" {
+			productVariants = append(productVariants, productVndkVersion)
+		}
+	} else if boardVndkVersion == "" {
 		// If the device isn't compiling against the VNDK, we always
 		// use the core mode.
 		coreVariantNeeded = true
-	} else if _, ok := m.linker.(*llndkStubDecorator); ok {
-		// LL-NDK stubs only exist in the vendor and product variants,
-		// since the real libraries will be used in the core variant.
-		vendorVariants = append(vendorVariants,
-			platformVndkVersion,
-			boardVndkVersion,
-		)
-		productVariants = append(productVariants,
-			platformVndkVersion,
-			productVndkVersion,
-		)
-	} else if _, ok := m.linker.(*llndkHeadersDecorator); ok {
-		// ... and LL-NDK headers as well
-		vendorVariants = append(vendorVariants,
-			platformVndkVersion,
-			boardVndkVersion,
-		)
-		productVariants = append(productVariants,
-			platformVndkVersion,
-			productVndkVersion,
-		)
 	} else if m.isSnapshotPrebuilt() {
 		// Make vendor variants only for the versions in BOARD_VNDK_VERSION and
 		// PRODUCT_EXTRA_VNDK_VERSIONS.
@@ -346,18 +349,6 @@
 		} else {
 			vendorVariants = append(vendorVariants, platformVndkVersion)
 		}
-	} else if lib := moduleLibraryInterface(m); lib != nil && lib.hasLLNDKStubs() {
-		// This is an LLNDK library.  The implementation of the library will be on /system,
-		// and vendor and product variants will be created with LLNDK stubs.
-		coreVariantNeeded = true
-		vendorVariants = append(vendorVariants,
-			platformVndkVersion,
-			boardVndkVersion,
-		)
-		productVariants = append(productVariants,
-			platformVndkVersion,
-			productVndkVersion,
-		)
 	} else {
 		// This is either in /system (or similar: /data), or is a
 		// modules built with the NDK. Modules built with the NDK
diff --git a/cc/llndk_library.go b/cc/llndk_library.go
index bd48501..a46b31c 100644
--- a/cc/llndk_library.go
+++ b/cc/llndk_library.go
@@ -161,6 +161,13 @@
 	*libraryDecorator
 }
 
+func (llndk *llndkHeadersDecorator) linkerDeps(ctx DepsContext, deps Deps) Deps {
+	deps.HeaderLibs = append(deps.HeaderLibs, llndk.Properties.Llndk.Export_llndk_headers...)
+	deps.ReexportHeaderLibHeaders = append(deps.ReexportHeaderLibHeaders,
+		llndk.Properties.Llndk.Export_llndk_headers...)
+	return deps
+}
+
 // llndk_headers contains a set of c/c++ llndk headers files which are imported
 // by other soongs cc modules.
 func llndkHeadersFactory() android.Module {
@@ -178,11 +185,6 @@
 	module.installer = nil
 	module.library = decorator
 
-	module.AddProperties(
-		&module.Properties,
-		&library.MutatedProperties,
-		&library.flagExporter.Properties)
-
 	module.Init()
 
 	return module
diff --git a/cc/makevars.go b/cc/makevars.go
index 8301c6b..48d5636 100644
--- a/cc/makevars.go
+++ b/cc/makevars.go
@@ -154,16 +154,6 @@
 	ctx.Strict("SOONG_STRIP_PATH", "${stripPath}")
 	ctx.Strict("XZ", "${xzCmd}")
 
-	nativeHelperIncludeFlags, err := ctx.Eval("${config.CommonNativehelperInclude}")
-	if err != nil {
-		panic(err)
-	}
-	nativeHelperIncludes, nativeHelperSystemIncludes := splitSystemIncludes(ctx, nativeHelperIncludeFlags)
-	if len(nativeHelperSystemIncludes) > 0 {
-		panic("native helper may not have any system includes")
-	}
-	ctx.Strict("JNI_H_INCLUDE", strings.Join(nativeHelperIncludes, " "))
-
 	includeFlags, err := ctx.Eval("${config.CommonGlobalIncludes}")
 	if err != nil {
 		panic(err)
diff --git a/cc/sanitize.go b/cc/sanitize.go
index 5992611..af17490 100644
--- a/cc/sanitize.go
+++ b/cc/sanitize.go
@@ -89,6 +89,7 @@
 	cfi
 	scs
 	Fuzzer
+	memtag_heap
 )
 
 // Name of the sanitizer variation for this sanitizer type
@@ -106,6 +107,8 @@
 		return "cfi"
 	case scs:
 		return "scs"
+	case memtag_heap:
+		return "memtag_heap"
 	case Fuzzer:
 		return "fuzzer"
 	default:
@@ -120,6 +123,8 @@
 		return "address"
 	case hwasan:
 		return "hwaddress"
+	case memtag_heap:
+		return "memtag_heap"
 	case tsan:
 		return "thread"
 	case intOverflow:
@@ -179,6 +184,7 @@
 	Integer_overflow *bool    `android:"arch_variant"`
 	Scudo            *bool    `android:"arch_variant"`
 	Scs              *bool    `android:"arch_variant"`
+	Memtag_heap      *bool    `android:"arch_variant"`
 
 	// A modifier for ASAN and HWASAN for write only instrumentation
 	Writeonly *bool `android:"arch_variant"`
@@ -190,6 +196,7 @@
 		Undefined        *bool    `android:"arch_variant"`
 		Cfi              *bool    `android:"arch_variant"`
 		Integer_overflow *bool    `android:"arch_variant"`
+		Memtag_heap      *bool    `android:"arch_variant"`
 		Misc_undefined   []string `android:"arch_variant"`
 		No_recover       []string `android:"arch_variant"`
 	} `android:"arch_variant"`
@@ -330,6 +337,11 @@
 			}
 			s.Writeonly = boolPtr(true)
 		}
+		if found, globalSanitizers = removeFromList("memtag_heap", globalSanitizers); found && s.Memtag_heap == nil {
+			if !ctx.Config().MemtagHeapDisabledForPath(ctx.ModuleDir()) {
+				s.Memtag_heap = boolPtr(true)
+			}
+		}
 
 		if len(globalSanitizers) > 0 {
 			ctx.ModuleErrorf("unknown global sanitizer option %s", globalSanitizers[0])
@@ -351,6 +363,25 @@
 		}
 	}
 
+	// cc_test targets default to SYNC MemTag.
+	if ctx.testBinary() && s.Memtag_heap == nil {
+		if !ctx.Config().MemtagHeapDisabledForPath(ctx.ModuleDir()) {
+			s.Memtag_heap = boolPtr(true)
+			s.Diag.Memtag_heap = boolPtr(true)
+		}
+	}
+
+	// Enable Memtag for all components in the include paths (for Aarch64 only)
+	if s.Memtag_heap == nil && ctx.Arch().ArchType == android.Arm64 {
+		if ctx.Config().MemtagHeapSyncEnabledForPath(ctx.ModuleDir()) {
+			s.Memtag_heap = boolPtr(true)
+			s.Diag.Memtag_heap = boolPtr(true)
+		} else if ctx.Config().MemtagHeapAsyncEnabledForPath(ctx.ModuleDir()) {
+			s.Memtag_heap = boolPtr(true)
+			s.Diag.Memtag_heap = boolPtr(false)
+		}
+	}
+
 	// Enable CFI for all components in the include paths (for Aarch64 only)
 	if s.Cfi == nil && ctx.Config().CFIEnabledForPath(ctx.ModuleDir()) && ctx.Arch().ArchType == android.Arm64 {
 		s.Cfi = boolPtr(true)
@@ -381,6 +412,11 @@
 		s.Scs = nil
 	}
 
+	// memtag_heap is only implemented on AArch64.
+	if ctx.Arch().ArchType != android.Arm64 {
+		s.Memtag_heap = nil
+	}
+
 	// Also disable CFI if ASAN is enabled.
 	if Bool(s.Address) || Bool(s.Hwaddress) {
 		s.Cfi = boolPtr(false)
@@ -435,7 +471,7 @@
 
 	if ctx.Os() != android.Windows && (Bool(s.All_undefined) || Bool(s.Undefined) || Bool(s.Address) || Bool(s.Thread) ||
 		Bool(s.Fuzzer) || Bool(s.Safestack) || Bool(s.Cfi) || Bool(s.Integer_overflow) || len(s.Misc_undefined) > 0 ||
-		Bool(s.Scudo) || Bool(s.Hwaddress) || Bool(s.Scs)) {
+		Bool(s.Scudo) || Bool(s.Hwaddress) || Bool(s.Scs) || Bool(s.Memtag_heap)) {
 		sanitize.Properties.SanitizerEnabled = true
 	}
 
@@ -717,6 +753,8 @@
 		return sanitize.Properties.Sanitize.Cfi
 	case scs:
 		return sanitize.Properties.Sanitize.Scs
+	case memtag_heap:
+		return sanitize.Properties.Sanitize.Memtag_heap
 	case Fuzzer:
 		return sanitize.Properties.Sanitize.Fuzzer
 	default:
@@ -731,6 +769,7 @@
 		!sanitize.isSanitizerEnabled(tsan) &&
 		!sanitize.isSanitizerEnabled(cfi) &&
 		!sanitize.isSanitizerEnabled(scs) &&
+		!sanitize.isSanitizerEnabled(memtag_heap) &&
 		!sanitize.isSanitizerEnabled(Fuzzer)
 }
 
@@ -756,6 +795,8 @@
 		sanitize.Properties.Sanitize.Cfi = boolPtr(b)
 	case scs:
 		sanitize.Properties.Sanitize.Scs = boolPtr(b)
+	case memtag_heap:
+		sanitize.Properties.Sanitize.Memtag_heap = boolPtr(b)
 	case Fuzzer:
 		sanitize.Properties.Sanitize.Fuzzer = boolPtr(b)
 	default:
@@ -1032,6 +1073,20 @@
 			sanitizers = append(sanitizers, "shadow-call-stack")
 		}
 
+		if Bool(c.sanitize.Properties.Sanitize.Memtag_heap) && c.binary() {
+			noteDep := "note_memtag_heap_async"
+			if Bool(c.sanitize.Properties.Sanitize.Diag.Memtag_heap) {
+				noteDep = "note_memtag_heap_sync"
+			}
+			depTag := libraryDependencyTag{Kind: staticLibraryDependency, wholeStatic: true}
+			variations := append(mctx.Target().Variations(),
+				blueprint.Variation{Mutator: "link", Variation: "static"})
+			if c.Device() {
+				variations = append(variations, c.ImageVariation())
+			}
+			mctx.AddFarVariationDependencies(variations, depTag, noteDep)
+		}
+
 		if Bool(c.sanitize.Properties.Sanitize.Fuzzer) {
 			sanitizers = append(sanitizers, "fuzzer-no-link")
 		}
diff --git a/cc/test.go b/cc/test.go
index 4ff5bf6..f715a8d 100644
--- a/cc/test.go
+++ b/cc/test.go
@@ -236,6 +236,10 @@
 	return BoolDefault(test.Properties.Gtest, true)
 }
 
+func (test *testDecorator) testBinary() bool {
+	return true
+}
+
 func (test *testDecorator) linkerFlags(ctx ModuleContext, flags Flags) Flags {
 	if !test.gtest() {
 		return flags
diff --git a/cc/testing.go b/cc/testing.go
index 8d92ea2..903f76c 100644
--- a/cc/testing.go
+++ b/cc/testing.go
@@ -445,6 +445,14 @@
 			stl: "none",
 			system_shared_libs: [],
 		}
+
+		cc_library_static {
+			name: "note_memtag_heap_async",
+		}
+
+		cc_library_static {
+			name: "note_memtag_heap_sync",
+		}
 	`
 
 	supportLinuxBionic := false
diff --git a/cmd/soong_build/writedocs.go b/cmd/soong_build/writedocs.go
index 253979e..f2c2c9b 100644
--- a/cmd/soong_build/writedocs.go
+++ b/cmd/soong_build/writedocs.go
@@ -20,7 +20,6 @@
 	"html/template"
 	"io/ioutil"
 	"path/filepath"
-	"reflect"
 	"sort"
 
 	"github.com/google/blueprint/bootstrap"
@@ -97,12 +96,8 @@
 }
 
 func getPackages(ctx *android.Context) ([]*bpdoc.Package, error) {
-	moduleTypeFactories := android.ModuleTypeFactories()
-	bpModuleTypeFactories := make(map[string]reflect.Value)
-	for moduleType, factory := range moduleTypeFactories {
-		bpModuleTypeFactories[moduleType] = reflect.ValueOf(factory)
-	}
-	return bootstrap.ModuleTypeDocs(ctx.Context, bpModuleTypeFactories)
+	moduleTypeFactories := android.ModuleTypeFactoriesForDocs()
+	return bootstrap.ModuleTypeDocs(ctx.Context, moduleTypeFactories)
 }
 
 func writeDocs(ctx *android.Context, filename string) error {
diff --git a/scripts/build-mainline-modules.sh b/scripts/build-mainline-modules.sh
index 6db870f..ea62af4 100755
--- a/scripts/build-mainline-modules.sh
+++ b/scripts/build-mainline-modules.sh
@@ -26,6 +26,7 @@
   platform-mainline-test-exports
   runtime-module-host-exports
   runtime-module-sdk
+  tzdata-module-test-exports
 )
 
 # List of libraries installed on the platform that are needed for ART chroot