Include libprofile-extras to all coverage variants

Bug: http://b/128524141

Include libprofile-extras (defined in system/extras/toolchain-extras) to
all modules that need a coverage variant.  Also add
'-uinit_profile_extras' when linking with coverage.  This causes the
setup code in libprofile-extras to be linked into binaries/libraries
with coverage enabled.

We add the static library to the non-coverage variants as well but is a
no-op for them (since the '-u...' flag is not added for them).

Adding this dependency creates several circular dependencies since
coverage variants were being created for other module types that never
had any compilation or linking done during the build.  This change stops
creating coverage variants for toolchain_library, cc_prebuilt_library_*,
cc_library_headers module types (by adding a function to the linker
interface to specify whether native coverage is enabled).

Test: m NATIVE_COVERAGE=true COVERAGE_PATHS=*
Test: blueline_coverage target in internal branch (using forrest)
Change-Id: I5db876eb953639a55ba007248dd24e497f987730

cc/binary.go

@@ -417,6 +417,10 @@ func (binary *binaryDecorator) symlinkList() []string {
 	return binary.symlinks
 }
 
+func (binary *binaryDecorator) nativeCoverage() bool {
+	return true
+}
+
 // /system/bin/linker -> /apex/com.android.runtime/bin/linker
 func (binary *binaryDecorator) installSymlinkToRuntimeApex(ctx ModuleContext, file android.Path) {
 	dir := binary.baseInstaller.installDir(ctx)

cc/cc.go

@@ -267,6 +267,7 @@ type ModuleContextIntf interface {
 	isStubs() bool
 	bootstrap() bool
 	mustUseVendorVariant() bool
+	nativeCoverage() bool
 }
 
 type ModuleContext interface {
@@ -312,6 +313,8 @@ type linker interface {
 	link(ctx ModuleContext, flags Flags, deps PathDeps, objs Objects) android.Path
 	appendLdflags([]string)
 	unstrippedOutputFilePath() android.Path
+
+	nativeCoverage() bool
 }
 
 type installer interface {
@@ -604,6 +607,10 @@ func (c *Module) bootstrap() bool {
 	return Bool(c.Properties.Bootstrap)
 }
 
+func (c *Module) nativeCoverage() bool {
+	return c.linker != nil && c.linker.nativeCoverage()
+}
+
 func isBionic(name string) bool {
 	switch name {
 	case "libc", "libm", "libdl", "linker":
@@ -794,6 +801,10 @@ func (ctx *moduleContextImpl) bootstrap() bool {
 	return ctx.mod.bootstrap()
 }
 
+func (ctx *moduleContextImpl) nativeCoverage() bool {
+	return ctx.mod.nativeCoverage()
+}
+
 func newBaseModule(hod android.HostOrDeviceSupported, multilib android.Multilib) *Module {
 	return &Module{
 		hod:      hod,

cc/coverage.go

@@ -42,6 +42,23 @@ func (cov *coverage) props() []interface{} {
 }
 
 func (cov *coverage) deps(ctx BaseModuleContext, deps Deps) Deps {
+	if cov.Properties.NeedCoverageBuild {
+		// Link libprofile-extras/libprofile-extras_ndk when coverage
+		// variant is required.  This is a no-op unless coverage is
+		// actually enabled during linking, when
+		// '-uinit_profile_extras' is added (in flags()) to force the
+		// setup code in libprofile-extras be linked into the
+		// binary/library.
+		//
+		// We cannot narrow it further to only the 'cov' variant since
+		// the mutator hasn't run (and we don't have the 'cov' variant
+		// yet).
+		if !ctx.useSdk() {
+			deps.LateStaticLibs = append(deps.LateStaticLibs, "libprofile-extras")
+		} else {
+			deps.LateStaticLibs = append(deps.LateStaticLibs, "libprofile-extras_ndk")
+		}
+	}
 	return deps
 }
 
@@ -96,6 +113,9 @@ func (cov *coverage) flags(ctx ModuleContext, flags Flags) Flags {
 
 	if cov.linkCoverage {
 		flags.LdFlags = append(flags.LdFlags, "--coverage")
+
+		// Force linking of constructor/setup code in libprofile-extras
+		flags.LdFlags = append(flags.LdFlags, "-uinit_profile_extras")
 	}
 
 	return flags
@@ -113,10 +133,8 @@ func (cov *coverage) begin(ctx BaseModuleContext) {
 	if ctx.Host() {
 		// TODO(dwillemsen): because of -nodefaultlibs, we must depend on libclang_rt.profile-*.a
 		// Just turn off for now.
-	} else if ctx.isStubs() {
-		// Do not enable coverage for platform stub libraries
-	} else if ctx.isNDKStubLibrary() {
-		// Do not enable coverage for NDK stub libraries
+	} else if !ctx.nativeCoverage() {
+		// Native coverage is not supported for this module type.
 	} else {
 		// Check if Native_coverage is set to false.  This property defaults to true.
 		needCoverageVariant = BoolDefault(cov.Properties.Native_coverage, true)

cc/library.go

@@ -761,6 +761,13 @@ func (library *libraryDecorator) unstrippedOutputFilePath() android.Path {
 	return library.unstrippedOutputFile
 }
 
+func (library *libraryDecorator) nativeCoverage() bool {
+	if library.header() || library.buildStubs() {
+		return false
+	}
+	return true
+}
+
 func getRefAbiDumpFile(ctx ModuleContext, vndkVersion, fileName string) android.Path {
 	isLlndk := inList(ctx.baseModuleName(), llndkLibraries) || inList(ctx.baseModuleName(), ndkMigratedLibs)
 

cc/llndk_library.go

@@ -161,6 +161,10 @@ func (stub *llndkStubDecorator) link(ctx ModuleContext, flags Flags, deps PathDe
 	return stub.libraryDecorator.link(ctx, flags, deps, objs)
 }
 
+func (stub *llndkStubDecorator) nativeCoverage() bool {
+	return false
+}
+
 func NewLLndkStubLibrary() *Module {
 	module, library := NewLibrary(android.DeviceSupported)
 	library.BuildOnlyShared()

cc/ndk_library.go

@@ -338,6 +338,10 @@ func (stub *stubDecorator) link(ctx ModuleContext, flags Flags, deps PathDeps,
 	return stub.libraryDecorator.link(ctx, flags, deps, objs)
 }
 
+func (stub *stubDecorator) nativeCoverage() bool {
+	return false
+}
+
 func (stub *stubDecorator) install(ctx ModuleContext, path android.Path) {
 	arch := ctx.Target().Arch.ArchType.Name
 	apiLevel := stub.properties.ApiLevel

cc/object.go

@@ -114,3 +114,7 @@ func (object *objectLinker) link(ctx ModuleContext,
 func (object *objectLinker) unstrippedOutputFilePath() android.Path {
 	return nil
 }
+
+func (object *objectLinker) nativeCoverage() bool {
+	return true
+}

cc/prebuilt.go

@@ -108,6 +108,10 @@ func (p *prebuiltLibraryLinker) shared() bool {
 	return p.libraryDecorator.shared()
 }
 
+func (p *prebuiltLibraryLinker) nativeCoverage() bool {
+	return false
+}
+
 func prebuiltSharedLibraryFactory() android.Module {
 	module, _ := NewPrebuiltSharedLibrary(android.HostAndDeviceSupported)
 	return module.Init()

cc/toolchain_library.go

@@ -77,3 +77,7 @@ func (library *toolchainLibraryDecorator) link(ctx ModuleContext,
 
 	return android.PathForSource(ctx, *library.Properties.Src)
 }
+
+func (library *toolchainLibraryDecorator) nativeCoverage() bool {
+	return false
+}