Export files to install as a depset

Export files to install through a depset instead of a list to reduce
the size at each module.

Bug: 124313442
Test: m checkbuild
Change-Id: I6a51c89acc9f0f3a9c3c792d3ef8a7cfd6b8bef2

android/module.go

@@ -1005,6 +1005,7 @@ type ModuleBase struct {
 
 	noAddressSanitizer bool
 	installFiles       InstallPaths
+	installFilesDepSet *installPathsDepSet
 	checkbuildFiles    Paths
 	packagingSpecs     []PackagingSpec
 	noticeFiles        Paths
@@ -1338,19 +1339,15 @@ func (m *ModuleBase) ExportedToMake() bool {
 
 // computeInstallDeps finds the installed paths of all dependencies that have a dependency
 // tag that is annotated as needing installation via the IsInstallDepNeeded method.
-func (m *ModuleBase) computeInstallDeps(ctx blueprint.ModuleContext) InstallPaths {
-	var result InstallPaths
-	ctx.WalkDeps(func(child, parent blueprint.Module) bool {
-		if a, ok := child.(Module); ok {
-			if IsInstallDepNeeded(ctx.OtherModuleDependencyTag(child)) {
-				result = append(result, a.FilesToInstall()...)
-				return true
-			}
+func (m *ModuleBase) computeInstallDeps(ctx ModuleContext) []*installPathsDepSet {
+	var installDeps []*installPathsDepSet
+	ctx.VisitDirectDeps(func(dep Module) {
+		if IsInstallDepNeeded(ctx.OtherModuleDependencyTag(dep)) {
+			installDeps = append(installDeps, dep.base().installFilesDepSet)
 		}
-		return false
 	})
 
-	return result
+	return installDeps
 }
 
 func (m *ModuleBase) FilesToInstall() InstallPaths {
@@ -1587,11 +1584,15 @@ func (m *ModuleBase) GenerateBuildActions(blueprintCtx blueprint.ModuleContext)
 		module:            m.module,
 		bp:                blueprintCtx,
 		baseModuleContext: m.baseModuleContextFactory(blueprintCtx),
-		installDeps:       m.computeInstallDeps(blueprintCtx),
-		installFiles:      m.installFiles,
 		variables:         make(map[string]string),
 	}
 
+	dependencyInstallFiles := m.computeInstallDeps(ctx)
+	// set m.installFilesDepSet to only the transitive dependencies to be used as the dependencies
+	// of installed files of this module.  It will be replaced by a depset including the installed
+	// files of this module at the end for use by modules that depend on this one.
+	m.installFilesDepSet = newInstallPathsDepSet(nil, dependencyInstallFiles)
+
 	// Temporarily continue to call blueprintCtx.GetMissingDependencies() to maintain the previous behavior of never
 	// reporting missing dependency errors in Blueprint when AllowMissingDependencies == true.
 	// TODO: This will be removed once defaults modules handle missing dependency errors
@@ -1700,6 +1701,8 @@ func (m *ModuleBase) GenerateBuildActions(blueprintCtx blueprint.ModuleContext)
 		}
 	}
 
+	m.installFilesDepSet = newInstallPathsDepSet(m.installFiles, dependencyInstallFiles)
+
 	m.buildParams = ctx.buildParams
 	m.ruleParams = ctx.ruleParams
 	m.variables = ctx.variables
@@ -1874,7 +1877,6 @@ type moduleContext struct {
 	bp blueprint.ModuleContext
 	baseModuleContext
 	packagingSpecs  []PackagingSpec
-	installDeps     InstallPaths
 	installFiles    InstallPaths
 	checkbuildFiles Paths
 	module          Module
@@ -2420,8 +2422,7 @@ func (m *moduleContext) installFile(installPath InstallPath, name string, srcPat
 	m.module.base().hooks.runInstallHooks(m, srcPath, fullInstallPath, false)
 
 	if !m.skipInstall(fullInstallPath) {
-
-		deps = append(deps, m.installDeps.Paths()...)
+		deps = append(deps, m.module.base().installFilesDepSet.ToList().Paths()...)
 
 		var implicitDeps, orderOnlyDeps Paths
 
@@ -2858,3 +2859,23 @@ func CheckBlueprintSyntax(ctx BaseModuleContext, filename string, contents strin
 	bpctx := ctx.blueprintBaseModuleContext()
 	return blueprint.CheckBlueprintSyntax(bpctx.ModuleFactories(), filename, contents)
 }
+
+// installPathsDepSet is a thin type-safe wrapper around the generic depSet.  It always uses
+// topological order.
+type installPathsDepSet struct {
+	depSet
+}
+
+// newInstallPathsDepSet returns an immutable packagingSpecsDepSet with the given direct and
+// transitive contents.
+func newInstallPathsDepSet(direct InstallPaths, transitive []*installPathsDepSet) *installPathsDepSet {
+	return &installPathsDepSet{*newDepSet(TOPOLOGICAL, direct, transitive)}
+}
+
+// ToList returns the installPathsDepSet flattened to a list in topological order.
+func (d *installPathsDepSet) ToList() InstallPaths {
+	if d == nil {
+		return nil
+	}
+	return d.depSet.ToList().(InstallPaths)
+}

android/paths.go

@@ -542,6 +542,45 @@ func firstUniquePathsMap(list Paths) Paths {
 	return list[:k]
 }
 
+// FirstUniqueInstallPaths returns all unique elements of an InstallPaths, keeping the first copy of each.  It
+// modifies the InstallPaths slice contents in place, and returns a subslice of the original slice.
+func FirstUniqueInstallPaths(list InstallPaths) InstallPaths {
+	// 128 was chosen based on BenchmarkFirstUniquePaths results.
+	if len(list) > 128 {
+		return firstUniqueInstallPathsMap(list)
+	}
+	return firstUniqueInstallPathsList(list)
+}
+
+func firstUniqueInstallPathsList(list InstallPaths) InstallPaths {
+	k := 0
+outer:
+	for i := 0; i < len(list); i++ {
+		for j := 0; j < k; j++ {
+			if list[i] == list[j] {
+				continue outer
+			}
+		}
+		list[k] = list[i]
+		k++
+	}
+	return list[:k]
+}
+
+func firstUniqueInstallPathsMap(list InstallPaths) InstallPaths {
+	k := 0
+	seen := make(map[InstallPath]bool, len(list))
+	for i := 0; i < len(list); i++ {
+		if seen[list[i]] {
+			continue
+		}
+		seen[list[i]] = true
+		list[k] = list[i]
+		k++
+	}
+	return list[:k]
+}
+
 // LastUniquePaths returns all unique elements of a Paths, keeping the last copy of each.  It
 // modifies the Paths slice contents in place, and returns a subslice of the original slice.
 func LastUniquePaths(list Paths) Paths {