Merge changes I64a5f3c9,I1ed0a380 into main

* changes:
  Optimize mutator contexts
  Optimize InstallPath.String()

android/arch.go

@@ -426,6 +426,7 @@ func osMutator(bpctx blueprint.BottomUpMutatorContext) {
 	// filters out non-Soong modules.  Now that we've handled them, create a
 	// normal android.BottomUpMutatorContext.
 	mctx := bottomUpMutatorContextFactory(bpctx, module, false)
+	defer bottomUpMutatorContextPool.Put(mctx)
 
 	base := module.base()
 
@@ -572,6 +573,7 @@ func archMutator(bpctx blueprint.BottomUpMutatorContext) {
 	// filters out non-Soong modules.  Now that we've handled them, create a
 	// normal android.BottomUpMutatorContext.
 	mctx := bottomUpMutatorContextFactory(bpctx, module, false)
+	defer bottomUpMutatorContextPool.Put(mctx)
 
 	base := module.base()
 

android/mutator.go

@@ -15,6 +15,8 @@
 package android
 
 import (
+	"sync"
+
 	"github.com/google/blueprint"
 )
 
@@ -328,29 +330,52 @@ type BottomUpMutatorContext interface {
 	SetVariationProvider(module blueprint.Module, provider blueprint.AnyProviderKey, value interface{})
 }
 
+// An outgoingTransitionContextImpl and incomingTransitionContextImpl is created for every dependency of every module
+// for each transition mutator.  bottomUpMutatorContext and topDownMutatorContext are created once for every module
+// for every BottomUp or TopDown mutator.  Use a global pool for each to avoid reallocating every time.
+var (
+	outgoingTransitionContextPool = sync.Pool{
+		New: func() any { return &outgoingTransitionContextImpl{} },
+	}
+	incomingTransitionContextPool = sync.Pool{
+		New: func() any { return &incomingTransitionContextImpl{} },
+	}
+	bottomUpMutatorContextPool = sync.Pool{
+		New: func() any { return &bottomUpMutatorContext{} },
+	}
+
+	topDownMutatorContextPool = sync.Pool{
+		New: func() any { return &topDownMutatorContext{} },
+	}
+)
+
 type bottomUpMutatorContext struct {
 	bp blueprint.BottomUpMutatorContext
 	baseModuleContext
 	finalPhase bool
 }
 
+// callers must immediately follow the call to this function with defer bottomUpMutatorContextPool.Put(mctx).
 func bottomUpMutatorContextFactory(ctx blueprint.BottomUpMutatorContext, a Module,
 	finalPhase bool) BottomUpMutatorContext {
 
 	moduleContext := a.base().baseModuleContextFactory(ctx)
-
-	return &bottomUpMutatorContext{
+	mctx := bottomUpMutatorContextPool.Get().(*bottomUpMutatorContext)
+	*mctx = bottomUpMutatorContext{
 		bp:                ctx,
 		baseModuleContext: moduleContext,
 		finalPhase:        finalPhase,
 	}
+	return mctx
 }
 
 func (x *registerMutatorsContext) BottomUp(name string, m BottomUpMutator) MutatorHandle {
 	finalPhase := x.finalPhase
 	f := func(ctx blueprint.BottomUpMutatorContext) {
 		if a, ok := ctx.Module().(Module); ok {
-			m(bottomUpMutatorContextFactory(ctx, a, finalPhase))
+			mctx := bottomUpMutatorContextFactory(ctx, a, finalPhase)
+			defer bottomUpMutatorContextPool.Put(mctx)
+			m(mctx)
 		}
 	}
 	mutator := &mutator{name: x.mutatorName(name), bottomUpMutator: f}
@@ -514,7 +539,9 @@ func (c *outgoingTransitionContextImpl) DeviceConfig() DeviceConfig {
 
 func (a *androidTransitionMutator) OutgoingTransition(bpctx blueprint.OutgoingTransitionContext, sourceVariation string) string {
 	if m, ok := bpctx.Module().(Module); ok {
-		ctx := &outgoingTransitionContextImpl{
+		ctx := outgoingTransitionContextPool.Get().(*outgoingTransitionContextImpl)
+		defer outgoingTransitionContextPool.Put(ctx)
+		*ctx = outgoingTransitionContextImpl{
 			archModuleContext: m.base().archModuleContextFactory(bpctx),
 			bp:                bpctx,
 		}
@@ -543,7 +570,9 @@ func (c *incomingTransitionContextImpl) DeviceConfig() DeviceConfig {
 
 func (a *androidTransitionMutator) IncomingTransition(bpctx blueprint.IncomingTransitionContext, incomingVariation string) string {
 	if m, ok := bpctx.Module().(Module); ok {
-		ctx := &incomingTransitionContextImpl{
+		ctx := incomingTransitionContextPool.Get().(*incomingTransitionContextImpl)
+		defer incomingTransitionContextPool.Put(ctx)
+		*ctx = incomingTransitionContextImpl{
 			archModuleContext: m.base().archModuleContextFactory(bpctx),
 			bp:                bpctx,
 		}
@@ -555,7 +584,9 @@ func (a *androidTransitionMutator) IncomingTransition(bpctx blueprint.IncomingTr
 
 func (a *androidTransitionMutator) Mutate(ctx blueprint.BottomUpMutatorContext, variation string) {
 	if am, ok := ctx.Module().(Module); ok {
-		a.mutator.Mutate(bottomUpMutatorContextFactory(ctx, am, a.finalPhase), variation)
+		mctx := bottomUpMutatorContextFactory(ctx, am, a.finalPhase)
+		defer bottomUpMutatorContextPool.Put(mctx)
+		a.mutator.Mutate(mctx, variation)
 	}
 }
 
@@ -578,7 +609,9 @@ func (x *registerMutatorsContext) TopDown(name string, m TopDownMutator) Mutator
 	f := func(ctx blueprint.TopDownMutatorContext) {
 		if a, ok := ctx.Module().(Module); ok {
 			moduleContext := a.base().baseModuleContextFactory(ctx)
-			actx := &topDownMutatorContext{
+			actx := topDownMutatorContextPool.Get().(*topDownMutatorContext)
+			defer topDownMutatorContextPool.Put(actx)
+			*actx = topDownMutatorContext{
 				bp:                ctx,
 				baseModuleContext: moduleContext,
 			}

android/paths.go

@@ -1661,6 +1661,8 @@ type InstallPath struct {
 
 	// makePath indicates whether this path is for Soong (false) or Make (true).
 	makePath bool
+
+	fullPath string
 }
 
 // Will panic if called from outside a test environment.
@@ -1673,7 +1675,12 @@ func ensureTestOnly() {
 
 func (p InstallPath) RelativeToTop() Path {
 	ensureTestOnly()
-	p.soongOutDir = OutSoongDir
+	if p.makePath {
+		p.soongOutDir = OutDir
+	} else {
+		p.soongOutDir = OutSoongDir
+	}
+	p.fullPath = filepath.Join(p.soongOutDir, p.path)
 	return p
 }
 
@@ -1691,12 +1698,7 @@ var _ WritablePath = InstallPath{}
 func (p InstallPath) writablePath() {}
 
 func (p InstallPath) String() string {
-	if p.makePath {
-		// Make path starts with out/ instead of out/soong.
-		return filepath.Join(p.soongOutDir, "../", p.path)
-	} else {
-		return filepath.Join(p.soongOutDir, p.path)
-	}
+	return p.fullPath
 }
 
 // PartitionDir returns the path to the partition where the install path is rooted at. It is
@@ -1726,6 +1728,7 @@ func (p InstallPath) Join(ctx PathContext, paths ...string) InstallPath {
 
 func (p InstallPath) withRel(rel string) InstallPath {
 	p.basePath = p.basePath.withRel(rel)
+	p.fullPath = filepath.Join(p.fullPath, rel)
 	return p
 }
 
@@ -1769,6 +1772,25 @@ func osAndArch(ctx ModuleInstallPathContext) (OsType, ArchType) {
 	return os, arch
 }
 
+func pathForPartitionInstallDir(ctx PathContext, partition, partitionPath string, makePath bool) InstallPath {
+	fullPath := ctx.Config().SoongOutDir()
+	if makePath {
+		// Make path starts with out/ instead of out/soong.
+		fullPath = filepath.Join(fullPath, "../", partitionPath)
+	} else {
+		fullPath = filepath.Join(fullPath, partitionPath)
+	}
+
+	return InstallPath{
+		basePath:     basePath{partitionPath, ""},
+		soongOutDir:  ctx.Config().soongOutDir,
+		partitionDir: partitionPath,
+		partition:    partition,
+		makePath:     makePath,
+		fullPath:     fullPath,
+	}
+}
+
 func pathForInstall(ctx PathContext, os OsType, arch ArchType, partition string,
 	pathComponents ...string) InstallPath {
 
@@ -1805,27 +1827,12 @@ func pathForInstall(ctx PathContext, os OsType, arch ArchType, partition string,
 		reportPathError(ctx, err)
 	}
 
-	base := InstallPath{
-		basePath:     basePath{partitionPath, ""},
-		soongOutDir:  ctx.Config().soongOutDir,
-		partitionDir: partitionPath,
-		partition:    partition,
-	}
-
-	if ctx.Config().KatiEnabled() {
-		base.makePath = true
-	}
-
+	base := pathForPartitionInstallDir(ctx, partition, partitionPath, ctx.Config().KatiEnabled())
 	return base.Join(ctx, pathComponents...)
 }
 
 func pathForNdkOrSdkInstall(ctx PathContext, prefix string, paths []string) InstallPath {
-	base := InstallPath{
-		basePath:     basePath{prefix, ""},
-		soongOutDir:  ctx.Config().soongOutDir,
-		partitionDir: prefix,
-		makePath:     false,
-	}
+	base := pathForPartitionInstallDir(ctx, "", prefix, false)
 	return base.Join(ctx, paths...)
 }