bloaty: measure stripped Rust binaries

Modify bloaty's MeasureSizeForPath to allow a module to provide multiple
paths. This is used to measure both unstripped and stripped
libraries/binaries. Add unit test to ensure correct measurements are
generated for Rust.

Test: m out/soong/binary_sizes.pb.gz
Change-Id: I59439b77dbf1cf5ad71e1c02996a6a90938536b4

bloaty/Android.bp

@@ -11,6 +11,7 @@ bootstrap_go_package {
     ],
     srcs: [
         "bloaty.go",
+        "testing.go",
     ],
     pluginFor: ["soong_build"],
 }

bloaty/bloaty.go

@@ -52,12 +52,28 @@ func init() {
 	pctx.SourcePathVariable("bloaty", "prebuilts/build-tools/${hostPrebuiltTag}/bin/bloaty")
 	pctx.HostBinToolVariable("bloatyMerger", "bloaty_merger")
 	android.RegisterSingletonType("file_metrics", fileSizesSingleton)
-	fileSizeMeasurerKey = blueprint.NewProvider(android.ModuleOutPath{})
+	fileSizeMeasurerKey = blueprint.NewProvider(measuredFiles{})
 }
 
-// MeasureSizeForPath should be called by binary producers (e.g. in builder.go).
-func MeasureSizeForPath(ctx android.ModuleContext, filePath android.WritablePath) {
-	ctx.SetProvider(fileSizeMeasurerKey, filePath)
+// measuredFiles contains the paths of the files measured by a module.
+type measuredFiles struct {
+	paths []android.WritablePath
+}
+
+// MeasureSizeForPaths should be called by binary producers to measure the
+// sizes of artifacts. It must only be called once per module; it will panic
+// otherwise.
+func MeasureSizeForPaths(ctx android.ModuleContext, paths ...android.OptionalPath) {
+	mf := measuredFiles{}
+	for _, p := range paths {
+		if !p.Valid() {
+			continue
+		}
+		if p, ok := p.Path().(android.WritablePath); ok {
+			mf.paths = append(mf.paths, p)
+		}
+	}
+	ctx.SetProvider(fileSizeMeasurerKey, mf)
 }
 
 type sizesSingleton struct{}
@@ -68,21 +84,22 @@ func fileSizesSingleton() android.Singleton {
 
 func (singleton *sizesSingleton) GenerateBuildActions(ctx android.SingletonContext) {
 	var deps android.Paths
-	// Visit all modules. If the size provider give us a binary path to measure,
-	// create the rule to measure it.
 	ctx.VisitAllModules(func(m android.Module) {
 		if !ctx.ModuleHasProvider(m, fileSizeMeasurerKey) {
 			return
 		}
-		filePath := ctx.ModuleProvider(m, fileSizeMeasurerKey).(android.ModuleOutPath)
-		sizeFile := filePath.InSameDir(ctx, filePath.Base()+bloatyDescriptorExt)
-		ctx.Build(pctx, android.BuildParams{
-			Rule:        bloaty,
-			Description: "bloaty " + filePath.Rel(),
-			Input:       filePath,
-			Output:      sizeFile,
-		})
-		deps = append(deps, sizeFile)
+		filePaths := ctx.ModuleProvider(m, fileSizeMeasurerKey).(measuredFiles)
+		for _, path := range filePaths.paths {
+			filePath := path.(android.ModuleOutPath)
+			sizeFile := filePath.InSameDir(ctx, filePath.Base()+bloatyDescriptorExt)
+			ctx.Build(pctx, android.BuildParams{
+				Rule:        bloaty,
+				Description: "bloaty " + filePath.Rel(),
+				Input:       filePath,
+				Output:      sizeFile,
+			})
+			deps = append(deps, sizeFile)
+		}
 	})
 
 	ctx.Build(pctx, android.BuildParams{

bloaty/testing.go

@@ -0,0 +1,25 @@
+// 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 bloaty
+
+import (
+	"android/soong/android"
+)
+
+// Preparer that will define the default bloaty singleton.
+var PrepareForTestWithBloatyDefaultModules = android.GroupFixturePreparers(
+	android.FixtureRegisterWithContext(func(ctx android.RegistrationContext) {
+		ctx.RegisterSingletonType("file_metrics", fileSizesSingleton)
+	}))

rust/builder.go

@@ -21,7 +21,6 @@ import (
 	"github.com/google/blueprint"
 
 	"android/soong/android"
-	"android/soong/bloaty"
 	"android/soong/rust/config"
 )
 
@@ -254,8 +253,6 @@ func transformSrctoCrate(ctx ModuleContext, main android.Path, deps PathDeps, fl
 		implicits = append(implicits, clippyFile)
 	}
 
-	bloaty.MeasureSizeForPath(ctx, outputFile)
-
 	ctx.Build(pctx, android.BuildParams{
 		Rule:            rustc,
 		Description:     "rustc " + main.Rel(),

rust/rust.go

@@ -22,6 +22,7 @@ import (
 	"github.com/google/blueprint/proptools"
 
 	"android/soong/android"
+	"android/soong/bloaty"
 	"android/soong/cc"
 	cc_config "android/soong/cc/config"
 	"android/soong/rust/config"
@@ -731,8 +732,8 @@ func (mod *Module) GenerateAndroidBuildActions(actx android.ModuleContext) {
 	if mod.compiler != nil && !mod.compiler.Disabled() {
 		mod.compiler.initialize(ctx)
 		unstrippedOutputFile := mod.compiler.compile(ctx, flags, deps)
-
 		mod.unstrippedOutputFile = android.OptionalPathForPath(unstrippedOutputFile)
+		bloaty.MeasureSizeForPaths(ctx, mod.compiler.strippedOutputFilePath(), mod.unstrippedOutputFile)
 
 		apexInfo := actx.Provider(android.ApexInfoProvider).(android.ApexInfo)
 		if mod.installable(apexInfo) {

rust/rust_test.go

@@ -384,3 +384,17 @@ func TestMultilib(t *testing.T) {
 	_ = ctx.ModuleForTests("libfoo", "android_arm64_armv8-a_rlib_dylib-std")
 	_ = ctx.ModuleForTests("libfoo", "android_arm_armv7-a-neon_rlib_dylib-std")
 }
+
+// Test that library size measurements are generated.
+func TestLibrarySizes(t *testing.T) {
+	ctx := testRust(t, `
+		rust_library_dylib {
+			name: "libwaldo",
+			srcs: ["foo.rs"],
+			crate_name: "waldo",
+		}`)
+
+	m := ctx.SingletonForTests("file_metrics")
+	m.Output("libwaldo.dylib.so.bloaty.csv")
+	m.Output("stripped/libwaldo.dylib.so.bloaty.csv")
+}

rust/testing.go

@@ -16,6 +16,7 @@ package rust
 
 import (
 	"android/soong/android"
+	"android/soong/bloaty"
 	"android/soong/cc"
 )
 
@@ -34,6 +35,7 @@ const rustDefaultsDir = "defaults/rust/"
 // Preparer that will define default rust modules, e.g. standard prebuilt modules.
 var PrepareForTestWithRustDefaultModules = android.GroupFixturePreparers(
 	cc.PrepareForTestWithCcDefaultModules,
+	bloaty.PrepareForTestWithBloatyDefaultModules,
 	PrepareForTestWithRustBuildComponents,
 	android.FixtureAddTextFile(rustDefaultsDir+"Android.bp", GatherRequiredDepsForTest()),
 )