Experimental code to support build action caching.
Bug: 335718784
Test: build locally
Change-Id: Icc1f1fb15f9fe305e95dd51e2e7aff1e9cbf340c
diff --git a/cmd/soong_build/main.go b/cmd/soong_build/main.go
index 3dac8bd..a8be7ec 100644
--- a/cmd/soong_build/main.go
+++ b/cmd/soong_build/main.go
@@ -16,6 +16,7 @@
import (
"bytes"
+ "encoding/json"
"errors"
"flag"
"fmt"
@@ -28,11 +29,11 @@
"android/soong/android/allowlists"
"android/soong/bp2build"
"android/soong/shared"
-
"github.com/google/blueprint"
"github.com/google/blueprint/bootstrap"
"github.com/google/blueprint/deptools"
"github.com/google/blueprint/metrics"
+ "github.com/google/blueprint/proptools"
androidProtobuf "google.golang.org/protobuf/android"
)
@@ -49,6 +50,14 @@
cmdlineArgs android.CmdArgs
)
+const configCacheFile = "config.cache"
+
+type ConfigCache struct {
+ EnvDepsHash uint64
+ ProductVariableFileTimestamp int64
+ SoongBuildFileTimestamp int64
+}
+
func init() {
// Flags that make sense in every mode
flag.StringVar(&topDir, "top", "", "Top directory of the Android source tree")
@@ -82,6 +91,7 @@
// Flags that probably shouldn't be flags of soong_build, but we haven't found
// the time to remove them yet
flag.BoolVar(&cmdlineArgs.RunGoTests, "t", false, "build and run go tests during bootstrap")
+ flag.BoolVar(&cmdlineArgs.IncrementalBuildActions, "incremental-build-actions", false, "generate build actions incrementally")
// Disable deterministic randomization in the protobuf package, so incremental
// builds with unrelated Soong changes don't trigger large rebuilds (since we
@@ -218,6 +228,60 @@
maybeQuit(err, "error writing depfile '%s'", depFile)
}
+// Check if there are changes to the environment file, product variable file and
+// soong_build binary, in which case no incremental will be performed.
+func incrementalValid(config android.Config, configCacheFile string) (*ConfigCache, bool) {
+ var newConfigCache ConfigCache
+ data, err := os.ReadFile(shared.JoinPath(topDir, usedEnvFile))
+ if err != nil {
+ // Clean build
+ if os.IsNotExist(err) {
+ data = []byte{}
+ } else {
+ maybeQuit(err, "")
+ }
+ }
+
+ newConfigCache.EnvDepsHash, err = proptools.CalculateHash(data)
+ newConfigCache.ProductVariableFileTimestamp = getFileTimestamp(filepath.Join(topDir, cmdlineArgs.SoongVariables))
+ newConfigCache.SoongBuildFileTimestamp = getFileTimestamp(filepath.Join(topDir, config.HostToolDir(), "soong_build"))
+ //TODO(b/344917959): out/soong/dexpreopt.config might need to be checked as well.
+
+ file, err := os.Open(configCacheFile)
+ if err != nil && os.IsNotExist(err) {
+ return &newConfigCache, false
+ }
+ maybeQuit(err, "")
+ defer file.Close()
+
+ var configCache ConfigCache
+ decoder := json.NewDecoder(file)
+ err = decoder.Decode(&configCache)
+ maybeQuit(err, "")
+
+ return &newConfigCache, newConfigCache == configCache
+}
+
+func getFileTimestamp(file string) int64 {
+ stat, err := os.Stat(file)
+ if err == nil {
+ return stat.ModTime().UnixMilli()
+ } else if !os.IsNotExist(err) {
+ maybeQuit(err, "")
+ }
+ return 0
+}
+
+func writeConfigCache(configCache *ConfigCache, configCacheFile string) {
+ file, err := os.Create(configCacheFile)
+ maybeQuit(err, "")
+ defer file.Close()
+
+ encoder := json.NewEncoder(file)
+ err = encoder.Encode(*configCache)
+ maybeQuit(err, "")
+}
+
// runSoongOnlyBuild runs the standard Soong build in a number of different modes.
func runSoongOnlyBuild(ctx *android.Context, extraNinjaDeps []string) string {
ctx.EventHandler.Begin("soong_build")
@@ -319,8 +383,26 @@
ctx := newContext(configuration)
android.StartBackgroundMetrics(configuration)
+ var configCache *ConfigCache
+ configFile := filepath.Join(topDir, ctx.Config().OutDir(), configCacheFile)
+ incremental := false
+ ctx.SetIncrementalEnabled(cmdlineArgs.IncrementalBuildActions)
+ if cmdlineArgs.IncrementalBuildActions {
+ configCache, incremental = incrementalValid(ctx.Config(), configFile)
+ }
+ ctx.SetIncrementalAnalysis(incremental)
+
ctx.Register()
finalOutputFile := runSoongOnlyBuild(ctx, extraNinjaDeps)
+
+ if ctx.GetIncrementalEnabled() {
+ data, err := shared.EnvFileContents(configuration.EnvDeps())
+ maybeQuit(err, "")
+ configCache.EnvDepsHash, err = proptools.CalculateHash(data)
+ maybeQuit(err, "")
+ writeConfigCache(configCache, configFile)
+ }
+
writeMetrics(configuration, ctx.EventHandler, metricsDir)
writeUsedEnvironmentFile(configuration)