Add support for toc optimization in soong
Skip relinking against shared libraries whose interface hasn't changed.
Test: mmma -j frameworks/native/libs/gui
Test: touch frameworks/native/libs/gui/BufferItem.cpp
Test: mmma -j frameworks/native/libs/gui, see nothing relinks past libgui
Bug: 26014946
Change-Id: I4d4b8da6a35c682341ae51869f5c72b51e192053
diff --git a/cc/library.go b/cc/library.go
index 7cc587f..53c9a58 100644
--- a/cc/library.go
+++ b/cc/library.go
@@ -18,6 +18,7 @@
"strings"
"github.com/google/blueprint"
+ "github.com/google/blueprint/pathtools"
"android/soong"
"android/soong/android"
@@ -158,6 +159,8 @@
// For reusing static library objects for shared library
reuseObjFiles android.Paths
+ // table-of-contents file to optimize out relinking when possible
+ tocFile android.OptionalPath
flagExporter
stripper
@@ -269,6 +272,7 @@
static() bool
objs() android.Paths
reuseObjs() android.Paths
+ toc() android.OptionalPath
// Returns true if the build options for the module have selected a static or shared build
buildStatic() bool
@@ -434,10 +438,28 @@
}
}
+ linkerDeps = append(linkerDeps, deps.SharedLibsDeps...)
+ linkerDeps = append(linkerDeps, deps.LateSharedLibsDeps...)
+
TransformObjToDynamicBinary(ctx, objFiles, sharedLibs,
deps.StaticLibs, deps.LateStaticLibs, deps.WholeStaticLibs,
linkerDeps, deps.CrtBegin, deps.CrtEnd, false, builderFlags, outputFile)
+ if ctx.Device() {
+ // For device targets, optimize out relinking against shared
+ // libraries whose interface hasn't changed by depending on
+ // a table of contents file instead of the library itself.
+ // For host targets, the library might be part of a host tool
+ // that is run during the build, use the library directly so
+ // that the timestamp of the binary changes whenever a library
+ // changes and any necessary tools get re-run.
+ tocPath := outputFile.String()
+ tocPath = pathtools.ReplaceExtension(tocPath, flags.Toolchain.ShlibSuffix()[1:]+".toc")
+ tocFile := android.PathForOutput(ctx, tocPath)
+ library.tocFile = android.OptionalPathForPath(tocFile)
+ TransformSharedObjectToToc(ctx, outputFile, tocFile, builderFlags)
+ }
+
return ret
}
@@ -482,6 +504,10 @@
return library.reuseObjFiles
}
+func (library *libraryDecorator) toc() android.OptionalPath {
+ return library.tocFile
+}
+
func (library *libraryDecorator) install(ctx ModuleContext, file android.Path) {
if !ctx.static() {
library.baseInstaller.install(ctx, file)