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/binary.go b/cc/binary.go
index 8afce09..083cf0d 100644
--- a/cc/binary.go
+++ b/cc/binary.go
@@ -281,6 +281,9 @@
flagsToBuilderFlags(flags), afterPrefixSymbols)
}
+ 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, true,
builderFlags, outputFile)
diff --git a/cc/builder.go b/cc/builder.go
index 42a7f48..b813783 100644
--- a/cc/builder.go
+++ b/cc/builder.go
@@ -138,6 +138,18 @@
Description: "copy gcc $out",
},
"ccCmd", "cFlags", "libName")
+
+ tocPath = pctx.SourcePathVariable("tocPath", "build/soong/scripts/toc.sh")
+
+ toc = pctx.AndroidStaticRule("toc",
+ blueprint.RuleParams{
+ Depfile: "${out}.d",
+ Deps: blueprint.DepsGCC,
+ Command: "CROSS_COMPILE=$crossCompile $tocPath -i ${in} -o ${out} -d ${out}.d",
+ CommandDeps: []string{"$tocPath"},
+ Restat: true,
+ },
+ "crossCompile")
)
func init() {
@@ -380,7 +392,6 @@
libFlagsList = append(libFlagsList, lib.String())
}
- deps = append(deps, sharedLibs...)
deps = append(deps, staticLibs...)
deps = append(deps, lateStaticLibs...)
deps = append(deps, wholeStaticLibs...)
@@ -403,6 +414,22 @@
})
}
+// Generate a rule for extract a table of contents from a shared library (.so)
+func TransformSharedObjectToToc(ctx android.ModuleContext, inputFile android.WritablePath,
+ outputFile android.WritablePath, flags builderFlags) {
+
+ crossCompile := gccCmd(flags.toolchain, "")
+
+ ctx.ModuleBuild(pctx, android.ModuleBuildParams{
+ Rule: toc,
+ Output: outputFile,
+ Input: inputFile,
+ Args: map[string]string{
+ "crossCompile": crossCompile,
+ },
+ })
+}
+
// Generate a rule for compiling multiple .o files to a .o using ld partial linking
func TransformObjsToObj(ctx android.ModuleContext, objFiles android.Paths,
flags builderFlags, outputFile android.WritablePath) {
diff --git a/cc/cc.go b/cc/cc.go
index 9a19812..75292aa 100644
--- a/cc/cc.go
+++ b/cc/cc.go
@@ -70,18 +70,25 @@
}
type PathDeps struct {
- SharedLibs, LateSharedLibs android.Paths
+ // Paths to .so files
+ SharedLibs, LateSharedLibs android.Paths
+ // Paths to the dependencies to use for .so files (.so.toc files)
+ SharedLibsDeps, LateSharedLibsDeps android.Paths
+ // Paths to .a files
StaticLibs, LateStaticLibs, WholeStaticLibs android.Paths
+ // Paths to .o files
ObjFiles android.Paths
WholeStaticLibObjFiles android.Paths
+ // Paths to generated source files
GeneratedSources android.Paths
GeneratedHeaders android.Paths
Flags, ReexportedFlags []string
ReexportedFlagsDeps android.Paths
+ // Paths to crt*.o files
CrtBegin, CrtEnd android.OptionalPath
}
@@ -815,19 +822,27 @@
checkLinkType(c, cc)
}
+ var ptr *android.Paths
var depPtr *android.Paths
+ linkFile := cc.outputFile
+ depFile := android.OptionalPath{}
+
switch tag {
case ndkStubDepTag, sharedDepTag, sharedExportDepTag:
- depPtr = &depPaths.SharedLibs
+ ptr = &depPaths.SharedLibs
+ depPtr = &depPaths.SharedLibsDeps
+ depFile = cc.linker.(libraryInterface).toc()
case lateSharedDepTag, ndkLateStubDepTag:
- depPtr = &depPaths.LateSharedLibs
+ ptr = &depPaths.LateSharedLibs
+ depPtr = &depPaths.LateSharedLibsDeps
+ depFile = cc.linker.(libraryInterface).toc()
case staticDepTag, staticExportDepTag:
- depPtr = &depPaths.StaticLibs
+ ptr = &depPaths.StaticLibs
case lateStaticDepTag:
- depPtr = &depPaths.LateStaticLibs
+ ptr = &depPaths.LateStaticLibs
case wholeStaticDepTag:
- depPtr = &depPaths.WholeStaticLibs
+ ptr = &depPaths.WholeStaticLibs
staticLib, ok := cc.linker.(libraryInterface)
if !ok || !staticLib.static() {
ctx.ModuleErrorf("module %q not a static library", name)
@@ -844,17 +859,25 @@
depPaths.WholeStaticLibObjFiles =
append(depPaths.WholeStaticLibObjFiles, staticLib.objs()...)
case objDepTag:
- depPtr = &depPaths.ObjFiles
+ ptr = &depPaths.ObjFiles
case crtBeginDepTag:
- depPaths.CrtBegin = cc.outputFile
+ depPaths.CrtBegin = linkFile
case crtEndDepTag:
- depPaths.CrtEnd = cc.outputFile
+ depPaths.CrtEnd = linkFile
default:
panic(fmt.Errorf("unknown dependency tag: %s", tag))
}
+ if ptr != nil {
+ *ptr = append(*ptr, linkFile.Path())
+ }
+
if depPtr != nil {
- *depPtr = append(*depPtr, cc.outputFile.Path())
+ dep := depFile
+ if !dep.Valid() {
+ dep = linkFile
+ }
+ *depPtr = append(*depPtr, dep.Path())
}
})
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)