Add sort_bss_symbols_by_size property for shared libs
If sort_bss_symbols_by_size is true, a shared library is built twice.
The first build generates an unsorted output file, which is used to
generate the symbol ordering file. The output of the second build is
a shared library with its bss symbols sorted by their size.
With this, the only user of symbol_ordering_file, libc, is migrated to
use the new property, so we remove symbol_ordering_file support as well.
Bug: 135754984
Test: Build and check the resulting libc.so has its bss symbols sorted.
Change-Id: I5c892b44d82eb99cbc070cfa2c680be3087f3364
diff --git a/cc/library.go b/cc/library.go
index 7cbfdb5..2b7c9a1 100644
--- a/cc/library.go
+++ b/cc/library.go
@@ -110,6 +110,9 @@
// Symbol tags that should be ignored from the symbol file
Exclude_symbol_tags []string
}
+
+ // Order symbols in .bss section by their sizes. Only useful for shared libraries.
+ Sort_bss_symbols_by_size *bool
}
type LibraryMutatedProperties struct {
@@ -758,6 +761,18 @@
linkerDeps = append(linkerDeps, deps.LateSharedLibsDeps...)
linkerDeps = append(linkerDeps, objs.tidyFiles...)
+ if Bool(library.Properties.Sort_bss_symbols_by_size) {
+ unsortedOutputFile := android.PathForModuleOut(ctx, "unsorted", fileName)
+ TransformObjToDynamicBinary(ctx, objs.objFiles, sharedLibs,
+ deps.StaticLibs, deps.LateStaticLibs, deps.WholeStaticLibs,
+ linkerDeps, deps.CrtBegin, deps.CrtEnd, false, builderFlags, unsortedOutputFile, implicitOutputs)
+
+ symbolOrderingFile := android.PathForModuleOut(ctx, "unsorted", fileName+".symbol_order")
+ symbolOrderingFlag := library.baseLinker.sortBssSymbolsBySize(ctx, unsortedOutputFile, symbolOrderingFile, builderFlags)
+ builderFlags.ldFlags += " " + symbolOrderingFlag
+ linkerDeps = append(linkerDeps, symbolOrderingFile)
+ }
+
TransformObjToDynamicBinary(ctx, objs.objFiles, sharedLibs,
deps.StaticLibs, deps.LateStaticLibs, deps.WholeStaticLibs,
linkerDeps, deps.CrtBegin, deps.CrtEnd, false, builderFlags, outputFile, implicitOutputs)