Add whole-program vtable optimization feature to Clang.
This patch introduces the -fwhole-program-vtables flag, which enables the
whole-program vtable optimization feature (D16795) in Clang.
Differential Revision: http://reviews.llvm.org/D16821
llvm-svn: 261767
diff --git a/clang/lib/Driver/Tools.cpp b/clang/lib/Driver/Tools.cpp
index 00128dc..0206281 100644
--- a/clang/lib/Driver/Tools.cpp
+++ b/clang/lib/Driver/Tools.cpp
@@ -4270,6 +4270,32 @@
CmdArgs.push_back("-ffunction-sections");
}
+ if (Args.hasArg(options::OPT_fwhole_program_vtables,
+ options::OPT_fno_whole_program_vtables, false)) {
+ if (!D.isUsingLTO())
+ D.Diag(diag::err_drv_argument_only_allowed_with)
+ << "-fwhole-program-vtables"
+ << "-flto";
+ CmdArgs.push_back("-fwhole-program-vtables");
+
+ clang::SmallString<64> Path(D.ResourceDir);
+ llvm::sys::path::append(Path, "vtables_blacklist.txt");
+ if (llvm::sys::fs::exists(Path)) {
+ SmallString<64> BlacklistOpt("-fwhole-program-vtables-blacklist=");
+ BlacklistOpt += Path.str();
+ CmdArgs.push_back(Args.MakeArgString(BlacklistOpt));
+ }
+
+ for (const Arg *A :
+ Args.filtered(options::OPT_fwhole_program_vtables_blacklist_EQ)) {
+ A->claim();
+ if (!llvm::sys::fs::exists(A->getValue()))
+ D.Diag(clang::diag::err_drv_no_such_file) << A->getValue();
+ }
+
+ Args.AddAllArgs(CmdArgs, options::OPT_fwhole_program_vtables_blacklist_EQ);
+ }
+
if (Args.hasFlag(options::OPT_fdata_sections, options::OPT_fno_data_sections,
UseSeparateSections)) {
CmdArgs.push_back("-fdata-sections");