[PAC][Driver] Support ptrauth flags only on ARM64 Darwin

Most ptrauth flags are ABI-affecting, so they should not be exposed to
end users. Under certain conditions, some ptrauth driver flags are intended
to be used for ARM64 Darwin, so allow them in this case.

Leave `-faarch64-jump-table-hardening` available for all AArch64 targets
since it's not ABI-affecting.

Author: kovdan01

clang/lib/Driver/ToolChains/Clang.cpp

@@ -1662,34 +1662,6 @@ void Clang::AddAArch64TargetArgs(const ArgList &Args,
 
   AddUnalignedAccessWarning(CmdArgs);
 
-  Args.addOptInFlag(CmdArgs, options::OPT_fptrauth_intrinsics,
-                    options::OPT_fno_ptrauth_intrinsics);
-  Args.addOptInFlag(CmdArgs, options::OPT_fptrauth_calls,
-                    options::OPT_fno_ptrauth_calls);
-  Args.addOptInFlag(CmdArgs, options::OPT_fptrauth_returns,
-                    options::OPT_fno_ptrauth_returns);
-  Args.addOptInFlag(CmdArgs, options::OPT_fptrauth_auth_traps,
-                    options::OPT_fno_ptrauth_auth_traps);
-  Args.addOptInFlag(
-      CmdArgs, options::OPT_fptrauth_vtable_pointer_address_discrimination,
-      options::OPT_fno_ptrauth_vtable_pointer_address_discrimination);
-  Args.addOptInFlag(
-      CmdArgs, options::OPT_fptrauth_vtable_pointer_type_discrimination,
-      options::OPT_fno_ptrauth_vtable_pointer_type_discrimination);
-  Args.addOptInFlag(
-      CmdArgs, options::OPT_fptrauth_type_info_vtable_pointer_discrimination,
-      options::OPT_fno_ptrauth_type_info_vtable_pointer_discrimination);
-  Args.addOptInFlag(
-      CmdArgs, options::OPT_fptrauth_function_pointer_type_discrimination,
-      options::OPT_fno_ptrauth_function_pointer_type_discrimination);
-
-  Args.addOptInFlag(CmdArgs, options::OPT_fptrauth_indirect_gotos,
-                    options::OPT_fno_ptrauth_indirect_gotos);
-  Args.addOptInFlag(CmdArgs, options::OPT_fptrauth_init_fini,
-                    options::OPT_fno_ptrauth_init_fini);
-  Args.addOptInFlag(CmdArgs,
-                    options::OPT_fptrauth_init_fini_address_discrimination,
-                    options::OPT_fno_ptrauth_init_fini_address_discrimination);
   Args.addOptInFlag(CmdArgs, options::OPT_faarch64_jump_table_hardening,
                     options::OPT_fno_aarch64_jump_table_hardening);
 

clang/lib/Driver/ToolChains/Linux.cpp

@@ -484,49 +484,16 @@ std::string Linux::ComputeEffectiveClangTriple(const llvm::opt::ArgList &Args,
 // options represent the default signing schema.
 static void handlePAuthABI(const Driver &D, const ArgList &DriverArgs,
                            ArgStringList &CC1Args) {
-  if (!DriverArgs.hasArg(options::OPT_fptrauth_intrinsics,
-                         options::OPT_fno_ptrauth_intrinsics))
-    CC1Args.push_back("-fptrauth-intrinsics");
-
-  if (!DriverArgs.hasArg(options::OPT_fptrauth_calls,
-                         options::OPT_fno_ptrauth_calls))
-    CC1Args.push_back("-fptrauth-calls");
-
-  if (!DriverArgs.hasArg(options::OPT_fptrauth_returns,
-                         options::OPT_fno_ptrauth_returns))
-    CC1Args.push_back("-fptrauth-returns");
-
-  if (!DriverArgs.hasArg(options::OPT_fptrauth_auth_traps,
-                         options::OPT_fno_ptrauth_auth_traps))
-    CC1Args.push_back("-fptrauth-auth-traps");
-
-  if (!DriverArgs.hasArg(
-          options::OPT_fptrauth_vtable_pointer_address_discrimination,
-          options::OPT_fno_ptrauth_vtable_pointer_address_discrimination))
-    CC1Args.push_back("-fptrauth-vtable-pointer-address-discrimination");
-
-  if (!DriverArgs.hasArg(
-          options::OPT_fptrauth_vtable_pointer_type_discrimination,
-          options::OPT_fno_ptrauth_vtable_pointer_type_discrimination))
-    CC1Args.push_back("-fptrauth-vtable-pointer-type-discrimination");
-
-  if (!DriverArgs.hasArg(
-          options::OPT_fptrauth_type_info_vtable_pointer_discrimination,
-          options::OPT_fno_ptrauth_type_info_vtable_pointer_discrimination))
-    CC1Args.push_back("-fptrauth-type-info-vtable-pointer-discrimination");
-
-  if (!DriverArgs.hasArg(options::OPT_fptrauth_indirect_gotos,
-                         options::OPT_fno_ptrauth_indirect_gotos))
-    CC1Args.push_back("-fptrauth-indirect-gotos");
-
-  if (!DriverArgs.hasArg(options::OPT_fptrauth_init_fini,
-                         options::OPT_fno_ptrauth_init_fini))
-    CC1Args.push_back("-fptrauth-init-fini");
-
-  if (!DriverArgs.hasArg(
-          options::OPT_fptrauth_init_fini_address_discrimination,
-          options::OPT_fno_ptrauth_init_fini_address_discrimination))
-    CC1Args.push_back("-fptrauth-init-fini-address-discrimination");
+  CC1Args.push_back("-fptrauth-intrinsics");
+  CC1Args.push_back("-fptrauth-calls");
+  CC1Args.push_back("-fptrauth-returns");
+  CC1Args.push_back("-fptrauth-auth-traps");
+  CC1Args.push_back("-fptrauth-vtable-pointer-address-discrimination");
+  CC1Args.push_back("-fptrauth-vtable-pointer-type-discrimination");
+  CC1Args.push_back("-fptrauth-type-info-vtable-pointer-discrimination");
+  CC1Args.push_back("-fptrauth-indirect-gotos");
+  CC1Args.push_back("-fptrauth-init-fini");
+  CC1Args.push_back("-fptrauth-init-fini-address-discrimination");
 
   if (!DriverArgs.hasArg(options::OPT_faarch64_jump_table_hardening,
                          options::OPT_fno_aarch64_jump_table_hardening))