[google][4.8] Expose all target specific builtins unconditionally for LIPO builds

[Sriraman Tallam]

The following test-case fails in LIPO mode during profile-use build:

main.cc
------------
__attribute__((target("sse4.2")))
unsigned int problem_aux (unsigned int A, unsigned int B);


int main (int argc, char *argv[])
{
  return problem_aux (0, 0);
}

aux.cc
---------
__attribute__((target("sse4.2")))
unsigned int problem_aux (unsigned int A, unsigned int B)
{
  return __builtin_ia32_crc32qi (A, B);
}

$ g++ -O2 -fprofile-generate main.cc aux.cc
$ ./a.out
$ g++ -O2 -fprofile-use main.cc
error: '__builtin_ia32_crc32qi' was not declared in this scope

This happens when parsing the auxiliary module. __builtin_ia32_crc32qi
is a target specific builtin that gets created after the target
attribute is seen in the declaration of problem_aux in the primary
module. This is too late for adding theisbuiltin to the list of
knowns, the buitlins get saved when cp_save_built_in_decl_pre_parsing
in cp/cp-objcp-common.c is called much earlier.  Hence, this builtin
which is created during primary module parsing is not available when
parsing the auxiliary module.

A simple fix is to expose all target builtins unconditionally in LIPO
mode. Patch:


Index: config/i386/i386.c
===================================================================
--- config/i386/i386.c  (revision 201046)
+++ config/i386/i386.c  (working copy)
@@ -26957,7 +26957,8 @@ def_builtin (HOST_WIDE_INT mask, const char *name,
       ix86_builtins_isa[(int) code].isa = mask;

       mask &= ~OPTION_MASK_ISA_64BIT;
-      if (mask == 0
+      if (flag_dyn_ipa
+         || mask == 0
          || (mask & ix86_isa_flags) != 0
          || (lang_hooks.builtin_function
              == lang_hooks.builtin_function_ext_scope))


Is this ok?

Thanks
Sri