https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91287
--- Comment #28 from Xiong Hu XS Luo <luoxhu at cn dot ibm.com> ---
(In reply to Richard Biener from comment #24)
> Btw, this is controlled by symtab_node::output_to_lto_symbol_table_p which
> has
>
> /* FIXME: Builtins corresponding to real functions probably should have
> symbol table entries. */
> if (TREE_CODE (decl) == FUNCTION_DECL && fndecl_built_in_p (decl))
> return false;
>
> we could try to do sth like
>
> if (TREE_CODE (decl) == FUNCTION_DECL
> && (fndecl_built_in_p (decl, BUILT_IN_MD)
> || (fndecl_built_in_p (decl, BUILT_IN_NORMAL)
> && !associated_internal_fn (decl))))
> return false;
>
> but that would still leave us with too many undefineds I guess
> (gcc_unreachable for one).
>
> We do not currently track builtins that do have a library implementation
> (whether that it is used in the end is another thing, but less important).
>
> What we definitely can do is put a whitelist above like via the following
> which also catches the case of definitions of builtins.
>
> Index: gcc/symtab.c
> ===================================================================
> --- gcc/symtab.c (revision 273968)
> +++ gcc/symtab.c (working copy)
> @@ -2375,10 +2375,24 @@ symtab_node::output_to_lto_symbol_table_
> first place. */
> if (VAR_P (decl) && DECL_HARD_REGISTER (decl))
> return false;
> +
> /* FIXME: Builtins corresponding to real functions probably should have
> symbol table entries. */
> - if (TREE_CODE (decl) == FUNCTION_DECL && fndecl_built_in_p (decl))
> - return false;
> + if (TREE_CODE (decl) == FUNCTION_DECL
> + && !definition
> + && fndecl_built_in_p (decl))
> + {
> + if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL)
> + switch (DECL_FUNCTION_CODE (decl))
> + {
> + CASE_FLT_FN (BUILT_IN_ATAN2):
> + CASE_FLT_FN (BUILT_IN_SIN):
> + return true;
> + default:
> + break;
> + }
> + return false;
> + }
>
> /* We have real symbol that should be in symbol table. However try to
> trim
> down the refernces to libraries bit more because linker will otherwise
Hi Richard, no undefineds generated with below code, what's your opinion about
the updated code, please? Thanks.
diff --git a/gcc/lto-streamer-out.c b/gcc/lto-streamer-out.c
index 47a9143ae26..9d42a57b4b6 100644
--- a/gcc/lto-streamer-out.c
+++ b/gcc/lto-streamer-out.c
@@ -2644,7 +2644,10 @@ write_symbol (struct streamer_tree_cache_d *cache,
gcc_checking_assert (TREE_PUBLIC (t)
&& (TREE_CODE (t) != FUNCTION_DECL
- || !fndecl_built_in_p (t))
+ || !fndecl_built_in_p (t, BUILT_IN_MD))
+ && (TREE_CODE (t) != FUNCTION_DECL
+ || !fndecl_built_in_p (t, BUILT_IN_NORMAL)
+ || associated_internal_fn (t) != IFN_LAST)
&& !DECL_ABSTRACT_P (t)
&& (!VAR_P (t) || !DECL_HARD_REGISTER (t)));
diff --git a/gcc/symtab.c b/gcc/symtab.c
index 63e2820eb93..ce74589b291 100644
--- a/gcc/symtab.c
+++ b/gcc/symtab.c
@@ -2377,7 +2377,10 @@ symtab_node::output_to_lto_symbol_table_p (void)
return false;
/* FIXME: Builtins corresponding to real functions probably should have
symbol table entries. */
- if (TREE_CODE (decl) == FUNCTION_DECL && fndecl_built_in_p (decl))
+ if (TREE_CODE (decl) == FUNCTION_DECL
+ && (fndecl_built_in_p (decl, BUILT_IN_MD)
+ || (fndecl_built_in_p (decl, BUILT_IN_NORMAL)
+ && IFN_LAST == associated_internal_fn (decl))))
return false;
/* We have real symbol that should be in symbol table. However try to trim
