re PR middle-end/20983 (varargs functions force va_list variable to stack unnecessarily)

	PR middle-end/20983
	* tree-ssa-ccp.c (optimize_stdarg_builtin): New function.
	(execute_fold_all_builtins): Call it for BUILT_IN_VA_START,
	BUILT_IN_VA_COPY and BUILT_IN_VA_END.

	* target.h (struct ggc_target): Add expand_builtin_va_start
	hook.
	* target-def.h (TARGET_EXPAND_BUILTIN_VA_START): Define.
	(TARGET_INITIALIZER): Add it.
	* builtins.c (expand_builtin_va_start): Use
	targetm.expand_builtin_va_start hook instead of
	EXPAND_BUILTIN_VA_START macro.
	* alpha/alpha.c (alpha_va_start): Made static.
	(override_options): Clear targetm.expand_builtin_va_start if
	TARGET_UNICOSMK.
	(TARGET_EXPAND_BUILTIN_VA_START): Define.
	* alpha/unicosmk.h (EXPAND_BUILTIN_VA_START): Remove.
	* alpha/alpha.h (EXPAND_BUILTIN_VA_START): Remove.
	* alpha/alpha-protos.h (alpha_va_start): Remove prototype.
	* xtensa/xtensa.h (EXPAND_BUILTIN_VA_START): Remove.
	* xtensa/xtensa.c (TARGET_EXPAND_BUILTIN_VA_START): Define.
	(xtensa_va_start): Made static.
	* xtensa/xtensa-protos.h (xtensa_va_start): Remove prototype.
	* pa/pa-protos.h (hppa_va_start): Remove prototype.
	* pa/pa.h (EXPAND_BUILTIN_VA_START): Remove.
	* pa/pa.c (hppa_va_start): Made static, add prototype.
	(TARGET_EXPAND_BUILTIN_VA_START): Define.
	* frv/frv.c (frv_expand_builtin_va_start): Made static, add prototype.
	(TARGET_EXPAND_BUILTIN_VA_START): Define.
	* frv/frv-protos.h (frv_expand_builtin_va_start): Remove prototype.
	* frv/frv.h (EXPAND_BUILTIN_VA_START): Remove.
	* i386/i386.c (override_options): Clear
	targetm.expand_builtin_va_start if -m32 or 64-bit MS ABI.
	(ix86_va_start): Made static.
	(TARGET_EXPAND_BUILTIN_VA_START): Define.
	* i386/i386.h (EXPAND_BUILTIN_VA_START): Remove.
	* i386/i386-protos.h (ix86_va_start, ix86_va_arg): Remove prototypes.
	* iq2000/iq2000-protos.h (iq2000_va_start): Remove prototype.
	* iq2000/iq2000.h (EXPAND_BUILTIN_VA_START): Remove.
	* iq2000/iq2000.c (iq2000_va_start): Made static, add prototype.
	(TARGET_EXPAND_BUILTIN_VA_START): Define.
	* rs6000/rs6000-protos.h (rs6000_va_start): Remove prototype.
	* rs6000/rs6000.c (rs6000_va_start): Made static, add prototype.
	(TARGET_EXPAND_BUILTIN_VA_START): Define.
	(rs6000_override_options): Clear targetm.expand_builtin_va_start if
	DEFAULT_ABI != ABI_V4.
	* rs6000/rs6000.h (EXPAND_BUILTIN_VA_START): Remove.
	* spu/spu.c (spu_va_start): Made static, add prototype.
	(TARGET_EXPAND_BUILTIN_VA_START): Define.
	* spu/spu.h (EXPAND_BUILTIN_VA_START): Remove.
	* spu/spu-protos.h spu_va_start): Remove prototype.
	* stormy16/stormy16.h (EXPAND_BUILTIN_VA_START): Remove.
	* stormy16/stormy16-protos.h (xstormy16_expand_builtin_va_start):
	Remove prototype.
	* stormy16/stormy16.c (xstormy16_expand_builtin_va_start): Made
	static.
	(TARGET_EXPAND_BUILTIN_VA_START): Define.
	* s390/s390-protos.h (s390_va_start): Remove prototype.
	* s390/s390.c (s390_va_start): Made static.
	(TARGET_EXPAND_BUILTIN_VA_START): Define.
	* s390/s390.h (EXPAND_BUILTIN_VA_START): Remove.
	* mn10300/mn10300.h (EXPAND_BUILTIN_VA_START): Remove.
	* mn10300/mn10300-protos.h (mn10300_va_start): Remove prototype.
	* mn10300/mn10300.c (mn10300_va_start): Made static, add prototype.
	(TARGET_EXPAND_BUILTIN_VA_START): Define.
	* arc/arc.c (arc_va_start): Made static, add prototype.
	(TARGET_EXPAND_BUILTIN_VA_START): Define.
	* arc/arc.h (EXPAND_BUILTIN_VA_START): Remove.
	* arc/arc-protos.h (arc_va_start): Remove prototype.
	* mt/mt-protos.h (mt_va_start): Remove prototype.
	* sparc/sparc.c (sparc_va_start): Made static, add prototype.
	(TARGET_EXPAND_BUILTIN_VA_START): Define.
	* sparc/sparc-protos.h (sparc_va_start): Remove prototype.
	* sparc/sparc.h (EXPAND_BUILTIN_VA_START): Remove.
	* sh/sh.c (sh_va_start): Made static, add prototype.
	(TARGET_EXPAND_BUILTIN_VA_START): Define.
	* sh/sh-protos.h (sh_va_start): Remove prototype.
	* sh/sh.h (EXPAND_BUILTIN_VA_START): Remove.
	* mips/mips-protos.h (mips_va_start): Remove prototype.
	* mips/mips.h (EXPAND_BUILTIN_VA_START): Remove.
	* mips/mips.c (mips_va_start): Made static.
	(TARGET_EXPAND_BUILTIN_VA_START): Define.

From-SVN: r130650

3 files changed, 5 insertions, 8 deletions

diff --git a/gcc/config/arc/arc-protos.h b/gcc/config/arc/arc-protos.h
index 9eadf35..c9fc51a 100644
--- a/gcc/config/arc/arc-protos.h
+++ b/gcc/config/arc/arc-protos.h
@@ -17,8 +17,6 @@ You should have received a copy of the GNU General Public License
 along with GCC; see the file COPYING3.  If not see
 <http://www.gnu.org/licenses/>.  */
 
-extern void arc_va_start (tree, rtx);
-
 #ifdef RTX_CODE
 extern enum machine_mode arc_select_cc_mode (enum rtx_code, rtx, rtx);
 
diff --git a/gcc/config/arc/arc.c b/gcc/config/arc/arc.c
index a1e04af..5b2e7b8 100644
--- a/gcc/config/arc/arc.c
+++ b/gcc/config/arc/arc.c
@@ -89,6 +89,7 @@ static void arc_output_function_prologue (FILE *, HOST_WIDE_INT);
 static void arc_output_function_epilogue (FILE *, HOST_WIDE_INT);
 static void arc_file_start (void);
 static void arc_internal_label (FILE *, const char *, unsigned long);
+static void arc_va_start (tree, rtx);
 static void arc_setup_incoming_varargs (CUMULATIVE_ARGS *, enum machine_mode,
 					tree, int *, int);
 static bool arc_rtx_costs (rtx, int, int, int *);
@@ -144,6 +145,9 @@ static bool arc_pass_by_reference (CUMULATIVE_ARGS *, enum machine_mode,
 #undef TARGET_SETUP_INCOMING_VARARGS
 #define TARGET_SETUP_INCOMING_VARARGS arc_setup_incoming_varargs
 
+#undef TARGET_EXPAND_BUILTIN_VA_START
+#define TARGET_EXPAND_BUILTIN_VA_START arc_va_start
+
 struct gcc_target targetm = TARGET_INITIALIZER;
 
 /* Implement TARGET_HANDLE_OPTION.  */
@@ -2274,7 +2278,7 @@ arc_ccfsm_record_branch_deleted (void)
   current_insn_set_cc_p = last_insn_set_cc_p;
 }
 
-void
+static void
 arc_va_start (tree valist, rtx nextarg)
 {
   /* See arc_setup_incoming_varargs for reasons for this oddity.  */
diff --git a/gcc/config/arc/arc.h b/gcc/config/arc/arc.h
index 05f4aad..17412fc 100644
--- a/gcc/config/arc/arc.h
+++ b/gcc/config/arc/arc.h
@@ -1086,8 +1086,3 @@ enum arc_function_type {
 #define ARC_INTERRUPT_P(TYPE) \
 ((TYPE) == ARC_FUNCTION_ILINK1 || (TYPE) == ARC_FUNCTION_ILINK2)
 /* Compute the type of a function from its DECL.  */
-
-
-/* Implement `va_start' for varargs and stdarg.  */
-#define EXPAND_BUILTIN_VA_START(valist, nextarg) \
-  arc_va_start (valist, nextarg)