sparc: refactor sparc64 __mpn_sub_n selector to C

This patch refactors the sparc64 ifunc selector to a C implementation.
Also, the generic symbol is moved to its own implementation file
sub_n-generic.S).

Checked on sparc64-linux-gnu and sparcv9-linux-gnu.

	* sysdeps/sparc/sparc64/multiarch/Makefile (sysdep_routines):
	Add sub_n-generic.
	* sysdeps/sparc/sparc64/multiarch/sub_n-generic.S: New file.
	* sysdeps/sparc/sparc64/multiarch/sub_n.c: Likewise.
	* sysdeps/sparc/sparc64/multiarch/sub_n.S: Remove file.

Signed-off-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>

4 files changed, 31 insertions, 57 deletions

diff --git a/sysdeps/sparc/sparc64/multiarch/Makefile b/sysdeps/sparc/sparc64/multiarch/Makefile
index 2338213600..10fe54f9c0 100644
--- a/sysdeps/sparc/sparc64/multiarch/Makefile
+++ b/sysdeps/sparc/sparc64/multiarch/Makefile
@@ -14,7 +14,7 @@ endif
 
 ifeq ($(subdir),stdlib)
 sysdep_routines += mul_1-vis3 mul_1-generic addmul_1-vis3 submul_1-vis3 \
-		   add_n-vis3 sub_n-vis3 
+		   add_n-vis3 sub_n-vis3 sub_n-generic
 endif
 
 ifeq ($(subdir),math)
diff --git a/sysdeps/sparc/sparc64/multiarch/sub_n-generic.S b/sysdeps/sparc/sparc64/multiarch/sub_n-generic.S
new file mode 100644
index 0000000000..7cece934a7
--- /dev/null
+++ b/sysdeps/sparc/sparc64/multiarch/sub_n-generic.S
@@ -0,0 +1,2 @@
+#define __mpn_sub_n __mpn_sub_n_generic
+#include <sysdeps/sparc/sparc64/sub_n.S>
diff --git a/sysdeps/sparc/sparc64/multiarch/sub_n.S b/sysdeps/sparc/sparc64/multiarch/sub_n.S
deleted file mode 100644
index d20a286df1..0000000000
--- a/sysdeps/sparc/sparc64/multiarch/sub_n.S
+++ /dev/null
@@ -1,56 +0,0 @@
-/* Multiple versions of sub_n
-
-   Copyright (C) 2013-2017 Free Software Foundation, Inc.
-   Contributed by David S. Miller (davem@davemloft.net)
-   This file is part of the GNU C Library.
-
-   The GNU C Library is free software; you can redistribute it and/or
-   modify it under the terms of the GNU Lesser General Public
-   License as published by the Free Software Foundation; either
-   version 2.1 of the License, or (at your option) any later version.
-
-   The GNU C Library is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-   Lesser General Public License for more details.
-
-   You should have received a copy of the GNU Lesser General Public
-   License along with the GNU C Library; if not, see
-   <http://www.gnu.org/licenses/>.  */
-
-#include <sysdep.h>
-
-ENTRY(__mpn_sub_n)
-	.type	__mpn_sub_n, @gnu_indirect_function
-# ifdef SHARED
-	SETUP_PIC_REG_LEAF(o3, o5)
-# endif
-	set	HWCAP_SPARC_VIS3, %o1
-	andcc	%o0, %o1, %g0
-	be	1f
-	 nop
-# ifdef SHARED
-	sethi	%gdop_hix22(__mpn_sub_n_vis3), %o1
-	xor	%o1, %gdop_lox10(__mpn_sub_n_vis3), %o1
-# else
-	set	__mpn_sub_n_vis3, %o1
-# endif
-	ba	10f
-	 nop
-1:
-# ifdef SHARED
-	sethi	%gdop_hix22(__mpn_sub_n_generic), %o1
-	xor	%o1, %gdop_lox10(__mpn_sub_n_generic), %o1
-# else
-	set	__mpn_sub_n_generic, %o1
-# endif
-10:
-# ifdef SHARED
-	add	%o3, %o1, %o1
-# endif
-	retl
-	 mov	%o1, %o0
-END(__mpn_sub_n)
-
-#define __mpn_sub_n __mpn_sub_n_generic
-#include "../sub_n.S"
diff --git a/sysdeps/sparc/sparc64/multiarch/sub_n.c b/sysdeps/sparc/sparc64/multiarch/sub_n.c
new file mode 100644
index 0000000000..758879aaff
--- /dev/null
+++ b/sysdeps/sparc/sparc64/multiarch/sub_n.c
@@ -0,0 +1,28 @@
+/* __mpn_sub_n ifunc resolver, Linux/sparc64 version.
+   Copyright (C) 2017 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <gmp.h>
+#include <sparc-ifunc.h>
+
+extern __typeof (mpn_sub_n) __mpn_sub_n_vis3 attribute_hidden;
+extern __typeof (mpn_sub_n) __mpn_sub_n_generic attribute_hidden;
+
+sparc_libm_ifunc (__mpn_sub_n,
+		  hwcap & HWCAP_SPARC_VIS3
+		  ? __mpn_sub_n_vis3
+		  : __mpn_sub_n_generic)