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-rw-r--r--sysdeps/powerpc/powerpc32/rshift.S63
1 files changed, 63 insertions, 0 deletions
diff --git a/sysdeps/powerpc/powerpc32/rshift.S b/sysdeps/powerpc/powerpc32/rshift.S
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+/* Shift a limb right, low level routine.
+   Copyright (C) 1995, 1997, 1999, 2000 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, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <sysdep.h>
+#include <bp-sym.h>
+#include <bp-asm.h>
+
+/* INPUT PARAMETERS
+   res_ptr	r3
+   s1_ptr	r4
+   size		r5
+   cnt		r6  */
+
+ENTRY (BP_SYM (__mpn_rshift))
+#if __BOUNDED_POINTERS__
+	slwi r10,r5,2		/* convert limbs to bytes */
+	CHECK_BOUNDS_BOTH_WIDE (r3, r8, r9, r10)
+	CHECK_BOUNDS_BOTH_WIDE (r4, r8, r9, r10)
+#endif
+	mtctr	r5		# copy size into CTR
+	addi	r7,r3,-4	# move adjusted res_ptr to free return reg
+	subfic	r8,r6,32
+	lwz	r11,0(r4)	# load first s1 limb
+	slw	r3,r11,r8	# compute function return value
+	bdz	L(1)
+
+L(0):	lwzu	r10,4(r4)
+	srw	r9,r11,r6
+	slw	r12,r10,r8
+	or	r9,r9,r12
+	stwu	r9,4(r7)
+	bdz	L(2)
+	lwzu	r11,4(r4)
+	srw	r9,r10,r6
+	slw	r12,r11,r8
+	or	r9,r9,r12
+	stwu	r9,4(r7)
+	bdnz	L(0)
+
+L(1):	srw	r0,r11,r6
+	stw	r0,4(r7)
+	blr
+
+L(2):	srw	r0,r10,r6
+	stw	r0,4(r7)
+	blr
+END (BP_SYM (__mpn_rshift))