summaryrefslogtreecommitdiff
path: root/sysdeps/powerpc/powerpc32/rshift.S
diff options
context:
space:
mode:
Diffstat (limited to 'sysdeps/powerpc/powerpc32/rshift.S')
-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
new file mode 100644
index 0000000000..498b6c4a88
--- /dev/null
+++ b/sysdeps/powerpc/powerpc32/rshift.S
@@ -0,0 +1,63 @@
+/* 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))