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- /*
- * This code was copied from arch/powerpc/kernel/misc_32.S in the Linux
- * kernel sources (commit 85e2efbb1db9a18d218006706d6e4fbeb0216213, also
- * known as 2.6.38-rc5). The source file copyrights are as follows:
- *
- * (C) Copyright 1995-1996 Gary Thomas (gdt@linuxppc.org)
- *
- * Largely rewritten by Cort Dougan (cort@cs.nmt.edu)
- * and Paul Mackerras.
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License as
- * published by the Free Software Foundation; either version 2 of
- * the License, or (at your option) any later version.
- */
- #include <ppc_asm.tmpl>
- #include <ppc_defs.h>
- #include <config.h>
- /*
- * Extended precision shifts.
- *
- * Updated to be valid for shift counts from 0 to 63 inclusive.
- * -- Gabriel
- *
- * R3/R4 has 64 bit value
- * R5 has shift count
- * result in R3/R4
- *
- * ashrdi3: arithmetic right shift (sign propagation)
- * lshrdi3: logical right shift
- * ashldi3: left shift
- */
- .globl __ashrdi3
- __ashrdi3:
- subfic r6,r5,32
- srw r4,r4,r5 # LSW = count > 31 ? 0 : LSW >> count
- addi r7,r5,32 # could be xori, or addi with -32
- slw r6,r3,r6 # t1 = count > 31 ? 0 : MSW << (32-count)
- rlwinm r8,r7,0,32 # t3 = (count < 32) ? 32 : 0
- sraw r7,r3,r7 # t2 = MSW >> (count-32)
- or r4,r4,r6 # LSW |= t1
- slw r7,r7,r8 # t2 = (count < 32) ? 0 : t2
- sraw r3,r3,r5 # MSW = MSW >> count
- or r4,r4,r7 # LSW |= t2
- blr
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