diff options
Diffstat (limited to 'qemu/roms/openbios/arch/ppc/misc.S')
-rw-r--r-- | qemu/roms/openbios/arch/ppc/misc.S | 74 |
1 files changed, 74 insertions, 0 deletions
diff --git a/qemu/roms/openbios/arch/ppc/misc.S b/qemu/roms/openbios/arch/ppc/misc.S new file mode 100644 index 000000000..435ce0eca --- /dev/null +++ b/qemu/roms/openbios/arch/ppc/misc.S @@ -0,0 +1,74 @@ +/* + * Creation Date: <2002/10/20 15:54:50 samuel> + * Time-stamp: <2002/10/20 15:57:21 samuel> + * + * <misc.S> + * + * Low-level stuff + * + * Copyright (C) 2002, 2003 Samuel Rydh (samuel@ibrium.se) + * + * Based upon misc.S from the the linux kernel with the following + * copyrights: + * + * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org), + * Cort Dougan (cort@cs.nmt.edu), 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 + * + */ + +#include "asm/asmdefs.h" +#include "asm/processor.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): + 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 + +GLOBL(__ashldi3): + subfic r6,r5,32 + slw r3,r3,r5 # MSW = count > 31 ? 0 : MSW << count + addi r7,r5,32 # could be xori, or addi with -32 + srw r6,r4,r6 # t1 = count > 31 ? 0 : LSW >> (32-count) + slw r7,r4,r7 # t2 = count < 32 ? 0 : LSW << (count-32) + or r3,r3,r6 # MSW |= t1 + slw r4,r4,r5 # LSW = LSW << count + or r3,r3,r7 # MSW |= t2 + blr + +GLOBL(__lshrdi3): + 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) + srw r7,r3,r7 # t2 = count < 32 ? 0 : MSW >> (count-32) + or r4,r4,r6 # LSW |= t1 + srw r3,r3,r5 # MSW = MSW >> count + or r4,r4,r7 # LSW |= t2 + blr |