diff options
Diffstat (limited to 'arch/ppc/boot/common/string.S')
-rw-r--r-- | arch/ppc/boot/common/string.S | 150 |
1 files changed, 150 insertions, 0 deletions
diff --git a/arch/ppc/boot/common/string.S b/arch/ppc/boot/common/string.S new file mode 100644 index 000000000000..8016e43c4771 --- /dev/null +++ b/arch/ppc/boot/common/string.S @@ -0,0 +1,150 @@ +/* + * String handling functions for PowerPC. + * + * Copyright (C) 1996 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. + */ +#define r0 0 +#define r3 3 +#define r4 4 +#define r5 5 +#define r6 6 +#define r7 7 +#define r8 8 + + .globl strlen +strlen: + addi r4,r3,-1 +1: lbzu r0,1(r4) + cmpwi 0,r0,0 + bne 1b + subf r3,r3,r4 + blr + + .globl memset +memset: + rlwimi r4,r4,8,16,23 + rlwimi r4,r4,16,0,15 + addi r6,r3,-4 + cmplwi 0,r5,4 + blt 7f + stwu r4,4(r6) + beqlr + andi. r0,r6,3 + add r5,r0,r5 + subf r6,r0,r6 + rlwinm r0,r5,32-2,2,31 + mtctr r0 + bdz 6f +1: stwu r4,4(r6) + bdnz 1b +6: andi. r5,r5,3 +7: cmpwi 0,r5,0 + beqlr + mtctr r5 + addi r6,r6,3 +8: stbu r4,1(r6) + bdnz 8b + blr + + .globl memmove +memmove: + cmplw 0,r3,r4 + bgt backwards_memcpy + /* fall through */ + + .globl memcpy +memcpy: + rlwinm. r7,r5,32-3,3,31 /* r0 = r5 >> 3 */ + addi r6,r3,-4 + addi r4,r4,-4 + beq 2f /* if less than 8 bytes to do */ + andi. r0,r6,3 /* get dest word aligned */ + mtctr r7 + bne 5f +1: lwz r7,4(r4) + lwzu r8,8(r4) + stw r7,4(r6) + stwu r8,8(r6) + bdnz 1b + andi. r5,r5,7 +2: cmplwi 0,r5,4 + blt 3f + lwzu r0,4(r4) + addi r5,r5,-4 + stwu r0,4(r6) +3: cmpwi 0,r5,0 + beqlr + mtctr r5 + addi r4,r4,3 + addi r6,r6,3 +4: lbzu r0,1(r4) + stbu r0,1(r6) + bdnz 4b + blr +5: subfic r0,r0,4 + mtctr r0 +6: lbz r7,4(r4) + addi r4,r4,1 + stb r7,4(r6) + addi r6,r6,1 + bdnz 6b + subf r5,r0,r5 + rlwinm. r7,r5,32-3,3,31 + beq 2b + mtctr r7 + b 1b + + .globl backwards_memcpy +backwards_memcpy: + rlwinm. r7,r5,32-3,3,31 /* r0 = r5 >> 3 */ + add r6,r3,r5 + add r4,r4,r5 + beq 2f + andi. r0,r6,3 + mtctr r7 + bne 5f +1: lwz r7,-4(r4) + lwzu r8,-8(r4) + stw r7,-4(r6) + stwu r8,-8(r6) + bdnz 1b + andi. r5,r5,7 +2: cmplwi 0,r5,4 + blt 3f + lwzu r0,-4(r4) + subi r5,r5,4 + stwu r0,-4(r6) +3: cmpwi 0,r5,0 + beqlr + mtctr r5 +4: lbzu r0,-1(r4) + stbu r0,-1(r6) + bdnz 4b + blr +5: mtctr r0 +6: lbzu r7,-1(r4) + stbu r7,-1(r6) + bdnz 6b + subf r5,r0,r5 + rlwinm. r7,r5,32-3,3,31 + beq 2b + mtctr r7 + b 1b + + .globl memcmp +memcmp: + cmpwi 0,r5,0 + blelr + mtctr r5 + addi r6,r3,-1 + addi r4,r4,-1 +1: lbzu r3,1(r6) + lbzu r0,1(r4) + subf. r3,r0,r3 + bdnzt 2,1b + blr |