aboutsummaryrefslogtreecommitdiff
path: root/arch/ppc64/lib/string.S
diff options
context:
space:
mode:
Diffstat (limited to 'arch/ppc64/lib/string.S')
-rw-r--r--arch/ppc64/lib/string.S285
1 files changed, 285 insertions, 0 deletions
diff --git a/arch/ppc64/lib/string.S b/arch/ppc64/lib/string.S
new file mode 100644
index 00000000000..813587e5c2e
--- /dev/null
+++ b/arch/ppc64/lib/string.S
@@ -0,0 +1,285 @@
+/*
+ * 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.
+ */
+#include <asm/processor.h>
+#include <asm/errno.h>
+#include <asm/ppc_asm.h>
+
+_GLOBAL(strcpy)
+ addi r5,r3,-1
+ addi r4,r4,-1
+1: lbzu r0,1(r4)
+ cmpwi 0,r0,0
+ stbu r0,1(r5)
+ bne 1b
+ blr
+
+_GLOBAL(strncpy)
+ cmpwi 0,r5,0
+ beqlr
+ mtctr r5
+ addi r6,r3,-1
+ addi r4,r4,-1
+1: lbzu r0,1(r4)
+ cmpwi 0,r0,0
+ stbu r0,1(r6)
+ bdnzf 2,1b /* dec ctr, branch if ctr != 0 && !cr0.eq */
+ blr
+
+_GLOBAL(strcat)
+ addi r5,r3,-1
+ addi r4,r4,-1
+1: lbzu r0,1(r5)
+ cmpwi 0,r0,0
+ bne 1b
+ addi r5,r5,-1
+1: lbzu r0,1(r4)
+ cmpwi 0,r0,0
+ stbu r0,1(r5)
+ bne 1b
+ blr
+
+_GLOBAL(strcmp)
+ addi r5,r3,-1
+ addi r4,r4,-1
+1: lbzu r3,1(r5)
+ cmpwi 1,r3,0
+ lbzu r0,1(r4)
+ subf. r3,r0,r3
+ beqlr 1
+ beq 1b
+ blr
+
+_GLOBAL(strlen)
+ addi r4,r3,-1
+1: lbzu r0,1(r4)
+ cmpwi 0,r0,0
+ bne 1b
+ subf r3,r3,r4
+ blr
+
+_GLOBAL(memset)
+ neg r0,r3
+ rlwimi r4,r4,8,16,23
+ andi. r0,r0,7 /* # bytes to be 8-byte aligned */
+ rlwimi r4,r4,16,0,15
+ cmplw cr1,r5,r0 /* do we get that far? */
+ rldimi r4,r4,32,0
+ mtcrf 1,r0
+ mr r6,r3
+ blt cr1,8f
+ beq+ 3f /* if already 8-byte aligned */
+ subf r5,r0,r5
+ bf 31,1f
+ stb r4,0(r6)
+ addi r6,r6,1
+1: bf 30,2f
+ sth r4,0(r6)
+ addi r6,r6,2
+2: bf 29,3f
+ stw r4,0(r6)
+ addi r6,r6,4
+3: srdi. r0,r5,6
+ clrldi r5,r5,58
+ mtctr r0
+ beq 5f
+4: std r4,0(r6)
+ std r4,8(r6)
+ std r4,16(r6)
+ std r4,24(r6)
+ std r4,32(r6)
+ std r4,40(r6)
+ std r4,48(r6)
+ std r4,56(r6)
+ addi r6,r6,64
+ bdnz 4b
+5: srwi. r0,r5,3
+ clrlwi r5,r5,29
+ mtcrf 1,r0
+ beq 8f
+ bf 29,6f
+ std r4,0(r6)
+ std r4,8(r6)
+ std r4,16(r6)
+ std r4,24(r6)
+ addi r6,r6,32
+6: bf 30,7f
+ std r4,0(r6)
+ std r4,8(r6)
+ addi r6,r6,16
+7: bf 31,8f
+ std r4,0(r6)
+ addi r6,r6,8
+8: cmpwi r5,0
+ mtcrf 1,r5
+ beqlr+
+ bf 29,9f
+ stw r4,0(r6)
+ addi r6,r6,4
+9: bf 30,10f
+ sth r4,0(r6)
+ addi r6,r6,2
+10: bflr 31
+ stb r4,0(r6)
+ blr
+
+_GLOBAL(memmove)
+ cmplw 0,r3,r4
+ bgt .backwards_memcpy
+ b .memcpy
+
+_GLOBAL(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
+
+_GLOBAL(memcmp)
+ cmpwi 0,r5,0
+ ble- 2f
+ 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
+2: li r3,0
+ blr
+
+_GLOBAL(memchr)
+ cmpwi 0,r5,0
+ ble- 2f
+ mtctr r5
+ addi r3,r3,-1
+1: lbzu r0,1(r3)
+ cmpw 0,r0,r4
+ bdnzf 2,1b
+ beqlr
+2: li r3,0
+ blr
+
+_GLOBAL(__clear_user)
+ addi r6,r3,-4
+ li r3,0
+ li r5,0
+ cmplwi 0,r4,4
+ blt 7f
+ /* clear a single word */
+11: stwu r5,4(r6)
+ beqlr
+ /* clear word sized chunks */
+ andi. r0,r6,3
+ add r4,r0,r4
+ subf r6,r0,r6
+ srwi r0,r4,2
+ andi. r4,r4,3
+ mtctr r0
+ bdz 7f
+1: stwu r5,4(r6)
+ bdnz 1b
+ /* clear byte sized chunks */
+7: cmpwi 0,r4,0
+ beqlr
+ mtctr r4
+ addi r6,r6,3
+8: stbu r5,1(r6)
+ bdnz 8b
+ blr
+90: mr r3,r4
+ blr
+91: mfctr r3
+ slwi r3,r3,2
+ add r3,r3,r4
+ blr
+92: mfctr r3
+ blr
+
+ .section __ex_table,"a"
+ .align 3
+ .llong 11b,90b
+ .llong 1b,91b
+ .llong 8b,92b
+ .text
+
+/* r3 = dst, r4 = src, r5 = count */
+_GLOBAL(__strncpy_from_user)
+ addi r6,r3,-1
+ addi r4,r4,-1
+ cmpwi 0,r5,0
+ beq 2f
+ mtctr r5
+1: lbzu r0,1(r4)
+ cmpwi 0,r0,0
+ stbu r0,1(r6)
+ bdnzf 2,1b /* dec ctr, branch if ctr != 0 && !cr0.eq */
+ beq 3f
+2: addi r6,r6,1
+3: subf r3,r3,r6
+ blr
+99: li r3,-EFAULT
+ blr
+
+ .section __ex_table,"a"
+ .align 3
+ .llong 1b,99b
+ .text
+
+/* r3 = str, r4 = len (> 0) */
+_GLOBAL(__strnlen_user)
+ addi r7,r3,-1
+ mtctr r4 /* ctr = len */
+1: lbzu r0,1(r7) /* get next byte */
+ cmpwi 0,r0,0
+ bdnzf 2,1b /* loop if --ctr != 0 && byte != 0 */
+ addi r7,r7,1
+ subf r3,r3,r7 /* number of bytes we have looked at */
+ beqlr /* return if we found a 0 byte */
+ cmpw 0,r3,r4 /* did we look at all len bytes? */
+ blt 99f /* if not, must have hit top */
+ addi r3,r4,1 /* return len + 1 to indicate no null found */
+ blr
+99: li r3,0 /* bad address, return 0 */
+ blr
+
+ .section __ex_table,"a"
+ .align 3
+ .llong 1b,99b