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-rw-r--r--arch/powerpc/lib/string.S203
1 files changed, 203 insertions, 0 deletions
diff --git a/arch/powerpc/lib/string.S b/arch/powerpc/lib/string.S
new file mode 100644
index 000000000000..15d40e9ef8b1
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+++ b/arch/powerpc/lib/string.S
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+/*
+ * 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 <linux/config.h>
+#include <asm/processor.h>
+#include <asm/errno.h>
+#include <asm/ppc_asm.h>
+
+ .text
+ .stabs "arch/powerpc/lib/",N_SO,0,0,0f
+ .stabs "string.S",N_SO,0,0,0f
+0:
+
+ .section __ex_table,"a"
+#ifdef CONFIG_PPC64
+ .align 3
+#define EXTBL .llong
+#else
+ .align 2
+#define EXTBL .long
+#endif
+ .text
+
+_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
+
+/* This clears out any unused part of the destination buffer,
+ just as the libc version does. -- paulus */
+_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 */
+ bnelr /* if we didn't hit a null char, we're done */
+ mfctr r5
+ cmpwi 0,r5,0 /* any space left in destination buffer? */
+ beqlr /* we know r0 == 0 here */
+2: stbu r0,1(r6) /* clear it out if so */
+ bdnz 2b
+ 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(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"
+ EXTBL 11b,90b
+ EXTBL 1b,91b
+ EXTBL 8b,92b
+ .text
+
+_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"
+ EXTBL 1b,99b
+ .text
+
+/* r3 = str, r4 = len (> 0), r5 = top (highest addr) */
+_GLOBAL(__strnlen_user)
+ addi r7,r3,-1
+ subf r6,r7,r5 /* top+1 - str */
+ cmplw 0,r4,r6
+ bge 0f
+ mr r6,r4
+0: mtctr r6 /* ctr = min(len, top - str) */
+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"
+ EXTBL 1b,99b