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-rw-r--r--arch/ia64/lib/strnlen_user.S45
1 files changed, 45 insertions, 0 deletions
diff --git a/arch/ia64/lib/strnlen_user.S b/arch/ia64/lib/strnlen_user.S
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index 000000000000..d09066b1e49d
--- /dev/null
+++ b/arch/ia64/lib/strnlen_user.S
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+/*
+ * Returns 0 if exception before NUL or reaching the supplied limit (N),
+ * a value greater than N if the string is longer than the limit, else
+ * strlen.
+ *
+ * Inputs:
+ *	in0:	address of buffer
+ *	in1:	string length limit N
+ * Outputs:
+ *	r8:	0 in case of fault, strlen(buffer)+1 otherwise
+ *
+ * Copyright (C) 1999, 2001 David Mosberger-Tang <davidm@hpl.hp.com>
+ */
+
+#include <asm/asmmacro.h>
+
+GLOBAL_ENTRY(__strnlen_user)
+	.prologue
+	alloc r2=ar.pfs,2,0,0,0
+	.save ar.lc, r16
+	mov r16=ar.lc			// preserve ar.lc
+
+	.body
+
+	add r3=-1,in1
+	;;
+	mov ar.lc=r3
+	mov r9=0
+	;;
+	// XXX braindead strlen loop---this needs to be optimized
+.Loop1:
+	EXCLR(.Lexit, ld1 r8=[in0],1)
+	add r9=1,r9
+	;;
+	cmp.eq p6,p0=r8,r0
+(p6)	br.cond.dpnt .Lexit
+	br.cloop.dptk.few .Loop1
+
+	add r9=1,in1			// NUL not found---return N+1
+	;;
+.Lexit:
+	mov r8=r9
+	mov ar.lc=r16			// restore ar.lc
+	br.ret.sptk.many rp
+END(__strnlen_user)