summaryrefslogtreecommitdiffstats
path: root/arch/ia64/lib/strnlen_user.S
diff options
context:
space:
mode:
Diffstat (limited to 'arch/ia64/lib/strnlen_user.S')
-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
new file mode 100644
index 000000000000..d09066b1e49d
--- /dev/null
+++ b/arch/ia64/lib/strnlen_user.S
@@ -0,0 +1,45 @@
+/*
+ * 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)