patch-2.3.99-pre8 linux/arch/s390/lib/strncpy.S

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diff -u --recursive --new-file v2.3.99-pre7/linux/arch/s390/lib/strncpy.S linux/arch/s390/lib/strncpy.S
@@ -0,0 +1,30 @@
+/*
+ *  arch/s390/kernel/strncpy.S
+ *    S390 strncpy routine
+ *
+ *  S390 version
+ *    Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
+ *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
+ */
+
+/*
+ * R2 = address of destination
+ * R3 = address of source string
+ * R4 = max number of bytes to copy
+ */
+        .globl   strncpy
+strncpy:
+        LR      1,2            # don't touch address in R2
+	LTR     4,4
+        JZ      strncpy_exit   # 0 bytes -> nothing to do
+	SR      0,0
+strncpy_loop:
+        ICM     0,1,0(3)       # ICM sets the cc, IC does not
+	LA      3,1(0,3)
+        STC     0,0(0,1)
+	LA      1,1(0,1)
+        JZ      strncpy_exit   # ICM inserted a 0x00
+        BRCT    4,strncpy_loop # R4 -= 1, jump to strncpy_loop if >  0
+strncpy_exit:
+        BR      14
+

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