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-rw-r--r--libc/string/avr32/strlen.S62
1 files changed, 62 insertions, 0 deletions
diff --git a/libc/string/avr32/strlen.S b/libc/string/avr32/strlen.S
new file mode 100644
index 000000000..d2808998d
--- /dev/null
+++ b/libc/string/avr32/strlen.S
@@ -0,0 +1,62 @@
+/*
+ * Copyright (C) 2004-2007 Atmel Corporation
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser General
+ * Public License. See the file "COPYING.LIB" in the main directory of this
+ * archive for more details.
+ */
+
+#include <features.h>
+
+#define str r12
+
+ .text
+ .global strlen
+ .type strlen, @function
+strlen:
+ mov r11, r12
+
+ mov r9, str
+ andl r9, 3, COH
+ brne .Lunaligned_str
+
+1: ld.w r8, str++
+ tnbz r8
+ brne 1b
+
+ sub r12, r11
+ bfextu r9, r8, 24, 8
+ cp.w r9, 0
+ subeq r12, 4
+ reteq r12
+ bfextu r9, r8, 16, 8
+ cp.w r9, 0
+ subeq r12, 3
+ reteq r12
+ bfextu r9, r8, 8, 8
+ cp.w r9, 0
+ subeq r12, 2
+ reteq r12
+ sub r12, 1
+ retal r12
+
+.Lunaligned_str:
+ add pc, pc, r9 << 3
+ sub r0, r0, 0 /* 4-byte nop */
+ ld.ub r8, str++
+ sub r8, r8, 0
+ breq 1f
+ ld.ub r8, str++
+ sub r8, r8, 0
+ breq 1f
+ ld.ub r8, str++
+ sub r8, r8, 0
+ brne 1b
+
+1: sub r12, 1
+ sub r12, r11
+ retal r12
+
+ .size strlen, . - strlen
+
+libc_hidden_def(strlen)