1 files changed, 77 insertions, 0 deletions
diff --git a/ports/sysdeps/powerpc/powerpc32/405/strlen.S b/ports/sysdeps/powerpc/powerpc32/405/strlen.S
new file mode 100644
index 0000000000..210a3afd92
--- /dev/null
+++ b/ports/sysdeps/powerpc/powerpc32/405/strlen.S
@@ -0,0 +1,77 @@
+/* Optimized strlen implementation for PowerPC476.
+   Copyright (C) 2010 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library.  If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <sysdep.h>
+#include <bp-sym.h>
+#include <bp-asm.h>
+
+/* strlen
+
+       Register Use
+       r3:source address and return length of string
+       r4:byte counter
+
+       Implementation description
+       Load 2 words at a time and count bytes, if we find null we subtract one from
+       the count and return the count value. We need to subtract one because
+       we don't count the null character as a byte. */
+
+EALIGN (BP_SYM (strlen),5,0)
+       neg     r7,r3
+       clrlwi. r8,r7,29
+       addi    r4,0,0
+       beq     L(byte_count_loop)
+       mtctr   r8
+
+L(loop):
+       lbz     r5,0(r3)
+       cmpi    cr5,r5,0x0
+       addi    r3,r3,0x1
+       addi    r4,r4,0x1
+       beq     cr5,L(end_strlen)
+       bdnz    L(loop)
+
+L(byte_count_loop):
+       lwz     r5,0(r3)
+       lwz     r6,4(r3)
+       dlmzb.  r12,r5,r6
+       add     r4,r4,r12
+       bne     L(end_strlen)
+       lwz     r5,8(r3)
+       lwz     r6,12(r3)
+       dlmzb.  r12,r5,r6
+       add     r4,r4,r12
+       bne     L(end_strlen)
+       lwz     r5,16(r3)
+       lwz     r6,20(r3)
+       dlmzb.  r12,r5,r6
+       add     r4,r4,r12
+       bne     L(end_strlen)
+       lwz     r5,24(r3)
+       lwz     r6,28(r3)
+       addi    r3,r3,0x20
+       dlmzb.  r12,r5,r6
+       add     r4,r4,r12
+       bne     L(end_strlen)
+       b       L(byte_count_loop)
+
+L(end_strlen):
+       addi    r3,r4,-1
+       blr
+END (BP_SYM (strlen))
+libc_hidden_builtin_def (strlen)