2013-01-10 Marcus Shawcroft <marcus.shawcroft@linaro.org>

        * libc/machine/aarch64/Makefile.am (lib_a_SOURCES): Add
        strnlen-stub.c and strnlen.S
        * libc/machine/aarch64/Makefile.in: Regenerated.
        * libc/machine/aarch64/strnlen-stub.c: New file.
        * libc/machine/aarch64/strnlen.S: New file.

4 files changed, 219 insertions, 2 deletions

diff --git a/newlib/libc/machine/aarch64/Makefile.am b/newlib/libc/machine/aarch64/Makefile.am
index d454975d7..21aeed1cd 100644
--- a/newlib/libc/machine/aarch64/Makefile.am
+++ b/newlib/libc/machine/aarch64/Makefile.am
@@ -22,6 +22,8 @@ lib_a_SOURCES += strlen-stub.c
 lib_a_SOURCES += strlen.S
 lib_a_SOURCES += strncmp-stub.c
 lib_a_SOURCES += strncmp.S
+lib_a_SOURCES += strnlen-stub.c
+lib_a_SOURCES += strnlen.S
 
 lib_a_CCASFLAGS=$(AM_CCASFLAGS)
 lib_a_CFLAGS=$(AM_CFLAGS)
diff --git a/newlib/libc/machine/aarch64/Makefile.in b/newlib/libc/machine/aarch64/Makefile.in
index 78a312d34..b5a9724e8 100644
--- a/newlib/libc/machine/aarch64/Makefile.in
+++ b/newlib/libc/machine/aarch64/Makefile.in
@@ -75,7 +75,8 @@ am_lib_a_OBJECTS = lib_a-memcpy-stub.$(OBJEXT) lib_a-memcpy.$(OBJEXT) \
 	lib_a-setjmp.$(OBJEXT) lib_a-strcmp-stub.$(OBJEXT) \
 	lib_a-strcmp.$(OBJEXT) lib_a-strlen-stub.$(OBJEXT) \
 	lib_a-strlen.$(OBJEXT) lib_a-strncmp-stub.$(OBJEXT) \
-	lib_a-strncmp.$(OBJEXT)
+	lib_a-strncmp.$(OBJEXT) lib_a-strnlen-stub.$(OBJEXT) \
+	lib_a-strnlen.$(OBJEXT)
 lib_a_OBJECTS = $(am_lib_a_OBJECTS)
 DEFAULT_INCLUDES = -I.@am__isrc@
 depcomp =
@@ -203,7 +204,8 @@ AM_CCASFLAGS = $(INCLUDES)
 noinst_LIBRARIES = lib.a
 lib_a_SOURCES = memcpy-stub.c memcpy.S memmove-stub.c memmove.S \
 	memset-stub.c memset.S setjmp.S strcmp-stub.c strcmp.S \
-	strlen-stub.c strlen.S strncmp-stub.c strncmp.S
+	strlen-stub.c strlen.S strncmp-stub.c strncmp.S strnlen-stub.c \
+	strnlen.S
 lib_a_CCASFLAGS = $(AM_CCASFLAGS)
 lib_a_CFLAGS = $(AM_CFLAGS)
 ACLOCAL_AMFLAGS = -I ../../.. -I ../../../..
@@ -308,6 +310,12 @@ lib_a-strncmp.o: strncmp.S
 lib_a-strncmp.obj: strncmp.S
 	$(CCAS) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(lib_a_CCASFLAGS) $(CCASFLAGS) -c -o lib_a-strncmp.obj `if test -f 'strncmp.S'; then $(CYGPATH_W) 'strncmp.S'; else $(CYGPATH_W) '$(srcdir)/strncmp.S'; fi`
 
+lib_a-strnlen.o: strnlen.S
+	$(CCAS) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(lib_a_CCASFLAGS) $(CCASFLAGS) -c -o lib_a-strnlen.o `test -f 'strnlen.S' || echo '$(srcdir)/'`strnlen.S
+
+lib_a-strnlen.obj: strnlen.S
+	$(CCAS) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(lib_a_CCASFLAGS) $(CCASFLAGS) -c -o lib_a-strnlen.obj `if test -f 'strnlen.S'; then $(CYGPATH_W) 'strnlen.S'; else $(CYGPATH_W) '$(srcdir)/strnlen.S'; fi`
+
 .c.o:
 	$(COMPILE) -c $<
 
@@ -350,6 +358,12 @@ lib_a-strncmp-stub.o: strncmp-stub.c
 lib_a-strncmp-stub.obj: strncmp-stub.c
 	$(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(lib_a_CFLAGS) $(CFLAGS) -c -o lib_a-strncmp-stub.obj `if test -f 'strncmp-stub.c'; then $(CYGPATH_W) 'strncmp-stub.c'; else $(CYGPATH_W) '$(srcdir)/strncmp-stub.c'; fi`
 
+lib_a-strnlen-stub.o: strnlen-stub.c
+	$(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(lib_a_CFLAGS) $(CFLAGS) -c -o lib_a-strnlen-stub.o `test -f 'strnlen-stub.c' || echo '$(srcdir)/'`strnlen-stub.c
+
+lib_a-strnlen-stub.obj: strnlen-stub.c
+	$(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(lib_a_CFLAGS) $(CFLAGS) -c -o lib_a-strnlen-stub.obj `if test -f 'strnlen-stub.c'; then $(CYGPATH_W) 'strnlen-stub.c'; else $(CYGPATH_W) '$(srcdir)/strnlen-stub.c'; fi`
+
 ID: $(HEADERS) $(SOURCES) $(LISP) $(TAGS_FILES)
 	list='$(SOURCES) $(HEADERS) $(LISP) $(TAGS_FILES)'; \
 	unique=`for i in $$list; do \
diff --git a/newlib/libc/machine/aarch64/strnlen-stub.c b/newlib/libc/machine/aarch64/strnlen-stub.c
new file mode 100644
index 000000000..8e1903c8e
--- /dev/null
+++ b/newlib/libc/machine/aarch64/strnlen-stub.c
@@ -0,0 +1,31 @@
+/* Copyright (c) 2013, Linaro Limited
+   All rights reserved.
+
+   Redistribution and use in source and binary forms, with or without
+   modification, are permitted provided that the following conditions are met:
+       * Redistributions of source code must retain the above copyright
+         notice, this list of conditions and the following disclaimer.
+       * Redistributions in binary form must reproduce the above copyright
+         notice, this list of conditions and the following disclaimer in the
+         documentation and/or other materials provided with the distribution.
+       * Neither the name of the Linaro nor the
+         names of its contributors may be used to endorse or promote products
+         derived from this software without specific prior written permission.
+
+   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+   HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */
+
+#if (defined (__OPTIMIZE_SIZE__) || defined (PREFER_SIZE_OVER_SPEED))
+# include "../../string/strnlen.c"
+#else
+/* See strnlen.S  */
+#endif
diff --git a/newlib/libc/machine/aarch64/strnlen.S b/newlib/libc/machine/aarch64/strnlen.S
new file mode 100644
index 000000000..893163d90
--- /dev/null
+++ b/newlib/libc/machine/aarch64/strnlen.S
@@ -0,0 +1,170 @@
+/* strnlen - calculate the length of a string with limit.
+
+   Copyright (c) 2013, Linaro Limited
+   All rights reserved.
+
+   Redistribution and use in source and binary forms, with or without
+   modification, are permitted provided that the following conditions are met:
+       * Redistributions of source code must retain the above copyright
+         notice, this list of conditions and the following disclaimer.
+       * Redistributions in binary form must reproduce the above copyright
+         notice, this list of conditions and the following disclaimer in the
+         documentation and/or other materials provided with the distribution.
+       * Neither the name of the Linaro nor the
+         names of its contributors may be used to endorse or promote products
+         derived from this software without specific prior written permission.
+
+   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+   HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */
+
+#if (defined (__OPTIMIZE_SIZE__) || defined (PREFER_SIZE_OVER_SPEED))
+/* See strlen-stub.c  */
+#else
+
+/* Assumptions:
+ *
+ * ARMv8-a, AArch64
+ */
+
+/* Arguments and results.  */
+#define srcin		x0
+#define len		x0
+#define limit		x1
+
+/* Locals and temporaries.  */
+#define src		x2
+#define data1		x3
+#define data2		x4
+#define data2a		x5
+#define has_nul1	x6
+#define has_nul2	x7
+#define tmp1		x8
+#define tmp2		x9
+#define tmp3		x10
+#define tmp4		x11
+#define zeroones	x12
+#define pos		x13
+#define limit_wd	x14
+
+	.macro def_fn f p2align=0
+	.text
+	.p2align \p2align
+	.global \f
+	.type \f, %function
+\f:
+	.endm
+
+#define REP8_01 0x0101010101010101
+#define REP8_7f 0x7f7f7f7f7f7f7f7f
+#define REP8_80 0x8080808080808080
+
+	.text
+	.p2align	6
+.Lstart:
+	/* Pre-pad to ensure critical loop begins an icache line.  */
+	.rep 7
+	nop
+	.endr
+	/* Put this code here to avoid wasting more space with pre-padding.  */
+.Lhit_limit:
+	mov	len, limit
+	ret
+
+def_fn strnlen
+	cbz	limit, .Lhit_limit
+	mov	zeroones, #REP8_01
+	bic	src, srcin, #15
+	ands	tmp1, srcin, #15
+	b.ne	.Lmisaligned
+	add	limit_wd, limit, #15
+	lsr	limit_wd, limit_wd, #4
+	/* NUL detection works on the principle that (X - 1) & (~X) & 0x80
+	   (=> (X - 1) & ~(X | 0x7f)) is non-zero iff a byte is zero, and
+	   can be done in parallel across the entire word.  */
+	/* The inner loop deals with two Dwords at a time.  This has a
+	   slightly higher start-up cost, but we should win quite quickly,
+	   especially on cores with a high number of issue slots per
+	   cycle, as we get much better parallelism out of the operations.  */
+
+	/* Start of critial section -- keep to one 64Byte cache line.  */
+.Lloop:
+	ldp	data1, data2, [src], #16
+.Lrealigned:
+	sub	tmp1, data1, zeroones
+	orr	tmp2, data1, #REP8_7f
+	sub	tmp3, data2, zeroones
+	orr	tmp4, data2, #REP8_7f
+	bic	has_nul1, tmp1, tmp2
+	bic	has_nul2, tmp3, tmp4
+	subs	limit_wd, limit_wd, #1
+	orr	tmp1, has_nul1, has_nul2
+	ccmp	tmp1, #0, #0, ne	/* NZCV = 0000  */
+	b.eq	.Lloop
+	/* End of critical section -- keep to one 64Byte cache line.  */
+
+	orr	tmp1, has_nul1, has_nul2
+	cbz	tmp1, .Lhit_limit	/* No null in final Qword.  */
+
+	/* We know there's a null in the final Qword.  The easiest thing
+	   to do now is work out the length of the string and return
+	   MIN (len, limit).  */
+
+	sub	len, src, srcin
+	cbz	has_nul1, .Lnul_in_data2
+#ifdef __AARCH64EB__
+	mov	data2, data1
+#endif
+	sub	len, len, #8
+	mov	has_nul2, has_nul1
+.Lnul_in_data2:
+#ifdef __AARCH64EB__
+	/* For big-endian, carry propagation (if the final byte in the
+	   string is 0x01) means we cannot use has_nul directly.  The
+	   easiest way to get the correct byte is to byte-swap the data
+	   and calculate the syndrome a second time.  */
+	rev	data2, data2
+	sub	tmp1, data2, zeroones
+	orr	tmp2, data2, #REP8_7f
+	bic	has_nul2, tmp1, tmp2
+#endif
+	sub	len, len, #8
+	rev	has_nul2, has_nul2
+	clz	pos, has_nul2
+	add	len, len, pos, lsr #3		/* Bits to bytes.  */
+	cmp	len, limit
+	csel	len, len, limit, ls		/* Return the lower value.  */
+	ret
+
+.Lmisaligned:
+	add	tmp3, limit, tmp1
+	cmp	tmp1, #8
+	neg	tmp1, tmp1
+	ldp	data1, data2, [src], #16
+	add	limit_wd, tmp3, #15
+	lsl	tmp1, tmp1, #3		/* Bytes beyond alignment -> bits.  */
+	mov	tmp2, #~0
+	lsr	limit_wd, limit_wd, #4
+#ifdef __AARCH64EB__
+	/* Big-endian.  Early bytes are at MSB.  */
+	lsl	tmp2, tmp2, tmp1	/* Shift (tmp1 & 63).  */
+#else
+	/* Little-endian.  Early bytes are at LSB.  */
+	lsr	tmp2, tmp2, tmp1	/* Shift (tmp1 & 63).  */
+#endif
+	orr	data1, data1, tmp2
+	orr	data2a, data2, tmp2
+	csinv	data1, data1, xzr, le
+	csel	data2, data2, data2a, le
+	b	.Lrealigned
+	.size	strnlen, . - .Lstart	/* Include pre-padding in size.  */
+
+#endif