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authorJoseph Myers <joseph@codesourcery.com>2014-02-08 01:49:39 +0000
committerJoseph Myers <joseph@codesourcery.com>2014-02-08 01:49:39 +0000
commitc6bfe5c4d756913297db03f55e42016d1c48918c (patch)
tree898d2910ef903f46b596ad54e519ed4495357766 /sysdeps/arm/armv6t2/strlen.S
parent852fa2dd3aa1a687780e27300df9eb0bdc433863 (diff)
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Move arm from ports to libc.
I've moved the ARM port from ports to the main sysdeps hierarchy.
Beyond the README update, the move of the files was simply

git mv ports/sysdeps/arm sysdeps/arm
git mv ports/sysdeps/unix/arm sysdeps/unix/arm
git mv ports/sysdeps/unix/sysv/linux/arm sysdeps/unix/sysv/linux/arm

and in addition to the ChangeLog entries here, I put a note at the top
of ports/ChangeLog.arm similar to that at the top of
ChangeLog.powerpc.  There is deliberately no NEWS change, as I think
it makes the most sense to put in a general note above all ports
having moved if we can achieve that for 2.20.

Tested that disassembly of installed shared libraries for arm is the
same before and after this patch, except for data (not instructions)
in ld.so (there are assertions in sysdeps/arm/dl-machine.h, and the
path by which that file is found, and so by which it appears in the
assertion message, changes as a result of the move).

	* sysdeps/arm: Move directory from ports/sysdeps/arm.
	* sysdeps/unix/arm: Move directory from ports/sysdeps/unix/arm.
	* sysdeps/unix/sysv/linux/arm: Move directory from
	ports/sysdeps/unix/sysv/linux/arm.
	* README: Update listing for arm-*-linux-gnueabi.

ports/ChangeLog.arm:
	* sysdeps/arm: Move directory to ../sysdeps/arm.
	* sysdeps/unix/arm: Move directory to ../sysdeps.arm.
	* sysdeps/unix/sysv/linux/arm: Move directory to
	../sysdeps/unix/sysv/linux/arm.
Diffstat (limited to 'sysdeps/arm/armv6t2/strlen.S')
-rw-r--r--sysdeps/arm/armv6t2/strlen.S169
1 files changed, 169 insertions, 0 deletions
diff --git a/sysdeps/arm/armv6t2/strlen.S b/sysdeps/arm/armv6t2/strlen.S
new file mode 100644
index 0000000000..1706f6c6b8
--- /dev/null
+++ b/sysdeps/arm/armv6t2/strlen.S
@@ -0,0 +1,169 @@
+/* Copyright (C) 2010-2014 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/>.  */
+
+/*
+   Assumes:
+   ARMv6T2, AArch32
+
+ */
+
+#include <arm-features.h>               /* This might #define NO_THUMB.  */
+#include <sysdep.h>
+
+#ifdef __ARMEB__
+#define S2LO		lsl
+#define S2HI		lsr
+#else
+#define S2LO		lsr
+#define S2HI		lsl
+#endif
+
+#ifndef NO_THUMB
+/* This code is best on Thumb.  */
+	.thumb
+#else
+/* Using bne.w explicitly is desirable in Thumb mode because it helps
+   align the following label without a nop.  In ARM mode there is no
+   such difference.  */
+.macro bne.w label
+	bne \label
+.endm
+
+/* This clobbers the condition codes, which the real Thumb cbnz instruction
+   does not do.  But it doesn't matter for any of the uses here.  */
+.macro cbnz reg, label
+	cmp \reg, #0
+	bne \label
+.endm
+#endif
+
+/* Parameters and result.  */
+#define srcin		r0
+#define result		r0
+
+/* Internal variables.  */
+#define src		r1
+#define data1a		r2
+#define data1b		r3
+#define const_m1	r12
+#define const_0		r4
+#define tmp1		r4		/* Overlaps const_0  */
+#define tmp2		r5
+
+	.text
+	.p2align 6
+ENTRY(strlen)
+	sfi_pld	srcin, #0
+	strd	r4, r5, [sp, #-8]!
+	cfi_adjust_cfa_offset (8)
+	cfi_rel_offset (r4, 0)
+	cfi_rel_offset (r5, 4)
+	cfi_remember_state
+	bic	src, srcin, #7
+	mvn	const_m1, #0
+	ands	tmp1, srcin, #7		/* (8 - bytes) to alignment.  */
+	sfi_pld	src, #32
+	bne.w	.Lmisaligned8
+	mov	const_0, #0
+	mov	result, #-8
+.Lloop_aligned:
+	/* Bytes 0-7.  */
+	sfi_breg src, \
+	ldrd	data1a, data1b, [\B]
+	sfi_pld	src, #64
+	add	result, result, #8
+.Lstart_realigned:
+	uadd8	data1a, data1a, const_m1	/* Saturating GE<0:3> set.  */
+	sel	data1a, const_0, const_m1	/* Select based on GE<0:3>.  */
+	uadd8	data1b, data1b, const_m1
+	sel	data1b, data1a, const_m1	/* Only used if d1a == 0.  */
+	cbnz	data1b, .Lnull_found
+
+	/* Bytes 8-15.  */
+	sfi_breg src, \
+	ldrd	data1a, data1b, [\B, #8]
+	uadd8	data1a, data1a, const_m1	/* Saturating GE<0:3> set.  */
+	add	result, result, #8
+	sel	data1a, const_0, const_m1	/* Select based on GE<0:3>.  */
+	uadd8	data1b, data1b, const_m1
+	sel	data1b, data1a, const_m1	/* Only used if d1a == 0.  */
+	cbnz	data1b, .Lnull_found
+
+	/* Bytes 16-23.  */
+	sfi_breg src, \
+	ldrd	data1a, data1b, [\B, #16]
+	uadd8	data1a, data1a, const_m1	/* Saturating GE<0:3> set.  */
+	add	result, result, #8
+	sel	data1a, const_0, const_m1	/* Select based on GE<0:3>.  */
+	uadd8	data1b, data1b, const_m1
+	sel	data1b, data1a, const_m1	/* Only used if d1a == 0.  */
+	cbnz	data1b, .Lnull_found
+
+	/* Bytes 24-31.  */
+	sfi_breg src, \
+	ldrd	data1a, data1b, [\B, #24]
+	add	src, src, #32
+	uadd8	data1a, data1a, const_m1	/* Saturating GE<0:3> set.  */
+	add	result, result, #8
+	sel	data1a, const_0, const_m1	/* Select based on GE<0:3>.  */
+	uadd8	data1b, data1b, const_m1
+	sel	data1b, data1a, const_m1	/* Only used if d1a == 0.  */
+	cmp	data1b, #0
+	beq	.Lloop_aligned
+
+.Lnull_found:
+	cmp	data1a, #0
+	itt	eq
+	addeq	result, result, #4
+	moveq	data1a, data1b
+#ifndef __ARMEB__
+	rev	data1a, data1a
+#endif
+	clz	data1a, data1a
+	ldrd	r4, r5, [sp], #8
+	cfi_adjust_cfa_offset (-8)
+	cfi_restore (r4)
+	cfi_restore (r5)
+	add	result, result, data1a, lsr #3	/* Bits -> Bytes.  */
+	DO_RET(lr)
+
+.Lmisaligned8:
+	cfi_restore_state
+	sfi_breg src, \
+	ldrd	data1a, data1b, [\B]
+	and	tmp2, tmp1, #3
+	rsb	result, tmp1, #0
+	lsl	tmp2, tmp2, #3			/* Bytes -> bits.  */
+	tst	tmp1, #4
+	sfi_pld	src, #64
+	S2HI	tmp2, const_m1, tmp2
+#ifdef NO_THUMB
+	mvn	tmp1, tmp2
+	orr	data1a, data1a, tmp1
+	itt	ne
+	orrne	data1b, data1b, tmp1
+#else
+	orn	data1a, data1a, tmp2
+	itt	ne
+	ornne	data1b, data1b, tmp2
+#endif
+	movne	data1a, const_m1
+	mov	const_0, #0
+	b	.Lstart_realigned
+
+END(strlen)
+libc_hidden_builtin_def (strlen)