From a334319f6530564d22e775935d9c91663623a1b4 Mon Sep 17 00:00:00 2001
From: Ulrich Drepper <drepper@redhat.com>
Date: Wed, 22 Dec 2004 20:10:10 +0000
Subject: (CFLAGS-tst-align.c): Add -mpreferred-stack-boundary=4.

---
 sysdeps/unix/sysv/linux/arm/mmap.S | 92 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 92 insertions(+)
 create mode 100644 sysdeps/unix/sysv/linux/arm/mmap.S

(limited to 'sysdeps/unix/sysv/linux/arm/mmap.S')

diff --git a/sysdeps/unix/sysv/linux/arm/mmap.S b/sysdeps/unix/sysv/linux/arm/mmap.S
new file mode 100644
index 0000000000..cf6f253378
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/arm/mmap.S
@@ -0,0 +1,92 @@
+/* Copyright (C) 1998, 2000, 2003 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, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <sysdep.h>
+#include <kernel-features.h>
+
+#define	EINVAL		22
+
+	.text
+
+ENTRY (__mmap)
+# ifdef __ASSUME_MMAP2_SYSCALL
+	/* This code is actually a couple of cycles slower than the
+	   sys_mmap version below, so it might seem like a loss.  But the
+	   code path inside the kernel is sufficiently much shorter to
+	   make it a net gain to use mmap2 when it's known to be
+	   available.  */
+
+	/* shuffle args */
+	str	r5, [sp, #-4]!
+	ldr	r5, [sp, #8]
+	str	r4, [sp, #-4]!
+	ldr	r4, [sp, #8]
+
+	/* convert offset to pages */
+	movs	ip, r5, lsl #20
+	bne	.Linval
+	mov	r5, r5, lsr #12
+	
+	/* do the syscall */
+	swi	SYS_ify (mmap2)
+
+	/* restore registers */
+2:
+	ldr	r4, [sp], #4
+	ldr	r5, [sp], #4
+
+	cmn	r0, $4096
+	RETINSTR(cc, lr)
+	b	PLTJMP(syscall_error)
+
+.Linval:
+	mov	r0, #-EINVAL
+	b	2b
+# else
+	/* Because we can only get five args through the syscall interface, and
+	   mmap() takes six, we need to build a parameter block and pass its
+	   address instead.  The 386 port does a similar trick.  */
+
+	/* This code previously moved sp into ip and stored the args using
+	   stmdb ip!, {a1-a4}.  It did not modify sp, so the stack never had
+	   to be restored after the syscall completed.  It saved an
+	   instruction and meant no stack cleanup work was required.
+
+	   This will not work in the case of a mmap call being interrupted
+	   by a signal.  If the signal handler uses any stack the arguments
+	   to mmap will be trashed.  The results of a restart of mmap are
+	   then unpredictable. */
+
+	/* store args on the stack */
+	stmdb	sp!, {a1-a4}
+
+	/* do the syscall */
+	mov	a1, sp
+	swi	SYS_ify (mmap)
+
+	/* pop args off the stack. */
+	add	sp, sp, #16
+
+	cmn	r0, $4096
+	RETINSTR(cc, lr)
+	b	PLTJMP(syscall_error);
+#endif
+
+PSEUDO_END (__mmap)
+
+weak_alias (__mmap, mmap)
-- 
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