Relocate AArch64 from ports to libc.

This patch moves the AArch64 port to the main sysdeps hierarchy.  The
move is essentially:

  git mv ports/sysdeps/aarch64 sysdeps/aarch64
  git mv ports/sysdeps/unix/sysv/linux/aarch64 sysdeps/unix/sysv/linux/aarch64

The README is updated and I've updated ChangeLog.aarch64 along the
lines of the ARM move.  The AArch64 build has been tested to confirm
that there were no changes in objdump -dr output or the shared
objects.

1 files changed, 106 insertions, 0 deletions

diff --git a/sysdeps/aarch64/__longjmp.S b/sysdeps/aarch64/__longjmp.S
new file mode 100644
index 0000000000..2d38bbf6a5
--- /dev/null
+++ b/sysdeps/aarch64/__longjmp.S
@@ -0,0 +1,106 @@
+/* Copyright (C) 1997-2014 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/>.  */
+
+#include <sysdep.h>
+#include <jmpbuf-offsets.h>
+
+/* __longjmp(jmpbuf, val) */
+
+ENTRY (__longjmp)
+	cfi_def_cfa(x0, 0)
+	cfi_offset(x19, JB_X19<<3)
+	cfi_offset(x20, JB_X20<<3)
+	cfi_offset(x21, JB_X21<<3)
+	cfi_offset(x22, JB_X22<<3)
+	cfi_offset(x23, JB_X23<<3)
+	cfi_offset(x24, JB_X24<<3)
+	cfi_offset(x25, JB_X25<<3)
+	cfi_offset(x26, JB_X26<<3)
+	cfi_offset(x27, JB_X27<<3)
+	cfi_offset(x28, JB_X28<<3)
+	cfi_offset(x29, JB_X29<<3)
+	cfi_offset(x30, JB_LR<<3)
+
+	cfi_offset( d8, JB_D8<<3)
+	cfi_offset( d9, JB_D9<<3)
+	cfi_offset(d10, JB_D10<<3)
+	cfi_offset(d11, JB_D11<<3)
+	cfi_offset(d12, JB_D12<<3)
+	cfi_offset(d13, JB_D13<<3)
+	cfi_offset(d14, JB_D14<<3)
+	cfi_offset(d15, JB_D15<<3)
+
+	ldp	x19, x20, [x0, #JB_X19<<3]
+	ldp	x21, x22, [x0, #JB_X21<<3]
+	ldp	x23, x24, [x0, #JB_X23<<3]
+	ldp	x25, x26, [x0, #JB_X25<<3]
+	ldp	x27, x28, [x0, #JB_X27<<3]
+#ifdef PTR_DEMANGLE
+	ldp	x29,  x4, [x0, #JB_X29<<3]
+	PTR_DEMANGLE (x30, x4, x3, x2)
+#else
+	ldp	x29, x30, [x0, #JB_X29<<3]
+#endif
+	ldp	 d8,  d9, [x0, #JB_D8<<3]
+	ldp	d10, d11, [x0, #JB_D10<<3]
+	ldp	d12, d13, [x0, #JB_D12<<3]
+	ldp	d14, d15, [x0, #JB_D14<<3]
+
+        /* Originally this was implemented with a series of
+	   .cfi_restore() directives.
+
+           The theory was that cfi_restore should revert to previous
+           frame value is the same as the current value.  In practice
+           this doesn't work, even after cfi_restore() gdb continues
+           to try to recover a previous frame value offset from x0,
+           which gets stuffed after a few more instructions.  The
+           cfi_same_value() mechanism appears to work fine.  */
+
+	cfi_same_value(x19)
+	cfi_same_value(x20)
+	cfi_same_value(x21)
+	cfi_same_value(x22)
+	cfi_same_value(x23)
+	cfi_same_value(x24)
+	cfi_same_value(x25)
+	cfi_same_value(x26)
+	cfi_same_value(x27)
+	cfi_same_value(x28)
+	cfi_same_value(x29)
+	cfi_same_value(x30)
+	cfi_same_value(d8)
+	cfi_same_value(d9)
+	cfi_same_value(d10)
+	cfi_same_value(d11)
+	cfi_same_value(d12)
+	cfi_same_value(d13)
+	cfi_same_value(d14)
+	cfi_same_value(d15)
+#ifdef PTR_DEMANGLE
+	ldr	x4, [x0, #JB_SP<<3]
+	PTR_DEMANGLE (x5, x4, x3, x2)
+#else
+	ldr	x5, [x0, #JB_SP<<3]
+#endif
+	mov	sp, x5
+	cmp	x1, #0
+	mov	x0, #1
+	csel	x0, x1, x0, ne
+	/* Use br instead of ret because ret is guaranteed to mispredict */
+	br	x30
+END (__longjmp)