Move mips from ports to libc.

I've moved the MIPS port from ports to the main sysdeps hierarchy.
Beyond the README update, the move of the files was simply

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

and in addition to the ChangeLog entries here, I put a note at the top
of ports/ChangeLog.mips similar to those in other files.

Tested that disassembly of installed shared libraries for mips is the
same before and after this patch (except for ld.so where paths in
assertions are involved, as for arm).

	* sysdeps/mips: Move directory from ports/sysdeps/mips.
	* sysdeps/unix/mips: Move directory from ports/sysdeps/unix/mips.
	* sysdeps/unix/sysv/linux/mips: Move directory from
	ports/sysdeps/unix/sysv/linux/mips.
	* README: Update listing for mips-*-linux-gnu and
	mips64-*-linux-gnu.

	* sysdeps/mips: Move directory to ../sysdeps/mips.
	* sysdeps/unix/mips: Move directory to ../sysdeps/unix/mips.
	* sysdeps/unix/sysv/linux/mips: Move directory to
	../sysdeps/unix/sysv/linux/mips.

1 files changed, 181 insertions, 0 deletions

diff --git a/sysdeps/mips/start.S b/sysdeps/mips/start.S
new file mode 100644
index 0000000000..a454941e55
--- /dev/null
+++ b/sysdeps/mips/start.S
@@ -0,0 +1,181 @@
+/* Startup code compliant to the ELF Mips ABI.
+   Copyright (C) 1995-2014 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.
+
+   In addition to the permissions in the GNU Lesser General Public
+   License, the Free Software Foundation gives you unlimited
+   permission to link the compiled version of this file with other
+   programs, and to distribute those programs without any restriction
+   coming from the use of this file. (The GNU Lesser General Public
+   License restrictions do apply in other respects; for example, they
+   cover modification of the file, and distribution when not linked
+   into another program.)
+
+   Note that people who make modified versions of this file are not
+   obligated to grant this special exception for their modified
+   versions; it is their choice whether to do so. The GNU Lesser
+   General Public License gives permission to release a modified
+   version without this exception; this exception also makes it
+   possible to release a modified version which carries forward this
+   exception.
+
+   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/>.  */
+
+#define __ASSEMBLY__ 1
+#include <entry.h>
+#include <sgidefs.h>
+#include <sys/asm.h>
+
+#ifndef ENTRY_POINT
+#error ENTRY_POINT needs to be defined for start.S on MIPS/ELF.
+#endif
+
+/* This is the canonical entry point, usually the first thing in the text
+   segment.  The SVR4/Mips ABI (pages 3-31, 3-32) says that when the entry
+   point runs, most registers' values are unspecified, except for:
+
+   v0 ($2)	Contains a function pointer to be registered with `atexit'.
+		This is how the dynamic linker arranges to have DT_FINI
+		functions called for shared libraries that have been loaded
+		before this code runs.
+
+   sp ($29)	The stack contains the arguments and environment:
+		0(%esp)			argc
+		4(%esp)			argv[0]
+		...
+		(4*argc)(%esp)		NULL
+		(4*(argc+1))(%esp)	envp[0]
+		...
+					NULL
+   ra ($31)	The return address register is set to zero so that programs
+		that search backword through stack frames recognize the last
+		stack frame.
+*/
+
+
+/* We need to call:
+   __libc_start_main (int (*main) (int, char **, char **), int argc,
+		      char **argv, void (*init) (void), void (*fini) (void),
+		      void (*rtld_fini) (void), void *stack_end)
+*/
+
+	.text
+	.globl ENTRY_POINT
+	.type ENTRY_POINT,@function
+#ifndef __mips16
+ENTRY_POINT:
+# ifdef __PIC__
+	SETUP_GPX($0)
+	SETUP_GPX64($25,$0)
+# else
+	PTR_LA $28, _gp		/* Setup GP correctly if we're non-PIC.  */
+	move $31, $0
+# endif
+
+	PTR_LA $4, main		/* main */
+	PTR_L $5, 0($29)		/* argc */
+	PTR_ADDIU $6, $29, PTRSIZE	/* argv  */
+
+	/* Allocate space on the stack for seven arguments (o32 only)
+	   and make sure the stack is aligned to double words (8 bytes)
+	   on o32 and quad words (16 bytes) on n32 and n64.  */
+
+	and $29, -2 * SZREG
+# if _MIPS_SIM == _ABIO32
+	PTR_SUBIU $29, 32
+# endif
+	PTR_LA $7, __libc_csu_init		/* init */
+	PTR_LA $8, __libc_csu_fini
+# if _MIPS_SIM == _ABIO32
+	PTR_S $8, 16($29)		/* fini */
+	PTR_S $2, 20($29)		/* rtld_fini */
+	PTR_S $29, 24($29)		/* stack_end */
+# else
+	move $9, $2		/* rtld_fini */
+	move $10, $29		/* stack_end */
+# endif
+	jal __libc_start_main
+hlt:	b hlt			/* Crash if somehow it does return.  */
+
+#elif _MIPS_SIM == _ABIO32 /* __mips16 */
+	/* MIPS16 entry point.  */
+	.set	mips16
+ENTRY_POINT:
+# ifdef __PIC__
+	li	$3, %hi(_gp_disp)
+	addiu	$4, $pc, %lo(_gp_disp)
+	sll	$3, 16
+	addu	$3, $4
+	move	$gp, $3
+# else
+	li	$3, %hi(_gp)
+	sll	$3, 16
+	addiu	$3, %lo(_gp)
+	move	$gp, $3
+# endif
+	/* Tie end of stack frames.  */
+	li	$4, 0
+	move	$31, $4
+	/* Create new SP value in $7, including alignment.  */
+	li	$4, 2 * SZREG
+	neg	$4, $4
+	move	$7, $sp
+	and	$7, $4
+	addiu	$7, -32
+	/* Load arguments with original SP.  */
+	lw	$5, 0($sp)
+	addiu	$6, $sp, PTRSIZE
+	/* Update SP.  */
+	move	$sp, $7
+	/* Lay out last arguments, and call __libc_start_main().  */
+# ifdef __PIC__
+	sw	$7, 24($sp)			/* stack_end */
+	lw	$4, %got(__libc_csu_fini)($3)
+	lw	$7, %got(__libc_csu_init)($3)	/* init */
+	sw	$4, 16($sp)			/* fini */
+	lw	$4, %got(main)($3)		/* main */
+	lw	$3, %call16(__libc_start_main)($3)
+	sw	$2, 20($sp)			/* rtld_fini */
+	move	$25, $3
+	jalr	$3
+# else
+	lw	$4, 1f
+	sw	$7, 24($sp)			/* stack_end */
+	lw	$7, 2f				/* init */
+	sw	$4, 16($sp)			/* fini */
+	lw	$4, 3f				/* main */
+	sw	$2, 20($sp)			/* rtld_fini */
+	jal	__libc_start_main
+# endif
+hlt:	b	hlt		/* Crash if somehow it does return.  */
+# ifndef __PIC__
+	.align	2
+1:	.word	__libc_csu_fini
+2:	.word	__libc_csu_init
+3:	.word	main
+# endif
+
+#else /* __mips16 && _MIPS_SIM != _ABIO32 */
+# error "MIPS16 support for N32/N64 not implemented"
+
+#endif /* __mips16 */
+
+/* Define a symbol for the first piece of initialized data.  */
+	.data
+	.globl __data_start
+__data_start:
+	.long 0
+	.weak data_start
+	data_start = __data_start