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-rw-r--r--sysdeps/unix/sysv/linux/mips/clone.S177
1 files changed, 177 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/mips/clone.S b/sysdeps/unix/sysv/linux/mips/clone.S
new file mode 100644
index 0000000000..d3fd80f993
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/mips/clone.S
@@ -0,0 +1,177 @@
+/* Copyright (C) 1996-2014 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Ralf Baechle <ralf@linux-mips.org>, 1996.
+
+   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/>.  */
+
+/* clone() is even more special than fork() as it mucks with stacks
+   and invokes a function in the right context after its all over.  */
+
+#include <sys/asm.h>
+#include <sysdep.h>
+#define _ERRNO_H	1
+#include <bits/errno.h>
+#ifdef RESET_PID
+#include <tls.h>
+#endif
+
+#define CLONE_VM      0x00000100
+#define CLONE_THREAD  0x00010000
+
+/* int clone(int (*fn)(void *arg), void *child_stack, int flags, void *arg,
+	     void *parent_tidptr, void *tls, void *child_tidptr) */
+
+	.text
+	.set		nomips16
+#if _MIPS_SIM == _ABIO32
+# define EXTRA_LOCALS 1
+#else
+# define EXTRA_LOCALS 0
+#endif
+LOCALSZ= 4
+FRAMESZ= (((NARGSAVE+LOCALSZ)*SZREG)+ALSZ)&ALMASK
+GPOFF= FRAMESZ-(1*SZREG)
+NESTED(__clone,4*SZREG,sp)
+#ifdef __PIC__
+	SETUP_GP
+#endif
+	PTR_SUBU sp, FRAMESZ
+	cfi_adjust_cfa_offset (FRAMESZ)
+	SETUP_GP64_STACK (GPOFF, __clone)
+#ifdef __PIC__
+	SAVE_GP (GPOFF)
+#endif
+#ifdef PROF
+	.set		noat
+	move		$1,ra
+	jal		_mcount
+	.set		at
+#endif
+
+
+	/* Sanity check arguments.  */
+	li		v0,EINVAL
+	beqz		a0,L(error)	/* No NULL function pointers.  */
+	beqz		a1,L(error)	/* No NULL stack pointers.  */
+
+	PTR_SUBU	a1,32		/* Reserve argument save space.  */
+	PTR_S		a0,0(a1)	/* Save function pointer.  */
+	PTR_S		a3,PTRSIZE(a1)	/* Save argument pointer.  */
+#ifdef RESET_PID
+	LONG_S		a2,(PTRSIZE*2)(a1)	/* Save clone flags.  */
+#endif
+
+	move		a0,a2
+
+	/* Shuffle in the last three arguments - arguments 5, 6, and 7 to
+	   this function, but arguments 3, 4, and 5 to the syscall.  */
+#if _MIPS_SIM == _ABIO32
+	PTR_L		a2,(FRAMESZ+PTRSIZE+PTRSIZE+16)(sp)
+	PTR_S		a2,16(sp)
+	PTR_L		a2,(FRAMESZ+16)(sp)
+	PTR_L		a3,(FRAMESZ+PTRSIZE+16)(sp)
+#else
+	move		a2,a4
+	move		a3,a5
+	move		a4,a6
+#endif
+
+	/* Do the system call */
+	li		v0,__NR_clone
+	cfi_endproc
+	syscall
+
+	bnez		a3,L(error)
+	beqz		v0,L(thread_start)
+
+	/* Successful return from the parent */
+	cfi_startproc
+	cfi_adjust_cfa_offset (FRAMESZ)
+	SETUP_GP64_STACK_CFI (GPOFF)
+	cfi_remember_state
+	RESTORE_GP64_STACK
+	PTR_ADDU	sp, FRAMESZ
+	cfi_adjust_cfa_offset (-FRAMESZ)
+	ret
+
+	/* Something bad happened -- no child created */
+L(error):
+	cfi_restore_state
+#ifdef __PIC__
+	PTR_LA		t9,__syscall_error
+	RESTORE_GP64_STACK
+	PTR_ADDU	sp, FRAMESZ
+	cfi_adjust_cfa_offset (-FRAMESZ)
+	jr		t9
+#else
+	RESTORE_GP64_STACK
+	PTR_ADDU	sp, FRAMESZ
+	cfi_adjust_cfa_offset (-FRAMESZ)
+	j		__syscall_error
+#endif
+	END(__clone)
+
+/* Load up the arguments to the function.  Put this block of code in
+   its own function so that we can terminate the stack trace with our
+   debug info.  */
+
+ENTRY(__thread_start)
+L(thread_start):
+	cfi_undefined ($31)
+	/* cp is already loaded.  */
+	SAVE_GP (GPOFF)
+	/* The stackframe has been created on entry of clone().  */
+
+#ifdef RESET_PID
+	/* Check and see if we need to reset the PID.  */
+	LONG_L		a0,(PTRSIZE*2)(sp)
+	and		a1,a0,CLONE_THREAD
+	beqz		a1,L(restore_pid)
+L(donepid):
+#endif
+
+	/* Restore the arg for user's function.  */
+	PTR_L		t9,0(sp)	/* Function pointer.  */
+	PTR_L		a0,PTRSIZE(sp)	/* Argument pointer.  */
+
+	/* Call the user's function.  */
+	jal		t9
+
+	/* Call _exit rather than doing it inline for breakpoint purposes.  */
+	move		a0,v0
+#ifdef __PIC__
+	PTR_LA		t9,_exit
+	jalr		t9
+#else
+	jal		_exit
+#endif
+
+#ifdef RESET_PID
+L(restore_pid):
+	and		a1,a0,CLONE_VM
+	li		v0,-1
+	bnez		a1,L(gotpid)
+	li		v0,__NR_getpid
+	syscall
+L(gotpid):
+	READ_THREAD_POINTER(v1)
+	INT_S		v0,PID_OFFSET(v1)
+	INT_S		v0,TID_OFFSET(v1)
+	b		L(donepid)
+#endif
+
+	END(__thread_start)
+
+weak_alias (__clone, clone)