/* Thread-local storage handling in the ELF dynamic linker.  ARM version.

   Copyright (C) 2006-2018 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 <arm-features.h>

#include <tls.h>

#include "tlsdesc.h"

	.text

	@ emit debug information with cfi

	@ use arm-specific pseudos for unwinding itself

	CFI_SECTIONS

	.hidden _dl_tlsdesc_return

	.global	_dl_tlsdesc_return

	.type	_dl_tlsdesc_return,#function

	cfi_startproc

	eabi_fnstart

	.align 2

_dl_tlsdesc_return:

	ldr	r0, [r0]

	BX	(lr)

	eabi_fnend

	cfi_endproc

	.size	_dl_tlsdesc_return, .-_dl_tlsdesc_return

	.hidden _dl_tlsdesc_undefweak

	.global	_dl_tlsdesc_undefweak

	.type	_dl_tlsdesc_undefweak,#function

	cfi_startproc

	eabi_fnstart

	.align 2

_dl_tlsdesc_undefweak:

	GET_TLS (r1)

	rsb 	r0, r0, #0

	BX	(lr)

	cfi_endproc

	eabi_fnend

	.size	_dl_tlsdesc_undefweak, .-_dl_tlsdesc_undefweak

#ifdef SHARED

	.hidden _dl_tlsdesc_dynamic

	.global	_dl_tlsdesc_dynamic

	.type	_dl_tlsdesc_dynamic,#function

/*

	The assembly code that follows is a rendition of the following

	C code, hand-optimized a little bit.

ptrdiff_t

_dl_tlsdesc_dynamic(struct tlsdesc *tdp)

{

       struct tlsdesc_dynamic_arg *td = tdp->argument.pointer;

       dtv_t *dtv = (dtv_t *)THREAD_DTV();

       if (__builtin_expect (td->gen_count <= dtv[0].counter

                             && dtv[td->tlsinfo.ti_module].pointer.val

                                != TLS_DTV_UNALLOCATED,

                             1))

               return dtv[td->tlsinfo.ti_module].pointer.val +

                       td->tlsinfo.ti_offset - __builtin_thread_pointer();

       return __tls_get_addr (&td->tlsinfo) - __builtin_thread_pointer();

}

*/

	cfi_startproc

	eabi_fnstart

	.align 2

_dl_tlsdesc_dynamic:

	/* Our calling convention is to clobber r0, r1 and the processor

	   flags.  All others that are modified must be saved */

	eabi_save ({r2,r3,r4,lr})

	push	{r2,r3,r4,lr}

	cfi_adjust_cfa_offset (16)

	cfi_rel_offset (r2,0)

	cfi_rel_offset (r3,4)

	cfi_rel_offset (r4,8)

	cfi_rel_offset (lr,12)

	ldr	r1, [r0] /* td */

	GET_TLS (lr)

	mov	r4, r0 /* r4 = tp */

	ldr	r0, [r0]

	ldr	r2, [r1, #8] /* gen_count */

	ldr	r3, [r0]

	cmp	r2, r3

	bhi	1f

	ldr	r3, [r1]

#ifndef ARM_NO_INDEX_REGISTER

	ldr	r2, [r0, r3, lsl #3]

#else

	add	lr, r0, r3, lsl #3

	ldr	r2, [lr]

#endif

	cmn	r2, #1

	ittt	ne

	ldrne	r3, [r1, #4]

	addne	r3, r2, r3

	rsbne	r0, r4, r3

	bne	2f

1:	mov	r0, r1

	bl	__tls_get_addr

	rsb	r0, r4, r0

2:

#if ((defined (__ARM_ARCH_4T__) && defined (__THUMB_INTERWORK__)) \

     || defined (ARM_ALWAYS_BX))

	pop	{r2,r3,r4, lr}

	cfi_adjust_cfa_offset (-16)

	cfi_restore (lr)

	cfi_restore (r4)

	cfi_restore (r3)

	cfi_restore (r2)

	bx	lr

#else

	pop	{r2,r3,r4, pc}

#endif

	eabi_fnend

	cfi_endproc

	.size	_dl_tlsdesc_dynamic, .-_dl_tlsdesc_dynamic

#endif /* SHARED */