/* Stack-aligning implementation of __tls_get_addr.  x86-64 version.

   Copyright (C) 2017-2018 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/>.  */

#ifdef SHARED

# include <sysdep.h>

# include "tlsdesc.h"

# include "rtld-offsets.h"

/* See __tls_get_addr and __tls_get_addr_slow in dl-tls.c.  This function

   call __tls_get_addr_slow on both slow paths.  It realigns the stack

   before the call to work around GCC PR58066.  */

ENTRY (__tls_get_addr)

	mov 	%fs:DTV_OFFSET, %RDX_LP

	mov	GL_TLS_GENERATION_OFFSET+_rtld_local(%rip), %RAX_LP

	/* GL(dl_tls_generation) == dtv[0].counter */

	cmp	%RAX_LP, (%rdx)

	jne	1f

	mov	TI_MODULE_OFFSET(%rdi), %RAX_LP

	/* dtv[ti->ti_module] */

# ifdef __LP64__

	salq	$4, %rax

	movq	(%rdx,%rax), %rax

# else

	movl	(%rdx,%rax, 8), %eax

# endif

	cmp	$-1, %RAX_LP

	je	1f

	add	TI_OFFSET_OFFSET(%rdi), %RAX_LP

	ret

1:

	/* On the slow path, align the stack.  */

	pushq	%rbp

	cfi_def_cfa_offset (16)

	cfi_offset (%rbp, -16)

	mov	%RSP_LP, %RBP_LP

	cfi_def_cfa_register (%rbp)

	and	$-16, %RSP_LP

	call	__tls_get_addr_slow

	mov	%RBP_LP, %RSP_LP

	popq	%rbp

	cfi_def_cfa (%rsp, 8)

	ret

END (__tls_get_addr)

#endif /* SHARED */