/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

        .file   "tls_get_addr.s"

#include "SYS.h"
#include <../assym.h>

/*
 * To make thread-local storage accesses as fast as possible, we
 * hand-craft the __tls_get_addr() function below, from this C code:
 * void *
 * __tls_get_addr(TLS_index *tls_index)
 * {
 *      ulwp_t *self = curthread;
 *      tls_t *tlsent = self->ul_tlsent;
 *      ulong_t moduleid;
 *      caddr_t base;
 *
 *      if ((moduleid = tls_index->ti_moduleid) < self->ul_ntlsent &&
 *          (base = tlsent[moduleid].tls_data) != NULL)
 *              return (base + tls_index->ti_tlsoffset);
 *
 *      return (slow_tls_get_addr(tls_index));
 * }
 */

/*
 * We assume that the tls_t structure contains two pointer-sized elements.
 * Cause a build failure if this becomes not true.
 */
#if     SIZEOF_TLS_T == 8 && !defined(__sparcv9)
#define SHIFT   3
#elif   SIZEOF_TLS_T == 16 && defined(__sparcv9)
#define SHIFT   4
#else
#error  "Assumption violated: SIZEOF_TLS_T is not 2 * sizeof (uintptr_t)"
#endif

#if     defined(__sparcv9)
#define PN      ,pn %xcc,
#else
#define PN
#endif

        ENTRY(__tls_get_addr)
        ldn     [%o0 + TI_MODULEID], %o1
        ldn     [%g7 + UL_TLSENT], %o2
        ldn     [%g7 + UL_NTLSENT], %o3
        cmp     %o1, %o3
        bgeu PN 1f
        slln    %o1, SHIFT, %o1
#if TLS_DATA != 0
        add     %o1, TLS_DATA, %o1
#endif
        ldn     [%o1 + %o2], %o2
        cmp     %o2, 0
        be PN   1f
        ldn     [%o0 + TI_TLSOFFSET], %o1
        retl
        add     %o1, %o2, %o0
1:
        mov     %o7, %g1
        call    slow_tls_get_addr
        mov     %g1, %o7
        SET_SIZE(__tls_get_addr)