/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (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 2004 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#include        <stdio.h>
#include        <proc_service.h>
#include        <link.h>
#include        <rtld_db.h>
#include        <_rtld_db.h>
#include        <msg.h>


/*
 * A un-initialized PLT look like so:
 *
 * .PLT
 *      sethi   (.-.PLT0), %g1
 *      ba,a    .PLT0
 *      nop
 *
 * To test to see if this is an uninitialized PLT we check
 * the second instruction and confirm that it's a branch.
 */
/* ARGSUSED 2 */
rd_err_e
plt32_resolution(rd_agent_t *rap, psaddr_t pc, lwpid_t lwpid,
        psaddr_t pltbase, rd_plt_info_t *rpi)
{
        unsigned int    instr[4];
        rd_err_e        rerr;
        psaddr_t        destaddr = 0;
        psaddr_t        pltoff, pltaddr;
        int             pltbound = 0;

        pltoff = pc - pltbase;
        pltaddr = pltbase +
                ((pltoff / M32_PLT_ENTSIZE) * M32_PLT_ENTSIZE);

        if (ps_pread(rap->rd_psp, pltaddr, (char *)instr,
            M32_PLT_ENTSIZE) != PS_OK) {
                LOG(ps_plog(MSG_ORIG(MSG_DB_READFAIL_2), EC_ADDR(pltaddr)));
                return (RD_ERR);
        }

        if (rtld_db_version >= RD_VERSION3) {
                rpi->pi_flags = 0;
                rpi->pi_baddr = 0;
        }

        if ((instr[0] != M_NOP) &&
            ((instr[1] & (~(S_MASK(22)))) == M_BA_A)) {
                /*
                 * Unbound PLT
                 */
                if ((rerr = rd_binder_exit_addr(rap, MSG_ORIG(MSG_SYM_RTBIND),
                    &(rpi->pi_target))) != RD_OK) {
                        return (rerr);
                }
                rpi->pi_skip_method = RD_RESOLVE_TARGET_STEP;
                rpi->pi_nstep = 1;
        } else if ((instr[2] & (~(S_MASK(13)))) == M_JMPL) {
                /*
                 * Resolved 32-bit PLT entry format (full-32):
                 *
                 * .PLT:
                 * 0    sethi   (.-PLT0), %g1
                 * 1    sethi   %hi(dest), %g1
                 * 2    jmpl    %g1 + lo(dest), %g0
                 * 3    nop
                 */
                rpi->pi_skip_method = RD_RESOLVE_STEP;
                rpi->pi_nstep = 4;
                rpi->pi_target = 0;
                if (rtld_db_version >= RD_VERSION3) {
                        uint_t          hi_bits;
                        uint_t          lo_bits;
                        hi_bits = instr[1] & S_MASK(22); /* 31..10 */
                        lo_bits = instr[2] & S_MASK(10); /* 09..00 */
                        destaddr = (hi_bits << 10) | lo_bits;
                        pltbound++;
                }
        } else  if ((instr[0] == M_NOP) &&
            ((instr[1] & (~(S_MASK(22)))) == M_BA_A)) {
                /*
                 * Resolved 32-bit PLT entry format (b+-8mb):
                 * .PLT
                 * 0    nop
                 * 1    ba,a    <dest>
                 * 2    nop
                 * 3    nop
                 */
                rpi->pi_skip_method = RD_RESOLVE_STEP;
                rpi->pi_nstep = 2;
                rpi->pi_target = 0;
                if (rtld_db_version >= RD_VERSION3) {
                        uint_t  d22;
                        d22 = instr[1] & S_MASK(22);
                        destaddr = ((int)pltaddr + 4) +
                                (((int)d22 << 10) >> 8);
                        pltbound++;
                }
        } else if ((instr[0] == M_NOP) &&
            ((instr[1] & (~(S_MASK(19)))) == M_BA_A_PT)) {
                /*
                 * Resolved 32-bit PLT entry format (b+-2mb):
                 * .PLT
                 * 0    nop
                 * 1    ba,a,pt %icc, <dest>
                 * 2    nop
                 * 3    nop
                 */
                rpi->pi_skip_method = RD_RESOLVE_STEP;
                rpi->pi_nstep = 2;
                rpi->pi_target = 0;
                if (rtld_db_version >= RD_VERSION3) {
                        uint_t  d19;
                        d19 = instr[1] & S_MASK(22);
                        destaddr = ((int)pltaddr + 4) +
                                (((int)d19 << 13) >> 11);
                        pltbound++;
                }
        } else
                rpi->pi_skip_method = RD_RESOLVE_NONE;

        if ((rtld_db_version >= RD_VERSION3) && pltbound) {
                rpi->pi_flags |= RD_FLG_PI_PLTBOUND;
                rpi->pi_baddr = destaddr;
        }
        return (RD_OK);
}