/* $NetBSD: rtld_start.S,v 1.12 2013/12/03 00:19:56 matt Exp $ */ /*- * Copyright (c) 1998, 2002 The NetBSD Foundation, Inc. * All rights reserved. * * This code is derived from software contributed to The NetBSD Foundation * by Matt Thomas and by Charles M. Hannum. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. */ #include RCSID("$NetBSD: rtld_start.S,v 1.12 2013/12/03 00:19:56 matt Exp $") ENTRY_NP(_rtld_start) sub sp, sp, #8 /* make room for obj_main & exit proc */ movs r4, r0 /* save ps_strings */ ldr r6, .Lgot ldr r5, .Ldynamic add r6, r6, pc /* r6 = &GOT[0]; pc = &LPIC1; */ adds r0, r6, r5 /* arg0 = &_DYNAMIC */ .LPIC1: ldr r5, [r6] /* GOT[0] = &_DYNAMIC */ subs r5, r0, r5 /* relocbase = GOT[0] - &_DYNAMIC */ movs r1, r5 /* arg1 = relocabase */ bl _rtld_relocate_nonplt_self movs r1, r5 /* relocbase */ mov r0, sp /* sp */ bl _rtld /* call the shared loader */ movs r3, r0 /* save entry point */ #ifdef __thumb__ ldr r2, [sp, #0] /* pop r2 = cleanup */ ldr r1, [sp, #4] /* pop r1 = obj_main */ add sp, sp, #8 #else ldr r2, [sp], #4 /* pop r2 = cleanup */ ldr r1, [sp], #4 /* pop r1 = obj_main */ #endif movs r0, r4 /* restore ps_strings */ RETr(r3) .align 0 .Lgot: .word _GLOBAL_OFFSET_TABLE_ - .LPIC1 .Ldynamic: .word _DYNAMIC(GOTOFF) END(_rtld_start) /* * stack[0] = RA * ip = &GOT[n+3] * lr = &GOT[2] */ ARM_ENTRY_NP(_rtld_bind_start) stmdb sp!,{r0-r4,sl,fp} /* 8 byte aligned (lr already saved) */ sub r1, ip, lr /* r1 = 4 * (n + 1) */ sub r1, r1, #4 /* r1 = 4 * n */ add r1, r1, r1 /* r1 = 8 * n */ ldr r0, [lr, #-4] /* get obj ptr from GOT[1] */ mov r4, ip /* save GOT location */ bl _rtld_bind /* Call the binder */ str r0, [r4] /* save address in GOT */ mov ip, r0 /* save new address */ ldmia sp!,{r0-r4,sl,fp,lr} /* restore the stack */ RETr(ip) /* jump to the new address */ END(_rtld_bind_start)