/* * 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 (c) 1991,1992 by Sun Microsystems, Inc. */ #pragma ident "%Z%%M% %I% %E% SMI" #include "machdep.h" #if defined(lint) #include #include "sgs.h" #include "_a.out.h" #else .file "boot_a.out.s" .seg ".text" #endif /* * We got here because the initial call to a function resolved to a procedure * linkage table entry. That entry did a branch to the first PLT entry, which * in turn did a call to aout_rtbndr (refer aout_plt_init()). * * the code sequence that got us here was: * * PLT entry for foo(): * save %sp, -0x60, %sp ! patched first * call .PLT0 ! patched second * sethi %hi(XXXXXXX), %g0 ! unchanged * * Therefore on entry, %i7 has the address of the call, which will be added * to the offset to the plt entry in %g1 to calculate the plt entry address * we must also subtract 4 for because the address of PLT0 points to the * save instruction before the call * * the plt entry is rewritten: * * PLT entry for foo(): * sethi %hi(entry_pt), %g1 * jmpl %g1 + %lo(entry_pt), %g0 */ #if defined(lint) void aout_rtbndr(caddr_t pc) { (void) aout_bndr(pc); } #else .global aout_rtbndr .type aout_rtbndr, #function .align 4 aout_rtbndr: save %sp, -80, %sp call aout_bndr ! returns function address in %o0 add %i7, -0x4, %o0 ! %o0 now has address of PLT0 mov %o0, %g1 ! save address of routine binded restore ! how many restores needed ? 2 jmp %g1 ! jump to it restore nop .size aout_rtbndr, . - aout_rtbndr #endif /* * After the first call to a plt, aout_bndr() will have determined the true * address of the function being bound. The plt is now rewritten so that * any subsequent calls go directly to the bound function. * * the new plt entry is: * * sethi %hi(function address), %g1 ! patched first * jmpl %g1 + %lo(function address, %g0 ! patched second */ #if defined(lint) void aout_plt_write(caddr_t pc, unsigned long symval) { /* LINTED */ *(unsigned long *)(pc) = (M_SETHIG1 | (symval >> (32 - 22))); /* LINTED */ *(unsigned long *)(pc + 4) = (M_JMPL | (symval & S_MASK(10))); } #else .global aout_plt_write .type aout_plt_write, #function .align 4 aout_plt_write: srl %o1, 10, %o2 ! Get high part of function address sethi %hi(M_SETHIG1), %o3 ! Get sethi instruction or %o3, %o2, %o3 ! Add sethi and function address st %o3, [%o0] ! Store instruction in plt[0] iflush %o0 stbar sethi %hi(M_JMPL), %o3 ! Get jmpl instruction and %o1, 0x3ff, %o2 ! Lower part of function address or %o3, %o2, %o3 ! is or'ed into instruction st %o3, [%o0 + 4] ! Store instruction in plt[1] retl iflush %o0 + 4 .size aout_plt_write, . - aout_plt_write #endif