1/* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License, Version 1.0 only 6 * (the "License"). You may not use this file except in compliance 7 * with the License. 8 * 9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 10 * or http://www.opensolaris.org/os/licensing. 11 * See the License for the specific language governing permissions 12 * and limitations under the License. 13 * 14 * When distributing Covered Code, include this CDDL HEADER in each 15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 16 * If applicable, add the following below this CDDL HEADER, with the 17 * fields enclosed by brackets "[]" replaced with your own identifying 18 * information: Portions Copyright [yyyy] [name of copyright owner] 19 * 20 * CDDL HEADER END 21 */ 22/* 23 * Copyright (c) 1991,1992 by Sun Microsystems, Inc. 24 */ 25#pragma ident "%Z%%M% %I% %E% SMI" 26 27#include "machdep.h" 28#if defined(lint) 29#include <sys/types.h> 30#include "sgs.h" 31#include "_a.out.h" 32#else 33 34 .file "boot_a.out.s" 35 .seg ".text" 36#endif 37 38/* 39 * We got here because the initial call to a function resolved to a procedure 40 * linkage table entry. That entry did a branch to the first PLT entry, which 41 * in turn did a call to aout_rtbndr (refer aout_plt_init()). 42 * 43 * the code sequence that got us here was: 44 * 45 * PLT entry for foo(): 46 * save %sp, -0x60, %sp ! patched first 47 * call .PLT0 ! patched second 48 * sethi %hi(XXXXXXX), %g0 ! unchanged 49 * 50 * Therefore on entry, %i7 has the address of the call, which will be added 51 * to the offset to the plt entry in %g1 to calculate the plt entry address 52 * we must also subtract 4 for because the address of PLT0 points to the 53 * save instruction before the call 54 * 55 * the plt entry is rewritten: 56 * 57 * PLT entry for foo(): 58 * sethi %hi(entry_pt), %g1 59 * jmpl %g1 + %lo(entry_pt), %g0 60 */ 61 62#if defined(lint) 63 64void 65aout_rtbndr(caddr_t pc) 66{ 67 (void) aout_bndr(pc); 68} 69 70#else 71 .global aout_rtbndr 72 .type aout_rtbndr, #function 73 .align 4 74 75aout_rtbndr: 76 save %sp, -80, %sp 77 call aout_bndr ! returns function address in %o0 78 add %i7, -0x4, %o0 ! %o0 now has address of PLT0 79 mov %o0, %g1 ! save address of routine binded 80 restore ! how many restores needed ? 2 81 jmp %g1 ! jump to it 82 restore 83 nop 84 .size aout_rtbndr, . - aout_rtbndr 85 86#endif 87 88 89/* 90 * After the first call to a plt, aout_bndr() will have determined the true 91 * address of the function being bound. The plt is now rewritten so that 92 * any subsequent calls go directly to the bound function. 93 * 94 * the new plt entry is: 95 * 96 * sethi %hi(function address), %g1 ! patched first 97 * jmpl %g1 + %lo(function address, %g0 ! patched second 98 */ 99 100#if defined(lint) 101 102void 103aout_plt_write(caddr_t pc, unsigned long symval) 104{ 105 /* LINTED */ 106 *(unsigned long *)(pc) = (M_SETHIG1 | (symval >> (32 - 22))); 107 /* LINTED */ 108 *(unsigned long *)(pc + 4) = (M_JMPL | (symval & S_MASK(10))); 109 110} 111 112#else 113 .global aout_plt_write 114 .type aout_plt_write, #function 115 .align 4 116 117aout_plt_write: 118 srl %o1, 10, %o2 ! Get high part of function address 119 sethi %hi(M_SETHIG1), %o3 ! Get sethi instruction 120 or %o3, %o2, %o3 ! Add sethi and function address 121 st %o3, [%o0] ! Store instruction in plt[0] 122 iflush %o0 123 stbar 124 sethi %hi(M_JMPL), %o3 ! Get jmpl instruction 125 and %o1, 0x3ff, %o2 ! Lower part of function address 126 or %o3, %o2, %o3 ! is or'ed into instruction 127 st %o3, [%o0 + 4] ! Store instruction in plt[1] 128 retl 129 iflush %o0 + 4 130 .size aout_plt_write, . - aout_plt_write 131 132#endif 133