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 2003 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27#pragma ident "@(#)st_bugs.c 1.5 05/06/08 SMI" 28 29/* 30 * Workarounds for stabs generation bugs in the compiler 31 */ 32 33#include <stdio.h> 34#include <strings.h> 35 36#include "ctf_headers.h" 37#include "ctftools.h" 38#include "hash.h" 39#include "memory.h" 40 41/* 42 * Due to 4432619, the 6.1 compiler will sometimes incorrectly generate pointer 43 * stabs. Given a struct foo, and a corresponding typedef struct foo foo_t. 44 * In some cases, when faced with a pointer to a foo_t, the compiler will 45 * sometimes generate a stab that describes a pointer to a struct foo. 46 * Regardless of correctness, this breaks merges, as it occurs inconsistently 47 * by file. The following two routines know how to recognize and repair foo_t * 48 * and foo_t ** bugs in a specific set of cases. There is no general way to 49 * solve this problem without a fix to the compiler. In general, cases should 50 * only be added to these routines to fix merging problems in genunix. 51 */ 52static void 53fix_ptrptr_to_struct(tdata_t *td) 54{ 55 char *strs[2] = { "as", "fdbuffer" }; 56 char *mems[2] = { "a_objectdir", "fd_shadow" }; 57 char *acts[2] = { "vnode", "page" }; 58 char *tgts[2] = { "vnode_t", "page_t" }; 59 tdesc_t *str; 60 tdesc_t *act, *tgt; 61 tdesc_t *p1, *p2; 62 mlist_t *ml; 63 int i; 64 65 for (i = 0; i < sizeof (strs) / sizeof (strs[0]); i++) { 66 if (!(str = lookupname(strs[i])) || str->t_type != STRUCT) 67 continue; 68 69 for (ml = str->t_members; ml; ml = ml->ml_next) { 70 if (streq(ml->ml_name, mems[i])) 71 break; 72 } 73 if (!ml) 74 continue; 75 76 if (ml->ml_type->t_type != POINTER || ml->ml_type->t_name || 77 ml->ml_type->t_tdesc->t_type != POINTER || 78 ml->ml_type->t_tdesc->t_name) 79 continue; 80 81 act = ml->ml_type->t_tdesc->t_tdesc; 82 if (act->t_type != STRUCT || !streq(act->t_name, acts[i])) 83 continue; 84 85 if (!(tgt = lookupname(tgts[i])) || tgt->t_type != TYPEDEF) 86 continue; 87 88 /* We have an instance of the bug */ 89 p2 = xcalloc(sizeof (*p2)); 90 p2->t_type = POINTER; 91 p2->t_id = td->td_nextid++; 92 p2->t_tdesc = tgt; 93 94 p1 = xcalloc(sizeof (*p1)); 95 p1->t_type = POINTER; 96 p1->t_id = td->td_nextid++; 97 p1->t_tdesc = p2; 98 99 ml->ml_type = p1; 100 101 debug(3, "Fixed %s->%s => ptrptr struct %s bug\n", 102 strs[i], mems[i], acts[i]); 103 } 104} 105 106static void 107fix_ptr_to_struct(tdata_t *td) 108{ 109 char *strs[2] = { "vmem", "id_space" }; 110 char *mems[2] = { NULL, "is_vmem" }; 111 tdesc_t *ptr = NULL; 112 tdesc_t *str, *vmt; 113 mlist_t *ml; 114 int i; 115 116 if ((vmt = lookupname("vmem_t")) == NULL || vmt->t_type != TYPEDEF) 117 return; 118 119 for (i = 0; i < sizeof (strs) / sizeof (strs[0]); i++) { 120 if (!(str = lookupname(strs[i])) || str->t_type != STRUCT) 121 continue; 122 123 for (ml = str->t_members; ml; ml = ml->ml_next) { 124 if (mems[i] && !streq(ml->ml_name, mems[i])) 125 continue; 126 127 if (ml->ml_type->t_type != POINTER || 128 ml->ml_type->t_name || 129 (ml->ml_type->t_tdesc->t_type != STRUCT && 130 ml->ml_type->t_tdesc->t_type != FORWARD) || 131 !streq(ml->ml_type->t_tdesc->t_name, "vmem")) 132 continue; 133 134 debug(3, "Fixed %s->%s => ptr struct vmem bug\n", 135 strs[i], ml->ml_name); 136 137 if (!ptr) { 138 ptr = xcalloc(sizeof (*ptr)); 139 ptr->t_type = POINTER; 140 ptr->t_id = td->td_nextid++; 141 ptr->t_tdesc = vmt; 142 } 143 144 ml->ml_type = ptr; 145 } 146 } 147} 148 149/* 150 * The cpu structure grows, with the addition of a machcpu member, if 151 * _MACHDEP is defined. This means that, for example, the cpu structure 152 * in unix is different from the cpu structure in genunix. As one might 153 * expect, this causes merges to fail. Since everyone indirectly contains 154 * a pointer to a CPU structure, the failed merges can cause massive amounts 155 * of duplication. In the case of unix uniquifying against genunix, upwards 156 * of 50% of the structures were unmerged due to this problem. We fix this 157 * by adding a cpu_m member. If machcpu hasn't been defined in our module, 158 * we make a forward node for it. 159 */ 160static void 161fix_small_cpu_struct(tdata_t *td) 162{ 163 tdesc_t *cput, *cpu; 164 tdesc_t *machcpu; 165 mlist_t *ml, *lml; 166 mlist_t *cpum; 167 int foundcpucyc = 0; 168 size_t lmlsz; 169 170 /* 171 * We're going to take the circuitous route finding the cpu structure, 172 * because we want to make sure that we find the right one. It would 173 * be nice if we could verify the header name too. 174 */ 175 if ((cput = lookupname("cpu_t")) == NULL || cput->t_type != TYPEDEF) 176 return; 177 178 cpu = cput->t_tdesc; 179 if (!streq(cpu->t_name, "cpu") || cpu->t_type != STRUCT) 180 return; 181 182 for (ml = cpu->t_members, lml = NULL; ml; 183 lml = ml, ml = ml->ml_next) { 184 if (strcmp(ml->ml_name, "cpu_cyclic") == 0) 185 foundcpucyc = 1; 186 } 187 188 if (foundcpucyc == 0 || lml == NULL || 189 strcmp(lml->ml_name, "cpu_m") == 0) 190 return; 191 192 /* 193 * We need to find out how big the last element is so we can compute the 194 * offset of the new one. If the last element has a size, we use it. 195 * If it doesn't, it should be a pointer, which won't have a size. In 196 * that case, we look up the size of a long and use that as the size of 197 * the pointer. 198 */ 199 if (lml->ml_type->t_size) 200 lmlsz = lml->ml_type->t_size * NBBY; 201 else { 202 tdesc_t *tdp = lookupname("long"); 203 lmlsz = tdp->t_intr->intr_nbits; 204 } 205 206 if ((machcpu = lookupname("machcpu")) == NULL) { 207 machcpu = xcalloc(sizeof (*machcpu)); 208 machcpu->t_name = xstrdup("machcpu"); 209 machcpu->t_id = td->td_nextid++; 210 machcpu->t_type = FORWARD; 211 212 } else if (machcpu->t_type != STRUCT) 213 return; 214 215 debug(3, "Adding cpu_m machcpu %s to cpu struct\n", 216 (machcpu->t_type == FORWARD ? "forward" : "struct")); 217 218 cpum = xmalloc(sizeof (*cpum)); 219 cpum->ml_offset = lml->ml_offset + lmlsz; 220 cpum->ml_size = 0; 221 cpum->ml_name = xstrdup("cpu_m"); 222 cpum->ml_type = machcpu; 223 cpum->ml_next = NULL; 224 225 lml->ml_next = cpum; 226} 227 228/* 229 * Fix stabs generation bugs. These routines must be run before the 230 * post-conversion merge 231 */ 232void 233cvt_fixbugs(tdata_t *td) 234{ 235 fix_ptrptr_to_struct(td); 236 fix_ptr_to_struct(td); 237 fix_small_cpu_struct(td); 238} 239