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 (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright 2006 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 26 #pragma ident "%Z%%M% %I% %E% SMI" 27 28 /* 29 * Workarounds for stabs generation bugs in the compiler and general needed 30 * fixups. 31 */ 32 33 #if HAVE_NBTOOL_CONFIG_H 34 # include "nbtool_config.h" 35 #endif 36 37 #include <stdio.h> 38 #include <strings.h> 39 40 #include "ctf_headers.h" 41 #include "ctftools.h" 42 #include "hash.h" 43 #include "memory.h" 44 #include "traverse.h" 45 46 /* 47 * Due to 4432619, the 6.1 compiler will sometimes incorrectly generate pointer 48 * stabs. Given a struct foo, and a corresponding typedef struct foo foo_t. 49 * In some cases, when faced with a pointer to a foo_t, the compiler will 50 * sometimes generate a stab that describes a pointer to a struct foo. 51 * Regardless of correctness, this breaks merges, as it occurs inconsistently 52 * by file. The following two routines know how to recognize and repair foo_t * 53 * and foo_t ** bugs in a specific set of cases. There is no general way to 54 * solve this problem without a fix to the compiler. In general, cases should 55 * only be added to these routines to fix merging problems in genunix. 56 */ 57 static void 58 fix_ptrptr_to_struct(tdata_t *td) 59 { 60 const char *strs[2] = { "as", "fdbuffer" }; 61 const char *mems[2] = { "a_objectdir", "fd_shadow" }; 62 const char *acts[2] = { "vnode", "page" }; 63 const char *tgts[2] = { "vnode_t", "page_t" }; 64 tdesc_t *str; 65 tdesc_t *act, *tgt; 66 tdesc_t *p1, *p2; 67 mlist_t *ml; 68 int i; 69 70 for (i = 0; i < (int) (sizeof (strs) / sizeof (strs[0])); i++) { 71 if (!(str = lookupname(strs[i])) || str->t_type != STRUCT) 72 continue; 73 74 for (ml = str->t_members; ml; ml = ml->ml_next) { 75 if (streq(ml->ml_name, mems[i])) 76 break; 77 } 78 if (!ml) 79 continue; 80 81 if (ml->ml_type->t_type != POINTER || ml->ml_type->t_name || 82 ml->ml_type->t_tdesc->t_type != POINTER || 83 ml->ml_type->t_tdesc->t_name) 84 continue; 85 86 act = ml->ml_type->t_tdesc->t_tdesc; 87 if (act->t_type != STRUCT || !streq(act->t_name, acts[i])) 88 continue; 89 90 if (!(tgt = lookupname(tgts[i])) || tgt->t_type != TYPEDEF) 91 continue; 92 93 /* We have an instance of the bug */ 94 p2 = xcalloc(sizeof (*p2)); 95 p2->t_type = POINTER; 96 p2->t_id = td->td_nextid++; 97 p2->t_tdesc = tgt; 98 99 p1 = xcalloc(sizeof (*p1)); 100 p1->t_type = POINTER; 101 p1->t_id = td->td_nextid++; 102 p1->t_tdesc = p2; 103 104 ml->ml_type = p1; 105 106 debug(3, "Fixed %s->%s => ptrptr struct %s bug\n", 107 strs[i], mems[i], acts[i]); 108 } 109 } 110 111 static void 112 fix_ptr_to_struct(tdata_t *td) 113 { 114 const char *strs[2] = { "vmem", "id_space" }; 115 const char *mems[2] = { NULL, "is_vmem" }; 116 tdesc_t *ptr = NULL; 117 tdesc_t *str, *vmt; 118 mlist_t *ml; 119 int i; 120 121 if ((vmt = lookupname("vmem_t")) == NULL || vmt->t_type != TYPEDEF) 122 return; 123 124 for (i = 0; i < (int) (sizeof (strs) / sizeof (strs[0])); i++) { 125 if (!(str = lookupname(strs[i])) || str->t_type != STRUCT) 126 continue; 127 128 for (ml = str->t_members; ml; ml = ml->ml_next) { 129 if (mems[i] && !streq(ml->ml_name, mems[i])) 130 continue; 131 132 if (ml->ml_type->t_type != POINTER || 133 ml->ml_type->t_name || 134 (ml->ml_type->t_tdesc->t_type != STRUCT && 135 ml->ml_type->t_tdesc->t_type != FORWARD) || 136 !streq(ml->ml_type->t_tdesc->t_name, "vmem")) 137 continue; 138 139 debug(3, "Fixed %s->%s => ptr struct vmem bug\n", 140 strs[i], ml->ml_name); 141 142 if (!ptr) { 143 ptr = xcalloc(sizeof (*ptr)); 144 ptr->t_type = POINTER; 145 ptr->t_id = td->td_nextid++; 146 ptr->t_tdesc = vmt; 147 } 148 149 ml->ml_type = ptr; 150 } 151 } 152 } 153 154 /* 155 * Fix stabs generation bugs. These routines must be run before the 156 * post-conversion merge 157 */ 158 void 159 cvt_fixstabs(tdata_t *td) 160 { 161 fix_ptrptr_to_struct(td); 162 fix_ptr_to_struct(td); 163 } 164 165 struct match { 166 tdesc_t *m_ret; 167 const char *m_name; 168 }; 169 170 static int 171 matching_iidesc(void *arg1, void *arg2) 172 { 173 iidesc_t *iidesc = arg1; 174 struct match *match = arg2; 175 if (!streq(iidesc->ii_name, match->m_name)) 176 return (0); 177 178 if (iidesc->ii_type != II_TYPE && iidesc->ii_type != II_SOU) 179 return (0); 180 181 match->m_ret = iidesc->ii_dtype; 182 return (-1); 183 } 184 185 static tdesc_t * 186 lookup_tdesc(tdata_t *td, char const *name) 187 { 188 struct match match = { NULL, name }; 189 iter_iidescs_by_name(td, name, matching_iidesc, &match); 190 return (match.m_ret); 191 } 192 193 /* 194 * The cpu structure grows, with the addition of a machcpu member, if 195 * _MACHDEP is defined. This means that, for example, the cpu structure 196 * in unix is different from the cpu structure in genunix. As one might 197 * expect, this causes merges to fail. Since everyone indirectly contains 198 * a pointer to a CPU structure, the failed merges can cause massive amounts 199 * of duplication. In the case of unix uniquifying against genunix, upwards 200 * of 50% of the structures were unmerged due to this problem. We fix this 201 * by adding a cpu_m member. If machcpu hasn't been defined in our module, 202 * we make a forward node for it. 203 */ 204 static void 205 fix_small_cpu_struct(tdata_t *td, size_t ptrsize) 206 { 207 tdesc_t *cput, *cpu; 208 tdesc_t *machcpu; 209 mlist_t *ml, *lml; 210 mlist_t *cpum; 211 int foundcpucyc = 0; 212 213 /* 214 * We're going to take the circuitous route finding the cpu structure, 215 * because we want to make sure that we find the right one. It would 216 * be nice if we could verify the header name too. DWARF might not 217 * have the cpu_t, so we let this pass. 218 */ 219 if ((cput = lookup_tdesc(td, "cpu_t")) != NULL) { 220 if (cput->t_type != TYPEDEF) 221 return; 222 cpu = cput->t_tdesc; 223 } else { 224 cpu = lookup_tdesc(td, "cpu"); 225 } 226 227 if (cpu == NULL) 228 return; 229 230 if (!streq(cpu->t_name, "cpu") || cpu->t_type != STRUCT) 231 return; 232 233 for (ml = cpu->t_members, lml = NULL; ml; 234 lml = ml, ml = ml->ml_next) { 235 if (strcmp(ml->ml_name, "cpu_cyclic") == 0) 236 foundcpucyc = 1; 237 } 238 239 if (foundcpucyc == 0 || lml == NULL || 240 strcmp(lml->ml_name, "cpu_m") == 0) 241 return; 242 243 /* 244 * We need to derive the right offset for the fake cpu_m member. To do 245 * that, we require a special unused member to be the last member 246 * before the 'cpu_m', that we encode knowledge of here. ABI alignment 247 * on all platforms is such that we only need to add a pointer-size 248 * number of bits to get the right offset for cpu_m. This would most 249 * likely break if gcc's -malign-double were ever used, but that option 250 * breaks the ABI anyway. 251 */ 252 if (!streq(lml->ml_name, "cpu_m_pad") && 253 getenv("CTFCONVERT_PERMISSIVE") == NULL) { 254 terminate("last cpu_t member before cpu_m is %s; " 255 "it must be cpu_m_pad.\n", lml->ml_name); 256 } 257 258 if ((machcpu = lookup_tdesc(td, "machcpu")) == NULL) { 259 machcpu = xcalloc(sizeof (*machcpu)); 260 machcpu->t_name = xstrdup("machcpu"); 261 machcpu->t_id = td->td_nextid++; 262 machcpu->t_type = FORWARD; 263 } else if (machcpu->t_type != STRUCT) { 264 return; 265 } 266 267 debug(3, "Adding cpu_m machcpu %s to cpu struct\n", 268 (machcpu->t_type == FORWARD ? "forward" : "struct")); 269 270 cpum = xmalloc(sizeof (*cpum)); 271 cpum->ml_offset = lml->ml_offset + (ptrsize * NBBY); 272 cpum->ml_size = 0; 273 cpum->ml_name = xstrdup("cpu_m"); 274 cpum->ml_type = machcpu; 275 cpum->ml_next = NULL; 276 277 lml->ml_next = cpum; 278 } 279 280 #ifdef __NetBSD__ 281 282 /* 283 * XXX: A crude hack to bring down the number of types for a 284 * GENERIC kernel below 2**15-1 (from ~34000 to ~29800). 285 * 286 * Remove the type attributes "volatile", "const" and "restrict", 287 * for DTRACE these attributes are of little value. 288 */ 289 290 static int 291 fix_kill_attr_cb(tdesc_t *tdp, tdesc_t **tdpp, void *private __unused) 292 { 293 294 while (tdp->t_type == VOLATILE || 295 tdp->t_type == RESTRICT || 296 tdp->t_type == CONST) 297 tdp = tdp->t_tdesc; 298 299 *tdpp = tdp; 300 301 return 1; 302 } 303 304 static tdtrav_cb_f fix_kill_attr_tab[] = { 305 NULL, 306 NULL, /* intrinsic */ 307 NULL, /* pointer */ 308 NULL, /* reference */ 309 NULL, /* array */ 310 NULL, /* function */ 311 NULL, /* struct */ 312 NULL, /* union */ 313 NULL, /* class */ 314 NULL, /* enum */ 315 NULL , /* forward */ 316 NULL, /* typedef */ 317 NULL, /* typedef unres */ 318 fix_kill_attr_cb, /* volatile */ 319 fix_kill_attr_cb, /* const */ 320 fix_kill_attr_cb, /* restrict */ 321 }; 322 323 static void 324 fix_kill_attr(tdata_t *td, size_t ptrsize) 325 { 326 327 (void) iitraverse_hash(td->td_iihash, &td->td_curvgen, 328 fix_kill_attr_tab, NULL, NULL, NULL); 329 } 330 331 #endif /* __NetBSD__ */ 332 333 void 334 cvt_fixups(tdata_t *td, size_t ptrsize) 335 { 336 fix_small_cpu_struct(td, ptrsize); 337 #ifdef __NetBSD__ 338 fix_kill_attr(td, ptrsize); 339 #endif 340 } 341