Mercurial > hg > truffle
annotate src/os/bsd/vm/decoder_machO.cpp @ 15388:769fc3629f59
Add phase FlowSensitiveReductionPhase.
It is possible to remove GuardingPiNodes, CheckCastNodes, and FixedGuards during
HighTier under certain conditions (control-flow sensitive conditions).
The phase added in this commit (FlowSensitiveReductionPhase) does that,
and in addition replaces usages with "downcasting" PiNodes when possible
thus resulting in more precise object stamps (e.g., non-null).
Finally, usages of floating, side-effects free, expressions are also simplified
(as per control-flow sensitive conditions).
The newly added phase runs only during HighTier and can be deactivated
using Graal option FlowSensitiveReduction (it is active by default).
| author | Miguel Garcia <miguel.m.garcia@oracle.com> |
|---|---|
| date | Fri, 25 Apr 2014 16:50:52 +0200 |
| parents | b9a9ed0f8eeb |
| children | 78bbf4d43a14 |
| rev | line source |
|---|---|
| 4803 | 1 /* |
|
6842
b9a9ed0f8eeb
7197424: update copyright year to match last edit in jdk8 hotspot repository
mikael
parents:
6258
diff
changeset
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2 * Copyright (c) 2011, 2012, Oracle and/or its affiliates. All rights reserved. |
| 4803 | 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| 4 * | |
| 5 * This code is free software; you can redistribute it and/or modify it | |
| 6 * under the terms of the GNU General Public License version 2 only, as | |
| 7 * published by the Free Software Foundation. | |
| 8 * | |
| 9 * This code is distributed in the hope that it will be useful, but WITHOUT | |
| 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
| 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
| 12 * version 2 for more details (a copy is included in the LICENSE file that | |
| 13 * accompanied this code). | |
| 14 * | |
| 15 * You should have received a copy of the GNU General Public License version | |
| 16 * 2 along with this work; if not, write to the Free Software Foundation, | |
| 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. | |
| 18 * | |
| 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA | |
| 20 * or visit www.oracle.com if you need additional information or have any | |
| 21 * questions. | |
| 22 * | |
| 23 */ | |
| 24 | |
| 25 #include "precompiled.hpp" | |
| 26 | |
| 27 #ifdef __APPLE__ | |
| 28 #include "decoder_machO.hpp" | |
| 6258 | 29 |
| 30 #include <cxxabi.h> | |
| 31 #include <mach-o/loader.h> | |
| 32 #include <mach-o/nlist.h> | |
| 33 | |
| 34 | |
| 35 bool MachODecoder::demangle(const char* symbol, char *buf, int buflen) { | |
| 36 int status; | |
| 37 char* result; | |
| 38 size_t size = (size_t)buflen; | |
| 39 // Don't pass buf to __cxa_demangle. In case of the 'buf' is too small, | |
| 40 // __cxa_demangle will call system "realloc" for additional memory, which | |
| 41 // may use different malloc/realloc mechanism that allocates 'buf'. | |
| 42 if ((result = abi::__cxa_demangle(symbol, NULL, NULL, &status)) != NULL) { | |
| 43 jio_snprintf(buf, buflen, "%s", result); | |
| 44 // call c library's free | |
| 45 ::free(result); | |
| 46 return true; | |
| 47 } | |
| 48 return false; | |
| 49 } | |
| 50 | |
| 51 bool MachODecoder::decode(address addr, char *buf, | |
| 52 int buflen, int *offset, const void *mach_base) { | |
| 53 struct symtab_command * symt = (struct symtab_command *) | |
| 54 mach_find_command((struct mach_header_64 *)mach_base, LC_SYMTAB); | |
| 55 if (symt == NULL) { | |
| 56 DEBUG_ONLY(tty->print_cr("no symtab in mach file at 0x%lx", mach_base)); | |
| 57 return false; | |
| 58 } | |
| 59 uint32_t off = symt->symoff; /* symbol table offset (within this mach file) */ | |
| 60 uint32_t nsyms = symt->nsyms; /* number of symbol table entries */ | |
| 61 uint32_t stroff = symt->stroff; /* string table offset */ | |
| 62 uint32_t strsize = symt->strsize; /* string table size in bytes */ | |
| 63 | |
| 64 // iterate through symbol table trying to match our offset | |
| 65 | |
| 66 uint32_t addr_relative = (uintptr_t) mach_base - (uintptr_t) addr; // offset we seek in the symtab | |
| 67 void * symtab_addr = (void*) ((uintptr_t) mach_base + off); | |
| 68 struct nlist_64 *cur_nlist = (struct nlist_64 *) symtab_addr; | |
| 69 struct nlist_64 *last_nlist = cur_nlist; // no size stored in an entry, so keep previously seen nlist | |
| 70 | |
| 71 int32_t found_strx = 0; | |
| 72 int32_t found_symval = 0; | |
| 73 | |
| 74 for (uint32_t i=0; i < nsyms; i++) { | |
| 75 uint32_t this_value = cur_nlist->n_value; | |
| 76 | |
| 77 if (addr_relative == this_value) { | |
| 78 found_strx = cur_nlist->n_un.n_strx; | |
| 79 found_symval = this_value; | |
| 80 break; | |
| 81 } else if (addr_relative > this_value) { | |
| 82 // gone past it, use previously seen nlist: | |
| 83 found_strx = last_nlist->n_un.n_strx; | |
| 84 found_symval = last_nlist->n_value; | |
| 85 break; | |
| 86 } | |
| 87 last_nlist = cur_nlist; | |
| 88 cur_nlist = cur_nlist + sizeof(struct nlist_64); | |
| 89 } | |
| 90 if (found_strx == 0) { | |
| 91 return false; | |
| 92 } | |
| 93 // write the offset: | |
| 94 *offset = addr_relative - found_symval; | |
| 95 | |
| 96 // lookup found_strx in the string table | |
| 97 char * symname = mach_find_in_stringtable((char*) ((uintptr_t)mach_base + stroff), strsize, found_strx); | |
| 98 if (symname) { | |
| 99 strncpy(buf, symname, buflen); | |
| 100 return true; | |
| 101 } | |
| 102 DEBUG_ONLY(tty->print_cr("no string or null string found.")); | |
| 103 return false; | |
| 104 } | |
| 105 | |
| 106 void* MachODecoder::mach_find_command(struct mach_header_64 * mach_base, uint32_t command_wanted) { | |
| 107 // possibly verify it is a mach_header, use magic number. | |
| 108 // commands begin immediately after the header. | |
| 109 struct load_command *pos = (struct load_command *) mach_base + sizeof(struct mach_header_64); | |
| 110 for (uint32_t i = 0; i < mach_base->ncmds; i++) { | |
| 111 struct load_command *this_cmd = (struct load_command *) pos; | |
| 112 if (this_cmd->cmd == command_wanted) { | |
| 113 return pos; | |
| 114 } | |
| 115 int cmdsize = this_cmd->cmdsize; | |
| 116 pos += cmdsize; | |
| 117 } | |
| 118 return NULL; | |
| 119 } | |
| 120 | |
| 121 char* MachODecoder::mach_find_in_stringtable(char *strtab, uint32_t tablesize, int strx_wanted) { | |
| 122 | |
| 123 if (strx_wanted == 0) { | |
| 124 return NULL; | |
| 125 } | |
| 126 char *strtab_end = strtab + tablesize; | |
| 127 | |
| 128 // find the first string, skip over the space char | |
| 129 // (or the four zero bytes we see e.g. in libclient) | |
| 130 if (*strtab == ' ') { | |
| 131 strtab++; | |
| 132 if (*strtab != 0) { | |
| 133 DEBUG_ONLY(tty->print_cr("string table has leading space but no following zero.")); | |
| 134 return NULL; | |
| 135 } | |
| 136 strtab++; | |
| 137 } else { | |
| 138 if ((uint32_t) *strtab != 0) { | |
| 139 DEBUG_ONLY(tty->print_cr("string table without leading space or leading int of zero.")); | |
| 140 return NULL; | |
| 141 } | |
| 142 strtab+=4; | |
| 143 } | |
| 144 // read the real strings starting at index 1 | |
| 145 int cur_strx = 1; | |
| 146 while (strtab < strtab_end) { | |
| 147 if (cur_strx == strx_wanted) { | |
| 148 return strtab; | |
| 149 } | |
| 150 // find start of next string | |
| 151 while (*strtab != 0) { | |
| 152 strtab++; | |
| 153 } | |
| 154 strtab++; // skip the terminating zero | |
| 155 cur_strx++; | |
| 156 } | |
| 157 DEBUG_ONLY(tty->print_cr("string number %d not found.", strx_wanted)); | |
| 158 return NULL; | |
| 159 } | |
| 160 | |
| 161 | |
| 4803 | 162 #endif |
| 163 | |
| 164 |