tools/perf/util/intel-pt-decoder/intel-pt-insn-decoder.c

   1 /*
   2  * intel_pt_insn_decoder.c: Intel Processor Trace support
   3  * Copyright (c) 2013-2014, Intel Corporation.
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms and conditions of the GNU General Public License,
   7  * version 2, as published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope 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 for
  12  * more details.
  13  *
  14  */
  15
  16 #include <stdio.h>
  17 #include <string.h>
  18 #include <endian.h>
  19 #include <byteswap.h>
  20
  21 #include "event.h"
  22
  23 #include "insn.h"
  24
  25 #include "inat.c"
  26 #include "insn.c"
  27
  28 #include "intel-pt-insn-decoder.h"
  29 #include "dump-insn.h"
  30
  31 #if INTEL_PT_INSN_BUF_SZ < MAX_INSN_SIZE || INTEL_PT_INSN_BUF_SZ > MAX_INSN
  32 #error Instruction buffer size too small
  33 #endif
  34
  35 /* Based on branch_type() from arch/x86/events/intel/lbr.c */
  36 static void intel_pt_insn_decoder(struct insn *insn,
  37                                   struct intel_pt_insn *intel_pt_insn)
  38 {
  39         enum intel_pt_insn_op op = INTEL_PT_OP_OTHER;
  40         enum intel_pt_insn_branch branch = INTEL_PT_BR_NO_BRANCH;
  41         int ext;
  42
  43         intel_pt_insn->rel = 0;
  44
  45         if (insn_is_avx(insn)) {
  46                 intel_pt_insn->op = INTEL_PT_OP_OTHER;
  47                 intel_pt_insn->branch = INTEL_PT_BR_NO_BRANCH;
  48                 intel_pt_insn->length = insn->length;
  49                 return;
  50         }
  51
  52         switch (insn->opcode.bytes[0]) {
  53         case 0xf:
  54                 switch (insn->opcode.bytes[1]) {
  55                 case 0x05: /* syscall */
  56                 case 0x34: /* sysenter */
  57                         op = INTEL_PT_OP_SYSCALL;
  58                         branch = INTEL_PT_BR_INDIRECT;
  59                         break;
  60                 case 0x07: /* sysret */
  61                 case 0x35: /* sysexit */
  62                         op = INTEL_PT_OP_SYSRET;
  63                         branch = INTEL_PT_BR_INDIRECT;
  64                         break;
  65                 case 0x80 ... 0x8f: /* jcc */
  66                         op = INTEL_PT_OP_JCC;
  67                         branch = INTEL_PT_BR_CONDITIONAL;
  68                         break;
  69                 default:
  70                         break;
  71                 }
  72                 break;
  73         case 0x70 ... 0x7f: /* jcc */
  74                 op = INTEL_PT_OP_JCC;
  75                 branch = INTEL_PT_BR_CONDITIONAL;
  76                 break;
  77         case 0xc2: /* near ret */
  78         case 0xc3: /* near ret */
  79         case 0xca: /* far ret */
  80         case 0xcb: /* far ret */
  81                 op = INTEL_PT_OP_RET;
  82                 branch = INTEL_PT_BR_INDIRECT;
  83                 break;
  84         case 0xcf: /* iret */
  85                 op = INTEL_PT_OP_IRET;
  86                 branch = INTEL_PT_BR_INDIRECT;
  87                 break;
  88         case 0xcc ... 0xce: /* int */
  89                 op = INTEL_PT_OP_INT;
  90                 branch = INTEL_PT_BR_INDIRECT;
  91                 break;
  92         case 0xe8: /* call near rel */
  93                 op = INTEL_PT_OP_CALL;
  94                 branch = INTEL_PT_BR_UNCONDITIONAL;
  95                 break;
  96         case 0x9a: /* call far absolute */
  97                 op = INTEL_PT_OP_CALL;
  98                 branch = INTEL_PT_BR_INDIRECT;
  99                 break;
 100         case 0xe0 ... 0xe2: /* loop */
 101                 op = INTEL_PT_OP_LOOP;
 102                 branch = INTEL_PT_BR_CONDITIONAL;
 103                 break;
 104         case 0xe3: /* jcc */
 105                 op = INTEL_PT_OP_JCC;
 106                 branch = INTEL_PT_BR_CONDITIONAL;
 107                 break;
 108         case 0xe9: /* jmp */
 109         case 0xeb: /* jmp */
 110                 op = INTEL_PT_OP_JMP;
 111                 branch = INTEL_PT_BR_UNCONDITIONAL;
 112                 break;
 113         case 0xea: /* far jmp */
 114                 op = INTEL_PT_OP_JMP;
 115                 branch = INTEL_PT_BR_INDIRECT;
 116                 break;
 117         case 0xff: /* call near absolute, call far absolute ind */
 118                 ext = (insn->modrm.bytes[0] >> 3) & 0x7;
 119                 switch (ext) {
 120                 case 2: /* near ind call */
 121                 case 3: /* far ind call */
 122                         op = INTEL_PT_OP_CALL;
 123                         branch = INTEL_PT_BR_INDIRECT;
 124                         break;
 125                 case 4:
 126                 case 5:
 127                         op = INTEL_PT_OP_JMP;
 128                         branch = INTEL_PT_BR_INDIRECT;
 129                         break;
 130                 default:
 131                         break;
 132                 }
 133                 break;
 134         default:
 135                 break;
 136         }
 137
 138         intel_pt_insn->op = op;
 139         intel_pt_insn->branch = branch;
 140         intel_pt_insn->length = insn->length;
 141
 142         if (branch == INTEL_PT_BR_CONDITIONAL ||
 143             branch == INTEL_PT_BR_UNCONDITIONAL) {
 144 #if __BYTE_ORDER == __BIG_ENDIAN
 145                 switch (insn->immediate.nbytes) {
 146                 case 1:
 147                         intel_pt_insn->rel = insn->immediate.value;
 148                         break;
 149                 case 2:
 150                         intel_pt_insn->rel =
 151                                         bswap_16((short)insn->immediate.value);
 152                         break;
 153                 case 4:
 154                         intel_pt_insn->rel = bswap_32(insn->immediate.value);
 155                         break;
 156                 default:
 157                         intel_pt_insn->rel = 0;
 158                         break;
 159                 }
 160 #else
 161                 intel_pt_insn->rel = insn->immediate.value;
 162 #endif
 163         }
 164 }
 165
 166 int intel_pt_get_insn(const unsigned char *buf, size_t len, int x86_64,
 167                       struct intel_pt_insn *intel_pt_insn)
 168 {
 169         struct insn insn;
 170
 171         insn_init(&insn, buf, len, x86_64);
 172         insn_get_length(&insn);
 173         if (!insn_complete(&insn) || insn.length > len)
 174                 return -1;
 175         intel_pt_insn_decoder(&insn, intel_pt_insn);
 176         if (insn.length < INTEL_PT_INSN_BUF_SZ)
 177                 memcpy(intel_pt_insn->buf, buf, insn.length);
 178         else
 179                 memcpy(intel_pt_insn->buf, buf, INTEL_PT_INSN_BUF_SZ);
 180         return 0;
 181 }
 182
 183 int arch_is_branch(const unsigned char *buf, size_t len, int x86_64)
 184 {
 185         struct intel_pt_insn in;
 186         if (intel_pt_get_insn(buf, len, x86_64, &in) < 0)
 187                 return -1;
 188         return in.branch != INTEL_PT_BR_NO_BRANCH;
 189 }
 190
 191 const char *dump_insn(struct perf_insn *x, uint64_t ip __maybe_unused,
 192                       u8 *inbuf, int inlen, int *lenp)
 193 {
 194         struct insn insn;
 195         int n, i;
 196         int left;
 197
 198         insn_init(&insn, inbuf, inlen, x->is64bit);
 199         insn_get_length(&insn);
 200         if (!insn_complete(&insn) || insn.length > inlen)
 201                 return "<bad>";
 202         if (lenp)
 203                 *lenp = insn.length;
 204         left = sizeof(x->out);
 205         n = snprintf(x->out, left, "insn: ");
 206         left -= n;
 207         for (i = 0; i < insn.length; i++) {
 208                 n += snprintf(x->out + n, left, "%02x ", inbuf[i]);
 209                 left -= n;
 210         }
 211         return x->out;
 212 }
 213
 214 const char *branch_name[] = {
 215         [INTEL_PT_OP_OTHER]     = "Other",
 216         [INTEL_PT_OP_CALL]      = "Call",
 217         [INTEL_PT_OP_RET]       = "Ret",
 218         [INTEL_PT_OP_JCC]       = "Jcc",
 219         [INTEL_PT_OP_JMP]       = "Jmp",
 220         [INTEL_PT_OP_LOOP]      = "Loop",
 221         [INTEL_PT_OP_IRET]      = "IRet",
 222         [INTEL_PT_OP_INT]       = "Int",
 223         [INTEL_PT_OP_SYSCALL]   = "Syscall",
 224         [INTEL_PT_OP_SYSRET]    = "Sysret",
 225 };
 226
 227 const char *intel_pt_insn_name(enum intel_pt_insn_op op)
 228 {
 229         return branch_name[op];
 230 }
 231
 232 int intel_pt_insn_desc(const struct intel_pt_insn *intel_pt_insn, char *buf,
 233                        size_t buf_len)
 234 {
 235         switch (intel_pt_insn->branch) {
 236         case INTEL_PT_BR_CONDITIONAL:
 237         case INTEL_PT_BR_UNCONDITIONAL:
 238                 return snprintf(buf, buf_len, "%s %s%d",
 239                                 intel_pt_insn_name(intel_pt_insn->op),
 240                                 intel_pt_insn->rel > 0 ? "+" : "",
 241                                 intel_pt_insn->rel);
 242         case INTEL_PT_BR_NO_BRANCH:
 243         case INTEL_PT_BR_INDIRECT:
 244                 return snprintf(buf, buf_len, "%s",
 245                                 intel_pt_insn_name(intel_pt_insn->op));
 246         default:
 247                 break;
 248         }
 249         return 0;
 250 }
 251
 252 int intel_pt_insn_type(enum intel_pt_insn_op op)
 253 {
 254         switch (op) {
 255         case INTEL_PT_OP_OTHER:
 256                 return 0;
 257         case INTEL_PT_OP_CALL:
 258                 return PERF_IP_FLAG_BRANCH | PERF_IP_FLAG_CALL;
 259         case INTEL_PT_OP_RET:
 260                 return PERF_IP_FLAG_BRANCH | PERF_IP_FLAG_RETURN;
 261         case INTEL_PT_OP_JCC:
 262                 return PERF_IP_FLAG_BRANCH | PERF_IP_FLAG_CONDITIONAL;
 263         case INTEL_PT_OP_JMP:
 264                 return PERF_IP_FLAG_BRANCH;
 265         case INTEL_PT_OP_LOOP:
 266                 return PERF_IP_FLAG_BRANCH | PERF_IP_FLAG_CONDITIONAL;
 267         case INTEL_PT_OP_IRET:
 268                 return PERF_IP_FLAG_BRANCH | PERF_IP_FLAG_RETURN |
 269                        PERF_IP_FLAG_INTERRUPT;
 270         case INTEL_PT_OP_INT:
 271                 return PERF_IP_FLAG_BRANCH | PERF_IP_FLAG_CALL |
 272                        PERF_IP_FLAG_INTERRUPT;
 273         case INTEL_PT_OP_SYSCALL:
 274                 return PERF_IP_FLAG_BRANCH | PERF_IP_FLAG_CALL |
 275                        PERF_IP_FLAG_SYSCALLRET;
 276         case INTEL_PT_OP_SYSRET:
 277                 return PERF_IP_FLAG_BRANCH | PERF_IP_FLAG_RETURN |
 278                        PERF_IP_FLAG_SYSCALLRET;
 279         default:
 280                 return 0;
 281         }
 282 }