2 * intel_pt_insn_decoder.c: Intel Processor Trace support
3 * Copyright (c) 2013-2014, Intel Corporation.
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.
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
28 #include "intel-pt-insn-decoder.h"
30 #if INTEL_PT_INSN_BUF_SZ < MAX_INSN_SIZE || INTEL_PT_INSN_BUF_SZ > MAX_INSN
31 #error Instruction buffer size too small
34 /* Based on branch_type() from arch/x86/events/intel/lbr.c */
35 static void intel_pt_insn_decoder(struct insn *insn,
36 struct intel_pt_insn *intel_pt_insn)
38 enum intel_pt_insn_op op = INTEL_PT_OP_OTHER;
39 enum intel_pt_insn_branch branch = INTEL_PT_BR_NO_BRANCH;
42 if (insn_is_avx(insn)) {
43 intel_pt_insn->op = INTEL_PT_OP_OTHER;
44 intel_pt_insn->branch = INTEL_PT_BR_NO_BRANCH;
45 intel_pt_insn->length = insn->length;
49 switch (insn->opcode.bytes[0]) {
51 switch (insn->opcode.bytes[1]) {
52 case 0x05: /* syscall */
53 case 0x34: /* sysenter */
54 op = INTEL_PT_OP_SYSCALL;
55 branch = INTEL_PT_BR_INDIRECT;
57 case 0x07: /* sysret */
58 case 0x35: /* sysexit */
59 op = INTEL_PT_OP_SYSRET;
60 branch = INTEL_PT_BR_INDIRECT;
62 case 0x80 ... 0x8f: /* jcc */
64 branch = INTEL_PT_BR_CONDITIONAL;
70 case 0x70 ... 0x7f: /* jcc */
72 branch = INTEL_PT_BR_CONDITIONAL;
74 case 0xc2: /* near ret */
75 case 0xc3: /* near ret */
76 case 0xca: /* far ret */
77 case 0xcb: /* far ret */
79 branch = INTEL_PT_BR_INDIRECT;
82 op = INTEL_PT_OP_IRET;
83 branch = INTEL_PT_BR_INDIRECT;
85 case 0xcc ... 0xce: /* int */
87 branch = INTEL_PT_BR_INDIRECT;
89 case 0xe8: /* call near rel */
90 op = INTEL_PT_OP_CALL;
91 branch = INTEL_PT_BR_UNCONDITIONAL;
93 case 0x9a: /* call far absolute */
94 op = INTEL_PT_OP_CALL;
95 branch = INTEL_PT_BR_INDIRECT;
97 case 0xe0 ... 0xe2: /* loop */
98 op = INTEL_PT_OP_LOOP;
99 branch = INTEL_PT_BR_CONDITIONAL;
102 op = INTEL_PT_OP_JCC;
103 branch = INTEL_PT_BR_CONDITIONAL;
107 op = INTEL_PT_OP_JMP;
108 branch = INTEL_PT_BR_UNCONDITIONAL;
110 case 0xea: /* far jmp */
111 op = INTEL_PT_OP_JMP;
112 branch = INTEL_PT_BR_INDIRECT;
114 case 0xff: /* call near absolute, call far absolute ind */
115 ext = (insn->modrm.bytes[0] >> 3) & 0x7;
117 case 2: /* near ind call */
118 case 3: /* far ind call */
119 op = INTEL_PT_OP_CALL;
120 branch = INTEL_PT_BR_INDIRECT;
124 op = INTEL_PT_OP_JMP;
125 branch = INTEL_PT_BR_INDIRECT;
135 intel_pt_insn->op = op;
136 intel_pt_insn->branch = branch;
137 intel_pt_insn->length = insn->length;
139 if (branch == INTEL_PT_BR_CONDITIONAL ||
140 branch == INTEL_PT_BR_UNCONDITIONAL) {
141 #if __BYTE_ORDER == __BIG_ENDIAN
142 switch (insn->immediate.nbytes) {
144 intel_pt_insn->rel = insn->immediate.value;
148 bswap_16((short)insn->immediate.value);
151 intel_pt_insn->rel = bswap_32(insn->immediate.value);
154 intel_pt_insn->rel = 0;
158 intel_pt_insn->rel = insn->immediate.value;
163 int intel_pt_get_insn(const unsigned char *buf, size_t len, int x86_64,
164 struct intel_pt_insn *intel_pt_insn)
168 insn_init(&insn, buf, len, x86_64);
169 insn_get_length(&insn);
170 if (!insn_complete(&insn) || insn.length > len)
172 intel_pt_insn_decoder(&insn, intel_pt_insn);
173 if (insn.length < INTEL_PT_INSN_BUF_SZ)
174 memcpy(intel_pt_insn->buf, buf, insn.length);
176 memcpy(intel_pt_insn->buf, buf, INTEL_PT_INSN_BUF_SZ);
180 const char *branch_name[] = {
181 [INTEL_PT_OP_OTHER] = "Other",
182 [INTEL_PT_OP_CALL] = "Call",
183 [INTEL_PT_OP_RET] = "Ret",
184 [INTEL_PT_OP_JCC] = "Jcc",
185 [INTEL_PT_OP_JMP] = "Jmp",
186 [INTEL_PT_OP_LOOP] = "Loop",
187 [INTEL_PT_OP_IRET] = "IRet",
188 [INTEL_PT_OP_INT] = "Int",
189 [INTEL_PT_OP_SYSCALL] = "Syscall",
190 [INTEL_PT_OP_SYSRET] = "Sysret",
193 const char *intel_pt_insn_name(enum intel_pt_insn_op op)
195 return branch_name[op];
198 int intel_pt_insn_desc(const struct intel_pt_insn *intel_pt_insn, char *buf,
201 switch (intel_pt_insn->branch) {
202 case INTEL_PT_BR_CONDITIONAL:
203 case INTEL_PT_BR_UNCONDITIONAL:
204 return snprintf(buf, buf_len, "%s %s%d",
205 intel_pt_insn_name(intel_pt_insn->op),
206 intel_pt_insn->rel > 0 ? "+" : "",
208 case INTEL_PT_BR_NO_BRANCH:
209 case INTEL_PT_BR_INDIRECT:
210 return snprintf(buf, buf_len, "%s",
211 intel_pt_insn_name(intel_pt_insn->op));
218 int intel_pt_insn_type(enum intel_pt_insn_op op)
221 case INTEL_PT_OP_OTHER:
223 case INTEL_PT_OP_CALL:
224 return PERF_IP_FLAG_BRANCH | PERF_IP_FLAG_CALL;
225 case INTEL_PT_OP_RET:
226 return PERF_IP_FLAG_BRANCH | PERF_IP_FLAG_RETURN;
227 case INTEL_PT_OP_JCC:
228 return PERF_IP_FLAG_BRANCH | PERF_IP_FLAG_CONDITIONAL;
229 case INTEL_PT_OP_JMP:
230 return PERF_IP_FLAG_BRANCH;
231 case INTEL_PT_OP_LOOP:
232 return PERF_IP_FLAG_BRANCH | PERF_IP_FLAG_CONDITIONAL;
233 case INTEL_PT_OP_IRET:
234 return PERF_IP_FLAG_BRANCH | PERF_IP_FLAG_RETURN |
235 PERF_IP_FLAG_INTERRUPT;
236 case INTEL_PT_OP_INT:
237 return PERF_IP_FLAG_BRANCH | PERF_IP_FLAG_CALL |
238 PERF_IP_FLAG_INTERRUPT;
239 case INTEL_PT_OP_SYSCALL:
240 return PERF_IP_FLAG_BRANCH | PERF_IP_FLAG_CALL |
241 PERF_IP_FLAG_SYSCALLRET;
242 case INTEL_PT_OP_SYSRET:
243 return PERF_IP_FLAG_BRANCH | PERF_IP_FLAG_RETURN |
244 PERF_IP_FLAG_SYSCALLRET;