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 /* Based on branch_type() from perf_event_intel_lbr.c */
31 static void intel_pt_insn_decoder(struct insn *insn,
32 struct intel_pt_insn *intel_pt_insn)
34 enum intel_pt_insn_op op = INTEL_PT_OP_OTHER;
35 enum intel_pt_insn_branch branch = INTEL_PT_BR_NO_BRANCH;
38 if (insn_is_avx(insn)) {
39 intel_pt_insn->op = INTEL_PT_OP_OTHER;
40 intel_pt_insn->branch = INTEL_PT_BR_NO_BRANCH;
41 intel_pt_insn->length = insn->length;
45 switch (insn->opcode.bytes[0]) {
47 switch (insn->opcode.bytes[1]) {
48 case 0x05: /* syscall */
49 case 0x34: /* sysenter */
50 op = INTEL_PT_OP_SYSCALL;
51 branch = INTEL_PT_BR_INDIRECT;
53 case 0x07: /* sysret */
54 case 0x35: /* sysexit */
55 op = INTEL_PT_OP_SYSRET;
56 branch = INTEL_PT_BR_INDIRECT;
58 case 0x80 ... 0x8f: /* jcc */
60 branch = INTEL_PT_BR_CONDITIONAL;
66 case 0x70 ... 0x7f: /* jcc */
68 branch = INTEL_PT_BR_CONDITIONAL;
70 case 0xc2: /* near ret */
71 case 0xc3: /* near ret */
72 case 0xca: /* far ret */
73 case 0xcb: /* far ret */
75 branch = INTEL_PT_BR_INDIRECT;
78 op = INTEL_PT_OP_IRET;
79 branch = INTEL_PT_BR_INDIRECT;
81 case 0xcc ... 0xce: /* int */
83 branch = INTEL_PT_BR_INDIRECT;
85 case 0xe8: /* call near rel */
86 op = INTEL_PT_OP_CALL;
87 branch = INTEL_PT_BR_UNCONDITIONAL;
89 case 0x9a: /* call far absolute */
90 op = INTEL_PT_OP_CALL;
91 branch = INTEL_PT_BR_INDIRECT;
93 case 0xe0 ... 0xe2: /* loop */
94 op = INTEL_PT_OP_LOOP;
95 branch = INTEL_PT_BR_CONDITIONAL;
99 branch = INTEL_PT_BR_CONDITIONAL;
103 op = INTEL_PT_OP_JMP;
104 branch = INTEL_PT_BR_UNCONDITIONAL;
106 case 0xea: /* far jmp */
107 op = INTEL_PT_OP_JMP;
108 branch = INTEL_PT_BR_INDIRECT;
110 case 0xff: /* call near absolute, call far absolute ind */
111 ext = (insn->modrm.bytes[0] >> 3) & 0x7;
113 case 2: /* near ind call */
114 case 3: /* far ind call */
115 op = INTEL_PT_OP_CALL;
116 branch = INTEL_PT_BR_INDIRECT;
120 op = INTEL_PT_OP_JMP;
121 branch = INTEL_PT_BR_INDIRECT;
131 intel_pt_insn->op = op;
132 intel_pt_insn->branch = branch;
133 intel_pt_insn->length = insn->length;
135 if (branch == INTEL_PT_BR_CONDITIONAL ||
136 branch == INTEL_PT_BR_UNCONDITIONAL) {
137 #if __BYTE_ORDER == __BIG_ENDIAN
138 switch (insn->immediate.nbytes) {
140 intel_pt_insn->rel = insn->immediate.value;
144 bswap_16((short)insn->immediate.value);
147 intel_pt_insn->rel = bswap_32(insn->immediate.value);
150 intel_pt_insn->rel = 0;
154 intel_pt_insn->rel = insn->immediate.value;
159 int intel_pt_get_insn(const unsigned char *buf, size_t len, int x86_64,
160 struct intel_pt_insn *intel_pt_insn)
164 insn_init(&insn, buf, len, x86_64);
165 insn_get_length(&insn);
166 if (!insn_complete(&insn) || insn.length > len)
168 intel_pt_insn_decoder(&insn, intel_pt_insn);
169 if (insn.length < INTEL_PT_INSN_DBG_BUF_SZ)
170 memcpy(intel_pt_insn->buf, buf, insn.length);
172 memcpy(intel_pt_insn->buf, buf, INTEL_PT_INSN_DBG_BUF_SZ);
176 const char *branch_name[] = {
177 [INTEL_PT_OP_OTHER] = "Other",
178 [INTEL_PT_OP_CALL] = "Call",
179 [INTEL_PT_OP_RET] = "Ret",
180 [INTEL_PT_OP_JCC] = "Jcc",
181 [INTEL_PT_OP_JMP] = "Jmp",
182 [INTEL_PT_OP_LOOP] = "Loop",
183 [INTEL_PT_OP_IRET] = "IRet",
184 [INTEL_PT_OP_INT] = "Int",
185 [INTEL_PT_OP_SYSCALL] = "Syscall",
186 [INTEL_PT_OP_SYSRET] = "Sysret",
189 const char *intel_pt_insn_name(enum intel_pt_insn_op op)
191 return branch_name[op];
194 int intel_pt_insn_desc(const struct intel_pt_insn *intel_pt_insn, char *buf,
197 switch (intel_pt_insn->branch) {
198 case INTEL_PT_BR_CONDITIONAL:
199 case INTEL_PT_BR_UNCONDITIONAL:
200 return snprintf(buf, buf_len, "%s %s%d",
201 intel_pt_insn_name(intel_pt_insn->op),
202 intel_pt_insn->rel > 0 ? "+" : "",
204 case INTEL_PT_BR_NO_BRANCH:
205 case INTEL_PT_BR_INDIRECT:
206 return snprintf(buf, buf_len, "%s",
207 intel_pt_insn_name(intel_pt_insn->op));
214 size_t intel_pt_insn_max_size(void)
216 return MAX_INSN_SIZE;
219 int intel_pt_insn_type(enum intel_pt_insn_op op)
222 case INTEL_PT_OP_OTHER:
224 case INTEL_PT_OP_CALL:
225 return PERF_IP_FLAG_BRANCH | PERF_IP_FLAG_CALL;
226 case INTEL_PT_OP_RET:
227 return PERF_IP_FLAG_BRANCH | PERF_IP_FLAG_RETURN;
228 case INTEL_PT_OP_JCC:
229 return PERF_IP_FLAG_BRANCH | PERF_IP_FLAG_CONDITIONAL;
230 case INTEL_PT_OP_JMP:
231 return PERF_IP_FLAG_BRANCH;
232 case INTEL_PT_OP_LOOP:
233 return PERF_IP_FLAG_BRANCH | PERF_IP_FLAG_CONDITIONAL;
234 case INTEL_PT_OP_IRET:
235 return PERF_IP_FLAG_BRANCH | PERF_IP_FLAG_RETURN |
236 PERF_IP_FLAG_INTERRUPT;
237 case INTEL_PT_OP_INT:
238 return PERF_IP_FLAG_BRANCH | PERF_IP_FLAG_CALL |
239 PERF_IP_FLAG_INTERRUPT;
240 case INTEL_PT_OP_SYSCALL:
241 return PERF_IP_FLAG_BRANCH | PERF_IP_FLAG_CALL |
242 PERF_IP_FLAG_SYSCALLRET;
243 case INTEL_PT_OP_SYSRET:
244 return PERF_IP_FLAG_BRANCH | PERF_IP_FLAG_RETURN |
245 PERF_IP_FLAG_SYSCALLRET;