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
30 /* Based on branch_type() from perf_event_intel_lbr.c */
intel_pt_insn_decoder(struct insn * insn,struct intel_pt_insn * intel_pt_insn)31 static void intel_pt_insn_decoder(struct insn *insn,
32 struct intel_pt_insn *intel_pt_insn)
33 {
34 enum intel_pt_insn_op op = INTEL_PT_OP_OTHER;
35 enum intel_pt_insn_branch branch = INTEL_PT_BR_NO_BRANCH;
36 int ext;
37
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;
42 return;
43 }
44
45 switch (insn->opcode.bytes[0]) {
46 case 0xf:
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;
52 break;
53 case 0x07: /* sysret */
54 case 0x35: /* sysexit */
55 op = INTEL_PT_OP_SYSRET;
56 branch = INTEL_PT_BR_INDIRECT;
57 break;
58 case 0x80 ... 0x8f: /* jcc */
59 op = INTEL_PT_OP_JCC;
60 branch = INTEL_PT_BR_CONDITIONAL;
61 break;
62 default:
63 break;
64 }
65 break;
66 case 0x70 ... 0x7f: /* jcc */
67 op = INTEL_PT_OP_JCC;
68 branch = INTEL_PT_BR_CONDITIONAL;
69 break;
70 case 0xc2: /* near ret */
71 case 0xc3: /* near ret */
72 case 0xca: /* far ret */
73 case 0xcb: /* far ret */
74 op = INTEL_PT_OP_RET;
75 branch = INTEL_PT_BR_INDIRECT;
76 break;
77 case 0xcf: /* iret */
78 op = INTEL_PT_OP_IRET;
79 branch = INTEL_PT_BR_INDIRECT;
80 break;
81 case 0xcc ... 0xce: /* int */
82 op = INTEL_PT_OP_INT;
83 branch = INTEL_PT_BR_INDIRECT;
84 break;
85 case 0xe8: /* call near rel */
86 op = INTEL_PT_OP_CALL;
87 branch = INTEL_PT_BR_UNCONDITIONAL;
88 break;
89 case 0x9a: /* call far absolute */
90 op = INTEL_PT_OP_CALL;
91 branch = INTEL_PT_BR_INDIRECT;
92 break;
93 case 0xe0 ... 0xe2: /* loop */
94 op = INTEL_PT_OP_LOOP;
95 branch = INTEL_PT_BR_CONDITIONAL;
96 break;
97 case 0xe3: /* jcc */
98 op = INTEL_PT_OP_JCC;
99 branch = INTEL_PT_BR_CONDITIONAL;
100 break;
101 case 0xe9: /* jmp */
102 case 0xeb: /* jmp */
103 op = INTEL_PT_OP_JMP;
104 branch = INTEL_PT_BR_UNCONDITIONAL;
105 break;
106 case 0xea: /* far jmp */
107 op = INTEL_PT_OP_JMP;
108 branch = INTEL_PT_BR_INDIRECT;
109 break;
110 case 0xff: /* call near absolute, call far absolute ind */
111 ext = (insn->modrm.bytes[0] >> 3) & 0x7;
112 switch (ext) {
113 case 2: /* near ind call */
114 case 3: /* far ind call */
115 op = INTEL_PT_OP_CALL;
116 branch = INTEL_PT_BR_INDIRECT;
117 break;
118 case 4:
119 case 5:
120 op = INTEL_PT_OP_JMP;
121 branch = INTEL_PT_BR_INDIRECT;
122 break;
123 default:
124 break;
125 }
126 break;
127 default:
128 break;
129 }
130
131 intel_pt_insn->op = op;
132 intel_pt_insn->branch = branch;
133 intel_pt_insn->length = insn->length;
134
135 if (branch == INTEL_PT_BR_CONDITIONAL ||
136 branch == INTEL_PT_BR_UNCONDITIONAL) {
137 #if __BYTE_ORDER == __BIG_ENDIAN
138 switch (insn->immediate.nbytes) {
139 case 1:
140 intel_pt_insn->rel = insn->immediate.value;
141 break;
142 case 2:
143 intel_pt_insn->rel =
144 bswap_16((short)insn->immediate.value);
145 break;
146 case 4:
147 intel_pt_insn->rel = bswap_32(insn->immediate.value);
148 break;
149 default:
150 intel_pt_insn->rel = 0;
151 break;
152 }
153 #else
154 intel_pt_insn->rel = insn->immediate.value;
155 #endif
156 }
157 }
158
intel_pt_get_insn(const unsigned char * buf,size_t len,int x86_64,struct intel_pt_insn * intel_pt_insn)159 int intel_pt_get_insn(const unsigned char *buf, size_t len, int x86_64,
160 struct intel_pt_insn *intel_pt_insn)
161 {
162 struct insn insn;
163
164 insn_init(&insn, buf, len, x86_64);
165 insn_get_length(&insn);
166 if (!insn_complete(&insn) || insn.length > len)
167 return -1;
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);
171 else
172 memcpy(intel_pt_insn->buf, buf, INTEL_PT_INSN_DBG_BUF_SZ);
173 return 0;
174 }
175
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",
187 };
188
intel_pt_insn_name(enum intel_pt_insn_op op)189 const char *intel_pt_insn_name(enum intel_pt_insn_op op)
190 {
191 return branch_name[op];
192 }
193
intel_pt_insn_desc(const struct intel_pt_insn * intel_pt_insn,char * buf,size_t buf_len)194 int intel_pt_insn_desc(const struct intel_pt_insn *intel_pt_insn, char *buf,
195 size_t buf_len)
196 {
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 ? "+" : "",
203 intel_pt_insn->rel);
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));
208 default:
209 break;
210 }
211 return 0;
212 }
213
intel_pt_insn_max_size(void)214 size_t intel_pt_insn_max_size(void)
215 {
216 return MAX_INSN_SIZE;
217 }
218
intel_pt_insn_type(enum intel_pt_insn_op op)219 int intel_pt_insn_type(enum intel_pt_insn_op op)
220 {
221 switch (op) {
222 case INTEL_PT_OP_OTHER:
223 return 0;
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;
246 default:
247 return 0;
248 }
249 }
250