1 /*
2 * Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved.
3 * Copyright (c) 2019 SAP SE. All rights reserved.
4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5 *
6 * This code is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 only, as
8 * published by the Free Software Foundation.
9 *
10 * This code is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
13 * version 2 for more details (a copy is included in the LICENSE file that
14 * accompanied this code).
15 *
16 * You should have received a copy of the GNU General Public License version
17 * 2 along with this work; if not, write to the Free Software Foundation,
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
19 *
20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
21 * or visit www.oracle.com if you need additional information or have any
22 * questions.
23 *
24 */
25
26 // AbstractDisassembler is the base class for
27 // platform-specific Disassembler classes.
28
29 #include "precompiled.hpp"
30 #include "asm/assembler.inline.hpp"
31 #include "compiler/abstractDisassembler.hpp"
32 #include "oops/oop.inline.hpp"
33 #include "utilities/debug.hpp"
34 #include "utilities/ostream.hpp"
35
36 // Default values for what is being printed as line prefix when disassembling a single instruction.
37 // Can be overridden by command line parameter PrintAssemblyOptions.
38 bool AbstractDisassembler::_show_data_hex = true;
39 bool AbstractDisassembler::_show_data_int = false;
40 bool AbstractDisassembler::_show_data_float = false;
41 bool AbstractDisassembler::_align_instr = false;
42 bool AbstractDisassembler::_show_pc = true;
43 bool AbstractDisassembler::_show_offset = false;
44 bool AbstractDisassembler::_show_structs = false;
45 bool AbstractDisassembler::_show_comment = false;
46 bool AbstractDisassembler::_show_block_comment = false;
47
48 // set "true" to see what's in memory bit by bit
49 // might prove cumbersome on platforms where instr_len is hard to find out
50 bool AbstractDisassembler::_show_bytes = false;
51
52 // Return #bytes printed. Callers may use that for output alignment.
53 // Print instruction address, and offset from blob begin.
54 // Offset width (2, 4, 6, 8 bytes) is adapted to size of blob.
55 // Working assumption: we are at st->bol() upon entry. If not, it's the
56 // caller's responsibility to guarantee proper alignment.
57 int AbstractDisassembler::print_location(address here, address begin, address end, outputStream* st, bool align, bool print_header) {
58 const int pos_0 = st->position();
59
60 if (show_pc() || show_offset()) {
61 st->print(" ");
62 }
63
64 if (show_pc()) {
65 if (print_header) {
66 st->print(" %*s", 18, "Address");
67 } else {
68 st->print(" " PTR_FORMAT, p2i(here));
69 }
70 }
71
72 if (show_offset()) {
73 #ifdef ASSERT
74 if ((uintptr_t)begin > (uintptr_t)here) st->print(">>begin(" PTR_FORMAT ") > here(" PTR_FORMAT ")<<", p2i(begin), p2i(here));
75 if ((uintptr_t)end < (uintptr_t)here) st->print(">> end(" PTR_FORMAT ") < here(" PTR_FORMAT ")<<", p2i(end), p2i(here));
76 assert((uintptr_t)begin <= (uintptr_t)end, "inverted address range");
77 #endif
78 const int blob_len = end - begin;
79 const int offset = here - begin;
80 const int width = (blob_len < (1<< 8)) ? 2 : (blob_len < (1<<16)) ? 4 : (blob_len < (1<<24)) ? 6 : 8;
81 if (print_header) {
82 st->print(" %*s", width+5, "offset");
83 } else {
84 st->print(" (+0x%*.*x)", width, width, offset);
85 }
86 }
87
88 if ((show_pc() || show_offset()) && !print_header) {
89 st->print(": ");
90 }
91
92 if (align) {
93 const uint tabspacing = 8;
94 const uint pos = st->position();
95 const uint aligned_pos = ((pos+tabspacing-1)/tabspacing)*tabspacing /* - 1 */;
96 st->fill_to(aligned_pos);
97 }
98
99 return st->position() - pos_0;
100 }
101
102
103 // Return #bytes printed. Callers may use that for output alignment.
104 // Print instruction in hexadecimal representation, using 2-byte blocks.
105 // Used with real disassemblies. Not so useful with abstract disassemblies.
106 int AbstractDisassembler::print_instruction(address here, int len, int max_len, outputStream* st, bool align, bool print_header) {
107 if (show_bytes()) {
108 const int block_bytes = 2;
109 const int pos_0 = st->position();
110 address pos = here;
111
112 //---< print instruction bytes in blocks >---
113 // must print byte by byte: address might be unaligned.
114 for (; pos <= here + len - block_bytes; pos += block_bytes) {
115 for (address byte = pos; byte < pos + block_bytes; byte++) {
116 st->print("%2.2x", *byte);
117 }
118 st->print(" ");
119 }
120
121 //---< Print the remaining bytes of the instruction >---
122 if ((len & (block_bytes - 1)) != 0) {
123 for (; pos < here + len; pos++) {
124 st->print("%2.2x", *pos);
125 }
126 }
127
128 //---< filler for shorter than max_len instructions >---
129 for (int i = len+1; i < max_len; i++) {
130 st->print(" ");
131 }
132
133 st->print(" "); // separator space.
134 print_delimiter(st);
135 return st->position() - pos_0;
136 }
137
138 if (align) {
139 const uint tabspacing = 8;
140 const uint pos = st->position();
141 const uint aligned_pos = ((pos+tabspacing-1)/tabspacing)*tabspacing /* - 1 */;
142 st->fill_to(aligned_pos);
143 }
144
145 return 0;
146 }
147
148
149 // Return #bytes printed. Callers may use that for output alignment.
150 // Print data (e.g. constant pool entries) in hex format.
151 // Depending on the alignment, short, int, and long entities are printed.
152 // If selected, data is formatted as int/long and float/double values in addition.
153 int AbstractDisassembler::print_hexdata(address here, int len, outputStream* st, bool print_header) {
154 const int tsize = 8;
155 const int pos_0 = st->position();
156 int pos = pos_0;
157 int align = ((pos+tsize-1)/tsize)*tsize;
158 st->fill_to(align);
159
160 //---< printing hex data >---
161 if (show_data_hex()) {
162 switch (len) {
163 case 1: if (print_header) {
164 st->print("hex1");
165 } else {
166 st->print("0x%02x", *here);
167 }
168 st->fill_to(align += tsize);
169 case 2: if (print_header) {
170 st->print(" hex2");
171 } else {
172 if (((uintptr_t)(here)&0x01) == 0) {
173 st->print("0x%04x", *((jushort*)here));
174 }
175 }
176 st->fill_to(align += tsize);
177 case 4: if (print_header) {
178 st->print(" hex4");
179 } else {
180 if (((uintptr_t)(here)&0x03) == 0) {
181 st->print("0x%08x", *((juint*)here));
182 }
183 }
184 st->fill_to(align += 2*tsize);
185 case 8: if (print_header) {
186 st->print(" hex8");
187 } else {
188 if (((uintptr_t)(here)&0x07) == 0) {
189 st->print(PTR_FORMAT, *((uintptr_t*)here));
190 }
191 }
192 st->fill_to(align += 3*tsize);
193 break;
194 default: ;
195 }
196 pos = st->position();
197 align = ((pos+tsize-1)/tsize)*tsize;
198 st->fill_to(align);
199 }
200
201 //---< printing int/long data >---
202 if (show_data_int()) {
203 switch (len) {
204 case 4: if (print_header) {
205 st->print(" int");
206 } else {
207 if (((uintptr_t)(here)&0x03) == 0) {
208 st->print("%12.1d", *((jint*)here));
209 }
210 }
211 st->fill_to(align += 2*tsize);
212 case 8: if (print_header) {
213 st->print(" long");
214 } else {
215 if (((uintptr_t)(here)&0x07) == 0) {
216 st->print(JLONG_FORMAT_W(23), *((jlong*)here));
217 }
218 }
219 st->fill_to(align += 3*tsize);
220 break;
221 default: ;
222 }
223 pos = st->position();
224 align = ((pos+tsize-1)/tsize)*tsize;
225 st->fill_to(align);
226 }
227
228 //---< printing float/double data >---
229 if (show_data_float()) {
230 switch (len) {
231 case 4: if (print_header) {
232 st->print(" float");
233 } else {
234 if (((uintptr_t)(here)&0x03) == 0) {
235 st->print("%15.7e", (double)*((float*)here));
236 }
237 }
238 st->fill_to(align += 2*tsize);
239 case 8: if (print_header) {
240 st->print(" double");
241 } else {
242 if (((uintptr_t)(here)&0x07) == 0) {
243 st->print("%23.15e", *((double*)here));
244 }
245 }
246 st->fill_to(align += 3*tsize);
247 break;
248 default: ;
249 }
250 }
251
252 return st->position() - pos_0;
253 }
254
255
256 // Return #bytes printed. Callers may use that for output alignment.
257 // Print an instruction delimiter.
258 int AbstractDisassembler::print_delimiter(outputStream* st) {
259 if (align_instr()) { st->print("| "); return 2; }
260 else return 0;
261 }
262
263
264 // Decodes the one instruction at address start in a platform-independent format.
265 // Returns the start of the next instruction (which is 'start' plus 'instruction_size_in_bytes').
266 // The parameter max_instr_size_in_bytes is used for output alignment purposes only.
267 address AbstractDisassembler::decode_instruction_abstract(address start,
268 outputStream* st,
269 const int instruction_size_in_bytes,
270 const int max_instr_size_in_bytes) {
271 assert(instruction_size_in_bytes > 0, "no zero-size instructions!");
272 assert(max_instr_size_in_bytes >= instruction_size_in_bytes, "inconsistent call parameters");
273
274 //---< current instruction is at the start address >---
275 unsigned char* current = (unsigned char*) start;
276 int filler_limit = align_instr() ? max_instr_size_in_bytes : ((instruction_size_in_bytes+abstract_instruction_bytes_per_block-1)/abstract_instruction_bytes_per_block)
277 *abstract_instruction_bytes_per_block;
278
279 //---< print the instruction's bytes >---
280 for (int i = 1; i <= instruction_size_in_bytes; i++) {
281 st->print("%02x", *current);
282 ++current;
283 if (abstract_instruction_bytes_per_block <= max_instr_size_in_bytes) {
284 if (i%abstract_instruction_bytes_per_block == 0) st->print(" ");
285 } else {
286 if (i == instruction_size_in_bytes) st->print(" ");
287 }
288 }
289
290 //---< print some filler spaces to column-align instructions >---
291 for (int i = instruction_size_in_bytes+1; i <= filler_limit; i++) {
292 st->print(" ");
293 if (abstract_instruction_bytes_per_block <= max_instr_size_in_bytes) {
294 if (i%abstract_instruction_bytes_per_block == 0) st->print(" ");
295 } else {
296 if (i == instruction_size_in_bytes) st->print(" ");
297 }
298 }
299
300 //---< the address of the next instruction >---
301 return (address) current;
302 }
303
304
305 // Decodes all instructions in the given range [start..end)
306 // calling decode_instruction_abstract for each instruction.
307 // The format is platform dependent only to the extend that
308 // it respects the actual instruction length where possible.
309 // Does not print any markers or decorators.
310 void AbstractDisassembler::decode_range_abstract(address range_start, address range_end,
311 address start, address end,
312 outputStream* st,
313 const int max_instr_size_in_bytes) {
314 assert(st != NULL, "need an output stream (no default)!");
315 int idx = 0;
316 address pos = range_start;
317
318 while ((pos != NULL) && (pos < range_end)) {
319 int instr_size_in_bytes = Assembler::instr_len(pos);
320
321 if (idx == 0) print_location(pos, start, end, st, false, false);
322 else print_delimiter(st);
323
324 //---< print the instruction's bytes >---
325 // don't access storage beyond end of range
326 if (pos + instr_size_in_bytes <= range_end) {
327 pos = decode_instruction_abstract(pos, st, instr_size_in_bytes, max_instr_size_in_bytes);
328 } else {
329 // If the range to be decoded contains garbage at the end (e.g. 0xcc initializer bytes),
330 // instruction size calculation may run out of sync. Just terminate in that case.
331 pos = range_end;
332 }
333
334 idx += instr_size_in_bytes;
335 if (start_newline(idx)) {
336 st->cr();
337 idx = 0;
338 }
339 }
340 }
341
342
343 // Decodes all instructions in the given range [start..end).
344 // The output is enclosed in [MachCode] and [/MachCode] tags for later recognition.
345 // The format is platform dependent only to the extend that
346 // it respects the actual instruction length where possible.
347 void AbstractDisassembler::decode_abstract(address start, address end, outputStream* ost,
348 const int max_instr_size_in_bytes) {
349 int idx = 0;
350 address pos = start;
351
352 outputStream* st = (ost == NULL) ? tty : ost;
353
354 //---< Open the output (Marker for post-mortem disassembler) >---
355 st->bol();
356 st->print_cr("[MachCode]");
357
358 decode_range_abstract(start, end, start, end, st, max_instr_size_in_bytes);
359
360 //---< Close the output (Marker for post-mortem disassembler) >---
361 st->bol();
362 st->print_cr("[/MachCode]");
363 }