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 #if defined(ARM) || defined(AARCH64)
48 bool AbstractDisassembler::_show_bytes = false; // set "true" to see what's in memory bit by bit
49 // might prove cumbersome because instr_len is hard to find on arm
50 #endif
51 #if defined(PPC)
52 bool AbstractDisassembler::_show_bytes = false; // set "true" to see what's in memory bit by bit
53 #endif
54 #if defined(S390)
55 bool AbstractDisassembler::_show_bytes = false; // set "true" to see what's in memory bit by bit
56 #endif
57 #if defined(SPARC)
58 bool AbstractDisassembler::_show_bytes = false; // set "true" to see what's in memory bit by bit
59 #endif
60 #if defined(X86)
61 bool AbstractDisassembler::_show_bytes = false; // set "true" to see what's in memory bit by bit
62 // might prove cumbersome because instr_len is hard to find on x86
63 #endif
64
65 // Return #bytes printed. Callers may use that for output alignment.
66 // Print instruction address, and offset from blob begin.
67 // Offset width (2, 4, 6, 8 bytes) is adapted to size of blob.
68 // Working assumption: we are at st->bol() upon entry. If not, it's the
69 // caller's responsibility to guarantee proper alignment.
70 int AbstractDisassembler::print_location(address here, address begin, address end, outputStream* st, bool align, bool print_header) {
71 const int pos_0 = st->position();
72
73 if (show_pc() || show_offset()) {
74 st->print(" ");
75 }
76
77 if (show_pc()) {
78 if (print_header) {
79 st->print(" %*s", 18, "Address");
80 } else {
81 st->print(" " PTR_FORMAT, p2i(here));
82 }
83 }
84
85 if (show_offset()) {
86 #ifdef ASSERT
87 if ((uintptr_t)begin > (uintptr_t)here) st->print(">>begin(" PTR_FORMAT ") > here(" PTR_FORMAT ")<<", p2i(begin), p2i(here));
88 if ((uintptr_t)end < (uintptr_t)here) st->print(">> end(" PTR_FORMAT ") < here(" PTR_FORMAT ")<<", p2i(end), p2i(here));
89 assert((uintptr_t)begin <= (uintptr_t)end, "inverted address range");
90 #endif
91 const int blob_len = end - begin;
92 const int offset = here - begin;
93 const int width = (blob_len < (1<< 8)) ? 2 : (blob_len < (1<<16)) ? 4 : (blob_len < (1<<24)) ? 6 : 8;
94 if (print_header) {
95 st->print(" %*s", width+5, "offset");
96 } else {
97 st->print(" (+0x%*.*x)", width, width, offset);
98 }
99 }
100
101 if ((show_pc() || show_offset()) && !print_header) {
102 st->print(": ");
103 }
104
105 if (align) {
106 const uint tabspacing = 8;
107 const uint pos = st->position();
108 const uint aligned_pos = ((pos+tabspacing-1)/tabspacing)*tabspacing /* - 1 */;
109 st->fill_to(aligned_pos);
110 }
111
112 return st->position() - pos_0;
113 }
114
115
116 // Return #bytes printed. Callers may use that for output alignment.
117 // Print instruction in hexadecimal representation, using 2-byte blocks.
118 // Used with real disassemblies. Not so useful with abstract disassemblies.
119 int AbstractDisassembler::print_instruction(address here, int len, int max_len, outputStream* st, bool align, bool print_header) {
120 if (show_bytes()) {
121 const int block_bytes = 2;
122 const int pos_0 = st->position();
123 address pos = here;
124
125 //---< print instruction bytes in blocks >---
126 // must print byte by byte: address might be unaligned.
127 for (; pos <= here + len - block_bytes; pos += block_bytes) {
128 for (address byte = pos; byte < pos + block_bytes; byte++) {
129 st->print("%2.2x", *byte);
130 }
131 st->print(" ");
132 }
133
134 //---< Print the remaining bytes of the instruction >---
135 if ((len & (block_bytes - 1)) != 0) {
136 for (; pos < here + len; pos++) {
137 st->print("%2.2x", *pos);
138 }
139 }
140
141 //---< filler for shorter than max_len instructions >---
142 for (int i = len+1; i < max_len; i++) {
143 st->print(" ");
144 }
145
146 st->print(" "); // separator space.
147 print_delimiter(st);
148 return st->position() - pos_0;
149 }
150
151 if (align) {
152 const uint tabspacing = 8;
153 const uint pos = st->position();
154 const uint aligned_pos = ((pos+tabspacing-1)/tabspacing)*tabspacing /* - 1 */;
155 st->fill_to(aligned_pos);
156 }
157
158 return 0;
159 }
160
161
162 // Return #bytes printed. Callers may use that for output alignment.
163 // Print data (e.g. constant pool entries) in hex format.
164 // Depending on the alignment, short, int, and long entities are printed.
165 // If selected, data is formatted as int/long and float/double values in addition.
166 int AbstractDisassembler::print_hexdata(address here, int len, outputStream* st, bool print_header) {
167 const int tsize = 8;
168 const int pos_0 = st->position();
169 int pos = pos_0;
170 int align = ((pos+tsize-1)/tsize)*tsize;
171 st->fill_to(align);
172
173 //---< printing hex data >---
174 if (show_data_hex()) {
175 switch (len) {
176 case 1: if (print_header) {
177 st->print("hex1");
178 } else {
179 st->print("0x%02x", *here);
180 }
181 st->fill_to(align += tsize);
182 case 2: if (print_header) {
183 st->print(" hex2");
184 } else {
185 if (((uintptr_t)(here)&0x01) == 0) {
186 st->print("0x%04x", *((jushort*)here));
187 }
188 }
189 st->fill_to(align += tsize);
190 case 4: if (print_header) {
191 st->print(" hex4");
192 } else {
193 if (((uintptr_t)(here)&0x03) == 0) {
194 st->print("0x%08x", *((juint*)here));
195 }
196 }
197 st->fill_to(align += 2*tsize);
198 case 8: if (print_header) {
199 st->print(" hex8");
200 } else {
201 if (((uintptr_t)(here)&0x07) == 0) {
202 st->print(PTR64_FORMAT, *((uintptr_t*)here));
203 }
204 }
205 st->fill_to(align += 3*tsize);
206 break;
207 default: ;
208 }
209 pos = st->position();
210 align = ((pos+tsize-1)/tsize)*tsize;
211 st->fill_to(align);
212 }
213
214 //---< printing int/long data >---
215 if (show_data_int()) {
216 switch (len) {
217 case 4: if (print_header) {
218 st->print(" int");
219 } else {
220 if (((uintptr_t)(here)&0x03) == 0) {
221 st->print("%12.1d", *((jint*)here));
222 }
223 }
224 st->fill_to(align += 2*tsize);
225 case 8: if (print_header) {
226 st->print(" long");
227 } else {
228 if (((uintptr_t)(here)&0x07) == 0) {
229 st->print("%23.1ld", *((jlong*)here));
230 }
231 }
232 st->fill_to(align += 3*tsize);
233 break;
234 default: ;
235 }
236 pos = st->position();
237 align = ((pos+tsize-1)/tsize)*tsize;
238 st->fill_to(align);
239 }
240
241 //---< printing float/double data >---
242 if (show_data_float()) {
243 switch (len) {
244 case 4: if (print_header) {
245 st->print(" float");
246 } else {
247 if (((uintptr_t)(here)&0x03) == 0) {
248 st->print("%15.7e", (double)*((float*)here));
249 }
250 }
251 st->fill_to(align += 2*tsize);
252 case 8: if (print_header) {
253 st->print(" double");
254 } else {
255 if (((uintptr_t)(here)&0x07) == 0) {
256 st->print("%23.15e", *((double*)here));
257 }
258 }
259 st->fill_to(align += 3*tsize);
260 break;
261 default: ;
262 }
263 }
264
265 return st->position() - pos_0;
266 }
267
268
269 // Return #bytes printed. Callers may use that for output alignment.
270 // Print an instruction delimiter.
271 int AbstractDisassembler::print_delimiter(outputStream* st) {
272 if (align_instr()) { st->print("| "); return 2; }
273 else return 0;
274 }
275
276
277 // Decodes the one instruction at address start in a platform-independent format.
278 // Returns the start of the next instruction (which is 'start' plus 'instruction_size_in_bytes').
279 // The parameter max_instr_size_in_bytes is used for output alignment purposes only.
280 address AbstractDisassembler::decode_instruction_abstract(address start,
281 outputStream* st,
282 const int instruction_size_in_bytes,
283 const int max_instr_size_in_bytes) {
284 assert(instruction_size_in_bytes > 0, "no zero-size instructions!");
285 assert(max_instr_size_in_bytes >= instruction_size_in_bytes, "inconsistent call parameters");
286
287 //---< current instruction is at the start address >---
288 unsigned char* current = (unsigned char*) start;
289 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)
290 *abstract_instruction_bytes_per_block;
291
292 //---< print the instruction's bytes >---
293 for (int i = 1; i <= instruction_size_in_bytes; i++) {
294 st->print("%02x", *current);
295 ++current;
296 if (abstract_instruction_bytes_per_block <= max_instr_size_in_bytes) {
297 if (i%abstract_instruction_bytes_per_block == 0) st->print(" ");
298 } else {
299 if (i == instruction_size_in_bytes) st->print(" ");
300 }
301 }
302
303 //---< print some filler spaces to column-align instructions >---
304 for (int i = instruction_size_in_bytes+1; i <= filler_limit; i++) {
305 st->print(" ");
306 if (abstract_instruction_bytes_per_block <= max_instr_size_in_bytes) {
307 if (i%abstract_instruction_bytes_per_block == 0) st->print(" ");
308 } else {
309 if (i == instruction_size_in_bytes) st->print(" ");
310 }
311 }
312
313 //---< the address of the next instruction >---
314 return (address) current;
315 }
316
317
318 // Decodes all instructions in the given range [start..end)
319 // calling decode_instruction_abstract for each instruction.
320 // The format is platform dependent only to the extend that
321 // it respects the actual instruction length where possible.
322 // Does not print any markers or decorators.
323 void AbstractDisassembler::decode_range_abstract(address range_start, address range_end,
324 address start, address end,
325 outputStream* st,
326 const int max_instr_size_in_bytes) {
327 assert(st != NULL, "need an output stream (no default)!");
328 int idx = 0;
329 address pos = range_start;
330
331 while ((pos != NULL) && (pos < range_end)) {
332 int instr_size_in_bytes = Assembler::instr_len(pos);
333
334 if (idx == 0) print_location(pos, start, end, st, false, false);
335 else print_delimiter(st);
336
337 //---< print the instruction's bytes >---
338 // don't access storage beyond end of range
339 if (pos + instr_size_in_bytes <= range_end) {
340 pos = decode_instruction_abstract(pos, st, instr_size_in_bytes, max_instr_size_in_bytes);
341 } else {
342 // If the range to be decoded contains garbage at the end (e.g. 0xcc initializer bytes),
343 // instruction size calculation may run out of sync. Just terminate in that case.
344 pos = range_end;
345 }
346
347 idx += instr_size_in_bytes;
348 if (start_newline(idx)) {
349 st->cr();
350 idx = 0;
351 }
352 }
353 }
354
355
356 // Decodes all instructions in the given range [start..end).
357 // The output is enclosed in [MachCode] and [/MachCode] tags for later recognition.
358 // The format is platform dependent only to the extend that
359 // it respects the actual instruction length where possible.
360 void AbstractDisassembler::decode_abstract(address start, address end, outputStream* ost,
361 const int max_instr_size_in_bytes) {
362 int idx = 0;
363 address pos = start;
364
365 outputStream* st = (ost == NULL) ? tty : ost;
366
367 //---< Open the output (Marker for post-mortem disassembler) >---
368 st->bol();
369 st->print_cr("[MachCode]");
370
371 decode_range_abstract(start, end, start, end, st, max_instr_size_in_bytes);
372
373 //---< Close the output (Marker for post-mortem disassembler) >---
374 st->bol();
375 st->print_cr("[/MachCode]");
376 }