1/* Copyright (c) 2007-2008 The Florida State University
2 * All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions are
6 * met: redistributions of source code must retain the above copyright
7 * notice, this list of conditions and the following disclaimer;
8 * redistributions in binary form must reproduce the above copyright
9 * notice, this list of conditions and the following disclaimer in the
10 * documentation and/or other materials provided with the distribution;
11 * neither the name of the copyright holders nor the names of its
12 * contributors may be used to endorse or promote products derived from
13 * this software without specific prior written permission.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
18 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
19 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
20 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
21 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
25 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 *
27 * Authors: Stephen Hines
28 */
29
30#include "arch/arm/insts/static_inst.hh"
31#include "base/condcodes.hh"
32#include "base/cprintf.hh"
33#include "base/loader/symtab.hh"
34
35namespace ArmISA
36{
37// Shift Rm by an immediate value
38int32_t
39ArmStaticInst::shift_rm_imm(uint32_t base, uint32_t shamt,
40 uint32_t type, uint32_t cfval) const
41{
42 assert(shamt < 32);
43 ArmShiftType shiftType;
44 shiftType = (ArmShiftType)type;
45
46 switch (shiftType)
47 {
48 case LSL:
49 return base << shamt;
50 case LSR:
51 if (shamt == 0)
52 return 0;
53 else
54 return base >> shamt;
55 case ASR:
56 if (shamt == 0)
57 return (int32_t)base >> 31;
58 else
59 return (int32_t)base >> shamt;
60 case ROR:
61 if (shamt == 0)
62 return (cfval << 31) | (base >> 1); // RRX
63 else
64 return (base << (32 - shamt)) | (base >> shamt);
65 default:
65 fprintf(stderr, "Unhandled shift type\n");
66 ccprintf(std::cerr, "Unhandled shift type\n");
67 exit(1);
68 break;
69 }
70 return 0;
71}
72
73// Shift Rm by Rs
74int32_t
75ArmStaticInst::shift_rm_rs(uint32_t base, uint32_t shamt,
76 uint32_t type, uint32_t cfval) const
77{
78 enum ArmShiftType shiftType;
79 shiftType = (enum ArmShiftType) type;
80
81 switch (shiftType)
82 {
83 case LSL:
84 if (shamt >= 32)
85 return 0;
86 else
87 return base << shamt;
88 case LSR:
89 if (shamt >= 32)
90 return 0;
91 else
92 return base >> shamt;
93 case ASR:
94 if (shamt >= 32)
95 return (int32_t)base >> 31;
96 else
97 return (int32_t)base >> shamt;
98 case ROR:
99 shamt = shamt & 0x1f;
100 if (shamt == 0)
101 return base;
102 else
103 return (base << (32 - shamt)) | (base >> shamt);
104 default:
104 fprintf(stderr, "Unhandled shift type\n");
105 ccprintf(std::cerr, "Unhandled shift type\n");
106 exit(1);
107 break;
108 }
109 return 0;
110}
111
112
113// Generate C for a shift by immediate
114bool
115ArmStaticInst::shift_carry_imm(uint32_t base, uint32_t shamt,
116 uint32_t type, uint32_t cfval) const
117{
118 enum ArmShiftType shiftType;
119 shiftType = (enum ArmShiftType) type;
120
121 switch (shiftType)
122 {
123 case LSL:
124 if (shamt == 0)
125 return cfval;
126 else
127 return (base >> (32 - shamt)) & 1;
128 case LSR:
129 if (shamt == 0)
130 return (base >> 31);
131 else
132 return (base >> (shamt - 1)) & 1;
133 case ASR:
134 if (shamt == 0)
135 return (base >> 31);
136 else
137 return (base >> (shamt - 1)) & 1;
138 case ROR:
139 shamt = shamt & 0x1f;
140 if (shamt == 0)
141 return (base & 1); // RRX
142 else
143 return (base >> (shamt - 1)) & 1;
144 default:
144 fprintf(stderr, "Unhandled shift type\n");
145 ccprintf(std::cerr, "Unhandled shift type\n");
146 exit(1);
147 break;
148 }
149 return 0;
150}
151
152
153// Generate C for a shift by Rs
154bool
155ArmStaticInst::shift_carry_rs(uint32_t base, uint32_t shamt,
156 uint32_t type, uint32_t cfval) const
157{
158 enum ArmShiftType shiftType;
159 shiftType = (enum ArmShiftType) type;
160
161 if (shamt == 0)
162 return cfval;
163
164 switch (shiftType)
165 {
166 case LSL:
167 if (shamt > 32)
168 return 0;
169 else
170 return (base >> (32 - shamt)) & 1;
171 case LSR:
172 if (shamt > 32)
173 return 0;
174 else
175 return (base >> (shamt - 1)) & 1;
176 case ASR:
177 if (shamt > 32)
178 shamt = 32;
179 return (base >> (shamt - 1)) & 1;
180 case ROR:
181 shamt = shamt & 0x1f;
182 if (shamt == 0)
183 shamt = 32;
184 return (base >> (shamt - 1)) & 1;
185 default:
185 fprintf(stderr, "Unhandled shift type\n");
186 ccprintf(std::cerr, "Unhandled shift type\n");
187 exit(1);
188 break;
189 }
190 return 0;
191}
192
193
194// Generate the appropriate carry bit for an addition operation
195bool
196ArmStaticInst::arm_add_carry(int32_t result, int32_t lhs, int32_t rhs) const
197{
198 return findCarry(32, result, lhs, rhs);
199}
200
201// Generate the appropriate carry bit for a subtraction operation
202bool
203ArmStaticInst::arm_sub_carry(int32_t result, int32_t lhs, int32_t rhs) const
204{
205 return findCarry(32, result, lhs, ~rhs);
206}
207
208bool
209ArmStaticInst::arm_add_overflow(int32_t result, int32_t lhs, int32_t rhs) const
210{
211 return findOverflow(32, result, lhs, rhs);
212}
213
214bool
215ArmStaticInst::arm_sub_overflow(int32_t result, int32_t lhs, int32_t rhs) const
216{
217 return findOverflow(32, result, lhs, ~rhs);
218}
219
220void
221ArmStaticInst::printReg(std::ostream &os, int reg) const
222{
223 if (reg < FP_Base_DepTag) {
224 switch (reg) {
225 case PCReg:
226 ccprintf(os, "pc");
227 break;
228 case StackPointerReg:
229 ccprintf(os, "sp");
230 break;
231 case FramePointerReg:
232 ccprintf(os, "fp");
233 break;
234 case ReturnAddressReg:
235 ccprintf(os, "lr");
236 break;
237 default:
238 ccprintf(os, "r%d", reg);
239 break;
240 }
241 } else if (reg < Ctrl_Base_DepTag) {
242 ccprintf(os, "f%d", reg - FP_Base_DepTag);
243 } else {
244 reg -= Ctrl_Base_DepTag;
245 assert(reg < NUM_MISCREGS);
246 ccprintf(os, "%s", ArmISA::miscRegName[reg]);
247 }
248}
249
250void
251ArmStaticInst::printMnemonic(std::ostream &os,
252 const std::string &suffix,
253 bool withPred) const
254{
255 os << " " << mnemonic;
256 if (withPred) {
257 unsigned condCode = machInst.condCode;
258 switch (condCode) {
259 case COND_EQ:
260 os << "eq";
261 break;
262 case COND_NE:
263 os << "ne";
264 break;
265 case COND_CS:
266 os << "cs";
267 break;
268 case COND_CC:
269 os << "cc";
270 break;
271 case COND_MI:
272 os << "mi";
273 break;
274 case COND_PL:
275 os << "pl";
276 break;
277 case COND_VS:
278 os << "vs";
279 break;
280 case COND_VC:
281 os << "vc";
282 break;
283 case COND_HI:
284 os << "hi";
285 break;
286 case COND_LS:
287 os << "ls";
288 break;
289 case COND_GE:
290 os << "ge";
291 break;
292 case COND_LT:
293 os << "lt";
294 break;
295 case COND_GT:
296 os << "gt";
297 break;
298 case COND_LE:
299 os << "le";
300 break;
301 case COND_AL:
302 // This one is implicit.
303 break;
304 case COND_NV:
305 os << "nv";
306 break;
307 default:
308 panic("Unrecognized condition code %d.\n", condCode);
309 }
310 os << suffix << " ";
311 }
312}
313
314void
315ArmStaticInst::printMemSymbol(std::ostream &os,
316 const SymbolTable *symtab,
317 const std::string &prefix,
318 const Addr addr,
319 const std::string &suffix) const
320{
321 Addr symbolAddr;
322 std::string symbol;
323 if (symtab && symtab->findNearestSymbol(addr, symbol, symbolAddr)) {
324 ccprintf(os, "%s%s", prefix, symbol);
325 if (symbolAddr != addr)
326 ccprintf(os, "+%d", addr - symbolAddr);
327 ccprintf(os, suffix);
328 }
329}
330
331void
332ArmStaticInst::printShiftOperand(std::ostream &os) const
333{
334 printReg(os, machInst.rm);
335
336 bool immShift = (machInst.opcode4 == 0);
337 bool done = false;
338 unsigned shiftAmt = (machInst.shiftSize);
339 ArmShiftType type = (ArmShiftType)(uint32_t)machInst.shift;
340
341 if ((type == LSR || type == ASR) && immShift && shiftAmt == 0)
342 shiftAmt = 32;
343
344 switch (type) {
345 case LSL:
346 if (immShift && shiftAmt == 0) {
347 done = true;
348 break;
349 }
350 os << ", LSL";
351 break;
352 case LSR:
353 os << ", LSR";
354 break;
355 case ASR:
356 os << ", ASR";
357 break;
358 case ROR:
359 if (immShift && shiftAmt == 0) {
360 os << ", RRX";
361 done = true;
362 break;
363 }
364 os << ", ROR";
365 break;
366 default:
367 panic("Tried to disassemble unrecognized shift type.\n");
368 }
369 if (!done) {
370 os << " ";
371 if (immShift)
372 os << "#" << shiftAmt;
373 else
374 printReg(os, machInst.rs);
375 }
376}
377
378void
379ArmStaticInst::printDataInst(std::ostream &os, bool withImm) const
380{
381 printMnemonic(os, machInst.sField ? "s" : "");
382 //XXX It would be nice if the decoder figured this all out for us.
383 unsigned opcode = machInst.opcode;
384 bool firstOp = true;
385
386 // Destination
387 // Cmp, cmn, teq, and tst don't have one.
388 if (opcode < 8 || opcode > 0xb) {
389 firstOp = false;
390 printReg(os, machInst.rd);
391 }
392
393 // Source 1.
394 // Mov and Movn don't have one of these.
395 if (opcode != 0xd && opcode != 0xf) {
396 if (!firstOp)
397 os << ", ";
398 firstOp = false;
399 printReg(os, machInst.rn);
400 }
401
402 if (!firstOp)
403 os << ", ";
404 if (withImm) {
405 unsigned rotate = machInst.rotate * 2;
406 uint32_t imm = machInst.imm;
407 ccprintf(os, "#%#x", (imm << (32 - rotate)) | (imm >> rotate));
408 } else {
409 printShiftOperand(os);
410 }
411}
412
413std::string
414ArmStaticInst::generateDisassembly(Addr pc,
415 const SymbolTable *symtab) const
416{
417 std::stringstream ss;
418 printMnemonic(ss);
419 return ss.str();
420}
421}