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/faults.hh"
31#include "arch/arm/insts/static_inst.hh"
32#include "base/condcodes.hh"
33#include "base/cprintf.hh"
34#include "base/loader/symtab.hh"
35
36namespace ArmISA
37{
38// Shift Rm by an immediate value
39int32_t
40ArmStaticInst::shift_rm_imm(uint32_t base, uint32_t shamt,
41 uint32_t type, uint32_t cfval) const
42{
43 assert(shamt < 32);
44 ArmShiftType shiftType;
45 shiftType = (ArmShiftType)type;
46
47 switch (shiftType)
48 {
49 case LSL:
50 return base << shamt;
51 case LSR:
52 if (shamt == 0)
53 return 0;
54 else
55 return base >> shamt;
56 case ASR:
57 if (shamt == 0)
58 return (int32_t)base >> 31;
59 else
60 return (int32_t)base >> shamt;
61 case ROR:
62 if (shamt == 0)
63 return (cfval << 31) | (base >> 1); // RRX
64 else
65 return (base << (32 - shamt)) | (base >> shamt);
66 default:
67 ccprintf(std::cerr, "Unhandled shift type\n");
68 exit(1);
69 break;
70 }
71 return 0;
72}
73
74// Shift Rm by Rs
75int32_t
76ArmStaticInst::shift_rm_rs(uint32_t base, uint32_t shamt,
77 uint32_t type, uint32_t cfval) const
78{
79 enum ArmShiftType shiftType;
80 shiftType = (enum ArmShiftType) type;
81
82 switch (shiftType)
83 {
84 case LSL:
85 if (shamt >= 32)
86 return 0;
87 else
88 return base << shamt;
89 case LSR:
90 if (shamt >= 32)
91 return 0;
92 else
93 return base >> shamt;
94 case ASR:
95 if (shamt >= 32)
96 return (int32_t)base >> 31;
97 else
98 return (int32_t)base >> shamt;
99 case ROR:
100 shamt = shamt & 0x1f;
101 if (shamt == 0)
102 return base;
103 else
104 return (base << (32 - shamt)) | (base >> shamt);
105 default:
106 ccprintf(std::cerr, "Unhandled shift type\n");
107 exit(1);
108 break;
109 }
110 return 0;
111}
112
113
114// Generate C for a shift by immediate
115bool
116ArmStaticInst::shift_carry_imm(uint32_t base, uint32_t shamt,
117 uint32_t type, uint32_t cfval) const
118{
119 enum ArmShiftType shiftType;
120 shiftType = (enum ArmShiftType) type;
121
122 switch (shiftType)
123 {
124 case LSL:
125 if (shamt == 0)
126 return cfval;
127 else
128 return (base >> (32 - shamt)) & 1;
129 case LSR:
130 if (shamt == 0)
131 return (base >> 31);
132 else
133 return (base >> (shamt - 1)) & 1;
134 case ASR:
135 if (shamt == 0)
136 return (base >> 31);
137 else
138 return (base >> (shamt - 1)) & 1;
139 case ROR:
140 shamt = shamt & 0x1f;
141 if (shamt == 0)
142 return (base & 1); // RRX
143 else
144 return (base >> (shamt - 1)) & 1;
145 default:
146 ccprintf(std::cerr, "Unhandled shift type\n");
147 exit(1);
148 break;
149 }
150 return 0;
151}
152
153
154// Generate C for a shift by Rs
155bool
156ArmStaticInst::shift_carry_rs(uint32_t base, uint32_t shamt,
157 uint32_t type, uint32_t cfval) const
158{
159 enum ArmShiftType shiftType;
160 shiftType = (enum ArmShiftType) type;
161
162 if (shamt == 0)
163 return cfval;
164
165 switch (shiftType)
166 {
167 case LSL:
168 if (shamt > 32)
169 return 0;
170 else
171 return (base >> (32 - shamt)) & 1;
172 case LSR:
173 if (shamt > 32)
174 return 0;
175 else
176 return (base >> (shamt - 1)) & 1;
177 case ASR:
178 if (shamt > 32)
179 shamt = 32;
180 return (base >> (shamt - 1)) & 1;
181 case ROR:
182 shamt = shamt & 0x1f;
183 if (shamt == 0)
184 shamt = 32;
185 return (base >> (shamt - 1)) & 1;
186 default:
187 ccprintf(std::cerr, "Unhandled shift type\n");
188 exit(1);
189 break;
190 }
191 return 0;
192}
193
194
195// Generate the appropriate carry bit for an addition operation
196bool
197ArmStaticInst::arm_add_carry(int32_t result, int32_t lhs, int32_t rhs) const
198{
199 return findCarry(32, result, lhs, rhs);
200}
201
202// Generate the appropriate carry bit for a subtraction operation
203bool
204ArmStaticInst::arm_sub_carry(int32_t result, int32_t lhs, int32_t rhs) const
205{
206 return findCarry(32, result, lhs, ~rhs);
207}
208
209bool
210ArmStaticInst::arm_add_overflow(int32_t result, int32_t lhs, int32_t rhs) const
211{
212 return findOverflow(32, result, lhs, rhs);
213}
214
215bool
216ArmStaticInst::arm_sub_overflow(int32_t result, int32_t lhs, int32_t rhs) const
217{
218 return findOverflow(32, result, lhs, ~rhs);
219}
220
221void
222ArmStaticInst::printReg(std::ostream &os, int reg) const
223{
224 if (reg < FP_Base_DepTag) {
225 switch (reg) {
226 case PCReg:
227 ccprintf(os, "pc");
228 break;
229 case StackPointerReg:
230 ccprintf(os, "sp");
231 break;
232 case FramePointerReg:
233 ccprintf(os, "fp");
234 break;
235 case ReturnAddressReg:
236 ccprintf(os, "lr");
237 break;
238 default:
239 ccprintf(os, "r%d", reg);
240 break;
241 }
242 } else if (reg < Ctrl_Base_DepTag) {
243 ccprintf(os, "f%d", reg - FP_Base_DepTag);
244 } else {
245 reg -= Ctrl_Base_DepTag;
246 assert(reg < NUM_MISCREGS);
247 ccprintf(os, "%s", ArmISA::miscRegName[reg]);
248 }
249}
250
251void
252ArmStaticInst::printMnemonic(std::ostream &os,
253 const std::string &suffix,
254 bool withPred) const
255{
256 os << " " << mnemonic;
257 if (withPred) {
258 unsigned condCode = machInst.condCode;
259 switch (condCode) {
260 case COND_EQ:
261 os << "eq";
262 break;
263 case COND_NE:
264 os << "ne";
265 break;
266 case COND_CS:
267 os << "cs";
268 break;
269 case COND_CC:
270 os << "cc";
271 break;
272 case COND_MI:
273 os << "mi";
274 break;
275 case COND_PL:
276 os << "pl";
277 break;
278 case COND_VS:
279 os << "vs";
280 break;
281 case COND_VC:
282 os << "vc";
283 break;
284 case COND_HI:
285 os << "hi";
286 break;
287 case COND_LS:
288 os << "ls";
289 break;
290 case COND_GE:
291 os << "ge";
292 break;
293 case COND_LT:
294 os << "lt";
295 break;
296 case COND_GT:
297 os << "gt";
298 break;
299 case COND_LE:
300 os << "le";
301 break;
302 case COND_AL:
303 // This one is implicit.
304 break;
305 case COND_NV:
306 os << "nv";
307 break;
308 default:
309 panic("Unrecognized condition code %d.\n", condCode);
310 }
311 os << suffix << " ";
312 }
313}
314
315void
316ArmStaticInst::printMemSymbol(std::ostream &os,
317 const SymbolTable *symtab,
318 const std::string &prefix,
319 const Addr addr,
320 const std::string &suffix) const
321{
322 Addr symbolAddr;
323 std::string symbol;
324 if (symtab && symtab->findNearestSymbol(addr, symbol, symbolAddr)) {
325 ccprintf(os, "%s%s", prefix, symbol);
326 if (symbolAddr != addr)
327 ccprintf(os, "+%d", addr - symbolAddr);
328 ccprintf(os, suffix);
329 }
330}
331
332void
333ArmStaticInst::printShiftOperand(std::ostream &os) const
334{
335 printReg(os, machInst.rm);
336
337 bool immShift = (machInst.opcode4 == 0);
338 bool done = false;
339 unsigned shiftAmt = (machInst.shiftSize);
340 ArmShiftType type = (ArmShiftType)(uint32_t)machInst.shift;
341
342 if ((type == LSR || type == ASR) && immShift && shiftAmt == 0)
343 shiftAmt = 32;
344
345 switch (type) {
346 case LSL:
347 if (immShift && shiftAmt == 0) {
348 done = true;
349 break;
350 }
351 os << ", LSL";
352 break;
353 case LSR:
354 os << ", LSR";
355 break;
356 case ASR:
357 os << ", ASR";
358 break;
359 case ROR:
360 if (immShift && shiftAmt == 0) {
361 os << ", RRX";
362 done = true;
363 break;
364 }
365 os << ", ROR";
366 break;
367 default:
368 panic("Tried to disassemble unrecognized shift type.\n");
369 }
370 if (!done) {
371 os << " ";
372 if (immShift)
373 os << "#" << shiftAmt;
374 else
375 printReg(os, machInst.rs);
376 }
377}
378
379void
380ArmStaticInst::printDataInst(std::ostream &os, bool withImm) const
381{
382 printMnemonic(os, machInst.sField ? "s" : "");
383 //XXX It would be nice if the decoder figured this all out for us.
384 unsigned opcode = machInst.opcode;
385 bool firstOp = true;
386
387 // Destination
388 // Cmp, cmn, teq, and tst don't have one.
389 if (opcode < 8 || opcode > 0xb) {
390 firstOp = false;
391 printReg(os, machInst.rd);
392 }
393
394 // Source 1.
395 // Mov and Movn don't have one of these.
396 if (opcode != 0xd && opcode != 0xf) {
397 if (!firstOp)
398 os << ", ";
399 firstOp = false;
400 printReg(os, machInst.rn);
401 }
402
403 if (!firstOp)
404 os << ", ";
405 if (withImm) {
406 unsigned rotate = machInst.rotate * 2;
407 uint32_t imm = machInst.imm;
408 ccprintf(os, "#%#x", (imm << (32 - rotate)) | (imm >> rotate));
409 } else {
410 printShiftOperand(os);
411 }
412}
413
414std::string
415ArmStaticInst::generateDisassembly(Addr pc,
416 const SymbolTable *symtab) const
417{
418 std::stringstream ss;
419 printMnemonic(ss);
420 return ss.str();
421}
422}