source: liacs/coco/assignment4/CodeGenerator.cc@ 385

Last change on this file since 385 was 2, checked in by Rick van der Zwet, 15 years ago

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[2]1/*
2 * CodeGenerator.cc - Implementation of the CodeGenerator class
3 *
4 * Part of the assignment of the Compiler Construction course
5 * LIACS, Leiden University
6 */
7
8#include "IStatement.h"
9#include "AssemblerCode.h"
10#include "MStatement.h"
11
12
13#include "CodeGenerator.h"
14#include "globals.h"
15#include <time.h>
16#include <unistd.h>
17#include <cassert>
18
19using namespace std;
20
21bool IsGlobal(Symbol * sym); // Is the specified symbol a global variable?
22
23#define SP_ALTER(offset) fprintf(out, "\taddi\t$sp, $sp, %d\n", offset)
24#define OP1_NAME_C_STR(stmt) stmt->GetOperand1()->GetSymbol()->GetName().c_str()
25#define OP1_NAME_STR(stmt) string(SYMBOL_PREFIX) + stmt->GetOperand1()->GetSymbol()->GetName()
26#define OP2_NAME_C_STR(stmt) stmt->GetOperand2()->GetSymbol()->GetName().c_str()
27#define RESULT_NAME_C_STR(stmt) stmt->GetResult()->GetSymbol()->GetName().c_str()
28
29
30// Constructor
31
32CodeGenerator::CodeGenerator()
33: mCode(), currentFrame(mCode), rManager(currentFrame, mCode) {
34}
35
36
37// Destructor
38
39CodeGenerator::~CodeGenerator() {
40}
41
42
43// Generates a header
44
45void CodeGenerator::GenerateHeader(FILE * out) {
46 time_t rawtime;
47 struct tm * timeinfo;
48
49 time(&rawtime);
50 timeinfo = localtime(&rawtime);
51 char hostname[20];
52 gethostname(hostname, 20);
53
54 fprintf(out, "## Output generated by ./comp @ %s\n", hostname);
55 fprintf(out, "## %s\n", asctime(timeinfo));
56 fprintf(out, "## Compiler Construction Course - Leiden University - LIACS\n");
57 fprintf(out, "## Johan IJsveld - Rick van der Zwet\n");
58 fprintf(out, "## BSD Licenced\n");
59
60}
61
62
63// Generates the declarations for the global variables
64
65void CodeGenerator::GenerateGlobalDecls(FILE *, SymbolTable * symtab) {
66 Scope * globalScope;
67 Symbol * sym;
68
69 mCode.AppendStatement(new MStatement(MOP_DATA, "Global data section"));
70 mCode.AppendStatement(new MStatement(MOP_ALIGN, new MOperand(MT_INT, 4)));
71
72 globalScope = symtab->GetRootScope();
73
74 // Here we iterate over all global variables in the symbol table and
75 // generate a declaration.
76 for (unsigned int i = 0; i < globalScope->GetNumberOfSymbols(); i++) {
77 sym = globalScope->GetSymbol(i);
78 if (IsGlobal(sym)) {
79 MStatement *stmt = new MStatement(MOP_LABEL);
80 stmt->SetLabel(string(SYMBOL_PREFIX) + sym->GetName());
81 mCode.AppendStatement(stmt);
82 if (sym->GetReturnType() == RT_INT) {
83 mCode.AppendStatement(new MStatement(MOP_WORD, new MOperand(MT_INT, 0)));
84 } else {
85 mCode.AppendStatement(new MStatement(MOP_FLOAT, new MOperand(MT_REAL, 0.0f)));
86 }
87 }
88 }
89
90}
91
92
93// Takes an IntermediateCode object and emits MIPS assembly instructions
94
95void CodeGenerator::GenerateCode(FILE *out, SymbolTable * symtab, IntermediateCode * inputCode) {
96 IStatement * stmt;
97
98 // Generate a general 'stub'.
99 mCode.AppendStatement(new MStatement(MOP_TEXT, "Code section"));
100 mCode.AppendStatement(new MStatement(MOP_ALIGN, new MOperand(MT_INT, 4)));
101 mCode.AppendStatement(new MStatement(MOP_GLOBL, new MOperand(MT_LABEL, "main")));
102 mCode.AppendStatement(new MStatement(MOP_ENT, new MOperand(MT_LABEL, "main")));
103 MStatement *mstmt = new MStatement(MOP_LABEL);
104 mstmt->SetLabel("main");
105 mCode.AppendStatement(mstmt);
106 mCode.AppendStatement(StackPointerChange(-4));
107 mCode.AppendStatement(new MStatement(MOP_JAL, new MOperand(MT_LABEL, string(SYMBOL_PREFIX) + inputCode->GetProgramName()), "Jump to program body"));
108 mCode.AppendStatement(StackPointerChange(4));
109 mCode.AppendStatement(new MStatement(MOP_ADDI, new MOperand(MT_REGISTER, R_V0), new MOperand(MT_REGISTER, R_ZERO), new MOperand(MT_INT, 10), "Exit system call"));
110 mCode.AppendStatement(new MStatement(MOP_SYSCALL));
111 mCode.AppendStatement(new MStatement(MOP_END, new MOperand(MT_LABEL, "main")));
112
113 // Here we step through the intermediate code and output assembly instructions
114 for (unsigned int i = 0; i < inputCode->GetStatementCount(); i++) {
115 stmt = inputCode->GetStatement(i);
116
117 switch (stmt->GetOperator()) {
118 /* Subprogram entry
119 operand1 should refer to the corresponding Symbol_Subprogram object */
120 case IOP_SUBPROG: // [1--] Subprogram
121 {
122 // The start of a subprogram: analyze it, and generate the prologue.
123 currentFrame.AnalyzeSubprogram(symtab, stmt->GetOperand1()->GetSymbol());
124 currentFrame.GeneratePrologue(out);
125 break;
126 }
127 /* Subprogram return
128 operand1 should contain the value that has to be returned */
129 case IOP_RETURN: // [---] Procedure return
130 {
131 // The end of a subprogram:
132 // write back all registers
133 rManager.SpillAll();
134
135 // generate the epilogue
136 currentFrame.GenerateEpilogue(out);
137 break;
138 }
139 case IOP_RETURN_I: // [1--] Integer function return
140 {
141 // The end of a subprogram:
142 // write back all registers
143 rManager.SpillAll();
144
145 // put result in $v0
146 if (stmt->GetOperand1()->GetOperandType() == OT_INT) {
147 mCode.AppendStatement(new MStatement(MOP_ADDI,
148 new MOperand(MT_REGISTER, R_V0),
149 new MOperand(MT_REGISTER, R_ZERO),
150 new MOperand(MT_INT, stmt->GetOperand1()->GetIntValue()),
151 "Store constant integer return value"));
152 } else {
153 MRegisterType result_reg = rManager.GetIntRegister(stmt->GetOperand1()->GetSymbol());
154 mCode.AppendStatement(new MStatement(MOP_MOVE,
155 new MOperand(MT_REGISTER, R_V0),
156 new MOperand(MT_REGISTER, result_reg),
157 "Store integer return value"));
158 }
159
160 // generate the epilogue
161 currentFrame.GenerateEpilogue(out);
162 break;
163 }
164 case IOP_RETURN_R: // [1--] Real function return
165 {
166 // The end of a subprogram:
167 // write back all registers
168 rManager.SpillAll();
169
170 // put result in $f0
171 if (stmt->GetOperand1()->GetOperandType() == OT_REAL) {
172 mCode.AppendStatement(new MStatement(MOP_LI_S,
173 new MOperand(MT_REGISTER, R_F0),
174 new MOperand(MT_REAL, stmt->GetOperand1()->GetRealValue()),
175 "Store constant real return value"));
176 } else if (stmt->GetOperand1()->GetOperandType() == OT_REAL) {
177 // XXX: is this needed?
178 mCode.AppendStatement(new MStatement(MOP_LI_S,
179 new MOperand(MT_REGISTER, R_F0),
180 new MOperand(MT_INT, stmt->GetOperand1()->GetRealValue()),
181 "Store real (casted from int) return value"));
182 } else {
183 MRegisterType result_reg = rManager.GetFloatRegister(stmt->GetOperand1()->GetSymbol());
184 mCode.AppendStatement(new MStatement(MOP_MOV_S,
185 new MOperand(MT_REGISTER, R_F0),
186 new MOperand(MT_REGISTER, result_reg),
187 "Store real return value"));
188 }
189
190 // generate the epilogue
191 currentFrame.GenerateEpilogue(out);
192 break;
193 }
194 /* Meta */
195 case IOP_UNKNOWN: // [---] (yet) Unknown operation
196 {
197 assert(0); // can't happen
198 break;
199 }
200 /* Parameter passing (caller side)
201 operand1 actual parameter value or Symbol object */
202 case IOP_PARAM_I: // [1--] Integer parameter
203 {
204 if (stmt->GetOperand1()->GetOperandType() == OT_INT) {
205 mCode.AppendStatement(new MStatement(MOP_ADDI,
206 new MOperand(MT_REGISTER, R_V1),
207 new MOperand(MT_REGISTER, R_ZERO),
208 new MOperand(MT_INT, stmt->GetOperand1()->GetIntValue()),
209 "Push constant integer parameter"));
210
211 } else {
212 // find/associate operand symbol to a register
213 MRegisterType operand_reg = rManager.GetIntRegister(stmt->GetOperand1()->GetSymbol());
214 mCode.AppendStatement(new MStatement(MOP_MOVE,
215 new MOperand(MT_REGISTER, R_V1),
216 new MOperand(MT_REGISTER, operand_reg),
217 "Push integer parameter"));
218 }
219
220 mCode.AppendStatement(new MStatement(MOP_SW,
221 new MOperand(MT_REGISTER, R_V1),
222 new MOperand(MT_OFFSET, R_SP, 0)));
223
224 mCode.AppendStatement(StackPointerChange(-4));
225 break;
226 }
227 case IOP_PARAM_R: // [1--] Real parameter
228 {
229 if (stmt->GetOperand1()->GetOperandType() == OT_REAL) {
230 mCode.AppendStatement(new MStatement(MOP_LI_S,
231 new MOperand(MT_REGISTER, R_F0),
232 new MOperand(MT_REAL, stmt->GetOperand1()->GetRealValue()),
233 "Push constant real parameter"));
234
235 } else {
236 // find/associate operand symbol to a register
237 MRegisterType operand_reg = rManager.GetFloatRegister(stmt->GetOperand1()->GetSymbol());
238 mCode.AppendStatement(new MStatement(MOP_MOV_S,
239 new MOperand(MT_REGISTER, R_F0),
240 new MOperand(MT_REGISTER, operand_reg),
241 "Push real parameter"));
242 }
243
244 mCode.AppendStatement(new MStatement(MOP_S_S,
245 new MOperand(MT_REGISTER, R_F0),
246 new MOperand(MT_OFFSET, R_SP, 0)));
247
248 mCode.AppendStatement(StackPointerChange(-4));
249 break;
250 }
251
252 /* Subprogram call
253 operand1 should refer to the corresponding Symbol object
254 result receives the result of a function call */
255 case IOP_PROCCALL: // [1--] Procedure call
256 {
257 /* making a procedure call so write back all registers */
258 rManager.SpillAll();
259 /* make procedure call */
260 mCode.AppendStatement(new MStatement(MOP_JAL,
261 new MOperand(MT_LABEL, string(SYMBOL_PREFIX) + OP1_NAME_C_STR(stmt))));
262 break;
263 }
264 case IOP_FUNCCALL: // [1-r] Function call
265 {
266 /* making a function call so write back all registers */
267 rManager.SpillAll();
268
269 /* Function call requires a call and then storage of returned data */
270 mCode.AppendStatement(new MStatement(MOP_JAL,
271 new MOperand(MT_LABEL, string(SYMBOL_PREFIX) + OP1_NAME_C_STR(stmt))));
272
273 /* find/associate a register and put the result in there */
274 Symbol *result_symbol = stmt->GetResult()->GetSymbol();
275 if (result_symbol->GetReturnType() == RT_INT) {
276 MRegisterType result_reg = rManager.GetIntRegister(result_symbol);
277 mCode.AppendStatement(new MStatement(MOP_MOVE,
278 new MOperand(MT_REGISTER, result_reg),
279 new MOperand(MT_REGISTER, R_V0),
280 "Store integer function result"));
281 } else {
282 MRegisterType result_reg = rManager.GetFloatRegister(result_symbol);
283 mCode.AppendStatement(new MStatement(MOP_MOV_S,
284 new MOperand(MT_REGISTER, result_reg),
285 new MOperand(MT_REGISTER, R_F0),
286 "Store real function result"));
287 }
288 break;
289 }
290 /* Label
291 operand1 should refer to the corresponding Symbol object */
292 case IOP_LABEL: // [1--] Label
293 {
294 MStatement *mstmt = new MStatement(MOP_LABEL);
295 mstmt->SetLabel(OP1_NAME_C_STR(stmt));
296 mCode.AppendStatement(mstmt);
297 break;
298 }
299 /* Goto
300 operand1 should refer to the corresponding Symbol object; note that
301 the Symbol pointed to should be of type ST_LABEL */
302 case IOP_GOTO: // [1--] Goto a label
303 {
304 /* changing control flow so write back all registers */
305 rManager.SpillAll();
306
307 mCode.AppendStatement(new MStatement(MOP_J, new MOperand(MT_LABEL, OP1_NAME_C_STR(stmt))));
308 break;
309 }
310 /* Variable assignment (copy value)
311 operand1 the source operand
312 result the destination operand (pointer to a Symbol object) */
313 case IOP_ASSIGN_I: // [1-r] Integer assignment
314 {
315 // find/associate result symbol to a register
316 MRegisterType result_reg = rManager.GetIntRegister(stmt->GetResult()->GetSymbol());
317
318 if (stmt->GetOperand1()->GetOperandType() == OT_INT) {
319 mCode.AppendStatement(new MStatement(MOP_ADDI,
320 new MOperand(MT_REGISTER, result_reg),
321 new MOperand(MT_REGISTER, R_ZERO),
322 new MOperand(MT_INT, stmt->GetOperand1()->GetIntValue()),
323 "Assign constant integer"));
324 } else {
325 // find/associate operand symbol to a register
326 MRegisterType operand_reg = rManager.GetIntRegister(stmt->GetOperand1()->GetSymbol());
327 mCode.AppendStatement(new MStatement(MOP_MOVE,
328 new MOperand(MT_REGISTER, result_reg),
329 new MOperand(MT_REGISTER, operand_reg),
330 "Assign integer"));
331 }
332 break;
333 }
334 case IOP_ASSIGN_R: // [1-r] Real assignment
335 {
336 // find/associate result symbol to a register
337 MRegisterType result_reg = rManager.GetFloatRegister(stmt->GetResult()->GetSymbol());
338
339 if (stmt->GetOperand1()->GetOperandType() == OT_REAL) {
340 mCode.AppendStatement(new MStatement(MOP_LI_S,
341 new MOperand(MT_REGISTER, result_reg),
342 new MOperand(MT_REAL, stmt->GetOperand1()->GetRealValue()),
343 "Assign constant real"));
344 } else {
345 // find/associate operand symbol to a register
346 MRegisterType operand_reg = rManager.GetFloatRegister(stmt->GetOperand1()->GetSymbol());
347 mCode.AppendStatement(new MStatement(MOP_MOV_S,
348 new MOperand(MT_REGISTER, result_reg),
349 new MOperand(MT_REGISTER, operand_reg),
350 "Assign real"));
351 }
352 break;
353
354 }
355 /* Branching
356 operand1 the first source operand
357 operand2 the second source operand
358 result should refer to the target Symbol object; note that
359 the Symbol pointed to must be of type ST_LABEL */
360 case IOP_BEQ_I: // [12r] = operator for integers
361 {
362 mCode.AppendStatement(BranchInstruction(MOP_BEQ, stmt));
363 break;
364 }
365 case IOP_BLT_I: // [12r] < operator for integers
366 {
367 mCode.AppendStatement(BranchInstruction(MOP_BLT, stmt));
368 break;
369 }
370 case IOP_BGT_I: // [12r] > operator for integers
371 {
372 mCode.AppendStatement(BranchInstruction(MOP_BGT, stmt));
373 break;
374 }
375 case IOP_BLE_I: // [12r] <= operator for integers
376 {
377 mCode.AppendStatement(BranchInstruction(MOP_BLE, stmt));
378 break;
379 }
380 case IOP_BGE_I: // [12r] >= operator for integers
381 {
382 mCode.AppendStatement(BranchInstruction(MOP_BGE, stmt));
383 break;
384 }
385 case IOP_BNE_I: // [12r] <> operator for integers
386 {
387 mCode.AppendStatement(BranchInstruction(MOP_BNE, stmt));
388 break;
389 }
390 case IOP_BEQ_R: // [12r] = operator for reals
391 {
392 mCode.AppendStatement(BranchInstructionReal(MOP_C_EQ_S, stmt));
393 mCode.AppendStatement(new MStatement(MOP_BCZT,
394 new MOperand(MT_LABEL, RESULT_NAME_C_STR(stmt))));
395 break;
396 }
397 case IOP_BLT_R: // [12r] < operator for reals
398 {
399 mCode.AppendStatement(BranchInstructionReal(MOP_C_LT_S, stmt));
400 mCode.AppendStatement(new MStatement(MOP_BCZT,
401 new MOperand(MT_LABEL, RESULT_NAME_C_STR(stmt))));
402 break;
403 }
404 case IOP_BGT_R: // [12r] > operator for reals
405 {
406 /* Use reverse style not (<=) */
407 mCode.AppendStatement(BranchInstructionReal(MOP_C_LT_S, stmt, true));
408 mCode.AppendStatement(new MStatement(MOP_BCZT,
409 new MOperand(MT_LABEL, RESULT_NAME_C_STR(stmt))));
410 break;
411 }
412 case IOP_BLE_R: // [12r] <= operator for reals
413 {
414 mCode.AppendStatement(BranchInstructionReal(MOP_C_LE_S, stmt));
415 mCode.AppendStatement(new MStatement(MOP_BCZT,
416 new MOperand(MT_LABEL, RESULT_NAME_C_STR(stmt))));
417 break;
418 }
419 case IOP_BGE_R: // [12r] >= operator for reals
420 {
421 mCode.AppendStatement(BranchInstructionReal(MOP_C_LE_S, stmt, true));
422 mCode.AppendStatement(new MStatement(MOP_BCZF,
423 new MOperand(MT_LABEL, RESULT_NAME_C_STR(stmt))));
424 break;
425 }
426 case IOP_BNE_R: // [12r] <> operator for reals
427 {
428 mCode.AppendStatement(BranchInstructionReal(MOP_C_EQ_S, stmt));
429 mCode.AppendStatement(new MStatement(MOP_BCZF,
430 new MOperand(MT_LABEL, RESULT_NAME_C_STR(stmt))));
431 break;
432 }
433
434 /* Binary arithmetic operators
435 operand1 the first source operand
436 operand2 the second source operand
437 result the destination operand (refers to a Symbol object) */
438 case IOP_ADD_I: // [12r] Integer addition
439 {
440 mCode.AppendStatement(BinaryArithmetic(MOP_ADD, stmt, "Add integers"));
441 break;
442 }
443 case IOP_ADD_R: // [12r] Real addition
444 {
445 mCode.AppendStatement(BinaryArithmetic(MOP_ADD_S, stmt, "Add reals"));
446 break;
447 }
448 case IOP_SUB_I: // [12r] Integer substraction
449 {
450 mCode.AppendStatement(BinaryArithmetic(MOP_SUB, stmt, "Subtract integer"));
451 break;
452 }
453 case IOP_SUB_R: // [12r] Real substraction
454 {
455 mCode.AppendStatement(BinaryArithmetic(MOP_SUB_S, stmt, "Subtract reals"));
456 break;
457 }
458 case IOP_MUL_I: // [12r] Integer multiplication
459 {
460 mCode.AppendStatement(BinaryArithmetic(MOP_MUL, stmt, "Multiply integers"));
461 break;
462 }
463 case IOP_MUL_R: // [12r] Real multiplication
464 {
465 mCode.AppendStatement(BinaryArithmetic(MOP_MUL_S, stmt, "Multiply reals"));
466 break;
467 }
468 case IOP_DIV_I: // [12r] Integer division
469 {
470 mCode.AppendStatement(BinaryArithmetic(MOP_DIV, stmt, "Divide integers"));
471 break;
472 }
473 case IOP_DIV_R: // [12r] Real division
474 {
475 mCode.AppendStatement(BinaryArithmetic(MOP_DIV_S, stmt, "Divide reals"));
476 break;
477 }
478 case IOP_MOD: // [12r] Modulo
479 {
480 mCode.AppendStatement(BinaryArithmetic(MOP_REM, stmt, "Remainder"));
481 break;
482 }
483 case IOP_AND: // [12r] AND operation
484 {
485 mCode.AppendStatement(BinaryArithmetic(MOP_AND, stmt, "Bitwise and"));
486 break;
487 }
488 case IOP_OR: // [12r] OR operation
489 {
490 mCode.AppendStatement(BinaryArithmetic(MOP_OR, stmt, "Bitwise or"));
491 break;
492 }
493
494 /* Unary arithmetic operators
495 operand1 the source operand
496 result the destination operand (refers to a Symbol object) */
497 case IOP_NOT: // [1-r] NOT operation
498 {
499 mCode.AppendStatement(UnaryArithmetic(MOP_NOT, stmt, "Bitwise not"));
500 break;
501 }
502 case IOP_UNARY_MINUS_I: // [1-r] Unary integer minus
503 {
504 mCode.AppendStatement(UnaryArithmetic(MOP_NEG, stmt, "Negate integer"));
505 break;
506 }
507 case IOP_UNARY_MINUS_R: // [1-r] Unary real minus
508 {
509 mCode.AppendStatement(UnaryArithmetic(MOP_NEG_S, stmt, "Negate real"));
510 break;
511 }
512 /* Coercion
513 operand1 the source operand
514 result the destination operand (refers to a Symbol object) */
515 case IOP_INT_TO_REAL: // [1-r] Int to Real coercion
516 {
517 MRegisterType dest_reg = rManager.GetFloatRegister(stmt->GetResult()->GetSymbol());
518 if (stmt->GetOperand1()->GetOperandType() == OT_INT) {
519 // just add constant
520 float value = stmt->GetOperand1()->GetIntValue();
521 mCode.AppendStatement(new MStatement(MOP_LI_S,
522 new MOperand(MT_REGISTER, dest_reg),
523 new MOperand(MT_REAL, value),
524 "Coerce constant from int to real"));
525 } else {
526 // load integer into register and load it into floating point register
527 MRegisterType source_reg = rManager.GetIntRegister(stmt->GetOperand1()->GetSymbol());
528 mCode.AppendStatement(new MStatement(MOP_MTC1,
529 new MOperand(MT_REGISTER, source_reg),
530 new MOperand(MT_REGISTER, dest_reg),
531 "Coerce from int to real"));
532 // convert integer to float
533 mCode.AppendStatement(new MStatement(MOP_CVT_S_W,
534 new MOperand(MT_REGISTER, dest_reg),
535 new MOperand(MT_REGISTER, dest_reg)));
536 }
537 break;
538 }
539 default:
540 fprintf(stderr,
541 "[CodeGenerator::GenerateCode()] Unhandled intermediate operator '%s'\n",
542 IOperatorToString(stmt->GetOperator())
543 );
544 }
545 }
546}
547
548MOperand * CodeGenerator::IOperand2MOperand(IOperand * opnd) {
549 MOperand *retVal;
550 MRegisterType freeRegister;
551 switch (opnd->GetOperandType()) {
552 case OT_SYMBOL:
553 {
554 MRegisterType tmpReg = rManager.GetRegister(opnd->GetSymbol());
555 retVal = new MOperand(MT_REGISTER, tmpReg);
556 break;
557 }
558 case OT_INT:
559 {
560 freeRegister = rManager.GetTempRegister();
561 mCode.AppendStatement(new MStatement(MOP_ADDI,
562 new MOperand(MT_REGISTER, freeRegister),
563 new MOperand(MT_REGISTER, R_ZERO),
564 new MOperand(MT_INT, opnd->GetIntValue())));
565
566 retVal = new MOperand(MT_REGISTER, freeRegister);
567 break;
568 }
569 case OT_REAL:
570 {
571 freeRegister = rManager.GetTempRegister();
572 mCode.AppendStatement(new MStatement(MOP_LI_S,
573 new MOperand(MT_REGISTER, freeRegister),
574 new MOperand(MT_REAL, opnd->GetRealValue())));
575
576 retVal = new MOperand(MT_REGISTER, freeRegister);
577 break;
578 }
579 default:
580 /* XXX: Should not happen */
581 break;
582 }
583 return (retVal);
584}
585
586// Generates a trailer
587
588/* Stack Pointer template */
589MStatement * CodeGenerator::StackPointerChange(int offset,
590 const char * comment) {
591 MOperand *mop1 = new MOperand(MT_REGISTER, R_SP);
592 MOperand *mop2 = new MOperand(MT_REGISTER, R_SP);
593 MOperand *mop3 = new MOperand(MT_INT, offset);
594 return (new MStatement(MOP_ADDI, mop1, mop2, mop3, comment));
595}
596
597/* Unary Artithmetic template */
598MStatement * CodeGenerator::UnaryArithmetic(MOperator opcode, IStatement *stmt,
599 const char * comment) {
600 MOperand *mop1 = IOperand2MOperand(stmt->GetResult());
601 MOperand *mop2 = IOperand2MOperand(stmt->GetOperand1());
602
603 return (new MStatement(opcode, mop1, mop2, comment));
604}
605
606/* Binary Artithmetic template */
607MStatement * CodeGenerator::BinaryArithmetic(MOperator opcode, IStatement *stmt,
608 const char * comment) {
609 MOperand *mop1 = IOperand2MOperand(stmt->GetResult());
610 MOperand *mop2 = IOperand2MOperand(stmt->GetOperand1());
611 MOperand *mop3 = IOperand2MOperand(stmt->GetOperand2());
612
613 return (new MStatement(opcode, mop1, mop2, mop3, comment));
614
615}
616
617/* Branch Instruction with Int values template */
618MStatement * CodeGenerator::BranchInstruction(MOperator opcode, IStatement *stmt,
619 bool swap, const char * comment) {
620 MOperand *mop1 = IOperand2MOperand(stmt->GetOperand1());
621 MOperand *mop2 = IOperand2MOperand(stmt->GetOperand2());
622 MOperand *mop3 = new MOperand(MT_LABEL, stmt->GetResult()->GetSymbol()->GetName());
623
624 /* changing control flow so write back all registers */
625 rManager.SpillAll();
626
627 if (swap)
628 return (new MStatement(opcode, mop1, mop2, mop3, comment));
629 else
630 return (new MStatement(opcode, mop2, mop1, mop3, comment));
631}
632
633/* Branch Instruction with Real values temlate */
634MStatement * CodeGenerator::BranchInstructionReal(MOperator opcode, IStatement *stmt,
635 bool swap, const char * comment) {
636 MOperand *mop1 = IOperand2MOperand(stmt->GetOperand1());
637 MOperand *mop2 = IOperand2MOperand(stmt->GetOperand2());
638 if (swap)
639 return (new MStatement(opcode, mop1, mop2, comment));
640 else
641 return (new MStatement(opcode, mop2, mop1, comment));
642}
643
644void CodeGenerator::Dump(FILE * out) {
645 mCode.Dump(out);
646 fprintf(out, "\n");
647}
648
649void CodeGenerator::GenerateTrailer(FILE *) {
650 /* readinteger: syscall code 5, integer in $v0
651 * General idea: init, set syscall value, call syscall, save value
652 */
653 {
654 mCode.AppendStatement(new MStatement(MOP_ENT,
655 new MOperand(MT_LABEL, string(SYMBOL_PREFIX) + string("readinteger")),
656 "Start of builtin functions and procedures"));
657
658 MStatement *stmt = new MStatement(MOP_LABEL);
659 stmt->SetLabel(string(SYMBOL_PREFIX) + string("readinteger"));
660 mCode.AppendStatement(stmt);
661
662 mCode.AppendStatement(new MStatement(MOP_ADDI,
663 new MOperand(MT_REGISTER, R_V0),
664 new MOperand(MT_REGISTER, R_ZERO),
665 new MOperand(MT_INT, 5)));
666
667 mCode.AppendStatement(new MStatement(MOP_SYSCALL));
668
669 mCode.AppendStatement(new MStatement(MOP_JR,
670 new MOperand(MT_REGISTER, R_RA)));
671
672 mCode.AppendStatement(new MStatement(MOP_END,
673 new MOperand(MT_LABEL, string(SYMBOL_PREFIX) + string("readinteger"))));
674 }
675
676 /* writeinteger: syscall code 1, integer in $a0
677 * General idea: init, set syscall value, ,set value, call syscall
678 */
679 {
680 mCode.AppendStatement(new MStatement(MOP_ENT,
681 new MOperand(MT_LABEL, string(SYMBOL_PREFIX) + string("writeinteger"))));
682
683 MStatement *stmt = new MStatement(MOP_LABEL);
684 stmt->SetLabel(string(SYMBOL_PREFIX) + string("writeinteger"));
685 mCode.AppendStatement(stmt);
686
687 mCode.AppendStatement(new MStatement(MOP_LW,
688 new MOperand(MT_REGISTER, R_A0),
689 new MOperand(MT_OFFSET, R_SP, 4)));
690
691 mCode.AppendStatement(new MStatement(MOP_ADDI,
692 new MOperand(MT_REGISTER, R_V0),
693 new MOperand(MT_REGISTER, R_ZERO),
694 new MOperand(MT_INT, 1)));
695
696 mCode.AppendStatement(new MStatement(MOP_SYSCALL));
697
698 mCode.AppendStatement(StackPointerChange(4));
699
700 mCode.AppendStatement(new MStatement(MOP_JR,
701 new MOperand(MT_REGISTER, R_RA)));
702
703 mCode.AppendStatement(new MStatement(MOP_END,
704 new MOperand(MT_LABEL, string(SYMBOL_PREFIX) + string("writeinteger"))));
705 }
706
707 /* readreal: syscall code 6, float in $f0
708 * General idea: init, set syscall value, call syscall, save value
709 */
710 {
711 mCode.AppendStatement(new MStatement(MOP_ENT,
712 new MOperand(MT_LABEL, string(SYMBOL_PREFIX) + string("readreal"))));
713
714 MStatement *stmt = new MStatement(MOP_LABEL);
715 stmt->SetLabel(string(SYMBOL_PREFIX) + string("readreal"));
716 mCode.AppendStatement(stmt);
717
718 mCode.AppendStatement(new MStatement(MOP_ADDI,
719 new MOperand(MT_REGISTER, R_V0),
720 new MOperand(MT_REGISTER, R_ZERO),
721 new MOperand(MT_INT, 6)));
722
723 mCode.AppendStatement(new MStatement(MOP_SYSCALL));
724
725 mCode.AppendStatement(new MStatement(MOP_JR,
726 new MOperand(MT_REGISTER, R_RA)));
727
728 mCode.AppendStatement(new MStatement(MOP_END,
729 new MOperand(MT_LABEL, string(SYMBOL_PREFIX) + string("readreal"))));
730 }
731
732 /* writereal: syscall code 2, float in $f12
733 * General idea: init, set syscall value, ,set value, call syscall
734 */
735 {
736 mCode.AppendStatement(new MStatement(MOP_ENT,
737 new MOperand(MT_LABEL, string(SYMBOL_PREFIX) + string("writereal"))));
738
739 MStatement *stmt = new MStatement(MOP_LABEL);
740 stmt->SetLabel(string(SYMBOL_PREFIX) + string("writereal"));
741 mCode.AppendStatement(stmt);
742
743 mCode.AppendStatement(new MStatement(MOP_L_S,
744 new MOperand(MT_REGISTER, R_F12),
745 new MOperand(MT_OFFSET, R_SP, 4)));
746
747 mCode.AppendStatement(new MStatement(MOP_ADDI,
748 new MOperand(MT_REGISTER, R_V0),
749 new MOperand(MT_REGISTER, R_ZERO),
750 new MOperand(MT_INT, 2)));
751
752 mCode.AppendStatement(new MStatement(MOP_SYSCALL));
753
754 mCode.AppendStatement(StackPointerChange(4));
755
756 mCode.AppendStatement(new MStatement(MOP_JR,
757 new MOperand(MT_REGISTER, R_RA)));
758
759 mCode.AppendStatement(new MStatement(MOP_END,
760 new MOperand(MT_LABEL, string(SYMBOL_PREFIX) + string("writereal"))));
761 }
762}
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