Line No. | Rev | Author | Line |
---|---|---|---|
1 | 32 | kaklik | /********************************************************************** |
2 | * |
||
3 | * Big Integer Assembly Helpers |
||
4 | * Library for Microchip TCP/IP Stack |
||
5 | * - Accelerates processing for BigInt functions |
||
6 | * |
||
7 | ********************************************************************** |
||
8 | * FileName: BigInt_helper_C32.S |
||
9 | * Dependencies: None |
||
10 | * Processor: PIC32 |
||
11 | * Compiler: Microchip C32 v1.05 or higher |
||
12 | * Company: Microchip Technology, Inc. |
||
13 | * |
||
14 | * Software License Agreement |
||
15 | * |
||
16 | * Copyright (C) 2002-2009 Microchip Technology Inc. All rights |
||
17 | * reserved. |
||
18 | * |
||
19 | * Microchip licenses to you the right to use, modify, copy, and |
||
20 | * distribute: |
||
21 | * (i) the Software when embedded on a Microchip microcontroller or |
||
22 | * digital signal controller product ("Device") which is |
||
23 | * integrated into Licensee's product; or |
||
24 | * (ii) ONLY the Software driver source files ENC28J60.c, ENC28J60.h, |
||
25 | * ENCX24J600.c and ENCX24J600.h ported to a non-Microchip device |
||
26 | * used in conjunction with a Microchip ethernet controller for |
||
27 | * the sole purpose of interfacing with the ethernet controller. |
||
28 | * |
||
29 | * You should refer to the license agreement accompanying this |
||
30 | * Software for additional information regarding your rights and |
||
31 | * obligations. |
||
32 | * |
||
33 | * THE SOFTWARE AND DOCUMENTATION ARE PROVIDED "AS IS" WITHOUT |
||
34 | * WARRANTY OF ANY KIND, EITHER EXPRESS OR IMPLIED, INCLUDING WITHOUT |
||
35 | * LIMITATION, ANY WARRANTY OF MERCHANTABILITY, FITNESS FOR A |
||
36 | * PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT SHALL |
||
37 | * MICROCHIP BE LIABLE FOR ANY INCIDENTAL, SPECIAL, INDIRECT OR |
||
38 | * CONSEQUENTIAL DAMAGES, LOST PROFITS OR LOST DATA, COST OF |
||
39 | * PROCUREMENT OF SUBSTITUTE GOODS, TECHNOLOGY OR SERVICES, ANY CLAIMS |
||
40 | * BY THIRD PARTIES (INCLUDING BUT NOT LIMITED TO ANY DEFENSE |
||
41 | * THEREOF), ANY CLAIMS FOR INDEMNITY OR CONTRIBUTION, OR OTHER |
||
42 | * SIMILAR COSTS, WHETHER ASSERTED ON THE BASIS OF CONTRACT, TORT |
||
43 | * (INCLUDING NEGLIGENCE), BREACH OF WARRANTY, OR OTHERWISE. |
||
44 | * |
||
45 | * |
||
46 | * Author Date Comment |
||
47 | *~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ |
||
48 | * Abhay Deshmukh 03/04/08 Original |
||
49 | *********************************************************************/ |
||
50 | |||
51 | #define __GENERIC_TYPE_DEFS_H_ |
||
52 | #define __COMPILER_H |
||
53 | #include "HardwareProfile.h" |
||
54 | #include "TCPIPConfig.h" |
||
55 | #if (defined(STACK_USE_SSL_SERVER) || defined(STACK_USE_SSL_CLIENT)) && !defined(ENC100_INTERFACE_MODE) |
||
56 | |||
57 | #include "TCPIP Stack/regdef.h" |
||
58 | |||
59 | #define MAX_UNSIGNED_INT_VALUE 0xFFFFFFFF |
||
60 | |||
61 | #define ONE_VALUE 0x00000001 |
||
62 | |||
63 | #define ZERO_VALUE 0x00000000 |
||
64 | |||
65 | .bss |
||
66 | .align 4 |
||
67 | .global _iA |
||
68 | .global _xA |
||
69 | .global _iB |
||
70 | .global _xB |
||
71 | .global _iR |
||
72 | .global _wC |
||
73 | _iA: .word 4 /* _iA, starting index for A (lower memory address, least significant byte/word) */ |
||
74 | _xA: .word 4 /* _xA, end index for A (higher memory address, most significant byte/word) */ |
||
75 | _iB: .word 4 /* _iB, starting index for B (lower memory address, least significant byte/word) */ |
||
76 | _xB: .word 4 /* _xB, end index for B (higher memory address, most significant byte/word) */ |
||
77 | _iR: .word 4 /* _iR, starting index for Res (lower memory address, least significant byte/word) */ |
||
78 | _wC: .word 4 /* value of B for _mas (little endian word) */ |
||
79 | |||
80 | .set noreorder |
||
81 | |||
82 | .text |
||
83 | |||
84 | /*************************************************************************** |
||
85 | ; Function: void _addBI() |
||
86 | ; |
||
87 | ; PreCondition: _iA and _iB are loaded with the address of the LSB of the BigInt |
||
88 | ; _xA and _xB are loaded with the address of the MSB of the BigInt |
||
89 | ; a.size >= b.magnitude |
||
90 | ; |
||
91 | ; Input: A and B, the BigInts to add |
||
92 | ; |
||
93 | ; Output: A = A + B |
||
94 | ; |
||
95 | ; Side Effects: None |
||
96 | ; |
||
97 | ; Overview: Quickly performs the bulk addition of two BigInts |
||
98 | ; |
||
99 | ; Note: Function works |
||
100 | ;***************************************************************************/ |
||
101 | |||
102 | /* Note :- There is no Carry/Borrow Flag in STATUS Register of PIC32...So Workarounds were done */ |
||
103 | |||
104 | .global _addBI |
||
105 | |||
106 | .ent _addBI |
||
107 | |||
108 | _addBI: |
||
109 | la t0, _xA # Load adress of _xA |
||
110 | lw t0, 0(t0) # Load the Contents of memory pointing by t0 register |
||
111 | |||
112 | la t1, _iA |
||
113 | addiu t0, t0, 4 # Store the address present in _xA & increment it by 4 ( since every access is 32 bit ) |
||
114 | lw t1, 0(t1) # Store the address present in __iA |
||
115 | |||
116 | la t2, _xB |
||
117 | lw t2, 0(t2) |
||
118 | |||
119 | la t3, _iB |
||
120 | addiu t2, t2, 4 # Store the address present in _xB & increment it by 4 |
||
121 | lw t3, 0(t3) # Store the address present in _iB |
||
122 | |||
123 | la t6, ZERO_VALUE # Store 0x00000000 in t6 |
||
124 | |||
125 | aDoAdd: |
||
126 | lw t4, 0(t3) # Place the LSW of _iB in t4 |
||
127 | addiu t3, t3, 4 # t3 = t3 + t4 |
||
128 | lw t5, 0(t1) # Place the LSW of _iA in t5 |
||
129 | addu t5, t5, t6 # t5 = t5 + t6 |
||
130 | addu t7, t5, t4 # t7 = t5 + t4 |
||
131 | sw t7, 0(t1) # 4 bytes of data transfered from address specified by t1 to t5 |
||
132 | sltu t8, t7, t5 # if ( t7 < t5 ) then ( t8 = 1 ) |
||
133 | movz t8, t6, t5 |
||
134 | move t6, t8 # PrevCarry = carry |
||
135 | bne t3, t2, aDoAdd # if t3 != t2 then Jump to 'aDoAdd' |
||
136 | addiu t1, t1, 4 |
||
137 | beqz t6, addDone |
||
138 | nop |
||
139 | |||
140 | AddCarry: |
||
141 | beq t0, t1, addDone # if t0 = t1 then Jump to 'nextDoadd' |
||
142 | lw t7, 0(t1) |
||
143 | addiu t5, t7, 1 |
||
144 | sw t5, 0(t1) # Store the Contents of t5 in memory pointed by t1 register |
||
145 | addiu t1, t1, 4 |
||
146 | beqz t7, AddCarry |
||
147 | nop |
||
148 | |||
149 | addDone: |
||
150 | jr $ra # return to function from where you are called |
||
151 | nop |
||
152 | |||
153 | .end _addBI |
||
154 | |||
155 | |||
156 | /*************************************************************************** |
||
157 | ; Function: void _subBI() |
||
158 | ; |
||
159 | ; PreCondition: _iA and _iB are loaded with the address of the LSB of the BigInt |
||
160 | ; _xA and _xB are loaded with the address of the MSB of the BigInt |
||
161 | ; |
||
162 | ; Input: A and B, the BigInts to subtract |
||
163 | ; |
||
164 | ; Output: A = A - B |
||
165 | ; |
||
166 | ; Side Effects: None |
||
167 | ; |
||
168 | ; Overview: Quickly performs the bulk subtraction of two BigInts |
||
169 | ; |
||
170 | ; Note: Function works |
||
171 | ;***************************************************************************/ |
||
172 | .global _subBI |
||
173 | |||
174 | .ent _subBI |
||
175 | |||
176 | _subBI: |
||
177 | la t0, _xA |
||
178 | lw t0, 0(t0) # Store the address present in __xA & increment it by 4 |
||
179 | |||
180 | la t1, _iA # Store the address present in __iA |
||
181 | addiu t0, t0, 4 |
||
182 | lw t1, 0(t1) |
||
183 | |||
184 | la t2, _xB # Store the address present in __xB & increment it by 4 |
||
185 | lw t2, 0(t2) |
||
186 | |||
187 | la t3, _iB # Store the address present in __iB |
||
188 | addiu t2, t2, 4 |
||
189 | lw t3, 0(t3) |
||
190 | |||
191 | la t6, ZERO_VALUE # Store 0x00000000 in t6 |
||
192 | |||
193 | sDoSub: |
||
194 | move t8,$0 |
||
195 | lw t4, 0(t3) # Place the LSW of __iB in t4 |
||
196 | addiu t3, t3, 4 # t3 = t3 + t4 |
||
197 | lw t5, 0(t1) # Place the LSW of __iA in t5 |
||
198 | movz t8, t6, t5 |
||
199 | subu t5, t5, t6 # t8 = t5 - t6 |
||
200 | sltu t7, t5, t4 # if ( t8 < t4 ) then ( t7 = 1 ) |
||
201 | subu t5, t5, t4 # t5 = t5 - t4 |
||
202 | sw t5, 0(t1) # 4 bytes of data transfered from address specified by t1 to t5 |
||
203 | or t7, t7, t8 |
||
204 | move t6, t7 |
||
205 | bne t3, t2, sDoSub |
||
206 | addiu t1, t1, 4 |
||
207 | beqz t6, subDone |
||
208 | nop |
||
209 | |||
210 | SubBorrow: |
||
211 | beq t0, t1, subDone |
||
212 | lw t7, 0(t1) |
||
213 | addiu t5, t7, -1 |
||
214 | sw t5, 0(t1) |
||
215 | addiu t1, t1, 4 |
||
216 | beq t7,$0, SubBorrow |
||
217 | nop |
||
218 | |||
219 | subDone: |
||
220 | jr $ra |
||
221 | nop |
||
222 | |||
223 | .end _subBI |
||
224 | |||
225 | |||
226 | /*************************************************************************** |
||
227 | ; Function: void _zeroBI() |
||
228 | ; |
||
229 | ; PreCondition: _iA is loaded with the address of the LSB of the BigInt |
||
230 | ; _xA is loaded with the address of the MSB of the BigInt |
||
231 | ; |
||
232 | ; Input: None |
||
233 | ; |
||
234 | ; Output: A = 0 |
||
235 | ; |
||
236 | ; Side Effects: None |
||
237 | ; |
||
238 | ; Overview: Sets all words from _iA to _xA to zero |
||
239 | ; |
||
240 | ; Note: Function works |
||
241 | ;***************************************************************************/ |
||
242 | .global _zeroBI |
||
243 | |||
244 | .ent _zeroBI |
||
245 | |||
246 | _zeroBI: |
||
247 | |||
248 | la t0, _xA |
||
249 | lw t0, 0(t0) # Store the address present in __xA & increment it by 4 |
||
250 | |||
251 | la t1, _iA # Store the address present in __iA |
||
252 | addiu t0, t0, 4 |
||
253 | lw t1, 0(t1) |
||
254 | |||
255 | zDoZero: |
||
256 | sw $0, 0(t1) # The value of $0 register is always 0 |
||
257 | addiu t1, t1, 4 |
||
258 | bne t0, t1, zDoZero |
||
259 | nop |
||
260 | jr $ra |
||
261 | nop |
||
262 | |||
263 | .end _zeroBI |
||
264 | |||
265 | |||
266 | /*************************************************************************** |
||
267 | ; Function: void _msbBI() |
||
268 | ; |
||
269 | ; PreCondition: _iA is loaded with the address of the LSB of the BigInt buffer |
||
270 | ; _xA is loaded with the address of the right most byte of the BigInt buffer |
||
271 | ; |
||
272 | ; Input: None |
||
273 | ; |
||
274 | ; Output: _xA is now pointing to the MSB of the BigInt |
||
275 | ; |
||
276 | ; Side Effects: None |
||
277 | ; |
||
278 | ; Overview: Finds the MSB (first non-zero word) of the BigInt, starting |
||
279 | ; from the right-most word and testing to the left. This |
||
280 | ; function will stop if _iA is reached. |
||
281 | ; |
||
282 | ; Note: Function works |
||
283 | ;***************************************************************************/ |
||
284 | .global _msbBI |
||
285 | |||
286 | .ent _msbBI |
||
287 | |||
288 | _msbBI: |
||
289 | |||
290 | la t2, _xA |
||
291 | lw t0, 0(t2) # Store the address present in __xA & increment it by 4 |
||
292 | |||
293 | la t1, _iA # Store the address present in __iA |
||
294 | lw t1, 0(t1) |
||
295 | |||
296 | msbLoop: |
||
297 | lw t3, 0(t0) |
||
298 | bne t3, $0, msbDone |
||
299 | nop |
||
300 | addiu t0, t0, -4 |
||
301 | bne t0, t1, msbLoop |
||
302 | nop |
||
303 | |||
304 | msbDone: |
||
305 | sw t0, 0(t2) |
||
306 | jr $ra |
||
307 | nop |
||
308 | |||
309 | .end _msbBI |
||
310 | |||
311 | |||
312 | /*************************************************************************** |
||
313 | ; Function: void _mulBI() |
||
314 | ; |
||
315 | ; PreCondition: _iA and _iB are loaded with the address of the LSB of each BigInt |
||
316 | ; _xA and _xB are loaded with the address of the MSB of the BigInt |
||
317 | ; _iR is loaded with the LSB address of the destination result memory |
||
318 | ; _iR memory must be zeroed and have enough space (_xB-_iB+_xA-_iA words) |
||
319 | ; |
||
320 | ; Input: A and B, the BigInts to multiply |
||
321 | ; |
||
322 | ; Output: R = A * B |
||
323 | ; |
||
324 | ; Side Effects: None |
||
325 | ; |
||
326 | ; Overview: Performs the bulk multiplication of two BigInts |
||
327 | ; |
||
328 | ; Note: Function works. An Assumption has been made that 'R' is cleared to |
||
329 | ; 'Zero' before calling this function. |
||
330 | ;***************************************************************************/ |
||
331 | |||
332 | .global _mulBI |
||
333 | |||
334 | .ent _mulBI |
||
335 | |||
336 | _mulBI: |
||
337 | |||
338 | la t0, _xA |
||
339 | lw t0, 0(t0) # Store the address present in _xA & increment it by 4 |
||
340 | |||
341 | la t1, _iA # Store the address present in _iA |
||
342 | addiu t0, t0, 4 |
||
343 | lw t1, 0(t1) |
||
344 | |||
345 | la t2, _xB # Store the address present in _xB & increment it by 4 |
||
346 | lw t2, 0(t2) |
||
347 | |||
348 | la t3, _iB # Store the address present in _iB |
||
349 | addiu t2, t2, 4 |
||
350 | lw t3, 0(t3) |
||
351 | |||
352 | la t4, _iR # Store the address present in _iR |
||
353 | lw t4, 0(t4) |
||
354 | |||
355 | la a0, ONE_VALUE # Store 0x00000001 in a0 |
||
356 | |||
357 | addiu t6, $0, 0 # Store 0x0 in t6 |
||
358 | |||
359 | mLoopB: |
||
360 | beq t3, t2, mDone |
||
361 | lw t7, 0(t3) |
||
362 | |||
363 | beq t7, $0, mContinue |
||
364 | addu t8, t4, t6 |
||
365 | |||
366 | mthi $0 # Move 0 to HI Register. |
||
367 | |||
368 | addiu t5, t1, 0 |
||
369 | |||
370 | mLoopA: |
||
371 | mfhi a1 # Store the contents from HI Register to 'a1' register |
||
372 | lw a3,0(t8) |
||
373 | addu a2, a1, a3 |
||
374 | mtlo a2 # Move the contents from 'a1' register to LO register |
||
375 | sltu a1, a2, a1 |
||
376 | bgtz a1, mHiPutOne |
||
377 | nop |
||
378 | b mMultAdd |
||
379 | mthi $0 |
||
380 | |||
381 | mHiPutOne: |
||
382 | mthi a0 # Move the contents from 'a0' register to HI register |
||
383 | |||
384 | mMultAdd: |
||
385 | lw a1, 0(t5) |
||
386 | maddu a1, t7 # Multiply a1 with t7 then add with HI || LO register ( i.e HI || LO + a1 * t7 ) |
||
387 | addiu t5, t5, 4 |
||
388 | mflo a3 # Store the contents from LO Register to 'a3' register |
||
389 | sw a3,0(t8) |
||
390 | addiu t8, t8, 4 |
||
391 | bne t5,t0, mLoopA |
||
392 | nop |
||
393 | mfhi a1 # Store the contents from HI Register to 'a1' register |
||
394 | sw a1, 0(t8) # Move the contents from 'a1' register to LO register |
||
395 | |||
396 | mContinue: |
||
397 | addiu t3, t3, 4 |
||
398 | b mLoopB |
||
399 | addiu t6, t6, 4 |
||
400 | |||
401 | mDone: |
||
402 | jr $ra |
||
403 | nop |
||
404 | |||
405 | .end _mulBI |
||
406 | |||
407 | |||
408 | /*************************************************************************** |
||
409 | ; Function: void _sqrBI() |
||
410 | ; |
||
411 | ; PreCondition: _iA is loaded with the address of the LSB of the BigInt |
||
412 | ; _xA is loaded with the address of the MSB of the BigInt |
||
413 | ; _iR is loaded with the LSB address of the destination result memory |
||
414 | ; _iR memory must be zeroed and have enough space (_xB-_iB+_xA-_iA words) |
||
415 | ; |
||
416 | ; Input: A, the BigInt to square |
||
417 | ; |
||
418 | ; Output: R = A * A |
||
419 | ; |
||
420 | ; Side Effects: None |
||
421 | ; |
||
422 | ; Overview: Squares BigInt A and stores result in R |
||
423 | ; |
||
424 | ; Note: Function works |
||
425 | ;***************************************************************************/ |
||
426 | .global _sqrBI |
||
427 | |||
428 | .ent _sqrBI |
||
429 | |||
430 | _sqrBI: |
||
431 | |||
432 | la t0, _xA |
||
433 | lw t0, 0(t0) # Store the address present in _xA & increment it by 4 |
||
434 | |||
435 | la t1, _xB # Store the address present in _xB & increment it by 4 |
||
436 | sw t0, 0(t1) |
||
437 | |||
438 | la t0, _iA # Store the address present in _iA |
||
439 | lw t0, 0(t0) |
||
440 | |||
441 | la t1, _iB # Store the address present in _iB |
||
442 | |||
443 | b _mulBI |
||
444 | sw t0, 0(t1) |
||
445 | |||
446 | .end _sqrBI |
||
447 | |||
448 | /*************************************************************************** |
||
449 | ; Function: void _masBI() |
||
450 | ; |
||
451 | ; PreCondition: _iB is loaded with the LSB of the modulus BigInt |
||
452 | ; _xB is loaded with the MSB of the modulus BigInt |
||
453 | ; _wC is loaded with the 32 bit unsigned integer by which to multiply |
||
454 | ; _iR is the starting LSB of the decumulator BigInt |
||
455 | .end __sqrBI |
||
456 | ; |
||
457 | ; Input: B (BigInt) and C (16-bit int) to multiply |
||
458 | ; |
||
459 | ; Output: R = R - (B * C) |
||
460 | ; |
||
461 | ; Side Effects: None |
||
462 | ; |
||
463 | ; Overview: Performs a Multiply And Subtract function. This is used in |
||
464 | ; the modulus calculation to save several steps. A BigInt (iB/xB) |
||
465 | ; is multiplied by a single word and subtracted rather than |
||
466 | ; accumulated. |
||
467 | ; |
||
468 | ; Note: Decumulator is the opposite of an accumulator, |
||
469 | ; if that wasn't obvious |
||
470 | ; |
||
471 | ; Note: Function works |
||
472 | ;***************************************************************************/ |
||
473 | .global _masBI |
||
474 | |||
475 | .ent _masBI |
||
476 | |||
477 | _masBI: |
||
478 | |||
479 | la t2, _xB # Store the address present in _xB & increment it by 4 |
||
480 | lw t2, 0(t2) |
||
481 | |||
482 | la t3, _iB # Store the address present in _iB |
||
483 | addiu t2, t2, 4 |
||
484 | lw t3, 0(t3) |
||
485 | |||
486 | la t1, _wC # Store the address present in _wC |
||
487 | lw t1, 0(t1) |
||
488 | |||
489 | la t4, _iR # Store the address present in _iR |
||
490 | lw t4, 0(t4) |
||
491 | |||
492 | la a1, ZERO_VALUE |
||
493 | |||
494 | subu t8, t2, t3 |
||
495 | addiu t8, t8, 4 |
||
496 | addiu t9, t4, 0 |
||
497 | addiu a0, $0, 1 |
||
498 | |||
499 | masLoop: |
||
500 | |||
501 | mthi $0 |
||
502 | mfhi t6 |
||
503 | |||
504 | mMultandSub: |
||
505 | mtlo t6 |
||
506 | mthi $0 |
||
507 | lw t5, 0(t3) |
||
508 | maddu t5, t1 |
||
509 | nop |
||
510 | mflo t6 |
||
511 | |||
512 | mCalc: |
||
513 | move a2, $0 |
||
514 | lw t5, 0(t4) |
||
515 | movz a2, a1, t5 |
||
516 | subu t5, t5, a1 |
||
517 | sltu t7, t5, t6 # if ( t5 < t6 ) then ( t7 = 1 ) |
||
518 | subu t5, t5, t6 # t5 = t5 - t6 |
||
519 | sw t5, 0(t4) # 4 bytes of data transfered from address specified by t4 to t5 |
||
520 | or t7, t7, a2 |
||
521 | move a1, t7 |
||
522 | addiu t4, t4, 4 |
||
523 | addiu t3, t3, 4 |
||
524 | bne t3, t2, mMultandSub |
||
525 | mfhi t6 |
||
526 | move a2, $0 |
||
527 | lw t5, 0(t4) |
||
528 | movz a2, a1, t5 |
||
529 | subu t5, t5, a1 |
||
530 | sltu t7, t5, t6 # if ( t5 < t6 ) then ( t7 = 1 ) |
||
531 | subu t5, t5, t6 # t5 = t5 - t6 |
||
532 | sw t5, 0(t4) # 4 bytes of data transfered from address specified by t4 to t5 |
||
533 | or t7, t7, a2 |
||
534 | move a1, t7 |
||
535 | addiu t4, t4, 4 |
||
536 | beqz a1, masDone |
||
537 | |||
538 | mSubBorrow: |
||
539 | subu t7, t4, t9 |
||
540 | beq t7, t8, masDone |
||
541 | lw t7, 0(t4) |
||
542 | addiu t6, t7, -1 |
||
543 | sw t6, 0(t4) |
||
544 | addiu t4, t4, 4 |
||
545 | beq t7, $0, mSubBorrow |
||
546 | nop |
||
547 | |||
548 | masDone: |
||
549 | jr $ra |
||
550 | nop |
||
551 | |||
552 | .end _masBI |
||
553 | |||
554 | |||
555 | /*************************************************************************** |
||
556 | ; Function: void _copyBI() |
||
557 | ; |
||
558 | ; PreCondition: _iA and _iB are loaded with the address of the LSB of each BigInt |
||
559 | ; _xA and _xB are loaded with the address of the MSB of each BigInt |
||
560 | ; |
||
561 | ; Input: A and B, the destination and source |
||
562 | ; |
||
563 | ; Output: A = B |
||
564 | ; |
||
565 | ; Side Effects: None |
||
566 | ; |
||
567 | ; Stack Req: |
||
568 | ; |
||
569 | ; Overview: Copies a value from one BigInt to another |
||
570 | ; |
||
571 | ; Note: Function works |
||
572 | ;***************************************************************************/ |
||
573 | .global _copyBI |
||
574 | |||
575 | .ent _copyBI |
||
576 | |||
577 | _copyBI: |
||
578 | |||
579 | la t0, _xA |
||
580 | lw t0, 0(t0) # Store the address present in __xA & increment it by 4 |
||
581 | |||
582 | la t1, _iA # Store the address present in __iA |
||
583 | addiu t0, t0, 4 |
||
584 | lw t1, 0(t1) |
||
585 | |||
586 | la t2, _xB # Store the address present in __xB & increment it by 4 |
||
587 | lw t2, 0(t2) |
||
588 | |||
589 | la t3, _iB # Store the address present in __iB |
||
590 | addiu t2, t2, 4 |
||
591 | lw t3, 0(t3) |
||
592 | |||
593 | cLoop: |
||
594 | lw t4, 0(t3) |
||
595 | sw t4, 0(t1) |
||
596 | addiu t3, t3, 4 |
||
597 | beq t3, t2, cZeroLoopTest |
||
598 | addiu t1, t1, 4 |
||
599 | bne t1,t0, cLoop |
||
600 | nop |
||
601 | jr $ra |
||
602 | nop |
||
603 | |||
604 | cZeroLoop: |
||
605 | sw $0, 0(t1) |
||
606 | addiu t1, t1, 4 |
||
607 | |||
608 | cZeroLoopTest: |
||
609 | bne t1,t0, cZeroLoop |
||
610 | nop |
||
611 | |||
612 | cend: |
||
613 | jr $ra |
||
614 | nop |
||
615 | |||
616 | .end _copyBI |
||
617 | |||
618 | .set reorder |
||
619 | |||
620 | #endif |
Powered by WebSVN v2.8.3