The following warnings occurred:
Warning [2] Undefined property: MyLanguage::$archive_pages - Line: 2 - File: printthread.php(287) : eval()'d code PHP 8.2.18 (Linux)
File Line Function
/inc/class_error.php 153 errorHandler->error
/printthread.php(287) : eval()'d code 2 errorHandler->error_callback
/printthread.php 287 eval
/printthread.php 117 printthread_multipage



Mario Kart Wii Gecko Codes, Cheats, & Hacks
Make it to 10,000 - Printable Version

+- Mario Kart Wii Gecko Codes, Cheats, & Hacks (https://mariokartwii.com)
+-- Forum: Other & Non-Hacking MKW Stuff (https://mariokartwii.com/forumdisplay.php?fid=12)
+--- Forum: General Discussion (https://mariokartwii.com/forumdisplay.php?fid=13)
+--- Thread: Make it to 10,000 (/showthread.php?tid=1338)

Pages: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712


RE: Make it to 10,000 - Fifty - 08-14-2024

So I was doing it wrong all along?


RE: Make it to 10,000 - Cealgair - 08-15-2024

Very much so, yes. (I'm assuming you're a vertebrate, otherwise idk)


RE: Make it to 10,000 - Fifty - 08-15-2024

Date: 14 Aug 2024
Name: Silicosis

DDR 1:51.323


RE: Make it to 10,000 - Vega - 08-15-2024

Voluntary compliance


RE: Make it to 10,000 - Fzerowii - 08-15-2024

You know I work


RE: Make it to 10,000 - Fifty - 08-15-2024

Utilizing the Condition Register

For Advanced ASM Coders



Chapter 1: Intro

Requirements:
  • Understand the basics of using compare and branch instructions
  • Understand binary/bits + Logical Operations

Are your codes ending up with "countless" branches and branch labels? Your codes are in need of some spring cleaning. Sometimes codes that have an excessive amount branches end up "unreadable", making it difficult for others to understand your code or help you debug any errors.



Chapter 2: Condition Register Fundamentals

When you execute any plane jane comparison instruction such as....

Code:
cmpwi r0, 100

...you are actually telling Broadway to run a check and then place the result of said check in Condition Register Field 0.

What is Condition Register Field 0? First thing's first. The register you see in Dolphin that is named "CR" is the Condition Register. It contains the results of previously executed Compare Instructions. Conditional Branch Instructions (i.e. beq) read the data of the Condition Register to determine whether or not a branch route/jump is taken.

The Condition Register contains 7 fields. Field 0 (cr0) thru Field 7 (cr7).

STUVWXYZ

S = cr0
T = cr1
U = cr2
etc etc..

Each field (crF) takes up one DIGIT (half-byte) in the CR. Thus, each crF contains 4 bits of data. You can specify which crF to place the result of the compare instruction in. By default, if no crF is specified in your compare instruction, then cr0 will be used.

Code:
cmpwi r0, 100

is short for...

Code:
cmpwi cr0, r0, 100

If you wish to use cr7 instead of cr0, you would write the instruction like this...

Code:
cmpwi cr7, r0, 100

An important thing that you must keep in mind is that if you make a comparison that is NOT using cr0, you must also specify the crF in the subsequent branch instruction.

Like this...

Code:
cmpwi cr7, r0, 100
beq- cr7, store_data #Notice the specification of cr7 in the instruction

In conclusion, any crF that isn't cr0 must be specified in both compare and branch instructions.



Chapter 3: Condition Register Field Bits and Examining Branch Instructions

Now that you know there are 7 crF's and how to use each one in your comparison + branch instructions, let's cover the crF bits and what each bit represents.

Each crF has 4 bits of data that uses the following structure.
  • bit 0 = Less-Than flag (LT)
  • bit 1 = Greater-Than flag (GT)
  • bit 2 = Equal flag (EQ)
  • bit 3 = Summary Overflow flag (SO)

CR Bit Table
LT GT EQ SO  crfX
0  1  2  3  crf0
4  5  6  7  crf1
8  9 10 11  crf2
12 13 14 15  crf3
16 17 18 19  crf4
20 21 22 23  crf5
24 25 26 27  crf6
28 29 30 31  crf7

Whenever a bit in the crF is high, the condition was true FROM THE MOST RECENT comparison instruction. Whenever a bit was low, the condition was false FROM THE MOST RECENT comparison.

Multiple bits can be flagged high and/or low from a comparison instruction. Now that you understand the crF bits, let's go over what branch instructions actually do.

Code:
bge (branch if greater than or equal) = checks bits 0, if bit is low, branch is taken
bgt (branch if greater than) = checks bit 1, if bit is high, branch is taken
ble (branch if less than or equal) = checks bit 1, if bit is low, branch is taken
blt (branch if less than) = checks bit 0, if it is high, branch is taken
bne (branch if not equal) = checks bit 2, if bit is low, branch is taken
bng (branch if not greater than) = equivalent to ble
bnl (branch if not less than) = equivalent to bge
bns (branch if not summary overflow) = checks bit 3, if bit is low, branch is taken
bso (branch if summary overflow) = checks bit 3, if bit is high, branch is taken

The branch instruction checks the bits of the crF that is specified in the instruction.

Example: 'bge- cr7' checks LT bit of cr7. If low, branch is taken.



Chapter 4: Condition Register specific instructions

Before going into the CR specific instructions, we need to go over its 'format'. The 'format' of a typical CR instruction is this..

crXXX B, B, B #XXX = and, or, andc, orc, nor, xor, eqv

Under this format, you need to specify the exact bit of the entire Condtion Register. The problem with this is that it now becomes a memory game and you have to refer to the earlier CR bit table provided in Chapter 3. Instead of doing that non-sense, you can use this handy formula...

B = 4*crX+ZZ

X = field number (0 thru 7)
ZZ = lt, gt, eq, or so

With this formula, all you need to remember to which Field you want to use and what bit type. So now the easier-to-remember 'format' is this..

crXXX 4*crX+ZZ, 4*crX+ZZ, 4*crX+ZZ

---

CR Based Instructions:
  • Condition Register Logical OR~
    cror crfD, crfA, crfB #crfA bit is logically OR'd with crfB bit. Result is written to crfD bit.
  • Condition Register Logical AND~
    crand crfD, crfA, crfD #crfA bit is logically AND'd with crfB bit. Result is written to crfD bit.
  • Condition Register Logical NOR~
    crnor crfD, crfA, crfD #crfA bit is logically NOR'd with crfB bit. Result is written to crfD bit.
  • Condition Register Logical XOR~
    crxor crfD, crfA, crfD #crfA bit is logically XOR'd with crfB bit. Result is written to crfD bit.
  • Condition Register Logical EQV (XNOR)~
    creqv crfD, crfA, crfD #crfA bit is logically XNOR'd with crfB bit. Result is written to crfD bit. Technically, the instruction does a XOR of crfA with crfD, then this temp result is complemented, then writes that result to crfD.
  • Condition Register Logical AND with Complement~
    crandc crfD, crfA, crfD #crfA bit is logically AND'd with the complemented crfB bit. Result is written to crfD bit.
  • Condition Register Logical OR with Complement~
    crorc crfD, crfA, crfD #crfA bit is logically OR'd with the complemented crfB bit. Result is written to crfD bit.

Simplified Mnemonics:
  • Setting a bit high (set cr0 EQ high)~
    crset 4*cr0+eq #creqv 4*cr0+eq, 4*cr0+eq, 4*cr0+eq; crF bit is XNOR'd with itself and resutl written to same bit spot
  • Setting a bit low (set cr0 EQ low)~
    crclr 4*cr0+eq #crxor 4*cr0+eq, 4*cr0+eq, 4*cr0+eq; crF bit is XOR'd with itself and result written to same bit spot
  • Copy-Pasting (Moving) a bit (copy cr0 EQ bit to cr7 EQ bit's spot)
    crmove 4*cr7+eq, 4*cr0+eq #cror 4*cr7+eq, 4*cr0+eq, 4*cr0+eq; crF bit is Or'd with itself and result writen to crfD
  • Flip a bit (flip cr0 EQ bit and place result in cr7 EQ bit's spot))
    crnot 4*cr7+eq, 4*cr0+eq  #crnor 4*cr0+eq, 4*cr0+eq, 4*cr0+eq; crF bit is NOR'd with itself and result written to crfD

Also, the following instructions may be handy for you...
  • mfcr rD #Contents of the CR is copied to rD
  • mtcr rD #Contents of rD is copied to the CR
  • mcrf crD, crA #Condition Field A is copied to Condition Field D



Chapter 5: Cleaning up some Code

Let's go over some basic examples of some "CR trickery" to help clean up code. Some examples below won't shorten the source at all (will be same compiled length), but the amount of branches (plus label names) are reduced. This is accomplished by using multiple crF's and using Condition Register specific instructions.

Scenario 1:
If r4 = 1 and r10 = r31, then go to 'store_data'. Otherwise, go to 'dont_store'.

Typical Source
Code:
cmpwi r4, 1
bne- dont_store
cmpw r10, r31
beq- store_data

New Source
Code:
cmpwi r4, 1
cmpw cr7, r10, r31
crand 4*cr0+eq, 4*cr0+eq, 4*cr7+eq
beq- store_data

Scenario 2:
If r4 = 1 or r10 = r31, then go to 'store_data'. Otherwise, go to 'dont_store'.

Typical Source
Code:
cmpwi r4, 1
beq- store_data
cmpwi r10, r31
bne- dont_store

New Source
Code:
cmpwi r4, 1
cmpw cr7, r10, r31
cror 4*cr0+eq, 4*cr0+eq, 4*cr7+eq
beq- store_data

Scenario 3:
If r4 = 1 and r10 =/= r31, then go to 'store_data'. Otherwise, end_code

Typical Source
Code:
cmpwi r4, 1
bne- end_code
cmpw r10, r31
bne- store_data

New Source
Code:
cmpwi r4, 1
cmpw cr7, r10, r31
crandc 4*cr0+eq, 4*cr0+eq, 4*cr7+eq
beq- store_data

Scenario 4:
If r4 = 1 or r10 =/= r31, then go to 'store_data'.

Typical Source
Code:
cmpwi r4, 1
beq- store_data
cmpw r10, r31
bne- store_data

New Source
Code:
cmpwi r4, 1
cmpw cr7, r10, r31
crorc 4*cr0+eq, 4*cr0+eq, 4*cr7+eq
beq- store_data

Scenario 5:
If r4 = 1 then r10 must =/= r31, or if r4 =/=1 then r10 must = r31. If all requirments met go to 'store_data'. If not, go to end_code.

Typical Source
Code:
cmpwi r4, 1
bne- make_sure_next_true

#r4 = 1, r10 must =/= r31
cmpw r10, r31
bne- store_data
b end_code

#r4 =/= 1, r10 must = r31
make_sure_next_true:
cmpw r10, r31
beq- store_data

New Source
Code:
cmpwi r4, 1
cmpw cr7, r10, r31
crxor 4*cr0+eq, 4*cr0+eq, 4*cr7+eq
beq- store_data

Scenario 6:
If r4 = 1, then r10 must = r31. However r4 can =/= 1 as long as r10 =/= r31. If all requirements are met go to 'store_data'. If not, go to end_code.

Typical source
Code:
cmpwi r4, 1
bne- make_sure_next_false

#r4 = 1, r10 must = r31
cmpw r10, r31
bne- store_data
b end_code

#r4 =/= 1, r10 must =/= r31
make_sure_next_false:
cmpw r10, r31
bne- store_data

New source
Code:
cmpwi r4, 1
cmpw cr7, r10, r31
creqv 4*cr0+eq, 4*cr0+eq, 4*cr7+eq
beq- store_data



Chapter 6: Final Example

Let's say you have a value in r3 and it must be a valid Memory Address. Meaning a valid mem80, mem81, or mem9 address. If the address is not valid in any way, branch to the LR. An efficient way to write it would be like this (pretend r4 thru r7 are safe)...

Code:
lis r4, 0x8000 #0x80000000
lis r5, 0x817F #0x817FFFFF
ori r5, r5, 0xFFFF
addis r6, r4, 0x1000 #0x90000000
addis r7, r5, 0x1280 #0x93FFFFFF

cmplw r3, r4
cmplw cr5, r3, r5
cmplw cr6, r3, r6
cmplw cr7, r3, r7
cror 4*cr0+eq, 4*cr0+lt, 4*cr7+gt #Check if less than 0x80000000 ***or*** greater than 0x93FFFFFF; place result in cr0
crand 4*cr5+eq, 4*cr5+gt, 4*cr6+lt #Now check if its in between 0x817FFFC0 ***and*** 0x90000000; place result in cr5
cror 4*cr0+eq, 4*cr0+eq, 4*cr5+eq #If *any* of the two above conditions (cr0 and cr5) were true, branch to LR
beqlr-

And that's pretty much it. Happy coding!


RE: Make it to 10,000 - Cealgair - 08-15-2024

"Wow you're tall for a *micro* biologist" -- me yesterday


RE: Make it to 10,000 - Vega - 08-15-2024

omfg....


RE: Make it to 10,000 - Cealgair - 08-15-2024

.....


RE: Make it to 10,000 - Fifty - 08-15-2024

Thewh