Re: [AD] Color convertors

["Eric Botcazou" <ebotcazou@xxxxxxxxxx>]

[about the MMX code:]

I can't believe it (2) ;-) You rewrote the MMX code from scratch ! Why ? The
former code was a good performer: here are some tests I conducted with the
former code (Isaac's) vs the new code (basically yours, but I stripped the
whole one pixel/two pixels stuff to keep only the core loop):

K6-III 400 Mhz, MMX enabled, Matrox G200

Win95 OSR2, 800x600x16 desktop:

640x480x8 window:

  SOLID results:       former code        new code

    putpixel()      - 13924            12727
    hline()         - 32795            31432
    vline()         - 24546            23588
    line()          - 509              443
    rectfill()      - 3290             2997
    circle()        - 336              304
    circlefill()    - 604              576
    ellipse()       - 347              301
    ellipsefill()   - 602              586
    arc()           - 583              522
    triangle()      - 620              592

Other functions:

    textout()                    - 2346     2118
    vram->vram blit()            - 5647     5052
    aligned vram->vram blit()    - 5843     5267
    blit() from memory           - 688      610
    aligned blit() from memory   - 691      611
    vram->vram masked_blit()     - 5436     4878
    masked_blit() from memory    - 679      605
    draw_sprite()                - 682      609
    draw_rle_sprite()            - 688      611
    draw_compiled_sprite()       - 568      612
    draw_trans_sprite()          - 679      599
    draw_trans_rle_sprite()      - 683      606
    draw_lit_sprite()            - 677      605
    draw_lit_rle_sprite()        - 686      609



640x480x32 window:

  SOLID results:       former code        new code

    putpixel()      - 11985             12158
    hline()         - 30793             30617
    vline()         - 23243             22545
    line()          - 430               409
    rectfill()      - 2681              2728
    circle()        - 277               274
    circlefill()    - 563               573
    ellipse()       - 279               279
    ellipsefill()   - 565               578
    arc()           - 482               489
    triangle()      - 586               586

Other functions:

    textout()                    - 1944     1950
    vram->vram blit()            - 4700     4642
    aligned vram->vram blit()    - 4866     4850
    blit() from memory           - 571      561
    aligned blit() from memory   - 570      564
    vram->vram masked_blit()     - 4366     4293
    masked_blit() from memory    - 569      563
    draw_sprite()                - 559      550
    draw_rle_sprite()            - 559      556
    draw_compiled_sprite()       - 564      556
    draw_trans_sprite()          - 544      539
    draw_trans_rle_sprite()      - 552      546
    draw_lit_sprite()            - 540      537
    draw_lit_rle_sprite()        - 550      540



Win95 OSR2, 800x600x32 desktop:

640x480x8 window:

  SOLID results:       former code        new code

    putpixel()      - 8340             8118
    hline()         - 26514             26084
    vline()         - 18594             18288
    line()          - 267               236
    rectfill()      - 1739              1575
    circle()        - 173               159
    circlefill()    - 503               498
    ellipse()       - 170               165
    ellipsefill()   - 521               503
    arc()           - 291               291
    triangle()      - 532               523

Other functions:

    textout()                    - 1259     1206
    vram->vram blit()            - 3018     2869
    aligned vram->vram blit()    - 3132     2989
    blit() from memory           - 343      326
    aligned blit() from memory   - 345      327
    vram->vram masked_blit()     - 2947     2832
    masked_blit() from memory    - 341      325
    draw_sprite()                - 343      326
    draw_rle_sprite()            - 343      326
    draw_compiled_sprite()       - 343      326
    draw_trans_sprite()          - 341      322
    draw_trans_rle_sprite()      - 343      324
    draw_lit_sprite()            - 341      326
    draw_lit_rle_sprite()        - 342      324


Afaics there is no significant performance improvement for these routines on
my machine, there is rather a little loss. Given that we finally rejected a
patch for the blit() routine that showed at least some improvements on at
least some machines, I think we should have properly evaluated these
routines before scrapping a stable and relatively fast code.

IMO the only routines that demonstrate a clear performance improvement
are the two new MMX routines (24->32 and 32->24). Here are the results for
the 32->24 routine (after the needed fix):

Win95 OSR2, 800x600x24 desktop:

640x480x32 window:

   SOLID results:   former code    new code
                              (non-MMX)   (MMX)

    putpixel()      - 9297     9500
    hline()         - 27298     27595
    vline()         - 19364     19311
    line()          - 286     290
    rectfill()      - 1868     1994
    circle()        - 192     196
    circlefill()    - 518     547
    ellipse()       - 190     199
    ellipsefill()   - 537     550
    arc()           - 336     349
    triangle()      - 560     538

Other functions:

    textout()                    - 1393     1460
    vram->vram blit()            - 3323     3479
    aligned vram->vram blit()    - 3485     3618
    blit() from memory           - 388     409
    aligned blit() from memory   - 387     409
    vram->vram masked_blit()     - 3166     3279
    masked_blit() from memory    - 388     407
    draw_sprite()                - 385     401
    draw_rle_sprite()            - 386     402
    draw_compiled_sprite()       - 385     406
    draw_trans_sprite()          - 377     396
    draw_trans_rle_sprite()      - 380     398
    draw_lit_sprite()            - 375     395
    draw_lit_rle_sprite()        - 380     397

The improvement seems to be relatively robust on my machine.

---
Eric Botcazou
ebotcazou@xxxxxxxxxx