1k Trinity no ordinals

[ninogenio]

ahh now i see where you had trouble removing crt jim!

thats nuts that the compiler takes that much control. cheers for theinfo guys ill maybe try and do a 1k now

[taj]

Cool. Are your working fellows also interesting in scene and creating tiny codes The most ppl
I know doesn't even know that the scene exists and that there are size competitions like 1KB / 4KB.

Wll Im their Director so I gave them some lunch time talks on it and now they are quite interested. Wierdly, I left the scene and now my company wants me to write a demo for a set top box for a show in two weeks so I'm now
coding all day a demo for the silliest hardware in town. Weird world.

Chris

[taj]

Also, VC2005 sees this loop...

Code Select Expand


char *dst = ...;
size_t size = ...;
int val = ...;
while (size--)
  *dst++ = val;

...and variations on it, and automatically optimizes that to

Code Select Expand


memset(dst, val, size);

which isn't very useful when you haven't linked in the C runtime!  Couldn't find an option to turn that off.  VC2005 likes generating these intrinsics wherever it can.

Jim

Yeah I faced that and got mad at the compiler. The solution is simple though, write the lopp backwards. Yes I know its more bytes but it works, the compiler is dumb enoyugh it cant spot the memcpy if the loop counts up ;-). Well VC++ Express version anyway.

Chris

[Jim]

The way I fixed it was to guarantee the size to be filled was a multiple of 4 (since it was 32bit pixels)
So I made it

Code Select Expand


char *dst = ...;
int *idst = (unsigned int *)dst;
size_t size = ...;
int val = ...;
val *= 0x01010101;
size>>=2;
while (size--)
  *idst++ = val;

Like you say, it's very stupid and it doesn't recognise that as 'rep stosd'.

Jim

[benny!]

Wll Im their Director so I gave them some lunch time talks on it and now they are quite interested.
Wierdly, I left the scene and now my company wants me to write a demo for a set top box for a
show in two weeks so I'm now coding all day a demo for the silliest hardware in town. Weird world.
...

Thats the weird way of life indeed, Chris ... but with you they have the best man around to do
this job IMHO.


@taj+jim:
Neat tricks you talk about atm. Too much for my little brain right now. But very interesting !!!