World: r3wp

for example, if i want to test the 7th bit , i do
and  var 128
ift [ do the job]

instead of doing
and var 128
eq.i var 128
ift [ do the job]

Whae does SETT do here?

sett ?

you mean

It sets the T flag based on the contents of a variable. I think it 
sets T to false if the var has 0, none or false, and sets T to true 
otherwise.

and var 128
sett var
ift [do the job]

Yeah.

Try it. My memory of the behavior of SETT on 0 is a little sparse.

i don't see any gain

It would be faster than a compare.

i use 3 instructions to test a bit in all cases

should have:
bit 7 [do the job]

:-)

missing the operand

I'm curious, did you check SETT to see if the value 0 sets the T 
flag to false?

no sorry , i test now

it works

anyway it's not really a problem, i never perform such tests

Cool. So SETT can replace ZERO? and NONE?, which otherwise don't 
have rebcode equivalents.

Or rather NOT ZERO? and NOT NONE?, but the effect is the same.

i don't understand usage of ext8 and ext16

perhaps, they should be usefull for me

Sign extension, so that you can use signed arithmetic on integers 
that contain values retrieved from 8 or 16 bit data.

It's so you don't have to do arithmetic on bytes.

hum i see

i think i should replace this:

gt.i decal 127 ift [sub.i decal 256]

by this: ext8 decal

eureka !!!!

Looks like.

thi code is the macro i use the most

*is in the macro

I wonder how much other code generated by your macros could be optimized...

not as much as that

i hope

but surely some of them

Perhaps some of those and x 255 operations could be put off until 
the value is written to memory.

While the values are in the registers, who cares what precision they 
are internally.

It would make the C flag easy to keep track of. Perhaps some of the 
multibyte operation sequences could be combined.

hum

Where it matters you could replicate the overflow behavior on purpose.

but you see, the 8bit registers are often combined into 16bits registers, 
so i should perform AND 255 before to translate them into 16 bit, 
i'm not sure  there is a real gain

That combination of 8-bit values into 16-bit registers has got to 
be a common code pattern. Are the 16-bit operations distinct from 
the 8-bit ones? This is the kind of code pattern that you could combine 
and optimize. Internally, do you need to have the 16-bit registers 
be a combination of the 8, or could they be seperate and have their 
values transfered over if it would be faster?

Are the 16-bit values loaded in one statement or two?

Need there be a difference?

It's what the modern processor designers call register renaming :)

sorry,
disconnected

not sure to understand what u mean

I would have to read your Z80 manual to be sure, but it seems to 
me that these 16-bit operations seem to be great candidates for opcode 
combining. It may even be a good idea to have the 16-bit registers 
be seperate variables internally.