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Re: Rep:Re: Rep:Re: [f-cpu] signed cmpl
> Sorry, I misunderstood. But on the other hand, 6 bits aren't much for
> most purposes - you would have to `loadcons*' more often...
>
> >>>Only our gcc expert could answer. So, does 32 to -32 number (or 0 to
> 64) immediat instruction could cover most immediat instructions used by
> gcc ?
> nicO
Because I test majority of things with vsprintf.c from linux kernel
just now it is not too objective. There is 275 immediates used in the
file. Here is usage of constant NOT IN -32...31 range:
13 addi
21 andi
3 cmplei
1 cmplesi
2 ori
33 xor.ori
and these are IN range:
140 addi
23 andi
1 cmplei
13 cmplesi
3 cmplsi
4 nxor.andi
7 ori
4 shiftli
7 xor.ori
So that 202 insns ARE in 6bit range but these was constants 1 and -1
often (addi) - I didn't implemented INC/DEC yet. There was 82 of such.
As conclusion from 275 immediates 120 (202-82) can be coded into
6 bits.
devik
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