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Код: Выделить всё

   a(z1);
  da:   60 91 64 00    lds   r22, 0x0064
  de:   ce 01          movw   r24, r28
  e0:   45 96          adiw   r24, 0x15   ; 21
  e2:   70 e0          ldi   r23, 0x00   ; 0
  e4:   bc df          rcall   .-136       ; 0x5e <a>
   z32+=z1;
  e6:   20 91 64 00    lds   r18, 0x0064
  ea:   80 91 7c 00    lds   r24, 0x007C
  ee:   90 91 7d 00    lds   r25, 0x007D
  f2:   a0 91 7e 00    lds   r26, 0x007E
  f6:   b0 91 7f 00    lds   r27, 0x007F
  fa:   82 0f          add   r24, r18
  fc:   91 1d          adc   r25, r1
  fe:   a1 1d          adc   r26, r1
100:   b1 1d          adc   r27, r1
102:   80 93 7c 00    sts   0x007C, r24
106:   90 93 7d 00    sts   0x007D, r25
10a:   a0 93 7e 00    sts   0x007E, r26
10e:   b0 93 7f 00    sts   0x007F, r27



• Fixed registers (r0, r1):
Never allocated by gcc for local data, but often used for fixed purposes:
r0 - temporary register, can be clobbered by any C code (except interrupt handlers
which save it), may be used to remember something for a while within one piece
of assembler code
r1 - assumed to be always zero in any C code, may be used to remember some-
thing for a while within one piece of assembler code, but must then be cleared
after use (clr r1). This includes any use of the [f]mul[s[u]] instructions,
which return their result in r1:r0. Interrupt handlers save and clear r1 on entry,
and restore r1 on exit (in case it was non-zero).