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dev_geral:assembly:numeros_fibonacci

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20 números da série de Fibonacci

Este código em assembly vai mostrar os 20 primeiros números da série de Fibonacci

# Compute/print first ten Fibonacci numbers 
      .data
array:.word    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
blank:.asciiz  " "          
head: .asciiz  "The first 20 Fibonacci numbers are:n"
      .text
      la   $a0, array       # load array base address
      li   $a1, 20          # hardcode array size 20
      li   $t0, 1           # 1 is F(0), first Fib. number
      sw   $t0, 0($a0)      # F[0] = 1
      sw   $t0, 4($a0)      # F[1] = F[0] = 1
      add  $t0, $zero, $a0  # copy of array address
      addi $t1, $a1, -2     # loop counter;(size-2) repetitions
loop: lw   $t3, 0($t0)      # Get value from array F[n] 
      lw   $t4, 4($t0)      # Get value from array F[n+1]
      add  $t2, $t3, $t4    # $t2 = F[n] + F[n+1]
      sw   $t2, 8($t0)      # Store F[n+2] = F[n] + F[n+1]
      addi $t0, $t0, 4      # increment address of Fib. Number
      addi $t1, $t1, -1     # decrement loop counter
      bgtz $t1, loop        # repeat if not finished yet.
      jal  out              # call print routine. 
      li   $v0, 10          # system call for exit
      syscall               # we are out of here.      
 
#########  subroutine to print the 20 numbers. 
 
out:  add  $t0, $zero, $a0  # starting address of array
      add  $t1, $zero, $a1  # initialize loop counter
      la   $a0, head        # load address of heading for syscall
      li   $v0, 4           # specify Print String service
      syscall               # print the heading
print:lw   $a0, 0($t0)      # load fibonacci number for syscall
      li   $v0, 1           # specify Print Integer service
      syscall               # print fibonacci number
      la   $a0, blank       # load address of spacer for syscall
      li   $v0, 4           # specify Print String service
      syscall               # print spacer string
      addi $t0, $t0, 4      # increment array address
      addi $t1, $t1, -1     # decrement loop counter
      bgtz $t1, print       # repeat if not finished
      jr   $ra              # return
dev_geral/assembly/numeros_fibonacci.txt · Esta página foi modificada pela última vez em: 2014/09/02 12:39 (Edição externa)