44 lines
1.6 KiB
NASM
44 lines
1.6 KiB
NASM
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#PURPOSE: This program finds the maximum number of a set of data items.
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#
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#VARIABLES: The registers have the following uses:
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#
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# %edi - Holds the index of the data item being examined
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# %ebx - Largest data item found
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# %eax - Current data item
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#
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# The following memory locations are used:
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#
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# data_items - contains the item data. A 0 is used to terminate the data
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#
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.section .data
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data_items:
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.long 3,67,34,222,45,75,54,34,44,33,22,11,66,0
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.section .text
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.globl _start
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_start:
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movl $0, %edi # move 0 into the index register
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movl data_items(,%edi,4), %eax # load the first byte of data
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movl %eax, %ebx # since this is the first item it
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# is the biggest (duh)
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start_loop: # start the loop
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cmpl $0, %eax # check to see if end value 0
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je loop_exit
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incl %edi # increase index
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movl data_items(,%edi,4),%eax # load the next byte of data
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cmpl %ebx, %eax # compare values
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jle start_loop # jump to the loop beginning if the
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# new value isn't bigger
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movl %eax, %ebx # move the value as the largest
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jmp start_loop # jump to loop beginning
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loop_exit:
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# since %ebx is already the set as the largest value in the data
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# simply return it in the exit system call since it's already %ebx
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movl $1, %eax # 1 tell the kernel to exit
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int $0x80
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