mips associative floating point -

okay testing have code

    .data     # shows can use .word , directly encode value in hex     # if choose num1:   .word 0x3f800000 num2:   .float 1234.567   num3: .float 45.67834 num4: .float 0.0004 result: .word 0 string: .asciiz "\n"      .text main:     la $t0, num1     lwc1 $f2, 4($t0)     lwc1 $f4, 8($t0)     lwc1 $f6, 12($t0)       # print out values of summands      li $v0, 2     mov.s $f12, $f2     syscall      li $v0, 4     la $a0, string     syscall      li $v0, 2     mov.s $f12, $f4     syscall      li $v0, 4     la $a0, string     syscall     li $v0, 4     la $a0, string     syscall      # actual addition      add.s $f12, $f2, $f6     add.s $f12, $f12, $f4       # transfer value floating point reg integer reg      swc1 $f12, 8($t0)     lw $s0, 8($t0)      # @ point, $f12 holds sum, , $s0 holds sum can     # read in hexadecimal      li $v0, 2     syscall     li $v0, 4     la $a0, string     syscall      # jr crashes mars     # jr $ra 

i have this

    add.s $f12, $f2, $f6     add.s $f12, $f12, $f4 

i tried swapping order say

    add.s $f12, $f4, $f6     add.s $f12, $f12, $f2 

but result same

i checked wikipedia examples of floating point additions arent same, comes 1280.2457

http://en.wikipedia.org/wiki/floating_point

they had happen:

 = 1234.567, b = 45.67834, c = 0.0004  (a + b) + c:      1234.567   (a)    +   45.67834 (b)    ____________      1280.24534   rounds   1280.245     1280.245  (a + b)    +   0.0004 (c)    ____________     1280.2454   rounds   1280.245  <--- (a + b) + c  + (b + c):    45.67834 (b)  +  0.0004  (c)  ____________    45.67874    1234.567   (a)  +   45.67874 (b + c)  ____________    1280.24574   rounds   1280.246 <--- + (b + c) 

didn't hapepn me works values try

nm, got it

a=0.00004 b=45.67840 c=1234.567