所以我正在尝试用MIPS汇编代码编写程序,以帮助我更好地理解浮点加法的工作原理。我编写了一个程序,它从用户那里获得两个输入,并使用任何浮点指令添加它们,除了mtc1和mfc1(用于输入和输出)。我的代码有错误,因为当我添加1 + 2时,我得到2.74804688。我仍在尝试调试代码,但似乎无法掌握问题。如果有人可以提供帮助,我将非常感激。
这是我的代码(不包括用户输入......第一个浮点值在$ s0中,第二个在$ s1中)
#Integer implementation of floating-point addition
#Initialize variables
add $s0,$t0,$zero #first integer value
add $s1,$t1,$zero #second integer value
add $s2,$zero,$zero #initialize sum variable to 0
add $t3,$zero,$zero #initialize SUM OF SIGNIFICANDS value to 0
#get EXPONENT from values
sll $s5,$s0,1 #getting the exponent value
srl $s5,$s5,24 #$s5 = first value EXPONENT
sll $s6,$s1,1 #getting the exponent value
srl $s6,$s6,24 #$s6 = second value EXPONENT
#get SIGN from values
srl $s3,$s0,31 #$s3 = first value SIGN
srl $s4,$s1,31 #$s4 = second value SIGN
#get FRACTION from values
sll $s7,$s0,9
srl $s7,$s0,9 #$s7 = first value FRACTION
sll $t8,$s1,9
srl $t8,$s1,9 #$t8 = second value FRACTION
#compare the exponents of the two numbers
compareExp: ######################
beq $s5,$s6, addSig
blt $s5,$s6, shift1 #if first < second, go to shift1
blt $s6,$s5, shift2 #if second < first, go to shift2
j compareExp
shift1: #shift the smaller number to the right
srl $s7,$s7,1 #shift to the right 1
addi $s5,$s5,1
j compareExp
shift2: #shift the smaller number to the right
#srl $s0,$s0,1 #shift to the right 1
#j compareExp
srl $t8,$t8,1 #shift to the right 1
addi $s6,$s6,1
j compareExp
addSig:
add $t3,$s7,$t8 #Add the SIGNIFICANDS
li $v0, 4
la $a0, sum
syscall
li $v0, 1
move $a0, $t3
syscall
j result
result:
li $v0, 4
la $a0, newline
syscall
sll $t4,$s3,31 #SIGN
#FRACTION
sll $t5,$s6,23 #EXPONENT
add $t6,$t4,$t5
add $t6,$t6,$t3
li $v0, 4
la $a0, sum2
syscall
li $v0, 1
move $a0, $t6
syscall
li $v0, 4
la $a0, newline
syscall
li $v0, 4
la $a0, sum2
syscall
li $v0,2
mtc1 $t6,$f12
syscall
jr $31
# END OF PROGRAM