Ich bin ein Mips Programm zu schreiben Exponenten zu berechnen, aber eine Fehlermeldung erhalten:MIPS: Holadresse nicht auf Wortgrenze 0x400fffff ausgerichtet
Runtime exception at 0x00400158: fetch address not aligned on word boundary 0x400fffff
Irgendwelche Ideen?
Das Problem Linie ist lw $v0, 0($t0) # $v0 = rev_binary[idx]
.data
prompt1: .asciiz "Enter a base: "
prompt2: .asciiz "Enter an exponential: "
b: .word 0
e: .word 0
rev_binary: .word 0
i: .word 0
result: .word 1
.text
main:
la $a0, prompt1 # print prompt1
addi $v0, $0, 4
syscall
addi $v0, $0, 5 # read b
syscall
move $t0, $v0 # $t0 = b
la $a0, prompt2 # print prompt2
addi $v0, $0, 4
syscall
addi $v0, $0, 5 # read e
syscall
move $t1, $v0 # $t1 = e
addi $sp, $sp, -8 # 2 * 4 = 8 bytes
sw $t1, 4($sp)
sw $t0, 0($sp)
jal power
move $a0, $v0
addi $v0, $0, 1
syscall # print the return value
j end
power:
# save $ra and $fp
addi $sp, $sp, -8
sw $ra, 4($sp)
sw $fp, 0($sp)
#copy $sp to $fp
addi $fp, $sp, 0
# allocate local variables
addi $sp, $sp, -20
# save $sp into $fp
move $fp, $sp
#rev_binary = [ 0 ] * e
lw $a0, 32($sp)
sll $a0, $a0, 2 # $a0 = 4 * e(e << 2)
addi $a0, $a0, 4 # $a0 = 4 * e + 4
addi $v0, $0, 9 # $v0 = 9
syscall # allocate memory
sw $v0, 0($sp)
lw $t0, 32($sp) # $t0 = e
sw $t0, 0($v0) #store the size of rev_binary
sw $0, 4($sp)
while0:
# while e != 0
lw $t0, e # $t0 = e
beq $t0, $0, while0_end # break if e == 0
# e_half = e >> 1
lw $t0, 32($sp) # allocate e_half
srl $t1, $t0, 1 # $t1 = $t0 >> 1
sw $t1, 8($sp) # e_half = $t1
# rev_binary[i] = e - 2 * e_half
lw $t0, 8($sp) # $t0 = e_half
sll $t0, $t0, 1 # $t0 = e_half * 2
lw $t1, e # $t1 = e
sub $t0, $t1, $t0 # $t0 = e - e_half * 2
lw $t1, 4($sp) # $t1 = i
sll $t1, $t1, 2
addi $t1, $t1, 4 # $t1 = i * 4 + 4
lw $t2, rev_binary # $t3 = the address of rev_binary
add $t1, $t1, $t2 # $t1 = the address of rev_binary[i]
sw $t0, 0($t1) # rev_binary[i] = $t0
# i += 1
lw $t0, 4($sp) # $t0 = i
addi $t0, $t0, 1 # $t0 += 1
sw $t0, 4($sp) # i = $t0
# e = e_half
lw $t0, 8($sp) # $t0 = e_half
sw $t0, 32($sp) # e = $t0
addi $sp, $sp, 4 # release local variable n_half
j while0
while0_end:
# rev_binary = rev_binary[:i]
lw $t0, 0($sp) # $t0: the address of rev_binary
lw $t1, 4($sp) # $t1 = i
sw $t1, 0($t0) # set the size of rev_binary to i
# result = 1
addi $t0, $0, 1 # $t0 = 1
sw $t0, 12($sp) # result = $t0
# for j in range(i - 1, -1, -1):
addi $sp, $sp, -4 # allocate j
lw $t0, i # $t0 = i
addi $t0, $t0, -1 # $t0 -= 1
sw $t0, 0($sp) # j = $t0 = i - 1
# idx = len(rev_binary) - 1
lw $t0, 4($sp) # $t0 = i = len(rev_binary)
addi $t0, $t0, -1 # $t0 -= 1
sw $t0, 16($sp) # idx = $t0
while1: # while idx >= 0
lw $t0, 16($sp) # idx = $t0
blt $t0, $0, while1_end # break if idx < 0
# result = result * result
lw $t0, 12($sp) # t0 = result
mul $t0, $t0, $t0
sw $t0, 12($sp) # $t0 = result
# if rev_binary[idx]
lw $t0, 16($sp) # $t0 = idx
sll $t0, $t0, 2 # $t0 = idx * 4
addi $t0, $t0, 4 # $t0 = idx * 4 + 4
lw $t1, 0($sp) # $t1 = the address of rev_binary
add $t0, $t1, $t0 # $t0 = the address of rev_binary[idx]
lw $v0, 0($t0) # $v0 = rev_binary[idx]
if:
beq $t0, $0, end_if # end if if (idx == 0)
# result = result * b
lw $t0, 12($sp) # $t0 = result
lw $t1, 28($sp) # $t1 = b
mul $t0, $t0, $t1 # $t0 = $t0 * $t1
sw $t0, 12($sp) # result = $t0
end_if:
# idx = idx - 1
lw $t0, 16($sp) # $t0 = idx
addi $t0, $t0, -1 # $t0 -= 1
sw $t0, 16($sp) # idx = $t0
j while1 # loop
while1_end:
lw $v0, 12($sp) # $v0 = result
lw $t0, 20($sp) # reset old $fp
move $fp, $t0
lw $t0, 24($sp) # reset old $ra
move $ra, $t0
addi $sp, $sp, 36 # release local variables
jr $ra # return
end:
# exit
Sie können ein Wort nicht von einer nicht ausgerichteten Adresse lesen. Die Adresse sieht aus, als wäre sie auch nicht korrekt, sind die Werte wirklich korrekt? Kein falscher Wert vom Stapel gelesen? –