我在使用MIPS完成气泡排序代码时遇到了一些麻烦。我不确定如何解决我得到的异常错误。这些是我在QtSpim中遇到的例外。
在PC = 0x00400064处发生异常
读取的数据/堆栈中的错误地址：0x10040000
在PC = 0x0040003c处发生了异常
读取的数据/堆栈中的错误地址：0x10040000
在PC = 0x00400060处发生异常
数据/堆栈中的错误地址读取：0x10040004
在PC = 0x00400064处发生异常
读取的数据/堆栈中的错误地址：0x10040000
.data
.align 4
Input_data: .word 2, 0, -7, -1, 3, 8, -4, 10
.word -9, -16, 15, 13, 1, 4, -3, 14
.word -8, -10, -15, 6, -13, -5, 9, 12
.word -11, -14, -6, 11, 5, 7, -2, -12
Output_data: .word 0, 0, 0, 0, 0, 0, 0, 0
.word 0, 0, 0, 0, 0, 0, 0, 0
.word 0, 0, 0, 0, 0, 0, 0, 0
.word 0, 0, 0, 0, 0, 0, 0, 0
.text
.globl main
.align 4
main:
la $t0, Input_data # Load address of Input_data into t0
la $t1, Output_data # Load address of Output_data into t1
addu $t2, $t1, 128 # Get address of last word in output data (32 * 4 = 128)
li $s0, 1 # Store index for Input_data
li $s1, 32 # Store index for Output_data
sort_main:
lw $s2, 0($t0) # Load word from Input_data
lw $s3, 4($t1)
ble $s2, $s3, sort_swap # If s2 is less than s3, branch to sort_swap
li $s4, 31 # Set s4 counter to 31
beq $s0, $s4, sort_store # For loop, if the counter is 31, branch to sort_store
addu $t0, $t0, 4 # Increment t0 by 4 bytes to get the next item
addu $s0, $s0, 1 # Increment the index
j sort_main # Jump to sort_main
sort_swap:
sw $s2, 4($t0)
sw $s3, 0($t0)
addu $t0, $t0, 4
addu $s0, $s0, 1
j sort_main
sort_store:
lw $s2, 4($t0)
sw $s2, 0($t2)
subu $t2, $t2, 4
subu $s1, $s1, 1
li $s5, 1
beq $s1, $s5, end
la $t0, Input_data
li $s0, 1
j sort_main
end:
j end
QtSpim：
User Text Segment [00400000]..[00440000]
[00400000] 8fa40000 lw $4, 0($29) ; 183: lw $a0 0($sp) # argc
[00400004] 27a50004 addiu $5, $29, 4 ; 184: addiu $a1 $sp 4 # argv
[00400008] 24a60004 addiu $6, $5, 4 ; 185: addiu $a2 $a1 4 # envp
[0040000c] 00041080 sll $2, $4, 2 ; 186: sll $v0 $a0 2
[00400010] 00c23021 addu $6, $6, $2 ; 187: addu $a2 $a2 $v0
[00400014] 0c100009 jal 0x00400024 [main] ; 188: jal main
[00400018] 00000000 nop ; 189: nop
[0040001c] 3402000a ori $2, $0, 10 ; 191: li $v0 10
[00400020] 0000000c syscall ; 192: syscall # syscall 10 (exit)
[00400024] 3c081001 lui $8, 4097 [Input_data]; 19: la $t0, Input_data # Load address of Input_data into t0
[00400028] 3c011001 lui $1, 4097 [Output_data]; 20: la $t1, Output_data # Load address of Output_data into t1
[0040002c] 34290080 ori $9, $1, 128 [Output_data]
[00400030] 252a0080 addiu $10, $9, 128 ; 21: addu $t2, $t1, 128 # Get address of last word in output data (32 * 4 = 128)
[00400034] 34100001 ori $16, $0, 1 ; 22: li $s0, 1 # Store index for Input_data
[00400038] 34110020 ori $17, $0, 32 ; 23: li $s1, 32 # Store index for Output_data
[0040003c] 8d120000 lw $18, 0($8) ; 26: lw $s2, 0($t0) # Load word from Input_data
[00400040] 8d330004 lw $19, 4($9) ; 27: lw $s3, 4($t1)
[00400044] 0272082a slt $1, $19, $18 ; 28: ble $s2, $s3, sort_swap # If s2 is less than s3, branch to sort_swap
[00400048] 10200006 beq $1, $0, 24 [sort_swap-0x00400048]
[0040004c] 3414001f ori $20, $0, 31 ; 29: li $s4, 31 # Set s4 counter to 31
[00400050] 12140009 beq $16, $20, 36 [sort_store-0x00400050]
[00400054] 25080004 addiu $8, $8, 4 ; 31: addu $t0, $t0, 4 # Increment t0 by 4 bytes to get the next item
[00400058] 26100001 addiu $16, $16, 1 ; 32: addu $s0, $s0, 1 # Increment the index
[0040005c] 0810000f j 0x0040003c [sort_main] ; 33: j sort_main # Jump to sort_main
[00400060] ad120004 sw $18, 4($8) ; 36: sw $s2, 4($t0)
[00400064] ad130000 sw $19, 0($8) ; 37: sw $s3, 0($t0)
[00400068] 25080004 addiu $8, $8, 4 ; 38: addu $t0, $t0, 4
[0040006c] 26100001 addiu $16, $16, 1 ; 39: addu $s0, $s0, 1
[00400070] 0810000f j 0x0040003c [sort_main] ; 40: j sort_main
[00400074] 8d120004 lw $18, 4($8) ; 43: lw $s2, 4($t0)
[00400078] ad520000 sw $18, 0($10) ; 44: sw $s2, 0($t2)
[0040007c] 254afffc addiu $10, $10, -4 ; 45: subu $t2, $t2, 4
[00400080] 2631ffff addiu $17, $17, -1 ; 46: subu $s1, $s1, 1
[00400084] 34150001 ori $21, $0, 1 ; 47: li $s5, 1
[00400088] 12350004 beq $17, $21, 16 [end-0x00400088]
[0040008c] 3c081001 lui $8, 4097 [Input_data]; 49: la $t0, Input_data
[00400090] 34100001 ori $16, $0, 1 ; 50: li $s0, 1
[00400094] 0810000f j 0x0040003c [sort_main] ; 51: j sort_main
[00400098] 08100026 j 0x00400098 [end] ; 54: j end
Kernel Text Segment [80000000]..[80010000]
[80000180] 0001d821 addu $27, $0, $1 ; 90: move $k1 $at # Save $at
[80000184] 3c019000 lui $1, -28672 ; 92: sw $v0 s1 # Not re-entrant and we can't trust $sp
[80000188] ac220200 sw $2, 512($1)
[8000018c] 3c019000 lui $1, -28672 ; 93: sw $a0 s2 # But we need to use these registers
[80000190] ac240204 sw $4, 516($1)
[80000194] 401a6800 mfc0 $26, $13 ; 95: mfc0 $k0 $13 # Cause register
[80000198] 001a2082 srl $4, $26, 2 ; 96: srl $a0 $k0 2 # Extract ExcCode Field
[8000019c] 3084001f andi $4, $4, 31 ; 97: andi $a0 $a0 0x1f
[800001a0] 34020004 ori $2, $0, 4 ; 101: li $v0 4 # syscall 4 (print_str)
[800001a4] 3c049000 lui $4, -28672 [__m1_] ; 102: la $a0 __m1_
[800001a8] 0000000c syscall ; 103: syscall
[800001ac] 34020001 ori $2, $0, 1 ; 105: li $v0 1 # syscall 1 (print_int)
[800001b0] 001a2082 srl $4, $26, 2 ; 106: srl $a0 $k0 2 # Extract ExcCode Field
[800001b4] 3084001f andi $4, $4, 31 ; 107: andi $a0 $a0 0x1f
[800001b8] 0000000c syscall ; 108: syscall
[800001bc] 34020004 ori $2, $0, 4 ; 110: li $v0 4 # syscall 4 (print_str)
[800001c0] 3344003c andi $4, $26, 60 ; 111: andi $a0 $k0 0x3c
[800001c4] 3c019000 lui $1, -28672 ; 112: lw $a0 __excp($a0)
[800001c8] 00240821 addu $1, $1, $4
[800001cc] 8c240180 lw $4, 384($1)
[800001d0] 00000000 nop ; 113: nop
[800001d4] 0000000c syscall ; 114: syscall
[800001d8] 34010018 ori $1, $0, 24 ; 116: bne $k0 0x18 ok_pc # Bad PC exception requires special checks
[800001dc] 143a0008 bne $1, $26, 32 [ok_pc-0x800001dc]
[800001e0] 00000000 nop ; 117: nop
[800001e4] 40047000 mfc0 $4, $14 ; 119: mfc0 $a0 $14 # EPC
[800001e8] 30840003 andi $4, $4, 3 ; 120: andi $a0 $a0 0x3 # Is EPC word-aligned?
[800001ec] 10040004 beq $0, $4, 16 [ok_pc-0x800001ec]
[800001f0] 00000000 nop ; 122: nop
[800001f4] 3402000a ori $2, $0, 10 ; 124: li $v0 10 # Exit on really bad PC
[800001f8] 0000000c syscall ; 125: syscall
[800001fc] 34020004 ori $2, $0, 4 ; 128: li $v0 4 # syscall 4 (print_str)
[80000200] 3c019000 lui $1, -28672 [__m2_] ; 129: la $a0 __m2_
[80000204] 3424000d ori $4, $1, 13 [__m2_]
[80000208] 0000000c syscall ; 130: syscall
[8000020c] 001a2082 srl $4, $26, 2 ; 132: srl $a0 $k0 2 # Extract ExcCode Field
[80000210] 3084001f andi $4, $4, 31 ; 133: andi $a0 $a0 0x1f
[80000214] 14040002 bne $0, $4, 8 [ret-0x80000214]; 134: bne $a0 0 ret # 0 means exception was an interrupt
[80000218] 00000000 nop ; 135: nop
[8000021c] 401a7000 mfc0 $26, $14 ; 145: mfc0 $k0 $14 # Bump EPC register
[80000220] 275a0004 addiu $26, $26, 4 ; 146: addiu $k0 $k0 4 # Skip faulting instruction
[80000224] 409a7000 mtc0 $26, $14 ; 148: mtc0 $k0 $14
[80000228] 3c019000 lui $1, -28672 ; 153: lw $v0 s1 # Restore other registers
[8000022c] 8c220200 lw $2, 512($1)
[80000230] 3c019000 lui $1, -28672 ; 154: lw $a0 s2
[80000234] 8c240204 lw $4, 516($1)
[80000238] 001b0821 addu $1, $0, $27 ; 157: move $at $k1 # Restore $at
[8000023c] 40806800 mtc0 $0, $13 ; 160: mtc0 $0 $13 # Clear Cause register
[80000240] 401a6000 mfc0 $26, $12 ; 162: mfc0 $k0 $12 # Set Status register
[80000244] 375a0001 ori $26, $26, 1 ; 163: ori $k0 0x1 # Interrupts enabled
[80000248] 409a6000 mtc0 $26, $12 ; 164: mtc0 $k0 $12
[8000024c] 42000018 eret ; 167: eret
非常感谢您的帮助。