procmgmt.asm

<虚拟机的设计与实现>一书中hec虚拟机的源代码

.PB main
.PV filename1  -16
.PV filename2  -32
.PV buffer     -512

#allocate local storage
PUSHQ $FP
MOV $FP,$SP
LQI $R7,512
SUB $SP,$SP,$R7

#populate filename1 = xcalc
LAI $R10,$FP,filename1
MOV $R11,$R10
LBI $R2,1

LBI $R1,'x'
SB  $R1,$R10
ADD $R10,$R10,$R2

LBI $R1,'c'
SB  $R1,$R10
ADD $R10,$R10,$R2

LBI $R1,'a'
SB  $R1,$R10
ADD $R10,$R10,$R2

LBI $R1,'l'
SB  $R1,$R10
ADD $R10,$R10,$R2

LBI $R1,'c'
SB  $R1,$R10
ADD $R10,$R10,$R2

LBI $R1,0
SB  $R1,$R10

#populate local filename2 = free
LAI $R10,$FP,filename2
MOV $R12,$R10
LBI $R2,1

LBI $R1,'f'
SB  $R1,$R10
ADD $R10,$R10,$R2

LBI $R1,'r'
SB  $R1,$R10
ADD $R10,$R10,$R2

LBI $R1,'e'
SB  $R1,$R10
ADD $R10,$R10,$R2

LBI $R1,'e'
SB  $R1,$R10
ADD $R10,$R10,$R2

LBI $R1,0
SB  $R1,$R10

#spawn xcalc
LBI $R1,0
LBI $R3,0
MOV $R2,$R11
INT 2

#wait for xcalc to die, then print return code
MOV $R2,$R4
LBI $R1,1
INT 2

MOV $R2,$R3
LBI $R1,20
INT 0

LQI $R2,10
LQI $R1,16
INT 0
LQI $R2,13
LQI $R1,16
INT 0

#spawn xcalc again using different function
LBI $R1,2
MOV $R2,$R11
INT 2

MOV $R2,$R3
LBI $R1,20
INT 0

LQI $R2,10
LQI $R1,16
INT 0
LQI $R2,13
LQI $R1,16
INT 0

#call free and print output
LBI $R1,3
MOV $R2,$R12
LAI $R3,$FP,buffer
LQI $R4,512
INT 2

LAI $R3,$FP,buffer
MOV $R2,$R3
LBI $R1,18
INT 0

LQI $R2,10
LQI $R1,16
INT 0
LQI $R2,13
LQI $R1,16
INT 0

#reclaim local storage
MOV $SP,$FP
POPQ $FP

HALT
.PE