Mit6.004-lab06-Procedures And Stacks

一、 BETA ISA

A：0、1、2、3、0xc
B：0x2000、0xEDEDEDED、0xFEDEDEDE、0x2004、110000 00000 11111 0010 0000 0000 0000（0xc01f2000）
C：0x87654321、1、0x87654320、0x14、011101 11111 00001 0000 0000 0000 0010(0x77e10002)
D：17、0、32、no instructions need to be changed
E：4、110000 00000 00000 0000 0000 0000 0000（0xC0000000）

二、 快速排序

实现代码

	p_array=R2          // base address of array (arg 0)
    p_left=R3
    p_right=R4
    p_pivotIndex=R5     // Corresponds to PivotIndex in C program
    p_pivotValue=R6
    p_storeIndex=R7
partition:		
        PUSH(LP)
        PUSH(BP)
        MOVE(SP, BP)
		PUSH(R1)
		PUSH(R2)
		PUSH(R3)
		PUSH(R4)
		PUSH(R5)
		PUSH(R6)
		PUSH(R7)
		PUSH(R8)
		PUSH(R9)
		
		LD(BP, -12, p_array)
		LD(BP, -16, p_left)
		LD(BP, -20, p_right)
		ADD(p_left, p_right, p_pivotIndex)
		SHRC(p_pivotIndex, 1, p_pivotIndex)
		MULC(p_pivotIndex, 4, R9)
		ADD(p_array, R9, R9)		
		LD(R9, 0, p_pivotValue)
		MULC(p_right, 4, R9)
		ADD(p_array, R9, R9)
		LD(R9, 0, R7)
		MULC(p_pivotIndex, 4, R9)
		ADD(p_array, R9, R9)
		ST(R7, 0, R9)
		MOVE(p_left, p_storeIndex)
START:	ADDC(p_left, 1, p_left)
		CMPLE(p_left, p_right, R8)
		BF(R8, AFTER)
		MULC(p_left, 4, R9)
		ADDC(R9, -4, R9)
		ADD(p_array, R9, R9)
		LD(R9, 0, R8)		
		CMPLE(R8, p_pivotValue, R1)
		BF(R1, START)
		MULC(p_storeIndex, 4, R9)
		ADD(p_array, R9, R9)
		LD(R9, 0, R1)
		MULC(p_left, 4, R9)
		ADDC(R9, -4, R9)
		ADD(p_array, R9, R9)
		ST(R1, 0, R9)
		MULC(p_storeIndex, 4, R9)
		ADD(p_array, R9, R9)
		ST(R8, 0, R9)		
		ADDC(p_storeIndex, 1, p_storeIndex)
		BR(START)
AFTER:  MULC(p_storeIndex, 4, R9)
		ADD(p_array, R9, R9)
		LD(R9, 0, R8)
		MULC(p_right, 4, R9)
		ADD(p_array, R9, R9)
		ST(R8, 0, R9)
		MULC(p_storeIndex, 4, R9)
		ADD(p_array, R9, R9)
		ST(p_pivotValue, 0, R9)
		MOVE(p_storeIndex, R0)
        POP(R9)
		POP(R8)
		POP(R7)
		POP(R6)
		POP(R5)
		POP(R4)
		POP(R3)
		POP(R2)
		POP(R1)
		
		MOVE(BP, SP)
        POP(BP)
        POP(LP)
        JMP(LP)

quicksort:
        PUSH(LP)
        PUSH(BP)
        MOVE(SP, BP)
		PUSH(R1)
		PUSH(R2)
		PUSH(R3)
		PUSH(R4)
		
		LD(BP, -12, R1)
		LD(BP, -16, R2)
		LD(BP, -20, R3)
		.breakpoint
		CMPLT(R2, R3, R4)
		BF(R4, END)
		PUSH(R3)
		PUSH(R2)
		PUSH(R1)
		BR(partition, LP)
		DEALLOCATE(3)
		.breakpoint
		ADDC(R0, -1, R4)
		PUSH(R4)
		PUSH(R2)
		PUSH(R1)
		BR(quicksort, LP)
		DEALLOCATE(3)
		
		PUSH(R3)
		ADDC(R0, 1, R4)
		PUSH(R4)
		PUSH(R1)
		BR(quicksort, LP)
		DEALLOCATE(3)
		
END:	POP(R4)
		POP(R3)
		POP(R2)
		POP(R1)
        MOVE(BP, SP)
        POP(BP)
        POP(LP)
        JMP(LP)

A：0x14
B：0、-1
C：0xa
D：first (smaller elements)
E：0、4
F：5