RISC-V-Simulator/code.mc at master · dilip640/RISC-V-Simulator · GitHub

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0x0 0x00500513
0x4 0x008000ef
0x8 0x0400006f
0xC 0xff810113
0x10 0x00112223
0x14 0x00a12023
0x18 0xfff50293
0x1c 0x0002d663
0x20 0x00100513
0x24 0x00008067
0x28 0xfff50513
0x2c 0xfe1ff0ef
0x30 0x00810113
0x34 0x00050313
0x38 0x00012503
0x3c 0x00412083
0x40 0x02650533
0x44 0x00008067
-------------------
0x0	0x00600293
0x4	0x01400313
0x8	0x02536233
--------------------
addi x10, x0, 5
jal x1, fact
jal x0 EXIT

fact:
addi x2, x2, -8 #// adjust stack for 2 items
sw x1, 4(x2)#// save the return address
sw x10, 0(x2)#// save the argument n
addi x5, x10, -1 #// x5 = n - 1
bge x5, x0, L1 #// if (n - 1) >= 0, go to L1
addi x10, x0, 1 #// return 1

jalr x0, 0(x1) #// return to caller

L1: addi x10, x10, -1 #// n >= 1: argument gets (n −1)
jal x1, fact #// call fact with (n −1)

addi x2, x2, 8 #// pop 2 items off stack
addi x6, x10, 0 #// return from jal: move result of fact(n -1) to x6:
lw x10, 0(x2) #// restore argument n
lw x1, 4(x2) #// restore the return address

mul x10, x10, x6 #// return n * fact (n −1)
jalr x0, 0(x1) #// return to the caller

EXIT:
----------------------
addi x4 x5 5
addi x3 x4 4
add x9 x3 x4