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			574 lines
		
	
	
		
			16 KiB
		
	
	
	
		
			Python
		
	
	
		
			Executable File
		
	
	
	
	
			
		
		
	
	
			574 lines
		
	
	
		
			16 KiB
		
	
	
	
		
			Python
		
	
	
		
			Executable File
		
	
	
	
	
#!/usr/bin/python3
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##################################
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# testgen-CAUSE.py (new)
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#
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# dottolia@hmc.edu 1 Mar 2021
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#
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# Generate directed and random test vectors for RISC-V Design Validation.
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#
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#
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##################################
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# DOCUMENTATION:
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#
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# The most up-to-date comments explaining what everything
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# does and the layout of the privileged tests
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# can be found in testgen-TVAL.py. This and
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# other files do not have as many comments
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#
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###################################
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##################################
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# libraries
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##################################
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from datetime import datetime
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from random import randint 
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from random import seed
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from random import getrandbits
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##################################
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# functions
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##################################
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#For instruction-fetch access or page-fault exceptions on systems with variable-length instructions, mtval will contain the virtual address of the portion of the instruction that caused the fault while mepc will point to the beginning of the instruction.
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def randRegs():
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  reg1 = randint(1,20)
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  reg2 = randint(1,20)
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  reg3 = randint(1,20)
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  if (reg1 == 6 or reg2 == 6 or reg3 == 6 or reg1 == reg2):
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    return randRegs()
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  else:
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      return str(reg1), str(reg2), str(reg3)
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def writeVectors(storecmd, returningInstruction):
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  global testnum
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  if testMode == "m":
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    if fromMode == "m":
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      expectedCode = 7 if fromMode == "m" else 5
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      clintAddr = "0x2004000"
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      writeTest(storecmd, f, r, f"""
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        li x1, 0x8
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        csrrs x0, {fromMode}status, x1
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        la x18, {clintAddr}
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        {loadcmd} x11, 0(x18)
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        li x1, 0x3fffffffffffffff
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        {storecmd} x1, 0(x18)
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        li x1, 0x80
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        csrrs x0, {fromMode}ie, x1
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        {storecmd} x0, 0(x18)
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      """, True, expectedCode, f"""
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        li x1, 0x80
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        csrrc x0, {fromMode}ie, x1
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        li x1, 0x8
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        csrrc x0, {fromMode}status, x1
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        la x18, {clintAddr}
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        li x1, -1
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        {storecmd} x1, 0(x18)
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      """)
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    # Page 6 of unpriviledged spec
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  # For both CSRRS and CSRRC, if rs1=x0, then the instruction will not write to the CSR at all, and so shall not cause any of the side effects
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  # User Software Interrupt: True, 0
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  # Supervisor Software Interrupt: True, 1
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  # Machine Software Interrupt: True, 2
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  # When running run.sh CAUSE -c, everything works, but begin_signature doesn't appear
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  # 0x2000000 in wally
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  # writeTest(storecmd, f, r, f"""
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  #   la x10, 0x2000000 #clint
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  #   li x1, 42
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  #   sw x1, 0(x10)
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  # """, True, 2, "m", f"""
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  #   lw x0, 0(x10)
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  # """)
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  # User Timer Interrupt: True, 4
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  # Supervior timer interrupt: True, 5
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  # Machine timer interrupt: True, 7
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  # if fromMode == "m":
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  #   clintAddr = "0x2004000"
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  #   writeTest(storecmd, f, r, f"""
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  #     # li x1, 0x8
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  #     # csrrs x0, mstatus, x1
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  #     # li x1, 0x80
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  #     # csrrs x0, mie, x1
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  #     # la x18, {clintAddr}
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  #     # lw x11, 0(x18)
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  #     # lw x12, 4(x18)
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  #     # li x1, 1
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  #     # {storecmd} x1, 0(x18)
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  #     nop
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  #     sub x1, x2, x3
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  #     sub x2, x3, x4
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  #     sub x3, x4, x5
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  #     nop
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  #     nop
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  #     nop
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  #     nop
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  #     nop
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  #     nop
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  #     nop
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  #     nop
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  #     nop
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  #     nop
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  #     nop
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  #     nop
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  #     nop
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  #     nop
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  #     nop
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  #     nop
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  #   """, True, 7, f"""
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  #     # la x18, {clintAddr}
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  #     # {storecmd} x11, 0(x18)
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  #   """)
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  #writeTest(storecmd, f, r, f"""
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  #  li x2, 0x0
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#
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  #   li x4, 0x80
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  #   csrrs x0, mie, x4
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  #   la x2, 0x2004000
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  #   li x3, 0x0
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  #   lw x5, 0(x2)
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  #   sd x3, 0(x2)
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  #   wfi
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  # """, True, 7, "m", f"""
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  #   t
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  # """)
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  # writeTest(storecmd, f, r, f"""
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  #   csrr x18, mstatus
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  #   # csrsi mstatus, 0b11111
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  #   csrr x19, mie
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  #   li x17, 0b1111111111111
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  #   # csrs mie, x17
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  #   la x10, 0x2004000 #clint timer
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  #   li x1, 0
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  #   lw x11, 0(x10)
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  #   lw x12, 4(x10)
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  #   {storecmd} x0, 0(x10)
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  #   {storecmd} x0, 4(x10)
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  # """, True, 7, "m", f"""
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  #   {storecmd} x11, 0(x10)
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  #   {storecmd} x12, 4(x10)
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  #   csrw mstatus, x18
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  #   csrw mie, x19
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  # """)
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  # User external input: True, 8
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  # Supervisor external input: True, 9
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  # Machine externa input: True, 11
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  # Instruction address misaligned: False, 0
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  # looks like this is giving us an infinite loop for wally
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  # BUG: jumping to a misaligned instruction address doesn't cause an exception: we actually jump...
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  # Either that, or somehow at the end we always end up at 0x80004002
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  # This is fine in OVPsim
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  # writeTest(storecmd, f, r, f"""
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  #   li x1, 11
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  #   jr x1 # Something about this instruction is funky on wally, but fine with ovpsim
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  # """, False, 0)
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  # Instruction access fault: False, 1
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  # Illegal Instruction 
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  writeTest(storecmd, f, r, f"""
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    .fill 1, 4, 0
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  """, False, 2)
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  # Breakpoint
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  if returningInstruction != "ebreak":
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    writeTest(storecmd, f, r, f"""
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      ebreak
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    """, False, 3)
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  # Load Address Misaligned 
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  writeTest(storecmd, f, r, f"""
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    lw x0, 11(x0)
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  """, False, 4)
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  # Load Access fault: False, 5
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  # Store/AMO address misaligned
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  writeTest(storecmd, f, r, f"""
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    sw x0, 11(x0)
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  """, False, 6)
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  # Environment call from u-mode: only for when only M and U mode enabled?
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  # writeTest(storecmd, f, r, f"""
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  #   ecall
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  # """, False, 8, "u")
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  if returningInstruction != "ecall":
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    if fromMode == "u":
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      writeTest(storecmd, f, r, f"""
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        ecall
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      """, False, 8)
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    # Environment call from s-mode
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    if fromMode == "s":
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      writeTest(storecmd, f, r, f"""
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        ecall
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      """, False, 9)
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    # Environment call from m-mode
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    if fromMode == "m":
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      writeTest(storecmd, f, r, f"""
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        ecall
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      """, False, 11)  
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  # Instruction page fault: 12
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  # Load page fault: 13
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  # Store/AMO page fault: 15
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def writeTest(storecmd, f, r, test, interrupt, code, resetHander = ""):
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  global testnum, storeAddressOffset
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  expected = code
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  if(interrupt):
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    expected+=(1 << (xlen - 1))
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  # The code we actually change for our test
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  lines = f"""
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    csrr x25, {testMode}cause
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  """
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  # Boilerplate
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  #
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  # x28 is the address that our trap handler will jump to before returning.
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  # This is where we can do our actual tests. After we're done computing and storing
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  # what we want, we jump to x27, which continues with the trap handling code (look at the _j_x_trap_... labels)
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  # 
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  lines = f"""
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    la x28, _jtest{testnum}
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    j _jdo{testnum}
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    _jtest{testnum}:
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    {lines}
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    {resetHander}
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    jr x27
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    _jdo{testnum}:
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    li x25, 0xDEADBEA7
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    li gp, 0
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    {test}
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  """
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  # We expect x25 to be 0 always. This is because of the code we wrote at the begining
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  # of this function
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  # Store the expected value of x25 to memory and in the .reference_output file
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  lines += f"""
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    {storecmd} x25, {testnum * wordsize}(x6)
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  """
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  f.write(lines)
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  if (xlen == 32):
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    line = formatrefstr.format(expected)+"\n"
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  else:
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    line = formatrefstr.format(expected % 2**32)+"\n" + formatrefstr.format(expected >> 32) + "\n"
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  r.write(line)
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  testnum = testnum+1
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##################################
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# main body
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##################################
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author = "dottolia@hmc.edu"
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xlens = [32, 64]
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testCount = 8;
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# setup
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# Change this seed to a different constant value for every test
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seed(0xC363DAEB9193AB45) # make tests reproducible
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# generate files for each test
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for xlen in xlens:
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  formatstrlen = str(int(xlen/4))
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  formatstr = "0x{:0" + formatstrlen + "x}" # format as xlen-bit hexadecimal number
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  formatrefstr = "{:08x}" # format as xlen-bit hexadecimal number with no leading 0x
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  if (xlen == 32):
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    storecmd = "sw"
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    loadcmd = "lw"
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    wordsize = 4
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  else:
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    storecmd = "sd"
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    loadcmd = "ld"
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    wordsize = 8
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  # testMode can be m, s, and u. User mode traps are deprecated, so this should likely just be ["m", "s"]
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  for testMode in ["m", "s"]:
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    imperaspath = "../../../imperas-riscv-tests/riscv-test-suite/rv" + str(xlen) + "p/"
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    basename = "WALLY-" + testMode.upper() + "CAUSE"
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    fname = imperaspath + "src/" + basename + ".S"
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    refname = imperaspath + "references/" + basename + ".reference_output"
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    testnum = 0
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    storeAddressOffset = 0
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    # print custom header part
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    f = open(fname, "w")
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    r = open(refname, "w")
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    line = "///////////////////////////////////////////\n"
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    f.write(line)
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    lines="// "+fname+ "\n// " + author + "\n"
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    f.write(lines)
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    line ="// Created " + str(datetime.now()) 
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    f.write(line)
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    # insert generic header
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    h = open("../testgen_header.S", "r")
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    for line in h:  
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     f.write(line.replace("RV_COMPLIANCE_RV64M", "RV_COMPLIANCE_RV" + str(xlen) + "M"))
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    # f.write(f"""
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    #   #include "riscv_test_macros.h"
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    #   #include "compliance_test.h"
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    #   #include "compliance_io.h"
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    #   0000000080000000 <_start>:
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    #   80000000: 0480006f            j 80000048 <reset_vector>
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    # """)
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    # We need to leave at least one bit in medeleg unset so that we have a way to get
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    # back to machine mode when the tests are complete (otherwise we'll only ever be able
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    # to get up to supervisor mode). 
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    #
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    # So, we define a returning instruction which will be used to cause the exception that
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    # brings us into machine mode. The bit for this returning instruction is NOT set in
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    # medeleg. However, this also means that we can't test that instruction. So, we have
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    # two different returning instructions.
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    #
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    # Current code is written to only support ebreak and ecall.
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    #
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    # For testgen-TVAL, we don't need to test ebreak, so we can use that as the sole
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    # returning instruction. For others, like testgen-CAUSE, we'll need to put
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    # both ebreak and ecall here.
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    for returningInstruction in ["ebreak"]:
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      # All registers used:
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      # x30: set to 1 if we should return to & stay in machine mode after trap, 0 otherwise
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      # ...
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      # x28: address trap handler should jump to for the test
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      # x27: address the test should return to after the test
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      # ...
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      # x25: value to write to memory
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      # ...
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      # x20: intermediate value in trap handler. Don't overwrite this!
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      # x19: mtvec old value
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      # x18: medeleg old value
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      # x17: sedeleg old value (currently unused — user mode traps deprecated)
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      # x16: mideleg old value
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      # ...
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      # x10 - x14 can be freely written
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      # ...
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      # x7: copy of x6. Increment this instead of using an offset on x6.
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      #     this allows us to create more than 2048/wordlen tests.
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      #     This is the address we write results to
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      # x6: Starting address we should write expected results to
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      # ...
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      # x1 - x5 can be freely written  
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      # Set up x7 and store old value of mtvec
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      lines = f"""
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        add x7, x6, x0
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        csrr x19, mtvec
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        slli  a0,a0,0x1f
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        slli  a0,a0,0x1e
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        slli  a0,a0,0x1d
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        slli  a0,a0,0x1c
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        slli  a0,a0,0x1b
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        slli  a0,a0,0x1a
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        slli  a0,a0,0x19
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      """
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      # Not used — user mode traps are deprecated
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      if testMode == "u":
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        lines += f"""
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          csrr x17, sedeleg
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          li x9, {"0b1100000000" if testMode == "u" else "0b0000000000"}
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          csrs sedeleg, x9
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          """
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      # Code that will jump to the test (x28 is set in writeTest above)
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      testJumpCode = f"""
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        auipc x27, 0
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        addi x27, x27, 12
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        jr x28
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      """
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      # Code for handling traps in different modes
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      # Some comments are inside of the below strings (prefixed with a #, as you might expected)
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      lines += f"""
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        # Reset x30 to 0 so we can run the tests. We'll set this to 1 when tests are completed so we stay in machine mode
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        li x30, 0
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        # Set up 
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        la x1, _j_m_trap_{returningInstruction}
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        csrw mtvec, x1
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        la x1, _j_s_trap_{returningInstruction}
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        csrw stvec, x1
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        la x1, _j_u_trap_{returningInstruction}
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        # csrw utvec, x1 # user mode traps are not supported
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        # Start the tests!
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        j _j_t_begin_{returningInstruction}
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        # Machine mode traps
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						|
        _j_m_trap_{returningInstruction}:
 | 
						|
        {testJumpCode if testMode == "m" else "li x25, 0xBAD00003"}
 | 
						|
 | 
						|
        csrrs x20, mepc, x0
 | 
						|
        addi x20, x20, 4
 | 
						|
        csrrw x0, mepc, x20
 | 
						|
        bnez x30, _j_all_end_{returningInstruction}
 | 
						|
        mret
 | 
						|
 | 
						|
        # Supervisor mode traps
 | 
						|
        _j_s_trap_{returningInstruction}:
 | 
						|
        {testJumpCode if testMode == "s" else "li x25, 0xBAD00001"}
 | 
						|
 | 
						|
        csrrs x20, sepc, x0
 | 
						|
        addi x20, x20, 4
 | 
						|
        csrrw x0, sepc, x20
 | 
						|
        bnez x30, _j_goto_machine_mode_{returningInstruction}
 | 
						|
        sret
 | 
						|
 | 
						|
        # Unused: user mode traps are no longer supported
 | 
						|
        _j_u_trap_{returningInstruction}:
 | 
						|
        {testJumpCode if testMode == "u" else "li x25, 0xBAD00000"}
 | 
						|
 | 
						|
        csrrs x20, uepc, x0
 | 
						|
        addi x20, x20, 4
 | 
						|
        csrrw x0, uepc, x20
 | 
						|
        bnez x30, _j_goto_supervisor_mode_{returningInstruction}
 | 
						|
        uret
 | 
						|
 | 
						|
        # Currently unused. Just jumps to _j_goto_machine_mode. If you actually
 | 
						|
        # want to implement this, you'll likely need to reset sedeleg here
 | 
						|
        # and then cause an exception with {returningInstruction} (based on my intuition. Try that first, but I could be missing something / just wrong)
 | 
						|
        _j_goto_supervisor_mode_{returningInstruction}:
 | 
						|
        j _j_goto_machine_mode_{returningInstruction}
 | 
						|
 | 
						|
        _j_goto_machine_mode_{returningInstruction}:
 | 
						|
        li x30, 1 # This will cause us to branch to _j_all_end_{returningInstruction} in the machine trap handler, which we'll get into by invoking...
 | 
						|
        {returningInstruction} # ... this instruction!
 | 
						|
 | 
						|
        # Run the actual tests!
 | 
						|
        _j_t_begin_{returningInstruction}:
 | 
						|
      """
 | 
						|
 | 
						|
      fromModeOptions = ["m", "s", "u"] if testMode == "m" else (["s", "u"] if testMode == "s" else ["u"])
 | 
						|
 | 
						|
      # We don't want to delegate our returning instruction. Otherwise, we'll have no way of getting
 | 
						|
      # back to machine mode at the end! (and we need to be in machine mode to complete the tests)
 | 
						|
      medelegMask = "0b1111111111110111" if returningInstruction == "ebreak" else "0b1111000011111111"
 | 
						|
 | 
						|
      # Set medeleg and mideleg
 | 
						|
      lines += f"""
 | 
						|
        csrr x18, medeleg
 | 
						|
        li x9, {medelegMask if testMode == "s" or testMode == "u" else "0"}
 | 
						|
        csrw medeleg, x9
 | 
						|
 | 
						|
        csrr x16, mideleg
 | 
						|
        li x9, {"0xffffffff" if testMode == "s" or testMode == "u" else "0"}
 | 
						|
        csrw mideleg, x9
 | 
						|
      """
 | 
						|
 | 
						|
      f.write(lines)
 | 
						|
 | 
						|
      for fromMode in fromModeOptions:
 | 
						|
        lines = ""
 | 
						|
        
 | 
						|
        # Code to bring us down to supervisor mode
 | 
						|
        if fromMode == "s" or fromMode == "u":
 | 
						|
          lines += f"""
 | 
						|
            li x1, 0b110000000000
 | 
						|
            csrrc x31, mstatus, x1
 | 
						|
            li x1, 0b0100000000000
 | 
						|
            csrrs x31, mstatus, x1
 | 
						|
 | 
						|
            auipc x1, 0
 | 
						|
            addi x1, x1, 16 # x1 is now right after the mret instruction
 | 
						|
            csrw mepc, x1
 | 
						|
            mret
 | 
						|
 | 
						|
            # We're now in supervisor mode...
 | 
						|
          """
 | 
						|
 | 
						|
        # Code to bring us down to user mode
 | 
						|
        if fromMode == "u":
 | 
						|
          lines += f"""
 | 
						|
 | 
						|
          li x1, 0b110000000000
 | 
						|
          csrrc x31, sstatus, x1
 | 
						|
 | 
						|
          auipc x1, 0
 | 
						|
          addi x1, x1, 16 # x1 is now right after the sret instruction
 | 
						|
          csrw sepc, x1
 | 
						|
          sret
 | 
						|
 | 
						|
          # We're now in user mode...
 | 
						|
          """
 | 
						|
 | 
						|
        f.write(lines)
 | 
						|
        for i in range(0,testCount):
 | 
						|
          writeVectors(storecmd, returningInstruction)
 | 
						|
 | 
						|
 | 
						|
      # Very end of test. Bring us back up to machine mode
 | 
						|
      # We set x30 to 1, which will cause us to branch to _j_all_end in the
 | 
						|
      # machine mode trap handler, before executing the mret instruction. This will
 | 
						|
      # make us stay in machine mode.
 | 
						|
      #
 | 
						|
      # If we're currently in user mode, this will first bump us up to the supervisor mode
 | 
						|
      # trap handler, which will call returningInstruction again before it's sret instruction,
 | 
						|
      # bumping us up to machine mode
 | 
						|
      #
 | 
						|
      # Get into the trap handler by running returningInstruction (either an ecall or ebreak) 
 | 
						|
      f.write(f"""
 | 
						|
        li x30, 1
 | 
						|
        li gp, 0
 | 
						|
        {returningInstruction}
 | 
						|
        _j_all_end_{returningInstruction}:
 | 
						|
 | 
						|
        # Reset trap handling csrs to old values
 | 
						|
        csrw mtvec, x19
 | 
						|
        csrw medeleg, x18
 | 
						|
        csrw mideleg, x16
 | 
						|
      """)
 | 
						|
 | 
						|
    # print footer
 | 
						|
    h = open("../testgen_footer.S", "r")
 | 
						|
    for line in h:  
 | 
						|
      f.write(line)
 | 
						|
 | 
						|
    # Finish
 | 
						|
    lines = ".fill " + str(testnum) + ", " + str(wordsize) + ", -1\n"
 | 
						|
    lines = lines + "\nRV_COMPLIANCE_DATA_END\n" 
 | 
						|
    f.write(lines)
 | 
						|
    f.close()
 | 
						|
    r.close()
 |