SPIM Command-Line Options - Lecture Notes | CS 413, Study notes of Computer Science

Download SPIM Command-Line Options - Lecture Notes | CS 413 and more Study notes Computer Science in PDF only on Docsity! SPIM Command-Line Options 1 SPIM Command-Line Options All versions of SPIM (spim, xspim, and PCSpim) have command-line options that control how SPIM starts running. The general format is spim arguments file.s program_arguments where spim is the name of a particular version of SPIM (spim , PCSpim , or xspim ), arguments are the command-line options described below, file.s is the name of a file containing a MIPS program, and program_arguments are the initial arguments passed to the MIPS program. For example, to just start xspim without any arguments or an initial program, type xspim Or, to start PCSpim with delayed branches on file test.s , type pcspim -delayed_branches test.s The programs accept the following command-line options: -asm , -a Simulate the virtual MIPS machine provided by the assembler. This is the default. -bare , -b Simulate a bare MIPS machine without pseudoin- structions or the additional addressing modes pro- vided by the assembler. Implies the flags -quiet , - delayed_branches , and -delayed_loads . -delayed_branches , Execute the instruction following a branch or -db jump in its delay slot. The offset in a branch must be adjusted to reflect that the control transfer occurs when the PC points to the instruction in the delay slot. The default does not simulate the delay slot, so the offset is relative to the branch instruction. -delayed_loads , dl A value loaded from memory is not available to the instruction executed immediately after the load instruction. The default is that loaded values are available immediately. -exception , -e Load the standard exception handler and start-up code. This is the default. -noexception , -ne Do not load the standard exception handler or start-up code. The program must provide code to 2 SPIM Command-Line Options handle exceptions. When an exception occurs, SPIM jumps to location 80000180 hex . The start-up code invokes the routine main with arguments argc and argv . Without the start-up routine, SPIM starts execution at the instruction labeled __start . -exception_file , ef Load the the exception handler and start-up code from this file instead of the default file. -mapped_io , mio Enable the memory-mapped I/O facility (see Section A.8). Programs that use SPIM syscalls (see section on "System Calls," page A-43) to read from the terminal cannot also use memory- mapped I/O. -nomapped_io , nmio Disable the memory-mapped I/O facility (see Section A.8). This is the default. -pseudo , -p Allow the input assembly code to contain pseudo- instructions. This is the default. -nopseudo , -np Do not allow pseudoinstructions in the input assembly code. -quiet , -q Do not print a message when exceptions occur. -noquiet , -nq Print a message when an exception occurs. This is the default. -file <name> , -f Load and execute the assembly code in the file whose name is given. -s <seg> size,-st, Sets the initial size of memory segment seg to be -sd,-ss,-skt,-skd size bytes. The memory segments are named text , data , stack , ktext , and kdata . The text seg- ment contains instructions from a program. The data segment holds the program’s data. The stack segment holds its runtime stack. In addition to running a program, SPIM also executes system code that handles interrupts and exceptions. This code resides in a separate part of the address space called the kernel . The ktext segment holds this code’s instructions, and kdata holds its data. There is no kstack segment since the system code