Read and parse input file

[nkanderson]

Working code to read and parse an input trace file (the name of which is specified by the user) with correct default if none specified

From the final project doc: Your testbench must read events from a text file of the following format. You should not make any assumptions about alignment of memory addresses. You can assume that memory references do not cross cache line boundaries. n address where n is 0 read request from L1 data cache 1 write request from L1 data cache 2 read request from L1 instruction cache 3 snooped read request 4 snooped write request 5 snooped read with intent to modify request 6 snooped invalidate command 8 clear the cache and reset all state 9 print contents and state of each valid cache line (doesn’t end simulation!)

The address will be a hex value (without leading 0x). For example: 2 408ed4 0 10019d94 2 408ed8 1 10019d88 2 408edc

So my interpretation is that we'll want a dictionary mapping the event code (0-9) to the description, from the list above. The file itself will have an event code and a hex address (no leading zeros). For the demo, maybe we should simply output the full hex address (32 bits in hex) and the event description.

We need to allow for a user-specified input file, and provide a default if the user does not provide a file.

[reecewayt]

Trace file follows a specific format, for example: [operation_code] [memory_address] 2 408ed4 # This means: "Instruction fetch (code 2) from memory address 408ed4" 0 10019d94 # This means: "Data read (code 0) from memory address 10019d94"

[reecewayt]

Done