Using main.native for testing:

* To run the automated test harness do:
  - on OS X:   ./main.native --test              
  - on Linux:  ./main.native -linux --test     

* To compile ll files using the 341 backend:
  ./main.native path/to/foo.ll 

  - creates output/foo.s   backend assembly code
  - creates output/foo.o   assembled object file
  - creates a.out          linked executable

 NOTE: by default the .s and .o files are created in 
 a directory called output, and the filenames are 
 chosen so that multiple runs of the compiler will
 not overwrite previous outputs.  foo.ll will be 
 compiled first to foo.s then foo_1.s, foo_2.s, etc.


* To compile ll files using the clang backend:
  ./main.native --clang path/to/foo.ll

* Flags:
  --print-oat
    pretty prints the Oat abstract syntax to the terminal

  --print-ll 
    echoes the ll program to the terminal

  --print-x86
    echoes the resulting .s file to the terminal

  --interpret-ll
    runs the ll file through the reference interpreter
    and outputs the results to the console

  --simulate-x86
    runs the resulting .s file through the reference 
    x86 simulator and outputs the result to the console

  --execute-x86
    runs the resulting a.out file natively
    (applies to either the 341 backend or clang-compiled code)

  -v
    generates verbose output, showing which commands are used
    for linking, etc.

  -op <dirname>
    change the output path [DEFAULT=output]

  -o 
    change the generated executable's name [DEFAULT=a.out]

  -S
    stop after generating .s files 

  -c 
    stop after generating .o files 

  -h or --help
    display the list of options

* Example uses:

Run the test case /programs/factrect.ll using the 341 backend:


./main.native --execute-x86 oatprograms/example.oat --clang
--------------------------------------------------------------- Executing: a.out
CIS341 ROCKS; CIS120 ROCKS too!
* a.out returned 0


Run the test