This is a simple C compiler which builds DCPU-16 bytecode from a subset of ANSI C.
It currently supports the following features of C:
+ Recursion
+ Pointers
+ Flow control (if/while/for)
+ Heap allocated strings
+ Local variables
+ Global variables
Notably, the following features are lacking:
+ Error handling: invalud code causes compiler crashes with no errors.
+ Any type checking what-so-ever.
+ Structs.
+ Function pointers.
+ Stack arrays.
+ Built-in library
+ Preprocessor
+ Inline assembly
Parsing is done through the pycparser (http://code.google.com/p/pycparser/).
python compiler.py [-n] [-d] [-o outputfile] inputfile
where
-n disables optimizations
-d print debugging information about the compilation
-o outfile writes the output to the given file
The output is the instructions, as base-16 encoded words separated by spaces.
When running any file, the return from main is placed in register I.
int main() {
int a = 2;
int b = 3;
return a+b;
}After running the output through a disassembler, here is what we get:
0x0000:
JSR 0x04 ; Jump to the main method
0x0004:
SET PC, 0x02 ; Loop here forever
SUB SP, 0x03 ; Make space for our variables
SET J, SP ; Copy the stack pointer over to J
SET [J], 0x02 ; Push 2 on to the stack
SET [0x01 + J], 0x03 ; Push 3 on to the stack
SET [0x02 + J], [J] ; Move 2 to the result location
ADD [0x02 + J], [0x01 + J] ; Do the addition with 3
ADD SP, 0x03 ; Start tearing down the satck
SET I, [0x02 + J] ; Copy the return value
SET PC, POP ; Return to the top
ADD SP, 0x03 ; Inserted in case we got here
SET PC, POP ; Inserted in case we got here
More examples are over in the Examples folder if you want to check 'em out