MiniIR SPECIFICATION

MiniIR (Minijava Intermediate Representation) is an intermediate
representation for Minijava. It has simplified expressions, exposes the
runtime model (integer is of size 4, field and method references require
accessing of the address of the object, "new" operator is replaced with
system call HALLOCATE).


procedures:
    If we have a procedure
        p [5] s
    then it takes five arguments, called (temp 0), (temp 1), ..., (temp 4).
    Other temporaries can be used without declaration.

arrays:
    The index of an array is a multiple of 4, starting at 0.

NOOP:
    Does nothing.

ERROR:
    Terminates the program execution with an error message.

CJUMP Exp Label:
    If Exp evaluates to 1, then continue with the next statement,
    otherwise jump to Label.

HSTORE Exp_1 IntegerLiteral Exp_2:
    Exp_1 evaluates to an address
    IntegerLiteral is an offset
    Exp_2 evaluates to the value that should be stored.

HLOAD Temp Exp IntegerLiteral
    Temp is the temporary into which a value should be loaded
    Exp evaluates to an address
    IntegerLiteral is an offset.

LT: is "<"
   
HALLOCATE Exp:
    Exp evaluates to an integer, and that corresponding amount of heapspace
    is allocated, and the return address of that is returned as the result.