Objects are stored in memory just as ordinary records with an extra eld: a pointer to the Virtual Method Table (VMT). This eld is stored rst, and all elds in the object are stored in the order they are declared (with possible alignment of eld addresses, unless the object was declared as being packed).
This eld is initialized by the call to the object's Constructor method. If the new operator was used to call the constructor, the data elds of the object will be stored in heap memory, otherwise they will directly be stored in the data section of the nal executable.
If an object doesn't have virtual methods, no pointer to a VMT is inserted.
The memory allocated looks as in table (8.4).
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The Virtual Method Table (VMT) for each object type consists of 2 check elds (containing the size of the data), a pointer to the object's ancestor's VMT (Nil if there is no ancestor), and then the pointers to all virtual methods. The VMT layout is illustrated in table (8.5). The VMT is constructed by the compiler.
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