5.16 Low-Level Implementation of Automatic (Local) Variables

Your program accesses local variables in a procedure using negative offsets from the activation record base address (EBP). Consider the following HLA procedure (which admittedly doesn't do much other than demonstrate the use of local variables):

procedure LocalVars; @nodisplay;
var
     a:int32;
     b:int32;
begin LocalVars;

     mov( 0, a );
     mov( a, eax );
     mov( eax, b );

end LocalVars;

The activation record for LocalVars appears in Figure 5-6.

Activation record for the LocalVars procedure

Figure 5-6. Activation record for the LocalVars procedure

The HLA compiler emits code that is roughly equivalent to the following for the body of this procedure: ...

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