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/*
* typedefs for the run-time system.
*/
typedef int ALIGN; /* pick most stringent type for alignment */
typedef unsigned int DIGIT;
/*
* Default sizing and such.
*/
/*
* Set up typedefs and related definitions depending on whether or not
* ints and pointers are the same size.
*/
#if IntBits != WordBits
typedef long int word;
typedef unsigned long int uword;
#else /* IntBits != WordBits */
typedef int word;
typedef unsigned int uword;
#endif /* IntBits != WordBits */
typedef void *pointer;
/*
* Typedefs to make some things easier.
*/
typedef int (*fptr)();
typedef struct descrip *dptr;
typedef word C_integer;
/*
* A success continuation is referenced by a pointer to an integer function
* that takes no arguments.
*/
typedef int (*continuation) (void);
/*
* Icode consists of operators and arguments. Operators are small integers,
* while arguments may be pointers. To conserve space in icode files on
* computers with 16-bit ints, icode is written by the linker as a mixture
* of ints and words (longs). When an icode file is read in and processed
* by the interpreter, it looks like a C array of mixed ints and words.
* Accessing this "nonstandard" structure is handled by a union of int and
* word pointers and incrementing is done by incrementing the appropriate
* member of the union (see the interpreter). This is a rather dubious
* method and certainly not portable. A better way might be to address
* icode with a char *, but the incrementing code might be inefficient
* (at a place that experiences a lot of execution activity).
*
* For the moment, the dubious coding is isolated under control of the
* size of integers.
*/
#if IntBits != WordBits
typedef union {
int *op;
word *opnd;
} inst;
#else /* IntBits != WordBits */
typedef union {
word *op;
word *opnd;
} inst;
#endif /* IntBits != WordBits */
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