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/*
* variable.c
*
* Variable manipulation routines
*
*/
#include "ztypes.h"
/*
* load
*
* Load and store a variable value.
*
*/
void load (zword_t variable)
{
store_operand (load_variable (variable));
}/* load */
/*
* push_var
*
* Push a value onto the stack
*
*/
void push_var (zword_t value)
{
stack[--sp] = value;
}/* push_var */
/*
* pop_var
*
* Pop a variable from the stack.
*
*/
void pop_var (zword_t variable)
{
store_variable (variable, stack[sp++]);
}/* pop_var */
/*
* increment
*
* Increment a variable.
*
*/
void increment (zword_t variable)
{
store_variable (variable, load_variable (variable) + 1);
}/* increment */
/*
* decrement
*
* Decrement a variable.
*
*/
void decrement (zword_t variable)
{
store_variable (variable, load_variable (variable) - 1);
}/* decrement */
/*
* increment_check
*
* Increment a variable and then check its value against a target.
*
*/
void increment_check (zword_t variable, zword_t target)
{
short value;
value = (short) load_variable (variable);
store_variable (variable, ++value);
conditional_jump (value > (short) target);
}/* increment_check */
/*
* decrement_check
*
* Decrement a variable and then check its value against a target.
*
*/
void decrement_check (zword_t variable, zword_t target)
{
short value;
value = (short) load_variable (variable);
store_variable (variable, --value);
conditional_jump (value < (short) target);
}/* decrement_check */
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