Stack* init_stack(Stack *uplink)
{
Stack *s = (Stack*)calloc(1, sizeof(Stack));
s->elem = 16;
s->uplink = uplink;
resize_stack(s);
return s;
}
int push_value(Stack *s, int val)
{
if (s->top == s->elem) {
s->elem += 16;
resize_stack(s);
}
int offset = ((int)(&s->values[s->top] - &s->values[0])) * sizeof(int);
s->values[s->top++] = val;
return offset;
}
/**
* Checks the size of the given stack and expands it if it is full.
* returns: true if the stack doesn't need to be resized or it is
* resized successfully, and false if it is unable to be resized.
*/
static bool check_size(TypeStk * stack) {
/* if no space remains in the stack, expand it by blockSize */
if((stack->depth - stack->size) != 0) {
return true;
}
if(resize_stack(stack, stack->size + stack->blockSize)) {
return true;
}
return false;
}
void glstack_ensure_space(CTXTdeclc size_t extra, int arity) {
if ((pb)top_of_localstk < (pb)top_of_heap+(256*ZOOM_FACTOR)) {
xsb_basic_abort("\nFatal ERROR: -- "
"Local Stack clobbered Heap --\n");
} else {
if (pflags[STACK_REALLOC] == FALSE) xsb_basic_abort(local_global_exception);
if (pflags[GARBAGE_COLLECT] != NO_GC && arity < 255) {
gc_heap(CTXTc arity,FALSE);
}
if ((pb)top_of_localstk < (pb)top_of_heap + OVERFLOW_MARGIN + extra) {
glstack_realloc(CTXTc resize_stack(glstack.size,extra+OVERFLOW_MARGIN),arity);
}
}
}
int load_value(Stack *s, int offset)
{
int idx = offset / sizeof(int);
// increase size of stack if necessary
if (idx >= s->elem) {
s->elem = (idx+1 + 15) / 16 * 16;
resize_stack(s);
}
// adjust top of stack if needed
if (idx >= s->top) s->top = idx+1;
// load value
return s->values[idx];
}
void store_value(Stack *s, int offset, int val)
{
int idx = offset / sizeof(int);
// increase size of stack if necessary
if (idx >= s->elem) {
s->elem = (idx+1 + 15) / 16 * 16;
resize_stack(s);
}
// adjust top of stack if needed
if (idx >= s->top) s->top = idx+1;
// store value
s->values[idx] = val;
}