inline store & deref calls in ''
@@ -211,50 +211,56 @@ fn add_pstr_chars_and_step(&mut self, heap: &[HeapCellValue], h: usize) -> Optio
impl MachineState {
#[inline(always)]
pub fn brents_alg_step(&self, brent_st: &mut BrentAlgState) -> Option<CycleSearchResult> {
- let deref_v = self.deref(self.heap[brent_st.hare]);
- let store_v = self.store(deref_v);
-
- if let Some(var) = store_v.as_var() {
- return Some(CycleSearchResult::PartialList(brent_st.num_steps(), var));
- }
-
- if store_v == empty_list_as_cell!() {
- return Some(CycleSearchResult::ProperList(brent_st.num_steps()));
- }
+ loop {
+ let store_v = self.heap[brent_st.hare];
read_heap_cell!(store_v,
(HeapCellValueTag::PStrLoc, h) => {
- brent_st.add_pstr_chars_and_step(&self.heap, h)
+ return brent_st.add_pstr_chars_and_step(&self.heap, h);
}
(HeapCellValueTag::PStrOffset) => {
- brent_st.add_pstr_chars_and_step(&self.heap, brent_st.hare)
+ return brent_st.add_pstr_chars_and_step(&self.heap, brent_st.hare);
}
(HeapCellValueTag::CStr, cstr_atom) => {
let cstr = PartialString::from(cstr_atom);
brent_st.pstr_chars += cstr.as_str_from(0).chars().count();
- Some(CycleSearchResult::ProperList(brent_st.num_steps()))
+ return Some(CycleSearchResult::ProperList(brent_st.num_steps()));
}
(HeapCellValueTag::Lis, h) => {
- brent_st.step(h+1)
+ return brent_st.step(h+1);
}
(HeapCellValueTag::Str, s) => {
let (name, arity) = cell_as_atom_cell!(self.heap[s]).get_name_and_arity();
- if name == atom!(".") && arity == 2 {
+ return if name == atom!(".") && arity == 2 {
brent_st.step(s+2)
} else {
Some(CycleSearchResult::NotList)
+ };
}
- }
- (HeapCellValueTag::Atom, (_name, arity)) => {
+ (HeapCellValueTag::Atom, (name, arity)) => {
debug_assert!(arity == 0);
+
+ return if name == atom!("[]") {
+ Some(CycleSearchResult::ProperList(brent_st.num_steps()))
+ } else {
Some(CycleSearchResult::NotList)
+ };
+ }
+ (HeapCellValueTag::AttrVar | HeapCellValueTag::Var, h) => {
+ if brent_st.hare == h {
+ let r = store_v.as_var().unwrap();
+ return Some(CycleSearchResult::PartialList(brent_st.num_steps(), r));
+ }
+
+ brent_st.hare = h;
}
_ => {
- Some(CycleSearchResult::NotList)
+ return Some(CycleSearchResult::NotList);
+ }
+ );
}
- )
}
pub fn detect_cycles(&self, value: HeapCellValue) -> CycleSearchResult {
