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don't append lists of attributes when binding attributed variables (#353)

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This commit is contained in:
Mark Thom
2020-04-28 01:40:11 -06:00
parent ab77a1cbc0
commit 77cf0fd87b
2 changed files with 22 additions and 28 deletions
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3
src/prolog/lib/atts.pl
View File

@@ -56,7 +56,8 @@
'$del_attr'(Ls0, V, Attr) :- '$del_attr'(Ls0, V, Attr) :-
Ls0 = [Att | Ls1], Ls0 = [Att | Ls1],
nonvar(Att), nonvar(Att),
( Att \= Attr -> '$del_attr_buried'(Ls0, Ls1, V, Attr) ( Att \= Attr ->
'$del_attr_buried'(Ls0, Ls1, V, Attr)
; '$enqueue_attr_var'(V), ; '$enqueue_attr_var'(V),
'$del_attr_head'(V), '$del_attr_head'(V),
'$del_attr'(Ls1, V, Attr) '$del_attr'(Ls1, V, Attr)

47
src/prolog/machine/system_calls.rs
View File

@@ -1815,6 +1815,9 @@ impl MachineState {
Addr::Lis(l) => { Addr::Lis(l) => {
let tail = self.store(self.deref(Addr::HeapCell(l + 1))); let tail = self.store(self.deref(Addr::HeapCell(l + 1)));
let tail = if tail.is_ref() { let tail = if tail.is_ref() {
self.heap[h] = HeapCellValue::Addr(Addr::HeapCell(h));
self.trail(TrailRef::Ref(Ref::AttrVar(h)));
Addr::HeapCell(h + 1) Addr::HeapCell(h + 1)
} else { } else {
tail tail
@@ -1823,10 +1826,14 @@ impl MachineState {
self.heap[h + 1] = HeapCellValue::Addr(tail); self.heap[h + 1] = HeapCellValue::Addr(tail);
self.trail(TrailRef::AttrVarListLink(h + 1, l)); self.trail(TrailRef::AttrVarListLink(h + 1, l));
} }
_ => unreachable!(), _ => {
unreachable!();
}
} }
} }
_ => unreachable!(), _ => {
unreachable!();
}
} }
} }
&SystemClauseType::DynamicModuleResolution(narity) => { &SystemClauseType::DynamicModuleResolution(narity) => {
@@ -2229,16 +2236,16 @@ impl MachineState {
Addr::AttrVar(h) => { Addr::AttrVar(h) => {
h + 1 h + 1
} }
attr_var @ Addr::HeapCell(_) attr_var @ Addr::HeapCell(_) |
| attr_var @ Addr::StackCell(..) => { attr_var @ Addr::StackCell(..) => {
// create an AttrVar in the heap. // create an AttrVar in the heap.
let h = self.heap.h(); let h = self.heap.h();
self.heap.push(HeapCellValue::Addr(Addr::AttrVar(h))); self.heap.push(HeapCellValue::Addr(Addr::AttrVar(h)));
self.heap.push(HeapCellValue::Addr(Addr::HeapCell(h + 1))); self.heap.push(HeapCellValue::Addr(Addr::HeapCell(h + 1)));
self.bind(Ref::AttrVar(h), attr_var); self.bind(Ref::AttrVar(h), attr_var);
h + 1 h + 1
} }
_ => { _ => {
self.fail = true; self.fail = true;
@@ -2247,7 +2254,7 @@ impl MachineState {
}; };
let list_addr = self[temp_v!(2)]; let list_addr = self[temp_v!(2)];
self.unify(Addr::HeapCell(attr_var_list), list_addr); self.bind(Ref::HeapCell(attr_var_list), list_addr);
} }
&SystemClauseType::GetAttrVarQueueDelimiter => { &SystemClauseType::GetAttrVarQueueDelimiter => {
let addr = self[temp_v!(1)]; let addr = self[temp_v!(1)];
@@ -2658,26 +2665,12 @@ impl MachineState {
}; };
} }
&SystemClauseType::RedoAttrVarBinding => { &SystemClauseType::RedoAttrVarBinding => {
let var = self.store(self.deref(self[temp_v!(1)])); let var = self.store(self.deref(self[temp_v!(1)]));
let value = self.store(self.deref(self[temp_v!(2)])); let value = self.store(self.deref(self[temp_v!(2)]));
match var { match var {
Addr::AttrVar(h) => { Addr::AttrVar(h) => {
if let Addr::AttrVar(h1) = value { self.heap[h] = HeapCellValue::Addr(value);
self.heap[h] = HeapCellValue::Addr(Addr::AttrVar(h1));
// append h's attributes list to h1's.
let mut l = h1 + 1;
while let Addr::Lis(l1) = self.store(self.deref(self.heap[l].as_addr(l))) {
l = l1 + 1;
}
self.heap[l] = HeapCellValue::Addr(Addr::HeapCell(h + 1));
self.trail(TrailRef::Ref(Ref::HeapCell(l)));
} else {
self.heap[h] = HeapCellValue::Addr(value);
}
} }
_ => { _ => {
unreachable!() unreachable!()