rishi/scryer-prolog
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re: issue #199

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This commit is contained in:
Mark Thom
2019-10-15 02:37:01 -06:00
parent c4269b87c2
commit 9f7d89a3e8
3 changed files with 80 additions and 43 deletions
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46
src/prolog/codegen.rs
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@@ -51,20 +51,32 @@ impl<'a> ConjunctInfo<'a> {
self.has_deep_cut as usize
}
fn mark_unsafe_vars(&self, mut unsafe_var_marker: UnsafeVarMarker, code: &mut Code) {
fn mark_unsafe_vars<Alloc: Allocator<'a>>(
&self,
mut unsafe_var_marker: UnsafeVarMarker,
marker: &Alloc,
code: &mut Code
) {
// target the last goal of the rule for handling unsafe variables.
// we use this weird logic to find the last goal.
let right_index = if let &Line::Control(_) = code.last().unwrap() {
code.len() - 2
let right_index = if let Some(Line::Control(_)) = code.last() {
if code.len() >= 2 {
code.len() - 2
} else {
return;
}
} else {
code.len() - 1
if code.len() >= 1 {
code.len() - 1
} else {
return;
}
};
let mut index = right_index;
if let Line::Query(_) = &code[right_index] {
while let Line::Query(_) = &code[index] {
// index >= 0.
if index == 0 {
break;
} else {
@@ -77,10 +89,10 @@ impl<'a> ConjunctInfo<'a> {
index += 1;
}
unsafe_var_marker.record_unsafe_vars(&self.perm_vs);
unsafe_var_marker.record_unsafe_vars(&self.perm_vs, marker);
for line in code.iter_mut() {
if let &mut Line::Query(ref mut query_instr) = line {
for line in code.iter() {
if let Line::Query(ref query_instr) = line {
unsafe_var_marker.mark_safe_vars(query_instr);
}
}
@@ -269,11 +281,12 @@ impl<'a, TermMarker: Allocator<'a>> CodeGenerator<TermMarker> {
fn collect_var_data(&mut self, mut iter: ChunkedIterator<'a>) -> ConjunctInfo<'a> {
let mut vs = VariableFixtures::new();
while let Some((chunk_num, lt_arity, chunked_terms)) = iter.next() {
for (i, chunked_term) in chunked_terms.iter().enumerate() {
let term_loc = match chunked_term {
&ChunkedTerm::HeadClause(..) => GenContext::Head,
&ChunkedTerm::HeadClause(..) =>
GenContext::Head,
&ChunkedTerm::BodyTerm(_) => {
if i < chunked_terms.len() - 1 {
GenContext::Mid(chunk_num)
@@ -294,8 +307,7 @@ impl<'a, TermMarker: Allocator<'a>> CodeGenerator<TermMarker> {
vs.populate_restricting_sets();
vs.set_perm_vals(has_deep_cut);
let vs = self.marker.drain_var_data(vs);
let vs = self.marker.drain_var_data(vs, num_of_chunks);
ConjunctInfo::new(vs, num_of_chunks, has_deep_cut)
}
@@ -703,9 +715,7 @@ impl<'a, TermMarker: Allocator<'a>> CodeGenerator<TermMarker> {
let iter = ChunkedIterator::from_rule_body(p1, clauses);
self.compile_seq(iter, &conjunct_info, &mut code, false)?;
if conjunct_info.allocates() {
conjunct_info.mark_unsafe_vars(unsafe_var_marker, &mut code);
}
conjunct_info.mark_unsafe_vars(unsafe_var_marker, &self.marker, &mut code);
Self::compile_cleanup(&mut code, &conjunct_info, clauses.last().unwrap_or(p1));
Ok(code)
@@ -747,7 +757,7 @@ impl<'a, TermMarker: Allocator<'a>> CodeGenerator<TermMarker> {
vs.mark_vars_in_chunk(post_order_iter(term), term.arity(), GenContext::Head);
vs.populate_restricting_sets();
self.marker.drain_var_data(vs);
self.marker.drain_var_data(vs, 1);
let mut code = Vec::new();
@@ -802,9 +812,7 @@ impl<'a, TermMarker: Allocator<'a>> CodeGenerator<TermMarker> {
let iter = ChunkedIterator::from_term_sequence(query);
self.compile_seq(iter, &conjunct_info, &mut code, true)?;
if conjunct_info.allocates() {
conjunct_info.mark_unsafe_vars(UnsafeVarMarker::new(), &mut code);
}
conjunct_info.mark_unsafe_vars(UnsafeVarMarker::new(), &self.marker, &mut code);
if let Some(query_term) = query.last() {
Self::compile_cleanup(&mut code, &conjunct_info, query_term);