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add backtracking of attributed variable data

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This commit is contained in:
Mark Thom
2019-12-06 20:52:40 -04:00
parent f998d6a99f
commit 3d2c4f0801
3 changed files with 32 additions and 24 deletions
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12
src/prolog/machine/attributed_variables.rs
View File

@@ -36,19 +36,25 @@ impl AttrVarInitializer {
self.attr_var_queue.clear();
self.bindings.clear();
}
#[inline]
pub(super) fn backtrack(&mut self, queue_b: usize, bindings_b: usize) {
self.attr_var_queue.truncate(queue_b);
self.bindings.truncate(bindings_b);
}
}
impl MachineState {
pub(super) fn push_attr_var_binding(&mut self, h: usize, addr: Addr) {
if self.attr_var_init.bindings.is_empty() {
self.attr_var_init.instigating_p = self.p.local();
if self.last_call {
self.attr_var_init.cp = self.cp;
} else {
self.attr_var_init.cp = self.p.local() + 1;
}
self.p = CodePtr::VerifyAttrInterrupt(self.attr_var_init.verify_attrs_loc);
}
@@ -61,6 +67,7 @@ impl MachineState {
.bindings
.iter()
.map(|(ref h, _)| Addr::AttrVar(*h));
let var_list_addr = Addr::HeapCell(self.heap.to_list(iter));
let iter = self
@@ -68,6 +75,7 @@ impl MachineState {
.bindings
.iter()
.map(|(_, ref addr)| addr.clone());
let value_list_addr = Addr::HeapCell(self.heap.to_list(iter));
(var_list_addr, value_list_addr)

36
src/prolog/machine/machine_state.rs
View File

@@ -441,11 +441,10 @@ pub(crate) trait CallPolicy: Any {
machine_st.heap.truncate(machine_st.stack.index_or_frame(b).prelude.h);
let attr_var_init_b = machine_st.stack.index_or_frame(b).prelude.attr_var_init_b;
machine_st
.attr_var_init
.attr_var_queue
.truncate(attr_var_init_b);
let attr_var_init_queue_b = machine_st.stack.index_or_frame(b).prelude.attr_var_init_queue_b;
let attr_var_init_bindings_b = machine_st.stack.index_or_frame(b).prelude.attr_var_init_bindings_b;
machine_st.attr_var_init.backtrack(attr_var_init_queue_b, attr_var_init_bindings_b);
machine_st.hb = machine_st.heap.h;
machine_st.p += 1;
@@ -485,11 +484,10 @@ pub(crate) trait CallPolicy: Any {
machine_st.heap.truncate(machine_st.stack.index_or_frame(b).prelude.h);
let attr_var_init_b = machine_st.stack.index_or_frame(b).prelude.attr_var_init_b;
machine_st
.attr_var_init
.attr_var_queue
.truncate(attr_var_init_b);
let attr_var_init_queue_b = machine_st.stack.index_or_frame(b).prelude.attr_var_init_queue_b;
let attr_var_init_bindings_b = machine_st.stack.index_or_frame(b).prelude.attr_var_init_bindings_b;
machine_st.attr_var_init.backtrack(attr_var_init_queue_b, attr_var_init_bindings_b);
machine_st.hb = machine_st.heap.h;
machine_st.p += offset;
@@ -527,11 +525,10 @@ pub(crate) trait CallPolicy: Any {
machine_st.heap.truncate(machine_st.stack.index_or_frame(b).prelude.h);
let attr_var_init_b = machine_st.stack.index_or_frame(b).prelude.attr_var_init_b;
machine_st
.attr_var_init
.attr_var_queue
.truncate(attr_var_init_b);
let attr_var_init_queue_b = machine_st.stack.index_or_frame(b).prelude.attr_var_init_queue_b;
let attr_var_init_bindings_b = machine_st.stack.index_or_frame(b).prelude.attr_var_init_bindings_b;
machine_st.attr_var_init.backtrack(attr_var_init_queue_b, attr_var_init_bindings_b);
machine_st.b = machine_st.stack.index_or_frame(b).prelude.b;
machine_st.truncate_stack();
@@ -572,11 +569,10 @@ pub(crate) trait CallPolicy: Any {
machine_st.heap.truncate(machine_st.stack.index_or_frame(b).prelude.h);
let attr_var_init_b = machine_st.stack.index_or_frame(b).prelude.attr_var_init_b;
machine_st
.attr_var_init
.attr_var_queue
.truncate(attr_var_init_b);
let attr_var_init_queue_b = machine_st.stack.index_or_frame(b).prelude.attr_var_init_queue_b;
let attr_var_init_bindings_b = machine_st.stack.index_or_frame(b).prelude.attr_var_init_bindings_b;
machine_st.attr_var_init.backtrack(attr_var_init_queue_b, attr_var_init_bindings_b);
machine_st.b = machine_st.stack.index_or_frame(b).prelude.b;
machine_st.truncate_stack();

8
src/prolog/machine/machine_state_impl.rs
View File

@@ -3241,8 +3241,10 @@ impl MachineState {
or_frame.prelude.pstr_tr = self.pstr_tr;
or_frame.prelude.h = self.heap.h;
or_frame.prelude.b0 = self.b0;
or_frame.prelude.attr_var_init_b =
or_frame.prelude.attr_var_init_queue_b =
self.attr_var_init.attr_var_queue.len();
or_frame.prelude.attr_var_init_bindings_b =
self.attr_var_init.bindings.len();
self.b = b;
@@ -3278,7 +3280,9 @@ impl MachineState {
or_frame.prelude.pstr_tr = self.pstr_tr;
or_frame.prelude.h = self.heap.h;
or_frame.prelude.b0 = self.b0;
or_frame.prelude.attr_var_init_b =
or_frame.prelude.attr_var_init_queue_b =
self.attr_var_init.attr_var_queue.len();
or_frame.prelude.attr_var_init_bindings_b =
self.attr_var_init.attr_var_queue.len();
self.b = b;