619 lines
18 KiB
Rust
619 lines
18 KiB
Rust
use prolog_parser::ast::*;
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use prolog_parser::tabled_rc::*;
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use prolog::clause_types::*;
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use prolog::fixtures::*;
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use prolog::forms::*;
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use indexmap::IndexMap;
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use std::cell::RefCell;
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use std::cmp::Ordering;
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use std::collections::{BTreeMap, VecDeque};
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use std::mem;
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use std::ops::{Add, AddAssign, Sub, SubAssign};
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use std::rc::Rc;
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#[derive(Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
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pub struct OrderedOpDirKey(pub ClauseName, pub Fixity);
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pub type OssifiedOpDir = BTreeMap<OrderedOpDirKey, (usize, Specifier)>;
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#[derive(Clone, PartialEq, Eq, Hash)]
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pub enum DBRef {
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NamedPred(ClauseName, usize, Option<SharedOpDesc>),
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Op(usize, Specifier, ClauseName, Rc<OssifiedOpDir>, SharedOpDesc)
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}
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#[derive(Clone, PartialEq, Eq, Hash)]
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pub enum Addr {
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AttrVar(usize),
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Con(Constant),
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DBRef(DBRef),
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Lis(usize),
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HeapCell(usize),
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StackCell(usize, usize),
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Str(usize)
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}
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#[derive(Clone, Copy, Hash, Eq, PartialEq)]
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pub enum Ref {
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AttrVar(usize),
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HeapCell(usize),
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StackCell(usize, usize)
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}
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impl Ref {
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pub fn as_addr(self) -> Addr {
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match self {
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Ref::AttrVar(h) => Addr::AttrVar(h),
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Ref::HeapCell(h) => Addr::HeapCell(h),
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Ref::StackCell(fr, sc) => Addr::StackCell(fr, sc)
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}
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}
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}
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impl PartialEq<Ref> for Addr {
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fn eq(&self, r: &Ref) -> bool {
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self.as_var() == Some(*r)
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}
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}
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// for use in MachineState::bind.
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impl PartialOrd<Ref> for Addr {
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fn partial_cmp(&self, r: &Ref) -> Option<Ordering> {
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match self {
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&Addr::StackCell(fr, sc) =>
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match *r {
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Ref::AttrVar(_) | Ref::HeapCell(_) =>
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Some(Ordering::Greater),
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Ref::StackCell(fr1, sc1) =>
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if fr1 < fr || (fr1 == fr && sc1 < sc) {
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Some(Ordering::Greater)
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} else if fr1 == fr && sc1 == sc {
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Some(Ordering::Equal)
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} else {
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Some(Ordering::Less)
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}
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},
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&Addr::HeapCell(h) | &Addr::AttrVar(h) =>
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match r {
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&Ref::StackCell(..) => Some(Ordering::Less),
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&Ref::AttrVar(h1) | &Ref::HeapCell(h1) => h.partial_cmp(&h1)
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},
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_ => None
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}
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}
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}
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impl Addr {
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pub fn is_ref(&self) -> bool {
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match self {
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&Addr::AttrVar(_) | &Addr::HeapCell(_) | &Addr::StackCell(_, _) => true,
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_ => false
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}
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}
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pub fn as_var(&self) -> Option<Ref> {
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match self {
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&Addr::AttrVar(h) => Some(Ref::AttrVar(h)),
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&Addr::HeapCell(h) => Some(Ref::HeapCell(h)),
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&Addr::StackCell(fr, sc) => Some(Ref::StackCell(fr, sc)),
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_ => None
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}
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}
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pub fn is_protected(&self, e: usize) -> bool {
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match self {
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&Addr::StackCell(addr, _) if addr >= e => false,
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_ => true
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}
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}
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}
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impl Add<usize> for Addr {
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type Output = Addr;
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fn add(self, rhs: usize) -> Self::Output {
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match self {
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Addr::Lis(a) => Addr::Lis(a + rhs),
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Addr::AttrVar(h) => Addr::AttrVar(h + rhs),
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Addr::HeapCell(h) => Addr::HeapCell(h + rhs),
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Addr::Str(s) => Addr::Str(s + rhs),
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_ => self
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}
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}
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}
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impl Sub<i64> for Addr {
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type Output = Addr;
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fn sub(self, rhs: i64) -> Self::Output {
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if rhs < 0 {
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match self {
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Addr::Lis(a) => Addr::Lis(a + rhs.abs() as usize),
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Addr::AttrVar(h) => Addr::AttrVar(h + rhs.abs() as usize),
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Addr::HeapCell(h) => Addr::HeapCell(h + rhs.abs() as usize),
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Addr::Str(s) => Addr::Str(s + rhs.abs() as usize),
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_ => self
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}
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} else {
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self.sub(rhs as usize)
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}
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}
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}
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impl Sub<usize> for Addr {
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type Output = Addr;
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fn sub(self, rhs: usize) -> Self::Output {
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match self {
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Addr::Lis(a) => Addr::Lis(a - rhs),
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Addr::AttrVar(h) => Addr::AttrVar(h - rhs),
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Addr::HeapCell(h) => Addr::HeapCell(h - rhs),
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Addr::Str(s) => Addr::Str(s - rhs),
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_ => self
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}
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}
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}
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impl SubAssign<usize> for Addr {
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fn sub_assign(&mut self, rhs: usize) {
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*self = self.clone() - rhs;
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}
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}
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impl From<Ref> for Addr {
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fn from(r: Ref) -> Self {
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match r {
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Ref::AttrVar(h) => Addr::AttrVar(h),
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Ref::HeapCell(h) => Addr::HeapCell(h),
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Ref::StackCell(fr, sc) => Addr::StackCell(fr, sc)
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}
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}
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}
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#[derive(Clone)]
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pub enum TrailRef {
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Ref(Ref),
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AttrVarLink(usize, Addr)
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}
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impl From<Ref> for TrailRef {
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fn from(r: Ref) -> Self {
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TrailRef::Ref(r)
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}
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}
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#[derive(Clone, PartialEq)]
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pub enum HeapCellValue {
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Addr(Addr),
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NamedStr(usize, ClauseName, Option<SharedOpDesc>), // arity, name, precedence/Specifier if it has one.
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}
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impl HeapCellValue {
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pub fn as_addr(&self, focus: usize) -> Addr {
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match self {
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&HeapCellValue::Addr(ref a) => a.clone(),
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&HeapCellValue::NamedStr(_, _, _) => Addr::Str(focus)
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}
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}
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}
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#[derive(Clone, Copy, Eq, PartialEq, Ord, PartialOrd)]
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pub enum IndexPtr {
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Undefined,
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Index(usize),
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}
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#[derive(Clone, Ord, PartialOrd, Eq, PartialEq)]
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pub struct CodeIndex(pub Rc<RefCell<(IndexPtr, ClauseName)>>);
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impl CodeIndex {
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#[inline]
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pub fn is_undefined(&self) -> bool {
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let index_ptr = &self.0.borrow().0;
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if let &IndexPtr::Undefined = index_ptr {
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true
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} else {
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false
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}
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}
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#[inline]
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pub fn module_name(&self) -> ClauseName {
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self.0.borrow().1.clone()
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}
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pub fn local(&self) -> Option<usize> {
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match self.0.borrow().0 {
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IndexPtr::Index(i) => Some(i),
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_ => None
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}
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}
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}
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impl Default for CodeIndex {
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fn default() -> Self {
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CodeIndex(Rc::new(RefCell::new((IndexPtr::Undefined, clause_name!("")))))
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}
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}
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impl From<(usize, ClauseName)> for CodeIndex {
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fn from(value: (usize, ClauseName)) -> Self {
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CodeIndex(Rc::new(RefCell::new((IndexPtr::Index(value.0), value.1))))
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}
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}
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#[derive(Clone, Copy, PartialEq)]
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pub enum DynamicAssertPlace {
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Back, Front
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}
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impl DynamicAssertPlace {
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#[inline]
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pub fn predicate_name(self) -> ClauseName {
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match self {
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DynamicAssertPlace::Back => clause_name!("assertz"),
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DynamicAssertPlace::Front => clause_name!("asserta")
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}
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}
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#[inline]
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pub fn push_to_queue(self, addrs: &mut VecDeque<Addr>, new_addr: Addr) {
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match self {
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DynamicAssertPlace::Back => addrs.push_back(new_addr),
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DynamicAssertPlace::Front => addrs.push_front(new_addr)
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}
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}
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}
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#[derive(Clone, Copy, PartialEq)]
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pub enum DynamicTransactionType {
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Abolish,
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Assert(DynamicAssertPlace),
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ModuleAbolish,
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ModuleAssert(DynamicAssertPlace),
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ModuleRetract,
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Retract // dynamic index of the clause to remove.
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}
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#[derive(Clone, Copy, PartialOrd, Ord, PartialEq, Eq)]
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pub enum REPLCodePtr {
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CompileBatch,
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SubmitQueryAndPrintResults
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}
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#[derive(Clone, PartialEq)]
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pub enum CodePtr {
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BuiltInClause(BuiltInClauseType, LocalCodePtr), // local is the successor call.
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CallN(usize, LocalCodePtr), // arity, local.
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Local(LocalCodePtr),
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DynamicTransaction(DynamicTransactionType, LocalCodePtr), // the type of transaction, the return pointer.
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REPL(REPLCodePtr, LocalCodePtr), // the REPL code, the return pointer.
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VerifyAttrInterrupt(usize) // location of the verify attribute interrupt code in the CodeDir.
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}
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impl CodePtr {
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pub fn local(&self) -> LocalCodePtr {
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match self {
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&CodePtr::BuiltInClause(_, ref local)
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| &CodePtr::CallN(_, ref local)
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| &CodePtr::Local(ref local) => local.clone(),
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&CodePtr::VerifyAttrInterrupt(p) => LocalCodePtr::DirEntry(p),
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&CodePtr::REPL(_, p)
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| &CodePtr::DynamicTransaction(_, p) => p
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}
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}
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}
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#[derive(Copy, Clone, PartialEq)]
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pub enum LocalCodePtr {
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DirEntry(usize), // offset.
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InSituDirEntry(usize),
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TopLevel(usize, usize), // chunk_num, offset.
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UserGoalExpansion(usize),
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UserTermExpansion(usize)
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}
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impl LocalCodePtr {
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pub fn assign_if_local(&mut self, cp: CodePtr) {
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match cp {
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CodePtr::Local(local) => *self = local,
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_ => {}
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}
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}
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}
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impl PartialOrd<CodePtr> for CodePtr {
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fn partial_cmp(&self, other: &CodePtr) -> Option<Ordering> {
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match (self, other) {
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(&CodePtr::Local(ref l1), &CodePtr::Local(ref l2)) => l1.partial_cmp(l2),
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_ => Some(Ordering::Greater)
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}
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}
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}
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impl PartialOrd<LocalCodePtr> for LocalCodePtr {
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fn partial_cmp(&self, other: &LocalCodePtr) -> Option<Ordering> {
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match (self, other) {
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(&LocalCodePtr::InSituDirEntry(p1), &LocalCodePtr::InSituDirEntry(ref p2))
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| (&LocalCodePtr::DirEntry(p1), &LocalCodePtr::DirEntry(ref p2))
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| (&LocalCodePtr::UserTermExpansion(p1), &LocalCodePtr::UserTermExpansion(ref p2))
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| (&LocalCodePtr::UserGoalExpansion(p1), &LocalCodePtr::UserGoalExpansion(ref p2))
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| (&LocalCodePtr::TopLevel(_, p1), &LocalCodePtr::TopLevel(_, ref p2)) =>
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p1.partial_cmp(p2),
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(_, &LocalCodePtr::TopLevel(_, _)) =>
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Some(Ordering::Less),
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_ => Some(Ordering::Greater)
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}
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}
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}
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impl Default for CodePtr {
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fn default() -> Self {
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CodePtr::Local(LocalCodePtr::default())
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}
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}
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impl Default for LocalCodePtr {
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fn default() -> Self {
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LocalCodePtr::TopLevel(0, 0)
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}
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}
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impl Add<usize> for LocalCodePtr {
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type Output = LocalCodePtr;
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fn add(self, rhs: usize) -> Self::Output {
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match self {
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LocalCodePtr::InSituDirEntry(p) => LocalCodePtr::InSituDirEntry(p + rhs),
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LocalCodePtr::DirEntry(p) => LocalCodePtr::DirEntry(p + rhs),
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LocalCodePtr::TopLevel(cn, p) => LocalCodePtr::TopLevel(cn, p + rhs),
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LocalCodePtr::UserTermExpansion(p) => LocalCodePtr::UserTermExpansion(p + rhs),
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LocalCodePtr::UserGoalExpansion(p) => LocalCodePtr::UserGoalExpansion(p + rhs),
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}
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}
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}
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impl AddAssign<usize> for LocalCodePtr {
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fn add_assign(&mut self, rhs: usize) {
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match self {
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&mut LocalCodePtr::InSituDirEntry(ref mut p)
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| &mut LocalCodePtr::UserGoalExpansion(ref mut p)
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| &mut LocalCodePtr::UserTermExpansion(ref mut p)
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| &mut LocalCodePtr::DirEntry(ref mut p)
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| &mut LocalCodePtr::TopLevel(_, ref mut p) => *p += rhs
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}
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}
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}
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impl Add<usize> for CodePtr {
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type Output = CodePtr;
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fn add(self, rhs: usize) -> Self::Output {
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match self {
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p @ CodePtr::REPL(..)
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| p @ CodePtr::VerifyAttrInterrupt(_)
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| p @ CodePtr::DynamicTransaction(..) => p,
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CodePtr::Local(local) => CodePtr::Local(local + rhs),
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CodePtr::CallN(_, local) | CodePtr::BuiltInClause(_, local) => CodePtr::Local(local + rhs)
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}
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}
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}
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impl AddAssign<usize> for CodePtr {
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fn add_assign(&mut self, rhs: usize) {
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match self {
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&mut CodePtr::VerifyAttrInterrupt(_) => {},
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&mut CodePtr::Local(ref mut local) => *local += rhs,
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_ => *self = CodePtr::Local(self.local() + rhs)
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}
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}
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}
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pub type HeapVarDict = IndexMap<Rc<Var>, Addr>;
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pub type AllocVarDict = IndexMap<Rc<Var>, VarData>;
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#[derive(Clone)]
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pub struct DynamicPredicateInfo {
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pub(super) clauses_subsection_p: usize, // a LocalCodePtr::DirEntry value.
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}
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impl Default for DynamicPredicateInfo {
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fn default() -> Self {
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DynamicPredicateInfo { clauses_subsection_p: 0 }
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}
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}
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pub type InSituCodeDir = IndexMap<PredicateKey, usize>;
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// key type: module name, predicate indicator.
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pub type DynamicCodeDir = IndexMap<(ClauseName, ClauseName, usize), DynamicPredicateInfo>;
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pub type GlobalVarDir = IndexMap<ClauseName, Addr>;
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pub struct IndexStore {
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pub(super) atom_tbl: TabledData<Atom>,
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pub(super) code_dir: CodeDir,
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pub(super) dynamic_code_dir: DynamicCodeDir,
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pub(super) global_variables: GlobalVarDir,
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pub(super) in_situ_code_dir: InSituCodeDir,
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pub(super) modules: ModuleDir,
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pub(super) op_dir: OpDir,
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}
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impl IndexStore {
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pub fn predicate_exists(&self, name: ClauseName, module: ClauseName, arity: usize,
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op_spec: Option<SharedOpDesc>)
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-> bool
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{
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match self.modules.get(&module) {
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Some(module) =>
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match ClauseType::from(name, arity, op_spec) {
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ClauseType::Named(name, arity, _) =>
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module.code_dir.contains_key(&(name, arity)),
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ClauseType::Op(name, spec, ..) =>
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module.code_dir.contains_key(&(name, spec.arity())),
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_ =>
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true
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},
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None =>
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match ClauseType::from(name, arity, op_spec) {
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ClauseType::Named(name, arity, _) =>
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self.code_dir.contains_key(&(name, arity)),
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ClauseType::Op(name, spec, ..) =>
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self.code_dir.contains_key(&(name, spec.arity())),
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_ =>
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true
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}
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}
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}
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|
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#[inline]
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pub fn remove_clause_subsection(&mut self, module: ClauseName, name: ClauseName, arity: usize)
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{
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self.dynamic_code_dir.remove(&(module, name, arity));
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}
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#[inline]
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pub fn get_clause_subsection(&self, module: ClauseName, name: ClauseName, arity: usize)
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-> Option<DynamicPredicateInfo>
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{
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self.dynamic_code_dir.get(&(module, name, arity)).cloned()
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}
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#[inline]
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pub fn take_module(&mut self, name: ClauseName) -> Option<Module> {
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self.modules.remove(&name)
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}
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#[inline]
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pub fn insert_module(&mut self, module: Module) {
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self.modules.insert(module.module_decl.name.clone(), module);
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}
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|
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#[inline]
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pub(super) fn new() -> Self {
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IndexStore {
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atom_tbl: TabledData::new(Rc::new("user".to_string())),
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code_dir: CodeDir::new(),
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dynamic_code_dir: DynamicCodeDir::new(),
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global_variables: GlobalVarDir::new(),
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in_situ_code_dir: InSituCodeDir::new(),
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op_dir: default_op_dir(),
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modules: ModuleDir::new(),
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// parsing_stream: readline::parsing_stream(String::new())
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}
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}
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#[inline]
|
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pub(super) fn copy_and_swap(&mut self, other: &mut IndexStore) {
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self.code_dir = other.code_dir.clone();
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self.op_dir = other.op_dir.clone();
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mem::swap(&mut self.code_dir, &mut other.code_dir);
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mem::swap(&mut self.op_dir, &mut other.op_dir);
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mem::swap(&mut self.modules, &mut other.modules);
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}
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|
|
#[inline]
|
|
fn get_internal(&self, name: ClauseName, arity: usize, in_mod: ClauseName) -> Option<CodeIndex>
|
|
{
|
|
self.modules.get(&in_mod)
|
|
.and_then(|ref module| module.code_dir.get(&(name, arity)))
|
|
.cloned()
|
|
}
|
|
|
|
pub(super) fn get_cleaner_sites(&self) -> (usize, usize) {
|
|
let r_w_h = clause_name!("run_cleaners_with_handling");
|
|
let r_wo_h = clause_name!("run_cleaners_without_handling");
|
|
|
|
let non_iso = clause_name!("non_iso");
|
|
|
|
let r_w_h = self.get_internal(r_w_h, 0, non_iso.clone()).and_then(|item| item.local());
|
|
let r_wo_h = self.get_internal(r_wo_h, 1, non_iso).and_then(|item| item.local());
|
|
|
|
if let Some(r_w_h) = r_w_h {
|
|
if let Some(r_wo_h) = r_wo_h {
|
|
return (r_w_h, r_wo_h);
|
|
}
|
|
}
|
|
|
|
return (0, 0);
|
|
}
|
|
}
|
|
|
|
pub type CodeDir = BTreeMap<PredicateKey, CodeIndex>;
|
|
pub type TermDir = IndexMap<PredicateKey, (Predicate, VecDeque<TopLevel>)>;
|
|
|
|
#[derive(Clone, Copy, PartialEq, Eq, Ord, PartialOrd)]
|
|
pub enum CompileTimeHook {
|
|
GoalExpansion,
|
|
TermExpansion,
|
|
UserGoalExpansion,
|
|
UserTermExpansion
|
|
}
|
|
|
|
impl CompileTimeHook {
|
|
pub fn name(self) -> ClauseName {
|
|
match self {
|
|
CompileTimeHook::UserGoalExpansion
|
|
| CompileTimeHook::GoalExpansion => clause_name!("goal_expansion"),
|
|
CompileTimeHook::UserTermExpansion
|
|
| CompileTimeHook::TermExpansion => clause_name!("term_expansion")
|
|
}
|
|
}
|
|
|
|
#[inline]
|
|
pub fn arity(self) -> usize {
|
|
match self {
|
|
CompileTimeHook::UserGoalExpansion
|
|
| CompileTimeHook::GoalExpansion => 2,
|
|
CompileTimeHook::UserTermExpansion
|
|
| CompileTimeHook::TermExpansion => 2
|
|
}
|
|
}
|
|
|
|
#[inline]
|
|
pub fn user_scope(self) -> Self {
|
|
match self {
|
|
CompileTimeHook::UserGoalExpansion | CompileTimeHook::GoalExpansion =>
|
|
CompileTimeHook::UserGoalExpansion,
|
|
CompileTimeHook::UserTermExpansion | CompileTimeHook::TermExpansion =>
|
|
CompileTimeHook::UserTermExpansion,
|
|
}
|
|
}
|
|
|
|
#[inline]
|
|
pub fn has_module_scope(self) -> bool {
|
|
match self {
|
|
CompileTimeHook::UserTermExpansion | CompileTimeHook::UserGoalExpansion => false,
|
|
_ => true
|
|
}
|
|
}
|
|
}
|
|
|
|
pub enum RefOrOwned<'a, T: 'a> {
|
|
Borrowed(&'a T),
|
|
Owned(T)
|
|
}
|
|
|
|
impl<'a, T> RefOrOwned<'a, T> {
|
|
pub fn as_ref(&'a self) -> &'a T {
|
|
match self {
|
|
&RefOrOwned::Borrowed(r) => r,
|
|
&RefOrOwned::Owned(ref r) => r
|
|
}
|
|
}
|
|
|
|
pub fn to_owned(self) -> T
|
|
where T: Clone
|
|
{
|
|
match self {
|
|
RefOrOwned::Borrowed(item) => item.clone(),
|
|
RefOrOwned::Owned(item) => item
|
|
}
|
|
}
|
|
}
|