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slight polishing up, bug fixes

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This commit is contained in:
Mark Thom
2017-02-02 16:09:18 -07:00
parent 23fc50417f
commit 648b7d09fe
4 changed files with 93 additions and 72 deletions
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11
src/l1/ast.rs
View File

@@ -87,6 +87,17 @@ pub enum Addr {
RegNum(usize)
}
#[derive(Clone)]
pub enum HeapCellValue {
NamedStr(usize, Atom),
Ref(usize),
Str(usize),
}
pub type Heap = Vec<HeapCellValue>;
pub type Registers = Vec<HeapCellValue>;
impl Term {
pub fn subterms(&self) -> usize {
match self {

5
src/l1/codegen.rs
View File

@@ -255,8 +255,7 @@ fn var_term<'a, Target>(tm: &mut TermMarker<'a>,
}
}
fn subterm_to_instr<'a, Target>(tm: &mut TermMarker<'a>,
subterm: &'a Term)
fn subterm_to_instr<'a, Target>(tm: &mut TermMarker<'a>, subterm: &'a Term)
-> Target
where Target: CompilationTarget<'a>
{
@@ -302,7 +301,7 @@ pub fn compile_fact(term: &Term) -> CompiledFact {
compiled_fact
}
pub fn compile_query(term: &Term) -> CompiledQuery {
pub fn compile_query<'a>(term: &'a Term) -> CompiledQuery {
let mut compiled_query = compile_target(term);
if let &Term::Clause(_, ref atom, ref terms) = term {

107
src/l1/machine.rs
View File

@@ -1,34 +1,25 @@
use l1::ast::{Addr, Atom, CompiledFact, FactInstruction, QueryInstruction};
use l1::ast::{Addr, Atom, CompiledFact, CompiledQuery,
FactInstruction, Heap, HeapCellValue, QueryInstruction,
Registers};
use std::collections::HashMap;
use std::vec::Vec;
#[derive(Clone)]
enum HeapCell {
NamedStr(usize, Atom),
Ref(usize),
Str(usize),
}
#[derive(Clone, Copy)]
enum MachineMode {
Read,
Write
}
type Heap = Vec<HeapCell>;
type Registers = Vec<HeapCell>;
pub struct Machine {
h : usize,
s : usize,
p : usize,
pub fail : bool,
code : CompiledFact,
code_dir : HashMap<(Atom, usize), usize>,
fail : bool,
heap : Heap,
mode : MachineMode,
pub code_dir : HashMap<(Atom, usize), usize>,
pub code : CompiledFact,
registers : Registers
}
@@ -37,15 +28,27 @@ impl Machine {
Machine { h : 0,
s : 0,
p : 0,
code : Vec::new(),
code_dir : HashMap::new(),
fail : false,
heap : Vec::with_capacity(256),
mode : MachineMode::Write,
code_dir : HashMap::new(),
code : Vec::new(),
registers : vec![HeapCell::Ref(0); 32] }
registers : vec![HeapCellValue::Ref(0); 32] }
}
fn lookup(&self, a: Addr) -> &HeapCell {
pub fn add_fact(&mut self, mut fact: CompiledFact, name: Atom, arity: usize)
{
let index = self.code.len();
self.code.append(&mut fact);
self.code_dir.insert((name, arity), index);
}
pub fn failed(&self) -> bool {
self.fail
}
fn lookup(&self, a: Addr) -> &HeapCellValue {
match a {
Addr::HeapCell(hc) => &self.heap[hc],
Addr::RegNum(reg) => &self.registers[reg]
@@ -56,12 +59,15 @@ impl Machine {
let mut a = a;
loop {
if let &HeapCell::Ref(value) = self.lookup(a) {
if let &HeapCellValue::Ref(value) = self.lookup(a) {
if let Addr::HeapCell(av) = a {
if value != av {
a = Addr::HeapCell(value);
continue;
}
} else {
a = Addr::HeapCell(value);
continue;
}
}
@@ -69,21 +75,21 @@ impl Machine {
};
}
fn is_unbound(hc: &HeapCell, index: usize) -> bool {
fn is_unbound(hc: &HeapCellValue, index: usize) -> bool {
match hc {
&HeapCell::Ref(r) => r == index,
&HeapCellValue::Ref(r) => r == index,
_ => false
}
}
//TODO: try to compress this function. currently it is dog shit.
//TODO: try to compress this function.
fn bind(&mut self, a: Addr, val: usize) {
let mut a = a;
loop {
match a {
Addr::RegNum(reg) => {
if let HeapCell::Ref(hc) = self.registers[reg] {
if let HeapCellValue::Ref(hc) = self.registers[reg] {
a = Addr::HeapCell(hc);
} else if Machine::is_unbound(&self.heap[val], val) {
self.heap[val] = self.registers[reg].clone();
@@ -94,11 +100,11 @@ impl Machine {
}
},
Addr::HeapCell(hc) if Machine::is_unbound(&self.heap[hc], hc) => {
self.heap[hc] = HeapCell::Ref(val);
self.heap[hc] = HeapCellValue::Ref(val);
break;
},
Addr::HeapCell(hc) if Machine::is_unbound(&self.heap[val], val) => {
self.heap[val] = HeapCell::Ref(hc);
self.heap[val] = HeapCellValue::Ref(hc);
break;
},
_ => {
@@ -110,7 +116,7 @@ impl Machine {
}
fn unify(&mut self, a1: Addr, a2: Addr) {
let mut pdl : Vec<Addr> = vec![a1, a2];
let mut pdl = vec![a1, a2];
self.fail = false;
@@ -120,16 +126,16 @@ impl Machine {
if d1 != d2 {
match (self.lookup(d1), self.lookup(d2)) {
(&HeapCell::Ref(hc), _) =>
(&HeapCellValue::Ref(hc), _) =>
self.bind(d2, hc),
(_, &HeapCell::Ref(hc)) =>
(_, &HeapCellValue::Ref(hc)) =>
self.bind(d1, hc),
(&HeapCell::Str(a1), &HeapCell::Str(a2)) => {
(&HeapCellValue::Str(a1), &HeapCellValue::Str(a2)) => {
let r1 = &self.heap[a1];
let r2 = &self.heap[a2];
if let &HeapCell::NamedStr(n1, ref f1) = r1 {
if let &HeapCell::NamedStr(n2, ref f2) = r2 {
if let &HeapCellValue::NamedStr(n1, ref f1) = r1 {
if let &HeapCellValue::NamedStr(n2, ref f2) = r2 {
if n1 == n2 && *f1 == *f2 {
for i in 1 .. n1 {
pdl.push(Addr::HeapCell(a1 + i));
@@ -162,12 +168,23 @@ impl Machine {
}
}
pub fn execute_query_instr<'a, 'b: 'a>(&'a mut self, instr: &'b QueryInstruction) {
pub fn execute_query(&mut self, query: &CompiledQuery) {
for instr in query {
self.execute_query_instr(instr);
if self.fail {
break;
}
}
}
fn execute_query_instr<'a, 'b: 'a>(&'a mut self, instr: &'b QueryInstruction) {
match instr {
&QueryInstruction::Call(ref name, arity) => {
// why is Option<&T> not Deref?!?!?
let compiled_fact_index =
self.code_dir.get(&(name.clone(), arity)).map(|index| *index);
self.code_dir.get(&(name.clone(), arity))
.map(|index| *index);
match compiled_fact_index {
Some(compiled_fact_index) => {
@@ -178,8 +195,8 @@ impl Machine {
};
}
&QueryInstruction::PutStructure(_, ref name, arity, reg) => {
self.heap.push(HeapCell::Str(self.h + 1));
self.heap.push(HeapCell::NamedStr(arity, name.clone()));
self.heap.push(HeapCellValue::Str(self.h + 1));
self.heap.push(HeapCellValue::NamedStr(arity, name.clone()));
self.registers[reg] = self.heap[self.h].clone();
@@ -188,7 +205,7 @@ impl Machine {
&QueryInstruction::PutValue(arg, norm) =>
self.registers[arg] = self.registers[norm].clone(),
&QueryInstruction::PutVariable(arg, norm) => {
self.heap.push(HeapCell::Ref(self.h));
self.heap.push(HeapCellValue::Ref(self.h));
self.registers[norm] = self.heap[self.h].clone();
self.registers[arg] = self.heap[self.h].clone();
@@ -196,7 +213,7 @@ impl Machine {
self.h += 1;
},
&QueryInstruction::SetVariable(reg) => {
self.heap.push(HeapCell::Ref(self.h));
self.heap.push(HeapCellValue::Ref(self.h));
self.registers[reg] = self.heap[self.h].clone();
self.h += 1;
@@ -215,10 +232,10 @@ impl Machine {
let addr = self.deref(Addr::RegNum(reg));
match self.lookup(addr) {
&HeapCell::Str(a) => {
&HeapCellValue::Str(a) => {
let result = &self.heap[a];
if let &HeapCell::NamedStr(named_arity, ref named_str) = result {
if let &HeapCellValue::NamedStr(named_arity, ref named_str) = result {
if arity == named_arity && *name == *named_str {
self.s = a + 1;
self.mode = MachineMode::Read;
@@ -227,9 +244,9 @@ impl Machine {
}
}
},
&HeapCell::Ref(r) => {
self.heap.push(HeapCell::Str(self.h + 1));
self.heap.push(HeapCell::NamedStr(arity, name));
&HeapCellValue::Ref(r) => {
self.heap.push(HeapCellValue::Str(self.h + 1));
self.heap.push(HeapCellValue::NamedStr(arity, name));
let h = self.h;
@@ -251,7 +268,7 @@ impl Machine {
match self.mode {
MachineMode::Read => self.registers[reg] = self.heap[self.s].clone(),
MachineMode::Write => {
self.heap.push(HeapCell::Ref(self.h));
self.heap.push(HeapCellValue::Ref(self.h));
self.registers[reg] = self.heap[self.h].clone();
self.h += 1;
}
@@ -285,6 +302,6 @@ impl Machine {
self.fail = false;
self.heap = Vec::with_capacity(256);
self.mode = MachineMode::Write;
self.registers = vec![HeapCell::Ref(0); 32];
self.registers = vec![HeapCellValue::Ref(0); 32];
}
}

18
src/main.rs
View File

@@ -27,24 +27,18 @@ fn l1_repl() {
match result {
Ok(TopLevel::Fact(fact)) => {
let mut compiled_fact = compile_fact(&fact);
let index = ms.code.len();
let name = fact.name().to_owned();
let arity = fact.arity();
let fact = compile_fact(&fact);
ms.code.append(&mut compiled_fact);
ms.code_dir.insert((fact.name().clone(), fact.arity()), index);
ms.add_fact(fact, name, arity);
},
Ok(TopLevel::Query(query)) => {
let compiled_query = compile_query(&query);
for instruction in &compiled_query {
ms.execute_query_instr(instruction);
ms.execute_query(&compiled_query);
if ms.fail {
break;
}
}
if ms.fail {
if ms.failed() {
println!("no");
} else {
println!("yes");