rishi/scryer-prolog
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use references when executing instructions, not moves.

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This commit is contained in:
Mark Thom
2016-12-01 17:33:02 -07:00
parent d46197f1fd
commit 2874c172ba
3 changed files with 14 additions and 14 deletions
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1
src/l0/ast.rs
View File

@@ -17,7 +17,6 @@ pub enum Term {
Var(Var) Var(Var)
} }
#[derive(Clone)]
pub enum MachineInstruction { pub enum MachineInstruction {
GetStructure(Atom, usize, usize), GetStructure(Atom, usize, usize),
PutStructure(Atom, usize, usize), PutStructure(Atom, usize, usize),

20
src/l0/machine.rs
View File

@@ -112,9 +112,9 @@ impl MachineState {
} }
} }
pub fn execute(&mut self, instr: MachineInstruction) { pub fn execute<'a, 'b : 'a>(&'a mut self, instr: &'b MachineInstruction) {
match instr { match instr {
MachineInstruction::GetStructure(name, arity, reg) => { &MachineInstruction::GetStructure(ref name, arity, reg) => {
let addr = self.deref(Addr::RegNum(reg)); let addr = self.deref(Addr::RegNum(reg));
match self.lookup(addr) { match self.lookup(addr) {
@@ -122,7 +122,7 @@ impl MachineState {
let result = &self.heap[a]; let result = &self.heap[a];
if let &HeapCell::NamedStr(named_arity, ref named_str) = result { if let &HeapCell::NamedStr(named_arity, ref named_str) = result {
if arity == named_arity && name == *named_str { if arity == named_arity && *name == *named_str {
self.s = a + 1; self.s = a + 1;
self.mode = MachineMode::Read; self.mode = MachineMode::Read;
} else { } else {
@@ -132,7 +132,7 @@ impl MachineState {
}, },
&HeapCell::Ref(reg) => { &HeapCell::Ref(reg) => {
self.heap.push(HeapCell::Str(self.h + 1)); self.heap.push(HeapCell::Str(self.h + 1));
self.heap.push(HeapCell::NamedStr(arity, name)); self.heap.push(HeapCell::NamedStr(arity, name.clone()));
let h = self.h; let h = self.h;
@@ -146,25 +146,25 @@ impl MachineState {
} }
}; };
}, },
MachineInstruction::PutStructure(name, arity, reg) => { &MachineInstruction::PutStructure(ref name, arity, reg) => {
self.heap.push(HeapCell::Str(self.h + 1)); self.heap.push(HeapCell::Str(self.h + 1));
self.heap.push(HeapCell::NamedStr(arity, name)); self.heap.push(HeapCell::NamedStr(arity, name.clone()));
self.registers[reg] = self.heap[self.h].clone(); self.registers[reg] = self.heap[self.h].clone();
self.h += 2; self.h += 2;
}, },
MachineInstruction::SetVariable(reg) => { &MachineInstruction::SetVariable(reg) => {
self.heap.push(HeapCell::Ref(self.h)); self.heap.push(HeapCell::Ref(self.h));
self.registers[reg] = self.heap[self.h].clone(); self.registers[reg] = self.heap[self.h].clone();
self.h += 1; self.h += 1;
}, },
MachineInstruction::SetValue(reg) => { &MachineInstruction::SetValue(reg) => {
self.heap.push(self.registers[reg].clone()); self.heap.push(self.registers[reg].clone());
self.h += 1; self.h += 1;
}, },
MachineInstruction::UnifyVariable(reg) => { &MachineInstruction::UnifyVariable(reg) => {
match self.mode { match self.mode {
MachineMode::Read => self.registers[reg] = self.heap[self.s].clone(), MachineMode::Read => self.registers[reg] = self.heap[self.s].clone(),
MachineMode::Write => { MachineMode::Write => {
@@ -176,7 +176,7 @@ impl MachineState {
self.s += 1; self.s += 1;
}, },
MachineInstruction::UnifyValue(reg) => { &MachineInstruction::UnifyValue(reg) => {
let s = self.s; let s = self.s;
match self.mode { match self.mode {

7
src/main.rs
View File

@@ -40,14 +40,14 @@ fn l0_repl<'a>() {
println!("Program stored."); println!("Program stored.");
}, },
Ok(TopLevel::Query(query)) => { Ok(TopLevel::Query(query)) => {
if let Some(program) = ms.program.clone().take() { if let Some(program) = ms.program.take() {
let query = compile_query(&query); let query = compile_query(&query);
for instruction in query { for instruction in &query {
ms.execute(instruction); ms.execute(instruction);
} }
for instruction in program { for instruction in &program {
ms.execute(instruction); ms.execute(instruction);
if ms.fail { if ms.fail {
@@ -62,6 +62,7 @@ fn l0_repl<'a>() {
} }
ms.reset_heap(); ms.reset_heap();
ms.program = Some(program);
} else { } else {
println!("No program to speak of."); println!("No program to speak of.");
} }