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optimized up to chapter 6

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This commit is contained in:
Mark Thom
2017-04-09 19:12:36 -06:00
parent d2cf8626a1
commit 19ee43e186
12 changed files with 1132 additions and 726 deletions
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170
src/prolog/machine.rs
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@@ -19,6 +19,7 @@ struct MachineState {
s: usize,
p: CodePtr,
b: usize,
b0: usize,
e: usize,
num_of_args: usize,
cp: CodePtr,
@@ -82,7 +83,7 @@ impl Machine {
pub fn add_fact(&mut self, fact: &Term, mut code: Code) {
if let Some(name) = fact.name() {
let p = self.code.len();
let p = self.code.len();
let arity = fact.arity();
self.code.append(&mut code);
@@ -121,6 +122,8 @@ impl Machine {
match instr {
&Line::Choice(ref choice_instr) =>
self.ms.execute_choice_instr(choice_instr),
&Line::Cut(ref cut_instr) =>
self.ms.execute_cut_instr(cut_instr),
&Line::Control(ref control_instr) =>
self.ms.execute_ctrl_instr(&self.code_dir, control_instr),
&Line::Fact(ref fact) => {
@@ -132,7 +135,7 @@ impl Machine {
self.ms.execute_fact_instr(&fact_instr);
}
self.ms.p += 1;
},
},
&Line::Indexing(ref indexing_instr) =>
self.ms.execute_indexing_instr(&indexing_instr),
&Line::IndexedChoice(ref choice_instr) =>
@@ -146,21 +149,29 @@ impl Machine {
self.ms.execute_query_instr(&query_instr);
}
self.ms.p += 1;
}
}
}
if self.failed() {
let p = self.ms
.or_stack
.top()
.map(|fr| fr.bp)
.unwrap_or_default();
let b0 = self.ms
.or_stack
.top()
.map(|fr| fr.b0)
.unwrap_or(0);
let p = if self.ms.b > 0 {
let b = self.ms.b - 1;
self.ms.or_stack[b].bp
} else {
CodePtr::TopLevel
};
if let CodePtr::TopLevel = p {
return false;
} else {
self.ms.fail = false;
self.ms.p = p;
self.ms.b0 = b0;
}
}
@@ -267,7 +278,11 @@ impl Machine {
pub fn continue_query(&mut self) -> EvalResult
{
if !self.or_stack_is_empty() {
let b = self.ms.b;
if self.ms.b == 0 {
return EvalResult::QueryFailure;
}
let b = self.ms.b - 1;
self.ms.p = self.ms.or_stack[b].bp;
let succeeded = if let CodePtr::DirEntry(p) = self.ms.p {
@@ -286,6 +301,13 @@ impl Machine {
}
}
#[allow(dead_code)]
pub fn clear(&mut self) {
self.reset();
self.code.clear();
self.code_dir.clear();
}
pub fn reset(&mut self) {
self.ms.reset();
}
@@ -297,6 +319,7 @@ impl MachineState {
s: 0,
p: CodePtr::TopLevel,
b: 0,
b0: 0,
e: 0,
num_of_args: 0,
cp: CodePtr::TopLevel,
@@ -419,7 +442,12 @@ impl MachineState {
Ref::StackCell(fr, _) => {
let fr_gi = self.and_stack[fr].global_index;
let b_gi = if !self.or_stack.is_empty() {
self.or_stack[self.b].global_index
if self.b > 0 {
let b = self.b - 1;
self.or_stack[b].global_index
} else {
0
}
} else {
0
};
@@ -443,6 +471,48 @@ impl MachineState {
}
}
fn tidy_trail(&mut self) {
if self.b == 0 {
return;
}
let b = self.b - 1;
let mut i = self.or_stack[b].tr;
while i < self.tr {
let tr_i = self.trail[i];
let hb = self.hb;
match tr_i {
Ref::HeapCell(tr_i) =>
if tr_i < hb { //|| ((h < tr_i) && tr_i < b) {
i += 1;
} else {
let tr = self.tr;
let val = self.trail[tr - 1];
self.trail[i] = val;
},
Ref::StackCell(fr, _) => {
let b = self.b - 1;
let fr_gi = self.and_stack[fr].global_index;
let b_gi = if !self.or_stack.is_empty() {
self.or_stack[b].global_index
} else {
0
};
if fr_gi < b_gi {
i += 1;
} else {
let tr = self.tr;
let val = self.trail[tr - 1];
self.trail[i] = val;
}
}
};
}
}
fn execute_fact_instr(&mut self, instr: &FactInstruction) {
match instr {
&FactInstruction::GetConstant(_, ref constant, reg) => {
@@ -703,12 +773,12 @@ impl MachineState {
match offset {
0 => self.fail = true,
o => self.p += o
};
o => self.p += o
};
}
};
}
fn execute_query_instr(&mut self, instr: &QueryInstruction) {
match instr {
&QueryInstruction::PutConstant(_, ref constant, reg) =>
@@ -821,6 +891,7 @@ impl MachineState {
Some(compiled_tl_index) => {
self.cp = self.p + 1;
self.num_of_args = arity;
self.b0 = self.b;
self.p = CodePtr::DirEntry(compiled_tl_index);
},
None => self.fail = true
@@ -841,7 +912,8 @@ impl MachineState {
match compiled_tl_index {
Some(compiled_tl_index) => {
self.num_of_args = arity;
self.p = CodePtr::DirEntry(compiled_tl_index);
self.b0 = self.b;
self.p = CodePtr::DirEntry(compiled_tl_index);
},
None => self.fail = true
};
@@ -865,10 +937,11 @@ impl MachineState {
self.p + 1,
self.tr,
self.h,
self.b0,
self.num_of_args);
self.b = self.or_stack.len() - 1;
let b = self.b;
self.b = self.or_stack.len();
let b = self.b - 1;
for i in 1 .. n + 1 {
self.or_stack[b][i] = self.registers[i].clone();
@@ -878,7 +951,7 @@ impl MachineState {
self.p += l;
},
&IndexedChoiceInstruction::Retry(l) => {
let b = self.b;
let b = self.b - 1;
let n = self.or_stack[b].num_args();
for i in 1 .. n + 1 {
@@ -905,7 +978,7 @@ impl MachineState {
self.p += l;
},
&IndexedChoiceInstruction::Trust(l) => {
let b = self.b;
let b = self.b - 1;
let n = self.or_stack[b].num_args();
for i in 1 .. n + 1 {
@@ -935,10 +1008,10 @@ impl MachineState {
}
};
}
fn execute_choice_instr(&mut self, instr: &ChoiceInstruction)
{
match instr {
match instr {
&ChoiceInstruction::TryMeElse(offset) => {
let n = self.num_of_args;
let num_frames = self.num_frames();
@@ -950,10 +1023,11 @@ impl MachineState {
self.p + offset,
self.tr,
self.h,
self.b0,
self.num_of_args);
self.b = self.or_stack.len() - 1;
let b = self.b;
self.b = self.or_stack.len();
let b = self.b - 1;
for i in 1 .. n + 1 {
self.or_stack[b][i] = self.registers[i].clone();
@@ -961,9 +1035,9 @@ impl MachineState {
self.hb = self.h;
self.p += 1;
},
},
&ChoiceInstruction::RetryMeElse(offset) => {
let b = self.b;
let b = self.b - 1;
let n = self.or_stack[b].num_args();
for i in 1 .. n + 1 {
@@ -990,7 +1064,7 @@ impl MachineState {
self.p += 1;
},
&ChoiceInstruction::TrustMe => {
let b = self.b;
let b = self.b - 1;
let n = self.or_stack[b].num_args();
for i in 1 .. n + 1 {
@@ -1021,11 +1095,55 @@ impl MachineState {
}
}
fn execute_cut_instr(&mut self, instr: &CutInstruction) {
match instr {
&CutInstruction::Cut(ref term) => {
let b = self.b;
let e = self.e;
let b0 = self.and_stack[e].b0; // STACK[E+2+1]
if b > b0 {
self.b = b0;
self.tidy_trail();
}
if let &Terminal::Terminal = term {
self.p = CodePtr::TopLevel;
} else {
self.p += 1;
}
},
&CutInstruction::GetLevel => {
let b0 = self.b0;
let e = self.e;
self.and_stack[e].b0 = b0;
self.p += 1;
},
&CutInstruction::NeckCut(ref term) => {
let b = self.b;
let b0 = self.b0;
if b > b0 {
self.b = b0;
self.tidy_trail();
}
if let &Terminal::Terminal = term {
self.p = CodePtr::TopLevel;
} else {
self.p += 1;
}
}
}
}
fn reset(&mut self) {
self.h = 0;
self.hb = 0;
self.e = 0;
self.b = 0;
self.b0 = 0;
self.s = 0;
self.tr = 0;
self.p = CodePtr::TopLevel;
@@ -1039,5 +1157,5 @@ impl MachineState {
self.and_stack.clear();
self.or_stack.clear();
self.registers = vec![Addr::HeapCell(0); 64];
}
}
}