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Rename some index variables.
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Now that all indices have type `usize`, it makes sense to be more
consistent about their naming. This commit removes all uses of `i` in
favour of `index`.
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@nnethercote
nnethercote committed Sep 17, 2019
1 parent cf3a562 commit 7f6e160
Showing 1 changed file with 44 additions and 44 deletions.
88 changes: 44 additions & 44 deletions src/librustc_data_structures/obligation_forest/mod.rs
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Expand Up @@ -353,9 +353,9 @@ impl<O: ForestObligation> ObligationForest<O> {
/// Converts all remaining obligations to the given error.
pub fn to_errors<E: Clone>(&mut self, error: E) -> Vec<Error<O, E>> {
let mut errors = vec![];
for (i, node) in self.nodes.iter().enumerate() {
for (index, node) in self.nodes.iter().enumerate() {
if let NodeState::Pending = node.state.get() {
let backtrace = self.error_at(i);
let backtrace = self.error_at(index);
errors.push(Error {
error: error.clone(),
backtrace,
Expand Down Expand Up @@ -399,10 +399,10 @@ impl<O: ForestObligation> ObligationForest<O> {
let mut errors = vec![];
let mut stalled = true;

for i in 0..self.nodes.len() {
let node = &mut self.nodes[i];
for index in 0..self.nodes.len() {
let node = &mut self.nodes[index];

debug!("process_obligations: node {} == {:?}", i, node);
debug!("process_obligations: node {} == {:?}", index, node);

// `processor.process_obligation` can modify the predicate within
// `node.obligation`, and that predicate is the key used for
Expand All @@ -414,7 +414,7 @@ impl<O: ForestObligation> ObligationForest<O> {
_ => continue
};

debug!("process_obligations: node {} got result {:?}", i, result);
debug!("process_obligations: node {} got result {:?}", index, result);

match result {
ProcessResult::Unchanged => {
Expand All @@ -428,18 +428,18 @@ impl<O: ForestObligation> ObligationForest<O> {
for child in children {
let st = self.register_obligation_at(
child,
Some(i)
Some(index)
);
if let Err(()) = st {
// Error already reported - propagate it
// to our node.
self.error_at(i);
self.error_at(index);
}
}
}
ProcessResult::Error(err) => {
stalled = false;
let backtrace = self.error_at(i);
let backtrace = self.error_at(index);
errors.push(Error {
error: err,
backtrace,
Expand Down Expand Up @@ -483,14 +483,14 @@ impl<O: ForestObligation> ObligationForest<O> {

debug!("process_cycles()");

for (i, node) in self.nodes.iter().enumerate() {
for (index, node) in self.nodes.iter().enumerate() {
// For rustc-benchmarks/inflate-0.1.0 this state test is extremely
// hot and the state is almost always `Pending` or `Waiting`. It's
// a win to handle the no-op cases immediately to avoid the cost of
// the function call.
match node.state.get() {
NodeState::Waiting | NodeState::Pending | NodeState::Done | NodeState::Error => {},
_ => self.find_cycles_from_node(&mut stack, processor, i),
_ => self.find_cycles_from_node(&mut stack, processor, index),
}
}

Expand All @@ -500,19 +500,19 @@ impl<O: ForestObligation> ObligationForest<O> {
self.scratch.replace(stack);
}

fn find_cycles_from_node<P>(&self, stack: &mut Vec<usize>, processor: &mut P, i: usize)
fn find_cycles_from_node<P>(&self, stack: &mut Vec<usize>, processor: &mut P, index: usize)
where P: ObligationProcessor<Obligation=O>
{
let node = &self.nodes[i];
let node = &self.nodes[index];
match node.state.get() {
NodeState::OnDfsStack => {
let i = stack.iter().rposition(|n| *n == i).unwrap();
processor.process_backedge(stack[i..].iter().map(GetObligation(&self.nodes)),
let index = stack.iter().rposition(|&n| n == index).unwrap();
processor.process_backedge(stack[index..].iter().map(GetObligation(&self.nodes)),
PhantomData);
}
NodeState::Success => {
node.state.set(NodeState::OnDfsStack);
stack.push(i);
stack.push(index);
for &index in node.dependents.iter() {
self.find_cycles_from_node(stack, processor, index);
}
Expand All @@ -531,28 +531,28 @@ impl<O: ForestObligation> ObligationForest<O> {

/// Returns a vector of obligations for `p` and all of its
/// ancestors, putting them into the error state in the process.
fn error_at(&self, mut i: usize) -> Vec<O> {
fn error_at(&self, mut index: usize) -> Vec<O> {
let mut error_stack = self.scratch.replace(vec![]);
let mut trace = vec![];

loop {
let node = &self.nodes[i];
let node = &self.nodes[index];
node.state.set(NodeState::Error);
trace.push(node.obligation.clone());
if node.has_parent {
// The first dependent is the parent, which is treated
// specially.
error_stack.extend(node.dependents.iter().skip(1));
i = node.dependents[0];
index = node.dependents[0];
} else {
// No parent; treat all dependents non-specially.
error_stack.extend(node.dependents.iter());
break;
}
}

while let Some(i) = error_stack.pop() {
let node = &self.nodes[i];
while let Some(index) = error_stack.pop() {
let node = &self.nodes[index];
match node.state.get() {
NodeState::Error => continue,
_ => node.state.set(NodeState::Error),
Expand All @@ -568,8 +568,8 @@ impl<O: ForestObligation> ObligationForest<O> {
// This always-inlined function is for the hot call site.
#[inline(always)]
fn inlined_mark_neighbors_as_waiting_from(&self, node: &Node<O>) {
for &dependent in node.dependents.iter() {
self.mark_as_waiting_from(&self.nodes[dependent]);
for &index in node.dependents.iter() {
self.mark_as_waiting_from(&self.nodes[index]);
}
}

Expand Down Expand Up @@ -622,16 +622,16 @@ impl<O: ForestObligation> ObligationForest<O> {
// Now move all popped nodes to the end. Try to keep the order.
//
// LOOP INVARIANT:
// self.nodes[0..i - dead_nodes] are the first remaining nodes
// self.nodes[i - dead_nodes..i] are all dead
// self.nodes[i..] are unchanged
for i in 0..self.nodes.len() {
let node = &self.nodes[i];
// self.nodes[0..index - dead_nodes] are the first remaining nodes
// self.nodes[index - dead_nodes..index] are all dead
// self.nodes[index..] are unchanged
for index in 0..self.nodes.len() {
let node = &self.nodes[index];
match node.state.get() {
NodeState::Pending | NodeState::Waiting => {
if dead_nodes > 0 {
self.nodes.swap(i, i - dead_nodes);
node_rewrites[i] -= dead_nodes;
self.nodes.swap(index, index - dead_nodes);
node_rewrites[index] -= dead_nodes;
}
}
NodeState::Done => {
Expand All @@ -646,17 +646,17 @@ impl<O: ForestObligation> ObligationForest<O> {
} else {
self.done_cache.insert(node.obligation.as_predicate().clone());
}
node_rewrites[i] = nodes_len;
node_rewrites[index] = nodes_len;
dead_nodes += 1;
}
NodeState::Error => {
// We *intentionally* remove the node from the cache at this point. Otherwise
// tests must come up with a different type on every type error they
// check against.
self.waiting_cache.remove(node.obligation.as_predicate());
node_rewrites[i] = nodes_len;
node_rewrites[index] = nodes_len;
dead_nodes += 1;
self.insert_into_error_cache(i);
self.insert_into_error_cache(index);
}
NodeState::OnDfsStack | NodeState::Success => unreachable!()
}
Expand Down Expand Up @@ -697,30 +697,30 @@ impl<O: ForestObligation> ObligationForest<O> {
let nodes_len = node_rewrites.len();

for node in &mut self.nodes {
let mut i = 0;
while i < node.dependents.len() {
let new_i = node_rewrites[node.dependents[i]];
if new_i >= nodes_len {
node.dependents.swap_remove(i);
if i == 0 && node.has_parent {
let mut index = 0;
while index < node.dependents.len() {
let new_index = node_rewrites[node.dependents[index]];
if new_index >= nodes_len {
node.dependents.swap_remove(index);
if index == 0 && node.has_parent {
// We just removed the parent.
node.has_parent = false;
}
} else {
node.dependents[i] = new_i;
i += 1;
node.dependents[index] = new_index;
index += 1;
}
}
}

// This updating of `self.waiting_cache` is necessary because the
// removal of nodes within `compress` can fail. See above.
self.waiting_cache.retain(|_predicate, index| {
let new_i = node_rewrites[*index];
if new_i >= nodes_len {
let new_index = node_rewrites[*index];
if new_index >= nodes_len {
false
} else {
*index = new_i;
*index = new_index;
true
}
});
Expand Down

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