Rollup merge of #57719 - nnethercote:expand_node-FIDDLING, r=nikomatsakis
Tweak `expand_node`
These commits speed up the `unicode_normalization` benchmark a little.
diff --git a/src/librustc/infer/lexical_region_resolve/mod.rs b/src/librustc/infer/lexical_region_resolve/mod.rs
index 39ce8cc..545192a 100644
--- a/src/librustc/infer/lexical_region_resolve/mod.rs
+++ b/src/librustc/infer/lexical_region_resolve/mod.rs
@@ -186,34 +186,39 @@
}
fn expansion(&self, var_values: &mut LexicalRegionResolutions<'tcx>) {
- self.iterate_until_fixed_point("Expansion", |constraint, origin| {
- debug!("expansion: constraint={:?} origin={:?}", constraint, origin);
- match *constraint {
+ self.iterate_until_fixed_point("Expansion", |constraint| {
+ debug!("expansion: constraint={:?}", constraint);
+ let (a_region, b_vid, b_data, retain) = match *constraint {
Constraint::RegSubVar(a_region, b_vid) => {
let b_data = var_values.value_mut(b_vid);
- (self.expand_node(a_region, b_vid, b_data), false)
+ (a_region, b_vid, b_data, false)
}
Constraint::VarSubVar(a_vid, b_vid) => match *var_values.value(a_vid) {
- VarValue::ErrorValue => (false, false),
+ VarValue::ErrorValue => return (false, false),
VarValue::Value(a_region) => {
- let b_node = var_values.value_mut(b_vid);
- let changed = self.expand_node(a_region, b_vid, b_node);
- let retain = match *b_node {
+ let b_data = var_values.value_mut(b_vid);
+ let retain = match *b_data {
VarValue::Value(ReStatic) | VarValue::ErrorValue => false,
_ => true
};
- (changed, retain)
+ (a_region, b_vid, b_data, retain)
}
},
Constraint::RegSubReg(..) | Constraint::VarSubReg(..) => {
// These constraints are checked after expansion
// is done, in `collect_errors`.
- (false, false)
+ return (false, false)
}
- }
+ };
+
+ let changed = self.expand_node(a_region, b_vid, b_data);
+ (changed, retain)
})
}
+ // This function is very hot in some workloads. There's a single callsite
+ // so always inlining is ok even though it's large.
+ #[inline(always)]
fn expand_node(
&self,
a_region: Region<'tcx>,
@@ -722,18 +727,17 @@
}
fn iterate_until_fixed_point<F>(&self, tag: &str, mut body: F)
- where
- F: FnMut(&Constraint<'tcx>, &SubregionOrigin<'tcx>) -> (bool, bool),
+ where F: FnMut(&Constraint<'tcx>) -> (bool, bool),
{
- let mut constraints: SmallVec<[_; 16]> = self.data.constraints.iter().collect();
+ let mut constraints: SmallVec<[_; 16]> = self.data.constraints.keys().collect();
let mut iteration = 0;
let mut changed = true;
while changed {
changed = false;
iteration += 1;
debug!("---- {} Iteration {}{}", "#", tag, iteration);
- constraints.retain(|(constraint, origin)| {
- let (edge_changed, retain) = body(constraint, origin);
+ constraints.retain(|constraint| {
+ let (edge_changed, retain) = body(constraint);
if edge_changed {
debug!("Updated due to constraint {:?}", constraint);
changed = true;
