diff --git a/src/librustc_mir/build/block.rs b/src/librustc_mir/build/block.rs
index 7353ca9285ddb..aceed09757e7e 100644
--- a/src/librustc_mir/build/block.rs
+++ b/src/librustc_mir/build/block.rs
@@ -33,8 +33,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
this.ast_block_stmts(destination, block, span, stmts, expr,
safety_mode)
});
- this.cfg.terminate(unpack!(block_exit), source_info,
- TerminatorKind::Goto { target: exit_block });
+ this.cfg.goto(unpack!(block_exit), source_info, exit_block);
exit_block.unit()
} else {
this.ast_block_stmts(destination, block, span, stmts, expr,
diff --git a/src/librustc_mir/build/cfg.rs b/src/librustc_mir/build/cfg.rs
index 6bd8d2f7c0792..0e685486c3f99 100644
--- a/src/librustc_mir/build/cfg.rs
+++ b/src/librustc_mir/build/cfg.rs
@@ -85,4 +85,9 @@ impl<'tcx> CFG<'tcx> {
kind,
});
}
+
+ /// In the `origin` block, push a `goto -> target` terminator.
+ pub fn goto(&mut self, origin: BasicBlock, source_info: SourceInfo, target: BasicBlock) {
+ self.terminate(origin, source_info, TerminatorKind::Goto { target })
+ }
}
diff --git a/src/librustc_mir/build/expr/into.rs b/src/librustc_mir/build/expr/into.rs
index 608415408e35c..a9fa7cfa04a89 100644
--- a/src/librustc_mir/build/expr/into.rs
+++ b/src/librustc_mir/build/expr/into.rs
@@ -140,17 +140,9 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
},
);
- this.cfg.terminate(
- true_block,
- source_info,
- TerminatorKind::Goto { target: join_block },
- );
- this.cfg.terminate(
- false_block,
- source_info,
- TerminatorKind::Goto { target: join_block },
- );
-
+ // Link up both branches:
+ this.cfg.goto(true_block, source_info, join_block);
+ this.cfg.goto(false_block, source_info, join_block);
join_block.unit()
}
ExprKind::Loop { body } => {
@@ -167,12 +159,8 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
let loop_block = this.cfg.start_new_block();
let exit_block = this.cfg.start_new_block();
- // start the loop
- this.cfg.terminate(
- block,
- source_info,
- TerminatorKind::Goto { target: loop_block },
- );
+ // Start the loop.
+ this.cfg.goto(block, source_info, loop_block);
this.in_breakable_scope(
Some(loop_block),
@@ -196,11 +184,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
let tmp = this.get_unit_temp();
// Execute the body, branching back to the test.
let body_block_end = unpack!(this.into(&tmp, body_block, body));
- this.cfg.terminate(
- body_block_end,
- source_info,
- TerminatorKind::Goto { target: loop_block },
- );
+ this.cfg.goto(body_block_end, source_info, loop_block);
},
);
exit_block.unit()
diff --git a/src/librustc_mir/build/matches/mod.rs b/src/librustc_mir/build/matches/mod.rs
index bf0b2439c00b5..6869930509cbe 100644
--- a/src/librustc_mir/build/matches/mod.rs
+++ b/src/librustc_mir/build/matches/mod.rs
@@ -26,6 +26,7 @@ mod simplify;
mod test;
mod util;
+use itertools::Itertools;
use std::convert::TryFrom;
impl<'a, 'tcx> Builder<'a, 'tcx> {
@@ -258,11 +259,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
scrutinee_span,
match_scope,
);
- this.cfg.terminate(
- binding_end,
- source_info,
- TerminatorKind::Goto { target: arm_block },
- );
+ this.cfg.goto(binding_end, source_info, arm_block);
}
}
@@ -278,11 +275,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
let end_block = self.cfg.start_new_block();
for arm_block in arm_end_blocks {
- self.cfg.terminate(
- unpack!(arm_block),
- outer_source_info,
- TerminatorKind::Goto { target: end_block },
- );
+ self.cfg.goto(unpack!(arm_block), outer_source_info, end_block);
}
self.source_scope = outer_source_info.scope;
@@ -822,9 +815,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
);
let (matched_candidates, unmatched_candidates) = candidates.split_at_mut(fully_matched);
- let block: BasicBlock;
-
- if !matched_candidates.is_empty() {
+ let block: BasicBlock = if !matched_candidates.is_empty() {
let otherwise_block = self.select_matched_candidates(
matched_candidates,
start_block,
@@ -832,35 +823,26 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
);
if let Some(last_otherwise_block) = otherwise_block {
- block = last_otherwise_block
+ last_otherwise_block
} else {
// Any remaining candidates are unreachable.
if unmatched_candidates.is_empty() {
return;
}
- block = self.cfg.start_new_block();
- };
+ self.cfg.start_new_block()
+ }
} else {
- block = *start_block.get_or_insert_with(|| self.cfg.start_new_block());
- }
+ *start_block.get_or_insert_with(|| self.cfg.start_new_block())
+ };
// If there are no candidates that still need testing, we're
// done. Since all matches are exhaustive, execution should
// never reach this point.
if unmatched_candidates.is_empty() {
let source_info = self.source_info(span);
- if let Some(otherwise) = otherwise_block {
- self.cfg.terminate(
- block,
- source_info,
- TerminatorKind::Goto { target: otherwise },
- );
- } else {
- self.cfg.terminate(
- block,
- source_info,
- TerminatorKind::Unreachable,
- )
+ match otherwise_block {
+ Some(otherwise) => self.cfg.goto(block, source_info, otherwise),
+ None => self.cfg.terminate(block, source_info, TerminatorKind::Unreachable),
}
return;
}
@@ -885,7 +867,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
/// ...
///
/// We generate real edges from:
- /// * `block` to the prebinding_block of the first pattern,
+ /// * `start_block` to the `prebinding_block` of the first pattern,
/// * the otherwise block of the first pattern to the second pattern,
/// * the otherwise block of the third pattern to the a block with an
/// Unreachable terminator.
@@ -948,32 +930,25 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
let first_candidate = &reachable_candidates[0];
let first_prebinding_block = first_candidate.pre_binding_block;
+ // `goto -> first_prebinding_block` from the `start_block` if there is one.
if let Some(start_block) = *start_block {
let source_info = self.source_info(first_candidate.span);
- self.cfg.terminate(
- start_block,
- source_info,
- TerminatorKind::Goto { target: first_prebinding_block },
- );
+ self.cfg.goto(start_block, source_info, first_prebinding_block);
} else {
*start_block = Some(first_prebinding_block);
}
- for window in reachable_candidates.windows(2) {
- if let [first_candidate, second_candidate] = window {
- let source_info = self.source_info(first_candidate.span);
- if let Some(otherwise_block) = first_candidate.otherwise_block {
- self.false_edges(
- otherwise_block,
- second_candidate.pre_binding_block,
- first_candidate.next_candidate_pre_binding_block,
- source_info,
- );
- } else {
- bug!("candidate other than the last has no guard");
- }
+ for (first_candidate, second_candidate) in reachable_candidates.iter().tuple_windows() {
+ let source_info = self.source_info(first_candidate.span);
+ if let Some(otherwise_block) = first_candidate.otherwise_block {
+ self.false_edges(
+ otherwise_block,
+ second_candidate.pre_binding_block,
+ first_candidate.next_candidate_pre_binding_block,
+ source_info,
+ );
} else {
- bug!("<[_]>::windows returned incorrectly sized window");
+ bug!("candidate other than the last has no guard");
}
}
@@ -992,8 +967,8 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
}
}
- let last_candidate = reachable_candidates.last().unwrap();
+ let last_candidate = reachable_candidates.last().unwrap();
if let Some(otherwise) = last_candidate.otherwise_block {
let source_info = self.source_info(last_candidate.span);
let block = self.cfg.start_new_block();
diff --git a/src/librustc_mir/build/matches/test.rs b/src/librustc_mir/build/matches/test.rs
index e320811ca0556..bdc1bdd5b9855 100644
--- a/src/librustc_mir/build/matches/test.rs
+++ b/src/librustc_mir/build/matches/test.rs
@@ -30,7 +30,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
Test {
span: match_pair.pattern.span,
kind: TestKind::Switch {
- adt_def: adt_def.clone(),
+ adt_def,
variants: BitSet::new_empty(adt_def.variants.len()),
},
}
diff --git a/src/librustc_mir/build/matches/util.rs b/src/librustc_mir/build/matches/util.rs
index ec8b3c5e24bf2..87481d1d69bc7 100644
--- a/src/librustc_mir/build/matches/util.rs
+++ b/src/librustc_mir/build/matches/util.rs
@@ -109,15 +109,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
},
);
}
- _ => {
- self.cfg.terminate(
- from_block,
- source_info,
- TerminatorKind::Goto {
- target: real_target
- }
- );
- }
+ _ => self.cfg.goto(from_block, source_info, real_target),
}
}
}
diff --git a/src/librustc_mir/build/mod.rs b/src/librustc_mir/build/mod.rs
index 3479ad6749a90..1ecae105694ed 100644
--- a/src/librustc_mir/build/mod.rs
+++ b/src/librustc_mir/build/mod.rs
@@ -606,14 +606,11 @@ where
let fn_end = span.shrink_to_hi();
let source_info = builder.source_info(fn_end);
let return_block = builder.return_block();
- builder.cfg.terminate(block, source_info,
- TerminatorKind::Goto { target: return_block });
- builder.cfg.terminate(return_block, source_info,
- TerminatorKind::Return);
+ builder.cfg.goto(block, source_info, return_block);
+ builder.cfg.terminate(return_block, source_info, TerminatorKind::Return);
// Attribute any unreachable codepaths to the function's closing brace
if let Some(unreachable_block) = builder.cached_unreachable_block {
- builder.cfg.terminate(unreachable_block, source_info,
- TerminatorKind::Unreachable);
+ builder.cfg.terminate(unreachable_block, source_info, TerminatorKind::Unreachable);
}
return_block.unit()
}));
diff --git a/src/librustc_mir/build/scope.rs b/src/librustc_mir/build/scope.rs
index 00a30af806a89..9c5966263dfc0 100644
--- a/src/librustc_mir/build/scope.rs
+++ b/src/librustc_mir/build/scope.rs
@@ -564,14 +564,12 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
let source_info = scope.source_info(span);
block = match scope.cached_exits.entry((target, region_scope)) {
Entry::Occupied(e) => {
- self.cfg.terminate(block, source_info,
- TerminatorKind::Goto { target: *e.get() });
+ self.cfg.goto(block, source_info, *e.get());
return;
}
Entry::Vacant(v) => {
let b = self.cfg.start_new_block();
- self.cfg.terminate(block, source_info,
- TerminatorKind::Goto { target: b });
+ self.cfg.goto(block, source_info, b);
v.insert(b);
b
}
@@ -596,8 +594,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
scope = next_scope;
}
- let source_info = self.scopes.source_info(scope_count, span);
- self.cfg.terminate(block, source_info, TerminatorKind::Goto { target });
+ self.cfg.goto(block, self.scopes.source_info(scope_count, span), target);
}
/// Creates a path that performs all required cleanup for dropping a generator.
@@ -616,14 +613,12 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
while let Some(scope) = scopes.next() {
block = if let Some(b) = scope.cached_generator_drop {
- self.cfg.terminate(block, src_info,
- TerminatorKind::Goto { target: b });
+ self.cfg.goto(block, src_info, b);
return Some(result);
} else {
let b = self.cfg.start_new_block();
scope.cached_generator_drop = Some(b);
- self.cfg.terminate(block, src_info,
- TerminatorKind::Goto { target: b });
+ self.cfg.goto(block, src_info, b);
b
};
@@ -1243,8 +1238,7 @@ fn build_diverge_scope<'tcx>(cfg: &mut CFG<'tcx>,
// block for our StorageDead statements.
let block = cfg.start_new_cleanup_block();
let source_info = SourceInfo { span: DUMMY_SP, scope: source_scope };
- cfg.terminate(block, source_info,
- TerminatorKind::Goto { target: target });
+ cfg.goto(block, source_info, target);
target = block;
target_built_by_us = true;
}