Move dominators from Body to BasicBlocks

compiler/rustc_middle/src/mir/basic_blocks.rs

@@ -5,6 +5,7 @@ use crate::mir::traversal::PostorderCache;
 use crate::mir::{BasicBlock, BasicBlockData, Successors, START_BLOCK};
 
 use rustc_data_structures::graph;
+use rustc_data_structures::graph::dominators::{dominators, Dominators};
 use rustc_index::vec::IndexVec;
 
 #[derive(Clone, TyEncodable, TyDecodable, Debug, HashStable, TypeFoldable, TypeVisitable)]
@@ -34,6 +35,11 @@ impl<'tcx> BasicBlocks<'tcx> {
         self.is_cyclic.is_cyclic(self)
     }
 
+    #[inline]
+    pub fn dominators(&self) -> Dominators<BasicBlock> {
+        dominators(&self)
+    }
+
     /// Returns predecessors for each basic block.
     #[inline]
     pub fn predecessors(&self) -> &Predecessors {

compiler/rustc_middle/src/mir/mod.rs

@@ -26,7 +26,7 @@ use rustc_target::abi::{Size, VariantIdx};
 use polonius_engine::Atom;
 pub use rustc_ast::Mutability;
 use rustc_data_structures::fx::FxHashSet;
-use rustc_data_structures::graph::dominators::{dominators, Dominators};
+use rustc_data_structures::graph::dominators::Dominators;
 use rustc_index::bit_set::BitMatrix;
 use rustc_index::vec::{Idx, IndexVec};
 use rustc_serialize::{Decodable, Encodable};
@@ -447,11 +447,6 @@ impl<'tcx> Body<'tcx> {
             .unwrap_or_else(|| Either::Right(block_data.terminator()))
     }
 
-    #[inline]
-    pub fn dominators(&self) -> Dominators<BasicBlock> {
-        dominators(&self.basic_blocks)
-    }
-
     #[inline]
     pub fn yield_ty(&self) -> Option<Ty<'tcx>> {
         self.generator.as_ref().and_then(|generator| generator.yield_ty)