Rollup merge of rust-lang#120158 - jubnzv:120130-mirdf-exports, r=nne…

…thercote

`rustc_mir_dataflow`: Restore removed exports

Added back previously available exports:

* `Forward`/`Backward`: used when implementing `AnalysisDomain`
* `Engine`: used in user's code to solve the dataflow problem
* `SwitchIntEdgeEffects`: used when implementing functions of the `Analysis` trait
* `graphviz`: potentially useful for debugging purposes

Closes rust-lang#120130

compiler/rustc_mir_dataflow/src/lib.rs

@@ -16,15 +16,17 @@ extern crate rustc_middle;
 
 use rustc_middle::ty;
 
+// Please change the public `use` directives cautiously, as they might be used by external tools.
+// See issue #120130.
 pub use self::drop_flag_effects::{
     drop_flag_effects_for_function_entry, drop_flag_effects_for_location,
     move_path_children_matching, on_all_children_bits, on_lookup_result_bits,
 };
 pub use self::framework::{
-    fmt, lattice, visit_results, Analysis, AnalysisDomain, Direction, GenKill, GenKillAnalysis,
-    JoinSemiLattice, MaybeReachable, Results, ResultsCursor, ResultsVisitable, ResultsVisitor,
+    fmt, graphviz, lattice, visit_results, Analysis, AnalysisDomain, Backward, Direction, Engine,
+    Forward, GenKill, GenKillAnalysis, JoinSemiLattice, MaybeReachable, Results, ResultsCursor,
+    ResultsVisitable, ResultsVisitor, SwitchIntEdgeEffects,
 };
-use self::framework::{Backward, SwitchIntEdgeEffects};
 use self::move_paths::MoveData;
 
 pub mod debuginfo;