Move MirPass to rustc_mir_transform.

Because that's now the only crate that uses it.
Moving stuff out of `rustc_middle` is always welcome.
I chose to use `impl crate::MirPass`/`impl crate::MirLint` (with
explicit `crate::`) everywhere because that's the only mention of
`MirPass`/`MirLint` used in all of these files. (Prior to this change,
`MirPass` was mostly imported via `use rustc_middle::mir::*` items.)

Author: nnethercote

compiler/rustc_middle/src/mir/mod.rs

@@ -3,8 +3,6 @@
 //! [rustc dev guide]: https://rustc-dev-guide.rust-lang.org/mir/index.html
 
 use std::borrow::Cow;
-use std::cell::RefCell;
-use std::collections::hash_map::Entry;
 use std::fmt::{self,Debug,Formatter};
 use std::ops::{Index,IndexMut};
 use std::{iter, mem};
@@ -26,7 +24,6 @@ use rustc_index::bit_set::BitSet;
 use rustc_index::{Idx,IndexSlice,IndexVec};
 use rustc_macros::{HashStable,TyDecodable,TyEncodable,TypeFoldable,TypeVisitable};
 use rustc_serialize::{Decodable,Encodable};
-use rustc_session::Session;
 use rustc_span::source_map::Spanned;
 use rustc_span::symbol::Symbol;
 use rustc_span::{Span,DUMMY_SP};
@@ -106,65 +103,6 @@ impl<'tcx> HasLocalDecls<'tcx> for Body<'tcx> {
 }
 }
 
-thread_local!{
-staticPASS_NAMES:RefCell<FxHashMap<&'staticstr,&'staticstr>> = {
-RefCell::new(FxHashMap::default())
-};
-}
-
-/// Converts a MIR pass name into a snake case form to match the profiling naming style.
-fnto_profiler_name(type_name:&'staticstr) -> &'staticstr{
-PASS_NAMES.with(|names| match names.borrow_mut().entry(type_name){
-Entry::Occupied(e) => *e.get(),
-Entry::Vacant(e) => {
-let snake_case:String = type_name
-.chars()
-.flat_map(|c| {
-if c.is_ascii_uppercase(){
-vec!['_', c.to_ascii_lowercase()]
-}elseif c == '-'{
-vec!['_']
-}else{
-vec![c]
-}
-})
-.collect();
-let result = &*String::leak(format!("mir_pass{}", snake_case));
- e.insert(result);
- result
-}
-})
-}
-
-/// A streamlined trait that you can implement to create a pass; the
-/// pass will be named after the type, and it will consist of a main
-/// loop that goes over each available MIR and applies `run_pass`.
-pubtraitMirPass<'tcx>{
-fnname(&self) -> &'staticstr{
-// FIXME Simplify the implementation once more `str` methods get const-stable.
-// See copypaste in `MirLint`
-const{
-let name = std::any::type_name::<Self>();
-crate::util::common::c_name(name)
-}
-}
-
-fnprofiler_name(&self) -> &'staticstr{
-to_profiler_name(self.name())
-}
-
-/// Returns `true` if this pass is enabled with the current combination of compiler flags.
-fnis_enabled(&self,_sess:&Session) -> bool{
-true
-}
-
-fnrun_pass(&self,tcx:TyCtxt<'tcx>,body:&mutBody<'tcx>);
-
-fnis_mir_dump_enabled(&self) -> bool{
-true
-}
-}
-
 implMirPhase{
 /// Gets the index of the current MirPhase within the set of all `MirPhase`s.
 ///

compiler/rustc_middle/src/util/common.rs

@@ -20,19 +20,3 @@ pub fn to_readable_str(mut val: usize) -> String {
 
  groups.join("_")
 }
-
-// const wrapper for `if let Some((_, tail)) = name.rsplit_once(':') { tail } else { name }`
-pubconstfnc_name(name:&'staticstr) -> &'staticstr{
-// FIXME Simplify the implementation once more `str` methods get const-stable.
-// and inline into call site
-let bytes = name.as_bytes();
-letmut i = bytes.len();
-while i > 0 && bytes[i - 1] != b':'{
- i = i - 1;
-}
-let(_, bytes) = bytes.split_at(i);
-match std::str::from_utf8(bytes){
-Ok(name) => name,
-Err(_) => name,
-}
-}

compiler/rustc_mir_transform/src/abort_unwinding_calls.rs

@@ -22,7 +22,7 @@ use rustc_target::spec::PanicStrategy;
 #[derive(PartialEq)]
 pubstructAbortUnwindingCalls;
 
-impl<'tcx>MirPass<'tcx>forAbortUnwindingCalls{
+impl<'tcx>crate::MirPass<'tcx>forAbortUnwindingCalls{
 fnrun_pass(&self,tcx:TyCtxt<'tcx>,body:&mutBody<'tcx>){
 let def_id = body.source.def_id();
 let kind = tcx.def_kind(def_id);

compiler/rustc_mir_transform/src/add_call_guards.rs

@@ -30,7 +30,7 @@ pub use self::AddCallGuards::*;
  *
  */
 
-impl<'tcx>MirPass<'tcx>forAddCallGuards{
+impl<'tcx>crate::MirPass<'tcx>forAddCallGuards{
 fnrun_pass(&self,_tcx:TyCtxt<'tcx>,body:&mutBody<'tcx>){
 self.add_call_guards(body);
 }

compiler/rustc_mir_transform/src/add_moves_for_packed_drops.rs

@@ -37,7 +37,7 @@ use crate::util;
 /// blowup.
 pubstructAddMovesForPackedDrops;
 
-impl<'tcx>MirPass<'tcx>forAddMovesForPackedDrops{
+impl<'tcx>crate::MirPass<'tcx>forAddMovesForPackedDrops{
 fnrun_pass(&self,tcx:TyCtxt<'tcx>,body:&mutBody<'tcx>){
 debug!("add_moves_for_packed_drops({:?} @ {:?})", body.source, body.span);
 add_moves_for_packed_drops(tcx, body);

compiler/rustc_mir_transform/src/add_retag.rs

@@ -48,7 +48,7 @@ fn may_contain_reference<'tcx>(ty: Ty<'tcx>, depth: u32, tcx: TyCtxt<'tcx>) -> b
 }
 }
 
-impl<'tcx>MirPass<'tcx>forAddRetag{
+impl<'tcx>crate::MirPass<'tcx>forAddRetag{
 fnis_enabled(&self,sess:&rustc_session::Session) -> bool{
  sess.opts.unstable_opts.mir_emit_retag
 }

compiler/rustc_mir_transform/src/add_subtyping_projections.rs

@@ -62,7 +62,7 @@ pub fn subtype_finder<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
  checker.patcher.apply(body);
 }
 
-impl<'tcx>MirPass<'tcx>forSubtyper{
+impl<'tcx>crate::MirPass<'tcx>forSubtyper{
 fnrun_pass(&self,tcx:TyCtxt<'tcx>,body:&mutBody<'tcx>){
 subtype_finder(tcx, body);
 }

compiler/rustc_mir_transform/src/check_alignment.rs

@@ -9,7 +9,7 @@ use tracing::{debug, trace};
 
 pubstructCheckAlignment;
 
-impl<'tcx>MirPass<'tcx>forCheckAlignment{
+impl<'tcx>crate::MirPass<'tcx>forCheckAlignment{
 fnis_enabled(&self,sess:&Session) -> bool{
 // FIXME(#112480) MSVC and rustc disagree on minimum stack alignment on x86 Windows
 if sess.target.llvm_target == "i686-pc-windows-msvc"{

compiler/rustc_mir_transform/src/check_const_item_mutation.rs

@@ -6,11 +6,11 @@ use rustc_session::lint::builtin::CONST_ITEM_MUTATION;
 use rustc_span::def_id::DefId;
 use rustc_span::Span;
 
-usecrate::{errors,MirLint};
+usecrate::errors;
 
 pubstructCheckConstItemMutation;
 
-impl<'tcx>MirLint<'tcx>forCheckConstItemMutation{
+impl<'tcx>crate::MirLint<'tcx>forCheckConstItemMutation{
 fnrun_lint(&self,tcx:TyCtxt<'tcx>,body:&Body<'tcx>){
 letmut checker = ConstMutationChecker{ body, tcx,target_local:None};
  checker.visit_body(body);

compiler/rustc_mir_transform/src/check_packed_ref.rs

@@ -3,11 +3,11 @@ use rustc_middle::mir::*;
 use rustc_middle::span_bug;
 use rustc_middle::ty::{self,TyCtxt};
 
-usecrate::{errors, util,MirLint};
+usecrate::{errors, util};
 
 pubstructCheckPackedRef;
 
-impl<'tcx>MirLint<'tcx>forCheckPackedRef{
+impl<'tcx>crate::MirLint<'tcx>forCheckPackedRef{
 fnrun_lint(&self,tcx:TyCtxt<'tcx>,body:&Body<'tcx>){
 let param_env = tcx.param_env(body.source.def_id());
 let source_info = SourceInfo::outermost(body.span);