use the FulfillmentContext and InferCtxt more correctly

src/librustc/mir/mir_map.rs

@@ -12,16 +12,22 @@ use util::nodemap::NodeMap;
 use mir::repr::Mir;
 use mir::transform::MirPass;
 use middle::ty;
+use middle::infer;
 
 pub struct MirMap<'tcx> {
     pub map: NodeMap<Mir<'tcx>>,
 }
 
 impl<'tcx> MirMap<'tcx> {
     pub fn run_passes(&mut self, passes: &mut [Box<MirPass>], tcx: &ty::ctxt<'tcx>) {
-        for (_, ref mut mir) in &mut self.map {
+        if passes.is_empty() { return; }
+
+        for (&id, mir) in &mut self.map {
+            let param_env = ty::ParameterEnvironment::for_item(tcx, id);
+            let infcx = infer::new_infer_ctxt(tcx, &tcx.tables, Some(param_env));
+
             for pass in &mut *passes {
-                pass.run_on_mir(mir, tcx)
+                pass.run_on_mir(mir, &infcx)
             }
         }
     }

src/librustc/mir/transform.rs

@@ -9,8 +9,8 @@
 // except according to those terms.
 
 use mir::repr::Mir;
-use middle::ty::ctxt;
+use middle::infer::InferCtxt;
 
 pub trait MirPass {
-    fn run_on_mir<'tcx>(&mut self, mir: &mut Mir<'tcx>, tcx: &ctxt<'tcx>);
+    fn run_on_mir<'a, 'tcx>(&mut self, mir: &mut Mir<'tcx>, infcx: &InferCtxt<'a, 'tcx>);
 }

src/librustc_mir/mir_map.rs

@@ -149,11 +149,11 @@ impl<'a, 'm, 'tcx> Visitor<'tcx> for InnerDump<'a,'m,'tcx> {
 
         match build_mir(Cx::new(&infcx), implicit_arg_tys, id, span, decl, body) {
             Ok(mut mir) => {
-                clear_dead_blocks::ClearDeadBlocks::new().run_on_mir(&mut mir, self.tcx);
-                type_check::TypeckMir::new(&infcx).run_on_mir(&mut mir, self.tcx);
-                no_landing_pads::NoLandingPads.run_on_mir(&mut mir, self.tcx);
+                clear_dead_blocks::ClearDeadBlocks::new().run_on_mir(&mut mir, &infcx);
+                type_check::TypeckMir::new().run_on_mir(&mut mir, &infcx);
+                no_landing_pads::NoLandingPads.run_on_mir(&mut mir, &infcx);
                 if self.tcx.sess.opts.mir_opt_level > 0 {
-                    simplify_cfg::SimplifyCfg::new().run_on_mir(&mut mir, self.tcx);
+                    simplify_cfg::SimplifyCfg::new().run_on_mir(&mut mir, &infcx);
                 }
                 let meta_item_list = self.attr
                                          .iter()

src/librustc_mir/transform/clear_dead_blocks.rs

@@ -15,7 +15,7 @@
 //! This pass does not renumber or remove the blocks, to have the
 //! MIR better match the source.
 
-use rustc::middle::ty;
+use rustc::middle::infer;
 use rustc::mir::repr::*;
 use rustc::mir::transform::MirPass;
 
@@ -56,7 +56,8 @@ impl ClearDeadBlocks {
 }
 
 impl MirPass for ClearDeadBlocks {
-    fn run_on_mir<'tcx>(&mut self, mir: &mut Mir<'tcx>, _tcx: &ty::ctxt<'tcx>) {
+    fn run_on_mir<'a, 'tcx>(&mut self, mir: &mut Mir<'tcx>, _: &infer::InferCtxt<'a, 'tcx>)
+    {
         self.clear_dead_blocks(mir);
     }
 }

src/librustc_mir/transform/erase_regions.rs

@@ -16,18 +16,13 @@ use rustc::middle::ty;
 use rustc::mir::repr::*;
 use rustc::mir::visit::MutVisitor;
 use rustc::mir::mir_map::MirMap;
-use rustc::mir::transform::MirPass;
 
 pub fn erase_regions<'tcx>(tcx: &ty::ctxt<'tcx>, mir_map: &mut MirMap<'tcx>) {
-    let mut eraser = EraseRegions;
-
     for (_, mir) in &mut mir_map.map {
-        eraser.run_on_mir(mir, tcx);
+        EraseRegionsVisitor::new(tcx).visit_mir(mir);
     }
 }
 
-pub struct EraseRegions;
-
 struct EraseRegionsVisitor<'a, 'tcx: 'a> {
     tcx: &'a ty::ctxt<'tcx>,
 }
@@ -58,12 +53,6 @@ impl<'a, 'tcx> EraseRegionsVisitor<'a, 'tcx> {
     }
 }
 
-impl MirPass for EraseRegions {
-    fn run_on_mir<'tcx>(&mut self, mir: &mut Mir<'tcx>, tcx: &ty::ctxt<'tcx>) {
-        EraseRegionsVisitor::new(tcx).visit_mir(mir);
-    }
-}
-
 impl<'a, 'tcx> MutVisitor<'tcx> for EraseRegionsVisitor<'a, 'tcx> {
     fn visit_mir(&mut self, mir: &mut Mir<'tcx>) {
         self.erase_regions_return_ty(&mut mir.return_ty);

src/librustc_mir/transform/no_landing_pads.rs

@@ -11,7 +11,7 @@
 //! This pass removes the unwind branch of all the terminators when the no-landing-pads option is
 //! specified.
 
-use rustc::middle::ty;
+use rustc::middle::infer;
 use rustc::mir::repr::*;
 use rustc::mir::visit::MutVisitor;
 use rustc::mir::transform::MirPass;
@@ -41,8 +41,9 @@ impl<'tcx> MutVisitor<'tcx> for NoLandingPads {
 }
 
 impl MirPass for NoLandingPads {
-    fn run_on_mir<'tcx>(&mut self, mir: &mut Mir<'tcx>, tcx: &ty::ctxt<'tcx>) {
-        if tcx.sess.no_landing_pads() {
+    fn run_on_mir<'a, 'tcx>(&mut self, mir: &mut Mir<'tcx>,
+                            infcx: &infer::InferCtxt<'a, 'tcx>) {
+        if infcx.tcx.sess.no_landing_pads() {
             self.visit_mir(mir);
         }
     }

src/librustc_mir/transform/simplify_cfg.rs

@@ -9,6 +9,7 @@
 // except according to those terms.
 
 use rustc::middle::const_eval::ConstVal;
+use rustc::middle::infer;
 use rustc::mir::repr::*;
 use transform::util;
 use rustc::mir::transform::MirPass;
@@ -119,7 +120,7 @@ impl SimplifyCfg {
 }
 
 impl MirPass for SimplifyCfg {
-    fn run_on_mir<'tcx>(&mut self, mir: &mut Mir<'tcx>, _: &::rustc::middle::ty::ctxt<'tcx>) {
+    fn run_on_mir<'a, 'tcx>(&mut self, mir: &mut Mir<'tcx>, _: &infer::InferCtxt<'a, 'tcx>) {
         let mut changed = true;
         while changed {
             changed = self.simplify_branches(mir);