Remove obsolete CallGuards MIR pass

Author: Mark-Simulacrum

src/librustc_driver/driver.rs

@@ -1050,7 +1050,6 @@ pub fn phase_4_translate_to_llvm<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
         // From here on out, regions are gone.
         passes.push_pass(box mir::transform::erase_regions::EraseRegions);
 
-        passes.push_pass(box mir::transform::add_call_guards::AddCallGuards);
         passes.push_pass(box borrowck::ElaborateDrops);
         passes.push_pass(box mir::transform::no_landing_pads::NoLandingPads);
         passes.push_pass(box mir::transform::simplify::SimplifyCfg::new("elaborate-drops"));
@@ -1062,7 +1061,6 @@ pub fn phase_4_translate_to_llvm<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
         passes.push_pass(box mir::transform::copy_prop::CopyPropagation);
 
         passes.push_pass(box mir::transform::simplify::SimplifyLocals);
-        passes.push_pass(box mir::transform::add_call_guards::AddCallGuards);
         passes.push_pass(box mir::transform::dump_mir::Marker("PreTrans"));
 
         passes.run_passes(tcx);

src/librustc_mir/shim.rs

@@ -30,7 +30,7 @@ use std::fmt;
 use std::iter;
 use std::mem;
 
-use transform::{add_call_guards, no_landing_pads, simplify};
+use transform::{no_landing_pads, simplify};
 use util::elaborate_drops::{self, DropElaborator, DropStyle, DropFlagMode};
 use util::patch::MirPatch;
 
@@ -115,7 +115,6 @@ fn make_shim<'a, 'tcx>(tcx: ty::TyCtxt<'a, 'tcx, 'tcx>,
         debug!("make_shim({:?}) = untransformed {:?}", instance, result);
         no_landing_pads::no_landing_pads(tcx, &mut result);
         simplify::simplify_cfg(&mut result);
-        add_call_guards::add_call_guards(&mut result);
     debug!("make_shim({:?}) = {:?}", instance, result);
 
     let result = tcx.alloc_mir(result);

src/librustc_mir/transform/add_call_guards.rs

@@ -13,7 +13,6 @@ pub mod simplify;
 pub mod erase_regions;
 pub mod no_landing_pads;
 pub mod type_check;
-pub mod add_call_guards;
 pub mod promote_consts;
 pub mod qualify_consts;
 pub mod dump_mir;