New upstream version 1.47.0+dfsg1

[rustc.git] / src / librustc_mir / transform / no_landing_pads.rs

diff --git a/src/librustc_mir/transform/no_landing_pads.rs b/src/librustc_mir/transform/no_landing_pads.rs
index 55a26f4b37fe2521ae208ecee36cf8e0ec02aa49..1d83733e4cd306bc88868a32f6195286df53327d 100644 (file)
--- a/src/librustc_mir/transform/no_landing_pads.rs
+++ b/src/librustc_mir/transform/no_landing_pads.rs
@@ -1,54 +1,43 @@
-// Copyright 2015 The Rust Project Developers. See the COPYRIGHT
-// file at the top-level directory of this distribution and at
-// http://rust-lang.org/COPYRIGHT.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
 //! This pass removes the unwind branch of all the terminators when the no-landing-pads option is
 //! specified.
 
-use rustc::ty::TyCtxt;
-use rustc::mir::*;
-use rustc::mir::visit::MutVisitor;
-use rustc::mir::transform::{Pass, MirPass, MirSource};
+use crate::transform::{MirPass, MirSource};
+use rustc_middle::mir::visit::MutVisitor;
+use rustc_middle::mir::*;
+use rustc_middle::ty::TyCtxt;
+use rustc_target::spec::PanicStrategy;
 
-pub struct NoLandingPads;
+pub struct NoLandingPads<'tcx> {
+    tcx: TyCtxt<'tcx>,
+}
 
-impl<'tcx> MutVisitor<'tcx> for NoLandingPads {
-    fn visit_terminator(&mut self,
-                        bb: BasicBlock,
-                        terminator: &mut Terminator<'tcx>,
-                        location: Location) {
-        match terminator.kind {
-            TerminatorKind::Goto { .. } |
-            TerminatorKind::Resume |
-            TerminatorKind::Return |
-            TerminatorKind::Unreachable |
-            TerminatorKind::SwitchInt { .. } => {
-                /* nothing to do */
-            },
-            TerminatorKind::Call { cleanup: ref mut unwind, .. } |
-            TerminatorKind::Assert { cleanup: ref mut unwind, .. } |
-            TerminatorKind::DropAndReplace { ref mut unwind, .. } |
-            TerminatorKind::Drop { ref mut unwind, .. } => {
-                unwind.take();
-            },
-        }
-        self.super_terminator(bb, terminator, location);
+impl<'tcx> NoLandingPads<'tcx> {
+    pub fn new(tcx: TyCtxt<'tcx>) -> Self {
+        NoLandingPads { tcx }
     }
 }
 
-impl<'tcx> MirPass<'tcx> for NoLandingPads {
-    fn run_pass<'a>(&mut self, tcx: TyCtxt<'a, 'tcx, 'tcx>,
-                    _: MirSource, mir: &mut Mir<'tcx>) {
-        if tcx.sess.no_landing_pads() {
-            self.visit_mir(mir);
-        }
+impl<'tcx> MirPass<'tcx> for NoLandingPads<'tcx> {
+    fn run_pass(&self, tcx: TyCtxt<'tcx>, _: MirSource<'tcx>, body: &mut Body<'tcx>) {
+        no_landing_pads(tcx, body)
+    }
+}
+
+pub fn no_landing_pads<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
+    if tcx.sess.panic_strategy() == PanicStrategy::Abort {
+        NoLandingPads::new(tcx).visit_body(body);
     }
 }
 
-impl Pass for NoLandingPads {}
+impl<'tcx> MutVisitor<'tcx> for NoLandingPads<'tcx> {
+    fn tcx(&self) -> TyCtxt<'tcx> {
+        self.tcx
+    }
+
+    fn visit_terminator(&mut self, terminator: &mut Terminator<'tcx>, location: Location) {
+        if let Some(unwind) = terminator.kind.unwind_mut() {
+            unwind.take();
+        }
+        self.super_terminator(terminator, location);
+    }
+}