diff options
5 files changed, 26 insertions, 4 deletions
diff --git a/compiler/rustc_mir_transform/src/const_prop.rs b/compiler/rustc_mir_transform/src/const_prop.rs index 7f995c69a48..a5d18fff89b 100644 --- a/compiler/rustc_mir_transform/src/const_prop.rs +++ b/compiler/rustc_mir_transform/src/const_prop.rs @@ -806,6 +806,24 @@ impl<'tcx> MutVisitor<'tcx> for ConstPropagator<'_, 'tcx> { } } + fn process_projection_elem( + &mut self, + elem: PlaceElem<'tcx>, + _: Location, + ) -> Option<PlaceElem<'tcx>> { + if let PlaceElem::Index(local) = elem + && let Some(value) = self.get_const(local.into()) + && self.should_const_prop(&value) + && let interpret::Operand::Immediate(interpret::Immediate::Scalar(scalar)) = *value + && let Ok(offset) = scalar.to_target_usize(&self.tcx) + && let Some(min_length) = offset.checked_add(1) + { + Some(PlaceElem::ConstantIndex { offset, min_length, from_end: false }) + } else { + None + } + } + fn visit_assign( &mut self, place: &mut Place<'tcx>, diff --git a/tests/mir-opt/const_prop/bad_op_unsafe_oob_for_slices.main.ConstProp.32bit.diff b/tests/mir-opt/const_prop/bad_op_unsafe_oob_for_slices.main.ConstProp.32bit.diff index f63ee705d92..d72675c2d11 100644 --- a/tests/mir-opt/const_prop/bad_op_unsafe_oob_for_slices.main.ConstProp.32bit.diff +++ b/tests/mir-opt/const_prop/bad_op_unsafe_oob_for_slices.main.ConstProp.32bit.diff @@ -45,7 +45,8 @@ } bb1: { - _5 = (*_1)[_6]; // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:+3:18: +3:25 +- _5 = (*_1)[_6]; // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:+3:18: +3:25 ++ _5 = (*_1)[3 of 4]; // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:+3:18: +3:25 StorageDead(_6); // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:+3:25: +3:26 _0 = const (); // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:+2:5: +4:6 StorageDead(_5); // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:+4:5: +4:6 diff --git a/tests/mir-opt/const_prop/bad_op_unsafe_oob_for_slices.main.ConstProp.64bit.diff b/tests/mir-opt/const_prop/bad_op_unsafe_oob_for_slices.main.ConstProp.64bit.diff index f63ee705d92..d72675c2d11 100644 --- a/tests/mir-opt/const_prop/bad_op_unsafe_oob_for_slices.main.ConstProp.64bit.diff +++ b/tests/mir-opt/const_prop/bad_op_unsafe_oob_for_slices.main.ConstProp.64bit.diff @@ -45,7 +45,8 @@ } bb1: { - _5 = (*_1)[_6]; // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:+3:18: +3:25 +- _5 = (*_1)[_6]; // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:+3:18: +3:25 ++ _5 = (*_1)[3 of 4]; // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:+3:18: +3:25 StorageDead(_6); // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:+3:25: +3:26 _0 = const (); // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:+2:5: +4:6 StorageDead(_5); // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:+4:5: +4:6 diff --git a/tests/mir-opt/const_prop/large_array_index.main.ConstProp.32bit.diff b/tests/mir-opt/const_prop/large_array_index.main.ConstProp.32bit.diff index 36336d967a9..33bbad2f422 100644 --- a/tests/mir-opt/const_prop/large_array_index.main.ConstProp.32bit.diff +++ b/tests/mir-opt/const_prop/large_array_index.main.ConstProp.32bit.diff @@ -27,7 +27,8 @@ } bb1: { - _1 = _2[_3]; // scope 0 at $DIR/large_array_index.rs:+2:17: +2:32 +- _1 = _2[_3]; // scope 0 at $DIR/large_array_index.rs:+2:17: +2:32 ++ _1 = _2[2 of 3]; // scope 0 at $DIR/large_array_index.rs:+2:17: +2:32 StorageDead(_3); // scope 0 at $DIR/large_array_index.rs:+2:32: +2:33 StorageDead(_2); // scope 0 at $DIR/large_array_index.rs:+2:32: +2:33 _0 = const (); // scope 0 at $DIR/large_array_index.rs:+0:11: +3:2 diff --git a/tests/mir-opt/const_prop/large_array_index.main.ConstProp.64bit.diff b/tests/mir-opt/const_prop/large_array_index.main.ConstProp.64bit.diff index 36336d967a9..33bbad2f422 100644 --- a/tests/mir-opt/const_prop/large_array_index.main.ConstProp.64bit.diff +++ b/tests/mir-opt/const_prop/large_array_index.main.ConstProp.64bit.diff @@ -27,7 +27,8 @@ } bb1: { - _1 = _2[_3]; // scope 0 at $DIR/large_array_index.rs:+2:17: +2:32 +- _1 = _2[_3]; // scope 0 at $DIR/large_array_index.rs:+2:17: +2:32 ++ _1 = _2[2 of 3]; // scope 0 at $DIR/large_array_index.rs:+2:17: +2:32 StorageDead(_3); // scope 0 at $DIR/large_array_index.rs:+2:32: +2:33 StorageDead(_2); // scope 0 at $DIR/large_array_index.rs:+2:32: +2:33 _0 = const (); // scope 0 at $DIR/large_array_index.rs:+0:11: +3:2 |