diff options
4 files changed, 294 insertions, 9 deletions
diff --git a/compiler/rustc_mir_transform/src/gvn.rs b/compiler/rustc_mir_transform/src/gvn.rs index d2ffd26f0a0..1a2120ecd71 100644 --- a/compiler/rustc_mir_transform/src/gvn.rs +++ b/compiler/rustc_mir_transform/src/gvn.rs @@ -1367,16 +1367,17 @@ impl<'body, 'tcx> VnState<'body, 'tcx> { fn simplify_cast( &mut self, - kind: &mut CastKind, - operand: &mut Operand<'tcx>, + initial_kind: &mut CastKind, + initial_operand: &mut Operand<'tcx>, to: Ty<'tcx>, location: Location, ) -> Option<VnIndex> { use CastKind::*; use rustc_middle::ty::adjustment::PointerCoercion::*; - let mut from = operand.ty(self.local_decls, self.tcx); - let mut value = self.simplify_operand(operand, location)?; + let mut from = initial_operand.ty(self.local_decls, self.tcx); + let mut kind = *initial_kind; + let mut value = self.simplify_operand(initial_operand, location)?; if from == to { return Some(value); } @@ -1400,7 +1401,7 @@ impl<'body, 'tcx> VnState<'body, 'tcx> { && to.is_unsafe_ptr() && self.pointers_have_same_metadata(from, to) { - *kind = PtrToPtr; + kind = PtrToPtr; was_updated_this_iteration = true; } @@ -1443,7 +1444,7 @@ impl<'body, 'tcx> VnState<'body, 'tcx> { to: inner_to, } = *self.get(value) { - let new_kind = match (inner_kind, *kind) { + let new_kind = match (inner_kind, kind) { // Even if there's a narrowing cast in here that's fine, because // things like `*mut [i32] -> *mut i32 -> *const i32` and // `*mut [i32] -> *const [i32] -> *const i32` can skip the middle in MIR. @@ -1471,7 +1472,7 @@ impl<'body, 'tcx> VnState<'body, 'tcx> { _ => None, }; if let Some(new_kind) = new_kind { - *kind = new_kind; + kind = new_kind; from = inner_from; value = inner_value; was_updated_this_iteration = true; @@ -1489,10 +1490,11 @@ impl<'body, 'tcx> VnState<'body, 'tcx> { } if was_ever_updated && let Some(op) = self.try_as_operand(value, location) { - *operand = op; + *initial_operand = op; + *initial_kind = kind; } - Some(self.insert(Value::Cast { kind: *kind, value, from, to })) + Some(self.insert(Value::Cast { kind, value, from, to })) } fn simplify_len(&mut self, place: &mut Place<'tcx>, location: Location) -> Option<VnIndex> { diff --git a/tests/mir-opt/dont_reset_cast_kind_without_updating_operand.rs b/tests/mir-opt/dont_reset_cast_kind_without_updating_operand.rs new file mode 100644 index 00000000000..635ad825a12 --- /dev/null +++ b/tests/mir-opt/dont_reset_cast_kind_without_updating_operand.rs @@ -0,0 +1,15 @@ +// skip-filecheck +//@ compile-flags: -Zmir-enable-passes=+Inline,+GVN --crate-type lib +// EMIT_MIR_FOR_EACH_PANIC_STRATEGY +// EMIT_MIR dont_reset_cast_kind_without_updating_operand.test.GVN.diff + +fn test() { + let vp_ctx: &Box<()> = &Box::new(()); + let slf: *const () = &raw const **vp_ctx; + let bytes = std::ptr::slice_from_raw_parts(slf, 1); + let _x = foo(bytes); +} + +fn foo(bytes: *const [()]) -> *mut () { + bytes as *mut () +} diff --git a/tests/mir-opt/dont_reset_cast_kind_without_updating_operand.test.GVN.panic-abort.diff b/tests/mir-opt/dont_reset_cast_kind_without_updating_operand.test.GVN.panic-abort.diff new file mode 100644 index 00000000000..37dd14e6c89 --- /dev/null +++ b/tests/mir-opt/dont_reset_cast_kind_without_updating_operand.test.GVN.panic-abort.diff @@ -0,0 +1,180 @@ +- // MIR for `test` before GVN ++ // MIR for `test` after GVN + + fn test() -> () { + let mut _0: (); + let _1: &std::boxed::Box<()>; + let _2: &std::boxed::Box<()>; + let _3: std::boxed::Box<()>; + let mut _6: *const (); + let mut _8: *const [()]; + let mut _9: std::boxed::Box<()>; + let mut _10: *const (); + let mut _23: usize; + scope 1 { + debug vp_ctx => _1; + let _4: *const (); + scope 2 { + debug slf => _10; + let _5: *const [()]; + scope 3 { + debug bytes => _5; + let _7: *mut (); + scope 4 { + debug _x => _7; + } + scope 18 (inlined foo) { + } + } + scope 16 (inlined slice_from_raw_parts::<()>) { + scope 17 (inlined std::ptr::from_raw_parts::<[()], ()>) { + } + } + } + } + scope 5 (inlined Box::<()>::new) { + let mut _11: usize; + let mut _12: usize; + let mut _13: *mut u8; + scope 6 (inlined alloc::alloc::exchange_malloc) { + let _14: std::alloc::Layout; + let mut _15: std::result::Result<std::ptr::NonNull<[u8]>, std::alloc::AllocError>; + let mut _16: isize; + let mut _18: !; + scope 7 { + let _17: std::ptr::NonNull<[u8]>; + scope 8 { + scope 11 (inlined NonNull::<[u8]>::as_mut_ptr) { + scope 12 (inlined NonNull::<[u8]>::as_non_null_ptr) { + scope 13 (inlined NonNull::<[u8]>::cast::<u8>) { + let mut _22: *mut [u8]; + scope 14 (inlined NonNull::<[u8]>::as_ptr) { + } + } + } + scope 15 (inlined NonNull::<u8>::as_ptr) { + } + } + } + scope 10 (inlined <std::alloc::Global as Allocator>::allocate) { + } + } + scope 9 (inlined Layout::from_size_align_unchecked) { + let mut _19: bool; + let _20: (); + let mut _21: std::ptr::Alignment; + } + } + } + + bb0: { + StorageLive(_1); +- StorageLive(_2); ++ nop; + StorageLive(_3); + StorageLive(_11); + StorageLive(_12); + StorageLive(_13); +- _11 = SizeOf(()); +- _12 = AlignOf(()); ++ _11 = const 0_usize; ++ _12 = const 1_usize; + StorageLive(_14); + StorageLive(_16); + StorageLive(_17); + StorageLive(_19); + _19 = const false; +- switchInt(move _19) -> [0: bb6, otherwise: bb5]; ++ switchInt(const false) -> [0: bb6, otherwise: bb5]; + } + + bb1: { + StorageDead(_3); + StorageDead(_1); + return; + } + + bb2: { + unreachable; + } + + bb3: { +- _18 = handle_alloc_error(move _14) -> unwind unreachable; ++ _18 = handle_alloc_error(const Layout {{ size: 0_usize, align: std::ptr::Alignment(std::ptr::alignment::AlignmentEnum::_Align1Shl0) }}) -> unwind unreachable; + } + + bb4: { + _17 = copy ((_15 as Ok).0: std::ptr::NonNull<[u8]>); + StorageLive(_22); + _22 = copy _17 as *mut [u8] (Transmute); + _13 = copy _22 as *mut u8 (PtrToPtr); + StorageDead(_22); + StorageDead(_15); + StorageDead(_17); + StorageDead(_16); + StorageDead(_14); + _3 = ShallowInitBox(move _13, ()); + StorageDead(_13); + StorageDead(_12); + StorageDead(_11); + _2 = &_3; + _1 = copy _2; +- StorageDead(_2); ++ nop; + StorageLive(_4); +- _9 = deref_copy _3; ++ _9 = copy _3; + _10 = copy ((_9.0: std::ptr::Unique<()>).0: std::ptr::NonNull<()>) as *const () (Transmute); + _4 = copy _10; +- StorageLive(_5); ++ nop; + StorageLive(_6); +- _6 = copy _4; ++ _6 = copy _10; + StorageLive(_23); + _23 = const 1_usize; +- _5 = *const [()] from (copy _6, copy _23); ++ _5 = *const [()] from (copy _10, const 1_usize); + StorageDead(_23); + StorageDead(_6); + StorageLive(_7); + StorageLive(_8); + _8 = copy _5; +- _7 = copy _8 as *mut () (PtrToPtr); ++ _7 = copy _5 as *mut () (PtrToPtr); + StorageDead(_8); + StorageDead(_7); +- StorageDead(_5); ++ nop; + StorageDead(_4); + drop(_3) -> [return: bb1, unwind unreachable]; + } + + bb5: { +- _20 = Layout::from_size_align_unchecked::precondition_check(copy _11, copy _12) -> [return: bb6, unwind unreachable]; ++ _20 = Layout::from_size_align_unchecked::precondition_check(const 0_usize, const 1_usize) -> [return: bb6, unwind unreachable]; + } + + bb6: { + StorageDead(_19); + StorageLive(_21); +- _21 = copy _12 as std::ptr::Alignment (Transmute); +- _14 = Layout { size: copy _11, align: move _21 }; ++ _21 = const std::ptr::Alignment(std::ptr::alignment::AlignmentEnum::_Align1Shl0); ++ _14 = const Layout {{ size: 0_usize, align: std::ptr::Alignment(std::ptr::alignment::AlignmentEnum::_Align1Shl0) }}; + StorageDead(_21); + StorageLive(_15); +- _15 = std::alloc::Global::alloc_impl(const alloc::alloc::exchange_malloc::promoted[0], copy _14, const false) -> [return: bb7, unwind unreachable]; ++ _15 = std::alloc::Global::alloc_impl(const alloc::alloc::exchange_malloc::promoted[0], const Layout {{ size: 0_usize, align: std::ptr::Alignment(std::ptr::alignment::AlignmentEnum::_Align1Shl0) }}, const false) -> [return: bb7, unwind unreachable]; + } + + bb7: { + _16 = discriminant(_15); + switchInt(move _16) -> [0: bb4, 1: bb3, otherwise: bb2]; + } ++ } ++ ++ ALLOC0 (size: 8, align: 4) { ++ 01 00 00 00 00 00 00 00 │ ........ + } + diff --git a/tests/mir-opt/dont_reset_cast_kind_without_updating_operand.test.GVN.panic-unwind.diff b/tests/mir-opt/dont_reset_cast_kind_without_updating_operand.test.GVN.panic-unwind.diff new file mode 100644 index 00000000000..6bac6805943 --- /dev/null +++ b/tests/mir-opt/dont_reset_cast_kind_without_updating_operand.test.GVN.panic-unwind.diff @@ -0,0 +1,88 @@ +- // MIR for `test` before GVN ++ // MIR for `test` after GVN + + fn test() -> () { + let mut _0: (); + let _1: &std::boxed::Box<()>; + let _2: &std::boxed::Box<()>; + let _3: std::boxed::Box<()>; + let mut _6: *const (); + let mut _8: *const [()]; + let mut _9: std::boxed::Box<()>; + let mut _10: *const (); + let mut _11: usize; + scope 1 { + debug vp_ctx => _1; + let _4: *const (); + scope 2 { + debug slf => _10; + let _5: *const [()]; + scope 3 { + debug bytes => _5; + let _7: *mut (); + scope 4 { + debug _x => _7; + } + scope 7 (inlined foo) { + } + } + scope 5 (inlined slice_from_raw_parts::<()>) { + scope 6 (inlined std::ptr::from_raw_parts::<[()], ()>) { + } + } + } + } + + bb0: { + StorageLive(_1); +- StorageLive(_2); ++ nop; + StorageLive(_3); + _3 = Box::<()>::new(const ()) -> [return: bb1, unwind continue]; + } + + bb1: { + _2 = &_3; + _1 = copy _2; +- StorageDead(_2); ++ nop; + StorageLive(_4); +- _9 = deref_copy _3; ++ _9 = copy _3; + _10 = copy ((_9.0: std::ptr::Unique<()>).0: std::ptr::NonNull<()>) as *const () (Transmute); + _4 = copy _10; +- StorageLive(_5); ++ nop; + StorageLive(_6); +- _6 = copy _4; ++ _6 = copy _10; + StorageLive(_11); + _11 = const 1_usize; +- _5 = *const [()] from (copy _6, copy _11); ++ _5 = *const [()] from (copy _10, const 1_usize); + StorageDead(_11); + StorageDead(_6); + StorageLive(_7); + StorageLive(_8); + _8 = copy _5; +- _7 = copy _8 as *mut () (PtrToPtr); ++ _7 = copy _5 as *mut () (PtrToPtr); + StorageDead(_8); + StorageDead(_7); +- StorageDead(_5); ++ nop; + StorageDead(_4); + drop(_3) -> [return: bb2, unwind: bb3]; + } + + bb2: { + StorageDead(_3); + StorageDead(_1); + return; + } + + bb3 (cleanup): { + resume; + } + } + |