From 5f5b207e2f6b91a5890cda415be98ebe7519d75c Mon Sep 17 00:00:00 2001 From: Scott McMurray Date: Tue, 11 Jun 2024 21:26:41 -0700 Subject: [PATCH] Redo SliceIndex implementations --- library/core/src/slice/index.rs | 122 +++++++++++++----- tests/mir-opt/pre-codegen/slice_index.rs | 26 +++- ...mut_usize.PreCodegen.after.panic-abort.mir | 43 +++++- ...ut_usize.PreCodegen.after.panic-unwind.mir | 43 +++++- ...mut_range.PreCodegen.after.panic-abort.mir | 56 +++++++- ...ut_range.PreCodegen.after.panic-unwind.mir | 56 +++++++- ...ked_range.PreCodegen.after.panic-abort.mir | 40 +++++- ...ed_range.PreCodegen.after.panic-unwind.mir | 40 +++++- 8 files changed, 375 insertions(+), 51 deletions(-) diff --git a/library/core/src/slice/index.rs b/library/core/src/slice/index.rs index 98513340a4741..90f3de9460a0d 100644 --- a/library/core/src/slice/index.rs +++ b/library/core/src/slice/index.rs @@ -2,7 +2,6 @@ use crate::intrinsics::const_eval_select; use crate::ops; -use crate::ptr; use crate::ub_checks::assert_unsafe_precondition; #[stable(feature = "rust1", since = "1.0.0")] @@ -106,6 +105,51 @@ const fn slice_end_index_overflow_fail() -> ! { panic!("attempted to index slice up to maximum usize"); } +// The UbChecks are great for catching bugs in the unsafe methods, but including +// them in safe indexing is unnecessary and hurts inlining and compile-time. +// Both the safe and unsafe public methods share these helpers, +// which use intrinsics directly to get *no* extra checks. + +#[inline(always)] +const unsafe fn get_noubcheck(ptr: *const [T], index: usize) -> *const T { + let ptr = ptr as *const T; + // SAFETY: The caller already checked these preconditions + unsafe { crate::intrinsics::offset(ptr, index) } +} + +#[inline(always)] +const unsafe fn get_mut_noubcheck(ptr: *mut [T], index: usize) -> *mut T { + let ptr = ptr as *mut T; + // SAFETY: The caller already checked these preconditions + unsafe { crate::intrinsics::offset(ptr, index) } +} + +#[inline(always)] +const unsafe fn get_offset_len_noubcheck( + ptr: *const [T], + offset: usize, + len: usize, +) -> *const [T] { + // SAFETY: The caller already checked these preconditions + unsafe { + let ptr = get_noubcheck(ptr, offset); + crate::intrinsics::aggregate_raw_ptr(ptr, len) + } +} + +#[inline(always)] +const unsafe fn get_offset_len_mut_noubcheck( + ptr: *mut [T], + offset: usize, + len: usize, +) -> *mut [T] { + // SAFETY: The caller already checked these preconditions + unsafe { + let ptr = get_mut_noubcheck(ptr, offset); + crate::intrinsics::aggregate_raw_ptr(ptr, len) + } +} + mod private_slice_index { use super::ops; #[stable(feature = "slice_get_slice", since = "1.28.0")] @@ -203,13 +247,17 @@ unsafe impl SliceIndex<[T]> for usize { #[inline] fn get(self, slice: &[T]) -> Option<&T> { // SAFETY: `self` is checked to be in bounds. - if self < slice.len() { unsafe { Some(&*self.get_unchecked(slice)) } } else { None } + if self < slice.len() { unsafe { Some(&*get_noubcheck(slice, self)) } } else { None } } #[inline] fn get_mut(self, slice: &mut [T]) -> Option<&mut T> { - // SAFETY: `self` is checked to be in bounds. - if self < slice.len() { unsafe { Some(&mut *self.get_unchecked_mut(slice)) } } else { None } + if self < slice.len() { + // SAFETY: `self` is checked to be in bounds. + unsafe { Some(&mut *get_mut_noubcheck(slice, self)) } + } else { + None + } } #[inline] @@ -227,7 +275,7 @@ unsafe impl SliceIndex<[T]> for usize { // Use intrinsics::assume instead of hint::assert_unchecked so that we don't check the // precondition of this function twice. crate::intrinsics::assume(self < slice.len()); - slice.as_ptr().add(self) + get_noubcheck(slice, self) } } @@ -239,7 +287,7 @@ unsafe impl SliceIndex<[T]> for usize { (this: usize = self, len: usize = slice.len()) => this < len ); // SAFETY: see comments for `get_unchecked` above. - unsafe { slice.as_mut_ptr().add(self) } + unsafe { get_mut_noubcheck(slice, self) } } #[inline] @@ -265,7 +313,7 @@ unsafe impl SliceIndex<[T]> for ops::IndexRange { fn get(self, slice: &[T]) -> Option<&[T]> { if self.end() <= slice.len() { // SAFETY: `self` is checked to be valid and in bounds above. - unsafe { Some(&*self.get_unchecked(slice)) } + unsafe { Some(&*get_offset_len_noubcheck(slice, self.start(), self.len())) } } else { None } @@ -275,7 +323,7 @@ unsafe impl SliceIndex<[T]> for ops::IndexRange { fn get_mut(self, slice: &mut [T]) -> Option<&mut [T]> { if self.end() <= slice.len() { // SAFETY: `self` is checked to be valid and in bounds above. - unsafe { Some(&mut *self.get_unchecked_mut(slice)) } + unsafe { Some(&mut *get_offset_len_mut_noubcheck(slice, self.start(), self.len())) } } else { None } @@ -292,7 +340,7 @@ unsafe impl SliceIndex<[T]> for ops::IndexRange { // cannot be longer than `isize::MAX`. They also guarantee that // `self` is in bounds of `slice` so `self` cannot overflow an `isize`, // so the call to `add` is safe. - unsafe { ptr::slice_from_raw_parts(slice.as_ptr().add(self.start()), self.len()) } + unsafe { get_offset_len_noubcheck(slice, self.start(), self.len()) } } #[inline] @@ -304,14 +352,14 @@ unsafe impl SliceIndex<[T]> for ops::IndexRange { ); // SAFETY: see comments for `get_unchecked` above. - unsafe { ptr::slice_from_raw_parts_mut(slice.as_mut_ptr().add(self.start()), self.len()) } + unsafe { get_offset_len_mut_noubcheck(slice, self.start(), self.len()) } } #[inline] fn index(self, slice: &[T]) -> &[T] { if self.end() <= slice.len() { // SAFETY: `self` is checked to be valid and in bounds above. - unsafe { &*self.get_unchecked(slice) } + unsafe { &*get_offset_len_noubcheck(slice, self.start(), self.len()) } } else { slice_end_index_len_fail(self.end(), slice.len()) } @@ -321,7 +369,7 @@ unsafe impl SliceIndex<[T]> for ops::IndexRange { fn index_mut(self, slice: &mut [T]) -> &mut [T] { if self.end() <= slice.len() { // SAFETY: `self` is checked to be valid and in bounds above. - unsafe { &mut *self.get_unchecked_mut(slice) } + unsafe { &mut *get_offset_len_mut_noubcheck(slice, self.start(), self.len()) } } else { slice_end_index_len_fail(self.end(), slice.len()) } @@ -338,21 +386,26 @@ unsafe impl SliceIndex<[T]> for ops::Range { #[inline] fn get(self, slice: &[T]) -> Option<&[T]> { - if self.start > self.end || self.end > slice.len() { - None - } else { + // Using checked_sub is a safe way to get `SubUnchecked` in MIR + if let Some(new_len) = usize::checked_sub(self.end, self.start) + && self.end <= slice.len() + { // SAFETY: `self` is checked to be valid and in bounds above. - unsafe { Some(&*self.get_unchecked(slice)) } + unsafe { Some(&*get_offset_len_noubcheck(slice, self.start, new_len)) } + } else { + None } } #[inline] fn get_mut(self, slice: &mut [T]) -> Option<&mut [T]> { - if self.start > self.end || self.end > slice.len() { - None - } else { + if let Some(new_len) = usize::checked_sub(self.end, self.start) + && self.end <= slice.len() + { // SAFETY: `self` is checked to be valid and in bounds above. - unsafe { Some(&mut *self.get_unchecked_mut(slice)) } + unsafe { Some(&mut *get_offset_len_mut_noubcheck(slice, self.start, new_len)) } + } else { + None } } @@ -373,8 +426,10 @@ unsafe impl SliceIndex<[T]> for ops::Range { // `self` is in bounds of `slice` so `self` cannot overflow an `isize`, // so the call to `add` is safe and the length calculation cannot overflow. unsafe { - let new_len = self.end.unchecked_sub(self.start); - ptr::slice_from_raw_parts(slice.as_ptr().add(self.start), new_len) + // Using the intrinsic avoids a superfluous UB check, + // since the one on this method already checked `end >= start`. + let new_len = crate::intrinsics::unchecked_sub(self.end, self.start); + get_offset_len_noubcheck(slice, self.start, new_len) } } @@ -391,31 +446,34 @@ unsafe impl SliceIndex<[T]> for ops::Range { ); // SAFETY: see comments for `get_unchecked` above. unsafe { - let new_len = self.end.unchecked_sub(self.start); - ptr::slice_from_raw_parts_mut(slice.as_mut_ptr().add(self.start), new_len) + let new_len = crate::intrinsics::unchecked_sub(self.end, self.start); + get_offset_len_mut_noubcheck(slice, self.start, new_len) } } #[inline(always)] fn index(self, slice: &[T]) -> &[T] { - if self.start > self.end { - slice_index_order_fail(self.start, self.end); - } else if self.end > slice.len() { + // Using checked_sub is a safe way to get `SubUnchecked` in MIR + let Some(new_len) = usize::checked_sub(self.end, self.start) else { + slice_index_order_fail(self.start, self.end) + }; + if self.end > slice.len() { slice_end_index_len_fail(self.end, slice.len()); } // SAFETY: `self` is checked to be valid and in bounds above. - unsafe { &*self.get_unchecked(slice) } + unsafe { &*get_offset_len_noubcheck(slice, self.start, new_len) } } #[inline] fn index_mut(self, slice: &mut [T]) -> &mut [T] { - if self.start > self.end { - slice_index_order_fail(self.start, self.end); - } else if self.end > slice.len() { + let Some(new_len) = usize::checked_sub(self.end, self.start) else { + slice_index_order_fail(self.start, self.end) + }; + if self.end > slice.len() { slice_end_index_len_fail(self.end, slice.len()); } // SAFETY: `self` is checked to be valid and in bounds above. - unsafe { &mut *self.get_unchecked_mut(slice) } + unsafe { &mut *get_offset_len_mut_noubcheck(slice, self.start, new_len) } } } diff --git a/tests/mir-opt/pre-codegen/slice_index.rs b/tests/mir-opt/pre-codegen/slice_index.rs index 88b99777dd9be..886e57a3380c1 100644 --- a/tests/mir-opt/pre-codegen/slice_index.rs +++ b/tests/mir-opt/pre-codegen/slice_index.rs @@ -1,4 +1,3 @@ -// skip-filecheck //@ compile-flags: -O -C debuginfo=0 -Zmir-opt-level=2 -Z ub-checks=yes // EMIT_MIR_FOR_EACH_PANIC_STRATEGY @@ -9,21 +8,39 @@ use std::ops::Range; // EMIT_MIR slice_index.slice_index_usize.PreCodegen.after.mir pub fn slice_index_usize(slice: &[u32], index: usize) -> u32 { + // CHECK-LABEL: slice_index_usize + // CHECK: [[LEN:_[0-9]+]] = Len((*_1)) + // CHECK: Lt(_2, [[LEN]]) + // CHECK-NOT: precondition_check + // CHECK: _0 = (*_1)[_2]; slice[index] } // EMIT_MIR slice_index.slice_get_mut_usize.PreCodegen.after.mir pub fn slice_get_mut_usize(slice: &mut [u32], index: usize) -> Option<&mut u32> { + // CHECK-LABEL: slice_get_mut_usize + // CHECK: [[LEN:_[0-9]+]] = Len((*_1)) + // CHECK: Lt(_2, move [[LEN]]) + // CHECK-NOT: precondition_check slice.get_mut(index) } // EMIT_MIR slice_index.slice_index_range.PreCodegen.after.mir pub fn slice_index_range(slice: &[u32], index: Range) -> &[u32] { + // CHECK-LABEL: slice_index_range &slice[index] } // EMIT_MIR slice_index.slice_get_unchecked_mut_range.PreCodegen.after.mir pub unsafe fn slice_get_unchecked_mut_range(slice: &mut [u32], index: Range) -> &mut [u32] { + // CHECK-LABEL: slice_get_unchecked_mut_range + // CHECK: [[START:_[0-9]+]] = move (_2.0: usize); + // CHECK: [[END:_[0-9]+]] = move (_2.1: usize); + // CHECK: precondition_check + // CHECK: [[LEN:_[0-9]+]] = SubUnchecked([[END]], [[START]]); + // CHECK: [[PTR:_[0-9]+]] = Offset({{_[0-9]+}}, [[START]]); + // CHECK: [[SLICE:_[0-9]+]] = *mut [u32] from ([[PTR]], [[LEN]]) + // CHECK: _0 = &mut (*[[SLICE]]); slice.get_unchecked_mut(index) } @@ -32,5 +49,12 @@ pub unsafe fn slice_ptr_get_unchecked_range( slice: *const [u32], index: Range, ) -> *const [u32] { + // CHECK-LABEL: slice_ptr_get_unchecked_range + // CHECK: [[START:_[0-9]+]] = move (_2.0: usize); + // CHECK: [[END:_[0-9]+]] = move (_2.1: usize); + // CHECK: precondition_check + // CHECK: [[LEN:_[0-9]+]] = SubUnchecked([[END]], [[START]]); + // CHECK: [[PTR:_[0-9]+]] = Offset({{_[0-9]+}}, [[START]]); + // CHECK: _0 = *const [u32] from ([[PTR]], [[LEN]]) slice.get_unchecked(index) } diff --git a/tests/mir-opt/pre-codegen/slice_index.slice_get_mut_usize.PreCodegen.after.panic-abort.mir b/tests/mir-opt/pre-codegen/slice_index.slice_get_mut_usize.PreCodegen.after.panic-abort.mir index 7e20817cf2301..f2ef2b0cc3c6c 100644 --- a/tests/mir-opt/pre-codegen/slice_index.slice_get_mut_usize.PreCodegen.after.panic-abort.mir +++ b/tests/mir-opt/pre-codegen/slice_index.slice_get_mut_usize.PreCodegen.after.panic-abort.mir @@ -5,13 +5,54 @@ fn slice_get_mut_usize(_1: &mut [u32], _2: usize) -> Option<&mut u32> { debug index => _2; let mut _0: std::option::Option<&mut u32>; scope 1 (inlined core::slice::::get_mut::) { + scope 2 (inlined >::get_mut) { + let mut _3: usize; + let mut _4: bool; + let mut _5: *mut [u32]; + let mut _7: *mut u32; + let mut _8: &mut u32; + scope 3 (inlined core::slice::index::get_mut_noubcheck::) { + let _6: *mut u32; + scope 4 { + } + } + } } bb0: { - _0 = >::get_mut(move _2, move _1) -> [return: bb1, unwind unreachable]; + StorageLive(_7); + StorageLive(_4); + StorageLive(_3); + _3 = Len((*_1)); + _4 = Lt(_2, move _3); + switchInt(move _4) -> [0: bb1, otherwise: bb2]; } bb1: { + StorageDead(_3); + _0 = const Option::<&mut u32>::None; + goto -> bb3; + } + + bb2: { + StorageDead(_3); + StorageLive(_8); + StorageLive(_5); + _5 = &raw mut (*_1); + StorageLive(_6); + _6 = _5 as *mut u32 (PtrToPtr); + _7 = Offset(_6, _2); + StorageDead(_6); + StorageDead(_5); + _8 = &mut (*_7); + _0 = Option::<&mut u32>::Some(move _8); + StorageDead(_8); + goto -> bb3; + } + + bb3: { + StorageDead(_4); + StorageDead(_7); return; } } diff --git a/tests/mir-opt/pre-codegen/slice_index.slice_get_mut_usize.PreCodegen.after.panic-unwind.mir b/tests/mir-opt/pre-codegen/slice_index.slice_get_mut_usize.PreCodegen.after.panic-unwind.mir index 2f65b8c640170..f2ef2b0cc3c6c 100644 --- a/tests/mir-opt/pre-codegen/slice_index.slice_get_mut_usize.PreCodegen.after.panic-unwind.mir +++ b/tests/mir-opt/pre-codegen/slice_index.slice_get_mut_usize.PreCodegen.after.panic-unwind.mir @@ -5,13 +5,54 @@ fn slice_get_mut_usize(_1: &mut [u32], _2: usize) -> Option<&mut u32> { debug index => _2; let mut _0: std::option::Option<&mut u32>; scope 1 (inlined core::slice::::get_mut::) { + scope 2 (inlined >::get_mut) { + let mut _3: usize; + let mut _4: bool; + let mut _5: *mut [u32]; + let mut _7: *mut u32; + let mut _8: &mut u32; + scope 3 (inlined core::slice::index::get_mut_noubcheck::) { + let _6: *mut u32; + scope 4 { + } + } + } } bb0: { - _0 = >::get_mut(move _2, move _1) -> [return: bb1, unwind continue]; + StorageLive(_7); + StorageLive(_4); + StorageLive(_3); + _3 = Len((*_1)); + _4 = Lt(_2, move _3); + switchInt(move _4) -> [0: bb1, otherwise: bb2]; } bb1: { + StorageDead(_3); + _0 = const Option::<&mut u32>::None; + goto -> bb3; + } + + bb2: { + StorageDead(_3); + StorageLive(_8); + StorageLive(_5); + _5 = &raw mut (*_1); + StorageLive(_6); + _6 = _5 as *mut u32 (PtrToPtr); + _7 = Offset(_6, _2); + StorageDead(_6); + StorageDead(_5); + _8 = &mut (*_7); + _0 = Option::<&mut u32>::Some(move _8); + StorageDead(_8); + goto -> bb3; + } + + bb3: { + StorageDead(_4); + StorageDead(_7); return; } } diff --git a/tests/mir-opt/pre-codegen/slice_index.slice_get_unchecked_mut_range.PreCodegen.after.panic-abort.mir b/tests/mir-opt/pre-codegen/slice_index.slice_get_unchecked_mut_range.PreCodegen.after.panic-abort.mir index ef3f4a2172005..5e0398d11147f 100644 --- a/tests/mir-opt/pre-codegen/slice_index.slice_get_unchecked_mut_range.PreCodegen.after.panic-abort.mir +++ b/tests/mir-opt/pre-codegen/slice_index.slice_get_unchecked_mut_range.PreCodegen.after.panic-abort.mir @@ -4,20 +4,62 @@ fn slice_get_unchecked_mut_range(_1: &mut [u32], _2: std::ops::Range) -> debug slice => _1; debug index => _2; let mut _0: &mut [u32]; + let mut _3: usize; + let mut _4: usize; scope 1 (inlined core::slice::::get_unchecked_mut::>) { - let mut _3: *mut [u32]; - let mut _4: *mut [u32]; + let mut _5: *mut [u32]; + let mut _12: *mut [u32]; + scope 2 (inlined as SliceIndex<[u32]>>::get_unchecked_mut) { + let mut _7: usize; + let _8: (); + let _9: usize; + scope 3 { + scope 6 (inlined core::slice::index::get_offset_len_mut_noubcheck::) { + let _11: *mut u32; + scope 7 { + } + scope 8 (inlined core::slice::index::get_mut_noubcheck::) { + let _10: *mut u32; + scope 9 { + } + } + } + } + scope 4 (inlined std::ptr::mut_ptr::::len) { + let mut _6: *const [u32]; + scope 5 (inlined std::ptr::metadata::<[u32]>) { + } + } + } } bb0: { - StorageLive(_3); - _3 = &raw mut (*_1); - _4 = as SliceIndex<[u32]>>::get_unchecked_mut(move _2, move _3) -> [return: bb1, unwind unreachable]; + _3 = move (_2.0: usize); + _4 = move (_2.1: usize); + StorageLive(_5); + _5 = &raw mut (*_1); + StorageLive(_9); + StorageLive(_7); + StorageLive(_6); + _6 = _5 as *const [u32] (PointerCoercion(MutToConstPointer)); + _7 = PtrMetadata(_6); + StorageDead(_6); + _8 = as SliceIndex<[T]>>::get_unchecked_mut::precondition_check(_3, _4, move _7) -> [return: bb1, unwind unreachable]; } bb1: { - StorageDead(_3); - _0 = &mut (*_4); + StorageDead(_7); + _9 = SubUnchecked(_4, _3); + StorageLive(_11); + StorageLive(_10); + _10 = _5 as *mut u32 (PtrToPtr); + _11 = Offset(_10, _3); + StorageDead(_10); + _12 = *mut [u32] from (_11, _9); + StorageDead(_11); + StorageDead(_9); + StorageDead(_5); + _0 = &mut (*_12); return; } } diff --git a/tests/mir-opt/pre-codegen/slice_index.slice_get_unchecked_mut_range.PreCodegen.after.panic-unwind.mir b/tests/mir-opt/pre-codegen/slice_index.slice_get_unchecked_mut_range.PreCodegen.after.panic-unwind.mir index 9e93a43ac725b..5e0398d11147f 100644 --- a/tests/mir-opt/pre-codegen/slice_index.slice_get_unchecked_mut_range.PreCodegen.after.panic-unwind.mir +++ b/tests/mir-opt/pre-codegen/slice_index.slice_get_unchecked_mut_range.PreCodegen.after.panic-unwind.mir @@ -4,20 +4,62 @@ fn slice_get_unchecked_mut_range(_1: &mut [u32], _2: std::ops::Range) -> debug slice => _1; debug index => _2; let mut _0: &mut [u32]; + let mut _3: usize; + let mut _4: usize; scope 1 (inlined core::slice::::get_unchecked_mut::>) { - let mut _3: *mut [u32]; - let mut _4: *mut [u32]; + let mut _5: *mut [u32]; + let mut _12: *mut [u32]; + scope 2 (inlined as SliceIndex<[u32]>>::get_unchecked_mut) { + let mut _7: usize; + let _8: (); + let _9: usize; + scope 3 { + scope 6 (inlined core::slice::index::get_offset_len_mut_noubcheck::) { + let _11: *mut u32; + scope 7 { + } + scope 8 (inlined core::slice::index::get_mut_noubcheck::) { + let _10: *mut u32; + scope 9 { + } + } + } + } + scope 4 (inlined std::ptr::mut_ptr::::len) { + let mut _6: *const [u32]; + scope 5 (inlined std::ptr::metadata::<[u32]>) { + } + } + } } bb0: { - StorageLive(_3); - _3 = &raw mut (*_1); - _4 = as SliceIndex<[u32]>>::get_unchecked_mut(move _2, move _3) -> [return: bb1, unwind continue]; + _3 = move (_2.0: usize); + _4 = move (_2.1: usize); + StorageLive(_5); + _5 = &raw mut (*_1); + StorageLive(_9); + StorageLive(_7); + StorageLive(_6); + _6 = _5 as *const [u32] (PointerCoercion(MutToConstPointer)); + _7 = PtrMetadata(_6); + StorageDead(_6); + _8 = as SliceIndex<[T]>>::get_unchecked_mut::precondition_check(_3, _4, move _7) -> [return: bb1, unwind unreachable]; } bb1: { - StorageDead(_3); - _0 = &mut (*_4); + StorageDead(_7); + _9 = SubUnchecked(_4, _3); + StorageLive(_11); + StorageLive(_10); + _10 = _5 as *mut u32 (PtrToPtr); + _11 = Offset(_10, _3); + StorageDead(_10); + _12 = *mut [u32] from (_11, _9); + StorageDead(_11); + StorageDead(_9); + StorageDead(_5); + _0 = &mut (*_12); return; } } diff --git a/tests/mir-opt/pre-codegen/slice_index.slice_ptr_get_unchecked_range.PreCodegen.after.panic-abort.mir b/tests/mir-opt/pre-codegen/slice_index.slice_ptr_get_unchecked_range.PreCodegen.after.panic-abort.mir index 650069ee6cea3..c61bebe6cc3c0 100644 --- a/tests/mir-opt/pre-codegen/slice_index.slice_ptr_get_unchecked_range.PreCodegen.after.panic-abort.mir +++ b/tests/mir-opt/pre-codegen/slice_index.slice_ptr_get_unchecked_range.PreCodegen.after.panic-abort.mir @@ -4,14 +4,52 @@ fn slice_ptr_get_unchecked_range(_1: *const [u32], _2: std::ops::Range) - debug slice => _1; debug index => _2; let mut _0: *const [u32]; + let mut _3: usize; + let mut _4: usize; scope 1 (inlined std::ptr::const_ptr::::get_unchecked::>) { + scope 2 (inlined as SliceIndex<[u32]>>::get_unchecked) { + let mut _5: usize; + let _6: (); + let _7: usize; + scope 3 { + scope 6 (inlined core::slice::index::get_offset_len_noubcheck::) { + let _9: *const u32; + scope 7 { + } + scope 8 (inlined core::slice::index::get_noubcheck::) { + let _8: *const u32; + scope 9 { + } + } + } + } + scope 4 (inlined std::ptr::const_ptr::::len) { + scope 5 (inlined std::ptr::metadata::<[u32]>) { + } + } + } } bb0: { - _0 = as SliceIndex<[u32]>>::get_unchecked(move _2, move _1) -> [return: bb1, unwind unreachable]; + _3 = move (_2.0: usize); + _4 = move (_2.1: usize); + StorageLive(_7); + StorageLive(_5); + _5 = PtrMetadata(_1); + _6 = as SliceIndex<[T]>>::get_unchecked::precondition_check(_3, _4, move _5) -> [return: bb1, unwind unreachable]; } bb1: { + StorageDead(_5); + _7 = SubUnchecked(_4, _3); + StorageLive(_9); + StorageLive(_8); + _8 = _1 as *const u32 (PtrToPtr); + _9 = Offset(_8, _3); + StorageDead(_8); + _0 = *const [u32] from (_9, _7); + StorageDead(_9); + StorageDead(_7); return; } } diff --git a/tests/mir-opt/pre-codegen/slice_index.slice_ptr_get_unchecked_range.PreCodegen.after.panic-unwind.mir b/tests/mir-opt/pre-codegen/slice_index.slice_ptr_get_unchecked_range.PreCodegen.after.panic-unwind.mir index 74e8158e75430..c61bebe6cc3c0 100644 --- a/tests/mir-opt/pre-codegen/slice_index.slice_ptr_get_unchecked_range.PreCodegen.after.panic-unwind.mir +++ b/tests/mir-opt/pre-codegen/slice_index.slice_ptr_get_unchecked_range.PreCodegen.after.panic-unwind.mir @@ -4,14 +4,52 @@ fn slice_ptr_get_unchecked_range(_1: *const [u32], _2: std::ops::Range) - debug slice => _1; debug index => _2; let mut _0: *const [u32]; + let mut _3: usize; + let mut _4: usize; scope 1 (inlined std::ptr::const_ptr::::get_unchecked::>) { + scope 2 (inlined as SliceIndex<[u32]>>::get_unchecked) { + let mut _5: usize; + let _6: (); + let _7: usize; + scope 3 { + scope 6 (inlined core::slice::index::get_offset_len_noubcheck::) { + let _9: *const u32; + scope 7 { + } + scope 8 (inlined core::slice::index::get_noubcheck::) { + let _8: *const u32; + scope 9 { + } + } + } + } + scope 4 (inlined std::ptr::const_ptr::::len) { + scope 5 (inlined std::ptr::metadata::<[u32]>) { + } + } + } } bb0: { - _0 = as SliceIndex<[u32]>>::get_unchecked(move _2, move _1) -> [return: bb1, unwind continue]; + _3 = move (_2.0: usize); + _4 = move (_2.1: usize); + StorageLive(_7); + StorageLive(_5); + _5 = PtrMetadata(_1); + _6 = as SliceIndex<[T]>>::get_unchecked::precondition_check(_3, _4, move _5) -> [return: bb1, unwind unreachable]; } bb1: { + StorageDead(_5); + _7 = SubUnchecked(_4, _3); + StorageLive(_9); + StorageLive(_8); + _8 = _1 as *const u32 (PtrToPtr); + _9 = Offset(_8, _3); + StorageDead(_8); + _0 = *const [u32] from (_9, _7); + StorageDead(_9); + StorageDead(_7); return; } }