Make MIR inlining costs in build-std independent of config.toml

This commit is contained in:
Scott McMurray 2024-06-23 00:34:40 -07:00
parent 49d353bb9f
commit dd545e148c
6 changed files with 818 additions and 70 deletions

View File

@ -60,7 +60,15 @@ impl<'tcx> Visitor<'tcx> for CostChecker<'_, 'tcx> {
fn visit_rvalue(&mut self, rvalue: &Rvalue<'tcx>, _location: Location) {
match rvalue {
Rvalue::NullaryOp(NullOp::UbChecks, ..) if !self.tcx.sess.ub_checks() => {
Rvalue::NullaryOp(NullOp::UbChecks, ..)
if !self
.tcx
.sess
.opts
.unstable_opts
.inline_mir_preserve_debug
.unwrap_or(self.tcx.sess.ub_checks()) =>
{
// If this is in optimized MIR it's because it's used later,
// so if we don't need UB checks this session, give a bonus
// here to offset the cost of the call later.
@ -111,12 +119,19 @@ impl<'tcx> Visitor<'tcx> for CostChecker<'_, 'tcx> {
}
}
TerminatorKind::Assert { unwind, msg, .. } => {
self.penalty +=
if msg.is_optional_overflow_check() && !self.tcx.sess.overflow_checks() {
INSTR_COST
} else {
CALL_PENALTY
};
self.penalty += if msg.is_optional_overflow_check()
&& !self
.tcx
.sess
.opts
.unstable_opts
.inline_mir_preserve_debug
.unwrap_or(self.tcx.sess.overflow_checks())
{
INSTR_COST
} else {
CALL_PENALTY
};
if let UnwindAction::Cleanup(_) = unwind {
self.penalty += LANDINGPAD_PENALTY;
}

View File

@ -7,19 +7,90 @@ fn reverse_loop(_1: &[T], _2: impl Fn(&T)) -> () {
let mut _11: std::slice::Iter<'_, T>;
let mut _12: std::iter::Rev<std::slice::Iter<'_, T>>;
let mut _13: std::iter::Rev<std::slice::Iter<'_, T>>;
let mut _15: std::option::Option<&T>;
let mut _16: isize;
let mut _18: &impl Fn(&T);
let mut _19: (&T,);
let _20: ();
let mut _37: std::option::Option<&T>;
let mut _39: &impl Fn(&T);
let mut _40: (&T,);
let _41: ();
scope 1 {
debug iter => _13;
let _17: &T;
let _38: &T;
scope 2 {
debug x => _17;
debug x => _38;
}
scope 17 (inlined <Rev<std::slice::Iter<'_, T>> as Iterator>::next) {
let mut _14: &mut std::slice::Iter<'_, T>;
scope 18 (inlined <std::slice::Iter<'_, T> as DoubleEndedIterator>::next_back) {
let mut _14: *const *const T;
let mut _15: *const std::ptr::NonNull<T>;
let mut _20: bool;
let mut _21: *const T;
let _36: &T;
scope 19 {
let _16: std::ptr::NonNull<T>;
let _22: usize;
scope 20 {
}
scope 21 {
scope 25 (inlined <NonNull<T> as PartialEq>::eq) {
let mut _17: std::ptr::NonNull<T>;
scope 26 (inlined NonNull::<T>::as_ptr) {
let mut _18: *const T;
}
scope 27 (inlined NonNull::<T>::as_ptr) {
let mut _19: *const T;
}
}
}
scope 22 (inlined std::ptr::const_ptr::<impl *const T>::addr) {
scope 23 (inlined std::ptr::const_ptr::<impl *const T>::cast::<()>) {
}
}
scope 24 (inlined std::ptr::const_ptr::<impl *const *const T>::cast::<NonNull<T>>) {
}
}
scope 28 (inlined std::slice::Iter::<'_, T>::next_back_unchecked) {
let _29: std::ptr::NonNull<T>;
scope 29 (inlined std::slice::Iter::<'_, T>::pre_dec_end) {
let mut _23: *mut *const T;
let mut _24: *mut std::ptr::NonNull<T>;
let mut _25: std::ptr::NonNull<T>;
let mut _28: std::ptr::NonNull<T>;
let mut _30: *mut *const T;
let mut _31: *mut usize;
let mut _32: usize;
let mut _33: usize;
scope 30 {
scope 31 {
}
scope 32 {
scope 35 (inlined NonNull::<T>::sub) {
scope 36 (inlined core::num::<impl isize>::unchecked_neg) {
scope 37 (inlined core::ub_checks::check_language_ub) {
scope 38 (inlined core::ub_checks::check_language_ub::runtime) {
}
}
}
scope 39 (inlined NonNull::<T>::offset) {
let mut _26: *const T;
let mut _27: *const T;
}
}
}
scope 33 (inlined std::ptr::mut_ptr::<impl *mut *const T>::cast::<usize>) {
}
scope 34 (inlined std::ptr::mut_ptr::<impl *mut *const T>::cast::<NonNull<T>>) {
}
}
}
scope 40 (inlined NonNull::<T>::as_ref::<'_>) {
let mut _34: std::ptr::NonNull<T>;
scope 41 (inlined NonNull::<T>::as_ptr) {
let mut _35: *const T;
}
scope 42 (inlined std::ptr::mut_ptr::<impl *mut T>::cast_const) {
}
}
}
}
}
}
scope 3 (inlined core::slice::<impl [T]>::iter) {
@ -107,45 +178,147 @@ fn reverse_loop(_1: &[T], _2: impl Fn(&T)) -> () {
}
bb4: {
StorageLive(_15);
StorageLive(_14);
_14 = &mut (_13.0: std::slice::Iter<'_, T>);
_15 = <std::slice::Iter<'_, T> as DoubleEndedIterator>::next_back(move _14) -> [return: bb5, unwind unreachable];
StorageLive(_37);
StorageLive(_22);
StorageLive(_21);
StorageLive(_16);
StorageLive(_36);
StorageLive(_20);
switchInt(const <T as std::mem::SizedTypeProperties>::IS_ZST) -> [0: bb5, otherwise: bb6];
}
bb5: {
StorageLive(_15);
StorageLive(_14);
_14 = &raw const ((_13.0: std::slice::Iter<'_, T>).1: *const T);
_15 = _14 as *const std::ptr::NonNull<T> (PtrToPtr);
StorageDead(_14);
_16 = discriminant(_15);
switchInt(move _16) -> [0: bb6, 1: bb8, otherwise: bb10];
_16 = (*_15);
StorageDead(_15);
StorageLive(_18);
StorageLive(_19);
StorageLive(_17);
_17 = ((_13.0: std::slice::Iter<'_, T>).0: std::ptr::NonNull<T>);
_18 = (_17.0: *const T);
StorageDead(_17);
_19 = (_16.0: *const T);
_20 = Eq(_18, _19);
StorageDead(_19);
StorageDead(_18);
goto -> bb7;
}
bb6: {
StorageDead(_15);
StorageDead(_13);
drop(_2) -> [return: bb7, unwind unreachable];
_21 = ((_13.0: std::slice::Iter<'_, T>).1: *const T);
_22 = _21 as usize (Transmute);
_20 = Eq(_22, const 0_usize);
goto -> bb7;
}
bb7: {
return;
switchInt(move _20) -> [0: bb8, otherwise: bb16];
}
bb8: {
_17 = ((_15 as Some).0: &T);
StorageLive(_18);
_18 = &_2;
StorageLive(_19);
_19 = (_17,);
_20 = <impl Fn(&T) as Fn<(&T,)>>::call(move _18, move _19) -> [return: bb9, unwind unreachable];
StorageLive(_35);
StorageLive(_29);
StorageLive(_31);
StorageLive(_24);
switchInt(const <T as std::mem::SizedTypeProperties>::IS_ZST) -> [0: bb9, otherwise: bb13];
}
bb9: {
StorageDead(_19);
StorageDead(_18);
StorageDead(_15);
goto -> bb4;
StorageLive(_23);
_23 = &raw mut ((_13.0: std::slice::Iter<'_, T>).1: *const T);
_24 = _23 as *mut std::ptr::NonNull<T> (PtrToPtr);
StorageDead(_23);
StorageLive(_28);
_25 = (*_24);
switchInt(const <T as std::mem::SizedTypeProperties>::IS_ZST) -> [0: bb10, otherwise: bb11];
}
bb10: {
unreachable;
StorageLive(_27);
StorageLive(_26);
_26 = (_25.0: *const T);
_27 = Offset(move _26, const -1_isize);
StorageDead(_26);
_28 = NonNull::<T> { pointer: move _27 };
StorageDead(_27);
goto -> bb12;
}
bb11: {
_28 = _25;
goto -> bb12;
}
bb12: {
(*_24) = move _28;
StorageDead(_28);
_29 = (*_24);
goto -> bb14;
}
bb13: {
StorageLive(_30);
_30 = &raw mut ((_13.0: std::slice::Iter<'_, T>).1: *const T);
_31 = _30 as *mut usize (PtrToPtr);
StorageDead(_30);
StorageLive(_33);
StorageLive(_32);
_32 = (*_31);
_33 = SubUnchecked(move _32, const 1_usize);
StorageDead(_32);
(*_31) = move _33;
StorageDead(_33);
_29 = ((_13.0: std::slice::Iter<'_, T>).0: std::ptr::NonNull<T>);
goto -> bb14;
}
bb14: {
StorageDead(_24);
StorageDead(_31);
StorageLive(_34);
_34 = _29;
_35 = (_34.0: *const T);
StorageDead(_34);
_36 = &(*_35);
StorageDead(_29);
StorageDead(_35);
_37 = Option::<&T>::Some(_36);
StorageDead(_20);
StorageDead(_36);
StorageDead(_16);
StorageDead(_21);
StorageDead(_22);
_38 = ((_37 as Some).0: &T);
StorageLive(_39);
_39 = &_2;
StorageLive(_40);
_40 = (_38,);
_41 = <impl Fn(&T) as Fn<(&T,)>>::call(move _39, move _40) -> [return: bb15, unwind unreachable];
}
bb15: {
StorageDead(_40);
StorageDead(_39);
StorageDead(_37);
goto -> bb4;
}
bb16: {
StorageDead(_20);
StorageDead(_36);
StorageDead(_16);
StorageDead(_21);
StorageDead(_22);
StorageDead(_37);
StorageDead(_13);
drop(_2) -> [return: bb17, unwind unreachable];
}
bb17: {
return;
}
}

View File

@ -7,19 +7,90 @@ fn reverse_loop(_1: &[T], _2: impl Fn(&T)) -> () {
let mut _11: std::slice::Iter<'_, T>;
let mut _12: std::iter::Rev<std::slice::Iter<'_, T>>;
let mut _13: std::iter::Rev<std::slice::Iter<'_, T>>;
let mut _15: std::option::Option<&T>;
let mut _16: isize;
let mut _18: &impl Fn(&T);
let mut _19: (&T,);
let _20: ();
let mut _37: std::option::Option<&T>;
let mut _39: &impl Fn(&T);
let mut _40: (&T,);
let _41: ();
scope 1 {
debug iter => _13;
let _17: &T;
let _38: &T;
scope 2 {
debug x => _17;
debug x => _38;
}
scope 17 (inlined <Rev<std::slice::Iter<'_, T>> as Iterator>::next) {
let mut _14: &mut std::slice::Iter<'_, T>;
scope 18 (inlined <std::slice::Iter<'_, T> as DoubleEndedIterator>::next_back) {
let mut _14: *const *const T;
let mut _15: *const std::ptr::NonNull<T>;
let mut _20: bool;
let mut _21: *const T;
let _36: &T;
scope 19 {
let _16: std::ptr::NonNull<T>;
let _22: usize;
scope 20 {
}
scope 21 {
scope 25 (inlined <NonNull<T> as PartialEq>::eq) {
let mut _17: std::ptr::NonNull<T>;
scope 26 (inlined NonNull::<T>::as_ptr) {
let mut _18: *const T;
}
scope 27 (inlined NonNull::<T>::as_ptr) {
let mut _19: *const T;
}
}
}
scope 22 (inlined std::ptr::const_ptr::<impl *const T>::addr) {
scope 23 (inlined std::ptr::const_ptr::<impl *const T>::cast::<()>) {
}
}
scope 24 (inlined std::ptr::const_ptr::<impl *const *const T>::cast::<NonNull<T>>) {
}
}
scope 28 (inlined std::slice::Iter::<'_, T>::next_back_unchecked) {
let _29: std::ptr::NonNull<T>;
scope 29 (inlined std::slice::Iter::<'_, T>::pre_dec_end) {
let mut _23: *mut *const T;
let mut _24: *mut std::ptr::NonNull<T>;
let mut _25: std::ptr::NonNull<T>;
let mut _28: std::ptr::NonNull<T>;
let mut _30: *mut *const T;
let mut _31: *mut usize;
let mut _32: usize;
let mut _33: usize;
scope 30 {
scope 31 {
}
scope 32 {
scope 35 (inlined NonNull::<T>::sub) {
scope 36 (inlined core::num::<impl isize>::unchecked_neg) {
scope 37 (inlined core::ub_checks::check_language_ub) {
scope 38 (inlined core::ub_checks::check_language_ub::runtime) {
}
}
}
scope 39 (inlined NonNull::<T>::offset) {
let mut _26: *const T;
let mut _27: *const T;
}
}
}
scope 33 (inlined std::ptr::mut_ptr::<impl *mut *const T>::cast::<usize>) {
}
scope 34 (inlined std::ptr::mut_ptr::<impl *mut *const T>::cast::<NonNull<T>>) {
}
}
}
scope 40 (inlined NonNull::<T>::as_ref::<'_>) {
let mut _34: std::ptr::NonNull<T>;
scope 41 (inlined NonNull::<T>::as_ptr) {
let mut _35: *const T;
}
scope 42 (inlined std::ptr::mut_ptr::<impl *mut T>::cast_const) {
}
}
}
}
}
}
scope 3 (inlined core::slice::<impl [T]>::iter) {
@ -107,53 +178,155 @@ fn reverse_loop(_1: &[T], _2: impl Fn(&T)) -> () {
}
bb4: {
StorageLive(_15);
StorageLive(_14);
_14 = &mut (_13.0: std::slice::Iter<'_, T>);
_15 = <std::slice::Iter<'_, T> as DoubleEndedIterator>::next_back(move _14) -> [return: bb5, unwind: bb11];
StorageLive(_37);
StorageLive(_22);
StorageLive(_21);
StorageLive(_16);
StorageLive(_36);
StorageLive(_20);
switchInt(const <T as std::mem::SizedTypeProperties>::IS_ZST) -> [0: bb5, otherwise: bb6];
}
bb5: {
StorageLive(_15);
StorageLive(_14);
_14 = &raw const ((_13.0: std::slice::Iter<'_, T>).1: *const T);
_15 = _14 as *const std::ptr::NonNull<T> (PtrToPtr);
StorageDead(_14);
_16 = discriminant(_15);
switchInt(move _16) -> [0: bb6, 1: bb8, otherwise: bb10];
_16 = (*_15);
StorageDead(_15);
StorageLive(_18);
StorageLive(_19);
StorageLive(_17);
_17 = ((_13.0: std::slice::Iter<'_, T>).0: std::ptr::NonNull<T>);
_18 = (_17.0: *const T);
StorageDead(_17);
_19 = (_16.0: *const T);
_20 = Eq(_18, _19);
StorageDead(_19);
StorageDead(_18);
goto -> bb7;
}
bb6: {
StorageDead(_15);
StorageDead(_13);
drop(_2) -> [return: bb7, unwind continue];
_21 = ((_13.0: std::slice::Iter<'_, T>).1: *const T);
_22 = _21 as usize (Transmute);
_20 = Eq(_22, const 0_usize);
goto -> bb7;
}
bb7: {
return;
switchInt(move _20) -> [0: bb8, otherwise: bb18];
}
bb8: {
_17 = ((_15 as Some).0: &T);
StorageLive(_18);
_18 = &_2;
StorageLive(_19);
_19 = (_17,);
_20 = <impl Fn(&T) as Fn<(&T,)>>::call(move _18, move _19) -> [return: bb9, unwind: bb11];
StorageLive(_35);
StorageLive(_29);
StorageLive(_31);
StorageLive(_24);
switchInt(const <T as std::mem::SizedTypeProperties>::IS_ZST) -> [0: bb9, otherwise: bb13];
}
bb9: {
StorageDead(_19);
StorageDead(_18);
StorageDead(_15);
goto -> bb4;
StorageLive(_23);
_23 = &raw mut ((_13.0: std::slice::Iter<'_, T>).1: *const T);
_24 = _23 as *mut std::ptr::NonNull<T> (PtrToPtr);
StorageDead(_23);
StorageLive(_28);
_25 = (*_24);
switchInt(const <T as std::mem::SizedTypeProperties>::IS_ZST) -> [0: bb10, otherwise: bb11];
}
bb10: {
unreachable;
StorageLive(_27);
StorageLive(_26);
_26 = (_25.0: *const T);
_27 = Offset(move _26, const -1_isize);
StorageDead(_26);
_28 = NonNull::<T> { pointer: move _27 };
StorageDead(_27);
goto -> bb12;
}
bb11 (cleanup): {
drop(_2) -> [return: bb12, unwind terminate(cleanup)];
bb11: {
_28 = _25;
goto -> bb12;
}
bb12 (cleanup): {
bb12: {
(*_24) = move _28;
StorageDead(_28);
_29 = (*_24);
goto -> bb14;
}
bb13: {
StorageLive(_30);
_30 = &raw mut ((_13.0: std::slice::Iter<'_, T>).1: *const T);
_31 = _30 as *mut usize (PtrToPtr);
StorageDead(_30);
StorageLive(_33);
StorageLive(_32);
_32 = (*_31);
_33 = SubUnchecked(move _32, const 1_usize);
StorageDead(_32);
(*_31) = move _33;
StorageDead(_33);
_29 = ((_13.0: std::slice::Iter<'_, T>).0: std::ptr::NonNull<T>);
goto -> bb14;
}
bb14: {
StorageDead(_24);
StorageDead(_31);
StorageLive(_34);
_34 = _29;
_35 = (_34.0: *const T);
StorageDead(_34);
_36 = &(*_35);
StorageDead(_29);
StorageDead(_35);
_37 = Option::<&T>::Some(_36);
StorageDead(_20);
StorageDead(_36);
StorageDead(_16);
StorageDead(_21);
StorageDead(_22);
_38 = ((_37 as Some).0: &T);
StorageLive(_39);
_39 = &_2;
StorageLive(_40);
_40 = (_38,);
_41 = <impl Fn(&T) as Fn<(&T,)>>::call(move _39, move _40) -> [return: bb15, unwind: bb16];
}
bb15: {
StorageDead(_40);
StorageDead(_39);
StorageDead(_37);
goto -> bb4;
}
bb16 (cleanup): {
drop(_2) -> [return: bb17, unwind terminate(cleanup)];
}
bb17 (cleanup): {
resume;
}
bb18: {
StorageDead(_20);
StorageDead(_36);
StorageDead(_16);
StorageDead(_21);
StorageDead(_22);
StorageDead(_37);
StorageDead(_13);
drop(_2) -> [return: bb19, unwind continue];
}
bb19: {
return;
}
}

View File

@ -1,5 +1,6 @@
// skip-filecheck
//@ compile-flags: -O -C debuginfo=0 -Zmir-opt-level=2
//@ only-64bit (constants for `None::<&T>` show in the output)
// EMIT_MIR_FOR_EACH_PANIC_STRATEGY
#![crate_type = "lib"]

View File

@ -3,12 +3,205 @@
fn slice_iter_mut_next_back(_1: &mut std::slice::IterMut<'_, T>) -> Option<&mut T> {
debug it => _1;
let mut _0: std::option::Option<&mut T>;
scope 1 (inlined <std::slice::IterMut<'_, T> as DoubleEndedIterator>::next_back) {
let mut _2: *const *mut T;
let mut _3: *const std::ptr::NonNull<T>;
let mut _8: bool;
let mut _9: *mut T;
let mut _25: &mut T;
scope 2 {
let _4: std::ptr::NonNull<T>;
let _10: usize;
scope 3 {
}
scope 4 {
scope 8 (inlined <NonNull<T> as PartialEq>::eq) {
let mut _5: std::ptr::NonNull<T>;
scope 9 (inlined NonNull::<T>::as_ptr) {
let mut _6: *const T;
}
scope 10 (inlined NonNull::<T>::as_ptr) {
let mut _7: *const T;
}
}
}
scope 5 (inlined std::ptr::mut_ptr::<impl *mut T>::addr) {
scope 6 (inlined std::ptr::mut_ptr::<impl *mut T>::cast::<()>) {
}
}
scope 7 (inlined std::ptr::const_ptr::<impl *const *mut T>::cast::<NonNull<T>>) {
}
}
scope 11 (inlined std::slice::IterMut::<'_, T>::next_back_unchecked) {
let mut _17: std::ptr::NonNull<T>;
scope 12 (inlined std::slice::IterMut::<'_, T>::pre_dec_end) {
let mut _11: *mut *mut T;
let mut _12: *mut std::ptr::NonNull<T>;
let mut _13: std::ptr::NonNull<T>;
let mut _16: std::ptr::NonNull<T>;
let mut _18: *mut *mut T;
let mut _19: *mut usize;
let mut _20: usize;
let mut _21: usize;
scope 13 {
scope 14 {
}
scope 15 {
scope 18 (inlined NonNull::<T>::sub) {
scope 19 (inlined core::num::<impl isize>::unchecked_neg) {
scope 20 (inlined core::ub_checks::check_language_ub) {
scope 21 (inlined core::ub_checks::check_language_ub::runtime) {
}
}
}
scope 22 (inlined NonNull::<T>::offset) {
let mut _14: *const T;
let mut _15: *const T;
}
}
}
scope 16 (inlined std::ptr::mut_ptr::<impl *mut *mut T>::cast::<usize>) {
}
scope 17 (inlined std::ptr::mut_ptr::<impl *mut *mut T>::cast::<NonNull<T>>) {
}
}
}
scope 23 (inlined NonNull::<T>::as_mut::<'_>) {
let mut _22: std::ptr::NonNull<T>;
let mut _24: *mut T;
scope 24 (inlined NonNull::<T>::as_ptr) {
let mut _23: *const T;
}
}
}
}
bb0: {
_0 = <std::slice::IterMut<'_, T> as DoubleEndedIterator>::next_back(move _1) -> [return: bb1, unwind unreachable];
StorageLive(_10);
StorageLive(_9);
StorageLive(_4);
StorageLive(_25);
StorageLive(_8);
switchInt(const <T as std::mem::SizedTypeProperties>::IS_ZST) -> [0: bb1, otherwise: bb2];
}
bb1: {
StorageLive(_3);
StorageLive(_2);
_2 = &raw const ((*_1).1: *mut T);
_3 = _2 as *const std::ptr::NonNull<T> (PtrToPtr);
StorageDead(_2);
_4 = (*_3);
StorageDead(_3);
StorageLive(_6);
StorageLive(_7);
StorageLive(_5);
_5 = ((*_1).0: std::ptr::NonNull<T>);
_6 = (_5.0: *const T);
StorageDead(_5);
_7 = (_4.0: *const T);
_8 = Eq(_6, _7);
StorageDead(_7);
StorageDead(_6);
goto -> bb3;
}
bb2: {
_9 = ((*_1).1: *mut T);
_10 = _9 as usize (Transmute);
_8 = Eq(_10, const 0_usize);
goto -> bb3;
}
bb3: {
switchInt(move _8) -> [0: bb4, otherwise: bb11];
}
bb4: {
StorageLive(_24);
StorageLive(_17);
StorageLive(_19);
StorageLive(_12);
switchInt(const <T as std::mem::SizedTypeProperties>::IS_ZST) -> [0: bb5, otherwise: bb9];
}
bb5: {
StorageLive(_11);
_11 = &raw mut ((*_1).1: *mut T);
_12 = _11 as *mut std::ptr::NonNull<T> (PtrToPtr);
StorageDead(_11);
StorageLive(_16);
_13 = (*_12);
switchInt(const <T as std::mem::SizedTypeProperties>::IS_ZST) -> [0: bb6, otherwise: bb7];
}
bb6: {
StorageLive(_15);
StorageLive(_14);
_14 = (_13.0: *const T);
_15 = Offset(move _14, const -1_isize);
StorageDead(_14);
_16 = NonNull::<T> { pointer: move _15 };
StorageDead(_15);
goto -> bb8;
}
bb7: {
_16 = _13;
goto -> bb8;
}
bb8: {
(*_12) = move _16;
StorageDead(_16);
_17 = (*_12);
goto -> bb10;
}
bb9: {
StorageLive(_18);
_18 = &raw mut ((*_1).1: *mut T);
_19 = _18 as *mut usize (PtrToPtr);
StorageDead(_18);
StorageLive(_21);
StorageLive(_20);
_20 = (*_19);
_21 = SubUnchecked(move _20, const 1_usize);
StorageDead(_20);
(*_19) = move _21;
StorageDead(_21);
_17 = ((*_1).0: std::ptr::NonNull<T>);
goto -> bb10;
}
bb10: {
StorageDead(_12);
StorageDead(_19);
StorageLive(_22);
_22 = _17;
StorageLive(_23);
_23 = (_22.0: *const T);
_24 = move _23 as *mut T (PtrToPtr);
StorageDead(_23);
StorageDead(_22);
_25 = &mut (*_24);
StorageDead(_17);
StorageDead(_24);
_0 = Option::<&mut T>::Some(_25);
goto -> bb12;
}
bb11: {
_0 = const {transmute(0x0000000000000000): Option<&mut T>};
goto -> bb12;
}
bb12: {
StorageDead(_8);
StorageDead(_25);
StorageDead(_4);
StorageDead(_9);
StorageDead(_10);
return;
}
}

View File

@ -3,12 +3,205 @@
fn slice_iter_mut_next_back(_1: &mut std::slice::IterMut<'_, T>) -> Option<&mut T> {
debug it => _1;
let mut _0: std::option::Option<&mut T>;
scope 1 (inlined <std::slice::IterMut<'_, T> as DoubleEndedIterator>::next_back) {
let mut _2: *const *mut T;
let mut _3: *const std::ptr::NonNull<T>;
let mut _8: bool;
let mut _9: *mut T;
let mut _25: &mut T;
scope 2 {
let _4: std::ptr::NonNull<T>;
let _10: usize;
scope 3 {
}
scope 4 {
scope 8 (inlined <NonNull<T> as PartialEq>::eq) {
let mut _5: std::ptr::NonNull<T>;
scope 9 (inlined NonNull::<T>::as_ptr) {
let mut _6: *const T;
}
scope 10 (inlined NonNull::<T>::as_ptr) {
let mut _7: *const T;
}
}
}
scope 5 (inlined std::ptr::mut_ptr::<impl *mut T>::addr) {
scope 6 (inlined std::ptr::mut_ptr::<impl *mut T>::cast::<()>) {
}
}
scope 7 (inlined std::ptr::const_ptr::<impl *const *mut T>::cast::<NonNull<T>>) {
}
}
scope 11 (inlined std::slice::IterMut::<'_, T>::next_back_unchecked) {
let mut _17: std::ptr::NonNull<T>;
scope 12 (inlined std::slice::IterMut::<'_, T>::pre_dec_end) {
let mut _11: *mut *mut T;
let mut _12: *mut std::ptr::NonNull<T>;
let mut _13: std::ptr::NonNull<T>;
let mut _16: std::ptr::NonNull<T>;
let mut _18: *mut *mut T;
let mut _19: *mut usize;
let mut _20: usize;
let mut _21: usize;
scope 13 {
scope 14 {
}
scope 15 {
scope 18 (inlined NonNull::<T>::sub) {
scope 19 (inlined core::num::<impl isize>::unchecked_neg) {
scope 20 (inlined core::ub_checks::check_language_ub) {
scope 21 (inlined core::ub_checks::check_language_ub::runtime) {
}
}
}
scope 22 (inlined NonNull::<T>::offset) {
let mut _14: *const T;
let mut _15: *const T;
}
}
}
scope 16 (inlined std::ptr::mut_ptr::<impl *mut *mut T>::cast::<usize>) {
}
scope 17 (inlined std::ptr::mut_ptr::<impl *mut *mut T>::cast::<NonNull<T>>) {
}
}
}
scope 23 (inlined NonNull::<T>::as_mut::<'_>) {
let mut _22: std::ptr::NonNull<T>;
let mut _24: *mut T;
scope 24 (inlined NonNull::<T>::as_ptr) {
let mut _23: *const T;
}
}
}
}
bb0: {
_0 = <std::slice::IterMut<'_, T> as DoubleEndedIterator>::next_back(move _1) -> [return: bb1, unwind continue];
StorageLive(_10);
StorageLive(_9);
StorageLive(_4);
StorageLive(_25);
StorageLive(_8);
switchInt(const <T as std::mem::SizedTypeProperties>::IS_ZST) -> [0: bb1, otherwise: bb2];
}
bb1: {
StorageLive(_3);
StorageLive(_2);
_2 = &raw const ((*_1).1: *mut T);
_3 = _2 as *const std::ptr::NonNull<T> (PtrToPtr);
StorageDead(_2);
_4 = (*_3);
StorageDead(_3);
StorageLive(_6);
StorageLive(_7);
StorageLive(_5);
_5 = ((*_1).0: std::ptr::NonNull<T>);
_6 = (_5.0: *const T);
StorageDead(_5);
_7 = (_4.0: *const T);
_8 = Eq(_6, _7);
StorageDead(_7);
StorageDead(_6);
goto -> bb3;
}
bb2: {
_9 = ((*_1).1: *mut T);
_10 = _9 as usize (Transmute);
_8 = Eq(_10, const 0_usize);
goto -> bb3;
}
bb3: {
switchInt(move _8) -> [0: bb4, otherwise: bb11];
}
bb4: {
StorageLive(_24);
StorageLive(_17);
StorageLive(_19);
StorageLive(_12);
switchInt(const <T as std::mem::SizedTypeProperties>::IS_ZST) -> [0: bb5, otherwise: bb9];
}
bb5: {
StorageLive(_11);
_11 = &raw mut ((*_1).1: *mut T);
_12 = _11 as *mut std::ptr::NonNull<T> (PtrToPtr);
StorageDead(_11);
StorageLive(_16);
_13 = (*_12);
switchInt(const <T as std::mem::SizedTypeProperties>::IS_ZST) -> [0: bb6, otherwise: bb7];
}
bb6: {
StorageLive(_15);
StorageLive(_14);
_14 = (_13.0: *const T);
_15 = Offset(move _14, const -1_isize);
StorageDead(_14);
_16 = NonNull::<T> { pointer: move _15 };
StorageDead(_15);
goto -> bb8;
}
bb7: {
_16 = _13;
goto -> bb8;
}
bb8: {
(*_12) = move _16;
StorageDead(_16);
_17 = (*_12);
goto -> bb10;
}
bb9: {
StorageLive(_18);
_18 = &raw mut ((*_1).1: *mut T);
_19 = _18 as *mut usize (PtrToPtr);
StorageDead(_18);
StorageLive(_21);
StorageLive(_20);
_20 = (*_19);
_21 = SubUnchecked(move _20, const 1_usize);
StorageDead(_20);
(*_19) = move _21;
StorageDead(_21);
_17 = ((*_1).0: std::ptr::NonNull<T>);
goto -> bb10;
}
bb10: {
StorageDead(_12);
StorageDead(_19);
StorageLive(_22);
_22 = _17;
StorageLive(_23);
_23 = (_22.0: *const T);
_24 = move _23 as *mut T (PtrToPtr);
StorageDead(_23);
StorageDead(_22);
_25 = &mut (*_24);
StorageDead(_17);
StorageDead(_24);
_0 = Option::<&mut T>::Some(_25);
goto -> bb12;
}
bb11: {
_0 = const {transmute(0x0000000000000000): Option<&mut T>};
goto -> bb12;
}
bb12: {
StorageDead(_8);
StorageDead(_25);
StorageDead(_4);
StorageDead(_9);
StorageDead(_10);
return;
}
}