libs: use `assert_unchecked` instead of intrinsic

8 files changed, 12 insertions, 9 deletions

diff --git a/library/core/src/alloc/global.rs b/library/core/src/alloc/global.rs
index c582111701a..a1fff6707bd 100644
--- a/library/core/src/alloc/global.rs
+++ b/library/core/src/alloc/global.rs
@@ -110,7 +110,7 @@ use crate::ptr;
 ///   ```rust,ignore (unsound and has placeholders)
 ///   drop(Box::new(42));
 ///   let number_of_heap_allocs = /* call private allocator API */;
-///   unsafe { std::intrinsics::assume(number_of_heap_allocs > 0); }
+///   unsafe { std::hint::assert_unchecked(number_of_heap_allocs > 0); }
 ///   ```
 ///
 ///   Note that the optimizations mentioned above are not the only
diff --git a/library/core/src/lib.rs b/library/core/src/lib.rs
index 1a8f245c8be..d0f89efa518 100644
--- a/library/core/src/lib.rs
+++ b/library/core/src/lib.rs
@@ -131,6 +131,7 @@
 #![feature(const_fmt_arguments_new)]
 #![feature(const_hash)]
 #![feature(const_heap)]
+#![feature(const_hint_assert_unchecked)]
 #![feature(const_index_range_slice_index)]
 #![feature(const_int_unchecked_arith)]
 #![feature(const_intrinsic_forget)]
diff --git a/library/core/src/num/mod.rs b/library/core/src/num/mod.rs
index 695e87aaabf..2e683592b46 100644
--- a/library/core/src/num/mod.rs
+++ b/library/core/src/num/mod.rs
@@ -3,6 +3,7 @@
 #![stable(feature = "rust1", since = "1.0.0")]
 
 use crate::ascii;
+use crate::hint;
 use crate::intrinsics;
 use crate::mem;
 use crate::ops::{Add, Mul, Sub};
diff --git a/library/core/src/num/uint_macros.rs b/library/core/src/num/uint_macros.rs
index 11a53aaf122..62d6015fafe 100644
--- a/library/core/src/num/uint_macros.rs
+++ b/library/core/src/num/uint_macros.rs
@@ -2036,8 +2036,8 @@ macro_rules! uint_impl {
             // SAFETY: the result is positive and fits in an integer with half as many bits.
             // Inform the optimizer about it.
             unsafe {
-                intrinsics::assume(0 < res);
-                intrinsics::assume(res < 1 << (Self::BITS / 2));
+                hint::assert_unchecked(0 < res);
+                hint::assert_unchecked(res < 1 << (Self::BITS / 2));
             }
 
             res
diff --git a/library/core/src/slice/index.rs b/library/core/src/slice/index.rs
index 373b4aee47a..fb9be396eab 100644
--- a/library/core/src/slice/index.rs
+++ b/library/core/src/slice/index.rs
@@ -234,7 +234,7 @@ unsafe impl<T> SliceIndex<[T]> for usize {
         // `self` is in bounds of `slice` so `self` cannot overflow an `isize`,
         // so the call to `add` is safe.
         unsafe {
-            crate::intrinsics::assume(self < slice.len());
+            crate::hint::assert_unchecked(self < slice.len());
             slice.as_ptr().add(self)
         }
     }
diff --git a/library/core/src/slice/iter.rs b/library/core/src/slice/iter.rs
index 3d58afd26ea..e1d19fef35f 100644
--- a/library/core/src/slice/iter.rs
+++ b/library/core/src/slice/iter.rs
@@ -6,7 +6,7 @@ mod macros;
 use crate::cmp;
 use crate::cmp::Ordering;
 use crate::fmt;
-use crate::intrinsics::assume;
+use crate::hint::assert_unchecked;
 use crate::iter::{
     FusedIterator, TrustedLen, TrustedRandomAccess, TrustedRandomAccessNoCoerce, UncheckedIterator,
 };
diff --git a/library/core/src/slice/iter/macros.rs b/library/core/src/slice/iter/macros.rs
index 95bcd123b82..fc6af45fb90 100644
--- a/library/core/src/slice/iter/macros.rs
+++ b/library/core/src/slice/iter/macros.rs
@@ -338,7 +338,7 @@ macro_rules! iterator {
                     if predicate(x) {
                         // SAFETY: we are guaranteed to be in bounds by the loop invariant:
                         // when `i >= n`, `self.next()` returns `None` and the loop breaks.
-                        unsafe { assume(i < n) };
+                        unsafe { assert_unchecked(i < n) };
                         return Some(i);
                     }
                     i += 1;
@@ -361,7 +361,7 @@ macro_rules! iterator {
                     if predicate(x) {
                         // SAFETY: `i` must be lower than `n` since it starts at `n`
                         // and is only decreasing.
-                        unsafe { assume(i < n) };
+                        unsafe { assert_unchecked(i < n) };
                         return Some(i);
                     }
                 }
diff --git a/library/core/src/slice/mod.rs b/library/core/src/slice/mod.rs
index 5edc89e4cb5..e971f933570 100644
--- a/library/core/src/slice/mod.rs
+++ b/library/core/src/slice/mod.rs
@@ -8,6 +8,7 @@
 
 use crate::cmp::Ordering::{self, Equal, Greater, Less};
 use crate::fmt;
+use crate::hint;
 use crate::intrinsics::exact_div;
 use crate::mem::{self, SizedTypeProperties};
 use crate::num::NonZeroUsize;
@@ -2850,7 +2851,7 @@ impl<T> [T] {
             right = if cmp == Greater { mid } else { right };
             if cmp == Equal {
                 // SAFETY: same as the `get_unchecked` above
-                unsafe { crate::intrinsics::assume(mid < self.len()) };
+                unsafe { hint::assert_unchecked(mid < self.len()) };
                 return Ok(mid);
             }
 
@@ -2859,7 +2860,7 @@ impl<T> [T] {
 
         // SAFETY: directly true from the overall invariant.
         // Note that this is `<=`, unlike the assume in the `Ok` path.
-        unsafe { crate::intrinsics::assume(left <= self.len()) };
+        unsafe { hint::assert_unchecked(left <= self.len()) };
         Err(left)
     }