diff --git a/core/src/intrinsics.rs b/core/src/intrinsics.rs
index c4c6388338949..240cc8a21ff79 100644
--- a/core/src/intrinsics.rs
+++ b/core/src/intrinsics.rs
@@ -1010,6 +1010,34 @@ pub const fn unlikely(b: bool) -> bool {
     b
 }
 
+/// Returns either `true_val` or `false_val` depending on condition `b` with a
+/// hint to the compiler that this condition is unlikely to be correctly
+/// predicted by a CPU's branch predictor (e.g. a binary search).
+///
+/// This is otherwise functionally equivalent to `if b { true_val } else { false_val }`.
+///
+/// Note that, unlike most intrinsics, this is safe to call;
+/// it does not require an `unsafe` block.
+/// Therefore, implementations must not require the user to uphold
+/// any safety invariants.
+///
+/// This intrinsic does not have a stable counterpart.
+#[cfg(not(bootstrap))]
+#[unstable(feature = "core_intrinsics", issue = "none")]
+#[rustc_intrinsic]
+#[rustc_nounwind]
+#[miri::intrinsic_fallback_is_spec]
+#[inline]
+pub fn select_unpredictable<T>(b: bool, true_val: T, false_val: T) -> T {
+    if b { true_val } else { false_val }
+}
+
+#[cfg(bootstrap)]
+#[inline]
+pub fn select_unpredictable<T>(b: bool, true_val: T, false_val: T) -> T {
+    if b { true_val } else { false_val }
+}
+
 extern "rust-intrinsic" {
     /// Executes a breakpoint trap, for inspection by a debugger.
     ///