Merge pull request #18909 from Veykril/push-rrpprwwzttkt

Use `strict_provenance`

Author: Veykril

Diff for: Cargo.lock

@@ -4,7 +4,7 @@ exclude = ["crates/proc-macro-srv/proc-macro-test/imp"]
 resolver = "2"
 
 [workspace.package]
-rust-version = "1.83"
+rust-version = "1.84"
 edition = "2021"
 license = "MIT OR Apache-2.0"
 authors = ["rust-analyzer team"]

Diff for: Cargo.toml

@@ -19,7 +19,6 @@ dashmap.workspace = true
 hashbrown.workspace = true
 rustc-hash.workspace = true
 triomphe.workspace = true
-sptr = "0.3.2"
 
 [lints]
 workspace = true

Diff for: crates/intern/Cargo.toml

@@ -13,7 +13,6 @@ use std::{
 use dashmap::{DashMap, SharedValue};
 use hashbrown::{hash_map::RawEntryMut, HashMap};
 use rustc_hash::FxHasher;
-use sptr::Strict;
 use triomphe::Arc;
 
 pub mod symbols;
@@ -84,7 +83,7 @@ impl TaggedArcPtr {
     #[inline]
     pub(crate) unsafe fn try_as_arc_owned(self) -> Option<ManuallyDrop<Arc<Box<str>>>> {
         // Unpack the tag from the alignment niche
-        let tag = Strict::addr(self.packed.as_ptr()) & Self::BOOL_BITS;
+        let tag = self.packed.as_ptr().addr() & Self::BOOL_BITS;
         if tag != 0 {
             // Safety: We checked that the tag is non-zero -> true, so we are pointing to the data offset of an `Arc`
             Some(ManuallyDrop::new(unsafe {
@@ -99,40 +98,18 @@ impl TaggedArcPtr {
     fn pack_arc(ptr: NonNull<*const str>) -> NonNull<*const str> {
         let packed_tag = true as usize;
 
-        // can't use this strict provenance stuff here due to trait methods not being const
-        // unsafe {
-        //     // Safety: The pointer is derived from a non-null
-        //     NonNull::new_unchecked(Strict::map_addr(ptr.as_ptr(), |addr| {
-        //         // Safety:
-        //         // - The pointer is `NonNull` => it's address is `NonZero<usize>`
-        //         // - `P::BITS` least significant bits are always zero (`Pointer` contract)
-        //         // - `T::BITS <= P::BITS` (from `Self::ASSERTION`)
-        //         //
-        //         // Thus `addr >> T::BITS` is guaranteed to be non-zero.
-        //         //
-        //         // `{non_zero} | packed_tag` can't make the value zero.
-
-        //         (addr >> Self::BOOL_BITS) | packed_tag
-        //     }))
-        // }
-        // so what follows is roughly what the above looks like but inlined
-
-        let self_addr = ptr.as_ptr() as *const *const str as usize;
-        let addr = self_addr | packed_tag;
-        let dest_addr = addr as isize;
-        let offset = dest_addr.wrapping_sub(self_addr as isize);
-
-        // SAFETY: The resulting pointer is guaranteed to be NonNull as we only modify the niche bytes
-        unsafe { NonNull::new_unchecked(ptr.as_ptr().cast::<u8>().wrapping_offset(offset).cast()) }
+        unsafe {
+            // Safety: The pointer is derived from a non-null and bit-oring it with true (1) will
+            // not make it null.
+            NonNull::new_unchecked(ptr.as_ptr().map_addr(|addr| addr | packed_tag))
+        }
     }
 
     #[inline]
     pub(crate) fn pointer(self) -> NonNull<*const str> {
         // SAFETY: The resulting pointer is guaranteed to be NonNull as we only modify the niche bytes
         unsafe {
-            NonNull::new_unchecked(Strict::map_addr(self.packed.as_ptr(), |addr| {
-                addr & !Self::BOOL_BITS
-            }))
+            NonNull::new_unchecked(self.packed.as_ptr().map_addr(|addr| addr & !Self::BOOL_BITS))
         }
     }