Directly use raw pointers in AtomicPtr store/load

Author: oli

compiler/rustc_codegen_ssa/src/mir/intrinsic.rs

@@ -437,7 +437,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                 match split[1] {
                     "cxchg" | "cxchgweak" => {
                         let ty = substs.type_at(0);
-                        if int_type_width_signed(ty, bx.tcx()).is_some() {
+                        if int_type_width_signed(ty, bx.tcx()).is_some() || ty.is_unsafe_ptr() {
                             let weak = split[1] == "cxchgweak";
                             let pair = bx.atomic_cmpxchg(
                                 args[0].immediate(),
@@ -464,7 +464,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
 
                     "load" => {
                         let ty = substs.type_at(0);
-                        if int_type_width_signed(ty, bx.tcx()).is_some() {
+                        if int_type_width_signed(ty, bx.tcx()).is_some() || ty.is_unsafe_ptr() {
                             let size = bx.layout_of(ty).size;
                             bx.atomic_load(args[0].immediate(), order, size)
                         } else {
@@ -474,7 +474,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
 
                     "store" => {
                         let ty = substs.type_at(0);
-                        if int_type_width_signed(ty, bx.tcx()).is_some() {
+                        if int_type_width_signed(ty, bx.tcx()).is_some() || ty.is_unsafe_ptr() {
                             let size = bx.layout_of(ty).size;
                             bx.atomic_store(args[1].immediate(), args[0].immediate(), order, size);
                             return;

library/core/src/sync/atomic.rs

@@ -966,8 +966,16 @@ impl<T> AtomicPtr<T> {
     #[inline]
     #[stable(feature = "rust1", since = "1.0.0")]
     pub fn load(&self, order: Ordering) -> *mut T {
+        #[cfg(not(bootstrap))]
         // SAFETY: data races are prevented by atomic intrinsics.
-        unsafe { atomic_load(self.p.get() as *mut usize, order) as *mut T }
+        unsafe {
+            atomic_load(self.p.get(), order)
+        }
+        #[cfg(bootstrap)]
+        // SAFETY: data races are prevented by atomic intrinsics.
+        unsafe {
+            atomic_load(self.p.get() as *mut usize, order) as *mut T
+        }
     }
 
     /// Stores a value into the pointer.
@@ -994,6 +1002,12 @@ impl<T> AtomicPtr<T> {
     #[inline]
     #[stable(feature = "rust1", since = "1.0.0")]
     pub fn store(&self, ptr: *mut T, order: Ordering) {
+        #[cfg(not(bootstrap))]
+        // SAFETY: data races are prevented by atomic intrinsics.
+        unsafe {
+            atomic_store(self.p.get(), ptr, order);
+        }
+        #[cfg(bootstrap)]
         // SAFETY: data races are prevented by atomic intrinsics.
         unsafe {
             atomic_store(self.p.get() as *mut usize, ptr as usize, order);
@@ -1105,6 +1119,7 @@ impl<T> AtomicPtr<T> {
         success: Ordering,
         failure: Ordering,
     ) -> Result<*mut T, *mut T> {
+        #[cfg(bootstrap)]
         // SAFETY: data races are prevented by atomic intrinsics.
         unsafe {
             let res = atomic_compare_exchange(
@@ -1119,6 +1134,11 @@ impl<T> AtomicPtr<T> {
                 Err(x) => Err(x as *mut T),
             }
         }
+        #[cfg(not(bootstrap))]
+        // SAFETY: data races are prevented by atomic intrinsics.
+        unsafe {
+            atomic_compare_exchange(self.p.get(), current, new, success, failure)
+        }
     }
 
     /// Stores a value into the pointer if the current value is the same as the `current` value.
@@ -1165,6 +1185,7 @@ impl<T> AtomicPtr<T> {
         success: Ordering,
         failure: Ordering,
     ) -> Result<*mut T, *mut T> {
+        #[cfg(bootstrap)]
         // SAFETY: data races are prevented by atomic intrinsics.
         unsafe {
             let res = atomic_compare_exchange_weak(
@@ -1179,6 +1200,11 @@ impl<T> AtomicPtr<T> {
                 Err(x) => Err(x as *mut T),
             }
         }
+        #[cfg(not(bootstrap))]
+        // SAFETY: data races are prevented by atomic intrinsics.
+        unsafe {
+            atomic_compare_exchange_weak(self.p.get(), current, new, success, failure)
+        }
     }
 
     /// Fetches the value, and applies a function to it that returns an optional