avoid some clones

Author: RalfJung

src/alloc/alloc_bytes.rs

@@ -90,15 +90,15 @@ impl MiriAllocBytes {
         size: u64,
         align: u64,
         params: MiriAllocParams,
-        alloc_fn: impl FnOnce(Layout) -> *mut u8,
+        alloc_fn: impl FnOnce(Layout, &MiriAllocParams) -> *mut u8,
     ) -> Result<MiriAllocBytes, ()> {
         let size = usize::try_from(size).map_err(|_| ())?;
         let align = usize::try_from(align).map_err(|_| ())?;
         let layout = Layout::from_size_align(size, align).map_err(|_| ())?;
         // When size is 0 we allocate 1 byte anyway, to ensure each allocation has a unique address.
         let alloc_layout =
             if size == 0 { Layout::from_size_align(1, align).unwrap() } else { layout };
-        let ptr = alloc_fn(alloc_layout);
+        let ptr = alloc_fn(alloc_layout, &params);
         if ptr.is_null() {
             Err(())
         } else {
@@ -119,12 +119,9 @@ impl AllocBytes for MiriAllocBytes {
         let slice = slice.into();
         let size = slice.len();
         let align = align.bytes();
-        // We need to clone here, since one copy goes into the alloc_fn and
-        // another is stored in the actual MiriAllocBytes
-        let p_clone = params.clone();
         // SAFETY: `alloc_fn` will only be used with `size != 0`.
-        let alloc_fn = |layout| unsafe {
-            match p_clone {
+        let alloc_fn = |layout, params: &MiriAllocParams| unsafe {
+            match params {
                 MiriAllocParams::Global => alloc::alloc(layout),
                 #[cfg(target_os = "linux")]
                 MiriAllocParams::Isolated(alloc) => alloc.borrow_mut().alloc(layout),
@@ -143,10 +140,9 @@ impl AllocBytes for MiriAllocBytes {
     fn zeroed(size: Size, align: Align, params: MiriAllocParams) -> Option<Self> {
         let size = size.bytes();
         let align = align.bytes();
-        let p_clone = params.clone();
         // SAFETY: `alloc_fn` will only be used with `size != 0`.
-        let alloc_fn = |layout| unsafe {
-            match p_clone {
+        let alloc_fn = |layout, params: &MiriAllocParams| unsafe {
+            match params {
                 MiriAllocParams::Global => alloc::alloc_zeroed(layout),
                 #[cfg(target_os = "linux")]
                 MiriAllocParams::Isolated(alloc) => alloc.borrow_mut().alloc_zeroed(layout),