rust: small updates (#1560)

rust/Cargo.toml

@@ -1,5 +1,5 @@
 [workspace]
-
+resolver = "2"
 members = [
     "nextpnr",
     "example_printnets",

rust/nextpnr/Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 name = "nextpnr"
 version = "0.1.0"
-edition = "2021"
+edition = "2024"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 

rust/nextpnr/src/lib.rs

@@ -21,6 +21,7 @@ pub struct CellInfo {
 }
 
 impl CellInfo {
+    #[must_use]
     pub fn location(&self) -> Loc {
         unsafe { npnr_cellinfo_get_location(self) }
     }
@@ -36,10 +37,12 @@ impl NetInfo {
         unsafe { npnr_netinfo_driver(self) }
     }
 
+    #[must_use]
     pub fn is_global(&self) -> bool {
         unsafe { npnr_netinfo_is_global(self) }
     }
 
+    #[must_use]
     pub fn index(&self) -> NetIndex {
         unsafe { npnr_netinfo_udata(self) }
     }
@@ -50,6 +53,7 @@ impl NetInfo {
 pub struct NetIndex(i32);
 
 impl NetIndex {
+    #[must_use]
     pub fn into_inner(self) -> i32 {
         self.0
     }
@@ -61,6 +65,7 @@ pub struct PortRef {
 }
 
 impl PortRef {
+    #[must_use]
     pub fn cell(&self) -> Option<&CellInfo> {
         // SAFETY: handing out &s is safe when we have &self.
         unsafe { npnr_portref_cell(self) }
@@ -76,14 +81,21 @@ pub struct IdString(libc::c_int);
 #[repr(transparent)]
 pub struct BelId(u64);
 
+impl Default for BelId {
+    fn default() -> Self {
+        Self::null()
+    }
+}
+
 impl BelId {
     /// Return a sentinel value that represents an invalid bel.
+    #[must_use]
     pub fn null() -> Self {
-        // SAFETY: BelId() has no safety requirements.
-        unsafe { npnr_belid_null() }
+        npnr_belid_null()
     }
 
     /// Check if this bel is invalid.
+    #[must_use]
     pub fn is_null(self) -> bool {
         self == Self::null()
     }
@@ -93,9 +105,16 @@ impl BelId {
 #[repr(transparent)]
 pub struct PipId(u64);
 
+impl Default for PipId {
+    fn default() -> Self {
+        Self::null()
+    }
+}
+
 impl PipId {
+    #[must_use]
     pub fn null() -> Self {
-        unsafe { npnr_pipid_null() }
+        npnr_pipid_null()
     }
 }
 
@@ -103,14 +122,22 @@ impl PipId {
 #[repr(transparent)]
 pub struct WireId(u64);
 
+impl Default for WireId {
+    fn default() -> Self {
+        Self::null()
+    }
+}
+
 impl WireId {
     /// Return a sentinel value that represents an invalid wire.
+    #[must_use]
     pub fn null() -> Self {
         // SAFETY: WireId() has no safety requirements.
-        unsafe { npnr_wireid_null() }
+        npnr_wireid_null()
     }
 
     /// Check if this wire is invalid.
+    #[must_use]
     pub fn is_null(self) -> bool {
         self == Self::null()
     }
@@ -144,11 +171,13 @@ pub struct Context {
 
 impl Context {
     /// Get grid X dimension. All bels and pips must have X coordinates in the range `0 .. getGridDimX()-1` (inclusive).
+    #[must_use]
     pub fn grid_dim_x(&self) -> i32 {
         unsafe { npnr_context_get_grid_dim_x(self) }
     }
 
     /// Get grid Y dimension. All bels and pips must have Y coordinates in the range `0 .. getGridDimY()-1` (inclusive).
+    #[must_use]
     pub fn grid_dim_y(&self) -> i32 {
         unsafe { npnr_context_get_grid_dim_y(self) }
     }
@@ -166,11 +195,12 @@ impl Context {
     }
 
     /// Returns true if the bel is available. A bel can be unavailable because it is bound, or because it is exclusive to some other resource that is bound.
+    #[must_use]
     pub fn check_bel_avail(&self, bel: BelId) -> bool {
         unsafe { npnr_context_check_bel_avail(self, bel) }
     }
 
-    /// Bind a wire to a net. This method must be used when binding a wire that is driven by a bel pin. Use bindPip() when binding a wire that is driven by a pip.
+    /// Bind a wire to a net. This method must be used when binding a wire that is driven by a bel pin. Use `bindPip` when binding a wire that is driven by a pip.
     pub fn bind_wire(&mut self, wire: WireId, net: &mut NetInfo, strength: PlaceStrength) {
         let _lock = ARCH_MUTEX.lock().unwrap();
         unsafe { npnr_context_bind_wire(self, wire, net, strength) }
@@ -195,36 +225,44 @@ impl Context {
     }
 
     /// Get the source wire for a pip.
+    #[must_use]
     pub fn pip_src_wire(&self, pip: PipId) -> WireId {
         unsafe { npnr_context_get_pip_src_wire(self, pip) }
     }
 
     /// Get the destination wire for a pip.
+    #[must_use]
     pub fn pip_dst_wire(&self, pip: PipId) -> WireId {
         unsafe { npnr_context_get_pip_dst_wire(self, pip) }
     }
 
     // TODO: Should this be a Duration? Does that even make sense?
+    #[must_use]
     pub fn estimate_delay(&self, src: WireId, dst: WireId) -> f32 {
         unsafe { npnr_context_estimate_delay(self, src, dst) }
     }
 
+    #[must_use]
     pub fn pip_delay(&self, pip: PipId) -> f32 {
         unsafe { npnr_context_get_pip_delay(self, pip) }
     }
 
+    #[must_use]
     pub fn wire_delay(&self, wire: WireId) -> f32 {
         unsafe { npnr_context_get_wire_delay(self, wire) }
     }
 
+    #[must_use]
     pub fn delay_epsilon(&self) -> f32 {
         unsafe { npnr_context_delay_epsilon(self) }
     }
 
+    #[must_use]
     pub fn source_wire(&self, net: &NetInfo) -> WireId {
         unsafe { npnr_context_get_netinfo_source_wire(self, net) }
     }
 
+    #[must_use]
     pub fn sink_wires(&self, net: &NetInfo, sink: &PortRef) -> Vec<WireId> {
         let mut v = Vec::new();
         let mut n = 0;
@@ -239,41 +277,48 @@ impl Context {
         v
     }
 
-    pub fn bels(&self) -> BelIter {
+    #[must_use]
+    pub fn bels(&self) -> BelIter<'_> {
         let iter = unsafe { npnr_context_get_bels(self) };
         BelIter { iter, phantom_data: PhantomData }
     }
 
-    pub fn pips(&self) -> PipIter {
+    #[must_use]
+    pub fn pips(&self) -> PipIter<'_> {
         let iter = unsafe { npnr_context_get_pips(self) };
         PipIter { iter, phantom_data: PhantomData }
     }
 
-    pub fn wires(&self) -> WireIter {
+    #[must_use]
+    pub fn wires(&self) -> WireIter<'_> {
         let iter = unsafe { npnr_context_get_wires(self) };
         WireIter { iter, phantom_data: PhantomData }
     }
 
-    pub fn get_downhill_pips(&self, wire: WireId) -> DownhillPipsIter {
+    #[must_use]
+    pub fn get_downhill_pips(&self, wire: WireId) -> DownhillPipsIter<'_> {
         let iter = unsafe { npnr_context_get_pips_downhill(self, wire) };
         DownhillPipsIter {
             iter,
-            phantom_data: Default::default(),
+            phantom_data: PhantomData,
         }
     }
 
-    pub fn get_uphill_pips(&self, wire: WireId) -> UphillPipsIter {
+    #[must_use]
+    pub fn get_uphill_pips(&self, wire: WireId) -> UphillPipsIter<'_> {
         let iter = unsafe { npnr_context_get_pips_uphill(self, wire) };
         UphillPipsIter {
             iter,
-            phantom_data: Default::default(),
+            phantom_data: PhantomData,
         }
     }
 
+    #[must_use]
     pub fn pip_location(&self, pip: PipId) -> Loc {
         unsafe { npnr_context_get_pip_location(self, pip) }
     }
 
+    #[must_use]
     pub fn pip_direction(&self, pip: PipId) -> Loc {
         let mut src = Loc{x: 0, y: 0, z: 0};
         let mut dst = Loc{x: 0, y: 0, z: 0};
@@ -305,6 +350,7 @@ impl Context {
         Loc{x: dst.x - src.x, y: dst.y - src.y, z: 0}
     }
 
+    #[must_use]
     pub fn pip_avail_for_net(&self, pip: PipId, net: &mut NetInfo) -> bool {
         unsafe { npnr_context_check_pip_avail_for_net(self, pip, net) }
     }
@@ -313,42 +359,48 @@ impl Context {
         unsafe { npnr_context_check(self) }
     }
 
+    #[must_use]
     pub fn debug(&self) -> bool {
         unsafe { npnr_context_debug(self) }
     }
 
+    #[must_use]
     pub fn id(&self, s: &str) -> IdString {
         let s = std::ffi::CString::new(s).unwrap();
         unsafe { npnr_context_id(self, s.as_ptr()) }
     }
 
+    #[must_use]
     pub fn name_of(&self, s: IdString) -> &CStr {
         let _lock = RINGBUFFER_MUTEX.lock().unwrap();
         unsafe { CStr::from_ptr(npnr_context_name_of(self, s)) }
     }
 
+    #[must_use]
     pub fn name_of_pip(&self, pip: PipId) -> &CStr {
         let _lock = RINGBUFFER_MUTEX.lock().unwrap();
         unsafe { CStr::from_ptr(npnr_context_name_of_pip(self, pip)) }
     }
 
+    #[must_use]
     pub fn name_of_wire(&self, wire: WireId) -> &CStr {
         let _lock = RINGBUFFER_MUTEX.lock().unwrap();
         unsafe { CStr::from_ptr(npnr_context_name_of_wire(self, wire)) }
     }
 
+    #[must_use]
     pub fn verbose(&self) -> bool {
         unsafe { npnr_context_verbose(self) }
     }
 }
 
-extern "C" {
+unsafe extern "C" {
     pub fn npnr_log_info(format: *const c_char);
     pub fn npnr_log_error(format: *const c_char);
 
-    fn npnr_belid_null() -> BelId;
-    fn npnr_wireid_null() -> WireId;
-    fn npnr_pipid_null() -> PipId;
+    safe fn npnr_belid_null() -> BelId;
+    safe fn npnr_wireid_null() -> WireId;
+    safe fn npnr_pipid_null() -> PipId;
 
     fn npnr_context_get_grid_dim_x(ctx: &Context) -> libc::c_int;
     fn npnr_context_get_grid_dim_y(ctx: &Context) -> libc::c_int;
@@ -461,14 +513,15 @@ impl<'a> Nets<'a> {
     /// Create a new store for the nets of a context.
     ///
     /// Note that this leaks memory created by nextpnr; the intention is this is called once.
-    pub fn new(ctx: &'a Context) -> Nets<'a> {
+    #[must_use]
+    pub fn new(ctx: &'a Context) -> Self {
         let mut names: *mut libc::c_int = std::ptr::null_mut();
         let mut nets_ptr: *mut *mut NetInfo = std::ptr::null_mut();
         let size = unsafe {
             npnr_context_nets_leak(
                 ctx,
-                &mut names as *mut *mut libc::c_int,
-                &mut nets_ptr as *mut *mut *mut NetInfo,
+                &raw mut names,
+                &raw mut nets_ptr,
             )
         };
         let mut nets = HashMap::new();
@@ -481,9 +534,9 @@ impl<'a> Nets<'a> {
             // SAFETY: net is not null because it's a &mut, and users is only written to.
             // Leaking memory is the most convenient FFI I could think of.
             let len =
-                unsafe { npnr_netinfo_users_leak(net, &mut users_ptr as *mut *mut *const PortRef) };
+                unsafe { npnr_netinfo_users_leak(net, &raw mut users_ptr) };
             let users_slice =
-                unsafe { slice::from_raw_parts(users_ptr as *mut &PortRef, len as usize) };
+                unsafe { slice::from_raw_parts(users_ptr.cast::<&PortRef>(), len as usize) };
             let index = index_to_net.len() as i32;
             index_to_net.push(name);
             unsafe {
@@ -502,27 +555,33 @@ impl<'a> Nets<'a> {
     }
 
     /// Find net users given a net's name.
+    #[must_use]
     pub fn users_by_name(&self, net: IdString) -> Option<&&[&PortRef]> {
         self.users.get(&net)
     }
 
     /// Return the number of nets in the store.
+    #[must_use]
     pub fn len(&self) -> usize {
         self.nets.len()
     }
 
+    #[must_use]
     pub fn is_empty(&self) -> bool {
         self.nets.len() == 0
     }
 
+    #[must_use]
     pub fn name_from_index(&self, index: NetIndex) -> IdString {
         self.index_to_net[index.0 as usize]
     }
 
+    #[must_use]
     pub fn net_from_index(&self, index: NetIndex) -> &NetInfo {
         self.nets.get(&self.name_from_index(index)).unwrap()
     }
 
+    #[must_use]
     pub fn to_vec(&self) -> Vec<(&IdString, &&mut NetInfo)> {
         let mut v = Vec::new();
         v.extend(self.nets.iter());