PregSet machine env

src/ion/reg_traversal.rs

@@ -52,13 +52,13 @@ impl<'a> RegTraversalIter<'a> {
         }
         let hints = [hint_reg, hint2_reg];
         let class = class as u8 as usize;
-        let offset_pref = if env.preferred_regs_by_class[class].n_regs() > 0 {
-            offset % env.preferred_regs_by_class[class].n_regs()
+        let offset_pref = if env.preferred_regs_by_class[class].len() > 0 {
+            offset % env.preferred_regs_by_class[class].len()
         } else {
             0
         };
-        let offset_non_pref = if env.non_preferred_regs_by_class[class].n_regs() > 0 {
-            offset % env.non_preferred_regs_by_class[class].n_regs()
+        let offset_non_pref = if env.non_preferred_regs_by_class[class].len() > 0 {
+            offset % env.non_preferred_regs_by_class[class].len()
         } else {
             0
         };
@@ -100,7 +100,7 @@ impl<'a> core::iter::Iterator for RegTraversalIter<'a> {
             return h;
         }
 
-        let n_pref_regs = self.env.preferred_regs_by_class[self.class].n_regs();
+        let n_pref_regs = self.env.preferred_regs_by_class[self.class].len();
         while self.pref_idx < n_pref_regs {
             let mut arr = self.env.preferred_regs_by_class[self.class].into_iter();
             let r = arr.nth(wrap(self.pref_idx + self.offset_pref, n_pref_regs));
@@ -111,8 +111,8 @@ impl<'a> core::iter::Iterator for RegTraversalIter<'a> {
             return r;
         }
 
-        let n_non_pref_regs = self.env.non_preferred_regs_by_class[self.class].n_regs();
-        while self.non_pref_idx < self.env.non_preferred_regs_by_class[self.class].n_regs() {
+        let n_non_pref_regs = self.env.non_preferred_regs_by_class[self.class].len();
+        while self.non_pref_idx < self.env.non_preferred_regs_by_class[self.class].len() {
             let mut arr = self.env.non_preferred_regs_by_class[self.class].into_iter();
             let r = arr.nth(wrap(
                 self.non_pref_idx + self.offset_non_pref,

src/lib.rs

@@ -241,25 +241,13 @@ impl PRegSet {
         self.bits[1] |= other.bits[1];
     }
 
-    /// Get the number of registers in the set
-    pub fn n_regs(&self) -> usize {
-        self.bits[0].count_ones() as usize + self.bits[1].count_ones() as usize
-    }
+    // Get the number of registers in the set
+    // pub fn n_regs(&self) -> usize {
+    //     (self.bits[0].count_ones() + self.bits[1].count_ones()) as usize
+    // }
 }
 
-impl IntoIterator for PRegSet {
-    type Item = PReg;
-    type IntoIter = PRegSetIter;
-    fn into_iter(self) -> PRegSetIter {
-        PRegSetIter { bits: self.bits }
-    }
-}
-
-pub struct PRegSetIter {
-    bits: [u128; 2],
-}
-
-impl Iterator for PRegSetIter {
+impl Iterator for PRegSet {
     type Item = PReg;
     fn next(&mut self) -> Option<PReg> {
         if self.bits[0] != 0 {
@@ -276,6 +264,12 @@ impl Iterator for PRegSetIter {
     }
 }
 
+impl ExactSizeIterator for PRegSet {
+    fn len(&self) -> usize {
+        (self.bits[0].count_ones() + self.bits[1].count_ones()) as usize
+    }
+}
+
 impl From<&MachineEnv> for PRegSet {
     fn from(env: &MachineEnv) -> Self {
         let mut res = Self::default();