Cleanup and speedup BDD handling

Author: Coloquinte

src/bdd.rs

@@ -41,7 +41,7 @@ fn level_complexity(table: &[u64], level: usize) -> usize {
     });
 
     // Sort-uniquify
-    luts.sort();
+    luts.sort_unstable();
     luts.dedup();
     luts.len()
 }
@@ -84,12 +84,12 @@ fn large_level_complexity(table: &[u64], level: usize) -> usize {
     });
 
     // Sort-uniquify
-    luts.sort();
+    luts.sort_unstable();
     luts.dedup();
     luts.len()
 }
 
-pub fn table_complexity(num_vars: usize, table: &[u64]) -> usize {
+pub fn table_bdd_complexity(num_vars: usize, table: &[u64]) -> usize {
     let mut complexity: usize = 0;
     for level in 1..std::cmp::min(num_vars, 6) {
         complexity += level_complexity(table, level);

src/lut.rs

@@ -406,7 +406,7 @@ impl Lut {
 
     /// Compute the number of nodes in the BDD representing these functions
     ///
-    /// Equivalent functions (up to output complementation) are represented by the same BDD node.
+    /// Equivalent functions (up to output complementation) are represented by a single BDD node.
     /// The natural variable order (0 to num_vars) is used: smaller BDDs may be possible with another ordering.
     pub fn bdd_complexity(luts: &[Self]) -> usize {
         if luts.is_empty() {
@@ -421,7 +421,7 @@ impl Lut {
         for l in luts {
             table.extend(l.blocks().iter());
         }
-        table_complexity(num_vars, table.as_slice())
+        table_bdd_complexity(num_vars, table.as_slice())
     }
 
     /// Return the hexadecimal string representing the function

src/static_lut.rs

@@ -407,7 +407,7 @@ impl<const NUM_VARS: usize, const NUM_WORDS: usize> StaticLut<NUM_VARS, NUM_WORD
         for l in luts {
             table.extend(l.blocks().iter());
         }
-        table_complexity(NUM_VARS, table.as_slice())
+        table_bdd_complexity(NUM_VARS, table.as_slice())
     }
 
     /// Return the hexadecimal string representing the function