Minor tweaks to Choice API

mkeeter · Feb 19, 2024 · af00ec5 · af00ec5
1 parent fe403f9
commit af00ec5
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Showing 3 changed files with 29 additions and 7 deletions.
diff --git a/fidget/src/core/compiler/op.rs b/fidget/src/core/compiler/op.rs
@@ -130,10 +130,8 @@ impl SsaOp {
             | SsaOp::MaxRegReg(out, ..) => *out,
         }
     }
-    /// Returns the number of choices made by the given opcode
-    ///
-    /// This is always zero or one.
-    pub fn choice_count(&self) -> usize {
+    /// Returns true if the given opcode is associated with a choice
+    pub fn has_choice(&self) -> bool {
         match self {
             SsaOp::Input(..)
             | SsaOp::Var(..)
@@ -153,11 +151,11 @@ impl SsaOp {
             | SsaOp::SubRegReg(..)
             | SsaOp::DivRegReg(..)
             | SsaOp::DivRegImm(..)
-            | SsaOp::DivImmReg(..) => 0,
+            | SsaOp::DivImmReg(..) => false,
             SsaOp::MinRegImm(..)
             | SsaOp::MaxRegImm(..)
             | SsaOp::MinRegReg(..)
-            | SsaOp::MaxRegReg(..) => 1,
+            | SsaOp::MaxRegReg(..) => true,
         }
     }
 }

diff --git a/fidget/src/core/vm/choice.rs b/fidget/src/core/vm/choice.rs
@@ -39,3 +39,27 @@ impl std::ops::BitOrAssign<Choice> for Choice {
         }
     }
 }
+
+impl std::ops::Not for Choice {
+    type Output = Choice;
+    fn not(self) -> Self {
+        match self {
+            Self::Unknown => Self::Both,
+            Self::Left => Self::Right,
+            Self::Right => Self::Left,
+            Self::Both => Self::Unknown,
+        }
+    }
+}
+
+impl std::ops::BitAndAssign<Choice> for Choice {
+    fn bitand_assign(&mut self, other: Self) {
+        *self = match (*self as u8) | ((!other as u8) & 0b11) {
+            0 => Self::Unknown,
+            1 => Self::Left,
+            2 => Self::Right,
+            3 => Self::Both,
+            _ => unreachable!(),
+        }
+    }
+}
diff --git a/fidget/src/core/vm/data.rs b/fidget/src/core/vm/data.rs
@@ -133,7 +133,7 @@ impl<const N: u8> VmData<N> {
             let index = op.output();
 
             if workspace.active(index).is_none() {
-                for _ in 0..op.choice_count() {
+                if op.has_choice() {
                     choice_iter.next().unwrap();
                 }
                 continue;