diff --git a/src/state.rs b/src/state.rs
index da97e84..c469081 100644
--- a/src/state.rs
+++ b/src/state.rs
@@ -70,13 +70,15 @@ impl Value for u32 {
 #[derive(Debug, Clone, Copy)]
 pub struct WaveValue {
     pub value: u32,
+    pub warp_size: usize,
     pub default_lane: Option<usize>,
     pub mutations: Option<[bool; 32]>,
 }
 impl WaveValue {
-    pub fn new(value: u32) -> Self {
+    pub fn new(value: u32, warp_size: usize) -> Self {
         Self {
             value,
+            warp_size,
             default_lane: None,
             mutations: None,
         }
@@ -92,7 +94,7 @@ impl WaveValue {
     }
     pub fn apply_muts(&mut self) {
         self.value = 0;
-        for lane in 0..32 {
+        for lane in 0..self.warp_size {
             if self.mutations.unwrap()[lane] {
                 self.value |= 1 << lane;
             }
@@ -106,16 +108,40 @@ mod test_state {
 
     #[test]
     fn test_wave_value() {
-        let mut val = WaveValue::new(0b11000000000000011111111111101110);
+        let mut val = WaveValue::new(0b11000000000000011111111111101110, 32);
         val.default_lane = Some(0);
         assert!(!val.read());
         val.default_lane = Some(31);
         assert!(val.read());
     }
 
+    #[test]
+    fn test_wave_value_small() {
+        let mut val = WaveValue::new(0, 1);
+        val.default_lane = Some(0);
+        assert!(!val.read());
+        assert_eq!(val.value, 0);
+        val.set_lane(true);
+        val.apply_muts();
+        assert!(val.read());
+        assert_eq!(val.value, 1);
+    }
+
+    #[test]
+    fn test_wave_value_small_alt() {
+        let mut val = WaveValue::new(0, 2);
+        val.default_lane = Some(0);
+        assert!(!val.read());
+        assert_eq!(val.value, 0);
+        val.set_lane(true);
+        val.apply_muts();
+        assert!(val.read());
+        assert_eq!(val.value, 1);
+    }
+
     #[test]
     fn test_wave_value_mutations() {
-        let mut val = WaveValue::new(0b10001);
+        let mut val = WaveValue::new(0b10001, 32);
         val.default_lane = Some(0);
         val.set_lane(false);
         assert!(val.mutations.unwrap().iter().all(|x| !x));
diff --git a/src/thread.rs b/src/thread.rs
index 68b09d3..2097eb0 100644
--- a/src/thread.rs
+++ b/src/thread.rs
@@ -28,6 +28,7 @@ pub struct Thread<'a> {
     pub stream: Vec<u32>,
     pub simm: Option<u32>,
     pub sgpr_co: &'a mut Option<(usize, WaveValue)>,
+    pub warp_size: usize,
     pub scalar: bool,
 }
 
@@ -992,7 +993,7 @@ impl<'a> Thread<'a> {
                     let sdst = ((instr >> 8) & 0x7f) as usize;
                     let f = |i: u32| -> usize { ((instr >> i) & 0x1ff) as usize };
                     let (s0, s1, s2) = (f(32), f(41), f(50));
-                    let mut carry_in = WaveValue::new(self.val(s2));
+                    let mut carry_in = WaveValue::new(self.val(s2), self.warp_size);
                     carry_in.default_lane = self.vcc.default_lane;
                     let omod = (instr >> 59) & 0x3;
                     let _neg = (instr >> 61) & 0x7;
@@ -1352,7 +1353,8 @@ impl<'a> Thread<'a> {
                                         796 => s0 * 2f32.powi(s1.to_bits() as i32),
                                         // cnd_mask isn't a float only ALU but supports neg
                                         257 => {
-                                            let mut cond = WaveValue::new(s2.to_bits());
+                                            let mut cond =
+                                                WaveValue::new(s2.to_bits(), self.warp_size);
                                             cond.default_lane = self.vcc.default_lane;
                                             match cond.read() {
                                                 true => s1,
@@ -1795,7 +1797,7 @@ impl<'a> Thread<'a> {
         let mut wv = self
             .sgpr_co
             .map(|(_, wv)| wv)
-            .unwrap_or_else(|| WaveValue::new(0));
+            .unwrap_or_else(|| WaveValue::new(0, self.warp_size));
         wv.default_lane = self.vcc.default_lane;
         wv.set_lane(val);
         *self.sgpr_co = Some((idx, wv));
@@ -3777,8 +3779,8 @@ fn _helper_test_thread() -> Thread<'static> {
     let static_sgpr: &'static mut Vec<u32> = Box::leak(Box::new(vec![0; 256]));
     let static_vgpr: &'static mut VGPR = Box::leak(Box::new(VGPR::new()));
     let static_scc: &'static mut u32 = Box::leak(Box::new(0));
-    let static_exec: &'static mut WaveValue = Box::leak(Box::new(WaveValue::new(u32::MAX)));
-    let static_vcc: &'static mut WaveValue = Box::leak(Box::new(WaveValue::new(0)));
+    let static_exec: &'static mut WaveValue = Box::leak(Box::new(WaveValue::new(u32::MAX, 32)));
+    let static_vcc: &'static mut WaveValue = Box::leak(Box::new(WaveValue::new(0, 32)));
     let static_sds: &'static mut VecDataStore = Box::leak(Box::new(VecDataStore::new()));
     let static_co: &'static mut Option<(usize, WaveValue)> = Box::leak(Box::new(None));
 
@@ -3794,6 +3796,7 @@ fn _helper_test_thread() -> Thread<'static> {
         pc_offset: 0,
         stream: vec![],
         sgpr_co: static_co,
+        warp_size: 32,
         scalar: false,
     };
     thread.vec_reg.default_lane = Some(0);
diff --git a/src/work_group.rs b/src/work_group.rs
index ec2d075..3db488a 100644
--- a/src/work_group.rs
+++ b/src/work_group.rs
@@ -106,7 +106,11 @@ impl<'a> WorkGroup<'a> {
         };
         let (mut vec_reg, mut vcc, mut exec) = match wave_state {
             Some(val) => (val.2.clone(), val.3.clone(), val.4.clone()),
-            _ => (VGPR::new(), WaveValue::new(0), WaveValue::new(u32::MAX)),
+            _ => (
+                VGPR::new(),
+                WaveValue::new(0, threads.len()),
+                WaveValue::new((1 << threads.len()) - 1, threads.len()),
+            ),
         };
 
         let mut seeded_lanes = vec![];
@@ -167,6 +171,7 @@ impl<'a> WorkGroup<'a> {
                     stream: self.kernel[pc..self.kernel.len()].to_vec(),
                     scalar: false,
                     simm: None,
+                    warp_size: threads.len(),
                     sgpr_co: &mut sgpr_co,
                 };
                 thread.interpret()?;