From fdb324686ae09be81bfaa62a762825b5808a9663 Mon Sep 17 00:00:00 2001
From: Franco Colmenarez <info@francoacg.com>
Date: Sat, 26 Nov 2022 22:02:08 -0500
Subject: [PATCH] alu XOR

---
 snes-core/src/utils/alu.rs       | 30 ++++++++++++++++++++++++++++++
 snes-core/src/utils/num_trait.rs |  5 +++++
 2 files changed, 35 insertions(+)

diff --git a/snes-core/src/utils/alu.rs b/snes-core/src/utils/alu.rs
index a761210..4ecd2b4 100644
--- a/snes-core/src/utils/alu.rs
+++ b/snes-core/src/utils/alu.rs
@@ -109,6 +109,15 @@ pub fn asl<T: SnesNum>(target: T) -> (T, [Flags; 3]) {
     ])
 }
 
+pub fn xor<T: SnesNum>(target: T, value: T) -> (T, [Flags; 2]) {
+    let result = target.xor(value);
+    (result, [
+        Negative(result.is_negative()),
+        Zero(result.is_zero()),
+    ])
+}
+
+
 #[cfg(test)]
 mod alu_tests {
     use super::*;
@@ -315,4 +324,25 @@ mod alu_tests {
         assert_eq!(result, 0b00000000_00000000);
         assert_eq!(affected_flags, [Negative(false), Zero(true), Carry(true)]);
     }
+
+    #[test]
+    fn test_xor() {
+        // 8 bit
+        let (result, affected_flags) = xor(0b0101_0101_u8, 0b0101_0101_u8);
+        assert_eq!(result, 0);
+        assert_eq!(affected_flags, [Negative(false), Zero(true)]);
+
+        let (result, affected_flags) = xor(0b1000_0000_u8, 0b0000_0000_u8);
+        assert_eq!(result, 0b1000_0000);
+        assert_eq!(affected_flags, [Negative(true), Zero(false)]);
+
+        // 16 bit
+        let (result, affected_flags) = xor(0b01010101_00000000_u16, 0b01010101_00000000_u16);
+        assert_eq!(result, 0);
+        assert_eq!(affected_flags, [Negative(false), Zero(true)]);
+
+        let (result, affected_flags) = xor(0b10000000_00000000_u16, 0b00000000_00000000_u16);
+        assert_eq!(result, 0b10000000_00000000);
+        assert_eq!(affected_flags, [Negative(true), Zero(false)]);
+    }
 }
diff --git a/snes-core/src/utils/num_trait.rs b/snes-core/src/utils/num_trait.rs
index 6e5c05e..f8dfa51 100644
--- a/snes-core/src/utils/num_trait.rs
+++ b/snes-core/src/utils/num_trait.rs
@@ -6,6 +6,7 @@ pub trait SnesNum: Copy + Clone + Sized + Eq + PartialEq {
     fn sbc_snes(&self, v: Self, carry: bool) -> Self;
     fn and(&self, v: Self) -> Self;
     fn asl(&self) -> Self;
+    fn xor(&self, v: Self) -> Self;
     fn is_negative(&self) -> bool;
     fn is_zero(&self) -> bool;
     fn next_to_highest_bit(&self) -> bool;
@@ -67,6 +68,10 @@ macro_rules! define_impl {
                 (* self) << 1
             }
 
+            fn xor(&self, v: $t) -> $t {
+                (* self) ^ v
+            }
+
             fn is_negative(&self) -> bool {
                 (*self) & !(<$t>::MAX >> 1) != 0
             }