Merge pull request #2900 from o1-labs/dw/xor-tests

o1vm/riscv32im: add tests for XOR

o1vm/resources/programs/riscv32im/src/xor.S

@@ -0,0 +1,30 @@
+.section .text
+.globl _start
+
+_start:
+
+    # Simple XOR
+    li t0, 0b1100         # t0 = 0b1100
+    li t1, 0b1010         # t1 = 0b1010
+    xor t2, t0, t1        # t2 = t0 ^ t1 (Expected: t2 = 0b0110)
+
+    # XOR with zero (no change)
+    li t3, 0b1010         # t3 = 0b1010
+    li t4, 0              # t4 = 0
+    xor t5, t3, t4        # t5 = t3 ^ t4 (Expected: t5 = 0b1010)
+
+    # XOR of identical values (result 0)
+    li t6, 0b1111         # t6 = 0b1111
+    li t0, 0b1111         # t0 = 0b1111
+    xor t1, t6, t0        # t1 = t6 ^ t0 (Expected: t1 = 0)
+
+    # Custom exit syscall
+    li a0, 0
+    li a1, 0
+    li a2, 0
+    li a3, 0
+    li a4, 0
+    li a5, 0
+    li a6, 0
+    li a7, 42
+    ecall

o1vm/tests/test_riscv_elf.rs

@@ -302,3 +302,21 @@ fn test_sub_3() {
     assert_eq!(witness.registers[T1], 0);
     assert_eq!(witness.registers[T4], -2147483648_i32 as u32);
 }
+
+#[test]
+fn test_xor() {
+    let curr_dir = std::env::current_dir().unwrap();
+    let path = curr_dir.join(std::path::PathBuf::from(
+        "resources/programs/riscv32im/bin/xor",
+    ));
+    let state = o1vm::elf_loader::parse_riscv32(&path).unwrap();
+    let mut witness = Env::<Fp>::create(PAGE_SIZE.try_into().unwrap(), state);
+
+    while !witness.halt {
+        witness.step();
+    }
+
+    assert_eq!(witness.registers[T2], 0b0110); // Result: t2 = 0b0110
+    assert_eq!(witness.registers[T5], 0b1010); // Result: t5 = 0b1010
+    assert_eq!(witness.registers[T1], 0); // Result: t1 = 0
+}