Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 tcg/optimize.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/tcg/optimize.c b/tcg/optimize.c
index 795f1c900e..572d314578 100644
--- a/tcg/optimize.c
+++ b/tcg/optimize.c
@@ -3039,7 +3039,7 @@ static bool fold_tcg_st_memcopy(OptContext *ctx, TCGOp *op)
 
 static bool fold_xor(OptContext *ctx, TCGOp *op)
 {
-    uint64_t z_mask, s_mask;
+    uint64_t z_mask, o_mask, s_mask;
     TempOptInfo *t1, *t2;
 
     if (fold_const2_commutative(ctx, op) ||
@@ -3051,9 +3051,12 @@ static bool fold_xor(OptContext *ctx, TCGOp *op)
 
     t1 = arg_info(op->args[1]);
     t2 = arg_info(op->args[2]);
-    z_mask = t1->z_mask | t2->z_mask;
+
+    z_mask = (t1->z_mask | t2->z_mask) & ~(t1->o_mask & t2->o_mask);
+    o_mask = (t1->o_mask & ~t2->z_mask) | (t2->o_mask & ~t1->z_mask);
     s_mask = t1->s_mask & t2->s_mask;
-    return fold_masks_zs(ctx, op, z_mask, s_mask);
+
+    return fold_masks_zos(ctx, op, z_mask, o_mask, s_mask);
 }
 
 /* Propagate constants and copies, fold constant expressions. */
-- 
2.43.0

On 6/3/25 1:08 AM, Richard Henderson wrote:
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> ---
>   tcg/optimize.c | 9 ++++++---
>   1 file changed, 6 insertions(+), 3 deletions(-)

Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>