Commit 787190e3f4 for qemu.org

commit 787190e3f433022d6fd2983f5e5efdb848439a41
Author: Richard Henderson <richard.henderson@linaro.org>
Date:   Tue Dec 10 08:39:56 2024 -0600

    tcg/optimize: Build and use o_bits in fold_xor

    Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
    Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

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. */