Commit 84b399df9a for qemu.org

commit 84b399df9abea985089d46fd94da559d83d0e085
Author: Richard Henderson <richard.henderson@linaro.org>
Date:   Mon Dec 9 21:35:53 2024 -0600

    tcg/optimize: Build and use one and affected bits in fold_or

    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 d22396f6d7..ce065d0e22 100644
--- a/tcg/optimize.c
+++ b/tcg/optimize.c
@@ -2263,7 +2263,7 @@ static bool fold_not(OptContext *ctx, TCGOp *op)

 static bool fold_or(OptContext *ctx, TCGOp *op)
 {
-    uint64_t z_mask, s_mask;
+    uint64_t z_mask, o_mask, s_mask, a_mask;
     TempOptInfo *t1, *t2;

     if (fold_const2_commutative(ctx, op) ||
@@ -2274,9 +2274,15 @@ static bool fold_or(OptContext *ctx, TCGOp *op)

     t1 = arg_info(op->args[1]);
     t2 = arg_info(op->args[2]);
+
     z_mask = t1->z_mask | t2->z_mask;
+    o_mask = t1->o_mask | t2->o_mask;
     s_mask = t1->s_mask & t2->s_mask;
-    return fold_masks_zs(ctx, op, z_mask, s_mask);
+
+    /* Affected bits are those not known one, masked by those known zero. */
+    a_mask = ~t1->o_mask & t2->z_mask;
+
+    return fold_masks_zosa(ctx, op, z_mask, o_mask, s_mask, a_mask);
 }

 static bool fold_orc(OptContext *ctx, TCGOp *op)