tcg/optimize: Fold eqv with immediate to xor

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

diff --git a/tcg/optimize.c b/tcg/optimize.c
index 9303bb5b64cd74ef2c45b6da76f851b7d1566c29..e18fe37ad26f5511e65da600963a8d7d8fffc7c0 100644 (file)
--- a/tcg/optimize.c
+++ b/tcg/optimize.c
@@ -1807,6 +1807,7 @@ static bool fold_dup2(OptContext *ctx, TCGOp *op)
 static bool fold_eqv(OptContext *ctx, TCGOp *op)
 {
     uint64_t s_mask;
+    TempOptInfo *t1, *t2;
 
     if (fold_const2_commutative(ctx, op) ||
         fold_xi_to_x(ctx, op, -1) ||
@@ -1814,8 +1815,28 @@ static bool fold_eqv(OptContext *ctx, TCGOp *op)
         return true;
     }
 
-    s_mask = arg_info(op->args[1])->s_mask
-           & arg_info(op->args[2])->s_mask;
+    t2 = arg_info(op->args[2]);
+    if (ti_is_const(t2)) {
+        /* Fold eqv r,x,i to xor r,x,~i. */
+        switch (ctx->type) {
+        case TCG_TYPE_I32:
+        case TCG_TYPE_I64:
+            op->opc = INDEX_op_xor;
+            break;
+        case TCG_TYPE_V64:
+        case TCG_TYPE_V128:
+        case TCG_TYPE_V256:
+            op->opc = INDEX_op_xor_vec;
+            break;
+        default:
+            g_assert_not_reached();
+        }
+        op->args[2] = arg_new_constant(ctx, ~ti_const_val(t2));
+        return fold_xor(ctx, op);
+    }
+
+    t1 = arg_info(op->args[1]);
+    s_mask = t1->s_mask & t2->s_mask;
     return fold_masks_s(ctx, op, s_mask);
 }