Introduce Virtio-loopback epsilon release:

Epsilon release introduces a new compatibility layer which make virtio-loopback
design to work with QEMU and rust-vmm vhost-user backend without require any
changes.

Signed-off-by: Timos Ampelikiotis <t.ampelikiotis@virtualopensystems.com>
Change-Id: I52e57563e08a7d0bdc002f8e928ee61ba0c53dd9

1 files changed, 51 insertions, 0 deletions

diff --git a/target/riscv/bitmanip_helper.c b/target/riscv/bitmanip_helper.c
new file mode 100644
index 000000000..f1b5e5549
--- /dev/null
+++ b/target/riscv/bitmanip_helper.c
@@ -0,0 +1,51 @@
+/*
+ * RISC-V Bitmanip Extension Helpers for QEMU.
+ *
+ * Copyright (c) 2020 Kito Cheng, kito.cheng@sifive.com
+ * Copyright (c) 2020 Frank Chang, frank.chang@sifive.com
+ * Copyright (c) 2021 Philipp Tomsich, philipp.tomsich@vrull.eu
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2 or later, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "qemu/osdep.h"
+#include "qemu/host-utils.h"
+#include "exec/exec-all.h"
+#include "exec/helper-proto.h"
+#include "tcg/tcg.h"
+
+target_ulong HELPER(clmul)(target_ulong rs1, target_ulong rs2)
+{
+    target_ulong result = 0;
+
+    for (int i = 0; i < TARGET_LONG_BITS; i++) {
+        if ((rs2 >> i) & 1) {
+            result ^= (rs1 << i);
+        }
+    }
+
+    return result;
+}
+
+target_ulong HELPER(clmulr)(target_ulong rs1, target_ulong rs2)
+{
+    target_ulong result = 0;
+
+    for (int i = 0; i < TARGET_LONG_BITS; i++) {
+        if ((rs2 >> i) & 1) {
+            result ^= (rs1 >> (TARGET_LONG_BITS - i - 1));
+        }
+    }
+
+    return result;
+}