target/riscv: rvk: add support for zbkx extension

 - add xperm4 and xperm8 instructions

Signed-off-by: Weiwei Li <liweiwei@iscas.ac.cn>
Signed-off-by: Junqiang Wang <wangjunqiang@iscas.ac.cn>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20220423023510.30794-5-liweiwei@iscas.ac.cn>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>

1 files changed, 27 insertions, 0 deletions

diff --git a/target/riscv/bitmanip_helper.c b/target/riscv/bitmanip_helper.c
index e003e8b25b..b99c4a39a1 100644
--- a/target/riscv/bitmanip_helper.c
+++ b/target/riscv/bitmanip_helper.c
@@ -102,3 +102,30 @@ target_ulong HELPER(zip)(target_ulong rs1)
     x = do_shuf_stage(x, shuf_masks[0], shuf_masks[0] >> 1, 1);
     return x;
 }
+
+static inline target_ulong do_xperm(target_ulong rs1, target_ulong rs2,
+                                    uint32_t sz_log2)
+{
+    target_ulong r = 0;
+    target_ulong sz = 1LL << sz_log2;
+    target_ulong mask = (1LL << sz) - 1;
+    target_ulong pos;
+
+    for (int i = 0; i < TARGET_LONG_BITS; i += sz) {
+        pos = ((rs2 >> i) & mask) << sz_log2;
+        if (pos < sizeof(target_ulong) * 8) {
+            r |= ((rs1 >> pos) & mask) << i;
+        }
+    }
+    return r;
+}
+
+target_ulong HELPER(xperm4)(target_ulong rs1, target_ulong rs2)
+{
+    return do_xperm(rs1, rs2, 2);
+}
+
+target_ulong HELPER(xperm8)(target_ulong rs1, target_ulong rs2)
+{
+    return do_xperm(rs1, rs2, 3);
+}