target/riscv: vmfirst find-first-set mask bit

Signed-off-by: LIU Zhiwei <zhiwei_liu@c-sky.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20200701152549.1218-52-zhiwei_liu@c-sky.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>

1 files changed, 19 insertions, 0 deletions

diff --git a/target/riscv/vector_helper.c b/target/riscv/vector_helper.c
index 63933060fc..e0ec02cda3 100644
--- a/target/riscv/vector_helper.c
+++ b/target/riscv/vector_helper.c
@@ -4562,3 +4562,22 @@ target_ulong HELPER(vmpopc_m)(void *v0, void *vs2, CPURISCVState *env,
     }
     return cnt;
 }
+
+/* vmfirst find-first-set mask bit*/
+target_ulong HELPER(vmfirst_m)(void *v0, void *vs2, CPURISCVState *env,
+                               uint32_t desc)
+{
+    uint32_t mlen = vext_mlen(desc);
+    uint32_t vm = vext_vm(desc);
+    uint32_t vl = env->vl;
+    int i;
+
+    for (i = 0; i < vl; i++) {
+        if (vm || vext_elem_mask(v0, mlen, i)) {
+            if (vext_elem_mask(vs2, mlen, i)) {
+                return i;
+            }
+        }
+    }
+    return -1LL;
+}