target-tilegx: Handle most bit manipulation instructions

The crc instructions are omitted from this set.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>

target-tilegx/helper.c

@@ -40,6 +40,16 @@ uint64_t helper_cnttz(uint64_t arg)
     return ctz64(arg);
 }
 
+uint64_t helper_pcnt(uint64_t arg)
+{
+    return ctpop64(arg);
+}
+
+uint64_t helper_revbits(uint64_t arg)
+{
+    return revbit64(arg);
+}
+
 /*
  * Functional Description
  *     uint64_t a = rf[SrcA];