diff --git a/docs/vr-manual.xml b/docs/vr-manual.xml
index 5fd39d9..858e1c2 100644
--- a/docs/vr-manual.xml
+++ b/docs/vr-manual.xml
@@ -462,7 +462,14 @@ det2
                 Toggle instrumentation of vectorized instructions (number corresponds to the pack size)
             </para></listitem>
           </varlistentry>
+	  <varlistentry id="vr-opt.instr-unk" xreflabel="--vr-instr-unk">
+            <term><option><![CDATA[--vr-instr-unk=<yes|no> [default=yes]]]></option></term>
+            <listitem><para>
+                Toggle instrumentation of instructions with unknown vectorized status (fma is unvectorized in valgrind IR).
+            </para></listitem>
+          </varlistentry>
 
+	      
 	      <varlistentry id="vr-opt.instr-[flt|dbl]" xreflabel="--vr-instr-[flt|dbl]-">
             <term><option><![CDATA[--vr-instr-[flt|dbl]=<yes|no> [default=yes]]]></option></term>
             <listitem><para>
diff --git a/vr_clo.c b/vr_clo.c
index dc58c60..7c85fd6 100644
--- a/vr_clo.c
+++ b/vr_clo.c
@@ -302,6 +302,9 @@ Bool vr_process_clo (const HChar *arg) {
   else if (VG_BOOL_CLO (arg, "--vr-instr-vec8", bool_val)) {
      vr.instr_vec[VR_VEC_FULL8]= bool_val;
   }
+  else if (VG_BOOL_CLO (arg, "--vr-instr-unk", bool_val)) {
+     vr.instr_vec[VR_VEC_UNK]= bool_val;
+  }
 
   else if (VG_BOOL_CLO (arg, "--vr-instr-flt", bool_val)) {
      vr.instr_prec[VR_PREC_FLT]= bool_val;
diff --git a/vr_clo.txt b/vr_clo.txt
index a0d1983..21cff22 100644
--- a/vr_clo.txt
+++ b/vr_clo.txt
@@ -19,8 +19,8 @@
           This option can be activated with the env variable VERROU_BACKEND\n\
 \n\
     Perturbation of floating-point operations\n\
-      --rounding-mode=<random[|_det|_comdet|_scomdet]|average[|_det|_comdet|_scomdet]|prandom[|_det|_comdet]|sr_[s]monotonic|upward|downward|toward_zero|away_zero|farthest|float|ftz>\n\
-      [default=nearest]\n\
+      --rounding-mode=<random[|_det|_comdet|_scomdet]|average[|_det|_comdet|_scomdet]|prandom[|_det|_comdet]|sr_[s]monotonic|nearest|native|upward|downward|toward_zero|away_zero|farthest|float|ftz>\n\
+      [default=native]\n\
           Emulate the given rounding mode for operations instrumented with\n\
           the verrou backend. If this option is not provided, Verrou always\n\
           rounds to the nearest floating-point. Supported rounding modes are:\n\
@@ -158,6 +158,10 @@
       --vr-instr-vec<2,4,8>=<yes|no> [default=yes]\n\
           Toggle instrumentation of vectorized instructions (number\n\
           corresponds to the pack size)\n\
+\n\
+      --vr-instr-unk=<yes|no> [default=yes]\n\
+          Toggle instrumentation of instructions with unknown vectorized\n\
+          status (fma is unvectorized in valgrind IR).\n\
 \n\
       --vr-instr-[flt|dbl]=<yes|no> [default=yes]\n\
           Toggle instrumentation of float (or double) instructions.\n\