diff --git a/dynasm/dasm_x86.lua b/dynasm/dasm_x86.lua
index 4de5b478..5f82f4f3 100644
--- a/dynasm/dasm_x86.lua
+++ b/dynasm/dasm_x86.lua
@@ -1117,6 +1117,9 @@ local map_op = {
   fucompp_0 =	"DAE9",
   fcompp_0 =	"DED9",
 
+  fldenv_1 =	"x.:D94m",
+  fnstenv_1 =	"x.:D96m",
+  fstenv_1 =	"x.:9BD96m",
   fldcw_1 =	"xw:nD95m",
   fstcw_1 =	"xw:n9BD97m",
   fnstcw_1 =	"xw:nD97m",
@@ -1192,6 +1195,8 @@ local map_op = {
   cvttps2dq_2 =	"rmo:F30F5BrM",
   cvttsd2si_2 =	"rr/do:F20F2CrM|rr/qo:|rx/dq:|rxq:",
   cvttss2si_2 =	"rr/do:F30F2CrM|rr/qo:|rxd:|rx/qd:",
+  fxsave_1 =	"x.:0FAE0m",
+  fxrstor_1 =	"x.:0FAE1m",
   ldmxcsr_1 =	"xd:0FAE2m",
   lfence_0 =	"0FAEE8",
   maskmovdqu_2 = "rro:660FF7rM",