diff --git a/rtl/x86_fpdbgdisas.pp b/rtl/x86_fpdbgdisas.pp
index c2f1c383..c5829a33 100644
--- a/rtl/x86_fpdbgdisas.pp
+++ b/rtl/x86_fpdbgdisas.pp
@@ -497,7 +497,7 @@ type
     procedure CheckRepeatX;
 
     procedure ClearSIMDPrefix;
-    procedure DecodeSIMD(AValidClear: TSimdOpcodes = [soNone, so66, soF2, soF3]; ASizeOK: Boolean = False);
+    procedure DecodeSIMD(AValidClear: TSimdOpcodes = [soNone, so66, soF2, soF3]; ASizeOK: Boolean = True);
     procedure DecodeModRM;
 
     procedure Do2ByteOpcode;
@@ -3597,7 +3597,7 @@ begin
       AddGv; AddEw;
     end;
     $B8: begin
-      DecodeSIMD([soNone, soF3], True);
+      DecodeSIMD([soNone, soF3]);
       case SimdOpcode of
         soNone: begin SetOpcode(OPjmpe  ); AddIz;        end;  // Itanium SDM, volume 4, page 256.
         soF3:   begin SetOpcode(OPpopcnt); AddGv; AddEv; end;
@@ -3614,7 +3614,7 @@ begin
       AddEv; AddGv;
     end;
     $BC: begin
-      DecodeSIMD([soNone, soF3], True);
+      DecodeSIMD([soNone, soF3]);
       case SimdOpcode of
         soNone,
         so66:   begin SetOpcode(OPbsf  ); AddGv; AddEv; end;
@@ -3622,7 +3622,7 @@ begin
       end;
     end;
     $BD: begin
-      DecodeSIMD([soNone, soF3], True);
+      DecodeSIMD([soNone, soF3]);
       case SimdOpcode of
         soNone,
         so66:   begin SetOpcode(OPbsr  ); AddGv; AddEv; end;