diff --git a/instrs.txt b/instrs.txt
index adbae90..45a3512 100644
--- a/instrs.txt
+++ b/instrs.txt
@@ -315,16 +315,16 @@ ff/6                  M     GP     -      -      -      PUSH DEF64
 0f00/3                M     GP16   -      -      -      LTR
 0f00/4                M     GP16   -      -      -      VERR
 0f00/5                M     GP16   -      -      -      VERW
-NFx.0f01/0m           M     MEMZ   -      -      -      SGDT
-NFx.0f01/1m           M     MEMZ   -      -      -      SIDT
-NFx.0f01/2m           M     MEMZ   -      -      -      LGDT
-NFx.0f01/3m           M     MEMZ   -      -      -      LIDT
-NFx.0f01/4m           M     GP16   -      -      -      SMSW
-NFx.0f01/4r           M     GP     -      -      -      SMSW
-NFx.0f01/6            M     GP16   -      -      -      LMSW
-NFx.0f01/7m           M     GP     -      -      -      INVLPG SIZE_8
-NFx.0f01c8            NP    -      -      -      -      MONITOR
-NFx.0f01c9            NP    -      -      -      -      MWAIT
+0f01/0m               M     MEMZ   -      -      -      SGDT
+0f01/1m               M     MEMZ   -      -      -      SIDT
+0f01/2m               M     MEMZ   -      -      -      LGDT
+0f01/3m               M     MEMZ   -      -      -      LIDT
+0f01/4m               M     GP16   -      -      -      SMSW
+0f01/4r               M     GP     -      -      -      SMSW
+0f01/6                M     GP16   -      -      -      LMSW
+0f01/7m               M     GP     -      -      -      INVLPG SIZE_8
+0f01c8                NP    -      -      -      -      MONITOR
+0f01c9                NP    -      -      -      -      MWAIT
 NP.0f01ca             NP    -      -      -      -      CLAC
 NP.0f01cb             NP    -      -      -      -      STAC
 NP.0f01cf             NP    -      -      -      -      ENCLS
@@ -333,16 +333,15 @@ NP.0f01d1             NP    -      -      -      -      XSETBV
 NP.0f01d5             NP    -      -      -      -      XEND
 NP.0f01d6             NP    -      -      -      -      XTEST
 NP.0f01d7             NP    -      -      -      -      ENCLU
-NFx.0f01f8            NP    -      -      -      -      SWAPGS ONLY64
-NFx.0f01f9            NP    -      -      -      -      RDTSCP
+0f01f8                NP    -      -      -      -      SWAPGS ONLY64
+0f01f9                NP    -      -      -      -      RDTSCP
 0f02                  RM    GP     GP16   -      -      LAR
 0f03                  RM    GP     GP16   -      -      LSL
 0f05                  NP    -      -      -      -      SYSCALL ONLY64
 0f06                  NP    -      -      -      -      CLTS
 0f07                  NP    -      -      -      -      SYSRET ONLY64
 0f08                  NP    -      -      -      -      INVD
-NFx.0f09              NP    -      -      -      -      WBINVD
-F2.0f09               NP    -      -      -      -      WBINVD
+*0f09                 NP    -      -      -      -      WBINVD
 0f0b                  NP    -      -      -      -      UD2
 0f0d/0m               M     MEM8   -      -      -      PREFETCH
 0f0d/1m               M     MEM8   -      -      -      PREFETCHW
@@ -456,11 +455,9 @@ F3.0fb8               RM    GP     GP     -      -      POPCNT USE66
 0fba/6                MI    GP     IMM8   -      -      BTR LOCK
 0fba/7                MI    GP     IMM8   -      -      BTC LOCK
 0fbb                  MR    GP     GP     -      -      BTC LOCK
-NFx.0fbc              RM    GP     GP     -      -      BSF
-F2.0fbc               RM    GP     GP     -      -      BSF USE66
+*0fbc                 RM    GP     GP     -      -      BSF
 F3.0fbc               RM    GP     GP     -      -      TZCNT USE66
-NFx.0fbd              RM    GP     GP     -      -      BSR
-F2.0fbd               RM    GP     GP     -      -      BSR USE66
+*0fbd                 RM    GP     GP     -      -      BSR
 F3.0fbd               RM    GP     GP     -      -      LZCNT USE66
 0fbe                  RM    GP     GP8    -      -      MOVSX ENC_SEPSZ
 0fbf                  RM    GP     GP16   -      -      MOVSX ENC_SEPSZ
diff --git a/parseinstrs.py b/parseinstrs.py
index 15b4c87..30d3b0d 100644
--- a/parseinstrs.py
+++ b/parseinstrs.py
@@ -440,7 +440,7 @@ def encode_table(entries):
     mnemonics = defaultdict(list)
     mnemonics["FE_NOP"].append(("NP", 0, 0, "0x90"))
     for weak, opcode, desc in entries:
-        if weak or "ONLY32" in desc.flags:
+        if "ONLY32" in desc.flags or desc.mnemonic[:9] == "RESERVED_":
             continue
 
         opsizes = {8} if "SIZE_8" in desc.flags else {16, 32, 64}
diff --git a/tests/test_decode.c b/tests/test_decode.c
index ded90f1..492d959 100644
--- a/tests/test_decode.c
+++ b/tests/test_decode.c
@@ -170,6 +170,20 @@ main(int argc, char** argv)
     // [reg+s*reg+disp32]
     TEST64("\x42\x01\x84\x25\x01\x00\x00\x00", "add dword ptr [rbp+1*r12+0x1], eax");
 
+    TEST("\x0f\xbc\xc0", "bsf eax, eax");
+    TEST("\x66\x0f\xbc\xc0", "bsf ax, ax");
+    TEST("\xf2\x0f\xbc\xc0", "bsf eax, eax");
+    TEST("\x66\xf2\x0f\xbc\xc0", "bsf ax, ax");
+    TEST("\xf3\x0f\xbc\xc0", "tzcnt eax, eax");
+    TEST("\x66\xf3\x0f\xbc\xc0", "tzcnt ax, ax");
+    TEST32("\x0f\x01\x00", "sgdt [eax]");
+    TEST64("\x0f\x01\x00", "sgdt [rax]");
+    TEST32("\x66\x0f\x01\x00", "sgdt [eax]");
+    TEST64("\x66\x0f\x01\x00", "sgdt [rax]");
+    TEST32("\xf2\x0f\x01\x00", "sgdt [eax]");
+    TEST64("\xf2\x0f\x01\x00", "sgdt [rax]");
+    TEST32("\xf3\x0f\x01\x00", "sgdt [eax]");
+    TEST64("\xf3\x0f\x01\x00", "sgdt [rax]");
     TEST("\x04\x01", "add al, 0x1");
     TEST("\x66\x68\xff\xad", "pushw 0xadff");
     TEST32("\x68\xff\xad\x90\xbc", "push 0xbc90adff");