diff --git a/decode.c b/decode.c
index c84e9f6..a6bac57 100644
--- a/decode.c
+++ b/decode.c
@@ -506,7 +506,9 @@ prefix_end:
         uint8_t imm_size;
         if (imm_byte)
             imm_size = 1;
-        else if (UNLIKELY(instr->type == FDI_RET || instr->type == FDI_RETF))
+        else if (UNLIKELY(instr->type == FDI_RET || instr->type == FDI_RETF ||
+                          instr->type == FDI_SSE_EXTRQ ||
+                          instr->type == FDI_SSE_INSERTQ))
             imm_size = 2;
         else if (UNLIKELY(desc->type == FDI_JMPF || desc->type == FDI_CALLF))
             imm_size = op_size + 2;
diff --git a/format.c b/format.c
index b86ecec..f791dce 100644
--- a/format.c
+++ b/format.c
@@ -342,6 +342,11 @@ fd_format_abs(const FdInstr* instr, uint64_t addr, char* buffer, size_t len)
             switch (FD_TYPE(instr)) {
             default:
                 goto nosplitimm;
+            case FDI_SSE_EXTRQ:
+            case FDI_SSE_INSERTQ:
+                splitimm = immediate & 0xff;
+                immediate = (immediate >> 8) & 0xff;
+                break;
             case FDI_ENTER:
                 splitimm = immediate & 0xffff;
                 immediate = (immediate >> 16) & 0xff;
diff --git a/instrs.txt b/instrs.txt
index 14979ad..42f704a 100644
--- a/instrs.txt
+++ b/instrs.txt
@@ -352,6 +352,10 @@ F2.0f09               NP    -      -      -      -      WBINVD
 0f0d/5m               M     MEM8   -      -      -      RESERVED_PREFETCH
 0f0d/6m               M     MEM8   -      -      -      RESERVED_PREFETCH
 0f0d/7m               M     MEM8   -      -      -      RESERVED_PREFETCH
+0f0e                  NP    -      -      -      -      FEMMS ONLYAMD
+# TODO: actually decode 3DNow! instructions. Given that 3DNow! no longer exists,
+# this is unlikely to happen, though.
+0f0f                  RMI   MMX    MMX    IMM8   -      3DNOW ONLYAMD
 0f18/0m               M     MEM8   -      -      -      PREFETCHNTA
 0f18/1m               M     MEM8   -      -      -      PREFETCHT0
 0f18/2m               M     MEM8   -      -      -      PREFETCHT1
@@ -703,6 +707,11 @@ F2.0f70               RMI   XMM    XMM    IMM8   -      SSE_PSHUFLW
 66.0f74               RM    XMM    XMM    -      -      SSE_PCMPEQB
 66.0f75               RM    XMM    XMM    -      -      SSE_PCMPEQW
 66.0f76               RM    XMM    XMM    -      -      SSE_PCMPEQD
+# EXTRQ/INSERTQ immediate size handled in code.
+66.0f78/0r            MI    XMM    IMM16  -      -      SSE_EXTRQ ONLYAMD
+F2.0f78/r             RMI   XMM    XMM    IMM16  -      SSE_INSERTQ ONLYAMD
+66.0f79/r             RM    XMM    XMM    -      -      SSE_EXTRQ ONLYAMD
+F2.0f79/r             RM    XMM    XMM    -      -      SSE_INSERTQ ONLYAMD
 66.0f7c               RM    XMM    XMM    -      -      SSE_HADDPD
 F2.0f7c               RM    XMM    XMM    -      -      SSE_HADDPS
 66.0f7d               RM    XMM    XMM    -      -      SSE_HSUBPD
@@ -1456,6 +1465,27 @@ F3.0fc7/6m            M     MEM64  -      -      -      VMXON
 66.0f01ce             NP    -      -      -      -      SEAMOPS
 66.0f01cf             NP    -      -      -      -      SEAMCALL
 
+# AMD SVM
+NP.0f01d8             NP    -      -      -      -      VMRUN ONLYAMD
+NP.0f01d9             NP    -      -      -      -      VMMCALL ONLYAMD
+NP.0f01da             NP    -      -      -      -      VMLOAD ONLYAMD
+NP.0f01db             NP    -      -      -      -      VMSAVE ONLYAMD
+NP.0f01dc             NP    -      -      -      -      STGI ONLYAMD
+NP.0f01dd             NP    -      -      -      -      CLGI ONLYAMD
+NP.0f01de             NP    -      -      -      -      SKINIT ONLYAMD
+NP.0f01df             NP    -      -      -      -      INVLPGA ONLYAMD
+NP.0f01fa             NP    -      -      -      -      MONITORX ONLYAMD
+F3.0f01fa             NP    -      -      -      -      MCOMMIT ONLYAMD
+NP.0f01fb             NP    -      -      -      -      MWAITX ONLYAMD
+NP.0f01fe             NP    -      -      -      -      INVLPGB ONLYAMD
+NP.0f01ff             NP    -      -      -      -      TLBSYNC ONLYAMD
+
+# AMD SNP
+F3.0f01fe             NP    -      -      -      -      RMPADJUST ONLYAMD ONLY64
+F2.0f01fe             NP    -      -      -      -      RMPUPDATE ONLYAMD ONLY64
+F3.0f01ff             NP    -      -      -      -      PSMASH ONLYAMD ONLY64
+F2.0f01ff             NP    -      -      -      -      PVALIDATE ONLYAMD ONLY64
+
 # WAITPKG
 66.0fae/6r            M     GP32   -      -      -      TPAUSE
 F3.0fae/6r            M     GP     -      -      -      UMONITOR
diff --git a/tests/test_decode.c b/tests/test_decode.c
index f9badea..5db2dae 100644
--- a/tests/test_decode.c
+++ b/tests/test_decode.c
@@ -315,6 +315,8 @@ main(int argc, char** argv)
     TEST("\x66\x0f\x71\xd0\x01", "psrlw xmm0, 0x1");
     TEST("\x66\x0f\x3a\x20\xc4\x01", "pinsrb xmm0, spl, 0x1");
     TEST("\x66\x0f\x71\x10\x01", "UD");
+    TEST("\x66\x0f\x78\xc0\xab\xcd", "extrq xmm0, 0xab, 0xcd");
+    TEST("\xf2\x0f\x78\xc1\xab\xcd", "insertq xmm0, xmm1, 0xab, 0xcd");
 
     TEST32("\xc4\x00", "les eax, fword ptr [eax]");
     TEST32("\xc5\x00", "lds eax, fword ptr [eax]");