for i, p := range inst.Prefix {
			if p == PrefixPT || p == PrefixPN {
				inst.Prefix[i] |= PrefixImplicit
			}
		}
	}

	switch inst.Op {
	case AAA, AAS, CBW, CDQE, CLC, CLD, CLI, CLTS, CMC, CPUID, CQO, CWD, DAA, DAS,
		FDECSTP, FINCSTP, FNCLEX, FNINIT, FNOP, FWAIT, HLT,
		ICEBP, INSB, INSD, INSW, INT, INTO, INVD, IRET, IRETQ,
		LAHF, LEAVE, LRET, MONITOR, MWAIT, NOP, OUTSB, OUTSD, OUTSW,

	"CMPSL",
	"CMPSQ",
	"CMPSS",
	"CMPSW",
	"CMPW",
	"CMPXCHG16B",
	"CMPXCHG8B",
	"CMPXCHGB",
	"CMPXCHGL",
	"CMPXCHGQ",
	"CMPXCHGW",
	"COMISD",
	"COMISS",
	"CPUID",
	"CQO",
	"CRC32B",
	"CRC32L",
	"CRC32Q",
	"CRC32W",
	"CVTPD2PL",
	"CVTPD2PS",
	"CVTPL2PD",
	"CVTPL2PS",
	"CVTPS2PD",
	"CVTPS2PL",
	"CVTSD2SL",
	"CVTSD2SQ",
	"CVTSD2SS",
	"CVTSL2SD",

00000350  cc e9 0f ea e8 03 99 49  4e c4 2c 43 36 54 b9 61  |.......IN.,C6T.a|
00000360  af d1 56 00 9a e4 f2 c2  6d cf e9 25 32 f5 34 b6  |..V.....m..%2.4.|
00000370  08 45 0f 43 71 6f 88 3f  7a 07 68 0b 91 fd 15 c3  |.E.Cqo.?z.h.....|
00000380  43 8a 9d c3 bf f9 56 3c  3d 07 62 d0 94 11 14 95  |C.....V<=.b.....|
00000390  63 27 28 d2 94 07 ff 1f  2b 99 76 a8 03 b4 8b 8f  |c'(.....+.v.....|

	TR6:  "%tr6",
	TR7:  "%tr7",
}

var gnuOp = map[Op]string{
	CBW:       "cbtw",
	CDQ:       "cltd",
	CMPSD:     "cmpsl",
	CMPSD_XMM: "cmpsd",
	CWD:       "cwtd",
	CWDE:      "cwtl",
	CQO:       "cqto",
	INSD:      "insl",
	IRET:      "iretw",
	IRETD:     "iret",
	IRETQ:     "iretq",
	LODSB:     "lods",
	LODSD:     "lods",
	LODSQ:     "lods",
	LODSW:     "lods",
	MOVSD:     "movsl",

	CMPXCHG:         "CMPXCHG",
	CMPXCHG16B:      "CMPXCHG16B",
	CMPXCHG8B:       "CMPXCHG8B",
	COMISD:          "COMISD",
	COMISS:          "COMISS",
	CPUID:           "CPUID",
	CQO:             "CQO",
	CRC32:           "CRC32",
	CVTDQ2PD:        "CVTDQ2PD",
	CVTDQ2PS:        "CVTDQ2PS",
	CVTPD2DQ:        "CVTPD2DQ",
	CVTPD2PI:        "CVTPD2PI",
	CVTPD2PS:        "CVTPD2PS",

	COMISS (R11), X11                       // 450f2f1b
	COMISS X2, X11                          // 440f2fda
	COMISS X11, X11                         // 450f2fdb
	CPUID                                   // 0fa2
	CQO                                     // 4899
	CRC32W (BX), DX                         // 66f20f38f113
	CRC32W (R11), DX                        // 66f2410f38f113
	CRC32W DX, DX                           // 66f20f38f1d2