// amd64/v3:`MOVBEQ`
	// s390x:`MOVD\s\(.*\),`
	// arm64:`REV`,`MOVD\s\(R[0-9]+\),`,-`MOV[BHW]`,-`REVW`,-`REV16W`
	// ppc64le:`MOVDBR`,-`MOV[BHW]Z`
	// ppc64:`MOVD`,-`MOV[BHW]Z`
	return binary.BigEndian.Uint64(b)
}

func load_be64_idx(b []byte, idx int) uint64 {
	// amd64/v1,amd64/v2:`BSWAPQ`,-`MOV[BWL]\t[^$]`,-`OR`
	// amd64/v3: `MOVBEQ\t\([A-Z]+[0-9]*\)\([A-Z]+[0-9]*\*1\), [A-Z]+[0-9]*`

		"pmovzxbw", "pmovzxbd", "pmovzxbq", "pmovzxwd", "pmovzxwq", "pmovzxdq",
		"pmovsxbw", "pmovsxbd", "pmovsxbq", "pmovsxwd", "pmovsxwq", "pmovsxdq",
		"pblendvb",
	},
	"fma":   {"vfmadd231sd"},
	"movbe": {"movbeqq", "movbeq", "movbell", "movbel", "movbe"},
	"lzcnt": {"lzcntq", "lzcntl", "lzcnt"},
}

// Test to use POPCNT instruction, if available
func TestPopCnt(t *testing.T) {
	for _, tt := range []struct {
		x    uint64

	"MASKMOVQ",
	"MAXPD",
	"MAXPS",
	"MAXSD",
	"MAXSS",
	"MFENCE",
	"MINPD",
	"MINPS",
	"MINSD",
	"MINSS",
	"MONITOR",
	"MOVAPD",
	"MOVAPS",
	"MOVB",
	"MOVBEL",
	"MOVBEQ",
	"MOVBEW",
	"MOVBLSX",
	"MOVBLZX",
	"MOVBQSX",
	"MOVBQZX",
	"MOVBWSX",
	"MOVBWZX",
	"MOVDDUP",
	"MOVHLPS",
	"MOVHPD",
	"MOVHPS",
	"MOVL",
	"MOVLHPS",
	"MOVLPD",

		{name: "MOVBEQload", argLength: 2, reg: gpload, asm: "MOVBEQ", aux: "SymOff", typ: "UInt64", faultOnNilArg0: true, symEffect: "Read"}, // load and swap 8 bytes from arg0+auxint+aux. arg1=mem
		{name: "MOVBEQstore", argLength: 3, reg: gpstore, asm: "MOVBEQ", aux: "SymOff", typ: "Mem", faultOnNilArg0: true, symEffect: "Write"}, // swap and store 8 bytes in arg1 to arg0+auxint+aux. arg2=mem

	MOVBEL (R11), R11                       // 450f38f01b
	MOVBEQ DX, (BX)                         // 480f38f113
	MOVBEQ R11, (BX)                        // 4c0f38f11b
	MOVBEQ DX, (R11)                        // 490f38f113
	MOVBEQ R11, (R11)                       // 4d0f38f11b
	MOVBEQ (BX), DX                         // 480f38f013
	MOVBEQ (R11), DX                        // 490f38f013
	MOVBEQ (BX), R11                        // 4c0f38f01b