SOCK_CLOEXEC                     = 0x400000
	SOCK_DGRAM                       = 0x2
	SOCK_NONBLOCK                    = 0x4000
	SOCK_STREAM                      = 0x1
	SOL_SOCKET                       = 0xffff
	SO_ACCEPTCONN                    = 0x8000
	SO_ATTACH_BPF                    = 0x34
	SO_ATTACH_REUSEPORT_CBPF         = 0x35
	SO_ATTACH_REUSEPORT_EBPF         = 0x36
	SO_BINDTODEVICE                  = 0xd

	IP_IPSEC_REMOTE_AUTH              = 0x1c
	IP_IPSEC_REMOTE_CRED              = 0x1a
	IP_IPSEC_REMOTE_ID                = 0x18
	IP_MAXPACKET                      = 0xffff
	IP_MAX_MEMBERSHIPS                = 0xfff
	IP_MF                             = 0x2000
	IP_MINTTL                         = 0x20
	IP_MIN_MEMBERSHIPS                = 0xf
	IP_MSS                            = 0x240

	IP_IPSEC_REMOTE_AUTH              = 0x1c
	IP_IPSEC_REMOTE_CRED              = 0x1a
	IP_IPSEC_REMOTE_ID                = 0x18
	IP_MAXPACKET                      = 0xffff
	IP_MAX_MEMBERSHIPS                = 0xfff
	IP_MF                             = 0x2000
	IP_MINTTL                         = 0x20
	IP_MIN_MEMBERSHIPS                = 0xf
	IP_MSS                            = 0x240

}

func countPrefix(inst *Inst, target Prefix) int {
	n := 0
	for _, p := range inst.Prefix {
		if p&0xFF == target&0xFF {
			n++
		}
	}
	return n
}

func markLastImplicit(inst *Inst, prefix Prefix) bool {
	for i := len(inst.Prefix) - 1; i >= 0; i-- {
		p := inst.Prefix[i]
		if p&0xFF == prefix {
			inst.Prefix[i] |= PrefixImplicit
			return true
		}
	}
	return false
}

(Trunc64to8  (And64 (Const64 [y]) x)) && y&0xFF == 0xFF => (Trunc64to8 x)
(Trunc64to16 (And64 (Const64 [y]) x)) && y&0xFFFF == 0xFFFF => (Trunc64to16 x)
(Trunc64to32 (And64 (Const64 [y]) x)) && y&0xFFFFFFFF == 0xFFFFFFFF => (Trunc64to32 x)
(Trunc32to8  (And32 (Const32 [y]) x)) && y&0xFF == 0xFF => (Trunc32to8 x)
(Trunc32to16 (And32 (Const32 [y]) x)) && y&0xFFFF == 0xFFFF => (Trunc32to16 x)

	IPV6_LEAVE_GROUP                        = 0xd
	IPV6_MAXHLIM                            = 0xff
	IPV6_MAXOPTHDR                          = 0x800
	IPV6_MAXPACKET                          = 0xffff
	IPV6_MAX_GROUP_SRC_FILTER               = 0x200
	IPV6_MAX_MEMBERSHIPS                    = 0xfff
	IPV6_MAX_SOCK_SRC_FILTER                = 0x80
	IPV6_MIN_MEMBERSHIPS                    = 0x1f

	IP_IPSEC_REMOTE_AUTH              = 0x1c
	IP_IPSEC_REMOTE_CRED              = 0x1a
	IP_IPSEC_REMOTE_ID                = 0x18
	IP_MAXPACKET                      = 0xffff
	IP_MAX_MEMBERSHIPS                = 0xfff
	IP_MF                             = 0x2000
	IP_MINTTL                         = 0x20
	IP_MIN_MEMBERSHIPS                = 0xf
	IP_MSS                            = 0x240

		}
	}
}

func TestIsInCharacterRange(t *testing.T) {
	invalid := []rune{
		utf8.MaxRune + 1,
		0xD800, // surrogate min
		0xDFFF, // surrogate max
		-1,
	}
	for _, r := range invalid {
		if isInCharacterRange(r) {
			t.Errorf("rune %U considered valid", r)
		}
	}
}

var procInstTests = []struct {
	input  string

(RISBGZ x {r}) && r == s390x.NewRotateParams(48, 63, 0) => (MOVHZreg x)
(RISBGZ x {r}) && r == s390x.NewRotateParams(32, 63, 0) => (MOVWZreg x)

// Use sign/zero extend instead of ANDW.
(ANDWconst [0x00ff] x) => (MOVBZreg x)
(ANDWconst [0xffff] x) => (MOVHZreg x)

// Strength reduce multiplication to the sum (or difference) of two powers of two.
//
// Examples:
//     5x -> 4x + 1x
//    10x -> 8x + 2x
//   120x -> 128x - 8x

(AtomicAdd(64|32) ...) => (LoweredAtomicAdd(64|32) ...)

// AtomicAnd8(ptr,val) => LoweredAtomicAnd32(ptr&^3, ^((uint8(val) ^ 0xff) << ((ptr & 3) * 8)))
(AtomicAnd8 ptr val mem) =>
	(LoweredAtomicAnd32 (ANDI <typ.Uintptr> [^3] ptr)
		(NOT <typ.UInt32> (SLL <typ.UInt32> (XORI <typ.UInt32> [0xff] (ZeroExt8to32 val))
			(SLLI <typ.UInt64> [3] (ANDI <typ.UInt64> [3] ptr)))) mem)

(AtomicAnd32 ...) => (LoweredAtomicAnd32 ...)