BEQ	R1, 2(PC)
	JAL	0(R1)		// CALL (R1)	// 0020f809
	BEQ	R1, 2(PC)
	JAL	foo+0(SB)	// CALL foo(SB)	// 0c000021

//
// BEQ/BNE
//
//	LBRA rreg ',' rel
//	{
//		outcode(int($1), &$2, 0, &$4);
//	}
label1:
	BEQ	R1, 1(PC)	// BEQ R1, 1(PC)	// 10200001
	BEQ	R1, label1	// BEQ R1, 18		// 1020fffd

//	LBRA rreg ',' sreg ',' rel
//	{
//		outcode(int($1), &$2, 0, &$4);
//	}
label2:

	VINSHRX R1, R2, V3                      // 1061134f
	VINSHVLX R1, V2, V3                     // 1061104f
	VINSHVRX R1, V2, V3                     // 1061114f
	VINSW R1, $4, V3                        // 106408cf
	VINSWLX R1, R2, V3                      // 1061128f
	VINSWRX R1, R2, V3                      // 1061138f
	VINSWVLX R1, V2, V3                     // 1061108f
	VINSWVRX R1, V2, V3                     // 1061118f

	MOVF	R1, F2             // ERROR "illegal combination"
	MOVD	R1, F2             // ERROR "illegal combination"
	MOVF	R1, R1             // ERROR "illegal combination"
	MOVD	R1, R2             // ERROR "illegal combination"
	MOVFW	R1, R2             // ERROR "illegal combination"
	MOVDW	R1, R2             // ERROR "illegal combination"
	MOVWF	R1, R2             // ERROR "illegal combination"

	BIC R12@>13, R12, R19                      // 9335ec8a
	BICSW R25->20, R3, R20                     // 7450b96a
	BICS R19->12, R1, R23                      // 3730b3ea
	BICS R19, R1, R23                          // 370033ea
	BICS R19>>0, R1, R23                       // 370073ea
	CALL -1(PC)                                // ffffff97
	CALL (R15)                                 // e0013fd6

	AND	$-2, R1               // a517fffe
	AND	$-65536, R1           // c01bffff0000
	AND	$1, R1                // c0a100000001b980001a
	ANDW	R1, R2                // 1421
	ANDW	R1, R2, R3            // b9f42031
	ANDW	$1, R1                // c01b00000001
	ANDW	$131071, R1           // a5160001
	ANDW	$65536, R1            // c01b00010000
	ANDW	$-2, R1               // a517fffe
	OR	R1, R2                // b9810021

// including forms involving multiple registers such as R1:R2.
func (p *Parser) register(name string, prefix rune) (r1, r2 int16, scale int8, ok bool) {
	// R1 or R(1) R1:R2 R1,R2 R1+R2, or R1*scale.
	r1, ok = p.registerReference(name)
	if !ok {
		return
	}
	if prefix != 0 && prefix != '*' { // *AX is OK.

	{"1024", "1024"},
	{"12(R(1))", "12(R1)"},
	{"12(R13)", "12(R13)"},
	{"R0", "R0"},
	{"R0->(32-1)", "R0->31"},
	{"R0<<R1", "R0<<R1"},
	{"R0>>R(1)", "R0>>R1"},
	{"R0@>(32-1)", "R0@>31"},
	{"R1", "R1"},
	{"R11", "R11"},
	{"R12", "R12"},
	{"R13", "R13"},
	{"R14", "R14"},
	{"R15", "R15"},
	{"R1<<2(R3)", "R1<<2(R3)"},
	{"R(1)<<2(R(3))", "R1<<2(R3)"},
	{"R2", "R2"},
	{"R3", "R3"},

	FLDPQ	(R0), (R1, R2)                                   // ERROR "invalid register pair"
	FLDPQ	(R1), (F2, F2)                                   // ERROR "constrained unpredictable behavior"
	FSTPQ	(R1, R2), (R0)                                   // ERROR "invalid register pair"
	FLDPD	(R0), (R1, R2)                                   // ERROR "invalid register pair"

    private static boolean repositoryEquals(RemoteRepository r1, RemoteRepository r2) {
        if (r1 == r2) {
            return true;
        }

        return Objects.equals(r1.getId(), r2.getId())
                && Objects.equals(r1.getUrl(), r2.getUrl())
                && policyEquals(r1.getPolicy(false), r2.getPolicy(false))
                && policyEquals(r1.getPolicy(true), r2.getPolicy(true));
    }

    private static boolean repositoryEquals(ArtifactRepository r1, ArtifactRepository r2) {
        if (r1 == r2) {
            return true;
        }

        return Objects.equals(r1.getId(), r2.getId())
                && Objects.equals(r1.getUrl(), r2.getUrl())
                && repositoryPolicyEquals(r1.getReleases(), r2.getReleases())
                && repositoryPolicyEquals(r1.getSnapshots(), r2.getSnapshots());
    }