EXTSWCC R3, R4                  // 7c6407b5
	RLWMI $7, R3, $4026531855, R6   // 50663f06
	RLWMI $7, R3, $1, R6            // 50663ffe
	RLWMI $7, R3, $2147483648, R6   // 50663800
	RLWMI $7, R3, $65535, R6        // 50663c3e
	RLWMI $7, R3, $16, $31, R6      // 50663c3e
	RLWMICC $7, R3, $65535, R6      // 50663c3f
	RLWMICC $7, R3, $16, $31, R6    // 50663c3f
	RLWNM $3, R4, $7, R6            // 54861f7e

func mergePPC64MovwzregRlwinm(rlw int64) int64 {
	_, mb, me, _ := DecodePPC64RotateMask(rlw)
	if mb > me {
		return 0
	}
	return rlw
}

// Test if AND feeding into an ANDconst can be merged. Return the encoded RLWINM constant,
// or 0 if they cannot be merged.
func mergePPC64RlwinmAnd(rlw int64, mask uint32) int64 {
	r, _, _, mask_rlw := DecodePPC64RotateMask(rlw)

(AND (MOVDconst [m]) (ROTLWconst [r] x)) && isPPC64WordRotateMask(m) => (RLWINM [encodePPC64RotateMask(r,m,32)] x)
(ANDconst [m] (ROTLW x r)) && isPPC64WordRotateMask(m) => (RLWNM [encodePPC64RotateMask(0,m,32)] x r)
(AND (MOVDconst [m]) (ROTLW x r)) && isPPC64WordRotateMask(m) => (RLWNM [encodePPC64RotateMask(0,m,32)] x r)

// Note, any rotated word bitmask is still a valid word bitmask.