diff --git a/arm/armasm/decode.go b/arm/armasm/decode.go
index 6b4d738..f61ac12 100644
--- a/arm/armasm/decode.go
+++ b/arm/armasm/decode.go
@@ -17,7 +17,9 @@
 // If x matches the format, then the rest of the fields describe how to interpret x.
 // The opBits describe bits that should be extracted from x and added to the opcode.
 // For example opBits = 0x1234 means that the value
+//
 //	(2 bits at offset 1) followed by (4 bits at offset 3)
+//
 // should be added to op.
 // Finally the args describe how to decode the instruction arguments.
 // args is stored as a fixed-size array; if there are fewer than len(args) arguments,
@@ -233,9 +235,9 @@
 		typ, count := decodeShift(x)
 		// ROR #0 here means ROR #0, but decodeShift rewrites to RRX #1.
 		if typ == RotateRightExt {
-			return Reg(Rm)
+			return Rm
 		}
-		return RegShift{Rm, typ, uint8(count)}
+		return RegShift{Rm, typ, count}
 
 	case arg_R_shift_R:
 		Rm := Reg(x & (1<<4 - 1))
@@ -249,7 +251,7 @@
 		if typ == ShiftLeft && count == 0 {
 			return Reg(Rm)
 		}
-		return RegShift{Rm, typ, uint8(count)}
+		return RegShift{Rm, typ, count}
 
 	case arg_R1_0:
 		return Reg((x & (1<<4 - 1)))
diff --git a/ppc64/ppc64asm/field.go b/ppc64/ppc64asm/field.go
index 882c91a..13df063 100644
--- a/ppc64/ppc64asm/field.go
+++ b/ppc64/ppc64asm/field.go
@@ -67,7 +67,7 @@
 // the sequence of bitfields is reasonable.
 func (bs BitFields) parse(i [2]uint32) (u uint64, Bits uint8) {
 	for _, b := range bs {
-		u = (uint64(u) << b.Bits) | uint64(b.Parse(i))
+		u = (u << b.Bits) | uint64(b.Parse(i))
 		Bits += b.Bits
 	}
 	return u, Bits