[chore] Update gin to v1.9.0 (#1553)

vendor/github.com/twitchyliquid64/golang-asm/obj/s390x/rotate.go

@@ -0,0 +1,47 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package s390x
+
+// RotateParams represents the immediates required for a "rotate
+// then ... selected bits instruction".
+//
+// The Start and End values are the indexes that represent
+// the masked region. They are inclusive and are in big-
+// endian order (bit 0 is the MSB, bit 63 is the LSB). They
+// may wrap around.
+//
+// Some examples:
+//
+// Masked region             | Start | End
+// --------------------------+-------+----
+// 0x00_00_00_00_00_00_00_0f | 60    | 63
+// 0xf0_00_00_00_00_00_00_00 | 0     | 3
+// 0xf0_00_00_00_00_00_00_0f | 60    | 3
+//
+// The Amount value represents the amount to rotate the
+// input left by. Note that this rotation is performed
+// before the masked region is used.
+type RotateParams struct {
+	Start  uint8 // big-endian start bit index [0..63]
+	End    uint8 // big-endian end bit index [0..63]
+	Amount uint8 // amount to rotate left
+}
+
+func NewRotateParams(start, end, amount int64) RotateParams {
+	if start&^63 != 0 {
+		panic("start out of bounds")
+	}
+	if end&^63 != 0 {
+		panic("end out of bounds")
+	}
+	if amount&^63 != 0 {
+		panic("amount out of bounds")
+	}
+	return RotateParams{
+		Start:  uint8(start),
+		End:    uint8(end),
+		Amount: uint8(amount),
+	}
+}