1 // Copyright 2017 The Go Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style 3 // license that can be found in the LICENSE file. 4 5 package x86 6 7 type argList [6]uint8 8 9 type ytab struct { 10 zcase uint8 11 zoffset uint8 12 13 // Last arg is usually destination. 14 // For unary instructions unaryDst is used to determine 15 // if single argument is a source or destination. 16 args argList 17 } 18 19 // Returns true if yt is compatible with args. 20 // 21 // Elements from args and yt.args are used to 22 // to index ycover table like `ycover[args[i]+yt.args[i]]`. 23 // This means that args should contain values that already 24 // multiplied by Ymax. 25 func (yt *ytab) match(args []int) bool { 26 // Trailing Yxxx check is required to avoid a case 27 // where shorter arg list is matched. 28 // If we had exact yt.args length, it could be `yt.argc != len(args)`. 29 if len(args) < len(yt.args) && yt.args[len(args)] != Yxxx { 30 return false 31 } 32 33 for i := range args { 34 if ycover[args[i]+int(yt.args[i])] == 0 { 35 return false 36 } 37 } 38 39 return true 40 } 41
