316 lines
		
	
	
		
			16 KiB
		
	
	
	
		
			Go
		
	
	
	
			
		
		
	
	
			316 lines
		
	
	
		
			16 KiB
		
	
	
	
		
			Go
		
	
	
	
| // Copyright 2013 The Go Authors. All rights reserved.
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| // Use of this source code is governed by a BSD-style
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| // license that can be found in the LICENSE file.
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| 
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| package pointer
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| 
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| // This package defines the treatment of intrinsics, i.e. library
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| // functions requiring special analytical treatment.
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| //
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| // Most of these are C or assembly functions, but even some Go
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| // functions require may special treatment if the analysis completely
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| // replaces the implementation of an API such as reflection.
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| 
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| // TODO(adonovan): support a means of writing analytic summaries in
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| // the target code, so that users can summarise the effects of their
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| // own C functions using a snippet of Go.
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| 
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| import (
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| 	"code.google.com/p/go.tools/ssa"
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| )
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| 
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| // Instances of 'intrinsic' generate analysis constraints for calls to
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| // intrinsic functions.
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| type intrinsic func(a *analysis, cgn *cgnode)
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| 
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| // Initialized in explicit init() to defeat (spurious) initialization
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| // cycle error.
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| var intrinsicsByName map[string]intrinsic
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| 
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| func init() {
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| 	// Key strings are from Function.String().
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| 	// That little dot ۰ is an Arabic zero numeral (U+06F0),
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| 	// categories [Nd].
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| 	intrinsicsByName = map[string]intrinsic{
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| 		// reflect.Value methods.
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| 		"(reflect.Value).Addr":            ext۰reflect۰Value۰Addr,
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| 		"(reflect.Value).Bool":            ext۰NoEffect,
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| 		"(reflect.Value).Bytes":           ext۰reflect۰Value۰Bytes,
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| 		"(reflect.Value).Call":            ext۰reflect۰Value۰Call,
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| 		"(reflect.Value).CallSlice":       ext۰reflect۰Value۰CallSlice,
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| 		"(reflect.Value).CanAddr":         ext۰NoEffect,
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| 		"(reflect.Value).CanInterface":    ext۰NoEffect,
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| 		"(reflect.Value).CanSet":          ext۰NoEffect,
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| 		"(reflect.Value).Cap":             ext۰NoEffect,
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| 		"(reflect.Value).Close":           ext۰NoEffect,
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| 		"(reflect.Value).Complex":         ext۰NoEffect,
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| 		"(reflect.Value).Convert":         ext۰reflect۰Value۰Convert,
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| 		"(reflect.Value).Elem":            ext۰reflect۰Value۰Elem,
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| 		"(reflect.Value).Field":           ext۰reflect۰Value۰Field,
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| 		"(reflect.Value).FieldByIndex":    ext۰reflect۰Value۰FieldByIndex,
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| 		"(reflect.Value).FieldByName":     ext۰reflect۰Value۰FieldByName,
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| 		"(reflect.Value).FieldByNameFunc": ext۰reflect۰Value۰FieldByNameFunc,
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| 		"(reflect.Value).Float":           ext۰NoEffect,
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| 		"(reflect.Value).Index":           ext۰reflect۰Value۰Index,
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| 		"(reflect.Value).Int":             ext۰NoEffect,
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| 		"(reflect.Value).Interface":       ext۰reflect۰Value۰Interface,
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| 		"(reflect.Value).InterfaceData":   ext۰NoEffect,
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| 		"(reflect.Value).IsNil":           ext۰NoEffect,
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| 		"(reflect.Value).IsValid":         ext۰NoEffect,
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| 		"(reflect.Value).Kind":            ext۰NoEffect,
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| 		"(reflect.Value).Len":             ext۰NoEffect,
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| 		"(reflect.Value).MapIndex":        ext۰reflect۰Value۰MapIndex,
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| 		"(reflect.Value).MapKeys":         ext۰reflect۰Value۰MapKeys,
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| 		"(reflect.Value).Method":          ext۰reflect۰Value۰Method,
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| 		"(reflect.Value).MethodByName":    ext۰reflect۰Value۰MethodByName,
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| 		"(reflect.Value).NumField":        ext۰NoEffect,
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| 		"(reflect.Value).NumMethod":       ext۰NoEffect,
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| 		"(reflect.Value).OverflowComplex": ext۰NoEffect,
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| 		"(reflect.Value).OverflowFloat":   ext۰NoEffect,
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| 		"(reflect.Value).OverflowInt":     ext۰NoEffect,
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| 		"(reflect.Value).OverflowUint":    ext۰NoEffect,
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| 		"(reflect.Value).Pointer":         ext۰NoEffect,
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| 		"(reflect.Value).Recv":            ext۰reflect۰Value۰Recv,
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| 		"(reflect.Value).Send":            ext۰reflect۰Value۰Send,
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| 		"(reflect.Value).Set":             ext۰reflect۰Value۰Set,
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| 		"(reflect.Value).SetBool":         ext۰NoEffect,
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| 		"(reflect.Value).SetBytes":        ext۰reflect۰Value۰SetBytes,
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| 		"(reflect.Value).SetComplex":      ext۰NoEffect,
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| 		"(reflect.Value).SetFloat":        ext۰NoEffect,
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| 		"(reflect.Value).SetInt":          ext۰NoEffect,
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| 		"(reflect.Value).SetLen":          ext۰NoEffect,
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| 		"(reflect.Value).SetMapIndex":     ext۰reflect۰Value۰SetMapIndex,
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| 		"(reflect.Value).SetPointer":      ext۰reflect۰Value۰SetPointer,
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| 		"(reflect.Value).SetString":       ext۰NoEffect,
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| 		"(reflect.Value).SetUint":         ext۰NoEffect,
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| 		"(reflect.Value).Slice":           ext۰reflect۰Value۰Slice,
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| 		"(reflect.Value).String":          ext۰NoEffect,
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| 		"(reflect.Value).TryRecv":         ext۰reflect۰Value۰Recv,
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| 		"(reflect.Value).TrySend":         ext۰reflect۰Value۰Send,
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| 		"(reflect.Value).Type":            ext۰NoEffect,
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| 		"(reflect.Value).Uint":            ext۰NoEffect,
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| 		"(reflect.Value).UnsafeAddr":      ext۰NoEffect,
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| 
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| 		// Standalone reflect.* functions.
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| 		"reflect.Append":      ext۰reflect۰Append,
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| 		"reflect.AppendSlice": ext۰reflect۰AppendSlice,
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| 		"reflect.Copy":        ext۰reflect۰Copy,
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| 		"reflect.ChanOf":      ext۰reflect۰ChanOf,
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| 		"reflect.DeepEqual":   ext۰NoEffect,
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| 		"reflect.Indirect":    ext۰reflect۰Indirect,
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| 		"reflect.MakeChan":    ext۰reflect۰MakeChan,
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| 		"reflect.MakeFunc":    ext۰reflect۰MakeFunc,
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| 		"reflect.MakeMap":     ext۰reflect۰MakeMap,
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| 		"reflect.MakeSlice":   ext۰reflect۰MakeSlice,
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| 		"reflect.MapOf":       ext۰reflect۰MapOf,
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| 		"reflect.New":         ext۰reflect۰New,
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| 		"reflect.NewAt":       ext۰reflect۰NewAt,
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| 		"reflect.PtrTo":       ext۰reflect۰PtrTo,
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| 		"reflect.Select":      ext۰reflect۰Select,
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| 		"reflect.SliceOf":     ext۰reflect۰SliceOf,
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| 		"reflect.TypeOf":      ext۰reflect۰TypeOf,
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| 		"reflect.ValueOf":     ext۰reflect۰ValueOf,
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| 		"reflect.Zero":        ext۰reflect۰Zero,
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| 		"reflect.init":        ext۰NoEffect,
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| 
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| 		// *reflect.rtype methods
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| 		"(*reflect.rtype).Align":           ext۰NoEffect,
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| 		"(*reflect.rtype).AssignableTo":    ext۰NoEffect,
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| 		"(*reflect.rtype).Bits":            ext۰NoEffect,
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| 		"(*reflect.rtype).ChanDir":         ext۰NoEffect,
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| 		"(*reflect.rtype).ConvertibleTo":   ext۰NoEffect,
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| 		"(*reflect.rtype).Elem":            ext۰reflect۰rtype۰Elem,
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| 		"(*reflect.rtype).Field":           ext۰reflect۰rtype۰Field,
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| 		"(*reflect.rtype).FieldAlign":      ext۰NoEffect,
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| 		"(*reflect.rtype).FieldByIndex":    ext۰reflect۰rtype۰FieldByIndex,
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| 		"(*reflect.rtype).FieldByName":     ext۰reflect۰rtype۰FieldByName,
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| 		"(*reflect.rtype).FieldByNameFunc": ext۰reflect۰rtype۰FieldByNameFunc,
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| 		"(*reflect.rtype).Implements":      ext۰NoEffect,
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| 		"(*reflect.rtype).In":              ext۰reflect۰rtype۰In,
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| 		"(*reflect.rtype).IsVariadic":      ext۰NoEffect,
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| 		"(*reflect.rtype).Key":             ext۰reflect۰rtype۰Key,
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| 		"(*reflect.rtype).Kind":            ext۰NoEffect,
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| 		"(*reflect.rtype).Len":             ext۰NoEffect,
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| 		"(*reflect.rtype).Method":          ext۰reflect۰rtype۰Method,
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| 		"(*reflect.rtype).MethodByName":    ext۰reflect۰rtype۰MethodByName,
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| 		"(*reflect.rtype).Name":            ext۰NoEffect,
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| 		"(*reflect.rtype).NumField":        ext۰NoEffect,
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| 		"(*reflect.rtype).NumIn":           ext۰NoEffect,
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| 		"(*reflect.rtype).NumMethod":       ext۰NoEffect,
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| 		"(*reflect.rtype).NumOut":          ext۰NoEffect,
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| 		"(*reflect.rtype).Out":             ext۰reflect۰rtype۰Out,
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| 		"(*reflect.rtype).PkgPath":         ext۰NoEffect,
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| 		"(*reflect.rtype).Size":            ext۰NoEffect,
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| 		"(*reflect.rtype).String":          ext۰NoEffect,
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| 
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| 		// Other packages.
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| 		"bytes.Equal":                           ext۰NoEffect,
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| 		"bytes.IndexByte":                       ext۰NoEffect,
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| 		"crypto/aes.decryptBlockAsm":            ext۰NoEffect,
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| 		"crypto/aes.encryptBlockAsm":            ext۰NoEffect,
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| 		"crypto/aes.expandKeyAsm":               ext۰NoEffect,
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| 		"crypto/aes.hasAsm":                     ext۰NoEffect,
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| 		"crypto/md5.block":                      ext۰NoEffect,
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| 		"crypto/rc4.xorKeyStream":               ext۰NoEffect,
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| 		"crypto/sha1.block":                     ext۰NoEffect,
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| 		"hash/crc32.castagnoliSSE42":            ext۰NoEffect,
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| 		"hash/crc32.haveSSE42":                  ext۰NoEffect,
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| 		"math.Abs":                              ext۰NoEffect,
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| 		"math.Acos":                             ext۰NoEffect,
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| 		"math.Asin":                             ext۰NoEffect,
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| 		"math.Atan":                             ext۰NoEffect,
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| 		"math.Atan2":                            ext۰NoEffect,
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| 		"math.Ceil":                             ext۰NoEffect,
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| 		"math.Cos":                              ext۰NoEffect,
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| 		"math.Dim":                              ext۰NoEffect,
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| 		"math.Exp":                              ext۰NoEffect,
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| 		"math.Exp2":                             ext۰NoEffect,
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| 		"math.Expm1":                            ext۰NoEffect,
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| 		"math.Float32bits":                      ext۰NoEffect,
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| 		"math.Float32frombits":                  ext۰NoEffect,
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| 		"math.Float64bits":                      ext۰NoEffect,
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| 		"math.Float64frombits":                  ext۰NoEffect,
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| 		"math.Floor":                            ext۰NoEffect,
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| 		"math.Frexp":                            ext۰NoEffect,
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| 		"math.Hypot":                            ext۰NoEffect,
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| 		"math.Ldexp":                            ext۰NoEffect,
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| 		"math.Log":                              ext۰NoEffect,
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| 		"math.Log10":                            ext۰NoEffect,
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| 		"math.Log1p":                            ext۰NoEffect,
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| 		"math.Log2":                             ext۰NoEffect,
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| 		"math.Max":                              ext۰NoEffect,
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| 		"math.Min":                              ext۰NoEffect,
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| 		"math.Mod":                              ext۰NoEffect,
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| 		"math.Modf":                             ext۰NoEffect,
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| 		"math.Remainder":                        ext۰NoEffect,
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| 		"math.Sin":                              ext۰NoEffect,
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| 		"math.Sincos":                           ext۰NoEffect,
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| 		"math.Sqrt":                             ext۰NoEffect,
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| 		"math.Tan":                              ext۰NoEffect,
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| 		"math.Trunc":                            ext۰NoEffect,
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| 		"math/big.addMulVVW":                    ext۰NoEffect,
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| 		"math/big.addVV":                        ext۰NoEffect,
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| 		"math/big.addVW":                        ext۰NoEffect,
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| 		"math/big.bitLen":                       ext۰NoEffect,
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| 		"math/big.divWVW":                       ext۰NoEffect,
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| 		"math/big.divWW":                        ext۰NoEffect,
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| 		"math/big.mulAddVWW":                    ext۰NoEffect,
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| 		"math/big.mulWW":                        ext۰NoEffect,
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| 		"math/big.shlVU":                        ext۰NoEffect,
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| 		"math/big.shrVU":                        ext۰NoEffect,
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| 		"math/big.subVV":                        ext۰NoEffect,
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| 		"math/big.subVW":                        ext۰NoEffect,
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| 		"net.runtime_Semacquire":                ext۰NoEffect,
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| 		"net.runtime_Semrelease":                ext۰NoEffect,
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| 		"net.runtime_pollClose":                 ext۰NoEffect,
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| 		"net.runtime_pollOpen":                  ext۰NoEffect,
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| 		"net.runtime_pollReset":                 ext۰NoEffect,
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| 		"net.runtime_pollServerInit":            ext۰NoEffect,
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| 		"net.runtime_pollSetDeadline":           ext۰NoEffect,
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| 		"net.runtime_pollUnblock":               ext۰NoEffect,
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| 		"net.runtime_pollWait":                  ext۰NoEffect,
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| 		"os.epipecheck":                         ext۰NoEffect,
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| 		"runtime.BlockProfile":                  ext۰NoEffect,
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| 		"runtime.Breakpoint":                    ext۰NoEffect,
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| 		"runtime.CPUProfile":                    ext۰NotYetImplemented,
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| 		"runtime.Caller":                        ext۰NoEffect,
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| 		"runtime.FuncForPC":                     ext۰NotYetImplemented,
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| 		"runtime.GC":                            ext۰NoEffect,
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| 		"runtime.GOMAXPROCS":                    ext۰NoEffect,
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| 		"runtime.Goexit":                        ext۰NoEffect,
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| 		"runtime.GoroutineProfile":              ext۰NoEffect,
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| 		"runtime.Gosched":                       ext۰NoEffect,
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| 		"runtime.MemProfile":                    ext۰NoEffect,
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| 		"runtime.NumCPU":                        ext۰NoEffect,
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| 		"runtime.NumGoroutine":                  ext۰NoEffect,
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| 		"runtime.ReadMemStats":                  ext۰NoEffect,
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| 		"runtime.SetBlockProfileRate":           ext۰NoEffect,
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| 		"runtime.SetCPUProfileRate":             ext۰NoEffect,
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| 		"runtime.SetFinalizer":                  ext۰NotYetImplemented,
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| 		"runtime.Stack":                         ext۰NoEffect,
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| 		"runtime.ThreadCreateProfile":           ext۰NoEffect,
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| 		"runtime.funcentry_go":                  ext۰NoEffect,
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| 		"runtime.funcline_go":                   ext۰NoEffect,
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| 		"runtime.funcname_go":                   ext۰NoEffect,
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| 		"runtime.getgoroot":                     ext۰NoEffect,
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| 		"runtime/pprof.runtime_cyclesPerSecond": ext۰NoEffect,
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| 		"strings.IndexByte":                     ext۰NoEffect,
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| 		"sync.runtime_Semacquire":               ext۰NoEffect,
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| 		"sync.runtime_Semrelease":               ext۰NoEffect,
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| 		"sync.runtime_Syncsemacquire":           ext۰NoEffect,
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| 		"sync.runtime_Syncsemcheck":             ext۰NoEffect,
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| 		"sync.runtime_Syncsemrelease":           ext۰NoEffect,
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| 		"sync/atomic.AddInt32":                  ext۰NoEffect,
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| 		"sync/atomic.AddUint32":                 ext۰NoEffect,
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| 		"sync/atomic.CompareAndSwapInt32":       ext۰NoEffect,
 | ||
| 		"sync/atomic.CompareAndSwapUint32":      ext۰NoEffect,
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| 		"sync/atomic.CompareAndSwapUint64":      ext۰NoEffect,
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| 		"sync/atomic.CompareAndSwapUintptr":     ext۰NoEffect,
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| 		"sync/atomic.LoadInt32":                 ext۰NoEffect,
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| 		"sync/atomic.LoadUint32":                ext۰NoEffect,
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| 		"sync/atomic.LoadUint64":                ext۰NoEffect,
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| 		"sync/atomic.StoreInt32":                ext۰NoEffect,
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| 		"sync/atomic.StoreUint32":               ext۰NoEffect,
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| 		"syscall.Close":                         ext۰NoEffect,
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| 		"syscall.Exit":                          ext۰NoEffect,
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| 		"syscall.Getpid":                        ext۰NoEffect,
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| 		"syscall.Getwd":                         ext۰NoEffect,
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| 		"syscall.Kill":                          ext۰NoEffect,
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| 		"syscall.RawSyscall":                    ext۰NoEffect,
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| 		"syscall.RawSyscall6":                   ext۰NoEffect,
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| 		"syscall.Syscall":                       ext۰NoEffect,
 | ||
| 		"syscall.Syscall6":                      ext۰NoEffect,
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| 		"syscall.runtime_AfterFork":             ext۰NoEffect,
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| 		"syscall.runtime_BeforeFork":            ext۰NoEffect,
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| 		"time.Sleep":                            ext۰NoEffect,
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| 		"time.now":                              ext۰NoEffect,
 | ||
| 		"time.startTimer":                       ext۰NoEffect,
 | ||
| 		"time.stopTimer":                        ext۰NoEffect,
 | ||
| 	}
 | ||
| }
 | ||
| 
 | ||
| // findIntrinsic returns the constraint generation function for an
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| // intrinsic function fn, or nil if the function should be handled normally.
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| //
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| func (a *analysis) findIntrinsic(fn *ssa.Function) intrinsic {
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| 	// Consult the *Function-keyed cache.
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| 	// A cached nil indicates a normal non-intrinsic function.
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| 	impl, ok := a.intrinsics[fn]
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| 	if !ok {
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| 		impl = intrinsicsByName[fn.String()] // may be nil
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| 
 | ||
| 		if fn.Pkg != nil && a.reflectValueObj != nil && a.reflectValueObj.Pkg() == fn.Pkg.Object {
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| 			if !a.config.Reflection {
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| 				impl = ext۰NoEffect // reflection disabled
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| 			} else if impl == nil {
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| 				// Ensure all "reflect" code is treated intrinsically.
 | ||
| 				impl = ext۰NotYetImplemented
 | ||
| 			}
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| 		}
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| 
 | ||
| 		a.intrinsics[fn] = impl
 | ||
| 	}
 | ||
| 	return impl
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| }
 | ||
| 
 | ||
| // A trivial intrinsic suitable for any function that does not:
 | ||
| // 1) induce aliases between its arguments or any global variables;
 | ||
| // 2) call any functions; or
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| // 3) create any labels.
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| //
 | ||
| // Many intrinsics (such as CompareAndSwapInt32) have a fourth kind of
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| // effect: loading or storing through a pointer.  Though these could
 | ||
| // be significant, we deliberately ignore them because they are
 | ||
| // generally not worth the effort.
 | ||
| //
 | ||
| // We sometimes violate condition #3 if the function creates only
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| // non-function labels, as the control-flow graph is still sound.
 | ||
| //
 | ||
| func ext۰NoEffect(a *analysis, cgn *cgnode) {}
 | ||
| 
 | ||
| func ext۰NotYetImplemented(a *analysis, cgn *cgnode) {
 | ||
| 	// TODO(adonovan): enable this warning when we've implemented
 | ||
| 	// enough that it's not unbearably annoying.
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| 	// a.warnf(fn.Pos(), "unsound: intrinsic treatment of %s not yet implemented", fn)
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| }
 |