| // Copyright 2013 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 pointer |
| |
| // This package defines the treatment of intrinsics, i.e. library |
| // functions requiring special analytical treatment. |
| // |
| // Most of these are C or assembly functions, but even some Go |
| // functions require may special treatment if the analysis completely |
| // replaces the implementation of an API such as reflection. |
| |
| // TODO(adonovan): support a means of writing analytic summaries in |
| // the target code, so that users can summarise the effects of their |
| // own C functions using a snippet of Go. |
| |
| import ( |
| "code.google.com/p/go.tools/ssa" |
| ) |
| |
| // Instances of 'intrinsic' generate analysis constraints for calls to |
| // intrinsic functions. |
| type intrinsic func(a *analysis, cgn *cgnode) |
| |
| // Initialized in explicit init() to defeat (spurious) initialization |
| // cycle error. |
| var intrinsicsByName map[string]intrinsic |
| |
| func init() { |
| // Key strings are from Function.String(). |
| // That little dot ۰ is an Arabic zero numeral (U+06F0), |
| // categories [Nd]. |
| intrinsicsByName = map[string]intrinsic{ |
| // reflect.Value methods. |
| // "(reflect.Value).Addr": ext۰reflect۰Value۰Addr, |
| "(reflect.Value).Bool": ext۰NoEffect, |
| // "(reflect.Value).Bytes": ext۰reflect۰Value۰Bytes, |
| // "(reflect.Value).Call": ext۰reflect۰Value۰Call, |
| // "(reflect.Value).CallSlice": ext۰reflect۰Value۰CallSlice, |
| "(reflect.Value).CanAddr": ext۰NoEffect, |
| "(reflect.Value).CanInterface": ext۰NoEffect, |
| "(reflect.Value).CanSet": ext۰NoEffect, |
| "(reflect.Value).Cap": ext۰NoEffect, |
| "(reflect.Value).Close": ext۰NoEffect, |
| "(reflect.Value).Complex": ext۰NoEffect, |
| // "(reflect.Value).Convert": ext۰reflect۰Value۰Convert, |
| // "(reflect.Value).Elem": ext۰reflect۰Value۰Elem, |
| // "(reflect.Value).Field": ext۰reflect۰Value۰Field, |
| // "(reflect.Value).FieldByIndex": ext۰reflect۰Value۰FieldByIndex, |
| // "(reflect.Value).FieldByName": ext۰reflect۰Value۰FieldByName, |
| // "(reflect.Value).FieldByNameFunc": ext۰reflect۰Value۰FieldByNameFunc, |
| "(reflect.Value).Float": ext۰NoEffect, |
| // "(reflect.Value).Index": ext۰reflect۰Value۰Index, |
| "(reflect.Value).Int": ext۰NoEffect, |
| // "(reflect.Value).Interface": ext۰reflect۰Value۰Interface, |
| "(reflect.Value).InterfaceData": ext۰NoEffect, |
| "(reflect.Value).IsNil": ext۰NoEffect, |
| "(reflect.Value).IsValid": ext۰NoEffect, |
| "(reflect.Value).Kind": ext۰NoEffect, |
| "(reflect.Value).Len": ext۰NoEffect, |
| // "(reflect.Value).MapIndex": ext۰reflect۰Value۰MapIndex, |
| // "(reflect.Value).MapKeys": ext۰reflect۰Value۰MapKeys, |
| // "(reflect.Value).Method": ext۰reflect۰Value۰Method, |
| // "(reflect.Value).MethodByName": ext۰reflect۰Value۰MethodByName, |
| "(reflect.Value).NumField": ext۰NoEffect, |
| "(reflect.Value).NumMethod": ext۰NoEffect, |
| "(reflect.Value).OverflowComplex": ext۰NoEffect, |
| "(reflect.Value).OverflowFloat": ext۰NoEffect, |
| "(reflect.Value).OverflowInt": ext۰NoEffect, |
| "(reflect.Value).OverflowUint": ext۰NoEffect, |
| "(reflect.Value).Pointer": ext۰NoEffect, |
| // "(reflect.Value).Set": ext۰reflect۰Value۰Set, |
| "(reflect.Value).SetBool": ext۰NoEffect, |
| // "(reflect.Value).SetBytes": ext۰reflect۰Value۰SetBytes, |
| "(reflect.Value).SetComplex": ext۰NoEffect, |
| "(reflect.Value).SetFloat": ext۰NoEffect, |
| "(reflect.Value).SetInt": ext۰NoEffect, |
| "(reflect.Value).SetLen": ext۰NoEffect, |
| // "(reflect.Value).SetMapIndex": ext۰reflect۰Value۰SetMapIndex, |
| // "(reflect.Value).SetPointer": ext۰reflect۰Value۰SetPointer, |
| "(reflect.Value).SetString": ext۰NoEffect, |
| "(reflect.Value).SetUint": ext۰NoEffect, |
| // "(reflect.Value).Slice": ext۰reflect۰Value۰Slice, |
| "(reflect.Value).String": ext۰NoEffect, |
| "(reflect.Value).Type": ext۰NoEffect, |
| "(reflect.Value).Uint": ext۰NoEffect, |
| "(reflect.Value).UnsafeAddr": ext۰NoEffect, |
| |
| // Standalone reflect.* functions. |
| "reflect.Append": ext۰NotYetImplemented, |
| "reflect.AppendSlice": ext۰NotYetImplemented, |
| "reflect.Copy": ext۰NotYetImplemented, |
| // "reflect.ChanOf": ext۰reflect۰ChanOf, |
| "reflect.DeepEqual": ext۰NoEffect, |
| // "reflect.Indirect": ext۰reflect۰Indirect, |
| // "reflect.MakeChan": ext۰reflect۰MakeChan, |
| "reflect.MakeFunc": ext۰NotYetImplemented, |
| "reflect.MakeMap": ext۰NotYetImplemented, |
| "reflect.MakeSlice": ext۰NotYetImplemented, |
| "reflect.MapOf": ext۰NotYetImplemented, |
| // "reflect.New": ext۰reflect۰New, |
| // "reflect.NewAt": ext۰reflect۰NewAt, |
| "reflect.PtrTo": ext۰NotYetImplemented, |
| "reflect.Select": ext۰NotYetImplemented, |
| "reflect.SliceOf": ext۰NotYetImplemented, |
| // "reflect.TypeOf": ext۰reflect۰TypeOf, |
| // "reflect.ValueOf": ext۰reflect۰ValueOf, |
| // "reflect.Zero": ext۰reflect۰Zero, |
| "reflect.init": ext۰NoEffect, |
| |
| // *reflect.rtype methods |
| "(*reflect.rtype).Align": ext۰NoEffect, |
| "(*reflect.rtype).AssignableTo": ext۰NoEffect, |
| "(*reflect.rtype).Bits": ext۰NoEffect, |
| "(*reflect.rtype).ChanDir": ext۰NoEffect, |
| "(*reflect.rtype).ConvertibleTo": ext۰NoEffect, |
| // "(*reflect.rtype).Elem": ext۰reflect۰rtype۰Elem, |
| "(*reflect.rtype).Field": ext۰NotYetImplemented, |
| "(*reflect.rtype).FieldAlign": ext۰NoEffect, |
| // "(*reflect.rtype).FieldByIndex": ext۰reflect۰rtype۰FieldByIndex, |
| // "(*reflect.rtype).FieldByName": ext۰reflect۰rtype۰FieldByName, |
| // "(*reflect.rtype).FieldByNameFunc": ext۰reflect۰rtype۰FieldByNameFunc, |
| "(*reflect.rtype).Implements": ext۰NoEffect, |
| // "(*reflect.rtype).In": ext۰reflect۰rtype۰In, |
| "(*reflect.rtype).IsVariadic": ext۰NoEffect, |
| // "(*reflect.rtype).Key": ext۰reflect۰rtype۰Key, |
| "(*reflect.rtype).Kind": ext۰NoEffect, |
| "(*reflect.rtype).Len": ext۰NoEffect, |
| "(*reflect.rtype).Method": ext۰NotYetImplemented, |
| "(*reflect.rtype).MethodByName": ext۰NotYetImplemented, |
| "(*reflect.rtype).Name": ext۰NoEffect, |
| "(*reflect.rtype).NumField": ext۰NoEffect, |
| "(*reflect.rtype).NumIn": ext۰NoEffect, |
| "(*reflect.rtype).NumMethod": ext۰NoEffect, |
| "(*reflect.rtype).NumOut": ext۰NoEffect, |
| // "(*reflect.rtype).Out": ext۰reflect۰rtype۰Out, |
| "(*reflect.rtype).PkgPath": ext۰NoEffect, |
| "(*reflect.rtype).Size": ext۰NoEffect, |
| "(*reflect.rtype).String": ext۰NoEffect, |
| |
| // Other packages. |
| "bytes.Equal": ext۰NoEffect, |
| "bytes.IndexByte": ext۰NoEffect, |
| "crypto/aes.decryptBlockAsm": ext۰NoEffect, |
| "crypto/aes.encryptBlockAsm": ext۰NoEffect, |
| "crypto/aes.expandKeyAsm": ext۰NoEffect, |
| "crypto/aes.hasAsm": ext۰NoEffect, |
| "crypto/md5.block": ext۰NoEffect, |
| "crypto/rc4.xorKeyStream": ext۰NoEffect, |
| "crypto/sha1.block": ext۰NoEffect, |
| "hash/crc32.castagnoliSSE42": ext۰NoEffect, |
| "hash/crc32.haveSSE42": ext۰NoEffect, |
| "math.Abs": ext۰NoEffect, |
| "math.Acos": ext۰NoEffect, |
| "math.Asin": ext۰NoEffect, |
| "math.Atan": ext۰NoEffect, |
| "math.Atan2": ext۰NoEffect, |
| "math.Ceil": ext۰NoEffect, |
| "math.Cos": ext۰NoEffect, |
| "math.Dim": ext۰NoEffect, |
| "math.Exp": ext۰NoEffect, |
| "math.Exp2": ext۰NoEffect, |
| "math.Expm1": ext۰NoEffect, |
| "math.Float32bits": ext۰NoEffect, |
| "math.Float32frombits": ext۰NoEffect, |
| "math.Float64bits": ext۰NoEffect, |
| "math.Float64frombits": ext۰NoEffect, |
| "math.Floor": ext۰NoEffect, |
| "math.Frexp": ext۰NoEffect, |
| "math.Hypot": ext۰NoEffect, |
| "math.Ldexp": ext۰NoEffect, |
| "math.Log": ext۰NoEffect, |
| "math.Log10": ext۰NoEffect, |
| "math.Log1p": ext۰NoEffect, |
| "math.Log2": ext۰NoEffect, |
| "math.Max": ext۰NoEffect, |
| "math.Min": ext۰NoEffect, |
| "math.Mod": ext۰NoEffect, |
| "math.Modf": ext۰NoEffect, |
| "math.Remainder": ext۰NoEffect, |
| "math.Sin": ext۰NoEffect, |
| "math.Sincos": ext۰NoEffect, |
| "math.Sqrt": ext۰NoEffect, |
| "math.Tan": ext۰NoEffect, |
| "math.Trunc": ext۰NoEffect, |
| "math/big.addMulVVW": ext۰NoEffect, |
| "math/big.addVV": ext۰NoEffect, |
| "math/big.addVW": ext۰NoEffect, |
| "math/big.bitLen": ext۰NoEffect, |
| "math/big.divWVW": ext۰NoEffect, |
| "math/big.divWW": ext۰NoEffect, |
| "math/big.mulAddVWW": ext۰NoEffect, |
| "math/big.mulWW": ext۰NoEffect, |
| "math/big.shlVU": ext۰NoEffect, |
| "math/big.shrVU": ext۰NoEffect, |
| "math/big.subVV": ext۰NoEffect, |
| "math/big.subVW": ext۰NoEffect, |
| "net.runtime_Semacquire": ext۰NoEffect, |
| "net.runtime_Semrelease": ext۰NoEffect, |
| "net.runtime_pollClose": ext۰NoEffect, |
| "net.runtime_pollOpen": ext۰NoEffect, |
| "net.runtime_pollReset": ext۰NoEffect, |
| "net.runtime_pollServerInit": ext۰NoEffect, |
| "net.runtime_pollSetDeadline": ext۰NoEffect, |
| "net.runtime_pollUnblock": ext۰NoEffect, |
| "net.runtime_pollWait": ext۰NoEffect, |
| "os.epipecheck": ext۰NoEffect, |
| "runtime.BlockProfile": ext۰NoEffect, |
| "runtime.Breakpoint": ext۰NoEffect, |
| "runtime.CPUProfile": ext۰NotYetImplemented, |
| "runtime.Caller": ext۰NoEffect, |
| "runtime.FuncForPC": ext۰NotYetImplemented, |
| "runtime.GC": ext۰NoEffect, |
| "runtime.GOMAXPROCS": ext۰NoEffect, |
| "runtime.Goexit": ext۰NoEffect, |
| "runtime.GoroutineProfile": ext۰NoEffect, |
| "runtime.Gosched": ext۰NoEffect, |
| "runtime.MemProfile": ext۰NoEffect, |
| "runtime.NumCPU": ext۰NoEffect, |
| "runtime.NumGoroutine": ext۰NoEffect, |
| "runtime.ReadMemStats": ext۰NoEffect, |
| "runtime.SetBlockProfileRate": ext۰NoEffect, |
| "runtime.SetCPUProfileRate": ext۰NoEffect, |
| "runtime.SetFinalizer": ext۰NotYetImplemented, |
| "runtime.Stack": ext۰NoEffect, |
| "runtime.ThreadCreateProfile": ext۰NoEffect, |
| "runtime.funcentry_go": ext۰NoEffect, |
| "runtime.funcline_go": ext۰NoEffect, |
| "runtime.funcname_go": ext۰NoEffect, |
| "runtime.getgoroot": ext۰NoEffect, |
| "runtime/pprof.runtime_cyclesPerSecond": ext۰NoEffect, |
| "strings.IndexByte": ext۰NoEffect, |
| "sync.runtime_Semacquire": ext۰NoEffect, |
| "sync.runtime_Semrelease": ext۰NoEffect, |
| "sync.runtime_Syncsemacquire": ext۰NoEffect, |
| "sync.runtime_Syncsemcheck": ext۰NoEffect, |
| "sync.runtime_Syncsemrelease": ext۰NoEffect, |
| "sync/atomic.AddInt32": ext۰NoEffect, |
| "sync/atomic.AddUint32": ext۰NoEffect, |
| "sync/atomic.CompareAndSwapInt32": ext۰NoEffect, |
| "sync/atomic.CompareAndSwapUint32": ext۰NoEffect, |
| "sync/atomic.CompareAndSwapUint64": ext۰NoEffect, |
| "sync/atomic.CompareAndSwapUintptr": ext۰NoEffect, |
| "sync/atomic.LoadInt32": ext۰NoEffect, |
| "sync/atomic.LoadUint32": ext۰NoEffect, |
| "sync/atomic.LoadUint64": ext۰NoEffect, |
| "sync/atomic.StoreInt32": ext۰NoEffect, |
| "sync/atomic.StoreUint32": ext۰NoEffect, |
| "syscall.Close": ext۰NoEffect, |
| "syscall.Exit": ext۰NoEffect, |
| "syscall.Getpid": ext۰NoEffect, |
| "syscall.Getwd": ext۰NoEffect, |
| "syscall.Kill": ext۰NoEffect, |
| "syscall.RawSyscall": ext۰NoEffect, |
| "syscall.RawSyscall6": ext۰NoEffect, |
| "syscall.Syscall": ext۰NoEffect, |
| "syscall.Syscall6": ext۰NoEffect, |
| "syscall.runtime_AfterFork": ext۰NoEffect, |
| "syscall.runtime_BeforeFork": ext۰NoEffect, |
| "time.Sleep": ext۰NoEffect, |
| "time.now": ext۰NoEffect, |
| "time.startTimer": ext۰NoEffect, |
| "time.stopTimer": ext۰NoEffect, |
| } |
| } |
| |
| // findIntrinsic returns the constraint generation function for an |
| // intrinsic function fn, or nil if the function should be handled normally. |
| // |
| func (a *analysis) findIntrinsic(fn *ssa.Function) intrinsic { |
| // Consult the *Function-keyed cache. |
| // A cached nil indicates a normal non-intrinsic function. |
| impl, ok := a.intrinsics[fn] |
| if !ok { |
| impl = intrinsicsByName[fn.String()] // may be nil |
| |
| // Ensure all "reflect" code is treated intrinsically. |
| if impl == nil && fn.Pkg != nil && a.reflectValueObj != nil && a.reflectValueObj.Pkg() == fn.Pkg.Object { |
| impl = ext۰NotYetImplemented |
| } |
| |
| a.intrinsics[fn] = impl |
| } |
| return impl |
| } |
| |
| // 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 |
| // 3) create any labels. |
| // |
| // Many intrinsics (such as CompareAndSwapInt32) have a fourth kind of |
| // 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 |
| // 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. |
| // a.warnf(fn.Pos(), "unsound: intrinsic treatment of %s not yet implemented", fn) |
| } |
| |
| // We'll model reflect.Value as an interface{} containing pointers. |
| // We must use pointers since some reflect.Values (those derived by |
| // Field, Elem, etc) are abstractions of lvalues, not rvalues, and |
| // mutations via Set are reflected in the underlying value. (We could |
| // represent it as a union of lvalue and rvalue but that's more work.) |
