You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
71 lines
1.5 KiB
71 lines
1.5 KiB
package analysis
|
|
|
|
import (
|
|
"go/ast"
|
|
"go/token"
|
|
"go/types"
|
|
)
|
|
|
|
func EscapingObjects(n ast.Node, info *types.Info) []*types.Var {
|
|
v := escapeAnalysis{
|
|
info: info,
|
|
escaping: make(map[*types.Var]bool),
|
|
topScope: info.Scopes[n],
|
|
bottomScopes: make(map[*types.Scope]bool),
|
|
}
|
|
ast.Walk(&v, n)
|
|
var list []*types.Var
|
|
for obj := range v.escaping {
|
|
list = append(list, obj)
|
|
}
|
|
return list
|
|
}
|
|
|
|
type escapeAnalysis struct {
|
|
info *types.Info
|
|
escaping map[*types.Var]bool
|
|
topScope *types.Scope
|
|
bottomScopes map[*types.Scope]bool
|
|
}
|
|
|
|
func (v *escapeAnalysis) Visit(node ast.Node) (w ast.Visitor) {
|
|
// huge overapproximation
|
|
switch n := node.(type) {
|
|
case *ast.UnaryExpr:
|
|
if n.Op == token.AND {
|
|
if _, ok := n.X.(*ast.Ident); ok {
|
|
return &escapingObjectCollector{v}
|
|
}
|
|
}
|
|
case *ast.FuncLit:
|
|
v.bottomScopes[v.info.Scopes[n.Type]] = true
|
|
return &escapingObjectCollector{v}
|
|
case *ast.ForStmt:
|
|
v.bottomScopes[v.info.Scopes[n.Body]] = true
|
|
case *ast.RangeStmt:
|
|
v.bottomScopes[v.info.Scopes[n.Body]] = true
|
|
}
|
|
return v
|
|
}
|
|
|
|
type escapingObjectCollector struct {
|
|
analysis *escapeAnalysis
|
|
}
|
|
|
|
func (v *escapingObjectCollector) Visit(node ast.Node) (w ast.Visitor) {
|
|
if id, ok := node.(*ast.Ident); ok {
|
|
if obj, ok := v.analysis.info.Uses[id].(*types.Var); ok {
|
|
for s := obj.Parent(); s != nil; s = s.Parent() {
|
|
if s == v.analysis.topScope {
|
|
v.analysis.escaping[obj] = true
|
|
break
|
|
}
|
|
if v.analysis.bottomScopes[s] {
|
|
break
|
|
}
|
|
}
|
|
}
|
|
}
|
|
return v
|
|
}
|