// generate generates offline constraints for the entire program.
func (a *analysis) generate() {
start("Constraint generation")
if a.log != nil {
fmt.Fprintln(a.log, "==== Generating constraints")
}
// Create a dummy node since we use the nodeid 0 for
// non-pointerlike variables.
a.addNodes(tInvalid, "(zero)")
// Create the global node for panic values.
a.panicNode = a.addNodes(tEface, "panic")
// Create nodes and constraints for all methods of reflect.rtype.
// (Shared contours are used by dynamic calls to reflect.Type
// methods---typically just String().)
if rtype := a.reflectRtypePtr; rtype != nil {
a.genMethodsOf(rtype)
}
root := a.genRootCalls()
if a.config.BuildCallGraph {
a.result.CallGraph = callgraph.New(root.fn)
}
// Create nodes and constraints for all methods of all types
// that are dynamically accessible via reflection or interfaces.
for _, T := range a.prog.TypesWithMethodSets() {
a.genMethodsOf(T)
}
// Generate constraints for entire program.
for len(a.genq) > 0 {
cgn := a.genq[0]
a.genq = a.genq[1:]
a.genFunc(cgn)
}
// The runtime magically allocates os.Args; so should we.
if os := a.prog.ImportedPackage("os"); os != nil {
// In effect: os.Args = new([1]string)[:]
T := types.NewSlice(types.Typ[types.String])
obj := a.addNodes(sliceToArray(T), "<command-line args>")
a.endObject(obj, nil, "<command-line args>")
a.addressOf(T, a.objectNode(nil, os.Var("Args")), obj)
}
// Discard generation state, to avoid confusion after node renumbering.
a.panicNode = 0
a.globalval = nil
a.localval = nil
a.localobj = nil
stop("Constraint generation")
}
// createParams creates parameters for wrapper method fn based on its
// Signature.Params, which do not include the receiver.
// start is the index of the first regular parameter to use.
//
func createParams(fn *Function, start int) {
var last *Parameter
tparams := fn.Signature.Params()
for i, n := start, tparams.Len(); i < n; i++ {
last = fn.addParamObj(tparams.At(i))
}
if fn.Signature.Variadic() {
last.typ = types.NewSlice(last.typ)
}
}
// Type =
// BasicType | TypeName | ArrayType | SliceType | StructType |
// PointerType | FuncType | InterfaceType | MapType | ChanType |
// "(" Type ")" .
//
// BasicType = ident .
// TypeName = ExportedName .
// SliceType = "[" "]" Type .
// PointerType = "*" Type .
// FuncType = "func" Signature .
//
func (p *parser) parseType() types.Type {
switch p.tok {
case scanner.Ident:
switch p.lit {
default:
return p.parseBasicType()
case "struct":
return p.parseStructType()
case "func":
// FuncType
p.next()
return p.parseSignature(nil)
case "interface":
return p.parseInterfaceType()
case "map":
return p.parseMapType()
case "chan":
return p.parseChanType()
}
case '@':
// TypeName
pkg, name := p.parseExportedName()
return declTypeName(pkg, name).Type()
case '[':
p.next() // look ahead
if p.tok == ']' {
// SliceType
p.next()
return types.NewSlice(p.parseType())
}
return p.parseArrayType()
case '*':
// PointerType
p.next()
return types.NewPointer(p.parseType())
case '<':
return p.parseChanType()
case '(':
// "(" Type ")"
p.next()
typ := p.parseType()
p.expect(')')
return typ
}
p.errorf("expected type, got %s (%q)", scanner.TokenString(p.tok), p.lit)
return nil
}
// Parameter = ( identifier | "?" ) [ "..." ] Type [ string_lit ] .
//
func (p *parser) parseParameter() (par *types.Var, isVariadic bool) {
_, name := p.parseName(false)
// remove gc-specific parameter numbering
if i := strings.Index(name, "·"); i >= 0 {
name = name[:i]
}
if p.tok == '.' {
p.expectSpecial("...")
isVariadic = true
}
typ := p.parseType()
if isVariadic {
typ = types.NewSlice(typ)
}
// ignore argument tag (e.g. "noescape")
if p.tok == scanner.String {
p.next()
}
// TODO(gri) should we provide a package?
par = types.NewVar(token.NoPos, nil, name, typ)
return
}