// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
-package gc
+package pkginit
import (
"bytes"
"container/heap"
"fmt"
+
+ "cmd/compile/internal/base"
+ "cmd/compile/internal/ir"
+ "cmd/compile/internal/staticinit"
)
// Package initialization
type InitOrder struct {
// blocking maps initialization assignments to the assignments
// that depend on it.
- blocking map[*Node][]*Node
+ blocking map[ir.Node][]ir.Node
// ready is the queue of Pending initialization assignments
// that are ready for initialization.
ready declOrder
+
+ order map[ir.Node]int
}
// initOrder computes initialization order for a list l of
// package-level declarations (in declaration order) and outputs the
// corresponding list of statements to include in the init() function
// body.
-func initOrder(l []*Node) []*Node {
- s := InitSchedule{
- initplans: make(map[*Node]*InitPlan),
- inittemps: make(map[*Node]*Node),
+func initOrder(l []ir.Node) []ir.Node {
+ s := staticinit.Schedule{
+ Plans: make(map[ir.Node]*staticinit.Plan),
+ Temps: make(map[ir.Node]*ir.Name),
}
o := InitOrder{
- blocking: make(map[*Node][]*Node),
+ blocking: make(map[ir.Node][]ir.Node),
+ order: make(map[ir.Node]int),
}
// Process all package-level assignment in declaration order.
for _, n := range l {
- switch n.Op {
- case OAS, OAS2DOTTYPE, OAS2FUNC, OAS2MAPR, OAS2RECV:
+ switch n.Op() {
+ case ir.OAS, ir.OAS2DOTTYPE, ir.OAS2FUNC, ir.OAS2MAPR, ir.OAS2RECV:
o.processAssign(n)
- o.flushReady(s.staticInit)
- case ODCLCONST, ODCLFUNC, ODCLTYPE:
+ o.flushReady(s.StaticInit)
+ case ir.ODCLCONST, ir.ODCLFUNC, ir.ODCLTYPE:
// nop
default:
- Fatalf("unexpected package-level statement: %v", n)
+ base.Fatalf("unexpected package-level statement: %v", n)
}
}
// Check that all assignments are now Done; if not, there must
// have been a dependency cycle.
for _, n := range l {
- switch n.Op {
- case OAS, OAS2DOTTYPE, OAS2FUNC, OAS2MAPR, OAS2RECV:
- if n.Initorder() != InitDone {
+ switch n.Op() {
+ case ir.OAS, ir.OAS2DOTTYPE, ir.OAS2FUNC, ir.OAS2MAPR, ir.OAS2RECV:
+ if o.order[n] != orderDone {
// If there have already been errors
// printed, those errors may have
// confused us and there might not be
// a loop. Let the user fix those
// first.
- if nerrors > 0 {
- errorexit()
- }
+ base.ExitIfErrors()
- findInitLoopAndExit(firstLHS(n), new([]*Node), make(map[*Node]bool))
- Fatalf("initialization unfinished, but failed to identify loop")
+ o.findInitLoopAndExit(firstLHS(n), new([]*ir.Name), new(ir.NameSet))
+ base.Fatalf("initialization unfinished, but failed to identify loop")
}
}
}
// Invariant consistency check. If this is non-zero, then we
// should have found a cycle above.
if len(o.blocking) != 0 {
- Fatalf("expected empty map: %v", o.blocking)
+ base.Fatalf("expected empty map: %v", o.blocking)
}
- return s.out
+ return s.Out
}
-func (o *InitOrder) processAssign(n *Node) {
- if n.Initorder() != InitNotStarted || n.Xoffset != BADWIDTH {
- Fatalf("unexpected state: %v, %v, %v", n, n.Initorder(), n.Xoffset)
+func (o *InitOrder) processAssign(n ir.Node) {
+ if _, ok := o.order[n]; ok {
+ base.Fatalf("unexpected state: %v, %v", n, o.order[n])
}
-
- n.SetInitorder(InitPending)
- n.Xoffset = 0
+ o.order[n] = 0
// Compute number of variable dependencies and build the
// inverse dependency ("blocking") graph.
for dep := range collectDeps(n, true) {
- defn := dep.Name.Defn
+ defn := dep.Defn
// Skip dependencies on functions (PFUNC) and
// variables already initialized (InitDone).
- if dep.Class() != PEXTERN || defn.Initorder() == InitDone {
+ if dep.Class != ir.PEXTERN || o.order[defn] == orderDone {
continue
}
- n.Xoffset++
+ o.order[n]++
o.blocking[defn] = append(o.blocking[defn], n)
}
- if n.Xoffset == 0 {
+ if o.order[n] == 0 {
heap.Push(&o.ready, n)
}
}
+const orderDone = -1000
+
// flushReady repeatedly applies initialize to the earliest (in
// declaration order) assignment ready for initialization and updates
// the inverse dependency ("blocking") graph.
-func (o *InitOrder) flushReady(initialize func(*Node)) {
+func (o *InitOrder) flushReady(initialize func(ir.Node)) {
for o.ready.Len() != 0 {
- n := heap.Pop(&o.ready).(*Node)
- if n.Initorder() != InitPending || n.Xoffset != 0 {
- Fatalf("unexpected state: %v, %v, %v", n, n.Initorder(), n.Xoffset)
+ n := heap.Pop(&o.ready).(ir.Node)
+ if order, ok := o.order[n]; !ok || order != 0 {
+ base.Fatalf("unexpected state: %v, %v, %v", n, ok, order)
}
initialize(n)
- n.SetInitorder(InitDone)
- n.Xoffset = BADWIDTH
+ o.order[n] = orderDone
blocked := o.blocking[n]
delete(o.blocking, n)
for _, m := range blocked {
- m.Xoffset--
- if m.Xoffset == 0 {
+ if o.order[m]--; o.order[m] == 0 {
heap.Push(&o.ready, m)
}
}
// path points to a slice used for tracking the sequence of
// variables/functions visited. Using a pointer to a slice allows the
// slice capacity to grow and limit reallocations.
-func findInitLoopAndExit(n *Node, path *[]*Node, ok map[*Node]bool) {
+func (o *InitOrder) findInitLoopAndExit(n *ir.Name, path *[]*ir.Name, ok *ir.NameSet) {
for i, x := range *path {
if x == n {
reportInitLoopAndExit((*path)[i:])
// There might be multiple loops involving n; by sorting
// references, we deterministically pick the one reported.
- refers := collectDeps(n.Name.Defn, false).Sorted(func(ni, nj *Node) bool {
- return ni.Pos.Before(nj.Pos)
+ refers := collectDeps(n.Defn, false).Sorted(func(ni, nj *ir.Name) bool {
+ return ni.Pos().Before(nj.Pos())
})
*path = append(*path, n)
for _, ref := range refers {
// Short-circuit variables that were initialized.
- if ref.Class() == PEXTERN && ref.Name.Defn.Initorder() == InitDone || ok[ref] {
+ if ref.Class == ir.PEXTERN && o.order[ref.Defn] == orderDone || ok.Has(ref) {
continue
}
- findInitLoopAndExit(ref, path, ok)
+
+ o.findInitLoopAndExit(ref, path, ok)
}
// n is not involved in a cycle.
// Record that fact to avoid checking it again when reached another way,
// or else this traversal will take exponential time traversing all paths
// through the part of the package's call graph implicated in the cycle.
- ok[n] = true
+ ok.Add(n)
*path = (*path)[:len(*path)-1]
}
// reportInitLoopAndExit reports and initialization loop as an error
// and exits. However, if l is not actually an initialization loop, it
// simply returns instead.
-func reportInitLoopAndExit(l []*Node) {
+func reportInitLoopAndExit(l []*ir.Name) {
// Rotate loop so that the earliest variable declaration is at
// the start.
i := -1
for j, n := range l {
- if n.Class() == PEXTERN && (i == -1 || n.Pos.Before(l[i].Pos)) {
+ if n.Class == ir.PEXTERN && (i == -1 || n.Pos().Before(l[i].Pos())) {
i = j
}
}
var msg bytes.Buffer
fmt.Fprintf(&msg, "initialization loop:\n")
for _, n := range l {
- fmt.Fprintf(&msg, "\t%v: %v refers to\n", n.Line(), n)
+ fmt.Fprintf(&msg, "\t%v: %v refers to\n", ir.Line(n), n)
}
- fmt.Fprintf(&msg, "\t%v: %v", l[0].Line(), l[0])
+ fmt.Fprintf(&msg, "\t%v: %v", ir.Line(l[0]), l[0])
- yyerrorl(l[0].Pos, msg.String())
- errorexit()
+ base.ErrorfAt(l[0].Pos(), msg.String())
+ base.ErrorExit()
}
// collectDeps returns all of the package-level functions and
// variables that declaration n depends on. If transitive is true,
// then it also includes the transitive dependencies of any depended
// upon functions (but not variables).
-func collectDeps(n *Node, transitive bool) NodeSet {
+func collectDeps(n ir.Node, transitive bool) ir.NameSet {
d := initDeps{transitive: transitive}
- switch n.Op {
- case OAS:
- d.inspect(n.Right)
- case OAS2DOTTYPE, OAS2FUNC, OAS2MAPR, OAS2RECV:
- d.inspect(n.Right)
- case ODCLFUNC:
- d.inspectList(n.Nbody)
+ switch n.Op() {
+ case ir.OAS:
+ n := n.(*ir.AssignStmt)
+ d.inspect(n.Y)
+ case ir.OAS2DOTTYPE, ir.OAS2FUNC, ir.OAS2MAPR, ir.OAS2RECV:
+ n := n.(*ir.AssignListStmt)
+ d.inspect(n.Rhs[0])
+ case ir.ODCLFUNC:
+ n := n.(*ir.Func)
+ d.inspectList(n.Body)
default:
- Fatalf("unexpected Op: %v", n.Op)
+ base.Fatalf("unexpected Op: %v", n.Op())
}
return d.seen
}
type initDeps struct {
transitive bool
- seen NodeSet
+ seen ir.NameSet
+ cvisit func(ir.Node)
+}
+
+func (d *initDeps) cachedVisit() func(ir.Node) {
+ if d.cvisit == nil {
+ d.cvisit = d.visit // cache closure
+ }
+ return d.cvisit
}
-func (d *initDeps) inspect(n *Node) { inspect(n, d.visit) }
-func (d *initDeps) inspectList(l Nodes) { inspectList(l, d.visit) }
+func (d *initDeps) inspect(n ir.Node) { ir.Visit(n, d.cachedVisit()) }
+func (d *initDeps) inspectList(l ir.Nodes) { ir.VisitList(l, d.cachedVisit()) }
// visit calls foundDep on any package-level functions or variables
// referenced by n, if any.
-func (d *initDeps) visit(n *Node) bool {
- switch n.Op {
- case ONAME:
- if n.isMethodExpression() {
- d.foundDep(asNode(n.Type.FuncType().Nname))
- return false
- }
-
- switch n.Class() {
- case PEXTERN, PFUNC:
+func (d *initDeps) visit(n ir.Node) {
+ switch n.Op() {
+ case ir.ONAME:
+ n := n.(*ir.Name)
+ switch n.Class {
+ case ir.PEXTERN, ir.PFUNC:
d.foundDep(n)
}
- case OCLOSURE:
- d.inspectList(n.Func.Closure.Nbody)
+ case ir.OCLOSURE:
+ n := n.(*ir.ClosureExpr)
+ d.inspectList(n.Func.Body)
- case ODOTMETH, OCALLPART:
- d.foundDep(asNode(n.Type.FuncType().Nname))
+ case ir.ODOTMETH, ir.OCALLPART, ir.OMETHEXPR:
+ d.foundDep(ir.MethodExprName(n))
}
-
- return true
}
// foundDep records that we've found a dependency on n by adding it to
// seen.
-func (d *initDeps) foundDep(n *Node) {
+func (d *initDeps) foundDep(n *ir.Name) {
// Can happen with method expressions involving interface
// types; e.g., fixedbugs/issue4495.go.
if n == nil {
// Names without definitions aren't interesting as far as
// initialization ordering goes.
- if n.Name.Defn == nil {
+ if n.Defn == nil {
return
}
return
}
d.seen.Add(n)
- if d.transitive && n.Class() == PFUNC {
- d.inspectList(n.Name.Defn.Nbody)
+ if d.transitive && n.Class == ir.PFUNC {
+ d.inspectList(n.Defn.(*ir.Func).Body)
}
}
// an OAS node's Pos may not be unique. For example, given the
// declaration "var a, b = f(), g()", "a" must be ordered before "b",
// but both OAS nodes use the "=" token's position as their Pos.
-type declOrder []*Node
+type declOrder []ir.Node
-func (s declOrder) Len() int { return len(s) }
-func (s declOrder) Less(i, j int) bool { return firstLHS(s[i]).Pos.Before(firstLHS(s[j]).Pos) }
-func (s declOrder) Swap(i, j int) { s[i], s[j] = s[j], s[i] }
+func (s declOrder) Len() int { return len(s) }
+func (s declOrder) Less(i, j int) bool {
+ return firstLHS(s[i]).Pos().Before(firstLHS(s[j]).Pos())
+}
+func (s declOrder) Swap(i, j int) { s[i], s[j] = s[j], s[i] }
-func (s *declOrder) Push(x interface{}) { *s = append(*s, x.(*Node)) }
+func (s *declOrder) Push(x interface{}) { *s = append(*s, x.(ir.Node)) }
func (s *declOrder) Pop() interface{} {
n := (*s)[len(*s)-1]
*s = (*s)[:len(*s)-1]
// firstLHS returns the first expression on the left-hand side of
// assignment n.
-func firstLHS(n *Node) *Node {
- switch n.Op {
- case OAS:
- return n.Left
- case OAS2DOTTYPE, OAS2FUNC, OAS2RECV, OAS2MAPR:
- return n.List.First()
+func firstLHS(n ir.Node) *ir.Name {
+ switch n.Op() {
+ case ir.OAS:
+ n := n.(*ir.AssignStmt)
+ return n.X.Name()
+ case ir.OAS2DOTTYPE, ir.OAS2FUNC, ir.OAS2RECV, ir.OAS2MAPR:
+ n := n.(*ir.AssignListStmt)
+ return n.Lhs[0].Name()
}
- Fatalf("unexpected Op: %v", n.Op)
+ base.Fatalf("unexpected Op: %v", n.Op())
return nil
}