blob: 5eca6e01817e185bdb870471cc8ef6857164db4f [file] [log] [blame]
// Copyright 2016 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 ld
import (
"cmd/internal/objabi"
"cmd/link/internal/loader"
"cmd/link/internal/sym"
"sort"
)
type byTypeStr []typelinkSortKey
type typelinkSortKey struct {
TypeStr string
Type loader.Sym
}
func (s byTypeStr) Less(i, j int) bool { return s[i].TypeStr < s[j].TypeStr }
func (s byTypeStr) Len() int { return len(s) }
func (s byTypeStr) Swap(i, j int) { s[i], s[j] = s[j], s[i] }
// typelink generates the typelink table which is used by reflect.typelinks().
// Types that should be added to the typelinks table are marked with the
// MakeTypelink attribute by the compiler.
func (ctxt *Link) typelink() {
ldr := ctxt.loader
typelinks := byTypeStr{}
var itabs []loader.Sym
for s := loader.Sym(1); s < loader.Sym(ldr.NSym()); s++ {
if !ldr.AttrReachable(s) {
continue
}
if ldr.IsTypelink(s) {
typelinks = append(typelinks, typelinkSortKey{decodetypeStr(ldr, ctxt.Arch, s), s})
} else if ldr.IsItab(s) {
itabs = append(itabs, s)
}
}
sort.Sort(typelinks)
tl := ldr.CreateSymForUpdate("runtime.typelink", 0)
tl.SetType(sym.STYPELINK)
ldr.SetAttrLocal(tl.Sym(), true)
tl.SetSize(int64(4 * len(typelinks)))
tl.Grow(tl.Size())
relocs := tl.AddRelocs(len(typelinks))
for i, s := range typelinks {
r := relocs.At(i)
r.SetSym(s.Type)
r.SetOff(int32(i * 4))
r.SetSiz(4)
r.SetType(objabi.R_ADDROFF)
}
ptrsize := ctxt.Arch.PtrSize
il := ldr.CreateSymForUpdate("runtime.itablink", 0)
il.SetType(sym.SITABLINK)
ldr.SetAttrLocal(il.Sym(), true)
il.SetSize(int64(ptrsize * len(itabs)))
il.Grow(il.Size())
relocs = il.AddRelocs(len(itabs))
for i, s := range itabs {
r := relocs.At(i)
r.SetSym(s)
r.SetOff(int32(i * ptrsize))
r.SetSiz(uint8(ptrsize))
r.SetType(objabi.R_ADDR)
}
}