Adding upstream version 1.16.10.upstream/1.16.10upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 426 insertions, 0 deletions

diff --git a/src/cmd/internal/obj/sym.go b/src/cmd/internal/obj/sym.go
new file mode 100644
index 0000000..4515bdd
--- /dev/null
+++ b/src/cmd/internal/obj/sym.go
@@ -0,0 +1,426 @@
+// Derived from Inferno utils/6l/obj.c and utils/6l/span.c
+// https://bitbucket.org/inferno-os/inferno-os/src/master/utils/6l/obj.c
+// https://bitbucket.org/inferno-os/inferno-os/src/master/utils/6l/span.c
+//
+//	Copyright © 1994-1999 Lucent Technologies Inc.  All rights reserved.
+//	Portions Copyright © 1995-1997 C H Forsyth (forsyth@terzarima.net)
+//	Portions Copyright © 1997-1999 Vita Nuova Limited
+//	Portions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com)
+//	Portions Copyright © 2004,2006 Bruce Ellis
+//	Portions Copyright © 2005-2007 C H Forsyth (forsyth@terzarima.net)
+//	Revisions Copyright © 2000-2007 Lucent Technologies Inc. and others
+//	Portions Copyright © 2009 The Go Authors. All rights reserved.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+
+package obj
+
+import (
+	"cmd/internal/goobj"
+	"cmd/internal/objabi"
+	"fmt"
+	"log"
+	"math"
+	"sort"
+	"strings"
+)
+
+func Linknew(arch *LinkArch) *Link {
+	ctxt := new(Link)
+	ctxt.hash = make(map[string]*LSym)
+	ctxt.funchash = make(map[string]*LSym)
+	ctxt.statichash = make(map[string]*LSym)
+	ctxt.Arch = arch
+	ctxt.Pathname = objabi.WorkingDir()
+
+	if err := ctxt.Headtype.Set(objabi.GOOS); err != nil {
+		log.Fatalf("unknown goos %s", objabi.GOOS)
+	}
+
+	ctxt.Flag_optimize = true
+	return ctxt
+}
+
+// LookupDerived looks up or creates the symbol with name name derived from symbol s.
+// The resulting symbol will be static iff s is.
+func (ctxt *Link) LookupDerived(s *LSym, name string) *LSym {
+	if s.Static() {
+		return ctxt.LookupStatic(name)
+	}
+	return ctxt.Lookup(name)
+}
+
+// LookupStatic looks up the static symbol with name name.
+// If it does not exist, it creates it.
+func (ctxt *Link) LookupStatic(name string) *LSym {
+	s := ctxt.statichash[name]
+	if s == nil {
+		s = &LSym{Name: name, Attribute: AttrStatic}
+		ctxt.statichash[name] = s
+	}
+	return s
+}
+
+// LookupABI looks up a symbol with the given ABI.
+// If it does not exist, it creates it.
+func (ctxt *Link) LookupABI(name string, abi ABI) *LSym {
+	return ctxt.LookupABIInit(name, abi, nil)
+}
+
+// LookupABI looks up a symbol with the given ABI.
+// If it does not exist, it creates it and
+// passes it to init for one-time initialization.
+func (ctxt *Link) LookupABIInit(name string, abi ABI, init func(s *LSym)) *LSym {
+	var hash map[string]*LSym
+	switch abi {
+	case ABI0:
+		hash = ctxt.hash
+	case ABIInternal:
+		hash = ctxt.funchash
+	default:
+		panic("unknown ABI")
+	}
+
+	ctxt.hashmu.Lock()
+	s := hash[name]
+	if s == nil {
+		s = &LSym{Name: name}
+		s.SetABI(abi)
+		hash[name] = s
+		if init != nil {
+			init(s)
+		}
+	}
+	ctxt.hashmu.Unlock()
+	return s
+}
+
+// Lookup looks up the symbol with name name.
+// If it does not exist, it creates it.
+func (ctxt *Link) Lookup(name string) *LSym {
+	return ctxt.LookupInit(name, nil)
+}
+
+// LookupInit looks up the symbol with name name.
+// If it does not exist, it creates it and
+// passes it to init for one-time initialization.
+func (ctxt *Link) LookupInit(name string, init func(s *LSym)) *LSym {
+	ctxt.hashmu.Lock()
+	s := ctxt.hash[name]
+	if s == nil {
+		s = &LSym{Name: name}
+		ctxt.hash[name] = s
+		if init != nil {
+			init(s)
+		}
+	}
+	ctxt.hashmu.Unlock()
+	return s
+}
+
+func (ctxt *Link) Float32Sym(f float32) *LSym {
+	i := math.Float32bits(f)
+	name := fmt.Sprintf("$f32.%08x", i)
+	return ctxt.LookupInit(name, func(s *LSym) {
+		s.Size = 4
+		s.WriteFloat32(ctxt, 0, f)
+		s.Type = objabi.SRODATA
+		s.Set(AttrLocal, true)
+		s.Set(AttrContentAddressable, true)
+		ctxt.constSyms = append(ctxt.constSyms, s)
+	})
+}
+
+func (ctxt *Link) Float64Sym(f float64) *LSym {
+	i := math.Float64bits(f)
+	name := fmt.Sprintf("$f64.%016x", i)
+	return ctxt.LookupInit(name, func(s *LSym) {
+		s.Size = 8
+		s.WriteFloat64(ctxt, 0, f)
+		s.Type = objabi.SRODATA
+		s.Set(AttrLocal, true)
+		s.Set(AttrContentAddressable, true)
+		ctxt.constSyms = append(ctxt.constSyms, s)
+	})
+}
+
+func (ctxt *Link) Int64Sym(i int64) *LSym {
+	name := fmt.Sprintf("$i64.%016x", uint64(i))
+	return ctxt.LookupInit(name, func(s *LSym) {
+		s.Size = 8
+		s.WriteInt(ctxt, 0, 8, i)
+		s.Type = objabi.SRODATA
+		s.Set(AttrLocal, true)
+		s.Set(AttrContentAddressable, true)
+		ctxt.constSyms = append(ctxt.constSyms, s)
+	})
+}
+
+// Assign index to symbols.
+// asm is set to true if this is called by the assembler (i.e. not the compiler),
+// in which case all the symbols are non-package (for now).
+func (ctxt *Link) NumberSyms() {
+	if ctxt.Headtype == objabi.Haix {
+		// Data must be sorted to keep a constant order in TOC symbols.
+		// As they are created during Progedit, two symbols can be switched between
+		// two different compilations. Therefore, BuildID will be different.
+		// TODO: find a better place and optimize to only sort TOC symbols
+		sort.Slice(ctxt.Data, func(i, j int) bool {
+			return ctxt.Data[i].Name < ctxt.Data[j].Name
+		})
+	}
+
+	// Constant symbols are created late in the concurrent phase. Sort them
+	// to ensure a deterministic order.
+	sort.Slice(ctxt.constSyms, func(i, j int) bool {
+		return ctxt.constSyms[i].Name < ctxt.constSyms[j].Name
+	})
+	ctxt.Data = append(ctxt.Data, ctxt.constSyms...)
+	ctxt.constSyms = nil
+
+	ctxt.pkgIdx = make(map[string]int32)
+	ctxt.defs = []*LSym{}
+	ctxt.hashed64defs = []*LSym{}
+	ctxt.hasheddefs = []*LSym{}
+	ctxt.nonpkgdefs = []*LSym{}
+
+	var idx, hashedidx, hashed64idx, nonpkgidx int32
+	ctxt.traverseSyms(traverseDefs, func(s *LSym) {
+		// if Pkgpath is unknown, cannot hash symbols with relocations, as it
+		// may reference named symbols whose names are not fully expanded.
+		if s.ContentAddressable() && (ctxt.Pkgpath != "" || len(s.R) == 0) {
+			if s.Size <= 8 && len(s.R) == 0 && !strings.HasPrefix(s.Name, "type.") {
+				// We can use short hash only for symbols without relocations.
+				// Don't use short hash for type symbols, as they need special handling.
+				s.PkgIdx = goobj.PkgIdxHashed64
+				s.SymIdx = hashed64idx
+				if hashed64idx != int32(len(ctxt.hashed64defs)) {
+					panic("bad index")
+				}
+				ctxt.hashed64defs = append(ctxt.hashed64defs, s)
+				hashed64idx++
+			} else {
+				s.PkgIdx = goobj.PkgIdxHashed
+				s.SymIdx = hashedidx
+				if hashedidx != int32(len(ctxt.hasheddefs)) {
+					panic("bad index")
+				}
+				ctxt.hasheddefs = append(ctxt.hasheddefs, s)
+				hashedidx++
+			}
+		} else if isNonPkgSym(ctxt, s) {
+			s.PkgIdx = goobj.PkgIdxNone
+			s.SymIdx = nonpkgidx
+			if nonpkgidx != int32(len(ctxt.nonpkgdefs)) {
+				panic("bad index")
+			}
+			ctxt.nonpkgdefs = append(ctxt.nonpkgdefs, s)
+			nonpkgidx++
+		} else {
+			s.PkgIdx = goobj.PkgIdxSelf
+			s.SymIdx = idx
+			if idx != int32(len(ctxt.defs)) {
+				panic("bad index")
+			}
+			ctxt.defs = append(ctxt.defs, s)
+			idx++
+		}
+		s.Set(AttrIndexed, true)
+	})
+
+	ipkg := int32(1) // 0 is invalid index
+	nonpkgdef := nonpkgidx
+	ctxt.traverseSyms(traverseRefs|traverseAux, func(rs *LSym) {
+		if rs.PkgIdx != goobj.PkgIdxInvalid {
+			return
+		}
+		if !ctxt.Flag_linkshared {
+			// Assign special index for builtin symbols.
+			// Don't do it when linking against shared libraries, as the runtime
+			// may be in a different library.
+			if i := goobj.BuiltinIdx(rs.Name, int(rs.ABI())); i != -1 {
+				rs.PkgIdx = goobj.PkgIdxBuiltin
+				rs.SymIdx = int32(i)
+				rs.Set(AttrIndexed, true)
+				return
+			}
+		}
+		pkg := rs.Pkg
+		if rs.ContentAddressable() {
+			// for now, only support content-addressable symbols that are always locally defined.
+			panic("hashed refs unsupported for now")
+		}
+		if pkg == "" || pkg == "\"\"" || pkg == "_" || !rs.Indexed() {
+			rs.PkgIdx = goobj.PkgIdxNone
+			rs.SymIdx = nonpkgidx
+			rs.Set(AttrIndexed, true)
+			if nonpkgidx != nonpkgdef+int32(len(ctxt.nonpkgrefs)) {
+				panic("bad index")
+			}
+			ctxt.nonpkgrefs = append(ctxt.nonpkgrefs, rs)
+			nonpkgidx++
+			return
+		}
+		if k, ok := ctxt.pkgIdx[pkg]; ok {
+			rs.PkgIdx = k
+			return
+		}
+		rs.PkgIdx = ipkg
+		ctxt.pkgIdx[pkg] = ipkg
+		ipkg++
+	})
+}
+
+// Returns whether s is a non-package symbol, which needs to be referenced
+// by name instead of by index.
+func isNonPkgSym(ctxt *Link, s *LSym) bool {
+	if ctxt.IsAsm && !s.Static() {
+		// asm symbols are referenced by name only, except static symbols
+		// which are file-local and can be referenced by index.
+		return true
+	}
+	if ctxt.Flag_linkshared {
+		// The referenced symbol may be in a different shared library so
+		// the linker cannot see its index.
+		return true
+	}
+	if s.Pkg == "_" {
+		// The frontend uses package "_" to mark symbols that should not
+		// be referenced by index, e.g. linkname'd symbols.
+		return true
+	}
+	if s.DuplicateOK() {
+		// Dupok symbol needs to be dedup'd by name.
+		return true
+	}
+	return false
+}
+
+// StaticNamePref is the prefix the front end applies to static temporary
+// variables. When turned into LSyms, these can be tagged as static so
+// as to avoid inserting them into the linker's name lookup tables.
+const StaticNamePref = ".stmp_"
+
+type traverseFlag uint32
+
+const (
+	traverseDefs traverseFlag = 1 << iota
+	traverseRefs
+	traverseAux
+
+	traverseAll = traverseDefs | traverseRefs | traverseAux
+)
+
+// Traverse symbols based on flag, call fn for each symbol.
+func (ctxt *Link) traverseSyms(flag traverseFlag, fn func(*LSym)) {
+	lists := [][]*LSym{ctxt.Text, ctxt.Data, ctxt.ABIAliases}
+	for _, list := range lists {
+		for _, s := range list {
+			if flag&traverseDefs != 0 {
+				fn(s)
+			}
+			if flag&traverseRefs != 0 {
+				for _, r := range s.R {
+					if r.Sym != nil {
+						fn(r.Sym)
+					}
+				}
+			}
+			if flag&traverseAux != 0 {
+				if s.Gotype != nil {
+					fn(s.Gotype)
+				}
+				if s.Type == objabi.STEXT {
+					f := func(parent *LSym, aux *LSym) {
+						fn(aux)
+					}
+					ctxt.traverseFuncAux(flag, s, f)
+				}
+			}
+		}
+	}
+}
+
+func (ctxt *Link) traverseFuncAux(flag traverseFlag, fsym *LSym, fn func(parent *LSym, aux *LSym)) {
+	fninfo := fsym.Func()
+	pc := &fninfo.Pcln
+	if flag&traverseAux == 0 {
+		// NB: should it become necessary to walk aux sym reloc references
+		// without walking the aux syms themselves, this can be changed.
+		panic("should not be here")
+	}
+	for _, d := range pc.Funcdata {
+		if d != nil {
+			fn(fsym, d)
+		}
+	}
+	files := ctxt.PosTable.FileTable()
+	usedFiles := make([]goobj.CUFileIndex, 0, len(pc.UsedFiles))
+	for f := range pc.UsedFiles {
+		usedFiles = append(usedFiles, f)
+	}
+	sort.Slice(usedFiles, func(i, j int) bool { return usedFiles[i] < usedFiles[j] })
+	for _, f := range usedFiles {
+		if filesym := ctxt.Lookup(files[f]); filesym != nil {
+			fn(fsym, filesym)
+		}
+	}
+	for _, call := range pc.InlTree.nodes {
+		if call.Func != nil {
+			fn(fsym, call.Func)
+		}
+		f, _ := linkgetlineFromPos(ctxt, call.Pos)
+		if filesym := ctxt.Lookup(f); filesym != nil {
+			fn(fsym, filesym)
+		}
+	}
+
+	dwsyms := []*LSym{fninfo.dwarfRangesSym, fninfo.dwarfLocSym, fninfo.dwarfDebugLinesSym, fninfo.dwarfInfoSym}
+	for _, dws := range dwsyms {
+		if dws == nil || dws.Size == 0 {
+			continue
+		}
+		fn(fsym, dws)
+		if flag&traverseRefs != 0 {
+			for _, r := range dws.R {
+				if r.Sym != nil {
+					fn(dws, r.Sym)
+				}
+			}
+		}
+	}
+}
+
+// Traverse aux symbols, calling fn for each sym/aux pair.
+func (ctxt *Link) traverseAuxSyms(flag traverseFlag, fn func(parent *LSym, aux *LSym)) {
+	lists := [][]*LSym{ctxt.Text, ctxt.Data, ctxt.ABIAliases}
+	for _, list := range lists {
+		for _, s := range list {
+			if s.Gotype != nil {
+				if flag&traverseDefs != 0 {
+					fn(s, s.Gotype)
+				}
+			}
+			if s.Type != objabi.STEXT {
+				continue
+			}
+			ctxt.traverseFuncAux(flag, s, fn)
+		}
+	}
+}