podman

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// Derived from Inferno utils/6l/obj.c and utils/6l/span.c
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// https://bitbucket.org/inferno-os/inferno-os/src/master/utils/6l/obj.c
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// https://bitbucket.org/inferno-os/inferno-os/src/master/utils/6l/span.c
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//
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//	Copyright © 1994-1999 Lucent Technologies Inc.  All rights reserved.
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//	Portions Copyright © 1995-1997 C H Forsyth (forsyth@terzarima.net)
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//	Portions Copyright © 1997-1999 Vita Nuova Limited
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//	Portions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com)
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//	Portions Copyright © 2004,2006 Bruce Ellis
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//	Portions Copyright © 2005-2007 C H Forsyth (forsyth@terzarima.net)
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//	Revisions Copyright © 2000-2007 Lucent Technologies Inc. and others
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//	Portions Copyright © 2009 The Go Authors. All rights reserved.
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//
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// Permission is hereby granted, free of charge, to any person obtaining a copy
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// of this software and associated documentation files (the "Software"), to deal
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// in the Software without restriction, including without limitation the rights
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// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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// copies of the Software, and to permit persons to whom the Software is
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// furnished to do so, subject to the following conditions:
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//
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// The above copyright notice and this permission notice shall be included in
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// all copies or substantial portions of the Software.
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//
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// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
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// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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// THE SOFTWARE.
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package obj
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import (
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	"github.com/twitchyliquid64/golang-asm/objabi"
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	"log"
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	"math"
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)
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// Grow increases the length of s.P to lsiz.
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func (s *LSym) Grow(lsiz int64) {
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	siz := int(lsiz)
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	if int64(siz) != lsiz {
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		log.Fatalf("LSym.Grow size %d too long", lsiz)
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	}
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	if len(s.P) >= siz {
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		return
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	}
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	s.P = append(s.P, make([]byte, siz-len(s.P))...)
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}
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// GrowCap increases the capacity of s.P to c.
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func (s *LSym) GrowCap(c int64) {
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	if int64(cap(s.P)) >= c {
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		return
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	}
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	if s.P == nil {
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		s.P = make([]byte, 0, c)
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		return
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	}
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	b := make([]byte, len(s.P), c)
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	copy(b, s.P)
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	s.P = b
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}
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// prepwrite prepares to write data of size siz into s at offset off.
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func (s *LSym) prepwrite(ctxt *Link, off int64, siz int) {
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	if off < 0 || siz < 0 || off >= 1<<30 {
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		ctxt.Diag("prepwrite: bad off=%d siz=%d s=%v", off, siz, s)
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	}
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	switch s.Type {
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	case objabi.Sxxx, objabi.SBSS:
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		s.Type = objabi.SDATA
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	case objabi.SNOPTRBSS:
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		s.Type = objabi.SNOPTRDATA
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	case objabi.STLSBSS:
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		ctxt.Diag("cannot supply data for %v var %v", s.Type, s.Name)
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	}
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	l := off + int64(siz)
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	s.Grow(l)
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	if l > s.Size {
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		s.Size = l
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	}
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}
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// WriteFloat32 writes f into s at offset off.
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func (s *LSym) WriteFloat32(ctxt *Link, off int64, f float32) {
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	s.prepwrite(ctxt, off, 4)
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	ctxt.Arch.ByteOrder.PutUint32(s.P[off:], math.Float32bits(f))
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}
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// WriteFloat64 writes f into s at offset off.
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func (s *LSym) WriteFloat64(ctxt *Link, off int64, f float64) {
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	s.prepwrite(ctxt, off, 8)
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	ctxt.Arch.ByteOrder.PutUint64(s.P[off:], math.Float64bits(f))
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}
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// WriteInt writes an integer i of size siz into s at offset off.
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func (s *LSym) WriteInt(ctxt *Link, off int64, siz int, i int64) {
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	s.prepwrite(ctxt, off, siz)
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	switch siz {
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	default:
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		ctxt.Diag("WriteInt: bad integer size: %d", siz)
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	case 1:
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		s.P[off] = byte(i)
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	case 2:
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		ctxt.Arch.ByteOrder.PutUint16(s.P[off:], uint16(i))
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	case 4:
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		ctxt.Arch.ByteOrder.PutUint32(s.P[off:], uint32(i))
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	case 8:
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		ctxt.Arch.ByteOrder.PutUint64(s.P[off:], uint64(i))
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	}
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}
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func (s *LSym) writeAddr(ctxt *Link, off int64, siz int, rsym *LSym, roff int64, rtype objabi.RelocType) {
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	// Allow 4-byte addresses for DWARF.
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	if siz != ctxt.Arch.PtrSize && siz != 4 {
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		ctxt.Diag("WriteAddr: bad address size %d in %s", siz, s.Name)
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	}
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	s.prepwrite(ctxt, off, siz)
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	r := Addrel(s)
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	r.Off = int32(off)
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	if int64(r.Off) != off {
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		ctxt.Diag("WriteAddr: off overflow %d in %s", off, s.Name)
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	}
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	r.Siz = uint8(siz)
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	r.Sym = rsym
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	r.Type = rtype
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	r.Add = roff
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}
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// WriteAddr writes an address of size siz into s at offset off.
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// rsym and roff specify the relocation for the address.
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func (s *LSym) WriteAddr(ctxt *Link, off int64, siz int, rsym *LSym, roff int64) {
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	s.writeAddr(ctxt, off, siz, rsym, roff, objabi.R_ADDR)
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}
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// WriteCURelativeAddr writes a pointer-sized address into s at offset off.
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// rsym and roff specify the relocation for the address which will be
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// resolved by the linker to an offset from the DW_AT_low_pc attribute of
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// the DWARF Compile Unit of rsym.
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func (s *LSym) WriteCURelativeAddr(ctxt *Link, off int64, rsym *LSym, roff int64) {
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	s.writeAddr(ctxt, off, ctxt.Arch.PtrSize, rsym, roff, objabi.R_ADDRCUOFF)
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}
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// WriteOff writes a 4 byte offset to rsym+roff into s at offset off.
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// After linking the 4 bytes stored at s+off will be
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// rsym+roff-(start of section that s is in).
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func (s *LSym) WriteOff(ctxt *Link, off int64, rsym *LSym, roff int64) {
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	s.prepwrite(ctxt, off, 4)
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	r := Addrel(s)
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	r.Off = int32(off)
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	if int64(r.Off) != off {
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		ctxt.Diag("WriteOff: off overflow %d in %s", off, s.Name)
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	}
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	r.Siz = 4
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	r.Sym = rsym
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	r.Type = objabi.R_ADDROFF
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	r.Add = roff
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}
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// WriteWeakOff writes a weak 4 byte offset to rsym+roff into s at offset off.
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// After linking the 4 bytes stored at s+off will be
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// rsym+roff-(start of section that s is in).
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func (s *LSym) WriteWeakOff(ctxt *Link, off int64, rsym *LSym, roff int64) {
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	s.prepwrite(ctxt, off, 4)
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	r := Addrel(s)
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	r.Off = int32(off)
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	if int64(r.Off) != off {
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		ctxt.Diag("WriteOff: off overflow %d in %s", off, s.Name)
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	}
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	r.Siz = 4
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	r.Sym = rsym
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	r.Type = objabi.R_WEAKADDROFF
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	r.Add = roff
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}
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// WriteString writes a string of size siz into s at offset off.
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func (s *LSym) WriteString(ctxt *Link, off int64, siz int, str string) {
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	if siz < len(str) {
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		ctxt.Diag("WriteString: bad string size: %d < %d", siz, len(str))
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	}
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	s.prepwrite(ctxt, off, siz)
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	copy(s.P[off:off+int64(siz)], str)
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}
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// WriteBytes writes a slice of bytes into s at offset off.
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func (s *LSym) WriteBytes(ctxt *Link, off int64, b []byte) int64 {
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	s.prepwrite(ctxt, off, len(b))
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	copy(s.P[off:], b)
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	return off + int64(len(b))
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}
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func Addrel(s *LSym) *Reloc {
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	if s.R == nil {
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		s.R = make([]Reloc, 0, 4)
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	}
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	s.R = append(s.R, Reloc{})
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	return &s.R[len(s.R)-1]
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}
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