github.com/gagliardetto/golang-go@v0.0.0-20201020153340-53909ea70814/cmd/internal/obj/ld.go (about)

     1  // Derived from Inferno utils/6l/obj.c and utils/6l/span.c
     2  // https://bitbucket.org/inferno-os/inferno-os/src/default/utils/6l/obj.c
     3  // https://bitbucket.org/inferno-os/inferno-os/src/default/utils/6l/span.c
     4  //
     5  //	Copyright © 1994-1999 Lucent Technologies Inc.  All rights reserved.
     6  //	Portions Copyright © 1995-1997 C H Forsyth (forsyth@terzarima.net)
     7  //	Portions Copyright © 1997-1999 Vita Nuova Limited
     8  //	Portions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com)
     9  //	Portions Copyright © 2004,2006 Bruce Ellis
    10  //	Portions Copyright © 2005-2007 C H Forsyth (forsyth@terzarima.net)
    11  //	Revisions Copyright © 2000-2007 Lucent Technologies Inc. and others
    12  //	Portions Copyright © 2009 The Go Authors. All rights reserved.
    13  //
    14  // Permission is hereby granted, free of charge, to any person obtaining a copy
    15  // of this software and associated documentation files (the "Software"), to deal
    16  // in the Software without restriction, including without limitation the rights
    17  // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
    18  // copies of the Software, and to permit persons to whom the Software is
    19  // furnished to do so, subject to the following conditions:
    20  //
    21  // The above copyright notice and this permission notice shall be included in
    22  // all copies or substantial portions of the Software.
    23  //
    24  // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
    25  // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
    26  // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
    27  // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
    28  // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
    29  // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
    30  // THE SOFTWARE.
    31  
    32  package obj
    33  
    34  /*
    35   * add library to library list.
    36   *	srcref: src file referring to package
    37   *	objref: object file referring to package
    38   *	file: object file, e.g., /home/rsc/go/pkg/container/vector.a
    39   *	pkg: package import path, e.g. container/vector
    40   */
    41  
    42  const (
    43  	LOG = 5
    44  )
    45  
    46  func mkfwd(sym *LSym) {
    47  	var dwn [LOG]int32
    48  	var cnt [LOG]int32
    49  	var lst [LOG]*Prog
    50  
    51  	for i := 0; i < LOG; i++ {
    52  		if i == 0 {
    53  			cnt[i] = 1
    54  		} else {
    55  			cnt[i] = LOG * cnt[i-1]
    56  		}
    57  		dwn[i] = 1
    58  		lst[i] = nil
    59  	}
    60  
    61  	i := 0
    62  	for p := sym.Func.Text; p != nil && p.Link != nil; p = p.Link {
    63  		i--
    64  		if i < 0 {
    65  			i = LOG - 1
    66  		}
    67  		p.Forwd = nil
    68  		dwn[i]--
    69  		if dwn[i] <= 0 {
    70  			dwn[i] = cnt[i]
    71  			if lst[i] != nil {
    72  				lst[i].Forwd = p
    73  			}
    74  			lst[i] = p
    75  		}
    76  	}
    77  }
    78  
    79  func Appendp(q *Prog, newprog ProgAlloc) *Prog {
    80  	p := newprog()
    81  	p.Link = q.Link
    82  	q.Link = p
    83  	p.Pos = q.Pos
    84  	return p
    85  }