| // Derived from Inferno utils/6l/obj.c and utils/6l/span.c |
| // https://bitbucket.org/inferno-os/inferno-os/src/default/utils/6l/obj.c |
| // https://bitbucket.org/inferno-os/inferno-os/src/default/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/objabi" |
| "log" |
| "math" |
| ) |
| |
| // Grow increases the length of s.P to lsiz. |
| func (s *LSym) Grow(lsiz int64) { |
| siz := int(lsiz) |
| if int64(siz) != lsiz { |
| log.Fatalf("LSym.Grow size %d too long", lsiz) |
| } |
| if len(s.P) >= siz { |
| return |
| } |
| s.P = append(s.P, make([]byte, siz-len(s.P))...) |
| } |
| |
| // GrowCap increases the capacity of s.P to c. |
| func (s *LSym) GrowCap(c int64) { |
| if int64(cap(s.P)) >= c { |
| return |
| } |
| if s.P == nil { |
| s.P = make([]byte, 0, c) |
| return |
| } |
| b := make([]byte, len(s.P), c) |
| copy(b, s.P) |
| s.P = b |
| } |
| |
| // prepwrite prepares to write data of size siz into s at offset off. |
| func (s *LSym) prepwrite(ctxt *Link, off int64, siz int) { |
| if off < 0 || siz < 0 || off >= 1<<30 { |
| ctxt.Diag("prepwrite: bad off=%d siz=%d s=%v", off, siz, s) |
| } |
| switch s.Type { |
| case objabi.Sxxx, objabi.SBSS: |
| s.Type = objabi.SDATA |
| case objabi.SNOPTRBSS: |
| s.Type = objabi.SNOPTRDATA |
| case objabi.STLSBSS: |
| ctxt.Diag("cannot supply data for %v var %v", s.Type, s.Name) |
| } |
| l := off + int64(siz) |
| s.Grow(l) |
| if l > s.Size { |
| s.Size = l |
| } |
| } |
| |
| // WriteFloat32 writes f into s at offset off. |
| func (s *LSym) WriteFloat32(ctxt *Link, off int64, f float32) { |
| s.prepwrite(ctxt, off, 4) |
| ctxt.Arch.ByteOrder.PutUint32(s.P[off:], math.Float32bits(f)) |
| } |
| |
| // WriteFloat64 writes f into s at offset off. |
| func (s *LSym) WriteFloat64(ctxt *Link, off int64, f float64) { |
| s.prepwrite(ctxt, off, 8) |
| ctxt.Arch.ByteOrder.PutUint64(s.P[off:], math.Float64bits(f)) |
| } |
| |
| // WriteInt writes an integer i of size siz into s at offset off. |
| func (s *LSym) WriteInt(ctxt *Link, off int64, siz int, i int64) { |
| s.prepwrite(ctxt, off, siz) |
| switch siz { |
| default: |
| ctxt.Diag("WriteInt: bad integer size: %d", siz) |
| case 1: |
| s.P[off] = byte(i) |
| case 2: |
| ctxt.Arch.ByteOrder.PutUint16(s.P[off:], uint16(i)) |
| case 4: |
| ctxt.Arch.ByteOrder.PutUint32(s.P[off:], uint32(i)) |
| case 8: |
| ctxt.Arch.ByteOrder.PutUint64(s.P[off:], uint64(i)) |
| } |
| } |
| |
| func (s *LSym) writeAddr(ctxt *Link, off int64, siz int, rsym *LSym, roff int64, rtype objabi.RelocType) { |
| // Allow 4-byte addresses for DWARF. |
| if siz != ctxt.Arch.PtrSize && siz != 4 { |
| ctxt.Diag("WriteAddr: bad address size %d in %s", siz, s.Name) |
| } |
| s.prepwrite(ctxt, off, siz) |
| r := Addrel(s) |
| r.Off = int32(off) |
| if int64(r.Off) != off { |
| ctxt.Diag("WriteAddr: off overflow %d in %s", off, s.Name) |
| } |
| r.Siz = uint8(siz) |
| r.Sym = rsym |
| r.Type = rtype |
| r.Add = roff |
| } |
| |
| // WriteAddr writes an address of size siz into s at offset off. |
| // rsym and roff specify the relocation for the address. |
| func (s *LSym) WriteAddr(ctxt *Link, off int64, siz int, rsym *LSym, roff int64) { |
| s.writeAddr(ctxt, off, siz, rsym, roff, objabi.R_ADDR) |
| } |
| |
| // WriteCURelativeAddr writes a pointer-sized address into s at offset off. |
| // rsym and roff specify the relocation for the address which will be |
| // resolved by the linker to an offset from the DW_AT_low_pc attribute of |
| // the DWARF Compile Unit of rsym. |
| func (s *LSym) WriteCURelativeAddr(ctxt *Link, off int64, rsym *LSym, roff int64) { |
| s.writeAddr(ctxt, off, ctxt.Arch.PtrSize, rsym, roff, objabi.R_ADDRCUOFF) |
| } |
| |
| // WriteOff writes a 4 byte offset to rsym+roff into s at offset off. |
| // After linking the 4 bytes stored at s+off will be |
| // rsym+roff-(start of section that s is in). |
| func (s *LSym) WriteOff(ctxt *Link, off int64, rsym *LSym, roff int64) { |
| s.prepwrite(ctxt, off, 4) |
| r := Addrel(s) |
| r.Off = int32(off) |
| if int64(r.Off) != off { |
| ctxt.Diag("WriteOff: off overflow %d in %s", off, s.Name) |
| } |
| r.Siz = 4 |
| r.Sym = rsym |
| r.Type = objabi.R_ADDROFF |
| r.Add = roff |
| } |
| |
| // WriteWeakOff writes a weak 4 byte offset to rsym+roff into s at offset off. |
| // After linking the 4 bytes stored at s+off will be |
| // rsym+roff-(start of section that s is in). |
| func (s *LSym) WriteWeakOff(ctxt *Link, off int64, rsym *LSym, roff int64) { |
| s.prepwrite(ctxt, off, 4) |
| r := Addrel(s) |
| r.Off = int32(off) |
| if int64(r.Off) != off { |
| ctxt.Diag("WriteOff: off overflow %d in %s", off, s.Name) |
| } |
| r.Siz = 4 |
| r.Sym = rsym |
| r.Type = objabi.R_WEAKADDROFF |
| r.Add = roff |
| } |
| |
| // WriteString writes a string of size siz into s at offset off. |
| func (s *LSym) WriteString(ctxt *Link, off int64, siz int, str string) { |
| if siz < len(str) { |
| ctxt.Diag("WriteString: bad string size: %d < %d", siz, len(str)) |
| } |
| s.prepwrite(ctxt, off, siz) |
| copy(s.P[off:off+int64(siz)], str) |
| } |
| |
| // WriteBytes writes a slice of bytes into s at offset off. |
| func (s *LSym) WriteBytes(ctxt *Link, off int64, b []byte) int64 { |
| s.prepwrite(ctxt, off, len(b)) |
| copy(s.P[off:], b) |
| return off + int64(len(b)) |
| } |
| |
| func Addrel(s *LSym) *Reloc { |
| if s.R == nil { |
| s.R = make([]Reloc, 0, 4) |
| } |
| s.R = append(s.R, Reloc{}) |
| return &s.R[len(s.R)-1] |
| } |
