diff options
Diffstat (limited to 'src/cmd/internal/obj/data.go')
| -rw-r--r-- | src/cmd/internal/obj/data.go | 200 |
1 files changed, 200 insertions, 0 deletions
diff --git a/src/cmd/internal/obj/data.go b/src/cmd/internal/obj/data.go new file mode 100644 index 0000000..f32e07a --- /dev/null +++ b/src/cmd/internal/obj/data.go @@ -0,0 +1,200 @@ +// 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/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] +} |