go/src/cmd/internal/obj/data.go

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// Derived from Inferno utils/6l/obj.c and utils/6l/span.c
// http://code.google.com/p/inferno-os/source/browse/utils/6l/obj.c
// http://code.google.com/p/inferno-os/source/browse/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 (
"log"
"math"
)
func Symgrow(ctxt *Link, s *LSym, lsiz int64) {
siz := int(lsiz)
if int64(siz) != lsiz {
log.Fatalf("Symgrow size %d too long", lsiz)
}
if len(s.P) >= siz {
return
}
// TODO(dfc) append cap-len at once, rather than
// one byte at a time.
for cap(s.P) < siz {
s.P = append(s.P[:cap(s.P)], 0)
}
s.P = s.P[:siz]
}
cmd/compile: write some static data directly Instead of generating ADATA instructions for static data, write that static data directly into the linker sym. This is considerably more efficient. The assembler still generates ADATA instructions, so the ADATA machinery cannot be dismantled yet. (Future work.) Skipping ADATA has a significant impact compiling the unicode package, which has lots of static data. name old time/op new time/op delta Unicode 227ms ±10% 192ms ± 4% -15.61% (p=0.000 n=29+30) name old alloc/op new alloc/op delta Unicode 51.0MB ± 0% 45.8MB ± 0% -10.29% (p=0.000 n=30+30) name old allocs/op new allocs/op delta Unicode 610k ± 0% 578k ± 0% -5.29% (p=0.000 n=30+30) This does not pass toolstash -cmp, because this changes the order in which some relocations get added, and thus it changes the output from the compiler. It is not worth the execution time to sort the relocs in the normal case. However, compiling with -S -v generates identical output if (1) you suppress printing of ADATA progs in flushplist and (2) you suppress printing of cpu timing. It is reasonable to suppress printing the ADATA progs, since the data itself is dumped later. I am therefore fairly confident that all changes are superficial and non-functional. Fixes #14786, although there's more to do in general. Change-Id: I8dfabe7b423b31a30e516cfdf005b62a2e9ccd82 Reviewed-on: https://go-review.googlesource.com/20645 Reviewed-by: Matthew Dempsky <mdempsky@google.com> Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-03-13 12:16:43 -07:00
// prepwrite prepares to write data of size siz into s at offset off.
func (s *LSym) prepwrite(ctxt *Link, off, siz int64) {
if off < 0 || siz < 0 || off >= 1<<30 {
cmd/compile: write some static data directly Instead of generating ADATA instructions for static data, write that static data directly into the linker sym. This is considerably more efficient. The assembler still generates ADATA instructions, so the ADATA machinery cannot be dismantled yet. (Future work.) Skipping ADATA has a significant impact compiling the unicode package, which has lots of static data. name old time/op new time/op delta Unicode 227ms ±10% 192ms ± 4% -15.61% (p=0.000 n=29+30) name old alloc/op new alloc/op delta Unicode 51.0MB ± 0% 45.8MB ± 0% -10.29% (p=0.000 n=30+30) name old allocs/op new allocs/op delta Unicode 610k ± 0% 578k ± 0% -5.29% (p=0.000 n=30+30) This does not pass toolstash -cmp, because this changes the order in which some relocations get added, and thus it changes the output from the compiler. It is not worth the execution time to sort the relocs in the normal case. However, compiling with -S -v generates identical output if (1) you suppress printing of ADATA progs in flushplist and (2) you suppress printing of cpu timing. It is reasonable to suppress printing the ADATA progs, since the data itself is dumped later. I am therefore fairly confident that all changes are superficial and non-functional. Fixes #14786, although there's more to do in general. Change-Id: I8dfabe7b423b31a30e516cfdf005b62a2e9ccd82 Reviewed-on: https://go-review.googlesource.com/20645 Reviewed-by: Matthew Dempsky <mdempsky@google.com> Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-03-13 12:16:43 -07:00
log.Fatalf("prepwrite: bad off=%d siz=%d", off, siz)
}
if s.Type == SBSS || s.Type == STLSBSS {
ctxt.Diag("cannot supply data for BSS var")
}
Symgrow(ctxt, s, off+siz)
}
// 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, siz int64, i int64) {
s.prepwrite(ctxt, off, siz)
switch siz {
default:
ctxt.Diag("WriteInt: bad integer size: %d", siz)
cmd/compile: write some static data directly Instead of generating ADATA instructions for static data, write that static data directly into the linker sym. This is considerably more efficient. The assembler still generates ADATA instructions, so the ADATA machinery cannot be dismantled yet. (Future work.) Skipping ADATA has a significant impact compiling the unicode package, which has lots of static data. name old time/op new time/op delta Unicode 227ms ±10% 192ms ± 4% -15.61% (p=0.000 n=29+30) name old alloc/op new alloc/op delta Unicode 51.0MB ± 0% 45.8MB ± 0% -10.29% (p=0.000 n=30+30) name old allocs/op new allocs/op delta Unicode 610k ± 0% 578k ± 0% -5.29% (p=0.000 n=30+30) This does not pass toolstash -cmp, because this changes the order in which some relocations get added, and thus it changes the output from the compiler. It is not worth the execution time to sort the relocs in the normal case. However, compiling with -S -v generates identical output if (1) you suppress printing of ADATA progs in flushplist and (2) you suppress printing of cpu timing. It is reasonable to suppress printing the ADATA progs, since the data itself is dumped later. I am therefore fairly confident that all changes are superficial and non-functional. Fixes #14786, although there's more to do in general. Change-Id: I8dfabe7b423b31a30e516cfdf005b62a2e9ccd82 Reviewed-on: https://go-review.googlesource.com/20645 Reviewed-by: Matthew Dempsky <mdempsky@google.com> Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-03-13 12:16:43 -07:00
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))
}
}
// 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, siz int64, rsym *LSym, roff int64) {
if siz != int64(ctxt.Arch.Ptrsize) {
ctxt.Diag("WriteAddr: bad address size: %d", siz)
}
cmd/compile: write some static data directly Instead of generating ADATA instructions for static data, write that static data directly into the linker sym. This is considerably more efficient. The assembler still generates ADATA instructions, so the ADATA machinery cannot be dismantled yet. (Future work.) Skipping ADATA has a significant impact compiling the unicode package, which has lots of static data. name old time/op new time/op delta Unicode 227ms ±10% 192ms ± 4% -15.61% (p=0.000 n=29+30) name old alloc/op new alloc/op delta Unicode 51.0MB ± 0% 45.8MB ± 0% -10.29% (p=0.000 n=30+30) name old allocs/op new allocs/op delta Unicode 610k ± 0% 578k ± 0% -5.29% (p=0.000 n=30+30) This does not pass toolstash -cmp, because this changes the order in which some relocations get added, and thus it changes the output from the compiler. It is not worth the execution time to sort the relocs in the normal case. However, compiling with -S -v generates identical output if (1) you suppress printing of ADATA progs in flushplist and (2) you suppress printing of cpu timing. It is reasonable to suppress printing the ADATA progs, since the data itself is dumped later. I am therefore fairly confident that all changes are superficial and non-functional. Fixes #14786, although there's more to do in general. Change-Id: I8dfabe7b423b31a30e516cfdf005b62a2e9ccd82 Reviewed-on: https://go-review.googlesource.com/20645 Reviewed-by: Matthew Dempsky <mdempsky@google.com> Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-03-13 12:16:43 -07:00
s.prepwrite(ctxt, off, siz)
r := Addrel(s)
r.Off = int32(off)
r.Siz = uint8(siz)
r.Sym = rsym
r.Type = R_ADDR
r.Add = roff
}
// WriteString writes a string of size siz into s at offset off.
func (s *LSym) WriteString(ctxt *Link, off, siz int64, str string) {
if siz < int64(len(str)) {
ctxt.Diag("WriteString: bad string size: %d < %d", siz, len(str))
}
cmd/compile: write some static data directly Instead of generating ADATA instructions for static data, write that static data directly into the linker sym. This is considerably more efficient. The assembler still generates ADATA instructions, so the ADATA machinery cannot be dismantled yet. (Future work.) Skipping ADATA has a significant impact compiling the unicode package, which has lots of static data. name old time/op new time/op delta Unicode 227ms ±10% 192ms ± 4% -15.61% (p=0.000 n=29+30) name old alloc/op new alloc/op delta Unicode 51.0MB ± 0% 45.8MB ± 0% -10.29% (p=0.000 n=30+30) name old allocs/op new allocs/op delta Unicode 610k ± 0% 578k ± 0% -5.29% (p=0.000 n=30+30) This does not pass toolstash -cmp, because this changes the order in which some relocations get added, and thus it changes the output from the compiler. It is not worth the execution time to sort the relocs in the normal case. However, compiling with -S -v generates identical output if (1) you suppress printing of ADATA progs in flushplist and (2) you suppress printing of cpu timing. It is reasonable to suppress printing the ADATA progs, since the data itself is dumped later. I am therefore fairly confident that all changes are superficial and non-functional. Fixes #14786, although there's more to do in general. Change-Id: I8dfabe7b423b31a30e516cfdf005b62a2e9ccd82 Reviewed-on: https://go-review.googlesource.com/20645 Reviewed-by: Matthew Dempsky <mdempsky@google.com> Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-03-13 12:16:43 -07:00
s.prepwrite(ctxt, off, siz)
copy(s.P[off:off+siz], str)
}
func Addrel(s *LSym) *Reloc {
s.R = append(s.R, Reloc{})
return &s.R[len(s.R)-1]
}
func Setuintxx(ctxt *Link, s *LSym, off int64, v uint64, wid int64) int64 {
if s.Type == 0 {
s.Type = SDATA
}
if s.Size < off+wid {
s.Size = off + wid
Symgrow(ctxt, s, s.Size)
}
switch wid {
case 1:
s.P[off] = uint8(v)
case 2:
ctxt.Arch.ByteOrder.PutUint16(s.P[off:], uint16(v))
case 4:
ctxt.Arch.ByteOrder.PutUint32(s.P[off:], uint32(v))
case 8:
ctxt.Arch.ByteOrder.PutUint64(s.P[off:], uint64(v))
}
return off + wid
}