Commit Graph

110 Commits

Author SHA1 Message Date
LE Manh Cuong 12dbd20a50 cmd/link: set .dynsym info field
.dynsym section info field is the index of first non-local symbol, mean
the number of local symbols.

The go linker have never ever set it before, so just set it.

Fixes #33358

Change-Id: Ifde2deb7c15471b04d565861f5d81daffb0c0d3d
Reviewed-on: https://go-review.googlesource.com/c/go/+/187979
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2019-08-31 15:49:08 +00:00
Russ Cox d6b06f0254 cmd/link: make it easy to find binary versions
It is useful to be able to dig the Go version out of a binary,
even a stripped binary. rsc.io/goversion does this for x86
binaries by disassembling the binary to find runtime/proc.go's
startup-time reference to runtime.buildVersion's address.
That approach is quite fragile: the implementation doesn't
work for non-x86 and must be updated as the generated
code changes.

rsc.io/goversion finds the module version string by looking
for random 16-byte framing around the actual string.
This is less fragile but fairly kludgy and requires scanning
the entire data segment.

cmd/buildid finds the build ID by looking for an ELF note
or else falling back to scanning the beginning of the text
segment for a magic string. This has proved quite reliable
and doesn't require scanning much of the binary.

This CL makes it possible to find the Go and module versions
using a scan more like the build ID scan: a symbol early in
the writable data segment starts with a magic number and
then has pointers to the two string variables.

Setting up for "go version <binary>".

For #31624.

Change-Id: I78ea8c52fe1686b5cc5a829ca5f198104d10ebf0
Reviewed-on: https://go-review.googlesource.com/c/go/+/173342
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Jay Conrod <jayconrod@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2019-04-26 13:51:52 +00:00
Daniel Martí 49662bc6b0 all: simplify multiple for loops
If a for loop has a simple condition and begins with a simple
"if x { break; }"; we can simply add "!x" to the loop's condition.

While at it, simplify a few assignments to use the common pattern
"x := staticDefault; if cond { x = otherValue(); }".

Finally, simplify a couple of var declarations.

Change-Id: I413982c6abd32905adc85a9a666cb3819139c19f
Reviewed-on: https://go-review.googlesource.com/c/go/+/165342
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2019-03-08 14:29:19 +00:00
Tobias Klauser e27402aee0 cmd/dist, cmd/link: allow passing default dynamic linker/loader
Add an environment variable to make.bash to allow setting the default
dynamic linker/loader. This fixes alpine builds to use
/lib/ld-musl-x86_64.so.1:

  $ readelf -l ../bin/go | grep 'interpreter:' | sed -e 's/^.*interpreter: \(.*\)[]]/\1/'
  /lib/ld-musl-x86_64.so.1

Also re-enable the internal linker tests that were previously disabled
for alpine (CL 41759, CL 41678).

Fixes #18243
Updates #19938

This resurrects CL 50070 authored by Jessie Frazelle.

Change-Id: I132b5282045a3d60c8568e3b002a7f075eac2d93
Reviewed-on: https://go-review.googlesource.com/c/163977
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2019-03-01 06:06:13 +00:00
Igor Zhilianin f90e89e675 all: fix a bunch of misspellings
Change-Id: If2954bdfc551515403706b2cd0dde94e45936e08
GitHub-Last-Rev: d4cfc41a55
GitHub-Pull-Request: golang/go#28049
Reviewed-on: https://go-review.googlesource.com/c/140299
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-10-06 15:40:03 +00:00
Than McIntosh 09df9b06a1 cmd/link: split out Extname into cold portion of sym.Symbol
Create a new "AuxSymbol" struct into which 'cold' or 'infrequently
set' symbol fields are located. Move the Extname field from the
main Symbol struct to AuxSymbol.

Updates #26186

Change-Id: I9e795fb0cc48f978e2818475fa073ed9f2db202d
Reviewed-on: https://go-review.googlesource.com/125476
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-08-30 12:33:58 +00:00
Than McIntosh f00bfb385b cmd/link: split off 'Dynimp' string fields to reduce sym.Symbol size
The linker's sym.Symbol struct contains two string fields, "Dynimplib"
and "Dynimpvers" that are used only in very specific circumstances
(for many symbols, such as DWARF syms, they are wasted space). Split
these two off into a separate struct, then point to an instance of
that struct when needed. This reduces the size of sym.Symbol so as to
save space in the common case.

Updates #26186

Change-Id: Id9c74824e78423a215c8cbc105b72665525a1eff
Reviewed-on: https://go-review.googlesource.com/121916
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2018-07-03 14:48:40 +00:00
Heschi Kreinick 594eae5ad0 cmd/link: compress DWARF sections in ELF binaries
Forked from CL 111895.

The trickiest part of this is that the binary layout code (blk,
elfshbits, and various other things) assumes a constant offset between
symbols' and sections' file locations and their virtual addresses.
Compression, of course, breaks this constant offset. But we need to
assign virtual addresses to everything before compression in order to
resolve relocations before compression. As a result, compression needs
to re-compute the "address" of the DWARF sections and symbols based on
their compressed size. Luckily, these are at the end of the file, so
this doesn't perturb any other sections or symbols. (And there is, of
course, a surprising amount of code that assumes the DWARF segment
comes last, so what's one more place?)

Relevant benchmarks:
name        old time/op     new time/op     delta
StdCmd          10.3s ± 2%      10.8s ± 1%   +5.43%  (p=0.000 n=30+30)

name        old text-bytes  new text-bytes  delta
HelloSize       746kB ± 0%      746kB ± 0%     ~     (all equal)
CmdGoSize      8.41MB ± 0%     8.41MB ± 0%     ~     (all equal)
[Geo mean]     2.50MB          2.50MB        +0.00%

name        old data-bytes  new data-bytes  delta
HelloSize      10.6kB ± 0%     10.6kB ± 0%     ~     (all equal)
CmdGoSize       252kB ± 0%      252kB ± 0%     ~     (all equal)
[Geo mean]     51.5kB          51.5kB        +0.00%

name        old bss-bytes   new bss-bytes   delta
HelloSize       125kB ± 0%      125kB ± 0%     ~     (all equal)
CmdGoSize       145kB ± 0%      145kB ± 0%     ~     (all equal)
[Geo mean]      135kB           135kB        +0.00%

name        old exe-bytes   new exe-bytes   delta
HelloSize      1.60MB ± 0%     1.05MB ± 0%  -34.39%  (p=0.000 n=30+30)
CmdGoSize      16.5MB ± 0%     11.3MB ± 0%  -31.76%  (p=0.000 n=30+30)
[Geo mean]     5.14MB          3.44MB       -33.08%

Fixes #11799.
Updates #6853.

Change-Id: I64197afe4c01a237523a943088051ee056331c6f
Reviewed-on: https://go-review.googlesource.com/118276
Run-TryBot: Heschi Kreinick <heschi@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2018-06-15 20:01:53 +00:00
Daniel Martí a6b183fabd cmd/link/internal/ld: simple cleanups
Simplify some C-style loops with range statements, and move some
declarations closer to their uses.

While at it, ensure that all the SymbolType consts are typed.

Change-Id: I04b06afb2c1fb249ef8093a0c5cca0a597d1e05c
Reviewed-on: https://go-review.googlesource.com/105217
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2018-04-27 01:45:19 +00:00
Daniel Martí 14393c5cd4 cmd: remove a few more unused parameters
ssa's pos parameter on the Const* funcs is unused, so remove it.

ld's alloc parameter on elfnote is always true, so remove the arguments
and simplify the code.

Finally, arm's addpltreloc never has its return parameter used, so
remove it.

Change-Id: I63387ecf6ab7b5f7c20df36be823322bb98427b8
Reviewed-on: https://go-review.googlesource.com/104456
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2018-04-09 17:10:25 +00:00
quasilyte da02dcda02 cmd/link/internal/ld: make Thearch unexported
s/Thearch/thearch/

This reduces the amount of exported global variables,
which in turn could make it easier to refactor them later.

Also updated somewhat vague comment about ld.Thearch.
There is no need for Thearch to be exported as Archinit is
called by ld.Main.

Updates #22095

Change-Id: I266b291f6eac0165f70c51964738206e066cea08
Reviewed-on: https://go-review.googlesource.com/103878
Run-TryBot: Iskander Sharipov <iskander.sharipov@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-04-02 23:39:16 +00:00
Michael Hudson-Doyle 1b8987f1a7 cmd/link: replace SSUB with an attribute bit
There is some stuff I don't understand very well involved in SSUB, better words
for the documentation gratefully accepted.

As this is the last use of a bit in SMASK, kill that off too.

Change-Id: Iddff1c9b2af02c9dfb12ac8e668d004e4642f997
Reviewed-on: https://go-review.googlesource.com/42026
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-10-24 23:06:28 +00:00
David Crawshaw 38cfeb9cb5 cmd/link: move Headtype global to ctxt
For #22095

Change-Id: Idcfdfe8a94db8626392658bb93429454238f648a
Reviewed-on: https://go-review.googlesource.com/70835
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-21 00:51:14 +00:00
David Crawshaw d05f82a11a cmd/link: move Iself global to ctxt
For #22095

Change-Id: Iba3dffc782cecc15ea0e90a971a2734729984945
Reviewed-on: https://go-review.googlesource.com/70834
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-20 23:41:16 +00:00
David Crawshaw 6738c494ad cmd/link: move FlagLinkshared global to ctxt
For #22095

Change-Id: Ica6b3391541fe5a0355620d7c4a5107cf53eee82
Reviewed-on: https://go-review.googlesource.com/70833
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-20 23:40:56 +00:00
David Crawshaw ecfa7375e4 cmd/link: move ELF reader to its own package
Along the way, switch to using relocation constants from debug/elf.

For #22095

Change-Id: I1a64353619f95dde5aa39060c4b9d001af7dc1e4
Reviewed-on: https://go-review.googlesource.com/69013
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-11 20:53:39 +00:00
Daniel Martí 966c459fa4 cmd/link: various cleanups using tools
* remove unnecessary explicit types
* remove dead assignments
* remove unused fields
* unindent code using early continues
* remove some unnecessary type conversions
* remove some unused func parameters

Change-Id: I202c67e92940beacbd80fc2dc179f9556dc5d9e5
Reviewed-on: https://go-review.googlesource.com/69118
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2017-10-09 22:08:17 +00:00
David Crawshaw 2e8545531e cmd/link: move build/link mode globals into ctxt
Replace Buildmode with BuildMode and Linkmode with LinkMode.

For #22095

Change-Id: I51a6f5719d107727bca29ec8e68e3e9d87e31e33
Reviewed-on: https://go-review.googlesource.com/68334
Run-TryBot: David Crawshaw <crawshaw@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-10-06 13:49:11 +00:00
David Crawshaw a910fe2c83 cmd/link: move Library type to sym package
For #22095

Change-Id: I2cb0d3e0aaf9f97952cf8dda0e99a4379e275020
Reviewed-on: https://go-review.googlesource.com/68332
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Dave Cheney <dave@cheney.net>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-05 12:21:19 +00:00
David Crawshaw 475d92ba4d cmd/link: put symbol data types in new package
For #22095

Change-Id: I07c288208d94dabae164c2ca0a067402a8e5c2e6
Reviewed-on: https://go-review.googlesource.com/68331
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-05 10:50:18 +00:00
David Crawshaw 0346664421 cmd/link: convert symbol Add* functions to methods
Also reduce the passed context from *Link to *sys.Arch, so fewer
data dependencies need to be wired through all the code dealing
with symbols.

For #22095

Change-Id: I50969405d6562c5152bd1a3c443b72413e9b70bc
Reviewed-on: https://go-review.googlesource.com/67313
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-04 12:22:30 +00:00
David Crawshaw 5fe9bbcf63 cmd/link: remove coutbuf global variable
Begin passing coutbuf by as a parameter. To make the initial plumbing
pass easier, it is also a field in the standard ctxt parameter.

Consolidate the byte writing functions into the OutBuf object.
The result is less architecture-dependent initialization.

To avoid plumbing out everywhere we want to report an error, move
handling of out file deletion to an AtExit function.

For #22095

Change-Id: I0863695241562e0662ae3669666c7922b8c846f9
Reviewed-on: https://go-review.googlesource.com/67318
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-04 00:37:27 +00:00
David Crawshaw 5d95de2072 cmd/link: remove SysArch global variable
For #22095

Change-Id: I9d1f0d93f8fd701a24af826dc903eea2bc235de2
Reviewed-on: https://go-review.googlesource.com/67317
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-03 23:32:02 +00:00
Dave Cheney ed815d0038 cmd/link/internal/ld: reduce the scope of some local declarations
Move some local declarations closer to their use, reducing their
respective lifetimes. Spotted while reviewing CL 67318.

Change-Id: I68db67fe8530344d95e50efb6587bc724e1171f5
Reviewed-on: https://go-review.googlesource.com/67370
Run-TryBot: Dave Cheney <dave@cheney.net>
Reviewed-by: Marvin Stenger <marvin.stenger94@gmail.com>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-10-01 22:00:18 +00:00
Matthew Dempsky f84a1db19f cmd/link: replace unrolled Cput loops with Cwrite/Cwritestring
Passes toolstash-check -all.

Change-Id: I1c85a2c0390517f4e9cdbddddbf3c353edca65b3
Reviewed-on: https://go-review.googlesource.com/64051
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-09-15 19:09:39 +00:00
Hiroshi Ioka bce795fb1f cmd/link: unexport Elfadddynsym
Change-Id: Ifc66bd8c32e788f35da3bd105bcdcfd04bd3dabc
Reviewed-on: https://go-review.googlesource.com/59414
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
2017-08-29 23:29:00 +00:00
Hiroshi Ioka 0c4d035ca8 cmd/link: refactor *reloc
* use bool instead of int if it's adequate.
* remove blank lines.

Change-Id: Ic4a5644a33ed9fc7ce388ef8ba15f1732446fcfc
Reviewed-on: https://go-review.googlesource.com/59375
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-08-28 05:42:48 +00:00
Ian Lance Taylor cd5c10f040 cmd/link: set correct alignment of ELF note section
Otherwise the default computation in symalign kicked in, setting the
alignment to be too high. This didn't matter with GNU ld, which put
each loadable note into a separate PT_NOTE segment, but it did matter
with gold which accumulated them all into a single PT_NOTE segment,
respecting the requested alignment. In the single PT_NOTE segment
generated by gold, the incorrect section alignment made the notes
unreadable.

Fixes #21564

Change-Id: I15eb408bb04a2566c9fdfb6828e14188d9ef2280
Reviewed-on: https://go-review.googlesource.com/58290
Reviewed-by: Russ Cox <rsc@golang.org>
2017-08-24 16:54:18 +00:00
Hiroshi Ioka 2763672ecb cmd/link: show native relocation type name in error messages
Change-Id: I7f7b1e7ef832d53a93562b08ae914d023247c2c0
Reviewed-on: https://go-review.googlesource.com/56312
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-08-17 23:41:25 +00:00
Hiroshi Ioka 1ee701e857 cmd/link: improve error message
ld.SymKind and objabi.RelocType have string representations,
which is human friendly. Prefer to use it.

Change-Id: I458ee0ca5866be0db8462c36cd053561a8206c95
Reviewed-on: https://go-review.googlesource.com/55253
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-08-15 00:28:27 +00:00
Heschi Kreinick 4c54a047c6 [dev.debug] cmd/compile: better DWARF with optimizations on
Debuggers use DWARF information to find local variables on the
stack and in registers. Prior to this CL, the DWARF information for
functions claimed that all variables were on the stack at all times.
That's incorrect when optimizations are enabled, and results in
debuggers showing data that is out of date or complete gibberish.

After this CL, the compiler is capable of representing variable
locations more accurately, and attempts to do so. Due to limitations of
the SSA backend, it's not possible to be completely correct.

There are a number of problems in the current design. One of the easier
to understand is that variable names currently must be attached to an
SSA value, but not all assignments in the source code actually result
in machine code. For example:

  type myint int
  var a int
  b := myint(int)
and
  b := (*uint64)(unsafe.Pointer(a))

don't generate machine code because the underlying representation is the
same, so the correct value of b will not be set when the user would
expect.

Generating the more precise debug information is behind a flag,
dwarflocationlists. Because of the issues described above, setting the
flag may not make the debugging experience much better, and may actually
make it worse in cases where the variable actually is on the stack and
the more complicated analysis doesn't realize it.

A number of changes are included:
- Add a new pseudo-instruction, RegKill, which indicates that the value
in the register has been clobbered.
- Adjust regalloc to emit RegKills in the right places. Significantly,
this means that phis are mixed with StoreReg and RegKills after
regalloc.
- Track variable decomposition in ssa.LocalSlots.
- After the SSA backend is done, analyze the result and build location
lists for each LocalSlot.
- After assembly is done, update the location lists with the assembled
PC offsets, recompose variables, and build DWARF location lists. Emit the
list as a new linker symbol, one per function.
- In the linker, aggregate the location lists into a .debug_loc section.

TODO:
- currently disabled for non-X86/AMD64 because there are no data tables.

go build -toolexec 'toolstash -cmp' -a std succeeds.

With -dwarflocationlists false:
before: f02812195637909ff675782c0b46836a8ff01976
after:  06f61e8112a42ac34fb80e0c818b3cdb84a5e7ec
benchstat -geomean  /tmp/220352263 /tmp/621364410
completed   15 of   15, estimated time remaining 0s (eta 3:52PM)
name        old time/op       new time/op       delta
Template          199ms ± 3%        198ms ± 2%     ~     (p=0.400 n=15+14)
Unicode          96.6ms ± 5%       96.4ms ± 5%     ~     (p=0.838 n=15+15)
GoTypes           653ms ± 2%        647ms ± 2%     ~     (p=0.102 n=15+14)
Flate             133ms ± 6%        129ms ± 3%   -2.62%  (p=0.041 n=15+15)
GoParser          164ms ± 5%        159ms ± 3%   -3.05%  (p=0.000 n=15+15)
Reflect           428ms ± 4%        422ms ± 3%     ~     (p=0.156 n=15+13)
Tar               123ms ±10%        124ms ± 8%     ~     (p=0.461 n=15+15)
XML               228ms ± 3%        224ms ± 3%   -1.57%  (p=0.045 n=15+15)
[Geo mean]        206ms             377ms       +82.86%

name        old user-time/op  new user-time/op  delta
Template          292ms ±10%        301ms ±12%     ~     (p=0.189 n=15+15)
Unicode           166ms ±37%        158ms ±14%     ~     (p=0.418 n=15+14)
GoTypes           962ms ± 6%        963ms ± 7%     ~     (p=0.976 n=15+15)
Flate             207ms ±19%        200ms ±14%     ~     (p=0.345 n=14+15)
GoParser          246ms ±22%        240ms ±15%     ~     (p=0.587 n=15+15)
Reflect           611ms ±13%        587ms ±14%     ~     (p=0.085 n=15+13)
Tar               211ms ±12%        217ms ±14%     ~     (p=0.355 n=14+15)
XML               335ms ±15%        320ms ±18%     ~     (p=0.169 n=15+15)
[Geo mean]        317ms             583ms       +83.72%

name        old alloc/op      new alloc/op      delta
Template         40.2MB ± 0%       40.2MB ± 0%   -0.15%  (p=0.000 n=14+15)
Unicode          29.2MB ± 0%       29.3MB ± 0%     ~     (p=0.624 n=15+15)
GoTypes           114MB ± 0%        114MB ± 0%   -0.15%  (p=0.000 n=15+14)
Flate            25.7MB ± 0%       25.6MB ± 0%   -0.18%  (p=0.000 n=13+15)
GoParser         32.2MB ± 0%       32.2MB ± 0%   -0.14%  (p=0.003 n=15+15)
Reflect          77.8MB ± 0%       77.9MB ± 0%     ~     (p=0.061 n=15+15)
Tar              27.1MB ± 0%       27.0MB ± 0%   -0.11%  (p=0.029 n=15+15)
XML              42.7MB ± 0%       42.5MB ± 0%   -0.29%  (p=0.000 n=15+15)
[Geo mean]       42.1MB            75.0MB       +78.05%

name        old allocs/op     new allocs/op     delta
Template           402k ± 1%         398k ± 0%   -0.91%  (p=0.000 n=15+15)
Unicode            344k ± 1%         344k ± 0%     ~     (p=0.715 n=15+14)
GoTypes           1.18M ± 0%        1.17M ± 0%   -0.91%  (p=0.000 n=15+14)
Flate              243k ± 0%         240k ± 1%   -1.05%  (p=0.000 n=13+15)
GoParser           327k ± 1%         324k ± 1%   -0.96%  (p=0.000 n=15+15)
Reflect            984k ± 1%         982k ± 0%     ~     (p=0.050 n=15+15)
Tar                261k ± 1%         259k ± 1%   -0.77%  (p=0.000 n=15+15)
XML                411k ± 0%         404k ± 1%   -1.55%  (p=0.000 n=15+15)
[Geo mean]         439k              755k       +72.01%

name        old text-bytes    new text-bytes    delta
HelloSize         694kB ± 0%        694kB ± 0%   -0.00%  (p=0.000 n=15+15)

name        old data-bytes    new data-bytes    delta
HelloSize        5.55kB ± 0%       5.55kB ± 0%     ~     (all equal)

name        old bss-bytes     new bss-bytes     delta
HelloSize         133kB ± 0%        133kB ± 0%     ~     (all equal)

name        old exe-bytes     new exe-bytes     delta
HelloSize        1.04MB ± 0%       1.04MB ± 0%     ~     (all equal)

Change-Id: I991fc553ef175db46bb23b2128317bbd48de70d8
Reviewed-on: https://go-review.googlesource.com/41770
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
2017-07-27 20:19:44 +00:00
Ian Lance Taylor 39c07ce9e5 cmd/link: set ELF CPIC bit in mips64 objects
We already set it for mips32 objects. The native ELF linker warns when
linking PIC objects with non-PIC objects. Our objects are PIC, but we
were not marking them as such.

Fixes #20243.

Change-Id: Ifab131200b263e4c72cf81f7b131a65ac02a13a9
Reviewed-on: https://go-review.googlesource.com/42710
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-05-04 20:35:56 +00:00
Michael Hudson-Doyle be2ee2a4b4 cmd/internal/objabi, cmd/link: move linker-only symkind values into linker
Many (most!) of the values of objapi.SymKind are used only in the linker, so
this creates a separate cmd/link/internal/ld.SymKind type, removes most values
from SymKind and maps one to the other when reading object files in the linker.

Two of the remaining objapi.SymKind values are only checked for, never set and
so will never be actually found but I wanted to keep this to the most
mechanical change possible.

Change-Id: I4bbc5aed6713cab3e8de732e6e288eb77be0474c
Reviewed-on: https://go-review.googlesource.com/40985
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-04-27 21:56:12 +00:00
Matthew Dempsky 1e3570ac86 cmd/internal/objabi: extract shared functionality from obj
Now only cmd/asm and cmd/compile depend on cmd/internal/obj. Changing
the assembler backends no longer requires reinstalling cmd/link or
cmd/addr2line.

There's also now one canonical definition of the object file format in
cmd/internal/objabi/doc.go, with a warning to update all three
implementations.

objabi is still something of a grab bag of unrelated code (e.g., flag
and environment variable handling probably belong in a separate "tool"
package), but this is still progress.

Fixes #15165.
Fixes #20026.

Change-Id: Ic4b92fac7d0d35438e0d20c9579aad4085c5534c
Reviewed-on: https://go-review.googlesource.com/40972
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
2017-04-19 00:00:09 +00:00
Michael Hudson-Doyle 743fe0697d cmd/link: replace Segment's linked list of Sections with a slice
Just noticed this in passing.

Change-Id: I58fa828ef58598209ed4cbe4abc6f9f02ffc4844
Reviewed-on: https://go-review.googlesource.com/40896
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2017-04-18 21:24:32 +00:00
Joel Sing 9417c022c6 cmd/link,runtime/cgo: enable PT_TLS generation on OpenBSD
OpenBSD 6.0 and later have support for PT_TLS in ld.so(1). Now that OpenBSD
6.1 has been released, OpenBSD 5.9 is no longer officially supported and Go
can start generating PT_TLS for OpenBSD cgo binaries. This also allows us
to remove the workarounds in the OpenBSD cgo runtime.

This change also removes the environ and progname exports - these are now
provided directly by ld.so(1) itself.

Fixes #19932

Change-Id: I42e75ef9feb5dcd4696add5233497e3cbc48ad52
Reviewed-on: https://go-review.googlesource.com/40331
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-04-11 16:33:16 +00:00
Vladimir Stefanovic a3b670e333 cmd/link: add external linking support for GOARCH=mips{,le}
Fixes #17792.

Change-Id: If4f24455eec0edb3b221aef6777a681f6c768866
Reviewed-on: https://go-review.googlesource.com/34313
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-12-14 23:51:55 +00:00
Brad Fitzpatrick 4c4201f0e2 all: make spelling consistent
Fixes #17938

Change-Id: Iad12155f4976846bd4a9a53869f89e40e5b3deb3
Reviewed-on: https://go-review.googlesource.com/34147
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
2016-12-08 23:22:37 +00:00
David Crawshaw 348a7c5397 cmd/link: hash packages after loading all symbols
Conditioning on the plugin.Open symbol existing before loading all
symbols means sometimes some packages don't have a hash value.

Fixes #17928

Change-Id: I2722449aa58eca08a25117d3ce976f11f805b5ac
Reviewed-on: https://go-review.googlesource.com/33925
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-12-06 14:07:40 +00:00
Vladimir Stefanovic 76d8e60451 cmd/link: add support for GOARCH=mips{,le}
Only internal linking without cgo is supported for now.

Change-Id: I772d2ba496a613c78bee7e93f29e9538e6407bdc
Reviewed-on: https://go-review.googlesource.com/31481
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2016-11-08 19:58:09 +00:00
Vladimir Stefanovic 585a0b03b2 cmd/link/internal/ld: add support for GOARCH=mips{,le}
Change-Id: Ida214ccc5858969ea60abb0787f4d98bab4336d6
Reviewed-on: https://go-review.googlesource.com/31480
TryBot-Result: Gobot Gobot <gobot@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2016-11-04 19:27:35 +00:00
Russ Cox 8419c85eaa runtime, cmd/link: fix netbsd/arm EABI support
Fixes reported by oshimaya (see #13806).

Fixes #13806.

Change-Id: I9b659ab918a34bc5f7c58f3d7f59058115b7f776
Reviewed-on: https://go-review.googlesource.com/31651
Reviewed-by: Minux Ma <minux@golang.org>
2016-10-24 15:23:13 +00:00
Shawn Walker-Salas f373bf1eb9 cmd/link: non-executable stack support for Solaris
Support the tagging of binaries created with the internal linker
on Solaris as having a non-executable stack by writing a PT_SUNWSTACK
program header.

Fixes #16074

Change-Id: I3888f2153083385d04a52f341570f93e5738b276
Reviewed-on: https://go-review.googlesource.com/24142
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2016-10-12 06:41:25 +00:00
Lynn Boger b4efd09d18 cmd/link: split large elf text sections on ppc64x
Some applications built with Go on ppc64x with external linking
can fail to link with relocation truncation errors if the elf
text section that is generated is larger than 2^26 bytes and that
section contains a call instruction (bl) which calls a function
beyond the limit addressable by the 24 bit field in the
instruction.

This solution consists of generating multiple text sections where
each is small enough to allow the GNU linker to resolve the calls
by generating long branch code where needed.  Other changes were added
to handle differences in processing when multiple text sections exist.

Some adjustments were required to the computation of a method's address
when using the method offset table when there are multiple text sections.

The number of possible section headers was increased to allow for up
to 128 text sections.  A test case was also added.

Fixes #15823.

Change-Id: If8117b0e0afb058cbc072258425a35aef2363c92
Reviewed-on: https://go-review.googlesource.com/27790
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-09-21 20:23:49 +00:00
Michael Hudson-Doyle 836a3ae663 cmd/link: remove more unused ctxt parameters
This time in elf.go.

Change-Id: Ifaf71742ebbc9aadc8606c39ea2d417ae5cc7e0d
Reviewed-on: https://go-review.googlesource.com/29450
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-09-20 04:21:16 +00:00
Michael Hudson-Doyle 6383709272 cmd/link: remove now-unused ctxt arguments from a few functions
Specifically Addstring, Addbytes and Symgrow.

Change-Id: Ia74093bfcf9f360bf223accbc8feef54a7f059c9
Reviewed-on: https://go-review.googlesource.com/29348
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-09-20 04:13:16 +00:00
Michael Hudson-Doyle 324f6ab48c cmd/link: use ctxt.{Lookup,ROLookup} in favour of function versions of same
Done with two eg templates:

package p

import (
	"cmd/link/internal/ld"
)

func before(ctxt *ld.Link, name string, v int) *ld.Symbol {
	return ld.Linklookup(ctxt, name, v)
}
func after(ctxt *ld.Link, name string, v int) *ld.Symbol {
	return ctxt.Syms.Lookup(name, v)
}

package p

import (
	"cmd/link/internal/ld"
)

func before(ctxt *ld.Link, name string, v int) *ld.Symbol {
	return ld.Linkrlookup(ctxt, name, v)
}
func after(ctxt *ld.Link, name string, v int) *ld.Symbol {
	return ctxt.Syms.ROLookup(name, v)
}

Change-Id: I00647dbf62294557bd24c29ad1f108fc786335f1
Reviewed-on: https://go-review.googlesource.com/29343
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-09-20 04:12:43 +00:00
Michael Hudson-Doyle d41a7f77c5 cmd/link: do not directly embed Symbols in Link
Mostly done with sed.

Change-Id: Ic8c534a3fdd332b5420d062ee85bb77a30ad1efb
Reviewed-on: https://go-review.googlesource.com/29346
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-09-20 04:12:28 +00:00
David Crawshaw 1d3fae461c cmd/link: remove Cursym
Change-Id: I58253a6cd2d77a9319c0783afb0d92cd5a88a7f7
Reviewed-on: https://go-review.googlesource.com/29370
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Michael Hudson-Doyle <michael.hudson@canonical.com>
2016-09-20 02:42:16 +00:00
David Crawshaw 5a597e2d29 cmd/link: replace ld.Link.Diag with ld.Errorf
Instead of using ctxt.Cursym, Errorf takes an explicit *Symbol
parameter. This removes most uses of Cursym and means the *Link
context object is needed in fewer parts of the linker.

All transformations done manually, as wiring Cursym is tricky.

Change-Id: Ief88b00b73904224675c0035684c3a84c19249d7
Reviewed-on: https://go-review.googlesource.com/29369
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Michael Hudson-Doyle <michael.hudson@canonical.com>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-09-20 02:36:39 +00:00