Commit graph

84 commits

Author SHA1 Message Date
Jeremy Faller
7fe3f30bbb Revert "[dev.link] cmd/link: remove buffered file I/O from OutBuf"
This reverts commit b2def42d9e.

Reason for revert: trybots failing

Change-Id: I920be6d8de158b1e513154ac0eb0c8fa0cffa9f4
Reviewed-on: https://go-review.googlesource.com/c/go/+/228657
Reviewed-by: Than McIntosh <thanm@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2020-04-17 13:47:03 +00:00
Jeremy Faller
b2def42d9e [dev.link] cmd/link: remove buffered file I/O from OutBuf
Change-Id: I72b1e57631fe4a31597fd0452ee1beb14378febb
Reviewed-on: https://go-review.googlesource.com/c/go/+/228317
Run-TryBot: Jeremy Faller <jeremy@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
2020-04-16 19:53:10 +00:00
Cherry Zhang
53a2a6a7fc [dev.link] all: merge branch 'master' into dev.link
Clean merge.

Change-Id: Ic3634fa450e42635e2daafb53b7dedc6c954d072
2020-04-10 13:50:52 -04:00
Austin Clements
f7e6ab44b4 all: remove scattered remnants of darwin/arm
This removes all conditions and conditional code (that I could find)
that depended on darwin/arm.

Fixes #35439 (since that only happened on darwin/arm)
Fixes #37611.

Change-Id: Ia4c32a5a4368ed75231075832b0b5bfb1ad11986
Reviewed-on: https://go-review.googlesource.com/c/go/+/227198
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2020-04-08 18:35:49 +00:00
Cherry Zhang
dc6d452615 [dev.link] cmd/link: gofmt
I somehow messed up my local environment for the pre-commit hook.
Fix the format.

Change-Id: I6161ad1fce7714e8f311be5315d854f8c9bd7664
Reviewed-on: https://go-review.googlesource.com/c/go/+/227579
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
2020-04-08 16:30:09 +00:00
Cherry Zhang
850c602ed6 [dev.link] cmd/link: convert text address assignment to new style
Implement text address assignment and trampoline generation using
the loader.

Note: the trampoline insertion part doesn't actually work. It
also needs to propagate Aux symbols for external symbols in
LoadFull.  But it won't be needed after converting pclntab
generation, so I'll leave it out for now. This could break
linking large binaries on PPC64 and ARM.

Change-Id: Ie46a35b25d7c027983dd877207cfa8f67c32530b
Reviewed-on: https://go-review.googlesource.com/c/go/+/227482
Reviewed-by: Than McIntosh <thanm@google.com>
2020-04-08 15:32:39 +00:00
Than McIntosh
8e457c865d [dev.link] cmd/link: begin converting gentext to loader APIs
Begin the job of converting the linker's "gentext" phase over to use
loader APIs. This patch includes most architectures except for s390x
and PPC (these will be added in subsequent patches, since they require
a couple of loader changes first).

Change-Id: Ic7f55c207dcdbbba657330ef007a72ff7c837416
Reviewed-on: https://go-review.googlesource.com/c/go/+/227017
Reviewed-by: Jeremy Faller <jeremy@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2020-04-06 14:56:10 +00:00
Jeremy Faller
6506cf1981 [dev.link] cmd/link: make asmb parallel across all platforms
Numbers for x86:

Asmb                      54.8ms ±15%    12.1ms ±28%   -78.02%  (p=0.000 n=10+10)
TotalTime                  545ms ± 3%     515ms ± 4%    -5.42%  (p=0.000 n=10+10)

Change-Id: I8fc17f7ccdf83fbd70cf7d27b44f41f9db9c9922
Reviewed-on: https://go-review.googlesource.com/c/go/+/224419
Run-TryBot: Jeremy Faller <jeremy@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2020-03-30 21:21:28 +00:00
Cherry Zhang
4ba39d6a58 [dev.link] cmd/link: pass loader to relocation functions
It is needed in Xcoffadddynrel. And it will be needed once we
move more things to new style (the sym.Symbol parameters will
also need to change).

Change-Id: Ie12683f9b44e21f1e6ea711bf2f4c5c32282e5b3
Reviewed-on: https://go-review.googlesource.com/c/go/+/225203
Reviewed-by: Jeremy Faller <jeremy@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
2020-03-25 15:21:43 +00:00
Jeremy Faller
5d9cdbb840 [dev.link] cmd/link: remove *Link from some arch functions
Change-Id: Ia7f9a999af5285885987b83a877b205b274342a6
Reviewed-on: https://go-review.googlesource.com/c/go/+/222306
Run-TryBot: Jeremy Faller <jeremy@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
2020-03-19 19:25:28 +00:00
Jeremy Faller
bf5dc7af0f [dev.link] cmd/link: eliminate usage of *Link in arch funcs
Change-Id: I10e6b266ff3a1238d1b86a9b39debb13f5a04e55
Reviewed-on: https://go-review.googlesource.com/c/go/+/222159
Run-TryBot: Jeremy Faller <jeremy@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
2020-03-19 19:25:15 +00:00
Cherry Zhang
a3e965ce8a [dev.link] cmd/link: convert doelf to new style
Change-Id: I448fe632ae73ddcb79c05793c96f48e358060305
Reviewed-on: https://go-review.googlesource.com/c/go/+/222977
Reviewed-by: Than McIntosh <thanm@google.com>
2020-03-11 23:24:00 +00:00
Jeremy Faller
cb4c84bd9a [dev.link] cmd/link: add Target and ArchSyms to arch functions
Change-Id: Iab9e5bd8115e81a10067e44397cbe34addda1b63
Reviewed-on: https://go-review.googlesource.com/c/go/+/222064
Run-TryBot: Jeremy Faller <jeremy@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
2020-03-11 14:30:54 +00:00
Jeremy Faller
8db73599d3 [dev.link] cmd/link: remove *Link from elf functions
dodata is a pile of dependencies on *Link. Pull some of these
dependencies out, and tighten up the visibility on the functions.

Change-Id: Id213f19ae7b63dd246ddb47b77ffde99f615aa80
Reviewed-on: https://go-review.googlesource.com/c/go/+/222061
Reviewed-by: Than McIntosh <thanm@google.com>
2020-03-09 20:21:03 +00:00
Jeremy Faller
4ab7ab54b0 [dev.link] cmd/link: remove *Link from architecture relocers
Also correct a few places I hadn't switched over to Target from *Link
context.

Change-Id: I6de6b39723762de3fa5f8d12800085421aca76fb
Reviewed-on: https://go-review.googlesource.com/c/go/+/220840
Reviewed-by: Than McIntosh <thanm@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2020-03-04 18:55:08 +00:00
Jeremy Faller
b9642cbb8d [dev.link] cmd/link: add Target to relocation functions
We need to propogate Target through the relocation functions.

Change-Id: I1192d54a20a34569fd13c1511d2b21ebf2d1272e
Reviewed-on: https://go-review.googlesource.com/c/go/+/220839
Run-TryBot: Jeremy Faller <jeremy@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2020-03-03 15:09:44 +00:00
John Papandriopoulos
59a6847039 cmd/link: pass-through undefined call targets in external link mode
Allows Go asm calls referencing a function in a .syso file to be
passed through to the external linker, that would have otherwise
raised a "relocation target X not defined" error in cmd/link.

Fixes #33139

Change-Id: I2a8eb6063ebcd05fac96f141acf7652cf9189766
Reviewed-on: https://go-review.googlesource.com/c/go/+/198798
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2019-10-28 22:10:06 +00:00
nikita-vanyasin
c3e8a20a65 cmd/link/internal: eliminate all ld.Cputime() usages
Also a similar 'elapsed' function and its usages were deleted.

Fixes #19865.

Change-Id: Ib125365e69cf2eda60de64fa74290c8c7d1fd65a
Reviewed-on: https://go-review.googlesource.com/c/go/+/171730
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
2019-10-26 05:40:14 +00:00
Brad Fitzpatrick
07b4abd62e all: remove the nacl port (part 2, amd64p32 + toolchain)
This is part two if the nacl removal. Part 1 was CL 199499.

This CL removes amd64p32 support, which might be useful in the future
if we implement the x32 ABI. It also removes the nacl bits in the
toolchain, and some remaining nacl bits.

Updates #30439

Change-Id: I2475d5bb066d1b474e00e40d95b520e7c2e286e1
Reviewed-on: https://go-review.googlesource.com/c/go/+/200077
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2019-10-09 22:34:34 +00:00
Andrew Bonventre
1820cca7d7 Revert "cmd/link: load symbols from .syso in external link mode"
This reverts CL 186417.

Reason for revert: Broke darwin (10_14), linux (ppc), aix (ppc)

Updates #33139

Change-Id: I8bf3c817a96a0e57e45754a097cea7062b2fcdfd
Reviewed-on: https://go-review.googlesource.com/c/go/+/198177
Run-TryBot: Andrew Bonventre <andybons@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
2019-10-01 13:20:16 +00:00
John Papandriopoulos
5e514b76e2 cmd/link: load symbols from .syso in external link mode
Fix linking with a package having a .syso file in external link mode,
that would otherwise cause an error before executing the external
linker because it can't find symbols that are exported in the said
.syso file.

Fixes #33139

Change-Id: Id3ee737fba1c6f1e37910593dfedf9c84486d398
Reviewed-on: https://go-review.googlesource.com/c/go/+/186417
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2019-10-01 00:02:11 +00:00
Cherry Zhang
b2f94d3e88 cmd/link: mmap output file
Use mmap for writing most of the output file content,
specifically, the sections and segments. After layout, we
already know the sizes and file offsets for the sections and
segments. So we can just write the bytes by copying to a mmap'd
backing store.

The writing of the output file is split into two parts. The first
part writes the sections and segments to the mmap'd region. The
second part writes some extra content, for which we don't know
the size, so we use direct file IO.

This is in preparation for mmap'ing input files read-only.

Change-Id: I9f3b4616a9f96bfd5c940d74c50aacd6d330f7d2
Reviewed-on: https://go-review.googlesource.com/c/go/+/170738
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2019-04-19 18:24:44 +00:00
erifan01
3b37ff453e cmd/link: increase the reserved space for ELF relocations
Currently the offset values of ELF relocations and Macho relocations
are 256 and 512 respectively, which means that the space reserved for
ELF relocations is only 256. But AARCH64 has more than 256 ELF relocation
types, in fact the maximum AARCH64 ELF relocation type recorded in file
src/debug/elf/elf.go is 1032 currently. So this CL increases the offset
of Macho relocations to 2048 to leave enough space for AARCH64 ELF
relocations.

Change-Id: I784ac38aeb3e102ac7825f6d621086849c8d3146
Reviewed-on: https://go-review.googlesource.com/c/go/+/172497
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2019-04-17 23:31:28 +00:00
Than McIntosh
f78cc1324a cmd/link: move Plt, Got fields in sym.Symbol to cold section
The sym.Symbol 'Plt' and 'Got' field are used only with cgo and/or
external linking and are not needed for most symbols. Relocate them to
sym.AuxSymbol so as to shrink the main Symbol struct.

Updates #26186

Change-Id: I170d628a760be300a0c1f738f0998970e91ce3d6
Reviewed-on: https://go-review.googlesource.com/125478
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2018-08-30 12:35:10 +00:00
Jordan Rhee
aa311fecda cmd/link: support windows/arm
Enable the Go linker to generate executables for windows/arm.

Generates PE relocation tables, which are used by Windows to
dynamically relocate the Go binary in memory. Windows on ARM
requires all modules to be relocatable, unlike x86/amd64 which are
permitted to have fixed base addresses.

Updates #26148

Change-Id: Ie63964ff52c2377e121b2885e9d05ec3ed8dc1cd
Reviewed-on: https://go-review.googlesource.com/125648
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-08-21 22:11:05 +00:00
isharipo
328adf9d62 cmd/link: fewer allocs in ld.Arch.Archreloc
Archreloc had this signature:

	func(*Link, *sym.Reloc, *sym.Symbol, *int64) bool

The last *int64 argument is used as out parameter.
Passed valus could be allocated on stack, but escape analysis
fails here, leading to high number of unwanted allocs.

If instead 4th arg is passed by value, and modified values is returned,
no problems with allocations arise:

	func(*Link, *sym.Reloc, *sym.Symbol, int64) (int64, bool)

There are 2 benefits:
1. code becomes more readable.
2. less allocations.

For linking "hello world" example from net/http:

	name      old time/op  new time/op  delta
	Linker-4   530ms ± 2%   520ms ± 2%  -1.83%  (p=0.001 n=17+16)

It's top 1 in alloc_objects from memprofile:

	flat   flat%  sum%       cum    cum%
	229379 33.05% 33.05%     229379 33.05%  cmd/link/internal/ld.relocsym
	...

list relocsym:

	229379     229379 (flat, cum) 33.05% of Total
	229379     229379    183:    var o int64

After the patch, ~230k of int64 allocs (~ 1.75mb) removed.

Passes toolshash-check (toolstash cmp).

Change-Id: I25504fe27967bcff70c4b7338790f3921d15473d
Reviewed-on: https://go-review.googlesource.com/113637
Run-TryBot: Iskander Sharipov <iskander.sharipov@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-08-20 22:10:31 +00:00
Elias Naur
c8d07295c5 cmd/link,runtime: move syscalls to libc on iOS
This CL is the darwin/arm and darwin/arm64 equivalent to CL 108679,
110215, 110437, 110438, 111258, 110655.

Updates #17490

Change-Id: Ia95b27b38f9c3535012c566f17a44b4ed26b9db6
Reviewed-on: https://go-review.googlesource.com/111015
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2018-05-21 20:35:00 +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
Kunpei Sakai
0c471dfae2 cmd: avoid unnecessary type conversions
CL generated mechanically with github.com/mdempsky/unconvert.

Also updated cmd/compile/internal/ssa/gen/*.rules manually.

Change-Id: If721ef73cf0771ae83ce7e2d11623fc8d9155768
Reviewed-on: https://go-review.googlesource.com/97075
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-02-26 20:22:06 +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
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
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
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
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
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
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
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
Cherry Zhang
c7e855658d cmd/link: trampoline support for external linking on ARM
all.bash passes with -debugtramp=2 (except the unavoidable
disassembly test as we change instructions). And successfully
build k8s.io/kubernetes/cmd/hyperkube in both internal linking
and external linking mode.

Fixes #17028.

Change-Id: Ic8fac6a394488155c5eba9215662db1c1086e24b
Reviewed-on: https://go-review.googlesource.com/31143
Reviewed-by: David Chase <drchase@google.com>
2016-10-17 21:38:06 +00:00
Cherry Zhang
7c431cb7f9 cmd/link: insert trampolines for too-far jumps on ARM
ARM direct CALL/JMP instruction has 24 bit offset, which can only
encodes jumps within +/-32M. When the target is too far, the top
bits get truncated and the program jumps wild.

This CL detects too-far jumps and automatically insert trampolines,
currently only internal linking on ARM.

It is necessary to make the following changes to the linker:
- Resolve direct jump relocs when assigning addresses to functions.
  this allows trampoline insertion without moving all code that
  already laid down.
- Lay down packages in dependency order, so that when resolving a
  inter-package direct jump reloc, the target address is already
  known. Intra-package jumps are assumed never too far.
- a linker flag -debugtramp is added for debugging trampolines:
    "-debugtramp=1 -v" prints trampoline debug message
    "-debugtramp=2"    forces all inter-package jump to use
                       trampolines (currently ARM only)
    "-debugtramp=2 -v" does both
- Some data structures are changed for bookkeeping.

On ARM, pseudo DIV/DIVU/MOD/MODU instructions now clobber R8
(unfortunate). In the standard library there is no ARM assembly
code that uses these instructions, and the compiler no longer emits
them (CL 29390).

all.bash passes with -debugtramp=2, except a disassembly test (this
is unavoidable as we changed the instruction).

TBD: debug info of trampolines?

Fixes #17028.

Change-Id: Idcce347ea7e0af77c4079041a160b2f6e114b474
Reviewed-on: https://go-review.googlesource.com/29397
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-10-11 13:35:33 +00:00
Alberto Donizetti
590f3f0c9d cmd/compile: fix misaligned comments
Realign multi-line comments that got misaligned by the c->go
conversion.

Change-Id: I584b902e95cf588aa14febf1e0b6dfa499c303c2
Reviewed-on: https://go-review.googlesource.com/29871
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-09-27 14:00:39 +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