Commit graph

52 commits

Author SHA1 Message Date
Cherry Mui
3b51581261 cmd/link: replace function pointers to static calls in loadelf
When transitioning between the old object loader and the new
object loader, to support both we made loadelf to take symbol
loading functions as function pointers. Now we only have the new
object loader. Change the function pointers back to static calls.

Change-Id: Ia623a6010376a3d7c0be5eacae002144d956f28a
Reviewed-on: https://go-review.googlesource.com/c/go/+/564635
Reviewed-by: Than McIntosh <thanm@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
2024-02-16 15:12:12 +00:00
Guoqi Chen
39d3c4ad35 debug/elf,cmd/link: add additional relocations for loong64
The Linker Relaxation feature on Loong64 is already supported in binutils 2.41.
The intermediate code generated after enabling this feature introduces three
reloc types R_LARCH_B26, R_LARCH_ADD32 and R_LARCH_SUB32.

The other relocation types are not currently used when running all.bash, but
in order to avoid the host tool chain making the decision to use it we don't
have to catch it every time.

The LoongArch ABI at here:
https://github.com/loongson/la-abi-specs/blob/release/la-abi.adoc

Corresponding binutils implementation:
https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=be1ebb6710a8f707bd4b0eecbd00f4f4964050e5
https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=1b6fccd28db14fffe75ff6755307047ef932c81e

Fixes #63725

Change-Id: I891115cfdbcf785ab494c881d5f9d1bf8748da8b
Reviewed-on: https://go-review.googlesource.com/c/go/+/537615
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Meidan Li <limeidan@loongson.cn>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
2023-11-02 19:46:03 +00:00
limeidan
ed26e2fe34 cmd/link/internal/loadelf: correct the relocation size of R_LARCH_64
Change-Id: If3eaca8b92e8f5265c7763d13021a6353b9df9b6
Reviewed-on: https://go-review.googlesource.com/c/go/+/528455
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
Reviewed-by: abner chenc <chenguoqi@loongson.cn>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
2023-09-14 17:34:12 +00:00
Joel Sing
1152615d20 debug/elf,cmd/link: add additional MIPS64 relocation type
Add R_MIPS_PC32 which is a 32 bit PC relative relocation.

These are produced by LLVM on mips64.

Fixes #61974

Change-Id: I7b6c6848e40249e6d5ea474ea53c9d7e3ab23f88
Reviewed-on: https://go-review.googlesource.com/c/go/+/469395
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Joel Sing <joel@sing.id.au>
Reviewed-by: Junxian Zhu <zhujunxian@oss.cipunited.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
2023-09-08 04:32:10 +00:00
Joel Sing
e68c027204 cmd/internal/obj/riscv,cmd/link: add support for internal cgo linking on riscv64
Make it possible to internally link cgo on riscv64, which also adds
support for SDYNIMPORT calls without external linking being required.

This reduces the time of an ./all.bash run on a Sifive Hifive Unleashed by
approximately 20% (~140 minutes down to ~110 minutes).

Change-Id: I43f1348de31672718ae8676cc82f6fdc1dfee054
Reviewed-on: https://go-review.googlesource.com/c/go/+/431104
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Run-TryBot: Joel Sing <joel@sing.id.au>
Reviewed-by: Than McIntosh <thanm@google.com>
2023-08-23 05:58:20 +00:00
Paul E. Murphy
e946f0e1ff cmd/link: support R_PPC64_REL24_P9NOTOC
This can be treated identically to R_PPC64_REL24_NOTOC as stubs
are generated based on GOPPC64 and -buildmode.

Change-Id: I3c42a9bf3c08d107fb656e6bf59b2307783bd9af
Reviewed-on: https://go-review.googlesource.com/c/go/+/497915
Reviewed-by: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Lynn Boger <laboger@linux.vnet.ibm.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Run-TryBot: Paul Murphy <murp@ibm.com>
2023-05-31 20:55:01 +00:00
Paul E. Murphy
3c46d8f511 cmd/link: load external ELF PPC64 objects which set st_other=1
This indicates the symbol does not use or preserve the TOC pointer in
R2. Likewise, it does not have a distinct local entry point. This
happens when gcc compiles an object with -mcpu=power10.

Recycle the SymLocalentry field of a text symbol to pass through this
hint as the bogus value 1 (A valid offset must be a multiple of 4
bytes), and update the usage to check and generate errors further into
the linking process. This matches the behavior of st_other as used by
ELFv2.

Change-Id: Ic89ce17b57f400ab44213b21a3730a98c7cdf842
Reviewed-on: https://go-review.googlesource.com/c/go/+/490295
Run-TryBot: Paul Murphy <murp@ibm.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
2023-04-28 21:26:08 +00:00
Paul E. Murphy
d816f85f78 cmd/link/internal/loadelf: set AttrExternal on text section symbols
PPC64 processes external object relocations against the section
symbols. This needs to be set correctly to determine the type of
PLT stub to generate when both Go and External code make PLT calls.

Change-Id: I5abdd5a0473866164083c33e80324dffcc1707f0
Reviewed-on: https://go-review.googlesource.com/c/go/+/488895
Reviewed-by: Than McIntosh <thanm@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Run-TryBot: Paul Murphy <murp@ibm.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
2023-04-26 15:25:47 +00:00
Joel Sing
bc73996fac cmd/link/internal/loadelf: add additional relocations for riscv64
These relocations are produced by clang/llvm.

Change-Id: I4820e7ed805d1b7341023b263c167a285ca32cf5
Reviewed-on: https://go-review.googlesource.com/c/go/+/431755
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Run-TryBot: Joel Sing <joel@sing.id.au>
TryBot-Result: Gopher Robot <gobot@golang.org>
2022-09-28 16:43:13 +00:00
Paul E. Murphy
edd1273b84 cmd/link: refactor usage of SymLocalentry helper functions
PPC64 ELFv2 uses the st_other field of a symbol to specify an offset
from the global entry point to its local entry point. Similarly, some
values (i.e 1) may also require additional linker support which is
missing today.

For now, generate an error if we encounter unsupported local entry
values on PPC64, and update the Localentry values to use bytes, not
32b instruction words.

Similarly, ELFv2 1.5 also updates the wording of values 2-6. They
now map to a specific number of bytes.

Change-Id: Id1b71c3b0fea982bdcfb7eac91d9f93e04ae43f9
Reviewed-on: https://go-review.googlesource.com/c/go/+/431876
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Run-TryBot: Paul Murphy <murp@ibm.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
2022-09-27 17:29:05 +00:00
Paul E. Murphy
7fda98a8d9 cmd/link: support -fno-plt compiled gcc objects on ppc64le
This is the initial trivial implemenation. Further improvements can be
made for local calls.

A test is added, but the -fno-plt option is ignored by gcc if binutils
does not support inline plt relocations, so the test is effectively
skipped on such hosts.

Fixes #53345

Change-Id: Ibf31c26b1a8551c942b21019df8782c00b7a563e
Reviewed-on: https://go-review.googlesource.com/c/go/+/412714
Reviewed-by: Lynn Boger <laboger@linux.vnet.ibm.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Run-TryBot: Paul Murphy <murp@ibm.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Jenny Rakoczy <jenny@golang.org>
Auto-Submit: Jenny Rakoczy <jenny@golang.org>
Run-TryBot: Jenny Rakoczy <jenny@golang.org>
2022-09-15 21:11:05 +00:00
WANG Xuerui
2c5b174616 cmd/link: recognize the new R_LARCH_32_PCREL type on loong64
Due to the latest binutils change [1], at least for certain 32-bit
relocs in .eh_frame section, this new type of relocation record is
emitted, leading to breakage on systems with bleeding-edge toolchain
when trying to link with object(s) with such new-style relocs.

Simply treating it the same as the existing reloc types seems enough.

Fixes #54222

[1]: https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=f09482a8747b6fd4c2d59a6a64677d3a3fe1e092

Change-Id: I876d6711d5d4a674bead37e57f9503f1622d1136
Reviewed-on: https://go-review.googlesource.com/c/go/+/420983
Run-TryBot: Dmitri Shuralyov <dmitshur@golang.org>
Reviewed-by: abner chenc <chenguoqi@loongson.cn>
Auto-Submit: Dmitri Shuralyov <dmitshur@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
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Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
2022-08-15 13:11:25 +00:00
Xiaodong Liu
cc4957a5f6 cmd/link: support linker for linux/loong64
The basic arch-specific hooks are implemented, which
are used for internal and external linker.

Contributors to the loong64 port are:
  Weining Lu <luweining@loongson.cn>
  Lei Wang <wanglei@loongson.cn>
  Lingqin Gong <gonglingqin@loongson.cn>
  Xiaolin Zhao <zhaoxiaolin@loongson.cn>
  Meidan Li <limeidan@loongson.cn>
  Xiaojuan Zhai <zhaixiaojuan@loongson.cn>
  Qiyuan Pu <puqiyuan@loongson.cn>
  Guoqi Chen <chenguoqi@loongson.cn>

This port has been updated to Go 1.15.6:
  https://github.com/loongson/go

Updates #46229

Change-Id: I4680eb0635dd0fa3d6ea8348a2488da9c7e33d3b
Reviewed-on: https://go-review.googlesource.com/c/go/+/349514
Reviewed-by: Cherry Mui <cherryyz@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Run-TryBot: Ian Lance Taylor <iant@google.com>
2022-05-17 17:54:33 +00:00
Cherry Mui
2049649e8b cmd/link: fix handling of visibility hidden symbols
There is a TODO comment that checking hidden visibility is
probably not the right thing to do. I think it is indeed not. Here
we are not referencing symbols across DSO boundaries, just within
an executable binary. The hidden visibility is for references from
another DSO. So it doesn't actually matter.

This makes cgo internal linking tests work on ARM64 with newer
GCC. It failed and was disabled due to a visibility hidden symbol
in libgcc.a that we didn't handle correctly. Specifically, the
problem is that we didn't mark visibility hidden symbol references
SXREF, which caused the loader to not think it is an unresolved
external symbol, which in turn made it not loading an object file
from the libgcc.a archive which contains the actual definition.
Later stage when we try to resolve the relocation, we couldn't
resolve it. Enable the test as it works now.

Fixes #39466.

Change-Id: I2759e3ae15e7a7a1ab9a820223b688ad894509ed
Reviewed-on: https://go-review.googlesource.com/c/go/+/404296
Reviewed-by: Than McIntosh <thanm@google.com>
Run-TryBot: Cherry Mui <cherryyz@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
2022-05-06 17:37:38 +00:00
Dmitry Vyukov
1ec51087e5 cmd/link/internal/loadelf: better error message for ignored symbols
Currently it's quite hard to debug these error messages about ignored symbols
because there are only some numbers and no symbol name. Add symbol name. Before:
135029: sym#952: ignoring symbol in section 11 (type 0)
After:
135029: sym#952 (_ZN11__sanitizer9SpinMutexC5Ev): ignoring symbol in section 11 (type 0)

Change-Id: I7fec50b5798068c74827376613be529803838c5a
Reviewed-on: https://go-review.googlesource.com/c/go/+/363034
Run-TryBot: Dmitry Vyukov <dvyukov@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Trust: Dmitry Vyukov <dvyukov@google.com>
2021-11-11 07:03:15 +00:00
korzhao
58490972c0 cmd/link: fix dead reference link
Change-Id: I0f53cc2b845f8a52fece2aaba1445a0ecb9cdc53
Reviewed-on: https://go-review.googlesource.com/c/go/+/341129
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Trust: Dmitri Shuralyov <dmitshur@golang.org>
2021-08-13 21:47:42 +00:00
Austin Clements
69262d4871 cmd/compile,cmd/link: resolve cgo symbols to the correct Go ABI
Currently, Go functions exported to cgo have some confusion around
ABIs that leads to crashes. The cmd/cgo-generated C code references an
exported Go wrapper function (which calls the underlying exported user
function). The linker resolves this reference to the ABI0 entry-point
to that Go wrapper function because all host object references are
currently assumed to be to version 0 of a symbol. This gets passed via
crosscall2 and winds its way to cgocallbackg1, which puts this ABI0
entry-point into a function value and calls it. Unfortunately,
function values always use the ABIInternal calling convention, so
calling this ABI0 entry-point goes poorly.

Fix this by threading definition ABIs through the cgo export mechanism
so the linker can resolve host object references (which have no
concept of multiple ABIs) to the correct Go symbol. This involves a
few pieces:

- The compiler extends the cgo_export_{static,dynamic} directives that
  get passed on to the linker with symbol definition ABIs.

- The linker parses the ABIs in the cgo_export_{static,dynamic}
  directives to look up the right symbol to apply export attributes to
  and put in the dynexp list.

- For internal linking, the linker's Loader structure tracks the right
  symbol (in particular the right ABI) to resolve host object
  references to, and we use this in all of the host object loaders.

- For external linking, we mangle only the non-ABIInternal symbols
  now, so the external linker is able to resolve the correct reference
  from host objects to Go symbols.

Updates #40724.

Change-Id: I70a0b1610596768c3f473745fa1a3e630afbf1a8
Reviewed-on: https://go-review.googlesource.com/c/go/+/309341
Trust: Austin Clements <austin@google.com>
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
2021-04-13 20:07:47 +00:00
Paul E. Murphy
975b097307 cmd/link: separate elf addend size from reloc size
The size of the field may be smaller than the addend,
such is the case with R_PPC64_TOC16_HA/LO and similar
relocations.

Add an extra return value to ldelf.relSize to account for
addend size which may be larger than the relocated field,
and fix the related ppc64 relocations.

Such relocs can be seen in large PIC blobs such
as the ppc64le race detector included with golang.

Change-Id: I457186fea5d0ec5572b9bbf79bb7fa21a36cc1b0
Reviewed-on: https://go-review.googlesource.com/c/go/+/303990
Run-TryBot: Paul Murphy <murp@ibm.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Lynn Boger <laboger@linux.vnet.ibm.com>
TryBot-Result: Go Bot <gobot@golang.org>
Trust: Lynn Boger <laboger@linux.vnet.ibm.com>
2021-03-24 14:52:14 +00:00
Paul E. Murphy
bd0fc0b9c3 cmd/link: preserve elf phdr flags when loading external objects
Preserve program header flags when passing them through loadelf.Load.
They shouldn't be coerced to 0 on non-ARM platforms which set them
such as ppc64le.

Change-Id: I022613356f910d812de2fc22eac949960eeb53b3
Reviewed-on: https://go-review.googlesource.com/c/go/+/300950
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Trust: Emmanuel Odeke <emmanuel@orijtech.com>
2021-03-16 14:20:35 +00:00
Meng Zhuo
31df4e3fcd cmd/link: add relocs type for mips64x
The race detector of llvm adds four reloc types even with -fPIC

elf.R_MIPS_CALL16
elf.R_MIPS_GPREL32
elf.R_MIPS_64
elf.R_MIPS_GOT_DISP

Change-Id: If73119dcba14ef74395273eb680f52a0aa853217
Reviewed-on: https://go-review.googlesource.com/c/go/+/270297
Trust: Meng Zhuo <mzh@golangcn.org>
Run-TryBot: Meng Zhuo <mzh@golangcn.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
2021-03-05 06:18:33 +00:00
Joel Sing
e508c1c67b cmd/link/internal/loadelf: support additional ELF relocations on mips64
LLVM on openbsd/mips64 generates R_MIPS_GOT_HI16 and R_MIPS_GOT_LO16 relocations,
so teach cmd/link/internal/loadelf about both of these.

Updates #43005

Change-Id: Ic45ea8b901d44dcbdbf355411ee434dcd7670a92
Reviewed-on: https://go-review.googlesource.com/c/go/+/275894
Trust: Joel Sing <joel@sing.id.au>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2020-12-11 08:18:17 +00:00
eric fang
1308f11897 cmd/link: add relocation type R_AARCH64_LDST16_ABS_LO12_NC for arm64
The linker already has R_AARCH64_LDST{8,32,64,128}_ABS_LO12_NC, some cgo tests require
 R_AARCH64_LDST16_ABS_LO12_NC, this CL adds this relocation type.

Fixes #42660

Change-Id: I9a5120cd872f5095c61175cb602427c6ab3225cc
Reviewed-on: https://go-review.googlesource.com/c/go/+/271017
Reviewed-by: eric fang <eric.fang@arm.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: eric fang <eric.fang@arm.com>
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Trust: eric fang <eric.fang@arm.com>
Trust: Benny Siegert <bsiegert@gmail.com>
2020-11-25 02:51:30 +00:00
Joel Sing
0b798c46cd cmd/link: add loadelf support for riscv64
Update #36641

Change-Id: I8618da30d8940a56d6cc86a37a2f54b31ee029e5
Reviewed-on: https://go-review.googlesource.com/c/go/+/263601
Trust: Joel Sing <joel@sing.id.au>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Joel Sing <joel@sing.id.au>
TryBot-Result: Go Bot <gobot@golang.org>
2020-10-29 18:26:42 +00:00
Than McIntosh
3c3cc19564 [dev.link] cmd/link: better naming for Loader container/subsym methods, part 1 of 2
Introduce a new loader method "AddInteriorSym" to be used when
establishing container/containee symbol relationships for host object
sub-symbols and GOT/dynamic sub-symbols.

Interior symbols are employed in situations where you have a
"container" or "payload" symbol that has content, and then a series of
"interior" sub-symbols that point into a portion of the container
symbol's content. Each interior symbol will typically have a useful
name / size / value, but no content of its own. From a symbol table
perspective the container symbol is anonymous, but the interior
symbols are added to the output symbol table.

Change-Id: I919ed5dbbfe2ef2c9a76214f7ea9b384a1be6297
Reviewed-on: https://go-review.googlesource.com/c/go/+/240508
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Jeremy Faller <jeremy@golang.org>
2020-07-06 22:56:23 +00:00
Meng Zhuo
9b9556f660 cmd/link: use definition from debug/elf for ldelf
Change-Id: I92d0fb3a244d0151fcc4b25a20913ad69a89f198
Reviewed-on: https://go-review.googlesource.com/c/go/+/224977
Run-TryBot: Meng Zhuo <mengzhuo1203@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2020-04-27 15:53:46 +00:00
Cherry Zhang
0505e8a3a3 [dev.link] cmd/link: use new-style Reloc accessors in loadelf
Change-Id: I9c283aa2631dc21c0567a0708b26cdf95a6dc9fb
Reviewed-on: https://go-review.googlesource.com/c/go/+/227897
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
2020-04-10 17:30:12 +00:00
Cherry Zhang
b1a19f3cc7 [dev.link] cmd/link: convert doxcoff to new style
Change-Id: Ic1e4ed6c14e049b1ba2f7c00f986433ab7ebe932
Reviewed-on: https://go-review.googlesource.com/c/go/+/225202
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
2020-03-25 15:20:40 +00:00
Jeremy Faller
9d673bf1db [dev.link] cmd/link: use RO memory (when avail) in elf loader
Recreation of CL 206139 in the new symbol hierarchy.

Change-Id: Ic20c5c1b5db8f7eadf4c6ee4638e3c1a4e10ef3a
Reviewed-on: https://go-review.googlesource.com/c/go/+/219317
Run-TryBot: Jeremy Faller <jeremy@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2020-02-18 15:48:03 +00:00
Cherry Zhang
112a7cb82c [dev.link] cmd/link: remove the second result of MakeSymbolUpdater
With unique global indices, MakeSymbolUpdater will not change the
symbol's index. So no need to return a new index.

Change-Id: I5b4fd6a0167cc74476880bbf4382c524ecde7721
Reviewed-on: https://go-review.googlesource.com/c/go/+/219227
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Jeremy Faller <jeremy@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
2020-02-13 16:56:56 +00:00
Cherry Zhang
ee04d45b8f [dev.link] all: merge branch 'master' into dev.link
It has been a while we have not done this.

Merge conflict resolution:
- deleted/rewritten code modified on master
  - CL 214286, ported in CL 217317
    (cmd/internal/obj/objfile.go)
  - CL 210678, it already includes a fix to new code
    (cmd/link/internal/ld/deadcode.go)
  - CL 209317, applied in this CL
    (cmd/link/internal/loadelf/ldelf.go)

Change-Id: Ie927ea6a1d69ce49e8d03e56148cb2725e377876
2020-01-31 14:45:52 -05:00
Than McIntosh
fa284af720 [dev.link] cmd/link: convert ELF host object loading to new loader
This is a rewrite of the ELF host object loader to use just the Loader
interfaces for symbol creation, without constructing sym.Symbols. At
the moment this is gated under the temporary linker command line
option "-newldelf".  This version is able to get through all.bash
on linux/amd64.

Change-Id: I99f41368f75b0df9e35ef3c2cf2a702b732540c6
Reviewed-on: https://go-review.googlesource.com/c/go/+/210779
Run-TryBot: Than McIntosh <thanm@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2020-01-09 20:48:48 +00:00
Jeremy Faller
664accc7be [dev.link] cmd/link: remove sym.Symbols from loader
Pushing the wavefront forward requires a single source of truth for
symbols. This CL removes sym.Symbols from the loader for host object
loaders, allowing us to have the single source of truth for symbols be
the loader, not some strange combination of sym.Symbols and the loader.

Change-Id: Ib8ff0117ebe6040fade346047535ff342d781081
Reviewed-on: https://go-review.googlesource.com/c/go/+/209217
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>
2019-12-12 20:57:54 +00:00
Meng Zhuo
ffa5c85c92 cmd/link: fix loadelf failed on MIPS family
The relocation of MIPS64 family ELF is different with other architecure according
to the document from Linux-MIPS

https://www.linux-mips.org/pub/linux/mips/doc/ABI/elf64-2.4.pdf

In "2.9 Relocation" it shows relocation section contains five parts:

1. r_sym Elf64_Word Symbol index
2. r_ssym Elf64_Byte Special symbol
3. r_type3 Elf64_Byte Relocation type
4. r_type2 Elf64_Byte Relocation type
5. r_type Elf64_Byte Relocation type

This CL makes loadelf aware the difference.

Update #35779

Change-Id: Ib221665641972b1c2bfea5a496e3118e5dc0bc45
Reviewed-on: https://go-review.googlesource.com/c/go/+/209317
Run-TryBot: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2019-12-09 18:22:59 +00:00
Cherry Zhang
f7672d39ca [dev.link] all: merge branch 'master' into dev.link
Bring in Than's fix of #35779.

The only merge conflict is cmd/link/internal/loadelf/ldelf.go,
with a modification-deletion conflict.

Change-Id: Id2fcfd2094a31120966a6ea9c462b4ec76646b10
2019-12-03 10:38:43 -05:00
Than McIntosh
f29e53d664 cmd/link: fix bug with -newobj and "ld -r" ELF host objects
When the ELF host object loader encounters a static/hidden symbol, it
creates a sym.Symbol for it but does not enter it into the sym.Symbols
lookup table. Under -newobj mode, this was not happening correctly; we
were adding the sym via loader.LookupOrCreate, which resulted in
collisions when it encountered symbols with the same name + version +
section (this can happen for "ld -r" objects).

Fixes #35779.

Change-Id: I36d40fc1efc03fc1cd8ae6b76cb6a0d2a957389c
Reviewed-on: https://go-review.googlesource.com/c/go/+/208479
Run-TryBot: Than McIntosh <thanm@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2019-11-23 00:06:41 +00:00
Jeremy Faller
aacffb6576 [dev.link] cmd/link: remove old objs from host obj loaders
Change-Id: I9ee853e37090ea015aba817d9aeb2f4cc9ff5a1b
Reviewed-on: https://go-review.googlesource.com/c/go/+/206539
Run-TryBot: Jeremy Faller <jeremy@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2019-11-11 20:19:37 +00:00
Cherry Zhang
48a0b97902 [dev.link] cmd/link: set cgo attributes early when internal cgo linking
In newobj mode, cgo attributes are typically set later, as we
create sym.Symbols later. But when internal cgo linking, the
host object loaders still work with sym.Symbols, and the cgo
attributes need to be set for them to work properly. Therefore,
set them early. This will cause creating some Symbols eagerly,
but they are mostly host object symbols and will need to be
created anyway.

Now all cgo internal linking tests pass on ELF systems.

Change-Id: I023a4df4429acc8ebf5e185f62e6809198497a78
Reviewed-on: https://go-review.googlesource.com/c/go/+/204857
Reviewed-by: Than McIntosh <thanm@google.com>
2019-11-02 00:36:59 +00:00
Jeremy Faller
0e76e2f4e5 [dev.link] cmd/link: elf host obj support w/ new obj files
Add support for elf host objects with new object file format.

Change-Id: Ic5be1953359b9b6b78d9a0b715af69763aefd227
Reviewed-on: https://go-review.googlesource.com/c/go/+/201728
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
2019-10-31 13:11:51 +00:00
Joel Sing
83f205fa88 cmd/link: add support for R_AARCH64_LDST128_ABS_LO12_NC relocations
These are encountered when compiling with -linkmode=internal on openbsd/arm64.

Fixes #31940

Change-Id: I851e6a7da0a3fb3e23b4fa2ed8dce3051c680f11
Reviewed-on: https://go-review.googlesource.com/c/go/+/176697
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2019-05-12 02:55:19 +00:00
Russ Cox
ffd7eba20a cmd/internal/bio: rename Reader.Seek to MustSeek
Renaming the method makes clear, both to readers and to vet,
that this method is not the implementation of io.Seeker:
it cannot fail.

Working toward making the tree vet-safe instead of having
so many exceptions in cmd/vet/all/whitelist.

For #31916.

Change-Id: I3e6ad7264cb0121b4b76935450cccb71d533e96b
Reviewed-on: https://go-review.googlesource.com/c/go/+/176108
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2019-05-09 16:56:31 +00:00
erifan01
d2765de863 cmd/link: support PIE mode with internal link on linux arm64
This CL improves internal link to provide basic support for cgo and PIE:
1, add support for GOT, PLT and GOTPLT.
2, add support for following ELF relocation types which have been used by std
   packages:
     R_AARCH64_ADR_GOT_PAGE
     R_AARCH64_LD64_GOT_LO12_NC
     R_AARCH64_ADR_PREL_PG_HI21
     R_AARCH64_ADD_ABS_LO12_NC
     R_AARCH64_LDST8_ABS_LO12_NC
     R_AARCH64_LDST32_ABS_LO12_NC
     R_AARCH64_LDST64_ABS_LO12_NC
     R_AARCH64_JUMP26
     R_AARCH64_ABS64
     R_AARCH64_PREL32
     R_AARCH64_PREL64

With this change, Go toolchain can be built in internal linking mode, and
pure Go programs can be built with PIE mode in internal linking mode on arm64.

Updates #10373
The prototype of this CL is contributed by Wei Xiao <wei.xiao@arm.com>

Change-Id: I2253923c69e855fd1524d54def309a961dce6247
Reviewed-on: https://go-review.googlesource.com/c/go/+/163579
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
2019-05-02 15:38:36 +00:00
Ian Lance Taylor
3235f7c072 cmd/link: don't fail if multiple ELF sections have the same name
New versions of clang can generate multiple sections named ".text"
when using vague C++ linkage. This is valid ELF, but would cause the
Go linker to report an error when using internal linking:
    symbol PACKAGEPATH(.text) listed multiple times
Avoid the problem by renaming section symbol names if there is a name
collision.

Change-Id: I41127e95003d5b4554aaf849177b3fe000382c02
Reviewed-on: https://go-review.googlesource.com/c/go/+/172697
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2019-04-18 15:07:12 +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
Joel Sing
c90f6dd496 cmd/link: permit duplicate weak symbols
Permit weak symbols to be duplicates - most external linkers allow
this and there are various situations where they can occur (including
retpoline and retguard).

Fixes #29563

Change-Id: I355493c847fbc8f670a85a643db65a4cf8f9883d
Reviewed-on: https://go-review.googlesource.com/c/go/+/169658
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2019-03-29 17:46:01 +00:00
Than McIntosh
2975914a1a cmd/link: move Localentry field in sym.Symbol to cold section
The sym.Symbol 'Localentry' field is used only with cgo and/or
external linking on MachoPPC. Relocate it to sym.AuxSymbol since it is
infrequently used, so as to shrink the main Symbol struct.

Updates #26186

Change-Id: I5872aa3f059270c2a091016d235a1a732695e411
Reviewed-on: https://go-review.googlesource.com/125477
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2018-08-30 12:35:03 +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
Tim Cooper
161874da2a all: update comment URLs from HTTP to HTTPS, where possible
Each URL was manually verified to ensure it did not serve up incorrect
content.

Change-Id: I4dc846227af95a73ee9a3074d0c379ff0fa955df
Reviewed-on: https://go-review.googlesource.com/115798
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
2018-06-01 21:52:00 +00:00
Shawn Smith
d3beea8c52 all: fix misspellings
GitHub-Last-Rev: 468df242d0
GitHub-Pull-Request: golang/go#23935
Change-Id: If751ce3ffa3a4d5e00a3138211383d12cb6b23fc
Reviewed-on: https://go-review.googlesource.com/95577
Run-TryBot: Andrew Bonventre <andybons@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Andrew Bonventre <andybons@golang.org>
2018-02-20 21:02:58 +00:00
Michael Hudson-Doyle
b2d3d6e676 cmd/link/internal/loadelf: fix logic for computing ELF flags on ARM
The linker contains complicated logic for figuring out which float ABI to
indicate it is using on (32 bit) ARM systems: it parses a special section in
host object files to look for a flag indicating use of the hard float ABI. When
loadelf got split into its own package a bug was introduced: if the last host
object file does not contain a float ABI related tag, the ELF header's flag was
set to 0, rather than using the value from the last object file which contained
an ABI tag. Fix the code to only change the value used for the ELF header if a
tag was found.

This fixes an extremely confusing build failure on Ubuntu's armhf builders.

Change-Id: I0845d68d082d1383e4cae84ea85164cdc6bcdddb
Reviewed-on: https://go-review.googlesource.com/92515
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2018-02-07 05:10:13 +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