Commit Graph

12444 Commits

Author SHA1 Message Date
Nico Weber d48ea5da94 lld-link: Add a flag /lldignoreenv that makes lld-link ignore env vars.
This is useful for enforcing that builds are independent of the
environment; it can be used when all system library paths are added
via /libpath: already. It's similar ot cl.exe's /X flag.

Since it should also affect %LINK% (the other caller of
`Process::GetEnv` in lld/COFF), the early-option-parsing needs
to move around a bit. The options are:

- Add a manual loop over the argv ArrayRef and look for "/lldignoreenv".
  This repeats the name of the flag in both Options.td and in
  DriverUtils.cpp.

- Add yet another table.ParseArgs() call just for /lldignoreenv before
  adding %LINK%.

- Use the existing early ParseArgs() that's there for --rsp-quoting and use
  it for /lldignoreenv for %LINK% as well. This means --rsp-quoting
  and /lldignoreenv can't be passed via %LINK%.

I went with the third approach.

Differential Revision: https://reviews.llvm.org/D67456

llvm-svn: 371852
2019-09-13 13:13:52 +00:00
Fangrui Song 51ead00bf8 [ELF] Delete a redundant assignment to SectionBase::assigned. NFC
LinkerScript::discard marks a section dead. It is unnecessary to set the
`assigned` bit.

llvm-svn: 371804
2019-09-13 02:18:04 +00:00
Amy Huang 227d85956b [COFF] Fix to not add archive name to buffer identifiers when they come
from thin archives.

Currently lld adds the archive name to MemoryBufferRef identifiers in order to
ensure they are unique. For thin archives, since the file name is already unique and we
want to keep the original path to the file, don't add the archive name.

Differential Revision: https://reviews.llvm.org/D67295

llvm-svn: 371778
2019-09-12 22:04:56 +00:00
Fangrui Song 2ad25a4aee [ELF] ICF: change a dyn_cast<InputSection> to cast
ICF is performed after EhInputSections and MergeInputSections were
eliminated from inputSections. Every element of inputSections is an
InputSection.

llvm-svn: 371744
2019-09-12 16:46:19 +00:00
Nico Weber d0c8004890 lld-link: Fix tests that do not run on macOS after r371729.
llvm-svn: 371732
2019-09-12 12:35:34 +00:00
Nico Weber 3c44d595be lld-link: Make /linkrepro: take a filename, not a directory.
This makes lld-link behave like ld.lld. I don't see a reason for
the two drivers to have different behavior here.

While here, also make lld-link add a version.txt to the tar, like
ld.lld does.

Differential Revision: https://reviews.llvm.org/D67461

llvm-svn: 371729
2019-09-12 11:44:13 +00:00
Fangrui Song 786ce3fbd6 [ELF] Fix a common-page-size typo
llvm-svn: 371716
2019-09-12 08:59:17 +00:00
Fangrui Song 60ff4dd9cd [ELF] Support -z undefs
-z undefs is the inverse of -z defs. It allows unresolved references
from object files. This can be used to cancel --no-undefined or -z defs.

Reviewed By: ruiu

Differential Revision: https://reviews.llvm.org/D67479

llvm-svn: 371715
2019-09-12 08:55:17 +00:00
Fangrui Song 2aace1ea22 [ELF][test] Make tests more tolerant to exact symbol addresses
llvm-svn: 371588
2019-09-11 06:20:14 +00:00
Amy Huang 7b1d793713 Reland "Change the X86 datalayout to add three address spaces
for 32 bit signed, 32 bit unsigned, and 64 bit pointers."
This reverts 57076d3199.

Original review at https://reviews.llvm.org/D64931.
Review for added fix at https://reviews.llvm.org/D66843.

llvm-svn: 371568
2019-09-10 23:15:38 +00:00
Simon Atanasyan 6c6f5a9984 [mips] Allow PT_LOAD to have overlapping p_offset ranges on EM_MIPS
Port the D64906 <https://reviews.llvm.org/D64906> technique to MIPS.

Fix PR33131

llvm-svn: 371554
2019-09-10 20:19:59 +00:00
Fangrui Song 1eda21e214 [ELF][test] Make tests more tolerant to exact symbol addresses
Delete relocation-local.s and relocation-shared.s - covered by various tests

llvm-svn: 371514
2019-09-10 12:28:07 +00:00
Rui Ueyama 89efb03463 [LLD][COFF] Add index to disambiguate archive members when using -wholearchive
Patch by Markus Böck.

PR42951: When linking an archive with members that have the same name linking
fails when using the -wholearchive option. This patch passes the index
of the member in the archive to the offset parameter to disambiguate the
member.

Differential Revision: https://reviews.llvm.org/D66239

llvm-svn: 371509
2019-09-10 11:50:26 +00:00
Simon Atanasyan 2439b8b0c5 [mips] Make another set of test cases more tolerant to exact symbol addresses. NFC
llvm-svn: 371458
2019-09-09 22:04:20 +00:00
Simon Atanasyan 56e4ea2bff [mips] Fix decoding of microMIPS JALX instruction
microMIPS jump and link exchange instruction stores a target in a
26-bits field. Despite other microMIPS JAL instructions these bits
are target address shifted right 2 bits [1]. The patch fixes the
JALX instruction decoding and uses 2-bit shift.

[1] MIPS Architecture for Programmers Volume II-B: The microMIPS32 Instruction Set

Differential Revision: https://reviews.llvm.org/D67320

llvm-svn: 371428
2019-09-09 17:28:45 +00:00
Fangrui Song e8c0d93360 [ELF] nmagic or omagic: don't allocate PT_PHDR or PF_R PT_LOAD for the !hasPhdrsCommands case
```
part.phdrs = script->hasPhdrsCommands() ? script->createPhdrs() : createPhdrs(part);
```

createPhdrs() allocates a PT_PHDR and a PF_R PT_LOAD, which will be
deleted later in LinkerScript::allocateHeaders, but leave a gap between
the program headers and the first section. Don't allocate the segments
to avoid the gap. PT_INTERP is likely not needed as well.

Reviewed By: ruiu

Differential Revision: https://reviews.llvm.org/D67324

llvm-svn: 371398
2019-09-09 13:08:51 +00:00
Fangrui Song 298c7a09de [ELF][AArch64] Apply some NFC cleanups to AArch64ErrataFix.cpp
Reviewed By: ruiu

Differential Revision: https://reviews.llvm.org/D67310

llvm-svn: 371389
2019-09-09 11:22:27 +00:00
Fangrui Song 88796a7988 [ELF][test] Improve and reorganize another set of tests
Add file-level comments
Replace trivial Input/*.s with echo ... | llvm-mc
Delete insignificant addresses to make them more tolerant to layout changes
Simplify test output

Merge merge-section-types.s into compatible-section-types.s and add a missed case
Merge gnu-ifunc-gotpcrel.s (added in D19517) into gnu-ifunc-dso.s (added in D35119) and add missed cases
Delete typed-undef.s - covered by executable-undefined-ignoreall.s
Delete emit-relocs-shared.s - covered by emit-relocs-merge.s

Replace copy-rel-pie.s and copy-rel-pie2.s with canonical-plt-pcrel.s, canonical-plt-symbolic.s and copy-rel.s:
add -no-pie cases.
add a case that a canonical PLT can be created for STT_GNU_IFUNC. The logic in Symbols.h was untested:

  // ctor of SharedSymbol
  if (this->type == llvm::ELF::STT_GNU_IFUNC)
    this->type = llvm::ELF::STT_FUNC;

llvm-svn: 371361
2019-09-09 03:35:14 +00:00
Simon Atanasyan 9443c18704 [mips] Follow-up to r371313 - fix failed test case. NFC
llvm-svn: 371316
2019-09-07 16:31:37 +00:00
Simon Atanasyan fcef13344d [mips] Make another set of test cases more tolerant to exact symbol addresses. NFC
llvm-svn: 371313
2019-09-07 15:44:40 +00:00
Fangrui Song 0e79890d9b [ELF][test] Improve tests
Add file-level comments
Delete insignificant addresses to make them more tolerant to layout changes
Simplify test output

Delete weak-undef-val.s - covered by relocation-undefined-weak.s
Delete weak-undef-export.s - covered by additional test added to weak-undef.s
Delete version-undef-sym.s - covered by undefined-versioned-symbol.s => version-symbol-undef.s
Delete symbol-ordering-file2.s - covered by symbol-ordering-file.s
Delete gotpcrelx.s - covered by gotpc-relax-und-dso.s => x86-64-gotpc-relax-und-dso.s

llvm-svn: 371299
2019-09-07 10:42:11 +00:00
Fangrui Song 89f7859641 [ELF][test] Improve LTO tests
Add file-level comments
Delete insignificant addresses to make them more tolerant to layout changes
Simplify test output

llvm-svn: 371292
2019-09-07 08:20:09 +00:00
Matthew Voss c177919409 Update lld tests dynamic-list.s and symbol-override.s to use llvm-nm
The following tests failed on Windows bots due to nm not being
available:

  lld/test/ELF/dynamic-list.s
  lld/test/ELF/symbol-override.s

llvm-svn: 371267
2019-09-06 22:51:46 +00:00
Fangrui Song 2682bc3c9d [ELF] Replace error() with errorOrWarn() for the ASSERT command
Summary:
ld.bfd produces an output with --noinhibit-exec when an ASSERT fails.
Use errorOrWarn() so that we can produce an output as well.

An interesting case is that symbol assignments may execute multiple
times, so we probably want to suppress errors for non-final runs.

Reviewed By: peter.smith

Differential Revision: https://reviews.llvm.org/D67285

llvm-svn: 371225
2019-09-06 16:30:22 +00:00
Fangrui Song 8d30c1dcec Reland D66717 [ELF] Do not ICF two sections with different output sections (by SECTIONS commands)
Recommit r370635 (reverted by r371202), with one change: move addOrphanSections() before ICF.

Before, orphan sections in two different partitions may be folded and
moved to the main partition.

Now, InputSection->OutputSection assignment for orphans happens before
ICF. ICF does not fold input sections with different output sections.

With the PR43241 reproduce,
`llvm-objcopy --extract-partition libvr.so libchrome__combined.so libvr.so` => no error

Updated description:

Fixes PR39418. Complements D47241 (the non-linker-script case).

processSectionCommands() assigns input sections to output sections.
ICF is called before it, so .text.foo and .text.bar may be folded even if
their output sections are made different by SECTIONS commands.

```
markLive<ELFT>()
doIcf<ELFT>()                      // During ICF, we don't know the output sections
writeResult()
  combineEhSections<ELFT>()
  script->processSectionCommands() // InputSection -> OutputSection assignment
```

This patch splits processSectionCommands() into processSectionCommands()
and processSymbolAssignments(), and moves
processSectionCommands()/addOrphanSections() before ICF:

```
markLive<ELFT>()
combineEhSections<ELFT>()
script->processSectionCommands()
script->addOrphanSections();
doIcf<ELFT>()                      // should remove folded input sections
writeResult()
  script->processSymbolAssignments()
```

An alternative approach is to unfold a section `sec` in
processSectionCommands() when we find `sec` and `sec->repl` belong to
different output sections. I feel this patch is superior because this
can fold more sections and the decouple of
SectionCommand/SymbolAssignment gives flexibility:

* An ExprValue can't be evaluated before its section is assigned to an
  output section -> we can delete getOutputSectionVA and simplify
  another place where we had to check if the output section is null.
  Moreover, a case in linkerscript/early-assign-symbol.s can be handled
  now.
* processSectionCommands/processSymbolAssignments can be freely moved
  around.

llvm-svn: 371216
2019-09-06 15:57:44 +00:00
Fangrui Song 5d9f419a2e Revert "Revert r370635, it caused PR43241."
This reverts commit 50d2dca22b3b05d0ee4883b0cbf93d7d15f241fc.

llvm-svn: 371215
2019-09-06 15:57:24 +00:00
Fangrui Song 8f10a5f42d [ELF][test] Simplify and reorganize tests
Add file-level comments
Delete insignificant addresses to make them more tolerant to layout changes
Simplify test output
Delete simple Inputs/*.s files

Delete version-script-copy-rel.s - covered by verdef-defaultver.s
Delete version-wildcard.test - covered by version-script-glob.s

llvm-svn: 371213
2019-09-06 15:10:31 +00:00
Nico Weber 8455294f2a Revert r370635, it caused PR43241.
llvm-svn: 371202
2019-09-06 13:23:42 +00:00
Fangrui Song 70e002b50b [ELF][test] Update test after r371185
llvm-svn: 371189
2019-09-06 09:39:48 +00:00
Simon Atanasyan ff2172c9f4 [mips] Make another set of test cases more tolerant to exact symbol addresses. NFC
llvm-svn: 371174
2019-09-06 07:23:02 +00:00
Fangrui Song a2028f73c2 Update SHT_LLVM_PART_EHDR test after r371157
llvm-svn: 371160
2019-09-06 01:18:01 +00:00
Fangrui Song 6dc2bd70bb [ELF] Initialize PhdrEntry::p_align to maxPageSize for PT_LOAD
```
Writer<ELFT>::run
  assignFileOffsets
    setFileOffset
      computeFileOffset
        os->ptLoad->p_align may be smaller than config->maxPageSize
  setPhdrs
    p_align = max(p_align, config->maxPageSize)
```

If we move the config->maxPageSize logic to the constructor of
PhdrEntry, computeFileOffset can be simplified.

Reviewed By: ruiu

Differential Revision: https://reviews.llvm.org/D67211

llvm-svn: 371085
2019-09-05 16:32:31 +00:00
Simon Atanasyan 2172f3f49d [mips] Make a few test cases more tolerant to exact symbol addresses. NFC
llvm-svn: 371065
2019-09-05 13:37:16 +00:00
Rui Ueyama e99dc4ba57 Align output segments correctly
Previously, segments were aligned according to their first section's
alignment requirements. That was not correct, but segments are also
aligned to a page boundary, and a page boundary is usually much larger
than a section alignment requirement, so no one noticed this bug before.

Now, lld has --nmagic option which sets maxPageSize to 1 to effectively
disable page alignment, which reveals the issue.

Fixes https://bugs.llvm.org/show_bug.cgi?id=43212

Differential Revision: https://reviews.llvm.org/D67152

llvm-svn: 371013
2019-09-05 05:30:24 +00:00
Martin Storsjo d581dd5013 [LLD] [COFF] Implement MinGW default manifest handling
In mingw environments, resources are normally compiled to resource
object files directly, instead of letting the linker convert them to
COFF format.

Since some time, GCC supports the notion of a default manifest object.
When invoking the linker, GCC looks for the default manifest object
file, and if found in the expected path, it is added to linker commands.

The default manifest is one that indicates support for the latest known
versions of windows, to implicitly unlock the modern behaviours of certain
APIs.

Not all mingw/gcc distributions include this file, but e.g. in msys2,
the default manifest object is distributed in a separate package (which
can be but might not always be installed).

This means that even if user projects only use one single resource
object file, the linker can end up with two resource object files,
and thus needs to support merging them.

The default manifest has a language id of zero, and GNU ld has got
logic for dropping a manifest with a zero language id, if there's
another manifest present with a nonzero language id. If there are
multiple manifests with a nonzero language id, the merging process
errors out.

Differential Revision: https://reviews.llvm.org/D66825

llvm-svn: 370974
2019-09-04 20:34:00 +00:00
Thomas Lively 09768c5d7a [WebAssembly] Initialize memory in start function
Summary:
 - `__wasm_init_memory` is now the WebAssembly start function instead
   of being called from `__wasm_call_ctors` or called directly by the
   runtime.
 - Adds a new synthetic data symbol `__wasm_init_memory_flag` that is
   atomically incremented from zero to one by the thread responsible
   for initializing memory.
 - All threads now unconditionally perform data.drop on all passive
   segments.
 - Removes --passive-segments and --active-segments flags and controls
   segment type based on --shared-memory instead. The deleted flags
   were only present to ameliorate the upgrade path in Emscripten.

Reviewers: sbc100, aheejin

Subscribers: dschuff, jgravelle-google, sunfish, jfb, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D65783

llvm-svn: 370965
2019-09-04 19:50:39 +00:00
Fangrui Song 7afffb54ea [ELF] Don't shrink RelrSection
Fixes PR43214.

The size of SHT_RELR may oscillate between 2 numbers (see D53003 for a
similar --pack-dyn-relocs=android issue). This can happen if the shrink
of SHT_RELR causes it to take more words to encode relocation offsets
(this can happen with thunks or segments with overlapping p_offset
ranges), and the expansion of SHT_RELR causes it to take fewer words to
encode relocation offsets.

To avoid the issue, add padding 1s to the end of the relocation section
if its size would decrease. Trailing 1s do not decode to more relocations.

Reviewed By: peter.smith

Differential Revision: https://reviews.llvm.org/D67164

llvm-svn: 370923
2019-09-04 16:27:35 +00:00
Fangrui Song 520bdf79b5 [ELF] Fix spell corrector: don't call elf::InputFile::getSymbols() on shared objects
Exposed by pr34872.s

llvm-svn: 370875
2019-09-04 11:02:58 +00:00
Fangrui Song b4745fad24 [ELF] Add a spell corrector for "undefined symbol" diagnostics
Non-undefined symbols with Levenshtein distance 1 or a transposition are
suggestion candidates. This is probably good enough and it can suggest
some missing/superfluous qualifiers: const, restrict, volatile, & and &&
ref-qualifier, e.g.

   error: undefined symbol: foo(int*)
   >>> referenced by b.o:(.text+0x1)
  +>>> did you mean: foo(int const*)
  +>>> defined in: a.o

   error: undefined symbol: foo(int*&)
   >>> referenced by b.o:(.text+0x1)
  +>>> did you mean: foo(int*)
  +>>> defined in: b.o

Reviewed By: ruiu

Differential Revision: https://reviews.llvm.org/D67039

llvm-svn: 370853
2019-09-04 09:04:26 +00:00
Bob Haarman 7dc5e7a0a4 reland "[lld-link] implement -start-lib and -end-lib"
Summary:
This is a re-land of r370487 with a fix for the use-after-free bug
that rev contained.

This implements -start-lib and -end-lib flags for lld-link, analogous
to the similarly named options in ld.lld. Object files after
-start-lib are included in the link only when needed to resolve
undefined symbols. The -end-lib flag goes back to the normal behavior
of always including object files in the link. This mimics the
semantics of static libraries, but without needing to actually create
the archive file.

Reviewers: ruiu, smeenai, MaskRay

Reviewed By: ruiu, MaskRay

Subscribers: akhuang, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66848

llvm-svn: 370816
2019-09-03 20:32:16 +00:00
Ed Maste 5289bbe4d4 ld.lld.1: explain long options may use one or two dashes
Obtained from FreeBSD r329003

llvm-svn: 370800
2019-09-03 17:58:30 +00:00
Ed Maste 174e083345 ld.lld.1: stylistic changes suggested by igor
igor is an automated man page "proofreader" from FreeBSD - see
http://www.wonkity.com/~wblock/igor/igor.pdf

No content change.

llvm-svn: 370799
2019-09-03 17:58:24 +00:00
Martin Storsjo a66fc1c99f [LLD] [COFF] Demangle itanium symbols in mingw mode
Differential Revision: https://reviews.llvm.org/D67051

llvm-svn: 370654
2019-09-02 13:25:46 +00:00
Fangrui Song d8bc6a48ea [ELF] Do not ICF two sections with different output sections (by SECTIONS commands)
Fixes PR39418. Complements D47241 (the non-linker-script case).

processSectionCommands() assigns input sections to output sections.
ICF is called before it, so .text.foo and .text.bar may be folded even if
their output sections are made different by SECTIONS commands.

```
markLive<ELFT>()
doIcf<ELFT>()                      // During ICF, we don't know the output sections
writeResult()
  combineEhSections<ELFT>()
  script->processSectionCommands() // InputSection -> OutputSection assignment
```

This patch splits processSectionCommands() into processSectionCommands() and
processSymbolAssignments(), and moves processSectionCommands() before ICF:

```
markLive<ELFT>()
combineEhSections<ELFT>()
script->processSectionCommands()
doIcf<ELFT>()                      // should remove folded input sections
writeResult()
  script->processSymbolAssignments()
```

An alternative approach is to unfold a section `sec` in
processSectionCommands() when we find `sec` and `sec->repl` belong to
different output sections. I feel this patch is superior because this
can fold more sections and the decouple of
SectionCommand/SymbolAssignment gives flexibility:

* An ExprValue can't be evaluated before its section is assigned to an
  output section -> we can delete getOutputSectionVA and simplify
  another place where we had to check if the output section is null.
  Moreover, a case in linkerscript/early-assign-symbol.s can be handled
  now.
* processSectionCommands/processSymbolAssignments can be freely moved
  around.

Reviewed By: ruiu

Differential Revision: https://reviews.llvm.org/D66717

llvm-svn: 370635
2019-09-02 10:33:58 +00:00
Fangrui Song 4514ac7cfb [ELF] Align SHT_LLVM_PART_EHDR to a maximum page size boundary
Fixes https://bugs.chromium.org/p/chromium/issues/detail?id=998712

SHT_LLVM_PART_EHDR marks the start of a partition. The partition
sections will be extracted to a separate file. Align to the next maximum
page size boundary so that we can find the ELF header at the start. We
cannot benefit from overlapping p_offset ranges with the previous
segment anyway.

It seems we lack some llvm-objcopy --extract-main-partition and
--extract-partition sanity checks. It may place EHDR at the start
even if p_offset if non zero. Anyway, the lld change is justified for
the reasons above.

Reviewed By: ruiu

Differential Revision: https://reviews.llvm.org/D67032

llvm-svn: 370629
2019-09-02 08:49:50 +00:00
Vlad Tsyrklevich 802aab5de8 Revert "[lld-link] implement -start-lib and -end-lib"
This reverts commit r370487 as it is causing ASan/MSan failures on
sanitizer-x86_64-linux-fast

llvm-svn: 370550
2019-08-30 23:24:41 +00:00
Sam Clegg fecfc5920a [lld][WebAssembly] Fix spurious signature mismatch warnings
Summary:
This a follow up on: https://reviews.llvm.org/D62153

Handle the case where there are multiple object files that contain
undefined references to the same function.  We only generate a function
variant if the existing symbol is directly called.

See: https://github.com/emscripten-core/emscripten/issues/8995

Subscribers: dschuff, jgravelle-google, aheejin, sunfish, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67015

llvm-svn: 370509
2019-08-30 19:50:59 +00:00
Martin Storsjo 8c189e50c7 [LLD] [COFF] Add a missing REQUIRES line to a recently added test. NFC.
This should fix failing buildbots like
http://lab.llvm.org:8011/builders/clang-cmake-aarch64-lld/builds/7180.

llvm-svn: 370491
2019-08-30 17:26:54 +00:00
Bob Haarman fd7569c8e3 [lld-link] implement -start-lib and -end-lib
Summary:
This implements -start-lib and -end-lib flags for lld-link, analogous
to the similarly named options in ld.lld. Object files after
-start-lib are included in the link only when needed to resolve
undefined symbols. The -end-lib flag goes back to the normal behavior
of always including object files in the link. This mimics the
semantics of static libraries, but without needing to actually create
the archive file.

Reviewers: ruiu, smeenai, MaskRay

Reviewed By: ruiu, MaskRay

Subscribers: akhuang, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66848

llvm-svn: 370487
2019-08-30 16:50:10 +00:00
Fangrui Song 688183ec54 [ELF] Set `referenced` bit of Undefined created by BitcodeFile
D64136 and D65584, while fixing STB_WEAK issues and improving our
compatibility with ld.bfd, can cause another STB_WEAK problem related to
LTO:

If %tundef.o has an undefined reference on f,
and %tweakundef.o has a weak undefined reference on f,
%tdef.o has a definition of f

```
ld.lld %tundef.o %tweakundef.o --start-lib %tdef.o --end-lib
```

1) `%tundef.o` doesn't set the `referenced` bit.
2) `%weakundef.o` changes the binding from STB_GLOBAL to STB_WEAK
3) `%tdef.o` is not fetched because the binding is weak.

Step (1) is incorrect. This patch sets the `referenced` bit of Undefined
created by bitcode files.

Reviewed By: ruiu

Differential Revision: https://reviews.llvm.org/D66992

llvm-svn: 370437
2019-08-30 07:10:30 +00:00