12804 Commits

Author SHA1 Message Date
David Bozier
6e2804ce6b [LLD] Add support for --unique option
Summary:
Places orphan sections into a unique output section. This prevents the merging of orphan sections of the same name.
Matches behaviour of GNU ld --unique. --unique=pattern is not implemented.

Motivated user case shown in the test has 2 local symbols as they would appear if C++ source has been compiled with -ffunction-sections. The merging of these sections in the case of a partial link (-r) may limit the effectiveness of -gc-sections of a subsequent link.

Reviewers: espindola, jhenderson, bd1976llvm, edd, andrewng, JonChesterfield, MaskRay, grimar, ruiu, psmith

Reviewed By: MaskRay, grimar

Subscribers: emaste, arichardson, MaskRay, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D75536
2020-03-10 12:20:21 +00:00
Fangrui Song
92b5b980d2 [ELF] Postpone evaluation of ORIGIN/LENGTH in a MEMORY command
```
createFiles(args)
 readDefsym
 readerLinkerScript(*mb)
  ...
   readMemory
    readMemoryAssignment("ORIGIN", "org", "o") // eagerly evaluated
target = getTarget();
link(args)
 writeResult<ELFT>()
  ...
   finalizeSections()
    script->processSymbolAssignments()
     addSymbol(cmd) // with this patch, evaluated here
```

readMemoryAssignment eagerly evaluates ORIGIN/LENGTH and returns an uint64_t.
This patch postpones the evaluation to make

* --defsym and symbol assignments
* `CONSTANT(COMMONPAGESIZE)` (requires a non-null `lld:🧝:target`)

work. If the expression somehow requires interaction with memory
regions, the circular dependency may cause the expression to evaluate to
a strange value. See the new test added to memory-err.s

Reviewed By: grimar

Differential Revision: https://reviews.llvm.org/D75763
2020-03-09 08:31:41 -07:00
Fangrui Song
2fed3ca3b5 [lld] Add .clang-tidy to customize readability-identifier-naming.{Member,Parameter,Variable}Case => camelBack
lld/.clang-tidy is almost identical to the top-level .clang-tidy, with the aforementioned customization.

Reviewed By: ruiu

Differential Revision: https://reviews.llvm.org/D75809
2020-03-09 08:26:41 -07:00
Andrew Monshizadeh
3669f0ed4f Refactor TimeProfiler write methods (NFC)
Added a write method for TimeTrace that takes two strings representing
file names. The first is any file name that may have been provided by the
user via `time-trace-file` flag, and the second is a fallback that should
be configured by the caller. This method makes it cleaner to write the
trace output because there is no longer a need to check file names at the
caller and simplifies future TimeTrace usages.

Reviewed By: modocache

Differential Revision: https://reviews.llvm.org/D74514
2020-03-06 14:34:56 -08:00
Fangrui Song
7b8341b257 [ELF][test] Improve MEMORY tests 2020-03-06 14:01:20 -08:00
Benjamin Barenblat
f0f4d41631 [lld][test] Make tests pass when the test directory matches bar
Reviewed By: jhenderson, MaskRay

Differential Revision: https://reviews.llvm.org/D72360
2020-03-06 13:27:02 -08:00
Alexey Lapshin
dcf6494abe LLD already has a mechanism for caching creation of DWARCContext:
llvm::call_once(initDwarfLine, [this]() { initializeDwarf(); });

Though it is not used in all places.

I need that patch for implementing "Remove obsolete debug info" feature
(D74169). But this caching mechanism is useful by itself, and I think it
would be good to use it without connection to "Remove obsolete debug info"
feature. So this patch changes inplace creation of DWARFContext with
its cached version.

Depends on D74308

Reviewed By: ruiu

Differential Revision: https://reviews.llvm.org/D74773
2020-03-06 21:17:07 +03:00
Georgii Rymar
e4ceb8f421 [lib/ObjectYAML] - Make ELFYAML::Relocation::Offset optional.
Currently `yaml2obj` require `Offset` field in a relocation description.
There are many cases when `Offset` is insignificant in a context of a test case.

Making `Offset` optional allows to simplify our test cases.
This is what this patch does.

Also, with this patch `obj2yaml` does not dump a zero offset of a relocation.

Differential revision: https://reviews.llvm.org/D75608
2020-03-06 13:59:58 +03:00
Fangrui Song
71e2ca6e32 [llvm-objdump] -d: print 00000000 <foo>: instead of 00000000 foo:
The new behavior matches GNU objdump. A pair of angle brackets makes tests slightly easier.

`.foo:` is not unique and thus cannot be used in a `CHECK-LABEL:` directive.
Without `-LABEL`, the CHECK line can match the `Disassembly of section`
line and causes the next `CHECK-NEXT:` to fail.

```
Disassembly of section .foo:

0000000000001634 .foo:
```

Bdragon: <> has metalinguistic connotation. it just "feels right"

Reviewed By: rupprecht

Differential Revision: https://reviews.llvm.org/D75713
2020-03-05 18:05:28 -08:00
Fangrui Song
791efb148f [ARM] Rewrite ARMAttributeParser
* Delete boilerplate
* Change functions to return `Error`
* Test parsing errors
* Update callers of ARMAttributeParser::parse() to check the `Error` return value.

Since this patch touches nearly everything in the file, I apply
http://llvm.org/docs/Proposals/VariableNames.html and change variable
names to lower case.

Reviewed By: compnerd

Differential Revision: https://reviews.llvm.org/D75015
2020-03-05 10:57:27 -08:00
Fangrui Song
f9a0056016 [llvm-objdump] --syms: make flags closer to GNU objdump
This fixes several issues. The behavior changes are:

A SHN_COMMON symbol does not have the 'g' flag.
An undefined symbol does not have 'g' or 'l' flag.
A STB_GLOBAL SymbolRef::ST_Unknown symbol has the 'g' flag.
A STB_LOCAL SymbolRef::ST_Unknown symbol has the 'l' flag.

Reviewed By: rupprecht

Differential Revision: https://reviews.llvm.org/D75659
2020-03-05 09:59:53 -08:00
Jordan Rupprecht
c140810ea1 [llvm-readobj] Include section name of notes.
This changes the output of `llvm-readelf -n` from:

```
Displaying notes found at file offset 0x<...> with length 0x<...>:
```

to:

```
Displaying notes found in: .note.foo
```

And similarly, adds a `Name:` field to the `llvm-readobj -n` output for notes.

This change not only increases GNU compatibility, it also makes it much easier to read notes. Note that we still fall back to printing the file offset/length in cases where we don't have a section name, such as when printing notes in program headers or printing notes in a partially stripped file (GNU readelf does the same).

Fixes llvm.org/PR41339.

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D75647
2020-03-05 09:53:14 -08:00
Alexey Lapshin
a130be6ac5 [LLD][NFC] Remove getOffsetInFile() workaround.
Summary:
LLD has workaround for the times when SectionIndex was not passed properly:

LT->getFileLineInfoForAddress(
      S->getOffsetInFile() + Offset, nullptr,
      DILineInfoSpecifier::FileLineInfoKind::AbsoluteFilePath, Info));

S->getOffsetInFile() was added to differentiate offsets between
various sections. Now SectionIndex is properly specified.
Thus it is not necessary to use getOffsetInFile() workaround.
See https://reviews.llvm.org/D58194, https://reviews.llvm.org/D58357.

This patch removes getOffsetInFile() workaround.

Reviewers: ruiu, grimar, MaskRay, espindola

Reviewed By: grimar, MaskRay

Subscribers: emaste, arichardson, llvm-commits

Tags: #llvm, #lld

Differential Revision: https://reviews.llvm.org/D75636
2020-03-05 15:52:46 +03:00
Fangrui Song
9e1319df7e [llvm-readelf] Make --all output order closer to GNU readelf
https://bugs.llvm.org/show_bug.cgi?id=43403

The new order makes it easy to compare the two tools' --all.

Reviewed By: grimar, rupprecht

Differential Revision: https://reviews.llvm.org/D75592
2020-03-04 12:22:12 -08:00
Fangrui Song
c72d60d42f [llvm-objdump] --syms: print st_size as "%016" PRIx64 instead of "%08" PRIx64 for 64-bit objects
This is GNU objdump's behavior and it is reasonable to match.

Reviewed By: grimar

Differential Revision: https://reviews.llvm.org/D75588
2020-03-04 12:09:27 -08:00
Sam Clegg
928e9e1723 [lld][WebAssembly] Add support for --rsp-quoting
This also changes to default style to match the host.

Reviewed By: ruiu

Differential Revision: https://reviews.llvm.org/D75577
2020-03-04 11:41:33 -08:00
Fangrui Song
1044ee827a [ELF][test] Improve llvm-objdump -t tests
In many cases, llvm-nm or llvm-readelf is more suitable.
2020-03-04 10:48:36 -08:00
Stephan Herhut
573c9d666c [lld] Avoid creating files outside of work directory.
Summary:
A test is passing `-o -` to lld in the hope of writing the output to
standard out but that is not the case. Instead it creates a file named
`-.lto.o`. This fixes it by creating a temporary file in the work
directory.

Differential Revision: https://reviews.llvm.org/D75605
2020-03-04 14:46:12 +01:00
evgeny
670a40360e Attempt to fix buildbot after 497c110e 2020-03-04 13:05:02 +03:00
evgeny
497c110e87 [lld][ELF][COFF] Fix archived bitcode files naming
Differential revision: https://reviews.llvm.org/D75422
2020-03-04 12:46:31 +03:00
Hans Wennborg
916be8fd6a Revert abb00753 "build: reduce CMake handling for zlib" (PR44780)
and follow-ups:
a2ca1c2d "build: disable zlib by default on Windows"
2181bf40 "[CMake] Link against ZLIB::ZLIB"
1079c68a "Attempt to fix ZLIB CMake logic on Windows"

This changed the output of llvm-config --system-libs, and more
importantly it broke stand-alone builds. Instead of piling on more fix
attempts, let's revert this to reduce the risk of more breakages.
2020-03-03 11:03:09 +01:00
Nico Weber
ff9bc0c091 fix typo 2020-03-02 21:01:50 -05:00
Fangrui Song
08ff4dc9ad [LTO] onfig::addSaveTemps: clear ResolutionFile upon an error
Otherwise ld.lld -save-temps will crash when writing to ResolutionFile.

llvm-lto2 -save-temps does not crash because it exits immediately.

Reviewed By: evgeny777

Differential Revision: https://reviews.llvm.org/D75426
2020-03-02 17:49:04 -08:00
Pavel Labath
12048a9182 [lld] Fix test failure from d978656fd06
Tweak the test to account for the slightly different wording of the
error message.
2020-03-02 11:28:48 +01:00
Fangrui Song
315f8a55f5 [ELF][PPC32] Don't report "relocation refers to a discarded section" for .got2
Similar to D63182 [ELF][PPC64] Don't report "relocation refers to a discarded section" for .toc

Reviewed By: Bdragon28

Differential Revision: https://reviews.llvm.org/D75419
2020-03-01 19:54:40 -08:00
Fangrui Song
00925aadb3 [ELF][PPC32] Fix canonical PLTs when the order does not match the PLT order
Reviewed By: Bdragon28

Differential Revision: https://reviews.llvm.org/D75394
2020-02-28 22:23:14 -08:00
Fangrui Song
718cbd394a [ELF] Delete two unneeded referenced = true after D65584 2020-02-28 21:59:08 -08:00
Alexey Lapshin
0a2d415bd0 [LLD] Report errors occurred while parsing debug info as warnings.
Summary:
Extracted from D74773. Currently, errors happened while parsing
debug info are reported as errors. DebugInfoDWARF library treats such
errors as "Recoverable errors". This patch makes debug info errors
to be reported as warnings, to support DebugInfoDWARF approach.

Reviewers: ruiu, grimar, MaskRay, jhenderson, espindola

Reviewed By: MaskRay, jhenderson

Subscribers: emaste, aprantl, arichardson, arphaman, llvm-commits

Tags: #llvm, #debug-info, #lld

Differential Revision: https://reviews.llvm.org/D75234
2020-02-29 00:03:18 +03:00
Sam Clegg
a57f1a5435 [lld][WebAssembly] Handle mixed strong and weak undefined symbols
When there are both strong and weak references to an undefined
symbol ensure that the strong reference prevails in the output symbol
generating the correct error.

Test case copied from lld/test/ELF/weak-and-strong-undef.s

Differential Revision: https://reviews.llvm.org/D75322
2020-02-28 10:16:10 -08:00
Peter Smith
1b025665c9 [ELF][LLD][ARM] Add missing REQUIRES: arm to tests
Fix buildbots that don't build ARM backend.
2020-02-28 11:46:01 +00:00
Peter Smith
6b035b607f [LLD][ELF][ARM] Implement Thumb pc-relative relocations for adr and ldr
MC will now output the R_ARM_THM_PC8, R_ARM_THM_PC12 and
R_ARM_THM_PREL_11_0 relocations. These are short-ranged relocations that
are used to implement the adr rd, literal and ldr rd, literal pseudo
instructions.

The instructions use a new RelExpr called R_ARM_PCA in order to calculate
the required S + A - Pa expression, where Pa is AlignDown(P, 4) as the
instructions add their immediate to AlignDown(PC, 4). We also do not want
these relocations to generate or resolve against a PLT entry as the range
of these relocations is so short they would never reach.

The R_ARM_THM_PC8 has a special encoding convention for the relocation
addend, the immediate field is unsigned, yet the addend must be -4 to
account for the Thumb PC bias. The ABI (not the architecture) uses the
convention that the 8-byte immediate of 0xff represents -4.

Differential Revision: https://reviews.llvm.org/D75042
2020-02-28 11:29:29 +00:00
Dan Gohman
197bda587b [WebAssembly] Teach lld how to demangle "__main_argc_argv".
WebAssembly requires that caller and callee signatures match, so it
can't do the usual trick of passing more arguments to main than it
expects. Instead WebAssembly will mangle "main" with argc/argv
parameters as "__main_argc_argv". This patch teaches lld how to
demangle it.

This patch is part of https://reviews.llvm.org/D70700.
2020-02-27 07:55:01 -08:00
Fangrui Song
b305b8a256 [ELF][test] Rename SHF_LINK_ORDER related "metadata" to "linkorder"
Test cleanups.
2020-02-26 17:36:59 -08:00
Fangrui Song
37c7f0d945 [ELF] --orphan-handling=: don't warn/error for input SHT_REL[A] retained by --emit-relocs
They are purposefully skipped by input section descriptions (rL295324).
Similarly, --orphan-handling= should not warn/error for them.
This behavior matches GNU ld.

Reviewed By: grimar

Differential Revision: https://reviews.llvm.org/D75151
2020-02-26 10:32:54 -08:00
Fangrui Song
423194098b [ELF] --orphan-handling=: don't warn/error for unused synthesized sections
This makes --orphan-handling= less noisy.
This change also improves our compatibility with GNU ld.

GNU ld special cases .symtab, .strtab and .shstrtab . We need output section
descriptions for .symtab, .strtab and .shstrtab to suppress:

  <internal>:(.symtab) is being placed in '.symtab'
  <internal>:(.shstrtab) is being placed in '.shstrtab'
  <internal>:(.strtab) is being placed in '.strtab'

With --strip-all, .symtab and .strtab can be omitted (note, --strip-all is not compatible with --emit-relocs).

Reviewed By: nickdesaulniers

Differential Revision: https://reviews.llvm.org/D75149
2020-02-26 08:56:12 -08:00
Reid Kleckner
8a310f40d0 Remove namespace lld { namespace coff { from COFF LLD cpp files
Instead, use `using namespace lld(::coff)`, and fully qualify the names
of free functions where they are defined in cpp files.

This effectively reverts d79c3be618 to follow the new style guide added
in 236fcbc21a7a8872.

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D74882
2020-02-25 17:30:53 -08:00
Fangrui Song
93331a17e8 [ELF] Support archive:file syntax in input section descriptions
Fixes https://bugs.llvm.org/show_bug.cgi?id=44450

https://sourceware.org/binutils/docs/ld/Input-Section-Basics.html#Input-Section-Basics
The following two rules are not implemented.

* `archive:` matches every file in the archive.
* `:file` matches a file not in an archive.

Reviewed By: grimar, ruiu

Differential Revision: https://reviews.llvm.org/D75100
2020-02-25 07:57:43 -08:00
Igor Kudrin
bd2df13ee0 [DebugInfo] Fix printing CIE offsets in EH FDEs.
While the value of the CIE pointer field in a DWARF FDE record is
an offset to the corresponding CIE record from the beginning of
the section, for EH FDE records it is relative to the current offset.
Previously, we did not make that distinction when dumped both kinds
of FDE records and just printed the same value for the CIE pointer
field and the CIE offset; that was acceptable for DWARF FDEs but was
wrong for EH FDEs.

This patch fixes the issue by explicitly printing the offset of the
linked CIE object.

Differential Revision: https://reviews.llvm.org/D74613
2020-02-25 17:10:29 +07:00
Shoaib Meenai
e34ddc09f4 [arcconfig] Delete subproject arcconfigs
From https://secure.phabricator.com/book/phabricator/article/arcanist_new_project/:

> An .arcconfig file is a JSON file which you check into your project's root.

I've done some experimentation, and it looks like the subproject
.arcconfigs just get ignored, as the documentation says. Given that
we're fully on the monorepo now, it's safe to remove them.

Differential Revision: https://reviews.llvm.org/D74996
2020-02-24 16:20:36 -08:00
Rafael Ávila de Espíndola
7b44f0428a Add a llvm::shuffle and use it in lld
With this --shuffle-sections=seed produces the same result in every
host.

Reviewed By: grimar, MaskRay

Differential Revision: https://reviews.llvm.org/D74971
2020-02-22 10:05:29 -08:00
Fangrui Song
73d8d83a6d [ARM] Change ARMAttributeParser::Parse to use support::endianness and simplify 2020-02-21 11:05:33 -08:00
Fangrui Song
dbd7281aa7 [ELF] Shuffle .init_array/.fini_array with --shuffle-sections=
Useful for detecting static initialization order fiasco.

Reviewed By: grimar

Differential Revision: https://reviews.llvm.org/D74887
2020-02-21 08:16:07 -08:00
Fangrui Song
de0dda54d3 [ELF] Warn changed output section address
When the output section address (addrExpr) is specified, GNU ld warns if
sh_addr is different. This patch implements the warning.

Note, LinkerScript::assignAddresses can be called more than once. We
need to record the changed section addresses, and only report the
warnings after the addresses are finalized.

Reviewed By: grimar

Differential Revision: https://reviews.llvm.org/D74741
2020-02-21 08:13:29 -08:00
Fangrui Song
6ed8e20143 [ELF] Ignore the maximum of input section alignments for two cases
Follow-up for D74286.

Notations:

* alignExpr: the computed ALIGN value
* max_input_align: the maximum of input section alignments

This patch changes the following two cases to match GNU ld:

* When ALIGN is present, GNU ld sets output sh_addr to alignExpr, while lld use max(alignExpr, max_input_align)
* When addrExpr is specified but alignExpr is not, GNU ld sets output sh_addr to addrExpr, while lld uses `advance(0, max_input_align)`

Note, sh_addralign is still set to max(alignExpr, max_input_align).

lma-align.test is enhanced a bit to check we don't overalign sh_addr.

fixSectionAlignments() sets addrExpr but not alignExpr for the `!hasSectionsCommand` case.
This patch sets alignExpr as well so that max_input_align will be respected.

Reviewed By: grimar

Differential Revision: https://reviews.llvm.org/D74736
2020-02-21 08:12:00 -08:00
Tamas Petz
14d7b802db [LLD][ELF][ARM] Add test cases for R_ARM_THM_MOV*-type relocs
Summary: This patch adds missing tests cases for R_ARM_THM_MOVW/MOVT* relocations for the sake of completeness.

Reviewers: peter.smith, MaskRay, espindola, psmith

Reviewed By: MaskRay, psmith

Subscribers: psmith, danielkiss, emaste, kristof.beyls, llvm-commits

Tags: #llvm, #lld

Differential Revision: https://reviews.llvm.org/D74827
2020-02-20 10:00:42 +01:00
Fangrui Song
d6d640ebae [ELF][test] Fix section sh_type and sh_flags
A future MC change may add a warning/error when a .section directive
specifies incorrect sh_flags/sh_type.
2020-02-19 22:01:42 -08:00
Sam Clegg
06f1a5c9c2 [lld][WebAssembly] Allow symbols with explict import names to be undefined at link time.
Differential Revision: https://reviews.llvm.org/D74110
2020-02-19 18:02:49 -08:00
Sam Clegg
bd4812776b [WebAssembly] Use llvm::Optional to store optional symbol attributes. NFC.
The changes the in-memory representation of wasm symbols such that their
optional ImportName and ImportModule use llvm::Optional.

ImportName is set whenever WASM_SYMBOL_EXPLICIT_NAME flag is set.
ImportModule (for imports) is currently always set since it defaults to
"env".

In the future we can possibly extent to binary format distingish
import which have explit module names.

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D74109
2020-02-19 17:25:33 -08:00
Fangrui Song
878159038b [ELF][test] Fix --symbol-ordering-file tests of shuffle_sections.s 2020-02-19 17:13:06 -08:00
Fangrui Song
40463301e4 [ELF][test] Fix shuffle_sections.s
C++ standard libraries have different random function implementations.
We cannot expect a particular order.
2020-02-19 17:10:32 -08:00