Commit Graph

527 Commits

Author SHA1 Message Date
Peter Collingbourne f17b149d8c MC: Change object writers to use endian::Writer. NFCI.
Part of PR37466.

Differential Revision: https://reviews.llvm.org/D47040

llvm-svn: 332861
2018-05-21 18:17:42 +00:00
Peter Collingbourne 147db3e628 MC: Change MCAssembler::writeSectionData and writeFragmentPadding to take a raw_ostream. NFCI.
Also clean up a couple of hacks where we were writing the section
contents to another stream by setting the object writer's stream,
writing and setting it back.

Part of PR37466.

Differential Revision: https://reviews.llvm.org/D47038

llvm-svn: 332858
2018-05-21 18:11:35 +00:00
Peter Collingbourne e3f652973e Support: Simplify endian stream interface. NFCI.
Provide some free functions to reduce verbosity of endian-writing
a single value, and replace the endianness template parameter with
a field.

Part of PR37466.

Differential Revision: https://reviews.llvm.org/D47032

llvm-svn: 332757
2018-05-18 19:46:24 +00:00
Peter Collingbourne 8e173e1189 MC: Remove dead code. NFCI.
We should never emit an SHT_DYNSYM into an object file.

llvm-svn: 331821
2018-05-08 22:59:05 +00:00
Sam Clegg 22c568ba73 [MC] ELFObjectWriter: Removing unneeded variable and cast
Differential Revision: https://reviews.llvm.org/D46289

llvm-svn: 331704
2018-05-07 23:52:17 +00:00
Vlad Tsyrklevich 201a1086cf ELFObjectWriter: Allow one unique symver per symbol
Summary:
Only allow a single unique .symver alias per symbol. This matches the
behavior of gas. I noticed that we ignored multiple mismatched symver
directives looking at https://reviews.llvm.org/D45798

Reviewers: pcc, tejohnson, espindola

Reviewed By: pcc

Subscribers: emaste, arichardson, llvm-commits, kcc

Differential Revision: https://reviews.llvm.org/D45845

llvm-svn: 331078
2018-04-27 20:32:34 +00:00
Rafael Espindola 47b4d6ba19 Delay creating an alias for @@@.
With this we only create an alias for @@@ once we know if it should
use @ or @@. This avoids last minutes renames and hacks to handle MS
names.

This only handles the ELF writer. LTO still has issues with @@@
aliases.

llvm-svn: 327160
2018-03-09 18:42:25 +00:00
Lang Hames 60fbc7cc38 [MC] Thread unique_ptr<MCObjectWriter> through the create.*ObjectWriter
functions.

This makes the ownership of the resulting MCObjectWriter clear, and allows us
to remove one instance of MCObjectStreamer's bizarre "holding ownership via
someone else's reference" trick.

llvm-svn: 315327
2017-10-10 16:28:07 +00:00
Lang Hames dcb312bdb9 [MC] Plumb unique_ptr<MCELFObjectTargetWriter> through createELFObjectWriter to
ELFObjectWriter's constructor.

Fixes the same ownership issue for ELF that r315245 did for MachO:
ELFObjectWriter takes ownership of its MCELFObjectTargetWriter, so we want to
pass this through to the constructor via a unique_ptr, rather than a raw ptr.

llvm-svn: 315254
2017-10-09 23:53:15 +00:00
Simon Atanasyan ede43b71f8 [mips] Implement generation of relocations "chains" used by N32 ABI
In case of using a "nested" relocation expressions like this
`%hi(%neg(%gp_rel()))`, N32 ABI requires generation of three consecutive
relocations. That differs from the N64 ABI case where all relocations
are packed into the single relocation record.

llvm-svn: 313879
2017-09-21 14:04:53 +00:00
Simon Atanasyan 9f676a7798 [mips] Do not pass redundant IsN64 flag to MCELFObjectTargetWriter. NFC
Now we pass the 'Is64_' flag to the MCELFObjectTargetWriter ctor iif
when we make deal with N64 ABI. So it is redundant to pass additional
'IsN64' flag.

llvm-svn: 313878
2017-09-21 14:04:47 +00:00
Rafael Espindola ceecfe5be2 Simplify interface now that we don't need to pass IsPCRel. NFC.
llvm-svn: 307734
2017-07-11 23:56:10 +00:00
Rafael Espindola 8a261c2565 Add a common error checking for some invalid expressions.
This refactors a bit of duplicated code and fixes an assertion failure
on ELF.

llvm-svn: 306035
2017-06-22 17:25:35 +00:00
Saleem Abdulrasool 1f62f57b37 sink DebugCompressionType into MC for exposing to clang
This is a preparatory change to expose the debug compression style to
clang.  It requires exposing the enumeration and passing the actual
value through to the backend from the frontend in actual value form
rather than a boolean that selects the GNU style of debug info
compression.

Minor tweak to the ELF Object Writer to use a variable for re-used
values.  Add an assertion that debug information format is one of the
two currently known types if debug information is being compressed.

llvm-svn: 305038
2017-06-09 00:40:19 +00:00
Zachary Turner 264b5d9e88 Move Object format code to lib/BinaryFormat.
This creates a new library called BinaryFormat that has all of
the headers from llvm/Support containing structure and layout
definitions for various types of binary formats like dwarf, coff,
elf, etc as well as the code for identifying a file from its
magic.

Differential Revision: https://reviews.llvm.org/D33843

llvm-svn: 304864
2017-06-07 03:48:56 +00:00
Chandler Carruth 6bda14b313 Sort the remaining #include lines in include/... and lib/....
I did this a long time ago with a janky python script, but now
clang-format has built-in support for this. I fed clang-format every
line with a #include and let it re-sort things according to the precise
LLVM rules for include ordering baked into clang-format these days.

I've reverted a number of files where the results of sorting includes
isn't healthy. Either places where we have legacy code relying on
particular include ordering (where possible, I'll fix these separately)
or where we have particular formatting around #include lines that
I didn't want to disturb in this patch.

This patch is *entirely* mechanical. If you get merge conflicts or
anything, just ignore the changes in this patch and run clang-format
over your #include lines in the files.

Sorry for any noise here, but it is important to keep these things
stable. I was seeing an increasing number of patches with irrelevant
re-ordering of #include lines because clang-format was used. This patch
at least isolates that churn, makes it easy to skip when resolving
conflicts, and gets us to a clean baseline (again).

llvm-svn: 304787
2017-06-06 11:49:48 +00:00
Eugene Zelenko 7975b99fe6 [MC] Fix some Clang-tidy modernize-use-using warnings; other minor fixes (NFC).
llvm-svn: 301485
2017-04-26 22:31:39 +00:00
Peter Collingbourne 36003057ac MC: Remove unused virtual function MCObjectWriter::isWeak. NFC.
llvm-svn: 299817
2017-04-08 23:35:49 +00:00
Evgeniy Stepanov 43dcf4d330 Fix asm printing of associated sections.
Make MCSectionELF::AssociatedSection be a link to a symbol, because
that's how it works in the assembly, and use it in the asm printer.

llvm-svn: 297769
2017-03-14 19:28:51 +00:00
Vassil Vassilev 89e36cc04c Silence a warning "hiding virtual function".
llvm-svn: 297018
2017-03-06 15:50:59 +00:00
Peter Collingbourne 5b75fd9e56 MC: De-duplicate the object streamer implementations of EmitFileDirective into MCObjectStreamer. NFCI.
llvm-svn: 296912
2017-03-03 21:22:06 +00:00
Eugene Zelenko d3a6c897ba [MC] Fix some Clang-tidy modernize and Include What You Use warnings; other minor fixes (NFC).
llvm-svn: 294813
2017-02-11 00:27:28 +00:00
Rafael Espindola dc1c3011fd Make it possible to set SHF_LINK_ORDER explicitly.
This will make it possible to add support for gcing user metadata
(asan for example).

llvm-svn: 294589
2017-02-09 14:59:20 +00:00
Rafael Espindola 13a79bbfe5 Change how we handle section symbols on ELF.
On ELF every section can have a corresponding section symbol. When in
an assembly file we have

.quad .text

the '.text' refers to that symbol.

The way we used to handle them is to leave .text an undefined symbol
until the very end when the object writer would map them to the
actual section symbol.

The problem with that is that anything before the end would see an
undefined symbol. This could result in bad diagnostics
(test/MC/AArch64/label-arithmetic-diags-elf.s), or incorrect results
when using the asm streamer (est/MC/Mips/expansion-jal-sym-pic.s).

Fixing this will also allow using the section symbol earlier for
setting sh_link of SHF_METADATA sections.

This patch includes a few hacks to avoid changing our behaviour when
handling conflicts between section symbols and other symbols. I
reported pr31850 to track that.

llvm-svn: 293936
2017-02-02 21:26:06 +00:00
George Rimar 167ca4ae7e Recommit r292214 "[Support/Compression] - Change zlib API to return Error instead of custom status"
No any changes, will follow up with D28807 commit containing APLi change for clang
to fix build issues happened.

Original commit message:
[Support/Compression] - Change zlib API to return Error instead of custom status.

Previously API returned custom enum values.
Patch changes it to return Error with string description.
That should help users to report errors in universal way.

Differential revision: https://reviews.llvm.org/D28684

llvm-svn: 292226
2017-01-17 15:45:07 +00:00
George Rimar 715540f207 Revert r292214 "[Support/Compression] - Change zlib API to return Error instead of custom status."
It broked clang:
http://lab.llvm.org:8080/green//job/clang-stage1-cmake-RA-incremental_build/34218/consoleFull#46141505449ba4694-19c4-4d7e-bec5-911270d8a58c

llvm-svn: 292217
2017-01-17 13:27:58 +00:00
George Rimar e29a32e9ce [Support/Compression] - Change zlib API to return Error instead of custom status.
Previously API returned custom enum values.
Patch changes it to return Error with string description.
That should help users to report errors in universal way.

Differential revision: https://reviews.llvm.org/D28684

llvm-svn: 292214
2017-01-17 13:20:17 +00:00
Saleem Abdulrasool 9b106ea072 MC: ensure that we have a section before accessing it
We would attempt to access the symbol section without ensuring that the symbol
was not absolute.  When the assembler referenced relocation is not evaluated to
the absolute, but when we record the relocation, we would query the section.
Because the symbol is absolute, it does not have a section associated with it,
triggering an assertion.  Just be more careful about the access of the section.

Addresses PR31064!

llvm-svn: 287619
2016-11-22 04:32:54 +00:00
Rafael Espindola 39751afc4e Misc improvements to StringTableBuilder.
This patch adds write methods to StringTableBuilder so that it is
easier to change the underlying implementation.

Using the write methods, avoid creating a temporary buffer when using
mmaped output.

It also uses a more compact key in the DenseMap. Overall this produces
a slightly faster lld:

firefox
  master 6.853419709
  patch  6.841968912 1.00167361138x faster
chromium
  master 4.297280174
  patch  4.298712163 1.00033323147x slower
chromium fast
  master 1.802335952
  patch  1.806872459 1.00251701521x slower
the gold plugin
  master 0.3247149
  patch  0.321971644 1.00852017888x faster
clang
  master 0.551279945
  patch  0.543733194 1.01387951128x faster
llvm-as
  master 0.032743458
  patch  0.032143478 1.01866568391x faster
the gold plugin fsds
  master 0.350814247
  patch  0.348571741 1.00643341309x faster
clang fsds
  master 0.6281672
  patch  0.621130222 1.01132931187x faster
llvm-as fsds
  master 0.030168899
  patch  0.029797155 1.01247582194x faster
scylla
  master 3.104222518
  patch  3.059590248 1.01458766252x faster

llvm-svn: 283266
2016-10-04 22:43:25 +00:00
Rafael Espindola 48975881ab Delete some dead code.
Found by gcc 6.

llvm-svn: 273303
2016-06-21 19:48:12 +00:00
George Rimar c91e38c5eb Recommit 270977 - [llvm-mc] - Teach llvm-mc to generate zlib styled compression sections.
Fix: updated clang code which was not updated by mistake.

Original commit message:
[llvm-mc] - Teach llvm-mc to generate zlib styled compression sections.

This patch is strongly based on previously reverted D20331.
(because of gnuutils < 2.26 does not support compressed debug sections in non zlib-gnu style)

Difference that this patch supports both zlib and zlib-gnu styles.

-compress-debug-sections option now supports next values:

-compress-debug-sections=zlib-gnu
-compress-debug-sections=zlib
-compress-debug-sections=none
Previously specifying -compress-debug-sections enabled zlib-gnu compression,
so anyone can put "-compress-debug-sections=zlib-gnu" to restore the behavior
that was before this patch for case when compression was enabled.

Differential revision: http://reviews.llvm.org/D20676

llvm-svn: 270987
2016-05-27 12:27:32 +00:00
George Rimar e79fc3efca Revert r270977 ([llvm-mc] - Teach llvm-mc to generate zlib styled compression sections.)
It broke buildbot:
http://lab.llvm.org:8011/builders/llvm-clang-lld-x86_64-scei-ps4-ubuntu-fast/builds/13585/steps/build/logs/stdio

Initial commit message:
[llvm-mc] - Teach llvm-mc to generate zlib styled compression sections.

This patch is strongly based on previously reverted D20331.
(because of gnuutils < 2.26 does not support compressed debug sections in non zlib-gnu style)

Difference that this patch supports both zlib and zlib-gnu styles.

-compress-debug-sections option now supports next values:

-compress-debug-sections=zlib-gnu
-compress-debug-sections=zlib
-compress-debug-sections=none
Previously specifying -compress-debug-sections enabled zlib-gnu compression,
so anyone can put "-compress-debug-sections=zlib-gnu" to restore the behavior
that was before this patch for case when compression was enabled.

Differential revision: http://reviews.llvm.org/D20676

llvm-svn: 270978
2016-05-27 10:06:16 +00:00
George Rimar 48dcd2b806 [llvm-mc] - Teach llvm-mc to generate zlib styled compression sections.
This patch is strongly based on previously reverted D20331.
(because of gnuutils < 2.26 does not support compressed debug sections in non zlib-gnu style)

Difference that this patch supports both zlib and zlib-gnu styles.

-compress-debug-sections option now supports next values:

-compress-debug-sections=zlib-gnu
-compress-debug-sections=zlib
-compress-debug-sections=none
Previously specifying -compress-debug-sections enabled zlib-gnu compression,
so anyone can put "-compress-debug-sections=zlib-gnu" to restore the behavior
that was before this patch for case when compression was enabled.

Differential revision: http://reviews.llvm.org/D20676

llvm-svn: 270977
2016-05-27 09:58:08 +00:00
Richard Smith b910e56604 Revert r270569 (teach llvm-mc to generate compressed debug sections in zlib
style). It appears that current ELF linkers are not ready for this.

llvm-svn: 270638
2016-05-25 00:14:12 +00:00
George Rimar 68003e0fbf Recommit r270070 ([llvm-mc] - Teach llvm-mc to generate compressed debug sections in zlib style.)
Now, after landing r270560, r270557, r270320 it is a proper time.

Original commit message:
[llvm-mc] - Teach llvm-mc to generate compressed debug sections in zlib style.

Before this patch llvm-mc generated zlib-gnu styled sections. 
That means no SHF_COMPRESSED flag was set, magic 'zlib' signature
was used in combination with full size field. Sections were renamed to "*.z*".
This patch reimplements the compression style to zlib one as zlib-gnu looks
to be depricated everywhere.

Differential revision: http://reviews.llvm.org/D20331

llvm-svn: 270569
2016-05-24 15:19:35 +00:00
George Rimar cf2bf9d015 Temporarily revert r270070
It broke buildbot:
http://lab.llvm.org:8011/builders/clang-s390x-linux/builds/4817/steps/ninja%20check%201/logs/stdio

Actually it is just because D20273 not yet commited, but these 2 were crossing with each other,
and I`ll better find the way to land them separatelly soon.

Initial commit message:

[llvm-mc] - Teach llvm-mc to generate compressed debug sections in zlib style.

Before this patch llvm-mc generated zlib-gnu styled sections. 
That means no SHF_COMPRESSED flag was set, magic 'zlib' signature
was used in combination with full size field. Sections were renamed to "*.z*".
This patch reimplements the compression style to zlib one as zlib-gnu looks
to be depricated everywhere.

Differential revision: http://reviews.llvm.org/D20331

llvm-svn: 270075
2016-05-19 15:58:05 +00:00
George Rimar 99c901fc47 [llvm-mc] - Teach llvm-mc to generate compressed debug sections in zlib style.
Before this patch llvm-mc generated zlib-gnu styled sections. 
That means no SHF_COMPRESSED flag was set, magic 'zlib' signature
was used in combination with full size field. Sections were renamed to "*.z*".
This patch reimplements the compression style to zlib one as zlib-gnu looks
to be depricated everywhere.

Differential revision: http://reviews.llvm.org/D20331

llvm-svn: 270070
2016-05-19 15:08:31 +00:00
Daniel Sanders a463d31a64 [mips] Correct the ordering of HI/LO pairs in the relocation table.
Summary:
There seems to have been a misunderstanding as to the meaning of 'offset' in
the rules laid down by our ABI. The previous code believed that 'offset' meant
the offset within the section that the relocation is applied to. However, it
should have meant the offset from the symbol used in the relocation expression.

This patch adds two fields to ELFRelocationEntry and uses them to correct the
order of relocations for MIPS. These fields contain:
* The original symbol before shouldRelocateWithSymbol() is considered. This
  ensures that R_MIPS_GOT16 is able to correctly distinguish between local and
  external symbols, allowing us to tell whether %got() requires a matching
  %lo() or not (local symbols require one, external symbols don't). It also
  prevents confusing cases where the fuzzy matching rules cause things like
  %hi(foo)/%lo(foo+3) and %hi(bar)/%lo(bar+1) to swap their %lo()'s.
* The original offset before shouldRelocateWithSymbol() is considered. The
  existing Addend field is always zero when the object uses in place addends
  (because it's already moved it to the encoding) but MIPS needs to use the
  original offset to ensure that the linker correctly calculates the carry-in
  bit for %hi() and %got().

IAS ensures that unmatchable %hi()/%got() relocations are placed at the end of
the table to ensure that the linker rejects the table (we're unable to report
such errors directly). The alternatives to this risk accidental matching
against inappropriate relocations which may silently compute incorrect values
due to an incorrect carry bit between the %lo() and %hi()/%got().

Reviewers: sdardis

Subscribers: dsanders, sdardis, rafael, llvm-commits

Differential Revision: http://reviews.llvm.org/D19718

llvm-svn: 268733
2016-05-06 13:49:25 +00:00
Daniel Sanders fe98b2f54b [mips] Use MipsMCExpr instead of MCSymbolRefExpr for all relocations.
Summary:
This is much closer to the way MIPS relocation expressions work
(%hi(foo + 2) rather than %hi(foo) + 2) and removes the need for the
various bodges in MipsAsmParser::evaluateRelocExpr().

Removing those bodges ensures that the constant stored in MCValue is the
full 32 or 64-bit (depending on ABI) offset from the symbol. This will be used
to correct the %hi/%lo matching needed to sort the relocation table correctly.

As part of this:
* Gave MCExpr::print() the ability to omit parenthesis when emitting a
  symbol reference inside a MipsMCExpr operator like %hi(X). Without this
  we print things like %lo(($L1)).
* %hi(%neg(%gprel(X))) is now three MipsMCExpr's instead of one. Most of
  the related special cases have been removed or moved to MipsMCExpr. We
  can remove the rest as we gain support for the less common relocations
  when they are not part of this specific combination.
* Renamed MipsMCExpr::VariantKind and the enum prefix ('VK_') to avoid confusion
  with MCSymbolRefExpr::VariantKind and its prefix (also 'VK_').
* fixup_Mips_GOT_Local and fixup_Mips_GOT_Global were found to be identical
  and merged into fixup_Mips_GOT.
* MO_GOT16 and MO_GOT turned out to be identical and have been merged into
  MO_GOT.
* VK_Mips_GOT and VK_Mips_GOT16 turned out to be the same thing so they
  have been merged into MEK_GOT

Reviewers: sdardis

Subscribers: dsanders, sdardis, llvm-commits

Differential Revision: http://reviews.llvm.org/D19716

llvm-svn: 268379
2016-05-03 13:35:44 +00:00
David Blaikie a0fa262181 [MC/ELFObjectWriter] Fix indentation of class body.
llvm-svn: 266136
2016-04-12 21:45:53 +00:00
Evgeniy Stepanov a023f79db1 Handle section vs global name conflict.
This is a fix for PR26941.

When there is both a section and a global definition with the same
name, the global wins.

Section symbols are not added to the symbol table; section references
are left undefined and fixed up in the object writer unless they've
been satisfied by some other definition.

llvm-svn: 264649
2016-03-28 20:36:28 +00:00
Eugene Zelenko ecefe5a81f Fix Clang-tidy readability-redundant-control-flow warnings; other minor fixes.
Differential revision: http://reviews.llvm.org/D16793

llvm-svn: 259539
2016-02-02 18:20:45 +00:00
Rafael Espindola b718237dfc Accept subtractions involving a weak symbol.
When a symbol S shows up in an expression in assembly there are two
possible interpretations
* The expression is referring to the value of S in this file.
* The expression is referring to the value after symbol resolution.

In the first case the assembler can reason about the value and try to
produce a relocation.
In the second case, that is only possible if the symbol cannot be
preempted.

Assemblers are not very consistent about which interpretation gets used.
This changes MC to agree with GAS in the case of an expression of the
form "Sym - WeakSym".

llvm-svn: 258329
2016-01-20 18:57:48 +00:00
Rafael Espindola 5568c83a60 Handle 64 bit offsets.
No tests since llvm-mc takes 14 seconds on it. I will try to improve it
and then test.

Part of pr26208.

llvm-svn: 258129
2016-01-19 15:19:08 +00:00
Rafael Espindola 8340f94df1 Convert a few assert failures into proper errors.
Fixes PR25944.

llvm-svn: 257697
2016-01-13 22:56:57 +00:00
Rafael Espindola 00ebfd4b43 Simplify. NFC.
llvm-svn: 257689
2016-01-13 22:23:36 +00:00
Rafael Espindola f44db24e1f Avoid explicit relocation sorting most of the time.
These days relocations are created and stored in a deterministic way.
The order they are created is also suitable for the .o file, so we don't
need an explicit sort.

The last remaining exception is MIPS.

llvm-svn: 255902
2015-12-17 16:22:06 +00:00
Rafael Espindola d0e16522c7 Always sort by offset first. NFC.
Every target changing sortRelocs was first calling the parent
implementation. Just run that first.

llvm-svn: 255898
2015-12-17 15:08:24 +00:00
Oliver Stannard 9be59af3ab [Assembler] Make fatal assembler errors non-fatal
Currently, if the assembler encounters an error after parsing (such as an
out-of-range fixup), it reports this as a fatal error, and so stops after the
first error. However, for most of these there is an obvious way to recover
after emitting the error, such as emitting the fixup with a value of zero. This
means that we can report on all of the errors in a file, not just the first
one. MCContext::reportError records the fact that an error was encountered, so
we won't actually emit an object file with the incorrect contents.

Differential Revision: http://reviews.llvm.org/D14717

llvm-svn: 253328
2015-11-17 10:00:43 +00:00
Rafael Espindola 21956e4007 Add a RAW mode to StringTableBuilder.
In this mode it just tries to tail merge the strings without imposing any other
format constrains. It will not, for example, add a null byte between them.

Also add support for keeping a tentative size and offset if we decide to
not optimize after all.

This will be used shortly in lld for merging SHF_STRINGS sections.

llvm-svn: 251153
2015-10-23 21:48:05 +00:00