Commit Graph

481 Commits

Author SHA1 Message Date
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
Rafael Espindola fc063e8fec Avoid storing a second copy of each string in StringTableBuilder.
This was only use in the extremely uncommon case of @@@ symbols on ELF.

llvm-svn: 251039
2015-10-22 18:32:06 +00:00
Rafael Espindola e3a20f57d9 Fix pr24486.
This extends the work done in r233995 so that now getFragment (in addition to
getSection) also works for variable symbols.

With that the existing logic to decide if a-b can be computed works even if
a or b are variables. Given that, the expression evaluation can avoid expanding
variables as aggressively and that in turn lets the relocation code see the
original variable.

In order for this to work with the asm streamer, there is now a dummy fragment
per section. It is used to assign a section to a symbol when no other fragment
exists.

This patch is a joint work by Maxim Ostapenko andy myself.

llvm-svn: 249303
2015-10-05 12:07:05 +00:00
David Majnemer abdb2d2aba [MC] Allow MCObjectWriter's output stream to be swapped out
There are occasions where it is useful to consider the entirety of the
contents of a section.  For example, compressed debug info needs the
entire section available before it can compress it and write it out.
The compressed debug info scenario was previously implemented by
mirroring the implementation of writeSectionData in the ELFObjectWriter.

Instead, allow the output stream to be swapped on demand.  This lets
callers redirect the output stream to a more convenient location before
it hits the object file.

No functionality change is intended.

Differential Revision: http://reviews.llvm.org/D12509

llvm-svn: 246554
2015-09-01 16:19:03 +00:00
Rafael Espindola 2cd195166f Convert a member variable to a local one.
llvm-svn: 241284
2015-07-02 16:59:57 +00:00
Rafael Espindola 6dff814cdf Diagnose undefined temporary symbols.
We already disallowed

.global .Lfoo

so this is reasonable.

This is a small cherry pick from r240130.

llvm-svn: 240681
2015-06-25 20:10:45 +00:00
Daniel Jasper 41de8027b1 Revert r240302 ("Bring r240130 back.").
This causes errors like:

  ld: error: blah.o: requires dynamic R_X86_64_PC32 reloc against '' which
  may overflow at runtime; recompile with -fPIC
  blah.cc:function f(): error: undefined reference to ''
  blah.o:g(): error: undefined reference to ''

I have not yet come up with an appropriate reproduction.

llvm-svn: 240394
2015-06-23 11:31:32 +00:00
Alexander Kornienko f00654e31b Revert r240137 (Fixed/added namespace ending comments using clang-tidy. NFC)
Apparently, the style needs to be agreed upon first.

llvm-svn: 240390
2015-06-23 09:49:53 +00:00
Evgeniy Stepanov 9e0d41ab09 Fix PR23914.
r226830 moved the declaration of Buf to a nested scope, resulting
in a dangling reference (in StringRef Name), and a use-after-free.

llvm-svn: 240357
2015-06-22 23:36:03 +00:00
Rafael Espindola 2d6bae2e09 Bring r240130 back.
Now that pr23900 is fixed, we can bring it back with no changes.

Original message:

Make all temporary symbols unnamed.

What this does is make all symbols that would otherwise start with a .L
(or L on MachO) unnamed.

Some of these symbols still show up in the symbol table, but we can just
make them unnamed.

In order to make sure we produce identical results when going thought assembly,
all .L (not just the compiler produced ones), are now unnamed.

Running llc on llvm-as.opt.bc, the peak memory usage goes from 208.24MB to
205.57MB.

llvm-svn: 240302
2015-06-22 17:52:52 +00:00
Yaron Keren a81d59e97f Update ELFObjectWriter::reset() following r238073.
llvm-svn: 240218
2015-06-20 11:54:32 +00:00
Nico Weber 67e715ff7d Revert 240130, it caused crashes (repro in PR23900).
llvm-svn: 240193
2015-06-19 23:43:47 +00:00
Alexander Kornienko 70bc5f1398 Fixed/added namespace ending comments using clang-tidy. NFC
The patch is generated using this command:

tools/clang/tools/extra/clang-tidy/tool/run-clang-tidy.py -fix \
  -checks=-*,llvm-namespace-comment -header-filter='llvm/.*|clang/.*' \
  llvm/lib/


Thanks to Eugene Kosov for the original patch!

llvm-svn: 240137
2015-06-19 15:57:42 +00:00
Rafael Espindola 284a750c5f Make all temporary symbols unnamed.
What this does is make all symbols that would otherwise start with a .L
(or L on MachO) unnamed.

Some of these symbols still show up in the symbol table, but we can just
make them unnamed.

In order to make sure we produce identical results when going thought assembly,
all .L (not just the compiler produced ones), are now unnamed.

Running llc on llvm-as.opt.bc, the peak memory usage goes from 208.24MB to
205.57MB.

llvm-svn: 240130
2015-06-19 12:16:55 +00:00
Rafael Espindola b20fbb8b15 Refactor padding writing into a helper function.
llvm-svn: 239174
2015-06-05 18:21:00 +00:00
Rafael Espindola 7830fc83be Save a map lookup. NFC.
llvm-svn: 239168
2015-06-05 17:54:25 +00:00
Jim Grosbach 56ed0bb111 MC: Clean up the naming for MCMachObjectWriter. NFC.
s/ExecutePostLayoutBinding/executePostLayoutBinding/
s/ComputeSymbolTable/computeSymbolTable/
s/BindIndirectSymbols/bindIndirectSymbols/
s/RecordTLVPRelocation/recordTLVPRelocation/
s/RecordScatteredRelocation/recordScatteredRelocation/
s/WriteLinkerOptionsLoadCommand/writeLinkerOptionsLoadCommand/
s/WriteLinkeditLoadCommand/writeLinkeditLoadCommand/
s/WriteNlist/writeNlist/
s/WriteDysymtabLoadCommand/writeDysymtabLoadCommand/
s/WriteSymtabLoadCommand/writeSymtabLoadCommand/
s/WriteSection/writeSection/
s/WriteSegmentLoadCommand/writeSegmentLoadCommand/
s/WriteHeader/writeHeader/

llvm-svn: 239119
2015-06-04 23:25:54 +00:00
Jim Grosbach 36e60e9127 MC: Clean up naming in MCObjectWriter. NFC.
s/WriteObject/writeObject/
s/RecordRelocation/recordRelocation/
s/IsSymbolRefDifferenceFullyResolved/isSymbolRefDifferenceFullyResolved/
s/Write8/write8/
s/WriteLE16/writeLE16/
s/WriteLE32/writeLE32/
s/WriteLE64/writeLE64/
s/WriteBE16/writeBE16/
s/WriteBE32/writeBE32/
s/WriteBE64/writeBE64/
s/Write16/write16/
s/Write32/write32/
s/Write64/write64/
s/WriteZeroes/writeZeroes/
s/WriteBytes/writeBytes/

llvm-svn: 239108
2015-06-04 22:24:41 +00:00
Rafael Espindola 57c8083272 Remove unused argument. NFC.
llvm-svn: 239092
2015-06-04 20:55:49 +00:00
Rafael Espindola a401eee22f Omit unused section symbols from the symbol table.
Section symbols exist as an optimization: instead of having multiple relocations
point to different symbols, many of them can point to a single section symbol.

When that optimization is unused, a section symbol is also unused and adds no
extra information to the object file.

This saves a bit of space on the object files and makes the output of
llvm-objdump -t easier to read and consequently some tests get quite a bit
simpler.

llvm-svn: 239045
2015-06-04 15:33:30 +00:00
Rafael Espindola 8c006ee385 Bring back r239006 with a fix.
The fix is just that getOther had not been updated for packing the st_other
values in fewer bits and could return spurious values:

-  unsigned Other = (getFlags() & (0x3f << ELF_STO_Shift)) >> ELF_STO_Shift;
+  unsigned Other = (getFlags() & (0x7 << ELF_STO_Shift)) >> ELF_STO_Shift;

Original message:

Pack the MCSymbolELF bit fields into MCSymbol's Flags.

This reduces MCSymolfELF from 64 bytes to 56 bytes on x86_64.

While at it, also make getOther/setOther easier to use by accepting unshifted
STO_* values.

llvm-svn: 239012
2015-06-04 05:59:23 +00:00
Rafael Espindola a86ecee52b Revert "Pack the MCSymbolELF bit fields into MCSymbol's Flags."
This reverts commit r239006.

I am debugging the powerpc failures.

llvm-svn: 239010
2015-06-04 05:00:12 +00:00
Rafael Espindola d31203ae21 Pack the MCSymbolELF bit fields into MCSymbol's Flags.
This reduces MCSymolfELF from 64 bytes to 56 bytes on x86_64.

While at it, also make getOther/setOther easier to use by accepting unshifted
STO_* values.

llvm-svn: 239006
2015-06-04 02:32:20 +00:00
Rafael Espindola f8794ff29d Remove MCELFSymbolFlags.h. It is now internal to MCSymbolELF.
llvm-svn: 238996
2015-06-04 00:47:43 +00:00
Rafael Espindola 212fdde205 Remember if a weakref of a symbol has been used.
This avoids yet another last minute patching of the binding.

While at it, also simplify the weakref implementation a bit by not walking
past it in the expression evaluation.

llvm-svn: 238982
2015-06-03 21:52:06 +00:00
Rafael Espindola 8c52a9b0f6 Store whether a symbol is a comdat signature in MCSymbolELF.
With this getBinging can now return the correct answer for all cases not
involving a .symver and the elf writer doesn't need to patch it last minute.

llvm-svn: 238980
2015-06-03 21:41:59 +00:00
Rafael Espindola ada43f6337 Record in a MCSymbolELF if it has been used in a relocation.
No functionality change, just saves an on the side map.

llvm-svn: 238979
2015-06-03 21:30:10 +00:00
Rafael Espindola ef1e863c2c Simplify the logic in ELFObjectWriter::isInSymtab. NFC.
_GLOBAL_OFFSET_TABLE_ is not magical and we can now directly check for a
symbol never getting an explicit binding.

llvm-svn: 238978
2015-06-03 21:23:21 +00:00
Rafael Espindola 0ccf9b71f3 Pass a MCSymbolELF to a few ELF only functions. NFC.
llvm-svn: 238868
2015-06-02 21:30:13 +00:00
Rafael Espindola 95fb9b93ed Merge MCELF.h into MCSymbolELF.h.
Now that we have a dedicated type for ELF symbol, these helper functions can
become member function of MCSymbolELF.

llvm-svn: 238864
2015-06-02 20:38:46 +00:00
Rafael Espindola a869576008 Create a MCSymbolELF.
This create a MCSymbolELF class and moves SymbolSize since only ELF
needs a size expression.

This reduces the size of MCSymbol from 56 to 48 bytes.

llvm-svn: 238801
2015-06-02 00:25:12 +00:00
Rafael Espindola 4d37b2a259 Remove getData.
This completes the mechanical part of merging MCSymbol and MCSymbolData.

llvm-svn: 238617
2015-05-29 21:45:01 +00:00
Rafael Espindola beb6060a51 Remove the MCSymbolData typedef.
The getData member function is next.

llvm-svn: 238611
2015-05-29 20:41:47 +00:00
Rafael Espindola b5d316bfc3 Rename getOrCreateSymbolData to registerSymbol and return void.
Another step in merging MCSymbol and MCSymbolData.

llvm-svn: 238607
2015-05-29 20:21:02 +00:00
Rafael Espindola d31c0e2673 Fix build without asserts.
llvm-svn: 238597
2015-05-29 19:04:38 +00:00
Rafael Espindola e3b2acf274 Pass MCSymbols to the helper functions in MCELF.h.
llvm-svn: 238596
2015-05-29 18:47:23 +00:00
Rafael Espindola ece40ca43d Pass a MCSymbol to needsRelocateWithSymbol.
llvm-svn: 238589
2015-05-29 18:26:09 +00:00
Rafael Espindola 14672508b1 Move common symbol related information from MCSectionData to MCSymbol.
llvm-svn: 238583
2015-05-29 17:48:04 +00:00
Rafael Espindola 7c23cba65c Move SymbolSize from MCSymbolData to MCSymbol.
llvm-svn: 238580
2015-05-29 17:24:52 +00:00
Rafael Espindola f4b4430f8c Simplify now that symbols contain the correct section.
The complexity in here was because before r233995 variable symbols would report
the incorrect section.

llvm-svn: 238559
2015-05-29 15:07:27 +00:00
Rafael Espindola 10d238751e Fix ELFObjectWriter::isLocal for signature symbols.
And with that simplify the logic for inserting them in ExternalSymbolData or
LocalSymbolData.

No functionality change overall since the old code avoided the isLocal bug.

llvm-svn: 238555
2015-05-29 14:20:40 +00:00
Rafael Espindola bb35ebd189 Don't special case undefined symbol when deciding the symbol order.
ELF has no restrictions on where undefined symbols go relative to other defined
symbols. In fact, gas just sorts them together. Do the same.

This was there since r111174 probably just because the MachO writer has it.

llvm-svn: 238513
2015-05-28 21:59:34 +00:00
Rafael Espindola 3a5d3cce80 Remove a trivial forwarding function. NFC.
llvm-svn: 238506
2015-05-28 21:36:02 +00:00
Rafael Espindola 5e9ed90279 Inline trivial method. NFC.
llvm-svn: 238492
2015-05-28 20:53:09 +00:00
Rafael Espindola e48421f6fc Remove structure field that can be computed just before use.
llvm-svn: 238480
2015-05-28 20:25:29 +00:00
Rafael Espindola d7f10f0576 Avoid warnings when building without asserts.
llvm-svn: 238479
2015-05-28 20:19:31 +00:00
Rafael Espindola cfbd35c9ad Move these vectors to the only function where they are used.
llvm-svn: 238477
2015-05-28 20:11:34 +00:00