Commit Graph

24 Commits

Author SHA1 Message Date
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
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
Nico Weber 67e715ff7d Revert 240130, it caused crashes (repro in PR23900).
llvm-svn: 240193
2015-06-19 23:43:47 +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 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 75d5b5495f Fix the interpretation of a 0 st_name.
The ELF spec is very clear:

-----------------------------------------------------------------------------
If the value is non-zero, it represents a string table index that gives the
symbol name. Otherwise, the symbol table entry has no name.
--------------------------------------------------------------------------

In particular, a st_name of 0 most certainly doesn't mean that the symbol has
the same name as the section.

llvm-svn: 238899
2015-06-03 05:14:22 +00:00
Rafael Espindola 3b5ee55804 Don't include an invalid symbol in the symbol table.
The symbol table itself has no relocations, so it is not possible to represent
things like

a = undefined + 1

With the patch we just omit these variables. That matches the behaviour of the
gnu assembler.

llvm-svn: 207419
2014-04-28 13:39:57 +00:00
Rafael Espindola 407f5be3cc List the entire symbol table in this test.
This will allow us to extend this test to show that other symbols don't
show up in the symbol table.

llvm-svn: 207418
2014-04-28 13:26:35 +00:00
Rafael Espindola cfee7efde9 Teach llvm-readobj to print human friendly description of reserved sections.
llvm-svn: 204584
2014-03-24 05:00:34 +00:00
Nico Rieck ba848e3bca Replace coff-/elf-dump with llvm-readobj
llvm-svn: 179361
2013-04-12 04:06:46 +00:00
Rafael Espindola 9bc32a96be print st_shndx with the correct number of bits.
llvm-svn: 136880
2011-08-04 15:50:13 +00:00
Rafael Espindola 9528995e3f print st_other with the correct number of bits.
llvm-svn: 136877
2011-08-04 15:38:19 +00:00
Rafael Espindola 96df560ce1 print st_type with the correct number of bits.
llvm-svn: 136875
2011-08-04 15:24:00 +00:00
Rafael Espindola 79ef75dc49 Print st_bind with the correct number of bits.
llvm-svn: 136874
2011-08-04 15:10:35 +00:00
Rafael Espindola 1b282e7e49 Another counter goes decimal.
llvm-svn: 136871
2011-08-04 14:27:46 +00:00
Roman Divacky e15f591de4 Print all 64bits for st_value and st_size. Adjust tests accordingly.
llvm-svn: 122263
2010-12-20 20:49:43 +00:00
Rafael Espindola 45834a0065 Be more strict on when we produce an undefined reference. In gas a file with
just

.type   foo,@object

will produce an undefined reference to foo. On the other hand, a file with
just

.weakref bar, foo

will not. It is somewhat hard to support both in MC since both statements
should create the symbols. It should be possible if we really need to by
adding to the flags, but hopefully that is not necessary.

With this patch we do not produce a undefined reference in any of those cases.
The assembly file needs an actual use for the undefined reference to be
present.

This is in preparation for a patch implementing .weakref.

llvm-svn: 117735
2010-10-29 23:09:31 +00:00
Jason W Kim e8b3711ae9 Fixing r116753 r116756 r116777
The failures in r116753 r116756 were caused by a python issue -
Python likes to append 'L' suffix to stringified numbers if the number
is larger than a machine int. Unfortunately, this causes a divergence of
behavior between 32 and 64 bit python versions.

I re-crafted elf-dump/common_dump to take care of these issues by:

1. always printing 0x (makes for easy sed/regex)
2. always print fixed length (exactly 2 + numBits/4 digits long)
   by mod ((2^numBits) - 1)
3. left-padded with '0'

There is a residual common routine that is also used by
macho-dump (dataToHex) , so I left the 'section_data' test values alone.

llvm-svn: 116823
2010-10-19 17:39:10 +00:00
Eric Christopher eac5e381cc Speculatively revert 116753 and 116756 to attempt to fix the bots.
llvm-svn: 116777
2010-10-19 00:19:49 +00:00
Jason W Kim eae048885d Changed elf-dump to output hex format by default.
Also updated tests. 

llvm-svn: 116753
2010-10-18 21:32:41 +00:00
Rafael Espindola bee6e9f8e0 Remove some code duplication.
llvm-svn: 116484
2010-10-14 16:34:44 +00:00
Rafael Espindola 259bcdad06 Tests that now pass.
llvm-svn: 115622
2010-10-05 15:43:32 +00:00
Rafael Espindola 01d20a76fe On elf, undefined symbols can start with .L.
llvm-svn: 114958
2010-09-28 16:19:11 +00:00