Commit Graph

305 Commits

Author SHA1 Message Date
Rafael Espindola
4551671908 Avoid revocations when possible.
This is a small targeted fix for pr20119. The code needs quiet a bit of
refactoring and I added some FIXMEs about it, but I want to get the testcase
passing first.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212101 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-01 14:34:30 +00:00
Rafael Espindola
88a564f55e Allow using .cfi_startproc without a leading symbol.
This is possible now that we don't produce .eh symbols. This fixes pr19430.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211502 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-23 15:34:32 +00:00
NAKAMURA Takumi
fe755c57f8 Introduce a Lit feature "debug_frame" and apply it to llvm/test/MC/ELF/cfi-version.ll.
.debug_frame is not emitted for targeting Windows x64.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211466 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-22 12:35:39 +00:00
Weiming Zhao
09f104fc32 Report error for non-zero data in .bss
User may initialize a var with non-zero value and specify .bss section.
E.g. : int a __attribute__((section(".bss"))) = 2;

This patch converts an assertion to error report for better user
experience.

Differential Revision: http://reviews.llvm.org/D4199


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211455 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-22 00:33:44 +00:00
Eric Christopher
74fc19ebf4 Fix this test a little harder - use llc_dwarf to make sure we don't
try to execute it on windows.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211298 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-19 19:26:42 +00:00
Eric Christopher
cadf0f68e4 Relax this test a bit, we don't need the full contents of the
frame section to match, just the version for this test.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211293 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-19 18:36:15 +00:00
Oliver Stannard
bb804ee909 Emit DWARF3 call frame information when DWARF3+ debug info is requested
Currently, llvm always emits a DWARF CIE with a version of 1, even when emitting
DWARF 3 or 4, which both support CIE version 3. This patch makes it emit the
newer CIE version when we are emitting DWARF 3 or 4. This will not reduce
compatibility, as we already emit other DWARF3/4 features, and is worth doing as
the DWARF3 spec removed some ambiguities in the interpretation of call frame
information.

It also fixes a minor bug where the "return address" field of the CIE was
encoded as a ULEB128, which is only valid when the CIE version is 3. There are
no test changes for this, because (as far as I can tell) none of the platforms
that we test have a return address register with a DWARF register number >127.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211272 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-19 15:39:33 +00:00
Alp Toker
8aeca44558 Reduce verbiage of lit.local.cfg files
We can just split targets_to_build in one place and make it immutable.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210496 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-09 22:42:55 +00:00
Alp Toker
2aa472f4bd Re-enable ARM ELF tests
r210408 inadvertently disabled them when X86 is not selected.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210412 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-08 02:46:02 +00:00
Saleem Abdulrasool
e231836fe4 test: move some tests into ARM directory
Rather than requiring ARM support for the ELF tests (which is odd), move the
tests that require ARM into a subdirectory to use lit to disable them if the
support is not present.  Play this game to prevent disabling the ELF tests on
the Windows build bots as they have caught issues in the past with interactions
between various platforms.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210408 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-08 01:04:05 +00:00
Saleem Abdulrasool
eb5f5ae200 MC: make ELF .type handling more GNU AS compatible
GAS documents the .type directive as having an optional comma following the key
symbol name when using the STT_<TYPE_IN_UPPER_CASE> form.  However, it treats
the comma as optional in all cases.  This makes the IAS support both forms of
inputs.  Furthermore, the prefixed forms take either the upper case name or the
lower case alias.

The tests are split into two separate sets as the hash character serves as a
comment character on x86, which is tested in the second set by using arm-elf
which uses the at symbol as a comment character.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210407 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-08 00:34:34 +00:00
Eric Christopher
d1b5bdaebd Move MCOptions that aren't shared between programs into their specific
program and have them initialize the MCOptions struct explicitly.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@209321 91177308-0d34-0410-b5e6-96231b3b80d8
2014-05-21 21:05:09 +00:00
Rafael Espindola
930ca98433 Fix pr19645.
The fix itself is fairly simple: move getAccessVariant to MCValue so that we
replace the old weak expression evaluation with the far more general
EvaluateAsRelocatable.

This then requires that EvaluateAsRelocatable stop when it finds a non
trivial reference kind. And that in turn requires the ELF writer to look
harder for weak references.

Last but not least, this found a case where we were being bug by bug
compatible with gas and accepting an invalid input. I reported pr19647
to track it.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207920 91177308-0d34-0410-b5e6-96231b3b80d8
2014-05-03 19:57:04 +00:00
Oliver Stannard
5604ab9da4 Record the DWARF version in MCContext
Record the DWARF version in MCContext, and use it when
emitting the dwarf version into the debug info.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207739 91177308-0d34-0410-b5e6-96231b3b80d8
2014-05-01 08:46:02 +00:00
James Molloy
d96bbedc6a Move a testcase from ELF to ARM64, incorrectly placed in r207627.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207706 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-30 21:31:11 +00:00
James Molloy
6f327421c5 Add a testcase for r207627.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207697 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-30 20:06:26 +00:00
Hans Wennborg
a8febf2283 ELFObjectWriter: deduplicate suffices in strtab
We already do this for shstrtab, so might as well do it for strtab. This
extracts the string table building code into a separate class. The idea
is to use it for other object formats too.

I mostly wanted to do this for the general principle, but it does save a
little bit on object file size. I tried this on a clang bootstrap and
saved 0.54% on the sum of object file sizes (1.14 MB out of 212 MB for
a release build).

Differential Revision: http://reviews.llvm.org/D3533

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207670 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-30 16:25:02 +00:00
Rafael Espindola
41fb117905 Relax the test a bit.
It is not relevant where the symbol and section names are stored, just their
values.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207662 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-30 15:32:21 +00:00
Rafael Espindola
3dbcd2e69e Rename the test, it is testing the symver directive.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207658 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-30 15:27:44 +00:00
Rafael Espindola
1c509556ee Add an option for evaluating past symbols.
When evaluating an assembly expression for a relocation, we want to
stop at MCSymbols that are in the symbol table, even if they are variables.
This is needed since the semantics may require that the relocation use them.

That is not the case when computing the value of a symbol in the symbol table.
There are no relocations in this case and we have to keep going until we hit
a section or find out that the expression doesn't have an assembly time
value.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207445 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-28 20:53:11 +00:00
Rafael Espindola
0af058ff9c 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.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207419 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-28 13:39:57 +00:00
Rafael Espindola
086e9aaa55 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.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207418 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-28 13:26:35 +00:00
Rafael Espindola
c074b096d5 Produce an error instead of a crash in an expr we cannot represent.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207414 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-28 12:40:50 +00:00
Rafael Espindola
bc26ff9180 Handle _GLOBAL_OFFSET_TABLE_ in 64 bit mode.
With this MC is able to handle _GLOBAL_OFFSET_TABLE_ in 64 bit mode, which is
needed for medium and large code models.

This fixes pr19470.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206793 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-21 21:15:45 +00:00
David Blaikie
2e3463ec43 Compress debug sections only when beneficial.
Both ZLIB and the debug info compressed section header ("ZLIB" + the
size of the uncompressed data) take some constant overhead so in some
cases the compressed data is actually larger than the uncompressed data.
In these cases, just don't compress or rename the section at all.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206659 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-18 21:52:26 +00:00
David Blaikie
037da24c10 Update the fragments of symbols in compressed sections.
While unnamed relocations are already cached in side tables in
ELFObjectWriter::RecordRelocation, symbols still need their fragments
updated to refer to the newly compressed fragment (even if that fragment
isn't big enough to fit the offset). Even though we only create
temporary symbols in debug info sections this comes up in 32 bit builds
where even temporary symbols in mergeable sections (such as debug_str)
have to be emitted as named symbols.

I tried a few other ways to do this but they all didn't work for various
reasons:

1) Canonicalize the MCSymbolData in RecordRelocation, nulling out the
Fragment (so it didn't have to be updated by CompressDebugSection). This
doesn't work because some code relies on symbols having fragments to
indicate that they're defined, I think.

2) Canonicalize the MCSymbolData in RecordRelocation to be "first
fragment + absolute offset" so it would be cheaper to just test and
update the fragment in CompressDebugSections. This doesn't work because
the offset computed in RecordRelocation isn't that of the symbol's
fragment, it's the passed in fragment (I haven't figured out what that
fragment is - perhaps it's the location where the relocation is to be
written). And if the fragment offset has to be computed only for this
use we might as well just do it when we need to, in
CompressDebugSection.

I also added an assert to help catch this a bit more clearly, even
though it is UB. The test case improvements would either assert fail
and/or valgrind vail without the fix, even if they wouldn't necessarily
fail the FileCheck output.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206653 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-18 21:24:12 +00:00
Kaelyn Takata
de2b2a32f4 Fix up MCFixup::getAccessVariant to handle unary expressions.
This allows correct relocations to be generated for a symbolic
address that is being adjusted by a negative constant. Since r204294,
such expressions have triggered undefined behavior when LLVM was built
without assertions.

Credit goes to Rafael for this patch; I'm submitting it on his behalf
as he is on vacation this week.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206192 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-14 16:50:22 +00:00
David Blaikie
fe25521451 Reimplement debug info compression by compressing the whole section, rather than a fragment.
To support compressing the debug_line section that contains multiple
fragments (due, I believe, to variation in choices of line table
encoding depending on the size of instruction ranges in the actual
program code) we needed to support compressing multiple MCFragments in a
single pass.

This patch implements that behavior by mutating the post-relaxed and
relocated section to be the compressed form of its former self,
including renaming the section.

This is a more flexible (and less invasive, to a degree) implementation
that will allow for other features such as "use compression only if it's
smaller than the uncompressed data".

Compressing debug_frame would be a possible further extension to this
work, but I've left it for now. The hurdle there is alignment sections -
which might require going as far as to refactor
MCAssembler.cpp:writeFragment to handle writing to a byte buffer or an
MCObjectWriter (there's already a virtual call there, so it shouldn't
add substantial compile-time cost) which could in turn involve
refactoring MCAsmBackend::writeNopData to use that same abstraction...
which involves touching all the backends. This would remove the limited
handling of fragment writing seen in
ELFObjectWriter.cpp:getUncompressedData which would be nice - but it's
more invasive.

I did discover that I (perhaps obviously) don't need to handle
relocations when I rewrite the fragments - since the relocations have
already been applied and computed (and stored into
ELFObjectWriter::Relocations) by this stage (necessarily, because we
need to have written any immediate values or assembly-time relocations
into the data already before we compress it, which we have). The test
case doesn't necessarily cover that in detail - I can add more test
coverage if that's preferred.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205990 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-10 21:53:53 +00:00
David Blaikie
22f3236dd6 Revert debug info compression support.
To support compression for debug_line and debug_frame a different
approach is required. To simplify review, revert the old implementation
and XFAIL the test case. New implementation to follow shortly.

Reverts r205059 and r204958.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205989 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-10 21:53:47 +00:00
NAKAMURA Takumi
60db02b6fe X86MCAsmInfoGNUCOFF: Set PointerSize as 8 for targeting x64. It caused DW_LNE_set_address was misemitted on x64.
FIXME: I haven't investigate whether CalleeSaveStackSlotSize should be 8.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205772 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-08 15:28:50 +00:00
Rafael Espindola
5d853bf42d Work around gold bug http://sourceware.org/PR16794.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205416 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-02 12:15:20 +00:00
David Blaikie
a07c1ab4e6 DebugInfo: Avoid creating unnecessary/empty line tables and remove the special case of '0' in DwarfCompileUnit::initStmtList by just always using a label difference
This moves one case of raw text checking down into the MCStreamer
interfaces in the form of a virtual function, even if we ultimately end
up consolidating on the one-or-many line tables issue one day, this is
nicer in the interim. This just generally streamlines a bunch of use
cases into a common code path.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205287 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-01 08:07:52 +00:00
David Blaikie
5b2de5dd3d DebugInfo: Emit relocation to debug_line section when emitting asm for asm
I don't think this is reachable by any frontend (why would you transform
asm to asm+debug info?) but it helps tidy up some of this code, avoid
the weird special case of "emit the first CU, store the label, then emit
the rest" in MCDwarfLineTable::Emit by instead having the
DWARF-for-assembly case use the same codepath as DwarfDebug.cpp, by
registering the label of the debug_line section, thus causing it to be
emitted. (with a special case in asm output to just emit the label since
asm output uses the .loc directives, etc, rather than the debug_loc
directly)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205286 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-01 07:35:52 +00:00
NAKAMURA Takumi
2afefa27b3 llvm/test/MC/ELF/nocompression.s: Loosen an expression to match "llvm-mc.EXE".
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205148 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-30 14:04:00 +00:00
Logan Chien
a68f166d60 llvm-mc: Fix build breakage caused by r205050.
When LLVM is not built with zlib, nocompression.s will test
for the error message.  But this test case will cause breakage
because the exit code is non-zero.  This commit fix this issue
by adding "not" to the command.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205102 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-29 15:10:22 +00:00
Rafael Espindola
224dbf4aec Completely rewrite ELFObjectWriter::RecordRelocation.
I started trying to fix a small issue, but this code has seen a small fix too
many.

The old code was fairly convoluted. Some of the issues it had:

* It failed to check if a symbol difference was in the some section when
  converting a relocation to pcrel.
* It failed to check if the relocation was already pcrel.
* The pcrel value computation was wrong in some cases (relocation-pc.s)
* It was missing quiet a few cases where it should not convert symbol
  relocations to section relocations, leaving the backends to patch it up.
* It would not propagate the fact that it had changed a relocation to pcrel,
  requiring a quiet nasty work around in ARM.
* It was missing comments.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205076 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-29 06:26:49 +00:00
David Blaikie
1fc0d63775 Debug Compression: Avoid compression debug_frame for now
Turns out debug_frame does use multiple fragments, so it doesn't
compress correctly with the current approach. Disable compressing it for
now while I figure out what's the best solution for it.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205059 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-28 21:48:31 +00:00
David Blaikie
4a9c2585ab llvm-mc: error when -compress-debug-sections is requested and zlib is not linked
This is a bit of a stab in the dark, since I have zlib on my machine.
Just going to bounce it off the bots & see if it sticks.

Do we have some convention for negative REQUIRES: checks? Or do I just
need to add a feature like I've done here?

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205050 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-28 20:45:24 +00:00
David Blaikie
b91f51161f Only test compression when linked with zlib.
I'll implement error handling and a negative test in both llvm-mc and
Clang soon.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205016 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-28 17:04:53 +00:00
David Blaikie
0a0c4cc56f DebugInfo: Support for compressed debug info sections
1) When creating a .debug_* section and instead create a .zdebug_
   section.
2) When creating a fragment in a .zdebug_* section, make it a compressed
   fragment.
3) When computing the size of a compressed section, compress the data
   and use the size of the compressed data.
4) Emit the compressed bytes.

Also, check that only if a section has a compressed fragment, then that
is the only fragment in the section.

Assert-fail if the fragment's data is modified after it is compressed.

Initial review on llvm-commits by Eric Christopher and Rafael Espindola.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204958 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-27 20:45:58 +00:00
Rafael Espindola
e459f72ee0 Correctly propagates st_size.
This also finally removes a bogus call to AliasedSymbol.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204883 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-27 00:28:24 +00:00
Rafael Espindola
3008f80562 Correctly detect if a symbol uses a reserved section index or not.
The logic was incorrect for variables, causing them to end up in the wrong
section if the section had an index >= 0xff00.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204771 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-26 00:16:43 +00:00
Rafael Espindola
81c66bcc13 Create .symtab_shndxr only when needed.
We need .symtab_shndxr if and only if a symbol references a section with an
index >= 0xff00.

The old code was trying to figure out if the section was needed ahead of time,
making it a fairly dependent on the code actually writing the table. It was
also somewhat conservative and would create the section in cases where it was
not needed.

If I remember correctly, the old structure was there so that the sections were
created in the same order gas creates them. That was valuable when MC's support
for ELF was new and we tested with elf-dump.py.

This patch refactors the symbol table creation to another class and makes it
obvious that .symtab_shndxr is really only created when we are about to output
a reference to a section index >= 0xff00.

While here, also improve the tests to use macros. One file is one section
short of needing .symtab_shndxr, the second one has just the right number.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204769 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-25 23:44:25 +00:00
Rafael Espindola
2236f9348d Teach llvm-readobj to print human friendly description of reserved sections.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204584 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-24 05:00:34 +00:00
Rafael Espindola
0259b8e14f Add back tests that were reverted in r204203.
They pass again with the fix in r204581.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204582 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-24 03:48:15 +00:00
Rafael Espindola
0bce3343cc Propagate section from base to derived symbol.
We were already propagating the section in

a = b

With this patch we also propagate it for

a = b + 1

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204581 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-24 03:43:21 +00:00
Rafael Espindola
4ff2dadebe Propagate types from symbol to aliases.
This is similar, but not identical to what gas does. The logic in MC is to just
compute the symbol table after parsing the entire file. GAS is mixed, given

.type b, @object
a = b
b:
.type b, @function

It will propagate the change and make 'a' a function. Given

.type b, @object
b:
a = b
.type b, @function

the type of 'a' is still object.

Since we do the computation in the end, we produce a function in both cases.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204555 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-23 03:33:20 +00:00
Rafael Espindola
a60f719c8d Fix the value computation in
sym_a:
sym_d = sym_a + 1

This is the smallest fix I was able to extract from what got reverted in
r204203.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204527 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-21 22:00:29 +00:00
Rafael Espindola
0a70f9b3b9 Look through variables when computing relocations.
Given

bar = foo + 4
	.long bar

MC would eat the 4. GNU as includes it in the relocation. The rule seems to be
that a variable that defines a symbol is used in the relocation and one that
does not define a symbol is evaluated and the result included in the relocation.

Fixing this unfortunately required some other changes:

* Since the variable is now evaluated, it would prevent the ELF writer from
  noticing the weakref marker the elf streamer uses. This patch then replaces
  that with a VariantKind in MCSymbolRefExpr.

* Using VariantKind then requires us to look past other VariantKind to see

	.weakref	bar,foo
	call	bar@PLT

  doing this also fixes

	zed = foo +2
	call zed@PLT

  so that is a good thing.

* Looking past VariantKind means that the relocation selection has to use
  the fixup instead of the target.

This is a reboot of the previous fixes for MC. I will watch the sanitizer
buildbot and wait for a build before adding back the previous fixes.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204294 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-20 02:12:01 +00:00
Rafael Espindola
94ec09ae32 Make the test harder by using a non-zero offset.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204205 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-19 00:26:58 +00:00