Commit Graph

646 Commits

Author SHA1 Message Date
Rafael Espindola 5904e12bfa 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.

llvm-svn: 205076
2014-03-29 06:26:49 +00:00
Rafael Espindola c03f44ca8a Remove another unused argument.
llvm-svn: 204961
2014-03-27 20:49:35 +00:00
Rafael Espindola 9ab380122a Remove unused argument.
llvm-svn: 204956
2014-03-27 20:41:17 +00:00
Richard Sandiford 5676585886 [SystemZ] Use "let Predicates =" for blocks of new instructions
...instead of a separate Requires for each one.  This style was already
used in some places and seems more compact.

No behavioral change intended.

llvm-svn: 204452
2014-03-21 11:04:54 +00:00
Richard Sandiford dc6c2c953d [SystemZ] Add support for z196 float<->unsigned conversions
These complement the older float<->signed instructions.

llvm-svn: 204451
2014-03-21 10:56:30 +00:00
Rafael Espindola 7fadc0ea7d 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.

llvm-svn: 204294
2014-03-20 02:12:01 +00:00
Richard Sandiford 95bc5f92ee [SystemZ] Move sign_extend optimization to PerformDAGCombine
The target was marking SIGN_EXTEND as Custom because it wanted to optimize
certain sign-extended shifts.  In all other respects the extension is Legal,
so it'd be better to do the optimization in PerformDAGCombine instead.

No functional change intended.

llvm-svn: 203234
2014-03-07 11:34:35 +00:00
Rafael Espindola b1f25f1b93 Replace PROLOG_LABEL with a new CFI_INSTRUCTION.
The old system was fairly convoluted:
* A temporary label was created.
* A single PROLOG_LABEL was created with it.
* A few MCCFIInstructions were created with the same label.

The semantics were that the cfi instructions were mapped to the PROLOG_LABEL
via the temporary label. The output position was that of the PROLOG_LABEL.
The temporary label itself was used only for doing the mapping.

The new CFI_INSTRUCTION has a 1:1 mapping to MCCFIInstructions and points to
one by holding an index into the CFI instructions of this function.

I did consider removing MMI.getFrameInstructions completelly and having
CFI_INSTRUCTION own a MCCFIInstruction, but MCCFIInstructions have non
trivial constructors and destructors and are somewhat big, so the this setup
is probably better.

The net result is that we don't create temporary labels that are never used.

llvm-svn: 203204
2014-03-07 06:08:31 +00:00
Richard Sandiford b4d67b593e [SystemZ] Remove "virtual" from override methods
Also fix a couple of cases where "override" was missing.  No behavioural
change intended.

llvm-svn: 203110
2014-03-06 12:03:36 +00:00
Richard Sandiford 21f5d68a17 [SystemZ] Use "auto" for cast results
No functional change intended.

llvm-svn: 203106
2014-03-06 11:22:58 +00:00
Richard Sandiford 28c111ec8a [SystemZ] Use "for (auto" a bit
Just the simple cases for now.  There were a few knock-on changes of
MachineBasicBlock *s to MachineBasicBlock &s.  No functional change intended.

llvm-svn: 203105
2014-03-06 11:00:15 +00:00
Richard Sandiford c231269ff9 [SystemZ] Update namespace formatting to match current guidelines
No functional change intended.

llvm-svn: 203103
2014-03-06 10:38:30 +00:00
Benjamin Kramer b6d0bd48bd [C++11] Replace llvm::next and llvm::prior with std::next and std::prev.
Remove the old functions.

llvm-svn: 202636
2014-03-02 12:27:27 +00:00
Craig Topper 73156025e0 Switch all uses of LLVM_OVERRIDE to just use 'override' directly.
llvm-svn: 202621
2014-03-02 09:09:27 +00:00
Rafael Espindola 4998280fdf Just returning false is the default.
llvm-svn: 200890
2014-02-06 00:03:15 +00:00
Matt Arsenault 25793a3f22 Add address space argument to allowsUnalignedMemoryAccess.
On R600, some address spaces have more strict alignment
requirements than others.

llvm-svn: 200887
2014-02-05 23:15:53 +00:00
David Woodhouse 3fa98a65e9 Propagate MCSubtargetInfo through TableGen's getBinaryCodeForInstr()
llvm-svn: 200349
2014-01-28 23:13:18 +00:00
David Woodhouse 9784cef38d Explictly pass MCSubtargetInfo to MCCodeEmitter::EncodeInstruction()
llvm-svn: 200348
2014-01-28 23:13:07 +00:00
David Woodhouse e6c13e4abd Change MCStreamer EmitInstruction interface to take subtarget info
llvm-svn: 200345
2014-01-28 23:12:42 +00:00
Rafael Espindola e41383f899 Pass a MCSubtargetInfo down to the TargetStreamer creation.
With this the target streamers will be able to know the target features that
are in use.

llvm-svn: 200135
2014-01-26 06:38:58 +00:00
Rafael Espindola 24ea09ef7d Construct the MCStreamer before constructing the MCTargetStreamer.
This has a few advantages:
* Only targets that use a MCTargetStreamer have to worry about it.
* There is never a MCTargetStreamer without a MCStreamer, so we can use a
  reference.
* A MCTargetStreamer can talk to the MCStreamer in its constructor.

llvm-svn: 200129
2014-01-26 06:06:37 +00:00
Alp Toker cb40291100 Fix known typos
Sweep the codebase for common typos. Includes some changes to visible function
names that were misspelt.

llvm-svn: 200018
2014-01-24 17:20:08 +00:00
Richard Sandiford 32379b8141 [SystemZ] Optimize (sext (ashr (shl ...), ...))
...into (ashr (shl (anyext X), ...), ...), which requires one fewer
instruction.  The (anyext X) can sometimes be simplified too.

I didn't do this in DAGCombiner because widening shifts isn't a win
on all targets.

llvm-svn: 199114
2014-01-13 15:17:53 +00:00
Richard Sandiford 3875cb60f3 [SystemZ] Fix RNSBG bug introduced by r197802
The zext handling added in r197802 wasn't right for RNSBG.  This patch
restricts it to ROSBG, RXSBG and RISBG.  (The tests for RISBG were added
in r197802 since RISBG was the motivating example.)

llvm-svn: 198862
2014-01-09 11:28:53 +00:00
Rafael Espindola 894843cb4e Move the llvm mangler to lib/IR.
This makes it available to tools that don't link with target (like llvm-ar).

llvm-svn: 198708
2014-01-07 21:19:40 +00:00
Chandler Carruth 8a8cd2bab9 Re-sort all of the includes with ./utils/sort_includes.py so that
subsequent changes are easier to review. About to fix some layering
issues, and wanted to separate out the necessary churn.

Also comment and sink the include of "Windows.h" in three .inc files to
match the usage in Memory.inc.

llvm-svn: 198685
2014-01-07 11:48:04 +00:00
Rafael Espindola 58873566b3 Make the llvm mangler depend only on DataLayout.
Before this patch any program that wanted to know the final symbol name of a
GlobalValue had to link with Target.

This patch implements a compromise solution where the mangler uses DataLayout.
This way, any tool that already links with Target (llc, clang) gets the exact
behavior as before and new IR files can be mangled without linking with Target.

With this patch the mangler is constructed with just a DataLayout and DataLayout
is extended to include the information the Mangler needs.

llvm-svn: 198438
2014-01-03 19:21:54 +00:00
Richard Sandiford 002019a285 Fix typo.
llvm-svn: 197986
2013-12-24 15:22:39 +00:00
Richard Sandiford 41350a52ca [SystemZ] Use interlocked-access 1 instructions for CodeGen
...namely LOAD AND ADD, LOAD AND AND, LOAD AND OR and LOAD AND EXCLUSIVE OR.
LOAD AND ADD LOGICAL isn't really separately useful for LLVM.

I'll look at adding reusing the CC results in new year.

llvm-svn: 197985
2013-12-24 15:18:04 +00:00
Richard Sandiford 45645a2c1c [SystemZ] Add MC support for interlocked-access 1 instructions
llvm-svn: 197984
2013-12-24 15:14:05 +00:00
Richard Sandiford 83a0b6abd0 [SystemZ] Optimize comparisons with truncated extended loads
If the extension of a loaded value is compared against zero and used in
other arithmetic, InstCombine will change the comparison to use the
unextended load.  It's also possible that the comparison could be against
the unextended load from the outset.

In DAG form this becomes a truncation of an extending load.  We want to
strip the truncation if possible so that we can use load-and-test instructions.

llvm-svn: 197804
2013-12-20 11:56:02 +00:00
Richard Sandiford 220ee49bce [SystemZ] Extend RISBG optimization
The handling of ANY_EXTEND and ZERO_EXTEND was too strict.  In this context
we can treat ZERO_EXTEND in much the same way as an AND and then also handle
outermost ZERO_EXTENDs.

I couldn't find a test that benefited from the ANY_EXTEND change, but it's
more obvious to write it this way once SIGN_EXTEND and ZERO_EXTEND are
handled differently.

llvm-svn: 197802
2013-12-20 11:49:48 +00:00
Rafael Espindola 8afbb28cea On DataLayout, omit the default of p:64:64:64.
llvm-svn: 197397
2013-12-16 17:15:29 +00:00
Richard Sandiford 0847c450b6 [SystemZ] Optimize X [!=]= Y in cases where X - Y or Y - X is also computed
In those cases it's better to compare the result of the subtraction
against zero.

llvm-svn: 197239
2013-12-13 15:50:30 +00:00
Richard Sandiford c3dc44781b [SystemZ] Make more use of TMHH
This originally came about after noticing that InstCombine turns
some of the TMHH (icmp (and...), ...) tests into plain comparisons.
Since there is no instruction to compare with a 64-bit immediate,
TMHH is generally better than an ordered comparison for the cases
that it can handle.

llvm-svn: 197238
2013-12-13 15:46:55 +00:00
Richard Sandiford 57485472e2 [SystemZ] Extend integer absolute selection
This patch makes more use of LPGFR and LNGFR.  It builds on top of
the LTGFR selection from r197234.  Most of the tests are motivated
by what InstCombine would produce.

llvm-svn: 197236
2013-12-13 15:35:00 +00:00
Richard Sandiford d420f7344f [SystemZ] Add a structure to represent a selected comparison
...in an attempt to rein back the increasingly complex selection code.
A knock-on effect is that ICmpType is exposed from the outset, which
slightly simplifies adjustSubwordCmp.

The code is no piece of art even after this change, but at least it should
be slightly better.  No behavioral change intended.

llvm-svn: 197235
2013-12-13 15:28:45 +00:00
Richard Sandiford bd2f0e9cd0 [SystemZ] Make more use of LTGFR
InstCombine turns (sext (trunc)) into (ashr (shl)), then converts any
comparison of the ashr against zero into a comparison of the shl against zero.
This makes sense in itself, but we want to undo it for z, since the sign-
extension instruction has a CC-setting form.

I've included tests for both the original and InstCombined variants,
but the former already worked.  The patch fixes the latter.

llvm-svn: 197234
2013-12-13 15:07:39 +00:00
Rafael Espindola 3db958387f Simplify the SystemZ datalayout string.
Reviewed by Richard Sandiford.

llvm-svn: 197170
2013-12-12 17:30:07 +00:00
Rafael Espindola e8f4d58700 Use "a" instead of "a0" in DataLayout.
It means exactly the same and is just a bit shorter.

llvm-svn: 197169
2013-12-12 17:21:51 +00:00
Richard Sandiford 73170f8488 [SystemZ] Optimize fcmp X, 0 in cases where X is also negated
In such cases it's often better to test the result of the negation instead,
since the negation also sets CC.

llvm-svn: 197032
2013-12-11 11:45:08 +00:00
NAKAMURA Takumi 8bc9bfaa5a Prune redundant dependencies in LLVMBuild.txt.
llvm-svn: 196988
2013-12-11 00:30:57 +00:00
Richard Sandiford bef3d7af2b Add TargetLowering::prepareVolatileOrAtomicLoad
One unusual feature of the z architecture is that the result of a
previous load can be reused indefinitely for subsequent loads, even if
a cache-coherent store to that location is performed by another CPU.
A special serializing instruction must be used if you want to force
a load to be reattempted.

Since volatile loads are not supposed to be omitted in this way,
we should insert a serializing instruction before each such load.
The same goes for atomic loads.

The patch implements this at the IR->DAG boundary, in a similar way
to atomic fences.  It is a no-op for targets other than SystemZ.

llvm-svn: 196906
2013-12-10 10:49:34 +00:00
Richard Sandiford 9afe613d12 Add TargetLowering::prepareVolatileOrAtomicLoad
One unusual feature of the z architecture is that the result of a
previous load can be reused indefinitely for subsequent loads, even if
a cache-coherent store to that location is performed by another CPU.
A special serializing instruction must be used if you want to force
a load to be reattempted.

Since volatile loads are not supposed to be omitted in this way,
we should insert a serializing instruction before each such load.
The same goes for atomic loads.

The patch implements this at the IR->DAG boundary, in a similar way
to atomic fences.  It is a no-op for targets other than SystemZ.

llvm-svn: 196905
2013-12-10 10:36:34 +00:00
NAKAMURA Takumi 396d4d3c7e Add proper dependencies to LLVMBuild.txt in llvm/lib.
I'll prune redundant deps in LLVMBuild.txt, later.

llvm-svn: 196881
2013-12-10 05:39:34 +00:00
Richard Sandiford 198ddf83c1 [SystemZ] Use LOAD AND TEST for comparisons with -0
...since it os equivalent to comparison with +0.

llvm-svn: 196580
2013-12-06 09:59:12 +00:00
Richard Sandiford 7b4118a0fc [SystemZ] Extend the use of C(L)GFR
instcombine prefers to put extended operands first, so this patch
handles that case for C(L)GFR.

llvm-svn: 196579
2013-12-06 09:56:50 +00:00
Richard Sandiford 48ef6abddc [SystemZ] Optimize selects between 0 and -1
Since z has no setcc instruction as such, the choice of setBooleanContents
is a bit arbitrary.  Currently it's set to ZeroOrOneBooleanContent,
so we produced a branch-free form when selecting between 0 and 1,
but not when selecting between 0 and -1.  This patch handles the latter
case too.

At some point I'd like to measure whether it's better to use conditional
moves for constant selects on z196, but that's future work.

llvm-svn: 196578
2013-12-06 09:53:09 +00:00
Richard Sandiford ccc2a7c1a0 [SystemZ] Fix choice of known-zero mask in insertion optimization
The backend converts 64-bit ORs into subreg moves if the upper 32 bits
of one operand and the low 32 bits of the other are known to be zero.
It then tries to peel away redundant ANDs from the upper 32 bits.

Since AND masks are canonicalized to exclude known-zero bits,
the test ORs the mask and the known-zero bits together before
checking for redundancy.  The problem was that it was using the
wrong node when checking for known-zero bits, so could drop ANDs
that were still needed.

llvm-svn: 196267
2013-12-03 11:01:54 +00:00
Rafael Espindola 5113d166f5 Refactor the setting of PrivateGlobalPrefix.
No functionality change.

llvm-svn: 196170
2013-12-02 23:39:26 +00:00