Commit Graph

17905 Commits

Author SHA1 Message Date
Duncan P. N. Exon Smith
ca3b3d5e2c AsmPrinter: Stop creating DebugLocs
While looking at a heap profile of a clang LTO bootstrap with -g, I
noticed that 2.2% of memory in an `llvm-lto` of clang is from calling
`DebugLoc::get()` in `collectVariableInfo()` (accounting for ~40% of
memory used for `MDLocation`s).

I suspect this was introduced by r226736, whose goal was to prevent
uniquing of `DebugLoc`s (goal achieved, if so).

There's no reason we need a `DebugLoc` here at all -- it was just being
used for (in)convenient API -- so the fix is to pass the scope and
inlined-at directly to `LexicalScopes::findInlinedScope()`.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229459 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-17 00:02:27 +00:00
Matthias Braun
2a43652f3b RegisterCoalescer: Don't rematerialize subregister definitions.
We cannot simply rematerialize instructions which only defining a
subregister, as the final value also depends on the previous
instructions.

This fixes test/CodeGen/R600/subreg-coalescer-bug.ll with subreg
liveness enabled.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229444 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-16 22:05:17 +00:00
Matthias Braun
1f67650f77 RegisterCoalescer: Do not look for regclass of IMPLICIT_DEF.
IMPLICIT_DEF is a generic instruction and has no (fixed) output register
class defined. The rematerialization code of the register coalescer
should not scan the instruction description for a register class.

This fixes a problem showing up in
test/CodeGen/R600/subreg-coalescer-crash.ll with subregister liveness
enabled.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229443 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-16 22:05:12 +00:00
Mehdi Amini
2deb1d0b54 SelectionDAG: fold (fp_to_u/sint (s/uint_to_fp)) here too
Update SPARC tests to match.

From: Fiona Glaser <fglaser@apple.com>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229438 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-16 21:47:58 +00:00
Matthias Braun
6f75026706 RegisterCoalescer: Improve previous fix for wrong def after.
The previous fix in r225503 was needlessly complicated. The problem goes
away as well if the arguments to MergeValueNumberInto are supplied in the
correct order.
This was previously missed because the existing code already had the
wrong order but an additional later Merge was hiding the bug for the
main liverange VNI.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229424 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-16 19:34:27 +00:00
Aaron Ballman
7fcd74585a MSVC 2013 supports std::forward_as_tuple, while MSVC 2012 did not; so we can move to using the improved API.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229414 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-16 18:21:19 +00:00
Andrew Trick
4f7d60c1ea AArch64: Safely handle the incoming sret call argument.
This adds a safe interface to the machine independent InputArg struct
for accessing the index of the original (IR-level) argument. When a
non-native return type is lowered, we generate the hidden
machine-level sret argument on-the-fly. Before this fix, we were
representing this argument as OrigArgIndex == 0, which is an outright
lie. In particular this crashed in the AArch64 backend where we
actually try to access the type of the original argument.

Now we use a sentinel value for machine arguments that have no
original argument index. AArch64, ARM, Mips, and PPC now check for this
case before accessing the original argument.

Fixes <rdar://19792160> Null pointer assertion in AArch64TargetLowering

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229413 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-16 18:10:47 +00:00
Michael Kuperstein
012d5929f1 Fix quoting of #pragma comment for MS compat, LLVM part.
For #pragma comment(linker, ...) MSVC expects the comment string to be quoted, but for #pragma comment(lib, ...) the compiler itself quotes the library name.
Since this distinction disappears by the time the directive reaches the backend, move quoting for the "lib" version to the frontend.

Differential Revision: http://reviews.llvm.org/D7652

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229375 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-16 11:57:17 +00:00
Aaron Ballman
66981fe208 Removing LLVM_DELETED_FUNCTION, as MSVC 2012 was the last reason for requiring the macro. NFC; LLVM edition.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229340 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-15 22:54:22 +00:00
Chandler Carruth
72753f87f2 [SDAG] Teach the SelectionDAG to canonicalize vector shuffles of splats
directly into blends of the splats.

These patterns show up even very late in the vector shuffle lowering
where we don't have any chance for DAG combining to kick in, and
blending is a tremendously simpler operation to model. By coercing the
shuffle into a blend we can much more easily match and lower shuffles of
splats.

Immediately with this change there are significantly more blends being
matched in the x86 vector shuffle lowering.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229308 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-15 12:18:12 +00:00
Chandler Carruth
5ee516549f [x86] Fix PR22377, a regression with the new vector shuffle legality
test.

This was just a matter of the DAG combine for vector shuffles being too
aggressive. This is a bit of a grey area, but I think generally if we
can re-use intermediate shuffles, we should. Certainly, given the test
cases I have available, this seems like the right call.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229285 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-15 07:01:10 +00:00
Duncan P. N. Exon Smith
9de77c7eca CodeGen: Canonicalize access to function attributes, NFC
Canonicalize access to function attributes to use the simpler API.

getAttributes().getAttribute(AttributeSet::FunctionIndex, Kind)
  => getFnAttribute(Kind)

getAttributes().hasAttribute(AttributeSet::FunctionIndex, Kind)
  => hasFnAttribute(Kind)

Also, add `Function::getFnStackAlignment()`, and canonicalize:

getAttributes().getStackAlignment(AttributeSet::FunctionIndex)
  => getFnStackAlignment()

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229208 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-14 01:44:41 +00:00
Matthias Braun
821ec14add Revert "On ELF, put PIC jump tables in a non executable section."
This reverts commit r228939.

The commit broke something in the output of exception handling tables on
darwin x86-64.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229203 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-14 01:16:54 +00:00
Reid Kleckner
f7f5309424 Unify the two EH personality classification routines I wrote
We only need one.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229193 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-14 00:21:02 +00:00
Andrea Di Biagio
59d115311a [CodeGenPrepare] Removed duplicate logic. SimplifyCFG already knows how to speculate calls to cttz/ctlz.
SimplifyCFG now knows how to speculate calls to intrinsic cttz/ctlz that are
'cheap' for the target. Therefore, some of the logic in CodeGenPrepare
that was originally added at revision 224899 can now be removed.

This patch is basically a no functional change. It removes the duplicated
logic in CodeGenPrepare and converts all the existing target specific tests
for cttz/ctlz into SimplifyCFG tests.

Differential Revision: http://reviews.llvm.org/D7608


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229105 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-13 14:15:48 +00:00
Arnaud A. de Grandmaison
116347e269 [PBQP] Conservativelly allocatable nodes can be spilled and give a better solution
Although such nodes are allocatable, the cost of spilling may be less than
allocating to register, so spilling the node may provide a better solution.
The assert does not account for this case, so remove it for now.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229103 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-13 12:04:42 +00:00
Chandler Carruth
417c5c172c [PM] Remove the old 'PassManager.h' header file at the top level of
LLVM's include tree and the use of using declarations to hide the
'legacy' namespace for the old pass manager.

This undoes the primary modules-hostile change I made to keep
out-of-tree targets building. I sent an email inquiring about whether
this would be reasonable to do at this phase and people seemed fine with
it, so making it a reality. This should allow us to start bootstrapping
with modules to a certain extent along with making it easier to mix and
match headers in general.

The updates to any code for users of LLVM are very mechanical. Switch
from including "llvm/PassManager.h" to "llvm/IR/LegacyPassManager.h".
Qualify the types which now produce compile errors with "legacy::". The
most common ones are "PassManager", "PassManagerBase", and
"FunctionPassManager".

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229094 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-13 10:01:29 +00:00
Chandler Carruth
02d6288667 Re-sort #include lines using my handy dandy ./utils/sort_includes.py
script. This is in preparation for changes to lots of include lines.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229088 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-13 09:09:03 +00:00
Chandler Carruth
00ae03a747 Revert a series of commits starting at r228886 which is triggering some
regressions for LLDB on Linux. Rafael indicated on lldb-dev that we
should just go ahead and revert these but that he wasn't at a computer.
The patches backed out are as follows:

r228980: Add support for having multiple sections with the name and ...
r228889: Invert the section relocation map.
r228888: Use the existing SymbolTableIndex intsead of doing a lookup.
r228886: Create the Section -> Rel Section map when it is first needed.

These patches look pretty nice to me, so hoping its not too hard to get
them re-instated. =D

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229080 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-13 07:52:39 +00:00
Rafael Espindola
2fa06b171b Add support for having multiple sections with the same name and comdat.
Using this in combination with -ffunction-sections allows LLVM to output a .o
file with mulitple sections named .text. This saves space by avoiding long
unique names of the form .text.<C++ mangled name>.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228980 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-12 23:29:51 +00:00
Hal Finkel
8452d01224 [SDAG] Don't try to use FP_EXTEND/FP_ROUND for int<->fp promotions
The PowerPC backend has long promoted some floating-point vector operations
(such as select) to integer vector operations. Unfortunately, this behavior was
broken by r216555. When using FP_EXTEND/FP_ROUND for promotions, we must check
that both the old and new types are floating-point types. Otherwise, we must
use BITCAST as we did prior to r216555 for everything.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228969 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-12 22:43:52 +00:00
Rafael Espindola
c3c5d7c2d6 On ELF, put PIC jump tables in a non executable section.
Fixes PR22558.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228939 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-12 17:46:49 +00:00
Rafael Espindola
8eeedf74d3 Put each jump table in an independent section if the function is too.
This allows the linker to GC both, fixing pr22557.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228937 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-12 17:16:46 +00:00
Benjamin Kramer
d913d9d2c3 MathExtras: Bring Count(Trailing|Leading)Ones and CountPopulation in line with countTrailingZeros
Update all callers.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228930 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-12 15:35:40 +00:00
Ahmed Bougacha
9e9bde9b54 [CodeGen] Don't blindly combine (fp_round (fp_round x)) to (fp_round x).
We used to do this DAG combine, but it's not always correct:
If the first fp_round isn't a value preserving truncation, it might
introduce a tie in the second fp_round, that wouldn't occur in the
single-step fp_round we want to fold to.
In other words, double rounding isn't the same as rounding.

Differential Revision: http://reviews.llvm.org/D7571


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228911 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-12 06:15:29 +00:00
Jonas Paulsson
fc58cf7676 Fix SelectionDAG compile time issue with alias analysis.
Add new token factor node and its users to worklist if alias analysis is
turned on, in DAGCombiner::visitTokenFactor(). Alias analysis may cause
a lot of new token factors to be inserted into the DAG, and they need to
be optimized to avoid significant slow-downs.

Reviewed by Hal Finkel.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228841 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-11 16:10:31 +00:00
Rafael Espindola
831855275d Don't repeat name in comment and clang-format a function.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228831 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-11 14:44:17 +00:00
Arnaud A. de Grandmaison
8ee1b65836 [PBQP] Cautiously update edge costs in the solver
The NodeMetadata are maintained in an incremental way. When an edge between
2 nodes has its cost updated, in the course of graph reduction for example,
the NodeMetadata need first to have the old edge cost removed, then the new
edge cost added. Only once the NodeMetadata have been fully updated, it
becomes safe to consider promoting the nodes to the
ConservativelyAllocatable or OptimallyReducible sets. Previously, this
promotion was occuring right after the removing the old cost, and this was
breaking the assumption that a ConservativelyAllocatable should not be
spilled.

This patch also adds asserts to:
 - enforces the invariant that a node's reduction can not be downgraded,
 - only not provably allocatable or optimally reducible nodes can be spilled.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228816 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-11 08:25:36 +00:00
Zachary Turner
c371307e60 Use ADDITIONAL_HEADER_DIRS in all LLVM CMake projects.
This allows IDEs to recognize the entire set of header files for
each of the core LLVM projects.

Differential Revision: http://reviews.llvm.org/D7526
Reviewed By: Chris Bieneman

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228798 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-11 03:28:02 +00:00
Reid Kleckner
690248bf52 Don't promote asynch EH invokes of nounwind functions to calls
If the landingpad of the invoke is using a personality function that
catches asynch exceptions, then it can catch a trap.

Also add some landingpads to invalid LLVM IR test cases that lack them.

Over-the-shoulder reviewed by David Majnemer.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228782 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-11 01:23:16 +00:00
Petar Jovanovic
56e9c5f92b Fix makeLibCall argument (signed) in SoftenFloatRes_XINT_TO_FP function
The isSigned argument of makeLibCall function was hard-coded to false
(unsigned). This caused zero extension on MIPS64 soft float.
As the result SingleSource/Benchmarks/Stanford/FloatMM test and
SingleSource/UnitTests/2005-07-17-INT-To-FP test failed. 
The solution was to use the proper argument.

Patch by Strahinja Petrovic.

Differential Revision: http://reviews.llvm.org/D7292


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228765 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-10 23:30:14 +00:00
Adrian Prantl
7b98f2d2a6 Debug Info: Support variables that are described by more than one MMI
table entry. This happens when SROA splits up an alloca and the resulting
allocas cannot be lowered to SSA values because their address is passed
to a function.

Fixes PR22502.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228764 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-10 23:18:28 +00:00
Adrian Prantl
1e3e40b8c2 Fix indentation.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228763 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-10 23:18:15 +00:00
Andrew Kaylor
7741851819 Adding support for llvm.eh.begincatch and llvm.eh.endcatch intrinsics and beginning the documentation of native Windows exception handling.
Differential Revision: http://reviews.llvm.org/D7398



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228733 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-10 19:52:43 +00:00
Jonas Paulsson
b8ee890901 Two comment typo fixes in lib/CodeGen/SelectionDAG/DAGCombiner.cpp.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228700 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-10 15:34:29 +00:00
Jonas Paulsson
dacc4cf146 Bugfix for missed dependency from store to load in buildSchedGraph().
Background: When handling underlying objects for a store, the vector
of previous mem uses, mapped to the same Value, is afterwards cleared
(regardless of ThisMayAlias). This means that during handling of the
next store using the same Value, adjustChainDeps() must be called,
otherwise a dependency might be missed.

For example, three spill/reload (NonAliasing) memory accesses using
the same Value 'a', with different offsets:

    SU(2): store  @a
    SU(1): store  @a, Offset:1
    SU(0): load   @a

In this case we have:

* SU(1) does not need a dep against SU(0). Therefore,SU(0) ends up in
  RejectMemNodes and is removed from the mem-uses list (AliasMemUses
  or NonAliasMemUses), as this list is cleared.

* SU(2) needs a dep against SU(0). Therefore, SU(2) must check
  RejectMemNodes by calling adjustChainDeps().

Previously, for store SUs, adjustChainDeps() was only called if
MayAlias was true, missing the S(2) to S(0) dependency in the case
above. The fix is to always call adjustChainDeps(), regardless of
MayAlias, since this applies both for AliasMemUses and
NonAliasMemUses.

No testcase found for any in-tree target.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228686 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-10 13:03:32 +00:00
Chandler Carruth
1c7c2e8650 [x86] Fix PR22524: the DAG combiner was incorrectly handling illegal
nodes when folding bitcasts of constants.

We can't fold things and then check after-the-fact whether it was legal.
Once we have formed the DAG node, arbitrary other nodes may have been
collapsed to it. There is no easy way to go back. Instead, we need to
test for the specific folding cases we're interested in and ensure those
are legal first.

This could in theory make this less powerful for bitcasting from an
integer to some vector type, but AFAICT, that can't actually happen in
the SDAG so its fine. Now, we *only* whitelist specific int->fp and
fp->int bitcasts for post-legalization folding. I've added the test case
from the PR.

(Also as a note, this does not appear to be in 3.6, no backport needed)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228656 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-10 02:25:56 +00:00
Adrian Prantl
4f1b7f3100 Debug info: Use DW_OP_bit_piece instead of DW_OP_piece in the
intermediate representation. This
- increases consistency by using the same granularity everywhere
- allows for pieces < 1 byte
- DW_OP_piece didn't actually allow storing an offset.

Part of PR22495.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228631 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-09 23:57:15 +00:00
Duncan P. N. Exon Smith
99cc7e5307 DebugInfo: Remove DW_TAG_constant
Remove handling for DW_TAG_constant.  We started producing it in
r110656, but reverted that in r110876 without dropping the support.
Finish the job.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228623 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-09 22:48:04 +00:00
Benjamin Kramer
74cdff870f Move DebugLocs around instead of copying.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228491 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-07 12:28:15 +00:00
Bruce Mitchener
8143b4da3f Add more DWARF 5 language constants.
Differential Revision: http://reviews.llvm.org/D7430

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228487 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-07 06:35:30 +00:00
Quentin Colombet
4c2a2ac196 [LiveIntervalAnalysis] Speed up creation of live ranges for physical registers
by using a segment set.

The patch addresses a compile-time performance regression in the LiveIntervals
analysis pass (see http://llvm.org/bugs/show_bug.cgi?id=18580). This regression
is especially critical when compiling long functions. Our analysis had shown
that the most of time is taken for generation of live intervals for physical
registers. Insertions in the middle of the array of live ranges cause quadratic
algorithmic complexity, which is apparently the main reason for the slow-down. 

Overview of changes:
- The patch introduces an additional std::set<Segment>* member in LiveRange for
  storing segments in the phase of initial creation. The set is used if this
  member is not NULL, otherwise everything works the old way. 
- The set of operations on LiveRange used during initial creation (i.e. used by
  createDeadDefs and extendToUses) have been reimplemented to use the segment
  set if it is available.
- After a live range is created the contents of the set are flushed to the
  segment vector, because the set is not as efficient as the vector for the
  later uses of the live range. After the flushing, the set is deleted and
  cannot be used again.
- The set is only for live ranges computed in
  LiveIntervalAnalysis::computeLiveInRegUnits() and getRegUnit() but not in
  computeVirtRegs(), because I did not bring any performance benefits to
  computeVirtRegs() and for some examples even brought a slow down.

Patch by Vaidas Gasiunas <vaidas.gasiunas@sap.com>

Differential Revision: http://reviews.llvm.org/D6013


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228421 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-06 18:42:41 +00:00
Matthias Braun
e81cc348ac LiveInterval: Fix SubRange memory leak.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228405 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-06 17:28:47 +00:00
Arnaud A. de Grandmaison
52e57900a3 [PBQP] Fix comment wording. NFC
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228390 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-06 11:28:16 +00:00
Daniel Jasper
c7c2518a65 Small cleanup of MachineLICM.cpp
Specifically:
- Calculate the loop pre-header once at the stat of HoistOutOfLoop, so:
  - We don't-DFS walk the MachineDomTree if we aren't going to do anything
  - Don't call getCurPreheader for each Scope
- Don't needlessly use a do-while loop
- Use early exit for Scopes.size() == 0

No functional changes intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228350 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-05 22:39:46 +00:00
Ahmed Bougacha
ec35069525 [CodeGen] Add hook/combine to form vector extloads, enabled on X86.
The combine that forms extloads used to be disabled on vector types,
because "None of the supported targets knows how to perform load and
sign extend on vectors in one instruction."

That's not entirely true, since at least SSE4.1 X86 knows how to do
those sextloads/zextloads (with PMOVS/ZX).
But there are several aspects to getting this right.
First, vector extloads are controlled by a profitability callback.
For instance, on ARM, several instructions have folded extload forms,
so it's not always beneficial to create an extload node (and trying to
match extloads is a whole 'nother can of worms).

The interesting optimization enables folding of s/zextloads to illegal
(splittable) vector types, expanding them into smaller legal extloads.

It's not ideal (it introduces some legalization-like behavior in the
combine) but it's better than the obvious alternative: form illegal
extloads, and later try to split them up.  If you do that, you might
generate extloads that can't be split up, but have a valid ext+load
expansion.  At vector-op legalization time, it's too late to generate
this kind of code, so you end up forced to scalarize. It's better to
just avoid creating egregiously illegal nodes.

This optimization is enabled unconditionally on X86.

Note that the splitting combine is happy with "custom" extloads. As
is, this bypasses the actual custom lowering, and just unrolls the
extload. But from what I've seen, this is still much better than the
current custom lowering, which does some kind of unrolling at the end
anyway (see for instance load_sext_4i8_to_4i64 on SSE2, and the added
FIXME).

Also note that the existing combine that forms extloads is now also
enabled on legal vectors.  This doesn't have a big effect on X86
(because sext+load is usually combined to sext_inreg+aextload).
On ARM it fires on some rare occasions; that's for a separate commit.

Differential Revision: http://reviews.llvm.org/D6904


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228325 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-05 18:31:02 +00:00
Rafael Espindola
29b65fa1df Add a FIXME.
Thanks to Eric for the suggestion.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228300 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-05 14:57:47 +00:00
Rafael Espindola
e247dd2839 Don' try to make sections in comdats SHF_MERGE.
Parts of llvm were not expecting it and we wouldn't print
the entity size of the section.

Given what comdats are used for, having SHF_MERGE sections would be
just a small improvement, so just disable it for now.

Fixes pr22463.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228196 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-04 21:27:24 +00:00
Matthias Braun
a602c10686 MachineCSE: Clear dead-def flag on CSE.
In case CSE reuses a previoulsy unused register the dead-def flag has to
be cleared on the def operand, as exposed by the arm64-cse.ll test.

This fixes PR22439 and the corresponding rdar://19694987

Differential Revision: http://reviews.llvm.org/D7395

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228178 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-04 19:35:16 +00:00
Michael Kuperstein
8f260e3084 Fixes a bug in vector load legalization that confused bits and bytes.
Differential Revision: http://reviews.llvm.org/D7400

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228168 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-04 18:54:01 +00:00