6801 Commits

Author SHA1 Message Date
Mehdi Amini
8d25e3a832 Fixup for recent -fast-isel-abort change: code didn't match description
Level 1 should abort for all instructions but call/terminators/args.
Instead it was aborting only if the level was > 2

From: Mehdi Amini <mehdi.amini@apple.com>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230861 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-28 19:34:54 +00:00
Benjamin Kramer
bac8d0ec70 Convert push_back loops into append calls.
No functionality change intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230849 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-28 13:20:15 +00:00
Benjamin Kramer
9f9dcf8046 Reduce double set lookups.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230798 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-27 21:43:14 +00:00
Mehdi Amini
26d628d6ce Change the fast-isel-abort option from bool to int to enable "levels"
Summary:
Currently fast-isel-abort will only abort for regular instructions,
and just warn for function calls, terminators, function arguments.
There is already fast-isel-abort-args but nothing for calls and
terminators.

This change turns the fast-isel-abort options into an integer option,
so that multiple levels of strictness can be defined.
This will help no being surprised when the "abort" option indeed does
not abort, and enables the possibility to write test that verifies
that no intrinsics are forgotten by fast-isel.

Reviewers: resistor, echristo

Subscribers: jfb, llvm-commits

Differential Revision: http://reviews.llvm.org/D7941

From: Mehdi Amini <mehdi.amini@apple.com>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230775 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-27 18:32:11 +00:00
Eric Christopher
acdd4442cb getRegForInlineAsmConstraint wants to use TargetRegisterInfo for
a lookup, pass that in rather than use a naked call to getSubtargetImpl.
This involved passing down and around either a TargetMachine or
TargetRegisterInfo. Update all callers/definitions around the targets
and SelectionDAG.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230699 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-26 22:38:43 +00:00
Paul Robinson
b2f521b647 When the source has a series of assignments, users reasonably want to
have the debugger step through each one individually. Turn off the
combine for adjacent stores at -O0 so we get this behavior.

Possibly, DAGCombine shouldn't run at all at -O0, but that's for
another day; see PR22346.

Differential Revision: http://reviews.llvm.org/D7181


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230659 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-26 18:47:57 +00:00
Simon Pilgrim
41cda40157 Reapplied D7816 & rL230177 & rL230278 - with an additional fix toensure that the smallest build vector input scalar type is always used. Additional (crash) test cases already committed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230388 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-24 22:08:56 +00:00
Eric Christopher
7c611d59cc Revert:
Author: Simon Pilgrim <llvm-dev@redking.me.uk>
Date:   Mon Feb 23 23:04:28 2015 +0000

    Fix based on post-commit comment on D7816 & rL230177 - BUILD_VECTOR operand truncation was using the the BV's output scalar type instead of the input type.

and

Author: Simon Pilgrim <llvm-dev@redking.me.uk>
Date:   Sun Feb 22 18:17:28 2015 +0000

    [DagCombiner] Generalized BuildVector Vector Concatenation

    The CONCAT_VECTORS combiner pass can transform the concat of two BUILD_VECTOR nodes into a single BUILD_VECTOR node.

    This patch generalises this to support any number of BUILD_VECTOR nodes, and also permits UNDEF nodes to be included as well.

    This was noticed as AVX vec128 -> vec256 canonicalization sometimes creates a CONCAT_VECTOR with a real vec128 lower and an vec128 UNDEF upper.

    Differential Revision: http://reviews.llvm.org/D7816

as the root cause of PR22678 which is causing an assertion inside the DAG combiner.

I'll follow up to the main thread as well.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230358 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-24 19:11:00 +00:00
Matthias Braun
8b1add3c13 DAGCombiner: Move variable definitions closer to use; NFC
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230354 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-24 18:52:01 +00:00
Matthias Braun
5f146de042 DAGCombiner: Move variable declaration closer to definiion; NFC
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230353 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-24 18:51:59 +00:00
Tim Northover
5530ac99e6 ARM: treat [N x i32] and [N x i64] as AAPCS composite types
The logic is almost there already, with our special homogeneous aggregate
handling. Tweaking it like this allows front-ends to emit AAPCS compliant code
without ever having to count registers or add discarded padding arguments.

Only arrays of i32 and i64 are needed to model AAPCS rules, but I decided to
apply the logic to all integer arrays for more consistency.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230348 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-24 17:22:34 +00:00
Hal Finkel
cccfe54933 [SDAG] Handle LowerOperation returning its input consistently
For almost all node types, if the target requested custom lowering, and
LowerOperation returned its input, we'd treat the original node as legal. This
did not work, however, for many loads and stores, because they follow
slightly different code paths, and we did not account for the possibility of
LowerOperation returning its input at those call sites.

I think that we now handle this consistently everywhere. At the call sites in
LegalizeDAG, we used to assert in this case, so there's no functional change
for any existing code there. For the call sites in LegalizeVectorOps, this
really only affects whether or not we set Changed = true, but I think makes the
semantics clearer.

No test case here, but it will be covered by an upcoming PowerPC commit adding
QPX support.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230332 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-24 12:59:47 +00:00
Simon Pilgrim
a631cd85ca Fix based on post-commit comment on D7816 & rL230177 - BUILD_VECTOR operand truncation was using the the BV's output scalar type instead of the input type.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230278 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-23 23:04:28 +00:00
Andrea Di Biagio
770e106ed6 [X86] Teach how to custom lower double-to-half conversions under fast-math.
This patch teaches the backend how to expand a double-half conversion into
a double-float conversion immediately followed by a float-half conversion.
We do this only under fast-math, and if float-half conversions are legal
for the target.

Added test CodeGen/X86/fastmath-float-half-conversion.ll

Differential Revision: http://reviews.llvm.org/D7832


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230276 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-23 22:59:02 +00:00
Simon Pilgrim
66c960350c [DagCombiner] Generalized BuildVector Vector Concatenation
The CONCAT_VECTORS combiner pass can transform the concat of two BUILD_VECTOR nodes into a single BUILD_VECTOR node.

This patch generalises this to support any number of BUILD_VECTOR nodes, and also permits UNDEF nodes to be included as well.

This was noticed as AVX vec128 -> vec256 canonicalization sometimes creates a CONCAT_VECTOR with a real vec128 lower and an vec128 UNDEF upper.

Differential Revision: http://reviews.llvm.org/D7816

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230177 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-22 18:17:28 +00:00
Hal Finkel
0e8abfa6ed [DAGCombine] Don't assume integer-type legailty in reduceBuildVecConvertToConvertBuildVec
DAGCombine will rewrite an BUILD_VECTOR where all non-undef inputs some from
[US]INT_TO_FP, as a BUILD_VECTOR of integers with the conversion applied as a
vector operation. We check operation legality of the conversion, but fail to
check legality of the integer vector type itself. Because targets don't
normally override operation legality defaults for illegal types, we need to
check this also.

This came up in the context of the QPX vector entensions for PowerPC (which can
have legal floating-point vector types without corresponding legal integer
vector types). No in-tree test case for this yes, but one can be added once
the QPX support has been committed.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230176 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-22 16:10:22 +00:00
Hal Finkel
1584f114c1 [SDAG] Use correct alignments on expanded vector trunc-store/ext-loads
When expanding a truncating store or extending load using vector extracts or
inserts and scalar stores and loads, we were giving each of these scalar stores
or loads the same alignment as the original vector operation. While this will
often be right (most vector operations, especially those produced by
autovectorization, have the alignment of the underlying scalar type), the
vector operation could certainly have a larger alignment.

No test case (yet); noticed by inspection.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230175 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-22 15:58:04 +00:00
David Majnemer
164db1c6b9 X86: Call __main using the SelectionDAG
Synthesizing a call directly using the MI layer would confuse the frame
lowering code.  This is problematic as frame lowering is highly
sensitive the particularities of calls, etc.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230129 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-21 05:49:45 +00:00
Matt Arsenault
4bacfe2095 Add generic fmad DAG node.
This allows sharing of FMA forming combines to work
with instructions that have the same semantics as a separate
multiply and add.

This is expand by default, and only formed post legalization
so it shouldn't have much impact on targets that do not want it.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230070 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-20 22:10:33 +00:00
Igor Laevsky
45c732502e Generalize statepoint lowering to use ImmutableStatepoint. Move statepoint lowering into a separate function 'LowerStatepoint' which uses ImmutableStatepoint instead of a CallInst. Also related utility functions are changed to receive ImmutableCallSite.
Differential Revision: http://reviews.llvm.org/D7756 



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230017 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-20 15:28:35 +00:00
Ahmed Bougacha
953c5c9458 [CodeGen] Use ArrayRef instead of std::vector&. NFC.
The former lets us use SmallVectors.  Do so in ARM and AArch64.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229925 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-19 23:13:10 +00:00
Benjamin Kramer
1ce666d86c Demote vectors to arrays. No functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229861 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-19 15:26:17 +00:00
Chandler Carruth
a8fb39af83 [x86,sdag] Two interrelated changes to the x86 and sdag code.
First, don't combine bit masking into vector shuffles (even ones the
target can handle) once operation legalization has taken place. Custom
legalization of vector shuffles may exist for these patterns (making the
predicate return true) but that custom legalization may in some cases
produce the exact bit math this matches. We only really want to handle
this prior to operation legalization.

However, the x86 backend, in a fit of awesome, relied on this. What it
would do is mark VSELECTs as expand, which would turn them into
arithmetic, which this would then match back into vector shuffles, which
we would then lower properly. Amazing.

Instead, the second change is to teach the x86 backend to directly form
vector shuffles from VSELECT nodes with constant conditions, and to mark
all of the vector types we support lowering blends as shuffles as custom
VSELECT lowering. We still mark the forms which actually support
variable blends as *legal* so that the custom lowering is bypassed, and
the legal lowering can even be used by the vector shuffle legalization
(yes, i know, this is confusing. but that's how the patterns are
written).

This makes the VSELECT lowering much more sensible, and in fact should
fix a bunch of bugs with it. However, as you'll see in the test cases,
right now what it does is point out the *hilarious* deficiency of the
new vector shuffle lowering when it comes to blends. Fortunately, my
very next patch fixes that. I can't submit it yet, because that patch,
somewhat obviously, forms the exact and/or pattern that the DAG combine
is matching here! Without this patch, teaching the vector shuffle
lowering to produce the right code infloops in the DAG combiner. With
this patch alone, we produce terrible code but at least lower through
the right paths. With both patches, all the regressions here should be
fixed, and a bunch of the improvements (like using 2 shufps with no
memory loads instead of 2 andps with memory loads and an orps) will
stay. Win!

There is one other change worth noting here. We had hilariously wrong
vectorization cost estimates for vselect because we fell through to the
code path that assumed all "expand" vector operations are scalarized.
However, the "expand" lowering of VSELECT is vector bit math, most
definitely not scalarized. So now we go back to the correct if horribly
naive cost of "1" for "not scalarized". If anyone wants to add actual
modeling of shuffle costs, that would be cool, but this seems an
improvement on its own. Note the removal of 16 and 32 "costs" for doing
a blend. Even in SSE2 we can blend in fewer than 16 instructions. ;] Of
course, we don't right now because of OMG bad code, but I'm going to fix
that. Next patch. I promise.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229835 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-19 10:36:19 +00:00
Michael Kuperstein
9571ea6620 Fixes two issue in SimplifyDemandedBits of sext_in_reg:
1) We should not try to simplify if the sext has multiple uses
2) There is no need to simplify is the source value is already sign-extended.

Patch by Gil Rapaport <gil.rapaport@intel.com>

Differential Revision: http://reviews.llvm.org/D6949

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229659 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-18 09:43:40 +00:00
Sanjay Patel
1115b2c27e Canonicalize splats as build_vectors (PR22283)
This is a follow-on patch to:
http://reviews.llvm.org/D7093

That patch canonicalized constant splats as build_vectors, 
and this patch removes the constant check so we can canonicalize
all splats as build_vectors.

This fixes the 2nd test case in PR22283:
http://llvm.org/bugs/show_bug.cgi?id=22283

The unfortunate code duplication between SelectionDAG and DAGCombiner
is discussed in the earlier patch review. At least this patch is just
removing code...

This improves an existing x86 AVX test and changes codegen in an ARM test.

Differential Revision: http://reviews.llvm.org/D7389


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229511 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-17 16:54:32 +00:00
Benjamin Kramer
1a50a12b43 Prefer SmallVector::append/insert over push_back loops.
Same functionality, but hoists the vector growth out of the loop.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229500 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-17 15:29:18 +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
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
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
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
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
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
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
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
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
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
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
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
Manuel Jacob
c8d6db0fc0 Add nullptr checks for TargetSelectionDAGInfo in SelectionDAG.
TSI is not guaranteed be non-null in SelectionDAG.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227397 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-28 23:50:40 +00:00
Quentin Colombet
24508d33fb Revert r227242 - Merge vector stores into wider vector stores (PR21711).
This commit creates infinite loop in DAG combine for in the LLVM test-suite
for aarch64 with mcpu=cylcone (just having neon may be enough to expose this).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227272 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-27 23:58:01 +00:00
Sanjay Patel
c94f9d3d2f Merge vector stores into wider vector stores (PR21711)
This patch resolves part of PR21711 ( http://llvm.org/bugs/show_bug.cgi?id=21711 ).

The 'f3' test case in that report presents a situation where we have two 128-bit
stores extracted from a 256-bit source vector. 

Instead of producing this:

vmovaps %xmm0, (%rdi)
vextractf128    $1, %ymm0, 16(%rdi)

This patch merges the 128-bit stores into a single 256-bit store:

vmovups %ymm0, (%rdi)

Differential Revision: http://reviews.llvm.org/D7208



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227242 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-27 20:50:27 +00:00
Manuel Jacob
145de00800 Add a FIXME in SelectionDAGBuilder before an assert that is valid only on X86.
When lowering memcpy, memset or memmove, this assert checks whether the pointer
operands are in an address space < 256 which means "user defined address space"
on X86.  However, this notion of "user defined address space" does not exist
for other targets.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227191 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-27 13:14:35 +00:00
Eric Christopher
cdafa1003b Grab the TargetLowering info from the DAG rather than querying for
a subtarget.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227156 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-27 01:01:36 +00:00
Ahmed Bougacha
6f9c8fa5d4 [SelectionDAG] Fix assert message copypasta. NFC.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227119 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-26 19:31:42 +00:00
Eric Christopher
04bcc11905 Move DataLayout back to the TargetMachine from TargetSubtargetInfo
derived classes.

Since global data alignment, layout, and mangling is often based on the
DataLayout, move it to the TargetMachine. This ensures that global
data is going to be layed out and mangled consistently if the subtarget
changes on a per function basis. Prior to this all targets(*) have
had subtarget dependent code moved out and onto the TargetMachine.

*One target hasn't been migrated as part of this change: R600. The
R600 port has, as a subtarget feature, the size of pointers and
this affects global data layout. I've currently hacked in a FIXME
to enable progress, but the port needs to be updated to either pass
the 64-bitness to the TargetMachine, or fix the DataLayout to
avoid subtarget dependent features.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227113 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-26 19:03:15 +00:00