The static analyzer is warning about potential null dereferences of dyn_cast<> results, we can use cast<> directly as we know that these cases should all be CastInst, which is why its working atm and anyway cast<> will assert if they aren't.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@372116 91177308-0d34-0410-b5e6-96231b3b80d8
The static analyzer is warning about a potential null dereference of the cast_or_null result, I've split the cast_or_null check from the ->getUnderlyingInstr() call to avoid this, but it appears that we weren't seeing any null pointers in the dumped bundles in the first place.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@371975 91177308-0d34-0410-b5e6-96231b3b80d8
The static analyzer is warning about potential null dereferences of dyn_cast<> results - in these cases we can safely use cast<> directly as we know that these cases should all be the correct type, which is why its working atm and anyway cast<> will assert if they aren't.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@371973 91177308-0d34-0410-b5e6-96231b3b80d8
Silence static analyzer uninitialized variable warning by setting the LoadTy to null and then asserting we find a real value.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@371936 91177308-0d34-0410-b5e6-96231b3b80d8
This is a fix for:
https://bugs.llvm.org/show_bug.cgi?id=33958
It seems universally true that we would not want to transform this kind of
sequence on any target, but if that's not correct, then we could view this
as a target-specific cost model problem. We could also white-list ConstantInt,
ConstantFP, etc. rather than blacklist Global and ConstantExpr.
Differential Revision: https://reviews.llvm.org/D67362
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@371931 91177308-0d34-0410-b5e6-96231b3b80d8
Expose a utility function so that all places which want to suppress speculation (when otherwise legal) due to ordering and/or sanitizer interaction can do so.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@371556 91177308-0d34-0410-b5e6-96231b3b80d8
If we're vectorizing a load in a predicated block, check to see if the load can be speculated rather than predicated. This allows us to generate a normal vector load instead of a masked.load.
To do so, we must prove that all bytes accessed on any iteration of the original loop are dereferenceable, and that all loads (across all iterations) are properly aligned. This is equivelent to proving that hoisting the load into the loop header in the original scalar loop is safe.
Note: There are a couple of code motion todos in the code. My intention is to wait about a day - to be sure this sticks - and then perform the NFC motion without furthe review.
Differential Revision: https://reviews.llvm.org/D66688
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@371452 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This is the first change to enable the TLI to be built per-function so
that -fno-builtin* handling can be migrated to use function attributes.
See discussion on D61634 for background. This is an enabler for fixing
handling of these options for LTO, for example.
This change should not affect behavior, as the provided function is not
yet used to build a specifically per-function TLI, but rather enables
that migration.
Most of the changes were very mechanical, e.g. passing a Function to the
legacy analysis pass's getTLI interface, or in Module level cases,
adding a callback. This is similar to the way the per-function TTI
analysis works.
There was one place where we were looking for builtins but not in the
context of a specific function. See FindCXAAtExit in
lib/Transforms/IPO/GlobalOpt.cpp. I'm somewhat concerned my workaround
could provide the wrong behavior in some corner cases. Suggestions
welcome.
Reviewers: chandlerc, hfinkel
Subscribers: arsenm, dschuff, jvesely, nhaehnle, mehdi_amini, javed.absar, sbc100, jgravelle-google, eraman, aheejin, steven_wu, george.burgess.iv, dexonsmith, jfb, asbirlea, gchatelet, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D66428
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@371284 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Fold-tail currently supports reduction last-vector-value live-out's,
but has yet to support last-scalar-value live-outs, including
non-header phi's. As it relies on AllowedExit in order to detect
them and bail out we need to add the non-header PHI nodes to
AllowedExit, otherwise we end up with miscompiles.
Solves https://bugs.llvm.org/show_bug.cgi?id=43166
Reviewers: fhahn, Ayal
Reviewed By: fhahn, Ayal
Subscribers: anna, hiraditya, rkruppe, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D67074
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@370721 91177308-0d34-0410-b5e6-96231b3b80d8
Allow vectorizing loops that have reductions when tail is folded by masking.
A select is introduced in VPlan, choosing between the last value carried by the
loop-exit/live-out instruction of the reduction, and the penultimate value
carried by the reduction phi, according to the "i < n" mask of fold-tail.
This select replaces the last value as the live-out value of the loop.
Differential Revision: https://reviews.llvm.org/D66720
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@370173 91177308-0d34-0410-b5e6-96231b3b80d8
These are part of D57059, but that patch doesn't apply cleanly to trunk
at this point, so we might as well remove some of the noise.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@369776 91177308-0d34-0410-b5e6-96231b3b80d8
These are part of D57059, but that patch doesn't apply cleanly to trunk
at this point, so we might as well remove some of the noise.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@369769 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
The scheduler's dependence graph gets the use-def dependencies by accessing the operands of the instructions in a bundle. However, buildTree_rec() may change the order of the operands in TreeEntry, and the scheduler is currently not aware of this. This is not causing any functional issues currently, because reordering is restricted to the operands of a single instruction. Once we support operand reordering across multiple TreeEntries, as shown here: http://www.llvm.org/devmtg/2019-04/slides/Poster-Porpodas-Supernode_SLP.pdf , the scheduler will need to get the correct operands from TreeEntry and not from the individual instructions.
In short, this patch:
- Connects the scheduler's bundle with the corresponding TreeEntry. It introduces new TE and Lane fields in ScheduleData.
- Moves the location where the operands of the TreeEntry are initialized. This used to take place in newTreeEntry() setting one operand at a time, but is now moved pre-order just before the recursion of buildTree_rec(). This is required because the scheduler needs to access both operands of the TreeEntry in tryScheduleBundle().
- Updates the scheduler to access the instruction operands through the TreeEntry operands instead of accessing the instruction operands directly.
Reviewers: ABataev, RKSimon, dtemirbulatov, Ayal, dorit, hfinkel
Reviewed By: ABataev
Subscribers: hiraditya, llvm-commits, lebedev.ri, rcorcs
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D62432
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@369131 91177308-0d34-0410-b5e6-96231b3b80d8
cppcheck + MSVC analyzer both over zealously warn that we might dereference a null Bundle pointer - add an assertion to check for null to silence the warning, plus its a good idea to check that we succeeded in finding a schedule bundle anyway....
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@369094 91177308-0d34-0410-b5e6-96231b3b80d8
Now that we've moved to C++14, we no longer need the llvm::make_unique
implementation from STLExtras.h. This patch is a mechanical replacement
of (hopefully) all the llvm::make_unique instances across the monorepo.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@369013 91177308-0d34-0410-b5e6-96231b3b80d8
assume_safety implies that loads under "if's" can be safely executed
speculatively (unguarded, unmasked). However this assumption holds only for the
original user "if's", not those introduced by the compiler, such as the
fold-tail "if" that guards us from loading beyond the original loop trip-count.
Currently the combination of fold-tail and assume-safety pragmas results in
ignoring the fold-tail predicate that guards the loads, generating unmasked
loads. This patch fixes this behavior.
Differential Revision: https://reviews.llvm.org/D66106
Reviewers: Ayal, hsaito, fhahn
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@368973 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts commit fc33e33776b7a7ce22e539f0ec2e3bfdb09ad361.
This commit depends on the rolled back commit rL367901, and thus needs
to be rolled back.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@368109 91177308-0d34-0410-b5e6-96231b3b80d8
With the switch to widening legalization, we need to a better
job of costing extractions of less than 128-bits.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@368081 91177308-0d34-0410-b5e6-96231b3b80d8
The previous change to fix crash in the vectorizer introduced
performance regressions. The condition to preserve pointer
address space during the search is too tight, we only need to
match the size.
Differential Revision: https://reviews.llvm.org/D65600
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@367624 91177308-0d34-0410-b5e6-96231b3b80d8
This allows folding of the scalar epilogue loop (the tail) into the main
vectorised loop body when the loop is annotated with a "vector predicate"
metadata hint. To fold the tail, instructions need to be predicated (masked),
enabling/disabling lanes for the remainder iterations.
Differential Revision: https://reviews.llvm.org/D65197
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@367592 91177308-0d34-0410-b5e6-96231b3b80d8
This refactors boolean 'OptForSize' that was passed around in a lot of places.
It controlled folding of the tail loop, the scalar epilogue, into the main loop
but code-size reasons may not be the only reason to do this. Thus, this is a
first step to generalise the concept of tail-loop folding, and hence OptForSize
has been renamed and is using an enum ScalarEpilogueStatus that holds the
status how the epilogue should be lowered.
This will be followed up by D65197, that picks up the predicate loop hint and
performs the tail-loop folding.
Differential Revision: https://reviews.llvm.org/D64916
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@366993 91177308-0d34-0410-b5e6-96231b3b80d8
This patch introduces the DAG version of SimplifyMultipleUseDemandedBits, which attempts to peek through ops (mainly and/or/xor so far) that don't contribute to the demandedbits/elts of a node - which means we can do this even in cases where we have multiple uses of an op, which normally requires us to demanded all bits/elts. The intention is to remove a similar instruction - SelectionDAG::GetDemandedBits - once SimplifyMultipleUseDemandedBits has matured.
The InstCombine version of SimplifyMultipleUseDemandedBits can constant fold which I haven't added here yet, and so far I've only wired this up to some basic binops (and/or/xor/add/sub/mul) to demonstrate its use.
We do see a couple of regressions that need to be addressed:
AMDGPU unsigned dot product codegen retains an AND mask (for ZERO_EXTEND) that it previously removed (but otherwise the dotproduct codegen is a lot better).
X86/AVX2 has poor handling of vector ANY_EXTEND/ANY_EXTEND_VECTOR_INREG - it prematurely gets converted to ZERO_EXTEND_VECTOR_INREG.
The code owners have confirmed its ok for these cases to fixed up in future patches.
Differential Revision: https://reviews.llvm.org/D63281
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@366799 91177308-0d34-0410-b5e6-96231b3b80d8
cast<CallInst> shouldn't return null and we dereference the pointer in a lot of other places, causing both MSVC + cppcheck to warn about dereferenced null pointers
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@366793 91177308-0d34-0410-b5e6-96231b3b80d8
As there are some reported miscompiles with AVX512 and performance regressions
in Eigen. Verified with the original committer and testcases will be forthcoming.
This reverts commit r364964.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@366154 91177308-0d34-0410-b5e6-96231b3b80d8
We do not compute the scalarization overhead in getVectorIntrinsicCost
and TTI::getIntrinsicInstrCost requires the full arguments list.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@366049 91177308-0d34-0410-b5e6-96231b3b80d8
Loop invariant operands do not need to be scalarized, as we are using
the values outside the loop. We should ignore them when computing the
scalarization overhead.
Fixes PR41294
Reviewers: hsaito, rengolin, dcaballe, Ayal
Reviewed By: Ayal
Differential Revision: https://reviews.llvm.org/D59995
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@366030 91177308-0d34-0410-b5e6-96231b3b80d8
For a given set of live values, the spill cost will always be the
same for each call. Compute the cost once and multiply it by the
number of calls.
(I'm not sure this spill cost modeling makes sense if there are
multiple calls, as the spill cost will likely be shared across
calls in that case. But that's how it currently works.)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@365552 91177308-0d34-0410-b5e6-96231b3b80d8
Summary: This patch introduces a new heuristic for guiding operand reordering. The new "look-ahead" heuristic can look beyond the immediate predecessors. This helps break ties when the immediate predecessors have identical opcodes (see lit test for an example).
Reviewers: RKSimon, ABataev, dtemirbulatov, Ayal, hfinkel, rnk
Reviewed By: RKSimon, dtemirbulatov
Subscribers: hiraditya, phosek, rnk, rcorcs, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D60897
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@364964 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts r364478 (git commit 574cb0eb3a7ac95e62d223a60bef891171dfe321)
The patch is causing compilation timeouts.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@364846 91177308-0d34-0410-b5e6-96231b3b80d8
