22770 Commits

Author SHA1 Message Date
Craig Topper
6749dc3446 [InstCombine] Don't transform bitcasts between x86_mmx and v1i64 into insertelement/extractelement
x86_mmx is conceptually a vector already. Don't introduce an extra conversion between it and scalar i64.

I'm using VectorType::isValidElementType which checks for floating point, integer, and pointers to hopefully make this more readable than just blacklisting x86_mmx.

Differential Revision: https://reviews.llvm.org/D69964
2019-11-07 15:14:13 -08:00
Daniel Sanders
25ee861372 [debugify] Move the Debugify pass from tools/opt to lib/Transform/Utils
Summary:
I need to make use of this pass from a driver program that isn't opt.
Therefore this patch moves this pass into the LLVM library so that it is
available for use elsewhere.

There was one function I kept in tools/opt which is exportDebugifyStats()
this is because it's serializing the statistics into a human readable
format and this seemed more in keeping with opt than a library function

Reviewers: vsk, aprantl

Subscribers: mgorny, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69926
2019-11-07 14:41:54 -08:00
Vedant Kumar
a087b78bc4 Wrong debug info generated at -O2 (-O0 is correct)
Instcombiner pass was erasing trivially dead instruction without updating dependent llvm.dbg.value.
which was not showing programmer current state of variables while debugging.
As a part of this fix I did following,
Iterate throught all the users (llvm.dbg) of a instruction which is trivially dead and set each if them undef, Before deleting the instruction.
Now user will see optimized out, when try to print those variables.
This fixes
https://bugs.llvm.org/show_bug.cgi?id=43893

This is my first fix to llvm.

Patch by kamlesh kumar!

Differential Revision: https://reviews.llvm.org/D69809
2019-11-07 11:19:41 -08:00
Sanjay Patel
d9ccb6367a [InstCombine] canonicalize shift+logic+shift to reduce dependency chain
shift (logic (shift X, C0), Y), C1 --> logic (shift X, C0+C1), (shift Y, C1)

This is an IR translation of an existing SDAG transform added here:
rL370617

So we again have 9 possible patterns with a commuted IR variant of each pattern:
https://rise4fun.com/Alive/VlI
https://rise4fun.com/Alive/n1m
https://rise4fun.com/Alive/1Vn

Part of the motivation is to allow easier recognition and subsequent
canonicalization of bswap patterns as discussed in PR43146:
https://bugs.llvm.org/show_bug.cgi?id=43146

We had to delay this transform because it used to allow the SLP vectorizer
to create awful reductions out of simple load-combines.
That problem was fixed with:
rL375025
(we'll bring back load combining in IR someday...)

The backend is also better equipped to deal with these patterns now
using hooks like TLI.getShiftAmountThreshold().

The only remaining potential controversy is that the -reassociate pass
tends to reverse this kind of pattern (to help GVN?). But since -reassociate
doesn't do anything with these specific patterns, there is no conflict currently.

Finally, there's a new pass proposal at D67383 for general tree-height-reduction
reassociation, and it could use a cost model to decide how to optimally rearrange
these kinds of ops for a target. That patch appears to be stalled.

Differential Revision: https://reviews.llvm.org/D69842
2019-11-07 12:09:45 -05:00
evgeny
dde589389f [ThinLTO] Import readonly vars with refs
Patch allows importing declarations of functions and variables, referenced
by the initializer of some other readonly variable.
Differential revision: https://reviews.llvm.org/D69561
2019-11-07 15:13:35 +03:00
Sanjay Patel
7ff57705ba [SLP] allow forming 2-way reduction patterns
We have a vector compare reduction problem seen in PR39665 comment 2:
https://bugs.llvm.org/show_bug.cgi?id=39665#c2

Or slightly reduced here:

define i1 @cmp2(<2 x double> %a0) {
  %a = fcmp ogt <2 x double> %a0, <double 1.0, double 1.0>
  %b = extractelement <2 x i1> %a, i32 0
  %c = extractelement <2 x i1> %a, i32 1
  %d = and i1 %b, %c
  ret i1 %d
}

SLP would not attempt to turn this into a vector reduction because there is an
artificial lower limit on that transform. We can not completely remove that limit
without inducing regressions though, so this patch just hacks an extra attempt at
creating a 2-way reduction to the end of the analysis.

As shown in the test file, we are still not getting some of the motivating cases,
so follow-on patches will be needed to solve those cases.

Differential Revision: https://reviews.llvm.org/D59710
2019-11-07 06:08:42 -05:00
Eric Christopher
009e032634 Temporarily Revert "[LV] Apply sink-after & interleave-groups as VPlan transformations (NFC)"
as it's causing assert failures.

This reverts commit 100e797adb433724a17c9b42b6533cd634cb796b.
2019-11-06 21:58:28 -08:00
Wenlei He
ba1dfae054 Keep import function list for inlinee profile update
Summary:
When adjusting function entry counts after inlining, Funciton::setEntryCount is called without providing an import function list. The side effect of that is the previously set import function list will be dropped. The import function list is used by ThinLTO to help import hot cross module callee for LTO inlining, so dropping that during ThinLTO pre-link may adversely affect LTO inlining. The fix is to keep the list while updating entry counts for inlining.

Reviewers: wmi, davidxl, tejohnson

Subscribers: mehdi_amini, hiraditya, dexonsmith, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69736
2019-11-06 18:36:00 -08:00
Eric Christopher
e511c4b0df Temporarily Revert:
"[SLP] Generalization of stores vectorization."
 "[SLP] Fix -Wunused-variable. NFC"
 "[SLP] Vectorize jumbled stores."

As they're causing significant (10-30x) compile time regressions on
vectorizable code.

The primary cause of the compile-time regression is f228b5371647f471853c5fb3e6719823a42fe451.

This reverts commits:

f228b5371647f471853c5fb3e6719823a42fe451
5503455ccb3f5fcedced158332c016c8d3a7fa81
21d498c9c0f32dcab5bc89ac593aa813b533b43a
2019-11-06 16:06:15 -08:00
Philip Reames
8748be7750 [LoopPred] Enable new transformation by default
The basic idea of the transform is to convert variant loop exit conditions into invariant exit conditions by changing the iteration on which the exit is taken when we know that the trip count is unobservable.  See the original patch which introduced the code for a more complete explanation.

The individual parts of this have been reviewed, the result has been fuzzed, and then further analyzed by hand, but despite all of that, I will not be suprised to see breakage here.  If you see problems, please don't hesitate to revert - though please do provide a test case.  The most likely class of issues are latent SCEV bugs and without a reduced test case, I'll be essentially stuck on reducing them.

(Note: A bunch of tests were opted out of the new transform to preserve coverage.  That landed in a previous commit to simplify revert cycles if they turn out to be needed.)
2019-11-06 15:41:57 -08:00
Kazu Hirata
f0f73ed8b0 [JumpThreading] Factor out code to clone instructions (NFC)
Summary:
This patch factors out code to clone instructions -- partly for
readability and partly to facilitate an upcoming patch of my own.

Reviewers: wmi

Subscribers: hiraditya, jfb, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69861
2019-11-06 14:16:48 -08:00
Philip Reames
686f449e3d [WC] Fix a subtle bug in our definition of widenable branch
We had a subtle, but nasty bug in our definition of a widenable branch, and thus in the transforms which used that utility. Specifically, we returned true for any branch which included a widenable condition within it's condition, regardless of whether that widenable condition also had other uses.

The problem is that the result of the WC() call is defined to be one particular value. As such, all users must agree as to what that value is. If we widen a branch without also updating *all other users* of the WC in the same way, we have broken the required semantics.

Most of the textual diff is updating existing transforms not to leave dead uses hanging around. They're largely NFC as the dead instructions would be immediately deleted by other passes. The reason to make these changes is so that the transforms preserve the widenable branch form.

In practice, we don't get bitten by this only because it isn't profitable to CSE WC() calls and the lowering pass from guards uses distinct WC calls per branch.

Differential Revision: https://reviews.llvm.org/D69916
2019-11-06 14:16:34 -08:00
Philip Reames
9bfa5ab3d1 [LoopPred] Fix two subtle issues found by inspection
This patch fixes two issues noticed by inspection when going to enable the loop predication code in IndVarSimplify.

Issue 1 - Both the LoopPredication transform, and the already on by default optimizeLoopExits transform, modify the exit count of the exits they modify. (either to 0 or Infinity) Looking at the code more closely, this was not reflected into SCEV and we were instead running later transforms with incorrect SCEVs. Fixing this requires forgetting the loop, weakening a too strong assert, and updating SCEV to not pessimize results when a loop is provable untaken. I haven't been able to find a test case to demonstrate the miscompile.

Issue 2 - For modules without a data layout, we can end up with unsized pointer typed exit counts. Just bail out of this case.

I think these are the last two issues which need addressed before we enable this by default. The code has already survived a decent amount of fuzzing without revealing either of the above.

Differential Revision: https://reviews.llvm.org/D69695
2019-11-06 14:04:45 -08:00
Roman Lebedev
4fe94d0331
[LoopUnroll] countToEliminateCompares(): fix handling of [in]equality predicates (PR43840)
Summary:
I believe this bisects to https://reviews.llvm.org/D44983
(`[LoopUnroll] Only peel if a predicate becomes known in the loop body.`)

While that revision did contain tests that showed arguably-subpar peeling
for [in]equality predicates that [not] happen in the middle of the loop,
it also disabled peeling for the *first* loop iteration,
because latch would be canonicalized to [in]equality comparison..

That was intentional as per https://reviews.llvm.org/D44983#1059583.
I'm not 100% sure that i'm using correct checks here,
but this fix appears to be going in the right direction..

Let me know if i'm missing some checks here..

Fixes [[ https://bugs.llvm.org/show_bug.cgi?id=43840 | PR43840 ]].

Reviewers: fhahn, mkazantsev, efriedma

Reviewed By: fhahn

Subscribers: xbolva00, hiraditya, zzheng, llvm-commits, fhahn

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69617
2019-11-06 15:08:59 +03:00
Sjoerd Meijer
6c2a4f5ff9 [TTI][LV] preferPredicateOverEpilogue
We have two ways to steer creating a predicated vector body over creating a
scalar epilogue. To force this, we have 1) a command line option and 2) a
pragma available. This adds a third: a target hook to TargetTransformInfo that
can be queried whether predication is preferred or not, which allows the
vectoriser to make the decision without forcing it.

While this change behaves as a non-functional change for now, it shows the
required TTI plumbing, usage of this new hook in the vectoriser, and the
beginning of an ARM MVE implementation. I will follow up on this with:
- a complete MVE implementation, see D69845.
- a patch to disable this, i.e. we should respect "vector_predicate(disable)"
  and its corresponding loophint.

Differential Revision: https://reviews.llvm.org/D69040
2019-11-06 10:14:20 +00:00
Alina Sbirlea
4b698645d3 [LoopRotationUtils] Check values are newly inserted into maps.
This is a cleanup that came up in D63680.
All values added to the ValueMaps should be newly added.
2019-11-05 13:40:10 -08:00
Sergey Dmitriev
82588e05cc [SLP] - Add couple safety checks to TreeEntry::dump(). NFC
Summary: Check for MainOp and AltOp for NULL before dereferencing or issue NULL.

Reviewers: Vasilis, dtemirbulatov, RKSimon, ABataev

Reviewed By: ABataev

Subscribers: mehdi_amini, hiraditya, dexonsmith, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69812
2019-11-05 09:57:30 -08:00
Kazu Hirata
893afb9ca1 [JumpThreading] Factor out code to merge basic blocks (NFC)
Summary:
This patch factors out code to merge a basic block with its sole
successor -- partly for readability and partly to facilitate an
upcoming patch of my own.

Reviewers: wmi

Subscribers: hiraditya, jfb, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69852
2019-11-05 09:46:57 -08:00
Gil Rapaport
100e797adb [LV] Apply sink-after & interleave-groups as VPlan transformations (NFC)
This recommits 2be17087f8c38934b7fc9208ae6cf4e9b4d44f4b (reverted in
d3ec06d219788801380af1948c7f7ef9d3c6100b for heap-use-after-free) with a fix
in IAI's reset() which was not clearing the set of interleave groups after
deleting them.
2019-11-05 17:29:13 +02:00
Francis Visoiu Mistrih
47d1029788 [ObjC][ARC] Ignore lifetime markers between *ReturnValue calls
When eliminating a pair of

`llvm.objc.autoreleaseReturnValue`

followed by

`llvm.objc.retainAutoreleasedReturnValue`

we need to make sure that the instructions in between are safe to
ignore.

Other than bitcasts and useless GEPs, it's also safe to ignore lifetime
markers for both static allocas (lifetime.start/lifetime.end) and dynamic
allocas (stacksave/stackrestore).

These get added by the inliner as part of the return sequence and can
prevent the transformation from happening in practice.

Differential Revision: https://reviews.llvm.org/D69833
2019-11-05 06:39:22 -08:00
Kazu Hirata
0016c1f400 [JumpThreading] Factor out common code to update the SSA form (NFC)
Summary:
This patch factors out common code to update the SSA form in
JumpThreading.cpp -- partly for readability and partly to facilitate
an coming patch of my own.

Reviewers: wmi

Subscribers: hiraditya, jfb, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69811
2019-11-05 06:15:44 -08:00
Simon Pilgrim
77debf51ab [GVN] Fix uninitialized variable warnings. NFCI. 2019-11-05 14:10:32 +00:00
Simon Pilgrim
1842fe6be3 Add missing GVN =operator. NFCI.
Fixes PVS Studio warning that the 'ValueTable' class implements a copy constructor, but lacks the '=' operator.
2019-11-05 13:41:50 +00:00
Roman Lebedev
ccf1a5f4bb
[InstCombine] dropRedundantMaskingOfLeftShiftInput(): truncation (PR42563)
Summary:
That fold keeps growing and growing :(
I think this may be one of the last pieces for it.

Since D67677/D67725, the fold knowns the general form
of the pattern - where some masking is needed:
https://rise4fun.com/Alive/F5R
https://rise4fun.com/Alive/gslRa

But there is one more huge piece missing - if you are extracting some bits,
it is not impossible that the origin is wider than the extraction,
i.e. there may be a truncation. And we don't deal with that yet.

But we can, and the generalization remains fully identical:
https://rise4fun.com/Alive/Uar
https://rise4fun.com/Alive/5SW

After a preparatory cleanup i think the diff looks rather clean.

One missing piece is that in some patterns (especially pat. b),
`-1` only needs to be `-1` in final type, but that is for later..

https://bugs.llvm.org/show_bug.cgi?id=42563

Reviewers: spatel, nikic

Reviewed By: spatel

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69125
2019-11-05 12:41:26 +03:00
Philip Reames
6ff439b57f [SimplifyCFG] Use a (trivially) dominanting widenable branch to remove later slow path blocks
This transformation is a variation on the GuardWidening transformation we have checked in as it's own pass. Instead of focusing on merge (i.e. hoisting and simplifying) two widenable branches, this transform makes the observation that simply removing a second slowpath block (by reusing an existing one) is often a very useful canonicalization. This may lead to later merging, or may not. This is a useful generalization when the intermediate block has loads whose dereferenceability is hard to establish.

As noted in the patch, this can be generalized further, and will be.

Differential Revision: https://reviews.llvm.org/D69689
2019-11-04 11:03:28 -08:00
Amy Huang
ab76cfdd20 Recommit "[CodeView] Add option to disable inline line tables."
This reverts commit 004ed2b0d1b86d424643ffc88fce20ad8bab6804.
Original commit hash 6d03890384517919a3ba7fe4c35535425f278f89

Summary:
This adds a clang option to disable inline line tables. When it is used,
the inliner uses the call site as the location of the inlined function instead of
marking it as an inline location with the function location.

https://reviews.llvm.org/D67723
2019-11-04 09:15:26 -08:00
Alexey Bataev
b80c41cd3c [SLP]Fix PR43799: Crash on different sizes of GEP indices.
Summary:
If the GEP instructions are going to be vectorized, the indices in those
GEP instructions must be of the same type. Otherwise, the compiler may
crash when trying to build the vector constant.

Reviewers: RKSimon, spatel

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69627
2019-11-04 10:36:26 -05:00
Benjamin Kramer
d3ec06d219 Revert "[LV] Apply sink-after & interleave-groups as VPlan transformations (NFC)"
This reverts commit 2be17087f8c38934b7fc9208ae6cf4e9b4d44f4b. Fails ASAN.
2019-11-04 15:04:42 +01:00
David Spickett
91167e22ec [hwasan] Remove lazy thread-initialisation
This was an experiment made possible by a non-standard feature of the
Android dynamic loader.

It required introducing a flag to tell the compiler which ABI was being
targeted.
This flag is no longer needed, since the generated code now works for
both ABI's.

We leave that flag untouched for backwards compatibility. This also
means that if we need to distinguish between targeted ABI's again
we can do that without disturbing any existing workflows.

We leave a comment in the source code and mention in the help text to
explain this for any confused person reading the code in the future.

Patch by Matthew Malcomson

Differential Revision: https://reviews.llvm.org/D69574
2019-11-04 10:58:46 +00:00
Gil Rapaport
2be17087f8 [LV] Apply sink-after & interleave-groups as VPlan transformations (NFC)
The sink-after and interleave-group vectorization decisions were so far applied to
VPlan during initial VPlan construction, which complicates VPlan construction – also because of
their inter-dependence. This patch refactors buildVPlanWithRecipes() to construct a simpler
initial VPlan and later apply both these vectorization decisions, in order, as VPlan-to-VPlan
transformations.

Differential Revision: https://reviews.llvm.org/D68577
2019-11-04 10:37:39 +02:00
Dávid Bolvanský
058b5028de Reland '[InstructionCombining] Fixed null check after dereferencing warning. NFCI.' 2019-11-03 20:34:54 +01:00
Dávid Bolvanský
5b37c018d5 Revert "[InstructionCombining] Fixed null check after dereferencing warning. NFCI."
This reverts commit 8308187fd9bfa08ffad0a636d4dd1d25e7de5a76. This exposed a bug.
2019-11-03 20:31:05 +01:00
Dávid Bolvanský
d825ed24d2 Revert "[InstructionCompares] Fixed null check after dereferencing warning. NFCI."
This reverts commit b8685cf3042f6a2e129061922bd6b18e3c42258e.
2019-11-03 20:24:01 +01:00
Dávid Bolvanský
b8685cf304 [InstructionCompares] Fixed null check after dereferencing warning. NFCI. 2019-11-03 20:13:45 +01:00
Dávid Bolvanský
8308187fd9 [InstructionCombining] Fixed null check after dereferencing warning. NFCI. 2019-11-03 20:10:46 +01:00
Dávid Bolvanský
8262a5b701 [CHR] Fixed null check after dereferencing warning. NFCI. 2019-11-03 20:06:38 +01:00
Dávid Bolvanský
914128ab12 [LoopUnrollRuntime] Fixed null check after dereferencing warning. NFCI. 2019-11-03 20:05:18 +01:00
Dávid Bolvanský
60cb193a40 [LoopUnrollAndJam] Fixed null check after dereferencing warning. NFCI. 2019-11-03 20:02:54 +01:00
Simon Pilgrim
81ba611e88 Ensure VPlanPrinter::Depth is initialized to fix static analyzer warning. NFCI. 2019-11-03 11:17:05 +00:00
Johannes Doerfert
77a6b358b5 [Attributor][NFCI] Do not track unnecessary dependences
If we do not look at assumed information there is no need to track
dependences.
2019-11-02 15:26:30 -05:00
Johannes Doerfert
680f638027 [Attributor][NFCI] Distinguish optional and required dependences
Dependences between two abstract attributes SRC and TRG come naturally in
two flavors:
  Either (1) "some" information of SRC is *required* for TRG to derive
  information, or (2) SRC is just an *optional* way for TRG to derive
  information.

While it is not strictly necessary to distinguish these types
explicitly, it can help us to converge faster, in terms of iterations,
and also cut down the number of `AbstractAttribute::update` calls.

As far as I can tell, we only use optional dependences for liveness so
far but that might change in the future. With this change the Attributor
can be informed about the "dependence class" and it will perform
appropriate actions when an Attribute is set to an invalid state, thus
one that cannot be used by others to derive information from.
2019-11-02 15:26:22 -05:00
Stefan Stipanovic
f35740d6e9 NoFree argument attribute.
Summary: Deducing nofree atrribute for function arguments.

Reviewers: jdoerfert

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67886
2019-11-02 19:40:48 +01:00
Stefan Stipanovic
5fb1782918 Revert "NoFree argument attribute."
This reverts commit c12efa2ed0547f7f9f8fba0ad7a76a4cb08bf53a.
2019-11-02 17:31:02 +01:00
Stefan Stipanovic
c12efa2ed0 NoFree argument attribute.
Summary: Deducing nofree atrribute for function arguments.

Reviewers: jdoerfert

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67886
2019-11-02 16:35:38 +01:00
Roman Lebedev
c4b757be02
Revert BCmp Loop Idiom recognition transform (PR43870)
As discussed in https://bugs.llvm.org/show_bug.cgi?id=43870,
this transform is missing a crucial legality check:
the old (non-countable) loop would early-return upon first mismatch,
but there is no such guarantee for bcmp/memcmp.

We'd need to ensure that [PtrA, PtrA+NBytes) and [PtrB, PtrB+NBytes)
are fully dereferenceable memory regions. But that would limit
the transform to constant loop trip counts and would further
cripple it because dereferenceability analysis is *very* partial.

Furthermore, even if all that is done, every single test
would need to be rewritten from scratch.

So let's just give up.
2019-11-02 12:48:03 +03:00
Johannes Doerfert
2d77b0cad0 [Attributor] Ignore BlockAddress users in call site traversal
BlockAddress users will not "call" the function so they do not qualify
as call sites in the first place. When we delete a function with
BlockAddress users we need to first remove the body so they are properly
discarded.
2019-11-02 01:23:18 -05:00
Johannes Doerfert
07d16424f2 [Attributor][FIX] Do not try to cast if a cast is not required
When we replace constant returns at the call site we did issue a cast in
the hopes it would be a no-op if the types are equal. Turns out that is
not the case and we have to check it ourselves first.

Reused an IPConstantProp test for coverage. No functional change to the
test wrt. IPConstantProp.
2019-11-02 00:54:00 -05:00
Johannes Doerfert
c7ab19dbb0 [Attributor][FIX] Transform invoke of nounwind to call + br %normal_dest
Even if the invoked function may-return, we can replace it with a call
and branch if it is nounwind. We had almost everything in place to do
this but did not which actually caused a crash when we removed the
landingpad from the actually dead unwind block.

Exposed by the IPConstantProp tests.
2019-11-02 00:54:00 -05:00
Johannes Doerfert
3cbe3314b4 [Attributor][FIX] Make "known" and "assumed" liveness explicit
We did merge "known" and "assumed" liveness information into a single
set which caused various kinds of problems, especially because we did
not properly record when something was actually known. With this patch
we properly track the "known" bit and distinguish dead ends we know from
the ones we still need to explore in future updates.
2019-11-02 00:49:29 -05:00
Johannes Doerfert
1b6041a9e8 [Attributor] willreturn + noreturn = UB
We gave up on `noreturn` if `willreturn` was known for a while but we
now again try to always derive `noreturn`. This is useful because a
function that is `noreturn` + `willreturn` is basically dead as
executing it would lead to undefined behavior (UB).

This came up in the IPConstantProp cases where a function only contained
a unreachable but was not marked `noreturn` which caused missed
opportunities down the line.
2019-11-02 00:35:22 -05:00