This patch adds support for fragment expressions
TryToShrinkGlobalToBoolean() which were previously just dropped.
Thanks to Reid Kleckner for providing me a reproducer!
llvm-svn: 331086
Summary:
Currently, we
1. match `LHS` matcher to the `first` operand of binary operator,
2. and then match `RHS` matcher to the `second` operand of binary operator.
If that does not match, we swap the `LHS` and `RHS` matchers:
1. match `RHS` matcher to the `first` operand of binary operator,
2. and then match `LHS` matcher to the `second` operand of binary operator.
This works ok.
But it complicates writing of commutative matchers, where one would like to match
(`m_Value()`) the value on one side, and use (`m_Specific()`) it on the other side.
This is additionally complicated by the fact that `m_Specific()` stores the `Value *`,
not `Value **`, so it won't work at all out of the box.
The last problem is trivially solved by adding a new `m_c_Specific()` that stores the
`Value **`, not `Value *`. I'm choosing to add a new matcher, not change the existing
one because i guess all the current users are ok with existing behavior,
and this additional pointer indirection may have performance drawbacks.
Also, i'm storing pointer, not reference, because for some mysterious-to-me reason
it did not work with the reference.
The first one appears trivial, too.
Currently, we
1. match `LHS` matcher to the `first` operand of binary operator,
2. and then match `RHS` matcher to the `second` operand of binary operator.
If that does not match, we swap the ~~`LHS` and `RHS` matchers~~ **operands**:
1. match ~~`RHS`~~ **`LHS`** matcher to the ~~`first`~~ **`second`** operand of binary operator,
2. and then match ~~`LHS`~~ **`RHS`** matcher to the ~~`second`~ **`first`** operand of binary operator.
Surprisingly, `$ ninja check-llvm` still passes with this.
But i expect the bots will disagree..
The motivational unittest is included.
I'd like to use this in D45664.
Reviewers: spatel, craig.topper, arsenm, RKSimon
Reviewed By: craig.topper
Subscribers: xbolva00, wdng, llvm-commits
Differential Revision: https://reviews.llvm.org/D45828
llvm-svn: 331085
The idea is to have a pass which performs the same transformation as GuardWidening, but can be run within a loop pass manager without disrupting the pass manager structure. As demonstrated by the test case, this doesn't quite get there because of issues with post dom, but it gives a good step in the right direction. the motivation is purely to reduce compile time since we can now preserve locality during the loop walk.
This patch only includes a legacy pass. A follow up will add a new style pass as well.
llvm-svn: 331060
We currently support LCSSA PHI nodes in the outer loop exit, if their
incoming values do not come from the outer loop latch or if the
outer loop latch has a single predecessor. In that case, the outer loop latch
will be executed only if the inner loop gets executed. If we have multiple
predecessors for the outer loop latch, it may be executed even if the inner
loop does not get executed.
This is a first step to support the case described in
https://bugs.llvm.org/show_bug.cgi?id=30472
Reviewers: efriedma, karthikthecool, mcrosier
Reviewed By: efriedma
Differential Revision: https://reviews.llvm.org/D43237
llvm-svn: 331037
It doesn't unwind, and the wrong marking leads to the creation of an
.eh_frame section when it isn't necessary.
Differential Revision: https://reviews.llvm.org/D46082
llvm-svn: 331008
Summary: If file stream arg is not captured and source is fopen, we could replace IO calls by unlocked IO ("_unlocked" function variants) to gain better speed,
Reviewers: efriedma, RKSimon, spatel, sanjoy, hfinkel, majnemer
Subscribers: lebedev.ri, llvm-commits
Differential Revision: https://reviews.llvm.org/D45736
llvm-svn: 331002
Summary:
Simplify integer add expression X % C0 + (( X / C0 ) % C1) * C0 to
X % (C0 * C1). This is a common pattern seen in code generated by the XLA
GPU backend.
Add test cases for this new optimization.
Patch by Bixia Zheng!
Reviewers: sanjoy
Reviewed By: sanjoy
Subscribers: efriedma, craig.topper, lebedev.ri, llvm-commits, jlebar
Differential Revision: https://reviews.llvm.org/D45976
llvm-svn: 330992
Summary:
Follow-up to D43690, the EliminateAvailableExternally pass currently
runs under -O0 and -O2 and up. Under -O1 we would still want to drop
available_externally symbols to reduce space without inlining having
run.
Reviewers: tejohnson
Reviewed By: tejohnson
Subscribers: mehdi_amini, llvm-commits, kcc
Differential Revision: https://reviews.llvm.org/D46093
llvm-svn: 330961
Summary:
When performing indirect call promotion, current implementation inspects "all" parameters of the callsite and attemps to match with the formal argument type of the callee function. However, it is not possible to find the type for variable length arguments, and the compiler crashes when it attemps to match the type for variable lenght argument.
It seems that the bug is introduced with D40658. Prior to that, the type matching is performed only for the parameters whose ID is less than callee->getFunctionNumParams(). The attached test case will crash without the patch.
Reviewers: mssimpso, davidxl, davide
Reviewed By: mssimpso
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D46026
llvm-svn: 330844
As discussed in D45862, we want to delete parts of
this code because it can create more instructions
than it removes. But we also want to preserve some
folds that are winners, so tidy up what's here to
make splitting the good from bad a bit easier.
llvm-svn: 330841
This also means we have to check if the latch is the exiting block now,
as `transform` expects the latches to be the exiting blocks too.
https://bugs.llvm.org/show_bug.cgi?id=36586
Reviewers: efriedma, davide, karthikthecool
Reviewed By: efriedma
Differential Revision: https://reviews.llvm.org/D45279
llvm-svn: 330806
Summary:
When Reassociate is rewriting an expression tree it may
reuse old binary expression nodes, for new expressions.
Whenever an expression node is reused, but with a non-trivial
change in the result, we need to invalidate any debug info
that is associated with the node.
If for example rewriting
x = mul a, b
y = mul c, x
into
x = mul c, b
y = mul a, x
we still get the same result for 'y', but 'x' is a new expression.
All debug info referring to 'x' must be invalidated (marked as
optimized out) since we no longer calculate the expected value.
As a side-effect this patch avoid (at least some) problems where
reassociate could end up creating IR with debug-use before def.
Earlier the dbg.value nodes where left untouched in the IR, while
the reused binary nodes where sinked to just before the root node
of the rewritten expression tree. See PR27273 for more info about
such problems.
Reviewers: dblaikie, aprantl, dexonsmith
Reviewed By: aprantl
Subscribers: JDevlieghere, llvm-commits
Tags: #debug-info
Differential Revision: https://reviews.llvm.org/D45975
llvm-svn: 330804
Summary:
Use a MapVector instead of a DenseMap for RemMap since it is iteratated
over and the order of iteration can effect the order that new
instructions are created. This can in turn effect the use list order of
div/rem input values if multiple new instructions are created that share
any input values.
Reviewers: spatel
Subscribers: mcrosier, llvm-commits
Differential Revision: https://reviews.llvm.org/D45858
llvm-svn: 330792
update API for dominators rather than doing manual, hacky updates.
This is just the first step, but in some ways the most important as it
moves the non-trivial unswitching to update the domtree rather than
fully recalculating it each time.
Subsequent patches should remove the custom update logic used by the
trivial unswitch and replace it with uses of the update API.
This also fixes a number of bugs I was seeing when testing non-trivial
unswitch due to it querying the quasi-correct dominator tree. Now the
tree is 100% correct and safe to query. That said, there are still more
bugs I can see with non-trivial unswitch just running over the test
suite, so more bugfix patches are needed as well.
Thanks to both Sanjoy and Fedor for reviews and testing!
Differential Revision: https://reviews.llvm.org/D45943
llvm-svn: 330787
Patch #2 from VPlan Outer Loop Vectorization Patch Series #1
(RFC: http://lists.llvm.org/pipermail/llvm-dev/2017-December/119523.html).
This patch introduces the basic infrastructure to detect, legality check
and process outer loops annotated with hints for explicit vectorization.
All these changes are protected under the feature flag
-enable-vplan-native-path. This should make this patch NFC for the existing
inner loop vectorizer.
Reviewers: hfinkel, mkuper, rengolin, fhahn, aemerson, mssimpso.
Differential Revision: https://reviews.llvm.org/D42447
llvm-svn: 330739
After D43236, we started interchanging loops with empty dependence
matrices. In isProfitableForVectorization, we try to determine if
interchanging makes the loop dependences more friendly to the
vectorizer. If there are no dependences, we should not interchange,
based on that heuristic.
Reviewers: efriedma, mcrosier, karthikthecool, blitz.opensource
Reviewed By: mcrosier
Differential Revision: https://reviews.llvm.org/D45208
llvm-svn: 330738
The memory location an invariant load is using can never be clobbered by
any store, so it's safe to move the load ahead of the store.
Differential Revision: https://reviews.llvm.org/D46011
llvm-svn: 330725
loop unswitch.
This code incorrectly added the header to the loop block set early. As
a consequence we would incorrectly conclude that a nested loop body had
already been visited when the header of the outer loop was the preheader
of the nested loop. In retrospect, adding the header eagerly doesn't
really make sense. It seems nicer to let the cycle be formed naturally.
This will catch crazy bugs in the CFG reconstruction where we can't
correctly form the cycle earlier rather than later, and makes the rest
of the logic just fall out.
I've also added various asserts that make these issues *much* easier to
debug.
llvm-svn: 330707
This code path can very clearly be called in a context where we have
baselined all the cloned blocks to a particular loop and are trying to
handle nested subloops. There is no harm in this, so just relax the
assert. I've added a test case that will make sure we actually exercise
this code path.
llvm-svn: 330680
(notionally Scalar.h is part of libLLVMScalarOpts, so it shouldn't be
included by InstCombine which doesn't/shouldn't need to depend on
ScalarOpts)
llvm-svn: 330669
If a loop with child loops becomes our new inner loop after
interchanging, we only need to update LoopInfo for the blocks defined in
the old outer loop. BBs in child loops will stay there.
Reviewers: efriedma, karthikthecool, mcrosier
Reviewed By: efriedma
Differential Revision: https://reviews.llvm.org/D45970
llvm-svn: 330653
Summary: We do not need nonull attribute if we know an argument is going to be constant.
Reviewers: junbuml, davide, fhahn
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D45608
llvm-svn: 330641
Summary:
Skip basic blocks not reachable from the entry node
in MemCpyOptPass::iterateOnFunction.
Code that is unreachable may have properties that do not exist
for reachable code (an instruction in a basic block can for
example be dominated by a later instruction in the same basic
block, for example if there is a single block loop).
MemCpyOptPass::processStore is only safe to use for reachable
basic blocks, since it may iterate past the basic block
beginning when used for unreachable blocks. By simply skipping
to optimize unreachable basic blocks we can avoid asserts such
as "Assertion `!NodePtr->isKnownSentinel()' failed."
in MemCpyOptPass::processStore.
The problem was detected by fuzz tests.
Reviewers: eli.friedman, dneilson, efriedma
Reviewed By: efriedma
Subscribers: efriedma, llvm-commits
Differential Revision: https://reviews.llvm.org/D45889
llvm-svn: 330635
Summary:
This change teaches DSE that the atomic memory intrinsics are stores
that can be eliminated, and can allow other stores to be eliminated.
This change specifically does not teach DSE that these intrinsics
can be partially eliminated (i.e. length reduced, and dest/src changed);
that will be handled in another change.
Reviewers: mkazantsev, skatkov, apilipenko, efriedma, rsmith
Reviewed By: efriedma
Subscribers: dmgreen, llvm-commits
Differential Revision: https://reviews.llvm.org/D45535
llvm-svn: 330629
LoopRotate only invalidates innermost loops while the changes that it makes may
also affert any of this parents. With patch rL329047, SCEV becomes much smarter
about calculation of exit counts for outer loops, so we cannot assume that they are
not affected.
Differential Revision: https://reviews.llvm.org/D45945
llvm-svn: 330582
Current runtime unrolling invalidates parent loop saying that it might have changed
after the inner loop has changed, but it doesn't bother to do the same to its parents.
With patch rL329047, SCEV becomes much smarter about calculation of exit counts for
outer loops. We might need to invalidate not only the immediate parent, but also
any of its parents as well.
There is no clear evidence that there is some miscompile happening because of this
(at least I don't have such test), but the common sense says that the current code
is wrong.
Differential Revision: https://reviews.llvm.org/D45940
Reviewed By: chandlerc
llvm-svn: 330577
In the function `simplifyOneLoop` we optimistically assume that changes in the
inner loop only affect this very loop and have no impact on its parents. In fact,
after rL329047 has been merged, we can now calculate exit counts for outer
loops which may depend on inner loops. Thus, we need to invalidate all parents
when we do something to a loop.
There is an evidence of incorrect behavior of `simplifyOneLoop`: when we insert
`SE->verify()` check in the end of this funciton, it fails on a bunch of existing
test, in particular:
LLVM :: Transforms/LoopUnroll/peel-loop-not-forced.ll
LLVM :: Transforms/LoopUnroll/peel-loop-pgo.ll
LLVM :: Transforms/LoopUnroll/peel-loop.ll
LLVM :: Transforms/LoopUnroll/peel-loop2.ll
Note that previously we have fixed issues of this variety, see rL328483.
This patch makes this function invalidate the outermost loop properly.
Differential Revision: https://reviews.llvm.org/D45937
Reviewed By: chandlerc
llvm-svn: 330576
The condition this was asserting doesn't actually hold. I've added
comments to explain why, removed the assert, and added a fun test case
reduced out of 403.gcc.
llvm-svn: 330564
This is the last step in getting constant pattern matchers to allow
undef elements in constant vectors.
I'm adding a dedicated m_ZeroInt() function and building m_Zero() from
that. In most cases, calling code can be updated to use m_ZeroInt()
directly when there's no need to match pointers, but I'm leaving that
efficiency optimization as a follow-up step because it's not always
clear when that's ok.
There are just enough icmp folds in InstSimplify that can be used for
integer or pointer types, that we probably still want a generic m_Zero()
for those cases. Otherwise, we could eliminate it (and possibly add a
m_NullPtr() as an alias for isa<ConstantPointerNull>()).
We're conservatively returning a full zero vector (zeroinitializer) in
InstSimplify/InstCombine on some of these folds (see diffs in InstSimplify),
but I'm not sure if that's actually necessary in all cases. We may be
able to propagate an undef lane instead. One test where this happens is
marked with 'TODO'.
llvm-svn: 330550
When creating a call to storeStrong in ObjCARCContract, ensure the call
gets the correct funclet token, otherwise WinEHPrepare will turn the
call (and all subsequent instructions) into unreachable.
We already have logic to do this for the ARC autorelease elision marker;
factor that out into a common function that's used for both. These are
the only two places in this transform that create call instructions.
Differential Revision: https://reviews.llvm.org/D45857
llvm-svn: 330487
Summary:
Support the dynamic shadow memory offset (the default case for user
space now) and static non-zero shadow memory offset
(-hwasan-mapping-offset option). Keeping the the latter case around
for functionality and performance comparison tests (and mostly for
-hwasan-mapping-offset=0 case).
The implementation is stripped down ASan one, picking only the relevant
parts in the following assumptions: shadow scale is fixed, the shadow
memory is dynamic, it is accessed via ifunc global, shadow memory address
rematerialization is suppressed.
Keep zero-based shadow memory for kernel (-hwasan-kernel option) and
calls instreumented case (-hwasan-instrument-with-calls option), which
essentially means that the generated code is not changed in these cases.
Reviewers: eugenis
Subscribers: srhines, llvm-commits
Differential Revision: https://reviews.llvm.org/D45840
llvm-svn: 330475
The callback used to create an ORE for the legacy PI pass caches the allocated
object in a unique_ptr in the runOnModule function, and returns a reference to
that object. Under certian circumstances we can end up holding onto that
reference after the OREs destruction. Rather then allowing the new and legacy
passes to create ORE object in diffrent ways, create the ORE at the point of
use.
Differential Revision: https://reviews.llvm.org/D43219
llvm-svn: 330473