Most folds based on these matchers already check to make sure the
condition type is the same as the select type, and it seems unlikely
that a fold would want to handle a scalar-select-of-vectors pattern
(there are no regression tests for it).
This is a preliminary step for fixing #issue 58552. The fold(s)
responsible for that crash (D101807, D101375) don't use the matchers
yet, but they probably should.
Differential Revision: https://reviews.llvm.org/D137170
The InstCombine test is reduced from issue #56601. Without the more
liberal match for ConstantExpr, we try to rearrange constants in
Negator forever.
Alternatively, we could adjust the definition of m_ImmConstant to be
more conservative, but that's probably a larger patch, and I don't
see any downside to changing m_ConstantExpr. We never capture and
modify a ConstantExpr; transforms just want to avoid it.
Differential Revision: https://reviews.llvm.org/D130286
This enabled opaque pointers by default in LLVM. The effect of this
is twofold:
* If IR that contains *neither* explicit ptr nor %T* types is passed
to tools, we will now use opaque pointer mode, unless
-opaque-pointers=0 has been explicitly passed.
* Users of LLVM as a library will now default to opaque pointers.
It is possible to opt-out by calling setOpaquePointers(false) on
LLVMContext.
A cmake option to toggle this default will not be provided. Frontends
or other tools that want to (temporarily) keep using typed pointers
should disable opaque pointers via LLVMContext.
Differential Revision: https://reviews.llvm.org/D126689
We needed a stricter version of m_Not for D114462, but I wasn't
sure if that was going to be required anywhere else, so I didn't bother
to make that reusable.
It turns out we have one more existing simplification that needs
this (currently miscompiles):
https://alive2.llvm.org/ce/z/9-nTKi
And there's at least one more fold in that family that we could add.
Differential Revision: https://reviews.llvm.org/D114882
There's precedent for that in `CreateOr()`/`CreateAnd()`.
The motivation here is to avoid bloating the run-time check's IR
in `SCEVExpander::generateOverflowCheck()`.
Refs. https://reviews.llvm.org/D109368#3089809
Stop using APInt constructors and methods that were soft-deprecated in
D109483. This fixes all the uses I found in llvm, except for the APInt
unit tests which should still test the deprecated methods.
Differential Revision: https://reviews.llvm.org/D110807
This patch is for fixing potential insertElement-related bugs like D93818.
```
V = UndefValue::get(VecTy);
for(...)
V = Builder.CreateInsertElementy(V, Elt, Idx);
=>
V = PoisonValue::get(VecTy);
for(...)
V = Builder.CreateInsertElementy(V, Elt, Idx);
```
Like above, this patch changes the placeholder V to poison.
The patch will be separated into several commits.
Reviewed By: aqjune
Differential Revision: https://reviews.llvm.org/D110311
This renames the primary methods for creating a zero value to `getZero`
instead of `getNullValue` and renames predicates like `isAllOnesValue`
to simply `isAllOnes`. This achieves two things:
1) This starts standardizing predicates across the LLVM codebase,
following (in this case) ConstantInt. The word "Value" doesn't
convey anything of merit, and is missing in some of the other things.
2) Calling an integer "null" doesn't make any sense. The original sin
here is mine and I've regretted it for years. This moves us to calling
it "zero" instead, which is correct!
APInt is widely used and I don't think anyone is keen to take massive source
breakage on anything so core, at least not all in one go. As such, this
doesn't actually delete any entrypoints, it "soft deprecates" them with a
comment.
Included in this patch are changes to a bunch of the codebase, but there are
more. We should normalize SelectionDAG and other APIs as well, which would
make the API change more mechanical.
Differential Revision: https://reviews.llvm.org/D109483
This fixes https://reviews.llvm.org/D93990#2666922
by teaching `m_Undef` to match vectors/aggrs with poison elements.
As suggested, fixes in InstCombine files to use the `m_Undef` matcher instead
of `isa<UndefValue>` will be followed.
Reviewed By: lebedev.ri
Differential Revision: https://reviews.llvm.org/D100122
As mentioned in D93793, there are quite a few places where unary `IRBuilder::CreateShuffleVector(X, Mask)` can be used
instead of `IRBuilder::CreateShuffleVector(X, Undef, Mask)`.
Let's update them.
Actually, it would have been more natural if the patches were made in this order:
(1) let them use unary CreateShuffleVector first
(2) update IRBuilder::CreateShuffleVector to use poison as a placeholder value (D93793)
The order is swapped, but in terms of correctness it is still fine.
Reviewed By: spatel
Differential Revision: https://reviews.llvm.org/D93923
This patch adds a new matcher for single index InsertValue instructions,
similar to the existing matcher for ExtractValue.
Reviewed By: lebedev.ri
Differential Revision: https://reviews.llvm.org/D91352
This adds matchers m_NonNaN, m_NonInf, m_Finite and m_NonZeroFP as well
as generic support for binding the matched value to an APFloat.
I tried to follow the existing convention of using an FP suffix for
predicates like zero and non-zero, which could be confused with the
integer versions, but not for predicates which are clearly already
FP-specific.
Differential Revision: https://reviews.llvm.org/D89038
I skimmed the existing users of these matchers and don't see any problems
(eg, the caller assumes the matched value was a select instruction without checking).
So I think we can generalize the matching to allow the new intrinsics or the cmp+select idioms.
I did not find any unit tests for the matchers, so added some basics there. The instsimplify
tests are adapted from existing tests for the cmp+select pattern and cover the folds in
simplifyICmpWithMinMax().
Differential Revision: https://reviews.llvm.org/D85230
Instead, represent the mask as out-of-line data in the instruction. This
should be more efficient in the places that currently use
getShuffleVector(), and paves the way for further changes to add new
shuffles for scalable vectors.
This doesn't change the syntax in textual IR. And I don't currently plan
to change the bitcode encoding in this patch, although we'll probably
need to do something once we extend shufflevector for scalable types.
I expect that once this is finished, we can then replace the raw "mask"
with something more appropriate for scalable vectors. Not sure exactly
what this looks like at the moment, but there are a few different ways
we could handle it. Maybe we could try to describe specific shuffles.
Or maybe we could define it in terms of a function to convert a fixed-length
array into an appropriate scalable vector, using a "step", or something
like that.
Differential Revision: https://reviews.llvm.org/D72467
The current m_APInt() and m_APFloat() matchers do not accept splats
that include undefs (unlike m_Zero() and other matchers for specific
values). We can't simply change the default behavior, as there are
existing transforms that would not be safe with undefs.
For this reason, I'm introducing new m_APIntAllowUndef() and
m_APFloatAllowUndef() matchers, that allow splats with undefs.
Additionally, m_APIntForbidUndef() and m_APFloatForbidUndef() are
added. These have the same behavior as the existing m_APInt() and
m_APFloat(), but serve as an explicit indication that undefs were
considered and found unsound for this transform. This helps
distinguish them from existing uses of m_APInt() where we do not
know whether undefs can or cannot be allowed without additional review.
Differential Revision: https://reviews.llvm.org/D72975
Summary: Also adds a test to the pattern matching unit tests.
Reviewers: spatel, craig.topper, RKSimon, majnemer, lebedev.ri
Reviewed By: spatel
Subscribers: merge_guards_bot, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D70892
Used in D69245, these add pattern matchers for the WithOverflowInst
(capturing the result) and the ExtractValue instructions taking a
template parameter specifying the element being extracted.
m_SExtOrSelf() is for consistency.
m_ZExtOrSExtOrSelf() is motivated by the D68103/r373106 :
sometimes it is useful to look past any extensions of the shift amount,
and m_ZExtOrSExtOrSelf() may be exactly the tool to do that.
llvm-svn: 373128
Currently m_Br only takes references to BasicBlock*, which limits its
flexibility. For example, you have to declare a variable, even if you
ignore the result or you have to have additional checks to make sure the
matched BB matches an expected one.
This patch adds m_BasicBlock and m_SpecificBB matchers, which can be
used like the existing matchers for constants or values.
I also had a look at the existing uses and updated a few. IMO it makes
the code a bit more explicit.
Reviewers: spatel, craig.topper, RKSimon, majnemer, lebedev.ri
Reviewed By: lebedev.ri
Differential Revision: https://reviews.llvm.org/D68013
llvm-svn: 372885
Summary:
It is a good idea to do as much matching inside of `match()` as possible.
If some checking is done afterwards, and we don't fold because of it,
chances are we may have missed some commutative pattern.
Reviewers: spatel, craig.topper, RKSimon
Reviewed By: spatel, RKSimon
Subscribers: llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D64038
llvm-svn: 367017
Summary:
I don't think it already exists? I don't see it at least.
It is important to have it because else we'll do some checks after `match()`,
and that may result in missed folds in commutative nodes.
Reviewers: spatel, craig.topper, RKSimon, majnemer
Reviewed By: spatel
Subscribers: llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D64037
llvm-svn: 367016
Summary: Provides m_LibFunc pattern that can be used to match LibFuncs.
Reviewers: spatel, hfinkel, efriedma, lebedev.ri
Reviewed By: lebedev.ri
Subscribers: lebedev.ri, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D42047
llvm-svn: 366069
Summary:
Match an integer or vector with every element unsigned less than the
Threshold. For vectors, this includes constants with undefined elements.
FIXME: is it worth generalizing this to simply take ICmpInst::Predicate?
Reviewers: craig.topper, spatel, nikic
Reviewed By: spatel
Subscribers: llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D63811
llvm-svn: 364711
This cleans up all LoadInst creation in LLVM to explicitly pass the
value type rather than deriving it from the pointer's element-type.
Differential Revision: https://reviews.llvm.org/D57172
llvm-svn: 352911
to reflect the new license.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
llvm-svn: 351636
This patch fixes the issue noticed in D54532.
The problem is that cst_pred_ty-based matchers like m_Zero() currently do not match
scalar undefs (as expected), but *do* match vector undefs. This may lead to optimization
inconsistencies in rare cases.
There is only one existing test for which output changes, reverting the change from D53205.
The reason here is that vector fsub undef, %x is no longer matched as an m_FNeg(). While I
think that the new output is technically worse than the previous one, it is consistent with
scalar, and I don't think it's really important either way (generally that undef should have
been folded away prior to reassociation.)
I've also added another test case for this issue based on InstructionSimplify. It took some
effort to find that one, as in most cases undef folds are either checked first -- and in the
cases where they aren't it usually happens to not make a difference in the end. This is the
only case I was able to come up with. Prior to this patch the test case simplified to undef
in the scalar case, but zeroinitializer in the vector case.
Patch by: @nikic (Nikita Popov)
Differential Revision: https://reviews.llvm.org/D54631
llvm-svn: 347318
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
Summary:
There aren't any matchers for the three vector operations: insertelement, extractelement, and
shufflevector. This patch adds them as well as corresponding unit tests.
llvm-svn: 328709
Previously, the matching was done incorrectly for the case where
operands for FCmpInst and SelectInst were in opposite order.
Patch by Andrei Elovikov.
Differential Revision: https://reviews.llvm.org/D33185
llvm-svn: 305308