Loop predication's predicateLoopExit pass does two incorrect things:
It sinks the widenable call into the loop, thereby converting an invariant condition to a variant one
It widens the widenable call at a branch thereby converting the branch into a loop-varying one.
The latter is problematic when the branch may have been loop-invariant
and prior optimizations (such as indvars) may have relied on this
fact, and updated the deopt state accordingly.
Now, when we widen this with a loop-varying condition, the deopt state
is no longer correct.
https://github.com/llvm/llvm-project/issues/61963 fixed.
Differential Revision: https://reviews.llvm.org/D147662
Instead of iterating over all LCSSA phis in the exit block, collect all
LiveOut users of the FOR splice VPInstruction and only update those
users.
Building on top of D147471, this removes an access to the cost model
after VPlan execution.
Depends on D147471.
Reviewed By: Ayal, michaelmaitland
Differential Revision: https://reviews.llvm.org/D147472
It is not actually used for any computations. Its only purpose is to
check that the loop is finite and find out the type of computed exit
count. Refactor code so that we only store this type.
Instead of clearing live outs when a scalar epilogue is required late,
don't add live outs during VPlan construction if a scalar epilogue is
required.
This enables more VPlan-based DCE (if the live out would be the only
user in the plan) and is a step towards removing an access of the cost
model in fixedVectorizedLoop (which is after VPlan execution).
Depends on D147468.
Reviewed By: Ayal
Differential Revision: https://reviews.llvm.org/D147471
This removes the need to convert the end of the range to the next
power-of-2 for the end iterator after 4bd3fda5124962 and was suggested
as follow-up TODO in D147468.
Add an iterator to iterate over all VFs in VFRange. This simplifies some
existing code and allows using all_of,any_of and none_of on a VFRange.
Reviewed By: Ayal
Differential Revision: https://reviews.llvm.org/D147468
Use clone to keep the metadata, the issue is reported
by aeubanks on D141188.
Reviewed By: nikic, paulwalker-arm
Differential Revision: https://reviews.llvm.org/D146702
Using the more robust log2 search allows us to fold more cases (same
logic as exists for idiv/irem).
Reviewed By: nikic
Differential Revision: https://reviews.llvm.org/D146347
dependencies.
Improved compiled time by the precomputing the mapping between gathered
scalars and their gather/buildvector nodes for later use in
isGatherShuffledEntry to avoid recomputing this map each time this
function is called.
This patch adds a NeedsMaskForGaps field to VPInterleaveRecipe to record
whether a mask for gaps is needed. This removes a dependence on the cost
model in VPlan code-generation.
Reviewed By: Ayal
Differential Revision: https://reviews.llvm.org/D147467
Unfortunately alive2 cannot prove the correctness due to fails by timeout even for
float type half.
However it should be correct. If a and b are not NaN, maximum and minimum will just
return different values (a and b) and take into account a + b == b + a this is the same.
If a or b is NaN, than maximum and minimum are equal to NaN and NaN + NaN is NaN.
a + b is also a NaN.
In terms of preserving fast flags, we cannot preserve ninf due to
minimum(NaN, Infinity) == maximum(NaN, Infinity) == NaN,
minimum(NaN, Infinity) +ninf maximum(NaN, Infinity) == NaN +ninf NaN = NaN
However transformation will change
minimum(NaN, Infinity) + maximum(NaN, Infinity) to NaN +ninf Infinity == poison.
But if fadd is marked as nnan, we can preserve because NaN +ninf/nnan NaN = poison as well.
The same optimization for
maximum(a,b) * minimum(a,b) => a * b
is added.
All said above for fadd is correct for fmul.
Reviewed By: mkazantsev
Differential Revision: https://reviews.llvm.org/D147299
Revert commit due to failure on buildbot:
error: 'match_combine_or' may not intend to support class template argument deduction
This reverts commit b86a06ef284f2637bef89bf5bb20157a8b195568.
Make adjustExtracts/needToDelay lambdas members of ShuffleInstructionBuilder to allow to overload them later for cost model.
Differential Revision: https://reviews.llvm.org/D147730
The original loop has O(MxN) since `is_contained` iterates over
all incoming values. This change makes it so only the phis
which use the value as an incoming value are iterated over so
it is now O(M).
Differential Revision: https://reviews.llvm.org/D146999
Conditionally setting MaskForGaps is only needed for loads. This avoid
re-computing MaskForGaps for stores.
Suggested as independent cleanup in D147467.
If the value is used in the expression, need to adjust the mask before
applying the mask. Plus, need to fix the analysis of the phi nodes for
reused scalars.
Made the condition for the erasing of the gathered extractelements
stricter, remove it only if it has single vectorized use, otherwise
leave it for instcombiner/instsimplify analysis.
Correctly handle the case of splitting an alloca which backs contiguous
distinct variables, where a slice's size equals the size of a backed variable.
We need to ensure that we don't generate fragments expressions with fragments
of the same size as the variable as this is a verifier error.
Prior to this patch a fragment expression would be created in this
situation. e.g. splitting an alloca i64 with two adjacent 32-bit variables into
two 32-bit allocas, the new dbg.assign expressions would contain
(DW_OP_LLVM_fragment, 0, 32) and (DW_OP_LLVM_fragment, 32, 32) even though
those fragments cover each variable entirely.
Reviewed By: jmorse
Differential Revision: https://reviews.llvm.org/D147696
Re-write the code to avoid iteration over users of
constants and global values.
Reviewed By: mkazantsev
Differential Revision: https://reviews.llvm.org/D147450
In getInstructionCost if we know a zext/sext is going to be shrunk
we should only be changing the destination type, and leave the
source type unchanged. For example, we may change a zext from
zext <16 x i8> %a to <16 x i32>
to
zext <16 x i8> %a to <16 x i16>
However, we were previously calculating the cost for doing
zext <16 x i16> %a to <16 x i16>
which is incorrect.
Differential Revision: https://reviews.llvm.org/D147152
This patch is making sure that we use getTopMostExitingLoop when
finding out which loops to forget, when dealing with
unswitchNontrivialInvariants and unswitchTrivialSwitch. It seems
to at least be needed for unswitchNontrivialInvariants as detected
by the included test case.
Note that unswitchTrivialBranch already used getTopMostExitingLoop.
This was done in commit 4a9cde5a791cd49b96993e6. The commit
message in that commit says "If the patch makes sense, I will also
update those places to a similar approach ...", referring to these
functions mentioned above. As far as I can tell that never happened,
but this is an attempt to finally fix that.
Fixes https://github.com/llvm/llvm-project/issues/61080
Differential Revision: https://reviews.llvm.org/D147058
Patch generalizes analysis of scalars. The main part is outlined into
lambda, which can be used to find reused inserted scalars and emit
shuffle for them instead of multiple insertelement instructions, if the
permutation is found alreadyi. I.e. some scalars are transformed by the
permutation of previously vectorized nodes, and some are inserted
directly.
Reworked part of D110978
Differential Revision: https://reviews.llvm.org/D146564
(JFYI - This has been heavily reframed since original attempt at landing.)
This change updates the InductionDescriptor logic to allow matching a pointer IV with a non-constant stride, but also updates the LoopVectorizer to bailout on such descriptors by default. This preserves the default vectorizer behavior.
In review, it was pointed out that there's multiple unfortunate performance implications which need to be addressed before this can be enabled. Having a flag allows us to exercise the behavior, and write test cases for logic which is otherwise unreachable (or hard to reach).
This will also enable non-constant stride pointer recurrences for other consumers. I've audited said code, and don't see any obvious issues.
Differential Revision: https://reviews.llvm.org/D147336
Limit to dot product lowering to column major matrixes for now. This
simplifies the code and reasoning for upcoming planned improvements.
Support for row-major matrixes can be added later as extension.
/data/llvm-project/llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp:32:15: error: function 'decomposeSimpleLinearExpr' is not needed and will not be emitted [-Werror,-Wunneeded-internal-declaration]
static Value *decomposeSimpleLinearExpr(Value *Val, unsigned &Scale,
^
1 error generated.
canonicalizeLogicFirst reorders logic op / math op for suitable
constants, and this commit makes this function pass through
nsw/nuw flags on the Add.
Differential Revision: https://reviews.llvm.org/D147568
For poison-generating (rather than IUB) metadata, only copy it
from the dominating must-exec load if it is combined with !noundef.
This could be further extended by additionall intersecting the
metadata from all loads, which does not require !noundef.
createFragmentExpression will fail if it determines that the expression cannot
be split over fragments. Handle this case in SROA. Similarly to D147312 this
should be a rare occurrence as the `dbg.assign` will usually reference the
`Value` being stored without modifying it with a `DIExpression`.
Reviewed By: jmorse
Differential Revision: https://reviews.llvm.org/D147431
LLVM has the ability to vectorize using function variants that require
a mask by creating an all-true mask, and to vectorize a conditional
call via scalarization, now we want to join the two parts together
and use a masked variant when a mask is required.
Reviewed By: david-arm
Differential Revision: https://reviews.llvm.org/D136251
