No need to include the order of the scalars beeing used as part of the
alternate vectorization into account when trying to reorder the whole
graph. Such elements better to reorder in the following phase because
the subtree still ends up in shuffle.
Part of D116688, fixes the regression in D116690.
Differential Revision: https://reviews.llvm.org/D116740
There is a bug in the reordering analysis stage. If the element with the
given hash is not added to the map but has the same number of APOs and
instructions with same parent, but different instruction opcode, it will
be initalized with default values and then the counter is increased by
1. But the lane is not updated and default to 0 instead of the actual
`Lane` value. It leads to the fact that the analysis is useless in
many cases and default to lane 0 instead of actual lane with the
minimum amount of APO operands.
Differential Revision: https://reviews.llvm.org/D116690
This was originally added in rG22174f5d5af1eb15b376c6d49e7925cbb7cca6be
although that patch doesn't really mention any reasons for ignoring the
pointer type in this calculation if the memory access isn't consecutive.
Reviewed By: david-arm
Differential Revision: https://reviews.llvm.org/D115356
At the moment, the primary induction variable for the vector loop is
created as part of the skeleton creation. This is tied to creating the
vector loop latch outside of VPlan. This prevents from modeling the
*whole* vector loop in VPlan, which in turn is required to model
preheader and exit blocks in VPlan as well.
This patch introduces a new recipe VPCanonicalIVPHIRecipe to represent the
primary IV in VPlan and CanonicalIVIncrement{NUW} opcodes for
VPInstruction to model the increment.
This allows us to partly retire createInductionVariable. At the moment,
a bit of patching up is done after executing all blocks in the plan.
Reviewed By: Ayal
Differential Revision: https://reviews.llvm.org/D113223
For loops that contain in-loop reductions but no loads or stores, large
VFs are chosen because LoopVectorizationCostModel::getSmallestAndWidestTypes
has no element types to check through and so returns the default widths
(-1U for the smallest and 8 for the widest). This results in the widest
VF being chosen for the following example,
float s = 0;
for (int i = 0; i < N; ++i)
s += (float) i*i;
which, for more computationally intensive loops, leads to large loop
sizes when the operations end up being scalarized.
In this patch, for the case where ElementTypesInLoop is empty, the widest
type is determined by finding the smallest type used by recurrences in
the loop instead of falling back to a default value of 8 bits. This
results in the cost model choosing a more sensible VF for loops like
the one above.
Differential Revision: https://reviews.llvm.org/D113973
This reverts commit fd4808887e.
This patch causes gcc to issue a lot of warnings like:
warning: base class ‘class llvm::MCParsedAsmOperand’ should be
explicitly initialized in the copy constructor [-Wextra]
Setting the loop metadata for the vector loop after VPlan execution
allows generating the full loop body during VPlan execution. This is in
preparation for D113224.
Rather than checking for nounwind in particular, make sure the
instruction is guaranteed to transfer execution, which will also
handle non-willreturn calls correctly.
Fixes https://github.com/llvm/llvm-project/issues/52950.
VPWidenCanonicalIVRecipe does not create PHI instructions, so it does
not need to be placed in the phi section of a VPBasicBlock.
Also tidies the code so the WidenCanonicalIV recipe and the
compare/lane-masks are created in the header.
Discussed D113223.
Reviewed By: Ayal
Differential Revision: https://reviews.llvm.org/D116473
Need to clear CurrentOrder order mask if it is determined that
extractelements form identity order and need to use a vector-like
construct when iterating over ordered entries in the reorderTopToBottom
function.
This patch adds a new prepareToExecute helper to set up live-ins, so
VPTransformState doesn't need to hold values like TripCount.
This also requires making the trip count operand for ActiveLaneMask
explicit in VPlan.
Reviewed By: Ayal
Differential Revision: https://reviews.llvm.org/D116320
We should not lose analysis precision if an 'add' has both no-wrap
flags (nsw and nuw) compared to just one or the other.
This patch is modeled on a similar construct that was added with
D59386.
I don't think it is possible to expose a problem with an unsigned
compare because of the way this was coded (nuw is handled first).
InstCombine has an assert that fires with the example from:
https://github.com/llvm/llvm-project/issues/52884
...because it was expecting InstSimplify to handle this kind of
pattern with an smax.
Fixes#52884
Differential Revision: https://reviews.llvm.org/D116322
Not all header phis widen the phi, e.g. like the new
VPCanonicalIVPHIRecipe in D113223. To let those recipes also inherit
from a phi-like base class, add a more generic VPHeaderPHIRecipe
abstract base class.
Reviewed By: Ayal
Differential Revision: https://reviews.llvm.org/D116304
By creating the header and latch blocks up front and adding blocks and
recipes in between those 2 blocks we ensure that the entry and exits of
the plan remain valid throughout construction.
In order to avoid test changes and keep printing of the plans the same,
we use the new header block instead of creating a new block on the first
iteration of the loop traversing the original loop.
We also fold the latch into its predecessor.
This is a follow up to a post-commit suggestion in D114586.
Reviewed By: Ayal
Differential Revision: https://reviews.llvm.org/D115793
The availability of SVE should be sufficient to enable scalable
auto-vectorization.
This patch adds a new TTI interface to query the target what style of
vectorization it wants when scalable vectors are available. For other
targets than AArch64, this currently defaults to 'FixedWidthOnly'.
Differential Revision: https://reviews.llvm.org/D115651
Need to check for the number of the unique non-constant values since the
unique values may include several constants.
Differential Revision: https://reviews.llvm.org/D115939
Need to check for the number of the unique non-constant values since the
unique values may include several constants.
Differential Revision: https://reviews.llvm.org/D115939
Pass in the vector header instead of relying on ILV::LoopVectorBody.
This reduces the dependence on state from ILV. Where VPTransformState is
available, State.CFG.PrevBB can be used.
Need to early exit out of the reordering process if the perfect/shuffled match is found in the operands. Such pattern will result in not profitable reordering because of (false positive) external use of scalars.
Differential Revision: https://reviews.llvm.org/D115811
These are deprecated and should be replaced with getAlign().
Some of these asserts don't do anything because Load/Store/AllocaInst never have a 0 align value.
No need to represent splats as a node with the reused scalars, it may
increase the cost (currently pass just ignores extra shuffle cost and it
is still not correct).
Differential Revision: https://reviews.llvm.org/D115800
Changes the preliminary multinode analysis:
1. Introduced scores for reversed loads/extractelements.
2. Improved shallow score calculation.
3. Lowered the cost of external uses (no need to consider it several times, just ones).
4. The initial lane for analysis is the one with the minimal possible
reorderings.
These changes in general shall reduce compile time and improve the
reordering in many cases.
Part of D57059.
Differential Revision: https://reviews.llvm.org/D101109
If the gather node is a mix of undefvalues and exractelement
instructions, need to take the ordering for such nodes into account too.
It allows to reorder some (sub)trees and remove some extra shuffles,
improving overall vectorization.
Also, outlined common functionality into a separate function.
Differential Revision: https://reviews.llvm.org/D115358
For the simple copy loop (see test case) vectorizer selects VF equal to 32 while the loop is known to have 17 iterations only. Such behavior makes no sense to me since such vector loop will never be executed. The only case we may want to select VF large than TC is masked vectoriztion. So I haven't touched that case.
Reviewed By: dmgreen
Differential Revision: https://reviews.llvm.org/D114528