This patch implement the VPlan-based cost model for VPReduction,
VPExtendedReduction and VPMulAccumulateReduction.
With this patch, we can calculate the reduction cost by the VPlan-based
cost model so remove the reduction costs in `precomputeCost()`.
Ref: Original instruction based implementation:
https://reviews.llvm.org/D93476
Now that there is only a single FindLastIV recurrence kind, simply pass
the sentinel value instead of the full recurrence descriptor to tighten
the interface.
Now that there is only a single AnyOf recurrence kind, simply pass the
start value instead of the full recurrence descriptor, to tighten the
interface.
Manage fast-math flags using VPIRFlags from VPInstruciton, in inline
with other VPInstructions. With this change, we now print the correctly
flags for ComputeReductionResult, other than that NFC.
This patch moves the logic to manage IR flags to a separate VPIRFlags
class. For now, VPRecipeWithIRFlags is the only class that inherits
VPIRFlags. The new class allows for simpler passing of flags when
constructing recipes, simplifying the constructors for various recipes
(VPInstruction in particular, which now just has 2 constructors, one
taking an extra VPIRFlags argument.
This mirrors the approach taken for VPIRMetadata and makes it easier to
extend in the future. The patch also adds a unified flagsValidForOpcode
to check if the flags in a VPIRFlags match the provided opcode.
PR: https://github.com/llvm/llvm-project/pull/140621
Building on top of https://github.com/llvm/llvm-project/pull/114305,
replace VPRegionBlocks with explicit CFG before executing.
This brings the final VPlan closer to the IR that is generated and
helps to simplify codegen.
It will also enable further simplifications of phi handling during
execution and transformations that do not have to preserve the
canonical IV required by loop regions. This for example could include
replacing the canonical IV with an EVL based phi while completely
removing the original canonical IV.
PR: https://github.com/llvm/llvm-project/pull/117506
This patch introduce two new recipes.
* VPExtendedReductionRecipe
- cast + reduction.
* VPMulAccumulateReductionRecipe
- (cast) + mul + reduction.
This patch also implements the transformation that match following
patterns via vplan and converts to abstract recipes for better cost
estimation.
* VPExtendedReduction
- reduce(cast(...))
* VPMulAccumulateReductionRecipe
- reduce.add(mul(...))
- reduce.add(mul(ext(...), ext(...))
- reduce.add(ext(mul(ext(...), ext(...))))
The converted abstract recipes will be lower to the concrete recipes
(widen-cast + widen-mul + reduction) just before recipe execution.
Note that this patch still relies on legacy cost model the calculate the
cost for these patters.
Will enable vplan-based cost decision in #113903.
Split from #113903.
Directly compute costs for binary ops and GEPs in
VPReplicateRecipe::computeCost. This simply ports the legacy cost
computation for uniform/replicating binary ops to the VPlan cost model.
Similarly to VPInstructionWithType and VPIRPhi, add VPPhi as a subclass
for VPInstruction. This allows implementing the VPPhiAccessors trait,
making available helpers for generic printing of incoming values /
blocks and accessors for incoming blocks and values.
It will also allow properly verifying def-uses for values used by
VPInstructions with PHI opcodes via
https://github.com/llvm/llvm-project/pull/124838.
PR: https://github.com/llvm/llvm-project/pull/139151
(NFC modulo debug output changes)
Add generic helper to print phi operands (incoming values) together with
their incoming blocks.
As more and more transforms are added, keeping the incoming blocks of
phis becomes more important. Print incoming blocks via VPPhiAcessors, to
make debugging easier.
Split off from #118638, this adds VPInstruction::StepVector, which
generates integer step vectors (0,1,2,...,VF). This is a step towards
eventually modelling all the separate parts of
VPWidenIntOrFpInductionRecipe in VPlan.
This is then used by VPWidenIntOrFpInductionRecipe, where we materialize
it just before unrolling so the operands stay in a fixed position.
The need for a separate operand in VPWidenIntOrFpInductionRecipe, as
well as the need to update it in
optimizeVectorInductionWidthForTCAndVFUF, should be removed with #118638
when everything is expanded in convertToConcreteRecipes.
Replace CreateTrunc with CreateSExtOrTrunc in VPScalarIVStepsRecipe to
safely handle type conversion. This prevents assertion failures from
invalid truncation when StartIdx0 has a smaller integer type than
IntStepTy. The assertion was introduced by commit 783a846.
Fixes https://github.com/llvm/llvm-project/issues/137185
We can reuse isVectorIntrinsicWithScalarOpAtArg in VectorUtils to
determine if only the first lane will be used for a
VPWidenIntrinsicRecipe, provided that we also move the VP EVL operand
check into it.
This was needed by a local patch I was working on that created a
VPWidenIntrinsicRecipe with a VP intrinsic, and prevents the need to
update the scalar arguments in two places.
Whenever calls were transformed to VP intrinsics with EVL tail folding
in #110412, this workaround was added in computeCost to avoid an
assertion when checking ICA.getArgs().
However it turned out that the actual arguments were never used and this
assertion was removed in #115983 afterwards, so it's now fine to leave
the arguments empty and use the type based cost instead.
The type based cost and value based cost are the same for these VP
intrinsics.
This was tested by adding back in the transformation code in #110412 and
checking that no assertions were still hit.
ExtractFromEnd only has 2 uses, extracting the last and penultimate
elements. Replace it with 2 separate opcodes, removing the need to
materialize and handle a constant argument.
PR: https://github.com/llvm/llvm-project/pull/137030
Add a new helper to manage IR metadata that can be progated to generated
instructions for recipes.
This helps to remove a number of remaining uses of getUnderlyingInstr
during VPlan execution.
PR: https://github.com/llvm/llvm-project/pull/135272
Add incoming exit phi operands during the initial VPlan construction.
This ensures all users are added to the initial VPlan and is also needed
in preparation to retaining exiting edges during initial construction.
PR: https://github.com/llvm/llvm-project/pull/136455
Some vector math routines, e.g. ArmPL, specify a particular
calling convention on the routines which can help improve
performance by specifying what registers have to be preserved
across the call.
This patch adds a WideIVStep opcode that can be used to create a vector
with the steps to increment a wide induction. The opcode has 2 operands
* the vector step
* the scale of the vector step
The opcode is later converted into a sequence of recipes that convert
the scale and step to the target type, if needed, and then multiply
vector step by scale.
This simplifies code that needs to materialize step vectors, e.g.
replacing wide IVs as follow up to
https://github.com/llvm/llvm-project/pull/108378 with an increment of
the wide IV step.
PR: https://github.com/llvm/llvm-project/pull/119284
There are some opcodes that currently require specialized recipes, due
to their result type not being implied by their operands, including
casts.
This leads to duplication from defining multiple full recipes.
This patch introduces a new VPInstructionWithType subclass that also
stores the result type. The general idea is to have opcodes needing to
specify a result type to use this general recipe. The current patch
replaces VPScalarCastRecipe with VInstructionWithType, a similar patch
for VPWidenCastRecipe will follow soon.
There are a few proposed opcodes that should also benefit, without the
need of workarounds:
* https://github.com/llvm/llvm-project/pull/129508
* https://github.com/llvm/llvm-project/pull/119284
PR: https://github.com/llvm/llvm-project/pull/129706
