15 Commits

Author SHA1 Message Date
Florian Hahn
53266f73f0
[VPlan] Run DCE after unrolling.
This cleans up a number of dead recipes after unrolling if only their
first or last parts are used. This simplifies a number of tests.

Fixes https://github.com/llvm/llvm-project/issues/109581.
2024-09-22 22:08:46 +01:00
Florian Hahn
c48a1ebec1
[LV] Remove force-vector-width/force-vector-interleave from X86 test.
Update target-specific test to not force VF/UF, but instead use the
cost-model. There are similar tests arleady outside X86 and those force
VF & UF.

With this change, the target specific test checks the cost model.
Changes in picked VF/UF are limited to test_pr62954_scalar_epilogue_required,
and should preserve the original spirit of the test.
2024-09-17 08:59:24 +01:00
Florian Hahn
9a5a8731e7
[VPlan] Introduce ResumePhi VPInstruction, use to create phi for FOR. (#94760)
This patch introduces a new ResumePhi VPInstruction which creates a phi
in a leaf block of a VPlan. The first use is to create the phi node for
fixed-order recurrence resume values in the scalar preheader.

The VPInstruction takes 2 operands: 1) the incoming value from the
middle-block and a default value to be used for all other incoming
blocks.

In follow-up changes, it will also be used to create phis for reduction
and induction resume values.

Depends on https://github.com/llvm/llvm-project/pull/92651

PR: https://github.com/llvm/llvm-project/pull/94760
2024-07-11 16:08:04 +01:00
Florian Hahn
99d6c6d936
[VPlan] Model branch cond to enter scalar epilogue in VPlan. (#92651)
This patch moves branch condition creation to enter the scalar epilogue
loop to VPlan. Modeling the branch in the middle block also requires
modeling the successor blocks. This is done using the recently
introduced VPIRBasicBlock.

Note that the middle.block is still created as part of the skeleton and
then patched in during VPlan execution. Unfortunately the skeleton needs
to create the middle.block early on, as it is also used for induction
resume value creation and is also needed to properly update the
dominator tree during skeleton creation.

After this patch lands, I plan to move induction resume value and phi
node creation in the scalar preheader to VPlan. Once that is done, we
should be able to create the middle.block in VPlan directly.

This is a re-worked version based on the earlier
https://reviews.llvm.org/D150398 and the main change is the use of
VPIRBasicBlock.

Depends on https://github.com/llvm/llvm-project/pull/92525

PR: https://github.com/llvm/llvm-project/pull/92651
2024-07-05 10:08:42 +01:00
Florian Hahn
3808ba78de
[VPlan] Model middle block via VPIRBasicBlock. (#95816)
Use VPIRBasicBlock to wrap the middle block and implement patching up
branches in predecessors in VPIRBasicBlock::execute. The IR middle block
is only created after skeleton creation. Initially a regular
VPBasicBlock is created, which will later be replaced by a
VPIRBasicBlock once the middle IR basic block has been created.

Note that this slightly changes the order of instructions created in the
middle block; code generated by recipe execution in the middle block
will now be inserted before the terminator (and in between the compare
to used by the terminator). The original order will be restored in
https://github.com/llvm/llvm-project/pull/92651.


PR: https://github.com/llvm/llvm-project/pull/95816
2024-06-20 13:42:20 +01:00
Florian Hahn
998c33e5fc
[VPlan] Mark FirstOrderRecurrenceSplice as not having side-effects.
Now that FOR exit and resume value creation is explicitly modeled in
VPlan (05e1b5340b0caf1, 07b330132c0b) it doesn't depend on the first
order recurrence splice being preserved and it can now be marked as not
having side-effects. This allows removal of first-order-recurrence-splce
if the FOR is only used in the exit or as scalar ph resume value.
2024-06-08 21:40:30 +01:00
Florian Hahn
a43d999d14
[VPlan] Check if only first part is used for all per-part VPInsts.
Apply the onlyFirstPartUsed logic generally to all per-part
VPInstructions. Note that the test changes remove the second part
of an unsued first-order recurrence splice.
2024-06-08 20:31:54 +01:00
Florian Hahn
05e1b5340b
[VPlan] Model FOR resume value extraction in VPlan. (#93396)
This patch uses the ExtractFromEnd VPInstruction opcode
to extract the value of a FOR to be used as resume value for the ph in
the scalar loop.

It adds a new live-out that temporarily wraps the FOR phi in the scalar
loop. fixFixedOrderRecurrence will process live outs for fixed order
recurrence phis by creating a new phi node in the scalar preheader, 
using the generated value for the live-out as incoming value from the
middle block and the original start value as incoming value for the
other edge. Creation of the phi in the preheader, as well as updating
the phi in the scalar loop will also be moved to VPlan in the future,
eventually retiring fixFixedOrderRecurrence

Depends on https://github.com/llvm/llvm-project/pull/93395

PR: https://github.com/llvm/llvm-project/pull/93396
2024-06-05 11:18:06 +01:00
Florian Hahn
f18536d642
[VPlan] Model address separately. (#72164)
Move vector pointer generation to a separate VPVectorPointerRecipe.
This untangles address computation from the memory recipes future
and is also needed to enable explicit unrolling in VPlan.

https://github.com/llvm/llvm-project/pull/72164
2024-01-01 19:51:15 +00:00
Florian Hahn
8f781b96e2
Revert "[VPlan] Mark recurrence recipes as not having side-effects."
This reverts commit 02369b75fdd7b5fc5d9b47f1b60587c225918511.

At the moment, live-outs used *only* for the resume values in the scalar
loop are not modeled in VPlan yet. This means first-order recurrence
recipes could be removed, when a scalar epilogue is required and the
only use of a FOR is outside the loop.

Keep treating recurrence recipes as having side-effects for now, to
avoid them being removed.

Fixes #62954.
2023-06-06 11:35:26 +02:00
Florian Hahn
f47084ecfb
[LV] Use force-vector-width for X86 recurrence test.
This makes sure that all tests that can be vectorized in the file are
vectorized.
2023-06-06 11:27:35 +02:00
Florian Hahn
4c51a45e80
[LV] Add test for #62954. 2023-06-06 11:20:22 +02:00
Florian Hahn
35af27c30a
[VPlan] Only create extracts for recurrence exits if there are live-outs.
Move the code to collect live-out earlier and only generate extracts for
exit values if there are any live-outs that use them.

Depends on D147472.

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D147567
2023-04-10 21:08:34 +01:00
Roman Lebedev
be51fa4580
[NFC] Port all runlines for LoopVectorize pass tests to -passes syntax 2022-12-05 22:17:30 +03:00
David Green
e29f9f7572 [AArch64][X86] Add some fixed-order-recurrence tests to check the costmodel of fixed order recurrences. NFC 2022-08-24 08:18:01 +01:00