llvm-project.git/llvm/test/Transforms/LoopVectorize/vector-loop-backedge-elimination.ll, branch users/nico/python-2

[VPlan] Use InstSimplifyFolder instead of TargetFolder (#141222)

2025-05-28T09:00:14+00:00

For more powerful folding with operands that are not necessarily
all-constant, use InstSimplifyFolder instead of TargetFolder in
tryToConstantFold, and rename the function tryToFoldLiveIns.

[VPlan] Add initial CFG simplification, removing BranchOnCond true. (#106748)

2025-04-04T14:44:26+00:00

Add an initial CFG simplification transform, which removes the dead
edges for blocks terminated with BranchOnCond true.

At the moment, this removes the edge between middle block and scalar
preheader when folding the tail.

PR: https://github.com/llvm/llvm-project/pull/106748

[VPlan] Remove no-op SCALAR-STEPS after unrolling. (#123655)

2025-03-25T12:57:24+00:00

After unrolling, there may be additional simplifications that can be
applied. One example is removing SCALAR-STEPS for the first part where
only the first lane is demanded.

This removes redundant adds of 0 from a large number of tests (~200),
many which I am still working on updating.

In preparation for removing redundant WideIV steps added in
https://github.com/llvm/llvm-project/pull/119284.

PR: https://github.com/llvm/llvm-project/pull/123655

[VPlan] Also materialize broadcasts for backedge-taken-counts (NFC).

2025-03-18T22:35:18+00:00

Also include VPlan's BTC in the set of VPValues to materialize
broadcasts for, if it is used.

[VPlan] Handle VPExpandSCEVRecipe in isUniformAfterVectorization.

2025-01-07T21:35:09+00:00

VPExpandSCEVRecipes must be placed in the entry and are alway uniform.
This fixes a crash by always identifying them as uniform, even if the
main vector loop region has been removed.

Fixes https://github.com/llvm/llvm-project/issues/121897.

[VPlan] Remove loop region in optimizeForVFAndUF. (#108378)

2025-01-05T15:50:42+00:00

Update optimizeForVFAndUF to completely remove the vector loop region
when possible. At the moment, we cannot remove the region if it contains

* widened IVs: the recipe is needed to generate the step vector
* reductions: ComputeReductionResults requires the reduction phi recipe
for codegen.

Both cases can be addressed by more explicit modeling.

The patch also includes a number of updates to allow executing VPlans
without a vector loop region.

Depends on https://github.com/llvm/llvm-project/pull/110004

[LV] Also verify loops in vector loop removal tests.

2024-12-31T20:11:23+00:00

Also verify loop info in tests added in 7d6ec3b9680.

[LV] Add more tests for vector loop removal.

2024-12-31T20:08:54+00:00

Add missing test coverage of loops where the vector loop region can be
removed that include replicate recipes as well as nested loops.

Extra test coverage for https://github.com/llvm/llvm-project/pull/108378.

[LV] Use SCEV to check if the trip count <= VF * UF.

2022-12-24T18:34:54+00:00

Just comparing constant trip counts causes LV to miss cases where the
vector loop body only executes once.

The motivation for this is to remove the need for unrolling to remove
vector loop back-edges, if the body only executes once in more cases.

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D133017

[LV] Add test case where SCEV is needed to remove vector backedge.

2022-08-31T13:01:42+00:00

Test case mentioned in the discussion for D115261.