2 Commits

Author SHA1 Message Date
Gil Rapaport
c07df42b1a [LV] Introduce VPBlendRecipe, VPWidenMemoryInstructionRecipe
This patch is part of D38676.

The patch introduces two new Recipes to handle instructions whose vectorization
involves masking. These Recipes take VPlan-level masks in D38676, but still rely
on ILV's existing createEdgeMask(), createBlockInMask() in this patch.

VPBlendRecipe handles intra-loop phi nodes, which are vectorized as a sequence
of SELECTs. Its execute() code is refactored out of ILV::widenPHIInstruction(),
which now handles only loop-header phi nodes.

VPWidenMemoryInstructionRecipe handles load/store which are to be widened
(but are not part of an Interleave Group). In this patch it simply calls
ILV::vectorizeMemoryInstruction on execute().

Differential Revision: https://reviews.llvm.org/D39068


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@318149 91177308-0d34-0410-b5e6-96231b3b80d8
2017-11-14 12:09:30 +00:00
Matthew Simpson
b6b20e1aa2 [LV] Scalarize operands of predicated instructions
This patch attempts to scalarize the operand expressions of predicated
instructions if they were conditionally executed in the original loop. After
scalarization, the expressions will be sunk inside the blocks created for the
predicated instructions. The transformation essentially performs
un-if-conversion on the operands.

The cost model has been updated to determine if scalarization is profitable. It
compares the cost of a vectorized instruction, assuming it will be
if-converted, to the cost of the scalarized instruction, assuming that the
instructions corresponding to each vector lane will be sunk inside a predicated
block, possibly avoiding execution. If it's more profitable to scalarize the
entire expression tree feeding the predicated instruction, the expression will
be scalarized; otherwise, it will be vectorized. We only consider the cost of
the entire expression to accurately estimate the cost of the required
insertelement and extractelement instructions.

Differential Revision: https://reviews.llvm.org/D26083

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@288909 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-07 15:03:32 +00:00