This patch removes CondBit and Predicate from VPBasicBlock. To do so,
the patch introduces a new branch-on-cond VPInstruction opcode to model
a branch on a condition explicitly.
This addresses a long-standing TODO/FIXME that blocks shouldn't be users
of VPValues. Those extra users can cause issues for VPValue-based
analyses that don't expect blocks. Addressing this fixme should allow us
to re-introduce 266ea446ab7476.
The generic branch opcode can also be used in follow-up patches.
Depends on D123005.
Reviewed By: Ayal
Differential Revision: https://reviews.llvm.org/D126618
This patch updates the VPlan native path to use VPRegionBlocks for all
loops in a loop nest. Up to now, only the outermost loop used a region.
This is a step towards unifying both paths and keep things consistent
between them. It also prepares various code-gen parts for modeling the
pre-header in the inner loop vectorizer (D121624).
Reviewed By: Ayal
Differential Revision: https://reviews.llvm.org/D123005
