[all-commits] [llvm/llvm-project] 94049d: [RISCV] Make computeIncomingVLVTYPE more conservat...

[Craig Topper via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 94049db913af32c5dfd8a09d0ba100f070363bdf
      https://github.com/llvm/llvm-project/commit/94049db913af32c5dfd8a09d0ba100f070363bdf
  Author: Craig Topper <craig.topper at sifive.com>
  Date:   2022-09-19 (Mon, 19 Sep 2022)

  Changed paths:
    M llvm/lib/Target/RISCV/RISCVInsertVSETVLI.cpp

  Log Message:
  -----------
  [RISCV] Make computeIncomingVLVTYPE more conservative when merging predecessor state.

If we have already calculated the incoming state before, use that
as our starting point to ensure we are conservative.

This fixes an infinite loop found in our downstream where we
we allowed two waves of updates to propagate through a loop and
the merge points allowed us to toggle back and forth between states.
No small reproducer right now.

Differential Revision: https://reviews.llvm.org/D134229