[all-commits] [llvm/llvm-project] 4732b0: [mlir][dataflow] Remove early exit in dead code an...

[Jacob Mai Peng via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 4732b0cbc0ab123479084184305fb2873e221780
      https://github.com/llvm/llvm-project/commit/4732b0cbc0ab123479084184305fb2873e221780
  Author: Jacob Mai Peng <jacobmpeng at gmail.com>
  Date:   2023-10-05 (Thu, 05 Oct 2023)

  Changed paths:
    M mlir/lib/Analysis/DataFlow/DeadCodeAnalysis.cpp
    M mlir/test/Analysis/DataFlow/test-dead-code-analysis.mlir
    M mlir/test/Analysis/DataFlow/test-last-modified-callgraph.mlir

  Log Message:
  -----------
  [mlir][dataflow] Remove early exit in dead code analysis for zero-operand returns (#68151)

The PredecessorState in dead code analysis does not register
zero-operand returns as predecessors of their corresponding call ops.
This causes bugs with dense dataflow analyses that use dead code
analysis to query for the predecessors of CallOpInterfaces.

This was reasonable for sparse analyses, but isn't for dense ones.