Related issue: #159650

Description

mlir-opt --sccp crashes with an assertion failure in Block::getTerminator() when DeadCodeAnalysis::initializeRecursively walks into a function containing an acc.kernel_environment op that itself contains an acc.compute_region op. The isRegionOrCallableReturn helper calls block->getTerminator() on a block that mightHaveTerminator() returns true for but that has no terminator op, triggering the assertion.

Reproducer

module {
  func.func @fusion_bridge() -> index {
    %c = arith.constant 128 : index
    return %c : index
  }

  func.func @f(%data: memref<8xi32>) {
    acc.kernel_environment {
      acc.compute_region {
        acc.yield
      } {origin = "acc.parallel"}
    }
    return
  }

  %fusion_tmp = func.call @fusion_bridge() : () -> index
}

Command

mlir-opt --sccp --symbol-dce --cse --inline --canonicalize reproduce.mlir

Expected behavior

--sccp should process the file successfully or emit a diagnostic. DeadCodeAnalysis should not call getTerminator() on a block without first verifying it has a terminator, or isRegionOrCallableReturn should guard the getTerminator() call.

Actual behavior

mlir-opt: mlir/lib/IR/Block.cpp:250:
  Operation *mlir::Block::getTerminator():
  Assertion `mightHaveTerminator()' failed.
Aborted (core dumped)

Call chain

--sccp
  → DataFlowSolver::initializeAndRun
    → DeadCodeAnalysis::initialize
      → DeadCodeAnalysis::initializeRecursively
        → isRegionOrCallableReturn            (DeadCodeAnalysis.cpp:252)
          → Block::getTerminator()            (Block.cpp:250)
            ← assertion: mightHaveTerminator() failed