legalize-for-export.mlir 1.05 KB
// RUN: mlir-opt -llvm-legalize-for-export %s | FileCheck %s

// Verifies that duplicate successor with different arguments are deduplicated
// by introducing a new block that forwards its arguments to the original
// successor through an unconditional branch.
// CHECK-LABEL: @repeated_successor_different_args
llvm.func @repeated_successor_different_args(%arg0: !llvm.i1, %arg1: !llvm.i32, %arg2: !llvm.i32) {
  // CHECK: llvm.cond_br %{{.*}}, ^[[BB1:.*]]({{.*}}), ^[[BB2:.*]]({{.*}})
  llvm.cond_br %arg0, ^bb1(%arg1: !llvm.i32), ^bb1(%arg2: !llvm.i32)

// CHECK: ^[[BB1]]({{.*}}):
^bb1(%arg3: !llvm.i32):
  llvm.return

// CHECK: ^[[BB2]](%[[ARG:.*]]: !llvm.i32):
// CHECK:  llvm.br ^[[BB1]](%[[ARG]] : !llvm.i32)
}

// Verifies that duplicate successors without arguments do not lead to the
// introduction of new blocks during legalization.
// CHECK-LABEL: @repeated_successor_no_args
llvm.func @repeated_successor_no_args(%arg0: !llvm.i1) {
  // CHECK: llvm.cond_br
  llvm.cond_br %arg0, ^bb1, ^bb1

// CHECK: ^{{.*}}:
^bb1:
  llvm.return

// CHECK-NOT: ^{{.*}}:
}