message: Use HloPtrComparator for routes map in InplaceFinder
  Summary: Ref T28597.
  Test Plan: All tests pass.
  Reviewers: #tensorflow, #framework_ip_review_-_any_oss_or_third-party_code_use_has_been_approved, georgep
  Maniphest Tasks: T28597
diff: @@ -16,6 +16,8 @@ limitations under the License.
  #ifndef TENSORFLOW_COMPILER_PLUGIN_POPLAR_DRIVER_PASSES_INPLACE_FINDER_H_
  #define TENSORFLOW_COMPILER_PLUGIN_POPLAR_DRIVER_PASSES_INPLACE_FINDER_H_
  +#include <map>
  +#include <vector>
  #include "tensorflow/compiler/plugin/poplar/driver/tools/inplace_util.h"
  #include "tensorflow/compiler/xla/service/hlo_pass_interface.h"
  @@ -48,7 +50,7 @@ class InplaceFinder : public HloModulePass {
  private:
  void RouteFinder(HloInstruction* inst, const std::vector<int64>&);
  - std::multimap<HloInstruction*, InplaceRoute> routes;
  + std::multimap<HloInstruction*, InplaceRoute, HloPtrComparator> routes;
  InplaceRoute current_route;
  