message: Add an initial placeholder for IPU specific session config options
diff: @@ -131,6 +131,12 @@ message GPUOptions {
  Experimental experimental = 9;
  };
  +message IPUOptions {
  + // When set to true, use mixed 16:32 bit arithmetic for 16 bit operations
  + bool use_32_bit_accumulation = 1;
  +
  +};
  +
  // Options passed to the graph optimizer
  message OptimizerOptions {
  // If true, optimize the graph using common subexpression elimination.
  @@ -359,7 +365,10 @@ message ConfigProto {
  // shared with other sessions.
  bool isolate_session_state = 15;
  - // Next: 16
  + // Options that apply to Graphcore IPUs
  + IPUOptions ipu_options = 16;
  +
  + // Next: 17
  };
  // Options for a single Run() call.
  