anchor.diff:     let segmenterFsm <- mkAutoFSM(seq
         while (True) seq
   	 action
  -	    let command <- toGet(ioCommandFifo).get();
  -	    ioIterator.start(IteratorConfig {xbase: 0,
  -					     xlimit: command.numBlocks,
  -					     xstep: `BlocksPerRequest},
  -			     command);
  -	    commandStartProbe <= command.startBlock;
  -	    commandNumBlocksProbe <= command.numBlocks;
  +	    NvmeIoCommand command = unpack(0);
  +	    Bit#(1) commandSource = 0;
  +	    Bool commandValid = False;
  +	    if (ioCommandFifo.notEmpty) begin
  +	       command <- toGet(ioCommandFifo).get();
  +	       commandValid = True;
  +	       commandSource = 0;
  +	    end
  +`ifdef NVME_ACCELERATOR_INTERFACE
  +	    else if (ioCommandFifoAccel.notEmpty) begin
  +	       command <- toGet(ioCommandFifoAccel).get();
  +	       commandValid = True;
  +	       commandSource = 1;
  +	    end
  +`endif
  +	    if (commandValid) begin
  +	       ioIterator.start(IteratorConfig {xbase: 0,
  +						xlimit: command.numBlocks,
  +						xstep: `BlocksPerRequest},
  +				command);
  +	       commandStartProbe <= command.startBlock;
  +	       commandNumBlocksProbe <= command.numBlocks;
  +	       ioCommandSourceFifo.enq(commandSource);
  +	    end
   	 endaction
            while (ioIterator.ivpipe.notEmpty()) seq
   	    action
  
positive.code: 	       let command = v.ctxt;
  	       if (v.last) begin
  		  command.numBlocks = command.numBlocks - v.value; //fixme
  	       end
  	       else begin
  		  command.numBlocks = `BlocksPerRequest;
  	       end
  	       command.startBlock = command.startBlock + extend(v.value);
  	       ioSegmentFifo.enq(command);
  
  	       segmentStartProbe <= truncate(command.startBlock) + v.value;
  	       segmentNumBlocksProbe <= command.numBlocks;
  
negative.code:       while (True) seq
  	 action
  	    let req <- toGet(ioSegmentFifo).get();
  	    let source <- toGet(ioSegmentSourceFifo).get();
  	    Vector#(16,Bit#(32)) command = unpack(0);
  	    command[0] = { requestId, req.flags, req.opcode };
  	    command[1] = 1; // nsid
  