node_stage.h

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/***************************************************************************************
 * File         : node_stage.h
 * Author       : HPS Research Group
 * Date         : 1/28/1999
 * Description  :
 ***************************************************************************************/

#ifndef __NODE_STAGE_H__
#define __NODE_STAGE_H__

#include "exec_stage.h"
#include "stage_data.h"


/**************************************************************************************/
// Types

typedef struct Reservation_Station_struct {
  uns  proc_id;
  char name[EXEC_PORTS_MAX_NAME_LEN];  // unique name of the RS, from
                                       // exec_ports.def
  uns32       size;                    // 0 is infinite
  Func_Unit** connected_fus;  // FUs that this reservation station is connected
                              // to.
  uns32 num_fus;              // number of fus that this rs is connected to.
  uns32 rs_op_count;          // number of ops in this reservation station
} Reservation_Station;

typedef struct Node_Stage_struct {
  uns        proc_id;
  Stage_Data sd;  // stage interface data

  Op*   node_head;   // linked-list of ops in the node stage
  Op*   node_tail;   // linked-list of ops in the node stage
  int32 node_count;  // number of ops in the node table

  Op* rdy_head;  // linked-list of ops that are ready to schedule. Ops
                 // are put in here when they are issued, or after they
                 // are issued and another op wakes them up.

  Counter ret_op;  // next op number to retire

  Counter last_scheduled_opnum;  // opnum of the last scheduled op

  Op* next_op_into_rs;      // oldest issued op not yet in the scheduling window
                            // (RS)
  Reservation_Station* rs;  // information about all of the reservation stations

  Flag mem_blocked;       // are we out of mem req buffers for this core
  uns  mem_block_length;  // length of the current memory block
  uns  ret_stall_length;  // length of the current retirement stall
} Node_Stage;


/**************************************************************************************/
// External Variables

extern Node_Stage* node;


/**************************************************************************************/
// Prototypes

void set_node_stage(Node_Stage*);
void init_node_stage(uns8, const char*);
void reset_node_stage(void);
void reset_all_ops_node_stage(void);
void recover_node_stage(void);
void debug_node_stage(void);
void update_node_stage(Stage_Data*);
Flag is_node_stage_stalled(void);

void  node_sched_ops(void);
void  node_handle_scheduled_ops(void);
void  node_issue(Stage_Data*);
void  node_fill_rs(void);
void  node_retire(void);
void  check_if_mem_blocked(void);
void  oldest_first_sched(Op*);
int64 find_emptiest_rs(Op*);

/**************************************************************************************/

#endif /* #ifndef __NODE_STAGE_H__ */