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Line 35... |
#include "stats.h"
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#include "stats.h"
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/* Branch prediction buffer */
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/* Branch prediction buffer */
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/* Length of BPB */
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/* Length of BPB */
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#define BPB_LEN 32
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#define BPB_LEN 128
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/* Number of BPB ways (1, 2, 3 etc.). */
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/* Number of BPB ways (1, 2, 3 etc.). */
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#define BPB_WAYS 2
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#define BPB_WAYS 1
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/* Number of prediction states (2, 4, 8 etc.). */
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/* Number of prediction states (2, 4, 8 etc.). */
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#define BPB_PSTATES 2
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#define BPB_PSTATES 2
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/* Number of usage states (2, 3, 4 etc.). */
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/* Number of usage states (2, 3, 4 etc.). */
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Line 57... |
not taken == 1, strongly not taken == 0 */
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not taken == 1, strongly not taken == 0 */
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int lru; /* least recently == 0 */
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int lru; /* least recently == 0 */
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} way[BPB_WAYS];
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} way[BPB_WAYS];
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} bpb[BPB_LEN];
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} bpb[BPB_LEN];
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void bpb_info()
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{
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printf("BPB %d bytes: ", BPB_LEN * BPB_WAYS * (BPB_PSTATES + BPB_USTATES) / 8);
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printf("%d ways, %d sets, %d bits/prediction\n", BPB_WAYS, BPB_LEN, BPB_PSTATES + BPB_USTATES);
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}
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/* First check if branch is already in the cache and if it is:
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/* First check if branch is already in the cache and if it is:
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- increment BPB hit stats,
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- increment BPB hit stats,
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- set 'lru' at this way to BPB_USTATES - 1 and
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- set 'lru' at this way to BPB_USTATES - 1 and
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decrement 'lru' of other ways unless they have reached 0,
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decrement 'lru' of other ways unless they have reached 0,
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- increment correct/incorrect stats according to BPB 'taken' field
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- increment correct/incorrect stats according to BPB 'taken' field
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Line 133... |
}
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}
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/* Branch target instruction cache */
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/* Branch target instruction cache */
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/* Length of BTIC */
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/* Length of BTIC */
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#define BTIC_LEN 32
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#define BTIC_LEN 128
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/* Number of BTIC ways (1, 2, 3 etc.). */
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/* Number of BTIC ways (1, 2, 3 etc.). */
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#define BTIC_WAYS 2
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#define BTIC_WAYS 2
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/* Number of usage states (2, 3, 4 etc.). */
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/* Number of usage states (2, 3, 4 etc.). */
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#define BTIC_USTATES 2
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#define BTIC_USTATES 2
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/* Target block size in bytes. */
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#define BTIC_BLOCKSIZE 4
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struct btic_entry {
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struct btic_entry {
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struct {
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struct {
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unsigned long addr; /* cached target address of a branch */
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unsigned long addr; /* cached target address of a branch */
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int lru; /* least recently used */
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int lru; /* least recently used */
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char *insn; /* cached insn at target address (not used currently) */
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char *insn; /* cached insn at target address (not used currently) */
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} way[BTIC_WAYS];
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} way[BTIC_WAYS];
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} btic[BTIC_LEN];
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} btic[BTIC_LEN];
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void btic_info()
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{
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printf("BTIC %d bytes: ", BTIC_LEN * BTIC_WAYS * (BTIC_USTATES + BTIC_BLOCKSIZE * 8) / 8);
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printf("%d ways, %d sets, %d bits/target\n", BTIC_WAYS, BTIC_LEN, BTIC_USTATES + BTIC_BLOCKSIZE * 8);
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}
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/* First check if target addr is already in the cache and if it is:
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/* First check if target addr is already in the cache and if it is:
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- increment BTIC hit stats,
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- increment BTIC hit stats,
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- set 'lru' at this way to BTIC_USTATES - 1 and
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- set 'lru' at this way to BTIC_USTATES - 1 and
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decrement 'lru' of other ways unless they have reached 0,
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decrement 'lru' of other ways unless they have reached 0,
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and if not:
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and if not:
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