branch.c

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#include "perf.h"
#include "util/util.h"
#include "util/debug.h"
#include "util/branch.h"

static bool cross_area(u64 addr1, u64 addr2, int size)
{
    u64 align1, align2;

    align1 = addr1 & ~(size - 1);
    align2 = addr2 & ~(size - 1);

    return (align1 != align2) ? true : false;
}

#define AREA_4K     4096
#define AREA_2M     (2 * 1024 * 1024)

void branch_type_count(struct branch_type_stat *st, struct branch_flags *flags,
               u64 from, u64 to)
{
    if (flags->type == PERF_BR_UNKNOWN || from == 0)
        return;

    st->counts[flags->type]++;

    if (flags->type == PERF_BR_COND) {
        if (to > from)
            st->cond_fwd++;
        else
            st->cond_bwd++;
    }

    if (cross_area(from, to, AREA_2M))
        st->cross_2m++;
    else if (cross_area(from, to, AREA_4K))
        st->cross_4k++;
}

const char *branch_type_name(int type)
{
    const char *branch_names[PERF_BR_MAX] = {
        "N/A",
        "COND",
        "UNCOND",
        "IND",
        "CALL",
        "IND_CALL",
        "RET",
        "SYSCALL",
        "SYSRET",
        "COND_CALL",
        "COND_RET"
    };

    if (type >= 0 && type < PERF_BR_MAX)
        return branch_names[type];

    return NULL;
}

void branch_type_stat_display(FILE *fp, struct branch_type_stat *st)
{
    u64 total = 0;
    int i;

    for (i = 0; i < PERF_BR_MAX; i++)
        total += st->counts[i];

    if (total == 0)
        return;

    fprintf(fp, "\n#");
    fprintf(fp, "\n# Branch Statistics:");
    fprintf(fp, "\n#");

    if (st->cond_fwd > 0) {
        fprintf(fp, "\n%8s: %5.1f%%",
            "COND_FWD",
            100.0 * (double)st->cond_fwd / (double)total);
    }

    if (st->cond_bwd > 0) {
        fprintf(fp, "\n%8s: %5.1f%%",
            "COND_BWD",
            100.0 * (double)st->cond_bwd / (double)total);
    }

    if (st->cross_4k > 0) {
        fprintf(fp, "\n%8s: %5.1f%%",
            "CROSS_4K",
            100.0 * (double)st->cross_4k / (double)total);
    }

    if (st->cross_2m > 0) {
        fprintf(fp, "\n%8s: %5.1f%%",
            "CROSS_2M",
            100.0 * (double)st->cross_2m / (double)total);
    }

    for (i = 0; i < PERF_BR_MAX; i++) {
        if (st->counts[i] > 0)
            fprintf(fp, "\n%8s: %5.1f%%",
                branch_type_name(i),
                100.0 *
                (double)st->counts[i] / (double)total);
    }
}

static int count_str_scnprintf(int idx, const char *str, char *bf, int size)
{
    return scnprintf(bf, size, "%s%s", (idx) ? " " : " (", str);
}

int branch_type_str(struct branch_type_stat *st, char *bf, int size)
{
    int i, j = 0, printed = 0;
    u64 total = 0;

    for (i = 0; i < PERF_BR_MAX; i++)
        total += st->counts[i];

    if (total == 0)
        return 0;

    if (st->cond_fwd > 0)
        printed += count_str_scnprintf(j++, "COND_FWD", bf + printed, size - printed);

    if (st->cond_bwd > 0)
        printed += count_str_scnprintf(j++, "COND_BWD", bf + printed, size - printed);

    for (i = 0; i < PERF_BR_MAX; i++) {
        if (i == PERF_BR_COND)
            continue;

        if (st->counts[i] > 0)
            printed += count_str_scnprintf(j++, branch_type_name(i), bf + printed, size - printed);
    }

    if (st->cross_4k > 0)
        printed += count_str_scnprintf(j++, "CROSS_4K", bf + printed, size - printed);

    if (st->cross_2m > 0)
        printed += count_str_scnprintf(j++, "CROSS_2M", bf + printed, size - printed);

    return printed;
}