rte_lpm_altivec.h

/*
 * SPDX-License-Identifier: BSD-3-Clause
 * Copyright (C) IBM Corporation 2016.
 */

#ifndef _RTE_LPM_ALTIVEC_H_
#define _RTE_LPM_ALTIVEC_H_

#include <rte_branch_prediction.h>
#include <rte_byteorder.h>
#include <rte_common.h>
#include <rte_vect.h>

#ifdef __cplusplus
extern "C" {
#endif

static inline void
rte_lpm_lookupx4(const struct rte_lpm *lpm, xmm_t ip, uint32_t hop[4],
    uint32_t defv)
{
    vector signed int i24;
    rte_xmm_t i8;
    uint32_t tbl[4];
    uint64_t idx, pt, pt2;
    const uint32_t *ptbl;

    const uint32_t mask = UINT8_MAX;
    const vector signed int mask8 = (xmm_t){mask, mask, mask, mask};

    /*
     * RTE_LPM_VALID_EXT_ENTRY_BITMASK for 2 LPM entries
     * as one 64-bit value (0x0300000003000000).
     */
    const uint64_t mask_xv =
        ((uint64_t)RTE_LPM_VALID_EXT_ENTRY_BITMASK |
        (uint64_t)RTE_LPM_VALID_EXT_ENTRY_BITMASK << 32);

    /*
     * RTE_LPM_LOOKUP_SUCCESS for 2 LPM entries
     * as one 64-bit value (0x0100000001000000).
     */
    const uint64_t mask_v =
        ((uint64_t)RTE_LPM_LOOKUP_SUCCESS |
        (uint64_t)RTE_LPM_LOOKUP_SUCCESS << 32);

    /* get 4 indexes for tbl24[]. */
    i24 = vec_sr((xmm_t) ip,
        (vector unsigned int){CHAR_BIT, CHAR_BIT, CHAR_BIT, CHAR_BIT});

    /* extract values from tbl24[] */
    idx = (uint32_t)i24[0];
    idx = idx < (1<<24) ? idx : (1<<24)-1;
    ptbl = (const uint32_t *)&lpm->tbl24[idx];
    tbl[0] = *ptbl;

    idx = (uint32_t) i24[1];
    idx = idx < (1<<24) ? idx : (1<<24)-1;
    ptbl = (const uint32_t *)&lpm->tbl24[idx];
    tbl[1] = *ptbl;

    idx = (uint32_t) i24[2];
    idx = idx < (1<<24) ? idx : (1<<24)-1;
    ptbl = (const uint32_t *)&lpm->tbl24[idx];
    tbl[2] = *ptbl;

    idx = (uint32_t) i24[3];
    idx = idx < (1<<24) ? idx : (1<<24)-1;
    ptbl = (const uint32_t *)&lpm->tbl24[idx];
    tbl[3] = *ptbl;

    /* get 4 indexes for tbl8[]. */
    i8.x = vec_and(ip, mask8);

    pt = (uint64_t)tbl[0] |
        (uint64_t)tbl[1] << 32;
    pt2 = (uint64_t)tbl[2] |
        (uint64_t)tbl[3] << 32;

    /* search successfully finished for all 4 IP addresses. */
    if (likely((pt & mask_xv) == mask_v) &&
            likely((pt2 & mask_xv) == mask_v)) {
        *(uint64_t *)hop = pt & RTE_LPM_MASKX4_RES;
        *(uint64_t *)(hop + 2) = pt2 & RTE_LPM_MASKX4_RES;
        return;
    }

    if (unlikely((pt & RTE_LPM_VALID_EXT_ENTRY_BITMASK) ==
            RTE_LPM_VALID_EXT_ENTRY_BITMASK)) {
        i8.u32[0] = i8.u32[0] +
            (uint8_t)tbl[0] * RTE_LPM_TBL8_GROUP_NUM_ENTRIES;
        ptbl = (const uint32_t *)&lpm->tbl8[i8.u32[0]];
        tbl[0] = *ptbl;
    }
    if (unlikely((pt >> 32 & RTE_LPM_VALID_EXT_ENTRY_BITMASK) ==
            RTE_LPM_VALID_EXT_ENTRY_BITMASK)) {
        i8.u32[1] = i8.u32[1] +
            (uint8_t)tbl[1] * RTE_LPM_TBL8_GROUP_NUM_ENTRIES;
        ptbl = (const uint32_t *)&lpm->tbl8[i8.u32[1]];
        tbl[1] = *ptbl;
    }
    if (unlikely((pt2 & RTE_LPM_VALID_EXT_ENTRY_BITMASK) ==
            RTE_LPM_VALID_EXT_ENTRY_BITMASK)) {
        i8.u32[2] = i8.u32[2] +
            (uint8_t)tbl[2] * RTE_LPM_TBL8_GROUP_NUM_ENTRIES;
        ptbl = (const uint32_t *)&lpm->tbl8[i8.u32[2]];
        tbl[2] = *ptbl;
    }
    if (unlikely((pt2 >> 32 & RTE_LPM_VALID_EXT_ENTRY_BITMASK) ==
            RTE_LPM_VALID_EXT_ENTRY_BITMASK)) {
        i8.u32[3] = i8.u32[3] +
            (uint8_t)tbl[3] * RTE_LPM_TBL8_GROUP_NUM_ENTRIES;
        ptbl = (const uint32_t *)&lpm->tbl8[i8.u32[3]];
        tbl[3] = *ptbl;
    }

    hop[0] = (tbl[0] & RTE_LPM_LOOKUP_SUCCESS) ? tbl[0] & 0x00FFFFFF : defv;
    hop[1] = (tbl[1] & RTE_LPM_LOOKUP_SUCCESS) ? tbl[1] & 0x00FFFFFF : defv;
    hop[2] = (tbl[2] & RTE_LPM_LOOKUP_SUCCESS) ? tbl[2] & 0x00FFFFFF : defv;
    hop[3] = (tbl[3] & RTE_LPM_LOOKUP_SUCCESS) ? tbl[3] & 0x00FFFFFF : defv;
}

#ifdef __cplusplus
}
#endif

#endif /* _RTE_LPM_ALTIVEC_H_ */