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#include <stdint.h>
#include <stdio.h>
#include <arm_sve.h>

#include "common.h"

#ifdef DOUBLE
#define COUNT "cntd"
#define SV_TYPE svfloat64_t
#define SV_INDEX svuint64_t
#define SV_INDEXER svindex_u64
#define SV_TRUE svptrue_b64
#define SV_WHILE svwhilelt_b64
#define SV_PREFETCH svprfd_gather_index
#else
#define COUNT "cntw"
#define SV_TYPE svfloat32_t
#define SV_INDEX svuint32_t
#define SV_INDEXER svindex_u32
#define SV_TRUE svptrue_b32
#define SV_WHILE svwhilelt_b32
#define SV_PREFETCH svprfw_gather_index
#endif

#define INNER_COPY(pg, a_offset_inner, b_offset, lda, active)   \
    a_vec = svld1_gather_index(pg, a_offset_inner, lda_vec);    \
    svst1(pg, b_offset, a_vec);                                 \
    a_offset_inner++;                                           \
    b_offset += active;

int CNAME(BLASLONG m, BLASLONG n, IFLOAT *a, BLASLONG lda, IFLOAT *b) {
    uint64_t sve_size;
    asm(COUNT" %[SIZE_]" : [SIZE_]  "=r" (sve_size) : : );

    IFLOAT *a_offset, *a_offset_inner, *b_offset;
    a_offset = a;
    b_offset = b;

    SV_INDEX lda_vec = SV_INDEXER(0LL, lda);
    SV_TYPE a_vec;
    svbool_t pg_true = SV_TRUE();

    BLASLONG single_vectors_n = n & -sve_size;
    for (BLASLONG j = 0; j < single_vectors_n; j += sve_size) {
        a_offset_inner = a_offset;

        svbool_t pg = pg_true;
        uint64_t active = sve_size;
        uint64_t i_cnt = m >> 3;
        while (i_cnt--) {
            INNER_COPY(pg, a_offset_inner, b_offset, lda, active);
            INNER_COPY(pg, a_offset_inner, b_offset, lda, active);
            INNER_COPY(pg, a_offset_inner, b_offset, lda, active);
            INNER_COPY(pg, a_offset_inner, b_offset, lda, active);
            INNER_COPY(pg, a_offset_inner, b_offset, lda, active);
            INNER_COPY(pg, a_offset_inner, b_offset, lda, active);
            INNER_COPY(pg, a_offset_inner, b_offset, lda, active);
            INNER_COPY(pg, a_offset_inner, b_offset, lda, active);
        }

        if (m & 4) {
            INNER_COPY(pg, a_offset_inner, b_offset, lda, active);
            INNER_COPY(pg, a_offset_inner, b_offset, lda, active);
            INNER_COPY(pg, a_offset_inner, b_offset, lda, active);
            INNER_COPY(pg, a_offset_inner, b_offset, lda, active);
        }

        if (m & 2) {
            INNER_COPY(pg, a_offset_inner, b_offset, lda, active);
            INNER_COPY(pg, a_offset_inner, b_offset, lda, active);
        }

        if (m & 1) {
            INNER_COPY(pg, a_offset_inner, b_offset, lda, active);
        }

        a_offset += sve_size * lda;
    }

    BLASLONG remaining_n = n - single_vectors_n;
    if (remaining_n) {
        a_offset_inner = a_offset;
        svbool_t pg = SV_WHILE((uint64_t)0L, (uint64_t)remaining_n);
        uint64_t active = remaining_n;
        uint64_t i_cnt = m >> 2;
        while (i_cnt--) {
            INNER_COPY(pg, a_offset_inner, b_offset, lda, active);
            INNER_COPY(pg, a_offset_inner, b_offset, lda, active);
            INNER_COPY(pg, a_offset_inner, b_offset, lda, active);
            INNER_COPY(pg, a_offset_inner, b_offset, lda, active);
        }

        if (m & 2) {
            INNER_COPY(pg, a_offset_inner, b_offset, lda, active);
            INNER_COPY(pg, a_offset_inner, b_offset, lda, active);
        }

        if (m & 1) {
            INNER_COPY(pg, a_offset_inner, b_offset, lda, active);
        }
    }

    return 0;
}
