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#include "common.h"

#if !defined(DOUBLE)
#define VSETVL(n)               __riscv_vsetvl_e32m2(n)
#define VSETVL_MAX              __riscv_vsetvlmax_e32m2()
#define FLOAT_V_T               vfloat32m2_t
#define FLOAT_VX2_T             vfloat32m2x2_t
#define VGET_VX2                __riscv_vget_v_f32m2x2_f32m2
#define VSET_VX2                __riscv_vset_v_f32m2_f32m2x2
#define VLEV_FLOAT              __riscv_vle32_v_f32m2
#define VSEV_FLOAT              __riscv_vse32_v_f32m2
#define VLSEG2_FLOAT            __riscv_vlseg2e32_v_f32m2x2
#define VSSEG2_FLOAT            __riscv_vsseg2e32_v_f32m2x2
#define VFMACCVF_FLOAT          __riscv_vfmacc_vf_f32m2
#define VFNMSACVF_FLOAT         __riscv_vfnmsac_vf_f32m2
#define VFMULVF_FLOAT           __riscv_vfmul_vf_f32m2
#else
#define VSETVL(n)               __riscv_vsetvl_e64m2(n)
#define VSETVL_MAX              __riscv_vsetvlmax_e64m2()
#define FLOAT_V_T               vfloat64m2_t
#define FLOAT_VX2_T             vfloat64m2x2_t
#define VGET_VX2                __riscv_vget_v_f64m2x2_f64m2
#define VSET_VX2                __riscv_vset_v_f64m2_f64m2x2
#define VLEV_FLOAT              __riscv_vle64_v_f64m2
#define VSEV_FLOAT              __riscv_vse64_v_f64m2
#define VLSEG2_FLOAT            __riscv_vlseg2e64_v_f64m2x2
#define VSSEG2_FLOAT            __riscv_vsseg2e64_v_f64m2x2
#define VFMVVF_FLOAT            __riscv_vfmv_v_f_f64m2
#define VFMACCVF_FLOAT          __riscv_vfmacc_vf_f64m2
#define VFNMSACVF_FLOAT         __riscv_vfnmsac_vf_f64m2
#define VFMULVF_FLOAT           __riscv_vfmul_vf_f64m2
#endif


static FLOAT dm1 = -1.;

#ifdef CONJ
#define GEMM_KERNEL   GEMM_KERNEL_R
#else
#define GEMM_KERNEL   GEMM_KERNEL_N
#endif

#if GEMM_DEFAULT_UNROLL_N == 1
#define GEMM_UNROLL_N_SHIFT 0
#endif

#if GEMM_DEFAULT_UNROLL_N == 2
#define GEMM_UNROLL_N_SHIFT 1
#endif

#if GEMM_DEFAULT_UNROLL_N == 4
#define GEMM_UNROLL_N_SHIFT 2
#endif

#if GEMM_DEFAULT_UNROLL_N == 8
#define GEMM_UNROLL_N_SHIFT 3
#endif

#if GEMM_DEFAULT_UNROLL_N == 16
#define GEMM_UNROLL_N_SHIFT 4
#endif

// Optimizes the implementation in ../arm64/trsm_kernel_RT_sve.c

#ifndef COMPLEX

static inline void solve(BLASLONG m, BLASLONG n, FLOAT *a, FLOAT *b, FLOAT *c, BLASLONG ldc) {

    FLOAT bb;
    FLOAT *pci, *pcj;

    int i, j, k;
    FLOAT_V_T va, vc;

    size_t vl;

    a += (n - 1) * m;
    b += (n - 1) * n;

    for (i = n - 1; i >= 0; i--) {

        bb = *(b + i);
        pci = c + i * ldc;
        pcj = c;
        for (j = m; j > 0; j -= vl) {
            vl = VSETVL(j);
            va = VLEV_FLOAT(pci, vl);
            va = VFMULVF_FLOAT(va, bb, vl);
            VSEV_FLOAT(a, va, vl);
            VSEV_FLOAT(pci, va, vl);
            a   += vl;
            pci += vl;
            for (k = 0; k < i; k ++){
                vc = VLEV_FLOAT(pcj + k * ldc, vl);
                vc = VFNMSACVF_FLOAT(vc, *(b + k), va, vl);
                VSEV_FLOAT(pcj + k * ldc, vc, vl);
            }
            pcj += vl;
        }
        b -= n;
        a -= 2 * m;
    }
}

#else

static inline void solve(BLASLONG m, BLASLONG n, FLOAT *a, FLOAT *b, FLOAT *c, BLASLONG ldc) {

    FLOAT bb1, bb2;

    FLOAT *pci, *pcj;

    int i, j, k;

    FLOAT_VX2_T vax2, vsx2, vcx2;
    FLOAT_V_T va1, va2, vs1, vs2, vc1, vc2;

    size_t vl;

    a += (n - 1) * m * 2;
    b += (n - 1) * n * 2;

    for (i = n - 1; i >= 0; i--) {

        bb1 = *(b + i * 2 + 0);
        bb2 = *(b + i * 2 + 1);

        pci = c + i * ldc * 2;
        pcj = c;
        for (j = m; j > 0; j -= vl) {
            vl = VSETVL(j);
            vax2 = VLSEG2_FLOAT(pci, vl);
            va1 = VGET_VX2(vax2, 0);
            va2 = VGET_VX2(vax2, 1);
#ifndef CONJ
            vs1 =   VFMULVF_FLOAT(va1, bb1, vl);
            vs1 = VFNMSACVF_FLOAT(vs1, bb2, va2, vl);
            vs2 =   VFMULVF_FLOAT(va1, bb2, vl);
            vs2 =  VFMACCVF_FLOAT(vs2, bb1, va2, vl);
#else
            vs1 =   VFMULVF_FLOAT(va1, bb1, vl);
            vs1 =  VFMACCVF_FLOAT(vs1, bb2, va2, vl);
            vs2 =   VFMULVF_FLOAT(va2, bb1, vl);
            vs2 = VFNMSACVF_FLOAT(vs2, bb2, va1, vl);
#endif
            vsx2 = VSET_VX2(vsx2, 0, vs1);
            vsx2 = VSET_VX2(vsx2, 1, vs2);
            VSSEG2_FLOAT(a, vsx2, vl);
            VSSEG2_FLOAT(pci, vsx2, vl);
            a += vl * 2;
            pci += vl * 2;

            for (k = 0; k < i; k ++){
                vcx2 = VLSEG2_FLOAT(pcj + k * ldc * 2, vl);
                vc1 = VGET_VX2(vcx2, 0);
                vc2 = VGET_VX2(vcx2, 1);
#ifndef CONJ
                vc1 =  VFMACCVF_FLOAT(vc1, *(b + k * 2 + 1), vs2, vl);
                vc1 = VFNMSACVF_FLOAT(vc1, *(b + k * 2 + 0), vs1, vl);
                vc2 = VFNMSACVF_FLOAT(vc2, *(b + k * 2 + 1), vs1, vl);
                vc2 = VFNMSACVF_FLOAT(vc2, *(b + k * 2 + 0), vs2, vl);
#else
                vc1 = VFNMSACVF_FLOAT(vc1, *(b + k * 2 + 0), vs1, vl);
                vc1 = VFNMSACVF_FLOAT(vc1, *(b + k * 2 + 1), vs2, vl);
                vc2 =  VFMACCVF_FLOAT(vc2, *(b + k * 2 + 1), vs1, vl);
                vc2 = VFNMSACVF_FLOAT(vc2, *(b + k * 2 + 0), vs2, vl);
#endif
                vcx2 = VSET_VX2(vcx2, 0, vc1);
                vcx2 = VSET_VX2(vcx2, 1, vc2);
                VSSEG2_FLOAT(pcj + k * ldc * 2, vcx2, vl);
            }
            pcj += vl * 2;
        }
        b -= n * 2;
        a -= 4 * m;
    }
}

#endif

int CNAME(BLASLONG m, BLASLONG n, BLASLONG k,  FLOAT dummy1,
#ifdef COMPLEX
    FLOAT dummy2,
#endif
    FLOAT *a, FLOAT *b, FLOAT *c, BLASLONG ldc, BLASLONG offset){

  BLASLONG i, j;
  FLOAT *aa, *cc;
  BLASLONG  kk;

  size_t vl = VSETVL_MAX;

    //fprintf(stderr, "%s , %s, m = %4ld  n = %4ld  k = %4ld offset = %4ld\n", __FILE__, __FUNCTION__, m, n, k, offset); // Debug

  kk = n - offset;
  c += n * ldc * COMPSIZE;
  b += n * k   * COMPSIZE;

  if (n & (GEMM_UNROLL_N - 1)) {

    j = 1;
    while (j < GEMM_UNROLL_N) {
      if (n & j) {

        aa  = a;
        b -= j * k  * COMPSIZE;
        c -= j * ldc* COMPSIZE;
        cc  = c;

        i = vl;
        if (i <= m) {

          do {
            if (k - kk > 0) {
              GEMM_KERNEL(vl, j, k - kk, dm1,
#ifdef COMPLEX
                  ZERO,
#endif
                  aa + vl * kk * COMPSIZE,
                  b  +  j            * kk * COMPSIZE,
                  cc,
                  ldc);
            }

            solve(vl, j,
                aa + (kk - j) * vl * COMPSIZE,
                b  + (kk - j) * j             * COMPSIZE,
                cc, ldc);

            aa += vl * k * COMPSIZE;
            cc += vl     * COMPSIZE;
            i += vl;
          } while (i <= m);
        }

        i = m % vl;
        if (i) {
          if (k - kk > 0) {
            GEMM_KERNEL(i, j, k - kk, dm1,
#ifdef COMPLEX
                ZERO,
#endif
                aa + i * kk * COMPSIZE,
                b  + j * kk * COMPSIZE,
                cc, ldc);
          }

          solve(i, j,
              aa + (kk - j) * i * COMPSIZE,
              b  + (kk - j) * j * COMPSIZE,
              cc, ldc);

          aa += i * k * COMPSIZE;
          cc += i     * COMPSIZE;

        }
        kk -= j;
      }
      j <<= 1;
    }
  }

  j = (n >> GEMM_UNROLL_N_SHIFT);

  if (j > 0) {

    do {
      aa  = a;
      b -= GEMM_UNROLL_N * k   * COMPSIZE;
      c -= GEMM_UNROLL_N * ldc * COMPSIZE;
      cc  = c;

      i = vl;
      if (i <= m) {
	do {
	  if (k - kk > 0) {
	    GEMM_KERNEL(vl, GEMM_UNROLL_N, k - kk, dm1,
#ifdef COMPLEX
			ZERO,
#endif
			aa + vl * kk * COMPSIZE,
			b  + GEMM_UNROLL_N * kk * COMPSIZE,
			cc,
			ldc);
	  }

	  solve(vl, GEMM_UNROLL_N,
		aa + (kk - GEMM_UNROLL_N) * vl * COMPSIZE,
		b  + (kk - GEMM_UNROLL_N) * GEMM_UNROLL_N * COMPSIZE,
		cc, ldc);

	  aa += vl * k * COMPSIZE;
	  cc += vl     * COMPSIZE;
	  i += vl;
	} while (i <= m);
      }

      i = m % vl;
      if (i) {
	    if (k - kk > 0) {
	      GEMM_KERNEL(i, GEMM_UNROLL_N, k - kk, dm1,
#ifdef COMPLEX
			  ZERO,
#endif
			  aa + i             * kk * COMPSIZE,
			  b  + GEMM_UNROLL_N * kk * COMPSIZE,
			  cc,
			  ldc);
	    }

	    solve(i, GEMM_UNROLL_N,
		  aa + (kk - GEMM_UNROLL_N) * i             * COMPSIZE,
		  b  + (kk - GEMM_UNROLL_N) * GEMM_UNROLL_N * COMPSIZE,
		  cc, ldc);

	    aa += i * k * COMPSIZE;
	    cc += i     * COMPSIZE;

      }

      kk -= GEMM_UNROLL_N;
      j --;
    } while (j > 0);
  }

  return 0;
}