OpenBLAS/kernel/x86_64/dgemm_small_kernel_tn_skylakex.c

/***************************************************************************
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#include <immintrin.h>
#include "common.h"
#include <stdio.h>
#include <memory.h>

#define DECLARE_RESULT_512(M, N) __m512d result##M##N = _mm512_setzero_pd()
#define MATMUL_512(M, N) result##M##N = _mm512_fmadd_pd(Aval##M, Bval##N, result##M##N)

#define LOAD_KA_512(M, N) __m512d Aval##M = _mm512_loadu_pd(&A[(i + M)*lda + k]);
#define LOAD_KB_512(M, N) __m512d Bval##N = _mm512_loadu_pd(&B[(j + N)*ldb + k])
#define MASK_LOAD_KA_512(M, N) __m512d Aval##M = _mm512_maskz_loadu_pd(mask, &A[(i + M)*lda + k])
#define MASK_LOAD_KB_512(M, N) __m512d Bval##N = _mm512_maskz_loadu_pd(mask, &B[(j + N)*ldb + k])

#define REDUCE_4(rr0, rr1, rr2, rr3) \
	__m512d r0, r1, r2, r3, t0, t1, t2, t3;\
	r0 = _mm512_unpacklo_pd(rr0, rr1); r1 = _mm512_unpackhi_pd(rr0, rr1); \
	r2 = _mm512_unpacklo_pd(rr2, rr3); r3 = _mm512_unpackhi_pd(rr2, rr3); \
	t0 = _mm512_permutex2var_pd(r0, idx_lo, r2); t1 = _mm512_permutex2var_pd(r1, idx_lo, r3); \
	t2 = _mm512_permutex2var_pd(r0, idx_hi, r2); t3 = _mm512_permutex2var_pd(r1, idx_hi, r3); \
	r0 = _mm512_add_pd(t0, t1); r1 = _mm512_add_pd(t2, t3); t0 = _mm512_add_pd(r0, r1); \
	__m256d s0, s1; \
	s0 = _mm512_extractf64x4_pd(t0, 0); s1 = _mm512_extractf64x4_pd(t0, 1); \
	s0 = _mm256_add_pd(s0, s1); s0 = _mm256_mul_pd(alpha_256, s0);

#define REDUCE_M4(N) REDUCE_4(result0##N, result1##N, result2##N, result3##N)
#define REDUCE_N4(M) REDUCE_4(result##M##0, result##M##1, result##M##2, result##M##3)

#if defined(B0)
#define STORE_REDUCE(M, N) C[(j+N)*ldc + i + M] = alpha * _mm512_reduce_add_pd(result##M##N)
#define STORE_M4(N, s0) _mm256_storeu_pd(&C[(j + N)*ldc + i], s0);
#define STORE_N4(M, s0) _mm256_i64scatter_pd(&C[j*ldc + i + M], vindex_n, s0, 8);
#else
#define STORE_REDUCE(M, N) C[(j+N)*ldc + i + M] = alpha * _mm512_reduce_add_pd(result##M##N) + beta * C[(j+N)*ldc + i + M]
#define STORE_M4(N, s0) \
	asm("vfmadd231pd (%1), %2, %0": "+v"(s0):"r"(&C[(j + N)*ldc + i]), "v"(beta_256)); \
	_mm256_storeu_pd(&C[(j + N)*ldc + i], s0);

#define STORE_N4(M, s0) \
	s0 = _mm256_fmadd_pd(_mm256_i64gather_pd(&C[j*ldc + i + M], vindex_n, 8), beta_256, s0); \
	_mm256_i64scatter_pd(&C[j*ldc + i + M], vindex_n, s0, 8);
#endif
#define STORE_REDUCE_M4(N) {\
	REDUCE_M4(N) \
	STORE_M4(N, s0) \
}
#define STORE_REDUCE_N4(M) {\
	REDUCE_N4(M) \
	STORE_N4(M, s0) \
}


#if defined(B0)
int CNAME(BLASLONG M, BLASLONG N, BLASLONG K, FLOAT * A, BLASLONG lda, FLOAT alpha, FLOAT * B, BLASLONG ldb, FLOAT * C, BLASLONG ldc)
#else
int CNAME(BLASLONG M, BLASLONG N, BLASLONG K, FLOAT * A, BLASLONG lda, FLOAT alpha, FLOAT * B, BLASLONG ldb, FLOAT beta, FLOAT * C, BLASLONG ldc)
#endif
{
	// column major
	BLASLONG i, j, k;

	BLASLONG m4 = M & ~3;
	BLASLONG m2 = M & ~1;

	BLASLONG n4 = N & ~3;
	BLASLONG n2 = N & ~1;

	BLASLONG k8 = K & ~7;

	__mmask8 mask;

	__m256i vindex_n = _mm256_set_epi64x(ldc*3, ldc*2, ldc, 0);
	__m256d alpha_256 = _mm256_broadcast_sd(&alpha);
#if !defined(B0)
	__m256d beta_256 = _mm256_broadcast_sd(&beta);
#endif

	long long permute_table[] = {
		0, 1, 0|8, 1|8, 4, 5, 4|8, 5|8,
		2, 3, 2|8, 3|8, 6, 7, 6|8, 7|8,
	};
	__m512i idx_lo = _mm512_loadu_si512(permute_table);
	__m512i idx_hi = _mm512_loadu_si512(permute_table + 8);

	for (i = 0; i < m4; i += 4) {
		for (j = 0; j < n4; j += 4) {
			DECLARE_RESULT_512(0, 0); DECLARE_RESULT_512(1, 0); DECLARE_RESULT_512(2, 0); DECLARE_RESULT_512(3, 0);
			DECLARE_RESULT_512(0, 1); DECLARE_RESULT_512(1, 1); DECLARE_RESULT_512(2, 1); DECLARE_RESULT_512(3, 1);
			DECLARE_RESULT_512(0, 2); DECLARE_RESULT_512(1, 2); DECLARE_RESULT_512(2, 2); DECLARE_RESULT_512(3, 2);
			DECLARE_RESULT_512(0, 3); DECLARE_RESULT_512(1, 3); DECLARE_RESULT_512(2, 3); DECLARE_RESULT_512(3, 3);
			for (k = 0; k < k8; k += 8) {
				LOAD_KA_512(0, x); LOAD_KA_512(1, x); LOAD_KA_512(2, x); LOAD_KA_512(3, x);
				LOAD_KB_512(x, 0); LOAD_KB_512(x, 1); LOAD_KB_512(x, 2); LOAD_KB_512(x, 3);

				MATMUL_512(0, 0); MATMUL_512(1, 0); MATMUL_512(2, 0); MATMUL_512(3, 0);
				MATMUL_512(0, 1); MATMUL_512(1, 1); MATMUL_512(2, 1); MATMUL_512(3, 1);
				MATMUL_512(0, 2); MATMUL_512(1, 2); MATMUL_512(2, 2); MATMUL_512(3, 2);
				MATMUL_512(0, 3); MATMUL_512(1, 3); MATMUL_512(2, 3); MATMUL_512(3, 3);
			}
			int remains = K - k;
			if (remains) {
				mask = (1UL << remains) - 1;
				MASK_LOAD_KA_512(0, x); MASK_LOAD_KA_512(1, x); MASK_LOAD_KA_512(2, x); MASK_LOAD_KA_512(3, x);
				MASK_LOAD_KB_512(x, 0); MASK_LOAD_KB_512(x, 1); MASK_LOAD_KB_512(x, 2); MASK_LOAD_KB_512(x, 3);

				MATMUL_512(0, 0); MATMUL_512(1, 0); MATMUL_512(2, 0); MATMUL_512(3, 0);
				MATMUL_512(0, 1); MATMUL_512(1, 1); MATMUL_512(2, 1); MATMUL_512(3, 1);
				MATMUL_512(0, 2); MATMUL_512(1, 2); MATMUL_512(2, 2); MATMUL_512(3, 2);
				MATMUL_512(0, 3); MATMUL_512(1, 3); MATMUL_512(2, 3); MATMUL_512(3, 3);
			}
			STORE_REDUCE_M4(0); STORE_REDUCE_M4(1); STORE_REDUCE_M4(2); STORE_REDUCE_M4(3);
		}
		for (; j < n2; j += 2) {
			DECLARE_RESULT_512(0, 0); DECLARE_RESULT_512(1, 0); DECLARE_RESULT_512(2, 0); DECLARE_RESULT_512(3, 0);
			DECLARE_RESULT_512(0, 1); DECLARE_RESULT_512(1, 1); DECLARE_RESULT_512(2, 1); DECLARE_RESULT_512(3, 1);
			for (k = 0; k < k8; k += 8) {
				LOAD_KA_512(0, x); LOAD_KA_512(1, x); LOAD_KA_512(2, x); LOAD_KA_512(3, x);
				LOAD_KB_512(x, 0); LOAD_KB_512(x, 1);

				MATMUL_512(0, 0); MATMUL_512(1, 0); MATMUL_512(2, 0); MATMUL_512(3, 0);
				MATMUL_512(0, 1); MATMUL_512(1, 1); MATMUL_512(2, 1); MATMUL_512(3, 1);
			}
			int remains = K - k;
			if (remains) {
				mask = (1UL << remains) - 1;
				MASK_LOAD_KA_512(0, x); MASK_LOAD_KA_512(1, x); MASK_LOAD_KA_512(2, x); MASK_LOAD_KA_512(3, x);
				MASK_LOAD_KB_512(x, 0); MASK_LOAD_KB_512(x, 1);

				MATMUL_512(0, 0); MATMUL_512(1, 0); MATMUL_512(2, 0); MATMUL_512(3, 0);
				MATMUL_512(0, 1); MATMUL_512(1, 1); MATMUL_512(2, 1); MATMUL_512(3, 1);
			}
			STORE_REDUCE_M4(0); STORE_REDUCE_M4(1);
		}
		for (; j < N; j += 1) {
			DECLARE_RESULT_512(0, 0); DECLARE_RESULT_512(1, 0); DECLARE_RESULT_512(2, 0); DECLARE_RESULT_512(3, 0);
			for (k = 0; k < k8; k += 8) {
				LOAD_KA_512(0, x); LOAD_KA_512(1, x); LOAD_KA_512(2, x); LOAD_KA_512(3, x);
				LOAD_KB_512(x, 0);

				MATMUL_512(0, 0); MATMUL_512(1, 0); MATMUL_512(2, 0); MATMUL_512(3, 0);
			}
			int remains = K - k;
			if (remains) {
				mask = (1UL << remains) - 1;
				MASK_LOAD_KA_512(0, x); MASK_LOAD_KA_512(1, x); MASK_LOAD_KA_512(2, x); MASK_LOAD_KA_512(3, x);
				MASK_LOAD_KB_512(x, 0);

				MATMUL_512(0, 0); MATMUL_512(1, 0); MATMUL_512(2, 0); MATMUL_512(3, 0);
			}
			STORE_REDUCE_M4(0);
		}

	}
	for (; i < m2; i += 2) {
		for (j = 0; j < n4; j += 4) {
			DECLARE_RESULT_512(0, 0); DECLARE_RESULT_512(1, 0);
			DECLARE_RESULT_512(0, 1); DECLARE_RESULT_512(1, 1);
			DECLARE_RESULT_512(0, 2); DECLARE_RESULT_512(1, 2);
			DECLARE_RESULT_512(0, 3); DECLARE_RESULT_512(1, 3);
			for (k = 0; k < k8; k += 8) {
				LOAD_KA_512(0, x); LOAD_KA_512(1, x);
				LOAD_KB_512(x, 0); LOAD_KB_512(x, 1); LOAD_KB_512(x, 2); LOAD_KB_512(x, 3);

				MATMUL_512(0, 0); MATMUL_512(1, 0);
				MATMUL_512(0, 1); MATMUL_512(1, 1);
				MATMUL_512(0, 2); MATMUL_512(1, 2);
				MATMUL_512(0, 3); MATMUL_512(1, 3);
			}
			int remains = K - k;
			if (remains) {
				mask = (1UL << remains) - 1;
				MASK_LOAD_KA_512(0, x); MASK_LOAD_KA_512(1, x);
				MASK_LOAD_KB_512(x, 0); MASK_LOAD_KB_512(x, 1); MASK_LOAD_KB_512(x, 2); MASK_LOAD_KB_512(x, 3);

				MATMUL_512(0, 0); MATMUL_512(1, 0);
				MATMUL_512(0, 1); MATMUL_512(1, 1);
				MATMUL_512(0, 2); MATMUL_512(1, 2);
				MATMUL_512(0, 3); MATMUL_512(1, 3);
			}
			STORE_REDUCE_N4(0); STORE_REDUCE_N4(1);
		}
		for (; j < n2; j += 2) {
			DECLARE_RESULT_512(0, 0); DECLARE_RESULT_512(1, 0);
			DECLARE_RESULT_512(0, 1); DECLARE_RESULT_512(1, 1);
			for (k = 0; k < k8; k += 8) {
				LOAD_KA_512(0, x); LOAD_KA_512(1, x);
				LOAD_KB_512(x, 0); LOAD_KB_512(x, 1);

				MATMUL_512(0, 0); MATMUL_512(1, 0);
				MATMUL_512(0, 1); MATMUL_512(1, 1);
			}
			int remains = K - k;
			if (remains) {
				mask = (1UL << remains) - 1;
				MASK_LOAD_KA_512(0, x); MASK_LOAD_KA_512(1, x);
				MASK_LOAD_KB_512(x, 0); MASK_LOAD_KB_512(x, 1);

				MATMUL_512(0, 0); MATMUL_512(1, 0);
				MATMUL_512(0, 1); MATMUL_512(1, 1);
			}
			STORE_REDUCE(0, 0); STORE_REDUCE(1, 0);
			STORE_REDUCE(0, 1); STORE_REDUCE(1, 1);

		}
		for (; j < N; j += 1) {
			DECLARE_RESULT_512(0, 0); DECLARE_RESULT_512(1, 0);
			for (k = 0; k < k8; k += 8) {
				LOAD_KA_512(0, x); LOAD_KA_512(1, x);
				LOAD_KB_512(x, 0);

				MATMUL_512(0, 0); MATMUL_512(1, 0);
			}
			int remains = K - k;
			if (remains) {
				mask = (1UL << remains) - 1;
				MASK_LOAD_KA_512(0, x); MASK_LOAD_KA_512(1, x);
				MASK_LOAD_KB_512(x, 0);

				MATMUL_512(0, 0); MATMUL_512(1, 0);
			}
			STORE_REDUCE(0, 0); STORE_REDUCE(1, 0);
		}
	}
	for (; i < M; i += 1) {
		for (j = 0; j < n4; j += 4) {
			DECLARE_RESULT_512(0, 0);
			DECLARE_RESULT_512(0, 1);
			DECLARE_RESULT_512(0, 2);
			DECLARE_RESULT_512(0, 3);
			for (k = 0; k < k8; k += 8) {
				LOAD_KA_512(0, x);
				LOAD_KB_512(x, 0); LOAD_KB_512(x, 1); LOAD_KB_512(x, 2); LOAD_KB_512(x, 3);

				MATMUL_512(0, 0);
				MATMUL_512(0, 1);
				MATMUL_512(0, 2);
				MATMUL_512(0, 3);
			}
			int remains = K - k;
			if (remains) {
				mask = (1UL << remains) - 1;
				MASK_LOAD_KA_512(0, x);
				MASK_LOAD_KB_512(x, 0); MASK_LOAD_KB_512(x, 1); MASK_LOAD_KB_512(x, 2); MASK_LOAD_KB_512(x, 3);


				MATMUL_512(0, 0);
				MATMUL_512(0, 1);
				MATMUL_512(0, 2);
				MATMUL_512(0, 3);
			}
			STORE_REDUCE_N4(0);
		}
		for (; j < n2; j += 2) {
			DECLARE_RESULT_512(0, 0);
			DECLARE_RESULT_512(0, 1);
			for (k = 0; k < k8; k += 8) {
				LOAD_KA_512(0, x);
				LOAD_KB_512(x, 0); LOAD_KB_512(x, 1);

				MATMUL_512(0, 0);
				MATMUL_512(0, 1);
			}
			int remains = K - k;
			if (remains) {
				mask = (1UL << remains) - 1;
				MASK_LOAD_KA_512(0, x);
				MASK_LOAD_KB_512(x, 0); MASK_LOAD_KB_512(x, 1);

				MATMUL_512(0, 0);
				MATMUL_512(0, 1);
			}
			STORE_REDUCE(0, 0);
			STORE_REDUCE(0, 1);

		}
		for (; j < N; j += 1) {
			DECLARE_RESULT_512(0, 0);
			for (k = 0; k < k8; k += 8) {
				LOAD_KA_512(0, x);
				LOAD_KB_512(x, 0);

				MATMUL_512(0, 0);
			}
			int remains = K - k;
			if (remains) {
				mask = (1UL << remains) - 1;
				MASK_LOAD_KA_512(0, x);
				MASK_LOAD_KB_512(x, 0);

				MATMUL_512(0, 0);
			}
			STORE_REDUCE(0, 0);
		}
	}
	return 0;
}