--- /dev/null
+// This file is part of OpenCV project.
+// It is subject to the license terms in the LICENSE file found in the top-level directory
+// of this distribution and at http://opencv.org/license.html.
+//
+// Copyright (C) 2019, Intel Corporation, all rights reserved.
+#include "precomp.hpp"
+#include "sumpixels.hpp"
+
+namespace cv {
+namespace { // Anonymous namespace to avoid exposing the implementation classes
+
+//
+// NOTE: Look at the bottom of the file for the entry-point function for external callers
+//
+
+// At the moment only 3 channel support untilted is supported
+// More channel support coming soon.
+// TODO: Add support for sqsum and 1,2, and 4 channels
+class IntegralCalculator_3Channel {
+public:
+ IntegralCalculator_3Channel() {};
+
+
+ void calculate_integral_avx512(const uchar *src, size_t _srcstep,
+ double *sum, size_t _sumstep,
+ double *sqsum, size_t _sqsumstep,
+ int width, int height, int cn)
+ {
+ const int srcstep = (int)(_srcstep/sizeof(uchar));
+ const int sumstep = (int)(_sumstep/sizeof(double));
+ const int sqsumstep = (int)(_sqsumstep/sizeof(double));
+ const int ops_per_line = width * cn;
+
+ // Clear the first line of the sum as per spec (see integral documentation)
+ // Also adjust the index of sum and sqsum to be at the real 0th element
+ // and not point to the border pixel so it stays in sync with the src pointer
+ memset( sum, 0, (ops_per_line+cn)*sizeof(double));
+ sum += cn;
+
+ if (sqsum) {
+ memset( sqsum, 0, (ops_per_line+cn)*sizeof(double));
+ sqsum += cn;
+ }
+
+ // Now calculate the integral over the whole image one line at a time
+ for(int y = 0; y < height; y++) {
+ const uchar * src_line = &src[y*srcstep];
+ double * sum_above = &sum[y*sumstep];
+ double * sum_line = &sum_above[sumstep];
+ double * sqsum_above = (sqsum) ? &sqsum[y*sqsumstep] : NULL;
+ double * sqsum_line = (sqsum) ? &sqsum_above[sqsumstep] : NULL;
+
+ integral_line_3channel_avx512(src_line, sum_line, sum_above, sqsum_line, sqsum_above, ops_per_line);
+
+ }
+ }
+
+ static inline
+ void integral_line_3channel_avx512(const uchar *srcs,
+ double *sums, double *sums_above,
+ double *sqsums, double *sqsums_above,
+ int num_ops_in_line)
+ {
+ __m512i sum_accumulator = _mm512_setzero_si512(); // holds rolling sums for the line
+ __m512i sqsum_accumulator = _mm512_setzero_si512(); // holds rolling sqsums for the line
+
+ // The first element on each line must be zeroes as per spec (see integral documentation)
+ set_border_pixel_value(sums, sqsums);
+
+ // Do all 64 byte chunk operations then do the last bits that don't fit in a 64 byte chunk
+ aligned_integral( srcs, sums, sums_above, sqsums, sqsums_above, sum_accumulator, sqsum_accumulator, num_ops_in_line);
+ post_aligned_integral(srcs, sums, sums_above, sqsums, sqsums_above, sum_accumulator, sqsum_accumulator, num_ops_in_line);
+
+ }
+
+
+ static inline
+ void set_border_pixel_value(double *sums, double *sqsums)
+ {
+ // Sets the border pixel value to 0s.
+ // Note the hard coded -3 and the 0x7 mask is because we only support 3 channel right now
+ __m512i zeroes = _mm512_setzero_si512();
+
+ _mm512_mask_storeu_epi64(&sums[-3], 0x7, zeroes);
+ if (sqsums)
+ _mm512_mask_storeu_epi64(&sqsums[-3], 0x7, zeroes);
+ }
+
+
+ static inline
+ void aligned_integral(const uchar *&srcs,
+ double *&sums, double *&sums_above,
+ double *&sqsum, double *&sqsum_above,
+ __m512i &sum_accumulator, __m512i &sqsum_accumulator,
+ int num_ops_in_line)
+ {
+ // This function handles full 64 byte chunks of the source data at a time until it gets to the part of
+ // the line that no longer contains a full 64 byte chunk. Other code will handle the last part.
+
+ const int num_chunks = num_ops_in_line >> 6; // quick int divide by 64
+
+ for (int index_64byte_chunk = 0; index_64byte_chunk < num_chunks; index_64byte_chunk++){
+ integral_64_operations_avx512((__m512i *) srcs,
+ (__m512i *) sums, (__m512i *) sums_above,
+ (__m512i *) sqsum, (__m512i *) sqsum_above,
+ 0xFFFFFFFFFFFFFFFF, sum_accumulator, sqsum_accumulator);
+ srcs+=64; sums+=64; sums_above+=64;
+ if (sqsum){ sqsum+= 64; sqsum_above+=64; }
+ }
+ }
+
+
+ static inline
+ void post_aligned_integral(const uchar *srcs,
+ const double *sums, const double *sums_above,
+ const double *sqsum, const double *sqsum_above,
+ __m512i &sum_accumulator, __m512i &sqsum_accumulator,
+ int num_ops_in_line)
+ {
+ // This function handles the last few straggling operations that are not a full chunk of 64 operations
+ // We use the same algorithm, but we calculate a different operation mask using (num_ops % 64).
+
+ const unsigned int num_operations = (unsigned int) num_ops_in_line & 0x3F; // Quick int modulo 64
+
+ if (num_operations > 0) {
+ __mmask64 operation_mask = (1ULL << num_operations) - 1ULL;
+
+ integral_64_operations_avx512((__m512i *) srcs, (__m512i *) sums, (__m512i *) sums_above,
+ (__m512i *) sqsum, (__m512i *) sqsum_above,
+ operation_mask, sum_accumulator, sqsum_accumulator);
+ }
+ }
+
+
+ static inline
+ void integral_64_operations_avx512(const __m512i *srcs,
+ __m512i *sums, const __m512i *sums_above,
+ __m512i *sqsums, const __m512i *sqsums_above,
+ __mmask64 data_mask,
+ __m512i &sum_accumulator, __m512i &sqsum_accumulator)
+ {
+ __m512i src_64byte_chunk = read_64_bytes(srcs, data_mask);
+
+ for(int num_16byte_chunks=0; num_16byte_chunks<4; num_16byte_chunks++) {
+ __m128i src_16bytes = _mm512_extracti64x2_epi64(src_64byte_chunk, 0x0); // Get lower 16 bytes of data
+
+ for (int num_8byte_chunks = 0; num_8byte_chunks < 2; num_8byte_chunks++) {
+
+ __m512i src_longs = convert_lower_8bytes_to_longs(src_16bytes);
+
+ // Calculate integral for the sum on the 8 entries
+ integral_8_operations(src_longs, sums_above, data_mask, sums, sum_accumulator);
+ sums++; sums_above++;
+
+ if (sqsums){ // Calculate integral for the sum on the 8 entries
+ __m512i squared_source = _mm512_mullo_epi64(src_longs, src_longs);
+
+ integral_8_operations(squared_source, sqsums_above, data_mask, sqsums, sqsum_accumulator);
+ sqsums++; sqsums_above++;
+ }
+
+ // Prepare for next iteration of inner loop
+ // shift source to align next 8 bytes to lane 0 and shift the mask
+ src_16bytes = shift_right_8_bytes(src_16bytes);
+ data_mask = data_mask >> 8;
+
+ }
+
+ // Prepare for next iteration of outer loop
+ src_64byte_chunk = shift_right_16_bytes(src_64byte_chunk);
+ }
+ }
+
+
+ static inline
+ void integral_8_operations(const __m512i src_longs, const __m512i *above_values_ptr, __mmask64 data_mask,
+ __m512i *results_ptr, __m512i &accumulator)
+ {
+ _mm512_mask_storeu_pd(
+ results_ptr, // Store the result here
+ data_mask, // Using the data mask to avoid overrunning the line
+ calculate_integral( // Writing the value of the integral derived from:
+ src_longs, // input data
+ _mm512_maskz_loadu_pd(data_mask, above_values_ptr), // and the results from line above
+ accumulator // keeping track of the accumulator
+ )
+ );
+ }
+
+
+ static inline
+ __m512d calculate_integral(__m512i src_longs, const __m512d above_values, __m512i &accumulator)
+ {
+ __m512i carryover_idxs = _mm512_set_epi64(6, 5, 7, 6, 5, 7, 6, 5);
+
+ // Align data to prepare for the adds:
+ // shifts data left by 3 and 6 qwords(lanes) and gets rolling sum in all lanes
+ // Vertical LANES: 76543210
+ // src_longs : HGFEDCBA
+ // shited3lanes : + EDCBA
+ // shifted6lanes : + BA
+ // carry_over_idxs : + 65765765 (index position of result from previous iteration)
+ // = integral
+ __m512i shifted3lanes = _mm512_maskz_expand_epi64(0xF8, src_longs);
+ __m512i shifted6lanes = _mm512_maskz_expand_epi64(0xC0, src_longs);
+ __m512i carry_over = _mm512_permutex2var_epi64(accumulator, carryover_idxs, accumulator);
+
+ // Do the adds in tree form (shift3 + shift 6) + (current_source_values + accumulator)
+ __m512i sum_shift3and6 = _mm512_add_epi64(shifted3lanes, shifted6lanes);
+ __m512i sum_src_carry = _mm512_add_epi64(src_longs, carry_over);
+ accumulator = _mm512_add_epi64(sum_shift3and6, sum_src_carry);
+
+ // Convert to packed double and add to the line above to get the true integral value
+ __m512d accumulator_pd = _mm512_cvtepu64_pd(accumulator);
+ __m512d integral_pd = _mm512_add_pd(accumulator_pd, above_values);
+ return integral_pd;
+ }
+
+
+ static inline
+ __m512i read_64_bytes(const __m512i *srcs, __mmask64 data_mask) {
+ return _mm512_maskz_loadu_epi8(data_mask, srcs);
+ }
+
+
+ static inline
+ __m512i convert_lower_8bytes_to_longs(__m128i src_16bytes) {
+ return _mm512_cvtepu8_epi64(src_16bytes);
+ }
+
+
+ static inline
+ __m128i shift_right_8_bytes(__m128i src_16bytes) {
+ return _mm_maskz_compress_epi64(2, src_16bytes);
+ }
+
+
+ static inline
+ __m512i shift_right_16_bytes(__m512i src_64byte_chunk) {
+ return _mm512_maskz_compress_epi64(0xFC, src_64byte_chunk);
+ }
+
+};
+} // end of anonymous namespace
+
+namespace opt_AVX512_SKX {
+
+// This is the implementation for the external callers interface entry point.
+// It should be the only function called into this file from outside
+// Any new implementations should be directed from here
+void calculate_integral_avx512(const uchar *src, size_t _srcstep,
+ double *sum, size_t _sumstep,
+ double *sqsum, size_t _sqsumstep,
+ int width, int height, int cn)
+{
+ IntegralCalculator_3Channel calculator;
+ calculator.calculate_integral_avx512(src, _srcstep, sum, _sumstep, sqsum, _sqsumstep, width, height, cn);
+}
+
+
+} // end namespace opt_AVX512_SXK
+} // end namespace cv