vendor: OpenCV 5.0.0 snapshot at 40738fb16ceddb5fb3fea747585f7ce6abb0605b

3rdparty/mlas/lib/riscv64/sgemm_pack_b_rvv.cpp

@@ -0,0 +1,115 @@
+/*++
+
+Copyright (c) Microsoft Corporation. All rights reserved.
+
+Licensed under the MIT License.
+
+Module Name:
+
+    sgemm_pack_b_rvv.cpp
+
+Abstract:
+
+    This module implements an RVV packing helper for the single precision
+    matrix/matrix multiply operation (SGEMM) on riscv64.
+
+--*/
+
+#include "mlasi.h"
+
+#if defined(MLAS_USE_RVV)
+
+#include <riscv_vector.h>
+
+namespace {
+
+// Keep MLAS packing in 16-column tiles, but let RVV decide the actual chunk
+// size at runtime via vsetvl so the same code works across different VLENs.
+constexpr size_t kPackedCountN = 16;
+
+MLAS_FORCEINLINE
+void
+MlasStoreZeroPaddedBlock(
+    float* D,
+    const float* B,
+    size_t CountX
+    )
+{
+    size_t remaining = kPackedCountN;
+    size_t offset = 0;
+
+    while (remaining > 0) {
+        const size_t vl = __riscv_vsetvl_e32m4(remaining);
+        __riscv_vse32_v_f32m4(D + offset, __riscv_vfmv_v_f_f32m4(0.0f, vl), vl);
+        offset += vl;
+        remaining -= vl;
+    }
+
+    remaining = CountX;
+    offset = 0;
+
+    while (remaining > 0) {
+        const size_t vl = __riscv_vsetvl_e32m4(remaining);
+        __riscv_vse32_v_f32m4(D + offset, __riscv_vle32_v_f32m4(B + offset, vl), vl);
+        offset += vl;
+        remaining -= vl;
+    }
+}
+
+MLAS_FORCEINLINE
+void
+MlasStoreFullBlock(
+    float* D,
+    const float* B
+    )
+{
+    size_t remaining = kPackedCountN;
+    size_t offset = 0;
+
+    while (remaining > 0) {
+        const size_t vl = __riscv_vsetvl_e32m4(remaining);
+        __riscv_vse32_v_f32m4(D + offset, __riscv_vle32_v_f32m4(B + offset, vl), vl);
+        offset += vl;
+        remaining -= vl;
+    }
+}
+
+}  // namespace
+
+void
+MlasSgemmCopyPackBRvv(
+    float* D,
+    const float* B,
+    size_t ldb,
+    size_t CountX,
+    size_t CountY
+    )
+{
+    while (CountX >= kPackedCountN) {
+        const float* b = B;
+        size_t y = CountY;
+
+        do {
+            MlasStoreFullBlock(D, b);
+            D += kPackedCountN;
+            b += ldb;
+            y--;
+        } while (y > 0);
+
+        B += kPackedCountN;
+        CountX -= kPackedCountN;
+    }
+
+    if (CountX > 0) {
+        size_t y = CountY;
+
+        do {
+            MlasStoreZeroPaddedBlock(D, B, CountX);
+            D += kPackedCountN;
+            B += ldb;
+            y--;
+        } while (y > 0);
+    }
+}
+
+#endif  // defined(MLAS_USE_RVV)