mirror of
https://github.com/NVIDIA/cuda-samples.git
synced 2024-11-24 21:49:15 +08:00
530 lines
19 KiB
Plaintext
530 lines
19 KiB
Plaintext
/* Copyright (c) 2022, NVIDIA CORPORATION. All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* * Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* * Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
* * Neither the name of NVIDIA CORPORATION nor the names of its
|
|
* contributors may be used to endorse or promote products derived
|
|
* from this software without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS ``AS IS'' AND ANY
|
|
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
|
|
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
|
|
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
|
|
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
|
|
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
|
|
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
|
|
* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
|
|
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
|
|
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
|
*/
|
|
|
|
/*
|
|
* Based on "Designing efficient sorting algorithms for manycore GPUs"
|
|
* by Nadathur Satish, Mark Harris, and Michael Garland
|
|
* http://mgarland.org/files/papers/gpusort-ipdps09.pdf
|
|
*
|
|
* Victor Podlozhnyuk 09/24/2009
|
|
*/
|
|
|
|
#include <assert.h>
|
|
#include <cooperative_groups.h>
|
|
|
|
namespace cg = cooperative_groups;
|
|
|
|
#include <helper_cuda.h>
|
|
#include "mergeSort_common.h"
|
|
|
|
////////////////////////////////////////////////////////////////////////////////
|
|
// Helper functions
|
|
////////////////////////////////////////////////////////////////////////////////
|
|
static inline __host__ __device__ uint iDivUp(uint a, uint b) {
|
|
return ((a % b) == 0) ? (a / b) : (a / b + 1);
|
|
}
|
|
|
|
static inline __host__ __device__ uint getSampleCount(uint dividend) {
|
|
return iDivUp(dividend, SAMPLE_STRIDE);
|
|
}
|
|
|
|
#define W (sizeof(uint) * 8)
|
|
static inline __device__ uint nextPowerOfTwo(uint x) {
|
|
/*
|
|
--x;
|
|
x |= x >> 1;
|
|
x |= x >> 2;
|
|
x |= x >> 4;
|
|
x |= x >> 8;
|
|
x |= x >> 16;
|
|
return ++x;
|
|
*/
|
|
return 1U << (W - __clz(x - 1));
|
|
}
|
|
|
|
template <uint sortDir>
|
|
static inline __device__ uint binarySearchInclusive(uint val, uint *data,
|
|
uint L, uint stride) {
|
|
if (L == 0) {
|
|
return 0;
|
|
}
|
|
|
|
uint pos = 0;
|
|
|
|
for (; stride > 0; stride >>= 1) {
|
|
uint newPos = umin(pos + stride, L);
|
|
|
|
if ((sortDir && (data[newPos - 1] <= val)) ||
|
|
(!sortDir && (data[newPos - 1] >= val))) {
|
|
pos = newPos;
|
|
}
|
|
}
|
|
|
|
return pos;
|
|
}
|
|
|
|
template <uint sortDir>
|
|
static inline __device__ uint binarySearchExclusive(uint val, uint *data,
|
|
uint L, uint stride) {
|
|
if (L == 0) {
|
|
return 0;
|
|
}
|
|
|
|
uint pos = 0;
|
|
|
|
for (; stride > 0; stride >>= 1) {
|
|
uint newPos = umin(pos + stride, L);
|
|
|
|
if ((sortDir && (data[newPos - 1] < val)) ||
|
|
(!sortDir && (data[newPos - 1] > val))) {
|
|
pos = newPos;
|
|
}
|
|
}
|
|
|
|
return pos;
|
|
}
|
|
|
|
////////////////////////////////////////////////////////////////////////////////
|
|
// Bottom-level merge sort (binary search-based)
|
|
////////////////////////////////////////////////////////////////////////////////
|
|
template <uint sortDir>
|
|
__global__ void mergeSortSharedKernel(uint *d_DstKey, uint *d_DstVal,
|
|
uint *d_SrcKey, uint *d_SrcVal,
|
|
uint arrayLength) {
|
|
// Handle to thread block group
|
|
cg::thread_block cta = cg::this_thread_block();
|
|
__shared__ uint s_key[SHARED_SIZE_LIMIT];
|
|
__shared__ uint s_val[SHARED_SIZE_LIMIT];
|
|
|
|
d_SrcKey += blockIdx.x * SHARED_SIZE_LIMIT + threadIdx.x;
|
|
d_SrcVal += blockIdx.x * SHARED_SIZE_LIMIT + threadIdx.x;
|
|
d_DstKey += blockIdx.x * SHARED_SIZE_LIMIT + threadIdx.x;
|
|
d_DstVal += blockIdx.x * SHARED_SIZE_LIMIT + threadIdx.x;
|
|
s_key[threadIdx.x + 0] = d_SrcKey[0];
|
|
s_val[threadIdx.x + 0] = d_SrcVal[0];
|
|
s_key[threadIdx.x + (SHARED_SIZE_LIMIT / 2)] =
|
|
d_SrcKey[(SHARED_SIZE_LIMIT / 2)];
|
|
s_val[threadIdx.x + (SHARED_SIZE_LIMIT / 2)] =
|
|
d_SrcVal[(SHARED_SIZE_LIMIT / 2)];
|
|
|
|
for (uint stride = 1; stride < arrayLength; stride <<= 1) {
|
|
uint lPos = threadIdx.x & (stride - 1);
|
|
uint *baseKey = s_key + 2 * (threadIdx.x - lPos);
|
|
uint *baseVal = s_val + 2 * (threadIdx.x - lPos);
|
|
|
|
cg::sync(cta);
|
|
uint keyA = baseKey[lPos + 0];
|
|
uint valA = baseVal[lPos + 0];
|
|
uint keyB = baseKey[lPos + stride];
|
|
uint valB = baseVal[lPos + stride];
|
|
uint posA =
|
|
binarySearchExclusive<sortDir>(keyA, baseKey + stride, stride, stride) +
|
|
lPos;
|
|
uint posB =
|
|
binarySearchInclusive<sortDir>(keyB, baseKey + 0, stride, stride) +
|
|
lPos;
|
|
|
|
cg::sync(cta);
|
|
baseKey[posA] = keyA;
|
|
baseVal[posA] = valA;
|
|
baseKey[posB] = keyB;
|
|
baseVal[posB] = valB;
|
|
}
|
|
|
|
cg::sync(cta);
|
|
d_DstKey[0] = s_key[threadIdx.x + 0];
|
|
d_DstVal[0] = s_val[threadIdx.x + 0];
|
|
d_DstKey[(SHARED_SIZE_LIMIT / 2)] =
|
|
s_key[threadIdx.x + (SHARED_SIZE_LIMIT / 2)];
|
|
d_DstVal[(SHARED_SIZE_LIMIT / 2)] =
|
|
s_val[threadIdx.x + (SHARED_SIZE_LIMIT / 2)];
|
|
}
|
|
|
|
static void mergeSortShared(uint *d_DstKey, uint *d_DstVal, uint *d_SrcKey,
|
|
uint *d_SrcVal, uint batchSize, uint arrayLength,
|
|
uint sortDir) {
|
|
if (arrayLength < 2) {
|
|
return;
|
|
}
|
|
|
|
assert(SHARED_SIZE_LIMIT % arrayLength == 0);
|
|
assert(((batchSize * arrayLength) % SHARED_SIZE_LIMIT) == 0);
|
|
uint blockCount = batchSize * arrayLength / SHARED_SIZE_LIMIT;
|
|
uint threadCount = SHARED_SIZE_LIMIT / 2;
|
|
|
|
if (sortDir) {
|
|
mergeSortSharedKernel<1U><<<blockCount, threadCount>>>(
|
|
d_DstKey, d_DstVal, d_SrcKey, d_SrcVal, arrayLength);
|
|
getLastCudaError("mergeSortShared<1><<<>>> failed\n");
|
|
} else {
|
|
mergeSortSharedKernel<0U><<<blockCount, threadCount>>>(
|
|
d_DstKey, d_DstVal, d_SrcKey, d_SrcVal, arrayLength);
|
|
getLastCudaError("mergeSortShared<0><<<>>> failed\n");
|
|
}
|
|
}
|
|
|
|
////////////////////////////////////////////////////////////////////////////////
|
|
// Merge step 1: generate sample ranks
|
|
////////////////////////////////////////////////////////////////////////////////
|
|
template <uint sortDir>
|
|
__global__ void generateSampleRanksKernel(uint *d_RanksA, uint *d_RanksB,
|
|
uint *d_SrcKey, uint stride, uint N,
|
|
uint threadCount) {
|
|
uint pos = blockIdx.x * blockDim.x + threadIdx.x;
|
|
|
|
if (pos >= threadCount) {
|
|
return;
|
|
}
|
|
|
|
const uint i = pos & ((stride / SAMPLE_STRIDE) - 1);
|
|
const uint segmentBase = (pos - i) * (2 * SAMPLE_STRIDE);
|
|
d_SrcKey += segmentBase;
|
|
d_RanksA += segmentBase / SAMPLE_STRIDE;
|
|
d_RanksB += segmentBase / SAMPLE_STRIDE;
|
|
|
|
const uint segmentElementsA = stride;
|
|
const uint segmentElementsB = umin(stride, N - segmentBase - stride);
|
|
const uint segmentSamplesA = getSampleCount(segmentElementsA);
|
|
const uint segmentSamplesB = getSampleCount(segmentElementsB);
|
|
|
|
if (i < segmentSamplesA) {
|
|
d_RanksA[i] = i * SAMPLE_STRIDE;
|
|
d_RanksB[i] = binarySearchExclusive<sortDir>(
|
|
d_SrcKey[i * SAMPLE_STRIDE], d_SrcKey + stride, segmentElementsB,
|
|
nextPowerOfTwo(segmentElementsB));
|
|
}
|
|
|
|
if (i < segmentSamplesB) {
|
|
d_RanksB[(stride / SAMPLE_STRIDE) + i] = i * SAMPLE_STRIDE;
|
|
d_RanksA[(stride / SAMPLE_STRIDE) + i] = binarySearchInclusive<sortDir>(
|
|
d_SrcKey[stride + i * SAMPLE_STRIDE], d_SrcKey + 0, segmentElementsA,
|
|
nextPowerOfTwo(segmentElementsA));
|
|
}
|
|
}
|
|
|
|
static void generateSampleRanks(uint *d_RanksA, uint *d_RanksB, uint *d_SrcKey,
|
|
uint stride, uint N, uint sortDir) {
|
|
uint lastSegmentElements = N % (2 * stride);
|
|
uint threadCount =
|
|
(lastSegmentElements > stride)
|
|
? (N + 2 * stride - lastSegmentElements) / (2 * SAMPLE_STRIDE)
|
|
: (N - lastSegmentElements) / (2 * SAMPLE_STRIDE);
|
|
|
|
if (sortDir) {
|
|
generateSampleRanksKernel<1U><<<iDivUp(threadCount, 256), 256>>>(
|
|
d_RanksA, d_RanksB, d_SrcKey, stride, N, threadCount);
|
|
getLastCudaError("generateSampleRanksKernel<1U><<<>>> failed\n");
|
|
} else {
|
|
generateSampleRanksKernel<0U><<<iDivUp(threadCount, 256), 256>>>(
|
|
d_RanksA, d_RanksB, d_SrcKey, stride, N, threadCount);
|
|
getLastCudaError("generateSampleRanksKernel<0U><<<>>> failed\n");
|
|
}
|
|
}
|
|
|
|
////////////////////////////////////////////////////////////////////////////////
|
|
// Merge step 2: generate sample ranks and indices
|
|
////////////////////////////////////////////////////////////////////////////////
|
|
__global__ void mergeRanksAndIndicesKernel(uint *d_Limits, uint *d_Ranks,
|
|
uint stride, uint N,
|
|
uint threadCount) {
|
|
uint pos = blockIdx.x * blockDim.x + threadIdx.x;
|
|
|
|
if (pos >= threadCount) {
|
|
return;
|
|
}
|
|
|
|
const uint i = pos & ((stride / SAMPLE_STRIDE) - 1);
|
|
const uint segmentBase = (pos - i) * (2 * SAMPLE_STRIDE);
|
|
d_Ranks += (pos - i) * 2;
|
|
d_Limits += (pos - i) * 2;
|
|
|
|
const uint segmentElementsA = stride;
|
|
const uint segmentElementsB = umin(stride, N - segmentBase - stride);
|
|
const uint segmentSamplesA = getSampleCount(segmentElementsA);
|
|
const uint segmentSamplesB = getSampleCount(segmentElementsB);
|
|
|
|
if (i < segmentSamplesA) {
|
|
uint dstPos = binarySearchExclusive<1U>(
|
|
d_Ranks[i], d_Ranks + segmentSamplesA, segmentSamplesB,
|
|
nextPowerOfTwo(segmentSamplesB)) +
|
|
i;
|
|
d_Limits[dstPos] = d_Ranks[i];
|
|
}
|
|
|
|
if (i < segmentSamplesB) {
|
|
uint dstPos = binarySearchInclusive<1U>(d_Ranks[segmentSamplesA + i],
|
|
d_Ranks, segmentSamplesA,
|
|
nextPowerOfTwo(segmentSamplesA)) +
|
|
i;
|
|
d_Limits[dstPos] = d_Ranks[segmentSamplesA + i];
|
|
}
|
|
}
|
|
|
|
static void mergeRanksAndIndices(uint *d_LimitsA, uint *d_LimitsB,
|
|
uint *d_RanksA, uint *d_RanksB, uint stride,
|
|
uint N) {
|
|
uint lastSegmentElements = N % (2 * stride);
|
|
uint threadCount =
|
|
(lastSegmentElements > stride)
|
|
? (N + 2 * stride - lastSegmentElements) / (2 * SAMPLE_STRIDE)
|
|
: (N - lastSegmentElements) / (2 * SAMPLE_STRIDE);
|
|
|
|
mergeRanksAndIndicesKernel<<<iDivUp(threadCount, 256), 256>>>(
|
|
d_LimitsA, d_RanksA, stride, N, threadCount);
|
|
getLastCudaError("mergeRanksAndIndicesKernel(A)<<<>>> failed\n");
|
|
|
|
mergeRanksAndIndicesKernel<<<iDivUp(threadCount, 256), 256>>>(
|
|
d_LimitsB, d_RanksB, stride, N, threadCount);
|
|
getLastCudaError("mergeRanksAndIndicesKernel(B)<<<>>> failed\n");
|
|
}
|
|
|
|
////////////////////////////////////////////////////////////////////////////////
|
|
// Merge step 3: merge elementary intervals
|
|
////////////////////////////////////////////////////////////////////////////////
|
|
template <uint sortDir>
|
|
inline __device__ void merge(uint *dstKey, uint *dstVal, uint *srcAKey,
|
|
uint *srcAVal, uint *srcBKey, uint *srcBVal,
|
|
uint lenA, uint nPowTwoLenA, uint lenB,
|
|
uint nPowTwoLenB, cg::thread_block cta) {
|
|
uint keyA, valA, keyB, valB, dstPosA, dstPosB;
|
|
|
|
if (threadIdx.x < lenA) {
|
|
keyA = srcAKey[threadIdx.x];
|
|
valA = srcAVal[threadIdx.x];
|
|
dstPosA = binarySearchExclusive<sortDir>(keyA, srcBKey, lenB, nPowTwoLenB) +
|
|
threadIdx.x;
|
|
}
|
|
|
|
if (threadIdx.x < lenB) {
|
|
keyB = srcBKey[threadIdx.x];
|
|
valB = srcBVal[threadIdx.x];
|
|
dstPosB = binarySearchInclusive<sortDir>(keyB, srcAKey, lenA, nPowTwoLenA) +
|
|
threadIdx.x;
|
|
}
|
|
|
|
cg::sync(cta);
|
|
|
|
if (threadIdx.x < lenA) {
|
|
dstKey[dstPosA] = keyA;
|
|
dstVal[dstPosA] = valA;
|
|
}
|
|
|
|
if (threadIdx.x < lenB) {
|
|
dstKey[dstPosB] = keyB;
|
|
dstVal[dstPosB] = valB;
|
|
}
|
|
}
|
|
|
|
template <uint sortDir>
|
|
__global__ void mergeElementaryIntervalsKernel(uint *d_DstKey, uint *d_DstVal,
|
|
uint *d_SrcKey, uint *d_SrcVal,
|
|
uint *d_LimitsA, uint *d_LimitsB,
|
|
uint stride, uint N) {
|
|
// Handle to thread block group
|
|
cg::thread_block cta = cg::this_thread_block();
|
|
__shared__ uint s_key[2 * SAMPLE_STRIDE];
|
|
__shared__ uint s_val[2 * SAMPLE_STRIDE];
|
|
|
|
const uint intervalI = blockIdx.x & ((2 * stride) / SAMPLE_STRIDE - 1);
|
|
const uint segmentBase = (blockIdx.x - intervalI) * SAMPLE_STRIDE;
|
|
d_SrcKey += segmentBase;
|
|
d_SrcVal += segmentBase;
|
|
d_DstKey += segmentBase;
|
|
d_DstVal += segmentBase;
|
|
|
|
// Set up threadblock-wide parameters
|
|
__shared__ uint startSrcA, startSrcB, lenSrcA, lenSrcB, startDstA, startDstB;
|
|
|
|
if (threadIdx.x == 0) {
|
|
uint segmentElementsA = stride;
|
|
uint segmentElementsB = umin(stride, N - segmentBase - stride);
|
|
uint segmentSamplesA = getSampleCount(segmentElementsA);
|
|
uint segmentSamplesB = getSampleCount(segmentElementsB);
|
|
uint segmentSamples = segmentSamplesA + segmentSamplesB;
|
|
|
|
startSrcA = d_LimitsA[blockIdx.x];
|
|
startSrcB = d_LimitsB[blockIdx.x];
|
|
uint endSrcA = (intervalI + 1 < segmentSamples) ? d_LimitsA[blockIdx.x + 1]
|
|
: segmentElementsA;
|
|
uint endSrcB = (intervalI + 1 < segmentSamples) ? d_LimitsB[blockIdx.x + 1]
|
|
: segmentElementsB;
|
|
lenSrcA = endSrcA - startSrcA;
|
|
lenSrcB = endSrcB - startSrcB;
|
|
startDstA = startSrcA + startSrcB;
|
|
startDstB = startDstA + lenSrcA;
|
|
}
|
|
|
|
// Load main input data
|
|
cg::sync(cta);
|
|
|
|
if (threadIdx.x < lenSrcA) {
|
|
s_key[threadIdx.x + 0] = d_SrcKey[0 + startSrcA + threadIdx.x];
|
|
s_val[threadIdx.x + 0] = d_SrcVal[0 + startSrcA + threadIdx.x];
|
|
}
|
|
|
|
if (threadIdx.x < lenSrcB) {
|
|
s_key[threadIdx.x + SAMPLE_STRIDE] =
|
|
d_SrcKey[stride + startSrcB + threadIdx.x];
|
|
s_val[threadIdx.x + SAMPLE_STRIDE] =
|
|
d_SrcVal[stride + startSrcB + threadIdx.x];
|
|
}
|
|
|
|
// Merge data in shared memory
|
|
cg::sync(cta);
|
|
merge<sortDir>(s_key, s_val, s_key + 0, s_val + 0, s_key + SAMPLE_STRIDE,
|
|
s_val + SAMPLE_STRIDE, lenSrcA, SAMPLE_STRIDE, lenSrcB,
|
|
SAMPLE_STRIDE, cta);
|
|
|
|
// Store merged data
|
|
cg::sync(cta);
|
|
|
|
if (threadIdx.x < lenSrcA) {
|
|
d_DstKey[startDstA + threadIdx.x] = s_key[threadIdx.x];
|
|
d_DstVal[startDstA + threadIdx.x] = s_val[threadIdx.x];
|
|
}
|
|
|
|
if (threadIdx.x < lenSrcB) {
|
|
d_DstKey[startDstB + threadIdx.x] = s_key[lenSrcA + threadIdx.x];
|
|
d_DstVal[startDstB + threadIdx.x] = s_val[lenSrcA + threadIdx.x];
|
|
}
|
|
}
|
|
|
|
static void mergeElementaryIntervals(uint *d_DstKey, uint *d_DstVal,
|
|
uint *d_SrcKey, uint *d_SrcVal,
|
|
uint *d_LimitsA, uint *d_LimitsB,
|
|
uint stride, uint N, uint sortDir) {
|
|
uint lastSegmentElements = N % (2 * stride);
|
|
uint mergePairs = (lastSegmentElements > stride)
|
|
? getSampleCount(N)
|
|
: (N - lastSegmentElements) / SAMPLE_STRIDE;
|
|
|
|
if (sortDir) {
|
|
mergeElementaryIntervalsKernel<1U><<<mergePairs, SAMPLE_STRIDE>>>(
|
|
d_DstKey, d_DstVal, d_SrcKey, d_SrcVal, d_LimitsA, d_LimitsB, stride,
|
|
N);
|
|
getLastCudaError("mergeElementaryIntervalsKernel<1> failed\n");
|
|
} else {
|
|
mergeElementaryIntervalsKernel<0U><<<mergePairs, SAMPLE_STRIDE>>>(
|
|
d_DstKey, d_DstVal, d_SrcKey, d_SrcVal, d_LimitsA, d_LimitsB, stride,
|
|
N);
|
|
getLastCudaError("mergeElementaryIntervalsKernel<0> failed\n");
|
|
}
|
|
}
|
|
|
|
extern "C" void bitonicSortShared(uint *d_DstKey, uint *d_DstVal,
|
|
uint *d_SrcKey, uint *d_SrcVal,
|
|
uint batchSize, uint arrayLength,
|
|
uint sortDir);
|
|
|
|
extern "C" void bitonicMergeElementaryIntervals(uint *d_DstKey, uint *d_DstVal,
|
|
uint *d_SrcKey, uint *d_SrcVal,
|
|
uint *d_LimitsA,
|
|
uint *d_LimitsB, uint stride,
|
|
uint N, uint sortDir);
|
|
|
|
static uint *d_RanksA, *d_RanksB, *d_LimitsA, *d_LimitsB;
|
|
static const uint MAX_SAMPLE_COUNT = 32768;
|
|
|
|
extern "C" void initMergeSort(void) {
|
|
checkCudaErrors(
|
|
cudaMalloc((void **)&d_RanksA, MAX_SAMPLE_COUNT * sizeof(uint)));
|
|
checkCudaErrors(
|
|
cudaMalloc((void **)&d_RanksB, MAX_SAMPLE_COUNT * sizeof(uint)));
|
|
checkCudaErrors(
|
|
cudaMalloc((void **)&d_LimitsA, MAX_SAMPLE_COUNT * sizeof(uint)));
|
|
checkCudaErrors(
|
|
cudaMalloc((void **)&d_LimitsB, MAX_SAMPLE_COUNT * sizeof(uint)));
|
|
}
|
|
|
|
extern "C" void closeMergeSort(void) {
|
|
checkCudaErrors(cudaFree(d_RanksA));
|
|
checkCudaErrors(cudaFree(d_RanksB));
|
|
checkCudaErrors(cudaFree(d_LimitsB));
|
|
checkCudaErrors(cudaFree(d_LimitsA));
|
|
}
|
|
|
|
extern "C" void mergeSort(uint *d_DstKey, uint *d_DstVal, uint *d_BufKey,
|
|
uint *d_BufVal, uint *d_SrcKey, uint *d_SrcVal,
|
|
uint N, uint sortDir) {
|
|
uint stageCount = 0;
|
|
|
|
for (uint stride = SHARED_SIZE_LIMIT; stride < N; stride <<= 1, stageCount++)
|
|
;
|
|
|
|
uint *ikey, *ival, *okey, *oval;
|
|
|
|
if (stageCount & 1) {
|
|
ikey = d_BufKey;
|
|
ival = d_BufVal;
|
|
okey = d_DstKey;
|
|
oval = d_DstVal;
|
|
} else {
|
|
ikey = d_DstKey;
|
|
ival = d_DstVal;
|
|
okey = d_BufKey;
|
|
oval = d_BufVal;
|
|
}
|
|
|
|
assert(N <= (SAMPLE_STRIDE * MAX_SAMPLE_COUNT));
|
|
assert(N % SHARED_SIZE_LIMIT == 0);
|
|
mergeSortShared(ikey, ival, d_SrcKey, d_SrcVal, N / SHARED_SIZE_LIMIT,
|
|
SHARED_SIZE_LIMIT, sortDir);
|
|
|
|
for (uint stride = SHARED_SIZE_LIMIT; stride < N; stride <<= 1) {
|
|
uint lastSegmentElements = N % (2 * stride);
|
|
|
|
// Find sample ranks and prepare for limiters merge
|
|
generateSampleRanks(d_RanksA, d_RanksB, ikey, stride, N, sortDir);
|
|
|
|
// Merge ranks and indices
|
|
mergeRanksAndIndices(d_LimitsA, d_LimitsB, d_RanksA, d_RanksB, stride, N);
|
|
|
|
// Merge elementary intervals
|
|
mergeElementaryIntervals(okey, oval, ikey, ival, d_LimitsA, d_LimitsB,
|
|
stride, N, sortDir);
|
|
|
|
if (lastSegmentElements <= stride) {
|
|
// Last merge segment consists of a single array which just needs to be
|
|
// passed through
|
|
checkCudaErrors(cudaMemcpy(
|
|
okey + (N - lastSegmentElements), ikey + (N - lastSegmentElements),
|
|
lastSegmentElements * sizeof(uint), cudaMemcpyDeviceToDevice));
|
|
checkCudaErrors(cudaMemcpy(
|
|
oval + (N - lastSegmentElements), ival + (N - lastSegmentElements),
|
|
lastSegmentElements * sizeof(uint), cudaMemcpyDeviceToDevice));
|
|
}
|
|
|
|
uint *t;
|
|
t = ikey;
|
|
ikey = okey;
|
|
okey = t;
|
|
t = ival;
|
|
ival = oval;
|
|
oval = t;
|
|
}
|
|
}
|