45 lines
1.3 KiB
Plaintext
45 lines
1.3 KiB
Plaintext
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#include <thrust/device_free.h>
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#include <thrust/device_malloc.h>
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#include <thrust/device_ptr.h>
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#include <thrust/reduce.h>
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#include <thrust/sequence.h>
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#include <cassert>
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#include <iostream>
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int main()
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{
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// allocate memory buffer to store 10 integers on the device
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thrust::device_ptr<int> d_ptr = thrust::device_malloc<int>(10);
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// device_ptr supports pointer arithmetic
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thrust::device_ptr<int> first = d_ptr;
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thrust::device_ptr<int> last = d_ptr + 10;
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std::cout << "device array contains " << cuda::std::distance(first, last) << " values\n";
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// algorithms work as expected
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thrust::sequence(first, last);
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std::cout << "sum of values is " << thrust::reduce(first, last) << "\n";
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// device memory can be read and written transparently
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d_ptr[0] = 10;
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d_ptr[1] = 11;
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d_ptr[2] = d_ptr[0] + d_ptr[1];
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// device_ptr can be converted to a "raw" pointer for use in other APIs and kernels, etc.
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int* raw_ptr = thrust::raw_pointer_cast(d_ptr);
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// note: raw_ptr cannot necessarily be accessed by the host!
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// conversely, raw pointers can be wrapped
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[[maybe_unused]] thrust::device_ptr<int> wrapped_ptr = thrust::device_pointer_cast(raw_ptr);
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// back to where we started
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assert(wrapped_ptr == d_ptr);
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// deallocate device memory
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thrust::device_free(d_ptr);
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return 0;
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}
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