| 1 | //===-- GPU implementation of the clock function --------------------------===// |
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| 2 | // |
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| 3 | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
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| 4 | // See https://llvm.org/LICENSE.txt for license information. |
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| 5 | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
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| 6 | // |
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| 7 | //===----------------------------------------------------------------------===// |
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| 8 | |
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| 9 | #include "src/time/clock.h" |
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| 10 | |
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| 11 | #include "src/__support/common.h" |
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| 12 | #include "src/__support/macros/config.h" |
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| 13 | #include "src/__support/time/gpu/time_utils.h" |
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| 14 | |
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| 15 | namespace LIBC_NAMESPACE_DECL { |
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| 16 | |
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| 17 | LLVM_LIBC_FUNCTION(clock_t, clock, ()) { |
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| 18 | if (!GPU_CLOCKS_PER_SEC) |
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| 19 | return clock_t(0); |
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| 20 | |
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| 21 | uint64_t ticks = gpu::fixed_frequency_clock(); |
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| 22 | |
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| 23 | // We need to convert between the GPU's fixed frequency and whatever `time.h` |
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| 24 | // declares it to be. This is done so that dividing the result of this |
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| 25 | // function by 'CLOCKS_PER_SEC' yields the elapsed time. |
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| 26 | if (GPU_CLOCKS_PER_SEC > CLOCKS_PER_SEC) |
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| 27 | return clock_t(ticks / (GPU_CLOCKS_PER_SEC / CLOCKS_PER_SEC)); |
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| 28 | return clock_t(ticks * (CLOCKS_PER_SEC / GPU_CLOCKS_PER_SEC)); |
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| 29 | } |
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| 30 | |
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| 31 | } // namespace LIBC_NAMESPACE_DECL |
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| 32 | |
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