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-rw-r--r--llvm/unittests/FuzzMutate/ReservoirSamplerTest.cpp69
1 files changed, 0 insertions, 69 deletions
diff --git a/llvm/unittests/FuzzMutate/ReservoirSamplerTest.cpp b/llvm/unittests/FuzzMutate/ReservoirSamplerTest.cpp
deleted file mode 100644
index d246ba1428b..00000000000
--- a/llvm/unittests/FuzzMutate/ReservoirSamplerTest.cpp
+++ /dev/null
@@ -1,69 +0,0 @@
-//===- ReservoirSampler.cpp - Tests for the ReservoirSampler --------------===//
-//
-// The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-
-#include "llvm/FuzzMutate/Random.h"
-#include "gtest/gtest.h"
-#include <random>
-
-using namespace llvm;
-
-TEST(ReservoirSamplerTest, OneItem) {
- std::mt19937 Rand;
- auto Sampler = makeSampler(Rand, 7, 1);
- ASSERT_FALSE(Sampler.isEmpty());
- ASSERT_EQ(7, Sampler.getSelection());
-}
-
-TEST(ReservoirSamplerTest, NoWeight) {
- std::mt19937 Rand;
- auto Sampler = makeSampler(Rand, 7, 0);
- ASSERT_TRUE(Sampler.isEmpty());
-}
-
-TEST(ReservoirSamplerTest, Uniform) {
- std::mt19937 Rand;
-
- // Run three chi-squared tests to check that the distribution is reasonably
- // uniform.
- std::vector<int> Items = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9};
-
- int Failures = 0;
- for (int Run = 0; Run < 3; ++Run) {
- std::vector<int> Counts(Items.size(), 0);
-
- // We need $np_s > 5$ at minimum, but we're better off going a couple of
- // orders of magnitude larger.
- int N = Items.size() * 5 * 100;
- for (int I = 0; I < N; ++I) {
- auto Sampler = makeSampler(Rand, Items);
- Counts[Sampler.getSelection()] += 1;
- }
-
- // Knuth. TAOCP Vol. 2, 3.3.1 (8):
- // $V = \frac{1}{n} \sum_{s=1}^{k} \left(\frac{Y_s^2}{p_s}\right) - n$
- double Ps = 1.0 / Items.size();
- double Sum = 0.0;
- for (int Ys : Counts)
- Sum += Ys * Ys / Ps;
- double V = (Sum / N) - N;
-
- assert(Items.size() == 10 && "Our chi-squared values assume 10 items");
- // Since we have 10 items, there are 9 degrees of freedom and the table of
- // chi-squared values is as follows:
- //
- // | p=1% | 5% | 25% | 50% | 75% | 95% | 99% |
- // v=9 | 2.088 | 3.325 | 5.899 | 8.343 | 11.39 | 16.92 | 21.67 |
- //
- // Check that we're in the likely range of results.
- //if (V < 2.088 || V > 21.67)
- if (V < 2.088 || V > 21.67)
- ++Failures;
- }
- EXPECT_LT(Failures, 3) << "Non-uniform distribution?";
-}
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