Adding upstream version 115.7.0esr.upstream/115.7.0esr

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 297 insertions, 0 deletions

diff --git a/xpcom/rust/gtest/bench-collections/Bench.cpp b/xpcom/rust/gtest/bench-collections/Bench.cpp
new file mode 100644
index 0000000000..41152470c7
--- /dev/null
+++ b/xpcom/rust/gtest/bench-collections/Bench.cpp
@@ -0,0 +1,297 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// Overview
+// --------
+// This file measures the speed of various implementations of C++ and Rust
+// collections (hash tables, etc.) used within the codebase. There are a small
+// number of benchmarks for each collection type; each benchmark tests certain
+// operations (insertion, lookup, iteration, etc.) More benchmarks could easily
+// be envisioned, but this small number is enough to characterize the major
+// differences between implementations, while keeping the file size and
+// complexity low.
+//
+// Details
+// -------
+// The file uses `MOZ_GTEST_BENCH_F` so that results are integrated into
+// PerfHerder. It is also designed so that individual test benchmarks can be
+// run under a profiler.
+//
+// The C++ code uses `MOZ_RELEASE_ASSERT` extensively to check values and
+// ensure operations aren't optimized away by the compiler. The Rust code uses
+// `assert!()`. These should be roughly equivalent, but aren't guaranteed to be
+// the same. As a result, the intra-C++ comparisons should be reliable, and the
+// intra-Rust comparisons should be reliable, but the C++ vs. Rust comparisons
+// may be less reliable.
+//
+// Note that the Rust implementations run very slowly without --enable-release.
+//
+// Profiling
+// ---------
+// If you want to measure a particular implementation under a profiler such as
+// Callgrind, do something like this:
+//
+//   MOZ_RUN_GTEST=1 GTEST_FILTER='*BenchCollections*$IMPL*'
+//       valgrind --tool=callgrind --callgrind-out-file=clgout
+//       $OBJDIR/dist/bin/firefox -unittest
+//   callgrind_annotate --auto=yes clgout > clgann
+//
+// where $IMPL is part of an implementation name in a test (e.g. "PLDHash",
+// "MozHash") and $OBJDIR is an objdir containing a --enable-release build.
+//
+// Note that multiple processes are spawned, so `clgout` gets overwritten
+// multiple times, but the last process to write its profiling data to file is
+// the one of interest. (Alternatively, use --callgrind-out-file=clgout.%p to
+// get separate output files for each process, with a PID suffix.)
+
+#include "gtest/gtest.h"
+#include "gtest/MozGTestBench.h"  // For MOZ_GTEST_BENCH
+#include "mozilla/AllocPolicy.h"
+#include "mozilla/ArrayUtils.h"
+#include "mozilla/HashFunctions.h"
+#include "mozilla/HashTable.h"
+#include "mozilla/StaticMutex.h"
+#include "mozilla/TimeStamp.h"
+#include "PLDHashTable.h"
+#include <unordered_set>
+
+using namespace mozilla;
+
+// This function gives a pseudo-random sequence with the following properties:
+// - Deterministic and platform-independent.
+// - No duplicates in the first VALS_LEN results, which is useful for ensuring
+//   the tables get to a particular size, and also for guaranteeing lookups
+//   that fail.
+static uintptr_t MyRand() {
+  static uintptr_t s = 0;
+  s = s * 1103515245 + 12345;
+  return s;
+}
+
+// Keep this in sync with Params in bench.rs.
+struct Params {
+  const char* mConfigName;
+  size_t mNumInserts;            // Insert this many unique keys
+  size_t mNumSuccessfulLookups;  // Does mNumInserts lookups each time
+  size_t mNumFailingLookups;     // Does mNumInserts lookups each time
+  size_t mNumIterations;         // Iterates the full table each time
+  bool mRemoveInserts;           // Remove all entries at end?
+};
+
+// We don't use std::unordered_{set,map}, but it's an interesting thing to
+// benchmark against.
+//
+// Keep this in sync with all the other Bench_*() functions.
+static void Bench_Cpp_unordered_set(const Params* aParams, void** aVals,
+                                    size_t aLen) {
+  std::unordered_set<void*> hs;
+
+  for (size_t j = 0; j < aParams->mNumInserts; j++) {
+    hs.insert(aVals[j]);
+  }
+
+  for (size_t i = 0; i < aParams->mNumSuccessfulLookups; i++) {
+    for (size_t j = 0; j < aParams->mNumInserts; j++) {
+      MOZ_RELEASE_ASSERT(hs.find(aVals[j]) != hs.end());
+    }
+  }
+
+  for (size_t i = 0; i < aParams->mNumFailingLookups; i++) {
+    for (size_t j = aParams->mNumInserts; j < aParams->mNumInserts * 2; j++) {
+      MOZ_RELEASE_ASSERT(hs.find(aVals[j]) == hs.end());
+    }
+  }
+
+  for (size_t i = 0; i < aParams->mNumIterations; i++) {
+    size_t n = 0;
+    for (const auto& elem : hs) {
+      (void)elem;
+      n++;
+    }
+    MOZ_RELEASE_ASSERT(aParams->mNumInserts == n);
+    MOZ_RELEASE_ASSERT(hs.size() == n);
+  }
+
+  if (aParams->mRemoveInserts) {
+    for (size_t j = 0; j < aParams->mNumInserts; j++) {
+      MOZ_RELEASE_ASSERT(hs.erase(aVals[j]) == 1);
+    }
+    MOZ_RELEASE_ASSERT(hs.size() == 0);
+  } else {
+    MOZ_RELEASE_ASSERT(hs.size() == aParams->mNumInserts);
+  }
+}
+
+// Keep this in sync with all the other Bench_*() functions.
+static void Bench_Cpp_PLDHashTable(const Params* aParams, void** aVals,
+                                   size_t aLen) {
+  PLDHashTable hs(PLDHashTable::StubOps(), sizeof(PLDHashEntryStub));
+
+  for (size_t j = 0; j < aParams->mNumInserts; j++) {
+    auto entry = static_cast<PLDHashEntryStub*>(hs.Add(aVals[j]));
+    MOZ_RELEASE_ASSERT(!entry->key);
+    entry->key = aVals[j];
+  }
+
+  for (size_t i = 0; i < aParams->mNumSuccessfulLookups; i++) {
+    for (size_t j = 0; j < aParams->mNumInserts; j++) {
+      MOZ_RELEASE_ASSERT(hs.Search(aVals[j]));
+    }
+  }
+
+  for (size_t i = 0; i < aParams->mNumFailingLookups; i++) {
+    for (size_t j = aParams->mNumInserts; j < aParams->mNumInserts * 2; j++) {
+      MOZ_RELEASE_ASSERT(!hs.Search(aVals[j]));
+    }
+  }
+
+  for (size_t i = 0; i < aParams->mNumIterations; i++) {
+    size_t n = 0;
+    for (auto iter = hs.Iter(); !iter.Done(); iter.Next()) {
+      n++;
+    }
+    MOZ_RELEASE_ASSERT(aParams->mNumInserts == n);
+    MOZ_RELEASE_ASSERT(hs.EntryCount() == n);
+  }
+
+  if (aParams->mRemoveInserts) {
+    for (size_t j = 0; j < aParams->mNumInserts; j++) {
+      hs.Remove(aVals[j]);
+    }
+    MOZ_RELEASE_ASSERT(hs.EntryCount() == 0);
+  } else {
+    MOZ_RELEASE_ASSERT(hs.EntryCount() == aParams->mNumInserts);
+  }
+}
+
+// Keep this in sync with all the other Bench_*() functions.
+static void Bench_Cpp_MozHashSet(const Params* aParams, void** aVals,
+                                 size_t aLen) {
+  mozilla::HashSet<void*, mozilla::DefaultHasher<void*>, MallocAllocPolicy> hs;
+
+  for (size_t j = 0; j < aParams->mNumInserts; j++) {
+    MOZ_RELEASE_ASSERT(hs.put(aVals[j]));
+  }
+
+  for (size_t i = 0; i < aParams->mNumSuccessfulLookups; i++) {
+    for (size_t j = 0; j < aParams->mNumInserts; j++) {
+      MOZ_RELEASE_ASSERT(hs.has(aVals[j]));
+    }
+  }
+
+  for (size_t i = 0; i < aParams->mNumFailingLookups; i++) {
+    for (size_t j = aParams->mNumInserts; j < aParams->mNumInserts * 2; j++) {
+      MOZ_RELEASE_ASSERT(!hs.has(aVals[j]));
+    }
+  }
+
+  for (size_t i = 0; i < aParams->mNumIterations; i++) {
+    size_t n = 0;
+    for (auto iter = hs.iter(); !iter.done(); iter.next()) {
+      n++;
+    }
+    MOZ_RELEASE_ASSERT(aParams->mNumInserts == n);
+    MOZ_RELEASE_ASSERT(hs.count() == n);
+  }
+
+  if (aParams->mRemoveInserts) {
+    for (size_t j = 0; j < aParams->mNumInserts; j++) {
+      hs.remove(aVals[j]);
+    }
+    MOZ_RELEASE_ASSERT(hs.count() == 0);
+  } else {
+    MOZ_RELEASE_ASSERT(hs.count() == aParams->mNumInserts);
+  }
+}
+
+extern "C" {
+void Bench_Rust_HashSet(const Params* params, void** aVals, size_t aLen);
+void Bench_Rust_FnvHashSet(const Params* params, void** aVals, size_t aLen);
+void Bench_Rust_FxHashSet(const Params* params, void** aVals, size_t aLen);
+}
+
+static const size_t VALS_LEN = 131072;
+
+// Each benchmark measures a different aspect of performance.
+// Note that no "Inserts" value can exceed VALS_LEN.
+// Also, if any failing lookups are done, Inserts must be <= VALS_LEN/2.
+const Params gParamsList[] = {
+    // clang-format off
+  //                           Successful Failing              Remove
+  //                 Inserts   lookups    lookups  Iterations  inserts
+  { "succ_lookups",  1024,     5000,      0,       0,          false },
+  { "fail_lookups",  1024,     0,         5000,    0,          false },
+  { "insert_remove", VALS_LEN, 0,         0,       0,          true  },
+  { "iterate",       1024,     0,         0,       5000,       false },
+    // clang-format on
+};
+
+class BenchCollections : public ::testing::Test {
+ protected:
+  void SetUp() override {
+    StaticMutexAutoLock lock(sValsMutex);
+
+    if (!sVals) {
+      sVals = (void**)malloc(VALS_LEN * sizeof(void*));
+      for (size_t i = 0; i < VALS_LEN; i++) {
+        // This leaves the high 32 bits zero on 64-bit platforms, but that
+        // should still be enough randomness to get typical behaviour.
+        sVals[i] = reinterpret_cast<void*>(uintptr_t(MyRand()));
+      }
+    }
+
+    printf("\n");
+    for (size_t i = 0; i < ArrayLength(gParamsList); i++) {
+      const Params* params = &gParamsList[i];
+      printf("%14s", params->mConfigName);
+    }
+    printf("%14s\n", "total");
+  }
+
+ public:
+  void BenchImpl(void (*aBench)(const Params*, void**, size_t)) {
+    StaticMutexAutoLock lock(sValsMutex);
+
+    double total = 0;
+    for (size_t i = 0; i < ArrayLength(gParamsList); i++) {
+      const Params* params = &gParamsList[i];
+      TimeStamp t1 = TimeStamp::Now();
+      aBench(params, sVals, VALS_LEN);
+      TimeStamp t2 = TimeStamp::Now();
+      double t = (t2 - t1).ToMilliseconds();
+      printf("%11.1f ms", t);
+      total += t;
+    }
+    printf("%11.1f ms\n", total);
+  }
+
+ private:
+  // Random values used in the benchmarks.
+  static void** sVals;
+
+  // A mutex that protects all benchmark operations, ensuring that two
+  // benchmarks never run concurrently.
+  static StaticMutex sValsMutex MOZ_UNANNOTATED;
+};
+
+void** BenchCollections::sVals;
+StaticMutex BenchCollections::sValsMutex;
+
+MOZ_GTEST_BENCH_F(BenchCollections, unordered_set,
+                  [this] { BenchImpl(Bench_Cpp_unordered_set); });
+
+MOZ_GTEST_BENCH_F(BenchCollections, PLDHash,
+                  [this] { BenchImpl(Bench_Cpp_PLDHashTable); });
+
+MOZ_GTEST_BENCH_F(BenchCollections, MozHash,
+                  [this] { BenchImpl(Bench_Cpp_MozHashSet); });
+
+MOZ_GTEST_BENCH_F(BenchCollections, RustHash,
+                  [this] { BenchImpl(Bench_Rust_HashSet); });
+
+MOZ_GTEST_BENCH_F(BenchCollections, RustFnvHash,
+                  [this] { BenchImpl(Bench_Rust_FnvHashSet); });
+
+MOZ_GTEST_BENCH_F(BenchCollections, RustFxHash,
+                  [this] { BenchImpl(Bench_Rust_FxHashSet); });