From b56cbdd23834a65682c0b46f367f8679e83bc894 Mon Sep 17 00:00:00 2001 From: Abseil Team Date: Fri, 18 Sep 2020 15:55:15 -0700 Subject: Abseil LTS 20200923 What's New: * `absl::StatusOr` has been released. See our [blog post](https://abseil.io/blog/2020-091021-status) for more information. * Abseil Flags reflection interfaces have been released. * Abseil Flags memory usage has been significantly optimized. * Abseil now supports a "hardened" build mode. This build mode enables runtime checks that guard against programming errors that may lead to security vulnerabilities. Notable Fixes: * Sanitizer dynamic annotations like `AnnotateRWLockCreate` that are also defined by the compiler sanitizer implementation are no longer also defined by Abseil. * Sanitizer macros are now prefixed with `ABSL_` to avoid naming collisions. * Sanitizer usage is now automatically detected and no longer requires macros like `ADDRESS_SANITIZER` to be defined on the command line. Breaking Changes: * Abseil no longer contains a `dynamic_annotations` library. Users using a supported build system (Bazel or CMake) are unaffected by this, but users manually specifying link libraries may get an error about a missing linker input. Baseline: 7680a5f8efe32de4753baadbd63e74e59d95bac1 Cherry picks: None --- absl/base/optimization_test.cc | 129 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 129 insertions(+) create mode 100644 absl/base/optimization_test.cc (limited to 'absl/base/optimization_test.cc') diff --git a/absl/base/optimization_test.cc b/absl/base/optimization_test.cc new file mode 100644 index 00000000..e83369f3 --- /dev/null +++ b/absl/base/optimization_test.cc @@ -0,0 +1,129 @@ +// Copyright 2020 The Abseil Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// https://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +#include "absl/base/optimization.h" + +#include "gtest/gtest.h" +#include "absl/types/optional.h" + +namespace { + +// Tests for the ABSL_PREDICT_TRUE and ABSL_PREDICT_FALSE macros. +// The tests only verify that the macros are functionally correct - i.e. code +// behaves as if they weren't used. They don't try to check their impact on +// optimization. + +TEST(PredictTest, PredictTrue) { + EXPECT_TRUE(ABSL_PREDICT_TRUE(true)); + EXPECT_FALSE(ABSL_PREDICT_TRUE(false)); + EXPECT_TRUE(ABSL_PREDICT_TRUE(1 == 1)); + EXPECT_FALSE(ABSL_PREDICT_TRUE(1 == 2)); + + if (ABSL_PREDICT_TRUE(false)) ADD_FAILURE(); + if (!ABSL_PREDICT_TRUE(true)) ADD_FAILURE(); + + EXPECT_TRUE(ABSL_PREDICT_TRUE(true) && true); + EXPECT_TRUE(ABSL_PREDICT_TRUE(true) || false); +} + +TEST(PredictTest, PredictFalse) { + EXPECT_TRUE(ABSL_PREDICT_FALSE(true)); + EXPECT_FALSE(ABSL_PREDICT_FALSE(false)); + EXPECT_TRUE(ABSL_PREDICT_FALSE(1 == 1)); + EXPECT_FALSE(ABSL_PREDICT_FALSE(1 == 2)); + + if (ABSL_PREDICT_FALSE(false)) ADD_FAILURE(); + if (!ABSL_PREDICT_FALSE(true)) ADD_FAILURE(); + + EXPECT_TRUE(ABSL_PREDICT_FALSE(true) && true); + EXPECT_TRUE(ABSL_PREDICT_FALSE(true) || false); +} + +TEST(PredictTest, OneEvaluation) { + // Verify that the expression is only evaluated once. + int x = 0; + if (ABSL_PREDICT_TRUE((++x) == 0)) ADD_FAILURE(); + EXPECT_EQ(x, 1); + if (ABSL_PREDICT_FALSE((++x) == 0)) ADD_FAILURE(); + EXPECT_EQ(x, 2); +} + +TEST(PredictTest, OperatorOrder) { + // Verify that operator order inside and outside the macro behaves well. + // These would fail for a naive '#define ABSL_PREDICT_TRUE(x) x' + EXPECT_TRUE(ABSL_PREDICT_TRUE(1 && 2) == true); + EXPECT_TRUE(ABSL_PREDICT_FALSE(1 && 2) == true); + EXPECT_TRUE(!ABSL_PREDICT_TRUE(1 == 2)); + EXPECT_TRUE(!ABSL_PREDICT_FALSE(1 == 2)); +} + +TEST(PredictTest, Pointer) { + const int x = 3; + const int *good_intptr = &x; + const int *null_intptr = nullptr; + EXPECT_TRUE(ABSL_PREDICT_TRUE(good_intptr)); + EXPECT_FALSE(ABSL_PREDICT_TRUE(null_intptr)); + EXPECT_TRUE(ABSL_PREDICT_FALSE(good_intptr)); + EXPECT_FALSE(ABSL_PREDICT_FALSE(null_intptr)); +} + +TEST(PredictTest, Optional) { + // Note: An optional's truth value is the value's existence, not its truth. + absl::optional has_value(false); + absl::optional no_value; + EXPECT_TRUE(ABSL_PREDICT_TRUE(has_value)); + EXPECT_FALSE(ABSL_PREDICT_TRUE(no_value)); + EXPECT_TRUE(ABSL_PREDICT_FALSE(has_value)); + EXPECT_FALSE(ABSL_PREDICT_FALSE(no_value)); +} + +class ImplictlyConvertibleToBool { + public: + explicit ImplictlyConvertibleToBool(bool value) : value_(value) {} + operator bool() const { // NOLINT(google-explicit-constructor) + return value_; + } + + private: + bool value_; +}; + +TEST(PredictTest, ImplicitBoolConversion) { + const ImplictlyConvertibleToBool is_true(true); + const ImplictlyConvertibleToBool is_false(false); + if (!ABSL_PREDICT_TRUE(is_true)) ADD_FAILURE(); + if (ABSL_PREDICT_TRUE(is_false)) ADD_FAILURE(); + if (!ABSL_PREDICT_FALSE(is_true)) ADD_FAILURE(); + if (ABSL_PREDICT_FALSE(is_false)) ADD_FAILURE(); +} + +class ExplictlyConvertibleToBool { + public: + explicit ExplictlyConvertibleToBool(bool value) : value_(value) {} + explicit operator bool() const { return value_; } + + private: + bool value_; +}; + +TEST(PredictTest, ExplicitBoolConversion) { + const ExplictlyConvertibleToBool is_true(true); + const ExplictlyConvertibleToBool is_false(false); + if (!ABSL_PREDICT_TRUE(is_true)) ADD_FAILURE(); + if (ABSL_PREDICT_TRUE(is_false)) ADD_FAILURE(); + if (!ABSL_PREDICT_FALSE(is_true)) ADD_FAILURE(); + if (ABSL_PREDICT_FALSE(is_false)) ADD_FAILURE(); +} + +} // namespace -- cgit v1.2.3