refactor: Remove quick math helpers (#3701)

This has proven not to be useful as `std` math functions are not really a bottleneck in our current code. I propose to remove them here. If they become useful in the future we can just bring them back from here.
acts-project · Oct 9, 2024 · e6400b6 · e6400b6
1 parent 69e0b6b
commit e6400b6
Show file tree

Hide file tree

Showing 7 changed files with 2 additions and 264 deletions.
diff --git a/Core/include/Acts/Propagator/EigenStepper.ipp b/Core/include/Acts/Propagator/EigenStepper.ipp
@@ -10,7 +10,6 @@
 #include "Acts/Propagator/ConstrainedStep.hpp"
 #include "Acts/Propagator/EigenStepperError.hpp"
 #include "Acts/Propagator/detail/CovarianceEngine.hpp"
-#include "Acts/Utilities/QuickMath.hpp"
 
 #include <limits>
 
@@ -177,17 +176,11 @@ Acts::Result<double> Acts::EigenStepper<E>::step(
     // This is given by the order of the Runge-Kutta method
     constexpr double exponent = 0.25;
 
-    // Whether to use fast power function if available
-    constexpr bool tryUseFastPow{false};
-
     double x = state.options.stepping.stepTolerance / errorEstimate_;
 
-    if constexpr (exponent == 0.25 && !tryUseFastPow) {
+    if constexpr (exponent == 0.25) {
       // This is 3x faster than std::pow
       x = std::sqrt(std::sqrt(x));
-    } else if constexpr (std::numeric_limits<double>::is_iec559 &&
-                         tryUseFastPow) {
-      x = fastPow(x, exponent);
     } else {
       x = std::pow(x, exponent);
     }

diff --git a/Core/include/Acts/Utilities/QuickMath.hpp b/Core/include/Acts/Utilities/QuickMath.hpp
diff --git a/Core/src/Propagator/SympyStepper.cpp b/Core/src/Propagator/SympyStepper.cpp
@@ -10,7 +10,6 @@
 
 #include "Acts/Propagator/detail/SympyCovarianceEngine.hpp"
 #include "Acts/Propagator/detail/SympyJacobianEngine.hpp"
-#include "Acts/Utilities/QuickMath.hpp"
 
 #include <cmath>
 #include <cstdint>
@@ -127,17 +126,11 @@ Result<double> SympyStepper::stepImpl(
     // This is given by the order of the Runge-Kutta method
     constexpr double exponent = 0.25;
 
-    // Whether to use fast power function if available
-    constexpr bool tryUseFastPow{false};
-
     double x = stepTolerance / errorEstimate_;
 
-    if constexpr (exponent == 0.25 && !tryUseFastPow) {
+    if constexpr (exponent == 0.25) {
       // This is 3x faster than std::pow
       x = std::sqrt(std::sqrt(x));
-    } else if constexpr (std::numeric_limits<double>::is_iec559 &&
-                         tryUseFastPow) {
-      x = fastPow(x, exponent);
     } else {
       x = std::pow(x, exponent);
     }

diff --git a/Tests/Benchmarks/CMakeLists.txt b/Tests/Benchmarks/CMakeLists.txt
@@ -29,7 +29,6 @@ add_benchmark(SurfaceIntersection SurfaceIntersectionBenchmark.cpp)
 add_benchmark(RayFrustum RayFrustumBenchmark.cpp)
 add_benchmark(AnnulusBounds AnnulusBoundsBenchmark.cpp)
 add_benchmark(StraightLineStepper StraightLineStepperBenchmark.cpp)
-add_benchmark(QuickMath QuickMathBenchmark.cpp)
 add_benchmark(SympyStepper SympyStepperBenchmark.cpp)
 add_benchmark(Stepper StepperBenchmark.cpp)
 add_benchmark(SourceLink SourceLinkBenchmark.cpp)
diff --git a/Tests/Benchmarks/QuickMathBenchmark.cpp b/Tests/Benchmarks/QuickMathBenchmark.cpp
diff --git a/Tests/UnitTests/Core/Utilities/CMakeLists.txt b/Tests/UnitTests/Core/Utilities/CMakeLists.txt
@@ -54,7 +54,6 @@ target_compile_definitions(
 add_unittest(ParticleData ParticleDataTests.cpp)
 add_unittest(Zip ZipTests.cpp)
 add_unittest(TransformRange TransformRangeTests.cpp)
-add_unittest(QuickMath QuickMathTests.cpp)
 
 add_unittest(TrackHelpers TrackHelpersTests.cpp)
 add_unittest(GraphViz GraphVizTests.cpp)
diff --git a/Tests/UnitTests/Core/Utilities/QuickMathTests.cpp b/Tests/UnitTests/Core/Utilities/QuickMathTests.cpp