inline_hints : tidy and move more clients

Control/CxxUtils/CxxUtils/inline_hints.h

@@ -24,19 +24,19 @@
  * - The always_inline attibute disables inlining heuristics and inlining is
  * always attempted regardless of optimization level.
  *
- * These can and will affect debug and optimised builds
+ * These can and will affect debug and optimized builds
  *
  * As an example :
  * - We use flatten quite a bit to avoid out of line eigen calls
  * - We use always_inline for helpers containing code that was repeated in
  *   different methods and we factorized it in a separate function.
- *   But we want to keep the semantics of the original
+ *   But we want to keep the semantics of the original code
  * - We use noinline to avoid the compiler being too smart
  *
  * More or less all these assume that given a context one knows something more
  * than the compiler. Inlining (the optimization) can improve or worsen the
- * performance, it can reduce or increase the code size. Check carefully
- * before deciding and confirm.
+ * performance, it can reduce or increase the code size etc
+ * Check carefully before deciding and confirm.
  *
  *
  */
@@ -44,22 +44,15 @@
 #ifndef CXXUTILS_ALWAYS_INLINE_H
 #define CXXUTILS_ALWAYS_INLINE_H
 
-#if (defined(__GNUC__) || defined(__clang__))
+#if defined(__GNUC__)
 #define ATH_FLATTEN [[gnu::flatten]]
-#else
-#define ATH_FLATTEN
-#endif
-
-#if (defined(__GNUC__) || defined(__clang__))
 #define ATH_ALWAYS_INLINE [[gnu::always_inline]] inline
-#else
-#define ATH_ALWAYS_INLINE inline
-#endif
-
-#if (defined(__GNUC__) || defined(__clang__))
 #define ATH_NOINLINE [[gnu::noinline]]
 #else
+#define ATH_FLATTEN
+#define ATH_ALWAYS_INLINE inline
 #define ATH_NOINLINE
 #endif
 
+
 #endif

MagneticField/MagFieldElements/src/AtlasFieldCache.cxx

@@ -14,6 +14,8 @@
 #include <cmath>
 #include <iostream>
 
+#include "CxxUtils/inline_hints.h"
+
 namespace {
 /* In Gaudi Units
  * Units.tesla
@@ -26,14 +28,12 @@ namespace {
 constexpr double defaultB = 0.1 * Gaudi::Units::gauss;
 }
 
-#if defined(__GNUC__)
 // We compile this package with optimization, even in debug builds; otherwise,
 // the heavy use of Eigen makes it too slow.  However, from here we may call
 // to out-of-line Eigen code that is linked from other DSOs; in that case,
 // it would not be optimized.  Avoid this by forcing all Eigen code
 // to be inlined here if possible.
-[[gnu::flatten]]
-#endif
+ATH_FLATTEN
 void
 MagField::AtlasFieldCache::getField(const double* ATH_RESTRICT xyz,
                                     double* ATH_RESTRICT bxyz,

Tracking/TrkDetDescr/TrkSurfaces/TrkSurfaces/Surface.icc

@@ -2,6 +2,7 @@
   Copyright (C) 2002-2022 CERN for the benefit of the ATLAS collaboration
 */
 
+#include "CxxUtils/inline_hints.h"
 namespace Trk {
 
 inline bool
@@ -263,20 +264,16 @@ Surface::associateLayer(const Layer& lay)
   m_associatedLayer = (&lay);
 }
 
-#if defined(__GNUC__)
-[[gnu::flatten]]
 // Avoid out-of-line-eigen calls
-#endif
+ATH_FLATTEN
 inline Amg::Transform3D
 Surface::inverseTransformHelper() const
 {
   return transform().inverse();
 }
 
-#if defined(__GNUC__)
-[[gnu::flatten]]
 // Avoid out-of-line-eigen calls
-#endif
+ATH_FLATTEN
 inline Amg::Vector3D
 Surface::inverseTransformMultHelper(const Amg::Vector3D& pos) const
 {

Tracking/TrkDetDescr/TrkSurfaces/src/PerigeeSurface.cxx

@@ -40,13 +40,13 @@ Trk::PerigeeSurface::PerigeeSurface(const Amg::Transform3D& tTransform)
     std::make_unique<Transforms>(tTransform, tTransform.translation(), s_xAxis);
 }
 
-#if defined(FLATTEN) && defined(__GNUC__)
+#if defined(FLATTEN)
 // We compile this function with optimization, even in debug builds; otherwise,
 // the heavy use of Eigen makes it too slow.  However, from here we may call
 // to out-of-line Eigen code that is linked from other DSOs; in that case,
 // it would not be optimized.  Avoid this by forcing all Eigen code
 // to be inlined here if possible.
-[[gnu::flatten]]
+ATH_FLATTEN
 #endif
 Trk::PerigeeSurface::PerigeeSurface(const PerigeeSurface& pesf)
   : Surface(pesf)
@@ -160,14 +160,12 @@ Trk::PerigeeSurface::localToGlobal(const Trk::LocalParameters& locpars) const
   return {0., 0., locpars[Trk::z0] + (center().z())};
 }
 
-#if defined(__GNUC__)
 // We compile this function with optimization, even in debug builds; otherwise,
 // the heavy use of Eigen makes it too slow.  However, from here we may call
 // to out-of-line Eigen code that is linked from other DSOs; in that case,
 // it would not be optimized.  Avoid this by forcing all Eigen code
 // to be inlined here if possible.
-[[gnu::flatten]]
-#endif
+ATH_FLATTEN
 // true local to global method/
 void
 Trk::PerigeeSurface::localToGlobal(const Amg::Vector2D& locpos,

Tracking/TrkFitter/TrkGaussianSumFilter/src/ElectronMaterialMixtureConvolution.cxx

@@ -35,10 +35,8 @@ dummyCacheElement(GsfMaterial::Combined& elem)
   elem.deltaCovariances[0] = AmgSymMatrix(5)::Zero();
 }
 
-#if defined(__GNUC__)
-[[gnu::flatten]]
 // Avoid out-of-line Eigen calls
-#endif
+ATH_FLATTEN
 inline void
 updateCacheElement(GsfMaterial::Combined& update,
                    size_t index,