call fast path & reduce more flots

Signed-off-by: Felix Schlepper <felix.schlepper@cern.ch>

Author: f3sch

Detectors/ITSMFT/ITS/tracking/GPU/cuda/TrackingKernels.cu

@@ -205,7 +205,7 @@ GPUg() void __launch_bounds__(GPUThreads, MinBlocks.computeLayerCellNeighbours)
         continue;
       }
 
-      float chi2 = currentCellSeed.getPredictedChi2(nextCellSeed);
+      float chi2 = currentCellSeed.getPredictedChi2Fast(nextCellSeed);
       if (chi2 > maxChi2ClusterAttachment) {
         continue;
       }

Detectors/ITSMFT/ITS/tracking/include/ITStracking/MathUtils.h

@@ -68,7 +68,7 @@ GPUhdi() float computeCurvatureCentreX(float x1, float y1, float x2, float y2, f
   float dx21 = x2 - x1, dx32 = x3 - x2;
   if (o2::gpu::CAMath::Abs(dx21) < o2::its::constants::Tolerance ||
       o2::gpu::CAMath::Abs(dx32) < o2::its::constants::Tolerance) { // add small offset
-    x2 += 1e-4;
+    x2 += 1e-4f;
     dx21 = x2 - x1;
     dx32 = x3 - x2;
   }

Detectors/ITSMFT/ITS/tracking/src/TrackerTraits.cxx

@@ -521,7 +521,7 @@ void TrackerTraits<NLayers>::findCellsNeighbours(const int iteration)
               continue;
             }
 
-            float chi2 = currentCellSeed.getPredictedChi2(nextCellSeed);
+            float chi2 = currentCellSeed.getPredictedChi2Fast(nextCellSeed);
             if (chi2 > mTrkParams[iteration].MaxChi2ClusterAttachment) {
               continue;
             }