Merge pull request #45471 from fwyzard/fix_pixel_CPE_poisition_141x

Fix pixel CPE poisition
cms-sw · Jul 17, 2024 · 80f86b5 · 80f86b5
2 parents b08e6a8 + 785ff5d
commit 80f86b5
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Showing 4 changed files with 19 additions and 18 deletions.
diff --git a/DataFormats/TrackingRecHitSoA/BuildFile.xml b/DataFormats/TrackingRecHitSoA/BuildFile.xml
@@ -1,10 +1,11 @@
 <use name="alpaka"/>
 <use name="rootcore"/>
 <use name="eigen"/>
-<use name="DataFormats/SiPixelClusterSoA"/>
 <use name="DataFormats/Common"/>
-<use name="DataFormats/TrackerCommon" source_only="1"/>
+<use name="DataFormats/SiPixelClusterSoA"/>
 <use name="DataFormats/SoATemplate" source_only="1"/>
+<use name="DataFormats/TrackerCommon" source_only="1"/>
+<use name="Geometry/CommonTopologies" source_only="1"/>
 <use name="HeterogeneousCore/AlpakaInterface"/>
 <flags ALPAKA_BACKENDS="!serial"/>
 <export>

diff --git a/DataFormats/TrackingRecHitSoA/interface/TrackingRecHitsSoA.h b/DataFormats/TrackingRecHitSoA/interface/TrackingRecHitsSoA.h
@@ -5,8 +5,8 @@
 
 #include "DataFormats/SoATemplate/interface/SoALayout.h"
 #include "DataFormats/TrackingRecHitSoA/interface/SiPixelHitStatus.h"
+#include "Geometry/CommonTopologies/interface/SimplePixelTopology.h"
 #include "HeterogeneousCore/AlpakaInterface/interface/HistoContainer.h"
-#include "RecoLocalTracker/SiPixelRecHits/interface/pixelCPEforDevice.h"
 
 template <typename TrackerTraits>
 struct TrackingRecHitSoA {

diff --git a/RecoLocalTracker/SiPixelRecHits/interface/pixelCPEforDevice.h b/RecoLocalTracker/SiPixelRecHits/interface/pixelCPEforDevice.h
@@ -234,25 +234,24 @@ namespace pixelCPEforDevice {
     if (cp.minCol[ic] == 0 || cp.maxCol[ic] == uint32_t(detParams.nCols - 1))
       cp.ysize[ic] = -cp.ysize[ic];
 
-    // apply the lorentz offset correction
-    float xoff = 0.5f * float(detParams.nRows) * comParams.thePitchX;
-    float yoff = 0.5f * float(detParams.nCols) * comParams.thePitchY;
-
-    //correction for bigpixels for phase1
-    xoff = xoff + TrackerTraits::bigPixXCorrection * comParams.thePitchX;
-    yoff = yoff + TrackerTraits::bigPixYCorrection * comParams.thePitchY;
-
-    // apply the lorentz offset correction
-    auto xPos = detParams.shiftX + (comParams.thePitchX * 0.5f * float(mx)) - xoff;
-    auto yPos = detParams.shiftY + (comParams.thePitchY * 0.5f * float(my)) - yoff;
+    // Compute the position relative to the center of the module, taking into account the corrections for
+    // the Phase 1 big pixels, the module pitch, and the Lorentz shift.
+    // Use an explicit FMA instruction instead of simply (position * pitch + shift) to make sure that
+    // different compiler optimizations do not produce different code on different architectures.
+    float xPos = std::fmaf(0.5f * ((float)mx - (float)detParams.nRows) - TrackerTraits::bigPixXCorrection,
+                           comParams.thePitchX,
+                           detParams.shiftX);
+    float yPos = std::fmaf(0.5f * ((float)my - (float)detParams.nCols) - TrackerTraits::bigPixYCorrection,
+                           comParams.thePitchY,
+                           detParams.shiftY);
 
     float cotalpha = 0, cotbeta = 0;
 
     computeAnglesFromDet(detParams, xPos, yPos, cotalpha, cotbeta);
 
     auto thickness = detParams.isBarrel ? comParams.theThicknessB : comParams.theThicknessE;
 
-    auto xcorr = correction(cp.maxRow[ic] - cp.minRow[ic],
+    auto xCorr = correction(cp.maxRow[ic] - cp.minRow[ic],
                             cp.q_f_X[ic],
                             cp.q_l_X[ic],
                             llxl,
@@ -264,7 +263,7 @@ namespace pixelCPEforDevice {
                             TrackerTraits::isBigPixX(cp.minRow[ic]),
                             TrackerTraits::isBigPixX(cp.maxRow[ic]));
 
-    auto ycorr = correction(cp.maxCol[ic] - cp.minCol[ic],
+    auto yCorr = correction(cp.maxCol[ic] - cp.minCol[ic],
                             cp.q_f_Y[ic],
                             cp.q_l_Y[ic],
                             llyl,
@@ -276,8 +275,8 @@ namespace pixelCPEforDevice {
                             TrackerTraits::isBigPixY(cp.minCol[ic]),
                             TrackerTraits::isBigPixY(cp.maxCol[ic]));
 
-    cp.xpos[ic] = xPos + xcorr;
-    cp.ypos[ic] = yPos + ycorr;
+    cp.xpos[ic] = xPos + xCorr;
+    cp.ypos[ic] = yPos + yCorr;
   }
 
   template <typename TrackerTraits>

diff --git a/RecoTracker/PixelSeeding/plugins/alpaka/CAPixelDoubletsAlgos.h b/RecoTracker/PixelSeeding/plugins/alpaka/CAPixelDoubletsAlgos.h
@@ -10,6 +10,7 @@
 #include <alpaka/alpaka.hpp>
 
 #include "DataFormats/Math/interface/approx_atan2.h"
+#include "DataFormats/SiPixelClusterSoA/interface/ClusteringConstants.h"
 #include "DataFormats/TrackingRecHitSoA/interface/TrackingRecHitsSoA.h"
 #include "Geometry/CommonTopologies/interface/SimplePixelTopology.h"
 #include "HeterogeneousCore/AlpakaInterface/interface/VecArray.h"