Merge pull request #5512 from The-OpenROAD-Project-staging/gpl-thread…

…-non-determinism gpl: fix multithreading non-determinism
The-OpenROAD-Project · Aug 6, 2024 · 16ee4c3 · 16ee4c3
2 parents 3f36a37 + d360534
commit 16ee4c3
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Showing 2 changed files with 6 additions and 6 deletions.
diff --git a/src/gpl/src/nesterovBase.cpp b/src/gpl/src/nesterovBase.cpp
@@ -1961,8 +1961,10 @@ void NesterovBase::updateGradients(std::vector<FloatPoint>& sumGrads,
   debugPrint(
       log_, GPL, "updateGrad", 1, "DensityPenalty: {:g}", densityPenalty_);
 
-#pragma omp parallel for num_threads(nbc_->getNumThreads()) \
-    reduction(+ : wireLengthGradSum_, densityGradSum_, gradSum)
+  // TODO: This OpenMP parallel section is causing non-determinism. Consider
+  // revisiting this in the future to restore determinism.
+  //#pragma omp parallel for num_threads(nbc_->getNumThreads()) reduction(+ :
+  // wireLengthGradSum_, densityGradSum_, gradSum)
   for (size_t i = 0; i < gCells_.size(); i++) {
     GCell* gCell = gCells_.at(i);
     wireLengthGrads[i]

diff --git a/test/flow.tcl b/test/flow.tcl
@@ -39,6 +39,8 @@ read_verilog $synth_verilog
 link_design $top_module
 read_sdc $sdc_file
 
+set_thread_count [exec getconf _NPROCESSORS_ONLN]
+
 utl::metric "IFP::ord_version" [ord::openroad_git_describe]
 # Note that sta::network_instance_count is not valid after tapcells are added.
 utl::metric "IFP::instance_count" [sta::network_instance_count]
@@ -191,10 +193,6 @@ write_verilog $verilog_file
 ################################################################
 # Global routing
 
-# set multithreading for repair_antennas, check_antennas and
-# detailed_route
-set_thread_count [exec getconf _NPROCESSORS_ONLN]
-
 pin_access -bottom_routing_layer $min_routing_layer \
            -top_routing_layer $max_routing_layer