From b116fe452c42acc72afdebe4aba3ecdb83a2fa25 Mon Sep 17 00:00:00 2001
From: Niko Savola <nikosavola@taaraconnect.com>
Date: Wed, 3 Jun 2026 10:05:30 +0300
Subject: [PATCH 1/2] Use `std::execution::par` in `dbEdgeProcessor` and
 `dbPolygonTools` sorts

---
 src/db/db/dbEdgeProcessor.cc | 11 +++++++++--
 src/db/db/dbPolygonTools.cc  | 11 +++++++++--
 2 files changed, 18 insertions(+), 4 deletions(-)

diff --git a/src/db/db/dbEdgeProcessor.cc b/src/db/db/dbEdgeProcessor.cc
index b50f83cf4..1b5a08391 100644
--- a/src/db/db/dbEdgeProcessor.cc
+++ b/src/db/db/dbEdgeProcessor.cc
@@ -29,6 +29,13 @@
 #include "tlProgress.h"
 #include "gsi.h"
 
+#if defined(__cpp_lib_execution)
+#include <execution>
+#define PARALLEL_EXEC_POLICY std::execution::par,
+#else
+#define PARALLEL_EXEC_POLICY
+#endif
+
 #include <vector>
 #include <deque>
 #include <memory>
@@ -2237,7 +2244,7 @@ EdgeProcessor::redo_or_process (const std::vector<std::pair<db::EdgeSink *, db::
   } else {
 
     //  step 2: find intersections
-    std::sort (mp_work_edges->begin (), mp_work_edges->end (), edge_ymin_compare<db::Coord> ());
+    std::sort (PARALLEL_EXEC_POLICY mp_work_edges->begin (), mp_work_edges->end (), edge_ymin_compare<db::Coord> ());
 
     y = edge_ymin ((*mp_work_edges) [0]);
     future = mp_work_edges->begin ();
@@ -2422,7 +2429,7 @@ EdgeProcessor::redo_or_process (const std::vector<std::pair<db::EdgeSink *, db::
   gs.reset ();
   gs.reserve (n_props);
 
-  std::sort (mp_work_edges->begin (), mp_work_edges->end (), edge_ymin_compare<db::Coord> ());
+  std::sort (PARALLEL_EXEC_POLICY mp_work_edges->begin (), mp_work_edges->end (), edge_ymin_compare<db::Coord> ());
 
   y = edge_ymin ((*mp_work_edges) [0]);
 
diff --git a/src/db/db/dbPolygonTools.cc b/src/db/db/dbPolygonTools.cc
index a5a63cd6c..228a368bf 100644
--- a/src/db/db/dbPolygonTools.cc
+++ b/src/db/db/dbPolygonTools.cc
@@ -28,6 +28,13 @@
 #include "tlLog.h"
 #include "tlInt128Support.h"
 
+#if defined(__cpp_lib_execution)
+#include <execution>
+#define PARALLEL_EXEC_POLICY std::execution::par,
+#else
+#define PARALLEL_EXEC_POLICY
+#endif
+
 #include <algorithm>
 #include <cmath>
 #include <limits>
@@ -1838,7 +1845,7 @@ rasterize_impl (const db::polygon<C> &polygon, db::area_map<C> &am)
   }
 
   //  sort edges
-  std::sort (edges.begin (), edges.end (), db::edge_ymin_compare<C> ());
+  std::sort (PARALLEL_EXEC_POLICY edges.begin (), edges.end (), db::edge_ymin_compare<C> ());
 
   typename std::vector <edge_type>::iterator c = edges.begin ();
 
@@ -2761,7 +2768,7 @@ decompose_convex_to_trapezoids (const db::SimplePolygon &sp, bool horizontal, db
     }
   }
 
-  std::sort (edges.begin (), edges.end (), db::edge_ymin_compare<db::Coord> ());
+  std::sort (PARALLEL_EXEC_POLICY edges.begin (), edges.end (), db::edge_ymin_compare<db::Coord> ());
 
   db::Coord y = db::edge_ymin (edges.front ());
 

From 7e6119c777fbe083c8ca7b31c79c76de12c5eb3c Mon Sep 17 00:00:00 2001
From: Niko Savola <nikosavola@taaraconnect.com>
Date: Thu, 4 Jun 2026 10:30:27 +0000
Subject: [PATCH 2/2] Make TBB linking conditional and improve backward
 compatibility of execution header guards

---
 src/db/db/db.pro             |  4 ++++
 src/db/db/dbEdgeProcessor.cc | 17 +++++++++++------
 src/db/db/dbPolygonTools.cc  | 17 +++++++++++------
 3 files changed, 26 insertions(+), 12 deletions(-)

diff --git a/src/db/db/db.pro b/src/db/db/db.pro
index d316c1c60..1c1285342 100644
--- a/src/db/db/db.pro
+++ b/src/db/db/db.pro
@@ -454,3 +454,7 @@ INCLUDEPATH += $$TL_INC $$GSI_INC
 DEPENDPATH += $$TL_INC $$GSI_INC
 LIBS += -L$$DESTDIR -lklayout_tl -lklayout_gsi
 
+packagesExist(tbb) {
+    LIBS += -ltbb
+}
+
diff --git a/src/db/db/dbEdgeProcessor.cc b/src/db/db/dbEdgeProcessor.cc
index 1b5a08391..a9f73666b 100644
--- a/src/db/db/dbEdgeProcessor.cc
+++ b/src/db/db/dbEdgeProcessor.cc
@@ -1,3 +1,14 @@
+#if __cplusplus >= 201703L
+  #if __has_include(<execution>)
+    #include <execution>
+  #endif
+#endif
+
+#if defined(__cpp_lib_execution)
+#define PARALLEL_EXEC_POLICY std::execution::par,
+#else
+#define PARALLEL_EXEC_POLICY
+#endif
 
 /*
 
@@ -29,12 +40,6 @@
 #include "tlProgress.h"
 #include "gsi.h"
 
-#if defined(__cpp_lib_execution)
-#include <execution>
-#define PARALLEL_EXEC_POLICY std::execution::par,
-#else
-#define PARALLEL_EXEC_POLICY
-#endif
 
 #include <vector>
 #include <deque>
diff --git a/src/db/db/dbPolygonTools.cc b/src/db/db/dbPolygonTools.cc
index 228a368bf..849e0a154 100644
--- a/src/db/db/dbPolygonTools.cc
+++ b/src/db/db/dbPolygonTools.cc
@@ -1,3 +1,14 @@
+#if __cplusplus >= 201703L
+  #if __has_include(<execution>)
+    #include <execution>
+  #endif
+#endif
+
+#if defined(__cpp_lib_execution)
+#define PARALLEL_EXEC_POLICY std::execution::par,
+#else
+#define PARALLEL_EXEC_POLICY
+#endif
 
 /*
 
@@ -28,12 +39,6 @@
 #include "tlLog.h"
 #include "tlInt128Support.h"
 
-#if defined(__cpp_lib_execution)
-#include <execution>
-#define PARALLEL_EXEC_POLICY std::execution::par,
-#else
-#define PARALLEL_EXEC_POLICY
-#endif
 
 #include <algorithm>
 #include <cmath>