From 08ac892e4e491dfb553984bea7787724d4347c81 Mon Sep 17 00:00:00 2001
From: Niko Savola <nikosavola@taaraconnect.com>
Date: Wed, 3 Jun 2026 14:55:49 +0300
Subject: [PATCH 1/2] Leverage execution policies in `dbShapes` and PLC
 decomposition

---
 src/db/db/dbPLCConvexDecomposition.cc | 12 ++++++++++--
 src/db/db/dbShapes.cc                 | 10 +++++++++-
 2 files changed, 19 insertions(+), 3 deletions(-)

diff --git a/src/db/db/dbPLCConvexDecomposition.cc b/src/db/db/dbPLCConvexDecomposition.cc
index 95633fb3a..9e1b50914 100644
--- a/src/db/db/dbPLCConvexDecomposition.cc
+++ b/src/db/db/dbPLCConvexDecomposition.cc
@@ -30,6 +30,14 @@
 #include <memory>
 #include <vector>
 #include <map>
+#include <algorithm>
+
+#if defined(__cpp_lib_execution)
+#include <execution>
+#define PARALLEL_EXEC_POLICY std::execution::par,
+#else
+#define PARALLEL_EXEC_POLICY
+#endif
 
 // #define DEBUG_DUMP_ESSENTIAL_EDGES
 
@@ -269,7 +277,7 @@ ConvexDecomposition::hertel_mehlhorn_decomposition (Triangulation &tris, const C
 
   if (! new_points.empty ()) {
 
-    std::sort (new_points.begin (), new_points.end (), less_compare_func<db::DPoint> ());
+    std::sort (PARALLEL_EXEC_POLICY new_points.begin (), new_points.end (), less_compare_func<db::DPoint> ());
     new_points.erase (std::unique (new_points.begin (), new_points.end (), equal_compare_func<db::DPoint> ()), new_points.end ());
 
     //  Insert the new points and make connections
@@ -332,7 +340,7 @@ ConvexDecomposition::hertel_mehlhorn_decomposition (Triangulation &tris, const C
         }
       }
 
-      std::sort (sorted_edges.begin (), sorted_edges.end (), SortAngleAndEdgesByEdgeLength ());
+      std::sort (PARALLEL_EXEC_POLICY sorted_edges.begin (), sorted_edges.end (), SortAngleAndEdgesByEdgeLength ());
 
       for (auto i = sorted_edges.end (); i != sorted_edges.begin (); ) {
         --i;
diff --git a/src/db/db/dbShapes.cc b/src/db/db/dbShapes.cc
index 8176df950..dbfca4a90 100644
--- a/src/db/db/dbShapes.cc
+++ b/src/db/db/dbShapes.cc
@@ -30,6 +30,14 @@
 #include "dbLayout.h"
 
 #include <limits>
+#include <algorithm>
+
+#if defined(__cpp_lib_execution)
+#include <execution>
+#define PARALLEL_EXEC_POLICY std::execution::par,
+#else
+#define PARALLEL_EXEC_POLICY
+#endif
 
 namespace db
 {
@@ -111,7 +119,7 @@ layer_op<Sh, StableTag>::erase (Shapes *shapes)
     std::vector<bool> done;
     done.resize (m_shapes.size (), false);
 
-    std::sort (m_shapes.begin (), m_shapes.end ());
+    std::sort (PARALLEL_EXEC_POLICY m_shapes.begin (), m_shapes.end ());
 
     typename std::vector<Sh>::const_iterator s_begin = m_shapes.begin ();
     typename std::vector<Sh>::const_iterator s_end = m_shapes.end ();

From 6f167d2dd1731c84aeeaebc9001119741b5867db Mon Sep 17 00:00:00 2001
From: Niko Savola <nikomsavola@gmail.com>
Date: Fri, 25 Sep 2026 10:42:32 +0300
Subject: [PATCH 2/2] Include execution before checking its feature macro

---
 src/db/db/dbPLCConvexDecomposition.cc | 7 ++++++-
 src/db/db/dbShapes.cc                 | 7 ++++++-
 2 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/src/db/db/dbPLCConvexDecomposition.cc b/src/db/db/dbPLCConvexDecomposition.cc
index 9e1b50914..ca7f611dc 100644
--- a/src/db/db/dbPLCConvexDecomposition.cc
+++ b/src/db/db/dbPLCConvexDecomposition.cc
@@ -32,8 +32,13 @@
 #include <map>
 #include <algorithm>
 
+#if __cplusplus >= 201703L
+  #if __has_include(<execution>)
+    #include <execution>
+  #endif
+#endif
+
 #if defined(__cpp_lib_execution)
-#include <execution>
 #define PARALLEL_EXEC_POLICY std::execution::par,
 #else
 #define PARALLEL_EXEC_POLICY
diff --git a/src/db/db/dbShapes.cc b/src/db/db/dbShapes.cc
index dbfca4a90..deb9fe916 100644
--- a/src/db/db/dbShapes.cc
+++ b/src/db/db/dbShapes.cc
@@ -32,8 +32,13 @@
 #include <limits>
 #include <algorithm>
 
+#if __cplusplus >= 201703L
+  #if __has_include(<execution>)
+    #include <execution>
+  #endif
+#endif
+
 #if defined(__cpp_lib_execution)
-#include <execution>
 #define PARALLEL_EXEC_POLICY std::execution::par,
 #else
 #define PARALLEL_EXEC_POLICY