From 5eb52e8a8fd3b597fd991812c3c90e2698dbe71f Mon Sep 17 00:00:00 2001
From: Peter Gadfort <gadfort@zeroasic.com>
Date: Mon, 23 Sep 2024 16:24:41 -0400
Subject: [PATCH] tap: avoid iterating over insts multiple times when placing
 tapcells

Signed-off-by: Peter Gadfort <gadfort@zeroasic.com>
---
 src/tap/include/tap/tapcell.h | 17 ++++++++++++++++-
 src/tap/src/tapcell.cpp       | 32 +++++++++++++++++++-------------
 2 files changed, 35 insertions(+), 14 deletions(-)

diff --git a/src/tap/include/tap/tapcell.h b/src/tap/include/tap/tapcell.h
index 05d721675fe..a7ea8adfa7c 100644
--- a/src/tap/include/tap/tapcell.h
+++ b/src/tap/include/tap/tapcell.h
@@ -36,6 +36,7 @@
 #include <boost/polygon/polygon.hpp>
 
 #include "odb/db.h"
+#include "odb/geom_boost.h"
 
 namespace ord {
 class OpenRoad;
@@ -163,6 +164,19 @@ class Tapcell
   using Polygon90 = boost::polygon::polygon_90_with_holes_data<int>;
   using CornerMap = std::map<odb::dbRow*, std::set<odb::dbInst*>>;
 
+  struct InstIndexableGetter
+  {
+    using result_type = odb::Rect;
+    odb::Rect operator()(odb::dbInst* inst) const
+    {
+      return inst->getBBox()->getBox();
+    }
+  };
+  using InstTree
+      = boost::geometry::index::rtree<odb::dbInst*,
+                                      boost::geometry::index::quadratic<16>,
+                                      InstIndexableGetter>;
+
   std::vector<odb::dbBox*> findBlockages();
   bool checkSymmetry(odb::dbMaster* master, const odb::dbOrientType& ori);
   odb::dbInst* makeInstance(odb::dbBlock* block,
@@ -190,7 +204,8 @@ class Tapcell
                     int dist,
                     odb::dbRow* row,
                     bool is_edge,
-                    bool disallow_one_site_gaps);
+                    bool disallow_one_site_gaps,
+                    const InstTree& fixed_instances);
 
   int defaultDistance() const;
 
diff --git a/src/tap/src/tapcell.cpp b/src/tap/src/tapcell.cpp
index 627436e0f2e..3335e286589 100644
--- a/src/tap/src/tapcell.cpp
+++ b/src/tap/src/tapcell.cpp
@@ -160,11 +160,23 @@ int Tapcell::placeTapcells(odb::dbMaster* tapcell_master,
     edge_rows.insert(rows.begin(), rows.end());
   }
 
+  std::vector<odb::dbInst*> fixed_insts;
+  for (auto* inst : db_->getChip()->getBlock()->getInsts()) {
+    if (inst->isFixed()) {
+      fixed_insts.push_back(inst);
+    }
+  }
+  InstTree instancetree(fixed_insts.begin(), fixed_insts.end());
+
   int inst = 0;
   for (auto* row : db_->getChip()->getBlock()->getRows()) {
     const bool is_edge = edge_rows.find(row) != edge_rows.end();
-    inst += placeTapcells(
-        tapcell_master, dist, row, is_edge, disallow_one_site_gaps);
+    inst += placeTapcells(tapcell_master,
+                          dist,
+                          row,
+                          is_edge,
+                          disallow_one_site_gaps,
+                          instancetree);
   }
   logger_->info(utl::TAP, 5, "Inserted {} tapcells.", inst);
   return inst;
@@ -174,7 +186,8 @@ int Tapcell::placeTapcells(odb::dbMaster* tapcell_master,
                            const int dist,
                            odb::dbRow* row,
                            const bool is_edge,
-                           const bool disallow_one_site_gaps)
+                           const bool disallow_one_site_gaps,
+                           const InstTree& fixed_instances)
 {
   if (row->getSite()->getName() != tapcell_master->getSite()->getName()) {
     return 0;
@@ -202,16 +215,9 @@ int Tapcell::placeTapcells(odb::dbMaster* tapcell_master,
 
   const odb::Rect row_bb = row->getBBox();
 
-  std::set<odb::dbInst*> row_insts;
-  for (auto* inst : db_->getChip()->getBlock()->getInsts()) {
-    if (!inst->isFixed()) {
-      continue;
-    }
-
-    if (row_bb.contains(inst->getBBox()->getBox())) {
-      row_insts.insert(inst);
-    }
-  }
+  std::set<odb::dbInst*> row_insts(
+      fixed_instances.qbegin(boost::geometry::index::covered_by(row_bb)),
+      fixed_instances.qend());
 
   const int llx = row_bb.xMin();
   const int urx = row_bb.xMax();