From: Alex Lorenz <arphaman@gmail.com>
Date: Tue, 29 Jul 2014 21:42:24 +0000 (+0000)
Subject: Coverage: improve efficiency of the counter propagation to the expansion regions.
X-Git-Url: http://plrg.eecs.uci.edu/git/?p=oota-llvm.git;a=commitdiff_plain;h=5819748a2df0c976f88a3918a0293ae5e5cd5617

Coverage: improve efficiency of the counter propagation to the expansion regions.

This patch reduces the complexity of the two inner loops in order to speed up
the loading of coverage data for very large functions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214228 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/ProfileData/CoverageMappingReader.cpp b/lib/ProfileData/CoverageMappingReader.cpp
index 21acae1bbdd..75ade55e2ed 100644
--- a/lib/ProfileData/CoverageMappingReader.cpp
+++ b/lib/ProfileData/CoverageMappingReader.cpp
@@ -251,15 +251,19 @@ std::error_code RawCoverageMappingReader::read(CoverageMappingRecord &Record) {
   // from the expanded file.
   // Perform multiple passes to correctly propagate the counters through
   // all the nested expansion regions.
+  SmallVector<CounterMappingRegion *, 8> FileIDExpansionRegionMapping;
+  FileIDExpansionRegionMapping.resize(VirtualFileMapping.size(), nullptr);
   for (unsigned Pass = 1, S = VirtualFileMapping.size(); Pass < S; ++Pass) {
-    for (auto &I : MappingRegions) {
-      if (I.Kind == CounterMappingRegion::ExpansionRegion) {
-        for (const auto &J : MappingRegions) {
-          if (J.FileID == I.ExpandedFileID) {
-            I.Count = J.Count;
-            break;
-          }
-        }
+    for (auto &R : MappingRegions) {
+      if (R.Kind != CounterMappingRegion::ExpansionRegion)
+        continue;
+      assert(!FileIDExpansionRegionMapping[R.ExpandedFileID]);
+      FileIDExpansionRegionMapping[R.ExpandedFileID] = &R;
+    }
+    for (auto &R : MappingRegions) {
+      if (FileIDExpansionRegionMapping[R.FileID]) {
+        FileIDExpansionRegionMapping[R.FileID]->Count = R.Count;
+        FileIDExpansionRegionMapping[R.FileID] = nullptr;
       }
     }
   }