Use a vector instead of a set to hold build graph nodes

The set even loses in the purely instruction count based metric employed
in our benchmarking tool.
A quick test with a larger project shows no performance advantage of the
set either.

========== Performance data for Rule Execution ==========
    Old instruction count: 3485129349
    New instruction count: 3456144664
    Relative change: -1 %
    Old peak memory usage: 17597368 Bytes
    New peak memory usage: 16750392 Bytes
    Relative change: -5 %
========== Performance data for Null Build ==========
    Old instruction count: 451359636
    New instruction count: 439286904
    Relative change: -3 %
    Old peak memory usage: 13141728 Bytes
    New peak memory usage: 12246952 Bytes
    Relative change: -7 %

Change-Id: I8fead52f728e7078dade1f021fdb28017a17fe43
Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>

1 files changed, 5 insertions, 8 deletions

diff --git a/src/lib/corelib/buildgraph/nodeset.cpp b/src/lib/corelib/buildgraph/nodeset.cpp
index 3b3f2b781..faeba732c 100644
--- a/src/lib/corelib/buildgraph/nodeset.cpp
+++ b/src/lib/corelib/buildgraph/nodeset.cpp
@@ -48,26 +48,23 @@
 namespace qbs {
 namespace Internal {
 
-NodeSet::NodeSet()
-    : d(new NodeSetData)
-{
-}
-
 NodeSet &NodeSet::unite(const NodeSet &other)
 {
-    d->m_data.insert(other.begin(), other.end());
+    for (auto node = other.m_data.cbegin(); node != other.m_data.cend(); ++node)
+        insert(*node);
     return *this;
 }
 
 void NodeSet::remove(BuildGraphNode *node)
 {
-    d->m_data.erase(node);
+    m_data.removeOne(node);
 }
 
 void NodeSet::load(PersistentPool &pool)
 {
     clear();
     int i = pool.load<int>();
+    reserve(i);
     for (; --i >= 0;) {
         const auto t = pool.load<quint8>();
         BuildGraphNode *node = 0;
@@ -80,7 +77,7 @@ void NodeSet::load(PersistentPool &pool)
             break;
         }
         QBS_CHECK(node);
-        insert(node);
+        m_data << node;
     }
 }