From 1f4804452c05c57308979bf090305c7c882f92c9 Mon Sep 17 00:00:00 2001
From: Robin Burchell <robin+qt@viroteck.net>
Date: Tue, 28 Feb 2012 20:56:14 +0100
Subject: Copy Qt 4's QString hash algorithm.
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We must do this the same way we do all other hash algorithms for fair
comparison, as otherwise, the call to the PLT unfairly penalises
QHash<QString>'s results, as it's in a different shared object.

Change-Id: I69c891f5a97dcccdfcfbdbf32796f86242a42963
Reviewed-by: João Abecasis <joao.abecasis@nokia.com>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
---
 tests/benchmarks/corelib/tools/qhash/main.cpp      |  7 +++++--
 tests/benchmarks/corelib/tools/qhash/main.h        | 11 +++++++++++
 tests/benchmarks/corelib/tools/qhash/outofline.cpp | 18 ++++++++++++++++--
 3 files changed, 32 insertions(+), 4 deletions(-)

(limited to 'tests/benchmarks/corelib/tools')

diff --git a/tests/benchmarks/corelib/tools/qhash/main.cpp b/tests/benchmarks/corelib/tools/qhash/main.cpp
index 7a871b455c..62384fbaa7 100644
--- a/tests/benchmarks/corelib/tools/qhash/main.cpp
+++ b/tests/benchmarks/corelib/tools/qhash/main.cpp
@@ -138,8 +138,11 @@ void tst_QHash::data()
 void tst_QHash::qhash_qt4()
 {
     QFETCH(QStringList, items);
-    QStringList realitems = items; // for copy/paste ease between benchmarks
-    QHash<QString, int> hash;
+    QHash<Qt4String, int> hash;
+
+    QList<Qt4String> realitems;
+    foreach (const QString &s, items)
+        realitems.append(s);
 
     QBENCHMARK {
         for (int i = 0, n = realitems.size(); i != n; ++i) {
diff --git a/tests/benchmarks/corelib/tools/qhash/main.h b/tests/benchmarks/corelib/tools/qhash/main.h
index c4cf94e190..3d193b5e40 100644
--- a/tests/benchmarks/corelib/tools/qhash/main.h
+++ b/tests/benchmarks/corelib/tools/qhash/main.h
@@ -41,6 +41,17 @@
 
 #include <QString>
 
+struct Qt4String : QString
+{
+    Qt4String() {}
+    Qt4String(const QString &s) : QString(s) {}
+};
+
+QT_BEGIN_NAMESPACE
+uint qHash(const Qt4String &);
+QT_END_NAMESPACE
+
+
 struct String : QString
 {
     String() {}
diff --git a/tests/benchmarks/corelib/tools/qhash/outofline.cpp b/tests/benchmarks/corelib/tools/qhash/outofline.cpp
index 162c604a35..8adaa0a04f 100644
--- a/tests/benchmarks/corelib/tools/qhash/outofline.cpp
+++ b/tests/benchmarks/corelib/tools/qhash/outofline.cpp
@@ -41,6 +41,22 @@
 
 #include "main.h"
 
+QT_BEGIN_NAMESPACE
+
+uint qHash(const Qt4String &str)
+{
+    int n = str.length();
+    const QChar *p = str.unicode();
+    uint h = 0;
+
+    while (n--) {
+        h = (h << 4) + (*p++).unicode();
+        h ^= (h & 0xf0000000) >> 23;
+        h &= 0x0fffffff;
+    }
+    return h;
+}
+
 static void doHash(const unsigned short *p, uint &h)
 {
 #if 1
@@ -67,8 +83,6 @@ static void doHash(const unsigned short *p, uint &h)
 #endif
 }
 
-QT_BEGIN_NAMESPACE
-
 uint qHash(const String &str)
 {
     const unsigned short *p = (unsigned short *)str.constData();
-- 
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