Boost performance of QChar::isSpace

Make it inline; add fast checks for typical spaces;
add fallback function that uses the fastcall calling
convention.

On ia32, this change makes isSpace ~340x faster for
ascii spaces, ~170x faster for non-space ascii
characters, and ~1.3x faster for non-ascii characters.

Note that this change is NOT binary compatible.

Also add an autotest with expected results from
before the optimization, to ensure that the behavior
is the same.

Change-Id: I9438d0ad3c9ba2e80560c4bee7eed05115265798
Reviewed-on: http://codereview.qt-project.org/4905
Reviewed-by: Qt Sanity Bot <qt_sanity_bot@ovi.com>
Reviewed-by: Lars Knoll <lars.knoll@nokia.com>

1 files changed, 21 insertions, 0 deletions

diff --git a/tests/auto/corelib/tools/qchar/tst_qchar.cpp b/tests/auto/corelib/tools/qchar/tst_qchar.cpp
index f16d32a4f9..195abcd578 100644
--- a/tests/auto/corelib/tools/qchar/tst_qchar.cpp
+++ b/tests/auto/corelib/tools/qchar/tst_qchar.cpp
@@ -82,6 +82,8 @@ private slots:
     void isPrint();
     void isUpper();
     void isLower();
+    void isSpace_data();
+    void isSpace();
     void isTitle();
     void category();
     void direction();
@@ -335,6 +337,25 @@ void tst_QChar::isLower()
     }
 }
 
+void tst_QChar::isSpace_data()
+{
+    QTest::addColumn<ushort>("ucs");
+    QTest::addColumn<bool>("expected");
+
+    for (ushort ucs = 0; ucs < 256; ++ucs) {
+        bool isSpace = (ucs <= 0x0D && ucs >= 0x09) || ucs == 0x20 || ucs == 0xA0;
+        QString tag = QString::fromLatin1("0x%0").arg(QString::number(ucs, 16));
+        QTest::newRow(tag.toLatin1()) << ucs << isSpace;
+    }
+}
+
+void tst_QChar::isSpace()
+{
+    QFETCH(ushort, ucs);
+    QFETCH(bool, expected);
+    QCOMPARE(QChar(ucs).isSpace(), expected);
+}
+
 void tst_QChar::isTitle()
 {
     for (uint codepoint = 0; codepoint <= UNICODE_LAST_CODEPOINT; ++codepoint) {