Use on-disk compilation unit if available

If we succeeded in saving the compilation unit to disk, then attempt to use it
right away. This replaces the C++ heap usage for the compilation unit data as
well as the anonymous allocated executable memory with file-backed mmap'ed
memory. That means the memory can be discarded when overall availability is low
and paged in on-demand.

Change-Id: Ide1b1e11752d861eb049a99a26ca12cec5e2502e
Reviewed-by: Ulf Hermann <ulf.hermann@qt.io>

1 files changed, 7 insertions, 2 deletions

diff --git a/tests/auto/qml/qqmllanguage/tst_qqmllanguage.cpp b/tests/auto/qml/qqmllanguage/tst_qqmllanguage.cpp
index 1a035be5e0..f32051a26a 100644
--- a/tests/auto/qml/qqmllanguage/tst_qqmllanguage.cpp
+++ b/tests/auto/qml/qqmllanguage/tst_qqmllanguage.cpp
@@ -2118,8 +2118,13 @@ void tst_qqmllanguage::scriptStringWithoutSourceCode()
         QQmlTypeData *td = eng->typeLoader.getType(url);
         Q_ASSERT(td);
 
-        const QV4::CompiledData::Unit *qmlUnit = td->compilationUnit()->data;
-        Q_ASSERT(qmlUnit);
+        const QV4::CompiledData::Unit *readOnlyQmlUnit = td->compilationUnit()->data;
+        Q_ASSERT(readOnlyQmlUnit);
+        QV4::CompiledData::Unit *qmlUnit = reinterpret_cast<QV4::CompiledData::Unit *>(malloc(readOnlyQmlUnit->unitSize));
+        memcpy(qmlUnit, readOnlyQmlUnit, readOnlyQmlUnit->unitSize);
+        qmlUnit->flags &= ~QV4::CompiledData::Unit::StaticData;
+        td->compilationUnit()->data = qmlUnit;
+
         const QV4::CompiledData::Object *rootObject = qmlUnit->objectAt(qmlUnit->indexOfRootObject);
         QCOMPARE(qmlUnit->stringAt(rootObject->inheritedTypeNameIndex), QString("MyTypeObject"));
         quint32 i;