diff options
author | Lars Knoll <lars.knoll@qt.io> | 2018-04-25 15:19:54 +0200 |
---|---|---|
committer | Simon Hausmann <simon.hausmann@qt.io> | 2018-04-26 06:51:31 +0000 |
commit | fb027435f597d55b9e72465036cb0daa2b272ec0 (patch) | |
tree | 6fa6ea1647d7ea0947e7d153c22a36bc98667ad9 /src/qml | |
parent | 950de04322191c16c3066707889b17b0f5eb2ee6 (diff) |
Only create CallContext objects for bindings that might be signal handlers
Creating the callcontext for all bindings causes a 15% performance
regression in both of the moving images benchmarks of qmlbench.
But in most cases, we know that a binding can't be a signal handler,
as those always have to start with 'on'. Take this into account
and avoid creating the context for most binding expressions.
Task-number: QTBUG-67782
Task-number: QTBUG-67783
Change-Id: I9a25cb916e374c7d03693e49646ca28853c6ba54
Reviewed-by: Simon Hausmann <simon.hausmann@qt.io>
Diffstat (limited to 'src/qml')
-rw-r--r-- | src/qml/compiler/qv4codegen.cpp | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/src/qml/compiler/qv4codegen.cpp b/src/qml/compiler/qv4codegen.cpp index 8ada1d505e..c281275da1 100644 --- a/src/qml/compiler/qv4codegen.cpp +++ b/src/qml/compiler/qv4codegen.cpp @@ -2104,9 +2104,14 @@ int Codegen::defineFunction(const QString &name, AST::Node *ast, _context->addLocalVar(QStringLiteral("arguments"), Context::VariableDeclaration, AST::VariableDeclaration::FunctionScope); bool allVarsEscape = _context->hasWith || _context->hasTry || _context->hasDirectEval; - if (_context->compilationMode == QmlBinding // we don't really need this for bindings, but we do for signal handlers, and we don't know if the code is a signal handler or not. - || (!_context->canUseSimpleCall() && _context->compilationMode != GlobalCode && - (_context->compilationMode != EvalCode || _context->isStrict))) { + bool needsCallContext = false; + const QLatin1String exprForOn("expression for on"); + if (!_context->canUseSimpleCall() && _context->compilationMode != GlobalCode && (_context->compilationMode != EvalCode || _context->isStrict)) + needsCallContext = true; + else if (_context->compilationMode == QmlBinding && name.length() > exprForOn.size() && name.startsWith(exprForOn) && name.at(exprForOn.size()).isUpper()) + // we don't really need this for bindings, but we do for signal handlers, and we don't know if the code is a signal handler or not. + needsCallContext = true; + if (needsCallContext) { Instruction::CreateCallContext createContext; bytecodeGenerator->addInstruction(createContext); } |