diff options
author | Erik Verbruggen <erik.verbruggen@qt.io> | 2018-03-19 13:14:13 +0100 |
---|---|---|
committer | Erik Verbruggen <erik.verbruggen@qt.io> | 2018-03-20 09:38:27 +0000 |
commit | 22b13921f8067f8a93164875a4ad59bed85b0400 (patch) | |
tree | 4422ba520a96c7c41466426b3ae26ac15816b52d /src/qml/compiler | |
parent | 971292128b292052ef935da67a5d04fb5a3753f4 (diff) |
Handle function expressions as signal handlers
There are two ways to use function expressions on the right-hand side
of bindings:
property var somethingPressed
somethingPressed: function() { /* ..press something else.. */ }
signal buttonPressed
onButtonPressed: function() { /* ..handle buttonPress.. */ }
In the former case, it declares a property that holds a function. So on
initialization, the right-hand side of the binding returns a closure
that gets assigned to the property 'somethingPressed'.
In the latter case, the signal handler is explicitly marked as a
function for clarity. So, the handler should not be returning the
closure, but the handler should *be* the closure.
In general, it is not possible to detect if the left-hand side is a
property or a signal handler when generating QML cache files ahead of
time. So for this case, we mark the function as only returning a
closure. Then when instantiating the object, we check if it is a signal
handler, and if the handler is marked as only returning a closure. If
so, we set that closure to be the signal handler.
Task-number: QTBUG-57043
Task-number: QTBUG-50328
Change-Id: I3008ddd847e30b7d0adef07344a326f84d85f1ba
Reviewed-by: Simon Hausmann <simon.hausmann@qt.io>
Diffstat (limited to 'src/qml/compiler')
-rw-r--r-- | src/qml/compiler/qv4codegen.cpp | 8 | ||||
-rw-r--r-- | src/qml/compiler/qv4compileddata_p.h | 2 | ||||
-rw-r--r-- | src/qml/compiler/qv4compiler.cpp | 4 | ||||
-rw-r--r-- | src/qml/compiler/qv4compilercontext_p.h | 1 |
4 files changed, 13 insertions, 2 deletions
diff --git a/src/qml/compiler/qv4codegen.cpp b/src/qml/compiler/qv4codegen.cpp index bc4ca5d6f4..a262908960 100644 --- a/src/qml/compiler/qv4codegen.cpp +++ b/src/qml/compiler/qv4codegen.cpp @@ -2075,6 +2075,14 @@ int Codegen::defineFunction(const QString &name, AST::Node *ast, _context->hasDirectEval |= (_context->compilationMode == EvalCode || _context->compilationMode == GlobalCode || _module->debugMode); // Conditional breakpoints are like eval in the function + // When a user writes the following QML signal binding: + // onSignal: function() { doSomethingUsefull } + // we will generate a binding function that just returns the closure. However, that's not useful + // at all, because if the onSignal is a signal handler, the user is actually making it explicit + // that the binding is a function, so we should execute that. However, we don't know that during + // AOT compilation, so mark the surrounding function as only-returning-a-closure. + _context->returnsClosure = cast<ExpressionStatement *>(ast) && cast<FunctionExpression *>(cast<ExpressionStatement *>(ast)->expression); + BytecodeGenerator bytecode(_context->line, _module->debugMode); BytecodeGenerator *savedBytecodeGenerator; savedBytecodeGenerator = bytecodeGenerator; diff --git a/src/qml/compiler/qv4compileddata_p.h b/src/qml/compiler/qv4compileddata_p.h index f1776f5772..e6c4225bbd 100644 --- a/src/qml/compiler/qv4compileddata_p.h +++ b/src/qml/compiler/qv4compileddata_p.h @@ -225,7 +225,7 @@ struct Function quint32_le localsOffset; quint32_le nLineNumbers; quint32_le lineNumberOffset; - quint32_le nInnerFunctions; + quint32_le nestedFunctionIndex; // for functions that only return a single closure, used in signal handlers quint32_le nRegisters; Location location; diff --git a/src/qml/compiler/qv4compiler.cpp b/src/qml/compiler/qv4compiler.cpp index f2e1f4a0de..ccc909c199 100644 --- a/src/qml/compiler/qv4compiler.cpp +++ b/src/qml/compiler/qv4compiler.cpp @@ -305,6 +305,9 @@ void QV4::Compiler::JSUnitGenerator::writeFunction(char *f, QV4::Compiler::Conte function->flags |= CompiledData::Function::IsStrict; if (irFunction->hasTry || irFunction->hasWith) function->flags |= CompiledData::Function::HasCatchOrWith; + function->nestedFunctionIndex = + irFunction->returnsClosure ? quint32(module->functions.indexOf(irFunction->nestedContexts.first())) + : std::numeric_limits<uint32_t>::max(); function->nFormals = irFunction->arguments.size(); function->formalsOffset = currentOffset; currentOffset += function->nFormals * sizeof(quint32); @@ -317,7 +320,6 @@ void QV4::Compiler::JSUnitGenerator::writeFunction(char *f, QV4::Compiler::Conte function->lineNumberOffset = currentOffset; currentOffset += function->nLineNumbers * sizeof(CompiledData::CodeOffsetToLine); - function->nInnerFunctions = irFunction->nestedContexts.size(); function->nRegisters = irFunction->registerCount; diff --git a/src/qml/compiler/qv4compilercontext_p.h b/src/qml/compiler/qv4compilercontext_p.h index a78a66db52..8fabf41c40 100644 --- a/src/qml/compiler/qv4compilercontext_p.h +++ b/src/qml/compiler/qv4compilercontext_p.h @@ -144,6 +144,7 @@ struct Context { bool usesThis = false; bool hasTry = false; bool hasWith = false; + bool returnsClosure = false; mutable bool argumentsCanEscape = false; enum UsesArgumentsObject { |