Rework IR code generation for try/catch/finally

Simplify the generated code. Add a special block to catch
exceptions thrown inside a catch() statement.

store the exception on the stack when entering finally and
rethrow it at the end. This ensure correct behavior for
break/continue/return statements inside finally.

Don't check for exceptions after calling push_catch_scope
and pop_scope in the JIT'ed code. This can lead to infinite
loops when throwing inside an exception handler.

Change-Id: I67e9325794e2fd25b0773b21e02fbaadb43faab0

Change-Id: Ic1ea9c0c43eec1d49177dc1ab4552a1da04e96fe
Reviewed-by: Simon Hausmann <[email protected]>

1 files changed, 10 insertions, 1 deletions

diff --git a/src/qml/compiler/qv4isel_masm_p.h b/src/qml/compiler/qv4isel_masm_p.h
index 3d1b271cdc..40d1aa5275 100644
--- a/src/qml/compiler/qv4isel_masm_p.h
+++ b/src/qml/compiler/qv4isel_masm_p.h
@@ -95,7 +95,15 @@ template <typename T>
 struct ExceptionCheck {
     enum { NeedsCheck = 1 };
 };
-
+// push_catch and pop context methods shouldn't check for exceptions
+template <>
+struct ExceptionCheck<QV4::ExecutionContext *(*)(QV4::ExecutionContext *)> {
+    enum { NeedsCheck = 0 };
+};
+template <typename A>
+struct ExceptionCheck<QV4::ExecutionContext *(*)(QV4::ExecutionContext *, A)> {
+    enum { NeedsCheck = 0 };
+};
 
 class Assembler : public JSC::MacroAssembler
 {
@@ -1444,6 +1452,7 @@ protected:
     virtual void callBuiltinDeleteValue(V4IR::Temp *result);
     virtual void callBuiltinThrow(V4IR::Expr *arg);
     virtual void callBuiltinReThrow();
+    virtual void callBuiltinUnwindException(V4IR::Temp *);
     virtual void callBuiltinPushCatchScope(const QString &exceptionName);
     virtual void callBuiltinForeachIteratorObject(V4IR::Temp *arg, V4IR::Temp *result);
     virtual void callBuiltinForeachNextPropertyname(V4IR::Temp *arg, V4IR::Temp *result);