Add Throw instruction to the V4 virtual machine

Also, throw an exception when trying to assign something that is not
a QUrl or a QString to a QUrl.

Change-Id: Ic48fd519c8318d391706ebca1955a5dd2ef6e80e
Reviewed-by: Aaron Kennedy <aaron.kennedy@nokia.com>

7 files changed, 49 insertions, 2 deletions

diff --git a/src/qml/qml/v4/qv4bindings.cpp b/src/qml/qml/v4/qv4bindings.cpp
index 97d37400ac..3158f8fc2a 100644
--- a/src/qml/qml/v4/qv4bindings.cpp
+++ b/src/qml/qml/v4/qv4bindings.cpp
@@ -592,6 +592,11 @@ inline quint32 QV4Bindings::toUint32(double n)
     goto exceptionExit; \
 } 
 
+#define THROW_VALUE_EXCEPTION_STR(id, str) { \
+    throwException((id), error, program, context, (str)); \
+    goto exceptionExit; \
+}
+
 #define THROW_EXCEPTION(id) THROW_EXCEPTION_STR(id, QString())
 
 #define MARK_REGISTER(reg) cleanupRegisterMask |= (1 << (reg))
@@ -1672,6 +1677,10 @@ void QV4Bindings::run(int instrIndex, quint32 &executedBlocks,
         registers[instr->cleanup.reg].cleanup();
     QML_V4_END_INSTR(CleanupRegister, cleanup)
 
+    QML_V4_BEGIN_INSTR(Throw, throwop)
+        THROW_VALUE_EXCEPTION_STR(instr->throwop.exceptionId, *registers[instr->throwop.message].getstringptr());
+    QML_V4_END_INSTR(Throw, throwop)
+
 #ifdef QML_THREADED_INTERPRETER
     // nothing to do
 #else
diff --git a/src/qml/qml/v4/qv4compiler.cpp b/src/qml/qml/v4/qv4compiler.cpp
index 08cfed9383..e833aed3fd 100644
--- a/src/qml/qml/v4/qv4compiler.cpp
+++ b/src/qml/qml/v4/qv4compiler.cpp
@@ -63,6 +63,7 @@ static bool qmlEnableV4 = true;
 using namespace QQmlJS;
 QV4CompilerPrivate::QV4CompilerPrivate()
     : _function(0) , _block(0) , _discarded(false), registerCount(0)
+    , bindingLine(0), bindingColumn(0)
 {
 }
 
@@ -73,6 +74,8 @@ void QV4CompilerPrivate::trace(int line, int column)
 {
     bytecode.clear();
 
+    this->bindingLine = line;
+    this->bindingColumn = column;
     this->currentReg = _function->tempCount;
     this->registerCount = qMax(this->registerCount, this->currentReg);
 
@@ -317,7 +320,7 @@ void QV4CompilerPrivate::visitName(IR::Name *e)
         Instr::LoadAttached attached;
         attached.output = currentReg;
         attached.reg = currentReg;
-        attached.exceptionId = exceptionId(e->line, e->column);
+        attached.exceptionId = exceptionId(bindingLine, bindingColumn);
         if (e->declarativeType->attachedPropertiesId() == -1)
             discard();
         attached.id = e->declarativeType->attachedPropertiesId();
@@ -966,6 +969,16 @@ void QV4CompilerPrivate::visitMove(IR::Move *s)
                 // url-to-xxx conversions.
                 break;
             default: {
+                if (s->isMoveForReturn) {
+                    V4Instr instr;
+                    instr.throwop.exceptionId = exceptionId(bindingLine, bindingColumn);
+                    registerLiteralString(dest, _function->newString(QString::fromUtf8("Unable to assign %1 to %2")
+                                                                     .arg(QLatin1String(IR::typeName(sourceTy)))
+                                                                     .arg(QLatin1String(IR::typeName(targetTy)))));
+                    instr.throwop.message = dest;
+                    gen(V4Instr::Throw, instr);
+                    return;
+                }
                 // generate a UrlToString conversion and fix
                 // the type of the source expression.
                 V4Instr conv;
@@ -1018,6 +1031,17 @@ void QV4CompilerPrivate::visitMove(IR::Move *s)
             default: break;
             } // switch
         } else if (targetTy == IR::UrlType) {
+            if (s->isMoveForReturn && sourceTy != IR::StringType) {
+                V4Instr instr;
+                instr.throwop.exceptionId = exceptionId(bindingLine, bindingColumn);
+                registerLiteralString(dest, _function->newString(QString::fromUtf8("Unable to assign %1 to %2")
+                                                                 .arg(QLatin1String(IR::typeName(sourceTy)))
+                                                                 .arg(QLatin1String(IR::typeName(targetTy)))));
+                instr.throwop.message = dest;
+                gen(V4Instr::Throw, instr);
+                return;
+            }
+
             V4Instr convToString;
             convToString.unaryop.output = dest;
             convToString.unaryop.src = src;
diff --git a/src/qml/qml/v4/qv4compiler_p_p.h b/src/qml/qml/v4/qv4compiler_p_p.h
index 984f20b1b8..782ca594ae 100644
--- a/src/qml/qml/v4/qv4compiler_p_p.h
+++ b/src/qml/qml/v4/qv4compiler_p_p.h
@@ -235,6 +235,8 @@ private:
 
     bool usedSubscriptionIdsChanged;
     quint32 currentBlockMask;
+    int bindingLine;
+    int bindingColumn;
 };
 
 
diff --git a/src/qml/qml/v4/qv4instruction.cpp b/src/qml/qml/v4/qv4instruction.cpp
index 26029046f6..4298be28ae 100644
--- a/src/qml/qml/v4/qv4instruction.cpp
+++ b/src/qml/qml/v4/qv4instruction.cpp
@@ -382,6 +382,9 @@ void Bytecode::dump(const V4Instr *i, int address) const
     case V4Instr::Block:
         INSTR_DUMP << "\t" << "Block" << "\t\t\t" << "Mask(" << QByteArray::number(i->blockop.block, 16).constData()  << ")";
         break;
+    case V4Instr::Throw:
+        INSTR_DUMP << "\t" << "Throw" << "\t\t\t" << "InputReg(" << i->throwop.message  << ")";
+        break;
     default:
         INSTR_DUMP << "\t" << "Unknown";
         break;
diff --git a/src/qml/qml/v4/qv4instruction_p.h b/src/qml/qml/v4/qv4instruction_p.h
index 49ac65ccf0..46a03b37c7 100644
--- a/src/qml/qml/v4/qv4instruction_p.h
+++ b/src/qml/qml/v4/qv4instruction_p.h
@@ -160,6 +160,7 @@ QT_BEGIN_NAMESPACE
     F(BranchFalse, branchop) \
     F(Branch, branchop) \
     F(Block, blockop) \
+    F(Throw, throwop) \
     /* Speculative property resolution */ \
     F(InitString, initstring)
 
@@ -359,6 +360,12 @@ union Q_AUTOTEST_EXPORT V4Instr {
         quint32 block;
     };
 
+    struct instr_throwop {
+        QML_V4_INSTR_HEADER
+        quint8 exceptionId;
+        quint32 message;
+    };
+
     instr_common common;
     instr_id id;
     instr_init init;
@@ -384,6 +391,7 @@ union Q_AUTOTEST_EXPORT V4Instr {
     instr_initstring initstring;
     instr_branchop branchop;
     instr_blockop blockop;
+    instr_throwop throwop;
 };
 
 template<int N>
diff --git a/src/qml/qml/v4/qv4ir.cpp b/src/qml/qml/v4/qv4ir.cpp
index 8fc4719791..2bd0720260 100644
--- a/src/qml/qml/v4/qv4ir.cpp
+++ b/src/qml/qml/v4/qv4ir.cpp
@@ -50,7 +50,7 @@ QT_BEGIN_NAMESPACE
 namespace QQmlJS {
 namespace IR {
 
-inline const char *typeName(Type t)
+const char *typeName(Type t)
 {
     switch (t) {
     case InvalidType: return "invalid";
diff --git a/src/qml/qml/v4/qv4ir_p.h b/src/qml/qml/v4/qv4ir_p.h
index d670876786..26bd43c406 100644
--- a/src/qml/qml/v4/qv4ir_p.h
+++ b/src/qml/qml/v4/qv4ir_p.h
@@ -155,6 +155,7 @@ enum Type {
 };
 Type maxType(IR::Type left, IR::Type right);
 bool isRealType(IR::Type type);
+const char *typeName(IR::Type t);
 
 struct ExprVisitor {
     virtual ~ExprVisitor() {}