Add support for function calls with spread

Function calls with thread are modelled by pushing
an empty value in front of every argument that
requires spreading. The runtime methods callWithSpread
and constructWithSpread then take care of spreading
out the arguments.

Change-Id: Ie877c59d3d9d08fc5f20d7befb7153c7b716bf30
Reviewed-by: Simon Hausmann <simon.hausmann@qt.io>

5 files changed, 105 insertions, 23 deletions

diff --git a/src/qml/compiler/qv4bytecodehandler.cpp b/src/qml/compiler/qv4bytecodehandler.cpp
index 3e4844a1ac..8d1ac0bfd9 100644
--- a/src/qml/compiler/qv4bytecodehandler.cpp
+++ b/src/qml/compiler/qv4bytecodehandler.cpp
@@ -263,6 +263,15 @@ std::vector<int> ByteCodeHandler::collectLabelsInBytecode(const char *code, uint
         COLLECTOR_BEGIN_INSTR(CallContextObjectProperty)
         COLLECTOR_END_INSTR(CallContextObjectProperty)
 
+        COLLECTOR_BEGIN_INSTR(CallWithSpread)
+        COLLECTOR_END_INSTR(CallWithSpread)
+
+        COLLECTOR_BEGIN_INSTR(Construct)
+        COLLECTOR_END_INSTR(Construct)
+
+        COLLECTOR_BEGIN_INSTR(ConstructWithSpread)
+        COLLECTOR_END_INSTR(ConstructWithSpread)
+
         COLLECTOR_BEGIN_INSTR(SetUnwindHandler)
             addLabel(code - start + offset);
         COLLECTOR_END_INSTR(SetUnwindHandler)
@@ -355,9 +364,6 @@ std::vector<int> ByteCodeHandler::collectLabelsInBytecode(const char *code, uint
         COLLECTOR_BEGIN_INSTR(ToObject)
         COLLECTOR_END_INSTR(ToObject)
 
-        COLLECTOR_BEGIN_INSTR(Construct)
-        COLLECTOR_END_INSTR(Construct)
-
         COLLECTOR_BEGIN_INSTR(Jump)
             addLabel(code - start + offset);
         COLLECTOR_END_INSTR(Jump)
diff --git a/src/qml/compiler/qv4codegen.cpp b/src/qml/compiler/qv4codegen.cpp
index 6682f604de..fc2fb86666 100644
--- a/src/qml/compiler/qv4codegen.cpp
+++ b/src/qml/compiler/qv4codegen.cpp
@@ -1610,6 +1610,7 @@ bool Codegen::visit(CallExpression *ast)
     RegisterScope scope(this);
 
     Reference base = expression(ast->base);
+
     if (hasError)
         return false;
     switch (base.type) {
@@ -1626,10 +1627,36 @@ bool Codegen::visit(CallExpression *ast)
         break;
     }
 
+    int thisObject = bytecodeGenerator->newRegister();
+    int functionObject = bytecodeGenerator->newRegister();
+
     auto calldata = pushArgs(ast->arguments);
     if (hasError)
         return false;
 
+    if (calldata.hasSpread) {
+        Reference baseObject = base.baseObject();
+        if (!baseObject.isStackSlot()) {
+            baseObject.storeOnStack(thisObject);
+            baseObject = Reference::fromStackSlot(this, thisObject);
+        }
+        if (!base.isStackSlot()) {
+            base.storeOnStack(functionObject);
+            base = Reference::fromStackSlot(this, functionObject);
+        }
+
+        Instruction::CallWithSpread call;
+        call.func = base.stackSlot();
+        call.thisObject = baseObject.stackSlot();
+        call.argc = calldata.argc;
+        call.argv = calldata.argv;
+        bytecodeGenerator->addInstruction(call);
+
+        _expr.setResult(Reference::fromAccumulator(this));
+        return false;
+
+    }
+
     handleCall(base, calldata);
     return false;
 }
@@ -1707,36 +1734,41 @@ void Codegen::handleCall(Reference &base, Arguments calldata)
 
 Codegen::Arguments Codegen::pushArgs(ArgumentList *args)
 {
+    bool hasSpread = false;
     int argc = 0;
     for (ArgumentList *it = args; it; it = it->next) {
         if (it->isSpreadElement) {
-            throwSyntaxError(it->firstSourceLocation(), QLatin1String("'...' in argument lists is unimplemented."));
-            return { 0, 0 };
+            hasSpread = true;
+            ++argc;
         }
         ++argc;
     }
 
     if (!argc)
-        return { 0, 0 };
+        return { 0, 0, false };
 
     int calldata = bytecodeGenerator->newRegisterArray(argc);
 
     argc = 0;
     for (ArgumentList *it = args; it; it = it->next) {
+        if (it->isSpreadElement) {
+            Reference::fromConst(this, Primitive::emptyValue().asReturnedValue()).storeOnStack(calldata + argc);
+            ++argc;
+        }
         RegisterScope scope(this);
         Reference e = expression(it->expression);
         if (hasError)
             break;
-        if (!argc && !it->next) {
+        if (!argc && !it->next && !hasSpread) {
             // avoid copy for functions taking a single argument
             if (e.isStackSlot())
-                return { 1, e.stackSlot() };
+                return { 1, e.stackSlot(), hasSpread };
         }
         (void) e.storeOnStack(calldata + argc);
         ++argc;
     }
 
-    return { argc, calldata };
+    return { argc, calldata, hasSpread };
 }
 
 Codegen::Arguments Codegen::pushTemplateArgs(TemplateLiteral *args)
@@ -1746,7 +1778,7 @@ Codegen::Arguments Codegen::pushTemplateArgs(TemplateLiteral *args)
         ++argc;
 
     if (!argc)
-        return { 0, 0 };
+        return { 0, 0, false };
 
     int calldata = bytecodeGenerator->newRegisterArray(argc);
 
@@ -1760,7 +1792,7 @@ Codegen::Arguments Codegen::pushTemplateArgs(TemplateLiteral *args)
         ++argc;
     }
 
-    return { argc, calldata };
+    return { argc, calldata, false };
 }
 
 bool Codegen::visit(ConditionalExpression *ast)
@@ -2096,11 +2128,19 @@ bool Codegen::visit(NewMemberExpression *ast)
     if (hasError)
         return false;
 
-    Instruction::Construct create;
-    create.func = base.stackSlot();
-    create.argc = calldata.argc;
-    create.argv = calldata.argv;
-    bytecodeGenerator->addInstruction(create);
+    if (calldata.hasSpread) {
+        Instruction::ConstructWithSpread create;
+        create.func = base.stackSlot();
+        create.argc = calldata.argc;
+        create.argv = calldata.argv;
+        bytecodeGenerator->addInstruction(create);
+    } else {
+        Instruction::Construct create;
+        create.func = base.stackSlot();
+        create.argc = calldata.argc;
+        create.argv = calldata.argv;
+        bytecodeGenerator->addInstruction(create);
+    }
     _expr.setResult(Reference::fromAccumulator(this));
     return false;
 }
@@ -3640,6 +3680,28 @@ Codegen::Reference Codegen::Reference::storeConsumeAccumulator() const
     return Reference();
 }
 
+Codegen::Reference Codegen::Reference::baseObject() const
+{
+    if (type == Reference::QmlScopeObject || type == Reference::QmlContextObject) {
+        return Reference::fromStackSlot(codegen, qmlBase.stackSlot());
+    } else if (type == Reference::Member) {
+        RValue rval = propertyBase;
+        if (!rval.isValid())
+            return Reference::fromConst(codegen, Encode::undefined());
+        if (rval.isAccumulator())
+            return Reference::fromAccumulator(codegen);
+        if (rval.isStackSlot())
+            Reference::fromStackSlot(codegen, rval.stackSlot());
+        if (rval.isConst())
+            return Reference::fromConst(codegen, rval.constantValue());
+        Q_UNREACHABLE();
+    } else if (type == Reference::Subscript) {
+        return Reference::fromStackSlot(codegen, elementBase.stackSlot());
+    } else {
+        return Reference::fromConst(codegen, Encode::undefined());
+    }
+}
+
 Codegen::Reference Codegen::Reference::storeOnStack() const
 { return doStoreOnStack(-1); }
 
diff --git a/src/qml/compiler/qv4codegen_p.h b/src/qml/compiler/qv4codegen_p.h
index 3750811eaf..83b8731179 100644
--- a/src/qml/compiler/qv4codegen_p.h
+++ b/src/qml/compiler/qv4codegen_p.h
@@ -325,6 +325,8 @@ public:
         Q_REQUIRED_RESULT Reference storeRetainAccumulator() const;
         Reference storeConsumeAccumulator() const;
 
+        Q_REQUIRED_RESULT Reference baseObject() const;
+
         bool storeWipesAccumulator() const;
         void loadInAccumulator() const;
 
@@ -637,7 +639,7 @@ public:
 
     Reference binopHelper(QSOperator::Op oper, Reference &left, Reference &right);
     Reference jumpBinop(QSOperator::Op oper, Reference &left, Reference &right);
-    struct Arguments { int argc; int argv; };
+    struct Arguments { int argc; int argv; bool hasSpread; };
     Arguments pushArgs(AST::ArgumentList *args);
     void handleCall(Reference &base, Arguments calldata);
 
diff --git a/src/qml/compiler/qv4instr_moth.cpp b/src/qml/compiler/qv4instr_moth.cpp
index 6f603f9488..df5dd5610c 100644
--- a/src/qml/compiler/qv4instr_moth.cpp
+++ b/src/qml/compiler/qv4instr_moth.cpp
@@ -376,6 +376,18 @@ void dumpBytecode(const char *code, int len, int nLocals, int nFormals, int /*st
             d << dumpRegister(base, nFormals) << "." << name << dumpArguments(argc, argv, nFormals);
         MOTH_END_INSTR(CallContextObjectProperty)
 
+        MOTH_BEGIN_INSTR(CallWithSpread)
+            d << "new" << dumpRegister(func, nFormals) << dumpRegister(thisObject, nFormals) << dumpArguments(argc, argv, nFormals);
+        MOTH_END_INSTR(CallWithSpread)
+
+        MOTH_BEGIN_INSTR(Construct)
+            d << "new" << dumpRegister(func, nFormals) << dumpArguments(argc, argv, nFormals);
+        MOTH_END_INSTR(Construct)
+
+        MOTH_BEGIN_INSTR(ConstructWithSpread)
+            d << "new" << dumpRegister(func, nFormals) << dumpArguments(argc, argv, nFormals);
+        MOTH_END_INSTR(ConstructWithSpread)
+
         MOTH_BEGIN_INSTR(SetUnwindHandler)
             if (offset)
                 d << ABSOLUTE_OFFSET();
@@ -486,10 +498,6 @@ void dumpBytecode(const char *code, int len, int nLocals, int nFormals, int /*st
         MOTH_BEGIN_INSTR(ToObject)
         MOTH_END_INSTR(ToObject)
 
-        MOTH_BEGIN_INSTR(Construct)
-            d << "new" << dumpRegister(func, nFormals) << dumpArguments(argc, argv, nFormals);
-        MOTH_END_INSTR(Construct)
-
         MOTH_BEGIN_INSTR(Jump)
             d << ABSOLUTE_OFFSET();
         MOTH_END_INSTR(Jump)
diff --git a/src/qml/compiler/qv4instr_moth_p.h b/src/qml/compiler/qv4instr_moth_p.h
index d4d630dfaf..85b30507a1 100644
--- a/src/qml/compiler/qv4instr_moth_p.h
+++ b/src/qml/compiler/qv4instr_moth_p.h
@@ -109,6 +109,9 @@ QT_BEGIN_NAMESPACE
 #define INSTR_CallGlobalLookup(op) INSTRUCTION(op, CallGlobalLookup, 3, index, argc, argv)
 #define INSTR_CallScopeObjectProperty(op) INSTRUCTION(op, CallScopeObjectProperty, 4, name, base, argc, argv)
 #define INSTR_CallContextObjectProperty(op) INSTRUCTION(op, CallContextObjectProperty, 4, name, base, argc, argv)
+#define INSTR_CallWithSpread(op) INSTRUCTION(op, CallWithSpread, 4, func, thisObject, argc, argv)
+#define INSTR_Construct(op) INSTRUCTION(op, Construct, 3, func, argc, argv)
+#define INSTR_ConstructWithSpread(op) INSTRUCTION(op, ConstructWithSpread, 3, func, argc, argv)
 #define INSTR_SetUnwindHandler(op) INSTRUCTION(op, SetUnwindHandler, 1, offset)
 #define INSTR_UnwindDispatch(op) INSTRUCTION(op, UnwindDispatch, 0)
 #define INSTR_UnwindToLabel(op) INSTRUCTION(op, UnwindToLabel, 2, level, offset)
@@ -139,7 +142,6 @@ QT_BEGIN_NAMESPACE
 #define INSTR_CreateRestParameter(op) INSTRUCTION(op, CreateRestParameter, 1, argIndex)
 #define INSTR_ConvertThisToObject(op) INSTRUCTION(op, ConvertThisToObject, 0)
 #define INSTR_ToObject(op) INSTRUCTION(op, ToObject, 0)
-#define INSTR_Construct(op) INSTRUCTION(op, Construct, 3, func, argc, argv)
 #define INSTR_Jump(op) INSTRUCTION(op, Jump, 1, offset)
 #define INSTR_JumpTrue(op) INSTRUCTION(op, JumpTrue, 1, offset)
 #define INSTR_JumpFalse(op) INSTRUCTION(op, JumpFalse, 1, offset)
@@ -235,6 +237,9 @@ QT_BEGIN_NAMESPACE
     F(CallGlobalLookup) \
     F(CallScopeObjectProperty) \
     F(CallContextObjectProperty) \
+    F(CallWithSpread) \
+    F(Construct) \
+    F(ConstructWithSpread) \
     F(SetUnwindHandler) \
     F(UnwindDispatch) \
     F(UnwindToLabel) \
@@ -265,7 +270,6 @@ QT_BEGIN_NAMESPACE
     F(CreateRestParameter) \
     F(ConvertThisToObject) \
     F(ToObject) \
-    F(Construct) \
     F(Jump) \
     F(JumpTrue) \
     F(JumpFalse) \