use lookups for the global scope

Gives about 12% speed improvement for the V8 benchmark.
fact.2.js is almost twice as fast.

Change-Id: Icfa1a780b30e131b9531e12f4bd569516c404e86
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>

13 files changed, 180 insertions, 12 deletions

diff --git a/src/v4/moth/qv4isel_moth.cpp b/src/v4/moth/qv4isel_moth.cpp
index 31bf1fb36d..00ae4e1029 100644
--- a/src/v4/moth/qv4isel_moth.cpp
+++ b/src/v4/moth/qv4isel_moth.cpp
@@ -245,10 +245,10 @@ void InstructionSelection::loadRegexp(V4IR::RegExp *sourceRegexp, V4IR::Temp *ta
     addInstruction(load);
 }
 
-void InstructionSelection::getActivationProperty(const QString &name, V4IR::Temp *temp)
+void InstructionSelection::getActivationProperty(const V4IR::Name *name, V4IR::Temp *temp)
 {
     Instruction::LoadName load;
-    load.name = identifier(name);
+    load.name = identifier(*name->id);
     load.result = getResultParam(temp);
     addInstruction(load);
 }
diff --git a/src/v4/moth/qv4isel_moth_p.h b/src/v4/moth/qv4isel_moth_p.h
index 090d151df5..5e057139e2 100644
--- a/src/v4/moth/qv4isel_moth_p.h
+++ b/src/v4/moth/qv4isel_moth_p.h
@@ -63,7 +63,7 @@ protected:
     virtual void loadConst(V4IR::Const *sourceConst, V4IR::Temp *targetTemp);
     virtual void loadString(const QString &str, V4IR::Temp *targetTemp);
     virtual void loadRegexp(V4IR::RegExp *sourceRegexp, V4IR::Temp *targetTemp);
-    virtual void getActivationProperty(const QString &name, V4IR::Temp *temp);
+    virtual void getActivationProperty(const V4IR::Name *name, V4IR::Temp *temp);
     virtual void setActivationProperty(V4IR::Temp *source, const QString &targetName);
     virtual void initClosure(V4IR::Closure *closure, V4IR::Temp *target);
     virtual void getProperty(V4IR::Temp *base, const QString &name, V4IR::Temp *target);
diff --git a/src/v4/qv4codegen.cpp b/src/v4/qv4codegen.cpp
index df931fd767..c91458282f 100644
--- a/src/v4/qv4codegen.cpp
+++ b/src/v4/qv4codegen.cpp
@@ -1959,7 +1959,7 @@ V4IR::Expr *Codegen::identifier(const QString &name, int line, int col)
     V4IR::Function *f = _function;
 
     while (f && e->parent) {
-        if ((f->usesArgumentsObject && name == "arguments") || (!f->isStrict && f->hasDirectEval) || f->insideWithOrCatch)
+        if ((f->usesArgumentsObject && name == "arguments") || (!f->isStrict && f->hasDirectEval) || f->insideWithOrCatch || (f->isNamedExpression && f->name == name))
             break;
         int index = e->findMember(name);
         assert (index < e->members.size());
@@ -1974,6 +1974,9 @@ V4IR::Expr *Codegen::identifier(const QString &name, int line, int col)
         f = f->outer;
     }
 
+    if (!e->parent && (!f || !f->insideWithOrCatch) && _mode != EvalCode && (!f || f->name != name))
+        return _block->GLOBALNAME(name, line, col);
+
     // global context or with. Lookup by name
     return _block->NAME(name, line, col);
 
diff --git a/src/v4/qv4isel_masm.cpp b/src/v4/qv4isel_masm.cpp
index 9d8795f198..80803e811c 100644
--- a/src/v4/qv4isel_masm.cpp
+++ b/src/v4/qv4isel_masm.cpp
@@ -599,7 +599,23 @@ void InstructionSelection::run(VM::Function *vmFunction, V4IR::Function *functio
 
 void InstructionSelection::callBuiltinInvalid(V4IR::Name *func, V4IR::ExprList *args, V4IR::Temp *result)
 {
-    callRuntimeMethod(result, __qmljs_call_activation_property, func, args);
+    int argc = prepareVariableArguments(args);
+    VM::String *s = identifier(*func->id);
+
+    if (useFastLookups && func->global) {
+        uint index = addGlobalLookup(s);
+        generateFunctionCall(Assembler::Void, __qmljs_call_global_lookup,
+                             Assembler::ContextRegister, Assembler::PointerToValue(result),
+                             Assembler::TrustedImm32(index),
+                             baseAddressForCallArguments(),
+                             Assembler::TrustedImm32(argc));
+    } else {
+        generateFunctionCall(Assembler::Void, __qmljs_call_activation_property,
+                             Assembler::ContextRegister, Assembler::PointerToValue(result),
+                             s,
+                             baseAddressForCallArguments(),
+                             Assembler::TrustedImm32(argc));
+    }
 }
 
 void InstructionSelection::callBuiltinTypeofMember(V4IR::Temp *base, const QString &name, V4IR::Temp *result)
@@ -830,9 +846,15 @@ void InstructionSelection::loadRegexp(V4IR::RegExp *sourceRegexp, V4IR::Temp *ta
     _as->storeValue(v, targetTemp);
 }
 
-void InstructionSelection::getActivationProperty(const QString &name, V4IR::Temp *temp)
+void InstructionSelection::getActivationProperty(const V4IR::Name *name, V4IR::Temp *temp)
 {
-    String *propertyName = identifier(name);
+    String *propertyName = identifier(*name->id);
+    if (useFastLookups && name->global) {
+        uint index = addGlobalLookup(propertyName);
+        generateFunctionCall(Assembler::Void, __qmljs_get_global_lookup, Assembler::ContextRegister, Assembler::PointerToValue(temp),
+                             Assembler::TrustedImm32(index));
+        return;
+    }
     generateFunctionCall(Assembler::Void, __qmljs_get_activation_property, Assembler::ContextRegister, Assembler::PointerToValue(temp), propertyName);
 }
 
@@ -1196,3 +1218,17 @@ uint InstructionSelection::addLookup(VM::String *name)
     _lookups.append(l);
     return index;
 }
+
+uint InstructionSelection::addGlobalLookup(VM::String *name)
+{
+    uint index = (uint)_lookups.size();
+    VM::Lookup l;
+    l.lookupGlobal = Lookup::lookupGlobalGeneric;
+    for (int i = 0; i < Lookup::Size; ++i)
+        l.classList[i] = 0;
+    l.level = -1;
+    l.index = UINT_MAX;
+    l.name = name;
+    _lookups.append(l);
+    return index;
+}
diff --git a/src/v4/qv4isel_masm_p.h b/src/v4/qv4isel_masm_p.h
index ab05b82992..9f8704725f 100644
--- a/src/v4/qv4isel_masm_p.h
+++ b/src/v4/qv4isel_masm_p.h
@@ -805,7 +805,7 @@ protected:
     virtual void loadConst(V4IR::Const *sourceConst, V4IR::Temp *targetTemp);
     virtual void loadString(const QString &str, V4IR::Temp *targetTemp);
     virtual void loadRegexp(V4IR::RegExp *sourceRegexp, V4IR::Temp *targetTemp);
-    virtual void getActivationProperty(const QString &name, V4IR::Temp *temp);
+    virtual void getActivationProperty(const V4IR::Name *name, V4IR::Temp *temp);
     virtual void setActivationProperty(V4IR::Temp *source, const QString &targetName);
     virtual void initClosure(V4IR::Closure *closure, V4IR::Temp *target);
     virtual void getProperty(V4IR::Temp *base, const QString &name, V4IR::Temp *target);
@@ -870,6 +870,7 @@ private:
     callRuntimeMethodImp(result, isel_stringIfy(function), function, __VA_ARGS__)
 
     uint addLookup(VM::String *name);
+    uint addGlobalLookup(VM::String *name);
 
     V4IR::BasicBlock *_block;
     V4IR::Function* _function;
diff --git a/src/v4/qv4isel_p.cpp b/src/v4/qv4isel_p.cpp
index d355e16104..417e38550e 100644
--- a/src/v4/qv4isel_p.cpp
+++ b/src/v4/qv4isel_p.cpp
@@ -86,7 +86,7 @@ void InstructionSelection::visitMove(V4IR::Move *s)
                 if (*n->id == QStringLiteral("this")) // TODO: `this' should be a builtin.
                     loadThisObject(t);
                 else
-                    getActivationProperty(*n->id, t);
+                    getActivationProperty(n, t);
                 return;
             } else if (V4IR::Const *c = s->source->asConst()) {
                 loadConst(c, t);
diff --git a/src/v4/qv4isel_p.h b/src/v4/qv4isel_p.h
index 4d02b5fff4..e85127c5a9 100644
--- a/src/v4/qv4isel_p.h
+++ b/src/v4/qv4isel_p.h
@@ -134,7 +134,7 @@ public: // to implement by subclasses:
     virtual void loadConst(V4IR::Const *sourceConst, V4IR::Temp *targetTemp) = 0;
     virtual void loadString(const QString &str, V4IR::Temp *targetTemp) = 0;
     virtual void loadRegexp(V4IR::RegExp *sourceRegexp, V4IR::Temp *targetTemp) = 0;
-    virtual void getActivationProperty(const QString &name, V4IR::Temp *temp) = 0;
+    virtual void getActivationProperty(const V4IR::Name *name, V4IR::Temp *temp) = 0;
     virtual void setActivationProperty(V4IR::Temp *source, const QString &targetName) = 0;
     virtual void initClosure(V4IR::Closure *closure, V4IR::Temp *target) = 0;
     virtual void getProperty(V4IR::Temp *base, const QString &name, V4IR::Temp *target) = 0;
diff --git a/src/v4/qv4jsir.cpp b/src/v4/qv4jsir.cpp
index ddf6509f27..3dad094624 100644
--- a/src/v4/qv4jsir.cpp
+++ b/src/v4/qv4jsir.cpp
@@ -328,10 +328,20 @@ void RegExp::dump(QTextStream &out)
     out << '/' << *value << '/' << f;
 }
 
+void Name::initGlobal(const QString *id, quint32 line, quint32 column)
+{
+    this->id = id;
+    this->builtin = builtin_invalid;
+    this->global = true;
+    this->line = line;
+    this->column = column;
+}
+
 void Name::init(const QString *id, quint32 line, quint32 column)
 {
     this->id = id;
     this->builtin = builtin_invalid;
+    this->global = false;
     this->line = line;
     this->column = column;
 }
@@ -340,6 +350,7 @@ void Name::init(Builtin builtin, quint32 line, quint32 column)
 {
     this->id = 0;
     this->builtin = builtin;
+    this->global = false;
     this->line = line;
     this->column = column;
 }
@@ -644,6 +655,14 @@ Name *BasicBlock::NAME(const QString &id, quint32 line, quint32 column)
     return e;
 }
 
+Name *BasicBlock::GLOBALNAME(const QString &id, quint32 line, quint32 column)
+{
+    Name *e = function->New<Name>();
+    e->initGlobal(function->newString(id), line, column);
+    return e;
+}
+
+
 Name *BasicBlock::NAME(Name::Builtin builtin, quint32 line, quint32 column)
 {
     Name *e = function->New<Name>();
diff --git a/src/v4/qv4jsir_p.h b/src/v4/qv4jsir_p.h
index b8377b941d..47368449fc 100644
--- a/src/v4/qv4jsir_p.h
+++ b/src/v4/qv4jsir_p.h
@@ -304,9 +304,11 @@ struct Name: Expr {
 
     const QString *id;
     Builtin builtin;
+    bool global;
     quint32 line;
     quint32 column;
 
+    void initGlobal(const QString *id, quint32 line, quint32 column);
     void init(const QString *id, quint32 line, quint32 column);
     void init(Builtin builtin, quint32 line, quint32 column);
 
@@ -741,6 +743,8 @@ struct BasicBlock {
     Name *NAME(const QString &id, quint32 line, quint32 column);
     Name *NAME(Name::Builtin builtin, quint32 line, quint32 column);
 
+    Name *GLOBALNAME(const QString &id, quint32 line, quint32 column);
+
     Closure *CLOSURE(Function *function);
 
     Expr *UNOP(AluOp op, Temp *expr);
diff --git a/src/v4/qv4lookup.cpp b/src/v4/qv4lookup.cpp
index 991ab2b617..76e1c415ca 100644
--- a/src/v4/qv4lookup.cpp
+++ b/src/v4/qv4lookup.cpp
@@ -129,6 +129,71 @@ void Lookup::lookupProperty2(Lookup *l, ExecutionContext *ctx, Value *result, co
     lookupPropertyGeneric(l, ctx, result, object);
 }
 
+void Lookup::lookupGlobalGeneric(Lookup *l, ExecutionContext *ctx, Value *result)
+{
+    Object *o = ctx->engine->globalObject;
+    PropertyAttributes attrs;
+    Property *p = l->lookup(o, &attrs);
+    if (p) {
+        if (attrs.isData()) {
+            if (l->level == 0)
+                l->lookupGlobal = lookupGlobal0;
+            else if (l->level == 1)
+                l->lookupGlobal = lookupGlobal1;
+            else if (l->level == 2)
+                l->lookupGlobal = lookupGlobal2;
+            *result = p->value;
+            return;
+        } else {
+            Value res = o->getValue(ctx, p, attrs);
+            if (result)
+                *result = res;
+            return;
+        }
+    }
+    ctx->throwReferenceError(Value::fromString(l->name));
+}
+
+void Lookup::lookupGlobal0(Lookup *l, ExecutionContext *ctx, Value *result)
+{
+    Object *o = ctx->engine->globalObject;
+    if (l->classList[0] == o->internalClass) {
+        *result = o->memberData[l->index].value;
+        return;
+    }
+    l->lookupGlobal = lookupGlobalGeneric;
+    lookupGlobalGeneric(l, ctx, result);
+}
+
+void Lookup::lookupGlobal1(Lookup *l, ExecutionContext *ctx, Value *result)
+{
+    Object *o = ctx->engine->globalObject;
+    if (l->classList[0] == o->internalClass &&
+        l->classList[1] == o->prototype->internalClass) {
+        *result = o->prototype->memberData[l->index].value;
+        return;
+    }
+    l->lookupGlobal = lookupGlobalGeneric;
+    lookupGlobalGeneric(l, ctx, result);
+}
+
+void Lookup::lookupGlobal2(Lookup *l, ExecutionContext *ctx, Value *result)
+{
+    Object *o = ctx->engine->globalObject;
+    if (l->classList[0] == o->internalClass) {
+        o = o->prototype;
+        if (l->classList[1] == o->internalClass) {
+            o = o->prototype;
+            if (l->classList[2] == o->internalClass) {
+                *result = o->prototype->memberData[l->index].value;
+                return;
+            }
+        }
+    }
+    l->lookupGlobal = lookupGlobalGeneric;
+    lookupGlobalGeneric(l, ctx, result);
+}
+
 }
 }
 
diff --git a/src/v4/qv4lookup.h b/src/v4/qv4lookup.h
index c51940ac2d..c287c97124 100644
--- a/src/v4/qv4lookup.h
+++ b/src/v4/qv4lookup.h
@@ -55,7 +55,10 @@ namespace VM {
 
 struct Lookup {
     enum { Size = 4 };
-    void (*lookupProperty)(Lookup *l, ExecutionContext *ctx, Value *result, const Value &object);
+    union {
+        void (*lookupProperty)(Lookup *l, ExecutionContext *ctx, Value *result, const Value &object);
+        void (*lookupGlobal)(Lookup *l, ExecutionContext *ctx, Value *result);
+    };
     InternalClass *classList[Size];
     int level;
     uint index;
@@ -66,6 +69,11 @@ struct Lookup {
     static void lookupProperty1(Lookup *l, ExecutionContext *ctx, Value *result, const Value &object);
     static void lookupProperty2(Lookup *l, ExecutionContext *ctx, Value *result, const Value &object);
 
+    static void lookupGlobalGeneric(Lookup *l, ExecutionContext *ctx, Value *result);
+    static void lookupGlobal0(Lookup *l, ExecutionContext *ctx, Value *result);
+    static void lookupGlobal1(Lookup *l, ExecutionContext *ctx, Value *result);
+    static void lookupGlobal2(Lookup *l, ExecutionContext *ctx, Value *result);
+
     Property *lookup(Object *obj, PropertyAttributes *attrs) {
         int i = 0;
         while (i < level && obj && obj->internalClass == classList[i]) {
diff --git a/src/v4/qv4runtime.cpp b/src/v4/qv4runtime.cpp
index b6a7dd6c99..8aac271f91 100644
--- a/src/v4/qv4runtime.cpp
+++ b/src/v4/qv4runtime.cpp
@@ -721,9 +721,14 @@ void __qmljs_get_activation_property(ExecutionContext *ctx, Value *result, Strin
     *result = ctx->getProperty(name);
 }
 
+void __qmljs_get_global_lookup(ExecutionContext *ctx, Value *result, int lookupIndex)
+{
+    Lookup *l = ctx->lookups + lookupIndex;
+    l->lookupGlobal(l, ctx, result);
+}
+
 void __qmljs_get_property_lookup(ExecutionContext *ctx, Value *result, const Value &object, int lookupIndex)
 {
-    Value res;
     Lookup *l = ctx->lookups + lookupIndex;
     l->lookupProperty(l, ctx, result, object);
 }
@@ -820,6 +825,31 @@ Bool __qmljs_strict_equal(const Value &x, const Value &y, ExecutionContext *ctx)
     return false;
 }
 
+
+void __qmljs_call_global_lookup(ExecutionContext *context, Value *result, uint index, Value *args, int argc)
+{
+    Lookup *l = context->lookups + index;
+    Value v;
+    l->lookupGlobal(l, context, &v);
+    FunctionObject *o = v.asFunctionObject();
+    if (!o)
+        context->throwTypeError();
+
+    Value thisObject = Value::undefinedValue();
+
+    if (o == context->engine->evalFunction && l->name->isEqualTo(context->engine->id_eval)) {
+        Value res = static_cast<EvalFunction *>(o)->evalCall(context, thisObject, args, argc, true);
+        if (result)
+            *result = res;
+        return;
+    }
+
+    Value res = o->call(context, thisObject, args, argc);
+    if (result)
+        *result = res;
+}
+
+
 void __qmljs_call_activation_property(ExecutionContext *context, Value *result, String *name, Value *args, int argc)
 {
     Object *base;
diff --git a/src/v4/qv4runtime.h b/src/v4/qv4runtime.h
index 8640c829df..8487244a72 100644
--- a/src/v4/qv4runtime.h
+++ b/src/v4/qv4runtime.h
@@ -166,6 +166,8 @@ void __qmljs_set_property(ExecutionContext *ctx, const Value &object, String *na
 void __qmljs_get_property(ExecutionContext *ctx, Value *result, const Value &object, String *name);
 void __qmljs_get_activation_property(ExecutionContext *ctx, Value *result, String *name);
 
+void __qmljs_get_global_lookup(ExecutionContext *ctx, Value *result, int lookupIndex);
+void __qmljs_call_global_lookup(ExecutionContext *context, Value *result, uint index, Value *args, int argc);
 void __qmljs_get_property_lookup(ExecutionContext *ctx, Value *result, const Value &object, int lookupIndex);
 void __qmljs_set_property_lookup(ExecutionContext *ctx, const Value &object, int lookupIndex, const Value &value);