Add m-esr52 at 52.6.0

1 files changed, 231 insertions, 0 deletions

diff --git a/js/src/vm/GeneratorObject.h b/js/src/vm/GeneratorObject.h
new file mode 100644
index 0000000000..ca1452b347
--- /dev/null
+++ b/js/src/vm/GeneratorObject.h
@@ -0,0 +1,231 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+ * vim: set ts=8 sts=4 et sw=4 tw=99:
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef vm_GeneratorObject_h
+#define vm_GeneratorObject_h
+
+#include "jscntxt.h"
+#include "jsobj.h"
+
+#include "vm/ArgumentsObject.h"
+#include "vm/ArrayObject.h"
+#include "vm/Stack.h"
+
+namespace js {
+
+class GeneratorObject : public NativeObject
+{
+  public:
+    // Magic values stored in the yield index slot when the generator is
+    // running or closing. See the yield index comment below.
+    static const int32_t YIELD_INDEX_RUNNING = INT32_MAX;
+    static const int32_t YIELD_INDEX_CLOSING = INT32_MAX - 1;
+
+    enum {
+        CALLEE_SLOT = 0,
+        ENV_CHAIN_SLOT,
+        ARGS_OBJ_SLOT,
+        EXPRESSION_STACK_SLOT,
+        YIELD_INDEX_SLOT,
+        NEWTARGET_SLOT,
+        RESERVED_SLOTS
+    };
+
+    enum ResumeKind { NEXT, THROW, CLOSE };
+
+  private:
+    static bool suspend(JSContext* cx, HandleObject obj, AbstractFramePtr frame, jsbytecode* pc,
+                        Value* vp, unsigned nvalues);
+
+  public:
+    static inline ResumeKind getResumeKind(jsbytecode* pc) {
+        MOZ_ASSERT(*pc == JSOP_RESUME);
+        unsigned arg = GET_UINT16(pc);
+        MOZ_ASSERT(arg <= CLOSE);
+        return static_cast<ResumeKind>(arg);
+    }
+
+    static inline ResumeKind getResumeKind(ExclusiveContext* cx, JSAtom* atom) {
+        if (atom == cx->names().next)
+            return NEXT;
+        if (atom == cx->names().throw_)
+            return THROW;
+        MOZ_ASSERT(atom == cx->names().close);
+        return CLOSE;
+    }
+
+    static JSObject* create(JSContext* cx, AbstractFramePtr frame);
+
+    static bool resume(JSContext* cx, InterpreterActivation& activation,
+                       HandleObject obj, HandleValue arg, ResumeKind resumeKind);
+
+    static bool initialSuspend(JSContext* cx, HandleObject obj, AbstractFramePtr frame, jsbytecode* pc) {
+        return suspend(cx, obj, frame, pc, nullptr, 0);
+    }
+
+    static bool normalSuspend(JSContext* cx, HandleObject obj, AbstractFramePtr frame, jsbytecode* pc,
+                              Value* vp, unsigned nvalues) {
+        return suspend(cx, obj, frame, pc, vp, nvalues);
+    }
+
+    static bool finalSuspend(JSContext* cx, HandleObject obj);
+
+    JSFunction& callee() const {
+        return getFixedSlot(CALLEE_SLOT).toObject().as<JSFunction>();
+    }
+    void setCallee(JSFunction& callee) {
+        setFixedSlot(CALLEE_SLOT, ObjectValue(callee));
+    }
+
+    JSObject& environmentChain() const {
+        return getFixedSlot(ENV_CHAIN_SLOT).toObject();
+    }
+    void setEnvironmentChain(JSObject& envChain) {
+        setFixedSlot(ENV_CHAIN_SLOT, ObjectValue(envChain));
+    }
+
+    bool hasArgsObj() const {
+        return getFixedSlot(ARGS_OBJ_SLOT).isObject();
+    }
+    ArgumentsObject& argsObj() const {
+        return getFixedSlot(ARGS_OBJ_SLOT).toObject().as<ArgumentsObject>();
+    }
+    void setArgsObj(ArgumentsObject& argsObj) {
+        setFixedSlot(ARGS_OBJ_SLOT, ObjectValue(argsObj));
+    }
+
+    bool hasExpressionStack() const {
+        return getFixedSlot(EXPRESSION_STACK_SLOT).isObject();
+    }
+    ArrayObject& expressionStack() const {
+        return getFixedSlot(EXPRESSION_STACK_SLOT).toObject().as<ArrayObject>();
+    }
+    void setExpressionStack(ArrayObject& expressionStack) {
+        setFixedSlot(EXPRESSION_STACK_SLOT, ObjectValue(expressionStack));
+    }
+    void clearExpressionStack() {
+        setFixedSlot(EXPRESSION_STACK_SLOT, NullValue());
+    }
+
+    bool isConstructing() const {
+        return getFixedSlot(NEWTARGET_SLOT).isObject();
+    }
+    const Value& newTarget() const {
+        return getFixedSlot(NEWTARGET_SLOT);
+    }
+    void setNewTarget(const Value& newTarget) {
+        setFixedSlot(NEWTARGET_SLOT, newTarget);
+    }
+
+
+    // The yield index slot is abused for a few purposes.  It's undefined if
+    // it hasn't been set yet (before the initial yield), and null if the
+    // generator is closed. If the generator is running, the yield index is
+    // YIELD_INDEX_RUNNING. If the generator is in that bizarre "closing"
+    // state, the yield index is YIELD_INDEX_CLOSING.
+    //
+    // If the generator is suspended, it's the yield index (stored as
+    // JSOP_INITIALYIELD/JSOP_YIELD operand) of the yield instruction that
+    // suspended the generator. The yield index can be mapped to the bytecode
+    // offset (interpreter) or to the native code offset (JIT).
+
+    bool isRunning() const {
+        MOZ_ASSERT(!isClosed());
+        return getFixedSlot(YIELD_INDEX_SLOT).toInt32() == YIELD_INDEX_RUNNING;
+    }
+    bool isClosing() const {
+        return getFixedSlot(YIELD_INDEX_SLOT).toInt32() == YIELD_INDEX_CLOSING;
+    }
+    bool isSuspended() const {
+        // Note: also update Baseline's IsSuspendedStarGenerator code if this
+        // changes.
+        MOZ_ASSERT(!isClosed());
+        static_assert(YIELD_INDEX_CLOSING < YIELD_INDEX_RUNNING,
+                      "test below should return false for YIELD_INDEX_RUNNING");
+        return getFixedSlot(YIELD_INDEX_SLOT).toInt32() < YIELD_INDEX_CLOSING;
+    }
+    void setRunning() {
+        MOZ_ASSERT(isSuspended());
+        setFixedSlot(YIELD_INDEX_SLOT, Int32Value(YIELD_INDEX_RUNNING));
+    }
+    void setClosing() {
+        MOZ_ASSERT(isSuspended());
+        setFixedSlot(YIELD_INDEX_SLOT, Int32Value(YIELD_INDEX_CLOSING));
+    }
+    void setYieldIndex(uint32_t yieldIndex) {
+        MOZ_ASSERT_IF(yieldIndex == 0, getFixedSlot(YIELD_INDEX_SLOT).isUndefined());
+        MOZ_ASSERT_IF(yieldIndex != 0, isRunning() || isClosing());
+        MOZ_ASSERT(yieldIndex < uint32_t(YIELD_INDEX_CLOSING));
+        setFixedSlot(YIELD_INDEX_SLOT, Int32Value(yieldIndex));
+        MOZ_ASSERT(isSuspended());
+    }
+    uint32_t yieldIndex() const {
+        MOZ_ASSERT(isSuspended());
+        return getFixedSlot(YIELD_INDEX_SLOT).toInt32();
+    }
+    bool isClosed() const {
+        return getFixedSlot(CALLEE_SLOT).isNull();
+    }
+    void setClosed() {
+        setFixedSlot(CALLEE_SLOT, NullValue());
+        setFixedSlot(ENV_CHAIN_SLOT, NullValue());
+        setFixedSlot(ARGS_OBJ_SLOT, NullValue());
+        setFixedSlot(EXPRESSION_STACK_SLOT, NullValue());
+        setFixedSlot(YIELD_INDEX_SLOT, NullValue());
+        setFixedSlot(NEWTARGET_SLOT, NullValue());
+    }
+
+    static size_t offsetOfCalleeSlot() {
+        return getFixedSlotOffset(CALLEE_SLOT);
+    }
+    static size_t offsetOfEnvironmentChainSlot() {
+        return getFixedSlotOffset(ENV_CHAIN_SLOT);
+    }
+    static size_t offsetOfArgsObjSlot() {
+        return getFixedSlotOffset(ARGS_OBJ_SLOT);
+    }
+    static size_t offsetOfYieldIndexSlot() {
+        return getFixedSlotOffset(YIELD_INDEX_SLOT);
+    }
+    static size_t offsetOfExpressionStackSlot() {
+        return getFixedSlotOffset(EXPRESSION_STACK_SLOT);
+    }
+    static size_t offsetOfNewTargetSlot() {
+        return getFixedSlotOffset(NEWTARGET_SLOT);
+    }
+};
+
+class LegacyGeneratorObject : public GeneratorObject
+{
+  public:
+    static const Class class_;
+
+    static bool close(JSContext* cx, HandleObject obj);
+};
+
+class StarGeneratorObject : public GeneratorObject
+{
+  public:
+    static const Class class_;
+};
+
+bool GeneratorThrowOrClose(JSContext* cx, AbstractFramePtr frame, Handle<GeneratorObject*> obj,
+                           HandleValue val, uint32_t resumeKind);
+void SetReturnValueForClosingGenerator(JSContext* cx, AbstractFramePtr frame);
+
+MOZ_MUST_USE bool
+CheckStarGeneratorResumptionValue(JSContext* cx, HandleValue v);
+
+} // namespace js
+
+template<>
+inline bool
+JSObject::is<js::GeneratorObject>() const
+{
+    return is<js::LegacyGeneratorObject>() || is<js::StarGeneratorObject>();
+}
+
+#endif /* vm_GeneratorObject_h */