diff -r 000000000000 -r 6474c204b198 js/src/jit/RematerializedFrame.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit/RematerializedFrame.h	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,165 @@
+/* -*- 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 jit_RematerializedFrame_h
+#define jit_RematerializedFrame_h
+
+#ifdef JS_ION
+
+#include "jsfun.h"
+
+#include "jit/JitFrameIterator.h"
+
+#include "vm/Stack.h"
+
+namespace js {
+namespace jit {
+
+//
+// An optimized frame that has been rematerialized with values read out of
+// Snapshots.
+//
+class RematerializedFrame
+{
+    // See DebugScopes::updateLiveScopes.
+    bool prevUpToDate_;
+
+    // The fp of the top frame associated with this possibly inlined frame.
+    uint8_t *top_;
+
+    size_t frameNo_;
+    unsigned numActualArgs_;
+
+    JSScript *script_;
+    JSObject *scopeChain_;
+    ArgumentsObject *argsObj_;
+
+    Value returnValue_;
+    Value thisValue_;
+    Value slots_[1];
+
+    RematerializedFrame(JSContext *cx, uint8_t *top, InlineFrameIterator &iter);
+
+  public:
+    static RematerializedFrame *New(JSContext *cx, uint8_t *top, InlineFrameIterator &iter);
+
+    bool prevUpToDate() const {
+        return prevUpToDate_;
+    }
+    void setPrevUpToDate() {
+        prevUpToDate_ = true;
+    }
+
+    uint8_t *top() const {
+        return top_;
+    }
+    size_t frameNo() const {
+        return frameNo_;
+    }
+    bool inlined() const {
+        return frameNo_ > 0;
+    }
+
+    JSObject *scopeChain() const {
+        return scopeChain_;
+    }
+    bool hasCallObj() const {
+        return maybeFun() && fun()->isHeavyweight();
+    }
+    CallObject &callObj() const;
+
+    bool hasArgsObj() const {
+        return !!argsObj_;
+    }
+    ArgumentsObject &argsObj() const {
+        MOZ_ASSERT(hasArgsObj());
+        MOZ_ASSERT(script()->needsArgsObj());
+        return *argsObj_;
+    }
+
+    bool isFunctionFrame() const {
+        return !!script_->functionNonDelazifying();
+    }
+    bool isGlobalFrame() const {
+        return !isFunctionFrame();
+    }
+    bool isNonEvalFunctionFrame() const {
+        // Ion doesn't support eval frames.
+        return isFunctionFrame();
+    }
+
+    JSScript *script() const {
+        return script_;
+    }
+    JSFunction *fun() const {
+        MOZ_ASSERT(isFunctionFrame());
+        return script_->functionNonDelazifying();
+    }
+    JSFunction *maybeFun() const {
+        return isFunctionFrame() ? fun() : nullptr;
+    }
+    JSFunction *callee() const {
+        return fun();
+    }
+    Value calleev() const {
+        return ObjectValue(*fun());
+    }
+    Value &thisValue() {
+        return thisValue_;
+    }
+
+    unsigned numFormalArgs() const {
+        return maybeFun() ? fun()->nargs() : 0;
+    }
+    unsigned numActualArgs() const {
+        return numActualArgs_;
+    }
+
+    Value *argv() {
+        return slots_;
+    }
+    Value *locals() {
+        return slots_ + numActualArgs_;
+    }
+
+    Value &unaliasedVar(unsigned i, MaybeCheckAliasing checkAliasing = CHECK_ALIASING) {
+        JS_ASSERT_IF(checkAliasing, !script()->varIsAliased(i));
+        JS_ASSERT(i < script()->nfixed());
+        return locals()[i];
+    }
+    Value &unaliasedLocal(unsigned i, MaybeCheckAliasing checkAliasing = CHECK_ALIASING) {
+        JS_ASSERT(i < script()->nfixed());
+#ifdef DEBUG
+        CheckLocalUnaliased(checkAliasing, script(), i);
+#endif
+        return locals()[i];
+    }
+    Value &unaliasedFormal(unsigned i, MaybeCheckAliasing checkAliasing = CHECK_ALIASING) {
+        JS_ASSERT(i < numFormalArgs());
+        JS_ASSERT_IF(checkAliasing, !script()->argsObjAliasesFormals() &&
+                                    !script()->formalIsAliased(i));
+        return argv()[i];
+    }
+    Value &unaliasedActual(unsigned i, MaybeCheckAliasing checkAliasing = CHECK_ALIASING) {
+        JS_ASSERT(i < numActualArgs());
+        JS_ASSERT_IF(checkAliasing, !script()->argsObjAliasesFormals());
+        JS_ASSERT_IF(checkAliasing && i < numFormalArgs(), !script()->formalIsAliased(i));
+        return argv()[i];
+    }
+
+    Value returnValue() const {
+        return returnValue_;
+    }
+
+    void mark(JSTracer *trc);
+    void dump();
+};
+
+} // namespace jit
+} // namespace js
+
+#endif // JS_ION
+#endif // jit_RematerializedFrame_h