1 files changed, 66 insertions, 0 deletions
diff --git a/js/src/jit/CalleeToken.h b/js/src/jit/CalleeToken.h
new file mode 100644
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+++ b/js/src/jit/CalleeToken.h
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+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * vim: set ts=8 sts=2 et sw=2 tw=80:
+ * 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_CalleeToken_h
+#define jit_CalleeToken_h
+
+#include "mozilla/Assertions.h"
+
+#include <stdint.h>
+
+#include "js/TypeDecls.h"
+
+class JS_PUBLIC_API JSTracer;
+
+namespace js::jit {
+
+using CalleeToken = void*;
+
+enum CalleeTokenTag {
+  CalleeToken_Function = 0x0,  // untagged
+  CalleeToken_FunctionConstructing = 0x1,
+  CalleeToken_Script = 0x2
+};
+
+// Any CalleeToken with this bit set must be CalleeToken_Script.
+static const uintptr_t CalleeTokenScriptBit = CalleeToken_Script;
+
+static const uintptr_t CalleeTokenMask = ~uintptr_t(0x3);
+
+static inline CalleeTokenTag GetCalleeTokenTag(CalleeToken token) {
+  CalleeTokenTag tag = CalleeTokenTag(uintptr_t(token) & 0x3);
+  MOZ_ASSERT(tag <= CalleeToken_Script);
+  return tag;
+}
+static inline CalleeToken CalleeToToken(JSFunction* fun, bool constructing) {
+  CalleeTokenTag tag =
+      constructing ? CalleeToken_FunctionConstructing : CalleeToken_Function;
+  return CalleeToken(uintptr_t(fun) | uintptr_t(tag));
+}
+static inline CalleeToken CalleeToToken(JSScript* script) {
+  return CalleeToken(uintptr_t(script) | uintptr_t(CalleeToken_Script));
+}
+static inline bool CalleeTokenIsFunction(CalleeToken token) {
+  CalleeTokenTag tag = GetCalleeTokenTag(token);
+  return tag == CalleeToken_Function || tag == CalleeToken_FunctionConstructing;
+}
+static inline bool CalleeTokenIsConstructing(CalleeToken token) {
+  return GetCalleeTokenTag(token) == CalleeToken_FunctionConstructing;
+}
+static inline JSFunction* CalleeTokenToFunction(CalleeToken token) {
+  MOZ_ASSERT(CalleeTokenIsFunction(token));
+  return (JSFunction*)(uintptr_t(token) & CalleeTokenMask);
+}
+static inline JSScript* CalleeTokenToScript(CalleeToken token) {
+  MOZ_ASSERT(GetCalleeTokenTag(token) == CalleeToken_Script);
+  return (JSScript*)(uintptr_t(token) & CalleeTokenMask);
+}
+
+CalleeToken TraceCalleeToken(JSTracer* trc, CalleeToken token);
+
+} /* namespace js::jit */
+
+#endif /* jit_CalleeToken_h */