diff -r 000000000000 -r 6474c204b198 js/src/jit/JitCommon.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit/JitCommon.h	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,46 @@
+/* -*- 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_JitCommon_h
+#define jit_JitCommon_h
+
+// Various macros used by all JITs, including YARR.
+
+#ifdef JS_ARM_SIMULATOR
+#include "jit/arm/Simulator-arm.h"
+
+// Call into cross-jitted code by following the ABI of the simulated architecture.
+#define CALL_GENERATED_CODE(entry, p0, p1, p2, p3, p4, p5, p6, p7)     \
+    (js::jit::Simulator::Current()->call(                              \
+        JS_FUNC_TO_DATA_PTR(uint8_t *, entry), 8, p0, p1, p2, p3, p4, p5, p6, p7) & 0xffffffff)
+
+#define CALL_GENERATED_YARR_CODE3(entry, p0, p1, p2)     \
+    js::jit::Simulator::Current()->call(JS_FUNC_TO_DATA_PTR(uint8_t *, entry), 3, p0, p1, p2)
+
+#define CALL_GENERATED_YARR_CODE4(entry, p0, p1, p2, p3) \
+    js::jit::Simulator::Current()->call(JS_FUNC_TO_DATA_PTR(uint8_t *, entry), 4, p0, p1, p2, p3)
+
+#define CALL_GENERATED_ASMJS(entry, p0, p1)              \
+    (Simulator::Current()->call(JS_FUNC_TO_DATA_PTR(uint8_t *, entry), 2, p0, p1) & 0xffffffff)
+
+#else
+
+// Call into jitted code by following the ABI of the native architecture.
+#define CALL_GENERATED_CODE(entry, p0, p1, p2, p3, p4, p5, p6, p7)   \
+  entry(p0, p1, p2, p3, p4, p5, p6, p7)
+
+#define CALL_GENERATED_YARR_CODE3(entry, p0, p1, p2)                 \
+  entry(p0, p1, p2)
+
+#define CALL_GENERATED_YARR_CODE4(entry, p0, p1, p2, p3)             \
+  entry(p0, p1, p2, p3)
+
+#define CALL_GENERATED_ASMJS(entry, p0, p1)                          \
+  entry(p0, p1)
+
+#endif
+
+#endif // jit_JitCommon_h