Merge r242299 - [JSC] Fix FTL build on ARM32_64 by adding stubs for J…

…SRopeString::offsetOfXXX

https://bugs.webkit.org/show_bug.cgi?id=195235

Reviewed by Saam Barati.

This is a workaround until https://bugs.webkit.org/show_bug.cgi?id=195234 is done.

* runtime/JSString.h:

Source/JavaScriptCore/ChangeLog

@@ -1,3 +1,14 @@
+2019-03-01  Yusuke Suzuki  <ysuzuki@apple.com>
+
+        [JSC] Fix FTL build on ARM32_64 by adding stubs for JSRopeString::offsetOfXXX
+        https://bugs.webkit.org/show_bug.cgi?id=195235
+
+        Reviewed by Saam Barati.
+
+        This is a workaround until https://bugs.webkit.org/show_bug.cgi?id=195234 is done.
+
+        * runtime/JSString.h:
+
 2019-03-01  Yusuke Suzuki  <ysuzuki@apple.com>
 
         [JSC] Use runtime calls for DFG MakeRope if !CPU(ADDRESS64)

Source/JavaScriptCore/runtime/JSString.h

@@ -549,13 +549,22 @@ class JSRopeString final : public JSString {
 
 public:
     static ptrdiff_t offsetOfLength() { return OBJECT_OFFSETOF(JSRopeString, m_compactFibers) + CompactFibers::offsetOfLength(); } // 32byte width.
+    static ptrdiff_t offsetOfFiber0() { return offsetOfValue(); }
 #if CPU(ADDRESS64)
     static ptrdiff_t offsetOfFlags() { return offsetOfValue() + sizeof(uint16_t) * 3; } // 16byte width.
-    static ptrdiff_t offsetOfFiber0() { return offsetOfValue(); }
     static ptrdiff_t offsetOfFiber1Lower() { return OBJECT_OFFSETOF(JSRopeString, m_compactFibers) + CompactFibers::offsetOfFiber1Lower(); } // 32byte width.
     static ptrdiff_t offsetOfFiber1Upper() { return OBJECT_OFFSETOF(JSRopeString, m_compactFibers) + CompactFibers::offsetOfFiber1Upper(); } // 16byte width.
     static ptrdiff_t offsetOfFiber2Lower() { return OBJECT_OFFSETOF(JSRopeString, m_compactFibers) + CompactFibers::offsetOfFiber2Lower(); } // 32byte width.
     static ptrdiff_t offsetOfFiber2Upper() { return OBJECT_OFFSETOF(JSRopeString, m_compactFibers) + CompactFibers::offsetOfFiber2Upper(); } // 16byte width.
+#elif USE(JSVALUE64)
+    // FIXME: This is an temporary workaround to make JSC built on ARM64_32. Once we start calculating bits before storing them to JSRopeString,
+    // we do not need to have such a detailed information as an offset. After that, what we only need is offsetOfFiber0, offsetOfFiber1, and offsetOfFiber2.
+    // https://bugs.webkit.org/show_bug.cgi?id=195234
+    static ptrdiff_t offsetOfFlags() { ASSERT_NOT_REACHED(); return 0; }
+    static ptrdiff_t offsetOfFiber1Lower() { ASSERT_NOT_REACHED(); return 0; }
+    static ptrdiff_t offsetOfFiber1Upper() { ASSERT_NOT_REACHED(); return 0; }
+    static ptrdiff_t offsetOfFiber2Lower() { ASSERT_NOT_REACHED(); return 0; }
+    static ptrdiff_t offsetOfFiber2Upper() { ASSERT_NOT_REACHED(); return 0; }
 #endif
 
     static constexpr unsigned s_maxInternalRopeLength = 3;