Bug 1057082 - Part 2 - Fix JitcodeGlobalEntry comparison function and add helper debug methods. r=luke

js/src/jit/JitcodeMap.cpp

@@ -123,7 +123,24 @@ JitcodeGlobalEntry::compare(const JitcodeGlobalEntry &ent1, const JitcodeGlobalE
     // Ensure no overlaps for non-query lookups.
     JS_ASSERT_IF(!ent1.isQuery() && !ent2.isQuery(), !ent1.overlapsWith(ent2));
 
-    return ComparePointers(ent1.nativeStartAddr(), ent2.nativeStartAddr());
+    // For two non-query entries, just comapare the start addresses.
+    if (!ent1.isQuery() && !ent2.isQuery())
+        return ComparePointers(ent1.nativeStartAddr(), ent2.nativeStartAddr());
+
+    void *ptr = ent1.isQuery() ? ent1.nativeStartAddr() : ent2.nativeStartAddr();
+    const JitcodeGlobalEntry &ent = ent1.isQuery() ? ent2 : ent1;
+    int flip = ent1.isQuery() ? 1 : -1;
+
+    if (ent.startsBelowPointer(ptr)) {
+        if (ent.endsAbovePointer(ptr))
+            return 0;
+
+        // query ptr > entry
+        return flip * 1;
+    }
+
+    // query ptr < entry
+    return flip * -1;
 }
 
 bool