diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/ion/bug754713-2.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/ion/bug754713-2.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,29 @@
+// Don't eliminate a phi if it has no SSA uses but its value is still
+// observable in the interpreter.
+var t1 = 100;
+function test1(x) {
+    // g(x) is inlined with --ion-eager, but don't mark the phi
+    // for x as unused.
+    for (var i = 0; i < 90; i++) {
+        f1(x);
+        if (i >= 80)
+            t1;
+    }
+}
+
+function f1(x) {};
+test1(2);
+
+var t2 = 100;
+function test2(g) {
+    // g(x) is inlined with --ion-eager, but don't mark the phi
+    // for g as unused.
+    for (var i = 0; i < 90; i++) {
+        g();
+        if (i >= 80)
+            t2;
+    }
+}
+
+function f2() {};
+test2(f2);