--- a/src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.core.aarch64/src/org/graalvm/compiler/core/aarch64/AArch64ReadReplacementPhase.java	Thu Jul 25 11:44:37 2019 -0700
+++ b/src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.core.aarch64/src/org/graalvm/compiler/core/aarch64/AArch64ReadReplacementPhase.java	Thu Jul 25 17:35:58 2019 -0400
@@ -49,7 +49,7 @@
             if (node instanceof ReadNode) {
                 ReadNode readNode = (ReadNode) node;
                 if (readNode.hasExactlyOneUsage()) {
-                    Node usage = readNode.getUsageAt(0);
+                    Node usage = readNode.usages().first();
                     if (usage instanceof ZeroExtendNode || usage instanceof SignExtendNode) {
                         AArch64ReadNode.replace(readNode);
                     }