--- old/src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.hotspot/src/org/graalvm/compiler/hotspot/CompilationTask.java	2019-05-14 01:06:03.992397372 +0200
+++ new/src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.hotspot/src/org/graalvm/compiler/hotspot/CompilationTask.java	2019-05-14 01:06:03.588394426 +0200
@@ -56,6 +56,7 @@
 import jdk.vm.ci.hotspot.HotSpotJVMCIRuntime;
 import jdk.vm.ci.hotspot.HotSpotNmethod;
 import jdk.vm.ci.hotspot.HotSpotResolvedJavaMethod;
+import jdk.vm.ci.meta.ResolvedJavaMethod;
 import jdk.vm.ci.runtime.JVMCICompiler;
 
 public class CompilationTask {
@@ -169,7 +170,13 @@
             }
             stats.finish(method, installedCode);
             if (result != null) {
-                return HotSpotCompilationRequestResult.success(result.getBytecodeSize() - method.getCodeSize());
+                // For compilation of substitutions the method in the compilation request might be
+                // different than the actual method parsed. The root of the compilation will always
+                // be the first method in the methods list, so use that instead.
+                ResolvedJavaMethod rootMethod = result.getMethods()[0];
+                int inlinedBytecodes = result.getBytecodeSize() - rootMethod.getCodeSize();
+                assert inlinedBytecodes >= 0 : rootMethod + " " + method;
+                return HotSpotCompilationRequestResult.success(inlinedBytecodes);
             }
             return null;
         }