diff --git a/c2me-opts-natives-math/src/main/java/com/ishland/c2me/opts/natives_math/common/Bindings.java b/c2me-opts-natives-math/src/main/java/com/ishland/c2me/opts/natives_math/common/Bindings.java
index 3ad803b7d..e94fbc2af 100644
--- a/c2me-opts-natives-math/src/main/java/com/ishland/c2me/opts/natives_math/common/Bindings.java
+++ b/c2me-opts-natives-math/src/main/java/com/ishland/c2me/opts/natives_math/common/Bindings.java
@@ -78,6 +78,9 @@ public static float c2me_natives_end_islands_sample(MemorySegment data, int x, i
     }
 
     public static float c2me_natives_end_islands_sample(long data_ptr, int x, int z) {
+        if ((int) (x * x + z * z) < 0) { // workaround some compiler bugs
+            return Float.NaN;
+        }
         try {
             return (float) MH_c2me_natives_end_islands_sample_ptr.invokeExact(data_ptr, x, z);
         } catch (Throwable e) {
diff --git a/src/jmh/java/natives/accuracy/AbstractAccuracy.java b/src/jmh/java/natives/accuracy/AbstractAccuracy.java
index f14f2b715..3307dd194 100644
--- a/src/jmh/java/natives/accuracy/AbstractAccuracy.java
+++ b/src/jmh/java/natives/accuracy/AbstractAccuracy.java
@@ -10,34 +10,58 @@ public abstract class AbstractAccuracy {
 
     protected final ISATarget[] targets;
     protected final MethodHandle[] MHs;
-    protected final int[] maxUlp;
+    protected final long[] maxUlp;
 
     protected AbstractAccuracy(ISATarget[] targets, MethodHandle template, String prefix) {
         this.targets = Arrays.stream(targets).filter(ISATarget::isNativelySupported).toArray(ISATarget[]::new);
         this.MHs = Arrays.stream(this.targets)
                 .map(isaTarget -> template.bindTo(NativeLoader.lookup.find(prefix + isaTarget.getSuffix()).get()))
                 .toArray(MethodHandle[]::new);
-        this.maxUlp = new int[this.targets.length];
+        this.maxUlp = new long[this.targets.length];
     }
 
-    protected static int ulpDistance(double original, double that) {
-        int dist = 0;
+    protected static long ulpDistance(double original, double that) {
+        long dist = 0;
+        if (original > that) {
+            double tmp = that;
+            that = original;
+            original = tmp;
+        }
         while (that > original) {
             that = Math.nextAfter(that, original);
             dist ++;
         }
+        if (dist == 0 && !equals(original, that)) {
+            return Long.MAX_VALUE;
+        }
         return dist;
     }
 
-    protected static int ulpDistance(float original, float that) {
-        int dist = 0;
+    private static boolean equals(double original, double that) {
+        return (Double.isNaN(original) && Double.isNaN(that)) || original == that;
+    }
+
+    protected static long ulpDistance(float original, float that) {
+        long dist = 0;
+        if (original > that) {
+            float tmp = that;
+            that = original;
+            original = tmp;
+        }
         while (that > original) {
             that = Math.nextAfter(that, original);
             dist ++;
         }
+        if (dist == 0 && !equals(original, that)) {
+            return Long.MAX_VALUE;
+        }
         return dist;
     }
 
+    private static boolean equals(float original, float that) {
+        return (Float.isNaN(original) && Float.isNaN(that)) || original == that;
+    }
+
     protected void printUlps() {
         for (int i = 0; i < this.maxUlp.length; i++) {
             System.out.println(String.format("%s: max error %d ulps", this.targets[i], this.maxUlp[i]));
diff --git a/src/jmh/java/natives/accuracy/DoublePerlinNoiseAccuracy.java b/src/jmh/java/natives/accuracy/DoublePerlinNoiseAccuracy.java
index bd342f5e2..61a41776e 100644
--- a/src/jmh/java/natives/accuracy/DoublePerlinNoiseAccuracy.java
+++ b/src/jmh/java/natives/accuracy/DoublePerlinNoiseAccuracy.java
@@ -49,7 +49,7 @@ private void loopBody() {
         double original = invokeVanilla(x, y, z);
         for (int i = 0; i < this.MHs.length; i ++) {
             double actual = invokeNative(this.MHs[i], x, y, z);
-            int ulpDiff = ulpDistance(original, actual);
+            long ulpDiff = ulpDistance(original, actual);
             if (ulpDiff > this.maxUlp[i]) {
                 this.maxUlp[i] = ulpDiff;
                 System.out.println(String.format("%s: new max error %d ulps at x=%.18g, y=%.18g, z=%.18g (expected %.18g but got %.18g)", this.targets[i], ulpDiff, x, y, z, original, actual));
diff --git a/src/jmh/java/natives/accuracy/EndIslandsAccuracy.java b/src/jmh/java/natives/accuracy/EndIslandsAccuracy.java
index 610eb19e9..e28176590 100644
--- a/src/jmh/java/natives/accuracy/EndIslandsAccuracy.java
+++ b/src/jmh/java/natives/accuracy/EndIslandsAccuracy.java
@@ -30,6 +30,9 @@ protected EndIslandsAccuracy() {
     }
 
     private float invokeNative(MethodHandle handle, int x, int z) {
+        if ((int) (x * x + z * z) < 0) {
+            return Float.NaN;
+        }
         try {
             return (float) handle.invokeExact(nativeSamplerPtr, x, z);
         } catch (Throwable e) {
@@ -48,7 +51,7 @@ private void loopBody() {
         float original = invokeVanilla(x, z);
         for (int i = 0; i < this.MHs.length; i ++) {
             float actual = invokeNative(this.MHs[i], x, z);
-            int ulpDiff = ulpDistance(original, actual);
+            long ulpDiff = ulpDistance(original, actual);
             if (ulpDiff > this.maxUlp[i]) {
                 this.maxUlp[i] = ulpDiff;
                 System.out.println(String.format("%s: new max error %d ulps at x=%d, z=%d (expected %.10g but got %.10g)", this.targets[i], ulpDiff, x, z, original, actual));
diff --git a/src/jmh/java/natives/accuracy/InterpolatedNoiseAccuracy.java b/src/jmh/java/natives/accuracy/InterpolatedNoiseAccuracy.java
index 23a6c8237..7379536ee 100644
--- a/src/jmh/java/natives/accuracy/InterpolatedNoiseAccuracy.java
+++ b/src/jmh/java/natives/accuracy/InterpolatedNoiseAccuracy.java
@@ -43,7 +43,7 @@ private void loopBody() {
         double original = invokeVanilla(x, y, z);
         for (int i = 0; i < this.MHs.length; i ++) {
             double actual = invokeNative(this.MHs[i], x, y, z);
-            int ulpDiff = ulpDistance(original, actual);
+            long ulpDiff = ulpDistance(original, actual);
             if (ulpDiff > this.maxUlp[i]) {
                 this.maxUlp[i] = ulpDiff;
                 System.out.println(String.format("%s: new max error %d ulps at x=%.18g, y=%.18g, z=%.18g (expected %.18g but got %.18g)", this.targets[i], ulpDiff, x, y, z, original, actual));