detect fma

buildSrc/src/main/kotlin/Versions.kt

@@ -13,6 +13,7 @@ object Versions {
             const val apacheText = "1.9"
             const val apacheIO = "2.6"
             const val fastutil = "8.5.6"
+            const val cpuFeaturesJava = "1.0.1"
         }
     }
     

common/addons/config-noise-function/src/main/java/com/dfsek/terra/addons/noise/samplers/noise/PseudoErosionSampler.java

@@ -10,6 +10,8 @@ package com.dfsek.terra.addons.noise.samplers.noise;
 import com.dfsek.terra.api.noise.NoiseSampler;
 import com.dfsek.terra.api.util.MathUtil;
 
+import com.google.errorprone.annotations.InlineMe;
+
 import static com.dfsek.terra.addons.noise.samplers.noise.NoiseFunction.PRIME_X;
 import static com.dfsek.terra.addons.noise.samplers.noise.NoiseFunction.PRIME_Y;
 import static com.dfsek.terra.addons.noise.samplers.noise.NoiseFunction.hash;
@@ -229,6 +231,7 @@ public class PseudoErosionSampler implements NoiseSampler {
         this.cellularJitter = 0.43701595 * jitterModifier;
     }
     
+    
     public double getNoiseRaw(long sl, double x, double y) {
         int seed = (int) sl;
         double finalDistance = Double.MAX_VALUE;
@@ -248,8 +251,8 @@ public class PseudoErosionSampler implements NoiseSampler {
                 int gridYi = gridY + yi;
                 
                 int jitterIdx = hash(seed, gridXiPrimed, gridYi * PRIME_Y) & (255 << 1);
-                double cellX = Math.fma(RAND_VECS_2D[jitterIdx], cellularJitter, gridXi);
+                double cellX = MathUtil.fma(RAND_VECS_2D[jitterIdx], cellularJitter, gridXi);
-                double cellY = Math.fma(RAND_VECS_2D[jitterIdx | 1], cellularJitter, gridYi);
+                double cellY = MathUtil.fma(RAND_VECS_2D[jitterIdx | 1], cellularJitter, gridYi);
                 
                 // Transform to actual coordinates for lookup
                 double actualCellX = cellX * inverseFrequency;
@@ -322,7 +325,7 @@ public class PseudoErosionSampler implements NoiseSampler {
         double x2dx = x - x2;
         double y2dx = y - y2;
         
-        double dotProduct = Math.fma(ldy, y1dx, (ldx * x1dx));
+        double dotProduct = MathUtil.fma(ldy, y1dx, (ldx * x1dx));
         double lt = dotProduct * invLineLengthSquared; // Position along the line
         
         if (lt > 0) {
@@ -330,7 +333,7 @@ public class PseudoErosionSampler implements NoiseSampler {
         } else if (lt < -1) {
             return MathUtil.hypot(x2dx, y2dx); // Distance between point 2 and position
         } else {
-            double distance = Math.fma(ldy, x1dx, (-(ldx * y1dx))) * Math.sqrt(invLineLengthSquared);
+            double distance = MathUtil.fma(ldy, x1dx, (-(ldx * y1dx))) * Math.sqrt(invLineLengthSquared);
             return Math.abs(distance); // Distance from the line
         }
     }

common/api/build.gradle.kts

@@ -8,4 +8,8 @@ dependencies {
     
     api("com.github.ben-manes.caffeine:caffeine:3.1.0")
 
+    api("io.github.aecsocket", "cpu-features-jni", Versions.Libraries.Internal.cpuFeaturesJava)
+    api("io.github.aecsocket", "cpu-features-jni-natives-linux", Versions.Libraries.Internal.cpuFeaturesJava)
+    api("io.github.aecsocket", "cpu-features-jni-natives-windows", Versions.Libraries.Internal.cpuFeaturesJava)
+    api("io.github.aecsocket", "cpu-features-jni-natives-macos", Versions.Libraries.Internal.cpuFeaturesJava)
 }

common/api/src/main/java/com/dfsek/terra/api/util/MathUtil.java

@@ -7,6 +7,11 @@
 
 package com.dfsek.terra.api.util;
 
+import cpufeatures.CpuFeatures;
+import cpufeatures.aarch64.Aarch64Feature;
+import cpufeatures.arm.ArmFeature;
+import cpufeatures.x86.X86Feature;
+
 import java.util.List;
 
 
@@ -19,6 +24,26 @@ public final class MathUtil {
     private static final double degFull, degToIndex;
     private static final double[] sin, cos;
     
+    public static final boolean hasFMA;
+    
+    static {
+        boolean configHasFMA = false;
+        try {
+                CpuFeatures.load();
+                configHasFMA = switch (CpuFeatures.getArchitecture()) {
+                    case UNSUPPORTED -> false;
+                    case AARCH64 -> CpuFeatures.getAarch64Info().has(Aarch64Feature.ASIMD);
+                    case ARM -> CpuFeatures.getArmInfo().has(ArmFeature.NEON);
+                    case RISCV -> true;
+                    case X86 -> CpuFeatures.getX86Info().has(X86Feature.FMA3);
+                };
+        } catch (Throwable t) {
+            System.err.println("Failed to determine FMA support, assuming no FMA support");
+        }
+        hasFMA = configHasFMA;
+        System.out.println("FMA: " + configHasFMA);
+    }
+    
     static {
         SIN_BITS = 12;
         SIN_MASK = ~(-1 << SIN_BITS);
@@ -259,4 +284,12 @@ public final class MathUtil {
     public static double hypot(double x, double y) {
         return Math.sqrt(Math.pow(x, 2) + Math.pow(y, 2));
     }
+    
+    public static double fma(double a, double b, double c) {
+        if (hasFMA) {
+            return Math.fma(a, b, c);
+        } else {
+            return a * b + c;
+        }
+    }
 }