d

2026-08-27 20:48:54 +00:00 · 2026-07-08 17:55:14 -04:00
parent 848e056bb8
commit d1fec88769
23 changed files with 1189 additions and 149 deletions
@@ -0,0 +1,74 @@
+package simdbench;
+
+import jdk.incubator.vector.DoubleVector;
+import jdk.incubator.vector.IntVector;
+import jdk.incubator.vector.VectorMask;
+import jdk.incubator.vector.VectorOperators;
+import jdk.incubator.vector.VectorShape;
+import jdk.incubator.vector.VectorSpecies;
+
+public final class VectorSimdKernels implements SimdKernels {
+    private static final VectorSpecies<Double> DOUBLE_SPECIES = DoubleVector.SPECIES_PREFERRED;
+    private static final VectorSpecies<Integer> INT_SPECIES = VectorSpecies.of(int.class, VectorShape.forBitSize(DOUBLE_SPECIES.length() * Integer.SIZE));
+
+    @Override
+    public String describe() {
+        return DOUBLE_SPECIES.length() + "x64-bit lanes, " + DOUBLE_SPECIES.vectorShape();
+    }
+
+    @Override
+    public void roundToInt(double[] source, int[] target, int length) {
+        int lanes = DOUBLE_SPECIES.length();
+        int bound = DOUBLE_SPECIES.loopBound(length);
+        int index = 0;
+        for (; index < bound; index += lanes) {
+            DoubleVector shifted = DoubleVector.fromArray(DOUBLE_SPECIES, source, index).add(0.5D);
+            IntVector truncated = (IntVector) shifted.convertShape(VectorOperators.D2I, INT_SPECIES, 0);
+            DoubleVector truncatedBack = (DoubleVector) truncated.convertShape(VectorOperators.I2D, DOUBLE_SPECIES, 0);
+            VectorMask<Integer> needsDecrement = shifted.lt(truncatedBack).cast(INT_SPECIES);
+            truncated.sub(1, needsDecrement).intoArray(target, index);
+        }
+
+        for (; index < length; index++) {
+            target[index] = (int) Math.round(source[index]);
+        }
+    }
+
+    @Override
+    public double sum(double[] values, int length) {
+        int lanes = DOUBLE_SPECIES.length();
+        int bound = DOUBLE_SPECIES.loopBound(length);
+        DoubleVector accumulator = DoubleVector.zero(DOUBLE_SPECIES);
+        int index = 0;
+        for (; index < bound; index += lanes) {
+            accumulator = accumulator.add(DoubleVector.fromArray(DOUBLE_SPECIES, values, index));
+        }
+
+        double total = accumulator.reduceLanes(VectorOperators.ADD);
+        for (; index < length; index++) {
+            total += values[index];
+        }
+
+        return total;
+    }
+
+    @Override
+    public double max(double[] values, int length) {
+        int lanes = DOUBLE_SPECIES.length();
+        int bound = DOUBLE_SPECIES.loopBound(length);
+        DoubleVector accumulator = DoubleVector.broadcast(DOUBLE_SPECIES, Double.NEGATIVE_INFINITY);
+        int index = 0;
+        for (; index < bound; index += lanes) {
+            accumulator = accumulator.max(DoubleVector.fromArray(DOUBLE_SPECIES, values, index));
+        }
+
+        double best = accumulator.reduceLanes(VectorOperators.MAX);
+        for (; index < length; index++) {
+            if (values[index] > best) {
+                best = values[index];
+            }
+        }
+
+        return best;
+    }
+}