new32v2, an even faster solution.

1 files changed, 21 insertions, 0 deletions

diff --git a/src/new32v2.c b/src/new32v2.c
new file mode 100644
index 0000000..a755d6d
--- /dev/null
+++ b/src/new32v2.c
@@ -0,0 +1,21 @@
+#include <stdint.h>
+
+static const unsigned int divtab[244] = {
+	[1] = 0xffff + 1l,
+	[3] = 0x5555 + 1l,
+	[9] = 0x1c71 + 1l,
+	[27] = 0x097b + 1l,
+	[81] = 0x0329 + 1l,
+	[243] = 0x010d + 1l
+};
+
+#define FASTDIV(n, d) (((n) * (divtab[d])) >> 16)
+
+int new32v2(int i, int x, int y)
+{
+	int A;
+
+	A = FASTDIV(i, y);
+
+	return i + (x - 3 * FASTDIV(A + x, 3) + 3 * FASTDIV(A, 3)) * y;
+}