Add special memory allocator for Lua that should take some memory stress away from heavy scripting.

BBGE/bithacks.h

@@ -0,0 +1,84 @@
+#ifndef BITHACKS_H
+#define BITHACKS_H
+
+#ifdef _MSC_VER
+#  include <intrin.h>
+#endif
+
+namespace bithacks {
+
+typedef unsigned int uint32;
+typedef int int32;
+
+// floor to next power of 2
+inline uint32 flp2(uint32 x)
+{
+	x |= (x >> 1);
+	x |= (x >> 2);
+	x |= (x >> 4);
+	x |= (x >> 8);
+	x |= (x >> 16);
+	return x - (x >> 1);
+}
+
+// ceil to next power of 2
+inline uint32 clp2(uint32 x)
+{
+	--x;
+	x |= (x >> 1);
+	x |= (x >> 2);
+	x |= (x >> 4);
+	x |= (x >> 8);
+	x |= (x >> 16);
+	return x + 1;
+}
+
+inline uint32 popcnt(uint32 x)
+{
+	x -= ((x >> 1) & 0x55555555);
+	x = (((x >> 2) & 0x33333333) + (x & 0x33333333));
+	x = (((x >> 4) + x) & 0x0f0f0f0f);
+	x += (x >> 8);
+	x += (x >> 16);
+	return x & 0x0000003f;
+}
+
+inline uint32 ctz(uint32 x)
+{
+#ifdef __GNUC__
+	return __builtin_ctz(x);
+#elif defined(_MSC_VER) && defined(_M_IX86)
+	unsigned long r = 0;
+	_BitScanForward(&r, x);
+	return r;
+#else
+	return popcnt((x & -x) - 1);
+#endif
+}
+
+inline unsigned int clz(uint32 x)
+{
+#ifdef __GNUC__
+	return __builtin_clz(x);
+#elif defined(_MSC_VER) && defined(_M_IX86)
+	unsigned long r = 0;
+	_BitScanReverse(&r, x);
+	return r;
+#else
+	x |= (x >> 1);
+	x |= (x >> 2);
+	x |= (x >> 4);
+	x |= (x >> 8);
+	x |= (x >> 16);
+	return 32 - popcnt(x);
+#endif
+}
+
+
+
+
+
+
+}; // end namespace bithacks
+
+#endif