1 files changed, 121 insertions, 0 deletions
diff --git a/winpr/test/TestIntrinsics.c b/winpr/test/TestIntrinsics.c
new file mode 100644
index 0000000..2198d67
--- /dev/null
+++ b/winpr/test/TestIntrinsics.c
@@ -0,0 +1,121 @@
+#include <winpr/crt.h>
+#include <winpr/sysinfo.h>
+#include <winpr/windows.h>
+
+#include <winpr/intrin.h>
+
+static BOOL g_LZCNT = FALSE;
+
+static INLINE UINT32 lzcnt_s(UINT32 x)
+{
+	if (!x)
+		return 32;
+
+	if (!g_LZCNT)
+	{
+		UINT32 y = 0;
+		int n = 32;
+		y = x >> 16;
+		if (y != 0)
+		{
+			n = n - 16;
+			x = y;
+		}
+		y = x >> 8;
+		if (y != 0)
+		{
+			n = n - 8;
+			x = y;
+		}
+		y = x >> 4;
+		if (y != 0)
+		{
+			n = n - 4;
+			x = y;
+		}
+		y = x >> 2;
+		if (y != 0)
+		{
+			n = n - 2;
+			x = y;
+		}
+		y = x >> 1;
+		if (y != 0)
+			return n - 2;
+		return n - x;
+	}
+
+	return __lzcnt(x);
+}
+
+static int test_lzcnt(void)
+{
+	if (lzcnt_s(0x1) != 31)
+	{
+		fprintf(stderr, "__lzcnt(0x1) != 31: %" PRIu32 "\n", __lzcnt(0x1));
+		return -1;
+	}
+
+	if (lzcnt_s(0xFF) != 24)
+	{
+		fprintf(stderr, "__lzcnt(0xFF) != 24\n");
+		return -1;
+	}
+
+	if (lzcnt_s(0xFFFF) != 16)
+	{
+		fprintf(stderr, "__lzcnt(0xFFFF) != 16\n");
+		return -1;
+	}
+
+	if (lzcnt_s(0xFFFFFF) != 8)
+	{
+		fprintf(stderr, "__lzcnt(0xFFFFFF) != 8\n");
+		return -1;
+	}
+
+	if (lzcnt_s(0xFFFFFFFF) != 0)
+	{
+		fprintf(stderr, "__lzcnt(0xFFFFFFFF) != 0\n");
+		return -1;
+	}
+
+	return 0;
+}
+
+static int test_lzcnt16(void)
+{
+	if (__lzcnt16(0x1) != 15)
+	{
+		fprintf(stderr, "__lzcnt16(0x1) != 15\n");
+		return -1;
+	}
+
+	if (__lzcnt16(0xFF) != 8)
+	{
+		fprintf(stderr, "__lzcnt16(0xFF) != 8\n");
+		return -1;
+	}
+
+	if (__lzcnt16(0xFFFF) != 0)
+	{
+		fprintf(stderr, "__lzcnt16(0xFFFF) != 0\n");
+		return -1;
+	}
+
+	return 0;
+}
+
+int TestIntrinsics(int argc, char* argv[])
+{
+
+	WINPR_UNUSED(argc);
+	WINPR_UNUSED(argv);
+
+	g_LZCNT = IsProcessorFeaturePresentEx(PF_EX_LZCNT);
+
+	printf("LZCNT available: %" PRId32 "\n", g_LZCNT);
+
+	// test_lzcnt16();
+	return test_lzcnt();
+}