diff options
Diffstat (limited to 'src/global.zig')
| -rw-r--r-- | src/global.zig | 39 |
1 files changed, 39 insertions, 0 deletions
diff --git a/src/global.zig b/src/global.zig index 635e759ce..d67f93fb7 100644 --- a/src/global.zig +++ b/src/global.zig @@ -31,6 +31,45 @@ pub const path = @import("./resolver/resolve_path.zig"); pub const fmt = struct { pub usingnamespace std.fmt; + // https://lemire.me/blog/2021/06/03/computing-the-number-of-digits-of-an-integer-even-faster/ + pub fn fastDigitCount(x: u64) u64 { + const table = [_]u64{ + 4294967296, + 8589934582, + 8589934582, + 8589934582, + 12884901788, + 12884901788, + 12884901788, + 17179868184, + 17179868184, + 17179868184, + 21474826480, + 21474826480, + 21474826480, + 21474826480, + 25769703776, + 25769703776, + 25769703776, + 30063771072, + 30063771072, + 30063771072, + 34349738368, + 34349738368, + 34349738368, + 34349738368, + 38554705664, + 38554705664, + 38554705664, + 41949672960, + 41949672960, + 41949672960, + 42949672960, + 42949672960, + }; + return x + table[std.math.log2(x)] >> 32; + } + pub const SizeFormatter = struct { value: usize = 0, pub fn format(self: SizeFormatter, comptime _: []const u8, opts: fmt.FormatOptions, writer: anytype) !void { |