| ... | ... | @@ -633,30 +633,6 @@ pub fn logl(x: c_longdouble) callconv(.c) c_longdouble { |
| 633 | 633 | } |
| 634 | 634 | } |
| 635 | 635 | |
| 636 | | /// Returns (f, k) such that x = f * 2^k and f in [1,2). |
| 637 | | /// Asserts that x is finite and positive. |
| 638 | | pub fn frexp2(x: f128) math.Frexp(f128) { |
| 639 | | std.debug.assert(math.isFinite(x)); |
| 640 | | std.debug.assert(x > 0.0); |
| 641 | | |
| 642 | | const bits: u128 = @bitCast(x); |
| 643 | | const uexp: i32 = @intCast(bits >> 112); |
| 644 | | |
| 645 | | std.debug.assert(uexp >= 0); |
| 646 | | |
| 647 | | if (uexp == 0) { |
| 648 | | const shift: u7 = @intCast(@clz(bits) - 15); |
| 649 | | |
| 650 | | const exp = -@as(i32, shift) - 0x3ffe; |
| 651 | | const frac: f128 = @bitCast((bits << shift) | (0x3fff << 112)); |
| 652 | | return .{ .significand = frac, .exponent = exp }; |
| 653 | | } |
| 654 | | |
| 655 | | const exp = uexp - 0x3fff; |
| 656 | | const frac: f128 = @bitCast((0x3fff << 112) | ((bits << 16) >> 16)); |
| 657 | | return .{ .significand = frac, .exponent = exp }; |
| 658 | | } |
| 659 | | |
| 660 | 636 | test "logf() special" { |
| 661 | 637 | try expectEqual(logf(0.0), -math.inf(f32)); |
| 662 | 638 | try expectEqual(logf(-0.0), -math.inf(f32)); |
Christophe Delage <christ@ophe.net> 2026-05-29 14:01:12+02:00
lib