| ... | ... | @@ -5,12 +5,18 @@ const assert = std.debug.assert; |
| 5 | 5 | pub fn signbit(x: var) bool { |
| 6 | 6 | const T = @typeOf(x); |
| 7 | 7 | return switch (T) { |
| 8 | f16 => signbit16(x), |
| 8 | 9 | f32 => signbit32(x), |
| 9 | 10 | f64 => signbit64(x), |
| 10 | 11 | else => @compileError("signbit not implemented for " ++ @typeName(T)), |
| 11 | 12 | }; |
| 12 | 13 | } |
| 13 | 14 | |
| 15 | fn signbit16(x: f16) bool { |
| 16 | const bits = @bitCast(u16, x); |
| 17 | return bits >> 15 != 0; |
| 18 | } |
| 19 | |
| 14 | 20 | fn signbit32(x: f32) bool { |
| 15 | 21 | const bits = @bitCast(u32, x); |
| 16 | 22 | return bits >> 31 != 0; |
| ... | ... | @@ -22,10 +28,16 @@ fn signbit64(x: f64) bool { |
| 22 | 28 | } |
| 23 | 29 | |
| 24 | 30 | test "math.signbit" { |
| 31 | assert(signbit(f16(4.0)) == signbit16(4.0)); |
| 25 | 32 | assert(signbit(f32(4.0)) == signbit32(4.0)); |
| 26 | 33 | assert(signbit(f64(4.0)) == signbit64(4.0)); |
| 27 | 34 | } |
| 28 | 35 | |
| 36 | test "math.signbit16" { |
| 37 | assert(!signbit16(4.0)); |
| 38 | assert(signbit16(-3.0)); |
| 39 | } |
| 40 | |
| 29 | 41 | test "math.signbit32" { |
| 30 | 42 | assert(!signbit32(4.0)); |
| 31 | 43 | assert(signbit32(-3.0)); |
Ben Noordhuis <info@bnoordhuis.nl> 2018-06-30 01:44:54+02:00
std