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| author | paoda <rekai@musuka.dev> | 2024-03-09 04:46:43 -0600 |
|---|---|---|
| committer | Veikka Tuominen <git@vexu.eu> | 2024-03-15 16:19:48 +0200 |
| commit | a4508ad7167513d178fd237e4cd361185800d05d (patch) | |
| tree | f12a04a17516bf6812cfd6afed82ae7a53dd603b /lib/std/math.zig | |
| parent | d565c5dfcdcd6753ed0d00a7f6cccdc87d2b99a2 (diff) | |
| download | zig-a4508ad7167513d178fd237e4cd361185800d05d.tar.gz zig-a4508ad7167513d178fd237e4cd361185800d05d.zip | |
fix(math): eval isPowerOfTwo at comptime in rotl/rotr
Diffstat (limited to 'lib/std/math.zig')
| -rw-r--r-- | lib/std/math.zig | 14 |
1 files changed, 8 insertions, 6 deletions
diff --git a/lib/std/math.zig b/lib/std/math.zig index f0403edd01..e7ce7c2e5e 100644 --- a/lib/std/math.zig +++ b/lib/std/math.zig @@ -682,15 +682,15 @@ pub fn rotr(comptime T: type, x: T, r: anytype) T { if (@typeInfo(C).Int.signedness == .signed) { @compileError("cannot rotate signed integers"); } - const ar = @as(Log2Int(C), @intCast(@mod(r, @typeInfo(C).Int.bits))); + const ar: Log2Int(C) = @intCast(@mod(r, @typeInfo(C).Int.bits)); return (x >> @splat(ar)) | (x << @splat(1 + ~ar)); } else if (@typeInfo(T).Int.signedness == .signed) { @compileError("cannot rotate signed integer"); } else { if (T == u0) return 0; - if (isPowerOfTwo(@typeInfo(T).Int.bits)) { - const ar = @as(Log2Int(T), @intCast(@mod(r, @typeInfo(T).Int.bits))); + if (comptime isPowerOfTwo(@typeInfo(T).Int.bits)) { + const ar: Log2Int(T) = @intCast(@mod(r, @typeInfo(T).Int.bits)); return x >> ar | x << (1 +% ~ar); } else { const ar = @mod(r, @typeInfo(T).Int.bits); @@ -713,6 +713,7 @@ test "rotr" { try testing.expect(rotr(u8, 0b00000001, @as(usize, 8)) == 0b00000001); try testing.expect(rotr(u8, 0b00000001, @as(usize, 4)) == 0b00010000); try testing.expect(rotr(u8, 0b00000001, @as(isize, -1)) == 0b00000010); + try testing.expect(rotr(u12, 0o7777, 1) == 0o7777); try testing.expect(rotr(@Vector(1, u32), @Vector(1, u32){1}, @as(usize, 1))[0] == @as(u32, 1) << 31); try testing.expect(rotr(@Vector(1, u32), @Vector(1, u32){1}, @as(isize, -1))[0] == @as(u32, 1) << 1); } @@ -727,15 +728,15 @@ pub fn rotl(comptime T: type, x: T, r: anytype) T { if (@typeInfo(C).Int.signedness == .signed) { @compileError("cannot rotate signed integers"); } - const ar = @as(Log2Int(C), @intCast(@mod(r, @typeInfo(C).Int.bits))); + const ar: Log2Int(C) = @intCast(@mod(r, @typeInfo(C).Int.bits)); return (x << @splat(ar)) | (x >> @splat(1 +% ~ar)); } else if (@typeInfo(T).Int.signedness == .signed) { @compileError("cannot rotate signed integer"); } else { if (T == u0) return 0; - if (isPowerOfTwo(@typeInfo(T).Int.bits)) { - const ar = @as(Log2Int(T), @intCast(@mod(r, @typeInfo(T).Int.bits))); + if (comptime isPowerOfTwo(@typeInfo(T).Int.bits)) { + const ar: Log2Int(T) = @intCast(@mod(r, @typeInfo(T).Int.bits)); return x << ar | x >> 1 +% ~ar; } else { const ar = @mod(r, @typeInfo(T).Int.bits); @@ -758,6 +759,7 @@ test "rotl" { try testing.expect(rotl(u8, 0b00000001, @as(usize, 8)) == 0b00000001); try testing.expect(rotl(u8, 0b00000001, @as(usize, 4)) == 0b00010000); try testing.expect(rotl(u8, 0b00000001, @as(isize, -1)) == 0b10000000); + try testing.expect(rotl(u12, 0o7777, 1) == 0o7777); try testing.expect(rotl(@Vector(1, u32), @Vector(1, u32){1 << 31}, @as(usize, 1))[0] == 1); try testing.expect(rotl(@Vector(1, u32), @Vector(1, u32){1 << 31}, @as(isize, -1))[0] == @as(u32, 1) << 30); } |