Nixyri/zig
1
0
Fork 0
mirror of https://github.com/ziglang/zig.git synced 2024-11-15 00:26:57 +00:00
Code Issues Packages Projects Releases Wiki Activity

Fix overflow in std.math.isNormal when applied to -Inf or a negative NaN

Browse Source
This commit is contained in:
Jonathan S 2022-01-29 10:11:49 -06:00 committed by GitHub
parent ba445013c4
commit aca665cebd
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
1 changed files with 16 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

20
lib/std/math/isnormal.zig
View File

@ -9,19 +9,19 @@ pub fn isNormal(x: anytype) bool {
switch (T) {
f16 => {
const bits = @bitCast(u16, x);
return (bits + (1 << 10)) & (maxInt(u16) >> 1) >= (1 << 11);
return (bits +% (1 << 10)) & (maxInt(u16) >> 1) >= (1 << 11);
},
f32 => {
const bits = @bitCast(u32, x);
return (bits + (1 << 23)) & (maxInt(u32) >> 1) >= (1 << 24);
return (bits +% (1 << 23)) & (maxInt(u32) >> 1) >= (1 << 24);
},
f64 => {
const bits = @bitCast(u64, x);
return (bits + (1 << 52)) & (maxInt(u64) >> 1) >= (1 << 53);
return (bits +% (1 << 52)) & (maxInt(u64) >> 1) >= (1 << 53);
},
f128 => {
const bits = @bitCast(u128, x);
return (bits + (1 << 112)) & (maxInt(u128) >> 1) >= (1 << 113);
return (bits +% (1 << 112)) & (maxInt(u128) >> 1) >= (1 << 113);
},
else => {
@compileError("isNormal not implemented for " ++ @typeName(T));
@ -34,6 +34,18 @@ test "math.isNormal" {
try expect(!isNormal(math.nan(f32)));
try expect(!isNormal(math.nan(f64)));
try expect(!isNormal(math.nan(f128)));
try expect(!isNormal(-math.nan(f16)));
try expect(!isNormal(-math.nan(f32)));
try expect(!isNormal(-math.nan(f64)));
try expect(!isNormal(-math.nan(f128)));
try expect(!isNormal(math.inf(f16)));
try expect(!isNormal(math.inf(f32)));
try expect(!isNormal(math.inf(f64)));
try expect(!isNormal(math.inf(f128)));
try expect(!isNormal(-math.inf(f16)));
try expect(!isNormal(-math.inf(f32)));
try expect(!isNormal(-math.inf(f64)));
try expect(!isNormal(-math.inf(f128)));
try expect(!isNormal(@as(f16, 0)));
try expect(!isNormal(@as(f32, 0)));
try expect(!isNormal(@as(f64, 0)));