     1
     2
     3
     4
     5
     6
     7
     8
     9
    10
    11
    12
    13
    14
    15
    16
    17
    18
    19
    20
    21
    22
    23
    24
    25
    26
    27
    28
    29
    30
    31

    const FP_ILOGBNAN: i32 = -1 - 0x7fffffff;
    const FP_ILOGB0: i32 = FP_ILOGBNAN;

    pub fn ilogb(x: f64) -> i32 {
        let mut i: u64 = x.to_bits();
        let e = ((i >> 52) & 0x7ff) as i32;

        if e == 0 {
            i <<= 12;
            if i == 0 {
                force_eval!(0.0 / 0.0);
                return FP_ILOGB0;
            }
            /* subnormal x */
            let mut e = -0x3ff;
            while (i >> 63) == 0 {
                e -= 1;
                i <<= 1;
            }
            e
        } else if e == 0x7ff {
            force_eval!(0.0 / 0.0);
            if (i << 12) != 0 {
                FP_ILOGBNAN
            } else {
                i32::max_value()
            }
        } else {
            e - 0x3ff
        }
    }

# Help

## Keyboard Shortcuts

`?`
  Show this help dialog
`S`
  Focus the search field
`↑`
  Move up in search results
`↓`
  Move down in search results
`↹`
  Switch tab
`⏎`
  Go to active search result
`+`
  Expand all sections
`-`
  Collapse all sections

## Search Tricks

Prefix searches with a type followed by a colon (e.g., `fn:`) to restrict the search to a given type.

Accepted types are: `fn`, `mod`, `struct`, `enum`, `trait`, `type`, `macro`, and `const`.

Search functions by type signature (e.g., `vec -> usize` or `* -> vec`)

Search multiple things at once by splitting your query with comma (e.g., `str,u8` or `String,struct:Vec,test`)