diff options
Diffstat (limited to 'lib/builtins/fixunsdfsi.c')
| -rw-r--r-- | lib/builtins/fixunsdfsi.c | 44 | 
1 files changed, 44 insertions, 0 deletions
| diff --git a/lib/builtins/fixunsdfsi.c b/lib/builtins/fixunsdfsi.c new file mode 100644 index 000000000000..c6a3c755e90f --- /dev/null +++ b/lib/builtins/fixunsdfsi.c @@ -0,0 +1,44 @@ +/* ===-- fixunsdfsi.c - Implement __fixunsdfsi -----------------------------=== + * + *                     The LLVM Compiler Infrastructure + * + * This file is dual licensed under the MIT and the University of Illinois Open + * Source Licenses. See LICENSE.TXT for details. + * + * ===----------------------------------------------------------------------=== + * + * This file implements __fixunsdfsi for the compiler_rt library. + * + * ===----------------------------------------------------------------------=== + */ + +#include "int_lib.h" + +/* Returns: convert a to a unsigned int, rounding toward zero. + *          Negative values all become zero. + */ + +/* Assumption: double is a IEEE 64 bit floating point type  + *             su_int is a 32 bit integral type + *             value in double is representable in su_int or is negative  + *                 (no range checking performed) + */ + +/* seee eeee eeee mmmm mmmm mmmm mmmm mmmm | mmmm mmmm mmmm mmmm mmmm mmmm mmmm mmmm */ + +ARM_EABI_FNALIAS(d2uiz, fixunsdfsi) + +COMPILER_RT_ABI su_int +__fixunsdfsi(double a) +{ +    double_bits fb; +    fb.f = a; +    int e = ((fb.u.s.high & 0x7FF00000) >> 20) - 1023; +    if (e < 0 || (fb.u.s.high & 0x80000000)) +        return 0; +    return ( +                0x80000000u                      | +                ((fb.u.s.high & 0x000FFFFF) << 11) | +                (fb.u.s.low >> 21) +           ) >> (31 - e); +} | 
