| /* ===-- fixunsdfti.c - Implement __fixunsdfti -----------------------------=== |
| * |
| * 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 __fixunsdfti for the compiler_rt library. |
| * |
| * ===----------------------------------------------------------------------=== |
| */ |
| |
| #include "int_lib.h" |
| |
| #if __x86_64 |
| |
| /* Returns: convert a to a unsigned long long, rounding toward zero. |
| * Negative values all become zero. |
| */ |
| |
| /* Assumption: double is a IEEE 64 bit floating point type |
| * tu_int is a 64 bit integral type |
| * value in double is representable in tu_int or is negative |
| * (no range checking performed) |
| */ |
| |
| /* seee eeee eeee mmmm mmmm mmmm mmmm mmmm | mmmm mmmm mmmm mmmm mmmm mmmm mmmm mmmm */ |
| |
| tu_int |
| __fixunsdfti(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; |
| tu_int r = 0x0010000000000000uLL | (fb.u.all & 0x000FFFFFFFFFFFFFuLL); |
| if (e > 52) |
| r <<= (e - 52); |
| else |
| r >>= (52 - e); |
| return r; |
| } |
| |
| #endif |