| /* ===-- floatundixf.c - Implement __floatundixf ---------------------------=== |
| * |
| * 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 __floatundixf for the compiler_rt library. |
| * |
| * ===----------------------------------------------------------------------=== |
| */ |
| |
| #if !_ARCH_PPC |
| |
| #include "int_lib.h" |
| |
| /* Returns: convert a to a long double, rounding toward even. */ |
| |
| /* Assumption: long double is a IEEE 80 bit floating point type padded to 128 bits |
| * du_int is a 64 bit integral type |
| */ |
| |
| /* gggg gggg gggg gggg gggg gggg gggg gggg | gggg gggg gggg gggg seee eeee eeee eeee | |
| * 1mmm mmmm mmmm mmmm mmmm mmmm mmmm mmmm | mmmm mmmm mmmm mmmm mmmm mmmm mmmm mmmm |
| */ |
| COMPILER_RT_ABI long double |
| __floatundixf(du_int a) |
| { |
| if (a == 0) |
| return 0.0; |
| const unsigned N = sizeof(du_int) * CHAR_BIT; |
| int clz = __builtin_clzll(a); |
| int e = (N - 1) - clz ; /* exponent */ |
| long_double_bits fb; |
| fb.u.high.s.low = (e + 16383); /* exponent */ |
| fb.u.low.all = a << clz; /* mantissa */ |
| return fb.f; |
| } |
| |
| #endif /* _ARCH_PPC */ |
