/* clang-format off */ /* ===-- floatdixf.c - Implement __floatdixf -------------------------------=== * * 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 __floatdixf for the compiler_rt library. * * ===----------------------------------------------------------------------=== */ STATIC_YOINK("huge_compiler_rt_license"); #if !_ARCH_PPC #include "third_party/compiler_rt/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 * di_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 __floatdixf(di_int a) { if (a == 0) return 0.0; const unsigned N = sizeof(di_int) * CHAR_BIT; const di_int s = a >> (N-1); a = (a ^ s) - s; int clz = __builtin_clzll(a); int e = (N - 1) - clz ; /* exponent */ long_double_bits fb; fb.u.high.s.low = ((su_int)s & 0x00008000) | /* sign */ (e + 16383); /* exponent */ fb.u.low.all = a << clz; /* mantissa */ return fb.f; } #endif /* !_ARCH_PPC */