Index: lib/fixtfsi.c =================================================================== --- /dev/null +++ lib/fixtfsi.c @@ -0,0 +1,47 @@ +//===-- lib/fixtfsi.c - Quad-precision -> integer conversion ------*- C -*-===// +// +// 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 quad-precision to integer conversion for the +// compiler-rt library. No range checking is performed; the behavior of this +// conversion is undefined for out of range values in the C standard. +// +//===----------------------------------------------------------------------===// + +#define QUAD_PRECISION +#include "fp_lib.h" + +#include "int_lib.h" + +int __fixtfsi(fp_t a) { + + // Break a into sign, exponent, significand + const rep_t aRep = toRep(a); + const rep_t aAbs = aRep & absMask; + const int sign = aRep & signBit ? -1 : 1; + const int exponent = (aAbs >> significandBits) - exponentBias; + const rep_t significand = (aAbs & significandMask) | implicitBit; + + // If 0 < exponent < significandBits, right shift to get the result. + if ((unsigned int)exponent < significandBits) { + return sign * (significand >> (significandBits - exponent)); + } + + // If exponent is negative, the result is zero. + else if (exponent < 0) { + return 0; + } + + // If significandBits < exponent, left shift to get the result. This shift + // may end up being larger than the type width, which incurs undefined + // behavior, but the conversion itself is undefined in that case, so + // whatever the compiler decides to do is fine. + else { + return sign * (significand << (exponent - significandBits)); + } +} Index: lib/fixunstfsi.c =================================================================== --- /dev/null +++ lib/fixunstfsi.c @@ -0,0 +1,43 @@ +/* ===-- fixunstfsi.c - Implement __fixunstfsi -----------------------------=== + * + * 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 __fixunstfsi 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: long double is a IEEE 128 bit floating point type + * su_int is a 32 bit integral type + * value in long double is representable in su_int or is negative + * (no range checking performed) + */ + +/* seee eeee eeee eeee mmmm mmmm mmmm mmmm | mmmm mmmm mmmm mmmm mmmm mmmm mmmm mmmm + mmmm mmmm mmmm mmmm mmmm mmmm mmmm mmmm | mmmm mmmm mmmm mmmm mmmm mmmm mmmm mmmm */ + +COMPILER_RT_ABI su_int +__fixunstfsi(long double a) +{ + long_double_bits fb; + fb.f = a; + int e = ((fb.u.high.s.high & 0x7FFF0000) >> 16) - 16383; + if (e < 0 || (fb.u.high.s.high & 0x80000000)) + return 0; + return ( + 0x80000000u | + ((fb.u.high.s.high & 0x0000FFFF) << 15) | + (fb.u.high.s.low >> 17) + ) >> (31 - e); +}