// SPDX-License-Identifier: GPL-2.0-only /* IEEE754 floating point arithmetic * double precision: common utilities */ /* * MIPS floating point support * Copyright (C) 1994-2000 Algorithmics Ltd. * Copyright (C) 2017 Imagination Technologies, Ltd. * Author: Aleksandar Markovic <aleksandar.markovic@imgtec.com> */ #include "ieee754dp.h" union ieee754dp ieee754dp_rint(union ieee754dp x) { union ieee754dp ret; u64 residue; int sticky; int round; int odd; COMPXDP; ieee754_clearcx(); EXPLODEXDP; FLUSHXDP; if (xc == IEEE754_CLASS_SNAN) return ieee754dp_nanxcpt(x); if ((xc == IEEE754_CLASS_QNAN) || (xc == IEEE754_CLASS_INF) || (xc == IEEE754_CLASS_ZERO)) return x; if (xe >= DP_FBITS) return x; if (xe < -1) { residue = xm; round = 0; sticky = residue != 0; xm = 0; } else { residue = xm << (64 - DP_FBITS + xe); round = (residue >> 63) != 0; sticky = (residue << 1) != 0; xm >>= DP_FBITS - xe; } odd = (xm & 0x1) != 0x0; switch (ieee754_csr.rm) { case FPU_CSR_RN: /* toward nearest */ if (round && (sticky || odd)) xm++; break; case FPU_CSR_RZ: /* toward zero */ break; case FPU_CSR_RU: /* toward +infinity */ if ((round || sticky) && !xs) xm++; break; case FPU_CSR_RD: /* toward -infinity */ if ((round || sticky) && xs) xm++; break; } if (round || sticky) ieee754_setcx(IEEE754_INEXACT); ret = ieee754dp_flong(xm); DPSIGN(ret) = xs; return ret; }