X-Git-Url: https://oss.titaniummirror.com/gitweb?a=blobdiff_plain;f=libgcc%2Fconfig%2Flibbid%2Fbid128_scalb.c;fp=libgcc%2Fconfig%2Flibbid%2Fbid128_scalb.c;h=589713476e1daeb986fd9f24ee254d7145fa2bf9;hb=6fed43773c9b0ce596dca5686f37ac3fc0fa11c0;hp=0000000000000000000000000000000000000000;hpb=27b11d56b743098deb193d510b337ba22dc52e5c;p=msp430-gcc.git diff --git a/libgcc/config/libbid/bid128_scalb.c b/libgcc/config/libbid/bid128_scalb.c new file mode 100644 index 00000000..58971347 --- /dev/null +++ b/libgcc/config/libbid/bid128_scalb.c @@ -0,0 +1,96 @@ +/* Copyright (C) 2007, 2009 Free Software Foundation, Inc. + +This file is part of GCC. + +GCC is free software; you can redistribute it and/or modify it under +the terms of the GNU General Public License as published by the Free +Software Foundation; either version 3, or (at your option) any later +version. + +GCC is distributed in the hope that it will be useful, but WITHOUT ANY +WARRANTY; without even the implied warranty of MERCHANTABILITY or +FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License +for more details. + +Under Section 7 of GPL version 3, you are granted additional +permissions described in the GCC Runtime Library Exception, version +3.1, as published by the Free Software Foundation. + +You should have received a copy of the GNU General Public License and +a copy of the GCC Runtime Library Exception along with this program; +see the files COPYING3 and COPYING.RUNTIME respectively. If not, see +. */ + +#define BID_128RES +#include "bid_internal.h" + +#define DECIMAL_EXPONENT_BIAS_128 6176 +#define MAX_DECIMAL_EXPONENT_128 12287 + + + +BID128_FUNCTION_ARG128_ARGTYPE2 (bid128_scalb, x, int, n) + + UINT128 CX, CX2, CX8, res; + SINT64 exp64; + UINT64 sign_x; + int exponent_x, rmode; + + // unpack arguments, check for NaN or Infinity +if (!unpack_BID128_value (&sign_x, &exponent_x, &CX, x)) { + // x is Inf. or NaN or 0 +#ifdef SET_STATUS_FLAGS +if ((x.w[1] & SNAN_MASK64) == SNAN_MASK64) // y is sNaN + __set_status_flags (pfpsf, INVALID_EXCEPTION); +#endif +res.w[1] = CX.w[1] & QUIET_MASK64; +res.w[0] = CX.w[0]; +if (!CX.w[1]) { + exp64 = (SINT64) exponent_x + (SINT64) n; + if(exp64<0) exp64=0; + if(exp64>MAX_DECIMAL_EXPONENT_128) exp64=MAX_DECIMAL_EXPONENT_128; + exponent_x = exp64; + get_BID128_very_fast (&res, sign_x, exponent_x, CX); +} +BID_RETURN (res); +} + +exp64 = (SINT64) exponent_x + (SINT64) n; +exponent_x = exp64; + +if ((UINT32) exponent_x <= MAX_DECIMAL_EXPONENT_128) { + get_BID128_very_fast (&res, sign_x, exponent_x, CX); + BID_RETURN (res); +} + // check for overflow +if (exp64 > MAX_DECIMAL_EXPONENT_128) { + if (CX.w[1] < 0x314dc6448d93ull) { + // try to normalize coefficient + do { + CX8.w[1] = (CX.w[1] << 3) | (CX.w[0] >> 61); + CX8.w[0] = CX.w[0] << 3; + CX2.w[1] = (CX.w[1] << 1) | (CX.w[0] >> 63); + CX2.w[0] = CX.w[0] << 1; + __add_128_128 (CX, CX2, CX8); + + exponent_x--; + exp64--; + } + while (CX.w[1] < 0x314dc6448d93ull + && exp64 > MAX_DECIMAL_EXPONENT_128); + + } + if (exp64 <= MAX_DECIMAL_EXPONENT_128) { + get_BID128_very_fast (&res, sign_x, exponent_x, CX); + BID_RETURN (res); + } else + exponent_x = 0x7fffffff; // overflow +} + // exponent < 0 + // the BID pack routine will round the coefficient +rmode = rnd_mode; +get_BID128 (&res, sign_x, exponent_x, CX, (unsigned int *) &rmode, + pfpsf); +BID_RETURN (res); + +}