/* * Copyright (c) 2002 Apple Computer, Inc. All rights reserved. * * @APPLE_LICENSE_HEADER_START@ * * The contents of this file constitute Original Code as defined in and * are subject to the Apple Public Source License Version 1.1 (the * "License"). You may not use this file except in compliance with the * License. Please obtain a copy of the License at * http://www.apple.com/publicsource and read it before using this file. * * This Original Code and all software distributed under the License are * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the * License for the specific language governing rights and limitations * under the License. * * @APPLE_LICENSE_HEADER_END@ */ /******************************************************************************* * * * File copysign.c, * * Function copysign for PowerPC based machines. * * * * Copyright © 1991-2001 Apple Computer, Inc. All rights reserved. * * * * Written by A. Sazegari, started on June 1991. * * Modified and ported by Robert A. Murley (ram) for Mac OS X. * * * * A MathLib v4 file. * * * * August 26 1991: no CFront Version 1.1d17 warnings. * * September 06 1991: passes the test suite with invalid raised on * * signaling nans. sane rom code behaves the same. * * September 24 1992: took the ̉#include support.hÓ out. * * Dcember 02 1992: PowerPC port. * * July 20 1994: __FABS added * * July 21 1994: deleted unnecessary functions: neg, COPYSIGNnew, * * and SIGNNUMnew. * * April 11 2001: first port to os x using gcc. * * removed fabs and deffered to gcc for direct * * instruction generation. * * August 28 2001: replaced DblInHex typedef with hexdouble. * * added #ifdef __ppc__. * * September 09 2001: added more comments. * * September 10 2001: added macros to detect PowerPC and correct compiler. * * October 08 2001: removed <CoreServices/CoreServices.h>. * * changed compiler errors to warnings. * * November 06 2001: commented out warning about Intel architectures. * * * * W A R N I N G: * * These routines require a 64-bit double precision IEEE-754 model. * * They are written for PowerPC only and are expecting the compiler * * to generate the correct sequence of multiply-add fused instructions. * * * * These routines are not intended for 32-bit Intel architectures. * * * * A version of gcc higher than 932 is required. * * * * GCC compiler options: * * optimization level 3 (-O3) * * -fschedule-insns -finline-functions -funroll-all-loops * * * *******************************************************************************/ #include "fp_private.h" /******************************************************************************* * Function copysign. * * Produces a value with the magnitude of its first argument and sign of * * its second argument. NOTE: the order of the arguments matches the * * recommendation of the IEEE-754 floating-point standard, which is the * * opposite from SANE's copysign function. * *******************************************************************************/ static inline double __copysign_MEM ( double x, double y ) { hexdouble hx, hy; register uint32_t GPR_7f, GPR_80, GPR_x, GPR_y; register double result; /******************************************************************************* * No need to flush NaNs out. * *******************************************************************************/ hx.d = x; hy.d = y; GPR_7f = 0x7fffffff; GPR_80 = 0x80000000; __NOOP; __NOOP; __NOOP; // gaurantees next instruction is in different issue group, so allows store-fwd. GPR_x = hx.i.hi; GPR_x &= GPR_7f; GPR_y = hy.i.hi; GPR_x |= GPR_y & GPR_80; hx.i.hi = GPR_x; __NOOP; __NOOP; __NOOP; result = hx.d; return result; } double copysign ( double x, double y ) { double pos_x, neg_x; double pos_y, neg_y, t; pos_x = __fabs(x); neg_x = __fnabs(x); pos_y = __fabs(y); neg_y = __fnabs(y); if (unlikely(pos_y == neg_y)) return __copysign_MEM(x, y); if (unlikely(y != y)) return __copysign_MEM(x, y); t = __fsel(y, pos_x, neg_x); return t; } static inline float __copysignf_MEM ( float x, float y ) { hexsingle hx, hy; register uint32_t GPR_7f, GPR_80, GPR_x, GPR_y; register float result; /******************************************************************************* * No need to flush NaNs out. * *******************************************************************************/ hx.fval = x; hy.fval = y; GPR_7f = 0x7fffffff; GPR_80 = 0x80000000; __NOOP; __NOOP; __NOOP; // gaurantees next instruction is in different issue group, so allows store-fwd. GPR_x = hx.lval; GPR_x &= GPR_7f; GPR_y = hy.lval; GPR_x |= GPR_y & GPR_80; hx.lval = GPR_x; __NOOP; __NOOP; __NOOP; result = hx.fval; return result; } float copysignf ( float x, float y ) { double pos_x, neg_x; double pos_y, neg_y; float t; pos_x = __fabs(x); neg_x = __fnabs(x); pos_y = __fabs(y); neg_y = __fnabs(y); if (unlikely(pos_y == neg_y)) return __copysignf_MEM(x, y); if (unlikely(y != y)) return __copysignf_MEM(x, y); t = __fsels(y, pos_x, neg_x); return t; }