1*0Sstevel@tonic-gate /* 2*0Sstevel@tonic-gate * CDDL HEADER START 3*0Sstevel@tonic-gate * 4*0Sstevel@tonic-gate * The contents of this file are subject to the terms of the 5*0Sstevel@tonic-gate * Common Development and Distribution License, Version 1.0 only 6*0Sstevel@tonic-gate * (the "License"). You may not use this file except in compliance 7*0Sstevel@tonic-gate * with the License. 8*0Sstevel@tonic-gate * 9*0Sstevel@tonic-gate * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 10*0Sstevel@tonic-gate * or http://www.opensolaris.org/os/licensing. 11*0Sstevel@tonic-gate * See the License for the specific language governing permissions 12*0Sstevel@tonic-gate * and limitations under the License. 13*0Sstevel@tonic-gate * 14*0Sstevel@tonic-gate * When distributing Covered Code, include this CDDL HEADER in each 15*0Sstevel@tonic-gate * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 16*0Sstevel@tonic-gate * If applicable, add the following below this CDDL HEADER, with the 17*0Sstevel@tonic-gate * fields enclosed by brackets "[]" replaced with your own identifying 18*0Sstevel@tonic-gate * information: Portions Copyright [yyyy] [name of copyright owner] 19*0Sstevel@tonic-gate * 20*0Sstevel@tonic-gate * CDDL HEADER END 21*0Sstevel@tonic-gate */ 22*0Sstevel@tonic-gate /* 23*0Sstevel@tonic-gate * Copyright (c) 1990, 1991 UNIX System Laboratories, Inc. 24*0Sstevel@tonic-gate * Copyright (c) 1988 AT&T 25*0Sstevel@tonic-gate * All Rights Reserved 26*0Sstevel@tonic-gate */ 27*0Sstevel@tonic-gate 28*0Sstevel@tonic-gate /* 29*0Sstevel@tonic-gate * Copyright 2004 Sun Microsystems, Inc. All rights reserved. 30*0Sstevel@tonic-gate * Use is subject to license terms. 31*0Sstevel@tonic-gate */ 32*0Sstevel@tonic-gate 33*0Sstevel@tonic-gate #pragma ident "%Z%%M% %I% %E% SMI" 34*0Sstevel@tonic-gate 35*0Sstevel@tonic-gate /* 36*0Sstevel@tonic-gate * Establish the default settings for the floating-point state for a C language 37*0Sstevel@tonic-gate * program: 38*0Sstevel@tonic-gate * rounding mode -- round to nearest default by OS, 39*0Sstevel@tonic-gate * exceptions enabled -- all masked 40*0Sstevel@tonic-gate * sticky bits -- all clear by default by OS. 41*0Sstevel@tonic-gate * precision control -- double extended 42*0Sstevel@tonic-gate * Set _fp_hw according to what floating-point hardware is available. 43*0Sstevel@tonic-gate * Set _sse_hw according to what SSE hardware is available. 44*0Sstevel@tonic-gate * Set __flt_rounds according to the rounding mode. 45*0Sstevel@tonic-gate */ 46*0Sstevel@tonic-gate 47*0Sstevel@tonic-gate #pragma weak _fpstart = __fpstart 48*0Sstevel@tonic-gate 49*0Sstevel@tonic-gate #include "synonyms.h" 50*0Sstevel@tonic-gate #include <sys/types.h> 51*0Sstevel@tonic-gate #include <sys/sysi86.h> /* for SI86FPHW/SI86FPSTART definitions */ 52*0Sstevel@tonic-gate #include <sys/fp.h> /* for FPU_CW_INIT and SSE_MXCSR_INIT */ 53*0Sstevel@tonic-gate 54*0Sstevel@tonic-gate extern int _private_sysi86(); 55*0Sstevel@tonic-gate extern int __fltrounds(); 56*0Sstevel@tonic-gate 57*0Sstevel@tonic-gate int _fp_hw; /* default: bss: 0 == no hardware */ 58*0Sstevel@tonic-gate int _sse_hw; /* default: bss: 0 == no sse */ 59*0Sstevel@tonic-gate int __flt_rounds; /* ANSI rounding mode */ 60*0Sstevel@tonic-gate 61*0Sstevel@tonic-gate void 62*0Sstevel@tonic-gate __fpstart() 63*0Sstevel@tonic-gate { 64*0Sstevel@tonic-gate /* 65*0Sstevel@tonic-gate * query OS for HW status and ensure the x87 and (optional) 66*0Sstevel@tonic-gate * SSE control words are (will be) set correctly. 67*0Sstevel@tonic-gate */ 68*0Sstevel@tonic-gate if ((_sse_hw = _private_sysi86(SI86FPSTART, 69*0Sstevel@tonic-gate &_fp_hw, FPU_CW_INIT, SSE_MXCSR_INIT)) == -1) { 70*0Sstevel@tonic-gate extern void _putcw(); 71*0Sstevel@tonic-gate 72*0Sstevel@tonic-gate /* 73*0Sstevel@tonic-gate * (fallback to old syscall on old kernels) 74*0Sstevel@tonic-gate */ 75*0Sstevel@tonic-gate _sse_hw = 0; 76*0Sstevel@tonic-gate (void) _private_sysi86(SI86FPHW, &_fp_hw); 77*0Sstevel@tonic-gate _putcw(0x133f); 78*0Sstevel@tonic-gate } 79*0Sstevel@tonic-gate 80*0Sstevel@tonic-gate /* 81*0Sstevel@tonic-gate * At this point the x87 fp environment that has been (or more 82*0Sstevel@tonic-gate * hopefully, will be) established by the kernel is: 83*0Sstevel@tonic-gate * 84*0Sstevel@tonic-gate * affine infinity 0x1000 85*0Sstevel@tonic-gate * round to nearest 0x0000 86*0Sstevel@tonic-gate * 64-bit doubles 0x0300 87*0Sstevel@tonic-gate * precision, underflow, overflow, zero-divide, denorm, invalid masked 88*0Sstevel@tonic-gate * 0x003f 89*0Sstevel@tonic-gate * 90*0Sstevel@tonic-gate * which conforms to the 4th edition i386 ABI definition. 91*0Sstevel@tonic-gate * 92*0Sstevel@tonic-gate * Additionally, if we have SSE hardware, we've also masked all 93*0Sstevel@tonic-gate * the same traps, and have round to nearest. 94*0Sstevel@tonic-gate */ 95*0Sstevel@tonic-gate 96*0Sstevel@tonic-gate __flt_rounds = 1; /* ANSI way of saying round-to-nearest */ 97*0Sstevel@tonic-gate } 98