.file "modf.s"// Copyright (c) 2000 - 2003, Intel Corporation// All rights reserved.//// Contributed 2000 by the Intel Numerics Group, Intel Corporation//// Redistribution and use in source and binary forms, with or without// modification, are permitted provided that the following conditions are// met://// * Redistributions of source code must retain the above copyright// notice, this list of conditions and the following disclaimer.//// * Redistributions in binary form must reproduce the above copyright// notice, this list of conditions and the following disclaimer in the// documentation and/or other materials provided with the distribution.//// * The name of Intel Corporation may not be used to endorse or promote// products derived from this software without specific prior written// permission.// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL INTEL OR ITS // CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,// EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, // PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR // PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY // OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY OR TORT (INCLUDING// NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS // SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. // // Intel Corporation is the author of this code, and requests that all// problem reports or change requests be submitted to it directly at // http://www.intel.com/software/products/opensource/libraries/num.htm.//// History//==============================================================// 02/02/00 Initial version// 04/04/00 Improved speed, corrected result for NaN input// 12/22/00 Fixed so inexact flag is never set, and invalid is not set for //            qnans nor for inputs larger than 2^63.// 05/20/02 Cleaned up namespace and sf0 syntax// 02/10/03 Reordered header: .section, .global, .proc, .align//// API//==============================================================// double modf(double x, double *iptr)// break a floating point x number into fraction and an exponent//// input  floating point f8, address in r33// output floating point f8 (x fraction), and *iptr (x integral part)//// OVERVIEW//==============================================================//// NO FRACTIONAL PART: HUGE// If// for double-extended// If the true exponent is greater than or equal 63//      1003e ==> 1003e -ffff = 3f = 63(dec)// for double// If the true exponent is greater than or equal 52//                10033 -ffff = 34 = 52(dec)// for single// If the true exponent is greater than or equal 23//                10016 -ffff = 17 = 23(dec)// then// we are already an integer (p9 true)// NO INTEGER PART:    SMALL//     Is f8 exponent less than register bias (that is, is it//     less than 1). If it is, get the right sign of//     zero and store this in iptr.// CALCULATION: NOT HUGE, NOT SMALL// To get the integer part// Take the floating-point  input and truncate //   then convert  this integer to fp  Call it  MODF_INTEGER_PART// Subtract  MODF_INTEGER_PART from MODF_NORM_F8 to get fraction part// Then put fraction part in f8 //      put integer  part MODF_INTEGER_PART into *iptr// Registers used//==============================================================// predicate registers used: // p6 - p13//                      0xFFFF           0x10033// -----------------------+-----------------+-------------//              SMALL     |      NORMAL     | HUGE//    p11 --------------->|<----- p12 ----->| <-------------- p9//    p10 --------------------------------->|//    p13 --------------------------------------------------->|//// floating-point registers used: MODF_NORM_F8               = f9MODF_FRACTION_PART         = f10MODF_INTEGER_PART          = f11MODF_INT_INTEGER_PART      = f12// general registers used modf_signexp    = r14modf_GR_no_frac = r15modf_GR_FFFF    = r16modf_17_ones    = r17 modf_exp        = r18// r33 = iptr     .section .textGLOBAL_LIBM_ENTRY(modf)// Main path is p9, p11, p8 FALSE and p12 TRUE// Assume input is normalized and get signexp// Normalize input just in case// Form exponent bias { .mfi      getf.exp  modf_signexp = f8      fnorm.s0          MODF_NORM_F8  = f8      addl           modf_GR_FFFF  = 0xffff, r0}// Get integer part of input// Form exponent mask{ .mfi      nop.m 999      fcvt.fx.trunc.s1  MODF_INT_INTEGER_PART   = f8      mov  modf_17_ones     = 0x1ffff ;;}// Is x nan or inf?// qnan snan inf norm     unorm 0 -+// 1    1    1   0        0     0 11 = 0xe3 NAN_INF// Form biased exponent where input only has an integer part{ .mfi      nop.m 999      fclass.m.unc p6,p13 = f8, 0xe3      addl modf_GR_no_frac = 0x10033, r0 ;;}// Mask to get exponent// Is x unnorm?// qnan snan inf norm     unorm 0 -+// 0    0    0   0        1     0 11 = 0x0b UNORM// Set p13 to indicate calculation path, else p6 if nan or inf { .mfi      and       modf_exp = modf_17_ones, modf_signexp       fclass.m.unc p8,p0 = f8, 0x0b      nop.i 999 ;;}// p11 <== SMALL, no integer part, fraction is everyting// p9  <== HUGE,  no fraction part, integer is everything// p12 <== NORMAL, fraction part and integer part{ .mii(p13) cmp.lt.unc p11,p10 = modf_exp, modf_GR_FFFF      nop.i 999      nop.i 999 ;;}// Is x inf? p6 if inf, p7 if nan{ .mfb(p10) cmp.ge.unc p9,p12  = modf_exp, modf_GR_no_frac(p6)  fclass.m.unc p6,p7 = f8, 0x23(p8)  br.cond.spnt MODF_DENORM ;;}MODF_COMMON:// For HUGE set fraction to signed 0{ .mfi      nop.m 999(p9)  fmerge.s f8 = f8,f0      nop.i 999}// For HUGE set integer part to normalized input{ .mfi      nop.m 999(p9)  fnorm.d.s0 MODF_INTEGER_PART = MODF_NORM_F8      nop.i 999 ;;}// For SMALL set fraction to normalized input, integer part to signed 0{ .mfi      nop.m 999(p11) fmerge.s MODF_INTEGER_PART = f8,f0      nop.i 999}{ .mfi      nop.m 999(p11) fnorm.d.s0 f8 = MODF_NORM_F8      nop.i 999 ;;}// For NORMAL float the integer part{ .mfi      nop.m 999(p12) fcvt.xf    MODF_INTEGER_PART = MODF_INT_INTEGER_PART      nop.i 999 ;;}// If x inf set integer part to INF, fraction to signed 0{ .mfi(p6)  stfd [r33] = MODF_NORM_F8(p6)  fmerge.s  f8 = f8,f0      nop.i 999 ;;}// If x nan set integer and fraction parts to NaN (quietized){ .mfi(p7)  stfd [r33] = MODF_NORM_F8(p7)  fmerge.s  f8 = MODF_NORM_F8, MODF_NORM_F8      nop.i 999 ;;}{ .mmi(p9)  stfd [r33] = MODF_INTEGER_PART      nop.m 999      nop.i 999 ;;}// For NORMAL compute fraction part{ .mfi(p11) stfd [r33] = MODF_INTEGER_PART(p12) fms.d.s0   f8 = MODF_NORM_F8,f1, MODF_INTEGER_PART      nop.i 999 ;;}// For NORMAL test if fraction part is zero; if so append correct sign{ .mfi      nop.m 999(p12) fcmp.eq.unc.s0 p7,p0 = MODF_NORM_F8, MODF_INTEGER_PART      nop.i 999 ;;}{ .mfi(p12) stfd [r33] = MODF_INTEGER_PART      nop.f 999      nop.i 999 ;;}// For NORMAL if fraction part is zero append sign of input{ .mfb      nop.m 999(p7)  fmerge.s f8 = MODF_NORM_F8, f0      br.ret.sptk    b0 ;;}MODF_DENORM:// If x unorm get signexp from normalized input// If x unorm get integer part from normalized input{ .mfi      getf.exp  modf_signexp = MODF_NORM_F8      fcvt.fx.trunc.s1  MODF_INT_INTEGER_PART   = MODF_NORM_F8      nop.i 999 ;;}// If x unorm mask to get exponent{ .mmi      and       modf_exp = modf_17_ones, modf_signexp ;;      cmp.lt.unc p11,p10 = modf_exp, modf_GR_FFFF      nop.i 999 ;;}{ .mfb(p10) cmp.ge.unc p9,p12  = modf_exp, modf_GR_no_frac      nop.f 999      br.cond.spnt MODF_COMMON ;;}GLOBAL_LIBM_END(modf)