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Diffstat (limited to 'sysdeps/ia64/fpu/s_modff.S')
| -rw-r--r-- | sysdeps/ia64/fpu/s_modff.S | 278 |
1 files changed, 278 insertions, 0 deletions
diff --git a/sysdeps/ia64/fpu/s_modff.S b/sysdeps/ia64/fpu/s_modff.S new file mode 100644 index 0000000000..36e02be81b --- /dev/null +++ b/sysdeps/ia64/fpu/s_modff.S @@ -0,0 +1,278 @@ +.file "modff.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 +//============================================================== +// float modff(float x, float *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 0x10016 +// -----------------------+-----------------+------------- +// SMALL | NORMAL | HUGE +// p11 --------------->|<----- p12 ----->| <-------------- p9 +// p10 --------------------------------->| +// p13 --------------------------------------------------->| +// + +// floating-point registers used: +MODF_NORM_F8 = f9 +MODF_FRACTION_PART = f10 +MODF_INTEGER_PART = f11 +MODF_INT_INTEGER_PART = f12 + + +// general registers used +modf_signexp = r14 +modf_GR_no_frac = r15 +modf_GR_FFFF = r16 +modf_17_ones = r17 +modf_exp = r18 +// r33 = iptr + + +.section .text +GLOBAL_LIBM_ENTRY(modff) + +// 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 = 0x10016, 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.s.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.s.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) stfs [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) stfs [r33] = MODF_NORM_F8 +(p7) fmerge.s f8 = MODF_NORM_F8, MODF_NORM_F8 + nop.i 999 ;; +} + +{ .mmi +(p9) stfs [r33] = MODF_INTEGER_PART + nop.m 999 + nop.i 999 ;; +} + +// For NORMAL compute fraction part +{ .mfi +(p11) stfs [r33] = MODF_INTEGER_PART +(p12) fms.s.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) stfs [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(modff) |