?? s_expm1f.s
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.file "expf_m1.s"// Copyright (c) 2000 - 2005, 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 Unwind support added// 08/15/00 Bundle added after call to __libm_error_support to properly// set [the previously overwritten] GR_Parameter_RESULT.// 07/07/01 Improved speed of all paths// 05/20/02 Cleaned up namespace and sf0 syntax// 11/20/02 Improved speed, algorithm based on expf// 03/31/05 Reformatted delimiters between data tables////// API//*********************************************************************// float expm1f(float)//// Overview of operation//*********************************************************************// 1. Inputs of Nan, Inf, Zero, NatVal handled with special paths//// 2. |x| < 2^-40// Result = x, computed by x + x*x to handle appropriate flags and rounding//// 3. 2^-40 <= |x| < 2^-2// Result determined by 8th order Taylor series polynomial// expm1f(x) = x + A2*x^2 + ... + A8*x^8//// 4. x < -24.0// Here we know result is essentially -1 + eps, where eps only affects// rounded result. Set I.//// 5. x >= 88.7228 // Result overflows. Set I, O, and call error support//// 6. 2^-2 <= x < 88.7228 or -24.0 <= x < -2^-2 // This is the main path. The algorithm is described below:// Take the input x. w is "how many log2/128 in x?"// w = x * 64/log2// NJ = int(w)// x = NJ*log2/64 + R// NJ = 64*n + j// x = n*log2 + (log2/64)*j + R//// So, exp(x) = 2^n * 2^(j/64)* exp(R)//// T = 2^n * 2^(j/64)// Construct 2^n// Get 2^(j/64) table// actually all the entries of 2^(j/64) table are stored in DP and// with exponent bits set to 0 -> multiplication on 2^n can be// performed by doing logical "or" operation with bits presenting 2^n// exp(R) = 1 + (exp(R) - 1)// P = exp(R) - 1 approximated by Taylor series of 3rd degree// P = A3*R^3 + A2*R^2 + R, A3 = 1/6, A2 = 1/2//// The final result is reconstructed as follows// expm1f(x) = T*P + (T - 1.0)// Special values//*********************************************************************// expm1f(+0) = +0.0// expm1f(-0) = -0.0// expm1f(+qnan) = +qnan// expm1f(-qnan) = -qnan// expm1f(+snan) = +qnan// expm1f(-snan) = -qnan// expm1f(-inf) = -1.0// expm1f(+inf) = +inf// Overflow and Underflow//*********************************************************************// expm1f(x) = largest single normal when// x = 88.7228 = 0x42b17217//// Underflow is handled as described in case 2 above.// Registers used//*********************************************************************// Floating Point registers used:// f8, input// f6,f7, f9 -> f15, f32 -> f45// General registers used:// r3, r20 -> r38// Predicate registers used:// p9 -> p15// Assembly macros//*********************************************************************// integer registers used// scratchrNJ = r3rExp_half = r20rSignexp_x = r21rExp_x = r22rExp_mask = r23rExp_bias = r24rTmp = r25rM1_lim = r25rGt_ln = r25rJ = r26rN = r27rTblAddr = r28rLn2Div64 = r29rRightShifter = r30r64DivLn2 = r31// stackedGR_SAVE_PFS = r32GR_SAVE_B0 = r33GR_SAVE_GP = r34GR_Parameter_X = r35GR_Parameter_Y = r36GR_Parameter_RESULT = r37GR_Parameter_TAG = r38// floating point registers usedFR_X = f10FR_Y = f1FR_RESULT = f8// scratchfRightShifter = f6f64DivLn2 = f7fNormX = f9fNint = f10fN = f11fR = f12fLn2Div64 = f13fA2 = f14fA3 = f15// stackedfP = f32fX3 = f33fT = f34fMIN_SGL_OFLOW_ARG = f35fMAX_SGL_NORM_ARG = f36fMAX_SGL_MINUS_1_ARG = f37fA4 = f38fA43 = f38fA432 = f38fRSqr = f39fA5 = f40fTmp = f41fGt_pln = f41fXsq = f41fA7 = f42fA6 = f43fA65 = f43fTm1 = f44fA8 = f45fA87 = f45fA8765 = f45fA8765432 = f45fWre_urm_f8 = f45RODATA.align 16LOCAL_OBJECT_START(_expf_table)data8 0x3efa01a01a01a01a // A8 = 1/8!data8 0x3f2a01a01a01a01a // A7 = 1/7!data8 0x3f56c16c16c16c17 // A6 = 1/6!data8 0x3f81111111111111 // A5 = 1/5!data8 0x3fa5555555555555 // A4 = 1/4!data8 0x3fc5555555555555 // A3 = 1/3!//data4 0x42b17218 // Smallest sgl arg to overflow sgl resultdata4 0x42b17217 // Largest sgl arg to give sgl result//// 2^(j/64) table, j goes from 0 to 63data8 0x0000000000000000 // 2^(0/64)data8 0x00002C9A3E778061 // 2^(1/64)data8 0x000059B0D3158574 // 2^(2/64)data8 0x0000874518759BC8 // 2^(3/64)data8 0x0000B5586CF9890F // 2^(4/64)data8 0x0000E3EC32D3D1A2 // 2^(5/64)data8 0x00011301D0125B51 // 2^(6/64)data8 0x0001429AAEA92DE0 // 2^(7/64)data8 0x000172B83C7D517B // 2^(8/64)data8 0x0001A35BEB6FCB75 // 2^(9/64)data8 0x0001D4873168B9AA // 2^(10/64)data8 0x0002063B88628CD6 // 2^(11/64)data8 0x0002387A6E756238 // 2^(12/64)data8 0x00026B4565E27CDD // 2^(13/64)data8 0x00029E9DF51FDEE1 // 2^(14/64)data8 0x0002D285A6E4030B // 2^(15/64)data8 0x000306FE0A31B715 // 2^(16/64)data8 0x00033C08B26416FF // 2^(17/64)data8 0x000371A7373AA9CB // 2^(18/64)data8 0x0003A7DB34E59FF7 // 2^(19/64)data8 0x0003DEA64C123422 // 2^(20/64)data8 0x0004160A21F72E2A // 2^(21/64)data8 0x00044E086061892D // 2^(22/64)data8 0x000486A2B5C13CD0 // 2^(23/64)data8 0x0004BFDAD5362A27 // 2^(24/64)data8 0x0004F9B2769D2CA7 // 2^(25/64)data8 0x0005342B569D4F82 // 2^(26/64)data8 0x00056F4736B527DA // 2^(27/64)data8 0x0005AB07DD485429 // 2^(28/64)data8 0x0005E76F15AD2148 // 2^(29/64)data8 0x0006247EB03A5585 // 2^(30/64)data8 0x0006623882552225 // 2^(31/64)data8 0x0006A09E667F3BCD // 2^(32/64)data8 0x0006DFB23C651A2F // 2^(33/64)data8 0x00071F75E8EC5F74 // 2^(34/64)data8 0x00075FEB564267C9 // 2^(35/64)data8 0x0007A11473EB0187 // 2^(36/64)data8 0x0007E2F336CF4E62 // 2^(37/64)data8 0x00082589994CCE13 // 2^(38/64)data8 0x000868D99B4492ED // 2^(39/64)data8 0x0008ACE5422AA0DB // 2^(40/64)data8 0x0008F1AE99157736 // 2^(41/64)data8 0x00093737B0CDC5E5 // 2^(42/64)data8 0x00097D829FDE4E50 // 2^(43/64)data8 0x0009C49182A3F090 // 2^(44/64)data8 0x000A0C667B5DE565 // 2^(45/64)data8 0x000A5503B23E255D // 2^(46/64)data8 0x000A9E6B5579FDBF // 2^(47/64)data8 0x000AE89F995AD3AD // 2^(48/64)data8 0x000B33A2B84F15FB // 2^(49/64)data8 0x000B7F76F2FB5E47 // 2^(50/64)data8 0x000BCC1E904BC1D2 // 2^(51/64)data8 0x000C199BDD85529C // 2^(52/64)data8 0x000C67F12E57D14B // 2^(53/64)data8 0x000CB720DCEF9069 // 2^(54/64)data8 0x000D072D4A07897C // 2^(55/64)data8 0x000D5818DCFBA487 // 2^(56/64)data8 0x000DA9E603DB3285 // 2^(57/64)data8 0x000DFC97337B9B5F // 2^(58/64)data8 0x000E502EE78B3FF6 // 2^(59/64)data8 0x000EA4AFA2A490DA // 2^(60/64)data8 0x000EFA1BEE615A27 // 2^(61/64)data8 0x000F50765B6E4540 // 2^(62/64)data8 0x000FA7C1819E90D8 // 2^(63/64)LOCAL_OBJECT_END(_expf_table).section .textGLOBAL_IEEE754_ENTRY(expm1f){ .mlx getf.exp rSignexp_x = f8 // Must recompute if x unorm movl r64DivLn2 = 0x40571547652B82FE // 64/ln(2)}{ .mlx addl rTblAddr = @ltoff(_expf_table),gp movl rRightShifter = 0x43E8000000000000 // DP Right Shifter};;{ .mfi // point to the beginning of the table ld8 rTblAddr = [rTblAddr] fclass.m p14, p0 = f8 , 0x22 // test for -INF mov rExp_mask = 0x1ffff // Exponent mask}{ .mfi nop.m 0 fnorm.s1 fNormX = f8 // normalized x nop.i 0};;{ .mfi setf.d f64DivLn2 = r64DivLn2 // load 64/ln(2) to FP reg fclass.m p9, p0 = f8 , 0x0b // test for x unorm mov rExp_bias = 0xffff // Exponent bias}{ .mlx // load Right Shifter to FP reg setf.d fRightShifter = rRightShifter movl rLn2Div64 = 0x3F862E42FEFA39EF // DP ln(2)/64 in GR};;{ .mfi ldfpd fA8, fA7 = [rTblAddr], 16 fcmp.eq.s1 p13, p0 = f0, f8 // test for x = 0.0 mov rExp_half = 0xfffe}{ .mfb setf.d fLn2Div64 = rLn2Div64 // load ln(2)/64 to FP reg nop.f 0(p9) br.cond.spnt EXPM1_UNORM // Branch if x unorm};;EXPM1_COMMON:{ .mfb ldfpd fA6, fA5 = [rTblAddr], 16
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