.file "logf.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 //============================================================== // 03/01/00 Initial version // 08/15/00 Bundle added after call to __libm_error_support to properly // set [the previously overwritten] GR_Parameter_RESULT. // 01/10/01 Improved speed, fixed flags for neg denormals // 05/20/02 Cleaned up namespace and sf0 syntax // 05/23/02 Modified algorithm. Now only one polynomial is used // for |x-1| >= 1/256 and for |x-1| < 1/256 // 02/10/03 Reordered header: .section, .global, .proc, .align // 03/31/05 Reformatted delimiters between data tables // // API //============================================================== // float logf(float) // float log10f(float) // // // Overview of operation //============================================================== // Background // ---------- // // This algorithm is based on fact that // log(a b) = log(a) + log(b). // // In our case we have x = 2^N f, where 1 <= f < 2. // So // log(x) = log(2^N f) = log(2^N) + log(f) = n*log(2) + log(f) // // To calculate log(f) we do following // log(f) = log(f * frcpa(f) / frcpa(f)) = // = log(f * frcpa(f)) + log(1/frcpa(f)) // // According to definition of IA-64's frcpa instruction it's a // floating point that approximates 1/f using a lookup on the // top of 8 bits of the input number's significand with relative // error < 2^(-8.886). So we have following // // |(1/f - frcpa(f)) / (1/f))| = |1 - f*frcpa(f)| < 1/256 // // and // // log(f) = log(f * frcpa(f)) + log(1/frcpa(f)) = // = log(1 + r) + T // // The first value can be computed by polynomial P(r) approximating // log(1 + r) on |r| < 1/256 and the second is precomputed tabular // value defined by top 8 bit of f. // // Finally we have that log(x) ~ (N*log(2) + T) + P(r) // // Note that if input argument is close to 1.0 (in our case it means // that |1 - x| < 1/256) we can use just polynomial approximation // because x = 2^0 * f = f = 1 + r and // log(x) = log(1 + r) ~ P(r) // // // To compute log10(x) we just use identity: // // log10(x) = log(x)/log(10) // // so we have that // // log10(x) = (N*log(2) + T + log(1+r)) / log(10) = // = N*(log(2)/log(10)) + (T/log(10)) + log(1 + r)/log(10) // // // Implementation // -------------- // It can be seen that formulas for log and log10 differ from one another // only by coefficients and tabular values. Namely as log as log10 are // calculated as (N*L1 + T) + L2*Series(r) where in case of log // L1 = log(2) // T = log(1/frcpa(x)) // L2 = 1.0 // and in case of log10 // L1 = log(2)/log(10) // T = log(1/frcpa(x))/log(10) // L2 = 1.0/log(10) // // So common code with two different entry points those set pointers // to the base address of coresponding data sets containing values // of L2,T and prepare integer representation of L1 needed for following // setf instruction can be used. // // Note that both log and log10 use common approximation polynomial // it means we need only one set of coefficients of approximation. // // 1. Computation of log(x) for |x-1| >= 1/256 // InvX = frcpa(x) // r = InvX*x - 1 // P(r) = r*((1 - A2*r) + r^2*(A3 - A4*r)) = r*P2(r), // A4,A3,A2 are created with setf inctruction. // We use Taylor series and so A4 = 1/4, A3 = 1/3, // A2 = 1/2 rounded to double. // // N = float(n) where n is true unbiased exponent of x // // T is tabular value of log(1/frcpa(x)) calculated in quad precision // and rounded to double. To T we get bits from 55 to 62 of register // format significand of x and calculate address // ad_T = table_base_addr + 8 * index // // L2 (1.0 or 1.0/log(10) depending on function) is calculated in quad // precision and rounded to double; it's loaded from memory // // L1 (log(2) or log10(2) depending on function) is calculated in quad // precision and rounded to double; it's created with setf. // // And final result = P2(r)*(r*L2) + (T + N*L1) // // // 2. Computation of log(x) for |x-1| < 1/256 // r = x - 1 // P(r) = r*((1 - A2*r) + r^2*(A3 - A4*r)) = r*P2(r), // A4,A3,A2 are the same as in case |x-1| >= 1/256 // // And final result = P2(r)*(r*L2) // // 3. How we define is input argument such that |x-1| < 1/256 or not. // // To do it we analyze biased exponent and significand of input argument. // // a) First we test is biased exponent equal to 0xFFFE or 0xFFFF (i.e. // we test is 0.5 <= x < 2). This comparison can be performed using // unsigned version of cmp instruction in such a way // biased_exponent_of_x - 0xFFFE < 2 // // // b) Second (in case when result of a) is true) we need to compare x // with 1-1/256 and 1+1/256 or in register format representation with // 0xFFFEFF00000000000000 and 0xFFFF8080000000000000 correspondingly. // As far as biased exponent of x here can be equal only to 0xFFFE or // 0xFFFF we need to test only last bit of it. Also signifigand always // has implicit bit set to 1 that can be exluded from comparison. // Thus it's quite enough to generate 64-bit integer bits of that are // ix[63] = biased_exponent_of_x[0] and ix[62-0] = significand_of_x[62-0] // and compare it with 0x7F00000000000000 and 0x80800000000000000 (those // obtained like ix from register representatinos of 255/256 and // 257/256). This comparison can be made like in a), using unsigned // version of cmp i.e. ix - 0x7F00000000000000 < 0x0180000000000000. // 0x0180000000000000 is difference between 0x80800000000000000 and // 0x7F00000000000000. // // Note: NaT, any NaNs, +/-INF, +/-0, negatives and unnormalized numbers are // filtered and processed on special branches. // // // Special values //============================================================== // // logf(+0) = -inf // logf(-0) = -inf // // logf(+qnan) = +qnan // logf(-qnan) = -qnan // logf(+snan) = +qnan // logf(-snan) = -qnan // // logf(-n) = QNAN Indefinite // logf(-inf) = QNAN Indefinite // // logf(+inf) = +inf // // Registers used //============================================================== // Floating Point registers used: // f8, input // f12 -> f14, f33 -> f39 // // General registers used: // r8 -> r11 // r14 -> r19 // // Predicate registers used: // p6 -> p12 // Assembly macros //============================================================== GR_TAG = r8 GR_ad_T = r8 GR_N = r9 GR_Exp = r10 GR_Sig = r11 GR_025 = r14 GR_05 = r15 GR_A3 = r16 GR_Ind = r17 GR_dx = r15 GR_Ln2 = r19 GR_de = r20 GR_x = r21 GR_xorg = r22 GR_SAVE_B0 = r33 GR_SAVE_PFS = r34 GR_SAVE_GP = r35 GR_SAVE_SP = r36 GR_Parameter_X = r37 GR_Parameter_Y = r38 GR_Parameter_RESULT = r39 GR_Parameter_TAG = r40 FR_A2 = f12 FR_A3 = f13 FR_A4 = f14 FR_RcpX = f33 FR_r = f34 FR_r2 = f35 FR_tmp = f35 FR_Ln2 = f36 FR_T = f37 FR_N = f38 FR_NxLn2pT = f38 FR_NormX = f39 FR_InvLn10 = f40 FR_Y = f1 FR_X = f10 FR_RESULT = f8 // Data tables //============================================================== RODATA .align 16 LOCAL_OBJECT_START(logf_data) data8 0x3FF0000000000000 // 1.0 // // ln(1/frcpa(1+i/256)), i=0...255 data8 0x3F60040155D5889E // 0 data8 0x3F78121214586B54 // 1 data8 0x3F841929F96832F0 // 2 data8 0x3F8C317384C75F06 // 3 data8 0x3F91A6B91AC73386 // 4 data8 0x3F95BA9A5D9AC039 // 5 data8 0x3F99D2A8074325F4 // 6 data8 0x3F9D6B2725979802 // 7 data8 0x3FA0C58FA19DFAAA // 8 data8 0x3FA2954C78CBCE1B // 9 data8 0x3FA4A94D2DA96C56 // 10 data8 0x3FA67C94F2D4BB58 // 11 data8 0x3FA85188B630F068 // 12 data8 0x3FAA6B8ABE73AF4C // 13 data8 0x3FAC441E06F72A9E // 14 data8 0x3FAE1E6713606D07 // 15 data8 0x3FAFFA6911AB9301 // 16 data8 0x3FB0EC139C5DA601 // 17 data8 0x3FB1DBD2643D190B // 18 data8 0x3FB2CC7284FE5F1C // 19 data8 0x3FB3BDF5A7D1EE64 // 20 data8 0x3FB4B05D7AA012E0 // 21 data8 0x3FB580DB7CEB5702 // 22 data8 0x3FB674F089365A7A // 23 data8 0x3FB769EF2C6B568D // 24 data8 0x3FB85FD927506A48 // 25 data8 0x3FB9335E5D594989 // 26 data8 0x3FBA2B0220C8E5F5 // 27 data8 0x3FBB0004AC1A86AC // 28 data8 0x3FBBF968769FCA11 // 29 data8 0x3FBCCFEDBFEE13A8 // 30 data8 0x3FBDA727638446A2 // 31 data8 0x3FBEA3257FE10F7A // 32 data8 0x3FBF7BE9FEDBFDE6 // 33 data8 0x3FC02AB352FF25F4 // 34 data8 0x3FC097CE579D204D // 35 data8 0x3FC1178E8227E47C // 36 data8 0x3FC185747DBECF34 // 37 data8 0x3FC1F3B925F25D41 // 38 data8 0x3FC2625D1E6DDF57 // 39 data8 0x3FC2D1610C86813A // 40 data8 0x3FC340C59741142E // 41 data8 0x3FC3B08B6757F2A9 // 42 data8 0x3FC40DFB08378003 // 43 data8 0x3FC47E74E8CA5F7C // 44 data8 0x3FC4EF51F6466DE4 // 45 data8 0x3FC56092E02BA516 // 46 data8 0x3FC5D23857CD74D5 // 47 data8 0x3FC6313A37335D76 // 48 data8 0x3FC6A399DABBD383 // 49 data8 0x3FC70337DD3CE41B // 50 data8 0x3FC77654128F6127 // 51 data8 0x3FC7E9D82A0B022D // 52 data8 0x3FC84A6B759F512F // 53 data8 0x3FC8AB47D5F5A310 // 54 data8 0x3FC91FE49096581B // 55 data8 0x3FC981634011AA75 // 56 data8 0x3FC9F6C407089664 // 57 data8 0x3FCA58E729348F43 // 58 data8 0x3FCABB55C31693AD // 59 data8 0x3FCB1E104919EFD0 // 60 data8 0x3FCB94EE93E367CB // 61 data8 0x3FCBF851C067555F // 62 data8 0x3FCC5C0254BF23A6 // 63 data8 0x3FCCC000C9DB3C52 // 64 data8 0x3FCD244D99C85674 // 65 data8 0x3FCD88E93FB2F450 // 66 data8 0x3FCDEDD437EAEF01 // 67 data8 0x3FCE530EFFE71012 // 68 data8 0x3FCEB89A1648B971 // 69 data8 0x3FCF1E75FADF9BDE // 70 data8 0x3FCF84A32EAD7C35 // 71 data8 0x3FCFEB2233EA07CD // 72 data8 0x3FD028F9C7035C1C // 73 data8 0x3FD05C8BE0D9635A // 74 data8 0x3FD085EB8F8AE797 // 75 data8 0x3FD0B9C8E32D1911 // 76 data8 0x3FD0EDD060B78081 // 77 data8 0x3FD122024CF0063F // 78 data8 0x3FD14BE2927AECD4 // 79 data8 0x3FD180618EF18ADF // 80 data8 0x3FD1B50BBE2FC63B // 81 data8 0x3FD1DF4CC7CF242D // 82 data8 0x3FD214456D0EB8D4 // 83 data8 0x3FD23EC5991EBA49 // 84 data8 0x3FD2740D9F870AFB // 85 data8 0x3FD29ECDABCDFA04 // 86 data8 0x3FD2D46602ADCCEE // 87 data8 0x3FD2FF66B04EA9D4 // 88 data8 0x3FD335504B355A37 // 89 data8 0x3FD360925EC44F5D // 90 data8 0x3FD38BF1C3337E75 // 91 data8 0x3FD3C25277333184 // 92 data8 0x3FD3EDF463C1683E // 93 data8 0x3FD419B423D5E8C7 // 94 data8 0x3FD44591E0539F49 // 95 data8 0x3FD47C9175B6F0AD // 96 data8 0x3FD4A8B341552B09 // 97 data8 0x3FD4D4F3908901A0 // 98 data8 0x3FD501528DA1F968 // 99 data8 0x3FD52DD06347D4F6 // 100 data8 0x3FD55A6D3C7B8A8A // 101 data8 0x3FD5925D2B112A59 // 102 data8 0x3FD5BF406B543DB2 // 103 data8 0x3FD5EC433D5C35AE // 104 data8 0x3FD61965CDB02C1F // 105 data8 0x3FD646A84935B2A2 // 106 data8 0x3FD6740ADD31DE94 // 107 data8 0x3FD6A18DB74A58C5 // 108 data8 0x3FD6CF31058670EC // 109 data8 0x3FD6F180E852F0BA // 110 data8 0x3FD71F5D71B894F0 // 111 data8 0x3FD74D5AEFD66D5C // 112 data8 0x3FD77B79922BD37E // 113 data8 0x3FD7A9B9889F19E2 // 114 data8 0x3FD7D81B037EB6A6 // 115 data8 0x3FD8069E33827231 // 116 data8 0x3FD82996D3EF8BCB // 117 data8 0x3FD85855776DCBFB // 118 data8 0x3FD8873658327CCF // 119 data8 0x3FD8AA75973AB8CF // 120 data8 0x3FD8D992DC8824E5 // 121 data8 0x3FD908D2EA7D9512 // 122 data8 0x3FD92C59E79C0E56 // 123 data8 0x3FD95BD750EE3ED3 // 124 data8 0x3FD98B7811A3EE5B // 125 data8 0x3FD9AF47F33D406C // 126 data8 0x3FD9DF270C1914A8 // 127 data8 0x3FDA0325ED14FDA4 // 128 data8 0x3FDA33440224FA79 // 129 data8 0x3FDA57725E80C383 // 130 data8 0x3FDA87D0165DD199 // 131 data8 0x3FDAAC2E6C03F896 // 132 data8 0x3FDADCCC6FDF6A81 // 133 data8 0x3FDB015B3EB1E790 // 134 data8 0x3FDB323A3A635948 // 135 data8 0x3FDB56FA04462909 // 136 data8 0x3FDB881AA659BC93 // 137 data8 0x3FDBAD0BEF3DB165 // 138 data8 0x3FDBD21297781C2F // 139 data8 0x3FDC039236F08819 // 140 data8 0x3FDC28CB1E4D32FD // 141 data8 0x3FDC4E19B84723C2 // 142 data8 0x3FDC7FF9C74554C9 // 143 data8 0x3FDCA57B64E9DB05 // 144 data8 0x3FDCCB130A5CEBB0 // 145 data8 0x3FDCF0C0D18F326F // 146 data8 0x3FDD232075B5A201 // 147 data8 0x3FDD490246DEFA6B // 148 data8 0x3FDD6EFA918D25CD // 149 data8 0x3FDD9509707AE52F // 150 data8 0x3FDDBB2EFE92C554 // 151 data8 0x3FDDEE2F3445E4AF // 152 data8 0x3FDE148A1A2726CE // 153 data8 0x3FDE3AFC0A49FF40 // 154 data8 0x3FDE6185206D516E // 155 data8 0x3FDE882578823D52 // 156 data8 0x3FDEAEDD2EAC990C // 157 data8 0x3FDED5AC5F436BE3 // 158 data8 0x3FDEFC9326D16AB9 // 159 data8 0x3FDF2391A2157600 // 160 data8 0x3FDF4AA7EE03192D // 161 data8 0x3FDF71D627C30BB0 // 162 data8 0x3FDF991C6CB3B379 // 163 data8 0x3FDFC07ADA69A910 // 164 data8 0x3FDFE7F18EB03D3E // 165 data8 0x3FE007C053C5002E // 166 data8 0x3FE01B942198A5A1 // 167 data8 0x3FE02F74400C64EB // 168 data8 0x3FE04360BE7603AD // 169 data8 0x3FE05759AC47FE34 // 170 data8 0x3FE06B5F1911CF52 // 171 data8 0x3FE078BF0533C568 // 172 data8 0x3FE08CD9687E7B0E // 173 data8 0x3FE0A10074CF9019 // 174 data8 0x3FE0B5343A234477 // 175 data8 0x3FE0C974C89431CE // 176 data8 0x3FE0DDC2305B9886 // 177 data8 0x3FE0EB524BAFC918 // 178 data8 0x3FE0FFB54213A476 // 179 data8 0x3FE114253DA97D9F // 180 data8 0x3FE128A24F1D9AFF // 181 data8 0x3FE1365252BF0865 // 182 data8 0x3FE14AE558B4A92D // 183 data8 0x3FE15F85A19C765B // 184 data8 0x3FE16D4D38C119FA // 185 data8 0x3FE18203C20DD133 // 186 data8 0x3FE196C7BC4B1F3B // 187 data8 0x3FE1A4A738B7A33C // 188 data8 0x3FE1B981C0C9653D // 189 data8 0x3FE1CE69E8BB106B // 190 data8 0x3FE1DC619DE06944 // 191 data8 0x3FE1F160A2AD0DA4 // 192 data8 0x3FE2066D7740737E // 193 data8 0x3FE2147DBA47A394 // 194 data8 0x3FE229A1BC5EBAC3 // 195 data8 0x3FE237C1841A502E // 196 data8 0x3FE24CFCE6F80D9A // 197 data8 0x3FE25B2C55CD5762 // 198 data8 0x3FE2707F4D5F7C41 // 199 data8 0x3FE285E0842CA384 // 200 data8 0x3FE294294708B773 // 201 data8 0x3FE2A9A2670AFF0C // 202 data8 0x3FE2B7FB2C8D1CC1 // 203 data8 0x3FE2C65A6395F5F5 // 204 data8 0x3FE2DBF557B0DF43 // 205 data8 0x3FE2EA64C3F97655 // 206 data8 0x3FE3001823684D73 // 207 data8 0x3FE30E97E9A8B5CD // 208 data8 0x3FE32463EBDD34EA // 209 data8 0x3FE332F4314AD796 // 210 data8 0x3FE348D90E7464D0 // 211 data8 0x3FE35779F8C43D6E // 212 data8 0x3FE36621961A6A99 // 213 data8 0x3FE37C299F3C366A // 214 data8 0x3FE38AE2171976E7 // 215 data8 0x3FE399A157A603E7 // 216 data8 0x3FE3AFCCFE77B9D1 // 217 data8 0x3FE3BE9D503533B5 // 218 data8 0x3FE3CD7480B4A8A3 // 219 data8 0x3FE3E3C43918F76C // 220 data8 0x3FE3F2ACB27ED6C7 // 221 data8 0x3FE4019C2125CA93 // 222 data8 0x3FE4181061389722 // 223 data8 0x3FE42711518DF545 // 224 data8 0x3FE436194E12B6BF // 225 data8 0x3FE445285D68EA69 // 226 data8 0x3FE45BCC464C893A // 227 data8 0x3FE46AED21F117FC // 228 data8 0x3FE47A1527E8A2D3 // 229 data8 0x3FE489445EFFFCCC // 230 data8 0x3FE4A018BCB69835 // 231 data8 0x3FE4AF5A0C9D65D7 // 232 data8 0x3FE4BEA2A5BDBE87 // 233 data8 0x3FE4CDF28F10AC46 // 234 data8 0x3FE4DD49CF994058 // 235 data8 0x3FE4ECA86E64A684 // 236 data8 0x3FE503C43CD8EB68 // 237 data8 0x3FE513356667FC57 // 238 data8 0x3FE522AE0738A3D8 // 239 data8 0x3FE5322E26867857 // 240 data8 0x3FE541B5CB979809 // 241 data8 0x3FE55144FDBCBD62 // 242 data8 0x3FE560DBC45153C7 // 243 data8 0x3FE5707A26BB8C66 // 244 data8 0x3FE587F60ED5B900 // 245 data8 0x3FE597A7977C8F31 // 246 data8 0x3FE5A760D634BB8B // 247 data8 0x3FE5B721D295F10F // 248 data8 0x3FE5C6EA94431EF9 // 249 data8 0x3FE5D6BB22EA86F6 // 250 data8 0x3FE5E6938645D390 // 251 data8 0x3FE5F673C61A2ED2 // 252 data8 0x3FE6065BEA385926 // 253 data8 0x3FE6164BFA7CC06B // 254 data8 0x3FE62643FECF9743 // 255 LOCAL_OBJECT_END(logf_data) LOCAL_OBJECT_START(log10f_data) data8 0x3FDBCB7B1526E50E // 1/ln(10) // // ln(1/frcpa(1+i/256))/ln(10), i=0...255 data8 0x3F4BD27045BFD025 // 0 data8 0x3F64E84E793A474A // 1 data8 0x3F7175085AB85FF0 // 2 data8 0x3F787CFF9D9147A5 // 3 data8 0x3F7EA9D372B89FC8 // 4 data8 0x3F82DF9D95DA961C // 5 data8 0x3F866DF172D6372C // 6 data8 0x3F898D79EF5EEDF0 // 7 data8 0x3F8D22ADF3F9579D // 8 data8 0x3F9024231D30C398 // 9 data8 0x3F91F23A98897D4A // 10 data8 0x3F93881A7B818F9E // 11 data8 0x3F951F6E1E759E35 // 12 data8 0x3F96F2BCE7ADC5B4 // 13 data8 0x3F988D362CDF359E // 14 data8 0x3F9A292BAF010982 // 15 data8 0x3F9BC6A03117EB97 // 16 data8 0x3F9D65967DE3AB09 // 17 data8 0x3F9F061167FC31E8 // 18 data8 0x3FA05409E4F7819C // 19 data8 0x3FA125D0432EA20E // 20 data8 0x3FA1F85D440D299B // 21 data8 0x3FA2AD755749617D // 22 data8 0x3FA381772A00E604 // 23 data8 0x3FA45643E165A70B // 24 data8 0x3FA52BDD034475B8 // 25 data8 0x3FA5E3966B7E9295 // 26 data8 0x3FA6BAAF47C5B245 // 27 data8 0x3FA773B3E8C4F3C8 // 28 data8 0x3FA84C51EBEE8D15 // 29 data8 0x3FA906A6786FC1CB // 30 data8 0x3FA9C197ABF00DD7 // 31 data8 0x3FAA9C78712191F7 // 32 data8 0x3FAB58C09C8D637C // 33 data8 0x3FAC15A8BCDD7B7E // 34 data8 0x3FACD331E2C2967C // 35 data8 0x3FADB11ED766ABF4 // 36 data8 0x3FAE70089346A9E6 // 37 data8 0x3FAF2F96C6754AEE // 38 data8 0x3FAFEFCA8D451FD6 // 39 data8 0x3FB0585283764178 // 40 data8 0x3FB0B913AAC7D3A7 // 41 data8 0x3FB11A294F2569F6 // 42 data8 0x3FB16B51A2696891 // 43 data8 0x3FB1CD03ADACC8BE // 44 data8 0x3FB22F0BDD7745F5 // 45 data8 0x3FB2916ACA38D1E8 // 46 data8 0x3FB2F4210DF7663D // 47 data8 0x3FB346A6C3C49066 // 48 data8 0x3FB3A9FEBC60540A // 49 data8 0x3FB3FD0C10A3AA54 // 50 data8 0x3FB46107D3540A82 // 51 data8 0x3FB4C55DD16967FE // 52 data8 0x3FB51940330C000B // 53 data8 0x3FB56D620EE7115E // 54 data8 0x3FB5D2ABCF26178E // 55 data8 0x3FB6275AA5DEBF81 // 56 data8 0x3FB68D4EAF26D7EE // 57 data8 0x3FB6E28C5C54A28D // 58 data8 0x3FB7380B9665B7C8 // 59 data8 0x3FB78DCCC278E85B // 60 data8 0x3FB7F50C2CF2557A // 61 data8 0x3FB84B5FD5EAEFD8 // 62 data8 0x3FB8A1F6BAB2B226 // 63 data8 0x3FB8F8D144557BDF // 64 data8 0x3FB94FEFDCD61D92 // 65 data8 0x3FB9A752EF316149 // 66 data8 0x3FB9FEFAE7611EE0 // 67 data8 0x3FBA56E8325F5C87 // 68 data8 0x3FBAAF1B3E297BB4 // 69 data8 0x3FBB079479C372AD // 70 data8 0x3FBB6054553B12F7 // 71 data8 0x3FBBB95B41AB5CE6 // 72 data8 0x3FBC12A9B13FE079 // 73 data8 0x3FBC6C4017382BEA // 74 data8 0x3FBCB41FBA42686D // 75 data8 0x3FBD0E38CE73393F // 76 data8 0x3FBD689B2193F133 // 77 data8 0x3FBDC3472B1D2860 // 78 data8 0x3FBE0C06300D528B // 79 data8 0x3FBE6738190E394C // 80 data8 0x3FBEC2B50D208D9B // 81 data8 0x3FBF0C1C2B936828 // 82 data8 0x3FBF68216C9CC727 // 83 data8 0x3FBFB1F6381856F4 // 84 data8 0x3FC00742AF4CE5F8 // 85 data8 0x3FC02C64906512D2 // 86 data8 0x3FC05AF1E63E03B4 // 87 data8 0x3FC0804BEA723AA9 // 88 data8 0x3FC0AF1FD6711527 // 89 data8 0x3FC0D4B2A8805A00 // 90 data8 0x3FC0FA5EF136A06C // 91 data8 0x3FC1299A4FB3E306 // 92 data8 0x3FC14F806253C3ED // 93 data8 0x3FC175805D1587C1 // 94 data8 0x3FC19B9A637CA295 // 95 data8 0x3FC1CB5FC26EDE17 // 96 data8 0x3FC1F1B4E65F2590 // 97 data8 0x3FC218248B5DC3E5 // 98 data8 0x3FC23EAED62ADC76 // 99 data8 0x3FC26553EBD337BD // 100 data8 0x3FC28C13F1B11900 // 101 data8 0x3FC2BCAA14381386 // 102 data8 0x3FC2E3A740B7800F // 103 data8 0x3FC30ABFD8F333B6 // 104 data8 0x3FC331F403985097 // 105 data8 0x3FC35943E7A60690 // 106 data8 0x3FC380AFAC6E7C07 // 107 data8 0x3FC3A8377997B9E6 // 108 data8 0x3FC3CFDB771C9ADB // 109 data8 0x3FC3EDA90D39A5DF // 110 data8 0x3FC4157EC09505CD // 111 data8 0x3FC43D7113FB04C1 // 112 data8 0x3FC4658030AD1CCF // 113 data8 0x3FC48DAC404638F6 // 114 data8 0x3FC4B5F56CBBB869 // 115 data8 0x3FC4DE5BE05E7583 // 116 data8 0x3FC4FCBC0776FD85 // 117 data8 0x3FC525561E9256EE // 118 data8 0x3FC54E0DF3198865 // 119 data8 0x3FC56CAB7112BDE2 // 120 data8 0x3FC59597BA735B15 // 121 data8 0x3FC5BEA23A506FDA // 122 data8 0x3FC5DD7E08DE382F // 123 data8 0x3FC606BDD3F92355 // 124 data8 0x3FC6301C518A501F // 125 data8 0x3FC64F3770618916 // 126 data8 0x3FC678CC14C1E2D8 // 127 data8 0x3FC6981005ED2947 // 128 data8 0x3FC6C1DB5F9BB336 // 129 data8 0x3FC6E1488ECD2881 // 130 data8 0x3FC70B4B2E7E41B9 // 131 data8 0x3FC72AE209146BF9 // 132 data8 0x3FC7551C81BD8DCF // 133 data8 0x3FC774DD76CC43BE // 134 data8 0x3FC79F505DB00E88 // 135 data8 0x3FC7BF3BDE099F30 // 136 data8 0x3FC7E9E7CAC437F9 // 137 data8 0x3FC809FE4902D00D // 138 data8 0x3FC82A2757995CBE // 139 data8 0x3FC85525C625E098 // 140 data8 0x3FC8757A79831887 // 141 data8 0x3FC895E2058D8E03 // 142 data8 0x3FC8C13437695532 // 143 data8 0x3FC8E1C812EF32BE // 144 data8 0x3FC9026F112197E8 // 145 data8 0x3FC923294888880B // 146 data8 0x3FC94EEA4B8334F3 // 147 data8 0x3FC96FD1B639FC09 // 148 data8 0x3FC990CCA66229AC // 149 data8 0x3FC9B1DB33334843 // 150 data8 0x3FC9D2FD740E6607 // 151 data8 0x3FC9FF49EEDCB553 // 152 data8 0x3FCA209A84FBCFF8 // 153 data8 0x3FCA41FF1E43F02B // 154 data8 0x3FCA6377D2CE9378 // 155 data8 0x3FCA8504BAE0D9F6 // 156 data8 0x3FCAA6A5EEEBEFE3 // 157 data8 0x3FCAC85B878D7879 // 158 data8 0x3FCAEA259D8FFA0B // 159 data8 0x3FCB0C0449EB4B6B // 160 data8 0x3FCB2DF7A5C50299 // 161 data8 0x3FCB4FFFCA70E4D1 // 162 data8 0x3FCB721CD17157E3 // 163 data8 0x3FCB944ED477D4ED // 164 data8 0x3FCBB695ED655C7D // 165 data8 0x3FCBD8F2364AEC0F // 166 data8 0x3FCBFB63C969F4FF // 167 data8 0x3FCC1DEAC134D4E9 // 168 data8 0x3FCC4087384F4F80 // 169 data8 0x3FCC6339498F09E2 // 170 data8 0x3FCC86010FFC076C // 171 data8 0x3FCC9D3D065C5B42 // 172 data8 0x3FCCC029375BA07A // 173 data8 0x3FCCE32B66978BA4 // 174 data8 0x3FCD0643AFD51404 // 175 data8 0x3FCD29722F0DEA45 // 176 data8 0x3FCD4CB70070FE44 // 177 data8 0x3FCD6446AB3F8C96 // 178 data8 0x3FCD87B0EF71DB45 // 179 data8 0x3FCDAB31D1FE99A7 // 180 data8 0x3FCDCEC96FDC888F // 181 data8 0x3FCDE6908876357A // 182 data8 0x3FCE0A4E4A25C200 // 183 data8 0x3FCE2E2315755E33 // 184 data8 0x3FCE461322D1648A // 185 data8 0x3FCE6A0E95C7787B // 186 data8 0x3FCE8E216243DD60 // 187 data8 0x3FCEA63AF26E007C // 188 data8 0x3FCECA74ED15E0B7 // 189 data8 0x3FCEEEC692CCD25A // 190 data8 0x3FCF070A36B8D9C1 // 191 data8 0x3FCF2B8393E34A2D // 192 data8 0x3FCF5014EF538A5B // 193 data8 0x3FCF68833AF1B180 // 194 data8 0x3FCF8D3CD9F3F04F // 195 data8 0x3FCFA5C61ADD93E9 // 196 data8 0x3FCFCAA8567EBA7A // 197 data8 0x3FCFE34CC8743DD8 // 198 data8 0x3FD0042BFD74F519 // 199 data8 0x3FD016BDF6A18017 // 200 data8 0x3FD023262F907322 // 201 data8 0x3FD035CCED8D32A1 // 202 data8 0x3FD042430E869FFC // 203 data8 0x3FD04EBEC842B2E0 // 204 data8 0x3FD06182E84FD4AC // 205 data8 0x3FD06E0CB609D383 // 206 data8 0x3FD080E60BEC8F12 // 207 data8 0x3FD08D7E0D894735 // 208 data8 0x3FD0A06CC96A2056 // 209 data8 0x3FD0AD131F3B3C55 // 210 data8 0x3FD0C01771E775FB // 211 data8 0x3FD0CCCC3CAD6F4B // 212 data8 0x3FD0D986D91A34A9 // 213 data8 0x3FD0ECA9B8861A2D // 214 data8 0x3FD0F972F87FF3D6 // 215 data8 0x3FD106421CF0E5F7 // 216 data8 0x3FD11983EBE28A9D // 217 data8 0x3FD12661E35B785A // 218 data8 0x3FD13345D2779D3B // 219 data8 0x3FD146A6F597283A // 220 data8 0x3FD15399E81EA83D // 221 data8 0x3FD16092E5D3A9A6 // 222 data8 0x3FD17413C3B7AB5E // 223 data8 0x3FD1811BF629D6FB // 224 data8 0x3FD18E2A47B46686 // 225 data8 0x3FD19B3EBE1A4418 // 226 data8 0x3FD1AEE9017CB450 // 227 data8 0x3FD1BC0CED7134E2 // 228 data8 0x3FD1C93712ABC7FF // 229 data8 0x3FD1D66777147D3F // 230 data8 0x3FD1EA3BD1286E1C // 231 data8 0x3FD1F77BED932C4C // 232 data8 0x3FD204C25E1B031F // 233 data8 0x3FD2120F28CE69B1 // 234 data8 0x3FD21F6253C48D01 // 235 data8 0x3FD22CBBE51D60AA // 236 data8 0x3FD240CE4C975444 // 237 data8 0x3FD24E37F8ECDAE8 // 238 data8 0x3FD25BA8215AF7FC // 239 data8 0x3FD2691ECC29F042 // 240 data8 0x3FD2769BFFAB2E00 // 241 data8 0x3FD2841FC23952C9 // 242 data8 0x3FD291AA1A384978 // 243 data8 0x3FD29F3B0E15584B // 244 data8 0x3FD2B3A0EE479DF7 // 245 data8 0x3FD2C142842C09E6 // 246 data8 0x3FD2CEEACCB7BD6D // 247 data8 0x3FD2DC99CE82FF21 // 248 data8 0x3FD2EA4F902FD7DA // 249 data8 0x3FD2F80C186A25FD // 250 data8 0x3FD305CF6DE7B0F7 // 251 data8 0x3FD3139997683CE7 // 252 data8 0x3FD3216A9BB59E7C // 253 data8 0x3FD32F4281A3CEFF // 254 data8 0x3FD33D2150110092 // 255 LOCAL_OBJECT_END(log10f_data) // Code //============================================================== .section .text // logf has p13 true, p14 false // log10f has p14 true, p13 false GLOBAL_IEEE754_ENTRY(log10f) { .mfi getf.exp GR_Exp = f8 // if x is unorm then must recompute frcpa.s1 FR_RcpX,p0 = f1,f8 mov GR_05 = 0xFFFE // biased exponent of A2=0.5 } { .mlx addl GR_ad_T = @ltoff(log10f_data),gp movl GR_A3 = 0x3FD5555555555555 // double precision memory // representation of A3 };; { .mfi getf.sig GR_Sig = f8 // if x is unorm then must recompute fclass.m p8,p0 = f8,9 // is x positive unorm? sub GR_025 = GR_05,r0,1 // biased exponent of A4=0.25 } { .mlx ld8 GR_ad_T = [GR_ad_T] movl GR_Ln2 = 0x3FD34413509F79FF // double precision memory // representation of // log(2)/ln(10) };; { .mfi setf.d FR_A3 = GR_A3 // create A3 fcmp.eq.s1 p14,p13 = f0,f0 // set p14 to 1 for log10f dep.z GR_xorg = GR_05,55,8 // 0x7F00000000000000 integer number // bits of that are // GR_xorg[63] = last bit of biased // exponent of 255/256 // GR_xorg[62-0] = bits from 62 to 0 // of significand of 255/256 } { .mib setf.exp FR_A2 = GR_05 // create A2 sub GR_de = GR_Exp,GR_05 // biased_exponent_of_x - 0xFFFE // needed for comparison with 0.5 and 2.0 br.cond.sptk logf_log10f_common };; GLOBAL_IEEE754_END(log10f) GLOBAL_IEEE754_ENTRY(logf) { .mfi getf.exp GR_Exp = f8 // if x is unorm then must recompute frcpa.s1 FR_RcpX,p0 = f1,f8 mov GR_05 = 0xFFFE // biased exponent of A2=-0.5 } { .mlx addl GR_ad_T = @ltoff(logf_data),gp movl GR_A3 = 0x3FD5555555555555 // double precision memory // representation of A3 };; { .mfi getf.sig GR_Sig = f8 // if x is unorm then must recompute fclass.m p8,p0 = f8,9 // is x positive unorm? dep.z GR_xorg = GR_05,55,8 // 0x7F00000000000000 integer number // bits of that are // GR_xorg[63] = last bit of biased // exponent of 255/256 // GR_xorg[62-0] = bits from 62 to 0 // of significand of 255/256 } { .mfi ld8 GR_ad_T = [GR_ad_T] nop.f 0 sub GR_025 = GR_05,r0,1 // biased exponent of A4=0.25 };; { .mfi setf.d FR_A3 = GR_A3 // create A3 fcmp.eq.s1 p13,p14 = f0,f0 // p13 - true for logf sub GR_de = GR_Exp,GR_05 // biased_exponent_of_x - 0xFFFE // needed for comparison with 0.5 and 2.0 } { .mlx setf.exp FR_A2 = GR_05 // create A2 movl GR_Ln2 = 0x3FE62E42FEFA39EF // double precision memory // representation of log(2) };; logf_log10f_common: { .mfi setf.exp FR_A4 = GR_025 // create A4=0.25 fclass.m p9,p0 = f8,0x3A // is x < 0 (including negateve unnormals)? dep GR_x = GR_Exp,GR_Sig,63,1 // produce integer that bits are // GR_x[63] = GR_Exp[0] // GR_x[62-0] = GR_Sig[62-0] } { .mib sub GR_N = GR_Exp,GR_05,1 // unbiased exponent of x cmp.gtu p6,p7 = 2,GR_de // is 0.5 <= x < 2.0? (p8) br.cond.spnt logf_positive_unorm };; logf_core: { .mfi setf.sig FR_N = GR_N // copy unbiased exponent of x to the // significand field of FR_N fclass.m p10,p0 = f8,0x1E1 // is x NaN, NaT or +Inf? dep.z GR_dx = GR_05,54,3 // 0x0180000000000000 - difference // between our integer representations // of 257/256 and 255/256 } { .mfi nop.m 0 nop.f 0 sub GR_x = GR_x,GR_xorg // difference between representations // of x and 255/256 };; { .mfi ldfd FR_InvLn10 = [GR_ad_T],8 fcmp.eq.s1 p11,p0 = f8,f1 // is x equal to 1.0? extr.u GR_Ind = GR_Sig,55,8 // get bits from 55 to 62 as index } { .mib setf.d FR_Ln2 = GR_Ln2 // create log(2) or log10(2) (p6) cmp.gtu p6,p7 = GR_dx,GR_x // set p6 if 255/256 <= x < 257/256 (p9) br.cond.spnt logf_negatives // jump if input argument is negative number };; // p6 is true if |x-1| < 1/256 // p7 is true if |x-1| >= 1/256 .pred.rel "mutex",p6,p7 { .mfi shladd GR_ad_T = GR_Ind,3,GR_ad_T // calculate address of T (p7) fms.s1 FR_r = FR_RcpX,f8,f1 // range reduction for |x-1|>=1/256 extr.u GR_Exp = GR_Exp,0,17 // exponent without sign } { .mfb nop.m 0 (p6) fms.s1 FR_r = f8,f1,f1 // range reduction for |x-1|<1/256 (p10) br.cond.spnt logf_nan_nat_pinf // exit for NaN, NaT or +Inf };; { .mfb ldfd FR_T = [GR_ad_T] // load T (p11) fma.s.s0 f8 = f0,f0,f0 (p11) br.ret.spnt b0 // exit for x = 1.0 };; { .mib nop.m 0 cmp.eq p12,p0 = r0,GR_Exp // is x +/-0? (here it's quite enough // only to compare exponent with 0 // because all unnormals already // have been filtered) (p12) br.cond.spnt logf_zeroes // Branch if input argument is +/-0 };; { .mfi nop.m 0 fnma.s1 FR_A2 = FR_A2,FR_r,f1 // A2*r+1 nop.i 0 } { .mfi nop.m 0 fma.s1 FR_r2 = FR_r,FR_r,f0 // r^2 nop.i 0 };; { .mfi nop.m 0 fcvt.xf FR_N = FR_N // convert integer N in significand of FR_N // to floating-point representation nop.i 0 } { .mfi nop.m 0 fnma.s1 FR_A3 = FR_A4,FR_r,FR_A3 // A4*r+A3 nop.i 0 };; { .mfi nop.m 0 fma.s1 FR_r = FR_r,FR_InvLn10,f0 // For log10f we have r/log(10) nop.i 0 } { .mfi nop.m 0 nop.f 0 nop.i 0 };; { .mfi nop.m 0 fma.s1 FR_A2 = FR_A3,FR_r2,FR_A2 // (A4*r+A3)*r^2+(A2*r+1) nop.i 0 } { .mfi nop.m 0 fma.s1 FR_NxLn2pT = FR_N,FR_Ln2,FR_T // N*Ln2+T nop.i 0 };; .pred.rel "mutex",p6,p7 { .mfi nop.m 0 (p7) fma.s.s0 f8 = FR_A2,FR_r,FR_NxLn2pT // result for |x-1|>=1/256 nop.i 0 } { .mfb nop.m 0 (p6) fma.s.s0 f8 = FR_A2,FR_r,f0 // result for |x-1|<1/256 br.ret.sptk b0 };; .align 32 logf_positive_unorm: { .mfi nop.m 0 (p8) fma.s0 f8 = f8,f1,f0 // Normalize & set D-flag nop.i 0 };; { .mfi getf.exp GR_Exp = f8 // recompute biased exponent nop.f 0 cmp.ne p6,p7 = r0,r0 // p6 <- 0, p7 <- 1 because // in case of unorm we are out // interval [255/256; 257/256] };; { .mfi getf.sig GR_Sig = f8 // recompute significand nop.f 0 nop.i 0 };; { .mib sub GR_N = GR_Exp,GR_05,1 // unbiased exponent N nop.i 0 br.cond.sptk logf_core // return into main path };; .align 32 logf_nan_nat_pinf: { .mfi nop.m 0 fma.s.s0 f8 = f8,f1,f0 // set V-flag nop.i 0 } { .mfb nop.m 0 nop.f 0 br.ret.sptk b0 // exit for NaN, NaT or +Inf };; .align 32 logf_zeroes: { .mfi nop.m 0 fmerge.s FR_X = f8,f8 // keep input argument for subsequent // call of __libm_error_support# nop.i 0 } { .mfi (p13) mov GR_TAG = 4 // set libm error in case of logf fms.s1 FR_tmp = f0,f0,f1 // -1.0 nop.i 0 };; { .mfi nop.m 0 frcpa.s0 f8,p0 = FR_tmp,f0 // log(+/-0) should be equal to -INF. // We can get it using frcpa because it // sets result to the IEEE-754 mandated // quotient of FR_tmp/f0. // As far as FR_tmp is -1 it'll be -INF nop.i 0 } { .mib (p14) mov GR_TAG = 10 // set libm error in case of log10f nop.i 0 br.cond.sptk logf_libm_err };; .align 32 logf_negatives: { .mfi (p13) mov GR_TAG = 5 // set libm error in case of logf fmerge.s FR_X = f8,f8 // keep input argument for subsequent // call of __libm_error_support# nop.i 0 };; { .mfi (p14) mov GR_TAG = 11 // set libm error in case of log10f frcpa.s0 f8,p0 = f0,f0 // log(negatives) should be equal to NaN. // We can get it using frcpa because it // sets result to the IEEE-754 mandated // quotient of f0/f0 i.e. NaN. nop.i 0 };; .align 32 logf_libm_err: { .mmi alloc r32 = ar.pfs,1,4,4,0 mov GR_Parameter_TAG = GR_TAG nop.i 0 };; GLOBAL_IEEE754_END(logf) // Stack operations when calling error support. // (1) (2) (3) (call) (4) // sp -> + psp -> + psp -> + sp -> + // | | | | // | | <- GR_Y R3 ->| <- GR_RESULT | -> f8 // | | | | // | <-GR_Y Y2->| Y2 ->| <- GR_Y | // | | | | // | | <- GR_X X1 ->| | // | | | | // sp-64 -> + sp -> + sp -> + + // save ar.pfs save b0 restore gp // save gp restore ar.pfs LOCAL_LIBM_ENTRY(__libm_error_region) .prologue { .mfi add GR_Parameter_Y=-32,sp // Parameter 2 value nop.f 0 .save ar.pfs,GR_SAVE_PFS mov GR_SAVE_PFS=ar.pfs // Save ar.pfs } { .mfi .fframe 64 add sp=-64,sp // Create new stack nop.f 0 mov GR_SAVE_GP=gp // Save gp };; { .mmi stfs [GR_Parameter_Y] = FR_Y,16 // STORE Parameter 2 on stack add GR_Parameter_X = 16,sp // Parameter 1 address .save b0, GR_SAVE_B0 mov GR_SAVE_B0=b0 // Save b0 };; .body { .mib stfs [GR_Parameter_X] = FR_X // STORE Parameter 1 on stack add GR_Parameter_RESULT = 0,GR_Parameter_Y // Parameter 3 address nop.b 0 } { .mib stfs [GR_Parameter_Y] = FR_RESULT // STORE Parameter 3 on stack add GR_Parameter_Y = -16,GR_Parameter_Y br.call.sptk b0=__libm_error_support# // Call error handling function };; { .mmi nop.m 0 nop.m 0 add GR_Parameter_RESULT = 48,sp };; { .mmi ldfs f8 = [GR_Parameter_RESULT] // Get return result off stack .restore sp add sp = 64,sp // Restore stack pointer mov b0 = GR_SAVE_B0 // Restore return address };; { .mib mov gp = GR_SAVE_GP // Restore gp mov ar.pfs = GR_SAVE_PFS // Restore ar.pfs br.ret.sptk b0 // Return };; LOCAL_LIBM_END(__libm_error_region) .type __libm_error_support#,@function .global __libm_error_support#