3 // Copyright (C) 2000, 2001, Intel Corporation
4 // All rights reserved.
6 // Contributed 2/2/2000 by John Harrison, Ted Kubaska, Bob Norin, Shane Story,
7 // and Ping Tak Peter Tang of the Computational Software Lab, Intel Corporation.
9 // Redistribution and use in source and binary forms, with or without
10 // modification, are permitted provided that the following conditions are
13 // * Redistributions of source code must retain the above copyright
14 // notice, this list of conditions and the following disclaimer.
16 // * Redistributions in binary form must reproduce the above copyright
17 // notice, this list of conditions and the following disclaimer in the
18 // documentation and/or other materials provided with the distribution.
20 // * The name of Intel Corporation may not be used to endorse or promote
21 // products derived from this software without specific prior written
24 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
25 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
26 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
27 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL INTEL OR ITS
28 // CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
29 // EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
30 // PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
31 // PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
32 // OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY OR TORT (INCLUDING
33 // NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
34 // SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
36 // Intel Corporation is the author of this code, and requests that all
37 // problem reports or change requests be submitted to it directly at
38 // http://developer.intel.com/opensource.
40 // *********************************************************************
43 // 2/02/00 hand-optimized
44 // 4/04/00 Unwind support added
45 // 8/15/00 Bundle added after call to __libm_error_support to properly
46 // set [the previously overwritten] GR_Parameter_RESULT.
48 // *********************************************************************
50 // *********************************************************************
52 // Function: Combined logl(x), log1pl(x), and log10l(x) where
53 // logl(x) = ln(x), for double-extended precision x values
54 // log1pl(x) = ln(x+1), for double-extended precision x values
55 // log10l(x) = log (x), for double-extended precision x values
58 // *********************************************************************
62 // Floating-Point Registers: f8 (Input and Return Value)
65 // General Purpose Registers:
67 // r54-r57 (Used to pass arguments to error handling routine)
69 // Predicate Registers: p6-p15
71 // *********************************************************************
73 // IEEE Special Conditions:
75 // Denormal fault raised on denormal inputs
76 // Overflow exceptions cannot occur
77 // Underflow exceptions raised when appropriate for log1p
78 // (Error Handling Routine called for underflow)
79 // Inexact raised when appropriate by algorithm
86 // logl(EM_special Values) = QNaN
88 // log1pl(-inf) = QNaN
89 // log1pl(+/-0) = +/-0
91 // log1pl(SNaN) = QNaN
92 // log1pl(QNaN) = QNaN
93 // log1pl(EM_special Values) = QNaN
95 // log10l(-inf) = QNaN
96 // log10l(+/-0) = -inf
97 // log10l(SNaN) = QNaN
98 // log10l(QNaN) = QNaN
99 // log10l(EM_special Values) = QNaN
101 // *********************************************************************
103 // Computation is based on the following kernel.
105 // ker_log_64( in_FR : X,
108 // in_GR : Expo_Range,
116 // The method consists of three cases.
118 // If |X+Em1| < 2^(-80) use case log1pl_small;
119 // elseif |X+Em1| < 2^(-7) use case log_near1;
120 // else use case log_regular;
122 // Case log1pl_small:
124 // logl( 1 + (X+Em1) ) can be approximated by (X+Em1).
128 // logl( 1 + (X+Em1) ) can be approximated by a simple polynomial
129 // in W = X+Em1. This polynomial resembles the truncated Taylor
130 // series W - W^/2 + W^3/3 - ...
134 // Here we use a table lookup method. The basic idea is that in
135 // order to compute logl(Arg) for an argument Arg in [1,2), we
136 // construct a value G such that G*Arg is close to 1 and that
137 // logl(1/G) is obtainable easily from a table of values calculated
140 // logl(Arg) = logl(1/G) + logl(G*Arg)
141 // = logl(1/G) + logl(1 + (G*Arg - 1))
143 // Because |G*Arg - 1| is small, the second term on the right hand
144 // side can be approximated by a short polynomial. We elaborate
145 // this method in four steps.
147 // Step 0: Initialization
149 // We need to calculate logl( E + X ). Obtain N, S_hi, S_lo such that
151 // E + X = 2^N * ( S_hi + S_lo ) exactly
153 // where S_hi in [1,2) and S_lo is a correction to S_hi in the sense
154 // that |S_lo| <= ulp(S_hi).
156 // Step 1: Argument Reduction
158 // Based on S_hi, obtain G_1, G_2, G_3 from a table and calculate
160 // G := G_1 * G_2 * G_3
161 // r := (G * S_hi - 1) + G * S_lo
163 // These G_j's have the property that the product is exactly
164 // representable and that |r| < 2^(-12) as a result.
166 // Step 2: Approximation
169 // logl(1 + r) is approximated by a short polynomial poly(r).
171 // Step 3: Reconstruction
174 // Finally, logl( E + X ) is given by
176 // logl( E + X ) = logl( 2^N * (S_hi + S_lo) )
177 // ~=~ N*logl(2) + logl(1/G) + logl(1 + r)
178 // ~=~ N*logl(2) + logl(1/G) + poly(r).
180 // **** Algorithm ****
182 // Case log1pl_small:
184 // Although logl(1 + (X+Em1)) is basically X+Em1, we would like to
185 // preserve the inexactness nature as well as consistent behavior
186 // under different rounding modes. Note that this case can only be
187 // taken if E is set to be 1.0. In this case, Em1 is zero, and that
188 // X can be very tiny and thus the final result can possibly underflow.
189 // Thus, we compare X against a threshold that is dependent on the
190 // input Expo_Range. If |X| is smaller than this threshold, we set
193 // The result is returned as Y_hi, Y_lo, and in the case of SAFE
194 // is FALSE, an additional value Scale is also returned.
197 // Threshold := Threshold_Table( Expo_Range )
198 // Tiny := Tiny_Table( Expo_Range )
200 // If ( |W| > Threshold ) then
211 // One may think that Y_lo should be -W*W/2; however, it does not matter
212 // as Y_lo will be rounded off completely except for the correct effect in
213 // directed rounding. Clearly -W*W is simplier to compute. Moreover,
214 // because of the difference in exponent value, Y_hi + Y_lo or
215 // Y_hi + Scale*Y_lo is always inexact.
219 // Here we compute a simple polynomial. To exploit parallelism, we split
220 // the polynomial into two portions.
226 // Y_hi := W + Wsq*(P_1 + W*(P_2 + W*(P_3 + W*P_4))
227 // Y_lo := W6*(P_5 + W*(P_6 + W*(P_7 + W*P_8)))
228 // set lsb(Y_lo) to be 1
232 // We present the algorithm in four steps.
234 // Step 0. Initialization
235 // ----------------------
238 // N := unbaised exponent of Z
239 // S_hi := 2^(-N) * Z
240 // S_lo := 2^(-N) * { (max(X,E)-Z) + min(X,E) }
242 // Note that S_lo is always 0 for the case E = 0.
244 // Step 1. Argument Reduction
245 // --------------------------
249 // Z = 2^N * S_hi = 2^N * 1.d_1 d_2 d_3 ... d_63
251 // We obtain G_1, G_2, G_3 by the following steps.
254 // Define X_0 := 1.d_1 d_2 ... d_14. This is extracted
257 // Define A_1 := 1.d_1 d_2 d_3 d_4. This is X_0 truncated
260 // Define index_1 := [ d_1 d_2 d_3 d_4 ].
262 // Fetch Z_1 := (1/A_1) rounded UP in fixed point with
263 // fixed point lsb = 2^(-15).
264 // Z_1 looks like z_0.z_1 z_2 ... z_15
265 // Note that the fetching is done using index_1.
266 // A_1 is actually not needed in the implementation
267 // and is used here only to explain how is the value
270 // Fetch G_1 := (1/A_1) truncated to 21 sig. bits.
271 // floating pt. Again, fetching is done using index_1. A_1
272 // explains how G_1 is defined.
274 // Calculate X_1 := X_0 * Z_1 truncated to lsb = 2^(-14)
275 // = 1.0 0 0 0 d_5 ... d_14
276 // This is accomplised by integer multiplication.
277 // It is proved that X_1 indeed always begin
278 // with 1.0000 in fixed point.
281 // Define A_2 := 1.0 0 0 0 d_5 d_6 d_7 d_8. This is X_1
282 // truncated to lsb = 2^(-8). Similar to A_1,
283 // A_2 is not needed in actual implementation. It
284 // helps explain how some of the values are defined.
286 // Define index_2 := [ d_5 d_6 d_7 d_8 ].
288 // Fetch Z_2 := (1/A_2) rounded UP in fixed point with
289 // fixed point lsb = 2^(-15). Fetch done using index_2.
290 // Z_2 looks like z_0.z_1 z_2 ... z_15
292 // Fetch G_2 := (1/A_2) truncated to 21 sig. bits.
295 // Calculate X_2 := X_1 * Z_2 truncated to lsb = 2^(-14)
296 // = 1.0 0 0 0 0 0 0 0 d_9 d_10 ... d_14
297 // This is accomplised by integer multiplication.
298 // It is proved that X_2 indeed always begin
299 // with 1.00000000 in fixed point.
302 // Define A_3 := 1.0 0 0 0 0 0 0 0 d_9 d_10 d_11 d_12 d_13 1.
303 // This is 2^(-14) + X_2 truncated to lsb = 2^(-13).
305 // Define index_3 := [ d_9 d_10 d_11 d_12 d_13 ].
307 // Fetch G_3 := (1/A_3) truncated to 21 sig. bits.
308 // floating pt. Fetch is done using index_3.
310 // Compute G := G_1 * G_2 * G_3.
312 // This is done exactly since each of G_j only has 21 sig. bits.
316 // r := (G*S_hi - 1) + G*S_lo using 2 FMA operations.
318 // thus, r approximates G*(S_hi+S_lo) - 1 to within a couple of
322 // Step 2. Approximation
323 // ---------------------
325 // This step computes an approximation to logl( 1 + r ) where r is the
326 // reduced argument just obtained. It is proved that |r| <= 1.9*2^(-13);
327 // thus logl(1+r) can be approximated by a short polynomial:
329 // logl(1+r) ~=~ poly = r + Q1 r^2 + ... + Q4 r^5
332 // Step 3. Reconstruction
333 // ----------------------
335 // This step computes the desired result of logl(X+E):
337 // logl(X+E) = logl( 2^N * (S_hi + S_lo) )
338 // = N*logl(2) + logl( S_hi + S_lo )
339 // = N*logl(2) + logl(1/G) +
340 // logl(1 + C*(S_hi+S_lo) - 1 )
342 // logl(2), logl(1/G_j) are stored as pairs of (single,double) numbers:
343 // log2_hi, log2_lo, log1byGj_hi, log1byGj_lo. The high parts are
344 // single-precision numbers and the low parts are double precision
345 // numbers. These have the property that
347 // N*log2_hi + SUM ( log1byGj_hi )
349 // is computable exactly in double-extended precision (64 sig. bits).
352 // Y_hi := N*log2_hi + SUM ( log1byGj_hi )
353 // Y_lo := poly_hi + [ poly_lo +
354 // ( SUM ( log1byGj_lo ) + N*log2_lo ) ]
355 // set lsb(Y_lo) to be 1
358 #include "libm_support.h"
366 // P_7, P_6, P_5, P_4, P_3, P_2, and P_1
370 ASM_TYPE_DIRECTIVE(Constants_P,@object)
371 data4 0xEFD62B15,0xE3936754,0x00003FFB,0x00000000
372 data4 0xA5E56381,0x8003B271,0x0000BFFC,0x00000000
373 data4 0x73282DB0,0x9249248C,0x00003FFC,0x00000000
374 data4 0x47305052,0xAAAAAA9F,0x0000BFFC,0x00000000
375 data4 0xCCD17FC9,0xCCCCCCCC,0x00003FFC,0x00000000
376 data4 0x00067ED5,0x80000000,0x0000BFFD,0x00000000
377 data4 0xAAAAAAAA,0xAAAAAAAA,0x00003FFD,0x00000000
378 data4 0xFFFFFFFE,0xFFFFFFFF,0x0000BFFD,0x00000000
379 ASM_SIZE_DIRECTIVE(Constants_P)
381 // log2_hi, log2_lo, Q_4, Q_3, Q_2, and Q_1
385 ASM_TYPE_DIRECTIVE(Constants_Q,@object)
386 data4 0x00000000,0xB1721800,0x00003FFE,0x00000000
387 data4 0x4361C4C6,0x82E30865,0x0000BFE2,0x00000000
388 data4 0x328833CB,0xCCCCCAF2,0x00003FFC,0x00000000
389 data4 0xA9D4BAFB,0x80000077,0x0000BFFD,0x00000000
390 data4 0xAAABE3D2,0xAAAAAAAA,0x00003FFD,0x00000000
391 data4 0xFFFFDAB7,0xFFFFFFFF,0x0000BFFD,0x00000000
392 ASM_SIZE_DIRECTIVE(Constants_Q)
394 // Z1 - 16 bit fixed, G1 and H1 - IEEE single
398 ASM_TYPE_DIRECTIVE(Constants_Z_G_H_h1,@object)
399 data4 0x00008000,0x3F800000,0x00000000,0x00000000,0x00000000,0x00000000
400 data4 0x00007879,0x3F70F0F0,0x3D785196,0x00000000,0x617D741C,0x3DA163A6
401 data4 0x000071C8,0x3F638E38,0x3DF13843,0x00000000,0xCBD3D5BB,0x3E2C55E6
402 data4 0x00006BCB,0x3F579430,0x3E2FF9A0,0x00000000,0xD86EA5E7,0xBE3EB0BF
403 data4 0x00006667,0x3F4CCCC8,0x3E647FD6,0x00000000,0x86B12760,0x3E2E6A8C
404 data4 0x00006187,0x3F430C30,0x3E8B3AE7,0x00000000,0x5C0739BA,0x3E47574C
405 data4 0x00005D18,0x3F3A2E88,0x3EA30C68,0x00000000,0x13E8AF2F,0x3E20E30F
406 data4 0x0000590C,0x3F321640,0x3EB9CEC8,0x00000000,0xF2C630BD,0xBE42885B
407 data4 0x00005556,0x3F2AAAA8,0x3ECF9927,0x00000000,0x97E577C6,0x3E497F34
408 data4 0x000051EC,0x3F23D708,0x3EE47FC5,0x00000000,0xA6B0A5AB,0x3E3E6A6E
409 data4 0x00004EC5,0x3F1D89D8,0x3EF8947D,0x00000000,0xD328D9BE,0xBDF43E3C
410 data4 0x00004BDB,0x3F17B420,0x3F05F3A1,0x00000000,0x0ADB090A,0x3E4094C3
411 data4 0x00004925,0x3F124920,0x3F0F4303,0x00000000,0xFC1FE510,0xBE28FBB2
412 data4 0x0000469F,0x3F0D3DC8,0x3F183EBF,0x00000000,0x10FDE3FA,0x3E3A7895
413 data4 0x00004445,0x3F088888,0x3F20EC80,0x00000000,0x7CC8C98F,0x3E508CE5
414 data4 0x00004211,0x3F042108,0x3F29516A,0x00000000,0xA223106C,0xBE534874
415 ASM_SIZE_DIRECTIVE(Constants_Z_G_H_h1)
417 // Z2 - 16 bit fixed, G2 and H2 - IEEE single
421 ASM_TYPE_DIRECTIVE(Constants_Z_G_H_h2,@object)
422 data4 0x00008000,0x3F800000,0x00000000,0x00000000,0x00000000,0x00000000
423 data4 0x00007F81,0x3F7F00F8,0x3B7F875D,0x00000000,0x22C42273,0x3DB5A116
424 data4 0x00007F02,0x3F7E03F8,0x3BFF015B,0x00000000,0x21F86ED3,0x3DE620CF
425 data4 0x00007E85,0x3F7D08E0,0x3C3EE393,0x00000000,0x484F34ED,0xBDAFA07E
426 data4 0x00007E08,0x3F7C0FC0,0x3C7E0586,0x00000000,0x3860BCF6,0xBDFE07F0
427 data4 0x00007D8D,0x3F7B1880,0x3C9E75D2,0x00000000,0xA78093D6,0x3DEA370F
428 data4 0x00007D12,0x3F7A2328,0x3CBDC97A,0x00000000,0x72A753D0,0x3DFF5791
429 data4 0x00007C98,0x3F792FB0,0x3CDCFE47,0x00000000,0xA7EF896B,0x3DFEBE6C
430 data4 0x00007C20,0x3F783E08,0x3CFC15D0,0x00000000,0x409ECB43,0x3E0CF156
431 data4 0x00007BA8,0x3F774E38,0x3D0D874D,0x00000000,0xFFEF71DF,0xBE0B6F97
432 data4 0x00007B31,0x3F766038,0x3D1CF49B,0x00000000,0x5D59EEE8,0xBE080483
433 data4 0x00007ABB,0x3F757400,0x3D2C531D,0x00000000,0xA9192A74,0x3E1F91E9
434 data4 0x00007A45,0x3F748988,0x3D3BA322,0x00000000,0xBF72A8CD,0xBE139A06
435 data4 0x000079D1,0x3F73A0D0,0x3D4AE46F,0x00000000,0xF8FBA6CF,0x3E1D9202
436 data4 0x0000795D,0x3F72B9D0,0x3D5A1756,0x00000000,0xBA796223,0xBE1DCCC4
437 data4 0x000078EB,0x3F71D488,0x3D693B9D,0x00000000,0xB6B7C239,0xBE049391
438 ASM_SIZE_DIRECTIVE(Constants_Z_G_H_h2)
440 // G3 and H3 - IEEE single and h3 -IEEE double
444 ASM_TYPE_DIRECTIVE(Constants_Z_G_H_h3,@object)
445 data4 0x3F7FFC00,0x38800100,0x562224CD,0x3D355595
446 data4 0x3F7FF400,0x39400480,0x06136FF6,0x3D8200A2
447 data4 0x3F7FEC00,0x39A00640,0xE8DE9AF0,0x3DA4D68D
448 data4 0x3F7FE400,0x39E00C41,0xB10238DC,0xBD8B4291
449 data4 0x3F7FDC00,0x3A100A21,0x3B1952CA,0xBD89CCB8
450 data4 0x3F7FD400,0x3A300F22,0x1DC46826,0xBDB10707
451 data4 0x3F7FCC08,0x3A4FF51C,0xF43307DB,0x3DB6FCB9
452 data4 0x3F7FC408,0x3A6FFC1D,0x62DC7872,0xBD9B7C47
453 data4 0x3F7FBC10,0x3A87F20B,0x3F89154A,0xBDC3725E
454 data4 0x3F7FB410,0x3A97F68B,0x62B9D392,0xBD93519D
455 data4 0x3F7FAC18,0x3AA7EB86,0x0F21BD9D,0x3DC18441
456 data4 0x3F7FA420,0x3AB7E101,0x2245E0A6,0xBDA64B95
457 data4 0x3F7F9C20,0x3AC7E701,0xAABB34B8,0x3DB4B0EC
458 data4 0x3F7F9428,0x3AD7DD7B,0x6DC40A7E,0x3D992337
459 data4 0x3F7F8C30,0x3AE7D474,0x4F2083D3,0x3DC6E17B
460 data4 0x3F7F8438,0x3AF7CBED,0x811D4394,0x3DAE314B
461 data4 0x3F7F7C40,0x3B03E1F3,0xB08F2DB1,0xBDD46F21
462 data4 0x3F7F7448,0x3B0BDE2F,0x6D34522B,0xBDDC30A4
463 data4 0x3F7F6C50,0x3B13DAAA,0xB1F473DB,0x3DCB0070
464 data4 0x3F7F6458,0x3B1BD766,0x6AD282FD,0xBDD65DDC
465 data4 0x3F7F5C68,0x3B23CC5C,0xF153761A,0xBDCDAB83
466 data4 0x3F7F5470,0x3B2BC997,0x341D0F8F,0xBDDADA40
467 data4 0x3F7F4C78,0x3B33C711,0xEBC394E8,0x3DCD1BD7
468 data4 0x3F7F4488,0x3B3BBCC6,0x52E3E695,0xBDC3532B
469 data4 0x3F7F3C90,0x3B43BAC0,0xE846B3DE,0xBDA3961E
470 data4 0x3F7F34A0,0x3B4BB0F4,0x785778D4,0xBDDADF06
471 data4 0x3F7F2CA8,0x3B53AF6D,0xE55CE212,0x3DCC3ED1
472 data4 0x3F7F24B8,0x3B5BA620,0x9E382C15,0xBDBA3103
473 data4 0x3F7F1CC8,0x3B639D12,0x5C5AF197,0x3D635A0B
474 data4 0x3F7F14D8,0x3B6B9444,0x71D34EFC,0xBDDCCB19
475 data4 0x3F7F0CE0,0x3B7393BC,0x52CD7ADA,0x3DC74502
476 data4 0x3F7F04F0,0x3B7B8B6D,0x7D7F2A42,0xBDB68F17
477 ASM_SIZE_DIRECTIVE(Constants_Z_G_H_h3)
480 // Exponent Thresholds and Tiny Thresholds
481 // for 8, 11, 15, and 17 bit exponents
485 // 0 (8 bits) 2^(-126)
486 // 1 (11 bits) 2^(-1022)
487 // 2 (15 bits) 2^(-16382)
488 // 3 (17 bits) 2^(-16382)
494 // 0 (8 bits) 2^(-16382)
495 // 1 (11 bits) 2^(-16382)
496 // 2 (15 bits) 2^(-16382)
497 // 3 (17 bits) 2^(-16382)
502 ASM_TYPE_DIRECTIVE(Constants_Threshold,@object)
503 data4 0x00000000,0x80000000,0x00003F81,0x00000000
504 data4 0x00000000,0x80000000,0x00000001,0x00000000
505 data4 0x00000000,0x80000000,0x00003C01,0x00000000
506 data4 0x00000000,0x80000000,0x00000001,0x00000000
507 data4 0x00000000,0x80000000,0x00000001,0x00000000
508 data4 0x00000000,0x80000000,0x00000001,0x00000000
509 data4 0x00000000,0x80000000,0x00000001,0x00000000
510 data4 0x00000000,0x80000000,0x00000001,0x00000000
511 ASM_SIZE_DIRECTIVE(Constants_Threshold)
515 ASM_TYPE_DIRECTIVE(Constants_1_by_LN10,@object)
516 data4 0x37287195,0xDE5BD8A9,0x00003FFD,0x00000000
517 data4 0xACCF70C8,0xD56EAABE,0x00003FBB,0x00000000
518 ASM_SIZE_DIRECTIVE(Constants_1_by_LN10)
593 FR_Output_X_tmp = f99
615 // Added for unwind support
623 GR_Parameter_RESULT = r56
624 GR_Parameter_TAG = r57
636 .global __ieee754_logl
640 alloc r32 = ar.pfs,0,22,4,0
641 (p0) fnorm.s1 FR_X_Prime = FR_Input_X
642 (p0) cmp.eq.unc p7, p0 = r0, r0
645 (p0) cmp.ne.unc p14, p0 = r0, r0
646 (p0) fclass.m.unc p6, p0 = FR_Input_X, 0x1E3
647 (p0) cmp.ne.unc p15, p0 = r0, r0 ;;
651 (p0) fclass.nm.unc p10, p0 = FR_Input_X, 0x1FF
656 (p0) fcmp.eq.unc.s1 p8, p0 = FR_Input_X, f0
661 (p0) fcmp.lt.unc.s1 p13, p0 = FR_Input_X, f0
666 (p0) fcmp.eq.unc.s1 p9, p0 = FR_Input_X, f1
671 (p0) fsub.s1 FR_Em1 = f0,f1
676 (p0) fadd FR_E = f0,f0
678 // Create E = 0 and Em1 = -1
679 // Check for X == 1, meaning logl(1)
680 // Check for X < 0, meaning logl(negative)
681 // Check for X == 0, meaning logl(0)
682 // Identify NatVals, NaNs, Infs.
683 // Identify EM unsupporteds.
684 // Identify Negative values - us S1 so as
685 // not to raise denormal operand exception
686 // Set p15 to false for log
687 // Set p14 to false for log
688 // Set p7 true for log and log1p
690 (p0) br.cond.sptk L(LOGL_BEGIN) ;;
694 ASM_SIZE_DIRECTIVE(logl)
702 .global __ieee754_log10l
706 alloc r32 = ar.pfs,0,22,4,0
707 (p0) fadd FR_E = f0,f0
712 (p0) fsub.s1 FR_Em1 = f0,f1
716 (p0) cmp.ne.unc p15, p0 = r0, r0
717 (p0) fcmp.eq.unc.s1 p9, p0 = FR_Input_X, f1
721 (p0) cmp.eq.unc p14, p0 = r0, r0
722 (p0) fcmp.lt.unc.s1 p13, p0 = FR_Input_X, f0
723 (p0) cmp.ne.unc p7, p0 = r0, r0 ;;
727 (p0) fcmp.eq.unc.s1 p8, p0 = FR_Input_X, f0
732 (p0) fclass.nm.unc p10, p0 = FR_Input_X, 0x1FF
737 (p0) fclass.m.unc p6, p0 = FR_Input_X, 0x1E3
742 (p0) fnorm.s1 FR_X_Prime = FR_Input_X
744 // Create E = 0 and Em1 = -1
745 // Check for X == 1, meaning logl(1)
746 // Check for X < 0, meaning logl(negative)
747 // Check for X == 0, meaning logl(0)
748 // Identify NatVals, NaNs, Infs.
749 // Identify EM unsupporteds.
750 // Identify Negative values - us S1 so as
751 // Identify Negative values - us S1 so as
752 // not to raise denormal operand exception
753 // Set p15 to false for log10
754 // Set p14 to true for log10
755 // Set p7 to false for log10
757 (p0) br.cond.sptk L(LOGL_BEGIN) ;;
761 ASM_SIZE_DIRECTIVE(log10l)
773 alloc r32 = ar.pfs,0,22,4,0
774 (p0) fsub.s1 FR_Neg_One = f0,f1
775 (p0) cmp.eq.unc p7, p0 = r0, r0
778 (p0) cmp.ne.unc p14, p0 = r0, r0
779 (p0) fnorm.s1 FR_X_Prime = FR_Input_X
780 (p0) cmp.eq.unc p15, p0 = r0, r0 ;;
784 (p0) fclass.m.unc p6, p0 = FR_Input_X, 0x1E3
789 (p0) fclass.nm.unc p10, p0 = FR_Input_X, 0x1FF
794 (p0) fcmp.eq.unc.s1 p9, p0 = FR_Input_X, f0
799 (p0) fadd FR_Em1 = f0,f0
804 (p0) fadd FR_E = f0,f1
809 (p0) fcmp.eq.unc.s1 p8, p0 = FR_Input_X, FR_Neg_One
814 (p0) fcmp.lt.unc.s1 p13, p0 = FR_Input_X, FR_Neg_One
820 (p0) fadd.s1 FR_Z = FR_X_Prime, FR_E
825 (p0) movl GR_Table_Scale = 0x0000000000000018 ;;
831 // Create E = 1 and Em1 = 0
832 // Check for X == 0, meaning logl(1+0)
833 // Check for X < -1, meaning logl(negative)
834 // Check for X == -1, meaning logl(0)
836 // Identify NatVals, NaNs, Infs.
837 // Identify EM unsupporteds.
838 // Identify Negative values - us S1 so as
839 // not to raise denormal operand exception
840 // Set p15 to true for log1p
841 // Set p14 to false for log1p
842 // Set p7 true for log and log1p
844 (p0) addl GR_Table_Base = @ltoff(Constants_Z_G_H_h1#),gp
848 (p0) fmax.s1 FR_AA = FR_X_Prime, FR_E
852 ld8 GR_Table_Base = [GR_Table_Base]
853 (p0) fmin.s1 FR_BB = FR_X_Prime, FR_E
858 (p0) fadd.s1 FR_W = FR_X_Prime, FR_Em1
860 // Begin load of constants base
861 // FR_Z = Z = |x| + E
862 // FR_W = W = |x| + Em1
866 (p6) br.cond.spnt L(LOGL_64_special) ;;
871 (p10) br.cond.spnt L(LOGL_64_unsupported) ;;
876 (p13) br.cond.spnt L(LOGL_64_negative) ;;
879 (p0) getf.sig GR_signif = FR_Z
881 (p9) br.cond.spnt L(LOGL_64_one) ;;
886 (p8) br.cond.spnt L(LOGL_64_zero) ;;
889 (p0) getf.exp GR_N = FR_Z
891 // Raise possible denormal operand exception
894 // This function computes ln( x + e )
895 // Input FR 1: FR_X = FR_Input_X
896 // Input FR 2: FR_E = FR_E
897 // Input FR 3: FR_Em1 = FR_Em1
898 // Input GR 1: GR_Expo_Range = GR_Expo_Range = 1
899 // Output FR 4: FR_Y_hi
900 // Output FR 5: FR_Y_lo
901 // Output FR 6: FR_Scale
902 // Output PR 7: PR_Safe
904 (p0) fsub.s1 FR_S_lo = FR_AA, FR_Z
906 // signif = getf.sig(Z)
909 (p0) extr.u GR_Table_ptr = GR_signif, 59, 4 ;;
913 (p0) fmerge.se FR_S_hi = f1,FR_Z
914 (p0) extr.u GR_X_0 = GR_signif, 49, 15
919 (p0) addl GR_Table_Base1 = @ltoff(Constants_Z_G_H_h2#),gp ;;
922 ld8 GR_Table_Base1 = [GR_Table_Base1]
923 (p0) movl GR_Bias = 0x000000000000FFFF ;;
927 (p0) fabs FR_abs_W = FR_W
928 (p0) pmpyshr2.u GR_Table_ptr = GR_Table_ptr,GR_Table_Scale,0
933 // Branch out for special input values
935 (p0) fcmp.lt.unc.s0 p8, p0 = FR_Input_X, f0
941 // X_0 = extr.u(signif,49,15)
942 // Index1 = extr.u(signif,59,4)
944 (p0) fadd.s1 FR_S_lo = FR_S_lo, FR_BB
951 // Offset_to_Z1 = 24 * Index1
952 // For performance, don't use result
953 // for 3 or 4 cycles.
955 (p0) add GR_Table_ptr = GR_Table_ptr, GR_Table_Base ;;
958 // Add Base to Offset for Z1
961 (p0) ld4 GR_Z_1 = [GR_Table_ptr],4 ;;
962 (p0) ldfs FR_G = [GR_Table_ptr],4
966 (p0) ldfs FR_H = [GR_Table_ptr],8 ;;
967 (p0) ldfd FR_h = [GR_Table_ptr],0
968 (p0) pmpyshr2.u GR_X_1 = GR_X_0,GR_Z_1,15
972 // Get Base of Table2
975 (p0) getf.exp GR_M = FR_abs_W
983 // M = getf.exp(abs_W)
985 // X_1 = pmpyshr2(X_0,Z_1,15)
987 (p0) sub GR_M = GR_M, GR_Bias ;;
995 (p0) cmp.gt.unc p11, p0 = -80, GR_M
996 (p0) cmp.gt.unc p12, p0 = -7, GR_M ;;
997 (p0) extr.u GR_Index2 = GR_X_1, 6, 4 ;;
1002 // if -80 > M, set p11
1003 // Index2 = extr.u(X_1,6,4)
1004 // if -7 > M, set p12
1007 (p0) pmpyshr2.u GR_Index2 = GR_Index2,GR_Table_Scale,0
1008 (p11) br.cond.spnt L(log1pl_small) ;;
1013 (p12) br.cond.spnt L(log1pl_near) ;;
1016 (p0) sub GR_N = GR_N, GR_Bias
1018 // poly_lo = r * poly_lo
1020 (p0) add GR_Perturb = 0x1, r0 ;;
1021 (p0) sub GR_ScaleN = GR_Bias, GR_N
1024 (p0) setf.sig FR_float_N = GR_N
1027 // Prepare Index2 - pmpyshr2.u(X_1,Z_2,15)
1030 // Branch for -80 > M
1032 (p0) add GR_Index2 = GR_Index2, GR_Table_Base1
1035 (p0) setf.exp FR_two_negN = GR_ScaleN
1037 (p0) addl GR_Table_Base = @ltoff(Constants_Z_G_H_h3#),gp ;;
1040 // Index2 points to Z2
1041 // Branch for -7 > M
1044 (p0) ld4 GR_Z_2 = [GR_Index2],4
1045 (p0) ld8 GR_Table_Base = [GR_Table_Base]
1052 // Tablebase points to Table3
1055 (p0) ldfs FR_G_tmp = [GR_Index2],4 ;;
1058 // pmpyshr2 X_2= (X_1,Z_2,15)
1059 // float_N = setf.sig(N)
1060 // ScaleN = Bias - N
1062 (p0) ldfs FR_H_tmp = [GR_Index2],8
1067 // two_negN = setf.exp(scaleN)
1071 (p0) ldfd FR_h_tmp = [GR_Index2],0
1073 (p0) pmpyshr2.u GR_X_2 = GR_X_1,GR_Z_2,15 ;;
1077 (p0) extr.u GR_Index3 = GR_X_2, 1, 5 ;;
1082 // Index3 = extr.u(X_2,1,5)
1084 (p0) shladd GR_Index3 = GR_Index3,4,GR_Table_Base
1090 // float_N = fcvt.xf(float_N)
1093 (p0) addl GR_Table_Base = @ltoff(Constants_Q#),gp ;;
1097 ld8 GR_Table_Base = [GR_Table_Base]
1102 (p0) ldfe FR_log2_hi = [GR_Table_Base],16
1103 (p0) fmpy.s1 FR_S_lo = FR_S_lo, FR_two_negN
1114 (p0) ldfe FR_log2_lo = [GR_Table_Base],16
1115 (p0) fmpy.s1 FR_G = FR_G, FR_G_tmp ;;
1118 (p0) ldfs FR_G_tmp = [GR_Index3],4
1124 (p0) ldfe FR_Q4 = [GR_Table_Base],16
1125 (p0) fadd.s1 FR_h = FR_h, FR_h_tmp ;;
1128 (p0) ldfe FR_Q3 = [GR_Table_Base],16
1129 (p0) fadd.s1 FR_H = FR_H, FR_H_tmp
1133 (p0) ldfs FR_H_tmp = [GR_Index3],4
1134 (p0) ldfe FR_Q2 = [GR_Table_Base],16
1136 // Comput Index for Table3
1137 // S_lo = S_lo * two_negN
1139 (p0) fcvt.xf FR_float_N = FR_float_N ;;
1142 // If S_lo == 0, set p8 false
1144 // Load ptr to table of polynomial coeff.
1147 (p0) ldfd FR_h_tmp = [GR_Index3],0
1148 (p0) ldfe FR_Q1 = [GR_Table_Base],0
1149 (p0) fcmp.eq.unc.s1 p0, p8 = FR_S_lo, f0 ;;
1153 (p0) fmpy.s1 FR_G = FR_G, FR_G_tmp
1158 (p0) fadd.s1 FR_H = FR_H, FR_H_tmp
1163 (p0) fms.s1 FR_r = FR_G, FR_S_hi, f1
1168 (p0) fadd.s1 FR_h = FR_h, FR_h_tmp
1173 (p0) fma.s1 FR_Y_hi = FR_float_N, FR_log2_hi, FR_H
1184 (p8) fma.s1 FR_r = FR_G, FR_S_lo, FR_r
1190 // poly_lo = r * Q4 + Q3
1193 (p0) fma.s1 FR_h = FR_float_N, FR_log2_lo, FR_h
1199 // If (S_lo!=0) r = s_lo * G + r
1201 (p0) fma.s1 FR_poly_lo = FR_r, FR_Q4, FR_Q3
1205 // Create a 0x00000....01
1206 // poly_lo = poly_lo * rsq + h
1209 (p0) setf.sig FR_dummy = GR_Perturb
1210 (p0) fmpy.s1 FR_rsq = FR_r, FR_r
1216 // h = N * log2_lo + h
1217 // Y_hi = n * log2_hi + H
1219 (p0) fma.s1 FR_poly_lo = FR_poly_lo, FR_r, FR_Q2
1224 (p0) fma.s1 FR_poly_hi = FR_Q1, FR_rsq, FR_r
1230 // poly_lo = r * poly_o + Q2
1231 // poly_hi = Q1 * rsq + r
1233 (p0) fmpy.s1 FR_poly_lo = FR_poly_lo, FR_r
1238 (p0) fma.s1 FR_poly_lo = FR_poly_lo, FR_rsq, FR_h
1243 (p0) fadd.s1 FR_Y_lo = FR_poly_hi, FR_poly_lo
1245 // Create the FR for a binary "or"
1246 // Y_lo = poly_hi + poly_lo
1248 // (p0) for FR_dummy = FR_Y_lo,FR_dummy ;;
1250 // Turn the lsb of Y_lo ON
1252 // (p0) fmerge.se FR_Y_lo = FR_Y_lo,FR_dummy ;;
1254 // Merge the new lsb into Y_lo, for alone doesn't
1256 (p0) br.cond.sptk LOGL_main ;;
1262 // /*******************************************************/
1263 // /*********** Branch log1pl_near ************************/
1264 // /*******************************************************/
1265 (p0) addl GR_Table_Base = @ltoff(Constants_P#),gp ;;
1269 ld8 GR_Table_Base = [GR_Table_Base]
1273 // Load base address of poly. coeff.
1276 (p0) add GR_Table_ptr = 0x40,GR_Table_Base
1278 // Address tables with separate pointers
1280 (p0) ldfe FR_P8 = [GR_Table_Base],16
1284 (p0) ldfe FR_P4 = [GR_Table_ptr],16
1289 (p0) ldfe FR_P7 = [GR_Table_Base],16
1293 (p0) ldfe FR_P3 = [GR_Table_ptr],16
1298 (p0) ldfe FR_P6 = [GR_Table_Base],16
1299 (p0) fmpy.s1 FR_wsq = FR_W, FR_W ;;
1302 (p0) ldfe FR_P2 = [GR_Table_ptr],16
1308 (p0) fma.s1 FR_Y_hi = FR_W, FR_P4, FR_P3
1315 // Y_hi = p4 * w + p3
1318 (p0) ldfe FR_P5 = [GR_Table_Base],16
1319 (p0) fma.s1 FR_Y_lo = FR_W, FR_P8, FR_P7
1323 (p0) ldfe FR_P1 = [GR_Table_ptr],16
1327 // Y_lo = p8 * w + P7
1329 (p0) fmpy.s1 FR_w4 = FR_wsq, FR_wsq
1334 (p0) fma.s1 FR_Y_hi = FR_W, FR_Y_hi, FR_P2
1339 (p0) fma.s1 FR_Y_lo = FR_W, FR_Y_lo, FR_P6
1340 (p0) add GR_Perturb = 0x1, r0 ;;
1346 // Y_hi = y_hi * w + p2
1347 // Y_lo = y_lo * w + p6
1348 // Create perturbation bit
1350 (p0) fmpy.s1 FR_w6 = FR_w4, FR_wsq
1355 (p0) fma.s1 FR_Y_hi = FR_W, FR_Y_hi, FR_P1
1359 // Y_hi = y_hi * w + p1
1363 (p0) setf.sig FR_Q4 = GR_Perturb
1364 (p0) fma.s1 FR_Y_lo = FR_W, FR_Y_lo, FR_P5
1369 (p0) fma.s1 FR_dummy = FR_wsq,FR_Y_hi, f0
1374 (p0) fma.s1 FR_Y_hi = FR_W,f1,f0
1381 // Y_lo = y_lo * w + p5
1383 (p0) fma.s1 FR_Y_lo = FR_w6, FR_Y_lo,FR_dummy
1385 // Y_lo = y_lo * w6 + y_high order part.
1389 (p0) br.cond.sptk LOGL_main ;;
1394 // /*******************************************************/
1395 // /*********** Branch log1pl_small ***********************/
1396 // /*******************************************************/
1397 (p0) addl GR_Table_Base = @ltoff(Constants_Threshold#),gp
1401 (p0) mov FR_Em1 = FR_W
1402 (p0) cmp.eq.unc p7, p0 = r0, r0 ;;
1405 ld8 GR_Table_Base = [GR_Table_Base]
1406 (p0) movl GR_Expo_Range = 0x0000000000000004 ;;
1410 // Set Expo_Range = 0 for single
1411 // Set Expo_Range = 2 for double
1412 // Set Expo_Range = 4 for double-extended
1415 (p0) shladd GR_Table_Base = GR_Expo_Range,4,GR_Table_Base ;;
1416 (p0) ldfe FR_Threshold = [GR_Table_Base],16
1421 (p0) movl GR_Bias = 0x000000000000FF9B ;;
1424 (p0) ldfe FR_Tiny = [GR_Table_Base],0
1430 (p0) fcmp.gt.unc.s1 p13, p12 = FR_abs_W, FR_Threshold
1435 (p13) fnmpy.s1 FR_Y_lo = FR_W, FR_W
1440 (p13) fadd FR_SCALE = f0, f1
1445 (p12) fsub.s1 FR_Y_lo = f0, FR_Tiny
1446 (p12) cmp.ne.unc p7, p0 = r0, r0
1449 (p12) setf.exp FR_SCALE = GR_Bias
1456 // Set p7 to SAFE = FALSE
1457 // Set Scale = 2^-100
1459 (p0) fma.s0 f8 = FR_Y_lo,FR_SCALE,FR_Y_hi
1460 (p0) br.ret.sptk b0 ;;
1465 (p0) fmpy.s0 f8 = FR_Input_X, f0
1466 (p0) br.ret.sptk b0 ;;
1469 // Raise divide by zero for +/-0 input.
1473 (p0) mov GR_Parameter_TAG = 0
1475 // If we have logl(1), log10l(1) or log1pl(0), return 0.
1477 (p0) fsub.s0 FR_Output_X_tmp = f0, f1
1481 (p14) mov GR_Parameter_TAG = 6
1483 (p15) mov GR_Parameter_TAG = 138 ;;
1487 (p0) frcpa.s0 FR_Output_X_tmp, p8 = FR_Output_X_tmp, f0
1488 (p0) br.cond.sptk __libm_error_region ;;
1493 // Report that logl(0) computed
1495 (p0) mov FR_Input_X = FR_Output_X_tmp
1496 (p0) br.ret.sptk b0 ;;
1503 // Return -Inf or value from handler.
1505 (p0) fclass.m.unc p7, p0 = FR_Input_X, 0x1E1
1511 // Check for Natval, QNan, SNaN, +Inf
1513 (p7) fmpy.s0 f8 = FR_Input_X, f1
1515 // For SNaN raise invalid and return QNaN.
1516 // For QNaN raise invalid and return QNaN.
1517 // For +Inf return +Inf.
1519 (p7) br.ret.sptk b0 ;;
1522 // For -Inf raise invalid and return QNaN.
1525 (p0) mov GR_Parameter_TAG = 1
1527 (p14) mov GR_Parameter_TAG = 7 ;;
1530 (p15) mov GR_Parameter_TAG = 139
1536 (p0) fmpy.s0 FR_Output_X_tmp = FR_Input_X, f0
1537 (p0) br.cond.sptk __libm_error_region ;;
1540 // Report that logl(-Inf) computed
1541 // Report that log10l(-Inf) computed
1542 // Report that log1p(-Inf) computed
1546 (p0) mov FR_Input_X = FR_Output_X_tmp
1547 (p0) br.ret.sptk b0 ;;
1549 L(LOGL_64_unsupported):
1553 // Return generated NaN or other value .
1555 (p0) fmpy.s0 f8 = FR_Input_X, f0
1556 (p0) br.ret.sptk b0 ;;
1558 L(LOGL_64_negative):
1562 // Deal with x < 0 in a special way
1564 (p0) frcpa.s0 FR_Output_X_tmp, p8 = f0, f0
1566 // Deal with x < 0 in a special way - raise
1567 // invalid and produce QNaN indefinite.
1569 (p0) mov GR_Parameter_TAG = 1 ;;
1572 (p14) mov GR_Parameter_TAG = 7
1574 (p15) mov GR_Parameter_TAG = 139
1577 ASM_SIZE_DIRECTIVE(log1pl)
1579 .proc __libm_error_region
1580 __libm_error_region:
1583 add GR_Parameter_Y=-32,sp // Parameter 2 value
1585 .save ar.pfs,GR_SAVE_PFS
1586 mov GR_SAVE_PFS=ar.pfs // Save ar.pfs
1590 add sp=-64,sp // Create new stack
1592 mov GR_SAVE_GP=gp // Save gp
1595 stfe [GR_Parameter_Y] = FR_Y,16 // Save Parameter 2 on stack
1596 add GR_Parameter_X = 16,sp // Parameter 1 address
1597 .save b0, GR_SAVE_B0
1598 mov GR_SAVE_B0=b0 // Save b0
1602 stfe [GR_Parameter_X] = FR_X // Store Parameter 1 on stack
1603 add GR_Parameter_RESULT = 0,GR_Parameter_Y
1604 nop.b 0 // Parameter 3 address
1607 stfe [GR_Parameter_Y] = FR_RESULT // Store Parameter 3 on stack
1608 add GR_Parameter_Y = -16,GR_Parameter_Y
1609 br.call.sptk b0=__libm_error_support# // Call error handling function
1614 add GR_Parameter_RESULT = 48,sp
1617 ldfe f8 = [GR_Parameter_RESULT] // Get return result off stack
1619 add sp = 64,sp // Restore stack pointer
1620 mov b0 = GR_SAVE_B0 // Restore return address
1623 mov gp = GR_SAVE_GP // Restore gp
1624 mov ar.pfs = GR_SAVE_PFS // Restore ar.pfs
1625 br.ret.sptk b0 // Return
1628 .endp __libm_error_region
1629 ASM_SIZE_DIRECTIVE(__libm_error_region)
1636 // kernel_log_64 computes ln(X + E)
1638 (p7) fadd.s0 FR_Input_X = FR_Y_lo,FR_Y_hi
1644 (p14) addl GR_Table_Base = @ltoff(Constants_1_by_LN10#),gp ;;
1648 (p14) ld8 GR_Table_Base = [GR_Table_Base]
1653 (p14) ldfe FR_1LN10_hi = [GR_Table_Base],16 ;;
1654 (p14) ldfe FR_1LN10_lo = [GR_Table_Base]
1659 (p14) fmpy.s1 FR_Output_X_tmp = FR_Y_lo,FR_1LN10_hi
1664 (p14) fma.s1 FR_Output_X_tmp = FR_Y_hi,FR_1LN10_lo,FR_Output_X_tmp
1669 (p14) fma.s0 FR_Input_X = FR_Y_hi,FR_1LN10_hi,FR_Output_X_tmp
1670 (p0) br.ret.sptk b0 ;;
1673 ASM_SIZE_DIRECTIVE(LOGL_main)
1675 .type __libm_error_support#,@function
1676 .global __libm_error_support#