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* sysdeps/ia64/fpu/e_acosh.S: Update from Intel libm 2005-04-05
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1.file "exp2f.s"
2
3
cd1fe198 4// Copyright (c) 2000 - 2005, Intel Corporation
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5// All rights reserved.
6//
7// Contributed 2000 by the Intel Numerics Group, Intel Corporation
8//
9// Redistribution and use in source and binary forms, with or without
10// modification, are permitted provided that the following conditions are
11// met:
12//
13// * Redistributions of source code must retain the above copyright
14// notice, this list of conditions and the following disclaimer.
15//
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.
19//
20// * The name of Intel Corporation may not be used to endorse or promote
21// products derived from this software without specific prior written
22// permission.
23
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.
35//
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
ee618985 38// http://www.intel.com/software/products/opensource/libraries/num.htm.
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39//
40// History
41//==============================================================
42// 08/25/00 Initial version
43// 05/20/02 Cleaned up namespace and sf0 syntax
44// 09/05/02 Improved performance and accuracy
45// 01/17/03 Fixed to call error support when x=128.0
cd1fe198 46// 03/31/05 Reformatted delimiters between data tables
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47//
48// API
49//==============================================================
50// float exp2f(float)
51//
52// Overview of operation
53//==============================================================
54// Background
55//
56// Implementation
57//
58// Let x= (K + fh + fl + r), where
59// K is an integer, fh= 0.b1 b2 b3 b4 b5,
60// fl= 2^{-5}* 0.b6 b7 b8 b8 b10 (fh, fl >= 0),
61// and |r|<2^{-11}
62// Th is a table that stores 2^fh (32 entries) rounded to
63// double extended precision (only mantissa is stored)
64// Tl is a table that stores 2^fl (32 entries) rounded to
65// double extended precision (only mantissa is stored)
66//
67// 2^x is approximated as
68// 2^K * Th [ f ] * Tl [ f ] * (1+c1*r+c2*r^2)
69
70// Note: We use the following trick to speed up conversion from FP to integer:
71//
72// Let x = K + r, where K is an integer, and |r| <= 0.5
73// Let N be the number of significand bits for the FP format used
74// ( N=64 for double-extended, N=53 for double)
75//
76// Then let y = 1.5 * 2^(N-1) + x for RN mode
77// K = y - 1.5 * 2^(N-1)
78// r = x - K
79//
80// If we want to obtain the integer part and the first m fractional bits of x,
81// we can use the same trick, but with a constant of 1.5 * 2^(N-1-m):
82//
83// Let x = K + f + r
84// f = 0.b_1 b_2 ... b_m
85// |r| <= 2^(-m-1)
86//
87// Then let y = 1.5 * 2^(N-1-m) + x for RN mode
88// (K+f) = y - 1.5 * 2^(N-1-m)
89// r = x - K
90
91
92// Special values
93//==============================================================
94// exp2(0)= 1
95// exp2(+inf)= inf
96// exp2(-inf)= 0
97//
98
99// Registers used
100//==============================================================
101// r2-r3, r14-r40
102// f6-f15, f32-f45
103// p6-p8, p12
104//
105
106
107GR_TBL_START = r2
108GR_LOG_TBL = r3
109
110GR_OF_LIMIT = r14
111GR_UF_LIMIT = r15
112GR_EXP_CORR = r16
113GR_F_low = r17
114GR_F_high = r18
115GR_K = r19
116GR_Flow_ADDR = r20
117
118GR_BIAS = r21
119GR_Fh = r22
120GR_Fh_ADDR = r23
121GR_EXPMAX = r24
122GR_EMIN = r25
123
124GR_ROUNDVAL = r26
125GR_MASK = r27
126GR_KF0 = r28
127GR_MASK_low = r29
128GR_COEFF_START = r30
129
130GR_SAVE_B0 = r33
131GR_SAVE_PFS = r34
132GR_SAVE_GP = r35
133GR_SAVE_SP = r36
134
135GR_Parameter_X = r37
136GR_Parameter_Y = r38
137GR_Parameter_RESULT = r39
138GR_Parameter_TAG = r40
139
140
141FR_X = f10
142FR_Y = f1
143FR_RESULT = f8
144
145
146FR_COEFF1 = f6
147FR_COEFF2 = f7
148FR_R = f9
149
150FR_KF0 = f12
151FR_UF_LIMIT = f15
152
153FR_OF_LIMIT = f32
154FR_EXPMIN = f33
155FR_ROUNDVAL = f34
156FR_KF = f35
157
158FR_2_TO_K = f36
159FR_T_low = f37
160FR_T_high = f38
161
162FR_P12 = f41
163FR_T_low_K = f42
164FR_T = f44
165FR_P = f45
166
167
168// Data tables
169//==============================================================
170
171RODATA
172
173.align 16
174
175LOCAL_OBJECT_START(poly_coeffs)
176
177data8 0xb17217f7d1cf79ab, 0x00003ffe // C_1
178data8 0xf5fdeffc162c7541, 0x00003ffc // C_2
179LOCAL_OBJECT_END(poly_coeffs)
180
181
182LOCAL_OBJECT_START(T_table)
183
184// 2^{0.00000 b6 b7 b8 b9 b10}
185data8 0x8000000000000000, 0x8016302f17467628
186data8 0x802c6436d0e04f50, 0x80429c17d77c18ed
187data8 0x8058d7d2d5e5f6b0, 0x806f17687707a7af
188data8 0x80855ad965e88b83, 0x809ba2264dada76a
189data8 0x80b1ed4fd999ab6c, 0x80c83c56b50cf77f
190data8 0x80de8f3b8b85a0af, 0x80f4e5ff089f763e
191data8 0x810b40a1d81406d4, 0x81219f24a5baa59d
192data8 0x813801881d886f7b, 0x814e67cceb90502c
193data8 0x8164d1f3bc030773, 0x817b3ffd3b2f2e47
194data8 0x8191b1ea15813bfd, 0x81a827baf7838b78
195data8 0x81bea1708dde6055, 0x81d51f0b8557ec1c
196data8 0x81eba08c8ad4536f, 0x820225f44b55b33b
197data8 0x8218af4373fc25eb, 0x822f3c7ab205c89a
198data8 0x8245cd9ab2cec048, 0x825c62a423d13f0c
199data8 0x8272fb97b2a5894c, 0x828998760d01faf3
200data8 0x82a0393fe0bb0ca8, 0x82b6ddf5dbc35906
201//
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202// 2^{0.b1 b2 b3 b4 b5}
203data8 0x8000000000000000, 0x82cd8698ac2ba1d7
204data8 0x85aac367cc487b14, 0x88980e8092da8527
205data8 0x8b95c1e3ea8bd6e6, 0x8ea4398b45cd53c0
206data8 0x91c3d373ab11c336, 0x94f4efa8fef70961
207data8 0x9837f0518db8a96f, 0x9b8d39b9d54e5538
208data8 0x9ef5326091a111ad, 0xa27043030c496818
209data8 0xa5fed6a9b15138ea, 0xa9a15ab4ea7c0ef8
210data8 0xad583eea42a14ac6, 0xb123f581d2ac258f
211data8 0xb504f333f9de6484, 0xb8fbaf4762fb9ee9
212data8 0xbd08a39f580c36be, 0xc12c4cca66709456
213data8 0xc5672a115506dadd, 0xc9b9bd866e2f27a2
214data8 0xce248c151f8480e3, 0xd2a81d91f12ae45a
215data8 0xd744fccad69d6af4, 0xdbfbb797daf23755
216data8 0xe0ccdeec2a94e111, 0xe5b906e77c8348a8
217data8 0xeac0c6e7dd24392e, 0xefe4b99bdcdaf5cb
218data8 0xf5257d152486cc2c, 0xfa83b2db722a033a
219LOCAL_OBJECT_END(T_table)
220
221
222
223.section .text
224GLOBAL_LIBM_ENTRY(exp2f)
225
226
227{.mfi
228 alloc r32= ar.pfs, 1, 4, 4, 0
229 // will continue only for non-zero normal/denormal numbers
230 fclass.nm p12, p0= f8, 0x1b
231 // GR_TBL_START= pointer to C_1...C_2 followed by T_table
232 addl GR_TBL_START= @ltoff(poly_coeffs), gp
233}
234{.mlx
235 mov GR_OF_LIMIT= 0xffff + 7 // Exponent of overflow limit
236 movl GR_ROUNDVAL= 0x5a400000 // 1.5*2^(63-10) (SP)
237}
238;;
239
240// Form special constant 1.5*2^(63-10) to give integer part and first 10
241// fractional bits of x
242{.mfi
243 setf.s FR_ROUNDVAL= GR_ROUNDVAL // Form special constant
244 fcmp.lt.s1 p6, p8= f8, f0 // X<0 ?
245 nop.i 0
246}
247{.mfb
248 ld8 GR_COEFF_START= [ GR_TBL_START ] // Load pointer to coeff table
249 nop.f 0
250 (p12) br.cond.spnt SPECIAL_exp2 // Branch if nan, inf, zero
251}
252;;
253
254{.mlx
255 setf.exp FR_OF_LIMIT= GR_OF_LIMIT // Set overflow limit
256 movl GR_UF_LIMIT= 0xc3160000 // (-2^7-22) = -150
257}
258;;
259
260{.mfi
261 ldfe FR_COEFF1= [ GR_COEFF_START ], 16 // load C_1
262 fma.s0 f8= f8, f1, f0 // normalize x
263 nop.i 0
264}
265;;
266
267{.mmi
268 ldfe FR_COEFF2= [ GR_COEFF_START ], 16 // load C_2
269 setf.s FR_UF_LIMIT= GR_UF_LIMIT // Set underflow limit
270 mov GR_EXP_CORR= 0xffff-126
271}
272;;
273
274{.mfi
275 nop.m 0
276 fma.s1 FR_KF0= f8, f1, FR_ROUNDVAL // y= x + 1.5*2^(63-10)
277 nop.i 0
278}
279;;
280
281{.mfi
282 mov GR_MASK= 1023
283 fms.s1 FR_KF= FR_KF0, f1, FR_ROUNDVAL // (K+f)
284 mov GR_MASK_low= 31
285}
286;;
287
288{.mfi
289 getf.sig GR_KF0= FR_KF0 // (K+f)*2^10= round_to_int(y)
290 fcmp.ge.s1 p12, p7= f8, FR_OF_LIMIT // x >= overflow threshold ?
291 add GR_LOG_TBL= 256, GR_COEFF_START // Pointer to high T_table
292}
293;;
294
295{.mmi
296 and GR_F_low= GR_KF0, GR_MASK_low // f_low
297 and GR_F_high= GR_MASK, GR_KF0 // f_high*32
298 shr GR_K= GR_KF0, 10 // K
299}
300;;
301
302{.mmi
303 shladd GR_Flow_ADDR= GR_F_low, 3, GR_COEFF_START // address of 2^{f_low}
304 add GR_BIAS= GR_K, GR_EXP_CORR // K= bias-2*63
305 shr GR_Fh= GR_F_high, 5 // f_high
306}
307;;
308
309{.mfi
310 setf.exp FR_2_TO_K= GR_BIAS // 2^{K-126}
311 fnma.s1 FR_R= FR_KF, f1, f8 // r= x - (K+f)
312 shladd GR_Fh_ADDR= GR_Fh, 3, GR_LOG_TBL // address of 2^{f_high}
313}
314{.mlx
315 ldf8 FR_T_low= [ GR_Flow_ADDR ] // load T_low= 2^{f_low}
316 movl GR_EMIN= 0xc2fc0000 // EMIN= -126
317}
318;;
319
320{.mfi
321 ldf8 FR_T_high= [ GR_Fh_ADDR ] // load T_high= 2^{f_high}
322 (p7) fcmp.lt.s1 p12, p7= f8, FR_UF_LIMIT // x<underflow threshold ?
323 nop.i 0
324}
325;;
326
327{.mfb
328 setf.s FR_EXPMIN= GR_EMIN // FR_EXPMIN= EMIN
329 fma.s1 FR_P12= FR_COEFF2, FR_R, FR_COEFF1 // P12= C_1+C_2*r
330 (p12) br.cond.spnt OUT_RANGE_exp2
331}
332;;
333
334{.mfi
335 nop.m 0
336 fma.s1 FR_T_low_K= FR_T_low, FR_2_TO_K, f0 // T= 2^{K-126}*T_low
337 nop.i 0
338}
339;;
340
341{.mfi
342 nop.m 0
343 fma.s1 FR_P= FR_R, FR_P12, f0 // P= P12+r
344 nop.i 0
345}
346;;
347
348{.mfi
349 nop.m 0
350 fma.s1 FR_T= FR_T_low_K, FR_T_high, f0 // T= T*T_high
351 nop.i 0
352}
353;;
354
355{.mfi
356 nop.m 0
357 fcmp.lt.s0 p6, p8= f8, FR_EXPMIN // underflow (x<EMIN) ?
358 nop.i 0
359}
360;;
361
362{.mfb
363 nop.m 0
364 fma.s.s0 f8= FR_P, FR_T, FR_T // result= T+T*P
365 (p8) br.ret.sptk b0 // return
366}
367;;
368
369{.mfb
370 (p6) mov GR_Parameter_TAG= 164
371 nop.f 0
372 (p6) br.cond.sptk __libm_error_region
373}
374;;
375
376
377SPECIAL_exp2:
378{.mfi
379 nop.m 0
380 fclass.m p6, p0= f8, 0x22 // x= -Infinity ?
381 nop.i 0
382}
383;;
384
385{.mfi
386 nop.m 0
387 fclass.m p7, p0= f8, 0x21 // x= +Infinity ?
388 nop.i 0
389}
390;;
391
392{.mfi
393 nop.m 0
394 fclass.m p8, p0= f8, 0x7 // x= +/-Zero ?
395 nop.i 0
396}
397{.mfb
398 nop.m 0
399 (p6) mov f8= f0 // exp2(-Infinity)= 0
400 (p6) br.ret.spnt b0
401}
402;;
403
404{.mfb
405 nop.m 0
406 nop.f 0
407 (p7) br.ret.spnt b0 // exp2(+Infinity)= +Infinity
408}
409;;
410
411{.mfb
412 nop.m 0
413 (p8) mov f8= f1 // exp2(+/-0)= 1
414 (p8) br.ret.spnt b0
415}
416;;
417
418{.mfb
419 nop.m 0
420 fma.s.s0 f8= f8, f1, f0 // Remaining cases: NaNs
421 br.ret.sptk b0
422}
423;;
424
425
426OUT_RANGE_exp2:
427
428// overflow: p8= 1
429
430{.mii
431 (p8) mov GR_EXPMAX= 0x1fffe
432 nop.i 0
433 nop.i 0
434}
435;;
436
437{.mmb
438 (p8) mov GR_Parameter_TAG= 163
439 (p8) setf.exp FR_R= GR_EXPMAX
440 nop.b 999
441}
442;;
443
444{.mfi
445 nop.m 999
446 (p8) fma.s.s0 f8= FR_R, FR_R, f0 // Create overflow
447 nop.i 999
448}
449// underflow: p6= 1
450{.mii
451 (p6) mov GR_Parameter_TAG= 164
452 (p6) mov GR_EXPMAX= 1
453 nop.i 0
454}
455;;
456
457{.mmb
458 nop.m 0
459 (p6) setf.exp FR_R= GR_EXPMAX
460 nop.b 999
461}
462;;
463
464{.mfb
465 nop.m 999
466 (p6) fma.s.s0 f8= FR_R, FR_R, f0 // Create underflow
467 nop.b 0
468}
469;;
470
471GLOBAL_LIBM_END(exp2f)
472
ee618985 473
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474LOCAL_LIBM_ENTRY(__libm_error_region)
475
476.prologue
477{.mfi
478 add GR_Parameter_Y= -32, sp // Parameter 2 value
479 nop.f 0
480.save ar.pfs, GR_SAVE_PFS
481 mov GR_SAVE_PFS= ar.pfs // Save ar.pfs
482}
483
484{.mfi
485.fframe 64
486 add sp= -64, sp // Create new stack
487 nop.f 0
488 mov GR_SAVE_GP= gp // Save gp
489}
490;;
491
492{.mmi
493 stfs [ GR_Parameter_Y ]= FR_Y, 16 // STORE Parameter 2 on stack
494 add GR_Parameter_X= 16, sp // Parameter 1 address
495.save b0, GR_SAVE_B0
496 mov GR_SAVE_B0= b0 // Save b0
497}
498;;
499
500.body
501{.mib
502 stfs [ GR_Parameter_X ]= FR_X // STORE Parameter 1 on stack
503 add GR_Parameter_RESULT= 0, GR_Parameter_Y // Parameter 3 address
504 nop.b 0
505}
506{.mib
507 stfs [ GR_Parameter_Y ]= FR_RESULT // STORE Parameter 3 on stack
508 add GR_Parameter_Y= -16, GR_Parameter_Y
509 br.call.sptk b0= __libm_error_support# // Call error handling function
510}
511;;
512
513{.mmi
514 add GR_Parameter_RESULT= 48, sp
515 nop.m 0
516 nop.i 0
517}
518;;
519
520{.mmi
521 ldfs f8= [ GR_Parameter_RESULT ] // Get return result off stack
522.restore sp
523 add sp= 64, sp // Restore stack pointer
524 mov b0= GR_SAVE_B0 // Restore return address
525}
526;;
527
528{.mib
529 mov gp= GR_SAVE_GP // Restore gp
530 mov ar.pfs= GR_SAVE_PFS // Restore ar.pfs
531 br.ret.sptk b0 // Return
532}
533;;
534
535
536LOCAL_LIBM_END(__libm_error_region)
537
538.type __libm_error_support#, @function
539.global __libm_error_support#