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We stopped adding "Contributed by" or similar lines in sources in 2012 in favour of git logs and keeping the Contributors section of the glibc manual up to date. Removing these lines makes the license header a bit more consistent across files and also removes the possibility of error in attribution when license blocks or files are copied across since the contributed-by lines don't actually reflect reality in those cases. Move all "Contributed by" and similar lines (Written by, Test by, etc.) into a new file CONTRIBUTED-BY to retain record of these contributions. These contributors are also mentioned in manual/contrib.texi, so we just maintain this additional record as a courtesy to the earlier developers. The following scripts were used to filter a list of files to edit in place and to clean up the CONTRIBUTED-BY file respectively. These were not added to the glibc sources because they're not expected to be of any use in future given that this is a one time task: https://gist.github.com/siddhesh/b5ecac94eabfd72ed2916d6d8157e7dc https://gist.github.com/siddhesh/15ea1f5e435ace9774f485030695ee02 Reviewed-by: Carlos O'Donell <carlos@redhat.com>
723 lines
20 KiB
ArmAsm
723 lines
20 KiB
ArmAsm
.file "expf.s"
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// Copyright (c) 2000 - 2005, Intel Corporation
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// All rights reserved.
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//
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//
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// Redistribution and use in source and binary forms, with or without
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// modification, are permitted provided that the following conditions are
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// met:
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//
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// * Redistributions of source code must retain the above copyright
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// notice, this list of conditions and the following disclaimer.
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//
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// * Redistributions in binary form must reproduce the above copyright
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// notice, this list of conditions and the following disclaimer in the
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// documentation and/or other materials provided with the distribution.
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//
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// * The name of Intel Corporation may not be used to endorse or promote
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// products derived from this software without specific prior written
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// permission.
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// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL INTEL OR ITS
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// CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
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// EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
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// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
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// PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
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// OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY OR TORT (INCLUDING
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// NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
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// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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//
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// Intel Corporation is the author of this code, and requests that all
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// problem reports or change requests be submitted to it directly at
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// http://www.intel.com/software/products/opensource/libraries/num.htm.
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// History
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//*********************************************************************
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// 02/02/00 Original version
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// 04/04/00 Unwind support added
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// 08/15/00 Bundle added after call to __libm_error_support to properly
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// set [the previously overwritten] GR_Parameter_RESULT.
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// 08/21/00 Improvements to save 2 cycles on main path, and shorten x=0 case
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// 12/07/00 Widen main path, shorten x=inf, nan paths
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// 03/15/01 Fix monotonicity problem around x=0 for round to +inf
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// 02/05/02 Corrected uninitialize predicate in POSSIBLE_UNDERFLOW path
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// 05/20/02 Cleaned up namespace and sf0 syntax
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// 07/26/02 Algorithm changed, accuracy improved
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// 09/26/02 support of higher precision inputs added, underflow threshold
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// corrected
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// 11/15/02 Improved performance on Itanium 2, added possible over/under paths
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// 05/30/03 Set inexact flag on unmasked overflow/underflow
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// 03/31/05 Reformatted delimiters between data tables
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//
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//
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// API
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//*********************************************************************
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// float expf(float)
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//
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// Overview of operation
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//*********************************************************************
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// Take the input x. w is "how many log2/128 in x?"
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// w = x * 64/log2
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// NJ = int(w)
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// x = NJ*log2/64 + R
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// NJ = 64*n + j
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// x = n*log2 + (log2/64)*j + R
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//
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// So, exp(x) = 2^n * 2^(j/64)* exp(R)
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//
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// T = 2^n * 2^(j/64)
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// Construct 2^n
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// Get 2^(j/64) table
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// actually all the entries of 2^(j/64) table are stored in DP and
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// with exponent bits set to 0 -> multiplication on 2^n can be
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// performed by doing logical "or" operation with bits presenting 2^n
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// exp(R) = 1 + (exp(R) - 1)
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// P = exp(R) - 1 approximated by Taylor series of 3rd degree
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// P = A3*R^3 + A2*R^2 + R, A3 = 1/6, A2 = 1/2
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//
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// The final result is reconstructed as follows
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// exp(x) = T + T*P
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// Special values
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//*********************************************************************
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// expf(+0) = 1.0
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// expf(-0) = 1.0
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// expf(+qnan) = +qnan
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// expf(-qnan) = -qnan
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// expf(+snan) = +qnan
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// expf(-snan) = -qnan
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// expf(-inf) = +0
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// expf(+inf) = +inf
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// Overflow and Underflow
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//*********************************************************************
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// expf(x) = largest single normal when
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// x = 88.72283 = 0x42b17217
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// expf(x) = smallest single normal when
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// x = -87.33654 = 0xc2aeac4f
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// expf(x) = largest round-to-nearest single zero when
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// x = -103.97208 = 0xc2cff1b5
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// Registers used
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//*********************************************************************
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// Floating Point registers used:
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// f8, input
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// f6,f7, f9 -> f15, f32 -> f40
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// General registers used:
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// r3, r23 -> r38
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// Predicate registers used:
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// p10 -> p15
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// Assembly macros
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//*********************************************************************
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// integer registers used
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// scratch
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rNJ = r3
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rTmp = r23
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rJ = r23
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rN = r24
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rTblAddr = r25
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rA3 = r26
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rExpHalf = r27
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rLn2Div64 = r28
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r17ones_m1 = r29
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rGt_ln = r29
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rRightShifter = r30
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r64DivLn2 = r31
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// stacked
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GR_SAVE_PFS = r32
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GR_SAVE_B0 = r33
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GR_SAVE_GP = r34
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GR_Parameter_X = r35
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GR_Parameter_Y = r36
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GR_Parameter_RESULT = r37
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GR_Parameter_TAG = r38
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// floating point registers used
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FR_X = f10
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FR_Y = f1
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FR_RESULT = f8
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// scratch
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fRightShifter = f6
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f64DivLn2 = f7
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fNormX = f9
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fNint = f10
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fN = f11
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fR = f12
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fLn2Div64 = f13
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fA2 = f14
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fA3 = f15
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// stacked
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fP = f32
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fT = f33
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fMIN_SGL_OFLOW_ARG = f34
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fMAX_SGL_ZERO_ARG = f35
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fMAX_SGL_NORM_ARG = f36
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fMIN_SGL_NORM_ARG = f37
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fRSqr = f38
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fTmp = f39
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fGt_pln = f39
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fWre_urm_f8 = f40
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fFtz_urm_f8 = f40
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RODATA
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.align 16
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LOCAL_OBJECT_START(_expf_table)
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data4 0x42b17218 // Smallest sgl arg to overflow sgl result, +88.7228
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data4 0xc2cff1b5 // Largest sgl for rnd-to-nearest 0 result, -103.9720
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data4 0x42b17217 // Largest sgl arg to give normal sgl result, +88.7228
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data4 0xc2aeac4f // Smallest sgl arg to give normal sgl result, -87.3365
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//
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// 2^(j/64) table, j goes from 0 to 63
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data8 0x0000000000000000 // 2^(0/64)
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data8 0x00002C9A3E778061 // 2^(1/64)
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data8 0x000059B0D3158574 // 2^(2/64)
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data8 0x0000874518759BC8 // 2^(3/64)
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data8 0x0000B5586CF9890F // 2^(4/64)
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data8 0x0000E3EC32D3D1A2 // 2^(5/64)
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data8 0x00011301D0125B51 // 2^(6/64)
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data8 0x0001429AAEA92DE0 // 2^(7/64)
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data8 0x000172B83C7D517B // 2^(8/64)
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data8 0x0001A35BEB6FCB75 // 2^(9/64)
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data8 0x0001D4873168B9AA // 2^(10/64)
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data8 0x0002063B88628CD6 // 2^(11/64)
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data8 0x0002387A6E756238 // 2^(12/64)
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data8 0x00026B4565E27CDD // 2^(13/64)
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data8 0x00029E9DF51FDEE1 // 2^(14/64)
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data8 0x0002D285A6E4030B // 2^(15/64)
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data8 0x000306FE0A31B715 // 2^(16/64)
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data8 0x00033C08B26416FF // 2^(17/64)
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data8 0x000371A7373AA9CB // 2^(18/64)
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data8 0x0003A7DB34E59FF7 // 2^(19/64)
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data8 0x0003DEA64C123422 // 2^(20/64)
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data8 0x0004160A21F72E2A // 2^(21/64)
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data8 0x00044E086061892D // 2^(22/64)
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data8 0x000486A2B5C13CD0 // 2^(23/64)
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data8 0x0004BFDAD5362A27 // 2^(24/64)
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data8 0x0004F9B2769D2CA7 // 2^(25/64)
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data8 0x0005342B569D4F82 // 2^(26/64)
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data8 0x00056F4736B527DA // 2^(27/64)
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data8 0x0005AB07DD485429 // 2^(28/64)
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data8 0x0005E76F15AD2148 // 2^(29/64)
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data8 0x0006247EB03A5585 // 2^(30/64)
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data8 0x0006623882552225 // 2^(31/64)
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data8 0x0006A09E667F3BCD // 2^(32/64)
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data8 0x0006DFB23C651A2F // 2^(33/64)
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data8 0x00071F75E8EC5F74 // 2^(34/64)
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data8 0x00075FEB564267C9 // 2^(35/64)
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data8 0x0007A11473EB0187 // 2^(36/64)
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data8 0x0007E2F336CF4E62 // 2^(37/64)
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data8 0x00082589994CCE13 // 2^(38/64)
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data8 0x000868D99B4492ED // 2^(39/64)
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data8 0x0008ACE5422AA0DB // 2^(40/64)
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data8 0x0008F1AE99157736 // 2^(41/64)
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data8 0x00093737B0CDC5E5 // 2^(42/64)
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data8 0x00097D829FDE4E50 // 2^(43/64)
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data8 0x0009C49182A3F090 // 2^(44/64)
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data8 0x000A0C667B5DE565 // 2^(45/64)
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data8 0x000A5503B23E255D // 2^(46/64)
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data8 0x000A9E6B5579FDBF // 2^(47/64)
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data8 0x000AE89F995AD3AD // 2^(48/64)
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data8 0x000B33A2B84F15FB // 2^(49/64)
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data8 0x000B7F76F2FB5E47 // 2^(50/64)
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data8 0x000BCC1E904BC1D2 // 2^(51/64)
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data8 0x000C199BDD85529C // 2^(52/64)
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data8 0x000C67F12E57D14B // 2^(53/64)
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data8 0x000CB720DCEF9069 // 2^(54/64)
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data8 0x000D072D4A07897C // 2^(55/64)
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data8 0x000D5818DCFBA487 // 2^(56/64)
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data8 0x000DA9E603DB3285 // 2^(57/64)
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data8 0x000DFC97337B9B5F // 2^(58/64)
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data8 0x000E502EE78B3FF6 // 2^(59/64)
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data8 0x000EA4AFA2A490DA // 2^(60/64)
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data8 0x000EFA1BEE615A27 // 2^(61/64)
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data8 0x000F50765B6E4540 // 2^(62/64)
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data8 0x000FA7C1819E90D8 // 2^(63/64)
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LOCAL_OBJECT_END(_expf_table)
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.section .text
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GLOBAL_IEEE754_ENTRY(expf)
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{ .mlx
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addl rTblAddr = @ltoff(_expf_table),gp
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movl r64DivLn2 = 0x40571547652B82FE // 64/ln(2)
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}
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{ .mlx
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addl rA3 = 0x3E2AA, r0 // high bits of 1.0/6.0 rounded to SP
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movl rRightShifter = 0x43E8000000000000 // DP Right Shifter
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}
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;;
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{ .mfi
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// point to the beginning of the table
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ld8 rTblAddr = [rTblAddr]
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fclass.m p14, p0 = f8, 0x22 // test for -INF
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shl rA3 = rA3, 12 // 0x3E2AA000, approx to 1.0/6.0 in SP
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}
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{ .mfi
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nop.m 0
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fnorm.s1 fNormX = f8 // normalized x
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addl rExpHalf = 0xFFFE, r0 // exponent of 1/2
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}
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;;
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{ .mfi
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setf.d f64DivLn2 = r64DivLn2 // load 64/ln(2) to FP reg
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fclass.m p15, p0 = f8, 0x1e1 // test for NaT,NaN,+Inf
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nop.i 0
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}
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{ .mlx
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// load Right Shifter to FP reg
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setf.d fRightShifter = rRightShifter
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movl rLn2Div64 = 0x3F862E42FEFA39EF // DP ln(2)/64 in GR
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}
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;;
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{ .mfi
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nop.m 0
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fcmp.eq.s1 p13, p0 = f0, f8 // test for x = 0.0
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nop.i 0
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}
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{ .mfb
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setf.s fA3 = rA3 // load A3 to FP reg
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(p14) fma.s.s0 f8 = f0, f1, f0 // result if x = -inf
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(p14) br.ret.spnt b0 // exit here if x = -inf
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}
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;;
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{ .mfi
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setf.exp fA2 = rExpHalf // load A2 to FP reg
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fcmp.eq.s0 p6, p0 = f8, f0 // Dummy to flag denorm
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nop.i 0
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}
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{ .mfb
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setf.d fLn2Div64 = rLn2Div64 // load ln(2)/64 to FP reg
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(p15) fma.s.s0 f8 = f8, f1, f0 // result if x = NaT,NaN,+Inf
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(p15) br.ret.spnt b0 // exit here if x = NaT,NaN,+Inf
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}
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;;
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{ .mfb
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// overflow and underflow_zero threshold
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ldfps fMIN_SGL_OFLOW_ARG, fMAX_SGL_ZERO_ARG = [rTblAddr], 8
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(p13) fma.s.s0 f8 = f1, f1, f0 // result if x = 0.0
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(p13) br.ret.spnt b0 // exit here if x =0.0
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}
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;;
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// max normal and underflow_denorm threshold
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{ .mfi
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ldfps fMAX_SGL_NORM_ARG, fMIN_SGL_NORM_ARG = [rTblAddr], 8
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nop.f 0
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nop.i 0
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}
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;;
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{ .mfi
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nop.m 0
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// x*(64/ln(2)) + Right Shifter
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fma.s1 fNint = fNormX, f64DivLn2, fRightShifter
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nop.i 0
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}
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;;
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// Divide arguments into the following categories:
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// Certain Underflow p11 - -inf < x <= MAX_SGL_ZERO_ARG
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// Possible Underflow p13 - MAX_SGL_ZERO_ARG < x < MIN_SGL_NORM_ARG
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// Certain Safe - MIN_SGL_NORM_ARG <= x <= MAX_SGL_NORM_ARG
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// Possible Overflow p14 - MAX_SGL_NORM_ARG < x < MIN_SGL_OFLOW_ARG
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// Certain Overflow p15 - MIN_SGL_OFLOW_ARG <= x < +inf
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//
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// If the input is really a single arg, then there will never be
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// "Possible Overflow" arguments.
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//
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{ .mfi
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nop.m 0
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// check for overflow
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fcmp.ge.s1 p15, p0 = fNormX, fMIN_SGL_OFLOW_ARG
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nop.i 0
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}
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;;
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{ .mfi
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nop.m 0
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// check for underflow and tiny (+0) result
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fcmp.le.s1 p11, p0 = fNormX, fMAX_SGL_ZERO_ARG
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nop.i 0
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}
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{ .mfb
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nop.m 0
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fms.s1 fN = fNint, f1, fRightShifter // n in FP register
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// branch out if overflow
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(p15) br.cond.spnt EXP_CERTAIN_OVERFLOW
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}
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;;
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{ .mfb
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getf.sig rNJ = fNint // bits of n, j
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// check for underflow and deno result
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fcmp.lt.s1 p13, p0 = fNormX, fMIN_SGL_NORM_ARG
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// branch out if underflow and tiny (+0) result
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(p11) br.cond.spnt EXP_CERTAIN_UNDERFLOW
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}
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;;
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{ .mfi
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nop.m 0
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// check for possible overflow
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fcmp.gt.s1 p14, p0 = fNormX, fMAX_SGL_NORM_ARG
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extr.u rJ = rNJ, 0, 6 // bits of j
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}
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{ .mfi
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addl rN = 0xFFFF - 63, rNJ // biased and shifted n
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fnma.s1 fR = fLn2Div64, fN, fNormX // R = x - N*ln(2)/64
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nop.i 0
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}
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;;
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{ .mfi
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shladd rJ = rJ, 3, rTblAddr // address in the 2^(j/64) table
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nop.f 0
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shr rN = rN, 6 // biased n
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}
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;;
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{ .mfi
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ld8 rJ = [rJ]
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nop.f 0
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shl rN = rN, 52 // 2^n bits in DP format
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}
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;;
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{ .mfi
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or rN = rN, rJ // bits of 2^n * 2^(j/64) in DP format
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nop.f 0
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nop.i 0
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}
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;;
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{ .mfi
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setf.d fT = rN // 2^n * 2^(j/64)
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fma.s1 fP = fA3, fR, fA2 // A3*R + A2
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nop.i 0
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}
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{ .mfi
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nop.m 0
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fma.s1 fRSqr = fR, fR, f0 // R^2
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nop.i 0
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}
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;;
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{ .mfi
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nop.m 0
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fma.s1 fP = fP, fRSqr, fR // P = (A3*R + A2)*R^2 + R
|
|
nop.i 0
|
|
}
|
|
;;
|
|
|
|
{ .mbb
|
|
nop.m 0
|
|
// branch out if possible underflow
|
|
(p13) br.cond.spnt EXP_POSSIBLE_UNDERFLOW
|
|
// branch out if possible overflow result
|
|
(p14) br.cond.spnt EXP_POSSIBLE_OVERFLOW
|
|
}
|
|
;;
|
|
|
|
{ .mfb
|
|
nop.m 0
|
|
// final result in the absence of over- and underflow
|
|
fma.s.s0 f8 = fP, fT, fT
|
|
// exit here in the absence of over- and underflow
|
|
br.ret.sptk b0
|
|
}
|
|
;;
|
|
|
|
EXP_POSSIBLE_OVERFLOW:
|
|
|
|
// Here if fMAX_SGL_NORM_ARG < x < fMIN_SGL_OFLOW_ARG
|
|
// This cannot happen if input is a single, only if input higher precision.
|
|
// Overflow is a possibility, not a certainty.
|
|
|
|
// Recompute result using status field 2 with user's rounding mode,
|
|
// and wre set. If result is larger than largest single, then we have
|
|
// overflow
|
|
|
|
{ .mfi
|
|
mov rGt_ln = 0x1007f // Exponent for largest single + 1 ulp
|
|
fsetc.s2 0x7F,0x42 // Get user's round mode, set wre
|
|
nop.i 0
|
|
}
|
|
;;
|
|
|
|
{ .mfi
|
|
setf.exp fGt_pln = rGt_ln // Create largest single + 1 ulp
|
|
fma.s.s2 fWre_urm_f8 = fP, fT, fT // Result with wre set
|
|
nop.i 0
|
|
}
|
|
;;
|
|
|
|
{ .mfi
|
|
nop.m 0
|
|
fsetc.s2 0x7F,0x40 // Turn off wre in sf2
|
|
nop.i 0
|
|
}
|
|
;;
|
|
|
|
{ .mfi
|
|
nop.m 0
|
|
fcmp.ge.s1 p6, p0 = fWre_urm_f8, fGt_pln // Test for overflow
|
|
nop.i 0
|
|
}
|
|
;;
|
|
|
|
{ .mfb
|
|
nop.m 0
|
|
nop.f 0
|
|
(p6) br.cond.spnt EXP_CERTAIN_OVERFLOW // Branch if overflow
|
|
}
|
|
;;
|
|
|
|
{ .mfb
|
|
nop.m 0
|
|
fma.s.s0 f8 = fP, fT, fT
|
|
br.ret.sptk b0 // Exit if really no overflow
|
|
}
|
|
;;
|
|
|
|
// here if overflow
|
|
EXP_CERTAIN_OVERFLOW:
|
|
{ .mmi
|
|
addl r17ones_m1 = 0x1FFFE, r0
|
|
;;
|
|
setf.exp fTmp = r17ones_m1
|
|
nop.i 0
|
|
}
|
|
;;
|
|
|
|
{ .mfi
|
|
alloc r32=ar.pfs,0,3,4,0
|
|
fmerge.s FR_X = f8,f8
|
|
nop.i 0
|
|
}
|
|
{ .mfb
|
|
mov GR_Parameter_TAG = 16
|
|
fma.s.s0 FR_RESULT = fTmp, fTmp, fTmp // Set I,O and +INF result
|
|
br.cond.sptk __libm_error_region
|
|
}
|
|
;;
|
|
|
|
EXP_POSSIBLE_UNDERFLOW:
|
|
|
|
// Here if fMAX_SGL_ZERO_ARG < x < fMIN_SGL_NORM_ARG
|
|
// Underflow is a possibility, not a certainty
|
|
|
|
// We define an underflow when the answer with
|
|
// ftz set
|
|
// is zero (tiny numbers become zero)
|
|
|
|
// Notice (from below) that if we have an unlimited exponent range,
|
|
// then there is an extra machine number E between the largest denormal and
|
|
// the smallest normal.
|
|
|
|
// So if with unbounded exponent we round to E or below, then we are
|
|
// tiny and underflow has occurred.
|
|
|
|
// But notice that you can be in a situation where we are tiny, namely
|
|
// rounded to E, but when the exponent is bounded we round to smallest
|
|
// normal. So the answer can be the smallest normal with underflow.
|
|
|
|
// E
|
|
// -----+--------------------+--------------------+-----
|
|
// | | |
|
|
// 1.1...10 2^-3fff 1.1...11 2^-3fff 1.0...00 2^-3ffe
|
|
// 0.1...11 2^-3ffe (biased, 1)
|
|
// largest dn smallest normal
|
|
|
|
{ .mfi
|
|
nop.m 0
|
|
fsetc.s2 0x7F,0x41 // Get user's round mode, set ftz
|
|
nop.i 0
|
|
}
|
|
;;
|
|
|
|
{ .mfi
|
|
nop.m 0
|
|
fma.s.s2 fFtz_urm_f8 = fP, fT, fT // Result with ftz set
|
|
nop.i 0
|
|
}
|
|
;;
|
|
|
|
{ .mfi
|
|
nop.m 0
|
|
fsetc.s2 0x7F,0x40 // Turn off ftz in sf2
|
|
nop.i 0
|
|
}
|
|
;;
|
|
|
|
{ .mfi
|
|
nop.m 0
|
|
fcmp.eq.s1 p6, p7 = fFtz_urm_f8, f0 // Test for underflow
|
|
nop.i 0
|
|
}
|
|
{ .mfi
|
|
nop.m 0
|
|
fma.s.s0 f8 = fP, fT, fT // Compute result, set I, maybe U
|
|
nop.i 0
|
|
}
|
|
;;
|
|
|
|
{ .mbb
|
|
nop.m 0
|
|
(p6) br.cond.spnt EXP_UNDERFLOW_COMMON // Branch if really underflow
|
|
(p7) br.ret.sptk b0 // Exit if really no underflow
|
|
}
|
|
;;
|
|
|
|
EXP_CERTAIN_UNDERFLOW:
|
|
// Here if x < fMAX_SGL_ZERO_ARG
|
|
// Result will be zero (or smallest denorm if round to +inf) with I, U set
|
|
{ .mmi
|
|
mov rTmp = 1
|
|
;;
|
|
setf.exp fTmp = rTmp // Form small normal
|
|
nop.i 0
|
|
}
|
|
;;
|
|
|
|
{ .mfi
|
|
nop.m 0
|
|
fmerge.se fTmp = fTmp, f64DivLn2 // Small with non-trial signif
|
|
nop.i 0
|
|
}
|
|
;;
|
|
|
|
{ .mfb
|
|
nop.m 0
|
|
fma.s.s0 f8 = fTmp, fTmp, f0 // Set I,U, tiny (+0.0) result
|
|
br.cond.sptk EXP_UNDERFLOW_COMMON
|
|
}
|
|
;;
|
|
|
|
EXP_UNDERFLOW_COMMON:
|
|
// Determine if underflow result is zero or nonzero
|
|
{ .mfi
|
|
alloc r32=ar.pfs,0,3,4,0
|
|
fcmp.eq.s1 p6, p0 = f8, f0
|
|
nop.i 0
|
|
}
|
|
;;
|
|
|
|
{ .mfb
|
|
nop.m 0
|
|
fmerge.s FR_X = fNormX,fNormX
|
|
(p6) br.cond.spnt EXP_UNDERFLOW_ZERO
|
|
}
|
|
;;
|
|
|
|
EXP_UNDERFLOW_NONZERO:
|
|
// Here if x < fMIN_SGL_NORM_ARG and result nonzero;
|
|
// I, U are set
|
|
{ .mfb
|
|
mov GR_Parameter_TAG = 17
|
|
nop.f 0 // FR_RESULT already set
|
|
br.cond.sptk __libm_error_region
|
|
}
|
|
;;
|
|
|
|
EXP_UNDERFLOW_ZERO:
|
|
// Here if x < fMIN_SGL_NORM_ARG and result zero;
|
|
// I, U are set
|
|
{ .mfb
|
|
mov GR_Parameter_TAG = 17
|
|
nop.f 0 // FR_RESULT already set
|
|
br.cond.sptk __libm_error_region
|
|
}
|
|
;;
|
|
|
|
GLOBAL_IEEE754_END(expf)
|
|
libm_alias_float_other (__exp, exp)
|
|
#ifdef SHARED
|
|
.symver expf,expf@@GLIBC_2.27
|
|
.weak __expf_compat
|
|
.set __expf_compat,__expf
|
|
.symver __expf_compat,expf@GLIBC_2.2
|
|
#endif
|
|
|
|
|
|
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
|
|
{ .mfi
|
|
stfs [GR_Parameter_X] = FR_X // Store Parameter 1 on stack
|
|
nop.f 0
|
|
add GR_Parameter_RESULT = 0,GR_Parameter_Y // Parameter 3 address
|
|
}
|
|
{ .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
|
|
add GR_Parameter_RESULT = 48,sp
|
|
nop.m 0
|
|
nop.i 0
|
|
};;
|
|
|
|
{ .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#
|