Back to home page

LXR

 
 

    


File indexing completed on 2025-05-11 08:23:49

0001 #include "fpsp-namespace.h"
0002 //
0003 //
0004 //  ssinh.sa 3.1 12/10/90
0005 //
0006 //       The entry point sSinh computes the hyperbolic sine of
0007 //       an input argument; sSinhd does the same except for denormalized
0008 //       input.
0009 //
0010 //       Input: Double-extended number X in location pointed to
0011 //      by address register a0.
0012 //
0013 //       Output: The value sinh(X) returned in floating-point register Fp0.
0014 //
0015 //       Accuracy and Monotonicity: The returned result is within 3 ulps in
0016 //               64 significant bit, i.e. within 0.5001 ulp to 53 bits if the
0017 //               result is subsequently rounded to double precision. The
0018 //               result is provably monotonic in double precision.
0019 //
0020 //       Speed: The program sSINH takes approximately 280 cycles.
0021 //
0022 //       Algorithm:
0023 //
0024 //       SINH
0025 //       1. If |X| > 16380 log2, go to 3.
0026 //
0027 //       2. (|X| <= 16380 log2) Sinh(X) is obtained by the formulae
0028 //               y = |X|, sgn = sign(X), and z = expm1(Y),
0029 //               sinh(X) = sgn*(1/2)*( z + z/(1+z) ).
0030 //          Exit.
0031 //
0032 //       3. If |X| > 16480 log2, go to 5.
0033 //
0034 //       4. (16380 log2 < |X| <= 16480 log2)
0035 //               sinh(X) = sign(X) * exp(|X|)/2.
0036 //          However, invoking exp(|X|) may cause premature overflow.
0037 //          Thus, we calculate sinh(X) as follows:
0038 //             Y       := |X|
0039 //             sgn     := sign(X)
0040 //             sgnFact := sgn * 2**(16380)
0041 //             Y'      := Y - 16381 log2
0042 //             sinh(X) := sgnFact * exp(Y').
0043 //          Exit.
0044 //
0045 //       5. (|X| > 16480 log2) sinh(X) must overflow. Return
0046 //          sign(X)*Huge*Huge to generate overflow and an infinity with
0047 //          the appropriate sign. Huge is the largest finite number in
0048 //          extended format. Exit.
0049 //
0050 
0051 //      Copyright (C) Motorola, Inc. 1990
0052 //          All Rights Reserved
0053 //
0054 //  THIS IS UNPUBLISHED PROPRIETARY SOURCE CODE OF MOTOROLA
0055 //  The copyright notice above does not evidence any
0056 //  actual or intended publication of such source code.
0057 
0058 //SSINH idnt    2,1 | Motorola 040 Floating Point Software Package
0059 
0060     |section    8
0061 
0062 T1: .long 0x40C62D38,0xD3D64634 // ... 16381 LOG2 LEAD
0063 T2: .long 0x3D6F90AE,0xB1E75CC7 // ... 16381 LOG2 TRAIL
0064 
0065     |xref   t_frcinx
0066     |xref   t_ovfl
0067     |xref   t_extdnrm
0068     |xref   setox
0069     |xref   setoxm1
0070 
0071     .global ssinhd
0072 ssinhd:
0073 //--SINH(X) = X FOR DENORMALIZED X
0074 
0075     bra t_extdnrm
0076 
0077     .global ssinh
0078 ssinh:
0079     fmovex  (%a0),%fp0  // ...LOAD INPUT
0080 
0081     movel   (%a0),%d0
0082     movew   4(%a0),%d0
0083     movel   %d0,%a1     // save a copy of original (compacted) operand
0084     andl    #0x7FFFFFFF,%d0
0085     cmpl    #0x400CB167,%d0
0086     bgts    SINHBIG
0087 
0088 //--THIS IS THE USUAL CASE, |X| < 16380 LOG2
0089 //--Y = |X|, Z = EXPM1(Y), SINH(X) = SIGN(X)*(1/2)*( Z + Z/(1+Z) )
0090 
0091     fabsx   %fp0        // ...Y = |X|
0092 
0093     moveml  %a1/%d1,-(%sp)
0094     fmovemx %fp0-%fp0,(%a0)
0095     clrl    %d1
0096     bsr setoxm1     // ...FP0 IS Z = EXPM1(Y)
0097     fmovel  #0,%fpcr
0098     moveml  (%sp)+,%a1/%d1
0099 
0100     fmovex  %fp0,%fp1
0101     fadds   #0x3F800000,%fp1    // ...1+Z
0102     fmovex  %fp0,-(%sp)
0103     fdivx   %fp1,%fp0       // ...Z/(1+Z)
0104     movel   %a1,%d0
0105     andl    #0x80000000,%d0
0106     orl #0x3F000000,%d0
0107     faddx   (%sp)+,%fp0
0108     movel   %d0,-(%sp)
0109 
0110     fmovel  %d1,%fpcr
0111     fmuls   (%sp)+,%fp0 //last fp inst - possible exceptions set
0112 
0113     bra t_frcinx
0114 
0115 SINHBIG:
0116     cmpl    #0x400CB2B3,%d0
0117     bgt t_ovfl
0118     fabsx   %fp0
0119     fsubd   T1(%pc),%fp0    // ...(|X|-16381LOG2_LEAD)
0120     movel   #0,-(%sp)
0121     movel   #0x80000000,-(%sp)
0122     movel   %a1,%d0
0123     andl    #0x80000000,%d0
0124     orl #0x7FFB0000,%d0
0125     movel   %d0,-(%sp)  // ...EXTENDED FMT
0126     fsubd   T2(%pc),%fp0    // ...|X| - 16381 LOG2, ACCURATE
0127 
0128     movel   %d1,-(%sp)
0129     clrl    %d1
0130     fmovemx %fp0-%fp0,(%a0)
0131     bsr setox
0132     fmovel  (%sp)+,%fpcr
0133 
0134     fmulx   (%sp)+,%fp0 //possible exception
0135     bra t_frcinx
0136 
0137     |end