linux/arch/m68k/fpsp040/ssin.S
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   1|
   2|       ssin.sa 3.3 7/29/91
   3|
   4|       The entry point sSIN computes the sine of an input argument
   5|       sCOS computes the cosine, and sSINCOS computes both. The
   6|       corresponding entry points with a "d" computes the same
   7|       corresponding function values for denormalized inputs.
   8|
   9|       Input: Double-extended number X in location pointed to
  10|               by address register a0.
  11|
  12|       Output: The function value sin(X) or cos(X) returned in Fp0 if SIN or
  13|               COS is requested. Otherwise, for SINCOS, sin(X) is returned
  14|               in Fp0, and cos(X) is returned in Fp1.
  15|
  16|       Modifies: Fp0 for SIN or COS; both Fp0 and Fp1 for SINCOS.
  17|
  18|       Accuracy and Monotonicity: The returned result is within 1 ulp in
  19|               64 significant bit, i.e. within 0.5001 ulp to 53 bits if the
  20|               result is subsequently rounded to double precision. The
  21|               result is provably monotonic in double precision.
  22|
  23|       Speed: The programs sSIN and sCOS take approximately 150 cycles for
  24|               input argument X such that |X| < 15Pi, which is the usual
  25|               situation. The speed for sSINCOS is approximately 190 cycles.
  26|
  27|       Algorithm:
  28|
  29|       SIN and COS:
  30|       1. If SIN is invoked, set AdjN := 0; otherwise, set AdjN := 1.
  31|
  32|       2. If |X| >= 15Pi or |X| < 2**(-40), go to 7.
  33|
  34|       3. Decompose X as X = N(Pi/2) + r where |r| <= Pi/4. Let
  35|               k = N mod 4, so in particular, k = 0,1,2,or 3. Overwrite
  36|               k by k := k + AdjN.
  37|
  38|       4. If k is even, go to 6.
  39|
  40|       5. (k is odd) Set j := (k-1)/2, sgn := (-1)**j. Return sgn*cos(r)
  41|               where cos(r) is approximated by an even polynomial in r,
  42|               1 + r*r*(B1+s*(B2+ ... + s*B8)),        s = r*r.
  43|               Exit.
  44|
  45|       6. (k is even) Set j := k/2, sgn := (-1)**j. Return sgn*sin(r)
  46|               where sin(r) is approximated by an odd polynomial in r
  47|               r + r*s*(A1+s*(A2+ ... + s*A7)),        s = r*r.
  48|               Exit.
  49|
  50|       7. If |X| > 1, go to 9.
  51|
  52|       8. (|X|<2**(-40)) If SIN is invoked, return X; otherwise return 1.
  53|
  54|       9. Overwrite X by X := X rem 2Pi. Now that |X| <= Pi, go back to 3.
  55|
  56|       SINCOS:
  57|       1. If |X| >= 15Pi or |X| < 2**(-40), go to 6.
  58|
  59|       2. Decompose X as X = N(Pi/2) + r where |r| <= Pi/4. Let
  60|               k = N mod 4, so in particular, k = 0,1,2,or 3.
  61|
  62|       3. If k is even, go to 5.
  63|
  64|       4. (k is odd) Set j1 := (k-1)/2, j2 := j1 (EOR) (k mod 2), i.e.
  65|               j1 exclusive or with the l.s.b. of k.
  66|               sgn1 := (-1)**j1, sgn2 := (-1)**j2.
  67|               SIN(X) = sgn1 * cos(r) and COS(X) = sgn2*sin(r) where
  68|               sin(r) and cos(r) are computed as odd and even polynomials
  69|               in r, respectively. Exit
  70|
  71|       5. (k is even) Set j1 := k/2, sgn1 := (-1)**j1.
  72|               SIN(X) = sgn1 * sin(r) and COS(X) = sgn1*cos(r) where
  73|               sin(r) and cos(r) are computed as odd and even polynomials
  74|               in r, respectively. Exit
  75|
  76|       6. If |X| > 1, go to 8.
  77|
  78|       7. (|X|<2**(-40)) SIN(X) = X and COS(X) = 1. Exit.
  79|
  80|       8. Overwrite X by X := X rem 2Pi. Now that |X| <= Pi, go back to 2.
  81|
  82
  83|               Copyright (C) Motorola, Inc. 1990
  84|                       All Rights Reserved
  85|
  86|       For details on the license for this file, please see the
  87|       file, README, in this same directory.
  88
  89|SSIN   idnt    2,1 | Motorola 040 Floating Point Software Package
  90
  91        |section        8
  92
  93#include "fpsp.h"
  94
  95BOUNDS1:        .long 0x3FD78000,0x4004BC7E
  96TWOBYPI:        .long 0x3FE45F30,0x6DC9C883
  97
  98SINA7:  .long 0xBD6AAA77,0xCCC994F5
  99SINA6:  .long 0x3DE61209,0x7AAE8DA1
 100
 101SINA5:  .long 0xBE5AE645,0x2A118AE4
 102SINA4:  .long 0x3EC71DE3,0xA5341531
 103
 104SINA3:  .long 0xBF2A01A0,0x1A018B59,0x00000000,0x00000000
 105
 106SINA2:  .long 0x3FF80000,0x88888888,0x888859AF,0x00000000
 107
 108SINA1:  .long 0xBFFC0000,0xAAAAAAAA,0xAAAAAA99,0x00000000
 109
 110COSB8:  .long 0x3D2AC4D0,0xD6011EE3
 111COSB7:  .long 0xBDA9396F,0x9F45AC19
 112
 113COSB6:  .long 0x3E21EED9,0x0612C972
 114COSB5:  .long 0xBE927E4F,0xB79D9FCF
 115
 116COSB4:  .long 0x3EFA01A0,0x1A01D423,0x00000000,0x00000000
 117
 118COSB3:  .long 0xBFF50000,0xB60B60B6,0x0B61D438,0x00000000
 119
 120COSB2:  .long 0x3FFA0000,0xAAAAAAAA,0xAAAAAB5E
 121COSB1:  .long 0xBF000000
 122
 123INVTWOPI: .long 0x3FFC0000,0xA2F9836E,0x4E44152A
 124
 125TWOPI1: .long 0x40010000,0xC90FDAA2,0x00000000,0x00000000
 126TWOPI2: .long 0x3FDF0000,0x85A308D4,0x00000000,0x00000000
 127
 128        |xref   PITBL
 129
 130        .set    INARG,FP_SCR4
 131
 132        .set    X,FP_SCR5
 133        .set    XDCARE,X+2
 134        .set    XFRAC,X+4
 135
 136        .set    RPRIME,FP_SCR1
 137        .set    SPRIME,FP_SCR2
 138
 139        .set    POSNEG1,L_SCR1
 140        .set    TWOTO63,L_SCR1
 141
 142        .set    ENDFLAG,L_SCR2
 143        .set    N,L_SCR2
 144
 145        .set    ADJN,L_SCR3
 146
 147        | xref  t_frcinx
 148        |xref   t_extdnrm
 149        |xref   sto_cos
 150
 151        .global ssind
 152ssind:
 153|--SIN(X) = X FOR DENORMALIZED X
 154        bra             t_extdnrm
 155
 156        .global scosd
 157scosd:
 158|--COS(X) = 1 FOR DENORMALIZED X
 159
 160        fmoves          #0x3F800000,%fp0
 161|
 162|       9D25B Fix: Sometimes the previous fmove.s sets fpsr bits
 163|
 164        fmovel          #0,%fpsr
 165|
 166        bra             t_frcinx
 167
 168        .global ssin
 169ssin:
 170|--SET ADJN TO 0
 171        movel           #0,ADJN(%a6)
 172        bras            SINBGN
 173
 174        .global scos
 175scos:
 176|--SET ADJN TO 1
 177        movel           #1,ADJN(%a6)
 178
 179SINBGN:
 180|--SAVE FPCR, FP1. CHECK IF |X| IS TOO SMALL OR LARGE
 181
 182        fmovex          (%a0),%fp0      | ...LOAD INPUT
 183
 184        movel           (%a0),%d0
 185        movew           4(%a0),%d0
 186        fmovex          %fp0,X(%a6)
 187        andil           #0x7FFFFFFF,%d0         | ...COMPACTIFY X
 188
 189        cmpil           #0x3FD78000,%d0         | ...|X| >= 2**(-40)?
 190        bges            SOK1
 191        bra             SINSM
 192
 193SOK1:
 194        cmpil           #0x4004BC7E,%d0         | ...|X| < 15 PI?
 195        blts            SINMAIN
 196        bra             REDUCEX
 197
 198SINMAIN:
 199|--THIS IS THE USUAL CASE, |X| <= 15 PI.
 200|--THE ARGUMENT REDUCTION IS DONE BY TABLE LOOK UP.
 201        fmovex          %fp0,%fp1
 202        fmuld           TWOBYPI,%fp1    | ...X*2/PI
 203
 204|--HIDE THE NEXT THREE INSTRUCTIONS
 205        lea             PITBL+0x200,%a1 | ...TABLE OF N*PI/2, N = -32,...,32
 206
 207
 208|--FP1 IS NOW READY
 209        fmovel          %fp1,N(%a6)             | ...CONVERT TO INTEGER
 210
 211        movel           N(%a6),%d0
 212        asll            #4,%d0
 213        addal           %d0,%a1 | ...A1 IS THE ADDRESS OF N*PIBY2
 214|                               ...WHICH IS IN TWO PIECES Y1 & Y2
 215
 216        fsubx           (%a1)+,%fp0     | ...X-Y1
 217|--HIDE THE NEXT ONE
 218        fsubs           (%a1),%fp0      | ...FP0 IS R = (X-Y1)-Y2
 219
 220SINCONT:
 221|--continuation from REDUCEX
 222
 223|--GET N+ADJN AND SEE IF SIN(R) OR COS(R) IS NEEDED
 224        movel           N(%a6),%d0
 225        addl            ADJN(%a6),%d0   | ...SEE IF D0 IS ODD OR EVEN
 226        rorl            #1,%d0  | ...D0 WAS ODD IFF D0 IS NEGATIVE
 227        cmpil           #0,%d0
 228        blt             COSPOLY
 229
 230SINPOLY:
 231|--LET J BE THE LEAST SIG. BIT OF D0, LET SGN := (-1)**J.
 232|--THEN WE RETURN       SGN*SIN(R). SGN*SIN(R) IS COMPUTED BY
 233|--R' + R'*S*(A1 + S(A2 + S(A3 + S(A4 + ... + SA7)))), WHERE
 234|--R' = SGN*R, S=R*R. THIS CAN BE REWRITTEN AS
 235|--R' + R'*S*( [A1+T(A3+T(A5+TA7))] + [S(A2+T(A4+TA6))])
 236|--WHERE T=S*S.
 237|--NOTE THAT A3 THROUGH A7 ARE STORED IN DOUBLE PRECISION
 238|--WHILE A1 AND A2 ARE IN DOUBLE-EXTENDED FORMAT.
 239        fmovex          %fp0,X(%a6)     | ...X IS R
 240        fmulx           %fp0,%fp0       | ...FP0 IS S
 241|---HIDE THE NEXT TWO WHILE WAITING FOR FP0
 242        fmoved          SINA7,%fp3
 243        fmoved          SINA6,%fp2
 244|--FP0 IS NOW READY
 245        fmovex          %fp0,%fp1
 246        fmulx           %fp1,%fp1       | ...FP1 IS T
 247|--HIDE THE NEXT TWO WHILE WAITING FOR FP1
 248
 249        rorl            #1,%d0
 250        andil           #0x80000000,%d0
 251|                               ...LEAST SIG. BIT OF D0 IN SIGN POSITION
 252        eorl            %d0,X(%a6)      | ...X IS NOW R'= SGN*R
 253
 254        fmulx           %fp1,%fp3       | ...TA7
 255        fmulx           %fp1,%fp2       | ...TA6
 256
 257        faddd           SINA5,%fp3 | ...A5+TA7
 258        faddd           SINA4,%fp2 | ...A4+TA6
 259
 260        fmulx           %fp1,%fp3       | ...T(A5+TA7)
 261        fmulx           %fp1,%fp2       | ...T(A4+TA6)
 262
 263        faddd           SINA3,%fp3 | ...A3+T(A5+TA7)
 264        faddx           SINA2,%fp2 | ...A2+T(A4+TA6)
 265
 266        fmulx           %fp3,%fp1       | ...T(A3+T(A5+TA7))
 267
 268        fmulx           %fp0,%fp2       | ...S(A2+T(A4+TA6))
 269        faddx           SINA1,%fp1 | ...A1+T(A3+T(A5+TA7))
 270        fmulx           X(%a6),%fp0     | ...R'*S
 271
 272        faddx           %fp2,%fp1       | ...[A1+T(A3+T(A5+TA7))]+[S(A2+T(A4+TA6))]
 273|--FP3 RELEASED, RESTORE NOW AND TAKE SOME ADVANTAGE OF HIDING
 274|--FP2 RELEASED, RESTORE NOW AND TAKE FULL ADVANTAGE OF HIDING
 275
 276
 277        fmulx           %fp1,%fp0               | ...SIN(R')-R'
 278|--FP1 RELEASED.
 279
 280        fmovel          %d1,%FPCR               |restore users exceptions
 281        faddx           X(%a6),%fp0             |last inst - possible exception set
 282        bra             t_frcinx
 283
 284
 285COSPOLY:
 286|--LET J BE THE LEAST SIG. BIT OF D0, LET SGN := (-1)**J.
 287|--THEN WE RETURN       SGN*COS(R). SGN*COS(R) IS COMPUTED BY
 288|--SGN + S'*(B1 + S(B2 + S(B3 + S(B4 + ... + SB8)))), WHERE
 289|--S=R*R AND S'=SGN*S. THIS CAN BE REWRITTEN AS
 290|--SGN + S'*([B1+T(B3+T(B5+TB7))] + [S(B2+T(B4+T(B6+TB8)))])
 291|--WHERE T=S*S.
 292|--NOTE THAT B4 THROUGH B8 ARE STORED IN DOUBLE PRECISION
 293|--WHILE B2 AND B3 ARE IN DOUBLE-EXTENDED FORMAT, B1 IS -1/2
 294|--AND IS THEREFORE STORED AS SINGLE PRECISION.
 295
 296        fmulx           %fp0,%fp0       | ...FP0 IS S
 297|---HIDE THE NEXT TWO WHILE WAITING FOR FP0
 298        fmoved          COSB8,%fp2
 299        fmoved          COSB7,%fp3
 300|--FP0 IS NOW READY
 301        fmovex          %fp0,%fp1
 302        fmulx           %fp1,%fp1       | ...FP1 IS T
 303|--HIDE THE NEXT TWO WHILE WAITING FOR FP1
 304        fmovex          %fp0,X(%a6)     | ...X IS S
 305        rorl            #1,%d0
 306        andil           #0x80000000,%d0
 307|                       ...LEAST SIG. BIT OF D0 IN SIGN POSITION
 308
 309        fmulx           %fp1,%fp2       | ...TB8
 310|--HIDE THE NEXT TWO WHILE WAITING FOR THE XU
 311        eorl            %d0,X(%a6)      | ...X IS NOW S'= SGN*S
 312        andil           #0x80000000,%d0
 313
 314        fmulx           %fp1,%fp3       | ...TB7
 315|--HIDE THE NEXT TWO WHILE WAITING FOR THE XU
 316        oril            #0x3F800000,%d0 | ...D0 IS SGN IN SINGLE
 317        movel           %d0,POSNEG1(%a6)
 318
 319        faddd           COSB6,%fp2 | ...B6+TB8
 320        faddd           COSB5,%fp3 | ...B5+TB7
 321
 322        fmulx           %fp1,%fp2       | ...T(B6+TB8)
 323        fmulx           %fp1,%fp3       | ...T(B5+TB7)
 324
 325        faddd           COSB4,%fp2 | ...B4+T(B6+TB8)
 326        faddx           COSB3,%fp3 | ...B3+T(B5+TB7)
 327
 328        fmulx           %fp1,%fp2       | ...T(B4+T(B6+TB8))
 329        fmulx           %fp3,%fp1       | ...T(B3+T(B5+TB7))
 330
 331        faddx           COSB2,%fp2 | ...B2+T(B4+T(B6+TB8))
 332        fadds           COSB1,%fp1 | ...B1+T(B3+T(B5+TB7))
 333
 334        fmulx           %fp2,%fp0       | ...S(B2+T(B4+T(B6+TB8)))
 335|--FP3 RELEASED, RESTORE NOW AND TAKE SOME ADVANTAGE OF HIDING
 336|--FP2 RELEASED.
 337
 338
 339        faddx           %fp1,%fp0
 340|--FP1 RELEASED
 341
 342        fmulx           X(%a6),%fp0
 343
 344        fmovel          %d1,%FPCR               |restore users exceptions
 345        fadds           POSNEG1(%a6),%fp0       |last inst - possible exception set
 346        bra             t_frcinx
 347
 348
 349SINBORS:
 350|--IF |X| > 15PI, WE USE THE GENERAL ARGUMENT REDUCTION.
 351|--IF |X| < 2**(-40), RETURN X OR 1.
 352        cmpil           #0x3FFF8000,%d0
 353        bgts            REDUCEX
 354
 355
 356SINSM:
 357        movel           ADJN(%a6),%d0
 358        cmpil           #0,%d0
 359        bgts            COSTINY
 360
 361SINTINY:
 362        movew           #0x0000,XDCARE(%a6)     | ...JUST IN CASE
 363        fmovel          %d1,%FPCR               |restore users exceptions
 364        fmovex          X(%a6),%fp0             |last inst - possible exception set
 365        bra             t_frcinx
 366
 367
 368COSTINY:
 369        fmoves          #0x3F800000,%fp0
 370
 371        fmovel          %d1,%FPCR               |restore users exceptions
 372        fsubs           #0x00800000,%fp0        |last inst - possible exception set
 373        bra             t_frcinx
 374
 375
 376REDUCEX:
 377|--WHEN REDUCEX IS USED, THE CODE WILL INEVITABLY BE SLOW.
 378|--THIS REDUCTION METHOD, HOWEVER, IS MUCH FASTER THAN USING
 379|--THE REMAINDER INSTRUCTION WHICH IS NOW IN SOFTWARE.
 380
 381        fmovemx %fp2-%fp5,-(%a7)        | ...save FP2 through FP5
 382        movel           %d2,-(%a7)
 383        fmoves         #0x00000000,%fp1
 384|--If compact form of abs(arg) in d0=$7ffeffff, argument is so large that
 385|--there is a danger of unwanted overflow in first LOOP iteration.  In this
 386|--case, reduce argument by one remainder step to make subsequent reduction
 387|--safe.
 388        cmpil   #0x7ffeffff,%d0         |is argument dangerously large?
 389        bnes    LOOP
 390        movel   #0x7ffe0000,FP_SCR2(%a6)        |yes
 391|                                       ;create 2**16383*PI/2
 392        movel   #0xc90fdaa2,FP_SCR2+4(%a6)
 393        clrl    FP_SCR2+8(%a6)
 394        ftstx   %fp0                    |test sign of argument
 395        movel   #0x7fdc0000,FP_SCR3(%a6)        |create low half of 2**16383*
 396|                                       ;PI/2 at FP_SCR3
 397        movel   #0x85a308d3,FP_SCR3+4(%a6)
 398        clrl   FP_SCR3+8(%a6)
 399        fblt    red_neg
 400        orw     #0x8000,FP_SCR2(%a6)    |positive arg
 401        orw     #0x8000,FP_SCR3(%a6)
 402red_neg:
 403        faddx  FP_SCR2(%a6),%fp0                |high part of reduction is exact
 404        fmovex  %fp0,%fp1               |save high result in fp1
 405        faddx  FP_SCR3(%a6),%fp0                |low part of reduction
 406        fsubx  %fp0,%fp1                        |determine low component of result
 407        faddx  FP_SCR3(%a6),%fp1                |fp0/fp1 are reduced argument.
 408
 409|--ON ENTRY, FP0 IS X, ON RETURN, FP0 IS X REM PI/2, |X| <= PI/4.
 410|--integer quotient will be stored in N
 411|--Intermediate remainder is 66-bit long; (R,r) in (FP0,FP1)
 412
 413LOOP:
 414        fmovex          %fp0,INARG(%a6) | ...+-2**K * F, 1 <= F < 2
 415        movew           INARG(%a6),%d0
 416        movel          %d0,%a1          | ...save a copy of D0
 417        andil           #0x00007FFF,%d0
 418        subil           #0x00003FFF,%d0 | ...D0 IS K
 419        cmpil           #28,%d0
 420        bles            LASTLOOP
 421CONTLOOP:
 422        subil           #27,%d0  | ...D0 IS L := K-27
 423        movel           #0,ENDFLAG(%a6)
 424        bras            WORK
 425LASTLOOP:
 426        clrl            %d0             | ...D0 IS L := 0
 427        movel           #1,ENDFLAG(%a6)
 428
 429WORK:
 430|--FIND THE REMAINDER OF (R,r) W.R.T.   2**L * (PI/2). L IS SO CHOSEN
 431|--THAT INT( X * (2/PI) / 2**(L) ) < 2**29.
 432
 433|--CREATE 2**(-L) * (2/PI), SIGN(INARG)*2**(63),
 434|--2**L * (PIby2_1), 2**L * (PIby2_2)
 435
 436        movel           #0x00003FFE,%d2 | ...BIASED EXPO OF 2/PI
 437        subl            %d0,%d2         | ...BIASED EXPO OF 2**(-L)*(2/PI)
 438
 439        movel           #0xA2F9836E,FP_SCR1+4(%a6)
 440        movel           #0x4E44152A,FP_SCR1+8(%a6)
 441        movew           %d2,FP_SCR1(%a6)        | ...FP_SCR1 is 2**(-L)*(2/PI)
 442
 443        fmovex          %fp0,%fp2
 444        fmulx           FP_SCR1(%a6),%fp2
 445|--WE MUST NOW FIND INT(FP2). SINCE WE NEED THIS VALUE IN
 446|--FLOATING POINT FORMAT, THE TWO FMOVE'S       FMOVE.L FP <--> N
 447|--WILL BE TOO INEFFICIENT. THE WAY AROUND IT IS THAT
 448|--(SIGN(INARG)*2**63   +       FP2) - SIGN(INARG)*2**63 WILL GIVE
 449|--US THE DESIRED VALUE IN FLOATING POINT.
 450
 451|--HIDE SIX CYCLES OF INSTRUCTION
 452        movel           %a1,%d2
 453        swap            %d2
 454        andil           #0x80000000,%d2
 455        oril            #0x5F000000,%d2 | ...D2 IS SIGN(INARG)*2**63 IN SGL
 456        movel           %d2,TWOTO63(%a6)
 457
 458        movel           %d0,%d2
 459        addil           #0x00003FFF,%d2 | ...BIASED EXPO OF 2**L * (PI/2)
 460
 461|--FP2 IS READY
 462        fadds           TWOTO63(%a6),%fp2       | ...THE FRACTIONAL PART OF FP1 IS ROUNDED
 463
 464|--HIDE 4 CYCLES OF INSTRUCTION; creating 2**(L)*Piby2_1  and  2**(L)*Piby2_2
 465        movew           %d2,FP_SCR2(%a6)
 466        clrw           FP_SCR2+2(%a6)
 467        movel           #0xC90FDAA2,FP_SCR2+4(%a6)
 468        clrl            FP_SCR2+8(%a6)          | ...FP_SCR2 is  2**(L) * Piby2_1
 469
 470|--FP2 IS READY
 471        fsubs           TWOTO63(%a6),%fp2               | ...FP2 is N
 472
 473        addil           #0x00003FDD,%d0
 474        movew           %d0,FP_SCR3(%a6)
 475        clrw           FP_SCR3+2(%a6)
 476        movel           #0x85A308D3,FP_SCR3+4(%a6)
 477        clrl            FP_SCR3+8(%a6)          | ...FP_SCR3 is 2**(L) * Piby2_2
 478
 479        movel           ENDFLAG(%a6),%d0
 480
 481|--We are now ready to perform (R+r) - N*P1 - N*P2, P1 = 2**(L) * Piby2_1 and
 482|--P2 = 2**(L) * Piby2_2
 483        fmovex          %fp2,%fp4
 484        fmulx           FP_SCR2(%a6),%fp4               | ...W = N*P1
 485        fmovex          %fp2,%fp5
 486        fmulx           FP_SCR3(%a6),%fp5               | ...w = N*P2
 487        fmovex          %fp4,%fp3
 488|--we want P+p = W+w  but  |p| <= half ulp of P
 489|--Then, we need to compute  A := R-P   and  a := r-p
 490        faddx           %fp5,%fp3                       | ...FP3 is P
 491        fsubx           %fp3,%fp4                       | ...W-P
 492
 493        fsubx           %fp3,%fp0                       | ...FP0 is A := R - P
 494        faddx           %fp5,%fp4                       | ...FP4 is p = (W-P)+w
 495
 496        fmovex          %fp0,%fp3                       | ...FP3 A
 497        fsubx           %fp4,%fp1                       | ...FP1 is a := r - p
 498
 499|--Now we need to normalize (A,a) to  "new (R,r)" where R+r = A+a but
 500|--|r| <= half ulp of R.
 501        faddx           %fp1,%fp0                       | ...FP0 is R := A+a
 502|--No need to calculate r if this is the last loop
 503        cmpil           #0,%d0
 504        bgt             RESTORE
 505
 506|--Need to calculate r
 507        fsubx           %fp0,%fp3                       | ...A-R
 508        faddx           %fp3,%fp1                       | ...FP1 is r := (A-R)+a
 509        bra             LOOP
 510
 511RESTORE:
 512        fmovel          %fp2,N(%a6)
 513        movel           (%a7)+,%d2
 514        fmovemx (%a7)+,%fp2-%fp5
 515
 516
 517        movel           ADJN(%a6),%d0
 518        cmpil           #4,%d0
 519
 520        blt             SINCONT
 521        bras            SCCONT
 522
 523        .global ssincosd
 524ssincosd:
 525|--SIN AND COS OF X FOR DENORMALIZED X
 526
 527        fmoves          #0x3F800000,%fp1
 528        bsr             sto_cos         |store cosine result
 529        bra             t_extdnrm
 530
 531        .global ssincos
 532ssincos:
 533|--SET ADJN TO 4
 534        movel           #4,ADJN(%a6)
 535
 536        fmovex          (%a0),%fp0      | ...LOAD INPUT
 537
 538        movel           (%a0),%d0
 539        movew           4(%a0),%d0
 540        fmovex          %fp0,X(%a6)
 541        andil           #0x7FFFFFFF,%d0         | ...COMPACTIFY X
 542
 543        cmpil           #0x3FD78000,%d0         | ...|X| >= 2**(-40)?
 544        bges            SCOK1
 545        bra             SCSM
 546
 547SCOK1:
 548        cmpil           #0x4004BC7E,%d0         | ...|X| < 15 PI?
 549        blts            SCMAIN
 550        bra             REDUCEX
 551
 552
 553SCMAIN:
 554|--THIS IS THE USUAL CASE, |X| <= 15 PI.
 555|--THE ARGUMENT REDUCTION IS DONE BY TABLE LOOK UP.
 556        fmovex          %fp0,%fp1
 557        fmuld           TWOBYPI,%fp1    | ...X*2/PI
 558
 559|--HIDE THE NEXT THREE INSTRUCTIONS
 560        lea             PITBL+0x200,%a1 | ...TABLE OF N*PI/2, N = -32,...,32
 561
 562
 563|--FP1 IS NOW READY
 564        fmovel          %fp1,N(%a6)             | ...CONVERT TO INTEGER
 565
 566        movel           N(%a6),%d0
 567        asll            #4,%d0
 568        addal           %d0,%a1         | ...ADDRESS OF N*PIBY2, IN Y1, Y2
 569
 570        fsubx           (%a1)+,%fp0     | ...X-Y1
 571        fsubs           (%a1),%fp0      | ...FP0 IS R = (X-Y1)-Y2
 572
 573SCCONT:
 574|--continuation point from REDUCEX
 575
 576|--HIDE THE NEXT TWO
 577        movel           N(%a6),%d0
 578        rorl            #1,%d0
 579
 580        cmpil           #0,%d0          | ...D0 < 0 IFF N IS ODD
 581        bge             NEVEN
 582
 583NODD:
 584|--REGISTERS SAVED SO FAR: D0, A0, FP2.
 585
 586        fmovex          %fp0,RPRIME(%a6)
 587        fmulx           %fp0,%fp0        | ...FP0 IS S = R*R
 588        fmoved          SINA7,%fp1      | ...A7
 589        fmoved          COSB8,%fp2      | ...B8
 590        fmulx           %fp0,%fp1        | ...SA7
 591        movel           %d2,-(%a7)
 592        movel           %d0,%d2
 593        fmulx           %fp0,%fp2        | ...SB8
 594        rorl            #1,%d2
 595        andil           #0x80000000,%d2
 596
 597        faddd           SINA6,%fp1      | ...A6+SA7
 598        eorl            %d0,%d2
 599        andil           #0x80000000,%d2
 600        faddd           COSB7,%fp2      | ...B7+SB8
 601
 602        fmulx           %fp0,%fp1        | ...S(A6+SA7)
 603        eorl            %d2,RPRIME(%a6)
 604        movel           (%a7)+,%d2
 605        fmulx           %fp0,%fp2        | ...S(B7+SB8)
 606        rorl            #1,%d0
 607        andil           #0x80000000,%d0
 608
 609        faddd           SINA5,%fp1      | ...A5+S(A6+SA7)
 610        movel           #0x3F800000,POSNEG1(%a6)
 611        eorl            %d0,POSNEG1(%a6)
 612        faddd           COSB6,%fp2      | ...B6+S(B7+SB8)
 613
 614        fmulx           %fp0,%fp1        | ...S(A5+S(A6+SA7))
 615        fmulx           %fp0,%fp2        | ...S(B6+S(B7+SB8))
 616        fmovex          %fp0,SPRIME(%a6)
 617
 618        faddd           SINA4,%fp1      | ...A4+S(A5+S(A6+SA7))
 619        eorl            %d0,SPRIME(%a6)
 620        faddd           COSB5,%fp2      | ...B5+S(B6+S(B7+SB8))
 621
 622        fmulx           %fp0,%fp1        | ...S(A4+...)
 623        fmulx           %fp0,%fp2        | ...S(B5+...)
 624
 625        faddd           SINA3,%fp1      | ...A3+S(A4+...)
 626        faddd           COSB4,%fp2      | ...B4+S(B5+...)
 627
 628        fmulx           %fp0,%fp1        | ...S(A3+...)
 629        fmulx           %fp0,%fp2        | ...S(B4+...)
 630
 631        faddx           SINA2,%fp1      | ...A2+S(A3+...)
 632        faddx           COSB3,%fp2      | ...B3+S(B4+...)
 633
 634        fmulx           %fp0,%fp1        | ...S(A2+...)
 635        fmulx           %fp0,%fp2        | ...S(B3+...)
 636
 637        faddx           SINA1,%fp1      | ...A1+S(A2+...)
 638        faddx           COSB2,%fp2      | ...B2+S(B3+...)
 639
 640        fmulx           %fp0,%fp1        | ...S(A1+...)
 641        fmulx           %fp2,%fp0        | ...S(B2+...)
 642
 643
 644
 645        fmulx           RPRIME(%a6),%fp1        | ...R'S(A1+...)
 646        fadds           COSB1,%fp0      | ...B1+S(B2...)
 647        fmulx           SPRIME(%a6),%fp0        | ...S'(B1+S(B2+...))
 648
 649        movel           %d1,-(%sp)      |restore users mode & precision
 650        andil           #0xff,%d1               |mask off all exceptions
 651        fmovel          %d1,%FPCR
 652        faddx           RPRIME(%a6),%fp1        | ...COS(X)
 653        bsr             sto_cos         |store cosine result
 654        fmovel          (%sp)+,%FPCR    |restore users exceptions
 655        fadds           POSNEG1(%a6),%fp0       | ...SIN(X)
 656
 657        bra             t_frcinx
 658
 659
 660NEVEN:
 661|--REGISTERS SAVED SO FAR: FP2.
 662
 663        fmovex          %fp0,RPRIME(%a6)
 664        fmulx           %fp0,%fp0        | ...FP0 IS S = R*R
 665        fmoved          COSB8,%fp1                      | ...B8
 666        fmoved          SINA7,%fp2                      | ...A7
 667        fmulx           %fp0,%fp1        | ...SB8
 668        fmovex          %fp0,SPRIME(%a6)
 669        fmulx           %fp0,%fp2        | ...SA7
 670        rorl            #1,%d0
 671        andil           #0x80000000,%d0
 672        faddd           COSB7,%fp1      | ...B7+SB8
 673        faddd           SINA6,%fp2      | ...A6+SA7
 674        eorl            %d0,RPRIME(%a6)
 675        eorl            %d0,SPRIME(%a6)
 676        fmulx           %fp0,%fp1        | ...S(B7+SB8)
 677        oril            #0x3F800000,%d0
 678        movel           %d0,POSNEG1(%a6)
 679        fmulx           %fp0,%fp2        | ...S(A6+SA7)
 680
 681        faddd           COSB6,%fp1      | ...B6+S(B7+SB8)
 682        faddd           SINA5,%fp2      | ...A5+S(A6+SA7)
 683
 684        fmulx           %fp0,%fp1        | ...S(B6+S(B7+SB8))
 685        fmulx           %fp0,%fp2        | ...S(A5+S(A6+SA7))
 686
 687        faddd           COSB5,%fp1      | ...B5+S(B6+S(B7+SB8))
 688        faddd           SINA4,%fp2      | ...A4+S(A5+S(A6+SA7))
 689
 690        fmulx           %fp0,%fp1        | ...S(B5+...)
 691        fmulx           %fp0,%fp2        | ...S(A4+...)
 692
 693        faddd           COSB4,%fp1      | ...B4+S(B5+...)
 694        faddd           SINA3,%fp2      | ...A3+S(A4+...)
 695
 696        fmulx           %fp0,%fp1        | ...S(B4+...)
 697        fmulx           %fp0,%fp2        | ...S(A3+...)
 698
 699        faddx           COSB3,%fp1      | ...B3+S(B4+...)
 700        faddx           SINA2,%fp2      | ...A2+S(A3+...)
 701
 702        fmulx           %fp0,%fp1        | ...S(B3+...)
 703        fmulx           %fp0,%fp2        | ...S(A2+...)
 704
 705        faddx           COSB2,%fp1      | ...B2+S(B3+...)
 706        faddx           SINA1,%fp2      | ...A1+S(A2+...)
 707
 708        fmulx           %fp0,%fp1        | ...S(B2+...)
 709        fmulx           %fp2,%fp0        | ...s(a1+...)
 710
 711
 712
 713        fadds           COSB1,%fp1      | ...B1+S(B2...)
 714        fmulx           RPRIME(%a6),%fp0        | ...R'S(A1+...)
 715        fmulx           SPRIME(%a6),%fp1        | ...S'(B1+S(B2+...))
 716
 717        movel           %d1,-(%sp)      |save users mode & precision
 718        andil           #0xff,%d1               |mask off all exceptions
 719        fmovel          %d1,%FPCR
 720        fadds           POSNEG1(%a6),%fp1       | ...COS(X)
 721        bsr             sto_cos         |store cosine result
 722        fmovel          (%sp)+,%FPCR    |restore users exceptions
 723        faddx           RPRIME(%a6),%fp0        | ...SIN(X)
 724
 725        bra             t_frcinx
 726
 727SCBORS:
 728        cmpil           #0x3FFF8000,%d0
 729        bgt             REDUCEX
 730
 731
 732SCSM:
 733        movew           #0x0000,XDCARE(%a6)
 734        fmoves          #0x3F800000,%fp1
 735
 736        movel           %d1,-(%sp)      |save users mode & precision
 737        andil           #0xff,%d1               |mask off all exceptions
 738        fmovel          %d1,%FPCR
 739        fsubs           #0x00800000,%fp1
 740        bsr             sto_cos         |store cosine result
 741        fmovel          (%sp)+,%FPCR    |restore users exceptions
 742        fmovex          X(%a6),%fp0
 743        bra             t_frcinx
 744
 745        |end
 746