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1 734 jeremybenn
/* Assembly functions for the Xtensa version of libgcc1.
2
   Copyright (C) 2001, 2002, 2003, 2005, 2006, 2007, 2009
3
   Free Software Foundation, Inc.
4
   Contributed by Bob Wilson (bwilson@tensilica.com) at Tensilica.
5
 
6
This file is part of GCC.
7
 
8
GCC is free software; you can redistribute it and/or modify it under
9
the terms of the GNU General Public License as published by the Free
10
Software Foundation; either version 3, or (at your option) any later
11
version.
12
 
13
GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14
WARRANTY; without even the implied warranty of MERCHANTABILITY or
15
FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
16
for more details.
17
 
18
Under Section 7 of GPL version 3, you are granted additional
19
permissions described in the GCC Runtime Library Exception, version
20
3.1, as published by the Free Software Foundation.
21
 
22
You should have received a copy of the GNU General Public License and
23
a copy of the GCC Runtime Library Exception along with this program;
24
see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
25
.  */
26
 
27
#include "xtensa-config.h"
28
 
29
/* Define macros for the ABS and ADDX* instructions to handle cases
30
   where they are not included in the Xtensa processor configuration.  */
31
 
32
        .macro  do_abs dst, src, tmp
33
#if XCHAL_HAVE_ABS
34
        abs     \dst, \src
35
#else
36
        neg     \tmp, \src
37
        movgez  \tmp, \src, \src
38
        mov     \dst, \tmp
39
#endif
40
        .endm
41
 
42
        .macro  do_addx2 dst, as, at, tmp
43
#if XCHAL_HAVE_ADDX
44
        addx2   \dst, \as, \at
45
#else
46
        slli    \tmp, \as, 1
47
        add     \dst, \tmp, \at
48
#endif
49
        .endm
50
 
51
        .macro  do_addx4 dst, as, at, tmp
52
#if XCHAL_HAVE_ADDX
53
        addx4   \dst, \as, \at
54
#else
55
        slli    \tmp, \as, 2
56
        add     \dst, \tmp, \at
57
#endif
58
        .endm
59
 
60
        .macro  do_addx8 dst, as, at, tmp
61
#if XCHAL_HAVE_ADDX
62
        addx8   \dst, \as, \at
63
#else
64
        slli    \tmp, \as, 3
65
        add     \dst, \tmp, \at
66
#endif
67
        .endm
68
 
69
/* Define macros for leaf function entry and return, supporting either the
70
   standard register windowed ABI or the non-windowed call0 ABI.  These
71
   macros do not allocate any extra stack space, so they only work for
72
   leaf functions that do not need to spill anything to the stack.  */
73
 
74
        .macro leaf_entry reg, size
75
#if XCHAL_HAVE_WINDOWED && !__XTENSA_CALL0_ABI__
76
        entry \reg, \size
77
#else
78
        /* do nothing */
79
#endif
80
        .endm
81
 
82
        .macro leaf_return
83
#if XCHAL_HAVE_WINDOWED && !__XTENSA_CALL0_ABI__
84
        retw
85
#else
86
        ret
87
#endif
88
        .endm
89
 
90
 
91
#ifdef L_mulsi3
92
        .align  4
93
        .global __mulsi3
94
        .type   __mulsi3, @function
95
__mulsi3:
96
        leaf_entry sp, 16
97
 
98
#if XCHAL_HAVE_MUL32
99
        mull    a2, a2, a3
100
 
101
#elif XCHAL_HAVE_MUL16
102
        or      a4, a2, a3
103
        srai    a4, a4, 16
104
        bnez    a4, .LMUL16
105
        mul16u  a2, a2, a3
106
        leaf_return
107
.LMUL16:
108
        srai    a4, a2, 16
109
        srai    a5, a3, 16
110
        mul16u  a7, a4, a3
111
        mul16u  a6, a5, a2
112
        mul16u  a4, a2, a3
113
        add     a7, a7, a6
114
        slli    a7, a7, 16
115
        add     a2, a7, a4
116
 
117
#elif XCHAL_HAVE_MAC16
118
        mul.aa.hl a2, a3
119
        mula.aa.lh a2, a3
120
        rsr     a5, ACCLO
121
        umul.aa.ll a2, a3
122
        rsr     a4, ACCLO
123
        slli    a5, a5, 16
124
        add     a2, a4, a5
125
 
126
#else /* !MUL32 && !MUL16 && !MAC16 */
127
 
128
        /* Multiply one bit at a time, but unroll the loop 4x to better
129
           exploit the addx instructions and avoid overhead.
130
           Peel the first iteration to save a cycle on init.  */
131
 
132
        /* Avoid negative numbers.  */
133
        xor     a5, a2, a3      /* Top bit is 1 if one input is negative.  */
134
        do_abs  a3, a3, a6
135
        do_abs  a2, a2, a6
136
 
137
        /* Swap so the second argument is smaller.  */
138
        sub     a7, a2, a3
139
        mov     a4, a3
140
        movgez  a4, a2, a7      /* a4 = max (a2, a3) */
141
        movltz  a3, a2, a7      /* a3 = min (a2, a3) */
142
 
143
        movi    a2, 0
144
        extui   a6, a3, 0, 1
145
        movnez  a2, a4, a6
146
 
147
        do_addx2 a7, a4, a2, a7
148
        extui   a6, a3, 1, 1
149
        movnez  a2, a7, a6
150
 
151
        do_addx4 a7, a4, a2, a7
152
        extui   a6, a3, 2, 1
153
        movnez  a2, a7, a6
154
 
155
        do_addx8 a7, a4, a2, a7
156
        extui   a6, a3, 3, 1
157
        movnez  a2, a7, a6
158
 
159
        bgeui   a3, 16, .Lmult_main_loop
160
        neg     a3, a2
161
        movltz  a2, a3, a5
162
        leaf_return
163
 
164
        .align  4
165
.Lmult_main_loop:
166
        srli    a3, a3, 4
167
        slli    a4, a4, 4
168
 
169
        add     a7, a4, a2
170
        extui   a6, a3, 0, 1
171
        movnez  a2, a7, a6
172
 
173
        do_addx2 a7, a4, a2, a7
174
        extui   a6, a3, 1, 1
175
        movnez  a2, a7, a6
176
 
177
        do_addx4 a7, a4, a2, a7
178
        extui   a6, a3, 2, 1
179
        movnez  a2, a7, a6
180
 
181
        do_addx8 a7, a4, a2, a7
182
        extui   a6, a3, 3, 1
183
        movnez  a2, a7, a6
184
 
185
        bgeui   a3, 16, .Lmult_main_loop
186
 
187
        neg     a3, a2
188
        movltz  a2, a3, a5
189
 
190
#endif /* !MUL32 && !MUL16 && !MAC16 */
191
 
192
        leaf_return
193
        .size   __mulsi3, . - __mulsi3
194
 
195
#endif /* L_mulsi3 */
196
 
197
 
198
#ifdef L_umulsidi3
199
 
200
#if !XCHAL_HAVE_MUL16 && !XCHAL_HAVE_MUL32 && !XCHAL_HAVE_MAC16
201
#define XCHAL_NO_MUL 1
202
#endif
203
 
204
        .align  4
205
        .global __umulsidi3
206
        .type   __umulsidi3, @function
207
__umulsidi3:
208
#if __XTENSA_CALL0_ABI__
209
        leaf_entry sp, 32
210
        addi    sp, sp, -32
211
        s32i    a12, sp, 16
212
        s32i    a13, sp, 20
213
        s32i    a14, sp, 24
214
        s32i    a15, sp, 28
215
#elif XCHAL_NO_MUL
216
        /* This is not really a leaf function; allocate enough stack space
217
           to allow CALL12s to a helper function.  */
218
        leaf_entry sp, 48
219
#else
220
        leaf_entry sp, 16
221
#endif
222
 
223
#ifdef __XTENSA_EB__
224
#define wh a2
225
#define wl a3
226
#else
227
#define wh a3
228
#define wl a2
229
#endif /* __XTENSA_EB__ */
230
 
231
        /* This code is taken from the mulsf3 routine in ieee754-sf.S.
232
           See more comments there.  */
233
 
234
#if XCHAL_HAVE_MUL32_HIGH
235
        mull    a6, a2, a3
236
        muluh   wh, a2, a3
237
        mov     wl, a6
238
 
239
#else /* ! MUL32_HIGH */
240
 
241
#if __XTENSA_CALL0_ABI__ && XCHAL_NO_MUL
242
        /* a0 and a8 will be clobbered by calling the multiply function
243
           but a8 is not used here and need not be saved.  */
244
        s32i    a0, sp, 0
245
#endif
246
 
247
#if XCHAL_HAVE_MUL16 || XCHAL_HAVE_MUL32
248
 
249
#define a2h a4
250
#define a3h a5
251
 
252
        /* Get the high halves of the inputs into registers.  */
253
        srli    a2h, a2, 16
254
        srli    a3h, a3, 16
255
 
256
#define a2l a2
257
#define a3l a3
258
 
259
#if XCHAL_HAVE_MUL32 && !XCHAL_HAVE_MUL16
260
        /* Clear the high halves of the inputs.  This does not matter
261
           for MUL16 because the high bits are ignored.  */
262
        extui   a2, a2, 0, 16
263
        extui   a3, a3, 0, 16
264
#endif
265
#endif /* MUL16 || MUL32 */
266
 
267
 
268
#if XCHAL_HAVE_MUL16
269
 
270
#define do_mul(dst, xreg, xhalf, yreg, yhalf) \
271
        mul16u  dst, xreg ## xhalf, yreg ## yhalf
272
 
273
#elif XCHAL_HAVE_MUL32
274
 
275
#define do_mul(dst, xreg, xhalf, yreg, yhalf) \
276
        mull    dst, xreg ## xhalf, yreg ## yhalf
277
 
278
#elif XCHAL_HAVE_MAC16
279
 
280
/* The preprocessor insists on inserting a space when concatenating after
281
   a period in the definition of do_mul below.  These macros are a workaround
282
   using underscores instead of periods when doing the concatenation.  */
283
#define umul_aa_ll umul.aa.ll
284
#define umul_aa_lh umul.aa.lh
285
#define umul_aa_hl umul.aa.hl
286
#define umul_aa_hh umul.aa.hh
287
 
288
#define do_mul(dst, xreg, xhalf, yreg, yhalf) \
289
        umul_aa_ ## xhalf ## yhalf      xreg, yreg; \
290
        rsr     dst, ACCLO
291
 
292
#else /* no multiply hardware */
293
 
294
#define set_arg_l(dst, src) \
295
        extui   dst, src, 0, 16
296
#define set_arg_h(dst, src) \
297
        srli    dst, src, 16
298
 
299
#if __XTENSA_CALL0_ABI__
300
#define do_mul(dst, xreg, xhalf, yreg, yhalf) \
301
        set_arg_ ## xhalf (a13, xreg); \
302
        set_arg_ ## yhalf (a14, yreg); \
303
        call0   .Lmul_mulsi3; \
304
        mov     dst, a12
305
#else
306
#define do_mul(dst, xreg, xhalf, yreg, yhalf) \
307
        set_arg_ ## xhalf (a14, xreg); \
308
        set_arg_ ## yhalf (a15, yreg); \
309
        call12  .Lmul_mulsi3; \
310
        mov     dst, a14
311
#endif /* __XTENSA_CALL0_ABI__ */
312
 
313
#endif /* no multiply hardware */
314
 
315
        /* Add pp1 and pp2 into a6 with carry-out in a9.  */
316
        do_mul(a6, a2, l, a3, h)        /* pp 1 */
317
        do_mul(a11, a2, h, a3, l)       /* pp 2 */
318
        movi    a9, 0
319
        add     a6, a6, a11
320
        bgeu    a6, a11, 1f
321
        addi    a9, a9, 1
322
1:
323
        /* Shift the high half of a9/a6 into position in a9.  Note that
324
           this value can be safely incremented without any carry-outs.  */
325
        ssai    16
326
        src     a9, a9, a6
327
 
328
        /* Compute the low word into a6.  */
329
        do_mul(a11, a2, l, a3, l)       /* pp 0 */
330
        sll     a6, a6
331
        add     a6, a6, a11
332
        bgeu    a6, a11, 1f
333
        addi    a9, a9, 1
334
1:
335
        /* Compute the high word into wh.  */
336
        do_mul(wh, a2, h, a3, h)        /* pp 3 */
337
        add     wh, wh, a9
338
        mov     wl, a6
339
 
340
#endif /* !MUL32_HIGH */
341
 
342
#if __XTENSA_CALL0_ABI__ && XCHAL_NO_MUL
343
        /* Restore the original return address.  */
344
        l32i    a0, sp, 0
345
#endif
346
#if __XTENSA_CALL0_ABI__
347
        l32i    a12, sp, 16
348
        l32i    a13, sp, 20
349
        l32i    a14, sp, 24
350
        l32i    a15, sp, 28
351
        addi    sp, sp, 32
352
#endif
353
        leaf_return
354
 
355
#if XCHAL_NO_MUL
356
 
357
        /* For Xtensa processors with no multiply hardware, this simplified
358
           version of _mulsi3 is used for multiplying 16-bit chunks of
359
           the floating-point mantissas.  When using CALL0, this function
360
           uses a custom ABI: the inputs are passed in a13 and a14, the
361
           result is returned in a12, and a8 and a15 are clobbered.  */
362
        .align  4
363
.Lmul_mulsi3:
364
        leaf_entry sp, 16
365
        .macro mul_mulsi3_body dst, src1, src2, tmp1, tmp2
366
        movi    \dst, 0
367
1:      add     \tmp1, \src2, \dst
368
        extui   \tmp2, \src1, 0, 1
369
        movnez  \dst, \tmp1, \tmp2
370
 
371
        do_addx2 \tmp1, \src2, \dst, \tmp1
372
        extui   \tmp2, \src1, 1, 1
373
        movnez  \dst, \tmp1, \tmp2
374
 
375
        do_addx4 \tmp1, \src2, \dst, \tmp1
376
        extui   \tmp2, \src1, 2, 1
377
        movnez  \dst, \tmp1, \tmp2
378
 
379
        do_addx8 \tmp1, \src2, \dst, \tmp1
380
        extui   \tmp2, \src1, 3, 1
381
        movnez  \dst, \tmp1, \tmp2
382
 
383
        srli    \src1, \src1, 4
384
        slli    \src2, \src2, 4
385
        bnez    \src1, 1b
386
        .endm
387
#if __XTENSA_CALL0_ABI__
388
        mul_mulsi3_body a12, a13, a14, a15, a8
389
#else
390
        /* The result will be written into a2, so save that argument in a4.  */
391
        mov     a4, a2
392
        mul_mulsi3_body a2, a4, a3, a5, a6
393
#endif
394
        leaf_return
395
#endif /* XCHAL_NO_MUL */
396
 
397
        .size   __umulsidi3, . - __umulsidi3
398
 
399
#endif /* L_umulsidi3 */
400
 
401
 
402
/* Define a macro for the NSAU (unsigned normalize shift amount)
403
   instruction, which computes the number of leading zero bits,
404
   to handle cases where it is not included in the Xtensa processor
405
   configuration.  */
406
 
407
        .macro  do_nsau cnt, val, tmp, a
408
#if XCHAL_HAVE_NSA
409
        nsau    \cnt, \val
410
#else
411
        mov     \a, \val
412
        movi    \cnt, 0
413
        extui   \tmp, \a, 16, 16
414
        bnez    \tmp, 0f
415
        movi    \cnt, 16
416
        slli    \a, \a, 16
417
0:
418
        extui   \tmp, \a, 24, 8
419
        bnez    \tmp, 1f
420
        addi    \cnt, \cnt, 8
421
        slli    \a, \a, 8
422
1:
423
        movi    \tmp, __nsau_data
424
        extui   \a, \a, 24, 8
425
        add     \tmp, \tmp, \a
426
        l8ui    \tmp, \tmp, 0
427
        add     \cnt, \cnt, \tmp
428
#endif /* !XCHAL_HAVE_NSA */
429
        .endm
430
 
431
#ifdef L_clz
432
        .section .rodata
433
        .align  4
434
        .global __nsau_data
435
        .type   __nsau_data, @object
436
__nsau_data:
437
#if !XCHAL_HAVE_NSA
438
        .byte   8, 7, 6, 6, 5, 5, 5, 5, 4, 4, 4, 4, 4, 4, 4, 4
439
        .byte   3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3
440
        .byte   2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2
441
        .byte   2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2
442
        .byte   1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1
443
        .byte   1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1
444
        .byte   1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1
445
        .byte   1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1
446
        .byte   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
447
        .byte   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
448
        .byte   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
449
        .byte   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
450
        .byte   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
451
        .byte   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
452
        .byte   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
453
        .byte   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
454
#endif /* !XCHAL_HAVE_NSA */
455
        .size   __nsau_data, . - __nsau_data
456
        .hidden __nsau_data
457
#endif /* L_clz */
458
 
459
 
460
#ifdef L_clzsi2
461
        .align  4
462
        .global __clzsi2
463
        .type   __clzsi2, @function
464
__clzsi2:
465
        leaf_entry sp, 16
466
        do_nsau a2, a2, a3, a4
467
        leaf_return
468
        .size   __clzsi2, . - __clzsi2
469
 
470
#endif /* L_clzsi2 */
471
 
472
 
473
#ifdef L_ctzsi2
474
        .align  4
475
        .global __ctzsi2
476
        .type   __ctzsi2, @function
477
__ctzsi2:
478
        leaf_entry sp, 16
479
        neg     a3, a2
480
        and     a3, a3, a2
481
        do_nsau a2, a3, a4, a5
482
        neg     a2, a2
483
        addi    a2, a2, 31
484
        leaf_return
485
        .size   __ctzsi2, . - __ctzsi2
486
 
487
#endif /* L_ctzsi2 */
488
 
489
 
490
#ifdef L_ffssi2
491
        .align  4
492
        .global __ffssi2
493
        .type   __ffssi2, @function
494
__ffssi2:
495
        leaf_entry sp, 16
496
        neg     a3, a2
497
        and     a3, a3, a2
498
        do_nsau a2, a3, a4, a5
499
        neg     a2, a2
500
        addi    a2, a2, 32
501
        leaf_return
502
        .size   __ffssi2, . - __ffssi2
503
 
504
#endif /* L_ffssi2 */
505
 
506
 
507
#ifdef L_udivsi3
508
        .align  4
509
        .global __udivsi3
510
        .type   __udivsi3, @function
511
__udivsi3:
512
        leaf_entry sp, 16
513
#if XCHAL_HAVE_DIV32
514
        quou    a2, a2, a3
515
#else
516
        bltui   a3, 2, .Lle_one /* check if the divisor <= 1 */
517
 
518
        mov     a6, a2          /* keep dividend in a6 */
519
        do_nsau a5, a6, a2, a7  /* dividend_shift = nsau (dividend) */
520
        do_nsau a4, a3, a2, a7  /* divisor_shift = nsau (divisor) */
521
        bgeu    a5, a4, .Lspecial
522
 
523
        sub     a4, a4, a5      /* count = divisor_shift - dividend_shift */
524
        ssl     a4
525
        sll     a3, a3          /* divisor <<= count */
526
        movi    a2, 0           /* quotient = 0 */
527
 
528
        /* test-subtract-and-shift loop; one quotient bit on each iteration */
529
#if XCHAL_HAVE_LOOPS
530
        loopnez a4, .Lloopend
531
#endif /* XCHAL_HAVE_LOOPS */
532
.Lloop:
533
        bltu    a6, a3, .Lzerobit
534
        sub     a6, a6, a3
535
        addi    a2, a2, 1
536
.Lzerobit:
537
        slli    a2, a2, 1
538
        srli    a3, a3, 1
539
#if !XCHAL_HAVE_LOOPS
540
        addi    a4, a4, -1
541
        bnez    a4, .Lloop
542
#endif /* !XCHAL_HAVE_LOOPS */
543
.Lloopend:
544
 
545
        bltu    a6, a3, .Lreturn
546
        addi    a2, a2, 1       /* increment quotient if dividend >= divisor */
547
.Lreturn:
548
        leaf_return
549
 
550
.Lle_one:
551
        beqz    a3, .Lerror     /* if divisor == 1, return the dividend */
552
        leaf_return
553
 
554
.Lspecial:
555
        /* return dividend >= divisor */
556
        bltu    a6, a3, .Lreturn0
557
        movi    a2, 1
558
        leaf_return
559
 
560
.Lerror:
561
        /* Divide by zero: Use an illegal instruction to force an exception.
562
           The subsequent "DIV0" string can be recognized by the exception
563
           handler to identify the real cause of the exception.  */
564
        ill
565
        .ascii  "DIV0"
566
 
567
.Lreturn0:
568
        movi    a2, 0
569
#endif /* XCHAL_HAVE_DIV32 */
570
        leaf_return
571
        .size   __udivsi3, . - __udivsi3
572
 
573
#endif /* L_udivsi3 */
574
 
575
 
576
#ifdef L_divsi3
577
        .align  4
578
        .global __divsi3
579
        .type   __divsi3, @function
580
__divsi3:
581
        leaf_entry sp, 16
582
#if XCHAL_HAVE_DIV32
583
        quos    a2, a2, a3
584
#else
585
        xor     a7, a2, a3      /* sign = dividend ^ divisor */
586
        do_abs  a6, a2, a4      /* udividend = abs (dividend) */
587
        do_abs  a3, a3, a4      /* udivisor = abs (divisor) */
588
        bltui   a3, 2, .Lle_one /* check if udivisor <= 1 */
589
        do_nsau a5, a6, a2, a8  /* udividend_shift = nsau (udividend) */
590
        do_nsau a4, a3, a2, a8  /* udivisor_shift = nsau (udivisor) */
591
        bgeu    a5, a4, .Lspecial
592
 
593
        sub     a4, a4, a5      /* count = udivisor_shift - udividend_shift */
594
        ssl     a4
595
        sll     a3, a3          /* udivisor <<= count */
596
        movi    a2, 0           /* quotient = 0 */
597
 
598
        /* test-subtract-and-shift loop; one quotient bit on each iteration */
599
#if XCHAL_HAVE_LOOPS
600
        loopnez a4, .Lloopend
601
#endif /* XCHAL_HAVE_LOOPS */
602
.Lloop:
603
        bltu    a6, a3, .Lzerobit
604
        sub     a6, a6, a3
605
        addi    a2, a2, 1
606
.Lzerobit:
607
        slli    a2, a2, 1
608
        srli    a3, a3, 1
609
#if !XCHAL_HAVE_LOOPS
610
        addi    a4, a4, -1
611
        bnez    a4, .Lloop
612
#endif /* !XCHAL_HAVE_LOOPS */
613
.Lloopend:
614
 
615
        bltu    a6, a3, .Lreturn
616
        addi    a2, a2, 1       /* increment if udividend >= udivisor */
617
.Lreturn:
618
        neg     a5, a2
619
        movltz  a2, a5, a7      /* return (sign < 0) ? -quotient : quotient */
620
        leaf_return
621
 
622
.Lle_one:
623
        beqz    a3, .Lerror
624
        neg     a2, a6          /* if udivisor == 1, then return... */
625
        movgez  a2, a6, a7      /* (sign < 0) ? -udividend : udividend */
626
        leaf_return
627
 
628
.Lspecial:
629
        bltu    a6, a3, .Lreturn0 /* if dividend < divisor, return 0 */
630
        movi    a2, 1
631
        movi    a4, -1
632
        movltz  a2, a4, a7      /* else return (sign < 0) ? -1 : 1 */
633
        leaf_return
634
 
635
.Lerror:
636
        /* Divide by zero: Use an illegal instruction to force an exception.
637
           The subsequent "DIV0" string can be recognized by the exception
638
           handler to identify the real cause of the exception.  */
639
        ill
640
        .ascii  "DIV0"
641
 
642
.Lreturn0:
643
        movi    a2, 0
644
#endif /* XCHAL_HAVE_DIV32 */
645
        leaf_return
646
        .size   __divsi3, . - __divsi3
647
 
648
#endif /* L_divsi3 */
649
 
650
 
651
#ifdef L_umodsi3
652
        .align  4
653
        .global __umodsi3
654
        .type   __umodsi3, @function
655
__umodsi3:
656
        leaf_entry sp, 16
657
#if XCHAL_HAVE_DIV32
658
        remu    a2, a2, a3
659
#else
660
        bltui   a3, 2, .Lle_one /* check if the divisor is <= 1 */
661
 
662
        do_nsau a5, a2, a6, a7  /* dividend_shift = nsau (dividend) */
663
        do_nsau a4, a3, a6, a7  /* divisor_shift = nsau (divisor) */
664
        bgeu    a5, a4, .Lspecial
665
 
666
        sub     a4, a4, a5      /* count = divisor_shift - dividend_shift */
667
        ssl     a4
668
        sll     a3, a3          /* divisor <<= count */
669
 
670
        /* test-subtract-and-shift loop */
671
#if XCHAL_HAVE_LOOPS
672
        loopnez a4, .Lloopend
673
#endif /* XCHAL_HAVE_LOOPS */
674
.Lloop:
675
        bltu    a2, a3, .Lzerobit
676
        sub     a2, a2, a3
677
.Lzerobit:
678
        srli    a3, a3, 1
679
#if !XCHAL_HAVE_LOOPS
680
        addi    a4, a4, -1
681
        bnez    a4, .Lloop
682
#endif /* !XCHAL_HAVE_LOOPS */
683
.Lloopend:
684
 
685
.Lspecial:
686
        bltu    a2, a3, .Lreturn
687
        sub     a2, a2, a3      /* subtract once more if dividend >= divisor */
688
.Lreturn:
689
        leaf_return
690
 
691
.Lle_one:
692
        bnez    a3, .Lreturn0
693
 
694
        /* Divide by zero: Use an illegal instruction to force an exception.
695
           The subsequent "DIV0" string can be recognized by the exception
696
           handler to identify the real cause of the exception.  */
697
        ill
698
        .ascii  "DIV0"
699
 
700
.Lreturn0:
701
        movi    a2, 0
702
#endif /* XCHAL_HAVE_DIV32 */
703
        leaf_return
704
        .size   __umodsi3, . - __umodsi3
705
 
706
#endif /* L_umodsi3 */
707
 
708
 
709
#ifdef L_modsi3
710
        .align  4
711
        .global __modsi3
712
        .type   __modsi3, @function
713
__modsi3:
714
        leaf_entry sp, 16
715
#if XCHAL_HAVE_DIV32
716
        rems    a2, a2, a3
717
#else
718
        mov     a7, a2          /* save original (signed) dividend */
719
        do_abs  a2, a2, a4      /* udividend = abs (dividend) */
720
        do_abs  a3, a3, a4      /* udivisor = abs (divisor) */
721
        bltui   a3, 2, .Lle_one /* check if udivisor <= 1 */
722
        do_nsau a5, a2, a6, a8  /* udividend_shift = nsau (udividend) */
723
        do_nsau a4, a3, a6, a8  /* udivisor_shift = nsau (udivisor) */
724
        bgeu    a5, a4, .Lspecial
725
 
726
        sub     a4, a4, a5      /* count = udivisor_shift - udividend_shift */
727
        ssl     a4
728
        sll     a3, a3          /* udivisor <<= count */
729
 
730
        /* test-subtract-and-shift loop */
731
#if XCHAL_HAVE_LOOPS
732
        loopnez a4, .Lloopend
733
#endif /* XCHAL_HAVE_LOOPS */
734
.Lloop:
735
        bltu    a2, a3, .Lzerobit
736
        sub     a2, a2, a3
737
.Lzerobit:
738
        srli    a3, a3, 1
739
#if !XCHAL_HAVE_LOOPS
740
        addi    a4, a4, -1
741
        bnez    a4, .Lloop
742
#endif /* !XCHAL_HAVE_LOOPS */
743
.Lloopend:
744
 
745
.Lspecial:
746
        bltu    a2, a3, .Lreturn
747
        sub     a2, a2, a3      /* subtract again if udividend >= udivisor */
748
.Lreturn:
749
        bgez    a7, .Lpositive
750
        neg     a2, a2          /* if (dividend < 0), return -udividend */
751
.Lpositive:
752
        leaf_return
753
 
754
.Lle_one:
755
        bnez    a3, .Lreturn0
756
 
757
        /* Divide by zero: Use an illegal instruction to force an exception.
758
           The subsequent "DIV0" string can be recognized by the exception
759
           handler to identify the real cause of the exception.  */
760
        ill
761
        .ascii  "DIV0"
762
 
763
.Lreturn0:
764
        movi    a2, 0
765
#endif /* XCHAL_HAVE_DIV32 */
766
        leaf_return
767
        .size   __modsi3, . - __modsi3
768
 
769
#endif /* L_modsi3 */
770
 
771
 
772
#ifdef __XTENSA_EB__
773
#define uh a2
774
#define ul a3
775
#else
776
#define uh a3
777
#define ul a2
778
#endif /* __XTENSA_EB__ */
779
 
780
 
781
#ifdef L_ashldi3
782
        .align  4
783
        .global __ashldi3
784
        .type   __ashldi3, @function
785
__ashldi3:
786
        leaf_entry sp, 16
787
        ssl     a4
788
        bgei    a4, 32, .Llow_only
789
        src     uh, uh, ul
790
        sll     ul, ul
791
        leaf_return
792
 
793
.Llow_only:
794
        sll     uh, ul
795
        movi    ul, 0
796
        leaf_return
797
        .size   __ashldi3, . - __ashldi3
798
 
799
#endif /* L_ashldi3 */
800
 
801
 
802
#ifdef L_ashrdi3
803
        .align  4
804
        .global __ashrdi3
805
        .type   __ashrdi3, @function
806
__ashrdi3:
807
        leaf_entry sp, 16
808
        ssr     a4
809
        bgei    a4, 32, .Lhigh_only
810
        src     ul, uh, ul
811
        sra     uh, uh
812
        leaf_return
813
 
814
.Lhigh_only:
815
        sra     ul, uh
816
        srai    uh, uh, 31
817
        leaf_return
818
        .size   __ashrdi3, . - __ashrdi3
819
 
820
#endif /* L_ashrdi3 */
821
 
822
 
823
#ifdef L_lshrdi3
824
        .align  4
825
        .global __lshrdi3
826
        .type   __lshrdi3, @function
827
__lshrdi3:
828
        leaf_entry sp, 16
829
        ssr     a4
830
        bgei    a4, 32, .Lhigh_only1
831
        src     ul, uh, ul
832
        srl     uh, uh
833
        leaf_return
834
 
835
.Lhigh_only1:
836
        srl     ul, uh
837
        movi    uh, 0
838
        leaf_return
839
        .size   __lshrdi3, . - __lshrdi3
840
 
841
#endif /* L_lshrdi3 */
842
 
843
 
844
#include "ieee754-df.S"
845
#include "ieee754-sf.S"

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