projects / thirdparty / glibc.git / blame
| Commit | Line | Data |
|---|---|---|
| 9a0a462c | 1 | /* Shift a limb left, low level routine. |
| 2b778ceb | 2 | Copyright (C) 1996-2021 Free Software Foundation, Inc. |
| 9a0a462c UD |
3 | This file is part of the GNU C Library. |
| 4 | ||
| 5 | The GNU C Library is free software; you can redistribute it and/or | |
| 41bdb6e2 AJ |
6 | modify it under the terms of the GNU Lesser General Public |
| 7 | License as published by the Free Software Foundation; either | |
| 8 | version 2.1 of the License, or (at your option) any later version. | |
| 9a0a462c UD |
9 | |
| 10 | The GNU C Library is distributed in the hope that it will be useful, | |
| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| 41bdb6e2 | 13 | Lesser General Public License for more details. |
| 9a0a462c | 14 | |
| 41bdb6e2 | 15 | You should have received a copy of the GNU Lesser General Public |
| 59ba27a6 | 16 | License along with the GNU C Library; if not, see |
| 5a82c748 | 17 | <https://www.gnu.org/licenses/>. */ |
| 9a0a462c UD |
18 | |
| 19 | #include <sysdep.h> | |
| 20 | ||
| 21 | /* mp_limb_t mpn_lshift (mp_ptr wp, mp_srcptr up, mp_size_t usize, | |
| 350635a5 | 22 | unsigned int cnt) */ |
| 9a0a462c | 23 | |
| b5510883 | 24 | EALIGN (__mpn_lshift, 3, 0) |
| fa87f403 | 25 | |
| 217eb19b UD |
26 | mtctr r5 # copy size into CTR |
| 27 | cmplwi cr0,r5,16 # is size < 16 | |
| 28 | slwi r0,r5,2 | |
| 29 | add r7,r3,r0 # make r7 point at end of res | |
| 30 | add r4,r4,r0 # make r4 point at end of s1 | |
| 31 | lwzu r11,-4(r4) # load first s1 limb | |
| 32 | subfic r8,r6,32 | |
| 33 | srw r3,r11,r8 # compute function return value | |
| 34 | bge cr0,L(big) # branch if size >= 16 | |
| 9a0a462c UD |
35 | |
| 36 | bdz L(end1) | |
| 37 | ||
| 4e141d64 | 38 | L(0): lwzu r10,-4(r4) |
| 217eb19b UD |
39 | slw r9,r11,r6 |
| 40 | srw r12,r10,r8 | |
| 41 | or r9,r9,r12 | |
| 42 | stwu r9,-4(r7) | |
| 9a0a462c | 43 | bdz L(end2) |
| 217eb19b UD |
44 | lwzu r11,-4(r4) |
| 45 | slw r9,r10,r6 | |
| 46 | srw r12,r11,r8 | |
| 47 | or r9,r9,r12 | |
| 48 | stwu r9,-4(r7) | |
| 4e141d64 | 49 | bdnz L(0) |
| 9a0a462c | 50 | |
| 217eb19b UD |
51 | L(end1):slw r0,r11,r6 |
| 52 | stw r0,-4(r7) | |
| 9a0a462c UD |
53 | blr |
| 54 | ||
| 55 | ||
| 56 | /* Guaranteed not to succeed. */ | |
| 217eb19b | 57 | L(boom): tweq r0,r0 |
| 9a0a462c UD |
58 | |
| 59 | /* We imitate a case statement, by using (yuk!) fixed-length code chunks, | |
| 60 | of size 4*12 bytes. We have to do this (or something) to make this PIC. */ | |
| 217eb19b | 61 | L(big): mflr r9 |
| a7e91561 | 62 | cfi_register(lr,r9) |
| 217eb19b UD |
63 | bltl- cr0,L(boom) # Never taken, only used to set LR. |
| 64 | slwi r10,r6,4 | |
| 65 | mflr r12 | |
| 66 | add r10,r12,r10 | |
| 67 | slwi r8,r6,5 | |
| 68 | add r10,r8,r10 | |
| 69 | mtctr r10 | |
| 70 | addi r5,r5,-1 | |
| a7e91561 UD |
71 | mtlr r9 |
| 72 | cfi_same_value (lr) | |
| 9a0a462c UD |
73 | bctr |
| 74 | ||
| 217eb19b UD |
75 | L(end2):slw r0,r10,r6 |
| 76 | stw r0,-4(r7) | |
| 9a0a462c UD |
77 | blr |
| 78 | ||
| 79 | #define DO_LSHIFT(n) \ | |
| 217eb19b | 80 | mtctr r5; \ |
| 4e141d64 | 81 | L(n): lwzu r10,-4(r4); \ |
| 217eb19b UD |
82 | slwi r9,r11,n; \ |
| 83 | inslwi r9,r10,n,32-n; \ | |
| 84 | stwu r9,-4(r7); \ | |
| 9a0a462c | 85 | bdz- L(end2); \ |
| 217eb19b UD |
86 | lwzu r11,-4(r4); \ |
| 87 | slwi r9,r10,n; \ | |
| 88 | inslwi r9,r11,n,32-n; \ | |
| 89 | stwu r9,-4(r7); \ | |
| 4e141d64 | 90 | bdnz L(n); \ |
| 9a0a462c UD |
91 | b L(end1) |
| 92 | ||
| 93 | DO_LSHIFT(1) | |
| 94 | DO_LSHIFT(2) | |
| 95 | DO_LSHIFT(3) | |
| 96 | DO_LSHIFT(4) | |
| 97 | DO_LSHIFT(5) | |
| 98 | DO_LSHIFT(6) | |
| 99 | DO_LSHIFT(7) | |
| 100 | DO_LSHIFT(8) | |
| 101 | DO_LSHIFT(9) | |
| 102 | DO_LSHIFT(10) | |
| 103 | DO_LSHIFT(11) | |
| 104 | DO_LSHIFT(12) | |
| 105 | DO_LSHIFT(13) | |
| 106 | DO_LSHIFT(14) | |
| 107 | DO_LSHIFT(15) | |
| 108 | DO_LSHIFT(16) | |
| 109 | DO_LSHIFT(17) | |
| 110 | DO_LSHIFT(18) | |
| 111 | DO_LSHIFT(19) | |
| 112 | DO_LSHIFT(20) | |
| 113 | DO_LSHIFT(21) | |
| 114 | DO_LSHIFT(22) | |
| 115 | DO_LSHIFT(23) | |
| 116 | DO_LSHIFT(24) | |
| 117 | DO_LSHIFT(25) | |
| 118 | DO_LSHIFT(26) | |
| 119 | DO_LSHIFT(27) | |
| 120 | DO_LSHIFT(28) | |
| 121 | DO_LSHIFT(29) | |
| 122 | DO_LSHIFT(30) | |
| 123 | DO_LSHIFT(31) | |
| 124 | ||
| b5510883 | 125 | END (__mpn_lshift) |