projects / thirdparty / glibc.git / blame
| Commit | Line | Data |
|---|---|---|
| 3de9f02e RM |
1 | /* mc68020 __mpn_lshift -- Shift left a low-level natural-number integer. |
| 2 | ||
| 56d7f029 | 3 | Copyright (C) 1996, 1998 Free Software Foundation, Inc. |
| 3de9f02e RM |
4 | |
| 5 | This file is part of the GNU MP Library. | |
| 6 | ||
| 7 | The GNU MP Library is free software; you can redistribute it and/or modify | |
| 8 | it under the terms of the GNU Library General Public License as published by | |
| 9 | the Free Software Foundation; either version 2 of the License, or (at your | |
| 10 | option) any later version. | |
| 11 | ||
| 12 | The GNU MP Library is distributed in the hope that it will be useful, but | |
| 13 | WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY | |
| 14 | or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public | |
| 15 | License for more details. | |
| 16 | ||
| 17 | You should have received a copy of the GNU Library General Public License | |
| 18 | along with the GNU MP Library; see the file COPYING.LIB. If not, write to | |
| 6c07070b RM |
19 | the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, |
| 20 | MA 02111-1307, USA. */ | |
| 3de9f02e RM |
21 | |
| 22 | /* | |
| 23 | INPUT PARAMETERS | |
| 24 | res_ptr (sp + 4) | |
| 25 | s_ptr (sp + 8) | |
| 26 | s_size (sp + 16) | |
| 27 | cnt (sp + 12) | |
| 28 | */ | |
| 29 | ||
| 30 | #include "sysdep.h" | |
| 31 | #include "asm-syntax.h" | |
| 32 | ||
| 33 | #define res_ptr a1 | |
| 34 | #define s_ptr a0 | |
| 35 | #define s_size d6 | |
| 36 | #define cnt d4 | |
| 37 | ||
| 38 | TEXT | |
| 56d7f029 | 39 | ENTRY(__mpn_lshift) |
| 3de9f02e RM |
40 | |
| 41 | /* Save used registers on the stack. */ | |
| 42 | moveml R(d2)-R(d6)/R(a2),MEM_PREDEC(sp) | |
| 43 | ||
| 44 | /* Copy the arguments to registers. */ | |
| 45 | movel MEM_DISP(sp,28),R(res_ptr) | |
| 46 | movel MEM_DISP(sp,32),R(s_ptr) | |
| 47 | movel MEM_DISP(sp,36),R(s_size) | |
| 48 | movel MEM_DISP(sp,40),R(cnt) | |
| 49 | ||
| 50 | moveql #1,R(d5) | |
| 51 | cmpl R(d5),R(cnt) | |
| 52 | bne L(Lnormal) | |
| 53 | cmpl R(s_ptr),R(res_ptr) | |
| 54 | bls L(Lspecial) /* jump if s_ptr >= res_ptr */ | |
| 55 | #if (defined (__mc68020__) || defined (__NeXT__) || defined(mc68020)) | |
| 56 | lea MEM_INDX1(s_ptr,s_size,l,4),R(a2) | |
| 57 | #else /* not mc68020 */ | |
| 58 | movel R(s_size),R(d0) | |
| 59 | asll #2,R(d0) | |
| 60 | lea MEM_INDX(s_ptr,d0,l),R(a2) | |
| 61 | #endif | |
| 62 | cmpl R(res_ptr),R(a2) | |
| 63 | bls L(Lspecial) /* jump if res_ptr >= s_ptr + s_size */ | |
| 64 | ||
| 65 | L(Lnormal:) | |
| 66 | moveql #32,R(d5) | |
| 67 | subl R(cnt),R(d5) | |
| 68 | ||
| 69 | #if (defined (__mc68020__) || defined (__NeXT__) || defined(mc68020)) | |
| 70 | lea MEM_INDX1(s_ptr,s_size,l,4),R(s_ptr) | |
| 71 | lea MEM_INDX1(res_ptr,s_size,l,4),R(res_ptr) | |
| 72 | #else /* not mc68000 */ | |
| 73 | movel R(s_size),R(d0) | |
| 74 | asll #2,R(d0) | |
| 75 | addl R(s_size),R(s_ptr) | |
| 76 | addl R(s_size),R(res_ptr) | |
| 77 | #endif | |
| 78 | movel MEM_PREDEC(s_ptr),R(d2) | |
| 79 | movel R(d2),R(d0) | |
| 80 | lsrl R(d5),R(d0) /* compute carry limb */ | |
| 81 | ||
| 82 | lsll R(cnt),R(d2) | |
| 83 | movel R(d2),R(d1) | |
| 84 | subql #1,R(s_size) | |
| 85 | beq L(Lend) | |
| 86 | lsrl #1,R(s_size) | |
| 87 | bcs L(L1) | |
| 88 | subql #1,R(s_size) | |
| 89 | ||
| 90 | L(Loop:) | |
| 91 | movel MEM_PREDEC(s_ptr),R(d2) | |
| 92 | movel R(d2),R(d3) | |
| 93 | lsrl R(d5),R(d3) | |
| 94 | orl R(d3),R(d1) | |
| 95 | movel R(d1),MEM_PREDEC(res_ptr) | |
| 96 | lsll R(cnt),R(d2) | |
| 97 | L(L1:) | |
| 98 | movel MEM_PREDEC(s_ptr),R(d1) | |
| 99 | movel R(d1),R(d3) | |
| 100 | lsrl R(d5),R(d3) | |
| 101 | orl R(d3),R(d2) | |
| 102 | movel R(d2),MEM_PREDEC(res_ptr) | |
| 103 | lsll R(cnt),R(d1) | |
| 104 | ||
| 105 | dbf R(s_size),L(Loop) | |
| 106 | subl #0x10000,R(s_size) | |
| 107 | bcc L(Loop) | |
| 108 | ||
| 109 | L(Lend:) | |
| 110 | movel R(d1),MEM_PREDEC(res_ptr) /* store least significant limb */ | |
| 111 | ||
| 112 | /* Restore used registers from stack frame. */ | |
| 113 | moveml MEM_POSTINC(sp),R(d2)-R(d6)/R(a2) | |
| 114 | rts | |
| 115 | ||
| 116 | /* We loop from least significant end of the arrays, which is only | |
| 910e2e14 | 117 | permissible if the source and destination don't overlap, since the |
| 3de9f02e RM |
118 | function is documented to work for overlapping source and destination. */ |
| 119 | ||
| 120 | L(Lspecial:) | |
| 121 | clrl R(d0) /* initialize carry */ | |
| 122 | eorw #1,R(s_size) | |
| 123 | lsrl #1,R(s_size) | |
| 124 | bcc L(LL1) | |
| 125 | subql #1,R(s_size) | |
| 126 | ||
| 127 | L(LLoop:) | |
| 128 | movel MEM_POSTINC(s_ptr),R(d2) | |
| 129 | addxl R(d2),R(d2) | |
| 130 | movel R(d2),MEM_POSTINC(res_ptr) | |
| 131 | L(LL1:) | |
| 132 | movel MEM_POSTINC(s_ptr),R(d2) | |
| 133 | addxl R(d2),R(d2) | |
| 134 | movel R(d2),MEM_POSTINC(res_ptr) | |
| 135 | ||
| 136 | dbf R(s_size),L(LLoop) | |
| 137 | addxl R(d0),R(d0) /* save cy in lsb */ | |
| 138 | subl #0x10000,R(s_size) | |
| 139 | bcs L(LLend) | |
| 140 | lsrl #1,R(d0) /* restore cy */ | |
| 141 | bra L(LLoop) | |
| 142 | ||
| 143 | L(LLend:) | |
| 144 | /* Restore used registers from stack frame. */ | |
| 145 | moveml MEM_POSTINC(sp),R(d2)-R(d6)/R(a2) | |
| 146 | rts | |
| 56d7f029 | 147 | END(__mpn_lshift) |