| 1 | /* mc68020 __mpn_submul_1 -- Multiply a limb vector with a limb and subtract |
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| 2 | the result from a second limb vector. |
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| 3 | |
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| 4 | Copyright (C) 1992-2024 Free Software Foundation, Inc. |
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| 5 | |
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| 6 | This file is part of the GNU MP Library. |
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| 7 | |
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| 8 | The GNU MP Library is free software; you can redistribute it and/or modify |
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| 9 | it under the terms of the GNU Lesser General Public License as published by |
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| 10 | the Free Software Foundation; either version 2.1 of the License, or (at your |
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| 11 | option) any later version. |
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| 12 | |
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| 13 | The GNU MP Library is distributed in the hope that it will be useful, but |
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| 14 | WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY |
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| 15 | or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public |
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| 16 | License for more details. |
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| 17 | |
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| 18 | You should have received a copy of the GNU Lesser General Public License |
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| 19 | along with the GNU MP Library. If not, see <https://www.gnu.org/licenses/>. */ |
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| 20 | |
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| 21 | /* |
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| 22 | INPUT PARAMETERS |
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| 23 | res_ptr (sp + 4) |
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| 24 | s1_ptr (sp + 8) |
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| 25 | s1_size (sp + 12) |
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| 26 | s2_limb (sp + 16) |
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| 27 | */ |
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| 28 | |
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| 29 | #include "sysdep.h" |
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| 30 | #include "asm-syntax.h" |
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| 31 | |
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| 32 | TEXT |
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| 33 | ENTRY(__mpn_submul_1) |
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| 34 | |
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| 35 | #define res_ptr a0 |
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| 36 | #define s1_ptr a1 |
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| 37 | #define s1_size d2 |
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| 38 | #define s2_limb d4 |
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| 39 | |
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| 40 | /* Save used registers on the stack. */ |
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| 41 | moveml R(d2)-R(d5),MEM_PREDEC(sp) |
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| 42 | cfi_adjust_cfa_offset (4*4) |
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| 43 | cfi_rel_offset (R(d2), 0) |
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| 44 | cfi_rel_offset (R(d3), 4) |
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| 45 | cfi_rel_offset (R(d4), 8) |
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| 46 | cfi_rel_offset (R(d5), 12) |
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| 47 | |
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| 48 | /* Copy the arguments to registers. Better use movem? */ |
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| 49 | movel MEM_DISP(sp,20),R(res_ptr) |
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| 50 | movel MEM_DISP(sp,24),R(s1_ptr) |
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| 51 | movel MEM_DISP(sp,28),R(s1_size) |
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| 52 | movel MEM_DISP(sp,32),R(s2_limb) |
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| 53 | |
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| 54 | eorw #1,R(s1_size) |
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| 55 | clrl R(d1) |
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| 56 | clrl R(d5) |
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| 57 | lsrl #1,R(s1_size) |
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| 58 | bcc L(L1) |
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| 59 | subql #1,R(s1_size) |
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| 60 | subl R(d0),R(d0) /* (d0,cy) <= (0,0) */ |
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| 61 | |
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| 62 | L(Loop:) |
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| 63 | movel MEM_POSTINC(s1_ptr),R(d3) |
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| 64 | mulul R(s2_limb),R(d1):R(d3) |
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| 65 | addxl R(d0),R(d3) |
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| 66 | addxl R(d5),R(d1) |
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| 67 | subl R(d3),MEM_POSTINC(res_ptr) |
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| 68 | L(L1:) movel MEM_POSTINC(s1_ptr),R(d3) |
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| 69 | mulul R(s2_limb),R(d0):R(d3) |
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| 70 | addxl R(d1),R(d3) |
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| 71 | addxl R(d5),R(d0) |
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| 72 | subl R(d3),MEM_POSTINC(res_ptr) |
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| 73 | |
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| 74 | dbf R(s1_size),L(Loop) |
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| 75 | addxl R(d5),R(d0) |
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| 76 | subl #0x10000,R(s1_size) |
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| 77 | bcc L(Loop) |
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| 78 | |
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| 79 | /* Restore used registers from stack frame. */ |
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| 80 | moveml MEM_POSTINC(sp),R(d2)-R(d5) |
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| 81 | cfi_adjust_cfa_offset (-4*4) |
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| 82 | cfi_restore (R(d2)) |
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| 83 | cfi_restore (R(d3)) |
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| 84 | cfi_restore (R(d4)) |
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| 85 | cfi_restore (R(d5)) |
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| 86 | |
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| 87 | rts |
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| 88 | END(__mpn_submul_1) |
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| 89 | |
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