| 1 | /* Swap to new context. |
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| 2 | Copyright (C) 2008-2024 Free Software Foundation, Inc. |
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| 3 | This file is part of the GNU C Library. |
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| 4 | |
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| 5 | The GNU C Library is free software; you can redistribute it and/or |
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| 6 | modify it under the terms of the GNU Lesser General Public |
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| 7 | License as published by the Free Software Foundation; either |
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| 8 | version 2.1 of the License, or (at your option) any later version. |
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| 9 | |
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| 10 | The GNU C Library is distributed in the hope that it will be useful, |
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| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
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| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
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| 13 | Lesser General Public License for more details. |
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| 14 | |
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| 15 | You should have received a copy of the GNU Lesser General Public |
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| 16 | License along with the GNU C Library. If not, see |
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| 17 | <https://www.gnu.org/licenses/>. */ |
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| 18 | |
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| 19 | #include <sysdep.h> |
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| 20 | #include "ucontext_i.h" |
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| 21 | |
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| 22 | .text |
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| 23 | ENTRY(__swapcontext) |
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| 24 | |
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| 25 | /* Copy rp to ret0 (r28). */ |
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| 26 | copy %rp,%ret0 |
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| 27 | |
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| 28 | /* Create a frame. */ |
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| 29 | ldo 64(%sp),%sp |
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| 30 | .cfi_def_cfa_offset -64 |
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| 31 | |
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| 32 | /* Save the current machine context to oucp. */ |
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| 33 | bl __getcontext,%rp |
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| 34 | |
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| 35 | /* Copy oucp to register ret1 (r29). __getcontext saves and |
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| 36 | restores it on a normal return. It is restored from oR29 |
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| 37 | on reactivation. */ |
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| 38 | copy %r26,%ret1 |
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| 39 | |
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| 40 | /* Pop frame. */ |
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| 41 | ldo -64(%sp),%sp |
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| 42 | .cfi_def_cfa_offset 0 |
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| 43 | |
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| 44 | /* Load return pointer from oR28. */ |
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| 45 | ldw oR28(%ret1),%rp |
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| 46 | |
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| 47 | /* Return if error. */ |
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| 48 | or,= %r0,%ret0,%r0 |
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| 49 | bv,n %r0(%rp) |
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| 50 | |
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| 51 | /* Load sc_sar flag. */ |
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| 52 | ldb oSAR(%ret1),%r20 |
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| 53 | |
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| 54 | /* Return if oucp context has been reactivated. */ |
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| 55 | or,= %r0,%r20,%r0 |
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| 56 | bv,n %r0(%rp) |
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| 57 | |
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| 58 | /* Mark sc_sar flag. */ |
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| 59 | ldi 1,%r20 |
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| 60 | stb %r20,oSAR(%ret1) |
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| 61 | |
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| 62 | /* Activate the machine context in ucp. */ |
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| 63 | bl __setcontext,%rp |
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| 64 | ldw oR25(%ret1),%r26 |
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| 65 | |
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| 66 | /* Load return pointer. */ |
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| 67 | ldw oR28(%ret1),%rp |
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| 68 | bv,n %r0(%rp) |
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| 69 | |
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| 70 | END(__swapcontext) |
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| 71 | |
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| 72 | weak_alias (__swapcontext, swapcontext) |
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| 73 | |
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