|
|
; Copyright Edward Nevill + Oliver Kowalke 2015; Distributed under the Boost Software License, Version 1.0.; (See accompanying file LICENSE_1_0.txt or copy at; http://www.boost.org/LICENSE_1_0.txt)
;*******************************************************;* *;* ------------------------------------------------- *;* | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | *;* ------------------------------------------------- *;* | 0x0 | 0x4 | 0x8 | 0xc | 0x10| 0x14| 0x18| 0x1c| *;* ------------------------------------------------- *;* | d8 | d9 | d10 | d11 | *;* ------------------------------------------------- *;* ------------------------------------------------- *;* | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | *;* ------------------------------------------------- *;* | 0x20| 0x24| 0x28| 0x2c| 0x30| 0x34| 0x38| 0x3c| *;* ------------------------------------------------- *;* | d12 | d13 | d14 | d15 | *;* ------------------------------------------------- *;* ------------------------------------------------- *;* | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | *;* ------------------------------------------------- *;* | 0x40| 0x44| 0x48| 0x4c| 0x50| 0x54| 0x58| 0x5c| *;* ------------------------------------------------- *;* | x19 | x20 | x21 | x22 | *;* ------------------------------------------------- *;* ------------------------------------------------- *;* | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | *;* ------------------------------------------------- *;* | 0x60| 0x64| 0x68| 0x6c| 0x70| 0x74| 0x78| 0x7c| *;* ------------------------------------------------- *;* | x23 | x24 | x25 | x26 | *;* ------------------------------------------------- *;* ------------------------------------------------- *;* | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39 | *;* ------------------------------------------------- *;* | 0x80| 0x84| 0x88| 0x8c| 0x90| 0x94| 0x98| 0x9c| *;* ------------------------------------------------- *;* | x27 | x28 | FP (x29) | LR (x30) | *;* ------------------------------------------------- *;* ------------------------------------------------- *;* | 40 | 41 | 42 | 43 | 44 | 45 | 46 | 47 | *;* ------------------------------------------------- *;* | 0xa0| 0xa4| 0xa8| 0xac| 0xb0| 0xb4| 0xb8| 0xbc| *;* ------------------------------------------------- *;* | base | limit | dealloc | fiber data| *;* ------------------------------------------------- *;* ------------------------------------------------- *;* | 48 | 49 | 50 | 51 | | | *;* ------------------------------------------------- *;* | 0xc0| 0xc4| 0xc8| 0xcc| | | *;* ------------------------------------------------- *;* | PC | align | | | *;* ------------------------------------------------- *;* *;*******************************************************
AREA |.text|, CODE, READONLY, ALIGN=4, CODEALIGN EXPORT make_fcontext IMPORT _exit
make_fcontext proc ; save stack top address to x3 mov x3, x0
; shift address in x0 (allocated stack) to lower 16 byte boundary and x0, x0, ~0xF
; reserve space for context-data on context-stack sub x0, x0, #0xd0
; save top address of context_stack as 'base' str x3, [x0, #0xa0] ; save bottom address of context-stack as 'limit' and 'dealloction stack' sub x3, x3, x1 stp x3, x3, [x0, #0xa8] ; save 0 as 'fiber data' str xzr, [x0, #0xb8]
; third arg of make_fcontext() == address of context-function ; store address as x19 for trampoline str x2, [x0, #0x40] ; store trampoline address as pc adr x2, trampoline str x2, [x0, #0xc0]
; save address of finish as return-address for context-function ; will be entered after context-function returns (LR register) adr x1, finish str x1, [x0, #0x98]
ret x30 ; return pointer to context-data (x0)
trampoline stp fp, lr, [sp, #-0x10]! mov fp, sp blr x19
finish ; exit code is zero mov x0, #0 ; exit application bl _exit ENDP END
|
