libostd/src/asm/arm64/make_arm64_aapcs_elf_gas.S

86 lines
3.7 KiB
ArmAsm

/*
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 | LR | *
* ------------------------------------------------- *
* ------------------------------------------------- *
* | 40 | 41 | 42 | 43 | | | *
* ------------------------------------------------- *
* | 0xa0| 0xa4| 0xa8| 0xac| | | *
* ------------------------------------------------- *
* | PC | align | | | *
* ------------------------------------------------- *
* *
*******************************************************/
.file "make_arm64_aapcs_elf_gas.S"
.text
.align 2
.global ostd_make_fcontext
.type ostd_make_fcontext, %function
ostd_make_fcontext:
# 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, #0xb0
# third arg of ostd_make_fcontext() == address of context-function
# store address as a PC to jump in
str x2, [x0, #0xa0]
# 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)
finish:
# exit code is zero
mov x0, #0
# exit application
bl _exit
.size ostd_make_fcontext,.-ostd_make_fcontext
# Mark that we don't need executable stack.
.section .note.GNU-stack,"",%progbits