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/*
Copyright Oliver Kowalke 2009.
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 | *
* ------------------------------------------------- *
* | 0 | 4 | 8 | 12 | 16 | 20 | 24 | 28 | *
* ------------------------------------------------- *
* | F20 | F22 | F24 | F26 | *
* ------------------------------------------------- *
* ------------------------------------------------- *
* | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | *
* ------------------------------------------------- *
* | 32 | 36 | 40 | 44 | 48 | 52 | 56 | 60 | *
* ------------------------------------------------- *
* | F28 | F30 | S0 | S1 | S2 | S3 | *
* ------------------------------------------------- *
* ------------------------------------------------- *
* | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | *
* ------------------------------------------------- *
* | 64 | 68 | 72 | 76 | 80 | 84 | 88 | 92 | *
* ------------------------------------------------- *
* | S4 | S5 | S6 | S7 | FP |hiddn| RA | PC | *
* ------------------------------------------------- *
* ------------------------------------------------- *
* | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | *
* ------------------------------------------------- *
* | 96 | 100 | 104 | 108 | 112 | 116 | 120 | 124 | *
* ------------------------------------------------- *
* | ABI ARGS | GP | FCTX| DATA| | *
* ------------------------------------------------- *
* *
* *****************************************************/
.file "make_mips32_o32_elf_gas.S"
.text
.globl make_fcontext
.align 2
.type make_fcontext,@function
.ent make_fcontext
make_fcontext:
#ifdef __PIC__
.set noreorder
.cpload $t9
.set reorder
#endif
# shift address in A0 to lower 16 byte boundary
li $v1, -16 # 0xfffffffffffffff0
and $v0, $v1, $a0
# reserve space for context-data on context-stack
# includes an extra 32 bytes for:
# - 16-byte incoming argument area required by mips ABI used when
# jump_context calls the initial function
# - 4 bytes to save our GP register used in finish
# - 8 bytes to as space for transfer_t returned to finish
# - 4 bytes for alignment
addiu $v0, $v0, -128
# third arg of make_fcontext() == address of context-function
sw $a2, 92($v0)
# save global pointer in context-data
sw $gp, 112($v0)
# compute address of returned transfer_t
addiu $t0, $v0, 116
sw $t0, 84($v0)
# compute abs address of label finish
la $t9, finish
# save address of finish as return-address for context-function
# will be entered after context-function returns
sw $t9, 88($v0)
jr $ra # return pointer to context-data
finish:
# reload our gp register (needed for la)
lw $gp, 16($sp)
# call _exit(0)
# the previous function should have left the 16 bytes incoming argument
# area on the stack which we reuse for calling _exit
la $t9, _exit
move $a0, $zero
jr $t9
.end make_fcontext
.size make_fcontext, .-make_fcontext
/* Mark that we don't need executable stack. */
.section .note.GNU-stack,"",%progbits
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