98 lines
3.6 KiB
ArmAsm
98 lines
3.6 KiB
ArmAsm
/*
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Copyright Oliver Kowalke 2009.
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Distributed under the Boost Software License, Version 1.0.
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(See accompanying file LICENSE_1_0.txt or copy at
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http://www.boost.org/LICENSE_1_0.txt)
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*/
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/*******************************************************
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* *
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* ------------------------------------------------- *
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* | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | *
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* ------------------------------------------------- *
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* | 0 | 4 | 8 | 12 | 16 | 20 | 24 | 28 | *
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* ------------------------------------------------- *
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* | F20 | F22 | F24 | F26 | *
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* ------------------------------------------------- *
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* ------------------------------------------------- *
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* | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | *
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* ------------------------------------------------- *
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* | 32 | 36 | 40 | 44 | 48 | 52 | 56 | 60 | *
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* ------------------------------------------------- *
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* | F28 | F30 | S0 | S1 | S2 | S3 | *
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* ------------------------------------------------- *
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* ------------------------------------------------- *
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* | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | *
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* ------------------------------------------------- *
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* | 64 | 68 | 72 | 76 | 80 | 84 | 88 | 92 | *
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* ------------------------------------------------- *
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* | S4 | S5 | S6 | S7 | FP |hiddn| RA | PC | *
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* ------------------------------------------------- *
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* ------------------------------------------------- *
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* | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | *
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* ------------------------------------------------- *
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* | 96 | 100 | 104 | 108 | 112 | 116 | 120 | 124 | *
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* ------------------------------------------------- *
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* | ABI ARGS | GP | FCTX| DATA| | *
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* ------------------------------------------------- *
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* *
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* *****************************************************/
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.file "make_mips32_o32_elf_gas.S"
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.text
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.globl make_fcontext
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.align 2
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.type make_fcontext,@function
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.ent make_fcontext
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make_fcontext:
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#ifdef __PIC__
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.set noreorder
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.cpload $t9
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.set reorder
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#endif
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# shift address in A0 to lower 16 byte boundary
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li $v1, -16 # 0xfffffffffffffff0
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and $v0, $v1, $a0
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# reserve space for context-data on context-stack
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# includes an extra 32 bytes for:
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# - 16-byte incoming argument area required by mips ABI used when
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# jump_context calls the initial function
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# - 4 bytes to save our GP register used in finish
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# - 8 bytes to as space for transfer_t returned to finish
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# - 4 bytes for alignment
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addiu $v0, $v0, -128
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# third arg of make_fcontext() == address of context-function
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sw $a2, 92($v0)
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# save global pointer in context-data
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sw $gp, 112($v0)
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# compute address of returned transfer_t
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addiu $t0, $v0, 116
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sw $t0, 84($v0)
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# compute abs address of label finish
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la $t9, finish
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# save address of finish as return-address for context-function
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# will be entered after context-function returns
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sw $t9, 88($v0)
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jr $ra # return pointer to context-data
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finish:
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# reload our gp register (needed for la)
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lw $gp, 16($sp)
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# call _exit(0)
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# the previous function should have left the 16 bytes incoming argument
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# area on the stack which we reuse for calling _exit
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la $t9, _exit
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move $a0, $zero
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jr $t9
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.end make_fcontext
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.size make_fcontext, .-make_fcontext
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/* Mark that we don't need executable stack. */
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.section .note.GNU-stack,"",%progbits
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