69 lines
1.6 KiB
ArmAsm
69 lines
1.6 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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.globl make_fcontext[DS]
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.globl .make_fcontext[PR]
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.align 2
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.csect .make_fcontext[PR], 3
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.globl _make_fcontext
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#._make_fcontext:
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# save return address into R6
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mflr 6
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# first arg of make_fcontext() == top address of context-function
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# shift address in R3 to lower 16 byte boundary
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clrrwi 3, 3, 4
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# reserve space for context-data on context-stack
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# including 64 byte of linkage + parameter area (R1 % 16 == 0)
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subi 3, 3, 248
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# third arg of make_fcontext() == address of context-function
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stw 5, 176(3)
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# set back-chain to zero
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li 0, 0
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std 0, 184(3)
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# compute address of returned transfer_t
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addi 0, 3, 232
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mr 4, 0
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std 4, 152(3)
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# load LR
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mflr 0
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# jump to label 1
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bl .Label
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.Label:
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# load LR into R4
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mflr 4
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# compute abs address of label .L_finish
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addi 4, 4, .L_finish - .Label
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# restore LR
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mtlr 0
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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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stw 4, 168(3)
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# restore return address from R6
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mtlr 6
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blr # return pointer to context-data
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.L_finish:
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# save return address into R0
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mflr 0
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# save return address on stack, set up stack frame
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stw 0, 8(1)
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# allocate stack space, R1 % 16 == 0
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stwu 1, -32(1)
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# exit code is zero
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li 3, 0
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# exit application
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bl ._exit
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nop
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