This prepares for an incompatible compiler toolchain change scheduled for Sortix 0.10 development where crt0.o is used instead of crt1.o.
58 lines
1.7 KiB
ArmAsm
58 lines
1.7 KiB
ArmAsm
/*******************************************************************************
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Copyright(C) Jonas 'Sortie' Termansen 2011, 2012.
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This file is part of the Sortix C Library.
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The Sortix C Library is free software: you can redistribute it and/or modify
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it under the terms of the GNU Lesser General Public License as published by
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the Free Software Foundation, either version 3 of the License, or (at your
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option) any later version.
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The Sortix C Library is distributed in the hope that it will be useful, but
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WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
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or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
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License for more details.
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You should have received a copy of the GNU Lesser General Public License
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along with the Sortix C Library. If not, see <http://www.gnu.org/licenses/>.
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x64/crt0.S
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Implement the _start symbol at which execution begins which performs the
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task of initializing the standard library and executing the main function.
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*******************************************************************************/
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.section .text
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.global _start
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.type _start, @function
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_start:
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# Set up end of the stack frame linked list.
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xorl %ebp, %ebp
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pushq %rbp # rip=0
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pushq %rbp # rbp=0
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movq %rsp, %rbp
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movq %rcx, environ # envp
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# Prepare signals, memory allocation, stdio and such.
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pushq %rsi
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pushq %rdi
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pushq %rcx
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call initialize_standard_library
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# Run the global constructors.
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call _init
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# Run main
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popq %rdx # Note! envp is now %rdx (previously %rcx)
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popq %rdi
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popq %rsi
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call main
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# Terminate the process with main's exit code.
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movl %eax, %edi
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call exit
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.size _start, .-_start
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