cosmopolitan/libc/runtime/cosmo.S
Jōshin 394d998315
Fix vi modelines (#989)
At least in neovim, `│vi:` is not recognized as a modeline because it
has no preceding whitespace. After fixing this, opening a file yields
an error because `net` is not an option. (`noet`, however, is.)
2023-12-05 14:37:54 -08:00

147 lines
4.8 KiB
ArmAsm

/*-*- mode:unix-assembly; indent-tabs-mode:t; tab-width:8; coding:utf-8 -*-│
vi: set et ft=asm ts=8 tw=8 fenc=utf-8 :vi
Copyright 2020 Justine Alexandra Roberts Tunney
Permission to use, copy, modify, and/or distribute this software for
any purpose with or without fee is hereby granted, provided that the
above copyright notice and this permission notice appear in all copies.
THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL
WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE
AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
PERFORMANCE OF THIS SOFTWARE.
*/
#include "libc/macros.internal.h"
#include "libc/notice.inc"
#include "libc/sysv/consts/prot.h"
#include "libc/sysv/consts/map.h"
#include "libc/intrin/strace.internal.h"
#include "libc/sysv/consts/map.h"
#include "libc/dce.h"
#ifdef __x86_64__
.text.startup
// Cosmopolitan runtime.
//
// @param edi is argc
// @param rsi is argv
// @param rdx is environ
// @param rcx is auxv
// @noreturn
cosmo: push %rbp
mov %rsp,%rbp
mov %edi,%r12d
mov %rsi,%r13
mov %rdx,%r14
mov %rcx,%r15
#if SYSDEBUG
call __strace_init
mov %eax,%r12d
#endif /* SYSDEBUG */
#ifndef NOX87
// Windows always initializes FPU to douuble precision.
// WSL breaks Linux ABI by initializing FPU to double precision.
// This code makes long double long again.
//
// @see System V Application Binary Interface NexGen32e Architecture
// Processor Supplement, Version 1.0, December 5th, 2018
// Section 3.4.1: Initial Stack and Register State
fldcw 1f(%rip)
.rodata
.balign 2
// 8087 FPU Control Word
// IM: Invalid Operation
// DM: Denormal Operand
// ZM: Zero Divide
// OM: Overflow
// UM: Underflow
// PM: Precision
// PC: Precision Control
// {float,,double,long double}
// RC: Rounding Control
// {even, -, +, 0}
//
// drr
1: .short 0b00000000000000000001101111111
.previous
#endif
#ifdef __FAST_MATH__
push %rax
stmxcsr (%rsp)
orl $0x8040,(%rsp)
ldmxcsr (%rsp)
pop %rax
#endif
// run assembly init
call _init
// call constructors
ezlea __init_array_end,ax // static ctors in forward order
.weak __init_array_end // could be called multiple times
ezlea __init_array_start,cx // idempotency recommended
.weak __init_array_start // @see ape/ape.lds
1: cmp %rax,%rcx
je 2f
sub $8,%rax
push %rax
push %rcx
call .Largs
call *(%rax)
pop %rcx
pop %rax
jmp 1b
// call main()
2: call .Largs
.weak main
call main
xchg %eax,%edi
call exit
.Largs: mov %r12d,%edi
mov %r13,%rsi
mov %r14,%rdx
mov %r15,%rcx
ret
.endfn cosmo,weak
// Enables Thread Local Storage.
.init.start 304,_init_tls
push %rdi
push %rsi
call __enable_tls
pop %rsi
pop %rdi
.init.end 304,_init_tls
#if IsAsan()
.init.start 305,_init_symbols
push %rdi
push %rsi
call __init_symbols
pop %rsi
pop %rdi
.init.end 305,_init_symbols
#endif
#ifdef FTRACE
.init.start 306,_init_ftrace
push %rdi
push %rsi
call ftrace_init
mov %eax,%r12d
pop %rsi
pop %rdi
.init.end 306,_init_ftrace
#endif
#endif /* __x86_64__ */