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Diffstat (limited to 'newlib/libc/sys/linux/linuxthreads/machine/i386/sysdep.h')
| -rw-r--r-- | newlib/libc/sys/linux/linuxthreads/machine/i386/sysdep.h | 291 |
1 files changed, 0 insertions, 291 deletions
diff --git a/newlib/libc/sys/linux/linuxthreads/machine/i386/sysdep.h b/newlib/libc/sys/linux/linuxthreads/machine/i386/sysdep.h deleted file mode 100644 index 48aeab195..000000000 --- a/newlib/libc/sys/linux/linuxthreads/machine/i386/sysdep.h +++ /dev/null @@ -1,291 +0,0 @@ -/* Copyright (C) 1992, 93, 95, 96, 97, 98, 99, 00 Free Software Foundation, Inc. - This file is part of the GNU C Library. - Contributed by Ulrich Drepper, <drepper@gnu.org>, August 1995. - - The GNU C Library is free software; you can redistribute it and/or - modify it under the terms of the GNU Lesser General Public - License as published by the Free Software Foundation; either - version 2.1 of the License, or (at your option) any later version. - - The GNU C Library is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - Lesser General Public License for more details. - - You should have received a copy of the GNU Lesser General Public - License along with the GNU C Library; if not, write to the Free - Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA - 02111-1307 USA. */ - -#ifndef _LINUX_I386_SYSDEP_H -#define _LINUX_I386_SYSDEP_H 1 - -#include "i386-sysdep.h" - -/* For Linux we can use the system call table in the header file - /usr/include/asm/unistd.h - of the kernel. But these symbols do not follow the SYS_* syntax - so we have to redefine the `SYS_ify' macro here. */ -#undef SYS_ify -#define SYS_ify(syscall_name) __NR_##syscall_name - -/* ELF-like local names start with `.L'. */ -#undef L -#define L(name) .L##name - -#ifdef __ASSEMBLER__ - -/* Linux uses a negative return value to indicate syscall errors, - unlike most Unices, which use the condition codes' carry flag. - - Since version 2.1 the return value of a system call might be - negative even if the call succeeded. E.g., the `lseek' system call - might return a large offset. Therefore we must not anymore test - for < 0, but test for a real error by making sure the value in %eax - is a real error number. Linus said he will make sure the no syscall - returns a value in -1 .. -4095 as a valid result so we can savely - test with -4095. */ - -/* We don't want the label for the error handle to be global when we define - it here. */ -#ifdef PIC -# define SYSCALL_ERROR_LABEL 0f -#else -# define SYSCALL_ERROR_LABEL syscall_error -#endif - -#undef PSEUDO -#define PSEUDO(name, syscall_name, args) \ - .text; \ - ENTRY (name) \ - DO_CALL (args, syscall_name); \ - cmpl $-4095, %eax; \ - jae SYSCALL_ERROR_LABEL; \ - L(pseudo_end): - -#undef PSEUDO_END -#define PSEUDO_END(name) \ - SYSCALL_ERROR_HANDLER \ - END (name) - -#ifndef PIC -#define SYSCALL_ERROR_HANDLER /* Nothing here; code in sysdep.S is used. */ -#else -/* Store (- %eax) into errno through the GOT. */ -#ifdef _LIBC_REENTRANT -#define SYSCALL_ERROR_HANDLER \ -0:pushl %ebx; \ - call 1f; \ -1:popl %ebx; \ - xorl %edx, %edx; \ - addl $_GLOBAL_OFFSET_TABLE_+[.-1b], %ebx; \ - subl %eax, %edx; \ - pushl %edx; \ - PUSH_ERRNO_LOCATION_RETURN; \ - call BP_SYM (__errno_location)@PLT; \ - POP_ERRNO_LOCATION_RETURN; \ - popl %ecx; \ - popl %ebx; \ - movl %ecx, (%eax); \ - orl $-1, %eax; \ - jmp L(pseudo_end); -/* A quick note: it is assumed that the call to `__errno_location' does - not modify the stack! */ -#else -#define SYSCALL_ERROR_HANDLER \ -0:call 1f; \ -1:popl %ecx; \ - xorl %edx, %edx; \ - addl $_GLOBAL_OFFSET_TABLE_+[.-1b], %ecx; \ - subl %eax, %edx; \ - movl errno@GOT(%ecx), %ecx; \ - movl %edx, (%ecx); \ - orl $-1, %eax; \ - jmp L(pseudo_end); -#endif /* _LIBC_REENTRANT */ -#endif /* PIC */ - -/* Linux takes system call arguments in registers: - - syscall number %eax call-clobbered - arg 1 %ebx call-saved - arg 2 %ecx call-clobbered - arg 3 %edx call-clobbered - arg 4 %esi call-saved - arg 5 %edi call-saved - - The stack layout upon entering the function is: - - 20(%esp) Arg# 5 - 16(%esp) Arg# 4 - 12(%esp) Arg# 3 - 8(%esp) Arg# 2 - 4(%esp) Arg# 1 - (%esp) Return address - - (Of course a function with say 3 arguments does not have entries for - arguments 4 and 5.) - - The following code tries hard to be optimal. A general assumption - (which is true according to the data books I have) is that - - 2 * xchg is more expensive than pushl + movl + popl - - Beside this a neat trick is used. The calling conventions for Linux - tell that among the registers used for parameters %ecx and %edx need - not be saved. Beside this we may clobber this registers even when - they are not used for parameter passing. - - As a result one can see below that we save the content of the %ebx - register in the %edx register when we have less than 3 arguments - (2 * movl is less expensive than pushl + popl). - - Second unlike for the other registers we don't save the content of - %ecx and %edx when we have more than 1 and 2 registers resp. - - The code below might look a bit long but we have to take care for - the pipelined processors (i586). Here the `pushl' and `popl' - instructions are marked as NP (not pairable) but the exception is - two consecutive of these instruction. This gives no penalty on - other processors though. */ - -#undef DO_CALL -#define DO_CALL(args, syscall_name) \ - PUSHARGS_##args \ - DOARGS_##args \ - movl $SYS_ify (syscall_name), %eax; \ - int $0x80 \ - POPARGS_##args - -#define PUSHARGS_0 /* No arguments to push. */ -#define DOARGS_0 /* No arguments to frob. */ -#define POPARGS_0 /* No arguments to pop. */ -#define _PUSHARGS_0 /* No arguments to push. */ -#define _DOARGS_0(n) /* No arguments to frob. */ -#define _POPARGS_0 /* No arguments to pop. */ - -#define PUSHARGS_1 movl %ebx, %edx; PUSHARGS_0 -#define DOARGS_1 _DOARGS_1 (4) -#define POPARGS_1 POPARGS_0; movl %edx, %ebx -#define _PUSHARGS_1 pushl %ebx; _PUSHARGS_0 -#define _DOARGS_1(n) movl n(%esp), %ebx; _DOARGS_0(n-4) -#define _POPARGS_1 _POPARGS_0; popl %ebx - -#define PUSHARGS_2 PUSHARGS_1 -#define DOARGS_2 _DOARGS_2 (8) -#define POPARGS_2 POPARGS_1 -#define _PUSHARGS_2 _PUSHARGS_1 -#define _DOARGS_2(n) movl n(%esp), %ecx; _DOARGS_1 (n-4) -#define _POPARGS_2 _POPARGS_1 - -#define PUSHARGS_3 _PUSHARGS_2 -#define DOARGS_3 _DOARGS_3 (16) -#define POPARGS_3 _POPARGS_3 -#define _PUSHARGS_3 _PUSHARGS_2 -#define _DOARGS_3(n) movl n(%esp), %edx; _DOARGS_2 (n-4) -#define _POPARGS_3 _POPARGS_2 - -#define PUSHARGS_4 _PUSHARGS_4 -#define DOARGS_4 _DOARGS_4 (24) -#define POPARGS_4 _POPARGS_4 -#define _PUSHARGS_4 pushl %esi; _PUSHARGS_3 -#define _DOARGS_4(n) movl n(%esp), %esi; _DOARGS_3 (n-4) -#define _POPARGS_4 _POPARGS_3; popl %esi - -#define PUSHARGS_5 _PUSHARGS_5 -#define DOARGS_5 _DOARGS_5 (32) -#define POPARGS_5 _POPARGS_5 -#define _PUSHARGS_5 pushl %edi; _PUSHARGS_4 -#define _DOARGS_5(n) movl n(%esp), %edi; _DOARGS_4 (n-4) -#define _POPARGS_5 _POPARGS_4; popl %edi - -#else /* !__ASSEMBLER__ */ - -/* We need some help from the assembler to generate optimal code. We - define some macros here which later will be used. */ -asm (".L__X'%ebx = 1\n\t" - ".L__X'%ecx = 2\n\t" - ".L__X'%edx = 2\n\t" - ".L__X'%eax = 3\n\t" - ".L__X'%esi = 3\n\t" - ".L__X'%edi = 3\n\t" - ".L__X'%ebp = 3\n\t" - ".L__X'%esp = 3\n\t" - ".macro bpushl name reg\n\t" - ".if 1 - \\name\n\t" - ".if 2 - \\name\n\t" - "pushl %ebx\n\t" - ".else\n\t" - "xchgl \\reg, %ebx\n\t" - ".endif\n\t" - ".endif\n\t" - ".endm\n\t" - ".macro bpopl name reg\n\t" - ".if 1 - \\name\n\t" - ".if 2 - \\name\n\t" - "popl %ebx\n\t" - ".else\n\t" - "xchgl \\reg, %ebx\n\t" - ".endif\n\t" - ".endif\n\t" - ".endm\n\t" - ".macro bmovl name reg\n\t" - ".if 1 - \\name\n\t" - ".if 2 - \\name\n\t" - "movl \\reg, %ebx\n\t" - ".endif\n\t" - ".endif\n\t" - ".endm\n\t"); - -/* Define a macro which expands inline into the wrapper code for a system - call. */ -#undef INLINE_SYSCALL -#define INLINE_SYSCALL(name, nr, args...) \ - ({ \ - unsigned int resultvar; \ - asm volatile ( \ - LOADARGS_##nr \ - "movl %1, %%eax\n\t" \ - "int $0x80\n\t" \ - RESTOREARGS_##nr \ - : "=a" (resultvar) \ - : "i" (__NR_##name) ASMFMT_##nr(args) : "memory", "cc"); \ - if (resultvar >= 0xfffff001) \ - { \ - __set_errno (-resultvar); \ - resultvar = 0xffffffff; \ - } \ - (int) resultvar; }) - -#define LOADARGS_0 -#define LOADARGS_1 \ - "bpushl .L__X'%k2, %k2\n\t" \ - "bmovl .L__X'%k2, %k2\n\t" -#define LOADARGS_2 LOADARGS_1 -#define LOADARGS_3 LOADARGS_1 -#define LOADARGS_4 LOADARGS_1 -#define LOADARGS_5 LOADARGS_1 - -#define RESTOREARGS_0 -#define RESTOREARGS_1 \ - "bpopl .L__X'%k2, %k2\n\t" -#define RESTOREARGS_2 RESTOREARGS_1 -#define RESTOREARGS_3 RESTOREARGS_1 -#define RESTOREARGS_4 RESTOREARGS_1 -#define RESTOREARGS_5 RESTOREARGS_1 - -#define ASMFMT_0() -#define ASMFMT_1(arg1) \ - , "acdSD" (arg1) -#define ASMFMT_2(arg1, arg2) \ - , "adCD" (arg1), "c" (arg2) -#define ASMFMT_3(arg1, arg2, arg3) \ - , "aCD" (arg1), "c" (arg2), "d" (arg3) -#define ASMFMT_4(arg1, arg2, arg3, arg4) \ - , "aD" (arg1), "c" (arg2), "d" (arg3), "S" (arg4) -#define ASMFMT_5(arg1, arg2, arg3, arg4, arg5) \ - , "a" (arg1), "c" (arg2), "d" (arg3), "S" (arg4), "D" (arg5) - -#endif /* __ASSEMBLER__ */ - -#endif /* linux/i386/sysdep.h */ |