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Diffstat (limited to 'ports/sysdeps/unix/sysv/linux/am33/sysdep.h')
| -rw-r--r-- | ports/sysdeps/unix/sysv/linux/am33/sysdep.h | 316 |
1 files changed, 316 insertions, 0 deletions
diff --git a/ports/sysdeps/unix/sysv/linux/am33/sysdep.h b/ports/sysdeps/unix/sysv/linux/am33/sysdep.h new file mode 100644 index 0000000000..68f93f8003 --- /dev/null +++ b/ports/sysdeps/unix/sysv/linux/am33/sysdep.h @@ -0,0 +1,316 @@ +/* Copyright 2001, 2004 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Alexandre Oliva <aoliva@redhat.com>. + Based on ../i386/sysdep.h. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Library General Public License as + published by the Free Software Foundation; either version 2 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 + Library General Public License for more details. + + You should have received a copy of the GNU Library General Public + License along with the GNU C Library. If not, see + <http://www.gnu.org/licenses/>. */ + +#ifndef _LINUX_AM33_SYSDEP_H +#define _LINUX_AM33_SYSDEP_H 1 + +/* There is some commonality. */ +#include "../../../am33/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 (syscall_name, args); \ + cmp -126,d0; \ + bls L(pseudo_end); \ + jmp SYSCALL_ERROR_LABEL; \ + L(pseudo_end): \ + mov d0,a0; + +#undef PSEUDO_END +#define PSEUDO_END(name) \ + SYSCALL_ERROR_HANDLER \ + END (name) + +#undef PSEUDO_NOERROR +#define PSEUDO_NOERRNO(name, syscall_name, args) \ + .text; \ + ENTRY (name) \ + DO_CALL (syscall_name, args) + +#undef PSEUDO_END_NOERRNO +#define PSEUDO_END_NOERRNO(name) \ + END (name) + +#define ret_NOERRNO ret + +/* The function has to return the error code. */ +#undef PSEUDO_ERRVAL +#define PSEUDO_ERRVAL(name, syscall_name, args) \ + .text; \ + ENTRY (name) \ + DO_CALL (syscall_name, args); \ + clr d1; \ + sub d0,d1,d0 + +#undef PSEUDO_END_ERRVAL +#define PSEUDO_END_ERRVAL(name) \ + END (name) + +#define ret_ERRVAL ret + +#ifndef PIC +#define SYSCALL_ERROR_HANDLER /* Nothing here; code in sysdep.S is used. */ +#else +/* Store (- d0) into errno through the GOT. */ +#ifdef _LIBC_REENTRANT +#define SYSCALL_ERROR_HANDLER \ +0:movm [d2,a2],(sp); \ + add -12,sp; \ +1:mov pc,a2; \ + add _GLOBAL_OFFSET_TABLE_-(1b-.),a2; \ + clr d2; \ + sub d0,d2; \ + call __errno_location@PLT,[],0; \ + mov d2,(a0); \ + add 12,sp; \ + movm (sp),[d2,a2]; \ + mov -1,d0; \ + mov d0,a0; \ + 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:mov pc,a0; \ + add _GLOBAL_OFFSET_TABLE_-(0b-.),a0; \ + clr d1; \ + sub d0,d1; \ + mov (errno@GOT,a0),a1; \ + mov d1,(a0); \ + mov -1,d0; \ + mov d0,a0; \ + jmp L(pseudo_end); +#endif /* _LIBC_REENTRANT */ +#endif /* PIC */ + +/* Linux takes system call arguments in registers: + + syscall number d0 call-clobbered + arg 1 a0 call-clobbered + arg 2 d1 call-clobbered + arg 3 a3 call-saved + arg 4 a2 call-saved + arg 5 d3 call-saved + arg 6 d2 call-saved + + The stack layout upon entering the function is: + + (24,sp) Arg# 6 + (20,sp) Arg# 5 + (16,sp) Arg# 4 + (12,sp) Arg# 3 + d1 Arg# 2 + d0 Arg# 1 + (sp) Return address + + (Of course a function with say 3 arguments does not have entries for + arguments 4, 5 and 6.) */ + +#undef DO_CALL +#define DO_CALL(syscall_name, args) \ + PUSHARGS_##args \ + DOARGS_##args \ + mov SYS_ify (syscall_name),d0; \ + syscall 0 \ + POPARGS_##args + +#define PUSHARGS_0 /* No arguments to push. */ +#define _DOARGS_0(N) /* No arguments to frob. */ +#define DOARGS_0 /* No arguments to frob. */ +#define POPARGS_0 /* No arguments to pop. */ + +#define PUSHARGS_1 /* No arguments to push. */ +#define _DOARGS_1(N) _DOARGS_0 (N-4) mov d0,a0; +#define DOARGS_1 _DOARGS_1 (4) +#define POPARGS_1 /* No arguments to pop. */ + +#define PUSHARGS_2 /* No arguments to push. */ +#define _DOARGS_2(N) _DOARGS_1 (N-4) /* Argument already in d1. */ +#define DOARGS_2 _DOARGS_2 (8) +#define POPARGS_2 /* No arguments to pop. */ + +#define PUSHARGS_3 movm [a3],(sp); +#define _DOARGS_3(N) _DOARGS_2 (N-4) mov (N,sp),a3; +#define DOARGS_3 _DOARGS_3 (16) +#define POPARGS_3 ; movm (sp),[a3] + +#define PUSHARGS_4 movm [a2,a3],(sp); +#define _DOARGS_4(N) _DOARGS_3 (N-4) mov (N,sp),a2; +#define DOARGS_4 _DOARGS_4 (24) +#define POPARGS_4 ; movm (sp),[a2,a3] + +#define PUSHARGS_5 movm [d3,a2,a3],(sp); +#define _DOARGS_5(N) _DOARGS_4 (N-4) mov (N,sp),d3; +#define DOARGS_5 _DOARGS_5 (32) +#define POPARGS_5 ; movm (sp),[d3,a2,a3] + +#define PUSHARGS_6 movm [d2,d3,a2,a3],(sp); +#define _DOARGS_6(N) _DOARGS_5 (N-4) mov (N,sp),d2; +#define DOARGS_6 _DOARGS_6 (40) +#define POPARGS_6 ; movm (sp),[d2,d3,a2,a3] + +#else /* !__ASSEMBLER__ */ + +/* 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 = INTERNAL_SYSCALL (name, , nr, args); \ + if (__builtin_expect (INTERNAL_SYSCALL_ERROR_P (resultvar, ), 0)) \ + { \ + __set_errno (INTERNAL_SYSCALL_ERRNO (resultvar, )); \ + resultvar = 0xffffffff; \ + } \ + (int) resultvar; }) + +#define INTERNAL_SYSCALL(name, err, nr, args...) \ +({ \ + register long __sc0 asm ("d0") = __NR_##name; \ + inline_syscall##nr(name, ## args); \ + __sc0; \ +}) + +#undef INTERNAL_SYSCALL_DECL +#define INTERNAL_SYSCALL_DECL(err) do { } while (0) + +#undef INTERNAL_SYSCALL_ERROR_P +#define INTERNAL_SYSCALL_ERROR_P(val, err) \ + ((unsigned int) (val) >= (unsigned long)-125) + +#undef INTERNAL_SYSCALL_ERRNO +#define INTERNAL_SYSCALL_ERRNO(val, err) (-(val)) + +#define inline_syscall0(name,dummy...) \ +__asm__ __volatile__ ("syscall 0" \ + : "+d" (__sc0) \ + : : "memory") + +#define inline_syscall1(name,arg1) \ +register long __sc1 asm ("a0") = (long) (arg1); \ +inline_syscall0 (name); \ +__asm__ __volatile__ ("" : : "r" (__sc1)) + +#define inline_syscall2(name,arg1,arg2) \ +register long __sc2 asm ("d1") = (long) (arg2); \ +inline_syscall1 (name,(arg1)); \ +__asm__ __volatile__ ("" : : "r" (__sc2)) + +/* We can't tell whether a3 is going to be eliminated in the enclosing + function, so we have to assume it isn't. We first load the value + of any arguments into their registers, except for a3 itself, that + may be needed to load the value of the other arguments. Then, we + save a3's value in some other register, and load the argument value + into a3. We have to force both a3 and its copy to be live in + different registers at the same time, to avoid having the copy + spilled and the value reloaded into the same register, in which + case we'd be unable to get the value of a3 back, should the stack + slot reference be (offset,a3). */ +#define inline_syscall3(name,arg1,arg2,arg3) \ +long __sc3v = (long) (arg3); \ +register long __sc1 asm ("a0") = (long) (arg1); \ +register long __sc2 asm ("d1") = (long) (arg2); \ +register long __sc3 asm ("a3") = __sc3; \ +register long __sc3c; \ +__asm__ __volatile__ ("mov %1,%0" : "=&r" (__sc3c) : "r" (__sc3)); \ +__sc3 = __sc3v; \ +__asm__ __volatile__ ("" : : "r" (__sc3c), "r" (__sc3)); \ +inline_syscall0 (name); \ +__sc3 = __sc3c; \ +__asm__ __volatile__ ("" : : "r" (__sc3), "r" (__sc2), "r" (__sc1)) + +#ifdef PIC +/* Since a2 is the PIC register, it requires similar handling as a3 + when we're generating PIC, as a2's value may be needed to load + arguments whose values live in global variables. The difference is + that we don't need to require its value to be live in a register; + it may well be in a stack slot, as long as we save it before + clobbering a3 and restore it after restoring a3. */ +#define inline_syscall4(name,arg1,arg2,arg3,arg4) \ +long __sc4v = (long) (arg4); \ +long __sc3v = (long) (arg3); \ +register long __sc1 asm ("a0") = (long) (arg1); \ +register long __sc2 asm ("d1") = (long) (arg2); \ +register long __sc3 asm ("a3") = __sc3; \ +register long __sc3c; \ +register long __sc4 asm ("a2") = __sc4; \ +long __sc4c = __sc4; \ +__sc4 = __sc4v; \ +__asm__ __volatile__ ("mov %1,%0" : "=&r" (__sc3c) : "r" (__sc3)); \ +__sc3 = __sc3v; \ +__asm__ __volatile__ ("" : : "r" (__sc3c), "r" (__sc3), "r" (__sc4)); \ +inline_syscall0 (name); \ +__sc3 = __sc3c; \ +__sc4 = __sc4c; \ +__asm__ __volatile__ ("" : : "r" (__sc4), "r" (__sc3), \ + "r" (__sc2), "r" (__sc1)) +#else +#define inline_syscall4(name,arg1,arg2,arg3,arg4) \ +register long __sc4 asm ("a2") = (long) (arg4); \ +inline_syscall3 (name,(arg1),(arg2),(arg3)); \ +__asm__ __volatile__ ("" : : "r" (__sc4)) +#endif + +#define inline_syscall5(name,arg1,arg2,arg3,arg4,arg5) \ +register long __sc5 asm ("d3") = (long) (arg5); \ +inline_syscall4 (name,(arg1),(arg2),(arg3),(arg4)); \ +__asm__ __volatile__ ("" : : "r" (__sc5)) + +#define inline_syscall6(name,arg1,arg2,arg3,arg4,arg5,arg6) \ +register long __sc6 asm ("d2") = (long) (arg6); \ +inline_syscall5 (name,(arg1),(arg2),(arg3),(arg4),(arg5)); \ +__asm__ __volatile__ ("" : : "r" (__sc6)) + +#endif /* __ASSEMBLER__ */ + +#endif /* linux/am33/sysdep.h */ |