diff options
Diffstat (limited to 'libc/sysdeps/linux/xtensa/sysdep.h')
| -rw-r--r-- | libc/sysdeps/linux/xtensa/sysdep.h | 160 |
1 files changed, 160 insertions, 0 deletions
diff --git a/libc/sysdeps/linux/xtensa/sysdep.h b/libc/sysdeps/linux/xtensa/sysdep.h new file mode 100644 index 000000000..5708a8114 --- /dev/null +++ b/libc/sysdeps/linux/xtensa/sysdep.h @@ -0,0 +1,160 @@ +/* Assembler macros for Xtensa processors. + Copyright (C) 2001, 2007 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + 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., 51 Franklin Street - Fifth Floor, + Boston, MA 02110-1301, USA. */ + +#ifdef __ASSEMBLER__ + +#define ALIGNARG(log2) 1 << log2 +#define ASM_TYPE_DIRECTIVE(name, typearg) .type name, typearg +#define ASM_SIZE_DIRECTIVE(name) .size name, . - name + +#ifdef __STDC__ +#define C_LABEL(name) name : +#else +#define C_LABEL(name) name/**/: +#endif + +#define ENTRY(name) \ + ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME(name); \ + ASM_TYPE_DIRECTIVE (C_SYMBOL_NAME(name), @function); \ + .align ALIGNARG(2); \ + LITERAL_POSITION; \ + C_LABEL(name) \ + entry sp, FRAMESIZE; \ + CALL_MCOUNT + +#undef END +#define END(name) ASM_SIZE_DIRECTIVE(name) + +/* Define a macro for this directive so it can be removed in a few places. */ +#define LITERAL_POSITION .literal_position + +#undef JUMPTARGET +#ifdef PIC +/* The "@PLT" suffix is currently a no-op for non-shared linking, but + it doesn't hurt to use it conditionally for PIC code in case that + changes someday. */ +#define JUMPTARGET(name) name##@PLT +#else +#define JUMPTARGET(name) name +#endif + +#define FRAMESIZE 16 +#define CALL_MCOUNT /* Do nothing. */ + + +/* 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 a2 + 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 safely + test with -4095. */ + +/* We don't want the label for the error handler to be global when we define + it here. */ +#define SYSCALL_ERROR_LABEL 0f + +#undef PSEUDO +#define PSEUDO(name, syscall_name, args) \ + .text; \ + ENTRY (name) \ + DO_CALL (syscall_name, args); \ + movi a4, -4095; \ + bgeu a2, a4, SYSCALL_ERROR_LABEL; \ + .Lpseudo_end: + +#undef PSEUDO_END +#define PSEUDO_END(name) \ + SYSCALL_ERROR_HANDLER \ + END (name) + +#undef PSEUDO_NOERRNO +#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) + +#undef ret_NOERRNO +#define ret_NOERRNO retw + +/* 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); \ + neg a2, a2 + +#undef PSEUDO_END_ERRVAL +#define PSEUDO_END_ERRVAL(name) \ + END (name) + +#define ret_ERRVAL retw + +#if RTLD_PRIVATE_ERRNO +# define SYSCALL_ERROR_HANDLER \ +0: movi a4, rtld_errno; \ + neg a2, a2; \ + s32i a2, a4, 0; \ + movi a2, -1; \ + j .Lpseudo_end; + +#elif defined _LIBC_REENTRANT + +# if USE___THREAD +# ifndef NOT_IN_libc +# define SYSCALL_ERROR_ERRNO __libc_errno +# else +# define SYSCALL_ERROR_ERRNO errno +# endif +# define SYSCALL_ERROR_HANDLER \ +0: rur a4, THREADPTR; \ + movi a3, SYSCALL_ERROR_ERRNO@TPOFF; \ + neg a2, a2; \ + add a4, a4, a3; \ + s32i a2, a4, 0; \ + movi a2, -1; \ + j .Lpseudo_end; +# else /* !USE___THREAD */ +# define SYSCALL_ERROR_HANDLER \ +0: neg a2, a2; \ + mov a6, a2; \ + movi a4, __errno_location@PLT; \ + callx4 a4; \ + s32i a2, a6, 0; \ + movi a2, -1; \ + j .Lpseudo_end; +# endif /* !USE___THREAD */ +#else /* !_LIBC_REENTRANT */ +#define SYSCALL_ERROR_HANDLER \ +0: movi a4, errno; \ + neg a2, a2; \ + s32i a2, a4, 0; \ + movi a2, -1; \ + j .Lpseudo_end; +#endif /* _LIBC_REENTRANT */ + +#endif /* __ASSEMBLER__ */ |