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/* 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, see
<http://www.gnu.org/licenses/>. */
#ifndef _LINUX_XTENSA_SYSDEP_H
#define _LINUX_XTENSA_SYSDEP_H 1
#include <common/sysdep.h>
#include <sys/syscall.h>
#ifdef __ASSEMBLER__
#define ALIGNARG(log2) 1 << log2
#define ASM_TYPE_DIRECTIVE(name, typearg) .type name, typearg
#define ASM_SIZE_DIRECTIVE(name) .size name, . - name
#if defined(__XTENSA_WINDOWED_ABI__)
#define abi_entry(reg, frame_size) entry reg, frame_size
#define abi_ret retw
#elif defined(__XTENSA_CALL0_ABI__)
#define abi_entry(reg, frame_size)
#define abi_ret ret
#else
#error Unsupported Xtensa ABI
#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) \
abi_entry(sp, FRAMESIZE); \
CALL_MCOUNT
#define HIDDEN_ENTRY(name) \
ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME(name); \
.hidden C_SYMBOL_NAME(name); \
ASM_TYPE_DIRECTIVE (C_SYMBOL_NAME(name), @function); \
.align ALIGNARG(2); \
LITERAL_POSITION; \
C_LABEL(name) \
abi_entry(sp, FRAMESIZE); \
CALL_MCOUNT
#undef END
#define END(name) ASM_SIZE_DIRECTIVE(name)
/* Local label name for asm code. */
#ifndef L
# ifdef HAVE_ELF
# define L(name) .L##name
# else
# define L(name) name
# endif
#endif
/* 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
#ifndef FRAMESIZE
#if defined(__XTENSA_WINDOWED_ABI__)
#define FRAMESIZE 16
#elif defined(__XTENSA_CALL0_ABI__)
#define FRAMESIZE 0
#else
#error Unsupported Xtensa ABI
#endif
#endif
#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 abi_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); \
neg a2, a2
#undef PSEUDO_END_ERRVAL
#define PSEUDO_END_ERRVAL(name) \
END (name)
#undef ret_ERRVAL
#define ret_ERRVAL abi_ret
#if defined _LIBC_REENTRANT
# if defined 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 */
#if defined(__XTENSA_WINDOWED_ABI__)
# 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;
#elif defined(__XTENSA_CALL0_ABI__)
# define SYSCALL_ERROR_HANDLER \
0: neg a2, a2; \
addi a1, a1, -16; \
s32i a0, a1, 0; \
s32i a2, a1, 4; \
movi a0, __errno_location@PLT; \
callx0 a0; \
l32i a0, a1, 0; \
l32i a3, a1, 4; \
addi a1, a1, 16; \
s32i a3, a2, 0; \
movi a2, -1; \
j .Lpseudo_end;
#else
#error Unsupported Xtensa ABI
#endif
# 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__ */
/* Pointer mangling is not yet supported for Xtensa. */
#define PTR_MANGLE(var) (void) (var)
#define PTR_DEMANGLE(var) (void) (var)
#endif /* _LINUX_XTENSA_SYSDEP_H */
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