/* 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/>. */ #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 #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 #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) \ 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 defined 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 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 */ # 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__ */