/* Assembler macros for SH. Copyright (C) 1999, 2000, 2005 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. */ #include <common/sysdep.h> #include <features.h> #include <libc-internal.h> #ifdef __ASSEMBLER__ /* Syntactic details of assembler. */ #define ALIGNARG(log2) log2 /* For ELF we need the `.type' directive to make shared libs work right. */ #define ASM_TYPE_DIRECTIVE(name,typearg) .type name,@##typearg; #define ASM_SIZE_DIRECTIVE(name) .size name,.-name #ifdef SHARED #define PLTJMP(_x) _x##@PLT #else #define PLTJMP(_x) _x #endif /* Define an entry point visible from C. */ #define ENTRY(name) \ ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME(name); \ ASM_TYPE_DIRECTIVE (C_SYMBOL_NAME(name),function) \ .align ALIGNARG(5); \ C_LABEL(name) \ cfi_startproc; \ CALL_MCOUNT #undef END #define END(name) \ cfi_endproc; \ ASM_SIZE_DIRECTIVE(C_SYMBOL_NAME(name)) /* If compiled for profiling, call `mcount' at the start of each function. */ #ifdef PROF #define CALL_MCOUNT \ mov.l 1f,r1; \ sts.l pr,@-r15; \ cfi_adjust_cfa_offset (4); \ cfi_rel_offset (pr, 0); \ mova 2f,r0; \ jmp @r1; \ lds r0,pr; \ .align 2; \ 1: .long mcount; \ 2: lds.l @r15+,pr; \ cfi_adjust_cfa_offset (-4); \ cfi_restore (pr) #else #define CALL_MCOUNT /* Do nothing. */ #endif #ifdef __UCLIBC_UNDERSCORES__ /* Since C identifiers are not normally prefixed with an underscore on this system, the asm identifier `syscall_error' intrudes on the C name space. Make sure we use an innocuous name. */ #define syscall_error __syscall_error #define mcount _mcount #endif /* 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) #define ret rts ; nop /* The sh move insn is s, d. */ #define MOVE(x,y) mov x , y /* 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 R0 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. */ #define _IMM1 #-1 #define _IMM12 #-12 #undef PSEUDO #define PSEUDO(name, syscall_name, args) \ .text; \ ENTRY (name); \ DO_CALL (syscall_name, args); \ mov r0,r1; \ mov _IMM12,r2; \ shad r2,r1; \ not r1,r1; \ tst r1,r1; \ bf .Lpseudo_end; \ SYSCALL_ERROR_HANDLER; \ .Lpseudo_end: #undef PSEUDO_END #define PSEUDO_END(name) \ 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) #define ret_NOERRNO ret #define PSEUDO_ERRVAL(name, syscall_name, args) \ .text; \ ENTRY (name); \ DO_CALL (syscall_name, args); #undef PSEUDO_END_ERRVAL #define PSEUDO_END_ERRVAL(name) \ END (name) #define ret_ERRVAL ret #ifndef __PIC__ # define SYSCALL_ERROR_HANDLER \ mov.l 0f,r1; \ jmp @r1; \ mov r0,r4; \ .align 2; \ 0: .long __syscall_error #include <libc/sysdeps/linux/sh/syscall_error.S> #else # ifdef RTLD_PRIVATE_ERRNO # define SYSCALL_ERROR_HANDLER \ neg r0,r1; \ mov.l 0f,r12; \ mova 0f,r0; \ add r0,r12; \ mov.l 1f,r0; \ mov.l r1,@(r0,r12) bra .Lpseudo_end; \ mov _IMM1,r0; \ .align 2; \ 0: .long _GLOBAL_OFFSET_TABLE_; \ 1: .long rtld_errno@GOTOFF # 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 \ neg r0,r1; \ mov r12,r2; \ mov.l 0f,r12; \ mova 0f,r0; \ add r0,r12; \ mov.l 1f,r0; \ stc gbr, r4; \ mov.l @(r0,r12),r0; \ bra .Lskip; \ add r4,r0; \ .align 2; \ 1: .long SYSCALL_ERROR_ERRNO@GOTTPOFF; \ .Lskip: \ mov r2,r12; \ mov.l r1,@r0; \ bra .Lpseudo_end; \ mov _IMM1,r0; \ .align 2; \ 0: .long _GLOBAL_OFFSET_TABLE_ # else # define SYSCALL_ERROR_HANDLER \ neg r0,r1; \ mov.l r14,@-r15; \ mov.l r12,@-r15; \ mov.l r1,@-r15; \ mov.l 0f,r12; \ mova 0f,r0; \ add r0,r12; \ sts.l pr,@-r15; \ mov r15,r14; \ mov.l 1f,r1; \ bsrf r1; \ nop; \ 2: mov r14,r15; \ lds.l @r15+,pr; \ mov.l @r15+,r1; \ mov.l r1,@r0; \ mov.l @r15+,r12; \ mov.l @r15+,r14; \ bra .Lpseudo_end; \ mov _IMM1,r0; \ .align 2; \ 0: .long _GLOBAL_OFFSET_TABLE_; \ 1: .long PLTJMP(C_SYMBOL_NAME(__errno_location))-(2b-.) /* A quick note: it is assumed that the call to `__errno_location' does not modify the stack! */ # endif # else /* Store (-r0) into errno through the GOT. */ # define SYSCALL_ERROR_HANDLER \ neg r0,r1; \ mov r12,r2; \ mov.l 0f,r12; \ mova 0f,r0; \ add r0,r12; \ mov.l 1f,r0; \ mov.l @(r0,r12),r0; \ mov r2,r12; \ mov.l r1,@r0; \ bra .Lpseudo_end; \ mov _IMM1,r0; \ .align 2; \ 0: .long _GLOBAL_OFFSET_TABLE_; \ 1: .long errno@GOT # endif /* _LIBC_REENTRANT */ #endif /* __PIC__ */ # ifdef __SH4__ # define SYSCALL_INST_PAD \ or r0,r0; or r0,r0; or r0,r0; or r0,r0; or r0,r0 # else # define SYSCALL_INST_PAD # endif #define SYSCALL_INST0 trapa #0x10 #define SYSCALL_INST1 trapa #0x11 #define SYSCALL_INST2 trapa #0x12 #define SYSCALL_INST3 trapa #0x13 #define SYSCALL_INST4 trapa #0x14 #define SYSCALL_INST5 mov.l @(0,r15),r0; trapa #0x15 #define SYSCALL_INST6 mov.l @(0,r15),r0; mov.l @(4,r15),r1; trapa #0x16 #undef DO_CALL #define DO_CALL(syscall_name, args) \ mov.l 1f,r3; \ SYSCALL_INST##args; \ SYSCALL_INST_PAD; \ bra 2f; \ nop; \ .align 2; \ 1: .long SYS_ify (syscall_name); \ 2: #endif /* __ASSEMBLER__ */ /* Pointer mangling support. */ #if defined NOT_IN_libc && defined IS_IN_rtld /* We cannot use the thread descriptor because in ld.so we use setjmp earlier than the descriptor is initialized. Using a global variable is too complicated here since we have no PC-relative addressing mode. */ #else # ifdef __ASSEMBLER__ # define PTR_MANGLE(reg, tmp) \ stc gbr,tmp; mov.l @(POINTER_GUARD,tmp),tmp; xor tmp,reg # define PTR_MANGLE2(reg, tmp) xor tmp,reg # define PTR_DEMANGLE(reg, tmp) PTR_MANGLE (reg, tmp) # define PTR_DEMANGLE2(reg, tmp) PTR_MANGLE2 (reg, tmp) # else # define PTR_MANGLE(var) \ (var) = (void *) ((uintptr_t) (var) ^ THREAD_GET_POINTER_GUARD ()) # define PTR_DEMANGLE(var) PTR_MANGLE (var) # endif #endif