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Diffstat (limited to 'libc/sysdeps/linux/hppa/sysdep.h')
| -rw-r--r-- | libc/sysdeps/linux/hppa/sysdep.h | 356 |
1 files changed, 356 insertions, 0 deletions
diff --git a/libc/sysdeps/linux/hppa/sysdep.h b/libc/sysdeps/linux/hppa/sysdep.h new file mode 100644 index 000000000..57b0cba9b --- /dev/null +++ b/libc/sysdeps/linux/hppa/sysdep.h @@ -0,0 +1,356 @@ +/* Assembler macros for PA-RISC. + Copyright (C) 1999-2018 Free Software Foundation, Inc. + Contributed by Ulrich Drepper, <drepper@cygnus.com>, August 1999. + Linux/PA-RISC changes by Philipp Rumpf, <prumpf@tux.org>, March 2000. + + 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_HPPA_SYSDEP_H +#define _LINUX_HPPA_SYSDEP_H 1 + +#include <common/sysdep.h> +#include <sys/syscall.h> + +/* In order to get __set_errno() definition in INLINE_SYSCALL. */ +#ifndef __ASSEMBLER__ +#include <errno.h> +#endif + +#undef ASM_LINE_SEP +#define ASM_LINE_SEP ! + +#undef SYS_ify +#define SYS_ify(syscall_name) (__NR_##syscall_name) + +/* The vfork, fork, and clone syscalls clobber r19 + * and r21. We list r21 as either clobbered or as an + * input to a 6-argument syscall. We must save and + * restore r19 in both PIC and non-PIC cases. + */ +/* WARNING: TREG must be a callee saves register so + that it doesn't have to be restored after a call + to another function */ +#define TREG 4 +#define SAVE_PIC(SREG) \ + copy %r19, SREG +#define LOAD_PIC(LREG) \ + copy LREG , %r19 +/* Inline assembly defines */ +#define TREG_ASM "%r4" /* Cant clobber r3, it holds framemarker */ +#define SAVE_ASM_PIC " copy %%r19, %" TREG_ASM "\n" +#define LOAD_ASM_PIC " copy %" TREG_ASM ", %%r19\n" +#define CLOB_TREG TREG_ASM , +#define PIC_REG_DEF register unsigned long __r19 asm("r19"); +#define PIC_REG_USE , "r" (__r19) + +#ifdef __ASSEMBLER__ + +/* Syntactic details of assembler. */ + +#define ALIGNARG(log2) log2 + +/* 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 + +/* 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 safely + 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*/ + +/* Argument manipulation from the stack for preparing to + make a syscall */ + +#define DOARGS_0 /* nothing */ +#define DOARGS_1 /* nothing */ +#define DOARGS_2 /* nothing */ +#define DOARGS_3 /* nothing */ +#define DOARGS_4 /* nothing */ +#define DOARGS_5 ldw -52(%sp), %r22 ASM_LINE_SEP +#define DOARGS_6 DOARGS_5 ldw -56(%sp), %r21 ASM_LINE_SEP + +#define UNDOARGS_0 /* nothing */ +#define UNDOARGS_1 /* nothing */ +#define UNDOARGS_2 /* nothing */ +#define UNDOARGS_3 /* nothing */ +#define UNDOARGS_4 /* nothing */ +#define UNDOARGS_5 /* nothing */ +#define UNDOARGS_6 /* nothing */ + +/* Define an entry point visible from C. + + There is currently a bug in gdb which prevents us from specifying + incomplete stabs information. Fake some entries here which specify + the current source file. */ +#undef ENTRY +#define ENTRY(name) \ + .text ASM_LINE_SEP \ + .align ALIGNARG(4) ASM_LINE_SEP \ + .export C_SYMBOL_NAME(name) ASM_LINE_SEP \ + .type C_SYMBOL_NAME(name),@function ASM_LINE_SEP \ + cfi_startproc ASM_LINE_SEP \ + C_LABEL(name) ASM_LINE_SEP \ + .PROC ASM_LINE_SEP \ + .CALLINFO FRAME=64,CALLS,SAVE_RP,ENTRY_GR=3 ASM_LINE_SEP \ + .ENTRY ASM_LINE_SEP \ + /* SAVE_RP says we do */ ASM_LINE_SEP \ + stw %rp, -20(%sr0,%sp) ASM_LINE_SEP \ + .cfi_offset 2, -20 ASM_LINE_SEP \ + /*FIXME: Call mcount? (carefull with stack!) */ + +/* Some syscall wrappers do not call other functions, and + hence are classified as leaf, so add NO_CALLS for gdb */ +#define ENTRY_LEAF(name) \ + .text ASM_LINE_SEP \ + .align ALIGNARG(4) ASM_LINE_SEP \ + .export C_SYMBOL_NAME(name) ASM_LINE_SEP \ + .type C_SYMBOL_NAME(name),@function ASM_LINE_SEP \ + cfi_startproc ASM_LINE_SEP \ + C_LABEL(name) ASM_LINE_SEP \ + .PROC ASM_LINE_SEP \ + .CALLINFO FRAME=64,NO_CALLS,SAVE_RP,ENTRY_GR=3 ASM_LINE_SEP \ + .ENTRY ASM_LINE_SEP \ + /* SAVE_RP says we do */ ASM_LINE_SEP \ + stw %rp, -20(%sr0,%sp) ASM_LINE_SEP \ + .cfi_offset 2, -20 ASM_LINE_SEP \ + /*FIXME: Call mcount? (carefull with stack!) */ + +#undef END +#define END(name) \ + .EXIT ASM_LINE_SEP \ + .PROCEND ASM_LINE_SEP \ + cfi_endproc ASM_LINE_SEP \ +.size C_SYMBOL_NAME(name), .-C_SYMBOL_NAME(name) ASM_LINE_SEP + +/* If compiled for profiling, call `mcount' at the start + of each function. No, don't bother. gcc will put the + call in for us. */ +#define CALL_MCOUNT /* Do nothing. */ + +/* syscall wrappers consist of + #include <sysdep.h> + PSEUDO(...) + ret + PSEUDO_END(...) + + which means + ENTRY(name) + DO_CALL(...) + bv,n 0(2) +*/ + +#undef PSEUDO +#define PSEUDO(name, syscall_name, args) \ + ENTRY (name) ASM_LINE_SEP \ + /* If necc. load args from stack */ ASM_LINE_SEP \ + DOARGS_##args ASM_LINE_SEP \ + DO_CALL (syscall_name, args) ASM_LINE_SEP \ + UNDOARGS_##args ASM_LINE_SEP + +#define ret \ + /* Return value set by ERRNO code */ ASM_LINE_SEP \ + bv,n 0(2) ASM_LINE_SEP + +#undef PSEUDO_END +#define PSEUDO_END(name) \ + END (name) + +/* We don't set the errno on the return from the syscall */ +#define PSEUDO_NOERRNO(name, syscall_name, args) \ + ENTRY_LEAF (name) ASM_LINE_SEP \ + DOARGS_##args ASM_LINE_SEP \ + DO_CALL_NOERRNO (syscall_name, args) ASM_LINE_SEP \ + UNDOARGS_##args ASM_LINE_SEP + +#define ret_NOERRNO ret + +#undef PSEUDO_END_NOERRNO +#define PSEUDO_END_NOERRNO(name) \ + END (name) + +/* This has to return the error value */ +#undef PSEUDO_ERRVAL +#define PSEUDO_ERRVAL(name, syscall_name, args) \ + ENTRY_LEAF (name) ASM_LINE_SEP \ + DOARGS_##args ASM_LINE_SEP \ + DO_CALL_ERRVAL (syscall_name, args) ASM_LINE_SEP \ + UNDOARGS_##args ASM_LINE_SEP + +#define ret_ERRVAL ret + +#undef PSEUDO_END_ERRVAL +#define PSEUDO_END_ERRVAL(name) \ + END(name) + +#undef JUMPTARGET +#define JUMPTARGET(name) name +#define SYSCALL_PIC_SETUP /* Nothing. */ + + +/* FIXME: This comment is not true. + * All the syscall assembly macros rely on finding the appropriate + SYSCALL_ERROR_LABEL or rather HANDLER. */ + +/* int * __errno_location(void) so you have to store your value + into the return address! */ +#define DEFAULT_SYSCALL_ERROR_HANDLER \ + .import __errno_location,code ASM_LINE_SEP \ + /* branch to errno handler */ ASM_LINE_SEP \ + bl __errno_location,%rp ASM_LINE_SEP + +/* Here are the myriad of configuration options that the above can + work for... what we've done is provide the framework for future + changes if required to each section */ + +#ifdef __PIC__ +# if defined _LIBC_REENTRANT +# define SYSCALL_ERROR_HANDLER DEFAULT_SYSCALL_ERROR_HANDLER +# else /* !_LIBC_REENTRANT */ +# define SYSCALL_ERROR_HANDLER DEFAULT_SYSCALL_ERROR_HANDLER +# endif /* _LIBC_REENTRANT */ +#else +# ifndef _LIBC_REENTRANT +# define SYSCALL_ERROR_HANDLER DEFAULT_SYSCALL_ERROR_HANDLER +# else +# define SYSCALL_ERROR_HANDLER DEFAULT_SYSCALL_ERROR_HANDLER +# endif +#endif + + +/* Linux takes system call arguments in registers: + syscall number gr20 + arg 1 gr26 + arg 2 gr25 + arg 3 gr24 + arg 4 gr23 + arg 5 gr22 + arg 6 gr21 + + The compiler calls us by the C convention: + syscall number in the DO_CALL macro + arg 1 gr26 + arg 2 gr25 + arg 3 gr24 + arg 4 gr23 + arg 5 -52(sp) + arg 6 -56(sp) + + gr22 and gr21 are caller-saves, so we can just load the arguments + there and generally be happy. */ + +/* the cmpb...no_error code below inside DO_CALL + * is intended to mimic the if (__sys_res...) + * code inside INLINE_SYSCALL + */ +#define NO_ERROR -0x1000 + +#undef DO_CALL +#define DO_CALL(syscall_name, args) \ + /* Create a frame */ ASM_LINE_SEP \ + stwm TREG, 64(%sp) ASM_LINE_SEP \ + .cfi_def_cfa_offset -64 ASM_LINE_SEP \ + .cfi_offset TREG, 0 ASM_LINE_SEP \ + stw %sp, -4(%sp) ASM_LINE_SEP \ + stw %r19, -32(%sp) ASM_LINE_SEP \ + .cfi_offset 19, 32 ASM_LINE_SEP \ + /* Save r19 */ ASM_LINE_SEP \ + SAVE_PIC(TREG) ASM_LINE_SEP \ + /* Do syscall, delay loads # */ ASM_LINE_SEP \ + ble 0x100(%sr2,%r0) ASM_LINE_SEP \ + ldi SYS_ify (syscall_name), %r20 ASM_LINE_SEP \ + ldi NO_ERROR,%r1 ASM_LINE_SEP \ + cmpb,>>=,n %r1,%ret0,L(pre_end) ASM_LINE_SEP \ + /* Restore r19 from TREG */ ASM_LINE_SEP \ + LOAD_PIC(TREG) /* delay */ ASM_LINE_SEP \ + SYSCALL_ERROR_HANDLER ASM_LINE_SEP \ + /* Use TREG for temp storage */ ASM_LINE_SEP \ + copy %ret0, TREG /* delay */ ASM_LINE_SEP \ + /* OPTIMIZE: Don't reload r19 */ ASM_LINE_SEP \ + /* do a -1*syscall_ret0 */ ASM_LINE_SEP \ + sub %r0, TREG, TREG ASM_LINE_SEP \ + /* Store into errno location */ ASM_LINE_SEP \ + stw TREG, 0(%sr0,%ret0) ASM_LINE_SEP \ + /* return -1 as error */ ASM_LINE_SEP \ + ldo -1(%r0), %ret0 ASM_LINE_SEP \ +L(pre_end): ASM_LINE_SEP \ + /* Restore our frame, restoring TREG */ ASM_LINE_SEP \ + ldwm -64(%sp), TREG ASM_LINE_SEP \ + /* Restore return pointer */ ASM_LINE_SEP \ + ldw -20(%sp),%rp ASM_LINE_SEP + +/* We do nothing with the return, except hand it back to someone else */ +#undef DO_CALL_NOERRNO +#define DO_CALL_NOERRNO(syscall_name, args) \ + /* No need to store r19 */ ASM_LINE_SEP \ + ble 0x100(%sr2,%r0) ASM_LINE_SEP \ + ldi SYS_ify (syscall_name), %r20 ASM_LINE_SEP \ + /* Caller will restore r19 */ ASM_LINE_SEP + +/* Here, we return the ERRVAL in assembly, note we don't call the + error handler function, but we do 'negate' the return _IF_ + it's an error. Not sure if this is the right semantic. */ + +#undef DO_CALL_ERRVAL +#define DO_CALL_ERRVAL(syscall_name, args) \ + /* No need to store r19 */ ASM_LINE_SEP \ + ble 0x100(%sr2,%r0) ASM_LINE_SEP \ + ldi SYS_ify (syscall_name), %r20 ASM_LINE_SEP \ + /* Caller will restore r19 */ ASM_LINE_SEP \ + ldi NO_ERROR,%r1 ASM_LINE_SEP \ + cmpb,>>=,n %r1,%ret0,0f ASM_LINE_SEP \ + sub %r0, %ret0, %ret0 ASM_LINE_SEP \ +0: ASM_LINE_SEP + + +#else + +/* GCC has to be warned that a syscall may clobber all the ABI + registers listed as "caller-saves", see page 8, Table 2 + in section 2.2.6 of the PA-RISC RUN-TIME architecture + document. However! r28 is the result and will conflict with + the clobber list so it is left out. Also the input arguments + registers r20 -> r26 will conflict with the list so they + are treated specially. Although r19 is clobbered by the syscall + we cannot say this because it would violate ABI, thus we say + TREG is clobbered and use that register to save/restore r19 + across the syscall. */ + +#define CALL_CLOB_REGS "%r1", "%r2", CLOB_TREG \ + "%r20", "%r29", "%r31" + +#endif /* __ASSEMBLER__ */ + +#endif /* _LINUX_HPPA_SYSDEP_H */ |