sysdeps/unix/sysv/linux/ia64/sysdep.h

   1 /* Copyright (C) 1999, 2000, 2002 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Written by Jes Sorensen, <Jes.Sorensen@cern.ch>, April 1999.
   4    Based on code originally written by David Mosberger-Tang
   5
   6    The GNU C Library is free software; you can redistribute it and/or
   7    modify it under the terms of the GNU Lesser General Public
   8    License as published by the Free Software Foundation; either
   9    version 2.1 of the License, or (at your option) any later version.
  10
  11    The GNU C Library is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14    Lesser General Public License for more details.
  15
  16    You should have received a copy of the GNU Lesser General Public
  17    License along with the GNU C Library; if not, write to the Free
  18    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  19    02111-1307 USA.  */
  20
  21 #include <sysdeps/unix/sysdep.h>
  22 #include <sysdeps/ia64/sysdep.h>
  23
  24 /* For Linux we can use the system call table in the header file
  25         /usr/include/asm/unistd.h
  26    of the kernel.  But these symbols do not follow the SYS_* syntax
  27    so we have to redefine the `SYS_ify' macro here.  */
  28 #undef SYS_ify
  29 #ifdef __STDC__
  30 # define SYS_ify(syscall_name)  __NR_##syscall_name
  31 #else
  32 # define SYS_ify(syscall_name)  __NR_/**/syscall_name
  33 #endif
  34
  35 /* This is a kludge to make syscalls.list find these under the names
  36    pread and pwrite, since some kernel headers define those names
  37    and some define the *64 names for the same system calls.  */
  38 #if !defined __NR_pread && defined __NR_pread64
  39 # define __NR_pread __NR_pread64
  40 #endif
  41 #if !defined __NR_pwrite && defined __NR_pwrite64
  42 # define __NR_pwrite __NR_pwrite64
  43 #endif
  44
  45 #ifdef __ASSEMBLER__
  46
  47 #undef CALL_MCOUNT
  48 #ifdef PROF
  49 # define CALL_MCOUNT                                                    \
  50         .data;                                                          \
  51 1:      data8 0;        /* XXX fixme: use .xdata8 once labels work */   \
  52         .previous;                                                      \
  53         .prologue;                                                      \
  54         .save ar.pfs, r40;                                              \
  55         alloc out0 = ar.pfs, 8, 0, 4, 0;                                \
  56         mov out1 = gp;                                                  \
  57         .save rp, out2;                                                 \
  58         mov out2 = rp;                                                  \
  59         .body;                                                          \
  60         ;;                                                              \
  61         addl out3 = @ltoff(1b), gp;                                     \
  62         br.call.sptk.many rp = _mcount                                  \
  63         ;;
  64 #else
  65 # define CALL_MCOUNT    /* Do nothing. */
  66 #endif
  67
  68 /* Linux uses a negative return value to indicate syscall errors, unlike
  69    most Unices, which use the condition codes' carry flag.
  70
  71    Since version 2.1 the return value of a system call might be negative
  72    even if the call succeeded.  E.g., the `lseek' system call might return
  73    a large offset.  Therefore we must not anymore test for < 0, but test
  74    for a real error by making sure the value in %d0 is a real error
  75    number.  Linus said he will make sure the no syscall returns a value
  76    in -1 .. -4095 as a valid result so we can savely test with -4095.  */
  77
  78 /* We don't want the label for the error handler to be visible in the symbol
  79    table when we define it here.  */
  80 #define SYSCALL_ERROR_LABEL __syscall_error
  81
  82 #undef PSEUDO
  83 #define PSEUDO(name, syscall_name, args)        \
  84   ENTRY(name)                                   \
  85     DO_CALL (SYS_ify(syscall_name));            \
  86         cmp.eq p6,p0=-1,r10;                    \
  87 (p6)    br.cond.spnt.few __syscall_error;
  88
  89 #define DO_CALL(num)                            \
  90         mov r15=num;                            \
  91         break __BREAK_SYSCALL;
  92
  93 #undef PSEUDO_END
  94 #define PSEUDO_END(name)        .endp C_SYMBOL_NAME(name);
  95
  96 #undef END
  97 #define END(name)                                               \
  98         .size   C_SYMBOL_NAME(name), . - C_SYMBOL_NAME(name) ;  \
  99         .endp   C_SYMBOL_NAME(name)
 100
 101 #define ret                     br.ret.sptk.few b0
 102
 103 #else /* not __ASSEMBLER__ */
 104
 105 /* On IA-64 we have stacked registers for passing arguments.  The
 106    "out" registers end up being the called function's "in"
 107    registers.
 108
 109    Also, since we have plenty of registers we have two return values
 110    from a syscall.  r10 is set to -1 on error, whilst r8 contains the
 111    (non-negative) errno on error or the return value on success.
 112  */
 113 #undef INLINE_SYSCALL
 114 #define INLINE_SYSCALL(name, nr, args...)                       \
 115   ({                                                            \
 116     register long _r8 asm ("r8");                               \
 117     register long _r10 asm ("r10");                             \
 118     register long _r15 asm ("r15") = __NR_##name;               \
 119     long _retval;                                               \
 120     LOAD_ARGS_##nr (args);                                      \
 121     __asm __volatile ("break %3;;\n\t"                          \
 122                       : "=r" (_r8), "=r" (_r10), "=r" (_r15)    \
 123                       : "i" (__BREAK_SYSCALL), "2" (_r15)       \
 124                         ASM_ARGS_##nr                           \
 125                       : "memory" ASM_CLOBBERS_##nr);            \
 126     _retval = _r8;                                              \
 127     if (_r10 == -1)                                             \
 128       {                                                         \
 129         __set_errno (_retval);                                  \
 130         _retval = -1;                                           \
 131       }                                                         \
 132     _retval; })
 133
 134 #undef INTERNAL_SYSCALL
 135 #define INTERNAL_SYSCALL(name, nr, args...)                     \
 136   ({                                                            \
 137     register long _r8 asm ("r8");                               \
 138     register long _r10 asm ("r10");                             \
 139     register long _r15 asm ("r15") = __NR_##name;               \
 140     long _retval;                                               \
 141     LOAD_ARGS_##nr (args);                                      \
 142     __asm __volatile ("break %3;;\n\t"                          \
 143                       : "=r" (_r8), "=r" (_r10), "=r" (_r15)    \
 144                       : "i" (__BREAK_SYSCALL), "2" (_r15)       \
 145                         ASM_ARGS_##nr                           \
 146                       : "memory" ASM_CLOBBERS_##nr);            \
 147     _retval = _r8;                                              \
 148     if (_r10 == -1)                                             \
 149       _retval = -_retval;                                       \
 150     _retval; })
 151
 152 #undef INTERNAL_SYSCALL_ERROR_P
 153 #define INTERNAL_SYSCALL_ERROR_P(val)   ((unsigned long) (val) >= -4095UL)
 154
 155 #undef INTERNAL_SYSCALL_ERRNO
 156 #define INTERNAL_SYSCALL_ERRNO(val)     (-(val))
 157
 158 #define LOAD_ARGS_0()   do { } while (0)
 159 #define LOAD_ARGS_1(out0)                               \
 160   register long _out0 asm ("out0") = (long) (out0);     \
 161   LOAD_ARGS_0 ()
 162 #define LOAD_ARGS_2(out0, out1)                         \
 163   register long _out1 asm ("out1") = (long) (out1);     \
 164   LOAD_ARGS_1 (out0)
 165 #define LOAD_ARGS_3(out0, out1, out2)                   \
 166   register long _out2 asm ("out2") = (long) (out2);     \
 167   LOAD_ARGS_2 (out0, out1)
 168 #define LOAD_ARGS_4(out0, out1, out2, out3)             \
 169   register long _out3 asm ("out3") = (long) (out3);     \
 170   LOAD_ARGS_3 (out0, out1, out2)
 171 #define LOAD_ARGS_5(out0, out1, out2, out3, out4)       \
 172   register long _out4 asm ("out4") = (long) (out4);     \
 173   LOAD_ARGS_4 (out0, out1, out2, out3)
 174
 175 #define ASM_ARGS_0
 176 #define ASM_ARGS_1      ASM_ARGS_0, "r" (_out0)
 177 #define ASM_ARGS_2      ASM_ARGS_1, "r" (_out1)
 178 #define ASM_ARGS_3      ASM_ARGS_2, "r" (_out2)
 179 #define ASM_ARGS_4      ASM_ARGS_3, "r" (_out3)
 180 #define ASM_ARGS_5      ASM_ARGS_4, "r" (_out4)
 181
 182 #define ASM_CLOBBERS_0  ASM_CLOBBERS_1, "out0"
 183 #define ASM_CLOBBERS_1  ASM_CLOBBERS_2, "out1"
 184 #define ASM_CLOBBERS_2  ASM_CLOBBERS_3, "out2"
 185 #define ASM_CLOBBERS_3  ASM_CLOBBERS_4, "out3"
 186 #define ASM_CLOBBERS_4  ASM_CLOBBERS_5, "out4"
 187 #define ASM_CLOBBERS_5  , "out5", "out6", "out7",                       \
 188   /* Non-stacked integer registers, minus r8, r10, r15.  */             \
 189   "r2", "r3", "r9", "r11", "r12", "r13", "r14", "r16", "r17", "r18",    \
 190   "r19", "r20", "r21", "r22", "r23", "r24", "r25", "r26", "r27",        \
 191   "r28", "r29", "r30", "r31",                                           \
 192   /* Predicate registers.  */                                           \
 193   "p6", "p7", "p8", "p9", "p10", "p11", "p12", "p13", "p14", "p15",     \
 194   /* Non-rotating fp registers.  */                                     \
 195   "f6", "f7", "f8", "f9", "f10", "f11", "f12", "f13", "f14", "f15",     \
 196   /* Branch registers.  */                                              \
 197   "b6", "b7"
 198
 199 #endif /* not __ASSEMBLER__ */