gcc/config/rs6000/linux.h

   1 /* Definitions of target machine for GNU compiler,
   2    for PowerPC machines running Linux.
   3    Copyright (C) 1996-2023 Free Software Foundation, Inc.
   4    Contributed by Michael Meissner (meissner@cygnus.com).
   5
   6    This file is part of GCC.
   7
   8    GCC is free software; you can redistribute it and/or modify it
   9    under the terms of the GNU General Public License as published
  10    by the Free Software Foundation; either version 3, or (at your
  11    option) any later version.
  12
  13    GCC is distributed in the hope that it will be useful, but WITHOUT
  14    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  15    or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
  16    License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with GCC; see the file COPYING3.  If not see
  20    <http://www.gnu.org/licenses/>.  */
  21
  22 /* Linux doesn't support saving and restoring 64-bit regs in a 32-bit
  23    process.  */
  24 #define OS_MISSING_POWERPC64 1
  25
  26 /* We use glibc _mcount for profiling.  */
  27 #define NO_PROFILE_COUNTERS 1
  28
  29 #ifdef SINGLE_LIBC
  30 #define OPTION_GLIBC_P(opts)    (DEFAULT_LIBC == LIBC_GLIBC)
  31 #define OPTION_UCLIBC_P(opts)   (DEFAULT_LIBC == LIBC_UCLIBC)
  32 #define OPTION_BIONIC_P(opts)   (DEFAULT_LIBC == LIBC_BIONIC)
  33 #undef OPTION_MUSL_P
  34 #define OPTION_MUSL_P(opts)     (DEFAULT_LIBC == LIBC_MUSL)
  35 #else
  36 #define OPTION_GLIBC_P(opts)    ((opts)->x_linux_libc == LIBC_GLIBC)
  37 #define OPTION_UCLIBC_P(opts)   ((opts)->x_linux_libc == LIBC_UCLIBC)
  38 #define OPTION_BIONIC_P(opts)   ((opts)->x_linux_libc == LIBC_BIONIC)
  39 #undef OPTION_MUSL_P
  40 #define OPTION_MUSL_P(opts)     ((opts)->x_linux_libc == LIBC_MUSL)
  41 #endif
  42 #define OPTION_GLIBC            OPTION_GLIBC_P (&global_options)
  43 #define OPTION_UCLIBC           OPTION_UCLIBC_P (&global_options)
  44 #define OPTION_BIONIC           OPTION_BIONIC_P (&global_options)
  45 #undef OPTION_MUSL
  46 #define OPTION_MUSL             OPTION_MUSL_P (&global_options)
  47
  48 /* Determine what functions are present at the runtime;
  49    this includes full c99 runtime and sincos.  */
  50 #undef TARGET_LIBC_HAS_FUNCTION
  51 #define TARGET_LIBC_HAS_FUNCTION linux_libc_has_function
  52
  53 #undef TARGET_LIBM_FUNCTION_MAX_ERROR
  54 #define TARGET_LIBM_FUNCTION_MAX_ERROR rs6000_linux_libm_function_max_error
  55
  56 #undef  TARGET_OS_CPP_BUILTINS
  57 #define TARGET_OS_CPP_BUILTINS()                        \
  58   do                                                    \
  59     {                                                   \
  60       if (strcmp (rs6000_abi_name, "linux") == 0)       \
  61         GNU_USER_TARGET_OS_CPP_BUILTINS();              \
  62       builtin_define_std ("PPC");                       \
  63       builtin_define_std ("powerpc");                   \
  64       builtin_assert ("cpu=powerpc");                   \
  65       builtin_assert ("machine=powerpc");               \
  66       TARGET_OS_SYSV_CPP_BUILTINS ();                   \
  67     }                                                   \
  68   while (0)
  69
  70 #undef  CPP_OS_DEFAULT_SPEC
  71 #define CPP_OS_DEFAULT_SPEC "%(cpp_os_linux)"
  72
  73 #undef  LINK_SHLIB_SPEC
  74 #define LINK_SHLIB_SPEC "%{shared:-shared} %{!shared: %{static:-static}} \
  75   %{static-pie:-static -pie --no-dynamic-linker -z text}"
  76
  77 #undef  LIB_DEFAULT_SPEC
  78 #define LIB_DEFAULT_SPEC "%(lib_linux)"
  79
  80 #undef  STARTFILE_DEFAULT_SPEC
  81 #define STARTFILE_DEFAULT_SPEC "%(startfile_linux)"
  82
  83 #undef  ENDFILE_DEFAULT_SPEC
  84 #define ENDFILE_DEFAULT_SPEC "%(endfile_linux)"
  85
  86 #undef  LINK_START_DEFAULT_SPEC
  87 #define LINK_START_DEFAULT_SPEC "%(link_start_linux)"
  88
  89 #undef  LINK_OS_DEFAULT_SPEC
  90 #define LINK_OS_DEFAULT_SPEC "%(link_os_linux)"
  91
  92 #undef  DEFAULT_ASM_ENDIAN
  93 #if (TARGET_DEFAULT & MASK_LITTLE_ENDIAN)
  94 #define DEFAULT_ASM_ENDIAN " -mlittle"
  95 #define LINK_OS_LINUX_EMUL ENDIAN_SELECT(" -m elf32ppclinux",   \
  96                                          " -m elf32lppclinux",  \
  97                                          " -m elf32lppclinux")
  98 #else
  99 #define DEFAULT_ASM_ENDIAN " -mbig"
 100 #define LINK_OS_LINUX_EMUL ENDIAN_SELECT(" -m elf32ppclinux",   \
 101                                          " -m elf32lppclinux",  \
 102                                          " -m elf32ppclinux")
 103 #endif
 104
 105 #undef LINK_OS_LINUX_SPEC
 106 #define LINK_OS_LINUX_SPEC LINK_OS_LINUX_EMUL " %{!shared: %{!static: \
 107   %{!static-pie: \
 108     %{rdynamic:-export-dynamic} \
 109     -dynamic-linker " GNU_USER_DYNAMIC_LINKER "}}}"
 110
 111 /* For backward compatibility, we must continue to use the AIX
 112    structure return convention.  */
 113 #undef  DRAFT_V4_STRUCT_RET
 114 #define DRAFT_V4_STRUCT_RET 1
 115
 116 /* We are 32-bit all the time, so optimize a little.  */
 117 #undef TARGET_64BIT
 118 #define TARGET_64BIT 0
 119
 120 /* We don't need to generate entries in .fixup, except when
 121    -mrelocatable or -mrelocatable-lib is given.  */
 122 #undef RELOCATABLE_NEEDS_FIXUP
 123 #define RELOCATABLE_NEEDS_FIXUP \
 124   (rs6000_isa_flags & rs6000_isa_flags_explicit & OPTION_MASK_RELOCATABLE)
 125
 126 #undef  RS6000_ABI_NAME
 127 #define RS6000_ABI_NAME "linux"
 128
 129 #ifdef TARGET_LIBC_PROVIDES_SSP
 130 /* ppc32 glibc provides __stack_chk_guard in -0x7008(2).  */
 131 #define TARGET_THREAD_SSP_OFFSET        -0x7008
 132 #endif
 133
 134 #define POWERPC_LINUX
 135
 136 /* ppc linux has 128-bit long double support in glibc 2.4 and later.  */
 137 #ifdef TARGET_DEFAULT_LONG_DOUBLE_128
 138 #define RS6000_DEFAULT_LONG_DOUBLE_SIZE 128
 139 #endif
 140
 141 /* Static stack checking is supported by means of probes.  */
 142 #define STACK_CHECK_STATIC_BUILTIN 1
 143
 144 /* Software floating point support for exceptions and rounding modes
 145    depends on the C library in use.  */
 146 #undef TARGET_FLOAT_EXCEPTIONS_ROUNDING_SUPPORTED_P
 147 #define TARGET_FLOAT_EXCEPTIONS_ROUNDING_SUPPORTED_P \
 148   rs6000_linux_float_exceptions_rounding_supported_p
 149
 150 /* Support for TARGET_ATOMIC_ASSIGN_EXPAND_FENV without FPRs depends
 151    on glibc 2.19 or greater.  */
 152 #if TARGET_GLIBC_MAJOR > 2 \
 153   || (TARGET_GLIBC_MAJOR == 2 && TARGET_GLIBC_MINOR >= 19)
 154 #define RS6000_GLIBC_ATOMIC_FENV 1
 155 #endif