gcc/common/config/rs6000/rs6000-common.c

   1 /* Common hooks for IBM RS/6000.
   2    Copyright (C) 1991-2019 Free Software Foundation, Inc.
   3
   4    This file is part of GCC.
   5
   6    GCC is free software; you can redistribute it and/or modify it
   7    under the terms of the GNU General Public License as published
   8    by the Free Software Foundation; either version 3, or (at your
   9    option) any later version.
  10
  11    GCC is distributed in the hope that it will be useful, but WITHOUT
  12    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  13    or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
  14    License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with GCC; see the file COPYING3.  If not see
  18    <http://www.gnu.org/licenses/>.  */
  19
  20 #include "config.h"
  21 #include "system.h"
  22 #include "coretypes.h"
  23 #include "diagnostic-core.h"
  24 #include "tm.h"
  25 #include "common/common-target.h"
  26 #include "common/common-target-def.h"
  27 #include "opts.h"
  28 #include "flags.h"
  29
  30 /* Implement TARGET_OPTION_OPTIMIZATION_TABLE.  */
  31 static const struct default_options rs6000_option_optimization_table[] =
  32   {
  33     /* Split multi-word types early.  */
  34     { OPT_LEVELS_ALL, OPT_fsplit_wide_types_early, NULL, 1 },
  35     /* Enable -fsched-pressure for first pass instruction scheduling.  */
  36     { OPT_LEVELS_1_PLUS, OPT_fsched_pressure, NULL, 1 },
  37     /* Enable -munroll-only-small-loops with -funroll-loops to unroll small
  38        loops at -O2 and above by default.  */
  39     { OPT_LEVELS_2_PLUS_SPEED_ONLY, OPT_funroll_loops, NULL, 1 },
  40     { OPT_LEVELS_2_PLUS_SPEED_ONLY, OPT_munroll_only_small_loops, NULL, 1 },
  41     /* -fweb and -frename-registers are useless in general for rs6000,
  42        turn them off.  */
  43     { OPT_LEVELS_ALL, OPT_fweb, NULL, 0 },
  44     { OPT_LEVELS_ALL, OPT_frename_registers, NULL, 0 },
  45
  46     /* Double growth factor to counter reduced min jump length.  */
  47     { OPT_LEVELS_ALL, OPT__param_max_grow_copy_bb_insns_, NULL, 16 },
  48     { OPT_LEVELS_NONE, 0, NULL, 0 }
  49   };
  50
  51 /* Implement TARGET_OPTION_INIT_STRUCT.  */
  52
  53 static void
  54 rs6000_option_init_struct (struct gcc_options *opts)
  55 {
  56   if (DEFAULT_ABI == ABI_DARWIN)
  57     /* The Darwin libraries never set errno, so we might as well
  58        avoid calling them when that's the only reason we would.  */
  59     opts->x_flag_errno_math = 0;
  60
  61   /* Enable section anchors by default.  */
  62   if (!TARGET_MACHO)
  63     opts->x_flag_section_anchors = 1;
  64
  65   /* By default, always emit DWARF-2 unwind info.  This allows debugging
  66      without maintaining a stack frame back-chain.  It also allows the
  67      debugger to find out where on-entry register values are stored at any
  68      point in a function, without having to analyze the executable code (which
  69      isn't even possible to do in the general case).  */
  70 #ifdef OBJECT_FORMAT_ELF
  71   opts->x_flag_asynchronous_unwind_tables = 1;
  72 #endif
  73 }
  74
  75 /* If not otherwise specified by a target, make 'long double' equivalent to
  76    'double'.  */
  77
  78 #ifndef RS6000_DEFAULT_LONG_DOUBLE_SIZE
  79 #define RS6000_DEFAULT_LONG_DOUBLE_SIZE 64
  80 #endif
  81
  82 /* Implement TARGET_HANDLE_OPTION.  */
  83
  84 static bool
  85 rs6000_handle_option (struct gcc_options *opts, struct gcc_options *opts_set,
  86                       const struct cl_decoded_option *decoded,
  87                       location_t loc)
  88 {
  89   char *p, *q;
  90   size_t code = decoded->opt_index;
  91   const char *arg = decoded->arg;
  92   int value = decoded->value;
  93
  94   switch (code)
  95     {
  96     case OPT_mfull_toc:
  97       opts->x_rs6000_isa_flags &= ~OPTION_MASK_MINIMAL_TOC;
  98       opts->x_TARGET_NO_FP_IN_TOC = 0;
  99       opts->x_TARGET_NO_SUM_IN_TOC = 0;
 100       opts_set->x_rs6000_isa_flags |= OPTION_MASK_MINIMAL_TOC;
 101 #ifdef TARGET_USES_SYSV4_OPT
 102       /* Note, V.4 no longer uses a normal TOC, so make -mfull-toc, be
 103          just the same as -mminimal-toc.  */
 104       opts->x_rs6000_isa_flags |= OPTION_MASK_MINIMAL_TOC;
 105       opts_set->x_rs6000_isa_flags |= OPTION_MASK_MINIMAL_TOC;
 106 #endif
 107       break;
 108
 109 #ifdef TARGET_USES_SYSV4_OPT
 110     case OPT_mtoc:
 111       /* Make -mtoc behave like -mminimal-toc.  */
 112       opts->x_rs6000_isa_flags |= OPTION_MASK_MINIMAL_TOC;
 113       opts_set->x_rs6000_isa_flags |= OPTION_MASK_MINIMAL_TOC;
 114       break;
 115 #endif
 116
 117 #ifdef TARGET_USES_AIX64_OPT
 118     case OPT_maix64:
 119 #else
 120     case OPT_m64:
 121 #endif
 122       opts->x_rs6000_isa_flags |= OPTION_MASK_POWERPC64;
 123       opts->x_rs6000_isa_flags |= (~opts_set->x_rs6000_isa_flags
 124                                    & OPTION_MASK_PPC_GFXOPT);
 125       opts_set->x_rs6000_isa_flags |= OPTION_MASK_POWERPC64;
 126       break;
 127
 128 #ifdef TARGET_USES_AIX64_OPT
 129     case OPT_maix32:
 130 #else
 131     case OPT_m32:
 132 #endif
 133       opts->x_rs6000_isa_flags &= ~OPTION_MASK_POWERPC64;
 134       opts_set->x_rs6000_isa_flags |= OPTION_MASK_POWERPC64;
 135       break;
 136
 137     case OPT_mminimal_toc:
 138       if (value == 1)
 139         {
 140           opts->x_TARGET_NO_FP_IN_TOC = 0;
 141           opts->x_TARGET_NO_SUM_IN_TOC = 0;
 142         }
 143       break;
 144
 145     case OPT_mpowerpc_gpopt:
 146     case OPT_mpowerpc_gfxopt:
 147       break;
 148
 149     case OPT_mdebug_:
 150       p = ASTRDUP (arg);
 151       opts->x_rs6000_debug = 0;
 152
 153       while ((q = strtok (p, ",")) != NULL)
 154         {
 155           unsigned mask = 0;
 156           bool invert;
 157
 158           p = NULL;
 159           if (*q == '!')
 160             {
 161               invert = true;
 162               q++;
 163             }
 164           else
 165             invert = false;
 166
 167           if (! strcmp (q, "all"))
 168             mask = MASK_DEBUG_ALL;
 169           else if (! strcmp (q, "stack"))
 170             mask = MASK_DEBUG_STACK;
 171           else if (! strcmp (q, "arg"))
 172             mask = MASK_DEBUG_ARG;
 173           else if (! strcmp (q, "reg"))
 174             mask = MASK_DEBUG_REG;
 175           else if (! strcmp (q, "addr"))
 176             mask = MASK_DEBUG_ADDR;
 177           else if (! strcmp (q, "cost"))
 178             mask = MASK_DEBUG_COST;
 179           else if (! strcmp (q, "target"))
 180             mask = MASK_DEBUG_TARGET;
 181           else if (! strcmp (q, "builtin"))
 182             mask = MASK_DEBUG_BUILTIN;
 183           else
 184             error_at (loc, "unknown %<-mdebug-%s%> switch", q);
 185
 186           if (invert)
 187             opts->x_rs6000_debug &= ~mask;
 188           else
 189             opts->x_rs6000_debug |= mask;
 190         }
 191       break;
 192
 193 #ifdef TARGET_USES_SYSV4_OPT
 194     case OPT_mrelocatable:
 195       if (value == 1)
 196         {
 197           opts->x_rs6000_isa_flags |= OPTION_MASK_MINIMAL_TOC;
 198           opts_set->x_rs6000_isa_flags |= OPTION_MASK_MINIMAL_TOC;
 199           opts->x_TARGET_NO_FP_IN_TOC = 1;
 200         }
 201       break;
 202
 203     case OPT_mrelocatable_lib:
 204       if (value == 1)
 205         {
 206           opts->x_rs6000_isa_flags |= (OPTION_MASK_RELOCATABLE
 207                                        | OPTION_MASK_MINIMAL_TOC);
 208           opts_set->x_rs6000_isa_flags |= (OPTION_MASK_RELOCATABLE
 209                                            | OPTION_MASK_MINIMAL_TOC);
 210           opts->x_TARGET_NO_FP_IN_TOC = 1;
 211         }
 212       else
 213         {
 214           opts->x_rs6000_isa_flags &= ~OPTION_MASK_RELOCATABLE;
 215           opts_set->x_rs6000_isa_flags |= OPTION_MASK_RELOCATABLE;
 216         }
 217       break;
 218 #endif
 219
 220     case OPT_mlong_double_:
 221       if (value != 64 && value != 128)
 222         {
 223           error_at (loc, "unknown switch %<-mlong-double-%s%>", arg);
 224           opts->x_rs6000_long_double_type_size
 225             = RS6000_DEFAULT_LONG_DOUBLE_SIZE;
 226           return false;
 227         }
 228       break;
 229
 230     case OPT_mrecip:
 231       opts->x_rs6000_recip_name = (value) ? "default" : "none";
 232       break;
 233     }
 234   return true;
 235 }
 236
 237 /* -fsplit-stack uses a field in the TCB, available with glibc-2.19.
 238    We also allow 2.18 because alignment padding guarantees that the
 239    space is available there too.  */
 240
 241 static bool
 242 rs6000_supports_split_stack (bool report,
 243                              struct gcc_options *opts ATTRIBUTE_UNUSED)
 244 {
 245 #ifndef TARGET_GLIBC_MAJOR
 246 #define TARGET_GLIBC_MAJOR 0
 247 #endif
 248 #ifndef TARGET_GLIBC_MINOR
 249 #define TARGET_GLIBC_MINOR 0
 250 #endif
 251   /* Note: Can't test DEFAULT_ABI here, it isn't set until later.  */
 252   if (TARGET_GLIBC_MAJOR * 1000 + TARGET_GLIBC_MINOR >= 2018
 253       && TARGET_64BIT
 254       && TARGET_ELF)
 255     return true;
 256
 257   if (report)
 258     error ("%<-fsplit-stack%> currently only supported on PowerPC64 GNU/Linux with glibc-2.18 or later");
 259   return false;
 260 }
 261
 262 #undef TARGET_HANDLE_OPTION
 263 #define TARGET_HANDLE_OPTION rs6000_handle_option
 264
 265 #undef TARGET_OPTION_INIT_STRUCT
 266 #define TARGET_OPTION_INIT_STRUCT rs6000_option_init_struct
 267
 268 #undef TARGET_OPTION_OPTIMIZATION_TABLE
 269 #define TARGET_OPTION_OPTIMIZATION_TABLE rs6000_option_optimization_table
 270
 271 #undef TARGET_SUPPORTS_SPLIT_STACK
 272 #define TARGET_SUPPORTS_SPLIT_STACK rs6000_supports_split_stack
 273
 274 struct gcc_targetm_common targetm_common = TARGETM_COMMON_INITIALIZER;