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     { OPT_LEVELS_NONE, 0, NULL, 0 }
  46   };
  47
  48 /* Implement TARGET_OPTION_INIT_STRUCT.  */
  49
  50 static void
  51 rs6000_option_init_struct (struct gcc_options *opts)
  52 {
  53   if (DEFAULT_ABI == ABI_DARWIN)
  54     /* The Darwin libraries never set errno, so we might as well
  55        avoid calling them when that's the only reason we would.  */
  56     opts->x_flag_errno_math = 0;
  57
  58   /* Enable section anchors by default.  */
  59   if (!TARGET_MACHO)
  60     opts->x_flag_section_anchors = 1;
  61
  62   /* By default, always emit DWARF-2 unwind info.  This allows debugging
  63      without maintaining a stack frame back-chain.  It also allows the
  64      debugger to find out where on-entry register values are stored at any
  65      point in a function, without having to analyze the executable code (which
  66      isn't even possible to do in the general case).  */
  67 #ifdef OBJECT_FORMAT_ELF
  68   opts->x_flag_asynchronous_unwind_tables = 1;
  69 #endif
  70 }
  71
  72 /* Implement TARGET_OPTION_DEFAULT_PARAMS.  */
  73
  74 static void
  75 rs6000_option_default_params (void)
  76 {
  77   /* Double growth factor to counter reduced min jump length.  */
  78   param_max_grow_copy_bb_insns = 16;
  79 }
  80
  81 /* If not otherwise specified by a target, make 'long double' equivalent to
  82    'double'.  */
  83
  84 #ifndef RS6000_DEFAULT_LONG_DOUBLE_SIZE
  85 #define RS6000_DEFAULT_LONG_DOUBLE_SIZE 64
  86 #endif
  87
  88 /* Implement TARGET_HANDLE_OPTION.  */
  89
  90 static bool
  91 rs6000_handle_option (struct gcc_options *opts, struct gcc_options *opts_set,
  92                       const struct cl_decoded_option *decoded,
  93                       location_t loc)
  94 {
  95   char *p, *q;
  96   size_t code = decoded->opt_index;
  97   const char *arg = decoded->arg;
  98   int value = decoded->value;
  99
 100   switch (code)
 101     {
 102     case OPT_mfull_toc:
 103       opts->x_rs6000_isa_flags &= ~OPTION_MASK_MINIMAL_TOC;
 104       opts->x_TARGET_NO_FP_IN_TOC = 0;
 105       opts->x_TARGET_NO_SUM_IN_TOC = 0;
 106       opts_set->x_rs6000_isa_flags |= OPTION_MASK_MINIMAL_TOC;
 107 #ifdef TARGET_USES_SYSV4_OPT
 108       /* Note, V.4 no longer uses a normal TOC, so make -mfull-toc, be
 109          just the same as -mminimal-toc.  */
 110       opts->x_rs6000_isa_flags |= OPTION_MASK_MINIMAL_TOC;
 111       opts_set->x_rs6000_isa_flags |= OPTION_MASK_MINIMAL_TOC;
 112 #endif
 113       break;
 114
 115 #ifdef TARGET_USES_SYSV4_OPT
 116     case OPT_mtoc:
 117       /* Make -mtoc behave like -mminimal-toc.  */
 118       opts->x_rs6000_isa_flags |= OPTION_MASK_MINIMAL_TOC;
 119       opts_set->x_rs6000_isa_flags |= OPTION_MASK_MINIMAL_TOC;
 120       break;
 121 #endif
 122
 123 #ifdef TARGET_USES_AIX64_OPT
 124     case OPT_maix64:
 125 #else
 126     case OPT_m64:
 127 #endif
 128       opts->x_rs6000_isa_flags |= OPTION_MASK_POWERPC64;
 129       opts->x_rs6000_isa_flags |= (~opts_set->x_rs6000_isa_flags
 130                                    & OPTION_MASK_PPC_GFXOPT);
 131       opts_set->x_rs6000_isa_flags |= OPTION_MASK_POWERPC64;
 132       break;
 133
 134 #ifdef TARGET_USES_AIX64_OPT
 135     case OPT_maix32:
 136 #else
 137     case OPT_m32:
 138 #endif
 139       opts->x_rs6000_isa_flags &= ~OPTION_MASK_POWERPC64;
 140       opts_set->x_rs6000_isa_flags |= OPTION_MASK_POWERPC64;
 141       break;
 142
 143     case OPT_mminimal_toc:
 144       if (value == 1)
 145         {
 146           opts->x_TARGET_NO_FP_IN_TOC = 0;
 147           opts->x_TARGET_NO_SUM_IN_TOC = 0;
 148         }
 149       break;
 150
 151     case OPT_mpowerpc_gpopt:
 152     case OPT_mpowerpc_gfxopt:
 153       break;
 154
 155     case OPT_mdebug_:
 156       p = ASTRDUP (arg);
 157       opts->x_rs6000_debug = 0;
 158
 159       while ((q = strtok (p, ",")) != NULL)
 160         {
 161           unsigned mask = 0;
 162           bool invert;
 163
 164           p = NULL;
 165           if (*q == '!')
 166             {
 167               invert = true;
 168               q++;
 169             }
 170           else
 171             invert = false;
 172
 173           if (! strcmp (q, "all"))
 174             mask = MASK_DEBUG_ALL;
 175           else if (! strcmp (q, "stack"))
 176             mask = MASK_DEBUG_STACK;
 177           else if (! strcmp (q, "arg"))
 178             mask = MASK_DEBUG_ARG;
 179           else if (! strcmp (q, "reg"))
 180             mask = MASK_DEBUG_REG;
 181           else if (! strcmp (q, "addr"))
 182             mask = MASK_DEBUG_ADDR;
 183           else if (! strcmp (q, "cost"))
 184             mask = MASK_DEBUG_COST;
 185           else if (! strcmp (q, "target"))
 186             mask = MASK_DEBUG_TARGET;
 187           else if (! strcmp (q, "builtin"))
 188             mask = MASK_DEBUG_BUILTIN;
 189           else
 190             error_at (loc, "unknown %<-mdebug-%s%> switch", q);
 191
 192           if (invert)
 193             opts->x_rs6000_debug &= ~mask;
 194           else
 195             opts->x_rs6000_debug |= mask;
 196         }
 197       break;
 198
 199 #ifdef TARGET_USES_SYSV4_OPT
 200     case OPT_mrelocatable:
 201       if (value == 1)
 202         {
 203           opts->x_rs6000_isa_flags |= OPTION_MASK_MINIMAL_TOC;
 204           opts_set->x_rs6000_isa_flags |= OPTION_MASK_MINIMAL_TOC;
 205           opts->x_TARGET_NO_FP_IN_TOC = 1;
 206         }
 207       break;
 208
 209     case OPT_mrelocatable_lib:
 210       if (value == 1)
 211         {
 212           opts->x_rs6000_isa_flags |= (OPTION_MASK_RELOCATABLE
 213                                        | OPTION_MASK_MINIMAL_TOC);
 214           opts_set->x_rs6000_isa_flags |= (OPTION_MASK_RELOCATABLE
 215                                            | OPTION_MASK_MINIMAL_TOC);
 216           opts->x_TARGET_NO_FP_IN_TOC = 1;
 217         }
 218       else
 219         {
 220           opts->x_rs6000_isa_flags &= ~OPTION_MASK_RELOCATABLE;
 221           opts_set->x_rs6000_isa_flags |= OPTION_MASK_RELOCATABLE;
 222         }
 223       break;
 224 #endif
 225
 226     case OPT_mlong_double_:
 227       if (value != 64 && value != 128)
 228         {
 229           error_at (loc, "unknown switch %<-mlong-double-%s%>", arg);
 230           opts->x_rs6000_long_double_type_size
 231             = RS6000_DEFAULT_LONG_DOUBLE_SIZE;
 232           return false;
 233         }
 234       break;
 235
 236     case OPT_mrecip:
 237       opts->x_rs6000_recip_name = (value) ? "default" : "none";
 238       break;
 239     }
 240   return true;
 241 }
 242
 243 /* -fsplit-stack uses a field in the TCB, available with glibc-2.19.
 244    We also allow 2.18 because alignment padding guarantees that the
 245    space is available there too.  */
 246
 247 static bool
 248 rs6000_supports_split_stack (bool report,
 249                              struct gcc_options *opts ATTRIBUTE_UNUSED)
 250 {
 251 #ifndef TARGET_GLIBC_MAJOR
 252 #define TARGET_GLIBC_MAJOR 0
 253 #endif
 254 #ifndef TARGET_GLIBC_MINOR
 255 #define TARGET_GLIBC_MINOR 0
 256 #endif
 257   /* Note: Can't test DEFAULT_ABI here, it isn't set until later.  */
 258   if (TARGET_GLIBC_MAJOR * 1000 + TARGET_GLIBC_MINOR >= 2018
 259       && TARGET_64BIT
 260       && TARGET_ELF)
 261     return true;
 262
 263   if (report)
 264     error ("%<-fsplit-stack%> currently only supported on PowerPC64 GNU/Linux with glibc-2.18 or later");
 265   return false;
 266 }
 267
 268 #undef TARGET_HANDLE_OPTION
 269 #define TARGET_HANDLE_OPTION rs6000_handle_option
 270
 271 #undef TARGET_OPTION_INIT_STRUCT
 272 #define TARGET_OPTION_INIT_STRUCT rs6000_option_init_struct
 273
 274 #undef TARGET_OPTION_DEFAULT_PARAMS
 275 #define TARGET_OPTION_DEFAULT_PARAMS rs6000_option_default_params
 276
 277 #undef TARGET_OPTION_OPTIMIZATION_TABLE
 278 #define TARGET_OPTION_OPTIMIZATION_TABLE rs6000_option_optimization_table
 279
 280 #undef TARGET_SUPPORTS_SPLIT_STACK
 281 #define TARGET_SUPPORTS_SPLIT_STACK rs6000_supports_split_stack
 282
 283 struct gcc_targetm_common targetm_common = TARGETM_COMMON_INITIALIZER;