xref: /netbsd-src/external/gpl3/gcc.old/dist/gcc/common/config/rs6000/rs6000-common.c (revision 867d70fc718005c0918b8b8b2f9d7f2d52d0a0db)
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 #include "params.h"
30 
31 /* Implement TARGET_OPTION_OPTIMIZATION_TABLE.  */
32 static const struct default_options rs6000_option_optimization_table[] =
33   {
34     /* Enable -fsched-pressure for first pass instruction scheduling.  */
35     { OPT_LEVELS_1_PLUS, OPT_fsched_pressure, NULL, 1 },
36     { OPT_LEVELS_NONE, 0, NULL, 0 }
37   };
38 
39 /* Implement TARGET_OPTION_INIT_STRUCT.  */
40 
41 static void
42 rs6000_option_init_struct (struct gcc_options *opts)
43 {
44   if (DEFAULT_ABI == ABI_DARWIN)
45     /* The Darwin libraries never set errno, so we might as well
46        avoid calling them when that's the only reason we would.  */
47     opts->x_flag_errno_math = 0;
48 
49   /* Enable section anchors by default.  */
50   if (!TARGET_MACHO)
51     opts->x_flag_section_anchors = 1;
52 
53   /* By default, always emit DWARF-2 unwind info.  This allows debugging
54      without maintaining a stack frame back-chain.  It also allows the
55      debugger to find out where on-entry register values are stored at any
56      point in a function, without having to analyze the executable code (which
57      isn't even possible to do in the general case).  */
58 #ifdef OBJECT_FORMAT_ELF
59   opts->x_flag_asynchronous_unwind_tables = 1;
60 #endif
61 }
62 
63 /* Implement TARGET_OPTION_DEFAULT_PARAMS.  */
64 
65 static void
66 rs6000_option_default_params (void)
67 {
68   /* Double growth factor to counter reduced min jump length.  */
69   set_default_param_value (PARAM_MAX_GROW_COPY_BB_INSNS, 16);
70 }
71 
72 /* If not otherwise specified by a target, make 'long double' equivalent to
73    'double'.  */
74 
75 #ifndef RS6000_DEFAULT_LONG_DOUBLE_SIZE
76 #define RS6000_DEFAULT_LONG_DOUBLE_SIZE 64
77 #endif
78 
79 /* Implement TARGET_HANDLE_OPTION.  */
80 
81 static bool
82 rs6000_handle_option (struct gcc_options *opts, struct gcc_options *opts_set,
83 		      const struct cl_decoded_option *decoded,
84 		      location_t loc)
85 {
86   char *p, *q;
87   size_t code = decoded->opt_index;
88   const char *arg = decoded->arg;
89   int value = decoded->value;
90 
91   switch (code)
92     {
93     case OPT_mfull_toc:
94       opts->x_rs6000_isa_flags &= ~OPTION_MASK_MINIMAL_TOC;
95       opts->x_TARGET_NO_FP_IN_TOC = 0;
96       opts->x_TARGET_NO_SUM_IN_TOC = 0;
97       opts_set->x_rs6000_isa_flags |= OPTION_MASK_MINIMAL_TOC;
98 #ifdef TARGET_USES_SYSV4_OPT
99       /* Note, V.4 no longer uses a normal TOC, so make -mfull-toc, be
100 	 just the same as -mminimal-toc.  */
101       opts->x_rs6000_isa_flags |= OPTION_MASK_MINIMAL_TOC;
102       opts_set->x_rs6000_isa_flags |= OPTION_MASK_MINIMAL_TOC;
103 #endif
104       break;
105 
106 #ifdef TARGET_USES_SYSV4_OPT
107     case OPT_mtoc:
108       /* Make -mtoc behave like -mminimal-toc.  */
109       opts->x_rs6000_isa_flags |= OPTION_MASK_MINIMAL_TOC;
110       opts_set->x_rs6000_isa_flags |= OPTION_MASK_MINIMAL_TOC;
111       break;
112 #endif
113 
114 #ifdef TARGET_USES_AIX64_OPT
115     case OPT_maix64:
116 #else
117     case OPT_m64:
118 #endif
119       opts->x_rs6000_isa_flags |= OPTION_MASK_POWERPC64;
120       opts->x_rs6000_isa_flags |= (~opts_set->x_rs6000_isa_flags
121 				   & OPTION_MASK_PPC_GFXOPT);
122       opts_set->x_rs6000_isa_flags |= OPTION_MASK_POWERPC64;
123       break;
124 
125 #ifdef TARGET_USES_AIX64_OPT
126     case OPT_maix32:
127 #else
128     case OPT_m32:
129 #endif
130       opts->x_rs6000_isa_flags &= ~OPTION_MASK_POWERPC64;
131       opts_set->x_rs6000_isa_flags |= OPTION_MASK_POWERPC64;
132       break;
133 
134     case OPT_mminimal_toc:
135       if (value == 1)
136 	{
137 	  opts->x_TARGET_NO_FP_IN_TOC = 0;
138 	  opts->x_TARGET_NO_SUM_IN_TOC = 0;
139 	}
140       break;
141 
142     case OPT_mpowerpc_gpopt:
143     case OPT_mpowerpc_gfxopt:
144       break;
145 
146     case OPT_mdebug_:
147       p = ASTRDUP (arg);
148       opts->x_rs6000_debug = 0;
149 
150       while ((q = strtok (p, ",")) != NULL)
151 	{
152 	  unsigned mask = 0;
153 	  bool invert;
154 
155 	  p = NULL;
156 	  if (*q == '!')
157 	    {
158 	      invert = true;
159 	      q++;
160 	    }
161 	  else
162 	    invert = false;
163 
164 	  if (! strcmp (q, "all"))
165 	    mask = MASK_DEBUG_ALL;
166 	  else if (! strcmp (q, "stack"))
167 	    mask = MASK_DEBUG_STACK;
168 	  else if (! strcmp (q, "arg"))
169 	    mask = MASK_DEBUG_ARG;
170 	  else if (! strcmp (q, "reg"))
171 	    mask = MASK_DEBUG_REG;
172 	  else if (! strcmp (q, "addr"))
173 	    mask = MASK_DEBUG_ADDR;
174 	  else if (! strcmp (q, "cost"))
175 	    mask = MASK_DEBUG_COST;
176 	  else if (! strcmp (q, "target"))
177 	    mask = MASK_DEBUG_TARGET;
178 	  else if (! strcmp (q, "builtin"))
179 	    mask = MASK_DEBUG_BUILTIN;
180 	  else
181 	    error_at (loc, "unknown %<-mdebug-%s%> switch", q);
182 
183 	  if (invert)
184 	    opts->x_rs6000_debug &= ~mask;
185 	  else
186 	    opts->x_rs6000_debug |= mask;
187 	}
188       break;
189 
190 #ifdef TARGET_USES_SYSV4_OPT
191     case OPT_mrelocatable:
192       if (value == 1)
193 	{
194 	  opts->x_rs6000_isa_flags |= OPTION_MASK_MINIMAL_TOC;
195 	  opts_set->x_rs6000_isa_flags |= OPTION_MASK_MINIMAL_TOC;
196 	  opts->x_TARGET_NO_FP_IN_TOC = 1;
197 	}
198       break;
199 
200     case OPT_mrelocatable_lib:
201       if (value == 1)
202 	{
203 	  opts->x_rs6000_isa_flags |= (OPTION_MASK_RELOCATABLE
204 				       | OPTION_MASK_MINIMAL_TOC);
205 	  opts_set->x_rs6000_isa_flags |= (OPTION_MASK_RELOCATABLE
206 					   | OPTION_MASK_MINIMAL_TOC);
207 	  opts->x_TARGET_NO_FP_IN_TOC = 1;
208 	}
209       else
210 	{
211 	  opts->x_rs6000_isa_flags &= ~OPTION_MASK_RELOCATABLE;
212 	  opts_set->x_rs6000_isa_flags |= OPTION_MASK_RELOCATABLE;
213 	}
214       break;
215 #endif
216 
217     case OPT_mlong_double_:
218       if (value != 64 && value != 128)
219 	{
220 	  error_at (loc, "unknown switch %<-mlong-double-%s%>", arg);
221 	  opts->x_rs6000_long_double_type_size
222 	    = RS6000_DEFAULT_LONG_DOUBLE_SIZE;
223 	  return false;
224 	}
225       break;
226 
227     case OPT_mrecip:
228       opts->x_rs6000_recip_name = (value) ? "default" : "none";
229       break;
230     }
231   return true;
232 }
233 
234 /* -fsplit-stack uses a field in the TCB, available with glibc-2.19.
235    We also allow 2.18 because alignment padding guarantees that the
236    space is available there too.  */
237 
238 static bool
239 rs6000_supports_split_stack (bool report,
240 			     struct gcc_options *opts ATTRIBUTE_UNUSED)
241 {
242 #ifndef TARGET_GLIBC_MAJOR
243 #define TARGET_GLIBC_MAJOR 0
244 #endif
245 #ifndef TARGET_GLIBC_MINOR
246 #define TARGET_GLIBC_MINOR 0
247 #endif
248   /* Note: Can't test DEFAULT_ABI here, it isn't set until later.  */
249   if (TARGET_GLIBC_MAJOR * 1000 + TARGET_GLIBC_MINOR >= 2018
250       && TARGET_64BIT
251       && TARGET_ELF)
252     return true;
253 
254   if (report)
255     error ("%<-fsplit-stack%> currently only supported on PowerPC64 GNU/Linux with glibc-2.18 or later");
256   return false;
257 }
258 
259 #undef TARGET_HANDLE_OPTION
260 #define TARGET_HANDLE_OPTION rs6000_handle_option
261 
262 #undef TARGET_OPTION_INIT_STRUCT
263 #define TARGET_OPTION_INIT_STRUCT rs6000_option_init_struct
264 
265 #undef TARGET_OPTION_DEFAULT_PARAMS
266 #define TARGET_OPTION_DEFAULT_PARAMS rs6000_option_default_params
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;
275