1 /* Common hooks for IBM RS/6000.
2 Copyright (C) 1991-2020 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
42 /* -frename-registers leads to non-optimal codegen and performance
43 on rs6000, turn it off by default. */
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
rs6000_option_init_struct(struct gcc_options * opts)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
rs6000_handle_option(struct gcc_options * opts,struct gcc_options * opts_set,const struct cl_decoded_option * decoded,location_t loc)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
rs6000_supports_split_stack(bool report,struct gcc_options * opts ATTRIBUTE_UNUSED)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;
275