xref: /netbsd-src/external/gpl3/gcc/dist/gcc/common/config/avr/avr-common.cc (revision b1e838363e3c6fc78a55519254d99869742dd33c)
1 /* Common hooks for ATMEL AVR.
2    Copyright (C) 1998-2022 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
7    it under the terms of the GNU General Public License as published by
8    the Free Software Foundation; either version 3, or (at your option)
9    any later version.
10 
11    GCC is distributed in the hope that it will be useful,
12    but WITHOUT ANY WARRANTY; without even the implied warranty of
13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14    GNU General Public 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 "tm.h"
24 #include "common/common-target.h"
25 #include "common/common-target-def.h"
26 #include "opts.h"
27 #include "diagnostic.h"
28 
29 /* Implement TARGET_OPTION_OPTIMIZATION_TABLE.  */
30 static const struct default_options avr_option_optimization_table[] =
31   {
32     // With -fdelete-null-pointer-checks option, the compiler assumes
33     // that dereferencing of a null pointer would halt the program.
34     // For AVR this assumption is not true and a program can safely
35     // dereference null pointers.  Changes made by this option may not
36     // work properly for AVR.  So disable this option.
37     { OPT_LEVELS_ALL, OPT_fdelete_null_pointer_checks, NULL, 0 },
38     // The only effect of -fcaller-saves might be that it triggers
39     // a frame without need when it tries to be smart around calls.
40     { OPT_LEVELS_ALL, OPT_fcaller_saves, NULL, 0 },
41     { OPT_LEVELS_1_PLUS_NOT_DEBUG, OPT_mgas_isr_prologues, NULL, 1 },
42     { OPT_LEVELS_1_PLUS, OPT_mmain_is_OS_task, NULL, 1 },
43     // Stick to the "old" placement of the subreg lowering pass.
44     { OPT_LEVELS_1_PLUS, OPT_fsplit_wide_types_early, NULL, 1 },
45     /* Allow optimizer to introduce store data races. This used to be the
46        default -- it was changed because bigger targets did not see any
47        performance decrease. For the AVR though, disallowing data races
48        introduces additional code in LIM and increases reg pressure.  */
49     { OPT_LEVELS_ALL, OPT_fallow_store_data_races, NULL, 1 },
50 
51 #if defined (WITH_DOUBLE64)
52     { OPT_LEVELS_ALL, OPT_mdouble_, NULL, 64 },
53 #elif defined (WITH_DOUBLE32)
54     { OPT_LEVELS_ALL, OPT_mdouble_, NULL, 32 },
55 #else
56 #error "align this with config.gcc"
57 #endif
58 
59 #if defined (WITH_LONG_DOUBLE64)
60     { OPT_LEVELS_ALL, OPT_mlong_double_, NULL, 64 },
61 #elif defined (WITH_LONG_DOUBLE32)
62     { OPT_LEVELS_ALL, OPT_mlong_double_, NULL, 32 },
63 #else
64 #error "align this with config.gcc"
65 #endif
66 
67     { OPT_LEVELS_NONE, 0, NULL, 0 }
68   };
69 
70 
71 /* Implement `TARGET_HANDLE_OPTION'.  */
72 
73 /* This is the same logic that driver-avr.cc:avr_double_lib() applies
74    during DRIVER_SELF_SPECS, but this time we complain about -mdouble=
75    and -mlong-double= that are not provided by --with-double= resp.
76    --with-long-double=  */
77 
78 static bool
avr_handle_option(struct gcc_options * opts,struct gcc_options *,const struct cl_decoded_option * decoded,location_t loc ATTRIBUTE_UNUSED)79 avr_handle_option (struct gcc_options *opts, struct gcc_options*,
80                    const struct cl_decoded_option *decoded,
81                    location_t loc ATTRIBUTE_UNUSED)
82 {
83   int value = decoded->value;
84 
85   switch (decoded->opt_index)
86     {
87     case OPT_mdouble_:
88       if (value == 64)
89         {
90 #if !defined (HAVE_DOUBLE64)
91           error_at (loc, "option %<-mdouble=64%> is only available if "
92                     "configured %<--with-double={64|64,32|32,64}%>");
93 #endif
94           opts->x_avr_long_double = 64;
95         }
96       else if (value == 32)
97         {
98 #if !defined (HAVE_DOUBLE32)
99           error_at (loc, "option %<-mdouble=32%> is only available if "
100                     "configured %<--with-double={32|32,64|64,32}%>");
101 #endif
102         }
103       else
104         gcc_unreachable();
105 
106 #if defined (HAVE_LONG_DOUBLE_IS_DOUBLE)
107       opts->x_avr_long_double = value;
108 #endif
109       break; // -mdouble=
110 
111     case OPT_mlong_double_:
112       if (value == 64)
113         {
114 #if !defined (HAVE_LONG_DOUBLE64)
115           error_at (loc, "option %<-mlong-double=64%> is only available if "
116                     "configured %<--with-long-double={64|64,32|32,64}%>, "
117                     "or %<--with-long-double=double%> together with "
118                     "%<--with-double={64|64,32|32,64}%>");
119 #endif
120         }
121       else if (value == 32)
122         {
123 #if !defined (HAVE_LONG_DOUBLE32)
124           error_at (loc, "option %<-mlong-double=32%> is only available if "
125                     "configured %<--with-long-double={32|32,64|64,32}%>, "
126                     "or %<--with-long-double=double%> together with "
127                     "%<--with-double={32|32,64|64,32}%>");
128 #endif
129           opts->x_avr_double = 32;
130         }
131       else
132         gcc_unreachable();
133 
134 #if defined (HAVE_LONG_DOUBLE_IS_DOUBLE)
135       opts->x_avr_double = value;
136 #endif
137       break; // -mlong-double=
138     }
139 
140   return true;
141 }
142 
143 
144 #undef TARGET_HANDLE_OPTION
145 #define TARGET_HANDLE_OPTION avr_handle_option
146 
147 #undef TARGET_OPTION_OPTIMIZATION_TABLE
148 #define TARGET_OPTION_OPTIMIZATION_TABLE avr_option_optimization_table
149 
150 #undef TARGET_EXCEPT_UNWIND_INFO
151 #define TARGET_EXCEPT_UNWIND_INFO sjlj_except_unwind_info
152 
153 struct gcc_targetm_common targetm_common = TARGETM_COMMON_INITIALIZER;
154