1 /* Target definitions for GNU compiler for mc680x0 running System V.4 2 Copyright (C) 1991, 1993, 1994, 1995, 1996, 1998, 1999, 2000 3 Free Software Foundation, Inc. 4 Contributed by Ron Guilmette (rfg@monkeys.com) and 5 Fred Fish (fnf@cygnus.com). 6 7 This file is part of GNU CC. 8 9 GNU CC is free software; you can redistribute it and/or modify 10 it under the terms of the GNU General Public License as published by 11 the Free Software Foundation; either version 2, or (at your option) 12 any later version. 13 14 GNU CC is distributed in the hope that it will be useful, 15 but WITHOUT ANY WARRANTY; without even the implied warranty of 16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 17 GNU General Public License for more details. 18 19 You should have received a copy of the GNU General Public License 20 along with GNU CC; see the file COPYING. If not, write to 21 the Free Software Foundation, 59 Temple Place - Suite 330, 22 Boston, MA 02111-1307, USA. */ 23 24 /* Use SGS_* macros to control compilation in m68k.md */ 25 26 #define SGS_SWITCH_TABLES /* Different switch table handling */ 27 28 /* TODO: convert includes to ${tm_file} list in config.gcc. */ 29 #include "m68k/sgs.h" /* The m68k/SVR4 assembler is SGS based */ 30 31 #include "dbxelf.h" 32 #include "elfos.h" 33 #include "svr4.h" /* Pick up the generic SVR4 macros */ 34 35 /* See m68k.h. 7 means 68020 with 68881. */ 36 37 #ifndef TARGET_DEFAULT 38 #define TARGET_DEFAULT (MASK_BITFIELD|MASK_68881|MASK_68020) 39 #endif 40 41 /* Override the definition of NO_DOLLAR_IN_LABEL in svr4.h, for special 42 g++ assembler names. When this is defined, g++ uses embedded '.' 43 characters and some m68k assemblers have problems with this. The 44 chances are much greater that any particular assembler will permit 45 embedded '$' characters. */ 46 47 #undef NO_DOLLAR_IN_LABEL 48 49 /* Define PCC_STATIC_STRUCT_RETURN if the convention on the target machine 50 is to use the nonreentrant technique for returning structure and union 51 values, as commonly implemented by the AT&T Portable C Compiler (PCC). 52 When defined, the gcc option -fpcc-struct-return can be used to cause 53 this form to be generated. When undefined, the option does nothing. 54 For m68k SVR4, the convention is to use a reentrant technique compatible 55 with the gcc default, so override the definition of this macro in m68k.h */ 56 57 #undef PCC_STATIC_STRUCT_RETURN 58 59 /* Provide a set of pre-definitions and pre-assertions appropriate for 60 the m68k running svr4. __svr4__ is our extension. */ 61 62 #define CPP_PREDEFINES \ 63 "-Dm68k -Dunix -D__svr4__ -D__motorola__ \ 64 -Asystem=unix -Asystem=svr4 -Acpu=m68k -Amachine=m68k" 65 66 /* Test to see if the target includes a 68881 by default, and use CPP_SPEC 67 to control whether or not __HAVE_68881__ is defined by default or not. 68 If a 68881 is the default, gcc will use inline 68881 instructions, by 69 predefining __HAVE_68881__, unless -msoft-float is specified. 70 If a 68881 is not the default, gcc will only define __HAVE_68881__ if 71 -m68881 is specified. */ 72 73 #if TARGET_DEFAULT & MASK_68881 74 #define CPP_SPEC "%{!msoft-float:-D__HAVE_68881__}" 75 #else 76 #define CPP_SPEC "%{m68881:-D__HAVE_68881__}" 77 #endif 78 79 /* Output assembler code to FILE to increment profiler label # LABELNO 80 for profiling a function entry. We override the definition in m68k.h 81 and match the way the native m68k/SVR4 compiler does profiling, with the 82 address of the profile counter in a1, not a0, and using bsr rather 83 than jsr. */ 84 85 #undef FUNCTION_PROFILER 86 #define FUNCTION_PROFILER(FILE, LABELNO) \ 87 asm_fprintf ((FILE), "\tlea.l\t(%LLP%d,%Rpc),%Ra1\n\tbsr\t_mcount\n", \ 88 (LABELNO)) 89 90 /* Local common symbols are declared to the assembler with ".lcomm" rather 91 than ".bss", so override the definition in svr4.h */ 92 /* ??? svr4.h no longer defines this, and this is only used by m68k/amix.h. */ 93 94 #undef BSS_ASM_OP 95 #define BSS_ASM_OP "\t.lcomm\t" 96 97 /* Register in which address to store a structure value is passed to a 98 function. The default in m68k.h is a1. For m68k/SVR4 it is a0. */ 99 100 #undef STRUCT_VALUE_REGNUM 101 #define STRUCT_VALUE_REGNUM 8 102 103 /* Register in which static-chain is passed to a function. The 104 default in m68k.h is a0, but that is already the struct value 105 regnum. Make it a1 instead. */ 106 107 #undef STATIC_CHAIN_REGNUM 108 #define STATIC_CHAIN_REGNUM 9 109 110 #define ASM_COMMENT_START "#" 111 112 /* Define how the m68k registers should be numbered for Dwarf output. 113 The numbering provided here should be compatible with the native 114 SVR4 SDB debugger in the m68k/SVR4 reference port, where d0-d7 115 are 0-7, a0-a8 are 8-15, and fp0-fp7 are 16-23. */ 116 117 #define DBX_REGISTER_NUMBER(REGNO) (REGNO) 118 119 /* The ASM_OUTPUT_SKIP macro is first defined in m68k.h, using ".skip". 120 It is then overridden by m68k/sgs.h to use ".space", and again by svr4.h 121 to use ".zero". The m68k/SVR4 assembler uses ".space", so repeat the 122 definition from m68k/sgs.h here. Note that ASM_NO_SKIP_IN_TEXT is 123 defined in m68k/sgs.h, so we don't have to repeat it here. */ 124 125 #undef ASM_OUTPUT_SKIP 126 #define ASM_OUTPUT_SKIP(FILE,SIZE) \ 127 fprintf (FILE, "%s%u\n", SPACE_ASM_OP, (SIZE)) 128 129 /* 1 if N is a possible register number for a function value. 130 For m68k/SVR4 allow d0, a0, or fp0 as return registers, for integral, 131 pointer, or floating types, respectively. Reject fp0 if not using a 132 68881 coprocessor. */ 133 134 #undef FUNCTION_VALUE_REGNO_P 135 #define FUNCTION_VALUE_REGNO_P(N) \ 136 ((N) == 0 || (N) == 8 || (TARGET_68881 && (N) == 16)) 137 138 /* Define this to be true when FUNCTION_VALUE_REGNO_P is true for 139 more than one register. */ 140 141 #undef NEEDS_UNTYPED_CALL 142 #define NEEDS_UNTYPED_CALL 1 143 144 /* Define how to generate (in the callee) the output value of a function 145 and how to find (in the caller) the value returned by a function. VALTYPE 146 is the data type of the value (as a tree). If the precise function being 147 called is known, FUNC is its FUNCTION_DECL; otherwise, FUNC is 0. 148 For m68k/SVR4 generate the result in d0, a0, or fp0 as appropriate. */ 149 150 #undef FUNCTION_VALUE 151 #define FUNCTION_VALUE(VALTYPE, FUNC) \ 152 (TREE_CODE (VALTYPE) == REAL_TYPE && TARGET_68881 \ 153 ? gen_rtx_REG (TYPE_MODE (VALTYPE), 16) \ 154 : (POINTER_TYPE_P (VALTYPE) \ 155 ? gen_rtx_REG (TYPE_MODE (VALTYPE), 8) \ 156 : gen_rtx_REG (TYPE_MODE (VALTYPE), 0))) 157 158 /* For compatibility with the large body of existing code which does not 159 always properly declare external functions returning pointer types, the 160 m68k/SVR4 convention is to copy the value returned for pointer functions 161 from a0 to d0 in the function epilogue, so that callers that have 162 neglected to properly declare the callee can still find the correct return 163 value. */ 164 165 #define FUNCTION_EXTRA_EPILOGUE(FILE, SIZE) \ 166 do { \ 167 if (current_function_returns_pointer \ 168 && ! find_equiv_reg (0, get_last_insn (), 0, 0, 0, 8, Pmode)) \ 169 asm_fprintf (FILE, "\tmov.l %Ra0,%Rd0\n"); \ 170 } while (0); 171 172 /* Define how to find the value returned by a library function assuming the 173 value has mode MODE. 174 For m68k/SVR4 look for integer values in d0, pointer values in d0 175 (returned in both d0 and a0), and floating values in fp0. */ 176 177 #undef LIBCALL_VALUE 178 #define LIBCALL_VALUE(MODE) \ 179 ((((MODE) == SFmode || (MODE) == DFmode || (MODE) == XFmode) \ 180 && TARGET_68881) \ 181 ? gen_rtx_REG ((MODE), 16) \ 182 : gen_rtx_REG ((MODE), 0)) 183 184 /* Boundary (in *bits*) on which stack pointer should be aligned. 185 The m68k/SVR4 convention is to keep the stack pointer longword aligned. */ 186 187 #undef STACK_BOUNDARY 188 #define STACK_BOUNDARY 32 189 190 /* Alignment of field after `int : 0' in a structure. 191 For m68k/SVR4, this is the next longword boundary. */ 192 193 #undef EMPTY_FIELD_BOUNDARY 194 #define EMPTY_FIELD_BOUNDARY 32 195 196 /* No data type wants to be aligned rounder than this. 197 For m68k/SVR4, some types (doubles for example) are aligned on 8 byte 198 boundaries */ 199 200 #undef BIGGEST_ALIGNMENT 201 #define BIGGEST_ALIGNMENT 64 202 203 /* SVR4 m68k assembler is bitching on the `comm i,1,1' which asks for 204 1 byte alignment. Don't generate alignment for COMMON seems to be 205 safer until we the assembler is fixed. */ 206 #undef ASM_OUTPUT_ALIGNED_COMMON 207 /* Same problem with this one. */ 208 #undef ASM_OUTPUT_ALIGNED_LOCAL 209 210 /* The `string' directive on m68k svr4 does not handle string with 211 escape char (ie., `\') right. Use normal way to output ASCII bytes 212 seems to be safer. */ 213 #undef ASM_OUTPUT_ASCII 214 #define ASM_OUTPUT_ASCII(FILE,PTR,LEN) \ 215 do { \ 216 register size_t sp = 0, limit = (LEN); \ 217 fputs (integer_asm_op (1, TRUE), (FILE)); \ 218 do { \ 219 int ch = (PTR)[sp]; \ 220 if (ch > ' ' && ! (ch & 0x80) && ch != '\\') \ 221 { \ 222 fprintf ((FILE), "'%c", ch); \ 223 } \ 224 else \ 225 { \ 226 fprintf ((FILE), "0x%x", ch); \ 227 } \ 228 if (++sp < limit) \ 229 { \ 230 if ((sp % 10) == 0) \ 231 { \ 232 fprintf ((FILE), "\n%s", integer_asm_op (1, TRUE)); \ 233 } \ 234 else \ 235 { \ 236 putc (',', (FILE)); \ 237 } \ 238 } \ 239 } while (sp < limit); \ 240 putc ('\n', (FILE)); \ 241 } while (0) 242 243 /* SVR4 m68k assembler is bitching on the syntax `2.b'. 244 So use the "LLDnnn-LLnnn" format. Define LLDnnn after the table. */ 245 246 #undef ASM_OUTPUT_CASE_END 247 #define ASM_OUTPUT_CASE_END(FILE,NUM,TABLE) \ 248 do { \ 249 if (switch_table_difference_label_flag) \ 250 asm_fprintf ((FILE), "%s%LLD%d,%LL%d\n", SET_ASM_OP, (NUM), (NUM)); \ 251 switch_table_difference_label_flag = 0; \ 252 } while (0) 253 254 int switch_table_difference_label_flag; 255 256 #undef ASM_OUTPUT_COMMON 257 #undef ASM_OUTPUT_LOCAL 258 #define ASM_OUTPUT_COMMON(FILE, NAME, SIZE, ROUNDED) \ 259 ( fputs (".comm ", (FILE)), \ 260 assemble_name ((FILE), (NAME)), \ 261 fprintf ((FILE), ",%u\n", (SIZE))) 262 263 #define ASM_OUTPUT_LOCAL(FILE, NAME, SIZE, ROUNDED) \ 264 ( fputs (".lcomm ", (FILE)), \ 265 assemble_name ((FILE), (NAME)), \ 266 fprintf ((FILE), ",%u\n", (SIZE))) 267 268 /* Override the definition in svr4.h. In m68k svr4, using swbeg is the 269 standard way to do switch table. */ 270 #undef ASM_OUTPUT_BEFORE_CASE_LABEL 271 #define ASM_OUTPUT_BEFORE_CASE_LABEL(FILE,PREFIX,NUM,TABLE) \ 272 fprintf ((FILE), "%s&%d\n", SWBEG_ASM_OP, XVECLEN (PATTERN (TABLE), 1)); 273 274 /* Output assembler code for a block containing the constant parts 275 of a trampoline, leaving space for the variable parts. */ 276 277 /* On m68k svr4, the trampoline is different from the generic version 278 in that we use a1 as the static call chain. */ 279 280 #undef TRAMPOLINE_TEMPLATE 281 #define TRAMPOLINE_TEMPLATE(FILE) \ 282 { \ 283 assemble_aligned_integer (2, GEN_INT (0x227a)); \ 284 assemble_aligned_integer (2, GEN_INT (8)); \ 285 assemble_aligned_integer (2, GEN_INT (0x2f3a)); \ 286 assemble_aligned_integer (2, GEN_INT (8)); \ 287 assemble_aligned_integer (2, GEN_INT (0x4e75)); \ 288 assemble_aligned_integer (4, const0_rtx); \ 289 assemble_aligned_integer (4, const0_rtx); \ 290 } 291 292 /* Redefine since we are using a different trampoline */ 293 #undef TRAMPOLINE_SIZE 294 #define TRAMPOLINE_SIZE 18 295 296 /* Emit RTL insns to initialize the variable parts of a trampoline. 297 FNADDR is an RTX for the address of the function's pure code. 298 CXT is an RTX for the static chain value for the function. */ 299 300 #undef INITIALIZE_TRAMPOLINE 301 #define INITIALIZE_TRAMPOLINE(TRAMP, FNADDR, CXT) \ 302 { \ 303 emit_move_insn (gen_rtx_MEM (SImode, plus_constant (TRAMP, 10)), CXT); \ 304 emit_move_insn (gen_rtx_MEM (SImode, plus_constant (TRAMP, 14)), FNADDR); \ 305 } 306