1 /* Target definitions for GNU compiler for mc680x0 running System V.4
2 Copyright (C) 1991, 1993, 1994 Free Software Foundation, Inc.
4 Written by Ron Guilmette (rfg@netcom.com) and Fred Fish (fnf@cygnus.com).
6 This file is part of GNU CC.
8 GNU CC is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2, or (at your option)
13 GNU CC is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with GNU CC; see the file COPYING. If not, write to
20 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
22 /* Use SGS_* macros to control compilation in m68k.md */
24 #define SGS_SWITCH_TABLES /* Different switch table handling */
26 #include "m68k/sgs.h" /* The m68k/SVR4 assembler is SGS based */
28 /* The SGS assembler requires a special definition of
29 ASM_IDENTIFY_GCC. We combine the m68k/sgs.h and the svr4.h
31 #undef ASM_IDENTIFY_GCC
33 #include "svr4.h" /* Pick up the generic SVR4 macros */
35 /* See m68k.h. 7 means 68020 with 68881. */
37 #ifndef TARGET_DEFAULT
38 #define TARGET_DEFAULT (5 /*68020*/ + 2 /*68881*/)
41 /* When using an SGS assembler, modify the name of the artificial label which
42 identifies this file as having been compiled with gcc, and the macro that
43 emits such a label in the assembly output, to use '%' rather than '.' */
45 #undef ASM_IDENTIFY_GCC
46 #define ASM_IDENTIFY_GCC(FILE) \
49 if (write_symbols != DBX_DEBUG) \
50 fputs ("gcc2_compiled%:\n", FILE); \
54 /* Override the definition of NO_DOLLAR_IN_LABEL in svr4.h, for special
55 g++ assembler names. When this is defined, g++ uses embedded '.'
56 characters and some m68k assemblers have problems with this. The
57 chances are much greater that any particular assembler will permit
58 embedded '$' characters. */
60 #undef NO_DOLLAR_IN_LABEL
62 /* Define PCC_STATIC_STRUCT_RETURN if the convention on the target machine
63 is to use the nonreentrant technique for returning structure and union
64 values, as commonly implemented by the AT&T Portable C Compiler (PCC).
65 When defined, the gcc option -fpcc-struct-return can be used to cause
66 this form to be generated. When undefined, the option does nothing.
67 For m68k SVR4, the convention is to use a reentrant technique compatible
68 with the gcc default, so override the definition of this macro in m68k.h */
70 #undef PCC_STATIC_STRUCT_RETURN
72 /* Provide a set of pre-definitions and pre-assertions appropriate for
73 the m68k running svr4. __svr4__ is our extension. */
75 #define CPP_PREDEFINES \
76 "-Dm68k -Dunix -D__svr4__ -D__motorola__ \
77 -Asystem(unix) -Asystem(svr4) -Acpu(m68k) -Amachine(m68k)"
79 /* Test to see if the target includes a 68881 by default, and use CPP_SPEC
80 to control whether or not __HAVE_68881__ is defined by default or not.
81 If a 68881 is the default, gcc will use inline 68881 instructions, by
82 predefining __HAVE_68881__, unless -msoft-float is specified.
83 If a 68881 is not the default, gcc will only define __HAVE_68881__ if
84 -m68881 is specified. */
86 #if TARGET_DEFAULT & 2
87 #define CPP_SPEC "%{!msoft-float:-D__HAVE_68881__}"
89 #define CPP_SPEC "%{m68881:-D__HAVE_68881__}"
92 /* Output assembler code to FILE to increment profiler label # LABELNO
93 for profiling a function entry. We override the definition in m68k.h
94 and match the way the native m68k/SVR4 compiler does profiling, with the
95 address of the profile counter in a1, not a0, and using bsr rather
98 #undef FUNCTION_PROFILER
99 #define FUNCTION_PROFILER(FILE, LABELNO) \
100 asm_fprintf ((FILE), "\tlea.l\t(%LLP%d,%Rpc),%Ra1\n\tbsr\t_mcount\n", \
103 /* Local common symbols are declared to the assembler with ".lcomm" rather
104 than ".bss", so override the definition in svr4.h */
107 #define BSS_ASM_OP ".lcomm"
109 /* Register in which address to store a structure value is passed to a
110 function. The default in m68k.h is a1. For m68k/SVR4 it is a0. */
112 #undef STRUCT_VALUE_REGNUM
113 #define STRUCT_VALUE_REGNUM 8
115 #define ASM_COMMENT_START "#"
117 #undef TYPE_OPERAND_FMT
118 #define TYPE_OPERAND_FMT "@%s"
120 /* Define how the m68k registers should be numbered for Dwarf output.
121 The numbering provided here should be compatible with the native
122 SVR4 SDB debugger in the m68k/SVR4 reference port, where d0-d7
123 are 0-7, a0-a8 are 8-15, and fp0-fp7 are 16-23. */
125 #define DBX_REGISTER_NUMBER(REGNO) (REGNO)
127 /* The ASM_OUTPUT_SKIP macro is first defined in m68k.h, using ".skip".
128 It is then overridden by m68k/sgs.h to use ".space", and again by svr4.h
129 to use ".zero". The m68k/SVR4 assembler uses ".space", so repeat the
130 definition from m68k/sgs.h here. Note that ASM_NO_SKIP_IN_TEXT is
131 defined in m68k/sgs.h, so we don't have to repeat it here. */
133 #undef ASM_OUTPUT_SKIP
134 #define ASM_OUTPUT_SKIP(FILE,SIZE) \
135 fprintf (FILE, "\t%s %u\n", SPACE_ASM_OP, (SIZE))
137 /* 1 if N is a possible register number for a function value.
138 For m68k/SVR4 allow d0, a0, or fp0 as return registers, for integral,
139 pointer, or floating types, respectively. Reject fp0 if not using a
140 68881 coprocessor. */
142 #undef FUNCTION_VALUE_REGNO_P
143 #define FUNCTION_VALUE_REGNO_P(N) \
144 ((N) == 0 || (N) == 8 || (TARGET_68881 && (N) == 16))
146 /* Define this to be true when FUNCTION_VALUE_REGNO_P is true for
147 more than one register. */
149 #undef NEEDS_UNTYPED_CALL
150 #define NEEDS_UNTYPED_CALL 1
152 /* Define how to generate (in the callee) the output value of a function
153 and how to find (in the caller) the value returned by a function. VALTYPE
154 is the data type of the value (as a tree). If the precise function being
155 called is known, FUNC is its FUNCTION_DECL; otherwise, FUNC is 0.
156 For m68k/SVR4 generate the result in d0, a0, or fp0 as appropriate. */
158 #undef FUNCTION_VALUE
159 #define FUNCTION_VALUE(VALTYPE, FUNC) \
160 (TREE_CODE (VALTYPE) == REAL_TYPE && TARGET_68881 \
161 ? gen_rtx (REG, TYPE_MODE (VALTYPE), 16) \
162 : (POINTER_TYPE_P (VALTYPE) \
163 ? gen_rtx (REG, TYPE_MODE (VALTYPE), 8) \
164 : gen_rtx (REG, TYPE_MODE (VALTYPE), 0)))
166 /* For compatibility with the large body of existing code which does not
167 always properly declare external functions returning pointer types, the
168 m68k/SVR4 convention is to copy the value returned for pointer functions
169 from a0 to d0 in the function epilogue, so that callers that have
170 neglected to properly declare the callee can still find the correct return
173 extern int current_function_returns_pointer;
174 #define FUNCTION_EXTRA_EPILOGUE(FILE, SIZE) \
176 if ((current_function_returns_pointer) && \
177 ! find_equiv_reg (0, get_last_insn (), 0, 0, 0, 8, Pmode)) \
178 asm_fprintf (FILE, "\tmov.l %Ra0,%Rd0\n"); \
181 /* Define how to find the value returned by a library function assuming the
183 For m68k/SVR4 look for integer values in d0, pointer values in d0
184 (returned in both d0 and a0), and floating values in fp0. */
187 #define LIBCALL_VALUE(MODE) \
188 (((MODE) == SFmode || (MODE) == DFmode) && TARGET_68881 \
189 ? gen_rtx (REG, (MODE), 16) \
190 : gen_rtx (REG, (MODE), 0))
192 /* Boundary (in *bits*) on which stack pointer should be aligned.
193 The m68k/SVR4 convention is to keep the stack pointer longword aligned. */
195 #undef STACK_BOUNDARY
196 #define STACK_BOUNDARY 32
198 /* Alignment of field after `int : 0' in a structure.
199 For m68k/SVR4, this is the next longword boundary. */
201 #undef EMPTY_FIELD_BOUNDARY
202 #define EMPTY_FIELD_BOUNDARY 32
204 /* No data type wants to be aligned rounder than this.
205 For m68k/SVR4, some types (doubles for example) are aligned on 8 byte
208 #undef BIGGEST_ALIGNMENT
209 #define BIGGEST_ALIGNMENT 64
211 /* SVR4 m68k assembler is bitching on the `comm i,1,1' which askes for
212 1 byte alignment. Don't generate alignment for COMMON seems to be
213 safer until we the assembler is fixed. */
214 #undef ASM_OUTPUT_ALIGNED_COMMON
215 /* Same problem with this one. */
216 #undef ASM_OUTPUT_ALIGNED_LOCAL
218 /* The `string' directive on m68k svr4 does not handle string with
219 escape char (ie., `\') right. Use normal way to output ASCII bytes
220 seems to be safer. */
221 #undef ASM_OUTPUT_ASCII
222 #define ASM_OUTPUT_ASCII(FILE,PTR,LEN) \
224 register int sp = 0, lp = 0, ch; \
225 fprintf ((FILE), "\t%s ", BYTE_ASM_OP); \
228 if (ch > ' ' && ! (ch & 0x80) && ch != '\\') \
230 fprintf ((FILE), "'%c", ch); \
234 fprintf ((FILE), "0x%x", ch); \
238 if ((sp % 10) == 0) \
240 fprintf ((FILE), "\n\t%s ", BYTE_ASM_OP); \
244 putc (',', (FILE)); \
247 } while (sp < (LEN)); \
248 putc ('\n', (FILE)); \
251 /* SVR4 m68k assembler is bitching on the syntax `2.b'.
252 So use the "LLDnnn-LLnnn" format. Define LLDnnn after the table. */
254 #undef ASM_OUTPUT_CASE_END
255 #define ASM_OUTPUT_CASE_END(FILE,NUM,TABLE) \
257 if (switch_table_difference_label_flag) \
258 asm_fprintf ((FILE), "\t%s %LLD%d,%LL%d\n", SET_ASM_OP, (NUM), (NUM));\
259 switch_table_difference_label_flag = 0; \
262 int switch_table_difference_label_flag;
264 #undef ASM_OUTPUT_COMMON
265 #undef ASM_OUTPUT_LOCAL
266 #define ASM_OUTPUT_COMMON(FILE, NAME, SIZE, ROUNDED) \
267 ( fputs (".comm ", (FILE)), \
268 assemble_name ((FILE), (NAME)), \
269 fprintf ((FILE), ",%u\n", (SIZE)))
271 #define ASM_OUTPUT_LOCAL(FILE, NAME, SIZE, ROUNDED) \
272 ( fputs (".lcomm ", (FILE)), \
273 assemble_name ((FILE), (NAME)), \
274 fprintf ((FILE), ",%u\n", (SIZE)))
276 /* Override the definition in svr4.h. In m68k svr4, using swbeg is the
277 standard way to do switch table. */
278 #undef ASM_OUTPUT_BEFORE_CASE_LABEL
279 #define ASM_OUTPUT_BEFORE_CASE_LABEL(FILE,PREFIX,NUM,TABLE) \
280 fprintf ((FILE), "\t%s &%d\n", SWBEG_ASM_OP, XVECLEN (PATTERN (TABLE), 1));
282 /* In m68k svr4, a symbol_ref rtx can be a valid PIC operand if it is an
283 operand of a function call. */
284 #undef LEGITIMATE_PIC_OPERAND_P
285 #define LEGITIMATE_PIC_OPERAND_P(X) \
286 (! symbolic_operand (X, VOIDmode) \
287 || ((GET_CODE(X) == SYMBOL_REF) && SYMBOL_REF_FLAG(X)))
289 /* Turn off function cse if we are doing PIC. We always want function call
290 to be done as `bsr foo@PLTPC', so it will force the assembler to create
291 the PLT entry for `foo'. Doing function cse will cause the address of `foo'
292 to be loaded into a register, which is exactly what we want to avoid when
293 we are doing PIC on svr4 m68k. */
294 #undef OVERRIDE_OPTIONS
295 #define OVERRIDE_OPTIONS \
297 if (flag_pic) flag_no_function_cse = 1; \
298 if (! TARGET_68020 && flag_pic == 2) \
299 error("-fPIC is not currently supported on the 68000 or 68010\n"); \